Zero-field splitting in the isoelectronic aqueous Gd(III) and Eu(II) complexes from a first principles analysis

NASA Astrophysics Data System (ADS)

Khan, S.; Peters, V.; Kowalewski, J.; Odelius, M.

2018-03-01

The zero-field splitting (ZFS) of the ground state octet in aqueous Eu(II) and Gd(III) solutions was investigated through multi- configurational quantum chemical calculations and ab initio molecular dynamics (AIMD) simulations. Investigation of the ZFS of the lanthanide ions is essential to understand the electron spin dynamics and nuclear spin relaxation around paramagnetic ions and consequently the mechanisms underlying applications like magnetic resonance imaging. We found by comparing clusters at identical geometries but different metallic centres that there is not a simple relationship for their ZFS, in spite of the complexes being isoelectronic - each containing 7 unpaired f electrons. Through sampling it was established that inclusion of the first hydration shell has a dominant (over 90 %) influence on the ZFS. Extended sampling of aqueous Gd(III) showed that the 2 nd order spin Hamiltonian formalism is valid and that the rhombic ZFS component is decisive.

The structure of post-traumatic stress symptoms in survivors of war: confirmatory factor analyses of the Impact of Event Scale--revised.

PubMed

Morina, Nexhmedin; Böhme, Hendryk F; Ajdukovic, Dean; Bogic, Marija; Franciskovic, Tanja; Galeazzi, Gian M; Kucukalic, Abdulah; Lecic-Tosevski, Dusica; Popovski, Mihajlo; Schützwohl, Matthias; Stangier, Ulrich; Priebe, Stefan

2010-08-01

The study aimed at establishing the factor structure of the Impact of Event Scale-Revised (IES-R) in survivors of war. A total sample of 4167 participants with potentially traumatic experiences during the war in Ex-Yugoslavia was split into three samples: two independent samples of people who stayed in the area of conflict and one sample of refugees to Western European countries. Alternative models with three, four, and five factors of post-traumatic symptoms were tested in one sample. The other samples were used for cross-validation. Results indicated that the model of best fit had five factors, i.e., intrusion, avoidance, hyperarousal, numbing, and sleep disturbance. Model superiority was cross-validated in the two other samples. These findings suggest a five-factor model of post-traumatic stress symptoms in war survivors with numbing and sleep disturbance as separate factors in addition to intrusion, avoidance and hyperarousal. (c) 2010 Elsevier Ltd. All rights reserved.

Hyaline cartilage surface study with an environmental scanning electron microscope. An experimental study.

PubMed

Sastre, S; Suso, S; Segur, J M; Bori, G; Carbonell, J A; Agustí, E; Nuñez, M

2009-11-01

To obtain images of the articular surface of fresh osteochondral grafts using an environmental scanning electron microscope (ESEM). To evaluate and compare the main morphological aspects of the chondral surface of the fresh grafts. To develop a validated classification system on the basis of the images obtained via the ESEM. The study was based on osteochondral fragments from the internal condyle of the knee joint of New Zealand rabbits, corresponding to fresh chondral surface. One hundred images were obtained via the ESEM and these were classified by two observers according to a category system. The Kappa index and the corresponding confidence interval (CI) were calculated. Of the samples analysed, 62-72% had an even surface. Among the samples with an uneven surface 17-22% had a hillocky appearance and 12-16% a knobbly appearance. As regards splits, these were not observed in 92-95% of the surfaces; 4-7% showed superficial splits and only 1% deep splits. In 78-82% of cases no lacunae in the surface were observed, while 17-20% showed filled lacunae and only 1-2% presented empty lacunae. The study demonstrates that the ESEM is useful for obtaining and classifying images of osteochondral grafts.

Rural Parents’ Perceived Stigma of Seeking Mental Health Services for their Children: Development and Evaluation of a New Instrument

PubMed Central

Williams, Stacey L.; Polaha, Jodi

2014-01-01

The purpose of this paper was to examine the validity of score interpretations of an instrument developed to measure parents’ perceptions of stigma about seeking mental health services for their children. The validity of the score interpretations of the instrument was tested in two studies. Study 1 examined confirmatory factor analysis (CFA) employing a split half approach, and construct and criterion validity using the entire sample of parents in rural Appalachia whose children were experiencing psychosocial concerns (N=347), while Study 2 further examined CFA, construct and criterion validity, as well as predictive validity of the scores on the new scale using a general sample of parents in rural Appalachia (N=184). Results of exploratory and confirmatory factor analyses revealed support for a two factor model of parents’ perceived stigma, which represented both self and public forms of stigma associated with seeking mental health services for their children, and correlated with existing measures of stigma and other psychosocial variables. Further, the new self and public stigma scale significantly predicted parents’ willingness to seek services for children. PMID:24749752

Psychometric testing on the NLN Student Satisfaction and Self-Confidence in Learning, Simulation Design Scale, and Educational Practices Questionnaire using a sample of pre-licensure novice nurses.

PubMed

Franklin, Ashley E; Burns, Paulette; Lee, Christopher S

2014-10-01

In 2006, the National League for Nursing published three measures related to novice nurses' beliefs about self-confidence, scenario design, and educational practices associated with simulation. Despite the extensive use of these measures, little is known about their reliability and validity. The psychometric properties of the Student Satisfaction and Self-Confidence in Learning Scale, Simulation Design Scale, and Educational Practices Questionnaire were studied among a sample of 2200 surveys completed by novice nurses from a liberal arts university in the southern United States. Psychometric tests included item analysis, confirmatory and exploratory factor analyses in randomly-split subsamples, concordant and discordant validity, and internal consistency. All three measures have sufficient reliability and validity to be used in education research. There is room for improvement in content validity with the Student Satisfaction and Self-Confidence in Learning and Simulation Design Scale. This work provides robust evidence to ensure that judgments made about self-confidence after simulation, simulation design and educational practices are valid and reliable. Copyright © 2014 Elsevier Ltd. All rights reserved.

Multiplex detection of protein-protein interactions using a next generation luciferase reporter.

PubMed

Verhoef, Lisette G G C; Mattioli, Michela; Ricci, Fernanda; Li, Yao-Cheng; Wade, Mark

2016-02-01

Cell-based assays of protein-protein interactions (PPIs) using split reporter proteins can be used to identify PPI agonists and antagonists. Generally, such assays measure one PPI at a time, and thus counterscreens for on-target activity must be run in parallel or at a subsequent stage; this increases both the cost and time during screening. Split luciferase systems offer advantages over those that use split fluorescent proteins (FPs). This is since split luciferase offers a greater signal:noise ratio and, unlike split FPs, the PPI can be reversed upon small molecule treatment. While multiplexed PPI assays using luciferase have been reported, they suffer from low signal:noise and require fairly complex spectral deconvolution during analysis. Furthermore, the luciferase enzymes used are large, which limits the range of PPIs that can be interrogated due to steric hindrance from the split luciferase fragments. Here, we report a multiplexed PPI assay based on split luciferases from Photinus pyralis (firefly luciferase, FLUC) and the deep-sea shrimp, Oplophorus gracilirostris (NanoLuc, NLUC). Specifically, we show that the binding of the p53 tumor suppressor to its two major negative regulators, MDM2 and MDM4, can be simultaneously measured within the same sample, without the requirement for complex filters or deconvolution. We provide chemical and genetic validation of this system using MDM2-targeted small molecules and mutagenesis, respectively. Combined with the superior signal:noise and smaller size of split NanoLuc, this multiplexed PPI assay format can be exploited to study the induction or disruption of pairwise interactions that are prominent in many cell signaling pathways. Copyright © 2015 Elsevier B.V. All rights reserved.

[The Scope, Quality and Safety Requirements of Drug Abuse Testing].

PubMed

Küme, Tuncay; Karakükcü, Çiğdem; Pınar, Aslı; Coşkunol, Hakan

2017-01-01

The aim of this review is to inform about the scopes and requirements of drug abuse testing. Drug abuse testing is one of the tools for determination of drug use. It must fulfill the quality and safety requirements in judgmental legal and administrative decisions. Drug abuse testing must fulfill some requirements like selection of the appropriate test matrix, appropriate screening test panel, sampling in detection window, patient consent, identification of the donor, appropriate collection site, sample collection with observation, identification and control of the sample, specimen custody chain in preanalytical phase; analysis in authorized laboratories, specimen validity tests, reliable testing METHODS, strict quality control, two-step analysis in analytical phase; storage of the split specimen, confirmation of the split specimen in the objection, result custody chain, appropriate cut-off concentration, the appropriate interpretation of the result in postanalytical phase. The workflow and analytical processes of drug abuse testing are explained in last regulation of the Department of Medical Laboratory Services, Ministry of Health in Turkey. The clinical physicians have to know and apply the quality and safety requirements in drug abuse testing according to last regulations in Turkey.

Construct measurement quality improves predictive accuracy in violence risk assessment: an illustration using the personality assessment inventory.

PubMed

Hendry, Melissa C; Douglas, Kevin S; Winter, Elizabeth A; Edens, John F

2013-01-01

Much of the risk assessment literature has focused on the predictive validity of risk assessment tools. However, these tools often comprise a list of risk factors that are themselves complex constructs, and focusing on the quality of measurement of individual risk factors may improve the predictive validity of the tools. The present study illustrates this concern using the Antisocial Features and Aggression scales of the Personality Assessment Inventory (Morey, 1991). In a sample of 1,545 prison inmates and offenders undergoing treatment for substance abuse (85% male), we evaluated (a) the factorial validity of the ANT and AGG scales, (b) the utility of original ANT and AGG scales and newly derived ANT and AGG scales for predicting antisocial outcomes (recidivism and institutional infractions), and (c) whether items with a stronger relationship to the underlying constructs (higher factor loadings) were in turn more strongly related to antisocial outcomes. Confirmatory factor analyses (CFAs) indicated that ANT and AGG items were not structured optimally in these data in terms of correspondence to the subscale structure identified in the PAI manual. Exploratory factor analyses were conducted on a random split-half of the sample to derive optimized alternative factor structures, and cross-validated in the second split-half using CFA. Four-factor models emerged for both the ANT and AGG scales, and, as predicted, the size of item factor loadings was associated with the strength with which items were associated with institutional infractions and community recidivism. This suggests that the quality by which a construct is measured is associated with its predictive strength. Implications for risk assessment are discussed. Copyright © 2013 John Wiley & Sons, Ltd.

A tool for developing an automatic insect identification system based on wing outlines

PubMed Central

Yang, He-Ping; Ma, Chun-Sen; Wen, Hui; Zhan, Qing-Bin; Wang, Xin-Li

2015-01-01

For some insect groups, wing outline is an important character for species identification. We have constructed a program as the integral part of an automated system to identify insects based on wing outlines (DAIIS). This program includes two main functions: (1) outline digitization and Elliptic Fourier transformation and (2) classifier model training by pattern recognition of support vector machines and model validation. To demonstrate the utility of this program, a sample of 120 owlflies (Neuroptera: Ascalaphidae) was split into training and validation sets. After training, the sample was sorted into seven species using this tool. In five repeated experiments, the mean accuracy for identification of each species ranged from 90% to 98%. The accuracy increased to 99% when the samples were first divided into two groups based on features of their compound eyes. DAIIS can therefore be a useful tool for developing a system of automated insect identification. PMID:26251292

Transferring Goods or Splitting a Resource Pool

ERIC Educational Resources Information Center

Dijkstra, Jacob; Van Assen, Marcel A. L. M.

2008-01-01

We investigated the consequences for exchange outcomes of the violation of an assumption underlying most social psychological research on exchange. This assumption is that the negotiated direct exchange of commodities between two actors (pure exchange) can be validly represented as two actors splitting a fixed pool of resources (split pool…

Young investigator challenge: Validation and optimization of immunohistochemistry protocols for use on cellient cell block specimens.

PubMed

Sauter, Jennifer L; Grogg, Karen L; Vrana, Julie A; Law, Mark E; Halvorson, Jennifer L; Henry, Michael R

2016-02-01

The objective of the current study was to establish a process for validating immunohistochemistry (IHC) protocols for use on the Cellient cell block (CCB) system. Thirty antibodies were initially tested on CCBs using IHC protocols previously validated on formalin-fixed, paraffin-embedded tissue (FFPE). Cytology samples were split to generate thrombin cell blocks (TCB) and CCBs. IHC was performed in parallel. Antibody immunoreactivity was scored, and concordance or discordance in immunoreactivity between the TCBs and CCBs for each sample was determined. Criteria for validation of an antibody were defined as concordant staining in expected positive and negative cells, in at least 5 samples each, and concordance in at least 90% of the samples total. Antibodies that failed initial validation were retested after alterations in IHC conditions. Thirteen of the 30 antibodies (43%) did not meet initial validation criteria. Of those, 8 antibodies (calretinin, clusters of differentiation [CD] 3, CD20, CDX2, cytokeratin 20, estrogen receptor, MOC-31, and p16) were optimized for CCBs and subsequently validated. Despite several alterations in conditions, 3 antibodies (Ber-EP4, D2-40, and paired box gene 8 [PAX8]) were not successfully validated. Nearly one-half of the antibodies tested in the current study failed initial validation using IHC conditions that were established in the study laboratory for FFPE material. Although some antibodies subsequently met validation criteria after optimization of conditions, a few continued to demonstrate inadequate immunoreactivity. These findings emphasize the importance of validating IHC protocols for methanol-fixed tissue before clinical use and suggest that optimization for alcohol fixation may be needed to obtain adequate immunoreactivity on CCBs. © 2016 American Cancer Society.

Construct validity test of evaluation tool for professional behaviors of entry-level occupational therapy students in the United States.

PubMed

Yuen, Hon K; Azuero, Andres; Lackey, Kaitlin W; Brown, Nicole S; Shrestha, Sangita

2016-01-01

This study aimed to test the construct validity of an instrument to measure student professional behaviors in entry-level occupational therapy (OT) students in the academic setting. A total of 718 students from 37 OT programs across the United States answered a self-assessment survey of professional behavior that we developed. The survey consisted of ranking 28 attributes, each on a 5-point Likert scale. A split-sample approach was used for exploratory and then confirmatory factor analysis. A three-factor solution with nine items was extracted using exploratory factor analysis [EFA] (n=430, 60%). The factors were 'Commitment to Learning' (2 items), 'Skills for Learning' (4 items), and 'Cultural Competence' (3 items). Confirmatory factor analysis (CFA) on the validation split (n=288, 40%) indicated fair fit for this three-factor model (fit indices: CFI=0.96, RMSEA=0.06, and SRMR=0.05). Internal consistency reliability estimates of each factor and the instrument ranged from 0.63 to 0.79. Results of the CFA in a separate validation dataset provided robust measures of goodness-of-fit for the three-factor solution developed in the EFA, and indicated that the three-factor model fitted the data well enough. Therefore, we can conclude that this student professional behavior evaluation instrument is a structurally validated tool to measure professional behaviors reported by entry-level OT students. The internal consistency reliability of each individual factor and the whole instrument was considered to be adequate to good.

New Insight into the Angle Insensitivity of Ultrathin Planar Optical Absorbers for Broadband Solar Energy Harvesting.

PubMed

Liu, Dong; Yu, Haitong; Duan, Yuanyuan; Li, Qiang; Xuan, Yimin

2016-09-01

Two challenging problems still remain for optical absorbers consisting of an ultrathin planar semiconductor film on top of an opaque metallic substrate. One is the angle-insensitive mechanism and the other is the system design needed for broadband solar energy harvesting. Here, first we theoretically demonstrates that the high refractive index, instead of the ultrathin feature as reported in previous studies, is the physical origin of the angle insensitivity for ultrathin planar optical absorbers. They exhibit omnidirectional resonance for TE polarization due to the high complex refractive index difference between the semiconductor and the air, while for TM polarization the angle insensitivity persists up to an incident angle related to the semiconductor refractive index. These findings were validated by fabricating and characterizing an 18 nm Ge/Ag absorber sample (representative of small band gap semiconductors for photovoltaic applications) and a 22 nm hematite/Ag sample (representative of large band gap semiconductors for photoelectrochemical applications). Then, we took advantage of angle insensitivity and designed a spectrum splitting configuration for broadband solar energy harvesting. The cascaded solar cell and unassisted solar water splitting systems have photovoltaic and photoelectrochemical cells that are also spectrum splitters, so an external spectrum splitting element is not needed.

Willingness-to-pay function for two fuel treatments to reduce wildfire acreage burned: A scope test and comparison of white and hispanic households

Treesearch

John B. Loomis; Hung Le Trong; Armando González-Cabán

2009-01-01

We estimate a marginal benefit function for using prescribed burning and mechanical fuel reduction programs to reduce acres burned by wildfire in three states. Since each state had different acre reductions, a statistically significant coefficient on the reduction in acres burned is also a split sample scope test frequently used as an indicator of the internal validity...

Split-mouth design in Paediatric Dentistry clinical trials.

PubMed

Pozos-Guillén, A; Chavarría-Bolaños, D; Garrocho-Rangel, A

2017-03-01

The aim of this article was to describe the essential concepts of the split-mouth design, its underlying assumptions, advantages, limitations, statistical considerations, and possible applications in Paediatric Dentistry clinical investigation. In Paediatric Dentistry clinical investigation, and as part of randomised controlled trials, the split-mouth design is commonly used. The design is characterised by subdividing the child's dentition into halves (right and left), where two different treatment modalities are assigned to one side randomly, in order to allow further outcome evaluation. Each participant acts as their own control by making within- patient rather than between-patient comparisons, thus diminishing inter-subject variability and increasing study accuracy and power. However, the main problem with this design comprises the potential contamination of the treatment effect from one side to the other, or the "carry-across effect"; likewise, this design is not indicated when the oral disease to be treated is not symmetrically distributed (e.g. severity) in the mouth of children. Thus, in spite of its advantages, the split-mouth design can only be applied in a limited number of strictly selected cases. In order to obtain valid and reliable data from split mouth design studies, it is necessary to evaluate the risk of carry-across effect as well as to carefully analise and select adequate inclusion criteria, sample-size calculation and method of statistical analysis.

Psychometric Properties of the Chinese Version of the Brief Borderline Symptom List in Undergraduate Students and Clinical Patients.

PubMed

Yang, Huihui; Lei, Xiaoxia; Zhong, Mingtian; Zhou, Qi; Ling, Yu; Jungkunz, Martin; Yi, Jinyao

2018-01-01

The brief version of the Borderline Symptom List (BSL-23) is a self-rated scale developed from the initial 95-item version of Borderline Symptom List (BSL-95). The current study aimed to evaluate the psychometric properties of the Chinese version of the BSL-23. A total of 570 undergraduate students and 323 clinical patients completed the BSL-23, the borderline subscale of the Personality Diagnostic Questionnaire (PDQ-4+), the Center for Epidemiologic Studies Depression Scale (CES-D), the Barratt Impulsiveness Scale, 11th version (BIS-11), the Childhood Trauma Questionnaire (CTQ) and the Attachment Style Questionnaire (ASQ). A Confirmatory Factor Analysis (CFA) was conducted to test the one-factor structure of the BSL-23. Cronbach's alpha, Omega coefficient, Split-Half coefficient, Mean Inter-Item Correlation (M IC ) and test-retest reliability were also measured. The correlations between the BSL-23 and other psychological variables were used to assess criterion-related validity and convergent validity. Participants who scored ≥ 5 on the borderline subscale of the PDQ-4+ were placed into the borderline personality disorder (BPD) screening-positive group, while the others were placed into the screening-negative group. Independent sample t -tests were performed to examine the differences in BSL-23 scores between the BPD screening-positive group and the BPD screening-negative group. The CFA results supported the one-factor structure of the BSL-23 in both samples. The internal consistency was high both in the undergraduate sample (Cronbach's α = 0.93, Omega = 0.95, Split-Half coefficient = 0.89, M IC = 0.38) and the clinical sample (Cronbach's α = 0.97, Omega = 0.97, Split-Half coefficient = 0.96, M IC = 0.56). The test-retest reliability within 2 weeks was 0.62. The BSL-23 displayed moderate to high correlations with the PDQ-4+-Borderline subscale, the CES-D, the BIS-11, the CTQ and the ASQ ( r = 0.35 - 0.70). In addition, the BSL-23 discriminated between the BPD screening-positive and the BPD screening-negative participants, and also between the patient sample and undergraduate sample. In conclusion, the Chinese version of the BSL-23 has satisfactory psychometric properties to assess BPD symptoms.

Development and Validation of Videogame Addiction Scale for Children (VASC).

PubMed

Yılmaz, Eyüp; Griffiths, Mark D; Kan, Adnan

2017-01-01

The aim of the present study was to develop a valid and reliable Videogame Addiction Scale for Children (VASC). The data were derived from 780 children who completed the Videogame Addiction Scale (405 girls and 375 boys; 48.1% ranging in age from 9 to 12 years). The sample was randomly split into two different sub-samples (sample 1, n  = 400; sample 2, n  = 380). Sample 1 was used to perform exploratory factor analysis (EFA) to define the factorial structure of VASC. As a result of EFA, a four-factor structure comprising 21 items was obtained and explained 55% of the total variance (the four factors being "self-control," "reward/reinforcement," "problems," and "involvement"). The internal consistency reliability of VASC has found 0.89. Confirmatory factor analysis (CFA) was performed to confirm the factorial structure obtained by EFA in the remaining half of sample ( n  = 390). The obtained fit indices from the CFA confirmed the structure of the EFA. The 21-item VASC has good psychometric properties that can be used among Turkish schoolchildren populations.

Comparison of consumer perception and acceptability for steaks cooked to different endpoints: validation of photographic approach.

PubMed

Chan, Sheung-Hang; Moss, Bruce W; Farmer, Linda J; Gordon, Alan; Cuskelly, Geraldine J

2013-02-15

Photographs have been used to enhance consumer reporting of preference of meat doneness, however, the use of photographs has not been validated for this purpose. This study used standard cooking methods to produce steaks of five different degrees of doneness (rare medium, medium well, well done and very well done) to study the consumer's perception of doneness, from both the external and internal surface of the cooked steak and also from corresponding photographs of each sample. Consumers evaluated each surface of the cooked steaks in relation to doneness for acceptability, 'just about right' and perception of doneness. Data were analysed using a split plot ANOVA and least significant test. Perception scores (for both external and internal surfaces) between different presentation methods (steak samples and corresponding photos), were not significantly different (p>0.05). The result indicates that photographs can be used as a valid approach for assessing preference for meat doneness. Copyright © 2012 Elsevier Ltd. All rights reserved.

Rural parents' perceived stigma of seeking mental health services for their children: development and evaluation of a new instrument.

PubMed

Williams, Stacey L; Polaha, Jodi

2014-09-01

The purpose of our research was to examine the validity of score interpretations of an instrument developed to measure parents' perceptions of stigma about seeking mental health services for their children. The validity of the score interpretations of the instrument was tested in 2 studies. Study 1 employed confirmatory factor analysis (CFA), using a split half approach, and construct and criterion validity on data from the entire sample of parents in rural Appalachia whose children were experiencing psychosocial concerns (N = 347), while Study 2 employed CFA, construct and criterion validity, and predictive validity of the scores on data from a general sample of parents in rural Appalachia (N = 184). Results of exploratory and confirmatory factor analyses revealed support for a 2-factor model of parents' perceived stigma, which represented both self and public forms of stigma associated with seeking mental health services for their children, and correlated with existing measures of stigma and other psychosocial variables. Further, the new self and public stigma scale significantly predicted parents' willingness to seek services for children. PsycINFO Database Record (c) 2014 APA, all rights reserved.

Creation and validation of the self-efficacy instrument for physical education teacher education majors toward inclusion.

PubMed

Block, Martin E; Hutzler, Yeshayahu; Barak, Sharon; Klavina, Aija

2013-04-01

The purpose was to validate a self-efficacy (SE) instrument toward including students with disability in physical education (PE). Three scales referring to intellectual disabilities (ID), physical disabilities (PD), or visual impairments (VI) were administered to 486 physical education teacher education (PETE) majors. The sample was randomly split, and exploratory and confirmatory factor analyses (EFA and CFA, respectively) were conducted. After deleting items that did not meet inclusion criteria, EFA item loadings ranged from 0.53 to 0.91, and Cronbach's alpha reliability was high (for ID = .86, PD = .90, and VI = .92). CFA showed that the ID scale demonstrated good goodness-of-fit, whereas in the PD and in the VI scales demonstrated moderate fit. Thus, the content and construct validity of the instrument was supported.

Observations from a 4-year contamination study of a sample depth profile through Martian meteorite Nakhla.

PubMed

Toporski, Jan; Steele, Andrew

2007-04-01

Morphological, compositional, and biological evidence indicates the presence of numerous well-developed microbial hyphae structures distributed within four different sample splits of the Nakhla meteorite obtained from the British Museum (allocation BM1913,25). By examining depth profiles of the sample splits over time, morphological changes displayed by the structures were documented, as well as changes in their distribution on the samples, observations that indicate growth, decay, and reproduction of individual microorganisms. Biological staining with DNA-specific molecular dyes followed by epifluorescence microscopy showed that the hyphae structures contain DNA. Our observations demonstrate the potential of microbial interaction with extraterrestrial materials, emphasize the need for rapid investigation of Mars return samples as well as any other returned or impactor-delivered extraterrestrial materials, and suggest the identification of appropriate storage conditions that should be followed immediately after samples retrieved from the field are received by a handling/curation facility. The observations are further relevant in planetary protection considerations as they demonstrate that microorganisms may endure and reproduce in extraterrestrial materials over long (at least 4 years) time spans. The combination of microscopy images coupled with compositional and molecular staining techniques is proposed as a valid method for detection of life forms in martian materials as a first-order assessment. Time-resolved in situ observations further allow observation of possible (bio)dynamics within the system.

Creating ensembles of decision trees through sampling

DOEpatents

Kamath, Chandrika; Cantu-Paz, Erick

2005-08-30

A system for decision tree ensembles that includes a module to read the data, a module to sort the data, a module to evaluate a potential split of the data according to some criterion using a random sample of the data, a module to split the data, and a module to combine multiple decision trees in ensembles. The decision tree method is based on statistical sampling techniques and includes the steps of reading the data; sorting the data; evaluating a potential split according to some criterion using a random sample of the data, splitting the data, and combining multiple decision trees in ensembles.

Psychometric evaluation of the Chinese version of the fear of intimacy with helping professionals scale

PubMed Central

Chan, Kin Sun

2018-01-01

Objectives This study aimed to evaluate the internal consistency, reliability, convergent validity, known-group comparisons, and structural validity of the Chinese version of Fear of Intimacy with Helping Professionals (C–FIS–HP) scale in Macau. Methods A cross-sectional design was used on a sample of 593 older people in 6 health centers. We used Chinese version of Exercise of Self-Care Agency Scale (C-ESCAS) and Morisky 4-item medication adherence scale to evaluate self-care actions and medication adherence. The internal consistency and reliability of C–FIS–HP were analyzed using the Spearman-Brown split-half reliability, Cronbach’s alpha, and test–retest reliability. Convergent validity was tested the construct of C–FIS–HP and self-care actions. Known-group comparisons differentiated predefined groups in an expected direction. Two separated samples were used to test the structural validity. An exploratory factor analysis (EFA) tested the factor structure of C–FISHP using the principal axis factoring. A confirmatory factor analysis (CFA) was further conducted to confirm the factor structure constructed in the prior EFA. Results The C–FIS–HP had a Spearman-Brown split-half coefficient, Cronbach’s alpha, and intraclass correlation coefficient of 0.96, 0.93, and 0.96, respectively. Convergent validity was satisfactory with significantly correlations between the C-FIS-HP and C-ESCAS. C–FIS–HP to differentiate the differences between high-, moderate-, and low- medication adherence groups. EFA demonstrated a two-factor structure among 297 older people. A first-order CFA was performed to confirm the construct dimensionality of C–FIS–HP with satisfactory fit indices (NFI = 0.92; IFI = 0.95; TLI = 0.94; CFI = 0.95 and RMSEA = 0.07) among 296 older people. Conclusions C–FIS–HP is a reliable and valid test for assessing helping relationships in older Chinese people. Health professionals can use C–FIS–HP as a clinical tool to assess the comfort level of patients in a helping relationship, and use this information to develop culturally sensitive therapeutic interventions and treatment plans. Further studies need to be conducted concerning the different psychometric properties, as well as the application of C–FIS–HP in various regions. PMID:29795563

Spanish adaptation of social withdrawal motivation and frequency scales.

PubMed

Indias García, Sílvia; De Paúl Ochotorena, Joaquín

2016-11-01

To adapt into Spanish three scales measuring frequency (SWFS) and motivation for social withdrawal (CSPS and SWMS) and to develop a scale capable of assessing the five motivations for social withdrawal. Participants were 1,112 Spanish adolescents, aged 12-17 years. The sample was randomly split into two groups in which exploratory and confirmatory (CFA) factor analyses were performed separately. A sample of adolescents in residential care (n = 128) was also used to perform discriminant validity analyses. SWFS was reduced to eight items that account for 40% of explained variance (PVE), and its reliability is high. SWMS worked adequately in the original version, according to CFA. Some items from the CSPS were removed from the final Spanish version. The newly developed scale (SWMS-5D) is composed of 20 items including five subscales: Peer Isolation, Unsociability, Shyness, Low Mood and Avoidance. Analyses reveal adequate convergent and discriminant validities. The resulting SWFS-8 and SWMS-5D could be considered useful instruments to assess frequency and motivation for social withdrawal in Spanish samples.

Automatic detection of cone photoreceptors in split detector adaptive optics scanning light ophthalmoscope images.

PubMed

Cunefare, David; Cooper, Robert F; Higgins, Brian; Katz, David F; Dubra, Alfredo; Carroll, Joseph; Farsiu, Sina

2016-05-01

Quantitative analysis of the cone photoreceptor mosaic in the living retina is potentially useful for early diagnosis and prognosis of many ocular diseases. Non-confocal split detector based adaptive optics scanning light ophthalmoscope (AOSLO) imaging reveals the cone photoreceptor inner segment mosaics often not visualized on confocal AOSLO imaging. Despite recent advances in automated cone segmentation algorithms for confocal AOSLO imagery, quantitative analysis of split detector AOSLO images is currently a time-consuming manual process. In this paper, we present the fully automatic adaptive filtering and local detection (AFLD) method for detecting cones in split detector AOSLO images. We validated our algorithm on 80 images from 10 subjects, showing an overall mean Dice's coefficient of 0.95 (standard deviation 0.03), when comparing our AFLD algorithm to an expert grader. This is comparable to the inter-observer Dice's coefficient of 0.94 (standard deviation 0.04). To the best of our knowledge, this is the first validated, fully-automated segmentation method which has been applied to split detector AOSLO images.

INNOVATIVE TECHNOLOGY EVALUATION REPORT ...

EPA Pesticide Factsheets

The Split Core Sampler for Submerged Sediments (Split Core Sampler) designed and fabricated by Arts Manufacturing & Supply, Inc., was demonstrated under the U.S. Environmental Protection Agency (EPA) Superfund Innovative Technology Evaluation Program in April and May 1999 at sites in EPA Regions 1 and 5, respectively. In addition to assessing ease of sampler operation, key objectives of the demonstration included evaluating the samplers ability to (1) consistently collect a given volume of sediment, (2) consistently collect sediment in a given depth interval, (3) collect samples with consistent characteristics from a homogenous layer of sediment, and (4) collect samples under a variety of site conditions. This report describes the demonstration results for the Split Core Sampler and two conventional samplers (the Hand Corer and Vibrocorer) used as reference samplers. During the demonstration, the Split Core Sampler performed as well as or better than the reference samplers. Based on visual observations, both the Split Core Sampler and reference samplers collected partially compressed samples of consolidated and unconsolidated sediments from the sediment surface downward; sample representativeness may be questionable because of core shortening and core compression. Sediment stratification was preserved for both consolidated and unconsolidated sediment samples collected by the Split Core Sampler and reference samplers. No sampler was able to collect samples

Development and validation of green eating behaviors, stage of change, decisional balance, and self-efficacy scales in college students.

PubMed

Weller, Kathryn E; Greene, Geoffrey W; Redding, Colleen A; Paiva, Andrea L; Lofgren, Ingrid; Nash, Jessica T; Kobayashi, Hisanori

2014-01-01

To develop and validate an instrument to assess environmentally conscious eating (Green Eating [GE]) behavior (BEH) and GE Transtheoretical Model constructs including Stage of Change (SOC), Decisional Balance (DB), and Self-efficacy (SE). Cross-sectional instrument development survey. Convenience sample (n = 954) of 18- to 24-year-old college students from a northeastern university. The sample was randomly split: (N1) and (N2). N1 was used for exploratory factor analyses using principal components analyses; N2 was used for confirmatory analyses (structural modeling) and reliability analyses (coefficient α). The full sample was used for measurement invariance (multi-group confirmatory analyses) and convergent validity (BEH) and known group validation (DB and SE) by SOC using analysis of variance. Reliable (α > .7), psychometrically sound, and stable measures included 2 correlated 5-item DB subscales (Pros and Cons), 2 correlated SE subscales (school [5 items] and home [3 items]), and a single 6-item BEH scale. Most students (66%) were in Precontemplation and Contemplation SOC. Behavior, DB, and SE scales differed significantly by SOC (P < .001) with moderate to large effect sizes, as predicted by the Transtheoretical Model, which supported the validity of these measures. Successful development and preliminary validation of this 25-item GE instrument provides a basis for assessment as well as development of tailored interventions for college students. Copyright © 2014 Society for Nutrition Education and Behavior. Published by Elsevier Inc. All rights reserved.

Reliability and known-group validity of the Arabic version of the 8-item Morisky Medication Adherence Scale among type 2 diabetes mellitus patients.

PubMed

Ashur, S T; Shamsuddin, K; Shah, S A; Bosseri, S; Morisky, D E

2015-12-13

No validation study has previously been made for the Arabic version of the 8-item Morisky Medication Adherence Scale (MMAS-8(©)) as a measure for medication adherence in diabetes. This study in 2013 tested the reliability and validity of the Arabic MMAS-8 for type 2 diabetes mellitus patients attending a referral centre in Tripoli, Libya. A convenience sample of 103 patients self-completed the questionnaire. Reliability was tested using Cronbach alpha, average inter-item correlation and Spearman-Brown coefficient. Known-group validity was tested by comparing MMAS-8 scores of patients grouped by glycaemic control. The Arabic version showed adequate internal consistency (α = 0.70) and moderate split-half reliability (r = 0.65). Known-group validity was supported as a significant association was found between medication adherence and glycaemic control, with a moderate effect size (ϕc = 0.34). The Arabic version displayed good psychometric properties and could support diabetes research and practice in Arab countries.

Phylogenetic relationships of North American Gomphidae and ...

EPA Pesticide Factsheets

Intrafamilial relationships among clubtail dragonflies (Gomphidae) have been the subject of many morphological studies, but have not yet been systematically evaluated using molecular data. Here we present the first molecular phylogeny of Gomphidae. We include six of the eight subfamilies previously suggested to be valid, and evaluate generic relationships within them. We have included examples of all genera reported from the Nearctic except Phyllocycla. This sample includes all North American species of Ophiogomphus, which has allowed us to explore intrageneric relationships in that genus. Our particular focus is on the closest relatives of the genus Gomphus, especially those North American species groups that have been commonly treated as subgenera of Gomphus. The Gomphus complex is split into additional genera, supported by molecular and morphological evidence: Phanogomphus, Stenogomphurus, Gomphurus and Hylogomphus are here considered to be valid genera. The genus Gomphus, in our restricted sense, does not occur in the western hemisphere; in addition, G. flavipes is transferred to Stylurus. Provide a robust phylogeny of the dragonflies of North America in the family Gomphidae, with implications on number of genera found in North America. This work splits one genus into 3 genera, which may have implications for bioassessment based on macroinvertebrate diversity.

Lowermost mantle anisotropy and deformation along the boundary of the African LLSVP

NASA Astrophysics Data System (ADS)

Lynner, Colton; Long, Maureen D.

2014-05-01

Shear wave splitting of SK(K)S phases is often used to examine upper mantle anisotropy. In specific cases, however, splitting of these phases may reflect anisotropy in the lowermost mantle. Here we present SKS and SKKS splitting measurements for 233 event-station pairs at 34 seismic stations that sample D″ beneath Africa. Of these, 36 pairs show significantly different splitting between the two phases, which likely reflects a contribution from lowermost mantle anisotropy. The vast majority of discrepant pairs sample the boundary of the African large low shear velocity province (LLSVP), which dominates the lower mantle structure beneath this region. In general, we observe little or no splitting of phases that have passed through the LLSVP itself and significant splitting for phases that have sampled the boundary of the LLSVP. We infer that the D″ region just outside the LLSVP boundary is strongly deformed, while its interior remains undeformed (or weakly deformed).

Platelet growth factors from allogeneic platelet-rich plasma for clinical improvement in split-thickness skin graft.

PubMed

Sonker, Atul; Dubey, Anju; Bhatnagar, Ankur; Chaudhary, Rajendra

2015-01-01

Platelets are a source of numerous growth factors which facilitate repair and healing. Thus platelet rich plasma has been increasingly used as a treatment modality in the field of reconstructive surgeries for wound healing. This preliminary study was carried out to explore whether platelet growth factors from platelet rich plasma could be used for enhancement of split thickness skin graft survival. Twenty patients (13 males and 7 females) requiring split thickness skin graft for various clinical reasons were enrolled in the study. Platelet rich plasma was collected by apheresis and frozen at -80° C. It was thawed at room temperature immediately before its intended application. PRP was applied only on one half of the wound, while another half served as control. Patient was followed for 6 weeks. The effect was assessed at first dressing in terms of graft uptake and subsequently as time taken for complete healing. There was 100% uptake of the graft in the area where platelet rich plasma was applied. In the control area, there was complete graft loss in 4 cases, partial loss in 7 cases and complete uptake in 9 cases. This study demonstrated promising results on application of PRP to split thickness skin grafts. Further randomized studies with greater sample size may be undertaken to establish platelet rich plasma as a validated treatment modality.

A global reference database of crowdsourced cropland data collected using the Geo-Wiki platform.

PubMed

Laso Bayas, Juan Carlos; Lesiv, Myroslava; Waldner, François; Schucknecht, Anne; Duerauer, Martina; See, Linda; Fritz, Steffen; Fraisl, Dilek; Moorthy, Inian; McCallum, Ian; Perger, Christoph; Danylo, Olha; Defourny, Pierre; Gallego, Javier; Gilliams, Sven; Akhtar, Ibrar Ul Hassan; Baishya, Swarup Jyoti; Baruah, Mrinal; Bungnamei, Khangsembou; Campos, Alfredo; Changkakati, Trishna; Cipriani, Anna; Das, Krishna; Das, Keemee; Das, Inamani; Davis, Kyle Frankel; Hazarika, Purabi; Johnson, Brian Alan; Malek, Ziga; Molinari, Monia Elisa; Panging, Kripal; Pawe, Chandra Kant; Pérez-Hoyos, Ana; Sahariah, Parag Kumar; Sahariah, Dhrubajyoti; Saikia, Anup; Saikia, Meghna; Schlesinger, Peter; Seidacaru, Elena; Singha, Kuleswar; Wilson, John W

2017-09-26

A global reference data set on cropland was collected through a crowdsourcing campaign using the Geo-Wiki crowdsourcing tool. The campaign lasted three weeks, with over 80 participants from around the world reviewing almost 36,000 sample units, focussing on cropland identification. For quality assessment purposes, two additional data sets are provided. The first is a control set of 1,793 sample locations validated by students trained in satellite image interpretation. This data set was used to assess the quality of the crowd as the campaign progressed. The second data set contains 60 expert validations for additional evaluation of the quality of the contributions. All data sets are split into two parts: the first part shows all areas classified as cropland and the second part shows cropland average per location and user. After further processing, the data presented here might be suitable to validate and compare medium and high resolution cropland maps generated using remote sensing. These could also be used to train classification algorithms for developing new maps of land cover and cropland extent.

A global reference database of crowdsourced cropland data collected using the Geo-Wiki platform

PubMed Central

Laso Bayas, Juan Carlos; Lesiv, Myroslava; Waldner, François; Schucknecht, Anne; Duerauer, Martina; See, Linda; Fritz, Steffen; Fraisl, Dilek; Moorthy, Inian; McCallum, Ian; Perger, Christoph; Danylo, Olha; Defourny, Pierre; Gallego, Javier; Gilliams, Sven; Akhtar, Ibrar ul Hassan; Baishya, Swarup Jyoti; Baruah, Mrinal; Bungnamei, Khangsembou; Campos, Alfredo; Changkakati, Trishna; Cipriani, Anna; Das, Krishna; Das, Keemee; Das, Inamani; Davis, Kyle Frankel; Hazarika, Purabi; Johnson, Brian Alan; Malek, Ziga; Molinari, Monia Elisa; Panging, Kripal; Pawe, Chandra Kant; Pérez-Hoyos, Ana; Sahariah, Parag Kumar; Sahariah, Dhrubajyoti; Saikia, Anup; Saikia, Meghna; Schlesinger, Peter; Seidacaru, Elena; Singha, Kuleswar; Wilson, John W

2017-01-01

A global reference data set on cropland was collected through a crowdsourcing campaign using the Geo-Wiki crowdsourcing tool. The campaign lasted three weeks, with over 80 participants from around the world reviewing almost 36,000 sample units, focussing on cropland identification. For quality assessment purposes, two additional data sets are provided. The first is a control set of 1,793 sample locations validated by students trained in satellite image interpretation. This data set was used to assess the quality of the crowd as the campaign progressed. The second data set contains 60 expert validations for additional evaluation of the quality of the contributions. All data sets are split into two parts: the first part shows all areas classified as cropland and the second part shows cropland average per location and user. After further processing, the data presented here might be suitable to validate and compare medium and high resolution cropland maps generated using remote sensing. These could also be used to train classification algorithms for developing new maps of land cover and cropland extent. PMID:28949323

A global reference database of crowdsourced cropland data collected using the Geo-Wiki platform

NASA Astrophysics Data System (ADS)

Laso Bayas, Juan Carlos; Lesiv, Myroslava; Waldner, François; Schucknecht, Anne; Duerauer, Martina; See, Linda; Fritz, Steffen; Fraisl, Dilek; Moorthy, Inian; McCallum, Ian; Perger, Christoph; Danylo, Olha; Defourny, Pierre; Gallego, Javier; Gilliams, Sven; Akhtar, Ibrar Ul Hassan; Baishya, Swarup Jyoti; Baruah, Mrinal; Bungnamei, Khangsembou; Campos, Alfredo; Changkakati, Trishna; Cipriani, Anna; Das, Krishna; Das, Keemee; Das, Inamani; Davis, Kyle Frankel; Hazarika, Purabi; Johnson, Brian Alan; Malek, Ziga; Molinari, Monia Elisa; Panging, Kripal; Pawe, Chandra Kant; Pérez-Hoyos, Ana; Sahariah, Parag Kumar; Sahariah, Dhrubajyoti; Saikia, Anup; Saikia, Meghna; Schlesinger, Peter; Seidacaru, Elena; Singha, Kuleswar; Wilson, John W.

2017-09-01

A global reference data set on cropland was collected through a crowdsourcing campaign using the Geo-Wiki crowdsourcing tool. The campaign lasted three weeks, with over 80 participants from around the world reviewing almost 36,000 sample units, focussing on cropland identification. For quality assessment purposes, two additional data sets are provided. The first is a control set of 1,793 sample locations validated by students trained in satellite image interpretation. This data set was used to assess the quality of the crowd as the campaign progressed. The second data set contains 60 expert validations for additional evaluation of the quality of the contributions. All data sets are split into two parts: the first part shows all areas classified as cropland and the second part shows cropland average per location and user. After further processing, the data presented here might be suitable to validate and compare medium and high resolution cropland maps generated using remote sensing. These could also be used to train classification algorithms for developing new maps of land cover and cropland extent.

Validation of 31 of the most commonly used immunohistochemical antibodies in cytology prepared using the Cellient(®) automated cell block system.

PubMed

Montgomery, Eric; Gao, Chen; de Luca, Julie; Bower, Jessie; Attwood, Kristropher; Ylagan, Lourdes

2014-12-01

The Cellient(®) cell block system has become available as an alternative, partially automated method to create cell blocks in cytology. We sought to show a validation method for immunohistochemical (IHC) staining on the Cellient cell block system (CCB) in comparison with the formalin fixed paraffin embedded traditional cell block (TCB). Immunohistochemical staining was performed using 31 antibodies on 38 patient samples for a total of 326 slides. Split samples were processed using both methods by following the Cellient(®) manufacturer's recommendations for the Cellient cell block (CCB) and the Histogel method for preparing the traditional cell block (TCB). Interpretation was performed by three pathologists and two cytotechnologists. Immunohistochemical stains were scored as: 0/1+ (negative) and 2/3+ (positive). Inter-rater agreement for each antibody was evaluated for CCB and TCB, as well as the intra-rater agreement between TCB and CCB between observers. Interobserver staining concordance for the TCB was obtained with statistical significance (P < 0.05) in 24 of 31 antibodies. Interobserver staining concordance for the CCB was obtained with statistical significance in 27 of 31 antibodies. Intra-observer staining concordance between TCB and CCB was obtained with statistical significance in 24 of 31 antibodies tested. In conclusions, immunohistochemical stains on cytologic specimens processed by the Cellient system are reliable and concordant with stains performed on the same split samples processed via a formalin fixed-paraffin embedded (FFPE) block. The Cellient system is a welcome adjunct to cytology work-flow by producing cell block material of sufficient quality to allow the use of routine IHC. © 2014 Wiley Periodicals, Inc.

Differences in results of analyses of concurrent and split stream-water samples collected and analyzed by the US Geological Survey and the Illinois Environmental Protection Agency, 1985-91

USGS Publications Warehouse

Melching, C.S.; Coupe, R.H.

1995-01-01

During water years 1985-91, the U.S. Geological Survey (USGS) and the Illinois Environmental Protection Agency (IEPA) cooperated in the collection and analysis of concurrent and split stream-water samples from selected sites in Illinois. Concurrent samples were collected independently by field personnel from each agency at the same time and sent to the IEPA laboratory, whereas the split samples were collected by USGS field personnel and divided into aliquots that were sent to each agency's laboratory for analysis. The water-quality data from these programs were examined by means of the Wilcoxon signed ranks test to identify statistically significant differences between results of the USGS and IEPA analyses. The data sets for constituents and properties identified by the Wilcoxon test as having significant differences were further examined by use of the paired t-test, mean relative percentage difference, and scattergrams to determine if the differences were important. Of the 63 constituents and properties in the concurrent-sample analysis, differences in only 2 (pH and ammonia) were statistically significant and large enough to concern water-quality engineers and planners. Of the 27 constituents and properties in the split-sample analysis, differences in 9 (turbidity, dissolved potassium, ammonia, total phosphorus, dissolved aluminum, dissolved barium, dissolved iron, dissolved manganese, and dissolved nickel) were statistically significant and large enough to con- cern water-quality engineers and planners. The differences in concentration between pairs of the concurrent samples were compared to the precision of the laboratory or field method used. The differences in concentration between pairs of the concurrent samples were compared to the precision of the laboratory or field method used. The differences in concentration between paris of split samples were compared to the precision of the laboratory method used and the interlaboratory precision of measuring a given concentration or property. Consideration of method precision indicated that differences between concurrent samples were insignificant for all concentrations and properties except pH, and that differences between split samples were significant for all concentrations and properties. Consideration of interlaboratory precision indicated that the differences between the split samples were not unusually large. The results for the split samples illustrate the difficulty in obtaining comparable and accurate water-quality data.

Flux-split algorithms for flows with non-equilibrium chemistry and vibrational relaxation

NASA Technical Reports Server (NTRS)

Grossman, B.; Cinnella, P.

1990-01-01

The present consideration of numerical computation methods for gas flows with nonequilibrium chemistry thermodynamics gives attention to an equilibrium model, a general nonequilibrium model, and a simplified model based on vibrational relaxation. Flux-splitting procedures are developed for the fully-coupled inviscid equations encompassing fluid dynamics and both chemical and internal energy-relaxation processes. A fully coupled and implicit large-block structure is presented which embodies novel forms of flux-vector split and flux-difference split algorithms valid for nonequilibrium flow; illustrative high-temperature shock tube and nozzle flow examples are given.

[Reliability and validity of the Chinese version on Alcohol Use Disorders Identification Test].

PubMed

Zhang, C; Yang, G P; Li, Z; Li, X N; Li, Y; Hu, J; Zhang, F Y; Zhang, X J

2017-08-10

Objective: To assess the reliability and validity of the Chinese version on Alcohol Use Disorders Identification Test (AUDIT) among medical students in China and to provide correct way of application on the recommended scales. Methods: An E-questionnaire was developed and sent to medical students in five different colleges. Students were all active volunteers to accept the testings. Cronbach's α and split-half reliability were calculated to evaluate the reliability of AUDIT while content, contract, discriminant and convergent validity were performed to measure the validity of the scales. Results: The overall Cronbach's α of AUDIT was 0.782 and the split-half reliability was 0.711. Data showed that the domain Cronbach's α and split-half reliability were 0.796 and 0.794 for hazardous alcohol use, 0.561 and 0.623 for dependence symptoms, and 0.647 and 0.640 for harmful alcohol use. Results also showed that the content validity index on the levels of items I-CVI) were from 0.83 to 1.00, the content validity index of scale level (S-CVI/UA) was 0.90, content validity index of average scale level (S-CVI/Ave) was 0.99 and the content validity ratios (CVR) were from 0.80 to 1.00. The simplified version of AUDIT supported a presupposed three-factor structure which could explain 61.175% of the total variance revealed through exploratory factor analysis. AUDIT semed to have good convergent and discriminant validity, with the success rate of calibration experiment as 100%. Conclusion: AUDIT showed good reliability and validity among medical students in China thus worth for promotion on its use.

[Validity, reliability, and acceptability of the scale of knowledge, attitude, and behavior of lifestyle intervention in a diabetes high-risk population].

PubMed

Wang, W J; Dong, J; Ren, Z P; Chen, B; He, W; Li, W D; Hao, Z W

2016-07-06

To evaluate the validity, reliability, and acceptability of the scale of knowledge, attitude, and behavior of lifestyle intervention in a diabetes high-risk population (HILKAB), and provide scientific evidence for its usage. By convenient sampling, we selected 406 individuals at high risk for diabetes for survey using the HILKAB. Pearson correlation coefficient, factor analysis, independent sampling, and t-test for high- and low-score groups were used to evaluate the content validity, construct validity, and discriminant validity of the scale. Reliability of the scale was evaluated by internal consistency, which included Cronbach's α coefficient, θ coefficient, Ω coefficient, and split-half reliability. Scale acceptability was evaluated by acceptance rate and completion time of the survey. In this study, 366 questionnaires (90.1%) was qnalified and the completion time was (8.62±2.79) minutes. Scores for knowledge, attitude, and behavior were 10.60±3.73, 26.56±3.58, 17.09±9.74, respectively. The scale had good face validity and content validity. The correlation coefficient of items and the dimension to which they belong was between 0.25 and 0.97, and the correlation coefficient of three dimensions and the entire scale was between 0.64 and 0.91, all with P<0.001. Factor analysis of the scale extracted eight common factors. The cumulative variance contribution rate was 65.23%, thereby reaching the 50% approved standard. Of 30 items there were 29 items with factor loadings ≥0.40, indicating the scale had good construct validity. For the high-score group, scores for knowledge, attitude, and behavior dimensions were 13.89±2.55, 29.56± 2.46, 28.05 ± 2.93, respectively, which were higher than those for the low-score group (7.67 ± 2.78, 23.89 ± 3.35, 6.25 ± 3.13); t-values were 55.14, 119.40, 95.29, respectively, with P<0.001. The scale consisted of three dimensions: knowledge, attitude, and behavior. The Cronbach's α coefficient was between 0.84 and 0.92, the θ coefficient was between 0.85 and 0.96, the Ω coefficient was between 0.90 and 0.94, and the split-half reliability was between 0.77 and 0.95, reaching the 0.70 standard letter. The validity, reliability, and acceptability of the HILKAB scale were satisfactory for use in a population at high risk of diabetes.

Application of the Monte Carlo method for building up models for octanol-water partition coefficient of platinum complexes

NASA Astrophysics Data System (ADS)

Toropov, Andrey A.; Toropova, Alla P.

2018-06-01

Predictive model of logP for Pt(II) and Pt(IV) complexes built up with the Monte Carlo method using the CORAL software has been validated with six different splits into the training and validation sets. The improving of the predictive potential of models for six different splits has been obtained using so-called index of ideality of correlation. The suggested models give possibility to extract molecular features, which cause the increase or vice versa decrease of the logP.

Analysis of selected volatile organic compounds in split and nonsplit swiss cheese samples using selected-ion flow tube mass spectrometry (SIFT-MS).

PubMed

Castada, Hardy Z; Wick, Cheryl; Taylor, Kaitlyn; Harper, W James

2014-04-01

Splits/cracks are recurring product defects that negatively affect the Swiss cheese industry. Investigations to understand the biophysicochemical aspects of these defects, and thus determine preventive measures against their occurrence, are underway. In this study, selected-ion, flow tube mass spectrometry was employed to determine the volatile organic compound (VOC) profiles present in the headspace of split compared with nonsplit cheeses. Two sampling methodologies were employed: split compared with nonsplit cheese vat pair blocks; and comparison of blind, eye, and split segments within cheese blocks. The variability in VOC profiles was examined to evaluate the potential biochemical pathway chemistry differences within and between cheese samples. VOC profile inhomogeneity was most evident in cheeses between factories. Evaluation of biochemical pathways leading to the formation of key VOCs differentiating the split from the blind and eye segments within factories indicated release of additional carbon dioxide by-product. These results suggest a factory-dependent cause of split formation that could develop from varied fermentation pathways in the blind, eye, and split areas within a cheese block. The variability of VOC profiles within and between factories exhibit varied biochemical fermentation pathways that could conceivably be traced back in the making process to identify parameters responsible for split defect. © 2014 Institute of Food Technologists®

Validity and Reliability of the Turkish Chronic Pain Acceptance Questionnaire

PubMed

Akmaz, Hazel Ekin; Uyar, Meltem; Kuzeyli Yıldırım, Yasemin; Akın Korhan, Esra

2018-05-29

Pain acceptance is the process of giving up the struggle with pain and learning to live a worthwhile life despite it. In assessing patients with chronic pain in Turkey, making a diagnosis and tracking the effectiveness of treatment is done with scales that have been translated into Turkish. However, there is as yet no valid and reliable scale in Turkish to assess the acceptance of pain. To validate a Turkish version of the Chronic Pain Acceptance Questionnaire developed by McCracken and colleagues. Methodological and cross sectional study. A simple randomized sampling method was used in selecting the study sample. The sample was composed of 201 patients, more than 10 times the number of items examined for validity and reliability in the study, which totaled 20. A patient identification form, the Chronic Pain Acceptance Questionnaire, and the Brief Pain Inventory were used to collect data. Data were collected by face-to-face interviews. In the validity testing, the content validity index was used to evaluate linguistic equivalence, content validity, construct validity, and expert views. In reliability testing of the scale, Cronbach’s α coefficient was calculated, and item analysis and split-test reliability methods were used. Principal component analysis and varimax rotation were used in factor analysis and to examine factor structure for construct concept validity. The item analysis established that the scale, all items, and item-total correlations were satisfactory. The mean total score of the scale was 21.78. The internal consistency coefficient was 0.94, and the correlation between the two halves of the scale was 0.89. The Chronic Pain Acceptance Questionnaire, which is intended to be used in Turkey upon confirmation of its validity and reliability, is an evaluation instrument with sufficient validity and reliability, and it can be reliably used to examine patients’ acceptance of chronic pain.

Validity and Reliability of the Turkish Chronic Pain Acceptance Questionnaire

PubMed Central

Akmaz, Hazel Ekin; Uyar, Meltem; Kuzeyli Yıldırım, Yasemin; Akın Korhan, Esra

2018-01-01

Background: Pain acceptance is the process of giving up the struggle with pain and learning to live a worthwhile life despite it. In assessing patients with chronic pain in Turkey, making a diagnosis and tracking the effectiveness of treatment is done with scales that have been translated into Turkish. However, there is as yet no valid and reliable scale in Turkish to assess the acceptance of pain. Aims: To validate a Turkish version of the Chronic Pain Acceptance Questionnaire developed by McCracken and colleagues. Study Design: Methodological and cross sectional study. Methods: A simple randomized sampling method was used in selecting the study sample. The sample was composed of 201 patients, more than 10 times the number of items examined for validity and reliability in the study, which totaled 20. A patient identification form, the Chronic Pain Acceptance Questionnaire, and the Brief Pain Inventory were used to collect data. Data were collected by face-to-face interviews. In the validity testing, the content validity index was used to evaluate linguistic equivalence, content validity, construct validity, and expert views. In reliability testing of the scale, Cronbach’s α coefficient was calculated, and item analysis and split-test reliability methods were used. Principal component analysis and varimax rotation were used in factor analysis and to examine factor structure for construct concept validity. Results: The item analysis established that the scale, all items, and item-total correlations were satisfactory. The mean total score of the scale was 21.78. The internal consistency coefficient was 0.94, and the correlation between the two halves of the scale was 0.89. Conclusion: The Chronic Pain Acceptance Questionnaire, which is intended to be used in Turkey upon confirmation of its validity and reliability, is an evaluation instrument with sufficient validity and reliability, and it can be reliably used to examine patients’ acceptance of chronic pain. PMID:29843496

Creating ensembles of oblique decision trees with evolutionary algorithms and sampling

DOEpatents

Cantu-Paz, Erick [Oakland, CA; Kamath, Chandrika [Tracy, CA

2006-06-13

A decision tree system that is part of a parallel object-oriented pattern recognition system, which in turn is part of an object oriented data mining system. A decision tree process includes the step of reading the data. If necessary, the data is sorted. A potential split of the data is evaluated according to some criterion. An initial split of the data is determined. The final split of the data is determined using evolutionary algorithms and statistical sampling techniques. The data is split. Multiple decision trees are combined in ensembles.

The Outpatient Experience Questionnaire of comprehensive public hospital in China: development, validity and reliability.

PubMed

Hu, Yinhuan; Zhang, Zixia; Xie, Jinzhu; Wang, Guanping

2017-02-01

The objective of this study is to describe the development of the Outpatient Experience Questionnaire (OPEQ) and to assess the validity and reliability of the scale. Literature review, patient interviews, Delphi method and Cross-sectional validation survey. Six comprehensive public hospitals in China. The survey was carried out on a sample of 600 outpatients. Acceptability of the questionnaire was assessed according to the overall response rate, item non-response rate and the average completion time. Correlation coefficients and confirmatory factor analysis were used to test construct validity. Delphi method was used to assess the content validity of the questionnaire. Cronbach's coefficient alpha and split-half reliability coefficient were used to estimate the internal reliability of the questionnaire. The overall response rate was 97.2% and the item non-response rate ranged from 0% to 0.3%. The mean completion time was 6 min. The Spearman correlations of item-total score ranged from 0.466 to 0.765. The results of confirmatory factor analysis showed that all items had factor loadings above 0.40 and the dimension intercorrelation ranged from 0.449 to 0.773, the goodness of fit of the questionnaire was reasonable. The overall authority grade of expert consultation was 0.80 and Kendall's coefficient of concordance W was 0.186. The Cronbach's coefficients alpha of six dimensions ranged from 0.708 to 0.895, the split-half reliability coefficient (Spearman-Brown coefficient) was 0.969. The OPEQ is a promising instrument covering the most important aspects which influence outpatient experiences of comprehensive public hospital in China. It has good evidence for acceptability, validity and reliability. © The Author 2016. Published by Oxford University Press in association with the International Society for Quality in Health Care. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com

Validation of a short questionnaire to assess mothers' perception of workplace breastfeeding support.

PubMed

Bai, Yeon; Peng, C-Y Joanne; Fly, Alyce D

2008-07-01

The purpose of this study was to create and establish the validity of a short questionnaire to measure mothers' perceived support for breastfeeding from the workplace. The items in the workplace breastfeeding support scale (WBSS) were derived from a literature review. The scale was self-administered in central Indiana during the fall of 2005 to a convenience sample of 66 volunteers who were primiparous, 6 to 12 months postpartum, worked outside home, and had initiated breastfeeding prior to the survey. Internal consistency (alpha) and split-half reliability (r) tests and a factor analysis were done to establish reliability and construct validity of the scale. The WBSS showed acceptable reliability (alpha=.77, r=0.86). Content validity was established by review using a panel of experts. Four distinct constructs of the scale were identified that accounted for 62.1% of the total variability of the scale: technical, environmental, facility, and peer support, thus establishing construct validity of the scale. Lactation consultants and worksite lactation program planners can use the WBSS to help mothers returning to work and to assess the needs for improvement of support programs.

Sampling for mercury at subnanogram per litre concentrations for load estimation in rivers

USGS Publications Warehouse

Colman, J.A.; Breault, R.F.

2000-01-01

Estimation of constituent loads in streams requires collection of stream samples that are representative of constituent concentrations, that is, composites of isokinetic multiple verticals collected along a stream transect. An all-Teflon isokinetic sampler (DH-81) cleaned in 75??C, 4 N HCl was tested using blank, split, and replicate samples to assess systematic and random sample contamination by mercury species. Mean mercury concentrations in field-equipment blanks were low: 0.135 ng??L-1 for total mercury (??Hg) and 0.0086 ng??L-1 for monomethyl mercury (MeHg). Mean square errors (MSE) for ??Hg and MeHg duplicate samples collected at eight sampling stations were not statistically different from MSE of samples split in the laboratory, which represent the analytical and splitting error. Low fieldblank concentrations and statistically equal duplicate- and split-sample MSE values indicate that no measurable contamination was occurring during sampling. Standard deviations associated with example mercury load estimations were four to five times larger, on a relative basis, than standard deviations calculated from duplicate samples, indicating that error of the load determination was primarily a function of the loading model used, not of sampling or analytical methods.

Using the split Hopkinson pressure bar to validate material models.

PubMed

Church, Philip; Cornish, Rory; Cullis, Ian; Gould, Peter; Lewtas, Ian

2014-08-28

This paper gives a discussion of the use of the split-Hopkinson bar with particular reference to the requirements of materials modelling at QinetiQ. This is to deploy validated material models for numerical simulations that are physically based and have as little characterization overhead as possible. In order to have confidence that the models have a wide range of applicability, this means, at most, characterizing the models at low rate and then validating them at high rate. The split Hopkinson pressure bar (SHPB) is ideal for this purpose. It is also a very useful tool for analysing material behaviour under non-shock wave loading. This means understanding the output of the test and developing techniques for reliable comparison of simulations with SHPB data. For materials other than metals comparison with an output stress v strain curve is not sufficient as the assumptions built into the classical analysis are generally violated. The method described in this paper compares the simulations with as much validation data as can be derived from deployed instrumentation including the raw strain gauge data on the input and output bars, which avoids any assumptions about stress equilibrium. One has to take into account Pochhammer-Chree oscillations and their effect on the specimen and recognize that this is itself also a valuable validation test of the material model. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

Psychometric Evaluation of the Summary of Diabetes Self-Care Activities-Arabic (SDSCA-Arabic): Translation and Analysis Process.

PubMed

AlJohani, Khalid A; Kendall, Garth E; Snider, Paul D

2016-01-01

To translate and examine the psychometric properties of the Arabic version of the Summary of Diabetes Self-Care Activities. An instrument translation and validation study. A total of 243 participants (33 first sample and 210 second sample) diagnosed with type 2 diabetes mellitus were recruited from four primary health care centers in Saudi Arabia. The study was guided by the World Health Organization guidelines for translation and validation of instrument. Translation indicators showed satisfactory outcomes for each included process in the forward-translation, an expert panel, and back-translation stages. Reliability and validity outcomes were as follows: test-retest, r = .912 and p < .001; split-half = .9; and Cronbach's alpha (α) = .76. The alpha scores for the subscales were as follows: diet, .89; exercise, .83; blood glucose testing, .92; and foot care, .77. Principal component analysis revealed the presence of four components with eigenvalues greater than 1.0, explaining 34.4, 16.4, 15.4, and 11.2% of the variance in everyday practices for these items, respectively (accumulated = 77.1%). The translation and validation processes revealed acceptable psychometric properties. The instrument could evaluate diabetes self-care in Saudi Arabia and has the potential to be used in other Arabic-speaking populations. © The Author(s) 2014.

Assessment of dietary restraint: psychometric properties of the revised restraint scale in Hong Kong adolescents.

PubMed

Mak, Kwok-Kei; Lai, Ching-Man

2012-06-01

The psychometric properties of the Revised Restraint Scale (RRS) have been well established in western populations but not in Chinese adolescents. This study investigated the psychometric properties of RRS and its validity in different subgroups for Hong Kong Chinese adolescents. In 2007, 909 Hong Kong students aged 12 to 18 years (55.3% boys) completed a questionnaire including demographic items, RRS, Eating Attitudes Test (EAT-26), and Motivation for Eating Scale (MFES)-physical. Moreover, subjects' height and weight were measured. To examine the factor structure of RRS, the whole sample was randomly split into two groups (sample 1: N=454 and sample 2: N=455) for exploratory factor analysis (EFA) and confirmatory factor analysis (CFA), respectively. Convergent and discriminant validity of RRS were investigated by correlating the RRS with EAT-26 and MFES-physical. Multigroup CFA was conducted to test the three-factor model of RRS in different sex, age, and weight status subgroups. Results of EFA for sample 1 revealed three strongly correlated factors for the RRS construct, and were supported by the CFA results in sample 2. Multigroup CFA further suggested that the three-factor model of RRS was stable across sex, age, and weight status subgroups. A new three-factor model is proposed for Hong Kong adolescents in this study. In general, RRS is a reliable and valid measure of restrained eating for adolescents, regardless of sex, age, and weight status.

Development of a patient reported outcome scale for fatigue in multiple sclerosis: The Neurological Fatigue Index (NFI-MS)

PubMed Central

2010-01-01

Background Fatigue is a common and debilitating symptom in multiple sclerosis (MS). Best-practice guidelines suggest that health services should repeatedly assess fatigue in persons with MS. Several fatigue scales are available but concern has been expressed about their validity. The objective of this study was to examine the reliability and validity of a new scale for MS fatigue, the Neurological Fatigue Index (NFI-MS). Methods Qualitative analysis of 40 MS patient interviews had previously contributed to a coherent definition of fatigue, and a potential 52 item set representing the salient themes. A draft questionnaire was mailed out to 1223 people with MS, and the resulting data subjected to both factor and Rasch analysis. Results Data from 635 (51.9% response) respondents were split randomly into an 'evaluation' and 'validation' sample. Exploratory factor analysis identified four potential subscales: 'physical', 'cognitive', 'relief by diurnal sleep or rest' and 'abnormal nocturnal sleep and sleepiness'. Rasch analysis led to further item reduction and the generation of a Summary scale comprising items from the Physical and Cognitive subscales. The scales were shown to fit Rasch model expectations, across both the evaluation and validation samples. Conclusion A simple 10-item Summary scale, together with scales measuring the physical and cognitive components of fatigue, were validated for MS fatigue. PMID:20152031

Gram-negative and -positive bacteria differentiation in blood culture samples by headspace volatile compound analysis.

PubMed

Dolch, Michael E; Janitza, Silke; Boulesteix, Anne-Laure; Graßmann-Lichtenauer, Carola; Praun, Siegfried; Denzer, Wolfgang; Schelling, Gustav; Schubert, Sören

2016-12-01

Identification of microorganisms in positive blood cultures still relies on standard techniques such as Gram staining followed by culturing with definite microorganism identification. Alternatively, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry or the analysis of headspace volatile compound (VC) composition produced by cultures can help to differentiate between microorganisms under experimental conditions. This study assessed the efficacy of volatile compound based microorganism differentiation into Gram-negatives and -positives in unselected positive blood culture samples from patients. Headspace gas samples of positive blood culture samples were transferred to sterilized, sealed, and evacuated 20 ml glass vials and stored at -30 °C until batch analysis. Headspace gas VC content analysis was carried out via an auto sampler connected to an ion-molecule reaction mass spectrometer (IMR-MS). Measurements covered a mass range from 16 to 135 u including CO2, H2, N2, and O2. Prediction rules for microorganism identification based on VC composition were derived using a training data set and evaluated using a validation data set within a random split validation procedure. One-hundred-fifty-two aerobic samples growing 27 Gram-negatives, 106 Gram-positives, and 19 fungi and 130 anaerobic samples growing 37 Gram-negatives, 91 Gram-positives, and two fungi were analysed. In anaerobic samples, ten discriminators were identified by the random forest method allowing for bacteria differentiation into Gram-negative and -positive (error rate: 16.7 % in validation data set). For aerobic samples the error rate was not better than random. In anaerobic blood culture samples of patients IMR-MS based headspace VC composition analysis facilitates bacteria differentiation into Gram-negative and -positive.

Enzyme-linked small-molecule detection using split aptamer ligation.

PubMed

Sharma, Ashwani K; Kent, Alexandra D; Heemstra, Jennifer M

2012-07-17

Here we report an aptamer-based analogue of the widely used sandwich enzyme-linked immunosorbent assay (ELISA). This assay utilizes the cocaine split aptamer, which is comprised of two DNA strands that only assemble in the presence of the target small molecule. One split aptamer fragment is immobilized on a microplate, then a test sample is added containing the second split aptamer fragment. If cocaine is present in the test sample, it directs assembly of the split aptamer and promotes a chemical ligation between azide and cyclooctyne functional groups appended to the termini of the split aptamer fragments. Ligation results in covalent attachment of biotin to the microplate and provides a colorimetric output upon conjugation to streptavidin-horseradish peroxidase. Using this assay, we demonstrate detection of cocaine at concentrations of 100 nM-100 μM in buffer and 1-100 μM human blood serum. The detection limit of 1 μM in serum represents an improvement of two orders of magnitude over previously reported split aptamer-based sensors and highlights the utility of covalently trapping split aptamer assembly events.

Cost-Effective Mapping of Benthic Habitats in Inland Reservoirs through Split-Beam Sonar, Indicator Kriging, and Historical Geologic Data

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

Venteris, Erik R.; May, Cassandra

2014-04-23

Because bottom substrate composition is an important control on the temporal and spatial location of the aquatic community, accurate maps of benthic habitats of inland lakes and reservoirs provide valuable information to managers, recreational users, and scientists. Therefore, we collected vertical, split-beam sonar data (roughness [E1], hardness [E2], and bathymetry) and sediment samples to make such maps. Statistical calibration between sonar parameters and sediment classes was problematic because the E1:E2 ratios for soft (muck and clay) sediments overlapped a lower and narrower range for hard (gravel) substrates. Thus, we used indicator kriging (IK) to map the probability that unsampled locationsmore » did not contain coarse sediments. To overcome the calibration issue we tested proxies for the natural processes and anthropogenic history of the reservoir as potential predictive variables. Of these, a geologic map proved to be the most useful. The central alluvial valley and mudflats contained mainly muck and organic-rich clays. The surrounding glacial till and shale bedrock uplands contained mainly poorly sorted gravels. Anomalies in the sonar data suggested that the organic-rich sediments also contained trapped gases, presenting additional interpretive issues for the mapping. We extended the capability of inexpensive split-beam sonar units through the incorporation of historic geologic maps and other records as well as validation with dredge samples. Through the integration of information from multiple data sets, were able to objectively identify bottom substrate and provide reservoir users with an accurate map of available benthic habitat.« less

Cost-Effective Mapping of Benthic Habitats in Inland Reservoirs through Split-Beam Sonar, Indicator Kriging, and Historical Geologic Data

PubMed Central

Venteris, Erik R.; May, Cassandra J.

2014-01-01

Because bottom substrate composition is an important control on the temporal and spatial location of the aquatic community, accurate maps of benthic habitats of inland lakes and reservoirs provide valuable information to managers, recreational users, and scientists. Therefore, we collected vertical, split-beam sonar data (roughness [E1], hardness [E2], and bathymetry) and sediment samples to make such maps. Statistical calibration between sonar parameters and sediment classes was problematic because the E1:E2 ratios for soft (muck and clay) sediments overlapped a lower and narrower range for hard (gravel) substrates. Thus, we used indicator kriging (IK) to map the probability that unsampled locations did not contain coarse sediments. To overcome the calibration issue we tested proxies for the natural processes and anthropogenic history of the reservoir as potential predictive variables. Of these, a geologic map proved to be the most useful. The central alluvial valley and mudflats contained mainly muck and organic-rich clays. The surrounding glacial till and shale bedrock uplands contained mainly poorly sorted gravels. Anomalies in the sonar data suggested that the organic-rich sediments also contained trapped gases, presenting additional interpretive issues for the mapping. We extended the capability of inexpensive split-beam sonar units through the incorporation of historic geologic maps and other records as well as validation with dredge samples. Through the integration of information from multiple data sets, were able to objectively identify bottom substrate and provide reservoir users with an accurate map of available benthic habitat. PMID:24759834

Cost-effective mapping of benthic habitats in inland reservoirs through split-beam sonar, indicator kriging, and historical geologic data.

PubMed

Venteris, Erik R; May, Cassandra J

2014-01-01

Because bottom substrate composition is an important control on the temporal and spatial location of the aquatic community, accurate maps of benthic habitats of inland lakes and reservoirs provide valuable information to managers, recreational users, and scientists. Therefore, we collected vertical, split-beam sonar data (roughness [E1], hardness [E2], and bathymetry) and sediment samples to make such maps. Statistical calibration between sonar parameters and sediment classes was problematic because the E1:E2 ratios for soft (muck and clay) sediments overlapped a lower and narrower range for hard (gravel) substrates. Thus, we used indicator kriging (IK) to map the probability that unsampled locations did not contain coarse sediments. To overcome the calibration issue we tested proxies for the natural processes and anthropogenic history of the reservoir as potential predictive variables. Of these, a geologic map proved to be the most useful. The central alluvial valley and mudflats contained mainly muck and organic-rich clays. The surrounding glacial till and shale bedrock uplands contained mainly poorly sorted gravels. Anomalies in the sonar data suggested that the organic-rich sediments also contained trapped gases, presenting additional interpretive issues for the mapping. We extended the capability of inexpensive split-beam sonar units through the incorporation of historic geologic maps and other records as well as validation with dredge samples. Through the integration of information from multiple data sets, were able to objectively identify bottom substrate and provide reservoir users with an accurate map of available benthic habitat.

Determining optimal parameters of the self-referent encoding task: A large-scale examination of self-referent cognition and depression.

PubMed

Dainer-Best, Justin; Lee, Hae Yeon; Shumake, Jason D; Yeager, David S; Beevers, Christopher G

2018-06-07

Although the self-referent encoding task (SRET) is commonly used to measure self-referent cognition in depression, many different SRET metrics can be obtained. The current study used best subsets regression with cross-validation and independent test samples to identify the SRET metrics most reliably associated with depression symptoms in three large samples: a college student sample (n = 572), a sample of adults from Amazon Mechanical Turk (n = 293), and an adolescent sample from a school field study (n = 408). Across all 3 samples, SRET metrics associated most strongly with depression severity included number of words endorsed as self-descriptive and rate of accumulation of information required to decide whether adjectives were self-descriptive (i.e., drift rate). These metrics had strong intratask and split-half reliability and high test-retest reliability across a 1-week period. Recall of SRET stimuli and traditional reaction time (RT) metrics were not robustly associated with depression severity. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

The Response of Simple Polymer Structures Under Dynamic Loading

NASA Astrophysics Data System (ADS)

Proud, William; Ellison, Kay; Yapp, Su; Cole, Cloe; Galimberti, Stefano; Institute of Shock Physics Team

2017-06-01

The dynamic response of polymeric materials has been widely studied with the effects of degree of crystallinity, strain rate, temperature and sample size being commonly reported. This study uses a simple PMMA structure, a right cylindrical sample, with structural features such as holes. The features are added an varied in a systematic fashion. Samples were dynamically loaded using a Split Hopkinson Pressure Bar up to failure. The resulting stress-strain curves are presented showing the change in sample response. The strain to failure is shown to increase initially with the presence of holes, while failure stress is relatively unaffected. The fracture patterns seen in the failed samples change, with tensile cracks, Hertzian cones, shear effects being dominant for different holes sizes and geometries. The sample were prepared by laser cutting and checked for residual stress before experiment. The data is used to validate predictive model predictions where material, structure and damage are included.. The Institute of Shock Physics acknowledges the support of Imperial College London and the Atomic Weapons Establishment.

A unified bond theory, probabilistic meso-scale modeling, and experimental validation of deformed steel rebar in normal strength concrete

NASA Astrophysics Data System (ADS)

Wu, Chenglin

Bond between deformed rebar and concrete is affected by rebar deformation pattern, concrete properties, concrete confinement, and rebar-concrete interfacial properties. Two distinct groups of bond models were traditionally developed based on the dominant effects of concrete splitting and near-interface shear-off failures. Their accuracy highly depended upon the test data sets selected in analysis and calibration. In this study, a unified bond model is proposed and developed based on an analogy to the indentation problem around the rib front of deformed rebar. This mechanics-based model can take into account the combined effect of concrete splitting and interface shear-off failures, resulting in average bond strengths for all practical scenarios. To understand the fracture process associated with bond failure, a probabilistic meso-scale model of concrete is proposed and its sensitivity to interface and confinement strengths are investigated. Both the mechanical and finite element models are validated with the available test data sets and are superior to existing models in prediction of average bond strength (< 6% error) and crack spacing (< 6% error). The validated bond model is applied to derive various interrelations among concrete crushing, concrete splitting, interfacial behavior, and the rib spacing-to-height ratio of deformed rebar. It can accurately predict the transition of failure modes from concrete splitting to rebar pullout and predict the effect of rebar surface characteristics as the rib spacing-to-height ratio increases. Based on the unified theory, a global bond model is proposed and developed by introducing bond-slip laws, and validated with testing of concrete beams with spliced reinforcement, achieving a load capacity prediction error of less than 26%. The optimal rebar parameters and concrete cover in structural designs can be derived from this study.

Split-plot microarray experiments: issues of design, power and sample size.

PubMed

Tsai, Pi-Wen; Lee, Mei-Ling Ting

2005-01-01

This article focuses on microarray experiments with two or more factors in which treatment combinations of the factors corresponding to the samples paired together onto arrays are not completely random. A main effect of one (or more) factor(s) is confounded with arrays (the experimental blocks). This is called a split-plot microarray experiment. We utilise an analysis of variance (ANOVA) model to assess differentially expressed genes for between-array and within-array comparisons that are generic under a split-plot microarray experiment. Instead of standard t- or F-test statistics that rely on mean square errors of the ANOVA model, we use a robust method, referred to as 'a pooled percentile estimator', to identify genes that are differentially expressed across different treatment conditions. We illustrate the design and analysis of split-plot microarray experiments based on a case application described by Jin et al. A brief discussion of power and sample size for split-plot microarray experiments is also presented.

Data for a regional approach to the development of an effects-based nutrient criterion for wadable streams

USGS Publications Warehouse

Crawford, J. Kent; Loper, Connie A.; Beaman, Joseph R.; Soehl, Anna G.; Brown, Will S.

2007-01-01

States are required by the U.S. Environmental Protection Agency to establish nutrient criteria (concentrations of nutrients above which water quality is deteriorated) as part of their water-quality regulations. A study of wadable streams in the Mid-Atlantic Region was undertaken by the U.S. Geological Survey, the U.S. Environmental Protection Agency, and the Maryland Department of the Environment, with assistance from the Pennsylvania Department of Environmental Protection, to help define current concentrations of nutrients in streams with the goal of associating different nutrient-concentration levels with their effects on water quality. During the summers of 2004 and 2005, diel concentrations of dissolved oxygen, nutrient concentrations, concentrations of chlorophyll a in attached algae, and algal-community structure were measured at 46 stream sites in Maryland, Pennsylvania, Virginia, and West Virginia. Data from this work can be used by individual state agencies to define nutrient criteria. Quality-control measures for the study included submitting blank samples, duplicate samples, and reference samples for analysis of nutrients, total organic carbon, chlorophyll a, and algal biomass. Duplicate and split samples were submitted for periphyton identifications. Three periphyton split samples were sent to an independent lab for a check on periphyton identifications. Neither total organic carbon nor nutrients were detected in blank samples. Concentrations of nutrients and total organic carbon were similar for most duplicate sample pairs, with the exception of a duplicate pair from Western Run. Concentrations of ammonia plus organic nitrogen for this duplicate pair differed by as much as 34 percent. Total organic carbon for the duplicate pair from Western Run differed by 102 percent. The U.S. Geological Survey National Water Quality Laboratory performance on the only valid reference sample submitted was excellent; the relative percent difference values were no larger than 5 percent for any constituent analyzed. For periphyton identifications, duplicate samples had Jaccard Coefficient of Community values slightly greater than 0.5. This indicates the periphyton sampling protocol used provided a sample that was only moderately reproducible. Jaccard Coefficients for three periphyton samples split between two independent labs were 0.2, 0.11, and 0.08. These very low values suggest a poor concurrence on species identifications performed by the two labs. As a result of these quality-control samples, the slides prepared for diatom identifications were sent to the Academy of Natural Sciences for re-identification. Caution is urged when interpreting periphyton-community information from this study. This report and the raw data from the study are available online at http://pubs.usgs.gov/ds257

The development and validation of the Youth Actuarial Care Needs Assessment Tool for Non-Offenders (Y-ACNAT-NO).

PubMed

Assink, Mark; van der Put, Claudia E; Oort, Frans J; Stams, Geert Jan J M

2015-03-04

In The Netherlands, police officers not only come into contact with juvenile offenders, but also with a large number of juveniles who were involved in a criminal offense, but not in the role of a suspect (i.e., juvenile non-offenders). Until now, no valid and reliable instrument was available that can be used by Dutch police officers for estimating the risk for future care needs of juvenile non-offenders. In the present study, the Youth Actuarial Care Needs Assessment Tool for Non-Offenders (Y-ACNAT-NO) was developed for predicting the risk for future care needs that consisted of (1) a future supervision order as imposed by a juvenile court judge and (2) future worrisome incidents involving child abuse, domestic violence/strife, and/or sexual offensive behavior at the juvenile's living address (i.e., problems in the child-rearing environment). Police records of 3,200 juveniles were retrieved from the Dutch police registration system after which the sample was randomly split in a construction (n = 1,549) and validation sample (n = 1,651). The Y-ACNAT-NO was developed by performing an Exhaustive CHAID analysis using the construction sample. The predictive validity of the instrument was examined in the validation sample by calculating several performance indicators that assess discrimination and calibration. The CHAID output yielded an instrument that consisted of six variables and eleven different risk groups. The risk for future care needs ranged from 0.06 in the lowest risk group to 0.83 in the highest risk group. The AUC value in the validation sample was .764 (95% CI [.743, .784]) and Sander's calibration score indicated an average assessment error of 3.74% in risk estimates per risk category. The Y-ACNAT-NO is the first instrument that can be used by Dutch police officers for estimating the risk for future care needs of juvenile non-offenders. The predictive validity of the Y-ACNAT-NO in terms of discrimination and calibration was sufficient to justify its use as an initial screening instrument when a decision is needed about referring a juvenile for further assessment of care needs.

[Reliability and validity of Driving Anger Scale in professional drivers in China].

PubMed

Li, Z; Yang, Y M; Zhang, C; Li, Y; Hu, J; Gao, L W; Zhou, Y X; Zhang, X J

2017-11-10

Objective: To assess the reliability and validity of the Chinese version of Driving Anger Scale (DAS) in professional drivers in China and provide a scientific basis for the application of the scale in drivers in China. Methods: Professional drivers, including taxi drivers, bus drivers, truck drivers and school bus drivers, were selected to complete the questionnaire. Cronbach's α and split-half reliability were calculated to evaluate the reliability of DAS, and content, contract, discriminant and convergent validity were performed to measure the validity of the scale. Results: The overall Cronbach's α of DAS was 0.934 and the split-half reliability was 0.874. The correlation coefficient of each subscale with the total scale was 0.639-0.922. The simplified version of DAS supported a presupposed six-factor structure, explaining 56.371% of the total variance revealed by exploratory factor analysis. The DAS had good convergent and discriminant validity, with the success rate of calibration experiment of 100%. Conclusion: DAS has a good reliability and validity in professional drivers in China, and the use of DAS is worth promoting in divers.

Calibration and validation of a general infiltration model

NASA Astrophysics Data System (ADS)

Mishra, Surendra Kumar; Ranjan Kumar, Shashi; Singh, Vijay P.

1999-08-01

A general infiltration model proposed by Singh and Yu (1990) was calibrated and validated using a split sampling approach for 191 sets of infiltration data observed in the states of Minnesota and Georgia in the USA. Of the five model parameters, fc (the final infiltration rate), So (the available storage space) and exponent n were found to be more predictable than the other two parameters: m (exponent) and a (proportionality factor). A critical examination of the general model revealed that it is related to the Soil Conservation Service (1956) curve number (SCS-CN) method and its parameter So is equivalent to the potential maximum retention of the SCS-CN method and is, in turn, found to be a function of soil sorptivity and hydraulic conductivity. The general model was found to describe infiltration rate with time varying curve number.

Measuring cardiac waste: the premier cardiac waste measures.

PubMed

Lowe, Timothy J; Partovian, Chohreh; Kroch, Eugene; Martin, John; Bankowitz, Richard

2014-01-01

The authors developed 8 measures of waste associated with cardiac procedures to assist hospitals in comparing their performance with peer facilities. Measure selection was based on review of the research literature, clinical guidelines, and consultation with key stakeholders. Development and validation used the data from 261 hospitals in a split-sample design. Measures were risk adjusted using Premier's CareScience methodologies or mean peer value based on Medicare Severity Diagnosis-Related Group assignment. High variability was found in resource utilization across facilities. Validation of the measures using item-to-total correlations (range = 0.27-0.78), Cronbach α (.88), and Spearman rank correlation (0.92) showed high reliability and discriminatory power. Because of the level of variability observed among hospitals, this study suggests that there is opportunity for facilities to design successful waste reduction programs targeting cardiac-device procedures.

Integrated Primary Care Readiness and Behaviors Scale: Development and validation in behavioral health professionals.

PubMed

Blaney, Cerissa L; Redding, Colleen A; Paiva, Andrea L; Rossi, Joseph S; Prochaska, James O; Blissmer, Bryan; Burditt, Caitlin T; Nash, Justin M; Bayley, Keri Dotson

2018-03-01

Although integrated primary care (IPC) is growing, several barriers remain. Better understanding of behavioral health professionals' (BHPs') readiness for and engagement in IPC behaviors could improve IPC research and training. This study developed measures of IPC behaviors and stage of change. The sample included 319 licensed, practicing BHPs with a range of interests and experience with IPC. Sequential measurement development procedures, with split-half cross-validation were conducted. Exploratory principal components analyses (N = 152) and confirmatory factor analyses (N = 167) yielded a 12-item scale with 2 factors: consultation/practice management (CPM) and intervention/knowledge (IK). A higher-order Integrated Primary Care Behavior Scale (IPCBS) model showed good fit to the data, and excellent internal consistencies. The multivariate analysis of variance (MANOVA) on the IPCBS demonstrated significant large-sized differences across stage and behavior groups. The IPCBS demonstrated good psychometric properties and external validation, advancing research, education, and training for IPC practice. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Application of particle splitting method for both hydrostatic and hydrodynamic cases in SPH

NASA Astrophysics Data System (ADS)

Liu, W. T.; Sun, P. N.; Ming, F. R.; Zhang, A. M.

2018-01-01

Smoothed particle hydrodynamics (SPH) method with numerical diffusive terms shows satisfactory stability and accuracy in some violent fluid-solid interaction problems. However, in most simulations, uniform particle distributions are used and the multi-resolution, which can obviously improve the local accuracy and the overall computational efficiency, has seldom been applied. In this paper, a dynamic particle splitting method is applied and it allows for the simulation of both hydrostatic and hydrodynamic problems. The splitting algorithm is that, when a coarse (mother) particle enters the splitting region, it will be split into four daughter particles, which inherit the physical parameters of the mother particle. In the particle splitting process, conservations of mass, momentum and energy are ensured. Based on the error analysis, the splitting technique is designed to allow the optimal accuracy at the interface between the coarse and refined particles and this is particularly important in the simulation of hydrostatic cases. Finally, the scheme is validated by five basic cases, which demonstrate that the present SPH model with a particle splitting technique is of high accuracy and efficiency and is capable for the simulation of a wide range of hydrodynamic problems.

Can quantile mapping improve precipitation extremes from regional climate models?

NASA Astrophysics Data System (ADS)

Tani, Satyanarayana; Gobiet, Andreas

2015-04-01

The ability of quantile mapping to accurately bias correct regard to precipitation extremes is investigated in this study. We developed new methods by extending standard quantile mapping (QMα) to improve the quality of bias corrected extreme precipitation events as simulated by regional climate model (RCM) output. The new QM version (QMβ) was developed by combining parametric and nonparametric bias correction methods. The new nonparametric method is tested with and without a controlling shape parameter (Qmβ1 and Qmβ0, respectively). Bias corrections are applied on hindcast simulations for a small ensemble of RCMs at six different locations over Europe. We examined the quality of the extremes through split sample and cross validation approaches of these three bias correction methods. This split-sample approach mimics the application to future climate scenarios. A cross validation framework with particular focus on new extremes was developed. Error characteristics, q-q plots and Mean Absolute Error (MAEx) skill scores are used for evaluation. We demonstrate the unstable behaviour of correction function at higher quantiles with QMα, whereas the correction functions with for QMβ0 and QMβ1 are smoother, with QMβ1 providing the most reasonable correction values. The result from q-q plots demonstrates that, all bias correction methods are capable of producing new extremes but QMβ1 reproduces new extremes with low biases in all seasons compared to QMα, QMβ0. Our results clearly demonstrate the inherent limitations of empirical bias correction methods employed for extremes, particularly new extremes, and our findings reveals that the new bias correction method (Qmß1) produces more reliable climate scenarios for new extremes. These findings present a methodology that can better capture future extreme precipitation events, which is necessary to improve regional climate change impact studies.

Representativeness of laboratory sampling procedures for the analysis of trace metals in soil.

PubMed

Dubé, Jean-Sébastien; Boudreault, Jean-Philippe; Bost, Régis; Sona, Mirela; Duhaime, François; Éthier, Yannic

2015-08-01

This study was conducted to assess the representativeness of laboratory sampling protocols for purposes of trace metal analysis in soil. Five laboratory protocols were compared, including conventional grab sampling, to assess the influence of sectorial splitting, sieving, and grinding on measured trace metal concentrations and their variability. It was concluded that grinding was the most important factor in controlling the variability of trace metal concentrations. Grinding increased the reproducibility of sample mass reduction by rotary sectorial splitting by up to two orders of magnitude. Combined with rotary sectorial splitting, grinding increased the reproducibility of trace metal concentrations by almost three orders of magnitude compared to grab sampling. Moreover, results showed that if grinding is used as part of a mass reduction protocol by sectorial splitting, the effect of sieving on reproducibility became insignificant. Gy's sampling theory and practice was also used to analyze the aforementioned sampling protocols. While the theoretical relative variances calculated for each sampling protocol qualitatively agreed with the experimental variances, their quantitative agreement was very poor. It was assumed that the parameters used in the calculation of theoretical sampling variances may not correctly estimate the constitutional heterogeneity of soils or soil-like materials. Finally, the results have highlighted the pitfalls of grab sampling, namely, the fact that it does not exert control over incorrect sampling errors and that it is strongly affected by distribution heterogeneity.

Genetic demographic networks: Mathematical model and applications.

PubMed

Kimmel, Marek; Wojdyła, Tomasz

2016-10-01

Recent improvement in the quality of genetic data obtained from extinct human populations and their ancestors encourages searching for answers to basic questions regarding human population history. The most common and successful are model-based approaches, in which genetic data are compared to the data obtained from the assumed demography model. Using such approach, it is possible to either validate or adjust assumed demography. Model fit to data can be obtained based on reverse-time coalescent simulations or forward-time simulations. In this paper we introduce a computational method based on mathematical equation that allows obtaining joint distributions of pairs of individuals under a specified demography model, each of them characterized by a genetic variant at a chosen locus. The two individuals are randomly sampled from either the same or two different populations. The model assumes three types of demographic events (split, merge and migration). Populations evolve according to the time-continuous Moran model with drift and Markov-process mutation. This latter process is described by the Lyapunov-type equation introduced by O'Brien and generalized in our previous works. Application of this equation constitutes an original contribution. In the result section of the paper we present sample applications of our model to both simulated and literature-based demographies. Among other we include a study of the Slavs-Balts-Finns genetic relationship, in which we model split and migrations between the Balts and Slavs. We also include another example that involves the migration rates between farmers and hunters-gatherers, based on modern and ancient DNA samples. This latter process was previously studied using coalescent simulations. Our results are in general agreement with the previous method, which provides validation of our approach. Although our model is not an alternative to simulation methods in the practical sense, it provides an algorithm to compute pairwise distributions of alleles, in the case of haploid non-recombining loci such as mitochondrial and Y-chromosome loci in humans. Copyright © 2016 Elsevier Inc. All rights reserved.

A structural model of the dimensions of teacher stress.

PubMed

Boyle, G J; Borg, M G; Falzon, J M; Baglioni, A J

1995-03-01

A comprehensive survey of teacher stress, job satisfaction and career commitment among 710 full-time primary school teachers was undertaken by Borg, Riding & Falzon (1991) in the Mediterranean islands of Malta and Gozo. A principal components analysis of a 20-item sources of teacher stress inventory had suggested four distinct dimensions which were labelled: Pupil Misbehaviour, Time/Resource Difficulties, Professional Recognition Needs, and Poor Relationships, respectively. To check on the validity of the Borg et al. factor solution, the group of 710 teachers was randomly split into two separate samples. Exploratory factor analysis was carried out on the data from Sample 1 (N = 335), while Sample 2 (N = 375) provided the cross-validational data for a LISREL confirmatory factor analysis. Results supported the proposed dimensionality of the sources of teacher stress (measurement model), along with evidence of an additional teacher stress factor (Workload). Consequently, structural modelling of the 'causal relationships' between the various latent variables and self-reported stress was undertaken on the combined samples (N = 710). Although both non-recursive and recursive models incorporating Poor Colleague Relations as a mediating variable were tested for their goodness-of-fit, a simple regression model provided the most parsimonious fit to the empirical data, wherein Workload and Student Misbehaviour accounted for most of the variance in predicting teaching stress.

75 FR 38774 - Submission for OMB Review; Comment Request

Federal Register 2010, 2011, 2012, 2013, 2014

2010-07-06

... design research as part of testing for its censuses and surveys. At this time, the Census Bureau is... follows: Field test, Respondent debriefing questionnaire, Split sample experiments, Cognitive interviews... each round will be provided separately. When split sample experiments are conducted, either in small...

Integrating Genetic, Neuropsychological and Neuroimaging Data to Model Early-Onset Obsessive Compulsive Disorder Severity

PubMed Central

Mas, Sergi; Gassó, Patricia; Morer, Astrid; Calvo, Anna; Bargalló, Nuria; Lafuente, Amalia; Lázaro, Luisa

2016-01-01

We propose an integrative approach that combines structural magnetic resonance imaging data (MRI), diffusion tensor imaging data (DTI), neuropsychological data, and genetic data to predict early-onset obsessive compulsive disorder (OCD) severity. From a cohort of 87 patients, 56 with complete information were used in the present analysis. First, we performed a multivariate genetic association analysis of OCD severity with 266 genetic polymorphisms. This association analysis was used to select and prioritize the SNPs that would be included in the model. Second, we split the sample into a training set (N = 38) and a validation set (N = 18). Third, entropy-based measures of information gain were used for feature selection with the training subset. Fourth, the selected features were fed into two supervised methods of class prediction based on machine learning, using the leave-one-out procedure with the training set. Finally, the resulting model was validated with the validation set. Nine variables were used for the creation of the OCD severity predictor, including six genetic polymorphisms and three variables from the neuropsychological data. The developed model classified child and adolescent patients with OCD by disease severity with an accuracy of 0.90 in the testing set and 0.70 in the validation sample. Above its clinical applicability, the combination of particular neuropsychological, neuroimaging, and genetic characteristics could enhance our understanding of the neurobiological basis of the disorder. PMID:27093171

Assessing decentering: validation, psychometric properties, and clinical usefulness of the Experiences Questionnaire in a Spanish sample.

PubMed

Soler, Joaquim; Franquesa, Alba; Feliu-Soler, Albert; Cebolla, Ausias; García-Campayo, Javier; Tejedor, Rosa; Demarzo, Marcelo; Baños, Rosa; Pascual, Juan Carlos; Portella, Maria J

2014-11-01

Decentering is defined as the ability to observe one's thoughts and feelings in a detached manner. The Experiences Questionnaire (EQ) is a self-report instrument that originally assessed decentering and rumination. The purpose of this study was to evaluate the psychometric properties of the Spanish version of EQ-Decentering and to explore its clinical usefulness. The 11-item EQ-Decentering subscale was translated into Spanish and psychometric properties were examined in a sample of 921 adult individuals, 231 with psychiatric disorders and 690 without. The subsample of nonpsychiatric participants was also split according to their previous meditative experience (meditative participants, n=341; and nonmeditative participants, n=349). Additionally, differences among these three subgroups were explored to determine clinical validity of the scale. Finally, EQ-Decentering was administered twice in a group of borderline personality disorder, before and after a 10-week mindfulness intervention. Confirmatory factor analysis indicated acceptable model fit, sbχ(2)=243.8836 (p<.001), CFI=.939, GFI=.936, SRMR=.040, and RMSEA=.06 (.060-.077), and psychometric properties were found to be satisfactory (reliability: Cronbach's α=.893; convergent validity: r>.46; and divergent validity: r<-.35). The scale detected changes in decentering after a 10-session intervention in mindfulness (t=-4.692, p<.00001). Differences among groups were significant (F=134.8, p<.000001), where psychiatric participants showed the lowest scores compared to nonpsychiatric meditative and nonmeditative participants. The Spanish version of the EQ-Decentering is a valid and reliable instrument to assess decentering either in clinical and nonclinical samples. In addition, the findings show that EQ-Decentering seems an adequate outcome instrument to detect changes after mindfulness-based interventions. Copyright © 2014. Published by Elsevier Ltd.

Reliability and Factorial Structure of the Farsi Version of the Arabic Scale of Death Anxiety in an Iranian Middle-Aged Sample

PubMed Central

2016-01-01

The present study aimed to explore the psychometric properties of the Arabic Scale of Death Anxiety (ASDA) in an Iranian middle-aged sample. A sample of 55 volunteer Iranian persons took part in the study. Cronbach's alpha of the ASDA was found to be high (0.91) and Spearman-Brown and Guttman Split-Half coefficients were 0.86. The factor analysis of the ASDA items yielded five factors accounting for 72.49% of the total variance and labeled (F1) fear of death and fear of dead people; (F2) fear of postmortem events and fear of tombs; (F3) fear of lethal disease; (F4) preoccupation with after death, and death fear in sleep; and (F5) fear of deprivation of own ones. The ASDA has a good validity and reliability, and it can be used in clinical, educational, and research settings. PMID:28004035

Reliability and Factorial Structure of the Farsi Version of the Arabic Scale of Death Anxiety in an Iranian Middle-Aged Sample.

PubMed

Dadfar, Mahboubeh; Bahrami, Fazel

2016-01-01

The present study aimed to explore the psychometric properties of the Arabic Scale of Death Anxiety (ASDA) in an Iranian middle-aged sample. A sample of 55 volunteer Iranian persons took part in the study. Cronbach's alpha of the ASDA was found to be high (0.91) and Spearman-Brown and Guttman Split-Half coefficients were 0.86. The factor analysis of the ASDA items yielded five factors accounting for 72.49% of the total variance and labeled (F1) fear of death and fear of dead people; (F2) fear of postmortem events and fear of tombs; (F3) fear of lethal disease; (F4) preoccupation with after death, and death fear in sleep; and (F5) fear of deprivation of own ones. The ASDA has a good validity and reliability, and it can be used in clinical, educational, and research settings.

The Effect of Sequential Dependence on the Sampling Distributions of KR-20, KR-21, and Split-Halves Reliabilities.

ERIC Educational Resources Information Center

Sullins, Walter L.

Five-hundred dichotomously scored response patterns were generated with sequentially independent (SI) items and 500 with dependent (SD) items for each of thirty-six combinations of sampling parameters (i.e., three test lengths, three sample sizes, and four item difficulty distributions). KR-20, KR-21, and Split-Half (S-H) reliabilities were…

INNOVATIVE TECHNOLOGY EVALUATION REPORT, SEDIMENT SAMPLING TECHNOLOGY, ART'S MANUFACTURING, SPLIT CORE SAMPLER FOR SUBMERGED SEDIMENTS

EPA Science Inventory

The Split Core Sampler for Submerged Sediments (Split Core Sampler) designed and fabricated by Arts Manufacturing & Supply, Inc., was demonstrated under the U.S. Environmental Protection Agency (EPA) Superfund Innovative Technology Evaluation Program in April and May 1999 at ...

Reliability and Validity of the Chinese Version of FACIT-AI, a New Tool for Assessing Quality of Life in Patients with Malignant Ascites.

PubMed

Lou, Yanni; Lu, Linghui; Li, Yuan; Liu, Meng; Bredle, Jason M; Jia, Liqun

2015-10-01

The study objective was to determine the reliability and validity of the Chinese version of the Functional Assessment of Chronic Illness Therapy - Ascites Index (FACIT-AI). A forward-backward translation procedure was adopted to develop the Chinese version of the FACIT-AI, which was tested in 69 patients with malignant ascites. Cronbach's α, split-half reliability, and test-retest reliability were used to assess the reliability of the scale. The content validity index was used to assess the content validity, while factor analysis was used for construct validity and correlation analysis was used for criterion validity. The Cronbach's α was 0.772 for the total scale, and the split-half reliability was 0.693. The test-retest correlation was 0.972. The content validity index for the scale was 0.8-1.0. Four factors were extracted by factor analysis, and these contributed 63.51% of the total variance. Item-total correlations ranged from 0.591 to 0.897, and these were correlated with visual analog scale scores (correlation coefficient, 0.889; P<0.01). The Chinese version of the FACIT-AI has good reliability and validity and can be used as a tool to measure quality of life in Chinese patients with malignant ascites.

The negative consequences of other students' drinking: inventory development and assessment of differences by student characteristics and risk behaviors.

PubMed

Rhodes, Scott D; McCoy, Thomas P; Omli, Morrow R; Cohen, Gail M; Wagoner, Kimberly G; Durant, Robert H; Vissman, Aaron T; Wolfson, Mark

2009-01-01

College students continue to report being disrupted by other students' alcohol use. This study was designed to develop measures to document the consequences resulting from other students' drinking and identify differences in experiencing these consequences by student characteristics and drinking behaviors. A stratified random sample of undergraduate students (N = 3,908) from ten universities in North Carolina, USA, completed a web-based assessment. Exploratory factor analysis (EFA) was performed on the random first split-half sample (n = 1,954) to identify factor structure. Confirmatory factor analysis (CFA) was performed on the remaining half sample (n = 1,954) using structural equation modeling. EFA revealed two inventories: interpersonal and community consequences of others' drinking inventories. CFA on the second split-half sample identified model fits for the two factor structure suggested by EFA. Of 3,908 participants, 78% reported experiencing one or more consequences due to others' drinking during the past 30 days. Multivariable generalized linear mixed modeling further validated the inventories and resulted in several associations. Male students who reported getting drunk experienced significantly more interpersonal consequences from others' drinking (p < .001). Minority students, students who lived on campus and students who reported getting drunk experienced significantly more community consequences from others' drinking (p < .01). These findings demonstrate that 4 out of 5 college students experience consequences from others' drinking, and consequences vary for different subgroups of students. Although these inventories should be tested further, these findings propose standardized measures that may be useful to assess the consequences of others' drinking among college students.

Application of kinetic flux vector splitting scheme for solving multi-dimensional hydrodynamical models of semiconductor devices

NASA Astrophysics Data System (ADS)

Nisar, Ubaid Ahmed; Ashraf, Waqas; Qamar, Shamsul

In this article, one and two-dimensional hydrodynamical models of semiconductor devices are numerically investigated. The models treat the propagation of electrons in a semiconductor device as the flow of a charged compressible fluid. It plays an important role in predicting the behavior of electron flow in semiconductor devices. Mathematically, the governing equations form a convection-diffusion type system with a right hand side describing the relaxation effects and interaction with a self consistent electric field. The proposed numerical scheme is a splitting scheme based on the kinetic flux-vector splitting (KFVS) method for the hyperbolic step, and a semi-implicit Runge-Kutta method for the relaxation step. The KFVS method is based on the direct splitting of macroscopic flux functions of the system on the cell interfaces. The second order accuracy of the scheme is achieved by using MUSCL-type initial reconstruction and Runge-Kutta time stepping method. Several case studies are considered. For validation, the results of current scheme are compared with those obtained from the splitting scheme based on the NT central scheme. The effects of various parameters such as low field mobility, device length, lattice temperature and voltage are analyzed. The accuracy, efficiency and simplicity of the proposed KFVS scheme validates its generic applicability to the given model equations. A two dimensional simulation is also performed by KFVS method for a MESFET device, producing results in good agreement with those obtained by NT-central scheme.

A systematic review finds methodological improvements necessary for prognostic models in determining traumatic brain injury outcomes.

PubMed

Mushkudiani, Nino A; Hukkelhoven, Chantal W P M; Hernández, Adrián V; Murray, Gordon D; Choi, Sung C; Maas, Andrew I R; Steyerberg, Ewout W

2008-04-01

To describe the modeling techniques used for early prediction of outcome in traumatic brain injury (TBI) and to identify aspects for potential improvements. We reviewed key methodological aspects of studies published between 1970 and 2005 that proposed a prognostic model for the Glasgow Outcome Scale of TBI based on admission data. We included 31 papers. Twenty-four were single-center studies, and 22 reported on fewer than 500 patients. The median of the number of initially considered predictors was eight, and on average five of these were selected for the prognostic model, generally including age, Glasgow Coma Score (or only motor score), and pupillary reactivity. The most common statistical technique was logistic regression with stepwise selection of predictors. Model performance was often quantified by accuracy rate rather than by more appropriate measures such as the area under the receiver-operating characteristic curve. Model validity was addressed in 15 studies, but mostly used a simple split-sample approach, and external validation was performed in only four studies. Although most models agree on the three most important predictors, many were developed on small sample sizes within single centers and hence lack generalizability. Modeling strategies have to be improved, and include external validation.

Hinge Moment Coefficient Prediction Tool and Control Force Analysis of Extra-300 Aerobatic Aircraft

NASA Astrophysics Data System (ADS)

Nurohman, Chandra; Arifianto, Ony; Barecasco, Agra

2018-04-01

This paper presents the development of tool that is applicable to predict hinge moment coefficients of subsonic aircraft based on Roskam’s method, including the validation and its application to predict hinge moment coefficient of an Extra-300. The hinge moment coefficients are used to predict the stick forces of the aircraft during several aerobatic maneuver i.e. inside loop, half cuban 8, split-s, and aileron roll. The maximum longitudinal stick force is 566.97 N occurs in inside loop while the maximum lateral stick force is 340.82 N occurs in aileron roll. Furthermore, validation hinge moment prediction method is performed using Cessna 172 data.

Sample selection via angular distance in the space of the arguments of an artificial neural network

NASA Astrophysics Data System (ADS)

Fernández Jaramillo, J. M.; Mayerle, R.

2018-05-01

In the construction of an artificial neural network (ANN) a proper data splitting of the available samples plays a major role in the training process. This selection of subsets for training, testing and validation affects the generalization ability of the neural network. Also the number of samples has an impact in the time required for the design of the ANN and the training. This paper introduces an efficient and simple method for reducing the set of samples used for training a neural network. The method reduces the required time to calculate the network coefficients, while keeping the diversity and avoiding overtraining the ANN due the presence of similar samples. The proposed method is based on the calculation of the angle between two vectors, each one representing one input of the neural network. When the angle formed among samples is smaller than a defined threshold only one input is accepted for the training. The accepted inputs are scattered throughout the sample space. Tidal records are used to demonstrate the proposed method. The results of a cross-validation show that with few inputs the quality of the outputs is not accurate and depends on the selection of the first sample, but as the number of inputs increases the accuracy is improved and differences among the scenarios with a different starting sample have and important reduction. A comparison with the K-means clustering algorithm shows that for this application the proposed method with a smaller number of samples is producing a more accurate network.

Tracing Surrogates for Enteric Pathogens Inoculated on Hide through the Beef Harvesting Process.

PubMed

Villarreal-Silva, Mariana; Genho, Daniel P; Ilhak, Irfan; Lucia, Lisa M; Dickson, James S; Gehring, Kerri B; Savell, Jeffrey W; Castillo, Alejandro

2016-11-01

Multiple antimicrobial interventions have been validated for use during the beef postharvesting process. However, little has been done to determine the impact of the postharvest environment on pathogen contamination. In this study, surrogate microorganisms were used to simulate pathogen cross-contamination through the postharvest environment at three different abattoirs. At each abattoir, the brisket areas of 13 hide-on carcasses were inoculated after stunning, with a gelatin slurry containing a cocktail (~7 log CFU/ml) of fluorescent Escherichia coli biotype I. These microorganisms are approved as surrogates for E. coli O157:H7 and Salmonella . From these carcasses, samples (300 cm 2 ) were taken at different stages during the harvesting process: after hide opening, prior to evisceration, after evisceration, after splitting, and after final intervention. The carcass (noninoculated) immediately following (adjacent to) each hide-inoculated carcass was also tested to determine cross-contamination. Environmental (floor, walls, air) and personal garment (gloves, boots, aprons) samples were collected. Other sampled equipment included knives, meat hooks, hide pullers, and splitting saws. Results demonstrated that cross-contamination occurred between the inoculated hide and the carcass and also by transfer of microorganisms to the adjacent, noninoculated carcasses. Microbial transfer also occurred from hides or carcasses to the environment, personal garments, and equipment. Counts of the surrogate bacteria used were higher in equipment samples (15%) than in environment samples (10%). Personal garments had the lowest occurrence of cross-contamination (7%). For all abattoirs, surrogates were undetected on the carcass (<1.4 log CFU/300cm 2 ) after the final intervention stage. This study confirms the importance of following adequate procedures for carcass dressing and highlights an adequate hide opening procedure as a crucial step to prevent carcass contamination.

Validation of French and German versions of a Perceived Neighborhood Social Cohesion Questionnaire among young Swiss males, and its relationship with substance use.

PubMed

Dupuis, Marc; Studer, Joseph; Henchoz, Yves; Deline, Stéphane; Baggio, Stéphanie; N'Goran, Alexandra; Mohler-Kuo, Meichun; Gmel, Gerhard

2016-02-01

This study main purpose was the validation of both French and German versions of a Perceived Neighborhood Social Cohesion Questionnaire. The sample group comprised 5065 Swiss men from the "Cohort Study on Substance Use Risk Factors." Multigroup Confirmatory factor analysis showed that a three-factor model fits the data well, which substantiates the generalizability of Perceived Neighborhood Social Cohesion Questionnaire factor structure, regardless of the language. The Perceived Neighborhood Social Cohesion Questionnaire demonstrated excellent homogeneity (α = 95) and split-half reliability (r = .96). The Perceived Neighborhood Social Cohesion Questionnaire was sensitive to community size and participants' financial situation, confirming that it also measures real social conditions. Finally, weak but frequent correlations between Perceived Neighborhood Social Cohesion Questionnaire and alcohol, cigarette, and cannabis dependence were measured. © The Author(s) 2014.

Finite strain transient creep of D16T alloy: identification and validation employing heterogeneous tests

NASA Astrophysics Data System (ADS)

Shutov, A. V.; Larichkin, A. Yu

2017-10-01

A cyclic creep damage model, previously proposed by the authors, is modified for a better description of the transient creep of D16T alloy observed in the finite strain range under rapidly changing stresses. The new model encompasses the concept of kinematic hardening, which allows us to account for the creep-induced anisotropy. The model kinematics is based on the nested multiplicative split of the deformation gradient, proposed by Lion. The damage evolution is accounted for by the classical Kachanov-Rabotnov approach. The material parameters are identified using experimental data on cyclic torsion of thick-walled samples with different holding times between load reversals. For the validation of the proposed material model, an additional experiment is analyzed. Although this additional test is not involved in the identification procedure, the proposed cyclic creep damage model describes it accurately.

The development of the "Cantonese receptive vocabulary test' for children aged 2-6 in Hong Kong.

PubMed

Cheung, P S; Lee, K Y; Lee, L W

1997-01-01

The study aims to develop a Cantonese receptive vocabulary test to assess 2-6-year-old children in Hong Kong. The test consists of 100 test items. Each target item is accompanied by a phonological distractor, a semantic distractor and an unrelated distractor. A sample of 609 normal children from four Maternal and Child Health Centres and nine kindergartens was selected. The results show that there is a significant effect of age on the correct score. ANOVA was performed to look at the age effect on each distractor individually. It was found that the scores of the three distractors decrease in their own patterns as age increases. With strong content validity, strong construct validity and high correlation coefficients in the split-half reliability, this test could be used as a reliable measurement for the Cantonese-speaking population in Hong Kong.

Classification of dry-cured hams according to the maturation time using near infrared spectra and artificial neural networks.

PubMed

Prevolnik, M; Andronikov, D; Žlender, B; Font-i-Furnols, M; Novič, M; Škorjanc, D; Čandek-Potokar, M

2014-01-01

An attempt to classify dry-cured hams according to the maturation time on the basis of near infrared (NIR) spectra was studied. The study comprised 128 samples of biceps femoris (BF) muscle from dry-cured hams matured for 10 (n=32), 12 (n=32), 14 (n=32) or 16 months (n=32). Samples were minced and scanned in the wavelength range from 400 to 2500 nm using spectrometer NIR System model 6500 (Silver Spring, MD, USA). Spectral data were used for i) splitting of samples into the training and test set using 2D Kohonen artificial neural networks (ANN) and for ii) construction of classification models using counter-propagation ANN (CP-ANN). Different models were tested, and the one selected was based on the lowest percentage of misclassified test samples (external validation). Overall correctness of the classification was 79.7%, which demonstrates practical relevance of using NIR spectroscopy and ANN for dry-cured ham processing control. Copyright © 2013 Elsevier Ltd. All rights reserved.

Split rheometer Couette attachment to enable sample extraction

NASA Astrophysics Data System (ADS)

Guthrie, Sarah E.; Idziak, Stefan H. J.

2005-02-01

We report on the development of a Couette attachment insert for a rheometer, which is designed to split in half, enabling intact sample extraction of cocoa butter crystallized from the melt under known dynamic stress conditions. This cell is capable of producing a sample 1mm thick. At shear rates of 90-720s-1 and final temperatures of 18-20°C it was shown that the sample will completely separate from the cell surface intact.

Modeling vehicle operating speed on urban roads in Montreal: a panel mixed ordered probit fractional split model.

PubMed

Eluru, Naveen; Chakour, Vincent; Chamberlain, Morgan; Miranda-Moreno, Luis F

2013-10-01

Vehicle operating speed measured on roadways is a critical component for a host of analysis in the transportation field including transportation safety, traffic flow modeling, roadway geometric design, vehicle emissions modeling, and road user route decisions. The current research effort contributes to the literature on examining vehicle speed on urban roads methodologically and substantively. In terms of methodology, we formulate a new econometric model framework for examining speed profiles. The proposed model is an ordered response formulation of a fractional split model. The ordered nature of the speed variable allows us to propose an ordered variant of the fractional split model in the literature. The proposed formulation allows us to model the proportion of vehicles traveling in each speed interval for the entire segment of roadway. We extend the model to allow the influence of exogenous variables to vary across the population. Further, we develop a panel mixed version of the fractional split model to account for the influence of site-specific unobserved effects. The paper contributes substantively by estimating the proposed model using a unique dataset from Montreal consisting of weekly speed data (collected in hourly intervals) for about 50 local roads and 70 arterial roads. We estimate separate models for local roads and arterial roads. The model estimation exercise considers a whole host of variables including geometric design attributes, roadway attributes, traffic characteristics and environmental factors. The model results highlight the role of various street characteristics including number of lanes, presence of parking, presence of sidewalks, vertical grade, and bicycle route on vehicle speed proportions. The results also highlight the presence of site-specific unobserved effects influencing the speed distribution. The parameters from the modeling exercise are validated using a hold-out sample not considered for model estimation. The results indicate that the proposed panel mixed ordered probit fractional split model offers promise for modeling such proportional ordinal variables. Copyright © 2013 Elsevier Ltd. All rights reserved.

Bayesian inferences suggest that Amazon Yunga Natives diverged from Andeans less than 5000 ybp: implications for South American prehistory.

PubMed

Scliar, Marilia O; Gouveia, Mateus H; Benazzo, Andrea; Ghirotto, Silvia; Fagundes, Nelson J R; Leal, Thiago P; Magalhães, Wagner C S; Pereira, Latife; Rodrigues, Maira R; Soares-Souza, Giordano B; Cabrera, Lilia; Berg, Douglas E; Gilman, Robert H; Bertorelle, Giorgio; Tarazona-Santos, Eduardo

2014-09-30

Archaeology reports millenary cultural contacts between Peruvian Coast-Andes and the Amazon Yunga, a rainforest transitional region between Andes and Lower Amazonia. To clarify the relationships between cultural and biological evolution of these populations, in particular between Amazon Yungas and Andeans, we used DNA-sequence data, a model-based Bayesian approach and several statistical validations to infer a set of demographic parameters. We found that the genetic diversity of the Shimaa (an Amazon Yunga population) is a subset of that of Quechuas from Central-Andes. Using the Isolation-with-Migration population genetics model, we inferred that the Shimaa ancestors were a small subgroup that split less than 5300 years ago (after the development of complex societies) from an ancestral Andean population. After the split, the most plausible scenario compatible with our results is that the ancestors of Shimaas moved toward the Peruvian Amazon Yunga and incorporated the culture and language of some of their neighbors, but not a substantial amount of their genes. We validated our results using Approximate Bayesian Computations, posterior predictive tests and the analysis of pseudo-observed datasets. We presented a case study in which model-based Bayesian approaches, combined with necessary statistical validations, shed light into the prehistoric demographic relationship between Andeans and a population from the Amazon Yunga. Our results offer a testable model for the peopling of this large transitional environmental region between the Andes and the Lower Amazonia. However, studies on larger samples and involving more populations of these regions are necessary to confirm if the predominant Andean biological origin of the Shimaas is the rule, and not the exception.

Using Divertor Strike Point Splitting to Study Plasma Response and Its Sensitivity to Equilibrium Uncertainties

NASA Astrophysics Data System (ADS)

Teklu, Abraham; Orlov, D. M.; Moyer, R. A.; Bykov, I.; Evans, T. E.; Wu, W.; Trevisan, G. L.; Lyons, B. C.; Abrams, T.; Makowski, M. A.; Lasnier, C. S.; Fenstermacher, M. E.

2017-10-01

Resonant magnetic perturbations (RMPs) from 3D coils have been varied to modify the splitting of the divertor strike points in DIII-D. This splitting is imaged in filtered visible and infrared emission from the divertor to determine the particle and heat flux patterns on the target plates. The observed splitting is compared to vacuum and plasma response modeling in discharges where a subset of the RMP coils were ramped to shift the divertor footprints from dominantly n = 3 to n = 2 pattern. These results will be used to determine if the plasma response model can be validated with the measured splitting. We will also study the sensitivity of the modeled splitting to details of the 2D equilibrium. This RMP ramp technique could be used in ITER to spread out the heat flux while avoiding excessive forces on the RMP coils. Work supported by U.S. DOE under the Science Undergraduate Laboratory Internship (SULI) program and DE-FC02-04ER54698, DE-FG02-07ER54917, DE-FG02-05ER54809 and DE-AC52-07NA27344.

An Investigation of Sample Size Splitting on ATFIND and DIMTEST

ERIC Educational Resources Information Center

Socha, Alan; DeMars, Christine E.

2013-01-01

Modeling multidimensional test data with a unidimensional model can result in serious statistical errors, such as bias in item parameter estimates. Many methods exist for assessing the dimensionality of a test. The current study focused on DIMTEST. Using simulated data, the effects of sample size splitting for use with the ATFIND procedure for…

Reinforcement Learning Trees

PubMed Central

Zhu, Ruoqing; Zeng, Donglin; Kosorok, Michael R.

2015-01-01

In this paper, we introduce a new type of tree-based method, reinforcement learning trees (RLT), which exhibits significantly improved performance over traditional methods such as random forests (Breiman, 2001) under high-dimensional settings. The innovations are three-fold. First, the new method implements reinforcement learning at each selection of a splitting variable during the tree construction processes. By splitting on the variable that brings the greatest future improvement in later splits, rather than choosing the one with largest marginal effect from the immediate split, the constructed tree utilizes the available samples in a more efficient way. Moreover, such an approach enables linear combination cuts at little extra computational cost. Second, we propose a variable muting procedure that progressively eliminates noise variables during the construction of each individual tree. The muting procedure also takes advantage of reinforcement learning and prevents noise variables from being considered in the search for splitting rules, so that towards terminal nodes, where the sample size is small, the splitting rules are still constructed from only strong variables. Last, we investigate asymptotic properties of the proposed method under basic assumptions and discuss rationale in general settings. PMID:26903687

Validation of the German revised version of the program in palliative care education and practice questionnaire (PCEP-GR).

PubMed

Fetz, Katharina; Wenzel-Meyburg, Ursula; Schulz-Quach, Christian

2017-12-28

The evaluation of the effectiveness of undergraduate palliative care education (UPCE) programs is an essential foundation to providing high-quality UPCE programs. Therefore, the implementation of valid evaluation tools is indispensable. Until today, there has been no general consensus regarding concrete outcome parameters and their accurate measurement. The Program in Palliative Care Education and Practice Questionnaire (German Revised Version; PCEP-GR) is a promising assessment tool for UPCE. The aim of the current study was to evaluate the psychometric properties of PCEP-GR and to demonstrate its feasibility for the evaluation of UPCE programs. The practical feasibility of the PCEP-GR and its acceptance in medical students were investigated in a pilot study with 24 undergraduate medical students at Heinrich Heine University Dusseldorf, Germany. Subsequently, the PCEP-GR was surveyed in a representative sample (N = 680) of medical students in order to investigate its psychometric properties. Factorial validity was investigated by means of principal component analysis (PCA). Reliability was examined by means of split-half-reliability analysis and analysis of internal consistency. After taking into consideration the PCA and distribution analysis results, an evaluation instruction for the PCEP-GR was developed. The PCEP-GR proved to be feasible and well-accepted in medical students. PCA revealed a four-factorial solution indicating four PCEP-GR subscales: preparation to provide palliative care, attitudes towards palliative care, self-estimation of competence in communication with dying patients and their relatives and self-estimation of knowledge and skills in palliative care. The PCEP-GR showed good split-half-reliability and acceptable to good internal consistency of subscales. Attitudes towards palliative care slightly missed the criterion of acceptable internal consistency. The evaluation instruction suggests a global PCEP-GR index and four subscales. The PCEP-GR has proven to be a feasible, economic, valid and reliable tool for the assessment of UPCE that comprises self-efficacy expectation and relevant attitudes towards palliative care.

Characterization and modeling of the stress and pore-fluid dependent acoustic properties of fractured porous rocks

NASA Astrophysics Data System (ADS)

Almrabat, Abdulhadi M.

The thesis presents the results of a study of the characterization and modeling of the stress and pore-fluid dependent acoustic properties of fractured porous rocks. A new laboratory High Pressure and High Temperature (HPHT) triaxial testing system was developed to characterize the seismic properties of sandstone under different levels of effective stress confinement and changes in pore-fluid composition. An intact and fractured of Berea sandstones core samples were used in the experimental studies. The laboratory test results were used to develop analytical models for stress-level and pore-fluid dependent seismic velocity of sandstones. Models for stress-dependent P and S-wave seismic velocities of sandstone were then developed based on the assumption that stress-dependencies come from the nonlinear elastic response of micro-fractures contained in the sample under normal and shear loading. The contact shear stiffness was assumed to increase linearly with the normal stress across a micro-fracture, while the contact normal stiffness was assumed to vary as a power law with the micro-fracture normal stress. Both nonlinear fracture normal and shear contact models were validated by experimental data available in the literature. To test the dependency of seismic velocity of sandstone on changes in pore-fluid composition, another series of tests were conducted where P and S-wave velocities were monitored during injection of supercritical CO 2 in samples of Berea sandstone initially saturated with saline water and under constant confining stress. Changes in seismic wave velocity were measured at different levels of supercritical CO2 saturation as the initial saline water as pore-fluid was displaced by supercritical CO 2. It was found that the P- iv wave velocity significantly decreased while the S-wave velocity remained almost constant as the sample supercritical CO2 saturation increased. The dependency of the seismic velocity on changes on pore fluid composition during injection of supercritical CO 2 in Berea sandstone was modeled using a re-derived Biot-Gassmann substitution theory. In using the Biot-Gassmann substitution theory, it was found necessary to account for the changes in the pore-fluid compressibility in terms of the volumetric proportion and distribution of saline water and supercritical CO 2 in the sample pore space. This was done by using the empirical model of Brie et al. to account for the compressibility of mixtures of two-phase immiscible fluids. The combined Biot-Gassman and Brie et al. models were found to represent adequately the changes in P-wave velocity of Berea sandstone during displacement of saline water by supercritical CO2. The third experimental and modeling study addressed shear-wave splitting due to the presence of fractures in a rock mass. Tests were conducted using the high temperature and high pressure (HPHT) triaxial device on samples of Berea sandstone, containing a single induced tensile fracture running along the height of the sample. The fracture was created via a modified Brazilian Split Test loading where the edges of cylindrical samples were loaded on diametrically opposite two points by sharp guillotines. The Joint Roughness Coefficient (JRC) values of the fractured core samples were determined by profilometry and tilt test. The effect of mismatching of the fracture surfaces on shear wave splitting was investigated by applying different amounts of shear displacements to three core samples. The degree of mismatching of the fracture surfaces in the core samples was evaluated using the Joint Matching Coefficient (JMC). Shear-wave splitting, as measured by the difference in magnitudes of shear-wave velocities parallel and perpendicular to the fracture, Vs1 and Vs2 respectively, increases with increasing mismatch of the fracture surfaces and decreases with increasing effective stress, and approaches zero in the effective stress range tested. A model for the stress and JMC dependent shear-wave splitting was developed based on the experimental observations. Finally, the magnitude of shear-wave splitting was correlated with the permeability of the fractured porous sandstone for fluid flow parallel to the induced fracture. (Abstract shortened by UMI.)

Zeeman splitting of 6.7 GHz methanol masers. On the uncertainty of magnetic field strength determinations

NASA Astrophysics Data System (ADS)

Vlemmings, W. H. T.; Torres, R. M.; Dodson, R.

2011-05-01

Context. To properly determine the role of magnetic fields during massive star formation, a statistically significant sample of field measurements probing different densities and regions around massive protostars needs to be established. However, relating Zeeman splitting measurements to magnetic field strengths needs a carefully determined splitting coefficient. Aims: Polarization observations of, in particular, the very abundant 6.7 GHz methanol maser, indicate that these masers appear to be good probes of the large scale magnetic field around massive protostars at number densities up to nH2 ≈ 109 cm-3. We thus investigate the Zeeman splitting of the 6.7 GHz methanol maser transition. Methods: We have observed of a sample of 46 bright northern hemisphere maser sources with the Effelsberg 100-m telescope and an additional 34 bright southern masers with the Parkes 64-m telescope in an attempt to measure their Zeeman splitting. We also revisit the previous calculation of the methanol Zeeman splitting coefficients and show that these were severely overestimated making the determination of magnetic field strengths highly uncertain. Results: In total 44 of the northern masers were detected and significant splitting between the right- and left-circular polarization spectra is determined in >75% of the sources with a flux density >20 Jy beam-1. Assuming the splitting is due to a magnetic field according to the regular Zeeman effect, the average detected Zeeman splitting corrected for field geometry is ~0.6 m s-1. Using an estimate of the 6.7 GHz A-type methanol maser Zeeman splitting coefficient based on old laboratory measurements of 25 GHz E-type methanol transitions this corresponds to a magnetic field of ~120 mG in the methanol maser region. This is significantly higher than expected using the typically assumed relation between magnetic field and density (B∝ n_H_20.47) and potentially indicates the extrapolation of the available laboratory measurements is invalid. The stability of the right- and left-circular calibration of the Parkes observations was insufficient to determine the Zeeman splitting of the Southern sample. Spectra are presented for all sources in both samples. Conclusions: There is no strong indication that the measured splitting between right- and left-circular polarization is due to non-Zeeman effects, although this cannot be ruled out until the Zeeman coefficient is properly determined. However, although the 6.7 GHz methanol masers are still excellent magnetic field morphology probes through linear polarization observations, previous derivations of magnetic fields strength turn out to be highly uncertain. A solution to this problem will require new laboratory measurements of the methanol Landé-factors. Table 2 and Figs. 5-7 are only available in electronic form at http://www.aanda.org

Analytical Method to Estimate the Complex Permittivity of Oil Samples.

PubMed

Su, Lijuan; Mata-Contreras, Javier; Vélez, Paris; Fernández-Prieto, Armando; Martín, Ferran

2018-03-26

In this paper, an analytical method to estimate the complex dielectric constant of liquids is presented. The method is based on the measurement of the transmission coefficient in an embedded microstrip line loaded with a complementary split ring resonator (CSRR), which is etched in the ground plane. From this response, the dielectric constant and loss tangent of the liquid under test (LUT) can be extracted, provided that the CSRR is surrounded by such LUT, and the liquid level extends beyond the region where the electromagnetic fields generated by the CSRR are present. For that purpose, a liquid container acting as a pool is added to the structure. The main advantage of this method, which is validated from the measurement of the complex dielectric constant of olive and castor oil, is that reference samples for calibration are not required.

Development and validation of a tool to assess knowledge and attitudes towards generic medicines among students in Greece: The ATtitude TOwards GENerics (ATTOGEN) questionnaire.

PubMed

Domeyer, Philip J; Aletras, Vassilis; Anagnostopoulos, Fotios; Katsari, Vasiliki; Niakas, Dimitris

2017-01-01

The use of generic medicines is a cost-effective policy, often dictated by fiscal restraints. To our knowledge, no fully validated tool exploring the students' knowledge and attitudes towards generic medicines exists. The aim of our study was to develop and validate a questionnaire exploring the knowledge and attitudes of M.Sc. in Health Care Management students and recent alumni's towards generic drugs in Greece. The development of the questionnaire was a result of literature review and pilot-testing of its preliminary versions to researchers and students. The final version of the questionnaire contains 18 items measuring the respondents' knowledge and attitude towards generic medicines on a 5-point Likert scale. Given the ordinal nature of the data, ordinal alpha and polychoric correlations were computed. The sample was randomly split into two halves. Exploratory factor analysis, performed in the first sample, was used for the creation of multi-item scales. Confirmatory factor analysis and Generalized Linear Latent and Mixed Model analysis (GLLAMM) with the use of the rating scale model were used in the second sample to assess goodness of fit. An assessment of internal consistency reliability, test-retest reliability, and construct validity was also performed. Among 1402 persons contacted, 986 persons completed our questionnaire (response rate = 70.3%). Overall Cronbach's alpha was 0.871. The conjoint use of exploratory and confirmatory factor analysis resulted in a six-scale model, which seemed to fit the data well. Five of the six scales, namely trust, drug quality, state audit, fiscal impact and drug substitution were found to be valid and reliable, while the knowledge scale suffered only from low inter-scale correlations and a ceiling effect. However, the subsequent confirmatory factor and GLLAMM analyses indicated a good fit of the model to the data. The ATTOGEN instrument proved to be a reliable and valid tool, suitable for assessing students' knowledge and attitudes towards generic medicines.

Reliability and validity of the revised Gibson Test of Cognitive Skills, a computer-based test battery for assessing cognition across the lifespan.

PubMed

Moore, Amy Lawson; Miller, Terissa M

2018-01-01

The purpose of the current study is to evaluate the validity and reliability of the revised Gibson Test of Cognitive Skills, a computer-based battery of tests measuring short-term memory, long-term memory, processing speed, logic and reasoning, visual processing, as well as auditory processing and word attack skills. This study included 2,737 participants aged 5-85 years. A series of studies was conducted to examine the validity and reliability using the test performance of the entire norming group and several subgroups. The evaluation of the technical properties of the test battery included content validation by subject matter experts, item analysis and coefficient alpha, test-retest reliability, split-half reliability, and analysis of concurrent validity with the Woodcock Johnson III Tests of Cognitive Abilities and Tests of Achievement. Results indicated strong sources of evidence of validity and reliability for the test, including internal consistency reliability coefficients ranging from 0.87 to 0.98, test-retest reliability coefficients ranging from 0.69 to 0.91, split-half reliability coefficients ranging from 0.87 to 0.91, and concurrent validity coefficients ranging from 0.53 to 0.93. The Gibson Test of Cognitive Skills-2 is a reliable and valid tool for assessing cognition in the general population across the lifespan.

Informational and decisional empowerment in online health support communities: initial psychometric validation of the Cyber Info-Decisional Empowerment Scale (CIDES) and preliminary data from administration of the scale.

PubMed

Seçkin, Gül

2011-12-01

This article presents initial psychometric validation of an instrument developed to measure cyber informational and decisional empowerment. The article provides preliminary insights into the extent to which cyber patients view the digital environment of peer-based information and support as a resource for informed and empowered participation in self health care management. Data come from cancer patients (N = 350) who participated in the Study of Virtual Health Networks for Cancer Patients of the 21st Century. Data were first analyzed using exploratory factor analysis with principle component extraction and Varimax rotation. Age-based split-sample analysis (≥ 51 and ≤ 50) was performed on a subsample, which consisted of only women (N = 255), in order to cross-validate psychometric data obtained from the full sample. A confirmatory factor analysis was conducted using AMOS 19.0. to further validate the scale. The composite scale is unidimensional with excellent internal consistency reliability. The highest average scores were obtained for informational empowerment items. The lowest average was for the item that measured empowerment to seek second opinion from additional health care professionals. The ability of this composite measure to provide information about the extent to which computer-connected patients view digital peer support as an empowerment tool makes it a valuable addition to the literature in health informatics, supportive cancer care, and health quality of life research.

Interest in Aesthetic Rhinoplasty Scale.

PubMed

Naraghi, Mohsen; Atari, Mohammad

2017-04-01

Interest in cosmetic surgery is increasing, with rhinoplasty being one of the most popular surgical procedures. It is essential that surgeons identify patients with existing psychological conditions before any procedure. This study aimed to develop and validate the Interest in Aesthetic Rhinoplasty Scale (IARS). Four studies were conducted to develop the IARS and to evaluate different indices of validity (face, content, construct, criterion, and concurrent validities) and reliability (internal consistency, split-half coefficient, and temporal stability) of the scale. The four study samples included a total of 463 participants. Statistical analysis revealed satisfactory psychometric properties in all samples. Scores on the IARS were negatively correlated with self-esteem scores ( r  = -0.296; p  < 0.01) and positively associated with scores for psychopathologic symptoms ( r  = 0.164; p  < 0.05), social dysfunction ( r  = 0.268; p  < 0.01), and depression ( r  = 0.308; p  < 0.01). The internal and test-retest coefficients of consistency were found to be high (α = 0.93; intraclass coefficient = 0.94). Rhinoplasty patients were found to have significantly higher IARS scores than nonpatients ( p  < 0.001). Findings of the present studies provided evidence for face, content, construct, criterion, and concurrent validities and internal and test-retest reliability of the IARS. This evidence supports the use of the scale in clinical and research settings. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Are Model Transferability And Complexity Antithetical? Insights From Validation of a Variable-Complexity Empirical Snow Model in Space and Time

NASA Astrophysics Data System (ADS)

Lute, A. C.; Luce, Charles H.

2017-11-01

The related challenges of predictions in ungauged basins and predictions in ungauged climates point to the need to develop environmental models that are transferable across both space and time. Hydrologic modeling has historically focused on modelling one or only a few basins using highly parameterized conceptual or physically based models. However, model parameters and structures have been shown to change significantly when calibrated to new basins or time periods, suggesting that model complexity and model transferability may be antithetical. Empirical space-for-time models provide a framework within which to assess model transferability and any tradeoff with model complexity. Using 497 SNOTEL sites in the western U.S., we develop space-for-time models of April 1 SWE and Snow Residence Time based on mean winter temperature and cumulative winter precipitation. The transferability of the models to new conditions (in both space and time) is assessed using non-random cross-validation tests with consideration of the influence of model complexity on transferability. As others have noted, the algorithmic empirical models transfer best when minimal extrapolation in input variables is required. Temporal split-sample validations use pseudoreplicated samples, resulting in the selection of overly complex models, which has implications for the design of hydrologic model validation tests. Finally, we show that low to moderate complexity models transfer most successfully to new conditions in space and time, providing empirical confirmation of the parsimony principal.

Interim results of quality-control sampling of surface water for the Upper Colorado River National Water-Quality Assessment Study Unit, water years 1995-96

USGS Publications Warehouse

Spahr, N.E.; Boulger, R.W.

1997-01-01

Quality-control samples provide part of the information needed to estimate the bias and variability that result from sample collection, processing, and analysis. Quality-control samples of surface water collected for the Upper Colorado River National Water-Quality Assessment study unit for water years 1995?96 are presented and analyzed in this report. The types of quality-control samples collected include pre-processing split replicates, concurrent replicates, sequential replicates, post-processing split replicates, and field blanks. Analysis of the pre-processing split replicates, concurrent replicates, sequential replicates, and post-processing split replicates is based on differences between analytical results of the environmental samples and analytical results of the quality-control samples. Results of these comparisons indicate that variability introduced by sample collection, processing, and handling is low and will not affect interpretation of the environmental data. The differences for most water-quality constituents is on the order of plus or minus 1 or 2 lowest rounding units. A lowest rounding unit is equivalent to the magnitude of the least significant figure reported for analytical results. The use of lowest rounding units avoids some of the difficulty in comparing differences between pairs of samples when concentrations span orders of magnitude and provides a measure of the practical significance of the effect of variability. Analysis of field-blank quality-control samples indicates that with the exception of chloride and silica, no systematic contamination of samples is apparent. Chloride contamination probably was the result of incomplete rinsing of the dilute cleaning solution from the outlet ports of the decaport sample splitter. Silica contamination seems to have been introduced by the blank water. Sampling and processing procedures for water year 1997 have been modified as a result of these analyses.

Development of a split-flow system for high precision variable sample introduction in supercritical fluid chromatography.

PubMed

Sakai, Miho; Hayakawa, Yoshihiro; Funada, Yasuhiro; Ando, Takashi; Fukusaki, Eiichiro; Bamba, Takeshi

2017-09-15

In this study, we propose a novel variable sample injection system based on full-loop injection, named the split-flow sample introduction system, for application in supercritical fluid chromatography (SFC). In this system, the mobile phase is split by the differential pressure between two back pressure regulators (BPRs) after full-loop injection suitable for SFC, and this differential pressure determines the introduction rate. Nine compounds with a wide range of characteristics were introduced with high reproducibility and universality, confirming that a robust variable sample injection system was achieved. We also investigated the control factors of our proposed system. Sample introduction was controlled by the ratio between the column-side pressure drops in splitless and split flow, ΔP columnsideinsplitless and ΔP columnsideinsplit , respectively, where ΔP columnsideinsplitless is related to the mobile phase flow rate and composition and the column resistance. When all other conditions are kept constant, increasing the make-up flow induces an additional pressure drop on the column side of the system, which leads to a reduced column-side flow rate, and hence decreased the amount of sample injected, even when the net pressure drop on the column side remains the same. Thus, sample introduction could be highly controlled at low sample introduction rate, regardless of the introduction conditions. This feature is advantageous because, as a control factor, the solvent in the make-up pump is independent of the column-side pressure drop. Copyright © 2017. Published by Elsevier B.V.

In-hospital fall-risk screening in 4,735 geriatric patients from the LUCAS project.

PubMed

Neumann, L; Hoffmann, V S; Golgert, S; Hasford, J; Von Renteln-Kruse, W

2013-03-01

In-hospital falls in older patients are frequent, but the identification of patients at risk of falling is challenging. Aim of this study was to improve the identification of high-risk patients. Therefore, a simplified screening-tool was developed, validated, and compared to the STRATIFY predictive accuracy. Retrospective analysis of 4,735 patients; evaluation of predictive accuracy of STRATIFY and its single risk factors, as well as age, gender and psychotropic medication; splitting the dataset into a learning and a validation sample for modelling fall-risk screening and independent, temporal validation. Geriatric clinic at an academic teaching hospital in Hamburg, Germany. 4,735 hospitalised patients ≥65 years. Sensitivity, specificity, positive and negative predictive value, Odds Ratios, Youden-Index and the rates of falls and fallers were calculated. There were 10.7% fallers, and the fall rate was 7.9/1,000 hospital days. In the learning sample, mental alteration (OR 2.9), fall history (OR 2.1), and insecure mobility (Barthel-Index items 'transfer' + 'walking' score = 5, 10 or 15) (OR 2.3) had the most strongest association to falls. The LUCAS Fall-Risk Screening uses these risk factors, and patients with ≥2 risk factors contributed to the high-risk group (30.9%). In the validation sample, STRATIFY SENS was 56.8, SPEC 59.6, PPV 13.5 and NPV 92.6 vs. LUCAS Fall-Risk Screening was SENS 46.0, SPEC 71.1, PPV 14.9 and NPV 92.3. Both the STRATIFY and the LUCAS Fall-Risk Screening showed comparable results in defining a high-risk group. Impaired mobility and cognitive status were closely associated to falls. The results do underscore the importance of functional status as essential fall-risk factor in older hospitalised patients.

Development and validation of a new questionnaire measuring treatment satisfaction in patients with non-valvular atrial fibrillation: SAFUCA®.

PubMed

Ruiz, Miguel A; González-Porras, José Ramón; Aranguren, José Luis; Franco, Eduardo; Villasante, Fernando; Tuñón, José; González-López, Tomás José; de Salas-Cansado, Marina; Soto, Javier

2017-03-01

To develop a new questionnaire with good psychometric properties to measure satisfaction with medical care in patients with non-valvular atrial fibrillation. The initial instrument was composed of 37 items, arranged in 6 dimensions: efficacy, ease and convenience, impact on daily activities, satisfaction with medical care, undesired effects of medication, and overall satisfaction. Items and dimensions were extracted from reviewing existing instruments, 3 focus groups with chronic patients, and a panel of 8 experts. Additionally, 3 visual analog scales measuring quality of life, effectiveness, and overall satisfaction were administered. A convenience sample of 119 patients was used for item reduction. Classic psychometric theory and item analysis techniques were used (exploratory factor and confirmatory factor analysis, test-retest, and correlation with visual scales). A validation sample of 230 patients was used to assess convergent validity, and an additional 220 patients sample was used to discriminate between treatment and compliance groups. The questionnaire was reduced in length to 25 items, but the impact dimension had split in treatment inconvenience and treatment control. Overall reliability was high (α = 0.861) with acceptable dimensional reliabilities (α = 0.764-0.908). Individual dimensions correlated to varying degrees. Test-retest correlations were high (r = 0.784-0.965), and correlations with visual and already validated scales were substantial. Differences were detected between antivitamin K and new-oral-anticoagulant treatments in several dimensions (p < 0.05). Treatment satisfaction was related with compliance. This new 25-item questionnaire has good psychometric properties for measuring satisfaction with medical care in patients with this condition. It is capable of detecting differences between different treatments.

Developing and Validating the Scale of Economic Self-Efficacy.

PubMed

Hoge, Gretchen L; Stylianou, Amanda M; Hetling, Andrea; Postmus, Judy L

2017-05-01

Experiencing intimate partner violence (IPV) and financial hardship are often intertwined. The dynamics of an abusive relationship may include economic abuse tactics that compromise a survivor's ability to work, pursue education, have access to financial resources, and establish financial skills, knowledge, and security. An increasingly common goal among programs serving IPV survivors is increasing financial empowerment through financial literacy. However, providing financial education alone may not be enough to improve financial behaviors. Psychological factors also play a role when individuals make financial choices. Economic self-efficacy focuses on the individual's perceived ability to perform economic or financial tasks, and may be considered a primary influence on one's ability to improve financial decisions and behaviors. The current study tests the reliability and validity of a Scale of Economic Self-Efficacy with a sample of female survivors of IPV. This study uses a calibration and validation analysis model including full and split-sample exploratory and confirmatory factor analyses, assesses for internal consistency, and examines correlation coefficients between economic self-efficacy, economic self-sufficiency, financial strain, and difficulty living with income. Findings indicate that the 10-item, unidimensional Scale of Economic Self-Efficacy demonstrates strong reliability and validity among this sample of IPV survivors. An ability to understand economic self-efficacy could facilitate individualized service approaches and allow practitioners to better support IPV survivors on their journey toward financial empowerment. Given the increase in programs focused on assets, financial empowerment, and economic well-being, the Scale of Economic Self-Efficacy has potential as a very timely and relevant tool in the design, implementation, and evaluation of such programs, and specifically for programs created for IPV survivors.

QSAR models for anti-malarial activity of 4-aminoquinolines.

PubMed

Masand, Vijay H; Toropov, Andrey A; Toropova, Alla P; Mahajan, Devidas T

2014-03-01

In the present study, predictive quantitative structure - activity relationship (QSAR) models for anti-malarial activity of 4-aminoquinolines have been developed. CORAL, which is freely available on internet (http://www.insilico.eu/coral), has been used as a tool of QSAR analysis to establish statistically robust QSAR model of anti-malarial activity of 4-aminoquinolines. Six random splits into the visible sub-system of the training and invisible subsystem of validation were examined. Statistical qualities for these splits vary, but in all these cases, statistical quality of prediction for anti-malarial activity was quite good. The optimal SMILES-based descriptor was used to derive the single descriptor based QSAR model for a data set of 112 aminoquinolones. All the splits had r(2)> 0.85 and r(2)> 0.78 for subtraining and validation sets, respectively. The three parametric multilinear regression (MLR) QSAR model has Q(2) = 0.83, R(2) = 0.84 and F = 190.39. The anti-malarial activity has strong correlation with presence/absence of nitrogen and oxygen at a topological distance of six.

Validation of SplitVectors Encoding for Quantitative Visualization of Large-Magnitude-Range Vector Fields

PubMed Central

Zhao, Henan; Bryant, Garnett W.; Griffin, Wesley; Terrill, Judith E.; Chen, Jian

2017-01-01

We designed and evaluated SplitVectors, a new vector field display approach to help scientists perform new discrimination tasks on large-magnitude-range scientific data shown in three-dimensional (3D) visualization environments. SplitVectors uses scientific notation to display vector magnitude, thus improving legibility. We present an empirical study comparing the SplitVectors approach with three other approaches - direct linear representation, logarithmic, and text display commonly used in scientific visualizations. Twenty participants performed three domain analysis tasks: reading numerical values (a discrimination task), finding the ratio between values (a discrimination task), and finding the larger of two vectors (a pattern detection task). Participants used both mono and stereo conditions. Our results suggest the following: (1) SplitVectors improve accuracy by about 10 times compared to linear mapping and by four times to logarithmic in discrimination tasks; (2) SplitVectors have no significant differences from the textual display approach, but reduce cluttering in the scene; (3) SplitVectors and textual display are less sensitive to data scale than linear and logarithmic approaches; (4) using logarithmic can be problematic as participants' confidence was as high as directly reading from the textual display, but their accuracy was poor; and (5) Stereoscopy improved performance, especially in more challenging discrimination tasks. PMID:28113469

Validation of SplitVectors Encoding for Quantitative Visualization of Large-Magnitude-Range Vector Fields.

PubMed

Henan Zhao; Bryant, Garnett W; Griffin, Wesley; Terrill, Judith E; Jian Chen

2017-06-01

We designed and evaluated SplitVectors, a new vector field display approach to help scientists perform new discrimination tasks on large-magnitude-range scientific data shown in three-dimensional (3D) visualization environments. SplitVectors uses scientific notation to display vector magnitude, thus improving legibility. We present an empirical study comparing the SplitVectors approach with three other approaches - direct linear representation, logarithmic, and text display commonly used in scientific visualizations. Twenty participants performed three domain analysis tasks: reading numerical values (a discrimination task), finding the ratio between values (a discrimination task), and finding the larger of two vectors (a pattern detection task). Participants used both mono and stereo conditions. Our results suggest the following: (1) SplitVectors improve accuracy by about 10 times compared to linear mapping and by four times to logarithmic in discrimination tasks; (2) SplitVectors have no significant differences from the textual display approach, but reduce cluttering in the scene; (3) SplitVectors and textual display are less sensitive to data scale than linear and logarithmic approaches; (4) using logarithmic can be problematic as participants' confidence was as high as directly reading from the textual display, but their accuracy was poor; and (5) Stereoscopy improved performance, especially in more challenging discrimination tasks.

Psychometric properties of the Chinese version of Spiritual Index of Well-Being in elderly Taiwanese.

PubMed

Wu, Li-Fen; Yang, Shu-Hui; Koo, Malcolm

2017-01-04

Spiritual well-being has become an increasingly important issue for the elderly people. The 12-item Spirituality Index of Well-Being (SIWB) is a well-validated instrument for assessing a patient's current spiritual state. However, the psychometric properties of the SIWB in the Chinese elderly populations are not known. Therefore, this study translated the SIWB into Chinese and evaluated its psychometric properties. The English version of the SIWB was first translated into Chinese based on the Brislin's translation model. The psychometric properties of the translated version of the SIWB (SIWB-C) was evaluated in 416 elderly Taiwanese recruited using a purposive sampling procedure from a medical center, a long-term care institution, and a community health center. Convergent validity was accessed using Pearson's correlation coefficients of the SIWB-C, the EQ-5D-3 L health-related quality of life scale, and the Geriatric Depression Scale-5 (GDS-5). Exploratory factor analysis with Varimax rotation was performed to determine the construct validity. Confirmatory factor analysis was conducted for verification of the quality of the factor structures and demonstrating the convergent validity of the SIWB-C. An internal consistency test based on the Cronbach's alpha coefficient and a stability test based on the Guttman split-half coefficient were also performed. Test-retest reliability was evaluated with intraclass correlation coefficient. Exploratory factor analysis confirmed the original two-dimensional structure of the scale. Confirmatory factor analysis indicated a well-fitting model and a fine convergent validity of the SIWB-C. The Cronbach's alpha coefficient and the Guttman split-half coefficient for the SIWB-C were 0.94 and 0.84, respectively. The correlations between the SIWB-C with EQ-5D-3 L and GDS-5 were 0.22 (p < 0.01) and 0.45 (p < 0.05), respectively. The intraclass correlation coefficient of the SIWB-C over a test-retest interval of two weeks was 0.989. The SIWB-C was found to be a potential useful measure of subjective spiritual well-being in elderly Taiwanese. Its application in assessing the spiritual well-being in Mandarin-speaking elderly population warrants further investigation.

Galaxy bias from galaxy–galaxy lensing in the DES science verification data

DOE PAGES

Prat, J.; Sánchez, C.; Miquel, R.; ...

2017-09-25

Here, we present a measurement of galaxy–galaxy lensing around a magnitude-limited (i AB < 22.5) sample of galaxies from the dark energy survey science verification (DES-SV) data. We split these lenses into three photometric-redshift bins from 0.2 to 0.8, and determine the product of the galaxy bias b and cross-correlation coefficient between the galaxy and dark matter overdensity fields r in each bin, using scales above 4 h –1 Mpc comoving, where we find the linear bias model to be valid given our current uncertainties. We compare our galaxy bias results from galaxy–galaxy lensing with those obtained from galaxy clusteringmore » and CMB lensing for the same sample of galaxies, and find our measurements to be in good agreement with those in Crocce et al., while, in the lowest redshift bin (z ~ 0.3), they show some tension with the findings in Giannantonio et al. We measure b · r to be 0.87 ± 0.11, 1.12 ± 0.16 and 1.24 ± 0.23, respectively, for the three redshift bins of width Δz = 0.2 in the range 0.2 < z < 0.8, defined with the photometric-redshift algorithm bpz. Using a different code to split the lens sample, tpz, leads to changes in the measured biases at the 10–20 per cent level, but it does not alter the main conclusion of this work: when comparing with Crocce et al. we do not find strong evidence for a cross-correlation parameter significantly below one in this galaxy sample, except possibly at the lowest redshift bin (z ~ 0.3), where we find r = 0.71 ± 0.11 when using tpz, and 0.83 ± 0.12 with bpz.« less

The Negative Consequences of Other Students’ Drinking: Inventory Development and Assessment of Differences by Student Characteristics and Risk Behaviors

PubMed Central

Rhodes, Scott D.; McCoy, Thomas P.; Omli, Morrow R.; Cohen, Gail M.; Wagoner, Kimberly G.; DuRant, Robert H.; Vissman, Aaron T.; Wolfson, Mark

2013-01-01

College students continue to report being disrupted by other students’ alcohol use. Objective: This study was designed to develop measures to document the consequences resulting from other students’ drinking and identify differences in experiencing these consequences by student characteristics and drinking behaviors. Study group: A stratified random sample of undergraduate students (N = 3,908) from ten universities in North Carolina, USA, completed a web-based assessment. Methods: Exploratory factor analysis (EFA) was performed on the random first split-half sample (n = 1,954) to identify factor structure. Confirmatory factor analysis (CFA) was performed on the remaining half sample (n = 1,954) using structural equation modeling. Results: EFA revealed two inventories: interpersonal and community consequences of others’ drinking inventories. CFA on the second split-half sample identified model fits for the two factor structure suggested by EFA. Of 3,908 participants, 78% reported experiencing one or more consequences due to others’ drinking during the past 30 days. Multivariable generalized linear mixed modeling further validated the inventories and resulted in several associations. Male students who reported getting drunk experienced significantly more interpersonal consequences from others’ drinking (p < .001). Minority students, students who lived on campus and students who reported getting drunk experienced significantly more community consequences from others’ drinking (p < .01). Conclusions: These findings demonstrate that 4 out of 5 college students experience consequences from others’ drinking, and consequences vary for different subgroups of students. Although these inventories should be tested further, these findings propose standardized measures that may be useful to assess the consequences of others’ drinking among college students. PMID:20306764

Galaxy bias from galaxy–galaxy lensing in the DES science verification data

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

Prat, J.; Sánchez, C.; Miquel, R.

Here, we present a measurement of galaxy–galaxy lensing around a magnitude-limited (i AB < 22.5) sample of galaxies from the dark energy survey science verification (DES-SV) data. We split these lenses into three photometric-redshift bins from 0.2 to 0.8, and determine the product of the galaxy bias b and cross-correlation coefficient between the galaxy and dark matter overdensity fields r in each bin, using scales above 4 h –1 Mpc comoving, where we find the linear bias model to be valid given our current uncertainties. We compare our galaxy bias results from galaxy–galaxy lensing with those obtained from galaxy clusteringmore » and CMB lensing for the same sample of galaxies, and find our measurements to be in good agreement with those in Crocce et al., while, in the lowest redshift bin (z ~ 0.3), they show some tension with the findings in Giannantonio et al. We measure b · r to be 0.87 ± 0.11, 1.12 ± 0.16 and 1.24 ± 0.23, respectively, for the three redshift bins of width Δz = 0.2 in the range 0.2 < z < 0.8, defined with the photometric-redshift algorithm bpz. Using a different code to split the lens sample, tpz, leads to changes in the measured biases at the 10–20 per cent level, but it does not alter the main conclusion of this work: when comparing with Crocce et al. we do not find strong evidence for a cross-correlation parameter significantly below one in this galaxy sample, except possibly at the lowest redshift bin (z ~ 0.3), where we find r = 0.71 ± 0.11 when using tpz, and 0.83 ± 0.12 with bpz.« less

Galaxy bias from galaxy-galaxy lensing in the DES science verification data

NASA Astrophysics Data System (ADS)

Prat, J.; Sánchez, C.; Miquel, R.; Kwan, J.; Blazek, J.; Bonnett, C.; Amara, A.; Bridle, S. L.; Clampitt, J.; Crocce, M.; Fosalba, P.; Gaztanaga, E.; Giannantonio, T.; Hartley, W. G.; Jarvis, M.; MacCrann, N.; Percival, W. J.; Ross, A. J.; Sheldon, E.; Zuntz, J.; Abbott, T. M. C.; Abdalla, F. B.; Annis, J.; Benoit-Lévy, A.; Bertin, E.; Brooks, D.; Burke, D. L.; Carnero Rosell, A.; Carrasco Kind, M.; Carretero, J.; Castander, F. J.; da Costa, L. N.; DePoy, D. L.; Desai, S.; Diehl, H. T.; Doel, P.; Eifler, T. F.; Evrard, A. E.; Fausti Neto, A.; Flaugher, B.; Frieman, J.; Gerdes, D. W.; Goldstein, D. A.; Gruen, D.; Gruendl, R. A.; Gutierrez, G.; Honscheid, K.; James, D. J.; Kuehn, K.; Kuropatkin, N.; Lahav, O.; Lima, M.; Marshall, J. L.; Melchior, P.; Menanteau, F.; Nord, B.; Plazas, A. A.; Reil, K.; Romer, A. K.; Roodman, A.; Sanchez, E.; Scarpine, V.; Schubnell, M.; Sevilla-Noarbe, I.; Smith, R. C.; Soares-Santos, M.; Sobreira, F.; Suchyta, E.; Swanson, M. E. C.; Tarle, G.; Thomas, D.; Walker, A. R.

2018-01-01

We present a measurement of galaxy-galaxy lensing around a magnitude-limited (iAB < 22.5) sample of galaxies from the dark energy survey science verification (DES-SV) data. We split these lenses into three photometric-redshift bins from 0.2 to 0.8, and determine the product of the galaxy bias b and cross-correlation coefficient between the galaxy and dark matter overdensity fields r in each bin, using scales above 4 h-1 Mpc comoving, where we find the linear bias model to be valid given our current uncertainties. We compare our galaxy bias results from galaxy-galaxy lensing with those obtained from galaxy clustering and CMB lensing for the same sample of galaxies, and find our measurements to be in good agreement with those in Crocce et al., while, in the lowest redshift bin (z ∼ 0.3), they show some tension with the findings in Giannantonio et al. We measure b · r to be 0.87 ± 0.11, 1.12 ± 0.16 and 1.24 ± 0.23, respectively, for the three redshift bins of width Δz = 0.2 in the range 0.2 < z < 0.8, defined with the photometric-redshift algorithm BPZ. Using a different code to split the lens sample, TPZ, leads to changes in the measured biases at the 10-20 per cent level, but it does not alter the main conclusion of this work: when comparing with Crocce et al. we do not find strong evidence for a cross-correlation parameter significantly below one in this galaxy sample, except possibly at the lowest redshift bin (z ∼ 0.3), where we find r = 0.71 ± 0.11 when using TPZ, and 0.83 ± 0.12 with BPZ.

Novel molecular subgroups for clinical classification and outcome prediction in childhood medulloblastoma: a cohort study.

PubMed

Schwalbe, Edward C; Lindsey, Janet C; Nakjang, Sirintra; Crosier, Stephen; Smith, Amanda J; Hicks, Debbie; Rafiee, Gholamreza; Hill, Rebecca M; Iliasova, Alice; Stone, Thomas; Pizer, Barry; Michalski, Antony; Joshi, Abhijit; Wharton, Stephen B; Jacques, Thomas S; Bailey, Simon; Williamson, Daniel; Clifford, Steven C

2017-07-01

International consensus recognises four medulloblastoma molecular subgroups: WNT (MB WNT ), SHH (MB SHH ), group 3 (MB Grp3 ), and group 4 (MB Grp4 ), each defined by their characteristic genome-wide transcriptomic and DNA methylomic profiles. These subgroups have distinct clinicopathological and molecular features, and underpin current disease subclassification and initial subgroup-directed therapies that are underway in clinical trials. However, substantial biological heterogeneity and differences in survival are apparent within each subgroup, which remain to be resolved. We aimed to investigate whether additional molecular subgroups exist within childhood medulloblastoma and whether these could be used to improve disease subclassification and prognosis predictions. In this retrospective cohort study, we assessed 428 primary medulloblastoma samples collected from UK Children's Cancer and Leukaemia Group (CCLG) treatment centres (UK), collaborating European institutions, and the UKCCSG-SIOP-PNET3 European clinical trial. An independent validation cohort (n=276) of archival tumour samples was also analysed. We analysed samples from patients with childhood medulloblastoma who were aged 0-16 years at diagnosis, and had central review of pathology and comprehensive clinical data. We did comprehensive molecular profiling, including DNA methylation microarray analysis, and did unsupervised class discovery of test and validation cohorts to identify consensus primary molecular subgroups and characterise their clinical and biological significance. We modelled survival of patients aged 3-16 years in patients (n=215) who had craniospinal irradiation and had been treated with a curative intent. Seven robust and reproducible primary molecular subgroups of childhood medulloblastoma were identified. MB WNT remained unchanged and each remaining consensus subgroup was split in two. MB SHH was split into age-dependent subgroups corresponding to infant (<4·3 years; MB SHH-Infant ; n=65) and childhood patients (≥4·3 years; MB SHH-Child ; n=38). MB Grp3 and MB Grp4 were each split into high-risk (MB Grp3-HR [n=65] and MB Grp4-HR [n=85]) and low-risk (MB Grp3-LR [n=50] and MB Grp4-LR [n=73]) subgroups. These biological subgroups were validated in the independent cohort. We identified features of the seven subgroups that were predictive of outcome. Cross-validated subgroup-dependent survival models, incorporating these novel subgroups along with secondary clinicopathological and molecular features and established disease risk-factors, outperformed existing disease risk-stratification schemes. These subgroup-dependent models stratified patients into four clinical risk groups for 5-year progression-free survival: favourable risk (54 [25%] of 215 patients; 91% survival [95% CI 82-100]); standard risk (50 [23%] patients; 81% survival [70-94]); high-risk (82 [38%] patients; 42% survival [31-56]); and very high-risk (29 [13%] patients; 28% survival [14-56]). The discovery of seven novel, clinically significant subgroups improves disease risk-stratification and could inform treatment decisions. These data provide a new foundation for future research and clinical investigations. Cancer Research UK, The Tom Grahame Trust, Star for Harris, Action Medical Research, SPARKS, The JGW Patterson Foundation, The INSTINCT network (co-funded by The Brain Tumour Charity, Great Ormond Street Children's Charity, and Children with Cancer UK). Copyright © 2017 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license. Published by Elsevier Ltd.. All rights reserved.

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

David A. King, CHP, PMP

Oak Ridge Associated Universities (ORAU), under the Oak Ridge Institute for Science and Education (ORISE) contract, collected split surface water samples with Nuclear Fuel Services (NFS) representatives on August 22, 2012. Representatives from the U.S. Nuclear Regulatory Commission and Tennessee Department of Environment and Conservation were also in attendance. Samples were collected at four surface water stations, as required in the approved Request for Technical Assistance number 11-018. These stations included Nolichucky River upstream (NRU), Nolichucky River downstream (NRD), Martin Creek upstream (MCU), and Martin Creek downstream (MCD). Both ORAU and NFS performed gross alpha and gross beta analyses. Themore » comparison of results using the duplicate error ratio (DER), also known as the normalized absolute difference. A DER ≤ 3 indicates that, at a 99% confidence interval, split sample results do not differ significantly when compared to their respective one standard deviation (sigma) uncertainty. The NFS split sample report does not specify the confidence level of reported uncertainties. Therefore, standard two sigma reporting is assumed and uncertainty values were divided by 1.96. A comparison of split sample results, using the DER equation, indicates one set with a DER greater than 3. A DER of 3.1 is calculated for gross alpha results from ORAU sample 5198W0003 and NFS sample MCU-310212003. The ORAU result is 0.98 ± 0.30 pCi/L (value ± 2 sigma) compared to the NFS result of -0.08 ± 0.60 pCi/L. Relatively high DER values are not unexpected for low (e.g., background) analyte concentrations analyzed by separate laboratories, as is the case here. It is noted, however, NFS uncertainties are at least twice the ORAU uncertainties, which contributes to the elevated DER value. Differences in ORAU and NFS minimum detectable activities are even more pronounced. comparison of ORAU and NFS split samples produces reasonably consistent results for low (e.g., background) concentrations.« less

Quasi-QSAR for mutagenic potential of multi-walled carbon-nanotubes.

PubMed

Toropov, Andrey A; Toropova, Alla P

2015-04-01

Available on the Internet, the CORAL software (http://www.insilico.eu/coral) has been used to build up quasi-quantitative structure-activity relationships (quasi-QSAR) for prediction of mutagenic potential of multi-walled carbon-nanotubes (MWCNTs). In contrast with the previous models built up by CORAL which were based on representation of the molecular structure by simplified molecular input-line entry system (SMILES) the quasi-QSARs based on the representation of conditions (not on the molecular structure) such as concentration, presence (absence) S9 mix, the using (or without the using) of preincubation were encoded by so-called quasi-SMILES. The statistical characteristics of these models (quasi-QSARs) for three random splits into the visible training set and test set and invisible validation set are the following: (i) split 1: n=13, r(2)=0.8037, q(2)=0.7260, s=0.033, F=45 (training set); n=5, r(2)=0.9102, s=0.071 (test set); n=6, r(2)=0.7627, s=0.044 (validation set); (ii) split 2: n=13, r(2)=0.6446, q(2)=0.4733, s=0.045, F=20 (training set); n=5, r(2)=0.6785, s=0.054 (test set); n=6, r(2)=0.9593, s=0.032 (validation set); and (iii) n=14, r(2)=0.8087, q(2)=0.6975, s=0.026, F=51 (training set); n=5, r(2)=0.9453, s=0.074 (test set); n=5, r(2)=0.8951, s=0.052 (validation set). Copyright © 2014 Elsevier Ltd. All rights reserved.

Monitoring protein-protein interactions using split synthetic renilla luciferase protein-fragment-assisted complementation.

PubMed

Paulmurugan, R; Gambhir, S S

2003-04-01

In this study we developed an inducible synthetic renilla luciferase protein-fragment-assisted complementation-based bioluminescence assay to quantitatively measure real time protein-protein interactions in mammalian cells. We identified suitable sites to generate fragments of N and C portions of the protein that yield significant recovered activity through complementation. We validate complementation-based activation of split synthetic renilla luciferase protein driven by the interaction of two strongly interacting proteins, MyoD and Id, in five different cell lines utilizing transient transfection studies. The expression level of the system was also modulated by tumor necrosis factor alpha through NFkappaB-promoter/enhancer elements used to drive expression of the N portion of synthetic renilla luciferase reporter gene. This new system should help in studying protein-protein interactions and when used with other split reporters (e.g., split firefly luciferase) should help to monitor different components of an intracellular network.

Monitoring Protein–Protein Interactions Using Split Synthetic Renilla Luciferase Protein-Fragment-Assisted Complementation

PubMed Central

Paulmurugan, R.; Gambhir, S. S.

2014-01-01

In this study we developed an inducible synthetic renilla luciferase protein-fragment-assisted complementation-based bioluminescence assay to quantitatively measure real time protein–protein interactions in mammalian cells. We identified suitable sites to generate fragments of N and C portions of the protein that yield significant recovered activity through complementation. We validate complementation-based activation of split synthetic renilla luciferase protein driven by the interaction of two strongly interacting proteins, MyoD and Id, in five different cell lines utilizing transient transfection studies. The expression level of the system was also modulated by tumor necrosis factor α through NFκB-promoter/enhancer elements used to drive expression of the N portion of synthetic renilla luciferase reporter gene. This new system should help in studying protein–protein interactions and when used with other split reporters (e.g., split firefly luciferase) should help to monitor different components of an intracellular network. PMID:12705589

The incremental value of troponin biomarkers in risk stratification of acute coronary syndromes: is the relationship multiplicative?

PubMed

Amin, Amit P; Nathan, Sandeep; Vassallo, Patricia; Calvin, James E

2009-05-20

To emphasize the importance of troponin in the context of a new score for risk stratifying acute coronary syndromes (ACS) patients. Although troponins have powerful prognostic value, current ACS scores do not fully capitalize this prognostic ability. Here, we weigh troponin status in a multiplicative manner to develop the TRACS score from previously published Rush score risk factors (RRF). 2,866 ACS patients (46.7% troponin positive) from 9 centers comprising the TRACS registry, were randomly split into derivation (n=1,422) and validation (n=1,444) cohorts. In the derivation sample, RRF sum was multiplied by 3 if troponins were positive to yield the TRACS score, which was grouped into five categories of 0-2, 3-5, 6-8, 9-11, 12-15 (multiples of 3). Predictive performance of this score to predict hospital death was ascertained in the validation sample. The TRACS score had ROC AUC of 0.71 in the validation cohort. Logistic regression, Kaplan-Meier analysis, likelihood-ratio and Bayesian Information Criterion (BIC) test indicated that weighing troponin status with 3 in the TRACS score improved the prediction of mortality. Hosmer-Lemeshow test indicated sound model fit. We demonstrate that weighing troponin as a multiple of 3 yields robust prognostication of hospital mortality in ACS patients, when used in the context of the TRACS score.

The Incremental Value of Troponin Biomarkers in Risk Stratification of Acute Coronary Syndromes: Is the Relationship Multiplicative?

PubMed Central

Amin, Amit P; Nathan, Sandeep; Vassallo, Patricia; Calvin, James E

2009-01-01

Structured Abstract Objective: To emphasize the importance of troponin in the context of a new score for risk stratifying acute coronary syndromes (ACS) patients. Although troponins have powerful prognostic value, current ACS scores do not fully capitalize this prognostic ability. Here, we weigh troponin status in a multiplicative manner to develop the TRACS score from previously published Rush score risk factors (RRF). Methods: 2,866 ACS patients (46.7% troponin positive) from 9 centers comprising the TRACS registry, were randomly split into derivation (n=1,422) and validation (n=1,444) cohorts. In the derivation sample, RRF sum was multiplied by 3 if troponins were positive to yield the TRACS score, which was grouped into five categories of 0-2, 3-5, 6-8, 9-11, 12-15 (multiples of 3). Predictive performance of this score to predict hospital death was ascertained in the validation sample. Results: The TRACS score had ROC AUC of 0.71 in the validation cohort. Logistic regression, Kaplan-Meier analysis, likelihood-ratio and Bayesian Information Criterion (BIC) test indicated that weighing troponin status with 3 in the TRACS score improved the prediction of mortality. Hosmer-Lemeshow test indicated sound model fit. Conclusions: We demonstrate that weighing troponin as a multiple of 3 yields robust prognostication of hospital mortality in ACS patients, when used in the context of the TRACS score. PMID:19557150

Scale for positive aspects of caregiving experience: development, reliability, and factor structure.

PubMed

Kate, N; Grover, S; Kulhara, P; Nehra, R

2012-06-01

OBJECTIVE. To develop an instrument (Scale for Positive Aspects of Caregiving Experience [SPACE]) that evaluates positive caregiving experience and assess its psychometric properties. METHODS. Available scales which assess some aspects of positive caregiving experience were reviewed and a 50-item questionnaire with a 5-point rating was constructed. In all, 203 primary caregivers of patients with severe mental disorders were asked to complete the questionnaire. Internal consistency, test-retest reliability, cross-language reliability, split-half reliability, and face validity were evaluated. Principal component factor analysis was run to assess the factorial validity of the scale. RESULTS. The scale developed as part of the study was found to have good internal consistency, test-retest reliability, cross-language reliability, split-half reliability, and face validity. Principal component factor analysis yielded a 4-factor structure, which also had good test-retest reliability and cross-language reliability. There was a strong correlation between the 4 factors obtained. CONCLUSION. The SPACE developed as part of this study has good psychometric properties.

Development and Validation of the Transgender Inclusive Behavior Scale (TIBS).

PubMed

Kattari, Shanna K; O'Connor, Ashley A; Kattari, Leonardo

2018-01-01

Transgender-inclusive behaviors are actions and communication supporting transgender individuals. Examples include using language not reinforcing the gender binary, asking for and using correct pronouns, creation of spaces that welcome members of the transgender community, and acknowledging cisgender (non-transgender) privilege. A survey was developed measuring this behavior in individuals to examine the impact of transgender-inclusive behavior and the potential effect of interventions on promoting inclusive behavior. Data were collected utilizing an online survey (N = 1,051). The sample was split in half to run two sets of cases in a principal components analysis. Analysis of the full sample showed Cronbach's alpha to be .93 (n = 918). Findings suggest that the Transgender Inclusive Behavior Scale (TIBS) may be a useful instrument for identifying behaviors related to being inclusive of transgender individuals, groups, and communities. It may also be used to measure behavior change before and after transgender-specific educational and behavioral interventions.

[Validity, reliability, and acceptability of the brief version of the self-management knowledge, attitude, and behavior assessment scale for diabetes patients].

PubMed

Wu, Y Z; Wang, W J; Feng, N P; Chen, B; Li, G C; Liu, J W; Liu, H L; Yang, Y Y

2016-07-06

To evaluate the validity, reliability, and acceptability of the brief version of the self-management knowledge, attitude, and behavior (KAB) assessment scale for diabetes patients. Diabetes patients who were managed at the Xinkaipu Community Health Service Center of Tianxin in Changsha, Hunan Province were selected for survey by cluster sampling. A total of 350 diabetes patients were surveyed using the brief scale to collect data on knowledge, attitudes, and behaviors of self-management. Content validity was evaluated by Pearson correlation coefficient between the brief scale and subscales of knowledge, attitude, and behavior. Structure validity was evaluated by factor analysis, and discrimination validity was evaluated by an independent sample t-test between the high-score and low-score groups. Reliability was tested by internal consistency reliability and split-half reliability. The evaluation indexes of internal consistency reliability were Cronbach's α coefficients, θ coefficient, and Ω coefficient. Acceptability was evaluated by valid response rate and completion time of the brief scale. A total of 346(98.9%) valid questionnaires were returned, with average survey time of (11.43±3.4) minutes. Average score of the brief scale was 78.85 ± 11.22; scores of the knowledge, attitude, and behavior subscales were 16.45 ± 4.42, 21.33 ± 2.03, and 41.07 ± 8.34, respectively. Pearson correlation coefficients between the brief scale and the knowledge, attitude, and behavior subscales were 0.92, 0.42, and 0.60, respectively; P-values were all less than 0.01, indicating that the face validity and content validity of the brief scale were achieved to a good level. The common factor cumulative variance contribution rate of the brief scale and three subscales was from 53.66% to 61.75%, which achieved more than 50% of the approved standard. There were 11 common factors; 41 of the total 42 items had factor loadings above 0.40 in their relevant common factor, indicating that the brief scale and three subscales had good construct validity. Patients were divided into a high-score group and a low-score group, then scores of the brief scale and three subscales were compared between the groups using a t-test. The results were all significant, indicating that the brief scale and three subscales had good discriminate validity. Mean scores of the brief scale and three subscales of the high-score group were 91.55±6.81, 19.51±2.17, 22.74±1.88, and 49.30±6.20, respectively; these were higher than the low-score group (65.89±5.79, 12.29±4.76, 20.22±1.88, and 33.39±6.17, respectively) with t-values 27.76, 13.31, 9.20, and 17.56 (P-values were less than 0.001). The Cronbach's α coefficient, θ coefficient, Ω coefficient, and split-half reliability of the brief scale were 0.83, 0.87, 0.96, and 0.84, respectively. These values for the three subscales were all above 0.70, except for the θ coefficient of the attitude subscale with 0.64, indicating that the brief scale and three subscales had acceptable internal consistency reliability. The brief version of the diabetes self-management knowledge, attitude, and behavior assessment scale showed good acceptability, validity, and reliability, to responsibly evaluate self-management KAB among patients with diabetes.

Performance of the split-symbol moments SNR estimator in the presence of inter-symbol interference

NASA Technical Reports Server (NTRS)

Shah, B.; Hinedi, S.

1989-01-01

The Split-Symbol Moments Estimator (SSME) is an algorithm that is designed to estimate symbol signal-to-noise ratio (SNR) in the presence of additive white Gaussian noise (AWGN). The performance of the SSME algorithm in band-limited channels is examined. The effects of the resulting inter-symbol interference (ISI) are quantified. All results obtained are in closed form and can be easily evaluated numerically for performance prediction purposes. Furthermore, they are validated through digital simulations.

String splitting and strong coupling meson decay.

PubMed

Cotrone, A L; Martucci, L; Troost, W

2006-04-14

We study the decay of high spin mesons using the gauge-string theory correspondence. The rate of the process is calculated by studying the splitting of a macroscopic string intersecting a D-brane. The result is applied to the decay of mesons in N=4 super Yang-Mills theory with a small number of flavors and in a gravity dual of large N QCD. In QCD the decay of high spin mesons is found to be heavily suppressed in the regime of validity of the supergravity description.

FAST TRACK COMMUNICATION: Gyration mode splitting in magnetostatically coupled magnetic vortices in an array

NASA Astrophysics Data System (ADS)

Barman, Anjan; Barman, Saswati; Kimura, T.; Fukuma, Y.; Otani, Y.

2010-10-01

We present the experimental observation of gyration mode splitting by the time-resolved magneto-optical Kerr effect in an array consisting of magnetostatically coupled Ni81Fe19 discs of 1 µm diameter, 50 nm thickness and inter-disc separations varying between 150 and 270 nm. A splitting of the vortex core gyration mode is observed when the inter-disc separation is 200 nm or less and the splitting is controllable by a bias magnetic field. The observed mode splitting is interpreted by micromagnetic simulations as the normal modes of the vortex cores analogous to the coupled classical oscillators. The splitting depends upon the strength of the inter-disc magnetostatic coupling mediated by magnetic side charges, which depends strongly on the magnetic ground states of the samples.

Rasch analysis of the Patient Rated Elbow Evaluation questionnaire.

PubMed

Vincent, Joshua I; MacDermid, Joy C; King, Graham J W; Grewal, Ruby

2015-06-20

The Patient Rated Elbow Evaluation (PREE) was developed as an elbow joint specific measure of pain and disability and validated with classical psychometric methods. More recently, Rasch analysis has contributed new methods for analyzing the clinical measurement properties of self-report outcome measures. The objective of the study was to determine aspects of validity of the PREE using the Rasch model to assess the overall fit of the PREE data, the response scaling, individual item fit, differential item functioning (DIF), local dependency, unidimensionality and person separation index (PSI). A convenience sample of 236 patients (Age range 21-79 years; M: F- 97:139) with elbow disorders were recruited from the Roth│McFarlane Hand and Upper Limb Centre, London, Ontario, Canada. The baseline scores of the PREE were used. Rasch analysis was conducted using RUMM 2030 software on the 3 sub scales of the PREE separately. The 3 sub scales showed misfit initially with disordered thresholds on17 out of 20 items), uniform DIF was observed for two items ("Carrying a 10lbs object" from specific activities subscale for age group; and "household work" from the usual activities subscale for gender); multidimensionality and local dependency. The Pain subscale satisfied Rasch expectations when item 2 "Pain - At rest" was split for age group, while the usual activities subscale readily stood up to Rasch requirements when the item 2 "household work" was split for gender. The specific activities subscale demonstrated fit to the Rasch model when sub test analysis accounted for local dependency. All three subscales of the PREE were well targeted and had high reliability (PSI >0.80). The three subscales of the PREE appear to be robust when tested against the Rasch model when subject to a few alterations. The value of changing the 0-10 format is questionable given its widespread use; further Rasch-based analysis of whether these findings are stable in other samples is warranted.

Elders Health Empowerment Scale: Spanish adaptation and psychometric analysis.

PubMed

Serrani Azcurra, Daniel Jorge Luis

2014-01-01

Empowerment refers to patient skills that allow them to become primary decision-makers in control of daily self-management of health problems. As important the concept as it is, particularly for elders with chronic diseases, few available instruments have been validated for use with Spanish speaking people. Translate and adapt the Health Empowerment Scale (HES) for a Spanish-speaking older adults sample and perform its psychometric validation. The HES was adapted based on the Diabetes Empowerment Scale-Short Form. Where "diabetes" was mentioned in the original tool, it was replaced with "health" terms to cover all kinds of conditions that could affect health empowerment. Statistical and Psychometric Analyses were conducted on 648 urban-dwelling seniors. The HES had an acceptable internal consistency with a Cronbach's α of 0.89. The convergent validity was supported by significant Pearson's Coefficient correlations between the HES total and item scores and the General Self Efficacy Scale (r= 0.77), Swedish Rheumatic Disease Empowerment Scale (r= 0.69) and Making Decisions Empowerment Scale (r= 0.70). Construct validity was evaluated using item analysis, half-split test and corrected item to total correlation coefficients; with good internal consistency (α> 0.8). The content validity was supported by Scale and Item Content Validity Index of 0.98 and 1.0, respectively. HES had acceptable face validity and reliability coefficients; which added to its ease administration and users' unbiased comprehension, could set it as a suitable tool in evaluating elder's outpatient empowerment-based medical education programs.

Elders Health Empowerment Scale

PubMed Central

2014-01-01

Introduction: Empowerment refers to patient skills that allow them to become primary decision-makers in control of daily self-management of health problems. As important the concept as it is, particularly for elders with chronic diseases, few available instruments have been validated for use with Spanish speaking people. Objective: Translate and adapt the Health Empowerment Scale (HES) for a Spanish-speaking older adults sample and perform its psychometric validation. Methods: The HES was adapted based on the Diabetes Empowerment Scale-Short Form. Where "diabetes" was mentioned in the original tool, it was replaced with "health" terms to cover all kinds of conditions that could affect health empowerment. Statistical and Psychometric Analyses were conducted on 648 urban-dwelling seniors. Results: The HES had an acceptable internal consistency with a Cronbach's α of 0.89. The convergent validity was supported by significant Pearson's Coefficient correlations between the HES total and item scores and the General Self Efficacy Scale (r= 0.77), Swedish Rheumatic Disease Empowerment Scale (r= 0.69) and Making Decisions Empowerment Scale (r= 0.70). Construct validity was evaluated using item analysis, half-split test and corrected item to total correlation coefficients; with good internal consistency (α> 0.8). The content validity was supported by Scale and Item Content Validity Index of 0.98 and 1.0, respectively. Conclusions: HES had acceptable face validity and reliability coefficients; which added to its ease administration and users' unbiased comprehension, could set it as a suitable tool in evaluating elder's outpatient empowerment-based medical education programs. PMID:25767307

Identification of Heterogeneous Cognitive Subgroups in Community-Dwelling Older Adults: A Latent Class Analysis of the Einstein Aging Study.

PubMed

Zammit, Andrea R; Hall, Charles B; Lipton, Richard B; Katz, Mindy J; Muniz-Terrera, Graciela

2018-05-01

The aim of this study was to identify natural subgroups of older adults based on cognitive performance, and to establish each subgroup's characteristics based on demographic factors, physical function, psychosocial well-being, and comorbidity. We applied latent class (LC) modeling to identify subgroups in baseline assessments of 1345 Einstein Aging Study (EAS) participants free of dementia. The EAS is a community-dwelling cohort study of 70+ year-old adults living in the Bronx, NY. We used 10 neurocognitive tests and 3 covariates (age, sex, education) to identify latent subgroups. We used goodness-of-fit statistics to identify the optimal class solution and assess model adequacy. We also validated our model using two-fold split-half cross-validation. The sample had a mean age of 78.0 (SD=5.4) and a mean of 13.6 years of education (SD=3.5). A 9-class solution based on cognitive performance at baseline was the best-fitting model. We characterized the 9 identified classes as (i) disadvantaged, (ii) poor language, (iii) poor episodic memory and fluency, (iv) poor processing speed and executive function, (v) low average, (vi) high average, (vii) average, (viii) poor executive and poor working memory, (ix) elite. The cross validation indicated stable class assignment with the exception of the average and high average classes. LC modeling in a community sample of older adults revealed 9 cognitive subgroups. Assignment of subgroups was reliable and associated with external validators. Future work will test the predictive validity of these groups for outcomes such as Alzheimer's disease, vascular dementia and death, as well as markers of biological pathways that contribute to cognitive decline. (JINS, 2018, 24, 511-523).

Design and analysis of unequal split Bagley power dividers

NASA Astrophysics Data System (ADS)

Abu-Alnadi, Omar; Dib, Nihad; Al-Shamaileh, Khair; Sheta, Abdelfattah

2015-03-01

In this article, we propose a general design procedure to develop unequal split Bagley power dividers (BPDs). Based on the mathematical approach carried out in the insight of simple circuit and transmission line theories, exact design equations for 3-way and 5-way BPDs are derived. Utilising the developed equations leads to power dividers with the ability of offering different output power ratios through a suitable choice of the characteristic impedances of the interconnecting transmission lines. For verification purposes, a 1:2:1 3-way, 1:2:1:2:1 5-way and 1:3:1:3:1 5-way BPDs are designed and fabricated. The experimental and full-wave simulation results prove the validity of the designed unequal split BPDs.

Operational Testing of Satellite based Hydrological Model (SHM)

NASA Astrophysics Data System (ADS)

Gaur, Srishti; Paul, Pranesh Kumar; Singh, Rajendra; Mishra, Ashok; Gupta, Praveen Kumar; Singh, Raghavendra P.

2017-04-01

Incorporation of the concept of transposability in model testing is one of the prominent ways to check the credibility of a hydrological model. Successful testing ensures ability of hydrological models to deal with changing conditions, along with its extrapolation capacity. For a newly developed model, a number of contradictions arises regarding its applicability, therefore testing of credibility of model is essential to proficiently assess its strength and limitations. This concept emphasizes to perform 'Hierarchical Operational Testing' of Satellite based Hydrological Model (SHM), a newly developed surface water-groundwater coupled model, under PRACRITI-2 program initiated by Space Application Centre (SAC), Ahmedabad. SHM aims at sustainable water resources management using remote sensing data from Indian satellites. It consists of grid cells of 5km x 5km resolution and comprises of five modules namely: Surface Water (SW), Forest (F), Snow (S), Groundwater (GW) and Routing (ROU). SW module (functions in the grid cells with land cover other than forest and snow) deals with estimation of surface runoff, soil moisture and evapotranspiration by using NRCS-CN method, water balance and Hragreaves method, respectively. The hydrology of F module is dependent entirely on sub-surface processes and water balance is calculated based on it. GW module generates baseflow (depending on water table variation with the level of water in streams) using Boussinesq equation. ROU module is grounded on a cell-to-cell routing technique based on the principle of Time Variant Spatially Distributed Direct Runoff Hydrograph (SDDH) to route the generated runoff and baseflow by different modules up to the outlet. For this study Subarnarekha river basin, flood prone zone of eastern India, has been chosen for hierarchical operational testing scheme which includes tests under stationary as well as transitory conditions. For this the basin has been divided into three sub-basins using three flow gauging sites as reference, viz., Muri, Jamshedpur and Ghatshila. Individual model set-up has been prepared for these sub-basins and calibration and validation using Split-sample test, first level of operational testing scheme is in progress. Subsequently for geographic transposability, Proxy-basin test will be done using Muri and Jamshedpur as proxy basins. Climatic transposability will be tested for dry and wet years using Differential split-sample test. For incorporating both geographic and climatic transposability Proxy-basin differential split sample test will be used. For quantitative evaluation of SHM, during Split-sample test Nash-Sutcliffe efficiency (NSE), Coefficient of Determination (R R^2)) and Percent BIAS (PBIAS) are being used. However, for transposability, a productive approach involving these performance measures, i.e. NSE*R R^2)*PBIAS will be used to decide the best value of parameters. Keywords: SHM, credibility, operational testing, transposability.

MMPI-2-RF characteristics of individuals with interstitial cystitis.

PubMed

Fazio, Rachel L; Wunderlich, Ted; Wilson, Nicolas; Akeson, Steven

2014-11-01

This study aimed to describe the psychological functioning of interstitial cystitis/bladder pain syndrome patients utilizing MMPI-2-RF scoring. The MMPI-2 was administered to 60 individuals who reported a diagnosis of IC. Responses were scored in the MMPI-2-RF format. Fifty-one protocols were deemed valid. Elevations were discovered on scales FBS-r (symptom validity), RC1 (somatic complaints), and MLS (malaise). Participants were split into two groups based on extreme elevations on RC1; the high RC1 group produced higher scores on 39 scales including clinically significant elevations on 17 scales. Over 25% of this sample had an emotional component to their physical concerns. This knowledge about the psychological characteristics of IC patients may have clinical utility for physicians and other treatment providers. The results argue strongly for psychological evaluation as a component of IC diagnosis and treatment. Those with significant emotional overlay to their somatic complaints may be best managed through psychological interventions and minimally invasive treatments. Copyright © 2014 Elsevier Inc. All rights reserved.

Investigating the Reliability and Factor Structure of Kalichman's "Survey 2: Research Misconduct" Questionnaire: A Post Hoc Analysis Among Biomedical Doctoral Students in Scandinavia.

PubMed

Holm, Søren; Hofmann, Bjørn

2017-10-01

A precondition for reducing scientific misconduct is evidence about scientists' attitudes. We need reliable survey instruments, and this study investigates the reliability of Kalichman's "Survey 2: research misconduct" questionnaire. The study is a post hoc analysis of data from three surveys among biomedical doctoral students in Scandinavia (2010-2015). We perform reliability analysis, and exploratory and confirmatory factor analysis using a split-sample design as a partial validation. The results indicate that a reliable 13-item scale can be formed (Cronbach's α = .705), and factor analysis indicates that there are four reliable subscales each tapping a different construct: (a) general attitude to misconduct (α = .768), (b) attitude to personal misconduct (α = .784), (c) attitude to whistleblowing (α = .841), and (d) attitude to blameworthiness/punishment (α = .877). A full validation of the questionnaire requires further research. We, nevertheless, hope that the results will facilitate the increased use of the questionnaire in research.

Does rational selection of training and test sets improve the outcome of QSAR modeling?

PubMed

Martin, Todd M; Harten, Paul; Young, Douglas M; Muratov, Eugene N; Golbraikh, Alexander; Zhu, Hao; Tropsha, Alexander

2012-10-22

Prior to using a quantitative structure activity relationship (QSAR) model for external predictions, its predictive power should be established and validated. In the absence of a true external data set, the best way to validate the predictive ability of a model is to perform its statistical external validation. In statistical external validation, the overall data set is divided into training and test sets. Commonly, this splitting is performed using random division. Rational splitting methods can divide data sets into training and test sets in an intelligent fashion. The purpose of this study was to determine whether rational division methods lead to more predictive models compared to random division. A special data splitting procedure was used to facilitate the comparison between random and rational division methods. For each toxicity end point, the overall data set was divided into a modeling set (80% of the overall set) and an external evaluation set (20% of the overall set) using random division. The modeling set was then subdivided into a training set (80% of the modeling set) and a test set (20% of the modeling set) using rational division methods and by using random division. The Kennard-Stone, minimal test set dissimilarity, and sphere exclusion algorithms were used as the rational division methods. The hierarchical clustering, random forest, and k-nearest neighbor (kNN) methods were used to develop QSAR models based on the training sets. For kNN QSAR, multiple training and test sets were generated, and multiple QSAR models were built. The results of this study indicate that models based on rational division methods generate better statistical results for the test sets than models based on random division, but the predictive power of both types of models are comparable.

Spatial and Temporal Control Contribute to Step Length Asymmetry during Split-Belt Adaptation and Hemiparetic Gait

PubMed Central

Finley, James M.; Long, Andrew; Bastian, Amy J.; Torres-Oviedo, Gelsy

2014-01-01

Background Step length asymmetry (SLA) is a common hallmark of gait post-stroke. Though conventionally viewed as a spatial deficit, SLA can result from differences in where the feet are placed relative to the body (spatial strategy), the timing between foot-strikes (step time strategy), or the velocity of the body relative to the feet (step velocity strategy). Objective The goal of this study was to characterize the relative contributions of each of these strategies to SLA. Methods We developed an analytical model that parses SLA into independent step position, step time, and step velocity contributions. This model was validated by reproducing SLA values for twenty-five healthy participants when their natural symmetric gait was perturbed on a split-belt treadmill moving at either a 2:1 or 3:1 belt-speed ratio. We then applied the validated model to quantify step position, step time, and step velocity contributions to SLA in fifteen stroke survivors while walking at their self-selected speed. Results SLA was predicted precisely by summing the derived contributions, regardless of the belt-speed ratio. Although the contributions to SLA varied considerably across our sample of stroke survivors, the step position contribution tended to oppose the other two – possibly as an attempt to minimize the overall SLA. Conclusions Our results suggest that changes in where the feet are placed or changes in interlimb timing could be used as compensatory strategies to reduce overall SLA in stroke survivors. These results may allow clinicians and researchers to identify patient-specific gait abnormalities and personalize their therapeutic approaches accordingly. PMID:25589580

Multi-Reader ROC studies with Split-Plot Designs: A Comparison of Statistical Methods

PubMed Central

Obuchowski, Nancy A.; Gallas, Brandon D.; Hillis, Stephen L.

2012-01-01

Rationale and Objectives Multi-reader imaging trials often use a factorial design, where study patients undergo testing with all imaging modalities and readers interpret the results of all tests for all patients. A drawback of the design is the large number of interpretations required of each reader. Split-plot designs have been proposed as an alternative, in which one or a subset of readers interprets all images of a sample of patients, while other readers interpret the images of other samples of patients. In this paper we compare three methods of analysis for the split-plot design. Materials and Methods Three statistical methods are presented: Obuchowski-Rockette method modified for the split-plot design, a newly proposed marginal-mean ANOVA approach, and an extension of the three-sample U-statistic method. A simulation study using the Roe-Metz model was performed to compare the type I error rate, power and confidence interval coverage of the three test statistics. Results The type I error rates for all three methods are close to the nominal level but tend to be slightly conservative. The statistical power is nearly identical for the three methods. The coverage of 95% CIs fall close to the nominal coverage for small and large sample sizes. Conclusions The split-plot MRMC study design can be statistically efficient compared with the factorial design, reducing the number of interpretations required per reader. Three methods of analysis, shown to have nominal type I error rate, similar power, and nominal CI coverage, are available for this study design. PMID:23122570

Multi-reader ROC studies with split-plot designs: a comparison of statistical methods.

PubMed

Obuchowski, Nancy A; Gallas, Brandon D; Hillis, Stephen L

2012-12-01

Multireader imaging trials often use a factorial design, in which study patients undergo testing with all imaging modalities and readers interpret the results of all tests for all patients. A drawback of this design is the large number of interpretations required of each reader. Split-plot designs have been proposed as an alternative, in which one or a subset of readers interprets all images of a sample of patients, while other readers interpret the images of other samples of patients. In this paper, the authors compare three methods of analysis for the split-plot design. Three statistical methods are presented: the Obuchowski-Rockette method modified for the split-plot design, a newly proposed marginal-mean analysis-of-variance approach, and an extension of the three-sample U-statistic method. A simulation study using the Roe-Metz model was performed to compare the type I error rate, power, and confidence interval coverage of the three test statistics. The type I error rates for all three methods are close to the nominal level but tend to be slightly conservative. The statistical power is nearly identical for the three methods. The coverage of 95% confidence intervals falls close to the nominal coverage for small and large sample sizes. The split-plot multireader, multicase study design can be statistically efficient compared to the factorial design, reducing the number of interpretations required per reader. Three methods of analysis, shown to have nominal type I error rates, similar power, and nominal confidence interval coverage, are available for this study design. Copyright © 2012 AUR. All rights reserved.

Dynamic behavior of geometrically complex hybrid composite samples in a Split-Hopkinson Pressure Bar system

NASA Astrophysics Data System (ADS)

Pouya, M.; Balasubramaniam, S.; Sharafiev, S.; F-X Wagner, M.

2018-06-01

The interfaces between layered materials play an important role for the overall mechanical behavior of hybrid composites, particularly during dynamic loading. Moreover, in complex-shaped composites, interfacial failure is strongly affected by the geometry and size of these contact interfaces. As preliminary work for the design of a novel sample geometry that allows to analyze wave reflection phenomena at the interfaces of such materials, a series of experiments using a Split-Hopkinson Pressure Bar technique was performed on five different sample geometries made of a monomaterial steel. A complementary explicit finite element model of the Split-Hopkinson Pressure Bar system was developed and the same sample geometries were studied numerically. The simulated input, reflected and transmitted elastic wave pulses were analyzed for the different sample geometries and were found to agree well with the experimental results. Additional simulations using different composite layers of steel and aluminum (with the same sample geometries) were performed to investigate the effect of material variation on the propagated wave pulses. The numerical results show that the reflected and transmitted wave pulses systematically depend on the sample geometry, and that elastic wave pulse propagation is affected by the properties of individual material layers.

Validated hydrophilic interaction LC-MS/MS method for simultaneous quantification of dacarbazine and 5-amino-4-imidazole-carboxamide in human plasma.

PubMed

Liu, Yanhong; Zhang, Weihua; Yang, Yuhui

2008-10-19

A hydrophilic interaction high performance liquid chromatography-tandem mass spectrometric method has been developed and validated for simultaneous quantification of dacarbazine (DTIC) and its terminal metabolite, 5-amino-4-imidazole-carboxamide (AIC) in human plasma. The plasma samples are first extracted by a C8+SCX mixed-mode 96-well plate to extend the extraction stability of DTIC and AIC. The extracted residues are further cleaned by a primary and secondary amine (PSA) adsorbent for minimization of matrix effect. Analyses are done on an Amide-80 HPLC column coupled to a tandem mass spectrometer fitted with an atmospheric pressure turbo ion spray ionization interface in the positive-ion mode. Both DTIC and AIC have reproducible retention times on the Amide-80 HPLC column. This type of column not only has an excellent column life (over 4000 injections), but also has zero carryover effect. The injection volume should be limited at 10 microL or less to avoid the peak splitting. The validated concentration ranges are from 0.5 to 500 ng/mL for DTIC and from 2.0 to 500 ng/mL for AIC. The validated method has been successfully applied to determine the pharmacokinetic profiles for human patients receiving DTIC infusions.

Predicting Job Performance for the Visually Impaired: Validity of the Fine Finger Dexterity Work Task.

ERIC Educational Resources Information Center

Giesen, J. Martin; And Others

The study was designed to determine the reliability and criterion validity of a psychomotor performance test (the Fine Finger Dexterity Work Task Unit) with 40 partially or totally blind adults. Reliability was established by using the test-retest method. A supervisory rating was developed and the reliability established by using the split-half…

Multi-dimensional Upwind Fluctuation Splitting Scheme with Mesh Adaption for Hypersonic Viscous Flow. Degree awarded by Virginia Polytechnic Inst. and State Univ., 9 Nov. 2001

NASA Technical Reports Server (NTRS)

Wood, William A., III

2002-01-01

A multi-dimensional upwind fluctuation splitting scheme is developed and implemented for two-dimensional and axisymmetric formulations of the Navier-Stokes equations on unstructured meshes. Key features of the scheme are the compact stencil, full upwinding, and non-linear discretization which allow for second-order accuracy with enforced positivity. Throughout, the fluctuation splitting scheme is compared to a current state-of-the-art finite volume approach, a second-order, dual mesh upwind flux difference splitting scheme (DMFDSFV), and is shown to produce more accurate results using fewer computer resources for a wide range of test cases. A Blasius flat plate viscous validation case reveals a more accurate upsilon-velocity profile for fluctuation splitting, and the reduced artificial dissipation production is shown relative to DMFDSFV. Remarkably, the fluctuation splitting scheme shows grid converged skin friction coefficients with only five points in the boundary layer for this case. The second half of the report develops a local, compact, anisotropic unstructured mesh adaptation scheme in conjunction with the multi-dimensional upwind solver, exhibiting a characteristic alignment behavior for scalar problems. The adaptation strategy is extended to the two-dimensional and axisymmetric Navier-Stokes equations of motion through the concept of fluctuation minimization.

Casemix classification payment for sub-acute and non-acute inpatient care, Thailand.

PubMed

Khiaocharoen, Orathai; Pannarunothai, Supasit; Zungsontiporn, Chairoj; Riewpaiboon, Wachara

2010-07-01

There is a need to develop other casemix classifications, apart from DRG for sub-acute and non-acute inpatient care payment mechanism in Thailand. To develop a casemix classification for sub-acute and non-acute inpatient service. The study began with developing a classification system, analyzing cost, assigning payment weights, and ended with testing the validity of this new casemix system. Coefficient of variation, reduction in variance, linear regression, and split-half cross-validation were employed. The casemix for sub-acute and non-acute inpatient services contained 98 groups. Two percent of them had a coefficient of variation of the cost of higher than 1.5. The reduction in variance of cost after the classification was 32%. Two classification variables (physical function and the rehabilitation impairment categories) were key determinants of the cost (adjusted R2 = 0.749, p = .001). Validity results of split-half cross-validation of sub-acute and non-acute inpatient service were high. The present study indicated that the casemix for sub-acute and non-acute inpatient services closely predicted the hospital resource use and should be further developed for payment of the inpatients sub-acute and non-acute phase.

Correcting for Optimistic Prediction in Small Data Sets

PubMed Central

Smith, Gordon C. S.; Seaman, Shaun R.; Wood, Angela M.; Royston, Patrick; White, Ian R.

2014-01-01

The C statistic is a commonly reported measure of screening test performance. Optimistic estimation of the C statistic is a frequent problem because of overfitting of statistical models in small data sets, and methods exist to correct for this issue. However, many studies do not use such methods, and those that do correct for optimism use diverse methods, some of which are known to be biased. We used clinical data sets (United Kingdom Down syndrome screening data from Glasgow (1991–2003), Edinburgh (1999–2003), and Cambridge (1990–2006), as well as Scottish national pregnancy discharge data (2004–2007)) to evaluate different approaches to adjustment for optimism. We found that sample splitting, cross-validation without replication, and leave-1-out cross-validation produced optimism-adjusted estimates of the C statistic that were biased and/or associated with greater absolute error than other available methods. Cross-validation with replication, bootstrapping, and a new method (leave-pair-out cross-validation) all generated unbiased optimism-adjusted estimates of the C statistic and had similar absolute errors in the clinical data set. Larger simulation studies confirmed that all 3 methods performed similarly with 10 or more events per variable, or when the C statistic was 0.9 or greater. However, with lower events per variable or lower C statistics, bootstrapping tended to be optimistic but with lower absolute and mean squared errors than both methods of cross-validation. PMID:24966219

Sampling the isothermal-isobaric ensemble by Langevin dynamics

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

Gao, Xingyu; Institute of Applied Physics and Computational Mathematics, Fenghao East Road 2, Beijing 100094; CAEP Software Center for High Performance Numerical Simulation, Huayuan Road 6, Beijing 100088

2016-03-28

We present a new method of conducting fully flexible-cell molecular dynamics simulation in isothermal-isobaric ensemble based on Langevin equations of motion. The stochastic coupling to all particle and cell degrees of freedoms is introduced in a correct way, in the sense that the stationary configurational distribution is proved to be consistent with that of the isothermal-isobaric ensemble. In order to apply the proposed method in computer simulations, a second order symmetric numerical integration scheme is developed by Trotter’s splitting of the single-step propagator. Moreover, a practical guide of choosing working parameters is suggested for user specified thermo- and baro-coupling timemore » scales. The method and software implementation are carefully validated by a numerical example.« less

Optimal energy-splitting method for an open-loop liquid crystal adaptive optics system.

PubMed

Cao, Zhaoliang; Mu, Quanquan; Hu, Lifa; Liu, Yonggang; Peng, Zenghui; Yang, Qingyun; Meng, Haoran; Yao, Lishuang; Xuan, Li

2012-08-13

A waveband-splitting method is proposed for open-loop liquid crystal adaptive optics systems (LC AOSs). The proposed method extends the working waveband, splits energy flexibly, and improves detection capability. Simulated analysis is performed for a waveband in the range of 350 nm to 950 nm. The results show that the optimal energy split is 7:3 for the wavefront sensor (WFS) and for the imaging camera with the waveband split into 350 nm to 700 nm and 700 nm to 950 nm, respectively. A validation experiment is conducted by measuring the signal-to-noise ratio (SNR) of the WFS and the imaging camera. The results indicate that for the waveband-splitting method, the SNR of WFS is approximately equal to that of the imaging camera with a variation in the intensity. On the other hand, the SNR of the WFS is significantly different from that of the imaging camera for the polarized beam splitter energy splitting scheme. Therefore, the waveband-splitting method is more suitable for an open-loop LC AOS. An adaptive correction experiment is also performed on a 1.2-meter telescope. A star with a visual magnitude of 4.45 is observed and corrected and an angular resolution ability of 0.31″ is achieved. A double star with a combined visual magnitude of 4.3 is observed as well, and its two components are resolved after correction. The results indicate that the proposed method can significantly improve the detection capability of an open-loop LC AOS.

Development and validation of a tool to assess knowledge and attitudes towards generic medicines among students in Greece: The ATtitude TOwards GENerics (ATTOGEN) questionnaire

PubMed Central

Katsari, Vasiliki; Niakas, Dimitris

2017-01-01

Introduction The use of generic medicines is a cost-effective policy, often dictated by fiscal restraints. To our knowledge, no fully validated tool exploring the students’ knowledge and attitudes towards generic medicines exists. The aim of our study was to develop and validate a questionnaire exploring the knowledge and attitudes of M.Sc. in Health Care Management students and recent alumni’s towards generic drugs in Greece. Materials and methods The development of the questionnaire was a result of literature review and pilot-testing of its preliminary versions to researchers and students. The final version of the questionnaire contains 18 items measuring the respondents’ knowledge and attitude towards generic medicines on a 5-point Likert scale. Given the ordinal nature of the data, ordinal alpha and polychoric correlations were computed. The sample was randomly split into two halves. Exploratory factor analysis, performed in the first sample, was used for the creation of multi-item scales. Confirmatory factor analysis and Generalized Linear Latent and Mixed Model analysis (GLLAMM) with the use of the rating scale model were used in the second sample to assess goodness of fit. An assessment of internal consistency reliability, test-retest reliability, and construct validity was also performed. Results Among 1402 persons contacted, 986 persons completed our questionnaire (response rate = 70.3%). Overall Cronbach’s alpha was 0.871. The conjoint use of exploratory and confirmatory factor analysis resulted in a six-scale model, which seemed to fit the data well. Five of the six scales, namely trust, drug quality, state audit, fiscal impact and drug substitution were found to be valid and reliable, while the knowledge scale suffered only from low inter-scale correlations and a ceiling effect. However, the subsequent confirmatory factor and GLLAMM analyses indicated a good fit of the model to the data. Conclusions The ATTOGEN instrument proved to be a reliable and valid tool, suitable for assessing students’ knowledge and attitudes towards generic medicines. PMID:29186163

Health anxiety and hypochondriasis in the light of DSM-5.

PubMed

Bailer, Josef; Kerstner, Tobias; Witthöft, Michael; Diener, Carsten; Mier, Daniela; Rist, Fred

2016-01-01

In the DSM-5, the diagnosis of hypochondriasis was replaced by two new diagnositic entities: somatic symptom disorder (SSD) and illness anxiety disorder (IAD). Both diagnoses share high health anxiety as a common criterion, but additonal somatic symptoms are only required for SSD but not IAD. Our aim was to provide empirical evidence for the validity of these new diagnoses using data from a case-control study of highly health-anxious (n = 96), depressed (n = 52), and healthy (n = 52) individuals. The individuals originally diagnosed as DSM-IV hypochondriasis predominantly met criteria for SSD (74%) and rarely for IAD (26%). Individuals with SSD were more impaired, had more often comorbid panic and generalized anxiety disorders, and had more medical consultations as those with IAD. Yet, no significant differences were found between SSD and IAD with regard to levels of health anxiety, other hypochondriacial characteristics, illness behavior, somatic symptom attributions, and physical concerns, whereas both groups differed significantly from clinical and healthy controls in all of these variables. These results do not support the proposed splitting of health anxiety/hypochondriasis into two diagnoses. Further validation studies with larger samples and additional control groups are warranted to prove the validity of the new diagnoses.

[Modification and evaluation of assessment of 
medication literacy].

PubMed

Zheng, Feng; Zhong, Zhuqing; Ding, Siqing; Luo, Aijing; Liu, Zina

2016-11-28

To translate and revise the Medication Literacy Assessment in English (MedLitRxSE-English) and evaluate its validity and reliability.
 Methods: We introduced MedLitRxSE-English from abroad. According to the principles of Brislin and culture adjustment, we revised it as a Chinese edition. Using random sampling method, from Oct, 2014 to Jan, 2015, 461 non-hospitalized patients from the outpatient departments of the top three hospitals in Changsha city were investigated. The reliability and validity of the scale was tested.
 Results: The test-retest reliability of the Chinese version for medication literacy scale was 0.885; the split reliability was 0.840; K-R was 0.820; the correlations between the assessment of medication literacy and the corresponding items were 0.427-0.587; the confirmatory factor analysis revealed overall good fit. Root mean square error of approximation (RMSEA), χ2/df, goodness of fit index (GFI) and comparative fit index (CFI) was 0.08, 3.06, 0.91 and 0.94, respectively. 
 Conclusion: The Chinese version for the assessment of medication literacy is in good reliability and validity, and it can be used to evaluate the medication literacy in our country.

Four reference soil and rock samples for measuring element availability in the Western Energy Regions

USGS Publications Warehouse

Crock, J.G.; Severson, R.C.

1980-01-01

Attaining acceptable precision in extractable element determinations is more difficult than in total element determinations. In total element determinations, dissolution of the sample is qualitatively checked by the clarity of the solution and the absence of residues. These criteria cannot be used for extracts. Possibilities for error are introduced in virtually every step in soil extractions. Therefore, the use of reference materials whose homogeneity and element content are reasonably well known is essential for determination of extractable elements. In this report, estimates of homogeneity and element content are presented for four reference samples. Bulk samples of about 100 kilograms of each sample were ground to pass an 80-mesh sieve. The samples were homogenized and split using a Jones-type splitter. Fourteen splits of each reference sample were analyzed for total content of Ca, Co, Cu, Fe, K, Mg, Mn, Na, and Zn; DTPA-extractable Cd, Co, Cu, Fe, Mn, Ni, Pb, and Zn; exchangeable Ca, Mg, K, and Na; cation exchange capacity water-saturation-extractable Ca, Mg, K, Na, C1, and SO4; soil pH; and hot-water-extractable boron. Error measured between splits was small, indicating that the samples were homogenized adequately and that the laboratory procedure provided reproducible results.

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

Dernotte, Jeremie; Dec, John E.; Ji, Chunsheng

A detailed understanding of the various factors affecting the trends in gross-indicated thermal efficiency with changes in key operating parameters has been carried out, applied to a one-liter displacement single-cylinder boosted Low-Temperature Gasoline Combustion (LTGC) engine. This work systematically investigates how the supplied fuel energy splits into the following four energy pathways: gross-indicated thermal efficiency, combustion inefficiency, heat transfer and exhaust losses, and how this split changes with operating conditions. Additional analysis is performed to determine the influence of variations in the ratio of specific heat capacities (γ) and the effective expansion ratio, related to the combustion-phasing retard (CA50), onmore » the energy split. Heat transfer and exhaust losses are computed using multiple standard cycle analysis techniques. Furthermore, the various methods are evaluated in order to validate the trends.« less

An implicit flux-split algorithm to calculate hypersonic flowfields in chemical equilibrium

NASA Technical Reports Server (NTRS)

Palmer, Grant

1987-01-01

An implicit, finite-difference, shock-capturing algorithm that calculates inviscid, hypersonic flows in chemical equilibrium is presented. The flux vectors and flux Jacobians are differenced using a first-order, flux-split technique. The equilibrium composition of the gas is determined by minimizing the Gibbs free energy at every node point. The code is validated by comparing results over an axisymmetric hemisphere against previously published results. The algorithm is also applied to more practical configurations. The accuracy, stability, and versatility of the algorithm have been promising.

A three-dimensional parabolic equation model of sound propagation using higher-order operator splitting and Padé approximants.

PubMed

Lin, Ying-Tsong; Collis, Jon M; Duda, Timothy F

2012-11-01

An alternating direction implicit (ADI) three-dimensional fluid parabolic equation solution method with enhanced accuracy is presented. The method uses a square-root Helmholtz operator splitting algorithm that retains cross-multiplied operator terms that have been previously neglected. With these higher-order cross terms, the valid angular range of the parabolic equation solution is improved. The method is tested for accuracy against an image solution in an idealized wedge problem. Computational efficiency improvements resulting from the ADI discretization are also discussed.

The Modified Abbreviated Math Anxiety Scale: A Valid and Reliable Instrument for Use with Children.

PubMed

Carey, Emma; Hill, Francesca; Devine, Amy; Szűcs, Dénes

2017-01-01

Mathematics anxiety (MA) can be observed in children from primary school age into the teenage years and adulthood, but many MA rating scales are only suitable for use with adults or older adolescents. We have adapted one such rating scale, the Abbreviated Math Anxiety Scale (AMAS), to be used with British children aged 8-13. In this study, we assess the scale's reliability, factor structure, and divergent validity. The modified AMAS (mAMAS) was administered to a very large ( n = 1746) cohort of British children and adolescents. This large sample size meant that as well as conducting confirmatory factor analysis on the scale itself, we were also able to split the sample to conduct exploratory and confirmatory factor analysis of items from the mAMAS alongside items from child test anxiety and general anxiety rating scales. Factor analysis of the mAMAS confirmed that it has the same underlying factor structure as the original AMAS, with subscales measuring anxiety about Learning and Evaluation in math. Furthermore, both exploratory and confirmatory factor analysis of the mAMAS alongside scales measuring test anxiety and general anxiety showed that mAMAS items cluster onto one factor (perceived to represent MA). The mAMAS provides a valid and reliable scale for measuring MA in children and adolescents, from a younger age than is possible with the original AMAS. Results from this study also suggest that MA is truly a unique construct, separate from both test anxiety and general anxiety, even in childhood.

Dental age estimation in Japanese individuals combining permanent teeth and third molars.

PubMed

Ramanan, Namratha; Thevissen, Patrick; Fleuws, Steffen; Willems, G

2012-12-01

The study aim was, firstly, to verify the Willems et al. model on a Japanese reference sample. Secondly to develop a Japanese reference model based on the Willems et al. method and to verify it. Thirdly to analyze the age prediction performance adding tooth development information of third molars to permanent teeth. Retrospectively 1877 panoramic radiographs were selected in the age range between 1 and 23 years (1248 children, 629 sub-adults). Dental development was registered applying Demirjian 's stages of the mandibular left permanent teeth in children and Köhler stages on the third molars. The children's data were, firstly, used to validate the Willems et al. model (developed a Belgian reference sample), secondly, split ino a training and a test sample. On the training sample a Japanese reference model was developed based on the Willems method. The developed model and the Willems et al; model were verified on the test sample. Regression analysis was used to detect the age prediction performance adding third molar scores to permanent tooth scores. The validated Willems et al. model provided a mean absolute error of 0.85 and 0.75 years in females and males, respectively. The mean absolute error in the verified Willems et al. and the developed Japanese reference model was 0.85, 0.77 and 0.79, 0.75 years in females and males, respectively. On average a negligible change in root mean square error values was detected adding third molar scores to permanent teeth scores. The Belgian sample could be used as a reference model to estimate the age of the Japanese individuals. Combining information from the third molars and permanent teeth was not providing clinically significant improvement of age predictions based on permanent teeth information alone.

A cooperative-binding split aptamer assay for rapid, specific and ultra-sensitive fluorescence detection of cocaine in saliva.

PubMed

Yu, Haixiang; Canoura, Juan; Guntupalli, Bhargav; Lou, Xinhui; Xiao, Yi

2017-01-01

Sensors employing split aptamers that reassemble in the presence of a target can achieve excellent specificity, but the accompanying reduction of target affinity mitigates any overall gains in sensitivity. We for the first time have developed a split aptamer that achieves enhanced target-binding affinity through cooperative binding. We have generated a split cocaine-binding aptamer that incorporates two binding domains, such that target binding at one domain greatly increases the affinity of the second domain. We experimentally demonstrate that the resulting cooperative-binding split aptamer (CBSA) exhibits higher target binding affinity and is far more responsive in terms of target-induced aptamer assembly compared to the single-domain parent split aptamer (PSA) from which it was derived. We further confirm that the target-binding affinity of our CBSA can be affected by the cooperativity of its binding domains and the intrinsic affinity of its PSA. To the best of our knowledge, CBSA-5335 has the highest cocaine affinity of any split aptamer described to date. The CBSA-based assay also demonstrates excellent performance in target detection in complex samples. Using this CBSA, we achieved specific, ultra-sensitive, one-step fluorescence detection of cocaine within fifteen minutes at concentrations as low as 50 nM in 10% saliva without signal amplification. This limit of detection meets the standards recommended by the European Union's Driving under the Influence of Drugs, Alcohol and Medicines program. Our assay also demonstrates excellent reproducibility of results, confirming that this CBSA-platform represents a robust and sensitive means for cocaine detection in actual clinical samples.

The Validity of a New Structured Assessment of Gastrointestinal Symptoms Scale (SAGIS) for Evaluating Symptoms in the Clinical Setting.

PubMed

Koloski, N A; Jones, M; Hammer, J; von Wulffen, M; Shah, A; Hoelz, H; Kutyla, M; Burger, D; Martin, N; Gurusamy, S R; Talley, N J; Holtmann, G

2017-08-01

The clinical assessments of patients with gastrointestinal symptoms can be time-consuming, and the symptoms captured during the consultation may be influenced by a variety of patient and non-patient factors. To facilitate standardized symptom assessment in the routine clinical setting, we developed the Structured Assessment of Gastrointestinal Symptom (SAGIS) instrument to precisely characterize symptoms in a routine clinical setting. We aimed to validate SAGIS including its reliability, construct and discriminant validity, and utility in the clinical setting. Development of the SAGIS consisted of initial interviews with patients referred for the diagnostic work-up of digestive symptoms and relevant complaints identified. The final instrument consisted of 22 items as well as questions on extra intestinal symptoms and was given to 1120 consecutive patients attending a gastroenterology clinic randomly split into derivation (n = 596) and validation datasets (n = 551). Discriminant validity along with test-retest reliability was assessed. The time taken to perform a clinical assessment with and without the SAGIS was recorded along with doctor satisfaction with this tool. Exploratory factor analysis conducted on the derivation sample suggested five symptom constructs labeled as abdominal pain/discomfort (seven items), gastroesophageal reflux disease/regurgitation symptoms (four items), nausea/vomiting (three items), diarrhea/incontinence (five items), and difficult defecation and constipation (2 items). Confirmatory factor analysis conducted on the validation sample supported the initially developed five-factor measurement model ([Formula: see text], p < 0.0001, χ 2 /df = 4.6, CFI = 0.90, TLI = 0.88, RMSEA = 0.08). All symptom groups demonstrated differentiation between disease groups. The SAGIS was shown to be reliable over time and resulted in a 38% reduction of the time required for clinical assessment. The SAGIS instrument has excellent psychometric properties and supports the clinical assessment of and symptom-based categorization of patients with a wide spectrum of gastrointestinal symptoms.

Evaluation of single-point sampling strategies for the estimation of moclobemide exposure in depressive patients.

PubMed

Ignjatovic, Anita Rakic; Miljkovic, Branislava; Todorovic, Dejan; Timotijevic, Ivana; Pokrajac, Milena

2011-05-01

Because moclobemide pharmacokinetics vary considerably among individuals, monitoring of plasma concentrations lends insight into its pharmacokinetic behavior and enhances its rational use in clinical practice. The aim of this study was to evaluate whether single concentration-time points could adequately predict moclobemide systemic exposure. Pharmacokinetic data (full 7-point pharmacokinetic profiles), obtained from 21 depressive inpatients receiving moclobemide (150 mg 3 times daily), were randomly split into development (n = 18) and validation (n = 16) sets. Correlations between the single concentration-time points and the area under the concentration-time curve within a 6-hour dosing interval at steady-state (AUC(0-6)) were assessed by linear regression analyses. The predictive performance of single-point sampling strategies was evaluated in the validation set by mean prediction error, mean absolute error, and root mean square error. Plasma concentrations in the absorption phase yielded unsatisfactory predictions of moclobemide AUC(0-6). The best estimation of AUC(0-6) was achieved from concentrations at 4 and 6 hours following dosing. As the most reliable surrogate for moclobemide systemic exposure, concentrations at 4 and 6 hours should be used instead of predose trough concentrations as an indicator of between-patient variability and a guide for dose adjustments in specific clinical situations.

Development and validation of the brief esophageal dysphagia questionnaire.

PubMed

Taft, T H; Riehl, M; Sodikoff, J B; Kahrilas, P J; Keefer, L; Doerfler, B; Pandolfino, J E

2016-12-01

Esophageal dysphagia is common in gastroenterology practice and has multiple etiologies. A complication for some patients with dysphagia is food impaction. A valid and reliable questionnaire to rapidly evaluate esophageal dysphagia and impaction symptoms can aid the gastroenterologist in gathering information to inform treatment approach and further evaluation, including endoscopy. 1638 patients participated over two study phases. 744 participants completed the Brief Esophageal Dysphagia Questionnaire (BEDQ) for phase 1; 869 completed the BEDQ, Visceral Sensitivity Index, Gastroesophageal Reflux Disease Questionnaire, and Hospital Anxiety and Depression Scale for phase 2. Demographic and clinical data were obtained via the electronic medical record. The BEDQ was evaluated for internal consistency, split-half reliability, ceiling and floor effects, and construct validity. The BEDQ demonstrated excellent internal consistency, reliability, and construct validity. The symptom frequency and severity scales scored above the standard acceptable cutoffs for reliability while the impaction subscale yielded poor internal consistency and split-half reliability; thus the impaction items were deemed qualifiers only and removed from the total score. No significant ceiling or floor effects were found with the exception of 1 item, and inter-item correlations fell within accepted ranges. Construct validity was supported by moderate yet significant correlations with other measures. The predictive ability of the BEDQ was small but significant. The BEDQ represents a rapid, reliable, and valid assessment tool for esophageal dysphagia with food impaction for clinical practice that differentiates between patients with major motor dysfunction and mechanical obstruction. © 2016 John Wiley & Sons Ltd.

Development and Validation of the Brief Esophageal Dysphagia Questionnaire

PubMed Central

Taft, Tiffany H.; Riehl, Megan; Sodikoff, Jamie B.; Kahrilas, Peter J.; Keefer, Laurie; Doerfler, Bethany; Pandolfino, John E.

2017-01-01

Background Esophageal dysphagia is common in gastroenterology practice and has multiple etiologies. A complication for some patients with dysphagia is food impaction. A valid and reliable questionnaire to rapidly evaluate esophageal dysphagia and impaction symptoms can aid the gastroenterologist in gathering information to inform treatment approach and further evaluation, including endoscopy. Methods 1,638 patients participated over two study phases. 744 participants completed the Brief Esophageal Dysphagia Questionnaire (BEDQ) for phase 1; 869 completed the BEDQ, Visceral Sensitivity Index, Gastroesophageal Reflux Disease Questionnaire, and Hospital Anxiety and Depression Scale for phase 2. Demographic and clinical data were obtained via the electronic medical record. The BEDQ was evaluated for internal consistency, split-half reliability, ceiling and floor effects, and construct validity. Key Results The BEDQ demonstrated excellent internal consistency, reliability, and construct validity. The symptom frequency and severity scales scored above the standard acceptable cutoffs for reliability while the impaction subscale yielded poor internal consistency and split-half reliability; thus the impaction items were deemed qualifiers only and removed from the total score. No significant ceiling or floor effects were found with the exception of 1 item, and inter-item correlations fell within accepted ranges. Construct validity was supported by moderate yet significant correlations with other measures. The predictive ability of the BEDQ was small but significant. Conclusions & Inferences The BEDQ represents a rapid, reliable and valid assessment tool for esophageal dysphagia with food impaction for clinical practice that differentiates between patients with major motor dysfunction and mechanical obstruction. PMID:27380834

[Reliability and Validity of the Korean Version of the Perinatal Post-Traumatic Stress Disorder Questionnaire].

PubMed

Park, Yu Kyung; Ju, Hyeon Ok; Na, Hunjoo

2016-02-01

The Perinatal Post-Traumatic Stress Disorder Questionnaire (PPQ) was designed to measure post-traumatic symptoms related to childbirth and symptoms during postnatal period. The purpose of this study was to develop a translated Korean version of the PPQ and to evaluate reliability and validity of the Korean PPQ. Participants were 196 mothers at one to 18 months after giving childbirth and data were collected through e-mails. The PPQ was translated into Korean using translation guideline from World Health Organization. For this study Cronbach's alpha and split-half reliability were used to evaluate the reliability of the PPQ. Exploratory Factor Analysis (EFA), Confirmatory Factor Analysis (CFA), and known-group validity were conducted to examine construct validity. Correlations of the PPQ with Impact of Event Scale (IES), Beck Depression Inventory II (BDI-II), and Beck Anxiety Inventory (BAI) were used to test a criterion validity of the PPQ. Cronbach's alpha and Spearman-Brown split-half correlation coefficient were 0.91 and 0.77, respectively. EFA identified a 3-factor solution including arousal, avoidance, and intrusion factors and CFA revealed the strongest support for the 3-factor model. The correlations of the PPQ with IES, BDI-II, and BAI were .99, .60, and .72, respectively, pointing to criterion validity of a high level. The Korean version PPQ is a useful tool for screening and assessing mothers' experiencing emotional distress related to child birth and during the postnatal period. The PPQ also reflects Post Traumatic Stress Disorder's diagnostic standards well.

Body fat measurement by bioelectrical impedance and air displacement plethysmography: a cross-validation study to design bioelectrical impedance equations in Mexican adults

PubMed Central

Macias, Nayeli; Alemán-Mateo, Heliodoro; Esparza-Romero, Julián; Valencia, Mauro E

2007-01-01

Background The study of body composition in specific populations by techniques such as bio-impedance analysis (BIA) requires validation based on standard reference methods. The aim of this study was to develop and cross-validate a predictive equation for bioelectrical impedance using air displacement plethysmography (ADP) as standard method to measure body composition in Mexican adult men and women. Methods This study included 155 male and female subjects from northern Mexico, 20–50 years of age, from low, middle, and upper income levels. Body composition was measured by ADP. Body weight (BW, kg) and height (Ht, cm) were obtained by standard anthropometric techniques. Resistance, R (ohms) and reactance, Xc (ohms) were also measured. A random-split method was used to obtain two samples: one was used to derive the equation by the "all possible regressions" procedure and was cross-validated in the other sample to test predicted versus measured values of fat-free mass (FFM). Results and Discussion The final model was: FFM (kg) = 0.7374 * (Ht2 /R) + 0.1763 * (BW) - 0.1773 * (Age) + 0.1198 * (Xc) - 2.4658. R2 was 0.97; the square root of the mean square error (SRMSE) was 1.99 kg, and the pure error (PE) was 2.96. There was no difference between FFM predicted by the new equation (48.57 ± 10.9 kg) and that measured by ADP (48.43 ± 11.3 kg). The new equation did not differ from the line of identity, had a high R2 and a low SRMSE, and showed no significant bias (0.87 ± 2.84 kg). Conclusion The new bioelectrical impedance equation based on the two-compartment model (2C) was accurate, precise, and free of bias. This equation can be used to assess body composition and nutritional status in populations similar in anthropometric and physical characteristics to this sample. PMID:17697388

English Validation of the Parental Socialization Scale—ESPA29

PubMed Central

Martínez, Isabel; Cruise, Edie; García, Óscar F.; Murgui, Sergio

2017-01-01

Parenting styles have traditionally been studied following the classical two-dimensional orthogonal model of parental socialization. The Parental Socialization Scale ESPA29 is used to measure the four styles of parental socialization through the acceptance/involvement and strictness/imposition dimensions. The ESPA29 scale is a developmentally appropriate measure of parenting styles, which has been validated in several languages including Spanish, Italian, and Brazilian Portuguese. In this study, the English translation of the ESPA29 was evaluated. The objective of the work is to test the ESPA29’s structure of parenting practices with a United States sample measuring parenting practices using exploratory factor analysis (EFA) and confirmatory factor analysis (CFA). The scores of fathers’ and mothers’ behavioral practices toward their children were obtained for a sample of 911 United States adolescents between 14 and 18 years of age. First, the total sample was split and a principal components analysis with varimax rotation was carried out with one of the two halves. EFA showed a two-factor structure fully congruent with the theoretical model for mothers’ and fathers’ scores. Next, a CFA was calculated on the second half by using the factor structure obtained in the previous EFA. The CFA replicated the two-factor structure with appropriate fit index. The seven parenting practices that were measured loaded appropriately on the acceptance/involvement and strictness/imposition dimensions. Then, the multigroup analysis between girls and boys showed equal loading in the factors and equal covariation between the acceptance/involvement and the strictness/imposition dimensions. Additionally, the two dimensions of the ESPA29 scale were related to self-esteem in order to obtain an external validity index. The findings confirm the invariant structure of the ESPA29 was in the United States and their equivalence in both fathers’ and mothers’ scores. These findings validate the instrument and confirm its applicability in cross-cultural research on parenting practices and child adjustment. PMID:28611711

English Validation of the Parental Socialization Scale-ESPA29.

PubMed

Martínez, Isabel; Cruise, Edie; García, Óscar F; Murgui, Sergio

2017-01-01

Parenting styles have traditionally been studied following the classical two-dimensional orthogonal model of parental socialization. The Parental Socialization Scale ESPA29 is used to measure the four styles of parental socialization through the acceptance/involvement and strictness/imposition dimensions. The ESPA29 scale is a developmentally appropriate measure of parenting styles, which has been validated in several languages including Spanish, Italian, and Brazilian Portuguese. In this study, the English translation of the ESPA29 was evaluated. The objective of the work is to test the ESPA29's structure of parenting practices with a United States sample measuring parenting practices using exploratory factor analysis (EFA) and confirmatory factor analysis (CFA). The scores of fathers' and mothers' behavioral practices toward their children were obtained for a sample of 911 United States adolescents between 14 and 18 years of age. First, the total sample was split and a principal components analysis with varimax rotation was carried out with one of the two halves. EFA showed a two-factor structure fully congruent with the theoretical model for mothers' and fathers' scores. Next, a CFA was calculated on the second half by using the factor structure obtained in the previous EFA. The CFA replicated the two-factor structure with appropriate fit index. The seven parenting practices that were measured loaded appropriately on the acceptance/involvement and strictness/imposition dimensions. Then, the multigroup analysis between girls and boys showed equal loading in the factors and equal covariation between the acceptance/involvement and the strictness/imposition dimensions. Additionally, the two dimensions of the ESPA29 scale were related to self-esteem in order to obtain an external validity index. The findings confirm the invariant structure of the ESPA29 was in the United States and their equivalence in both fathers' and mothers' scores. These findings validate the instrument and confirm its applicability in cross-cultural research on parenting practices and child adjustment.

Predicting long-term survival after coronary artery bypass graft surgery.

PubMed

Karim, Md N; Reid, Christopher M; Huq, Molla; Brilleman, Samuel L; Cochrane, Andrew; Tran, Lavinia; Billah, Baki

2018-02-01

To develop a model for predicting long-term survival following coronary artery bypass graft surgery. This study included 46 573 patients from the Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZCTS) registry, who underwent isolated coronary artery bypass graft surgery between 2001 and 2014. Data were randomly split into development (23 282) and validation (23 291) samples. Cox regression models were fitted separately, using the important preoperative variables, for 4 'time intervals' (31-90 days, 91-365 days, 1-3 years and >3 years), with optimal predictors selected using the bootstrap bagging technique. Model performance was assessed both in validation data and in combined data (development and validation samples). Coefficients of all 4 final models were estimated on the combined data adjusting for hospital-level clustering. The Kaplan-Meier mortality rates estimated in the sample were 1.7% at 90 days, 2.8% at 1 year, 4.4% at 2 years and 6.1% at 3 years. Age, peripheral vascular disease, respiratory disease, reduced ejection fraction, renal dysfunction, arrhythmia, diabetes, hypercholesterolaemia, cerebrovascular disease, hypertension, congestive heart failure, steroid use and smoking were included in all 4 models. However, their magnitude of effect varied across the time intervals. Harrell's C-statistics was 0.83, 0.78, 0.75 and 0.74 for 31-90 days, 91-365 days, 1-3 years and >3 years models, respectively. Models showed excellent discrimination and calibration in validation data. Models were developed for predicting long-term survival at 4 time intervals after isolated coronary artery bypass graft surgery. These models can be used in conjunction with the existing 30-day mortality prediction model. © The Author 2017. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

Node-Splitting Generalized Linear Mixed Models for Evaluation of Inconsistency in Network Meta-Analysis.

PubMed

Yu-Kang, Tu

2016-12-01

Network meta-analysis for multiple treatment comparisons has been a major development in evidence synthesis methodology. The validity of a network meta-analysis, however, can be threatened by inconsistency in evidence within the network. One particular issue of inconsistency is how to directly evaluate the inconsistency between direct and indirect evidence with regard to the effects difference between two treatments. A Bayesian node-splitting model was first proposed and a similar frequentist side-splitting model has been put forward recently. Yet, assigning the inconsistency parameter to one or the other of the two treatments or splitting the parameter symmetrically between the two treatments can yield different results when multi-arm trials are involved in the evaluation. We aimed to show that a side-splitting model can be viewed as a special case of design-by-treatment interaction model, and different parameterizations correspond to different design-by-treatment interactions. We demonstrated how to evaluate the side-splitting model using the arm-based generalized linear mixed model, and an example data set was used to compare results from the arm-based models with those from the contrast-based models. The three parameterizations of side-splitting make slightly different assumptions: the symmetrical method assumes that both treatments in a treatment contrast contribute to inconsistency between direct and indirect evidence, whereas the other two parameterizations assume that only one of the two treatments contributes to this inconsistency. With this understanding in mind, meta-analysts can then make a choice about how to implement the side-splitting method for their analysis. Copyright © 2016 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

Prediction Models for 30-Day Mortality and Complications After Total Knee and Hip Arthroplasties for Veteran Health Administration Patients With Osteoarthritis.

PubMed

Harris, Alex Hs; Kuo, Alfred C; Bowe, Thomas; Gupta, Shalini; Nordin, David; Giori, Nicholas J

2018-05-01

Statistical models to preoperatively predict patients' risk of death and major complications after total joint arthroplasty (TJA) could improve the quality of preoperative management and informed consent. Although risk models for TJA exist, they have limitations including poor transparency and/or unknown or poor performance. Thus, it is currently impossible to know how well currently available models predict short-term complications after TJA, or if newly developed models are more accurate. We sought to develop and conduct cross-validation of predictive risk models, and report details and performance metrics as benchmarks. Over 90 preoperative variables were used as candidate predictors of death and major complications within 30 days for Veterans Health Administration patients with osteoarthritis who underwent TJA. Data were split into 3 samples-for selection of model tuning parameters, model development, and cross-validation. C-indexes (discrimination) and calibration plots were produced. A total of 70,569 patients diagnosed with osteoarthritis who received primary TJA were included. C-statistics and bootstrapped confidence intervals for the cross-validation of the boosted regression models were highest for cardiac complications (0.75; 0.71-0.79) and 30-day mortality (0.73; 0.66-0.79) and lowest for deep vein thrombosis (0.59; 0.55-0.64) and return to the operating room (0.60; 0.57-0.63). Moderately accurate predictive models of 30-day mortality and cardiac complications after TJA in Veterans Health Administration patients were developed and internally cross-validated. By reporting model coefficients and performance metrics, other model developers can test these models on new samples and have a procedure and indication-specific benchmark to surpass. Published by Elsevier Inc.

The Moral Injury Symptom Scale-Military Version.

PubMed

Koenig, Harold G; Ames, Donna; Youssef, Nagy A; Oliver, John P; Volk, Fred; Teng, Ellen J; Haynes, Kerry; Erickson, Zachary D; Arnold, Irina; O'Garo, Keisha; Pearce, Michelle

2018-02-01

The purpose of this study was to develop a multi-dimensional measure of moral injury symptoms that can be used as a primary outcome measure in intervention studies that target moral injury (MI) in Veterans and Active Duty Military with PTSD. This was a multi-center study of 427 Veterans and Active Duty Military with PTSD symptoms recruited from VA Medical Centers in Augusta, Los Angeles, Durham, Houston, and San Antonio, and from Liberty University in Lynchburg. Internal reliability of the Moral Injury Symptom Scale-Military Version (MISS-M) was examined along with factor analytic, discriminant, and convergent validity. Participants were randomly split into two equal samples, with exploratory factor analysis conducted in the first sample and confirmatory factor analysis in the second. Test-retest reliability was assessed in a subsample of 64 Veterans. The 45-item MISS-M consists of 10 theoretically grounded subscales assessing guilt, shame, moral concerns, religious struggles, loss of religious faith/hope, loss of meaning/purpose, difficulty forgiving, loss of trust, and self-condemnation. The Cronbach's alpha of the overall scale was .92 and of individual subscales ranged from .56 to .91. The test-retest reliability was .91 for the total scale and ranged from .78 to .90 for subscales. Discriminant validity was demonstrated by relatively weak correlations with other psychosocial, religious, and physical health constructs, and convergent validity was indicated by strong correlations with PTSD, depression, and anxiety symptoms. The MISS-M is a reliable and valid multi-dimensional symptom measure of moral injury that can be used in studies targeting MI in Veterans and Active Duty Military with PTSD symptoms and may also be used by clinicians to identify those at risk.

Comparative genomics approach to detecting split-coding regions in a low-coverage genome: lessons from the chimaera Callorhinchus milii (Holocephali, Chondrichthyes).

PubMed

Dessimoz, Christophe; Zoller, Stefan; Manousaki, Tereza; Qiu, Huan; Meyer, Axel; Kuraku, Shigehiro

2011-09-01

Recent development of deep sequencing technologies has facilitated de novo genome sequencing projects, now conducted even by individual laboratories. However, this will yield more and more genome sequences that are not well assembled, and will hinder thorough annotation when no closely related reference genome is available. One of the challenging issues is the identification of protein-coding sequences split into multiple unassembled genomic segments, which can confound orthology assignment and various laboratory experiments requiring the identification of individual genes. In this study, using the genome of a cartilaginous fish, Callorhinchus milii, as test case, we performed gene prediction using a model specifically trained for this genome. We implemented an algorithm, designated ESPRIT, to identify possible linkages between multiple protein-coding portions derived from a single genomic locus split into multiple unassembled genomic segments. We developed a validation framework based on an artificially fragmented human genome, improvements between early and recent mouse genome assemblies, comparison with experimentally validated sequences from GenBank, and phylogenetic analyses. Our strategy provided insights into practical solutions for efficient annotation of only partially sequenced (low-coverage) genomes. To our knowledge, our study is the first formulation of a method to link unassembled genomic segments based on proteomes of relatively distantly related species as references.

Comparative genomics approach to detecting split-coding regions in a low-coverage genome: lessons from the chimaera Callorhinchus milii (Holocephali, Chondrichthyes)

PubMed Central

Zoller, Stefan; Manousaki, Tereza; Qiu, Huan; Meyer, Axel; Kuraku, Shigehiro

2011-01-01

Recent development of deep sequencing technologies has facilitated de novo genome sequencing projects, now conducted even by individual laboratories. However, this will yield more and more genome sequences that are not well assembled, and will hinder thorough annotation when no closely related reference genome is available. One of the challenging issues is the identification of protein-coding sequences split into multiple unassembled genomic segments, which can confound orthology assignment and various laboratory experiments requiring the identification of individual genes. In this study, using the genome of a cartilaginous fish, Callorhinchus milii, as test case, we performed gene prediction using a model specifically trained for this genome. We implemented an algorithm, designated ESPRIT, to identify possible linkages between multiple protein-coding portions derived from a single genomic locus split into multiple unassembled genomic segments. We developed a validation framework based on an artificially fragmented human genome, improvements between early and recent mouse genome assemblies, comparison with experimentally validated sequences from GenBank, and phylogenetic analyses. Our strategy provided insights into practical solutions for efficient annotation of only partially sequenced (low-coverage) genomes. To our knowledge, our study is the first formulation of a method to link unassembled genomic segments based on proteomes of relatively distantly related species as references. PMID:21712341

[Testing reliability and validity of reduced substitutes for leadership scales(rd-SLS)].

PubMed

Kim, Jeong-Hee

2005-10-01

This paper was conducted to test the reliability and validity of rd-SLS, developed by Podsakoff, et al. (1993) which measured 'substitutes for leadership'. The subjects were 345 nurses in 5 general hospitals. Cronbach's and the Guttman split-half coefficient were used to test the reliability of rd-SLS. Factor analysis, and the correlations of the rv-SLS and SLS with rd-SLS were used for convergent and discriminant validity. Cronbach's data was 0.76 and the Guttman split-half coefficient was 0.52. Twelve factors evolved by factor analysis, which explained 70.4% of the total variance. This result was similar to previous study results. However, 'Indifference toward organizational rewards'-related items were classified two factors. It was not clear t hat the rd-SLS consisted of 13 concepts(factors). The correlations of the rv-SLS and SLS with the rd-SLS were 0.93 and 0.87 respectively. The rd-SLS showed a moderate degree of validity and reliability. Thus, it is recommended to use the rd-SLS in general nursing organizations for screening for leadership substitutes. In addition, it is necessary to clarify the concept of organizational rewards. In a further study, the factor structure of the rd-SLS may be considered.

Evaluating diagnosis-based case-mix measures: how well do they apply to the VA population?

PubMed

Rosen, A K; Loveland, S; Anderson, J J; Rothendler, J A; Hankin, C S; Rakovski, C C; Moskowitz, M A; Berlowitz, D R

2001-07-01

Diagnosis-based case-mix measures are increasingly used for provider profiling, resource allocation, and capitation rate setting. Measures developed in one setting may not adequately capture the disease burden in other settings. To examine the feasibility of adapting two such measures, Adjusted Clinical Groups (ACGs) and Diagnostic Cost Groups (DCGs), to the Department of Veterans Affairs (VA) population. A 60% random sample of veterans who used health care services during FY 1997 was obtained from VA inpatient and outpatient administrative databases. A split-sample technique was used to obtain a 40% sample (n = 1,046,803) for development and a 20% sample (n = 524,461) for validation. Concurrent ACG and DCG risk adjustment models, using 1997 diagnoses and demographics to predict FY 1997 utilization (ambulatory provider encounters, and service days-the sum of a patient's inpatient and outpatient visit days), were fitted and cross-validated. Patients were classified into groupings that indicated a population with multiple psychiatric and medical diseases. Model R-squares explained between 6% and 32% of the variation in service utilization. Although reparameterized models did better in predicting utilization than models with external weights, none of the models was adequate in characterizing the entire population. For predicting service days, DCGs were superior to ACGs in most categories, whereas ACGs did better at discriminating among veterans who had the lowest utilization. Although "off-the-shelf" case-mix measures perform moderately well when applied to another setting, modifications may be required to accurately characterize a population's disease burden with respect to the resource needs of all patients.

Detection of membrane protein-protein interaction in planta based on dual-intein-coupled tripartite split-GFP association.

PubMed

Liu, Tzu-Yin; Chou, Wen-Chun; Chen, Wei-Yuan; Chu, Ching-Yi; Dai, Chen-Yi; Wu, Pei-Yu

2018-05-01

Despite the great interest in identifying protein-protein interactions (PPIs) in biological systems, only a few attempts have been made at large-scale PPI screening in planta. Unlike biochemical assays, bimolecular fluorescence complementation allows visualization of transient and weak PPIs in vivo at subcellular resolution. However, when the non-fluorescent fragments are highly expressed, spontaneous and irreversible self-assembly of the split halves can easily generate false positives. The recently developed tripartite split-GFP system was shown to be a reliable PPI reporter in mammalian and yeast cells. In this study, we adapted this methodology, in combination with the β-estradiol-inducible expression cassette, for the detection of membrane PPIs in planta. Using a transient expression assay by agroinfiltration of Nicotiana benthamiana leaves, we demonstrate the utility of the tripartite split-GFP association in plant cells and affirm that the tripartite split-GFP system yields no spurious background signal even with abundant fusion proteins readily accessible to the compartments of interaction. By validating a few of the Arabidopsis PPIs, including the membrane PPIs implicated in phosphate homeostasis, we proved the fidelity of this assay for detection of PPIs in various cellular compartments in planta. Moreover, the technique combining the tripartite split-GFP association and dual-intein-mediated cleavage of polyprotein precursor is feasible in stably transformed Arabidopsis plants. Our results provide a proof-of-concept implementation of the tripartite split-GFP system as a potential tool for membrane PPI screens in planta. © 2018 The Authors The Plant Journal © 2018 John Wiley & Sons Ltd.

Evaluation of selected information on splitting devices for water samples

USGS Publications Warehouse

Capel, P.D.; Larson, S.J.

1996-01-01

Four devices for splitting water samples into representative aliquots are used by the U.S. Geological Survey's Water Resources Division. A thorough evaluation of these devices (14-liter churn, 8-liter churn, plastic cone, and Teflon cone) encompasses a wide variety of concerns, based on both chemical and physical considerations. This report surveys the existing data (as of April 1994) on cleaning efficiency and splitting capability of these devices and presents the data in a systematic framework for evaluation. From the existing data, some of these concerns are adequately or partially addressed, but the majority of concerns could not be addressed because of the lack of data. In general, the existing cleaning and transport protocols are adequate at the milligram per liter level, but the adequacy is largely unknown for trace elements and organic chemicals at lower concen- trations. The existing data indicate that better results are obtained when the splitters are cleaned in the laboratory rather than in the field. Two conclusions that can be reached on the splitting capability of solids are that more work must be done with all four devices to characterize and quantify their limitations and range of usefulness, and that the 14-liter churn (and by association, the 8-liter churn) is not useful in obtaining representative splits of sand-sized particles.

Psychometric properties of the Thought-Action Fusion Scale in a Turkish sample.

PubMed

Yorulmaz, Orçun; Yilmaz, A Esin; Gençöz, Tülin

2004-10-01

The aim of the present study was to reveal the cross-cultural utility of the Thought-Action Fusion Scale (TAFS; J. Anxiety Disord. 10 (1996) 379). Thought-action fusion (TAF) refers to the tendency to overvalue the significance and the consequences of thoughts. Two hundred and fifty one undergraduate Turkish students participated in the current study. The reliability and validity analyses of the Turkish version of the scale indicated that the TAFS had adequate psychometric properties in a Turkish sample. Consistent with the original TAF, the Turkish version of TAFS revealed two subscales as TAF-Likelihood and TAF-Morality. Reliability analysis showed that TAF Scale and its factors had adequate internal consistencies and split-half reliability coefficients. Confirming the expectations, TAFS scores were found to be significantly and positively correlated with obsessive-compulsive symptoms, responsibility, and guilt measures. Moreover, it was found that people with high obsessive-compulsive symptoms had higher TAFS scores than those with low symptoms.

Psychometric properties of the Adolescent Dissociative Experiences Scale in a sample of Italian adolescents.

PubMed

Schimmenti, Adriano

2016-01-01

The purpose of this study was to examine the psychometric properties of the Italian translation of the Adolescent Dissociative Experiences Scale (A-DES). A sample of 1,806 high-school students between the ages of 13 and 18 years, recruited in 6 Italian cities, completed the A-DES. The A-DES showed high internal consistency, excellent item-to-scale homogeneity, good split-half reliability, and a single-factor structure. The scores of the Italian adolescents were comparable to those found in previous research with the measure. No gender differences were found in mean A-DES scores, but boys and girls showed different patterns of responses on A-DES items. Age differences were also found, with 13- and 18-year-old students scoring higher on the measure than the other participants. A cluster analysis showed that participants could be consistently grouped into 2 clusters of low- and high-dissociative adolescents. This study supports the A-DES as a reliable and valid screening measure for dissociative symptoms in adolescents.

Validation of the Japanese version of the job crafting scale.

PubMed

Eguchi, Hisashi; Shimazu, Akihito; Bakker, Arnold B; Tims, Maria; Kamiyama, Kimika; Hara, Yujiro; Namba, Katsuyuki; Inoue, Akiomi; Ono, Masakatsu; Kawakami, Norito

2016-06-16

The aim of this study was to validate the Japanese version of the job crafting scale (JCS-J). JCS measures four independent job crafting dimensions, namely increasing structural job resources, decreasing hindering job demands, increasing social job resources, and increasing challenging job demands. The translated and back-translated JCS-J questionnaires were administered online to 972 employees of a Japanese manufacturing company. The data were then divided into independent explorative and confirmative samples. Exploratory and confirmatory factor analyses were performed to evaluate the factorial validity of JCS-J. The relationship with potential consequences of job crafting (e.g., job demands, job resources, and psychological well-being) was investigated to evaluate construct validity. Internal consistency was examined to evaluate the reliability of the four JCSs. An exploratory factor analysis extracted a five-factor solution. Decreasing hindering job demands was further split into two separate dimensions supporting a five- rather than four-factor structure. A series of confirmatory factor analyses revealed that the modified five-factor model that allows covariance between items fits the data best. Construct validity was generally supported by the expected correlations of each job crafting dimension with each corresponding job resource (+), job demand (+), and psychological well-being (+). Cronbach's α coefficient was sufficient for each of the four dimensions of job crafting (α ranged between 0.76 and 0.90). This study confirmed that JCS-J is an adequate measure of job crafting that can be used in the Japanese context.

Validation of the Japanese version of the job crafting scale

PubMed Central

Eguchi, Hisashi; Shimazu, Akihito; Bakker, Arnold B.; Tims, Maria; Kamiyama, Kimika; Hara, Yujiro; Namba, Katsuyuki; Inoue, Akiomi; Ono, Masakatsu; Kawakami, Norito

2016-01-01

Objectives: The aim of this study was to validate the Japanese version of the job crafting scale (JCS-J). JCS measures four independent job crafting dimensions, namely increasing structural job resources, decreasing hindering job demands, increasing social job resources, and increasing challenging job demands. Methods: The translated and back-translated JCS-J questionnaires were administered online to 972 employees of a Japanese manufacturing company. The data were then divided into independent explorative and confirmative samples. Exploratory and confirmatory factor analyses were performed to evaluate the factorial validity of JCS-J. The relationship with potential consequences of job crafting (e.g., job demands, job resources, and psychological well-being) was investigated to evaluate construct validity. Internal consistency was examined to evaluate the reliability of the four JCSs. Results: An exploratory factor analysis extracted a five-factor solution. Decreasing hindering job demands was further split into two separate dimensions supporting a five- rather than four-factor structure. A series of confirmatory factor analyses revealed that the modified five-factor model that allows covariance between items fits the data best. Construct validity was generally supported by the expected correlations of each job crafting dimension with each corresponding job resource (+), job demand (+), and psychological well-being (+). Cronbach's α coefficient was sufficient for each of the four dimensions of job crafting (α ranged between 0.76 and 0.90). Conclusions: This study confirmed that JCS-J is an adequate measure of job crafting that can be used in the Japanese context. PMID:27108643

The effect of SEM imaging on the Ar/Ar system in feldspars

NASA Astrophysics Data System (ADS)

Flude, S.; Sherlock, S.; Lee, M.; Kelley, S. P.

2010-12-01

Complex microtextures form in K-feldspar crystals as they cool and are affected by deuteric alteration. This complex structure is the cause of variable closure temperatures for Ar-Ar, a phenomenon which has been utilized in multi domain diffusion (MDD) modelling to recover thermal histories [1]. However, there has been substantial controversy regarding the precise interaction between feldspar microtextures and Ar-diffusion [2,3]. A number of studies have addressed this issue using coupled SEM imaging and Ar/Ar UV laser ablation microprobe (UV-LAMP) analysis on the same sample, to enable direct comparison of microtextures with Ar/Ar age data [4]. Here we have tested the idea that SEM work may affect Ar/Ar ages, leading to inaccurate results in subsequent Ar/Ar analyses. Three splits of alkali feldspar from the Dartmoor Granite in SW England were selected for Ar/Ar UV-LAMP analysis. Split 1 (“control”) was prepared as a polished thick section for Ar/Ar analysis. Split 2 (“SEM”) was prepared as a polished thick section, was chemically-mechanically polished with colloidal silica and underwent SEM imaging (uncoated) and focussed ion beam (FIB) milling (gold coated); electron beam damage in the SEM was maximised by leaving the sample at high magnification for eight minutes. Split 3 (“Etch”) is a cleavage fragment that was etched with HF vapour and underwent low to moderate magnification SEM imaging. The control split gave a range of laser-spot ages consistent with the expected cooling age of the granite and high yields of radiogenic 40Ar* (>90%). The area of the “SEM” split that experienced significant electron beam damage gave younger than expected ages and 40Ar* yields as low as 57%. These are interpreted as a combination of implantation of atmospheric Ar and local redistribution of K within the sample. The area of “SEM” that underwent FIB milling gave ages and 40Ar* yields comparable to the control split, suggesting that the Au-coat minimises FIB damage and that colloidal-polishing and low-magnification SEM imaging do not affect the Ar/Ar system. The “Etch” split gave younger than expected ages and 40Ar* yields as low as 58%, suggesting that HF etching also disrupts the Ar/Ar system. These results suggest that SEM techniques involving intense electron bombardment of an uncoated sample, such as charge contrast imaging and electron backscatter diffraction (EBSD), may disrupt the Ar/Ar system in the sample, leading to spurious results. Etching samples with HF, as is often done for routine Ar/Ar preparation of volcanic phenocrysts, introduces atmospheric Ar and may result in differential loss or gain of K and Ar isotopes, leading to spurious results. References [1] Lovera and Richter, 1989, J. Geophys. Res. 94, 17917-17935. [2] Parsons. et al., 1999, Cont. Min. Pet. 136, 92-110. [3] Mark et al., 2008, Geochim. Cosmochim. Acta, 72 2695-2710. [4] Reddy et al., 2001, Cont. Min. Pet., 141 186-200.

Iterative random vs. Kennard-Stone sampling for IR spectrum-based classification task using PLS2-DA

NASA Astrophysics Data System (ADS)

Lee, Loong Chuen; Liong, Choong-Yeun; Jemain, Abdul Aziz

2018-04-01

External testing (ET) is preferred over auto-prediction (AP) or k-fold-cross-validation in estimating more realistic predictive ability of a statistical model. With IR spectra, Kennard-stone (KS) sampling algorithm is often used to split the data into training and test sets, i.e. respectively for model construction and for model testing. On the other hand, iterative random sampling (IRS) has not been the favored choice though it is theoretically more likely to produce reliable estimation. The aim of this preliminary work is to compare performances of KS and IRS in sampling a representative training set from an attenuated total reflectance - Fourier transform infrared spectral dataset (of four varieties of blue gel pen inks) for PLS2-DA modeling. The `best' performance achievable from the dataset is estimated with AP on the full dataset (APF, error). Both IRS (n = 200) and KS were used to split the dataset in the ratio of 7:3. The classic decision rule (i.e. maximum value-based) is employed for new sample prediction via partial least squares - discriminant analysis (PLS2-DA). Error rate of each model was estimated repeatedly via: (a) AP on full data (APF, error); (b) AP on training set (APS, error); and (c) ET on the respective test set (ETS, error). A good PLS2-DA model is expected to produce APS, error and EVS, error that is similar to the APF, error. Bearing that in mind, the similarities between (a) APS, error vs. APF, error; (b) ETS, error vs. APF, error and; (c) APS, error vs. ETS, error were evaluated using correlation tests (i.e. Pearson and Spearman's rank test), using series of PLS2-DA models computed from KS-set and IRS-set, respectively. Overall, models constructed from IRS-set exhibits more similarities between the internal and external error rates than the respective KS-set, i.e. less risk of overfitting. In conclusion, IRS is more reliable than KS in sampling representative training set.

Tablet splitting: is it worthwhile? Analysis of drug content and weight uniformity for half tablets of 16 commonly used medications in the outpatient setting.

PubMed

Helmy, Sally A

2015-01-01

Tablet splitting is a well-established medical practice in clinical settings for multiple reasons, including cost savings and ease of swallowing. However, it does not necessarily result in weight-uniform half tablets. To (a) investigate the effect of tablet characteristics on weight and content uniformity of half tablets, resulting from splitting 16 commonly used medications in the outpatient setting and (b) provide recommendations for safe tablet-splitting prescribing practices. Ten random tablets from each of the selected medications were weighed and split by 5 volunteers (2 men and 3 women aged 25-44 years) using a knife. The selected medications were mirtazapine 30 mg, bromazepam 3 mg, oxcarbazepin 150 mg, sertraline 50 mg, carvedilol 25 mg, bisoprolol fumarate 10 mg, losartan 50 mg, digoxin 0.25 mg, amiodarone HCl 200 mg, metformin HCl 1,000 mg, glimepiride 4 mg, montelukast 10 mg, ibuprofen 600 mg, celecoxib 200 mg, meloxicam 15 mg, and sildenafil citrate 50 mg. The resulting half tablets were evaluated for weight and drug content uniformity in accordance with proxy United States Pharmacopeia (USP) specification (95%-105% for digoxin and 90%-110% for the other 15 drugs). Weight and drug content uniformity were assessed by comparing weight or drug content of the half tablets with one-half of the mean weight or drug content for all whole tablets in the sample. The percentages by which the weight and drug content of each whole tablet or half tablet differed from sample mean values were calculated. Other relevant physical characteristics of the 16 products were measured. A total of 52 of 320 half tablets (16.2%) and 48 of 320 half tablets (15.0%) fell outside of the proxy USP specification for weight and drug content, respectively. Bromazepam, carvedilol, bisoprolol, losartan, digoxin, and meloxicam half tablets failed the weight and content uniformity test; however, the half tablets for the rest of the medications passed the test. Mean percent weight loss after splitting was less than 1.5% for all drugs. Bromazepam, carvedilol, and digoxin showed the highest powdering loss during the tablet-splitting process. Tablet splitting could be safer and easier when drug- and patient-specific criteria have been met. Tablet size, shape, and hardness may also play a role in the decision to split a tablet or not. Tablets containing drugs with a wide therapeutic index and long half-life might be more suitable candidates for division. Dose variation exceeded a proxy USP specification for more than one-third of sampled half tablets of bromazepam, carvedilol, bisoprolol, and digoxin. Drug content variation in half tablets appeared to be attributed to weight variation due to fragment or powder loss during the splitting process.

Development and preliminary validation of the Parenting around SNAcking Questionnaire (P-SNAQ).

PubMed

Davison, K K; Blake, C E; Kachurak, A; Lumeng, J C; Coffman, D L; Miller, A L; Hughes, S O; Power, T G; Vaughn, A F; Blaine, R E; Younginer, N; Fisher, J O

2018-06-01

Snacking makes significant contributions to children's dietary intake but is poorly understood from a parenting perspective. This research was designed to develop and evaluate the psychometrics of a theoretically grounded, empirically-informed measure of snack parenting. The Parenting around SNAcking Questionnaire (P-SNAQ) was developed using a conceptual model derived from current theory and mixed-methods research to include 20 hypothesized snack parenting practices along 4 parenting dimensions (autonomy support, structure, coercive control and permissiveness). Expert panel evaluation and cognitive interviews were used to refine items and construct definitions. The initial instrument of 105 items was administered to an ethnically diverse, low-income sample of 305 parents (92% mothers) of children aged 1-6 y participating in three existing cohort studies. The sample was randomly split into two equal samples. Exploratory factor analysis was conducted with the first sample to identify snack parenting practices within each parenting dimension, followed by confirmatory factor analysis with the second sample to test the hypothesized factor structure. Internal consistency of sub-scales and associations with existing measures of food parenting practices and styles and child weight status were evaluated. The final P-SNAQ scale included 51 items reflecting 14 snack parenting practices across four parenting dimensions. The factor structure of the P-SNAQ was consistent with prior theoretical frameworks. Internal consistency coefficients were good to very good for 12 out of 14 scales and subscale scores were moderately correlated with previously validated measures. In conclusion, initial evidence suggests that P-SNAQ is a psychometrically sound measure for evaluating a wide range of snack parenting practices in young children. Copyright © 2018 Elsevier Ltd. All rights reserved.

Impact of different study populations on reader behavior and performance metrics: initial results

NASA Astrophysics Data System (ADS)

Gallas, Brandon D.; Pisano, Etta; Cole, Elodia; Myers, Kyle

2017-03-01

The FDA recently completed a study on design methodologies surrounding the Validation of Imaging Premarket Evaluation and Regulation called VIPER. VIPER consisted of five large reader sub-studies to compare the impact of different study populations on reader behavior as seen by sensitivity, specificity, and AUC, the area under the ROC curve (receiver operating characteristic curve). The study investigated different prevalence levels and two kinds of sampling of non-cancer patients: a screening population and a challenge population. The VIPER study compared full-field digital mammography (FFDM) to screenfilm mammography (SFM) for women with heterogeneously dense or extremely dense breasts. All cases and corresponding images were sampled from Digital Mammographic Imaging Screening Trial (DMIST) archives. There were 20 readers (American Board Certified radiologists) for each sub-study, and instead of every reader reading every case (fully-crossed study), readers and cases were split into groups to reduce reader workload and the total number of observations (split-plot study). For data collection, readers first decided whether or not they would recall a patient. Following that decision, they provided an ROC score for how close or far that patient was from the recall decision threshold. Performance results for FFDM show that as prevalence increases to 50%, there is a moderate increase in sensitivity and decrease in specificity, whereas AUC is mainly flat. Regarding precision, the statistical efficiency (ratio of variances) of sensitivity and specificity relative to AUC are 0.66 at best and decrease with prevalence. Analyses comparing modalities and the study populations (screening vs. challenge) are still ongoing.

Impact of Different Study Populations on Reader Behavior and Performance Metrics: Initial Results

PubMed Central

Gallas, Brandon D.; Pisano, Etta; Cole, Elodia; Myers, Kyle

2017-01-01

The FDA recently completed a study on design methodologies surrounding the Validation of Imaging Premarket Evaluation and Regulation called VIPER. VIPER consisted of five large reader sub-studies to compare the impact of different study populations on reader behavior as seen by sensitivity, specificity, and AUC, the area under the ROC curve (receiver operating characteristic curve). The study investigated different prevalence levels and two kinds of sampling of non-cancer patients: a screening population and a challenge population. The VIPER study compared full-field digital mammography (FFDM) to screen-film mammography (SFM) for women with heterogeneously dense or extremely dense breasts. All cases and corresponding images were sampled from Digital Mammographic Imaging Screening Trial (DMIST) archives. There were 20 readers (American Board Certified radiologists) for each sub-study, and instead of every reader reading every case (fully-crossed study), readers and cases were split into groups to reduce reader workload and the total number of observations (split-plot study). For data collection, readers first decided whether or not they would recall a patient. Following that decision, they provided an ROC score for how close or far that patient was from the recall decision threshold. Performance results for FFDM show that as prevalence increases to 50%, there is a moderate increase in sensitivity and decrease in specificity, whereas AUC is mainly flat. Regarding precision, the statistical efficiency (ratio of variances) of sensitivity and specificity relative to AUC are 0.66 at best and decrease with prevalence. Analyses comparing modalities and the study populations (screening vs. challenge) are still ongoing. PMID:28845078

Performance of the score systems Acute Physiology and Chronic Health Evaluation II and III at an interdisciplinary intensive care unit, after customization

PubMed Central

Markgraf, Rainer; Deutschinoff, Gerd; Pientka, Ludger; Scholten, Theo; Lorenz, Cristoph

2001-01-01

Background: Mortality predictions calculated using scoring scales are often not accurate in populations other than those in which the scales were developed because of differences in case-mix. The present study investigates the effect of first-level customization, using a logistic regression technique, on discrimination and calibration of the Acute Physiology and Chronic Health Evaluation (APACHE) II and III scales. Method: Probabilities of hospital death for patients were estimated by applying APACHE II and III and comparing these with observed outcomes. Using the split sample technique, a customized model to predict outcome was developed by logistic regression. The overall goodness-of-fit of the original and the customized models was assessed. Results: Of 3383 consecutive intensive care unit (ICU) admissions over 3 years, 2795 patients could be analyzed, and were split randomly into development and validation samples. The discriminative powers of APACHE II and III were unchanged by customization (areas under the receiver operating characteristic [ROC] curve 0.82 and 0.85, respectively). Hosmer-Lemeshow goodness-of-fit tests showed good calibration for APACHE II, but insufficient calibration for APACHE III. Customization improved calibration for both models, with a good fit for APACHE III as well. However, fit was different for various subgroups. Conclusions: The overall goodness-of-fit of APACHE III mortality prediction was improved significantly by customization, but uniformity of fit in different subgroups was not achieved. Therefore, application of the customized model provides no advantage, because differences in case-mix still limit comparisons of quality of care. PMID:11178223

Dynamic splitting of Gaussian pencil beams in heterogeneity-correction algorithms for radiotherapy with heavy charged particles.

PubMed

Kanematsu, Nobuyuki; Komori, Masataka; Yonai, Shunsuke; Ishizaki, Azusa

2009-04-07

The pencil-beam algorithm is valid only when elementary Gaussian beams are small enough compared to the lateral heterogeneity of a medium, which is not always true in actual radiotherapy with protons and ions. This work addresses a solution for the problem. We found approximate self-similarity of Gaussian distributions, with which Gaussian beams can split into narrower and deflecting daughter beams when their sizes have overreached lateral heterogeneity in the beam-transport calculation. The effectiveness was assessed in a carbon-ion beam experiment in the presence of steep range compensation, where the splitting calculation reproduced a detour effect amounting to about 10% in dose or as large as the lateral particle disequilibrium effect. The efficiency was analyzed in calculations for carbon-ion and proton radiations with a heterogeneous phantom model, where the beam splitting increased computing times by factors of 4.7 and 3.2. The present method generally improves the accuracy of the pencil-beam algorithm without severe inefficiency. It will therefore be useful for treatment planning and potentially other demanding applications.

Detection of the valvular split within the second heart sound using the reassigned smoothed pseudo Wigner–Ville distribution

PubMed Central

2013-01-01

Background In this paper, we developed a novel algorithm to detect the valvular split between the aortic and pulmonary components in the second heart sound which is a valuable medical information. Methods The algorithm is based on the Reassigned smoothed pseudo Wigner–Ville distribution which is a modified time–frequency distribution of the Wigner–Ville distribution. A preprocessing amplitude recovery procedure is carried out on the analysed heart sound to improve the readability of the time–frequency representation. The simulated S2 heart sounds were generated by an overlapping frequency modulated chirp–based model at different valvular split durations. Results Simulated and real heart sounds are processed to highlight the performance of the proposed approach. The algorithm is also validated on real heart sounds of the LGB–IRCM (Laboratoire de Génie biomédical–Institut de recherches cliniques de Montréal) cardiac valve database. The A2–P2 valvular split is accurately detected by processing the obtained RSPWVD representations for both simulated and real data. PMID:23631738

Screening for Moral Injury: The Moral Injury Symptom Scale - Military Version Short Form.

PubMed

Koenig, Harold G; Ames, Donna; Youssef, Nagy A; Oliver, John P; Volk, Fred; Teng, Ellen J; Haynes, Kerry; Erickson, Zachary D; Arnold, Irina; O'Garo, Keisha; Pearce, Michelle

2018-03-26

To develop a short form (SF) of the 45-item multidimensional Moral Injury Symptom Scale - Military Version (MISS-M) to use when screening for moral injury and monitoring treatment response in veterans and active duty military with PTSD. A total of 427 veterans and active duty military with PTSD symptoms were recruited from VA Medical Centers in Augusta, GA; Los Angeles, CA; Durham, NC; Houston, TX; and San Antonio, TX; and from Liberty University, Lynchburg, Virginia. The sample was randomly split in two. In the first half (n = 214), exploratory factor analysis identified the highest loading item on each of the 10 MISS scales (guilt, shame, moral concerns, loss of meaning, difficulty forgiving, loss of trust, self-condemnation, religious struggle, and loss of religious faith) to form the 10-item MISS-M-SF; confirmatory factor analysis was then performed to replicate results in the second half of the sample (n = 213). Internal reliability, test-retest reliability, and convergent, discriminant, and concurrent validity were examined in the overall sample. The study was approved by the institutional review boards and the Research & Development (R&D) Committees at Veterans Administration medical centers in Durham, Los Angeles, Augusta, Houston, and San Antonio, and the Liberty University and Duke University Medical Center institutional review boards. The 10-item MISS-M-SF had a median of 50 and a range of 12-91 (possible range 10-100). Over 70% scored a 9 or 10 (highest possible) on at least one item. Cronbach's alpha was 0.73 (95% CI 0.69-0.76), and test-retest reliability was 0.87 (95% CI 0.79-0.92). Convergent validity with the 45-item MISS-M was r = 0.92. Discriminant validity was demonstrated by relatively weak correlations with social, religious, and physical health constructs (r = 0.21-0.35), and concurrent validity was indicated by strong correlations with PTSD, depression, and anxiety symptoms (r = 0.54-0.58). The MISS-M-SF is a reliable and valid measure of MI symptoms that can be used to screen for MI and monitor response to treatment in veterans and active duty military with PTSD.

Experimental Study On The Effect Of Micro-Cracks On Brazilian Tensile Strength

NASA Astrophysics Data System (ADS)

Wang, Xiangyu

2015-12-01

For coal mine ground control issues, it is necessary to propose a failure criteria accounting for the transversely isotropic behaviors of rocks. Hence, it is very helpful to provide experimental data for the validation of the failure criteria. In this paper, the method for preparing transversely isotropic specimens and the scheme of the Brazilian tensile strength test are presented. Results obtained from Brazilian split tests under dry and water-saturated conditions reflect the effect of the development direction β of the structural plane, such as the bedding fissure, on the tensile strength, ultimate displacement, failure mode, and the whole splitting process. The results show that the tensile strength decreases linearly with increasing β. The softening coefficient of the tensile strength shows a sinusoidal function. The values of the slope and inflection point for the curve vary at the different stages of the Brazilian test. The failure mode of the rock specimen presented in this paper generally coincides with the standard Brazilian splitting failure mode. Based on the test results, the major influencing factors for the Brazilian splitting strength are analyzed and a mathematical model for solving the Brazilian splitting strength is proposed. The findings in this paper would greatly benefit the coal mine ground control studies when the surrounding rocks of interest show severe transversely isotropic behaviors.

Time-dependent Reliability of Dynamic Systems using Subset Simulation with Splitting over a Series of Correlated Time Intervals

DTIC Science & Technology

2013-08-01

cost due to potential warranty costs, repairs and loss of market share. Reliability is the probability that the system will perform its intended...MCMC and splitting sampling schemes. Our proposed SS/ STP method is presented in Section 4, including accuracy bounds and computational effort

On the validity of within-nuclear-family genetic association analysis in samples of extended families.

PubMed

Bureau, Alexandre; Duchesne, Thierry

2015-12-01

Splitting extended families into their component nuclear families to apply a genetic association method designed for nuclear families is a widespread practice in familial genetic studies. Dependence among genotypes and phenotypes of nuclear families from the same extended family arises because of genetic linkage of the tested marker with a risk variant or because of familial specificity of genetic effects due to gene-environment interaction. This raises concerns about the validity of inference conducted under the assumption of independence of the nuclear families. We indeed prove theoretically that, in a conditional logistic regression analysis applicable to disease cases and their genotyped parents, the naive model-based estimator of the variance of the coefficient estimates underestimates the true variance. However, simulations with realistic effect sizes of risk variants and variation of this effect from family to family reveal that the underestimation is negligible. The simulations also show the greater efficiency of the model-based variance estimator compared to a robust empirical estimator. Our recommendation is therefore, to use the model-based estimator of variance for inference on effects of genetic variants.

Division I College Football Concussion Rates Are Higher at Higher Altitudes.

PubMed

Lynall, Robert C; Kerr, Zachary Y; Parr, Matthew S; Hackney, Anthony C; Mihalik, Jason P

2016-02-01

Retrospective cohort. Participating in sports at high altitude may have a protective effect on the brain, according to research studies. Research using validated data-collection methods in a previously unexplored cohort may better estimate the association between concussion injury risk and altitude. To determine the association between concussion rates and altitude during college football games. Athletic trainers from 21 Division I football programs provided exposure and injury data to the National Collegiate Athletic Association (NCAA) Injury Surveillance Program (ISP) from the 2009-2010 to 2013-2014 academic years. The elevation of each stadium was determined. Concussion rates per 1000 athlete-exposures (AEs) were compared in 2 ways, based on the sample of stadium elevations: (1) median split (elevation higher than 178 m or lower than 178 m), and (2) quartile split. Rate ratios (RRs), rate differences, and 95% confidence intervals (CIs) were computed. One hundred sixty-nine concussions were reported over 49 040 AEs (3.45/1000 AEs). Using the median split, the concussion rate above 178 m (RR = 4.18/1000 AEs) was 1.47 times the concussion rate below 178 m (RR = 2.84/1000 AEs; 95% CI: 1.09, 2.00; P = .01). The concussion rate at the highest altitude quartile (higher than 284 m; RR = 5.01/1000 AEs) was 1.67 times greater than the concussion rate at the lowest altitude quartile (lower than 43 m; RR = 3.00/1000 AEs; 95% CI: 1.13, 2.48; P = .01). College football game concussion rates appear to increase at higher altitudes. The clinical significance of this relatively small increase is unknown. Future research should explore potential physiologic underpinnings associated with concussion risk at relatively higher and lower altitudes. Prognosis, level 2b.

Generation of sub-femtoliter droplet by T-junction splitting on microfluidic chips

NASA Astrophysics Data System (ADS)

Yang, Yu-Jun; Feng, Xuan; Xu, Na; Pang, Dai-Wen; Zhang, Zhi-Ling

2013-03-01

In the paper, sub-femtoliter droplets were easily produced by droplet splitting at a simple T-junction with orifice, which did not need expensive equipments, complex photolithography skill, or high energy input. The volume of the daughter droplet was not limited by channel size but controlled by channel geometry and fluidic characteristic. Moreover, single bead sampling and bead quantification in different orders of magnitude of droplet volumes were investigated. The droplets split at our T-junction chip had small volume and monodispersed size and could be produced efficiently, orderly, and controllably.

Split-shift work in relation to stress, health and psychosocial work factors among bus drivers.

PubMed

Ihlström, Jonas; Kecklund, Göran; Anund, Anna

2017-01-01

Shift work has been associated with poor health, sleep and fatigue problems and low satisfaction with working hours. However, one type of shift working, namely split shifts, have received little attention. This study examined stress, health and psychosocial aspects of split-shift schedules among bus drivers in urban transport. A questionnaire was distributed to drivers working more than 70% of full time which 235 drivers in total answered. In general, drivers working split-shift schedules (n = 146) did not differ from drivers not working such shifts (n = 83) as regards any of the outcome variables that were studied. However, when individual perceptions towards split-shift schedules were taken into account, a different picture appeared. Bus drivers who reported problems working split shifts (36%) reported poorer health, higher perceived stress, working hours interfering with social life, lower sleep quality, more persistent fatigue and lower general work satisfaction than those who did not view split shifts as a problem. Moreover, drivers who reported problems with split shifts also perceived lower possibilities to influence working hours, indicating lower work time control. This study indicates that split shifts were not associated with increased stress, poorer health and adverse psychosocial work factors for the entire study sample. However, the results showed that individual differences were important and approximately one third of the drivers reported problems with split shifts, which in turn was associated with stress, poor health and negative psychosocial work conditions. More research is needed to understand the individual and organizational determinants of tolerance to split shifts.

Predicting guar seed splitting by compression between two plates using Hertz theory of contact stresses.

PubMed

Vishwakarma, R K; Shivhare, U S; Nanda, S K

2012-09-01

Hertz's theory of contact stresses was applied to predict the splitting of guar seeds during uni-axial compressive loading between 2 rigid parallel plates. The apparent modulus of elasticity of guar seeds varied between 296.18 and 116.19 MPa when force was applied normal to hilum joint (horizontal position), whereas it varied between 171.86 and 54.18 MPa when force was applied in the direction of hilum joint (vertical position) with in moisture content range of 5.16% to 15.28% (d.b.). At higher moisture contents, the seeds yielded after considerable deformation, thus showing ductile nature. Distribution of stresses below the point of contact were plotted to predict the location of critical point, which was found at 0.44 to 0.64 mm and 0.37 to 0.53 mm below the contact point in vertical and horizontal loading, respectively, depending upon moisture content. The separation of cotyledons from each other initiated before yielding of cotyledons and thus splitting of seed took place. The relationships between apparent modulus of elasticity, principal stresses with moisture content were described using second-order polynomial equations and validated experimentally. Manufacture of guar gum powder requires dehulling and splitting of guar seeds. This article describes splitting behavior of guar seeds under compressive loading. Results of this study may be used for design of dehulling and splitting systems of guar seeds. © 2012 Institute of Food Technologists®

Validation of the Inventaire du Milieu Familial Questionnaire (French version of the Infant/Toddler HOME) into the Brazilian Portuguese language.

PubMed

Sudbrack, Simone; Barbosa, Fernanda P; Mattiello, Rita; Booij, Linda; Estorgato, Geovana R; Dutra, Moisés S; Assunção, Fabiana D de; Nunes, Magda L

2018-04-22

To validate the Brazilian Portuguese version of the Family Environment Assessment questionnaire (Inventaire du Milieu Familial). The validation process was carried out in two stages. First, translation and back-translation were performed, and in the second phase, the questionnaire was applied in 72 families of children between 0 and 24 months for the validation process. The tool consists of the following domains: mother's communication ability; behavior; organization of the physical and temporal environment; collection/quantity of toys; maternal attitude of constant attention toward her baby; diversification of stimuli; baby's behavior. The following was performed for the scale validation: 1 - content analysis (judgment); 2 - construct analysis (factorial analysis - Kaiser-Meyer-Olkin, Bartlett, and Pearson's correlation tests); 3 - criterion analysis (calculation of Cronbach's alpha coefficient, intraclass correlations, and split-half correlations). The mean age of the children was 9±6.7 months, and of these, 35 (48.6%) were males. Most correlations between items and domains were significant. In the factorial analysis of the scale, Kaiser-Meyer-Olkin values were 0.76, Bartlett's test showed a p-value<0.001, and correlation between items and domains showed a p-value<0.01. Regarding the validity, Cronbach's alpha was 0.92 (95% CI: 0.89-0.94). The intraclass correlation among the evaluators was 0.97 (0.96-0.98) and split-half correlations, r: 0.60, with p<0.01. The Portuguese version of the Inventaire du Milieu Familial showed good to excellent performance regarding the assessed psychometric properties. Copyright © 2018. Published by Elsevier Editora Ltda.

Development and validation of an Infertility Stigma Scale for Chinese women.

PubMed

Fu, Bing; Qin, Nan; Cheng, Li; Tang, Guanxiu; Cao, Yi; Yan, Chunli; Huang, Xin; Yan, Pingping; Zhu, Shujuan; Lei, Jun

2015-07-01

To develop and validate a scale of stigma for infertile Chinese women. Infertile women admitted to the Xiangya Hospital, the Second Xiangya Hospital, and the Third Xiangya Hospital of Central South University for treatment were approached to participate in this study. The Infertility Stigma Scale (ISS) development involved: [1] item generation based on literature, interview (experts/patients: N=5/N=20) and related scale; [2] pre-test questionnaire formation with both experts' ratings (N=9) and infertile women's feedbacks (N=30); [3] the component structure assessed by principal components analysis with varimax rotation (N=334); [4] convergent validity assessed with Social Support Rating scale, Self-Esteem scale, Family APGAR Index (N=334); and [5] reliability identified by internal consistency Cronbach's α (N=334), split-half reliability (N=334), test-retest reliability (N=20). This study yielded a 27-item ISS with 4 factors (self-devaluation, social withdrawal, public stigma, and family stigma). Exploratory factor analysis indicated that these 4 factors accounted for 58.17% of total variances. The Cronbach's α, split-half coefficient and test-retest correlation coefficient for the whole scale was 0.94, 0.90, and 0.91, respectively. The associations of the ISS with other measures suggested good convergent validity. The Content Validity Index (CVI) was 0.92. The ISS appears to be a reliable and valid measure to assess levels of stigma experienced by infertile Chinese women. It may be a useful tool to help identify infertile women at greater risks of distress. Copyright © 2014 Elsevier Inc. All rights reserved.

Ionospheric Correction of D-InSAR Using Split-Spectrum Technique and 3D Ionosphere Model in Deformation Monitoring

NASA Astrophysics Data System (ADS)

Chen, Y.; Guo, L.; Wu, J. J.; Chen, Q.; Song, S.

2014-12-01

In Differential Interferometric Synthetic Aperture Radar (D-InSAR) atmosphere effect including troposphere and ionosphere is one of the dominant sources of error in most interferograms, which greatly reduced the accuracy of deformation monitoring. In recent years tropospheric correction especially Zwd in InSAR data processing has ever got widely investigated and got efficiently suppressed. And thus we focused our study on ionospheric correction using two different methods, which are split-spectrum technique and Nequick model, one of the three dimensional electron density models. We processed Wenchuan ALOS PALSAR images, and compared InSAR surface deformation after ionospheric modification using the two approaches mentioned above with ground GPS subsidence observations to validate the effect of split-spectrum method and NeQuick model, further discussed the performance and feasibility of external data and InSAR itself during the study of the elimination of InSAR ionospheric effect.

Energy distribution analysis in boosted HCCI-like / LTGC engines – Understanding the trade-offs to maximize the thermal efficiency

DOE PAGES

Dernotte, Jeremie; Dec, John E.; Ji, Chunsheng

2015-04-14

A detailed understanding of the various factors affecting the trends in gross-indicated thermal efficiency with changes in key operating parameters has been carried out, applied to a one-liter displacement single-cylinder boosted Low-Temperature Gasoline Combustion (LTGC) engine. This work systematically investigates how the supplied fuel energy splits into the following four energy pathways: gross-indicated thermal efficiency, combustion inefficiency, heat transfer and exhaust losses, and how this split changes with operating conditions. Additional analysis is performed to determine the influence of variations in the ratio of specific heat capacities (γ) and the effective expansion ratio, related to the combustion-phasing retard (CA50), onmore » the energy split. Heat transfer and exhaust losses are computed using multiple standard cycle analysis techniques. Furthermore, the various methods are evaluated in order to validate the trends.« less

Improving machine learning reproducibility in genetic association studies with proportional instance cross validation (PICV).

PubMed

Piette, Elizabeth R; Moore, Jason H

2018-01-01

Machine learning methods and conventions are increasingly employed for the analysis of large, complex biomedical data sets, including genome-wide association studies (GWAS). Reproducibility of machine learning analyses of GWAS can be hampered by biological and statistical factors, particularly so for the investigation of non-additive genetic interactions. Application of traditional cross validation to a GWAS data set may result in poor consistency between the training and testing data set splits due to an imbalance of the interaction genotypes relative to the data as a whole. We propose a new cross validation method, proportional instance cross validation (PICV), that preserves the original distribution of an independent variable when splitting the data set into training and testing partitions. We apply PICV to simulated GWAS data with epistatic interactions of varying minor allele frequencies and prevalences and compare performance to that of a traditional cross validation procedure in which individuals are randomly allocated to training and testing partitions. Sensitivity and positive predictive value are significantly improved across all tested scenarios for PICV compared to traditional cross validation. We also apply PICV to GWAS data from a study of primary open-angle glaucoma to investigate a previously-reported interaction, which fails to significantly replicate; PICV however improves the consistency of testing and training results. Application of traditional machine learning procedures to biomedical data may require modifications to better suit intrinsic characteristics of the data, such as the potential for highly imbalanced genotype distributions in the case of epistasis detection. The reproducibility of genetic interaction findings can be improved by considering this variable imbalance in cross validation implementation, such as with PICV. This approach may be extended to problems in other domains in which imbalanced variable distributions are a concern.

Locating the Seventh Cervical Spinous Process: Development and Validation of a Multivariate Model Using Palpation and Personal Information.

PubMed

Ferreira, Ana Paula A; Póvoa, Luciana C; Zanier, José F C; Ferreira, Arthur S

2017-02-01

The aim of this study was to develop and validate a multivariate prediction model, guided by palpation and personal information, for locating the seventh cervical spinous process (C7SP). A single-blinded, cross-sectional study at a primary to tertiary health care center was conducted for model development and temporal validation. One-hundred sixty participants were prospectively included for model development (n = 80) and time-split validation stages (n = 80). The C7SP was located using the thorax-rib static method (TRSM). Participants underwent chest radiography for assessment of the inner body structure located with TRSM and using radio-opaque markers placed over the skin. Age, sex, height, body mass, body mass index, and vertex-marker distance (D V-M ) were used to predict the distance from the C7SP to the vertex (D V-C7 ). Multivariate linear regression modeling, limits of agreement plot, histogram of residues, receiver operating characteristic curves, and confusion tables were analyzed. The multivariate linear prediction model for D V-C7 (in centimeters) was D V-C7 = 0.986D V-M + 0.018(mass) + 0.014(age) - 1.008. Receiver operating characteristic curves had better discrimination of D V-C7 (area under the curve = 0.661; 95% confidence interval = 0.541-0.782; P = .015) than D V-M (area under the curve = 0.480; 95% confidence interval = 0.345-0.614; P = .761), with respective cutoff points at 23.40 cm (sensitivity = 41%, specificity = 63%) and 24.75 cm (sensitivity = 69%, specificity = 52%). The C7SP was correctly located more often when using predicted D V-C7 in the validation sample than when using the TRSM in the development sample: n = 53 (66%) vs n = 32 (40%), P < .001. Better accuracy was obtained when locating the C7SP by use of a multivariate model that incorporates palpation and personal information. Copyright © 2016. Published by Elsevier Inc.

Band splitting in Cd3As2 measured by magnetotransport

NASA Astrophysics Data System (ADS)

Desrat, W.; Krishtopenko, S. S.; Piot, B. A.; Orlita, M.; Consejo, C.; Ruffenach, S.; Knap, W.; Nateprov, A.; Arushanov, E.; Teppe, F.

2018-06-01

Magnetotransport measurements have been performed on (112)-oriented bulk Cd3As2 samples with in situ rotation at low temperature. The frequency analysis of the Shubnikov-de Haas oscillations reveals two weakly separated frequencies arising from two Fermi ellipsoids. The angle dependence of these frequencies is fitted by an analytical expression that we derived for any magnetic field orientation. It is based on an 8 ×8 k .p model which includes the spin-orbit coupling, the crystal field splitting due to tetragonal distortion, and the additional band splitting occurring in noncentrosymmetric crystals. This band splitting is evaluated to a finite value of 30 meV, demonstrating the absence of inversion symmetry in our Cd3As2 crystal.

Motivation for HPV Vaccination Among Young Adult Men: Validation of TTM Decisional Balance and Self-Efficacy Constructs.

PubMed

Fernandez, Anne C; Amoyal, Nicole R; Paiva, Andrea L; Prochaska, James O

2016-01-01

In the United States, 36% of human papillomavirus (HPV)-related cancers occur among men. HPV vaccination can substantially reduce the risk of HPV infection; however, the vast majority of men are unvaccinated. This study developed and validated transtheoretical model-based measures for HPV vaccination in young adult men. Cross-sectional measurement development. Online survey of young adult men. Three hundred twenty-nine mostly college-attending men, ages 18 to 26. Stage of change, decisional balance (pros/cons), and self-efficacy. The sample was randomly split into halves for exploratory principal components analysis (PCA), followed by confirmatory factor analyses (CFA) to test measurement models. Multivariate analyses examined relationships between scales. For decisional balance, PCA revealed two uncorrelated five-item factors (pros α = .78; cons α = .83). For the self-efficacy scale, PCA revealed a single-factor solution (α = .83). CFA confirmed that the two-factor uncorrelated model for decisional balance and a single-factor model for self-efficacy. Follow-up analyses of variance supported the theoretically predicted relationships between stage of change, pros, and self-efficacy. This study resulted in reliable and valid measures of pros and self-efficacy for HPV vaccination that can be used in future clinical research.

Assessment of the structural validity of the domestic violence healthcare providers’ survey questionnaire using a Nigerian sample

PubMed Central

John, Ime A; Lawoko, Stephen

2010-01-01

Abstract: Background: There has been increased advocacy to involve healthcare providers in the prevention of intimate partner violence (IPV) through screening for it in healthcare. Yet, only one in ten providers screen for IPV, suggesting barriers. Understanding the readiness of healthcare providers to screen for IPV is therefore paramount. The Domestic Violence Healthcare Provider Survey Scales (DVHPSS) is a previously validated, comprehensive scale to study readiness of healthcare providers to screen for IPV. However, an understanding of its usefulness in the Sub-Saharan African context remains elusive. The current study undertook to examine the structural validity of the DVHPSS in Nigeria. Methods: Exploratory factor analysis and Cronbach's Alpha were run to reveal the factorial structure and reliability of the instrument/subscales respectively. Established thresholds were used to determine significant factor loadings and alphas coefficient. Results: A six factor model emerged, with 2 factors similar to the original scale, another two differing slightly and a further two factors resulting from a splitting up of the original combination of victim/provider safety to having distinct victim and provider safety subscales. Conclusions: With slight modifications, the DVHPSS can be use to study IPV screening among Nigerian healthcare professionals. Introducing screening protocols could promote better understanding of crucial questions that were lost in the analysis. PMID:21483202

Please Don't Move-Evaluating Motion Artifact From Peripheral Quantitative Computed Tomography Scans Using Textural Features.

PubMed

Rantalainen, Timo; Chivers, Paola; Beck, Belinda R; Robertson, Sam; Hart, Nicolas H; Nimphius, Sophia; Weeks, Benjamin K; McIntyre, Fleur; Hands, Beth; Siafarikas, Aris

Most imaging methods, including peripheral quantitative computed tomography (pQCT), are susceptible to motion artifacts particularly in fidgety pediatric populations. Methods currently used to address motion artifact include manual screening (visual inspection) and objective assessments of the scans. However, previously reported objective methods either cannot be applied on the reconstructed image or have not been tested for distal bone sites. Therefore, the purpose of the present study was to develop and validate motion artifact classifiers to quantify motion artifact in pQCT scans. Whether textural features could provide adequate motion artifact classification performance in 2 adolescent datasets with pQCT scans from tibial and radial diaphyses and epiphyses was tested. The first dataset was split into training (66% of sample) and validation (33% of sample) datasets. Visual classification was used as the ground truth. Moderate to substantial classification performance (J48 classifier, kappa coefficients from 0.57 to 0.80) was observed in the validation dataset with the novel texture-based classifier. In applying the same classifier to the second cross-sectional dataset, a slight-to-fair (κ = 0.01-0.39) classification performance was observed. Overall, this novel textural analysis-based classifier provided a moderate-to-substantial classification of motion artifact when the classifier was specifically trained for the measurement device and population. Classification based on textural features may be used to prescreen obviously acceptable and unacceptable scans, with a subsequent human-operated visual classification of any remaining scans. Copyright © 2017 The International Society for Clinical Densitometry. Published by Elsevier Inc. All rights reserved.

Validation of decisional balance and self-efficacy measures for HPV vaccination in college women.

PubMed

Lipschitz, Jessica M; Fernandez, Anne C; Larson, H Elsa; Blaney, Cerissa L; Meier, Kathy S; Redding, Colleen A; Prochaska, James O; Paiva, Andrea L

2013-01-01

Women younger than 25 years are at greatest risk for human papillomavirus (HPV) infection, including high-risk strains associated with 70% of cervical cancers. Effective model-based measures that can lead to intervention development to increase HPV vaccination rates are necessary. This study validated Transtheoretical Model measures of Decisional Balance and Self-Efficacy for seeking the HPV vaccine in a sample of female college students. Cross-sectional measurement development. Setting. Online survey of undergraduate college students. A total of 340 female students ages 18 to 26 years. Stage of Change, Decisional Balance, and Self-Efficacy. The sample was randomly split into halves for exploratory principal components analyses (PCAs), followed by confirmatory factor analyses (CFAs) to test measurement models. Multivariate analyses examined relationships between constructs. For Decisional Balance, PCA indicated two 4-item factors (Pros -α = .90; and Cons -α = .66). CFA supported a two-factor correlated model, χ(2)(19) = 39.33; p < .01; comparative fit index (CFI) = .97; and average absolute standardized residual statistic (AASR) = .03; with Pros α = .90 and Cons α = .67. For Self-Efficacy, PCA indicated one 6-item factor (α = .84). CFA supported this structure, χ(2)(9) = 50.87; p < .05; CFI = .94; AASR = .03; and α = .90. Multivariate analyses indicated significant cross-stage differences on Pros, Cons, and Self-Efficacy in expected directions. Findings support the internal and external validity of these measures and their use in Transtheoretical Model-tailored interventions. Stage-construct relationships suggest that reducing the Cons of vaccination may be more important for HPV than for behaviors with a true Maintenance stage.

Perioperative Respiratory Adverse Events in Pediatric Ambulatory Anesthesia: Development and Validation of a Risk Prediction Tool.

PubMed

Subramanyam, Rajeev; Yeramaneni, Samrat; Hossain, Mohamed Monir; Anneken, Amy M; Varughese, Anna M

2016-05-01

Perioperative respiratory adverse events (PRAEs) are the most common cause of serious adverse events in children receiving anesthesia. Our primary aim of this study was to develop and validate a risk prediction tool for the occurrence of PRAE from the onset of anesthesia induction until discharge from the postanesthesia care unit in children younger than 18 years undergoing elective ambulatory anesthesia for surgery and radiology. The incidence of PRAE was studied. We analyzed data from 19,059 patients from our department's quality improvement database. The predictor variables were age, sex, ASA physical status, morbid obesity, preexisting pulmonary disorder, preexisting neurologic disorder, and location of ambulatory anesthesia (surgery or radiology). Composite PRAE was defined as the presence of any 1 of the following events: intraoperative bronchospasm, intraoperative laryngospasm, postoperative apnea, postoperative laryngospasm, postoperative bronchospasm, or postoperative prolonged oxygen requirement. Development and validation of the risk prediction tool for PRAE were performed using a split sampling technique to split the database into 2 independent cohorts based on the year when the patient received ambulatory anesthesia for surgery and radiology using logistic regression. A risk score was developed based on the regression coefficients from the validation tool. The performance of the risk prediction tool was assessed by using tests of discrimination and calibration. The overall incidence of composite PRAE was 2.8%. The derivation cohort included 8904 patients, and the validation cohort included 10,155 patients. The risk of PRAE was 3.9% in the development cohort and 1.8% in the validation cohort. Age ≤ 3 years (versus >3 years), ASA physical status II or III (versus ASA physical status I), morbid obesity, preexisting pulmonary disorder, and surgery (versus radiology) significantly predicted the occurrence of PRAE in a multivariable logistic regression model. A risk score in the range of 0 to 3 was assigned to each significant variable in the logistic regression model, and final score for all risk factors ranged from 0 to 11. A cutoff score of 4 was derived from a receiver operating characteristic curve to determine the high-risk category. The model C-statistic and the corresponding SE for the derivation and validation cohort was 0.64 ± 0.01 and 0.63 ± 0.02, respectively. Sensitivity and SE of the risk prediction tool to identify children at risk for PRAE was 77.6 ± 0.02 in the derivation cohort and 76.2 ± 0.03 in the validation cohort. The risk tool developed and validated from our study cohort identified 5 risk factors: age ≤ 3 years (versus >3 years), ASA physical status II and III (versus ASA physical status I), morbid obesity, preexisting pulmonary disorder, and surgery (versus radiology) for PRAE. This tool can be used to provide an individual risk score for each patient to predict the risk of PRAE in the preoperative period.

Cohesive model applied to fracture propagation in Indiana Limestone

NASA Astrophysics Data System (ADS)

Dewers, T. A.; Rinehart, A. J.; Bishop, J. E.

2014-12-01

We apply a cohesive fracture (CF) model to results of short-rod (SR), notched 3-point-bend (N3PB) tests, and Brazil tests in Indiana Limestone. Calibration and validation of the model are performed within a commercial finite element modeling platform. By using a linear traction-displacement softening response for a defined fracture-opening displacement (w1) following peak tensile stress (σcrit), the CF model numerically lumps different spatially distributed inelastic processes occurring at and around fracture tips into a thin zone within an elastic domain. Both the SR and the N3PB test specimen geometries use a notch partway through the sample to control the location of fracture propagation. We develop a mesh for both the SR and N3PB geometries with a narrow cohesive zone in the center of notches. From the Brazil tests, we find a tensile splitting stress (σsplit) of 5.9 MPa. We use a σsplit as the peak tensile stress (σcrit) for all simulations. The Young's modulus (E) and the critical crack opening distance (w1) of the CF model are calibrated against the SR data. The model successfully captures the elastic, yield, peak, and initial and late failure behavior and compares favorably against the N3PB tests. Differences in force-displacement and crack propagation are primarily caused by: more mixed-mode (shear and opening) crack propagation in N3PB than in SR tests, causing a higher peak; and transition from compression (high E) to tension (low E) in a larger volume of the N3PB sample than in the SR geometry. This material is based upon work supported as part of the Center for Frontiers of Subsurface Energy Security, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Award Number DE-SC0001114. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

Approaches of aroma extraction dilution analysis (AEDA) for headspace solid phase microextraction and gas chromatography-olfactometry (HS-SPME-GC-O): Altering sample amount, diluting the sample or adjusting split ratio?

PubMed

Feng, Yunzi; Cai, Yu; Sun-Waterhouse, Dongxiao; Cui, Chun; Su, Guowan; Lin, Lianzhu; Zhao, Mouming

2015-11-15

Aroma extract dilution analysis (AEDA) is widely used for the screening of aroma-active compounds in gas chromatography-olfactometry (GC-O). In this study, three aroma dilution methods, (I) using different test sample volumes, (II) diluting samples, and (III) adjusting the GC injector split ratio, were compared for the analysis of volatiles by using HS-SPME-AEDA. Results showed that adjusting the GC injector split ratio (III) was the most desirable approach, based on the linearity relationships between Ln (normalised peak area) and Ln (normalised flavour dilution factors). Thereafter this dilution method was applied in the analysis of aroma-active compounds in Japanese soy sauce and 36 key odorants were found in this study. The most intense aroma-active components in Japanese soy sauce were: ethyl 2-methylpropanoate, ethyl 2-methylbutanoate, ethyl 3-methylbutanoate, ethyl 4-methylpentanoate, 3-(methylthio)propanal, 1-octen-3-ol, 2-methoxyphenol, 4-ethyl-2-methoxyphenol, 2-methoxy-4-vinylphenol, 2-phenylethanol, and 4-hydroxy-5-ethyl-2-methyl-3(2H)-furanone. Copyright © 2015. Published by Elsevier Ltd.

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

None

Oak Ridge Associated Universities (ORAU), under the Oak Ridge Institute for Science and Education (ORISE) contract, collected split surface water samples with Nuclear Fuel Services (NFS) representatives on November 15, 2012. Representatives from the U.S. Nuclear Regulatory Commission and Tennessee Department of Environment and Conservation were also in attendance. Samples were collected at four surface water stations, as required in the approved Request for Technical Assistance number 11-018. These stations included Nolichucky River upstream (NRU), Nolichucky River downstream (NRD), Martin Creek upstream (MCU), and Martin Creek downstream (MCD). Both ORAU and NFS performed gross alpha and gross beta analyses, andmore » the results are compared using the duplicate error ratio (DER), also known as the normalized absolute difference. A DER {<=} 3 indicates that, at a 99% confidence interval, split sample results do not differ significantly when compared to their respective one standard deviation (sigma) uncertainty (ANSI N42.22). The NFS split sample report does not specify the confidence level of reported uncertainties (NFS 2012). Therefore, standard two sigma reporting is assumed and uncertainty values were divided by 1.96. In conclusion, all DER values were less than 3 and results are consistent with low (e.g., background) concentrations.« less

Multiple origins of interdependent endosymbiotic complexes in a genus of cicadas.

PubMed

Łukasik, Piotr; Nazario, Katherine; Van Leuven, James T; Campbell, Matthew A; Meyer, Mariah; Michalik, Anna; Pessacq, Pablo; Simon, Chris; Veloso, Claudio; McCutcheon, John P

2018-01-09

Bacterial endosymbionts that provide nutrients to hosts often have genomes that are extremely stable in structure and gene content. In contrast, the genome of the endosymbiont Hodgkinia cicadicola has fractured into multiple distinct lineages in some species of the cicada genus Tettigades To better understand the frequency, timing, and outcomes of Hodgkinia lineage splitting throughout this cicada genus, we sampled cicadas over three field seasons in Chile and performed genomics and microscopy on representative samples. We found that a single ancestral Hodgkinia lineage has split at least six independent times in Tettigades over the last 4 million years, resulting in complexes of between two and six distinct Hodgkinia lineages per host. Individual genomes in these symbiotic complexes differ dramatically in relative abundance, genome size, organization, and gene content. Each Hodgkinia lineage retains a small set of core genes involved in genetic information processing, but the high level of gene loss experienced by all genomes suggests that extensive sharing of gene products among symbiont cells must occur. In total, Hodgkinia complexes that consist of multiple lineages encode nearly complete sets of genes present on the ancestral single lineage and presumably perform the same functions as symbionts that have not undergone splitting. However, differences in the timing of the splits, along with dissimilar gene loss patterns on the resulting genomes, have led to very different outcomes of lineage splitting in extant cicadas.

Nuclear Archeology in a Bottle: Evidence of Pre-Trinity U.S. Weapons Activities from a Waste Burial Site

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

Schwantes, Jon M.; Douglas, Matthew; Bonde, Steven E.

2009-02-15

During World War II, the Hanford Site in Washington was chosen for plutonium production. In 2004, a bottle containing a sample of plutonium was recovered from a Hanford waste trench. Isotopic age dating indicated the sample was separated from the fuel pellet 64 ±2.8 years earlier. Detectable products of secondary nuclear reactions, such as 22Na, proved useful as 1) a detectable analog for alpha emitting actinides, 2) an indicator of sample splitting, and 3) a measure of the time since sample splitting. The sample origin was identified as the X-10 reactor, Oak Ridge, TN. Corroborated by historical documents, we concludedmore » this sample was part of the first batch of Pu separated at T-Plant, Hanford, the world’s first industrial-scale reprocessing facility, on December 9, 1944.« less

Helical Face Gear Development Under the Enhanced Rotorcraft Drive System Program

NASA Technical Reports Server (NTRS)

Heath, Gregory F.; Slaughter, Stephen C.; Fisher, David J.; Lewicki, David G.; Fetty, Jason

2011-01-01

U.S. Army goals for the Enhanced Rotorcraft Drive System Program are to achieve a 40 percent increase in horsepower to weight ratio, a 15 dB reduction in drive system generated noise, 30 percent reduction in drive system operating, support, and acquisition cost, and 75 percent automatic detection of critical mechanical component failures. Boeing s technology transition goals are that the operational endurance level of the helical face gearing and related split-torque designs be validated to a TRL 6, and that analytical and manufacturing tools be validated. Helical face gear technology is being developed in this project to augment, and transition into, a Boeing AH-64 Block III split-torque face gear main transmission stage, to yield increased power density and reduced noise. To date, helical face gear grinding development on Northstar s new face gear grinding machine and pattern-development tests at the NASA Glenn/U.S. Army Research Laboratory have been completed and are described.

[Discrimination of types of polyacrylamide based on near infrared spectroscopy coupled with least square support vector machine].

PubMed

Zhang, Hong-Guang; Yang, Qin-Min; Lu, Jian-Gang

2014-04-01

In this paper, a novel discriminant methodology based on near infrared spectroscopic analysis technique and least square support vector machine was proposed for rapid and nondestructive discrimination of different types of Polyacrylamide. The diffuse reflectance spectra of samples of Non-ionic Polyacrylamide, Anionic Polyacrylamide and Cationic Polyacrylamide were measured. Then principal component analysis method was applied to reduce the dimension of the spectral data and extract of the principal compnents. The first three principal components were used for cluster analysis of the three different types of Polyacrylamide. Then those principal components were also used as inputs of least square support vector machine model. The optimization of the parameters and the number of principal components used as inputs of least square support vector machine model was performed through cross validation based on grid search. 60 samples of each type of Polyacrylamide were collected. Thus a total of 180 samples were obtained. 135 samples, 45 samples for each type of Polyacrylamide, were randomly split into a training set to build calibration model and the rest 45 samples were used as test set to evaluate the performance of the developed model. In addition, 5 Cationic Polyacrylamide samples and 5 Anionic Polyacrylamide samples adulterated with different proportion of Non-ionic Polyacrylamide were also prepared to show the feasibilty of the proposed method to discriminate the adulterated Polyacrylamide samples. The prediction error threshold for each type of Polyacrylamide was determined by F statistical significance test method based on the prediction error of the training set of corresponding type of Polyacrylamide in cross validation. The discrimination accuracy of the built model was 100% for prediction of the test set. The prediction of the model for the 10 mixing samples was also presented, and all mixing samples were accurately discriminated as adulterated samples. The overall results demonstrate that the discrimination method proposed in the present paper can rapidly and nondestructively discriminate the different types of Polyacrylamide and the adulterated Polyacrylamide samples, and offered a new approach to discriminate the types of Polyacrylamide.

Measurement of kT splitting scales in W→ℓν events at [Formula: see text] with the ATLAS detector.

PubMed

Aad, G; Abajyan, T; Abbott, B; Abdallah, J; Abdel Khalek, S; Abdelalim, A A; Abdinov, O; Aben, R; Abi, B; Abolins, M; AbouZeid, O S; Abramowicz, H; Abreu, H; Acharya, B S; Adamczyk, L; Adams, D L; Addy, T N; Adelman, J; Adomeit, S; Adragna, P; Adye, T; Aefsky, S; Aguilar-Saavedra, J A; Agustoni, M; Ahlen, S P; Ahles, F; Ahmad, A; Ahsan, M; Aielli, G; Åkesson, T P A; Akimoto, G; Akimov, A V; Alam, M A; Albert, J; Albrand, S; Aleksa, M; Aleksandrov, I N; Alessandria, F; Alexa, C; Alexander, G; Alexandre, G; Alexopoulos, T; Alhroob, M; Aliev, M; Alimonti, G; Alison, J; Allbrooke, B M M; Allison, L J; Allport, P P; Allwood-Spiers, S E; Almond, J; Aloisio, A; Alon, R; Alonso, A; Alonso, F; Altheimer, A; Alvarez Gonzalez, B; Alviggi, M G; Amako, K; Amelung, C; Ammosov, V V; Amor Dos Santos, S P; Amorim, A; Amoroso, S; Amram, N; Anastopoulos, C; Ancu, L S; Andari, N; Andeen, T; Anders, C F; Anders, G; Anderson, K J; Andreazza, A; Andrei, V; Anduaga, X S; Angelidakis, S; Anger, P; Angerami, A; Anghinolfi, F; Anisenkov, A; Anjos, N; Annovi, A; Antonaki, A; Antonelli, M; Antonov, A; Antos, J; Anulli, F; Aoki, M; Aperio Bella, L; Apolle, R; Arabidze, G; Aracena, I; Arai, Y; Arce, A T H; Arfaoui, S; Arguin, J-F; Argyropoulos, S; Arik, E; Arik, M; Armbruster, A J; Arnaez, O; Arnal, V; Artamonov, A; Artoni, G; Arutinov, D; Asai, S; Ask, S; Åsman, B; Asquith, L; Assamagan, K; Astalos, R; Astbury, A; Atkinson, M; Auerbach, B; Auge, E; Augsten, K; Aurousseau, M; Avolio, G; Axen, D; Azuelos, G; Azuma, Y; Baak, M A; Baccaglioni, G; Bacci, C; Bach, A M; Bachacou, H; Bachas, K; Backes, M; Backhaus, M; Backus Mayes, J; Badescu, E; Bagnaia, P; Bai, Y; Bailey, D C; Bain, T; Baines, J T; Baker, O K; Baker, S; Balek, P; Balli, F; Banas, E; Banerjee, P; Banerjee, Sw; Banfi, D; Bangert, A; Bansal, V; Bansil, H S; Barak, L; Baranov, S P; Barber, T; Barberio, E L; Barberis, D; Barbero, M; Bardin, D Y; Barillari, T; Barisonzi, M; Barklow, T; Barlow, N; Barnett, B M; Barnett, R M; Baroncelli, A; Barone, G; Barr, A J; Barreiro, F; Barreiro Guimarães da Costa, J; Bartoldus, R; Barton, A E; Bartsch, V; Basye, A; Bates, R L; Batkova, L; Batley, J R; Battaglia, A; Battistin, M; Bauer, F; Bawa, H S; Beale, S; Beau, T; Beauchemin, P H; Beccherle, R; Bechtle, P; Beck, H P; Becker, K; Becker, S; Beckingham, M; Becks, K H; Beddall, A J; Beddall, A; Bedikian, S; Bednyakov, V A; Bee, C P; Beemster, L J; Beermann, T A; Begel, M; Behar Harpaz, S; Belanger-Champagne, C; Bell, P J; Bell, W H; Bella, G; Bellagamba, L; Bellomo, M; Belloni, A; Beloborodova, O; Belotskiy, K; Beltramello, O; Benary, O; Benchekroun, D; Bendtz, K; Benekos, N; Benhammou, Y; Benhar Noccioli, E; Benitez Garcia, J A; Benjamin, D P; Benoit, M; Bensinger, J R; Benslama, K; Bentvelsen, S; Berge, D; Bergeaas Kuutmann, E; Berger, N; Berghaus, F; Berglund, E; Beringer, J; Bernat, P; Bernhard, R; Bernius, C; Bernlochner, F U; Berry, T; Bertella, C; Bertin, A; Bertolucci, F; Besana, M I; Besjes, G J; Besson, N; Bethke, S; Bhimji, W; Bianchi, R M; Bianchini, L; Bianco, M; Biebel, O; Bieniek, S P; Bierwagen, K; Biesiada, J; Biglietti, M; Bilokon, H; Bindi, M; Binet, S; Bingul, A; Bini, C; Biscarat, C; Bittner, B; Black, C W; Black, J E; Black, K M; Blair, R E; Blanchard, J-B; Blazek, T; Bloch, I; Blocker, C; Blocki, J; Blum, W; Blumenschein, U; Bobbink, G J; Bobrovnikov, V S; Bocchetta, S S; Bocci, A; Boddy, C R; Boehler, M; Boek, J; Boek, T T; Boelaert, N; Bogaerts, J A; Bogdanchikov, A; Bogouch, A; Bohm, C; Bohm, J; Boisvert, V; Bold, T; Boldea, V; Bolnet, N M; Bomben, M; Bona, M; Boonekamp, M; Bordoni, S; Borer, C; Borisov, A; Borissov, G; Borjanovic, I; Borri, M; Borroni, S; Bortfeldt, J; Bortolotto, V; Bos, K; Boscherini, D; Bosman, M; Boterenbrood, H; Bouchami, J; Boudreau, J; Bouhova-Thacker, E V; Boumediene, D; Bourdarios, C; Bousson, N; Boutouil, S; Boveia, A; Boyd, J; Boyko, I R; Bozovic-Jelisavcic, I; Bracinik, J; Branchini, P; Brandt, A; Brandt, G; Brandt, O; Bratzler, U; Brau, B; Brau, J E; Braun, H M; Brazzale, S F; Brelier, B; Bremer, J; Brendlinger, K; Brenner, R; Bressler, S; Bristow, T M; Britton, D; Brochu, F M; Brock, I; Brock, R; Broggi, F; Bromberg, C; Bronner, J; Brooijmans, G; Brooks, T; Brooks, W K; Brown, G; Bruckman de Renstrom, P A; Bruncko, D; Bruneliere, R; Brunet, S; Bruni, A; Bruni, G; Bruschi, M; Bryngemark, L; Buanes, T; Buat, Q; Bucci, F; Buchanan, J; Buchholz, P; Buckingham, R M; Buckley, A G; Buda, S I; Budagov, I A; Budick, B; Bugge, L; Bulekov, O; Bundock, A C; Bunse, M; Buran, T; Burckhart, H; Burdin, S; Burgess, T; Burke, S; Busato, E; Büscher, V; Bussey, P; Buszello, C P; Butler, B; Butler, J M; Buttar, C M; Butterworth, J M; Buttinger, W; Byszewski, M; Cabrera Urbán, S; Caforio, D; Cakir, O; Calafiura, P; Calderini, G; Calfayan, P; Calkins, R; Caloba, L P; Caloi, R; Calvet, D; Calvet, S; Camacho Toro, R; Camarri, P; Cameron, D; Caminada, L M; Caminal Armadans, R; Campana, S; Campanelli, M; Canale, V; Canelli, F; Canepa, A; Cantero, J; Cantrill, R; Cao, T; Capeans Garrido, M D M; Caprini, I; Caprini, M; Capriotti, D; Capua, M; Caputo, R; Cardarelli, R; Carli, T; Carlino, G; Carminati, L; Caron, S; Carquin, E; Carrillo-Montoya, G D; Carter, A A; Carter, J R; Carvalho, J; Casadei, D; Casado, M P; Cascella, M; Caso, C; Castaneda-Miranda, E; Castillo Gimenez, V; Castro, N F; Cataldi, G; Catastini, P; Catinaccio, A; Catmore, J R; Cattai, A; Cattani, G; Caughron, S; Cavaliere, V; Cavalleri, P; Cavalli, D; Cavalli-Sforza, M; Cavasinni, V; Ceradini, F; Cerqueira, A S; Cerri, A; Cerrito, L; Cerutti, F; Cetin, S A; Chafaq, A; Chakraborty, D; Chalupkova, I; Chan, K; Chang, P; Chapleau, B; Chapman, J D; Chapman, J W; Charlton, D G; Chavda, V; Chavez Barajas, C A; Cheatham, S; Chekanov, S; Chekulaev, S V; Chelkov, G A; Chelstowska, M A; Chen, C; Chen, H; Chen, S; Chen, X; Chen, Y; Cheng, Y; Cheplakov, A; Cherkaoui El Moursli, R; Chernyatin, V; Cheu, E; Cheung, S L; Chevalier, L; Chiefari, G; Chikovani, L; Childers, J T; Chilingarov, A; Chiodini, G; Chisholm, A S; Chislett, R T; Chitan, A; Chizhov, M V; Choudalakis, G; Chouridou, S; Chow, B K B; Christidi, I A; Christov, A; Chromek-Burckhart, D; Chu, M L; Chudoba, J; Ciapetti, G; Ciftci, A K; Ciftci, R; Cinca, D; Cindro, V; Ciocio, A; Cirilli, M; Cirkovic, P; Citron, Z H; Citterio, M; Ciubancan, M; Clark, A; Clark, P J; Clarke, R N; Cleland, W; Clemens, J C; Clement, B; Clement, C; Coadou, Y; Cobal, M; Coccaro, A; Cochran, J; Coffey, L; Cogan, J G; Coggeshall, J; Colas, J; Cole, S; Colijn, A P; Collins, N J; Collins-Tooth, C; Collot, J; Colombo, T; Colon, G; Compostella, G; Conde Muiño, P; Coniavitis, E; Conidi, M C; Consonni, S M; Consorti, V; Constantinescu, S; Conta, C; Conti, G; Conventi, F; Cooke, M; Cooper, B D; Cooper-Sarkar, A M; Cooper-Smith, N J; Copic, K; Cornelissen, T; Corradi, M; Corriveau, F; Cortes-Gonzalez, A; Cortiana, G; Costa, G; Costa, M J; Costanzo, D; Côté, D; Cottin, G; Courneyea, L; Cowan, G; Cox, B E; Cranmer, K; Crépé-Renaudin, S; Crescioli, F; Cristinziani, M; Crosetti, G; Cuciuc, C-M; Cuenca Almenar, C; Cuhadar Donszelmann, T; Cummings, J; Curatolo, M; Curtis, C J; Cuthbert, C; Cwetanski, P; Czirr, H; Czodrowski, P; Czyczula, Z; D'Auria, S; D'Onofrio, M; D'Orazio, A; Da Cunha Sargedas De Sousa, M J; Da Via, C; Dabrowski, W; Dafinca, A; Dai, T; Dallaire, F; Dallapiccola, C; Dam, M; Damiani, D S; Danielsson, H O; Dao, V; Darbo, G; Darlea, G L; Darmora, S; Dassoulas, J A; Davey, W; Davidek, T; Davidson, N; Davidson, R; Davies, E; Davies, M; Davignon, O; Davison, A R; Davygora, Y; Dawe, E; Dawson, I; Daya-Ishmukhametova, R K; De, K; de Asmundis, R; De Castro, S; De Cecco, S; de Graat, J; De Groot, N; de Jong, P; De La Taille, C; De la Torre, H; De Lorenzi, F; De Nooij, L; De Pedis, D; De Salvo, A; De Sanctis, U; De Santo, A; De Vivie De Regie, J B; De Zorzi, G; Dearnaley, W J; Debbe, R; Debenedetti, C; Dechenaux, B; Dedovich, D V; Degenhardt, J; Del Peso, J; Del Prete, T; Delemontex, T; Deliyergiyev, M; Dell'Acqua, A; Dell'Asta, L; Della Pietra, M; Della Volpe, D; Delmastro, M; Delsart, P A; Deluca, C; Demers, S; Demichev, M; Demirkoz, B; Denisov, S P; Derendarz, D; Derkaoui, J E; Derue, F; Dervan, P; Desch, K; Deviveiros, P O; Dewhurst, A; DeWilde, B; Dhaliwal, S; Dhullipudi, R; Di Ciaccio, A; Di Ciaccio, L; Di Donato, C; Di Girolamo, A; Di Girolamo, B; Di Luise, S; Di Mattia, A; Di Micco, B; Di Nardo, R; Di Simone, A; Di Sipio, R; Diaz, M A; Diehl, E B; Dietrich, J; Dietzsch, T A; Diglio, S; Dindar Yagci, K; Dingfelder, J; Dinut, F; Dionisi, C; Dita, P; Dita, S; Dittus, F; Djama, F; Djobava, T; do Vale, M A B; Do Valle Wemans, A; Doan, T K O; Dobbs, M; Dobos, D; Dobson, E; Dodd, J; Doglioni, C; Doherty, T; Dohmae, T; Doi, Y; Dolejsi, J; Dolezal, Z; Dolgoshein, B A; Donadelli, M; Donini, J; Dopke, J; Doria, A; Dos Anjos, A; Dotti, A; Dova, M T; Doyle, A T; Dressnandt, N; Dris, M; Dubbert, J; Dube, S; Dubreuil, E; Duchovni, E; Duckeck, G; Duda, D; Dudarev, A; Dudziak, F; Duerdoth, I P; Duflot, L; Dufour, M-A; Duguid, L; Dührssen, M; Dunford, M; Duran Yildiz, H; Düren, M; Duxfield, R; Dwuznik, M; Ebenstein, W L; Ebke, J; Eckweiler, S; Edson, W; Edwards, C A; Edwards, N C; Ehrenfeld, W; Eifert, T; Eigen, G; Einsweiler, K; Eisenhandler, E; Ekelof, T; El Kacimi, M; Ellert, M; Elles, S; Ellinghaus, F; Ellis, K; Ellis, N; Elmsheuser, J; Elsing, M; Emeliyanov, D; Enari, Y; Engelmann, R; Engl, A; Epp, B; Erdmann, J; Ereditato, A; Eriksson, D; Ernst, J; Ernst, M; Ernwein, J; Errede, D; Errede, S; Ertel, E; Escalier, M; Esch, H; Escobar, C; Espinal Curull, X; Esposito, B; Etienne, F; Etienvre, A I; Etzion, E; Evangelakou, D; Evans, H; Fabbri, L; Fabre, C; Facini, G; Fakhrutdinov, R M; Falciano, S; Fang, Y; Fanti, M; Farbin, A; Farilla, A; Farley, J; Farooque, T; Farrell, S; Farrington, S M; Farthouat, P; Fassi, F; Fassnacht, P; Fassouliotis, D; Fatholahzadeh, B; Favareto, A; Fayard, L; Federic, P; Fedin, O L; Fedorko, W; Fehling-Kaschek, M; Feligioni, L; Feng, C; Feng, E J; Fenyuk, A B; Ferencei, J; Fernando, W; Ferrag, S; Ferrando, J; Ferrara, V; Ferrari, A; Ferrari, P; Ferrari, R; Ferreira de Lima, D E; Ferrer, A; Ferrere, D; Ferretti, C; Ferretto Parodi, A; Fiascaris, M; Fiedler, F; Filipčič, A; Filthaut, F; Fincke-Keeler, M; Fiolhais, M C N; Fiorini, L; Firan, A; Fischer, J; Fisher, M J; Fitzgerald, E A; Flechl, M; Fleck, I; Fleischmann, P; Fleischmann, S; Fletcher, G T; Fletcher, G; Flick, T; Floderus, A; Flores Castillo, L R; Florez Bustos, A C; Flowerdew, M J; Fonseca Martin, T; Formica, A; Forti, A; Fortin, D; Fournier, D; Fowler, A J; Fox, H; Francavilla, P; Franchini, M; Franchino, S; Francis, D; Frank, T; Franklin, M; Franz, S; Fraternali, M; Fratina, S; French, S T; Friedrich, C; Friedrich, F; Froidevaux, D; Frost, J A; Fukunaga, C; Fullana Torregrosa, E; Fulsom, B G; Fuster, J; Gabaldon, C; Gabizon, O; Gadatsch, S; Gadfort, T; Gadomski, S; Gagliardi, G; Gagnon, P; Galea, C; Galhardo, B; Gallas, E J; Gallo, V; Gallop, B J; Gallus, P; Gan, K K; Gandrajula, R P; Gao, Y S; Gaponenko, A; Garay Walls, F M; Garberson, F; García, C; García Navarro, J E; Garcia-Sciveres, M; Gardner, R W; Garelli, N; Garonne, V; Gatti, C; Gaudio, G; Gaur, B; Gauthier, L; Gauzzi, P; Gavrilenko, I L; Gay, C; Gaycken, G; Gazis, E N; Ge, P; Gecse, Z; Gee, C N P; Geerts, D A A; Geich-Gimbel, Ch; Gellerstedt, K; Gemme, C; Gemmell, A; Genest, M H; Gentile, S; George, M; George, S; Gerbaudo, D; Gerlach, P; Gershon, A; Geweniger, C; Ghazlane, H; Ghodbane, N; Giacobbe, B; Giagu, S; Giangiobbe, V; Gianotti, F; Gibbard, B; Gibson, A; Gibson, S M; Gilchriese, M; Gillam, T P S; Gillberg, D; Gillman, A R; Gingrich, D M; Ginzburg, J; Giokaris, N; Giordani, M P; Giordano, R; Giorgi, F M; Giovannini, P; Giraud, P F; Giugni, D; Giunta, M; Gjelsten, B K; Gladilin, L K; Glasman, C; Glatzer, J; Glazov, A; Glonti, G L; Goddard, J R; Godfrey, J; Godlewski, J; Goebel, M; Goeringer, C; Goldfarb, S; Golling, T; Golubkov, D; Gomes, A; Gomez Fajardo, L S; Gonçalo, R; Goncalves Pinto Firmino Da Costa, J; Gonella, L; González de la Hoz, S; Gonzalez Parra, G; Gonzalez Silva, M L; Gonzalez-Sevilla, S; Goodson, J J; Goossens, L; Göpfert, T; Gorbounov, P A; Gordon, H A; Gorelov, I; Gorfine, G; Gorini, B; Gorini, E; Gorišek, A; Gornicki, E; Goshaw, A T; Gössling, C; Gostkin, M I; Gough Eschrich, I; Gouighri, M; Goujdami, D; Goulette, M P; Goussiou, A G; Goy, C; Gozpinar, S; Graber, L; Grabowska-Bold, I; Grafström, P; Grahn, K-J; Gramstad, E; Grancagnolo, F; Grancagnolo, S; Grassi, V; Gratchev, V; Gray, H M; Gray, J A; Graziani, E; Grebenyuk, O G; Greenshaw, T; Greenwood, Z D; Gregersen, K; Gregor, I M; Grenier, P; Griffiths, J; Grigalashvili, N; Grillo, A A; Grimm, K; Grinstein, S; Gris, Ph; Grishkevich, Y V; Grivaz, J-F; Grohs, J P; Grohsjean, A; Gross, E; Grosse-Knetter, J; Groth-Jensen, J; Grybel, K; Guest, D; Gueta, O; Guicheney, C; Guido, E; Guillemin, T; Guindon, S; Gul, U; Gunther, J; Guo, B; Guo, J; Gutierrez, P; Guttman, N; Gutzwiller, O; Guyot, C; Gwenlan, C; Gwilliam, C B; Haas, A; Haas, S; Haber, C; Hadavand, H K; Hadley, D R; Haefner, P; Hajduk, Z; Hakobyan, H; Hall, D; Halladjian, G; Hamacher, K; Hamal, P; Hamano, K; Hamer, M; Hamilton, A; Hamilton, S; Han, L; Hanagaki, K; Hanawa, K; Hance, M; Handel, C; Hanke, P; Hansen, J R; Hansen, J B; Hansen, J D; Hansen, P H; Hansson, P; Hara, K; Harenberg, T; Harkusha, S; Harper, D; Harrington, R D; Harris, O M; Hartert, J; Hartjes, F; Haruyama, T; Harvey, A; Hasegawa, S; Hasegawa, Y; Hassani, S; Haug, S; Hauschild, M; Hauser, R; Havranek, M; Hawkes, C M; Hawkings, R J; Hawkins, A D; Hayakawa, T; Hayashi, T; Hayden, D; Hays, C P; Hayward, H S; Haywood, S J; Head, S J; Heck, T; Hedberg, V; Heelan, L; Heim, S; Heinemann, B; Heisterkamp, S; Helary, L; Heller, C; Heller, M; Hellman, S; Hellmich, D; Helsens, C; Henderson, R C W; Henke, M; Henrichs, A; Henriques Correia, A M; Henrot-Versille, S; Hensel, C; Hernandez, C M; Hernández Jiménez, Y; Herrberg, R; Herten, G; Hertenberger, R; Hervas, L; Hesketh, G G; Hessey, N P; Hickling, R; Higón-Rodriguez, E; Hill, J C; Hiller, K H; Hillert, S; Hillier, S J; Hinchliffe, I; Hines, E; Hirose, M; Hirsch, F; Hirschbuehl, D; Hobbs, J; Hod, N; Hodgkinson, M C; Hodgson, P; Hoecker, A; Hoeferkamp, M R; Hoffman, J; Hoffmann, D; Hohlfeld, M; Holmgren, S O; Holy, T; Holzbauer, J L; Hong, T M; Hooft van Huysduynen, L; Hostachy, J-Y; Hou, S; Hoummada, A; Howard, J; Howarth, J; Hrabovsky, M; Hristova, I; Hrivnac, J; Hryn'ova, T; Hsu, P J; Hsu, S-C; Hu, D; Hubacek, Z; Hubaut, F; Huegging, F; Huettmann, A; Huffman, T B; Hughes, E W; Hughes, G; Huhtinen, M; Hülsing, T A; Hurwitz, M; Huseynov, N; Huston, J; Huth, J; Iacobucci, G; Iakovidis, G; Ibbotson, M; Ibragimov, I; Iconomidou-Fayard, L; Idarraga, J; Iengo, P; Igonkina, O; Ikegami, Y; Ikematsu, K; Ikeno, M; Iliadis, D; Ilic, N; Ince, T; Ioannou, P; Iodice, M; Iordanidou, K; Ippolito, V; Irles Quiles, A; Isaksson, C; Ishino, M; Ishitsuka, M; Ishmukhametov, R; Issever, C; Istin, S; Ivashin, A V; Iwanski, W; Iwasaki, H; Izen, J M; Izzo, V; Jackson, B; Jackson, J N; Jackson, P; Jaekel, M R; Jain, V; Jakobs, K; Jakobsen, S; Jakoubek, T; Jakubek, J; Jamin, D O; Jana, D K; Jansen, E; Jansen, H; Janssen, J; Jantsch, A; Janus, M; Jared, R C; Jarlskog, G; Jeanty, L; Jeng, G-Y; Jen-La Plante, I; Jennens, D; Jenni, P; Jeske, C; Jež, P; Jézéquel, S; Jha, M K; Ji, H; Ji, W; Jia, J; Jiang, Y; Jimenez Belenguer, M; Jin, S; Jinnouchi, O; Joergensen, M D; Joffe, D; Johansen, M; Johansson, K E; Johansson, P; Johnert, S; Johns, K A; Jon-And, K; Jones, G; Jones, R W L; Jones, T J; Joram, C; Jorge, P M; Joshi, K D; Jovicevic, J; Jovin, T; Ju, X; Jung, C A; Jungst, R M; Juranek, V; Jussel, P; Juste Rozas, A; Kabana, S; Kaci, M; Kaczmarska, A; Kadlecik, P; Kado, M; Kagan, H; Kagan, M; Kajomovitz, E; Kalinin, S; Kama, S; Kanaya, N; Kaneda, M; Kaneti, S; Kanno, T; Kantserov, V A; Kanzaki, J; Kaplan, B; Kapliy, A; Kar, D; Karagounis, M; Karakostas, K; Karnevskiy, M; Kartvelishvili, V; Karyukhin, A N; Kashif, L; Kasieczka, G; Kass, R D; Kastanas, A; Kataoka, Y; Katzy, J; Kaushik, V; Kawagoe, K; Kawamoto, T; Kawamura, G; Kazama, S; Kazanin, V F; Kazarinov, M Y; Keeler, R; Keener, P T; Kehoe, R; Keil, M; Keller, J S; Kenyon, M; Keoshkerian, H; Kepka, O; Kerschen, N; Kerševan, B P; Kersten, S; Kessoku, K; Keung, J; Khalil-Zada, F; Khandanyan, H; Khanov, A; Kharchenko, D; Khodinov, A; Khomich, A; Khoo, T J; Khoriauli, G; Khoroshilov, A; Khovanskiy, V; Khramov, E; Khubua, J; Kim, H; Kim, S H; Kimura, N; Kind, O; King, B T; King, M; King, R S B; Kirk, J; Kiryunin, A E; Kishimoto, T; Kisielewska, D; Kitamura, T; Kittelmann, T; Kiuchi, K; Kladiva, E; Klein, M; Klein, U; Kleinknecht, K; Klemetti, M; Klier, A; Klimek, P; Klimentov, A; Klingenberg, R; Klinger, J A; Klinkby, E B; Klioutchnikova, T; Klok, P F; Klous, S; Kluge, E-E; Kluge, T; Kluit, P; Kluth, S; Kneringer, E; Knoops, E B F G; Knue, A; Ko, B R; Kobayashi, T; Kobel, M; Kocian, M; Kodys, P; Koenig, S; Koetsveld, F; Koevesarki, P; Koffas, T; Koffeman, E; Kogan, L A; Kohlmann, S; Kohn, F; Kohout, Z; Kohriki, T; Koi, T; Kolanoski, H; Kolesnikov, V; Koletsou, I; Koll, J; Komar, A A; Komori, Y; Kondo, T; Köneke, K; König, A C; Kono, T; Kononov, A I; Konoplich, R; Konstantinidis, N; Kopeliansky, R; Koperny, S; Köpke, L; Kopp, A K; Korcyl, K; Kordas, K; Korn, A; Korol, A; Korolkov, I; Korolkova, E V; Korotkov, V A; Kortner, O; Kortner, S; Kostyukhin, V V; Kotov, S; Kotov, V M; Kotwal, A; Kourkoumelis, C; Kouskoura, V; Koutsman, A; Kowalewski, R; Kowalski, T Z; Kozanecki, W; Kozhin, A S; Kral, V; Kramarenko, V A; Kramberger, G; Krasny, M W; Krasznahorkay, A; Kraus, J K; Kravchenko, A; Kreiss, S; Krejci, F; Kretzschmar, J; Kreutzfeldt, K; Krieger, N; Krieger, P; Kroeninger, K; Kroha, H; Kroll, J; Kroseberg, J; Krstic, J; Kruchonak, U; Krüger, H; Kruker, T; Krumnack, N; Krumshteyn, Z V; Kruse, M K; Kubota, T; Kuday, S; Kuehn, S; Kugel, A; Kuhl, T; Kukhtin, V; Kulchitsky, Y; Kuleshov, S; Kuna, M; Kunkle, J; Kupco, A; Kurashige, H; Kurata, M; Kurochkin, Y A; Kus, V; Kuwertz, E S; Kuze, M; Kvita, J; Kwee, R; La Rosa, A; La Rotonda, L; Labarga, L; Lablak, S; Lacasta, C; Lacava, F; Lacey, J; Lacker, H; Lacour, D; Lacuesta, V R; Ladygin, E; Lafaye, R; Laforge, B; Lagouri, T; Lai, S; Laisne, E; Lambourne, L; Lampen, C L; Lampl, W; Lançon, E; Landgraf, U; Landon, M P J; Lang, V S; Lange, C; Lankford, A J; Lanni, F; Lantzsch, K; Lanza, A; Laplace, S; Lapoire, C; Laporte, J F; Lari, T; Larner, A; Lassnig, M; Laurelli, P; Lavorini, V; Lavrijsen, W; Laycock, P; Le Dortz, O; Le Guirriec, E; Le Menedeu, E; LeCompte, T; Ledroit-Guillon, F; Lee, H; Lee, J S H; Lee, S C; Lee, L; Lefebvre, M; Legendre, M; Legger, F; Leggett, C; Lehmacher, M; Lehmann Miotto, G; Leister, A G; Leite, M A L; Leitner, R; Lellouch, D; Lemmer, B; Lendermann, V; Leney, K J C; Lenz, T; Lenzen, G; Lenzi, B; Leonhardt, K; Leontsinis, S; Lepold, F; Leroy, C; Lessard, J-R; Lester, C G; Lester, C M; Levêque, J; Levin, D; Levinson, L J; Lewis, A; Lewis, G H; Leyko, A M; Leyton, M; Li, B; Li, B; Li, H; Li, H L; Li, S; Li, X; Liang, Z; Liao, H; Liberti, B; Lichard, P; Lie, K; Liebal, J; Liebig, W; Limbach, C; Limosani, A; Limper, M; Lin, S C; Linde, F; Linnemann, J T; Lipeles, E; Lipniacka, A; Lisovyi, M; Liss, T M; Lissauer, D; Lister, A; Litke, A M; Liu, D; Liu, J B; Liu, L; Liu, M; Liu, Y; Livan, M; Livermore, S S A; Lleres, A; Llorente Merino, J; Lloyd, S L; Lo Sterzo, F; Lobodzinska, E; Loch, P; Lockman, W S; Loddenkoetter, T; Loebinger, F K; Loevschall-Jensen, A E; Loginov, A; Loh, C W; Lohse, T; Lohwasser, K; Lokajicek, M; Lombardo, V P; Long, R E; Lopes, L; Lopez Mateos, D; Lorenz, J; Lorenzo Martinez, N; Losada, M; Loscutoff, P; Losty, M J; Lou, X; Lounis, A; Loureiro, K F; Love, J; Love, P A; Lowe, A J; Lu, F; Lubatti, H J; Luci, C; Lucotte, A; Ludwig, D; Ludwig, I; Ludwig, J; Luehring, F; Lukas, W; Luminari, L; Lund, E; Lundberg, B; Lundberg, J; Lundberg, O; Lund-Jensen, B; Lundquist, J; Lungwitz, M; Lynn, D; Lysak, R; Lytken, E; Ma, H; Ma, L L; Maccarrone, G; Macchiolo, A; Maček, B; Machado Miguens, J; Macina, D; Mackeprang, R; Madar, R; Madaras, R J; Maddocks, H J; Mader, W F; Madsen, A; Maeno, M; Maeno, T; Magnoni, L; Magradze, E; Mahboubi, K; Mahlstedt, J; Mahmoud, S; Mahout, G; Maiani, C; Maidantchik, C; Maio, A; Majewski, S; Makida, Y; Makovec, N; Mal, P; Malaescu, B; Malecki, Pa; Malecki, P; Maleev, V P; Malek, F; Mallik, U; Malon, D; Malone, C; Maltezos, S; Malyshev, V; Malyukov, S; Mamuzic, J; Manabe, A; Mandelli, L; Mandić, I; Mandrysch, R; Maneira, J; Manfredini, A; Manhaes de Andrade Filho, L; Manjarres Ramos, J A; Mann, A; Manning, P M; Manousakis-Katsikakis, A; Mansoulie, B; Mantifel, R; Mapelli, A; Mapelli, L; March, L; Marchand, J F; Marchese, F; Marchiori, G; Marcisovsky, M; Marino, C P; Marroquim, F; Marshall, Z; Marti, L F; Marti-Garcia, S; Martin, B; Martin, B; Martin, J P; Martin, T A; Martin, V J; Martin Dit Latour, B; Martinez, H; Martinez, M; Martinez Outschoorn, V; Martin-Haugh, S; Martyniuk, A C; Marx, M; Marzano, F; Marzin, A; Masetti, L; Mashimo, T; Mashinistov, R; Masik, J; Maslennikov, A L; Massa, I; Massol, N; Mastrandrea, P; Mastroberardino, A; Masubuchi, T; Matsunaga, H; Matsushita, T; Mättig, P; Mättig, S; Mattravers, C; Maurer, J; Maxfield, S J; Maximov, D A; Mazini, R; Mazur, M; Mazzaferro, L; Mazzanti, M; Mc Donald, J; Mc Kee, S P; McCarn, A; McCarthy, R L; McCarthy, T G; McCubbin, N A; McFarlane, K W; Mcfayden, J A; Mchedlidze, G; Mclaughlan, T; McMahon, S J; McPherson, R A; Meade, A; Mechnich, J; Mechtel, M; Medinnis, M; Meehan, S; Meera-Lebbai, R; Meguro, T; Mehlhase, S; Mehta, A; Meier, K; Meineck, C; Meirose, B; Melachrinos, C; Mellado Garcia, B R; Meloni, F; Mendoza Navas, L; Meng, Z; Mengarelli, A; Menke, S; Meoni, E; Mercurio, K M; Meric, N; Mermod, P; Merola, L; Meroni, C; Merritt, F S; Merritt, H; Messina, A; Metcalfe, J; Mete, A S; Meyer, C; Meyer, C; Meyer, J-P; Meyer, J; Meyer, J; Michal, S; Micu, L; Middleton, R P; Migas, S; Mijović, L; Mikenberg, G; Mikestikova, M; Mikuž, M; Miller, D W; Miller, R J; Mills, W J; Mills, C; Milov, A; Milstead, D A; Milstein, D; Minaenko, A A; Miñano Moya, M; Minashvili, I A; Mincer, A I; Mindur, B; Mineev, M; Ming, Y; Mir, L M; Mirabelli, G; Mitrevski, J; Mitsou, V A; Mitsui, S; Miyagawa, P S; Mjörnmark, J U; Moa, T; Moeller, V; Mohapatra, S; Mohr, W; Moles-Valls, R; Molfetas, A; Mönig, K; Monini, C; Monk, J; Monnier, E; Montejo Berlingen, J; Monticelli, F; Monzani, S; Moore, R W; Mora Herrera, C; Moraes, A; Morange, N; Morel, J; Moreno, D; Moreno Llácer, M; Morettini, P; Morgenstern, M; Morii, M; Morley, A K; Mornacchi, G; Morris, J D; Morvaj, L; Möser, N; Moser, H G; Mosidze, M; Moss, J; Mount, R; Mountricha, E; Mouraviev, S V; Moyse, E J W; Mueller, F; Mueller, J; Mueller, K; Mueller, T; Muenstermann, D; Müller, T A; Munwes, Y; Murray, W J; Mussche, I; Musto, E; Myagkov, A G; Myska, M; Nackenhorst, O; Nadal, J; Nagai, K; Nagai, R; Nagai, Y; Nagano, K; Nagarkar, A; Nagasaka, Y; Nagel, M; Nairz, A M; Nakahama, Y; Nakamura, K; Nakamura, T; Nakano, I; Namasivayam, H; Nanava, G; Napier, A; Narayan, R; Nash, M; Nattermann, T; Naumann, T; Navarro, G; Neal, H A; Nechaeva, P Yu; Neep, T J; Negri, A; Negri, G; Negrini, M; Nektarijevic, S; Nelson, A; Nelson, T K; Nemecek, S; Nemethy, P; Nepomuceno, A A; Nessi, M; Neubauer, M S; Neumann, M; Neusiedl, A; Neves, R M; Nevski, P; Newcomer, F M; Newman, P R; Nguyen, D H; Nguyen Thi Hong, V; Nickerson, R B; Nicolaidou, R; Nicquevert, B; Niedercorn, F; Nielsen, J; Nikiforou, N; Nikiforov, A; Nikolaenko, V; Nikolic-Audit, I; Nikolics, K; Nikolopoulos, K; Nilsen, H; Nilsson, P; Ninomiya, Y; Nisati, A; Nisius, R; Nobe, T; Nodulman, L; Nomachi, M; Nomidis, I; Norberg, S; Nordberg, M; Novakova, J; Nozaki, M; Nozka, L; Nuncio-Quiroz, A-E; Nunes Hanninger, G; Nunnemann, T; Nurse, E; O'Brien, B J; O'Neil, D C; O'Shea, V; Oakes, L B; Oakham, F G; Oberlack, H; Ocariz, J; Ochi, A; Ochoa, M I; Oda, S; Odaka, S; Odier, J; Ogren, H; Oh, A; Oh, S H; Ohm, C C; Ohshima, T; Okamura, W; Okawa, H; Okumura, Y; Okuyama, T; Olariu, A; Olchevski, A G; Olivares Pino, S A; Oliveira, M; Oliveira Damazio, D; Oliver Garcia, E; Olivito, D; Olszewski, A; Olszowska, J; Onofre, A; Onyisi, P U E; Oram, C J; Oreglia, M J; Oren, Y; Orestano, D; Orlando, N; Oropeza Barrera, C; Orr, R S; Osculati, B; Ospanov, R; Osuna, C; Otero Y Garzon, G; Ottersbach, J P; Ouchrif, M; Ouellette, E A; Ould-Saada, F; Ouraou, A; Ouyang, Q; Ovcharova, A; Owen, M; Owen, S; Ozcan, V E; Ozturk, N; Pacheco Pages, A; Padilla Aranda, C; Pagan Griso, S; Paganis, E; Pahl, C; Paige, F; Pais, P; Pajchel, K; Palacino, G; Paleari, C P; Palestini, S; Pallin, D; Palma, A; Palmer, J D; Pan, Y B; Panagiotopoulou, E; Panduro Vazquez, J G; Pani, P; Panikashvili, N; Panitkin, S; Pantea, D; Papadelis, A; Papadopoulou, Th D; Paramonov, A; Paredes Hernandez, D; Park, W; Parker, M A; Parodi, F; Parsons, J A; Parzefall, U; Pashapour, S; Pasqualucci, E; Passaggio, S; Passeri, A; Pastore, F; Pastore, Fr; Pásztor, G; Pataraia, S; Patel, N D; Pater, J R; Patricelli, S; Pauly, T; Pearce, J; Pedersen, M; Pedraza Lopez, S; Pedraza Morales, M I; Peleganchuk, S V; Pelikan, D; Peng, H; Penning, B; Penson, A; Penwell, J; Perez Cavalcanti, T; Perez Codina, E; Pérez García-Estañ, M T; Perez Reale, V; Perini, L; Pernegger, H; Perrino, R; Perrodo, P; Peshekhonov, V D; Peters, K; Peters, R F Y; Petersen, B A; Petersen, J; Petersen, T C; Petit, E; Petridis, A; Petridou, C; Petrolo, E; Petrucci, F; Petschull, D; Petteni, M; Pezoa, R; Phan, A; Phillips, P W; Piacquadio, G; Pianori, E; Picazio, A; Piccaro, E; Piccinini, M; Piec, S M; Piegaia, R; Pignotti, D T; Pilcher, J E; Pilkington, A D; Pina, J; Pinamonti, M; Pinder, A; Pinfold, J L; Pingel, A; Pinto, B; Pizio, C; Pleier, M-A; Pleskot, V; Plotnikova, E; Plucinski, P; Poblaguev, A; Poddar, S; Podlyski, F; Poettgen, R; Poggioli, L; Pohl, D; Pohl, M; Polesello, G; Policicchio, A; Polifka, R; Polini, A; Poll, J; Polychronakos, V; Pomeroy, D; Pommès, K; Pontecorvo, L; Pope, B G; Popeneciu, G A; Popovic, D S; Poppleton, A; Portell Bueso, X; Pospelov, G E; Pospisil, S; Potrap, I N; Potter, C J; Potter, C T; Poulard, G; Poveda, J; Pozdnyakov, V; Prabhu, R; Pralavorio, P; Pranko, A; Prasad, S; Pravahan, R; Prell, S; Pretzl, K; Price, D; Price, J; Price, L E; Prieur, D; Primavera, M; Proissl, M; Prokofiev, K; Prokoshin, F; Protopapadaki, E; Protopopescu, S; Proudfoot, J; Prudent, X; Przybycien, M; Przysiezniak, H; Psoroulas, S; Ptacek, E; Pueschel, E; Puldon, D; Purohit, M; Puzo, P; Pylypchenko, Y; Qian, J; Quadt, A; Quarrie, D R; Quayle, W B; Quilty, D; Raas, M; Radeka, V; Radescu, V; Radloff, P; Ragusa, F; Rahal, G; Rahimi, A M; Rajagopalan, S; Rammensee, M; Rammes, M; Randle-Conde, A S; Randrianarivony, K; Rangel-Smith, C; Rao, K; Rauscher, F; Rave, T C; Ravenscroft, T; Raymond, M; Read, A L; Rebuzzi, D M; Redelbach, A; Redlinger, G; Reece, R; Reeves, K; Reinsch, A; Reisinger, I; Relich, M; Rembser, C; Ren, Z L; Renaud, A; Rescigno, M; Resconi, S; Resende, B; Reznicek, P; Rezvani, R; Richter, R; Richter-Was, E; Ridel, M; Rieck, P; Rijssenbeek, M; Rimoldi, A; Rinaldi, L; Rios, R R; Ritsch, E; Riu, I; Rivoltella, G; Rizatdinova, F; Rizvi, E; Robertson, S H; Robichaud-Veronneau, A; Robinson, D; Robinson, J E M; Robson, A; Rocha de Lima, J G; Roda, C; Roda Dos Santos, D; Roe, A; Roe, S; Røhne, O; Rolli, S; Romaniouk, A; Romano, M; Romeo, G; Romero Adam, E; Rompotis, N; Roos, L; Ros, E; Rosati, S; Rosbach, K; Rose, A; Rose, M; Rosenbaum, G A; Rosendahl, P L; Rosenthal, O; Rosselet, L; Rossetti, V; Rossi, E; Rossi, L P; Rotaru, M; Roth, I; Rothberg, J; Rousseau, D; Royon, C R; Rozanov, A; Rozen, Y; Ruan, X; Rubbo, F; Rubinskiy, I; Ruckstuhl, N; Rud, V I; Rudolph, C; Rudolph, M S; Rühr, F; Ruiz-Martinez, A; Rumyantsev, L; Rurikova, Z; Rusakovich, N A; Ruschke, A; Rutherfoord, J P; Ruthmann, N; Ruzicka, P; Ryabov, Y F; Rybar, M; Rybkin, G; Ryder, N C; Saavedra, A F; Sadeh, I; Sadrozinski, H F-W; Sadykov, R; Safai Tehrani, F; Sakamoto, H; Salamanna, G; Salamon, A; Saleem, M; Salek, D; Salihagic, D; Salnikov, A; Salt, J; Salvachua Ferrando, B M; Salvatore, D; Salvatore, F; Salvucci, A; Salzburger, A; Sampsonidis, D; Sanchez, A; Sánchez, J; Sanchez Martinez, V; Sandaker, H; Sander, H G; Sanders, M P; Sandhoff, M; Sandoval, T; Sandoval, C; Sandstroem, R; Sankey, D P C; Sansoni, A; Santamarina Rios, C; Santoni, C; Santonico, R; Santos, H; Santoyo Castillo, I; Sapp, K; Saraiva, J G; Sarangi, T; Sarkisyan-Grinbaum, E; Sarrazin, B; Sarri, F; Sartisohn, G; Sasaki, O; Sasaki, Y; Sasao, N; Satsounkevitch, I; Sauvage, G; Sauvan, E; Sauvan, J B; Savard, P; Savinov, V; Savu, D O; Sawyer, L; Saxon, D H; Saxon, J; Sbarra, C; Sbrizzi, A; Scannicchio, D A; Scarcella, M; Schaarschmidt, J; Schacht, P; Schaefer, D; Schaelicke, A; Schaepe, S; Schaetzel, S; Schäfer, U; Schaffer, A C; Schaile, D; Schamberger, R D; Scharf, V; Schegelsky, V A; Scheirich, D; Schernau, M; Scherzer, M I; Schiavi, C; Schieck, J; Schillo, C; Schioppa, M; Schlenker, S; Schmidt, E; Schmieden, K; Schmitt, C; Schmitt, C; Schmitt, S; Schneider, B; Schnellbach, Y J; Schnoor, U; Schoeffel, L; Schoening, A; Schorlemmer, A L S; Schott, M; Schouten, D; Schovancova, J; Schram, M; Schroeder, C; Schroer, N; Schultens, M J; Schultes, J; Schultz-Coulon, H-C; Schulz, H; Schumacher, M; Schumm, B A; Schune, Ph; Schwartzman, A; Schwegler, Ph; Schwemling, Ph; Schwienhorst, R; Schwindling, J; Schwindt, T; Schwoerer, M; Sciacca, F G; Scifo, E; Sciolla, G; Scott, W G; Searcy, J; Sedov, G; Sedykh, E; Seidel, S C; Seiden, A; Seifert, F; Seixas, J M; Sekhniaidze, G; Sekula, S J; Selbach, K E; Seliverstov, D M; Sellden, B; Sellers, G; Seman, M; Semprini-Cesari, N; Serfon, C; Serin, L; Serkin, L; Serre, T; Seuster, R; Severini, H; Sfyrla, A; Shabalina, E; Shamim, M; Shan, L Y; Shank, J T; Shao, Q T; Shapiro, M; Shatalov, P B; Shaw, K; Sherwood, P; Shimizu, S; Shimojima, M; Shin, T; Shiyakova, M; Shmeleva, A; Shochet, M J; Short, D; Shrestha, S; Shulga, E; Shupe, M A; Sicho, P; Sidoti, A; Siegert, F; Sijacki, Dj; Silbert, O; Silva, J; Silver, Y; Silverstein, D; Silverstein, S B; Simak, V; Simard, O; Simic, Lj; Simion, S; Simioni, E; Simmons, B; Simoniello, R; Simonyan, M; Sinervo, P; Sinev, N B; Sipica, V; Siragusa, G; Sircar, A; Sisakyan, A N; Sivoklokov, S Yu; Sjölin, J; Sjursen, T B; Skinnari, L A; Skottowe, H P; Skovpen, K; Skubic, P; Slater, M; Slavicek, T; Sliwa, K; Smakhtin, V; Smart, B H; Smestad, L; Smirnov, S Yu; Smirnov, Y; Smirnova, L N; Smirnova, O; Smith, B C; Smith, K M; Smizanska, M; Smolek, K; Snesarev, A A; Snidero, G; Snow, S W; Snow, J; Snyder, S; Sobie, R; Sodomka, J; Soffer, A; Soh, D A; Solans, C A; Solar, M; Solc, J; Soldatov, E Yu; Soldevila, U; Solfaroli Camillocci, E; Solodkov, A A; Solovyanov, O V; Solovyev, V; Soni, N; Sood, A; Sopko, V; Sopko, B; Sosebee, M; Soualah, R; Soueid, P; Soukharev, A; South, D; Spagnolo, S; Spanò, F; Spighi, R; Spigo, G; Spiwoks, R; Spousta, M; Spreitzer, T; Spurlock, B; St Denis, R D; Stahlman, J; Stamen, R; Stanecka, E; Stanek, R W; Stanescu, C; Stanescu-Bellu, M; Stanitzki, M M; Stapnes, S; Starchenko, E A; Stark, J; Staroba, P; Starovoitov, P; Staszewski, R; Staude, A; Stavina, P; Steele, G; Steinbach, P; Steinberg, P; Stekl, I; Stelzer, B; Stelzer, H J; Stelzer-Chilton, O; Stenzel, H; Stern, S; Stewart, G A; Stillings, J A; Stockton, M C; Stoebe, M; Stoerig, K; Stoicea, G; Stonjek, S; Strachota, P; Stradling, A R; Straessner, A; Strandberg, J; Strandberg, S; Strandlie, A; Strang, M; Strauss, E; Strauss, M; Strizenec, P; Ströhmer, R; Strom, D M; Strong, J A; Stroynowski, R; Stugu, B; Stumer, I; Stupak, J; Sturm, P; Styles, N A; Su, D; Subramania, Hs; Subramaniam, R; Succurro, A; Sugaya, Y; Suhr, C; Suk, M; Sulin, V V; Sultansoy, S; Sumida, T; Sun, X; Sundermann, J E; Suruliz, K; Susinno, G; Sutton, M R; Suzuki, Y; Suzuki, Y; Svatos, M; Swedish, S; Swiatlowski, M; Sykora, I; Sykora, T; Ta, D; Tackmann, K; Taffard, A; Tafirout, R; Taiblum, N; Takahashi, Y; Takai, H; Takashima, R; Takeda, H; Takeshita, T; Takubo, Y; Talby, M; Talyshev, A; Tam, J Y C; Tamsett, M C; Tan, K G; Tanaka, J; Tanaka, R; Tanaka, S; Tanaka, S; Tanasijczuk, A J; Tani, K; Tannoury, N; Tapprogge, S; Tardif, D; Tarem, S; Tarrade, F; Tartarelli, G F; Tas, P; Tasevsky, M; Tassi, E; Tayalati, Y; Taylor, C; Taylor, F E; Taylor, G N; Taylor, W; Teinturier, M; Teischinger, F A; Teixeira Dias Castanheira, M; Teixeira-Dias, P; Temming, K K; Ten Kate, H; Teng, P K; Terada, S; Terashi, K; Terron, J; Testa, M; Teuscher, R J; Therhaag, J; Theveneaux-Pelzer, T; Thoma, S; Thomas, J P; Thompson, E N; Thompson, P D; Thompson, P D; Thompson, A S; Thomsen, L A; Thomson, E; Thomson, M; Thong, W M; Thun, R P; Tian, F; Tibbetts, M J; Tic, T; Tikhomirov, V O; Tikhonov, Y A; Timoshenko, S; Tiouchichine, E; Tipton, P; Tisserant, S; Todorov, T; Todorova-Nova, S; Toggerson, B; Tojo, J; Tokár, S; Tokushuku, K; Tollefson, K; Tomlinson, L; Tomoto, M; Tompkins, L; Toms, K; Tonoyan, A; Topfel, C; Topilin, N D; Torrence, E; Torres, H; Torró Pastor, E; Toth, J; Touchard, F; Tovey, D R; Tran, H L; Trefzger, T; Tremblet, L; Tricoli, A; Trigger, I M; Trincaz-Duvoid, S; Tripiana, M F; Triplett, N; Trischuk, W; Trocmé, B; Troncon, C; Trottier-McDonald, M; Trovatelli, M; True, P; Trzebinski, M; Trzupek, A; Tsarouchas, C; Tseng, J C-L; Tsiakiris, M; Tsiareshka, P V; Tsionou, D; Tsipolitis, G; Tsiskaridze, S; Tsiskaridze, V; Tskhadadze, E G; Tsukerman, I I; Tsulaia, V; Tsung, J-W; Tsuno, S; Tsybychev, D; Tua, A; Tudorache, A; Tudorache, V; Tuggle, J M; Turala, M; Turecek, D; Turk Cakir, I; Turra, R; Tuts, P M; Tykhonov, A; Tylmad, M; Tyndel, M; Tzanakos, G; Uchida, K; Ueda, I; Ueno, R; Ughetto, M; Ugland, M; Uhlenbrock, M; Ukegawa, F; Unal, G; Undrus, A; Unel, G; Ungaro, F C; Unno, Y; Urbaniec, D; Urquijo, P; Usai, G; Vacavant, L; Vacek, V; Vachon, B; Vahsen, S; Valencic, N; Valentinetti, S; Valero, A; Valery, L; Valkar, S; Valladolid Gallego, E; Vallecorsa, S; Valls Ferrer, J A; Van Berg, R; Van Der Deijl, P C; van der Geer, R; van der Graaf, H; Van Der Leeuw, R; van der Poel, E; van der Ster, D; van Eldik, N; van Gemmeren, P; Van Nieuwkoop, J; van Vulpen, I; Vanadia, M; Vandelli, W; Vaniachine, A; Vankov, P; Vannucci, F; Vari, R; Varnes, E W; Varol, T; Varouchas, D; Vartapetian, A; Varvell, K E; Vassilakopoulos, V I; Vazeille, F; Vazquez Schroeder, T; Veloso, F; Veneziano, S; Ventura, A; Ventura, D; Venturi, M; Venturi, N; Vercesi, V; Verducci, M; Verkerke, W; Vermeulen, J C; Vest, A; Vetterli, M C; Vichou, I; Vickey, T; Vickey Boeriu, O E; Viehhauser, G H A; Viel, S; Villa, M; Villaplana Perez, M; Vilucchi, E; Vincter, M G; Vinek, E; Vinogradov, V B; Virzi, J; Vitells, O; Viti, M; Vivarelli, I; Vives Vaque, F; Vlachos, S; Vladoiu, D; Vlasak, M; Vogel, A; Vokac, P; Volpi, G; Volpi, M; Volpini, G; von der Schmitt, H; von Radziewski, H; von Toerne, E; Vorobel, V; Vorwerk, V; Vos, M; Voss, R; Vossebeld, J H; Vranjes, N; Vranjes Milosavljevic, M; Vrba, V; Vreeswijk, M; Vu Anh, T; Vuillermet, R; Vukotic, I; Vykydal, Z; Wagner, W; Wagner, P; Wahlen, H; Wahrmund, S; Wakabayashi, J; Walch, S; Walder, J; Walker, R; Walkowiak, W; Wall, R; Waller, P; Walsh, B; Wang, C; Wang, H; Wang, H; Wang, J; Wang, J; Wang, K; Wang, R; Wang, S M; Wang, T; Wang, X; Warburton, A; Ward, C P; Wardrope, D R; Warsinsky, M; Washbrook, A; Wasicki, C; Watanabe, I; Watkins, P M; Watson, A T; Watson, I J; Watson, M F; Watts, G; Watts, S; Waugh, A T; Waugh, B M; Weber, M S; Webster, J S; Weidberg, A R; Weigell, P; Weingarten, J; Weiser, C; Wells, P S; Wenaus, T; Wendland, D; Weng, Z; Wengler, T; Wenig, S; Wermes, N; Werner, M; Werner, P; Werth, M; Wessels, M; Wetter, J; Weydert, C; Whalen, K; White, A; White, M J; White, S; Whitehead, S R; Whiteson, D; Whittington, D; Wicke, D; Wickens, F J; Wiedenmann, W; Wielers, M; Wienemann, P; Wiglesworth, C; Wiik-Fuchs, L A M; Wijeratne, P A; Wildauer, A; Wildt, M A; Wilhelm, I; Wilkens, H G; Will, J Z; Williams, E; Williams, H H; Williams, S; Willis, W; Willocq, S; Wilson, J A; Wilson, M G; Wilson, A; Wingerter-Seez, I; Winkelmann, S; Winklmeier, F; Wittgen, M; Wittig, T; Wittkowski, J; Wollstadt, S J; Wolter, M W; Wolters, H; Wong, W C; Wooden, G; Wosiek, B K; Wotschack, J; Woudstra, M J; Wozniak, K W; Wraight, K; Wright, M; Wrona, B; Wu, S L; Wu, X; Wu, Y; Wulf, E; Wynne, B M; Xella, S; Xiao, M; Xie, S; Xu, C; Xu, D; Xu, L; Yabsley, B; Yacoob, S; Yamada, M; Yamaguchi, H; Yamaguchi, Y; Yamamoto, A; Yamamoto, K; Yamamoto, S; Yamamura, T; Yamanaka, T; Yamauchi, K; Yamazaki, T; Yamazaki, Y; Yan, Z; Yang, H; Yang, H; Yang, U K; Yang, Y; Yang, Z; Yanush, S; Yao, L; Yasu, Y; Yatsenko, E; Ye, J; Ye, S; Yen, A L; Yilmaz, M; Yoosoofmiya, R; Yorita, K; Yoshida, R; Yoshihara, K; Young, C; Young, C J S; Youssef, S; Yu, D; Yu, D R; Yu, J; Yu, J; Yuan, L; Yurkewicz, A; Zabinski, B; Zaidan, R; Zaitsev, A M; Zambito, S; Zanello, L; Zanzi, D; Zaytsev, A; Zeitnitz, C; Zeman, M; Zemla, A; Zenin, O; Ženiš, T; Zerwas, D; Zevi Della Porta, G; Zhang, D; Zhang, H; Zhang, J; Zhang, L; Zhang, X; Zhang, Z; Zhao, L; Zhao, Z; Zhemchugov, A; Zhong, J; Zhou, B; Zhou, N; Zhou, Y; Zhu, C G; Zhu, H; Zhu, J; Zhu, Y; Zhuang, X; Zhuravlov, V; Zibell, A; Zieminska, D; Zimin, N I; Zimmermann, R; Zimmermann, S; Zimmermann, S; Zinonos, Z; Ziolkowski, M; Zitoun, R; Živković, L; Zmouchko, V V; Zobernig, G; Zoccoli, A; Zur Nedden, M; Zutshi, V; Zwalinski, L

A measurement of splitting scales, as defined by the k T clustering algorithm, is presented for final states containing a W boson produced in proton-proton collisions at a centre-of-mass energy of 7 TeV. The measurement is based on the full 2010 data sample corresponding to an integrated luminosity of 36 pb -1 which was collected using the ATLAS detector at the CERN Large Hadron Collider. Cluster splitting scales are measured in events containing W bosons decaying to electrons or muons. The measurement comprises the four hardest splitting scales in a k T cluster sequence of the hadronic activity accompanying the W boson, and ratios of these splitting scales. Backgrounds such as multi-jet and top-quark-pair production are subtracted and the results are corrected for detector effects. Predictions from various Monte Carlo event generators at particle level are compared to the data. Overall, reasonable agreement is found with all generators, but larger deviations between the predictions and the data are evident in the soft regions of the splitting scales.

The Efficiency of Split Panel Designs in an Analysis of Variance Model

PubMed Central

Wang, Wei-Guo; Liu, Hai-Jun

2016-01-01

We consider split panel design efficiency in analysis of variance models, that is, the determination of the cross-sections series optimal proportion in all samples, to minimize parametric best linear unbiased estimators of linear combination variances. An orthogonal matrix is constructed to obtain manageable expression of variances. On this basis, we derive a theorem for analyzing split panel design efficiency irrespective of interest and budget parameters. Additionally, relative estimator efficiency based on the split panel to an estimator based on a pure panel or a pure cross-section is present. The analysis shows that the gains from split panel can be quite substantial. We further consider the efficiency of split panel design, given a budget, and transform it to a constrained nonlinear integer programming. Specifically, an efficient algorithm is designed to solve the constrained nonlinear integer programming. Moreover, we combine one at time designs and factorial designs to illustrate the algorithm’s efficiency with an empirical example concerning monthly consumer expenditure on food in 1985, in the Netherlands, and the efficient ranges of the algorithm parameters are given to ensure a good solution. PMID:27163447

Density functional calculations of the Mössbauer parameters in hexagonal ferrite SrFe12O19

NASA Astrophysics Data System (ADS)

Ikeno, Hidekazu

2018-03-01

Mössbauer parameters in a magnetoplumbite-type hexagonal ferrite, SrFe12O19, are computed using the all-electron band structure calculation based on the density functional theory. The theoretical isomer shift and quadrupole splitting are consistent with experimentally obtained values. The absolute values of hyperfine splitting parameters are found to be underestimated, but the relative scale can be reproduced. The present results validate the site-dependence of Mössbauer parameters obtained by analyzing experimental spectra of hexagonal ferrites. The results also show the usefulness of theoretical calculations for increasing the reliability of interpretation of the Mössbauer spectra.

Precision ESR measurements of transverse anisotropy in the single-molecule magnet Ni4

NASA Astrophysics Data System (ADS)

Collett, Charles A.; Allão Cassaro, Rafael A.; Friedman, Jonathan R.

2016-12-01

We present a method for precisely measuring the tunnel splitting in single-molecule magnets (SMMs) using electron-spin resonance, and use these measurements to precisely and independently determine the underlying transverse anisotropy parameter, given a certain class of transitions. By diluting samples of the SMM Ni4 via cocrystallization in a diamagnetic isostructural analog we obtain markedly narrower resonance peaks than are observed in undiluted samples. Using custom loop-gap resonators we measure the transitions at several frequencies, allowing a precise determination of the tunnel splitting. Because the transition under investigation occurs at zero field, and arises due to a first-order perturbation from the transverse anisotropy, we can determine the magnitude of this anisotropy independent of any other Hamiltonian parameters. This method can be applied to other SMMs with tunnel splittings arising from first-order transverse anisotropy perturbations.

Split Flow Online Solid-Phase Extraction Coupled with Inductively Coupled Plasma Mass Spectrometry System for One-Shot Data Acquisition of Quantification and Recovery Efficiency.

PubMed

Furukawa, Makoto; Takagai, Yoshitaka

2016-10-04

Online solid-phase extraction (SPE) coupled with inductively coupled plasma mass spectrometry (ICPMS) is a useful tool in automatic sequential analysis. However, it cannot simultaneously quantify the analytical targets and their recovery percentages (R%) in one-shot samples. We propose a system that simultaneously acquires both data in a single sample injection. The main flowline of the online solid-phase extraction is divided into main and split flows. The split flow line (i.e., bypass line), which circumvents the SPE column, was placed on the main flow line. Under program-controlled switching of the automatic valve, the ICPMS sequentially measures the targets in a sample before and after column preconcentration and determines the target concentrations and the R% on the SPE column. This paper describes the system development and two demonstrations to exhibit the analytical significance, i.e., the ultratrace amounts of radioactive strontium ( 90 Sr) using commercial Sr-trap resin and multielement adsorbability on the SPE column. This system is applicable to other flow analyses and detectors in online solid phase extraction.

Effects of priming self-construals on self-evaluations: Cultural game player perspective.

PubMed

Kim, Jungsik; Song, Eugene; Takemoto, Timothy

2016-12-01

This study examined the validity of situational view on culture-specific behaviours focusing on self-evaluation. Two experiments with American students as samples were conducted to examine whether priming their self-construals would affect individuals' self-evaluation. In Experiment 1, the participants' self-evaluation was compared across different conditions of primed self-contruals. In Experiment 2, the participants were split into 2 groups based on their initial default self-consturals and, the self-evaluations were compared across the 2 groups after priming self-contruals. The results demonstrated that although the participants' self-evaluation was initially in accord with their default self-construal, it changed into accord with the primed self-construals. The findings supported the proposed cultural game player view. Implications on situational view of self-evaluation are also discussed. © 2015 International Union of Psychological Science.

Automated cloud screening of AVHRR imagery using split-and-merge clustering

NASA Technical Reports Server (NTRS)

Gallaudet, Timothy C.; Simpson, James J.

1991-01-01

Previous methods to segment clouds from ocean in AVHRR imagery have shown varying degrees of success, with nighttime approaches being the most limited. An improved method of automatic image segmentation, the principal component transformation split-and-merge clustering (PCTSMC) algorithm, is presented and applied to cloud screening of both nighttime and daytime AVHRR data. The method combines spectral differencing, the principal component transformation, and split-and-merge clustering to sample objectively the natural classes in the data. This segmentation method is then augmented by supervised classification techniques to screen clouds from the imagery. Comparisons with other nighttime methods demonstrate its improved capability in this application. The sensitivity of the method to clustering parameters is presented; the results show that the method is insensitive to the split-and-merge thresholds.

Cross validation of gas chromatography-flame photometric detection and gas chromatography-mass spectrometry methods for measuring dialkylphosphate metabolites of organophosphate pesticides in human urine.

PubMed

Prapamontol, Tippawan; Sutan, Kunrunya; Laoyang, Sompong; Hongsibsong, Surat; Lee, Grace; Yano, Yukiko; Hunter, Ronald Elton; Ryan, P Barry; Barr, Dana Boyd; Panuwet, Parinya

2014-01-01

We report two analytical methods for the measurement of dialkylphosphate (DAP) metabolites of organophosphate pesticides in human urine. These methods were independently developed/modified and implemented in two separate laboratories and cross validated. The aim was to develop simple, cost effective, and reliable methods that could use available resources and sample matrices in Thailand and the United States. While several methods already exist, we found that direct application of these methods required modification of sample preparation and chromatographic conditions to render accurate, reliable data. The problems encountered with existing methods were attributable to urinary matrix interferences, and differences in the pH of urine samples and reagents used during the extraction and derivatization processes. Thus, we provide information on key parameters that require attention during method modification and execution that affect the ruggedness of the methods. The methods presented here employ gas chromatography (GC) coupled with either flame photometric detection (FPD) or electron impact ionization-mass spectrometry (EI-MS) with isotopic dilution quantification. The limits of detection were reported from 0.10ng/mL urine to 2.5ng/mL urine (for GC-FPD), while the limits of quantification were reported from 0.25ng/mL urine to 2.5ng/mL urine (for GC-MS), for all six common DAP metabolites (i.e., dimethylphosphate, dimethylthiophosphate, dimethyldithiophosphate, diethylphosphate, diethylthiophosphate, and diethyldithiophosphate). Each method showed a relative recovery range of 94-119% (for GC-FPD) and 92-103% (for GC-MS), and relative standard deviations (RSD) of less than 20%. Cross-validation was performed on the same set of urine samples (n=46) collected from pregnant women residing in the agricultural areas of northern Thailand. The results from split sample analysis from both laboratories agreed well for each metabolite, suggesting that each method can produce comparable data. In addition, results from analyses of specimens from the German External Quality Assessment Scheme (G-EQUAS) suggested that the GC-FPD method produced accurate results that can be reasonably compared to other studies. Copyright © 2013 Elsevier GmbH. All rights reserved.

A MEMS and agile optics-based dual-mode variable optical power splitter with no moving parts

NASA Astrophysics Data System (ADS)

Khwaja, Tariq S.; Suleman, Hamid; Reza, Syed Azer

2017-06-01

In this paper, we present a novel design of an optical power splitter. Owing to the inherent variable power split ratios that the proposed design delivers, it is ideal for use in communications, sensing and signal processing applications where variable power splitting is often quintessential. The proposed power splitter module is dual mode as it combines the use of a Micro-Electro-Mechanical Systems (MEMS) based Digital Micro-mirror Device (DMD) and an Electronically Controlled Tunable Lens (ECTL) to split the power of an input optical signal between two output ports - the designated port and the surplus port. The use of a reflective Digital Spatial Light Modulator (DSLM) such as the DMD provides a motion-free digital control of the split ratio between the two output ports. Although the digital step between two possible successive split ratios can be fairly minimal with the use of a high resolution DMD but it is a challenge to correctly ascertain the exact image pattern on the DMD to obtain any desired specific split ratio. To counter this challenge, we propose the synchronized use of a circular pattern on the DMD, which serves as a circular clear aperture with a tunable radius, and an ECTL. The radius of the circular pattern on the DMD provides a digital control of the split ratio between the two ports whereas the ECTL, depending on its controller, can provide either an analog or a digital control by altering the beam radius which is incident at the DMD circular pattern. The radius of the circular pattern on the DMD can be minimally changed by one micro-pixel thickness. Setting the radius of the circular pattern on the DMD to an appropriate value provides the closest "ball-park" split ratio whereas further tuning the ECTL aids in slightly altering from this digitally set value to obtain the exact desired split ratio in-between any two digitally-set successive split ratios that correspond to any clear aperture radius of the DMD pattern and its incremental minimal allowable change of one micropixel. We provide a detailed scheme to calculate the desired DMD aperture radius as well as the focal length setting of the ECTL to obtain any given split ratio. By setting tolerance limits on the split ratio, we also show that our method affords diversity by providing multiple possible solutions to achieve a desired optical power split ratio within the specified tolerances. We also demonstrate the validation of the proposed concept with initial experimental results and discussions. These experimental results show a repeatable splitter operation and the resulting power split ratios according to the theoretical predictions. With the experimental data, we also demonstrate the effectiveness of the method in obtaining any particular split ratio through different DMD and ECTL configurations with specific split ratio tolerance values.

How much is enough? Examining frequency criteria for NSSI disorder in adolescent inpatients.

PubMed

Muehlenkamp, Jennifer J; Brausch, Amy M; Washburn, Jason J

2017-06-01

To empirically evaluate the diagnostic relevance of the proposed Diagnostic and Statistical Manual of Mental Disorders (5th ed.; DSM-5 ; APA, 2013) Criterion-A frequency threshold for nonsuicidal self-injury (NSSI) disorder. Archival, de-identified, self-reported clinical assessment data from 746 adolescent psychiatric patients (Mage = 14.97; 88% female; 76% White) were used. The sample was randomly split into 2 unique samples for data analyses. Measures included assessments of NSSI, proposed DSM-5 NSSI-disorder criteria, psychopathology, dysfunction, distress, functional impairment, and suicidality. Discriminant-function analyses run with Sample A identified a significant differentiation of groups based on a frequency of NSSI at 25 or more days in the past year, Λ = .814, χ2(54) = 72.59, p < .05, canonical R2 = .36. This cutoff was replicated in the second sample. All patients were coded into 1 of 3 empirically derived NSSI-frequency cutoff groups: high (>25 days), moderate (5-24 days), and low (1-4 days) and compared. The high-NSSI group scored higher on most NSSI features, including DSM-5 -proposed Criterion-B and -C symptoms, depression, psychotic symptoms, substance abuse, borderline personality-disorder features, suicidal ideation, and suicide plans, than the moderate- and low-NSSI groups, who did not differ from each other on many of the variables. The currently proposed DSM-5 Criterion-A frequency threshold for NSSI disorder lacks validity and clinical utility. The field needs to consider raising the frequency threshold to ensure that a meaningful and valid set of diagnostic criteria are established, and to avoid overpathologizing individuals who infrequently engage in NSSI. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

The Counseling Competencies Scale: Validation and Refinement

ERIC Educational Resources Information Center

Lambie, Glenn W.; Mullen, Patrick R.; Swank, Jacqueline M.; Blount, Ashley

2018-01-01

Supervisors evaluated counselors-in-training at multiple points during their practicum experience using the Counseling Competencies Scale (CCS; N = 1,070). The CCS evaluations were randomly split to conduct exploratory factor analysis and confirmatory factor analysis, resulting in a 2-factor model (61.5% of the variance explained).

Revalidation of the Malay Version of the Edinburgh Postnatal Depression Scale (EPDS) Among Malay Postpartum Women Attending the Bakar Bata Health Center in Alor Setar, Kedah, North West Of Peninsular Malaysia

PubMed Central

Mahmud, Wan Mohd. Rushidi Wan; Awang, Amir; Mohamed, Mahmood Nazar

2003-01-01

Aim: To reevaluate the psychometric characteristics of the Malay version of the Edinburgh Postnatal Depression Scale among a sample of postpartum Malay women attending the Bakar Bata Health Center in Alor Setar, Kedah, North West of Peninsular Malaysia. Materials and methods: 64 women between 4 to 12 weeks postpartum were recruited for there validation study. They were given questionnaires on socio-demography, the 21-item Malay version of the Beck Depression Inventory II (BDI-II) and the 10-item Malay version of the Edinburgh Postnatal Depression Scale (EPDS). All the participants were later interviewed using the Hamilton Depression Rating Scale (HDRS-17) and the Composite International Diagnostic Interview (CIDI). All diagnoses were made based on the Tenth Edition of the International Classification of Diseases (ICD-10) Results: 9 women (14.1%) were diagnosed to have significant depression (7 mild depressive episodes and 2 moderate depressive episodes according to ICD-10). EPDS was found to have good internal consistency (Cronbach alpha =0.86) and split half reliability (Spearman split half coefficient = 0.83). The instrument also showed satisfactory discriminant and concurrent validity as evidenced by the statistically significant difference in EPDS scores between the depressed group and their non-depressed counterparts (Mann Whitney U test: 2 tailed p value < 0.01) and good correlations between the instrument and both the Malay version of BDI-II and the HRDS-17 (Spearman rank correlation coefficients of 0.78 and 0.88 respectively). At the 11/12 cut-off score the sensitivity of the EPDS is 100%, with a specificity of 98.18%, positive predictive value of 90%, negative predictive value of 100 % and misclassification rate of 1.56%. Conclusion: This study confirmed the reliability and validity of the Malay version of the Edinburgh Postnatal Depression Scale in identifying postpartum depression among recently delivered Malay women attending the Bata Bata Health Center in Alor Setar, Kedah, North West of Peninsular Malaysia. PMID:23386800

Validation of the Turkish version of the Centre for Epidemiologic Studies Depression Scale (CES-D) in patients with type 2 diabetes mellitus.

PubMed

Lehmann, Vicky; Makine, Ceylan; Karşıdağ, Cagatay; Kadıoğlu, Pinar; Karşıdağ, Kubilay; Pouwer, François

2011-07-26

Depression is a common co-morbid health problem in patients with diabetes that is underrecognised. Current international guidelines recommend screening for depression in patients with diabetes. Yet, few depression screening instruments have been validated for use in this particular group of patients. Aim of the present study was to investigate the psychometric properties of the Turkish version of the Centre for Epidemiologic Studies Depression Scale (CES-D) in patients with type 2 diabetes. A sample of 151 Turkish outpatients with type 2 diabetes completed the CES-D, the World Health Organization-Five Well-Being Index (WHO-5), and the Problem Areas in Diabetes scale (PAID). Explanatory factor analyses, various correlations and Cronbach's alpha were investigated to test the validity and reliability of the CES-D in Turkish diabetes outpatients. The original four-factor structure proposed by Radloff was not confirmed. Explanatory factor analyses revealed a two-factor structure representing two subscales: (1) depressed mood combined with somatic symptoms of depression and (2) positive affect. However, one item showed insufficient factor loadings. Cronbach's alpha of the total score was high (0.88), as were split-half coefficients (0.77-0.90). The correlation of the CES-D with the WHO-5 was the strongest (r = -0.70), and supported concurrent validity. The CES-D appears to be a valid measure for the assessment of depression in Turkish diabetes patients. Future studies should investigate its sensitivity and specificity as well as test-retest reliability.

[Utilization of Quality-of-life assessment Questionnaires for Intermittent Exotropia in China].

PubMed

Zhu, H; Xu, S; Leng, Z H; Fu, Z J; Xiao, Y H; Liu, H

2016-08-01

To evaluate the reliability and validity of Chinese version of Quality-of-life assessment Questionnaires for Intermittent Exotropia (CIXTQ). Cross-sectional study. The original English version of the IXTQ was translated into Chinese. The final Chinese version of the IXTQ (CIXTQ) consists of 3 parts: the 12-item child CIXTQ (for children ≥5 and<8 years old and ≥8 and<18 years old, respectively, to assess their health quality of life (HRQoL)), the 12-item proxy CIXTQ (for parents to assess children's HRQoL), and the 17-item parent CIXTQ (containing functional, psychosocial, and surgery subscales; for parents to assess their HRQoL). 175 IXT children and 151 control children along with one of their parents were recruited to answer the CIXTQ. Cronbach's α coefficient and split-half reliability were used to test the internal consistency reliability of the CIXTQ. Kappa coefficient was used to assess the test-retest reliability. Scale-level content validity index/average (S-CVI/Ave) was used to evaluate the content validity of the CIXTQ. Principal component analysis (PCA) was used to verify the construct validity of the parent CIXTQ. Comparison of different CIXTQ scores in IXT patients with controls was conducted by independent-samples t test to evaluate the discriminate validity of the CIXTQ. For all scales and subscales of the CIXTQ in different age groups, the Cronbach's α ranged from 0.804 to 0.963; the split-half reliability ranged from 0.658 to 0.963 and was higher than 0.7 except for the proxy CIXTQ for children aged ≥5 and<8 years old; the test-retest reliability ranged from 0.569 to 0.944. The S-CVI/Ave of the child, proxy and parent CIXTQ was 0.988, 0.988 and 0.966, respectively. Principal factors identified by PCA for the parent CIXTQ could be regrouped into the originally described 3 subscales which was functional, social psychology and surgery in different age groups. The mean scores of all the scales and subscales among IXT children and their parents (8.0±12.5-81.6 ±15.1) were significantly lower than these among control children and their parents (83.1±11.3-99.6±1.2) (t values range from -50.36 to -6.93, P<0.001). The CIXTQ are useful tools to evaluate the influence of IXT on HRQoL among Chinese children and their parents. (Chin J Ophthalmol, 2016, 52: 596-603).

MIP models and hybrid algorithms for simultaneous job splitting and scheduling on unrelated parallel machines.

PubMed

Eroglu, Duygu Yilmaz; Ozmutlu, H Cenk

2014-01-01

We developed mixed integer programming (MIP) models and hybrid genetic-local search algorithms for the scheduling problem of unrelated parallel machines with job sequence and machine-dependent setup times and with job splitting property. The first contribution of this paper is to introduce novel algorithms which make splitting and scheduling simultaneously with variable number of subjobs. We proposed simple chromosome structure which is constituted by random key numbers in hybrid genetic-local search algorithm (GAspLA). Random key numbers are used frequently in genetic algorithms, but it creates additional difficulty when hybrid factors in local search are implemented. We developed algorithms that satisfy the adaptation of results of local search into the genetic algorithms with minimum relocation operation of genes' random key numbers. This is the second contribution of the paper. The third contribution of this paper is three developed new MIP models which are making splitting and scheduling simultaneously. The fourth contribution of this paper is implementation of the GAspLAMIP. This implementation let us verify the optimality of GAspLA for the studied combinations. The proposed methods are tested on a set of problems taken from the literature and the results validate the effectiveness of the proposed algorithms.

Association between split selection instability and predictive error in survival trees.

PubMed

Radespiel-Tröger, M; Gefeller, O; Rabenstein, T; Hothorn, T

2006-01-01

To evaluate split selection instability in six survival tree algorithms and its relationship with predictive error by means of a bootstrap study. We study the following algorithms: logrank statistic with multivariate p-value adjustment without pruning (LR), Kaplan-Meier distance of survival curves (KM), martingale residuals (MR), Poisson regression for censored data (PR), within-node impurity (WI), and exponential log-likelihood loss (XL). With the exception of LR, initial trees are pruned by using split-complexity, and final trees are selected by means of cross-validation. We employ a real dataset from a clinical study of patients with gallbladder stones. The predictive error is evaluated using the integrated Brier score for censored data. The relationship between split selection instability and predictive error is evaluated by means of box-percentile plots, covariate and cutpoint selection entropy, and cutpoint selection coefficients of variation, respectively, in the root node. We found a positive association between covariate selection instability and predictive error in the root node. LR yields the lowest predictive error, while KM and MR yield the highest predictive error. The predictive error of survival trees is related to split selection instability. Based on the low predictive error of LR, we recommend the use of this algorithm for the construction of survival trees. Unpruned survival trees with multivariate p-value adjustment can perform equally well compared to pruned trees. The analysis of split selection instability can be used to communicate the results of tree-based analyses to clinicians and to support the application of survival trees.

A simple X-ray source of two orthogonal beams for small samples imaging

NASA Astrophysics Data System (ADS)

Hrdý, J.

2018-04-01

A simple method for simultaneous imaging of small samples by two orthogonal beams is proposed. The method is based on one channel-cut crystal which is oriented such that the beam is diffracted on two crystallographic planes simultaneously. These planes are symmetrically inclined to the crystal surface. The beams are three times diffracted. After the first diffraction the beam is split. After the second diffraction the split beams become parallel. Finally, after the third diffraction the beams become convergent and may be used for imaging. The corresponding angular relations to obtain orthogonal beams are derived.

Modification of the random forest algorithm to avoid statistical dependence problems when classifying remote sensing imagery

NASA Astrophysics Data System (ADS)

Cánovas-García, Fulgencio; Alonso-Sarría, Francisco; Gomariz-Castillo, Francisco; Oñate-Valdivieso, Fernando

2017-06-01

Random forest is a classification technique widely used in remote sensing. One of its advantages is that it produces an estimation of classification accuracy based on the so called out-of-bag cross-validation method. It is usually assumed that such estimation is not biased and may be used instead of validation based on an external data-set or a cross-validation external to the algorithm. In this paper we show that this is not necessarily the case when classifying remote sensing imagery using training areas with several pixels or objects. According to our results, out-of-bag cross-validation clearly overestimates accuracy, both overall and per class. The reason is that, in a training patch, pixels or objects are not independent (from a statistical point of view) of each other; however, they are split by bootstrapping into in-bag and out-of-bag as if they were really independent. We believe that putting whole patch, rather than pixels/objects, in one or the other set would produce a less biased out-of-bag cross-validation. To deal with the problem, we propose a modification of the random forest algorithm to split training patches instead of the pixels (or objects) that compose them. This modified algorithm does not overestimate accuracy and has no lower predictive capability than the original. When its results are validated with an external data-set, the accuracy is not different from that obtained with the original algorithm. We analysed three remote sensing images with different classification approaches (pixel and object based); in the three cases reported, the modification we propose produces a less biased accuracy estimation.

Sampling design and procedures for fixed surface-water sites in the Georgia-Florida coastal plain study unit, 1993

USGS Publications Warehouse

Hatzell, H.H.; Oaksford, E.T.; Asbury, C.E.

1995-01-01

The implementation of design guidelines for the National Water-Quality Assessment (NAWQA) Program has resulted in the development of new sampling procedures and the modification of existing procedures commonly used in the Water Resources Division of the U.S. Geological Survey. The Georgia-Florida Coastal Plain (GAFL) study unit began the intensive data collection phase of the program in October 1992. This report documents the implementation of the NAWQA guidelines by describing the sampling design and procedures for collecting surface-water samples in the GAFL study unit in 1993. This documentation is provided for agencies that use water-quality data and for future study units that will be entering the intensive phase of data collection. The sampling design is intended to account for large- and small-scale spatial variations, and temporal variations in water quality for the study area. Nine fixed sites were selected in drainage basins of different sizes and different land-use characteristics located in different land-resource provinces. Each of the nine fixed sites was sampled regularly for a combination of six constituent groups composed of physical and chemical constituents: field measurements, major ions and metals, nutrients, organic carbon, pesticides, and suspended sediments. Some sites were also sampled during high-flow conditions and storm events. Discussion of the sampling procedure is divided into three phases: sample collection, sample splitting, and sample processing. A cone splitter was used to split water samples for the analysis of the sampling constituent groups except organic carbon from approximately nine liters of stream water collected at four fixed sites that were sampled intensively. An example of the sample splitting schemes designed to provide the sample volumes required for each sample constituent group is described in detail. Information about onsite sample processing has been organized into a flowchart that describes a pathway for each of the constituent groups.

Non-lethal sampling of walleye for stable isotope analysis: a comparison of three tissues

USGS Publications Warehouse

Chipps, Steven R.; VanDeHey, J.A.; Fincel, M.J.

2012-01-01

Stable isotope analysis of fishes is often performed using muscle or organ tissues that require sacrificing animals. Non-lethal sampling provides an alternative for evaluating isotopic composition for species of concern or individuals of exceptional value. Stable isotope values of white muscle (lethal) were compared with those from fins and scales (non-lethal) in walleye, Sander vitreus (Mitchill), from multiple systems, size classes and across a range of isotopic values. Isotopic variability was also compared among populations to determine the potential of non-lethal tissues for diet-variability analyses. Muscle-derived isotope values were enriched compared with fins and depleted relative to scales. A split-sample validation technique and linear regression found that isotopic composition of walleye fins and scales was significantly related to that in muscle tissue for both δ13C and δ15N (r2 = 0.79–0.93). However, isotopic variability was significantly different between tissue types in two of six populations for δ15N and three of six populations for δ13C. Although species and population specific, these findings indicate that isotopic measures obtained from non-lethal tissues are indicative of those obtained from muscle.

Investigation of electronic and magnetic properties of Ni0.5Cu0.5Fe2O4: theoretical and experimental

NASA Astrophysics Data System (ADS)

Sharma, Uma Shankar; Shah, Rashmi

2018-05-01

In present study, Ni0.5Cu0.5Fe2O4 been was synthesized with Co-precipitation method and prepared samples were annealed at 300°C and 500°C. The single phase formation of nickel ferrite was confirmed through powder X-ray diffraction (XRD). The presence of various functional groups was confirmed through FTIR analysis. The effects of the annealing temperature on the particle sizes and magnetic properties of the ferrite samples were investigated and interpret with valid reasons. The structural and magnetic properties of the ferrite samples were strongly affected by the annealing temperature. The annealing temperature increases coercivity and saturation magnetization values are continuously increased. Spin­ polarization calculations are performed on the Ni0.5Cu0.5Fe2O4, compounds within density functional theory (DFT) and find out equilibrium lattice constants 8.2 Å and DOS show there exists large spin splitting between the spin up and spin down channels near the Fermi level confirm p-d hybridization. The theoretical calculated magnetic are slightly higher than our experimental results. The other results have been discussed in detail.

Development of a New Multidimensional Individual and Interpersonal Resilience Measure for Older Adults

PubMed Central

Martin, A’verria Sirkin; Distelberg, Brian; Palmer, Barton W.; Jeste, Dilip V.

2015-01-01

Objectives Develop an empirically grounded measure that can be used to assess family and individual resilience in a population of older adults (aged 50-99). Methods Cross-sectional, self-report data from 1,006 older adults were analyzed in two steps. The total sample was split into two sub-samples and the first step identified the underlying latent structure through principal component Exploratory Factor Analysis (EFA). The second step utilized the second half of the sample to validate the derived latent structure through Confirmatory Factor Analysis (CFA). Results EFA produced an eight-factor structure that appeared clinically relevant for measuring the multidimensional nature of resilience. Factors included self-efficacy, access to social support network, optimism, perceived economic and social resources, spirituality and religiosity, relational accord, emotional expression and communication, and emotional regulation. CFA confirmed the eight-factor structure previously achieved with covariance between each of the factors. Based on these analyses we developed the Multidimensional Individual and Interpersonal Resilience Measure (MIIRM), a broad assessment of resilience for older adults. Conclusion This study highlights the multidimensional nature of resilience and introduces an individual and interpersonal resilience measure developed for older adults which is grounded in the individual and family resilience literature. PMID:24787701

Portfolio of automated trading systems: complexity and learning set size issues.

PubMed

Raudys, Sarunas

2013-03-01

In this paper, we consider using profit/loss histories of multiple automated trading systems (ATSs) as N input variables in portfolio management. By means of multivariate statistical analysis and simulation studies, we analyze the influences of sample size (L) and input dimensionality on the accuracy of determining the portfolio weights. We find that degradation in portfolio performance due to inexact estimation of N means and N(N - 1)/2 correlations is proportional to N/L; however, estimation of N variances does not worsen the result. To reduce unhelpful sample size/dimensionality effects, we perform a clustering of N time series and split them into a small number of blocks. Each block is composed of mutually correlated ATSs. It generates an expert trading agent based on a nontrainable 1/N portfolio rule. To increase the diversity of the expert agents, we use training sets of different lengths for clustering. In the output of the portfolio management system, the regularized mean-variance framework-based fusion agent is developed in each walk-forward step of an out-of-sample portfolio validation experiment. Experiments with the real financial data (2003-2012) confirm the effectiveness of the suggested approach.

Improving the accuracy of sediment-associated constituent concentrations in whole storm water samples by wet-sieving

USGS Publications Warehouse

Selbig, W.R.; Bannerman, R.; Bowman, G.

2007-01-01

Sand-sized particles (>63 ??m) in whole storm water samples collected from urban runoff have the potential to produce data with substantial bias and/or poor precision both during sample splitting and laboratory analysis. New techniques were evaluated in an effort to overcome some of the limitations associated with sample splitting and analyzing whole storm water samples containing sand-sized particles. Wet-sieving separates sand-sized particles from a whole storm water sample. Once separated, both the sieved solids and the remaining aqueous (water suspension of particles less than 63 ??m) samples were analyzed for total recoverable metals using a modification of USEPA Method 200.7. The modified version digests the entire sample, rather than an aliquot, of the sample. Using a total recoverable acid digestion on the entire contents of the sieved solid and aqueous samples improved the accuracy of the derived sediment-associated constituent concentrations. Concentration values of sieved solid and aqueous samples can later be summed to determine an event mean concentration. ?? ASA, CSSA, SSSA.

Validation and Psychometric Properties of Mobile Phone Problematic Use Scale (MPPUS) in University Students of Tehran

PubMed Central

Mohammadi Kalhori, Soroush; Mohammadi, Mohammad Reza; Jannatifard, Fereshteh; Sepahbodi, Ghazal; Baba Reisi, Mohammad; Sajedi, Sahar; Farshchi, Mojtaba; KhodaKarami, Rasul; Hatami Kasvaee, Vahid

2015-01-01

Objective: Despite the fact that the mobile phone has become a pervasive technology of our time, little research has been done on mobile dependency. Therefore, a valid and reliable instrument, conforming to Iranian culture seems essential. The aim of our study was to validate the Iranian version of MPPUS (Mobile Phone Problematic Use Scale). Methods: This was a cross-sectional research, in which data were collected from 600 students studying at Tehran universities. Stratified sampling method was used to collect data. All participants completed Demographic Questionnaire, Cellular Phone Dependency Questionnaire (CPDQ) anonymously. Finally, a clinical interview (based on DSM-IV-TR) was conducted with 100 participants. Data were analyzed using concurrent validity, factor analysis, internal consistency (Cronbach’s’α), split half, test-retest and ROC Curve by SPSS18 Software. Results: As a result of reliability analysis and factor analysis by principal component and Varimax rotation, we extracted three factors including preoccupation, withdrawal symptoms and overuse of mobile phones in both males and females. Internal consistency (Cronbach’s alpha) of the MPPUS was .91; Cronbach’s alpha of the factors was .87, .70, .82 respectively. The test-retest correlation of the MPPUS was .56. The best cut off point for this questionnaire (MPPUS) was 160. Conclusion: The MPPUS proved to be a reliable questionnaire with adequate factor models to assess the extent of problems caused by the “misuse” of mobile phones in the Iranian society; however, further studies are needed on this topic. PMID:26005477

Optimization of multilayer neural network parameters for speaker recognition

NASA Astrophysics Data System (ADS)

Tovarek, Jaromir; Partila, Pavol; Rozhon, Jan; Voznak, Miroslav; Skapa, Jan; Uhrin, Dominik; Chmelikova, Zdenka

2016-05-01

This article discusses the impact of multilayer neural network parameters for speaker identification. The main task of speaker identification is to find a specific person in the known set of speakers. It means that the voice of an unknown speaker (wanted person) belongs to a group of reference speakers from the voice database. One of the requests was to develop the text-independent system, which means to classify wanted person regardless of content and language. Multilayer neural network has been used for speaker identification in this research. Artificial neural network (ANN) needs to set parameters like activation function of neurons, steepness of activation functions, learning rate, the maximum number of iterations and a number of neurons in the hidden and output layers. ANN accuracy and validation time are directly influenced by the parameter settings. Different roles require different settings. Identification accuracy and ANN validation time were evaluated with the same input data but different parameter settings. The goal was to find parameters for the neural network with the highest precision and shortest validation time. Input data of neural networks are a Mel-frequency cepstral coefficients (MFCC). These parameters describe the properties of the vocal tract. Audio samples were recorded for all speakers in a laboratory environment. Training, testing and validation data set were split into 70, 15 and 15 %. The result of the research described in this article is different parameter setting for the multilayer neural network for four speakers.

Can Touch Screen Tablets be Used to Assess Cognitive and Motor Skills in Early Years Primary School Children? A Cross-Cultural Study.

PubMed

Pitchford, Nicola J; Outhwaite, Laura A

2016-01-01

Assessment of cognitive and motor functions is fundamental for developmental and neuropsychological profiling. Assessments are usually conducted on an individual basis, with a trained examiner, using standardized paper and pencil tests, and can take up to an hour or more to complete, depending on the nature of the test. This makes traditional standardized assessments of child development largely unsuitable for use in low-income countries. Touch screen tablets afford the opportunity to assess cognitive functions in groups of participants, with untrained administrators, with precision recording of responses, thus automating the assessment process. In turn, this enables cognitive profiling to be conducted in contexts where access to qualified examiners and standardized assessments are rarely available. As such, touch screen assessments could provide a means of assessing child development in both low- and high-income countries, which would afford cross-cultural comparisons to be made with the same assessment tool. However, before touch screen tablet assessments can be used for cognitive profiling in low-to-high-income countries they need to be shown to provide reliable and valid measures of performance. We report the development of a new touch screen tablet assessment of basic cognitive and motor functions for use with early years primary school children in low- and high-income countries. Measures of spatial intelligence, visual attention, short-term memory, working memory, manual processing speed, and manual coordination are included as well as mathematical knowledge. To investigate if this new touch screen assessment tool can be used for cross-cultural comparisons we administered it to a sample of children ( N = 283) spanning standards 1-3 in a low-income country, Malawi, and a smaller sample of children ( N = 70) from first year of formal schooling from a high-income country, the UK. Split-half reliability, test-retest reliability, face validity, convergent construct validity, predictive criterion validity, and concurrent criterion validity were investigated. Results demonstrate "proof of concept" that touch screen tablet technology can provide reliable and valid psychometric measures of performance in the early years, highlighting its potential to be used in cross-cultural comparisons and research.

The Validity and Reliability of the Persian Version Test of Mobile Phone Dependency (TMD).

PubMed

Mohammadi, Mohammadreza; Alavi, Seyyed Salman; Farokhzad, Pegah; Jannatifard, Fereshteh; Mohammadi Kalhori, Soroush; Sepahbodi, Ghazal; Baba Reisi, Mohammad; Sajedi, Sanaz; Farshchi, Mojtaba; Khoda Karami, Rasul; Hatami Kasvaee, Vahid; Sepasi, Neda; Alavi, Samaneh Sadat

2015-09-01

‎ ‏ ‏Despite the fact that ‎the mobile phone has become a ‎pervasive technology of our time, ‎little research has been done on ‎mobile dependency. A valid and ‎reliable assessment instrument ‎corresponding to the Persian ‎culture is essential. This study ‎aimed to describe the ‎construction and validation of the ‎Persian version of TMD (Test of ‎Mobile phone Dependency) to ‎assess the addictive use of ‎mobile phone.‎ This was a cross-‎sectional study, for which data ‎were collected from 350 students ‎who were studying at Tehran ‎universities. Sampling method ‎was quota sampling. The ‎participants anonymously ‎completed the demographic ‎questionnaire, and CPDQ as a ‎valid questionnaire and gold ‎standard. Finally, clinical ‎interview [based on DSM-IV-TR] ‎was performed. To analyze the ‎data, concurrent validity, factor ‎analysis, internal consistency ‎‎(Cronbachα), split half; test-retest ‎and ROC Curve by SPSS18 ‎Software were used.‎ As a result of the ‎reliability analysis and factor ‎analysis by principal component ‎and Varimax rotation, three ‎factors ("salient", "preoccupation" ‎and "Spend a lot of time and ‎money") for both male and ‎female participants were ‎extracted. Internal consistency ‎‎(Cronbach's alpha) of the TMD ‎was .92 (Cronbach alpha of the ‎factors is .88, .82, and .84, ‎respectively). The test-retest ‎correlation of the TMD was ‎‎.56.The best cut off point for this ‎questionnaire (TMD) is 38.‎ The TMD proved to ‎have an acceptable internal ‎consistency with adequate factor ‎models to assess the extent of ‎problems caused by the "misuse" ‎of the mobile phone in the ‎Iranian society. Therefore, it can ‎be concluded that the Persian ‎version of the test was reliable ‎and valid; however, further ‎analysis is needed.‎.

The Validity and Reliability of the Persian Version Test of Mobile Phone Dependency (TMD)

PubMed Central

Mohammadi, Mohammadreza; Alavi, Seyyed Salman; Farokhzad, Pegah; Jannatifard, Fereshteh; Mohammadi Kalhori, Soroush; Sepahbodi, Ghazal; Baba Reisi, Mohammad; Sajedi, Sanaz; Farshchi, Mojtaba; Khoda Karami, Rasul; Hatami Kasvaee, Vahid; Sepasi, Neda; Alavi, Samaneh Sadat

2015-01-01

Objective: ‎‏ ‏Despite the fact that ‎the mobile phone has become a ‎pervasive technology of our time, ‎little research has been done on ‎mobile dependency. A valid and ‎reliable assessment instrument ‎corresponding to the Persian ‎culture is essential. This study ‎aimed to describe the ‎construction and validation of the ‎Persian version of TMD (Test of ‎Mobile phone Dependency) to ‎assess the addictive use of ‎mobile phone.‎ Methods: This was a cross-‎sectional study, for which data ‎were collected from 350 students ‎who were studying at Tehran ‎universities. Sampling method ‎was quota sampling. The ‎participants anonymously ‎completed the demographic ‎questionnaire, and CPDQ as a ‎valid questionnaire and gold ‎standard. Finally, clinical ‎interview [based on DSM-IV-TR] ‎was performed. To analyze the ‎data, concurrent validity, factor ‎analysis, internal consistency ‎‎(Cronbachα), split half; test-retest ‎and ROC Curve by SPSS18 ‎Software were used.‎ Results: As a result of the ‎reliability analysis and factor ‎analysis by principal component ‎and Varimax rotation, three ‎factors (“salient”, “preoccupation” ‎and “Spend a lot of time and ‎money”) for both male and ‎female participants were ‎extracted. Internal consistency ‎‎(Cronbach's alpha) of the TMD ‎was .92 (Cronbach alpha of the ‎factors is .88, .82, and .84, ‎respectively). The test-retest ‎correlation of the TMD was ‎‎.56.The best cut off point for this ‎questionnaire (TMD) is 38.‎ Conclusion: The TMD proved to ‎have an acceptable internal ‎consistency with adequate factor ‎models to assess the extent of ‎problems caused by the "misuse" ‎of the mobile phone in the ‎Iranian society. Therefore, it can ‎be concluded that the Persian ‎version of the test was reliable ‎and valid; however, further ‎analysis is needed.‎ PMID:27006671

Development of the SaFETy Score: A Clinical Screening Tool for Predicting Future Firearm Violence Risk

PubMed Central

Goldstick, Jason E.; Carter, Patrick M.; Walton, Maureen A.; Dahlberg, Linda L.; Sumner, Steven A.; Zimmerman, Marc A.; Cunningham, Rebecca M.

2017-01-01

Background Interpersonal firearm violence among youth is a substantial public health problem, and emergency department (ED) physicians require a clinical screening tool to identify high-risk youth. Objective To derive a clinically feasible risk index for firearm violence. Design 24-month prospective cohort study. Setting Urban, level 1 ED. Participants Substance-using youths, aged 14 to 24 years, seeking ED care for an assault-related injury and a proportionately sampled group of non–assault-injured youth enrolled from September 2009 through December 2011. Measurements Firearm violence (victimization/perpetration) and validated questionnaire items. Results A total of 599 youths were enrolled, and presence/absence of future firearm violence during follow-up could be ascertained in 483 (52.2% were positive). The sample was randomly split into training (75%) and post–score-construction validation (25%) sets. Using elastic-net penalized logistic regression, 118 baseline predictors were jointly analyzed; the most predictive variables fell predominantly into 4 domains: violence victimization, community exposure, peer influences, and fighting. By selection of 1 item from each domain, the 10-point SaFETy (Serious fighting, Friend weapon carrying, community Environment, and firearm Threats) score was derived. SaFETy was associated with firearm violence in the validation set (odds ratio [OR], 1.47 [95% CI, 1.23 to 1.79]); this association remained (OR, 1.44 [CI, 1.20 to 1.76]) after adjustment for reason for ED visit. In 5 risk strata observed in the training data, firearm violence rates in the validation set were 18.2% (2 of 11), 40.0% (18 of 45), 55.8% (24 of 43), 81.3% (13 of 16), and 100.0% (6 of 6), respectively. Limitations The study was conducted in a single ED and involved substance-using youths. SaFETy was not externally validated. Conclusion The SaFETy score is a 4-item score based on clinically feasible questionnaire items and is associated with firearm violence. Although broader validation is required, SaFETy shows potential to guide resource allocation for prevention of firearm violence. Primary Funding Source National Institute on Drug Abuse R01024646. PMID:28395357

Developing a Workflow Composite Score to Measure Clinical Information Logistics. A Top-down Approach.

PubMed

Liebe, J D; Hübner, U; Straede, M C; Thye, J

2015-01-01

Availability and usage of individual IT applications have been studied intensively in the past years. Recently, IT support of clinical processes is attaining increasing attention. The underlying construct that describes the IT support of clinical workflows is clinical information logistics. This construct needs to be better understood, operationalised and measured. It is therefore the aim of this study to propose and develop a workflow composite score (WCS) for measuring clinical information logistics and to examine its quality based on reliability and validity analyses. We largely followed the procedural model of MacKenzie and colleagues (2011) for defining and conceptualising the construct domain, for developing the measurement instrument, assessing the content validity, pretesting the instrument, specifying the model, capturing the data and computing the WCS and testing the reliability and validity. Clinical information logistics was decomposed into the descriptors data and information, function, integration and distribution, which embraced the framework validated by an analysis of the international literature. This framework was refined selecting representative clinical processes. We chose ward rounds, pre- and post-surgery processes and discharge as sample processes that served as concrete instances for the measurements. They are sufficiently complex, represent core clinical processes and involve different professions, departments and settings. The score was computed on the basis of data from 183 hospitals of different size, ownership, location and teaching status. Testing the reliability and validity yielded encouraging results: the reliability was high with r(split-half) = 0.89, the WCS discriminated between groups; the WCS correlated significantly and moderately with two EHR models and the WCS received good evaluation results by a sample of chief information officers (n = 67). These findings suggest the further utilisation of the WCS. As the WCS does not assume ideal workflows as a gold standard but measures IT support of clinical workflows according to validated descriptors a high portability of the WCS to other hospitals in other countries is very likely. The WCS will contribute to a better understanding of the construct clinical information logistics.

Delamination Fracture Related to Tempering in a High-Strength Low-Alloy Steel

NASA Astrophysics Data System (ADS)

Yan, Wei; Sha, Wei; Zhu, Lin; Wang, Wei; Shan, Yi-Yin; Yang, Ke

2010-01-01

The delamination or splitting of mechanical test specimens of rolled steel plate is a phenomenon that has been studied for many years. In the present study, splitting during fracture of tensile and Charpy V-notch (CVN) test specimens is examined in a high-strength low-alloy plate steel. It is shown that delamination did not occur in test specimens from plate in the as-rolled condition, but was severe in material tempered in the temperature range 500 °C to 650 °C. Minor splitting was seen after heating to 200 °C, 400 °C, and 700 °C. Samples that had been triple quenched and tempered to produce a fine equiaxed grain size also did not exhibit splitting. Microstructural and preferred orientation studies are presented and are discussed as they relate to the splitting phenomenon. It is concluded that the elongated as-rolled grains and grain boundary embrittlement resulting from precipitates (carbides and nitrides) formed during reheating were responsible for the delamination.

Precision ESR Measurements of Transverse Anisotropy in the Single-molecule Magnet Ni4

NASA Astrophysics Data System (ADS)

Friedman, Jonathan; Collett, Charles; Allao Cassaro, Rafael

We present a method to precisely determine the transverse anisotropy in a single-molecule magnet (SMM) through electron-spin resonance measurements of a tunnel splitting that arises from the anisotropy via first-order perturbation theory. We demonstrate the technique using the SMM Ni4 diluted via co-crystallization in a diamagnetic isostructural analogue. At 5% dilution, we find markedly narrower resonance peaks than are observed in undiluted samples. Ni4 has a zero-field tunnel splitting of 4 GHz, and we measure that transition at several nearby frequencies using custom loop-gap resonators, allowing a precise determination of the tunnel splitting. Because the transition under investigation arises due to a first-order perturbation from the transverse anisotropy, and lies at zero field, we can relate the splitting to the transverse anisotropy independent of any other Hamiltonian parameters. This method can be applied to other SMMs with zero-field tunnel splittings arising from first-order transverse anisotropy perturbations. NSF Grant No. DMR-1310135.

Capillary electrophoresis tandem mass spectrometry determination of glutamic acid and homocysteine's metabolites: Potential biomarkers of amyotrophic lateral sclerosis.

PubMed

Cieslarova, Zuzana; Lopes, Fernando Silva; do Lago, Claudimir Lucio; França, Marcondes Cavalcante; Colnaghi Simionato, Ana Valéria

2017-08-01

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease that affects both lower and upper motor neurons, leading to muscle atrophy, paralysis, and death caused by respiratory failure or infectious complications. Altered levels of homocysteine, cysteine, methionine, and glutamic acid have been observed in plasma of ALS patients. In this context, a method for determination of these potential biomarkers in plasma by capillary electrophoresis tandem mass spectrometry (CE-MS/MS) is proposed herein. Sample preparation was carefully investigated, since sulfur-containing amino acids may interact with plasma proteins. Owing to the non-thiol sulfur atom in methionine, it was necessary to split sample preparation into two methods: i) determination of homocysteine and cysteine as S-acetyl amino acids; ii) determination of glutamic acid and methionine. All amino acids were separated within 25min by CE-MS/MS using 5molL -1 acetic acid as background electrolyte and 5mmolL -1 acetic acid in 50% methanol/H 2 O (v/v) as sheath liquid. The proposed CE-MS/MS method was validated, presenting RSD values below 6% and 11% for intra- and inter-day precision, respectively, for the middle concentration level within the linear range. The limits of detection ranged from 35 (homocysteine) to 268nmolL -1 (glutamic acid). The validated method was applied to the analysis of plasma samples from a group of healthy individuals and patients with ALS, showing the potential of glutamic acid and homocysteine metabolites as biomarkers of ALS. Copyright © 2017 Elsevier B.V. All rights reserved.

Estimation of whole body fat from appendicular soft tissue from peripheral quantitative computed tomography in adolescent girls

PubMed Central

Lee, Vinson R.; Blew, Rob M.; Farr, Josh N.; Tomas, Rita; Lohman, Timothy G.; Going, Scott B.

2013-01-01

Objective Assess the utility of peripheral quantitative computed tomography (pQCT) for estimating whole body fat in adolescent girls. Research Methods and Procedures Our sample included 458 girls (aged 10.7 ± 1.1y, mean BMI = 18.5 ± 3.3 kg/m2) who had DXA scans for whole body percent fat (DXA %Fat). Soft tissue analysis of pQCT scans provided thigh and calf subcutaneous percent fat and thigh and calf muscle density (muscle fat content surrogates). Anthropometric variables included weight, height and BMI. Indices of maturity included age and maturity offset. The total sample was split into validation (VS; n = 304) and cross-validation (CS; n = 154) samples. Linear regression was used to develop prediction equations for estimating DXA %Fat from anthropometric variables and pQCT-derived soft tissue components in VS and the best prediction equation was applied to CS. Results Thigh and calf SFA %Fat were positively correlated with DXA %Fat (r = 0.84 to 0.85; p <0.001) and thigh and calf muscle densities were inversely related to DXA %Fat (r = −0.30 to −0.44; p < 0.001). The best equation for estimating %Fat included thigh and calf SFA %Fat and thigh and calf muscle density (adj. R2 = 0.90; SEE = 2.7%). Bland-Altman analysis in CS showed accurate estimates of percent fat (adj. R2 = 0.89; SEE = 2.7%) with no bias. Discussion Peripheral QCT derived indices of adiposity can be used to accurately estimate whole body percent fat in adolescent girls. PMID:25147482

Linguistic Validation and Cultural Adaptation of Bulgarian Version of Hospital Survey on Patient Safety Culture (HSOPSC).

PubMed

Stoyanova, Rumyana; Dimova, Rositsa; Tarnovska, Miglena; Boeva, Tatyana

2018-05-20

Patient safety (PS) is one of the essential elements of health care quality and a priority of healthcare systems in most countries. Thus the creation of validated instruments and the implementation of systems that measure patient safety are considered to be of great importance worldwide. The present paper aims to illustrate the process of linguistic validation, cross-cultural verification and adaptation of the Bulgarian version of the Hospital Survey on Patient Safety Culture (B-HSOPSC) and its test-retest reliability. The study design is cross-sectional. The HSOPSC questionnaire consists of 42 questions, grouped in 12 different subscales that measure patient safety culture. Internal con-sistency was assessed using Cronbach's alpha. The Wilcoxon signed-rank test and the split-half method were used; the Spear-man-Brown coefficient was calculated. The overall Cronbach's alpha for B-HSOPSC is 0.918. Subscales 7 Staffing and 12 Overall perceptions of safety had the lowest coefficients. The high reliability of the instrument was confirmed by the Split-half method (0.97) and ICC-coefficient (0.95). The lowest values of Spearmen-Broun coefficients were found in items A13 and A14. The study offers an analysis of the results of the linguistic validation of the B-HSOPSC and its test-retest reliability. The psychometric characteristics of the questions revealed good validity and reliability, except two questions. In the future, the instrument will be administered to the target population in the main study so that the psychometric properties of the instrument can be verified.

Reliability and validity of 12-item Short-Form health survey (SF-12) for the health status of Chinese community elderly population in Xujiahui district of Shanghai.

PubMed

Shou, Juan; Ren, Limin; Wang, Haitang; Yan, Fei; Cao, Xiaoyun; Wang, Hui; Wang, Zhiliang; Zhu, Shanzhu; Liu, Yao

2016-04-01

The 12-item Short-Form Health Survey (SF-12) is the abridged practical version of SF-36. This cross-sectional study was aimed to assess the reliability and validity of SF-12 for the health status of Chinese community elderly population. The Chinese community elderly people in Xujiahui district of Shanghai were investigated. The internal consistency reliability was assessed using Cronbach's alpha and split-half reliability coefficients. Construct validity was analyzed using exploratory factor analysis (EFA) and confirmatory factor analysis (CFA). Spearman's correlation coefficient (ρ) was used for the evaluation of criterion, convergent, and discriminant validity with Spearman's ρ ≥ 0.4 as satisfactory. Comparisons of the SF-12 summary scores among populations that differed in demographics were performed for discriminant validity. Total 1343 individuals aged ≥60 and <85 years old (response rate: 91.3 %) were analyzed. The Cronbach's α value (0.910) and the split-half reliability coefficient (0.812) reflected satisfactory internal consistency reliability of SF-12. EFA extracted a two-factor model (physical and mental health). About 60.7 % of the total variance was explained by the two factors. CFA showed that the two-factor solution provided a good fit to the data. Good convergent validity and discriminant validity of SF-12 were proved by the correction analyses (Spearman's ρ > 0.4) and the comparisons of the SF-12 summary scores among populations (P < 0.05). SF-12 summary scores were significantly correlated with the SF-36 summary scores (Spearman's ρ > 0.4, P < 0.05). In conclusion, SF-12 had satisfactory reliability and validity in measuring health status of Chinese community elderly population in Xujiahui district of Shanghai.

Automated, high-throughput platform for protein solubility screening using a split-GFP system

PubMed Central

Listwan, Pawel; Terwilliger, Thomas C.

2010-01-01

Overproduction of soluble and stable proteins for functional and structural studies is a major bottleneck for structural genomics programs and traditional biochemistry laboratories. Many high-payoff proteins that are important in various biological processes are “difficult to handle” as protein reagents in their native form. We have recently made several advances in enabling biochemical technologies for improving protein stability (http://www.lanl.gov/projects/gfp/), allowing stratagems for efficient protein domain trapping, solubility-improving mutations, and finding protein folding partners. In particular split-GFP protein tags are a very powerful tool for detection of stable protein domains. Soluble, stable proteins tagged with the 15 amino acid GFP fragment (amino acids 216–228) can be detected in vivo and in vitro using the engineered GFP 1–10 “detector” fragment (amino acids 1–215). If the small tag is accessible, the detector fragment spontaneously binds resulting in fluorescence. Here, we describe our current and on-going efforts to move this process from the bench (manual sample manipulation) to an automated, high-throughput, liquid-handling platform. We discuss optimization and validation of bacterial culture growth, lysis protocols, protein extraction, and assays of soluble and insoluble protein in multiple 96 well plate format. The optimized liquid-handling protocol can be used for rapid determination of the optimal, compact domains from single ORFS, collections of ORFS, or cDNA libraries. PMID:19039681

Chemical (knight) shift distortions of quadrupole-split deuteron powder spectra in solids

NASA Astrophysics Data System (ADS)

Torgeson, D. R.; Schoenberger, R. J.; Barnes, R. G.

In strong magnetic fields (e.g., 8 Tesla) anisotropy of the shift tensor (chemical or Knight shift) can alter the spacings of the features of quadrupole-split deuteron spectra of polycrystalline samples. Analysis of powder spectra yields both correct quadrupole coupling and symmetry parameters and all the components of the shift tensor. Synthetic and experimental examples are given to illustrate such behavior.

Development of splitting convergent beam electron diffraction (SCBED).

PubMed

Houdellier, Florent; Röder, Falk; Snoeck, Etienne

2015-12-01

Using a combination of condenser electrostatic biprism with dedicated electron optic conditions for sample illumination, we were able to split a convergent beam electron probe focused on the sample in two half focused probes without introducing any tilt between them. As a consequence, a combined convergent beam electron diffraction pattern is obtained in the back focal plane of the objective lens arising from two different sample areas, which could be analyzed in a single pattern. This splitting convergent beam electron diffraction (SCBED) pattern has been tested first on a well-characterized test sample of Si/SiGe multilayers epitaxially grown on a Si substrate. The SCBED pattern contains information from the strained area, which exhibits HOLZ lines broadening induced by surface relaxation, with fine HOLZ lines observed in the unstrained reference part of the sample. These patterns have been analyzed quantitatively using both parts of the SCBED transmitted disk. The fine HOLZ line positions are used to determine the precise acceleration voltage of the microscope while the perturbed HOLZ rocking curves in the stained area are compared to dynamical simulated ones. The combination of these two information leads to a precise evaluation of the sample strain state. Finally, several SCBED setups are proposed to tackle fundamental physics questions as well as applied materials science ones and demonstrate how SCBED has the potential to greatly expand the range of applications of electron diffraction and electron holography. Copyright © 2015 Elsevier B.V. All rights reserved.

Measurement of k T splitting scales in W→ℓν events at $$\\sqrt{s} = 7\\ \\mathrm{TeV}$$ with the ATLAS detector

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

Aad, G.; Abajyan, T.; Abbott, B.

2013-05-15

A measurement of splitting scales, as defined by the k T clustering algorithm, is presented for final states containing a W boson produced in proton–proton collisions at a centre-of-mass energy of 7 TeV. The measurement is based on the full 2010 data sample corresponding to an integrated luminosity of 36 pb -1 which was collected using the ATLAS detector at the CERN Large Hadron Collider. Cluster splitting scales are measured in events containing W bosons decaying to electrons or muons. The measurement comprises the four hardest splitting scales in a k T cluster sequence of the hadronic activity accompanying themore » W boson, and ratios of these splitting scales. Backgrounds such as multi-jet and top-quark-pair production are subtracted and the results are corrected for detector effects. Predictions from various Monte Carlo event generators at particle level are compared to the data. Overall, reasonable agreement is found with all generators, but larger deviations between the predictions and the data are evident in the soft regions of the splitting scales.« less

Split Hopkinson resonant bar test for sonic-frequency acoustic velocity and attenuation measurements of small, isotropic geological samples.

PubMed

Nakagawa, Seiji

2011-04-01

Mechanical properties (seismic velocities and attenuation) of geological materials are often frequency dependent, which necessitates measurements of the properties at frequencies relevant to a problem at hand. Conventional acoustic resonant bar tests allow measuring seismic properties of rocks and sediments at sonic frequencies (several kilohertz) that are close to the frequencies employed for geophysical exploration of oil and gas resources. However, the tests require a long, slender sample, which is often difficult to obtain from the deep subsurface or from weak and fractured geological formations. In this paper, an alternative measurement technique to conventional resonant bar tests is presented. This technique uses only a small, jacketed rock or sediment core sample mediating a pair of long, metal extension bars with attached seismic source and receiver-the same geometry as the split Hopkinson pressure bar test for large-strain, dynamic impact experiments. Because of the length and mass added to the sample, the resonance frequency of the entire system can be lowered significantly, compared to the sample alone. The experiment can be conducted under elevated confining pressures up to tens of MPa and temperatures above 100 [ordinal indicator, masculine]C, and concurrently with x-ray CT imaging. The described split Hopkinson resonant bar test is applied in two steps. First, extension and torsion-mode resonance frequencies and attenuation of the entire system are measured. Next, numerical inversions for the complex Young's and shear moduli of the sample are performed. One particularly important step is the correction of the inverted Young's moduli for the effect of sample-rod interfaces. Examples of the application are given for homogeneous, isotropic polymer samples, and a natural rock sample. © 2011 American Institute of Physics

Formation mechanism of TiO2 nanotubes and their applications in photoelectrochemical water splitting and supercapacitors.

PubMed

Chen, Bo; Hou, Junbo; Lu, Kathy

2013-05-14

Structural observations of the transition of TiO2 nanopores into nanotubes by increasing the OH(-) concentration in the electrolyte challenge the validity of existing formation mechanisms of anodic TiO2 nanotubes. In this study, dehydration of titanium hydroxide in the cell wall is proposed as the mechanism that leads to the separation of neighboring nanotubes. Based on this understanding, bamboo-type TiO2 nanotubes with large surface area and excellent interconnectivity are achieved by cycling high and low applied potentials. After thermal treatment in a H2 atmosphere, the bamboo-type TiO2 nanotubes show large photoelectrochemical water splitting efficiency and supercapacitors performace.

A split-crank bicycle ergometer uses servomotors to provide programmable pedal forces for studies in human biomechanics.

PubMed

Van der Loos, H F Machiel; Worthen-Chaudhari, Lise; Schwandt, Douglas; Bevly, David M; Kautz, Steven A

2010-08-01

This paper presents a novel computer-controlled bicycle ergometer, the TiltCycle, for use in human biomechanics studies of locomotion. The TiltCycle has a tilting (reclining) seat and backboard, a split pedal crankshaft to isolate the left and right loads to the feet of the pedaler, and two belt-driven, computer-controlled motors to provide assistance or resistance loads independently to each crank. Sensors measure the kinematics and force production of the legs to calculate work performed, and the system allows for goniometric and electromyography signals to be recorded. The technical description presented includes the mechanical design, low-level software and control algorithms, system identification and validation test results.

Empirical Monod-Beuneu relation of spin relaxation revisited for elemental metals

NASA Astrophysics Data System (ADS)

Szolnoki, L.; Kiss, A.; Forró, L.; Simon, F.

2014-03-01

Monod and Beuneu [P. Monod and F. Beuneu, Phys. Rev. B 19, 911 (1979), 10.1103/PhysRevB.19.911] established the validity of the Elliott-Yafet theory for elemental metals through correlating the experimental electron spin resonance linewidth with the so-called spin-orbit admixture coefficients and the momentum-relaxation theory. The spin-orbit admixture coefficients data were based on atomic spin-orbit splitting. We highlight two shortcomings of the previous description: (i) the momentum-relaxation involves the Debye temperature and the electron-phonon coupling whose variation among the elemental metals was neglected, (ii) the Elliott-Yafet theory involves matrix elements of the spin-orbit coupling (SOC), which are however not identical to the SOC induced energy splitting of the atomic levels, even though the two have similar magnitudes. We obtain the empirical spin-orbit admixture parameters for the alkali metals by considering the proper description of the momentum relaxation theory. In addition we present a model calculation, which highlights the difference between the SOC matrix element and energy splitting.

Direct solar-to-hydrogen conversion via inverted metamorphic multi-junction semiconductor architectures

DOE PAGES

Young, James L.; Steiner, Myles A.; Döscher, Henning; ...

2017-03-13

Solar water splitting via multi-junction semiconductor photoelectrochemical cells provides direct conversion of solar energy to stored chemical energy as hydrogen bonds. Economical hydrogen production demands high conversion efficiency to reduce balance-of-systems costs. For sufficient photovoltage, water-splitting efficiency is proportional to the device photocurrent, which can be tuned by judicious selection and integration of optimal semiconductor bandgaps. Here, we demonstrate highly efficient, immersed water-splitting electrodes enabled by inverted metamorphic epitaxy and a transparent graded buffer that allows the bandgap of each junction to be independently varied. Voltage losses at the electrolyte interface are reduced by 0.55 V over traditional, uniformly p-dopedmore » photocathodes by using a buried p-n junction. Lastly, advanced on-sun benchmarking, spectrally corrected and validated with incident photon-to-current efficiency, yields over 16% solar-to-hydrogen efficiency with GaInP/GaInAs tandem absorbers, representing a 60% improvement over the classical, high-efficiency tandem III-V device.« less

Direct solar-to-hydrogen conversion via inverted metamorphic multi-junction semiconductor architectures

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

Young, James L.; Steiner, Myles A.; Döscher, Henning

Solar water splitting via multi-junction semiconductor photoelectrochemical cells provides direct conversion of solar energy to stored chemical energy as hydrogen bonds. Economical hydrogen production demands high conversion efficiency to reduce balance-of-systems costs. For sufficient photovoltage, water-splitting efficiency is proportional to the device photocurrent, which can be tuned by judicious selection and integration of optimal semiconductor bandgaps. Here, we demonstrate highly efficient, immersed water-splitting electrodes enabled by inverted metamorphic epitaxy and a transparent graded buffer that allows the bandgap of each junction to be independently varied. Voltage losses at the electrolyte interface are reduced by 0.55 V over traditional, uniformly p-dopedmore » photocathodes by using a buried p-n junction. Lastly, advanced on-sun benchmarking, spectrally corrected and validated with incident photon-to-current efficiency, yields over 16% solar-to-hydrogen efficiency with GaInP/GaInAs tandem absorbers, representing a 60% improvement over the classical, high-efficiency tandem III-V device.« less

Development and validation of a questionnaire to assess carbohydrate and insulin-dosing knowledge in youth with type 1 diabetes.

PubMed

Koontz, Michaela B; Cuttler, Leona; Palmert, Mark R; O'Riordan, Maryann; Borawski, Elaine A; McConnell, Judy; Kern, Elizabeth O

2010-03-01

OBJECTIVE The American Diabetes Association advocates insulin regimens for youth with type 1 diabetes that involve adjusting insulin dose based on carbohydrate intake and blood glucose level. Implementing these regimens requires knowledge about carbohydrate content of foods and subsequent calculations of insulin dose, skills that may be difficult to gauge in practice. Therefore, we sought to develop and validate a questionnaire, the PedCarbQuiz (PCQ), to assess carbohydrate and insulin-dosing knowledge in youth with type 1 diabetes. RESEARCH DESIGN AND METHODS After development by an expert panel, the PCQ was administered to 75 youth with type 1 diabetes or their parents. Reliability was assessed by Cronbach alpha and split-half testing. To assess validity, scores were correlated with A1C, expert assessments, parent educational level, and complexity of insulin regimen. RESULTS PCQ mean score was 87 +/- 9.7% (range 42-98%). Cronbach alpha was 0.88, and correlation of split halves was 0.59 (P < 0.0001). Higher PCQ scores correlated significantly with lower A1C (r = -0.29, P = 0.01) and expert assessments (r = 0.56, P < 0.001). Scores were significantly higher in parents with college degrees than in those without (P = 0.01) and in participants with more complex insulin regimens (P = 0.003). CONCLUSIONS The PCQ is a novel, easily administered instrument to assess knowledge about carbohydrates and insulin dosing calculations. Initial analyses support the reliability and validity of the PCQ.

X-ray luminescence computed tomography imaging based on X-ray distribution model and adaptively split Bregman method

PubMed Central

Chen, Dongmei; Zhu, Shouping; Cao, Xu; Zhao, Fengjun; Liang, Jimin

2015-01-01

X-ray luminescence computed tomography (XLCT) has become a promising imaging technology for biological application based on phosphor nanoparticles. There are mainly three kinds of XLCT imaging systems: pencil beam XLCT, narrow beam XLCT and cone beam XLCT. Narrow beam XLCT can be regarded as a balance between the pencil beam mode and the cone-beam mode in terms of imaging efficiency and image quality. The collimated X-ray beams are assumed to be parallel ones in the traditional narrow beam XLCT. However, we observe that the cone beam X-rays are collimated into X-ray beams with fan-shaped broadening instead of parallel ones in our prototype narrow beam XLCT. Hence we incorporate the distribution of the X-ray beams in the physical model and collected the optical data from only two perpendicular directions to further speed up the scanning time. Meanwhile we propose a depth related adaptive regularized split Bregman (DARSB) method in reconstruction. The simulation experiments show that the proposed physical model and method can achieve better results in the location error, dice coefficient, mean square error and the intensity error than the traditional split Bregman method and validate the feasibility of method. The phantom experiment can obtain the location error less than 1.1 mm and validate that the incorporation of fan-shaped X-ray beams in our model can achieve better results than the parallel X-rays. PMID:26203388

Use of an ultra-clean sampling technique with inductively coupled plasma-mass spectrometry to determine trace-element concentrations in water from the Kirkwood-Cohansey Aquifer system, coastal plain, New Jersey

USGS Publications Warehouse

Ivahnenko, Tamara; Szabo, Zoltan; Hall, G.S.

1996-01-01

Water samples were collected during 1993 from 22 public supply wells screened in the Kirkwood-Cohansey aquifer system; concentrations of 18 trace elements were determined primarily by using inductively coupled plasma-mass spectrometry (ICP-MS) techniques, though graphite furnace atomic adsorption, hydride generation, and cold- vapor flameless atomic adsorption techniques were used for thallium, arsenic, and mercury, respectively, at the U.S. Geological Survey (USGS) National Water Quality Laboratory (NWQL). In addition, laboratory measurements of alkalinity and turbidity were made. The ground-water samples were collected by using ultra-clean sampling protocols developed by the USGS for collecting ground-water samples in areas with water containing low concentrations of trace elements. This technique is based on recently gained experience in sampling surface water for these elements. Field parameters (water temperature, specific conductance, pH, and dissolved-oxygen concentration) were monitored prior to sample collection. Three equipment blanks were collected to ensure that low-level trace-element contamination did not occur during sample collection. One split sample and a commercially- prepared reference standard were submitted to the NWQL o evaluate laboratory precision and accuracy, respectively. Trace-element concentrations in 10 sample splits and one equipment blank were also determined at the Rutgers University Chemistry Department laboratory. Results of the ICP-MS analyses and cold vapor flameless atomic absorption indicated that five trace elements-- cobalt, copper, lead, mercury, and nickel--were detectable in low concentrations (<0.1-29 mg/L) in most of the samples from the 22 wells, and four elements--aluminum, barium, manganese and zinc--were detected in higher concentrations than the other elements (30-710 mg/L for aluminum; 4-180 mg/L for barium, manganese, and zinc). The remaining nine trace elements were present in concentrations consistently lower than the minimum reporting limit. Turbidity was low (less than 1 nephelometric turbidity unit (NTU)), indicating that the trace-element concentrations were present in the dissolved phase and ideally would be reproducible in the absence of highly variable concentrations of particulates. The concentration of lead in one sample exceeded the U.S. Environmental Protection Agency (USEPA) action level of 15 mg/L; concentrations ranged from <1 to 16 mg/L. Mercury was frequently detected; concentrations ranged from <0.1 to 1.1 mg/L but did not exceed the USEPA maximum contaminant level. Results of analyses of the equipment blanks indicated that samples collected by using the new ultra-clean sampling protocols were free of low-level (< 1mg/L) trace-element contamination. The analysis of the split sample sent to the NWQL had a difference of 5 percent or less for all constituents except aluminum, for which the analysis had a difference of 10 percent. Results of ICP-MS analyses of split water samples sent to the Rutgers University Chemistry Department laboratory were, in general, in good agreement (within 10 percent) with those of the NWQL. Results of the analysis of the commercial standard agreed (within 5 percent) with the known concentrations of the trace elements. The quality-assurance data (three blanks, one split sample, and one standard), although not statistically evaluated because of the small data set, indicate that the measured trace-element concentrations are precise and accurate and that the samples were free of contamination at the microgram-per-liter level of contamination.

A Paradigm to Assess Implicit Attitudes towards God: The Positive/Negative God Associations Task.

PubMed

Pirutinsky, Steven; Carp, Sean; Rosmarin, David H

2017-02-01

Psychological research on the relationship between spirituality/religion and mental health has grown considerably over the past several decades and now constitutes a sizable body of scholarship. Among dimensions of S/R, positive beliefs about God have been significantly related to better mental health outcomes, and conversely negative beliefs about God are generally associated with more distress. However, prior research on this topic has relied heavily upon self-report Likert-type scales, which are vulnerable to self-report biases and measure only explicit cognitive processes. In this study, we developed and validated an implicit social cognition task, the Positive/Negative God Go/No-go Association Task (PNG-GNAT), for use in psychological research on spirituality and religion (S/R). Preliminary evidence in a large sample (N = 381) suggests that the PNG-GNAT demonstrates internal consistency, test-retest and split-half reliability, and concurrent evidence of validity. Further, our results suggest that PNG-GNAT scores represent different underlying dimensions of S/R than explicit self-report measures, and incrementally predict mental health above and beyond self-report assessment. The PNG-GNAT appears to be an effective tool for measuring implicit positive/negative beliefs about God.

Factor structure of the geriatric care environment scale.

PubMed

Kim, Hongsoo; Capezuti, Elizabeth; Boltz, Marie; Fairchild, Susan; Fulmer, Terry; Mezey, Mathy

2007-01-01

Older adults comprise approximately 60% of all adult, nonobstetric hospital admissions. Nurses Improving Care for Health System Elders (NICHE) is a national program aimed at system improvement to achieve patient-centered care for older adults. The NICHE hospitals use the Geriatric Institutional Assessment Profile (GIAP) to assess their institutional readiness to provide quality care to older adults and to document improvement in geriatric care delivery. To explore the factorial structure of the 28-item Geriatric Care Environment Scale (GCES) of the GIAP, test its validity with a sample of staff registered nurses (RNs), and evaluate its invariance across 4 groups of RNs who worked at 4 different types of hospitals. Staff RNs (N = 9,400) at 71 acute hospitals, who responded to the GIAP from 1999 to 2004, were split randomly into 2 groups for cross-validation. A 3-step data analysis was completed. The a priori factor structure was developed using exploratory factor analysis. The obtained factor model was validated, and its invariance by types of hospitals was examined by confirmatory factor analyses. The GCES is internally consistent (Cronbach's alpha = .93) and accounts for approximately 55% of the total variance. The 4 factors extracted from the exploratory factor analysis are Aging-Sensitive Care Delivery, Resource Availability, Institutional Values Regarding Older Adults and Staff, and Capacity for Collaboration. The 4-factor structured model is validated in a half-randomly selected sample (normed fit index [NFI] = .931, nonnormed fit index [NNFI] = .933, comparative fit index [CFI] = .939, root-mean-square error of approximation [RMSEA] = .058) and does not vary significantly across the 4 groups of RNs who worked at the 4 different types of hospitals (NFI = .969, NNFI = .975, CFI = .976, RMSEA = .027). The GCES is a reliable measure of RN perception of how care provided to older adults reflects age-sensitive principles and the organizational practice environment that supports or hinders care delivery.

A New Tool for Nutrition App Quality Evaluation (AQEL): Development, Validation, and Reliability Testing

PubMed Central

Huang, Wenhao; Chapman-Novakofski, Karen M

2017-01-01

Background The extensive availability and increasing use of mobile apps for nutrition-based health interventions makes evaluation of the quality of these apps crucial for integration of apps into nutritional counseling. Objective The goal of this research was the development, validation, and reliability testing of the app quality evaluation (AQEL) tool, an instrument for evaluating apps’ educational quality and technical functionality. Methods Items for evaluating app quality were adapted from website evaluations, with additional items added to evaluate the specific characteristics of apps, resulting in 79 initial items. Expert panels of nutrition and technology professionals and app users reviewed items for face and content validation. After recommended revisions, nutrition experts completed a second AQEL review to ensure clarity. On the basis of 150 sets of responses using the revised AQEL, principal component analysis was completed, reducing AQEL into 5 factors that underwent reliability testing, including internal consistency, split-half reliability, test-retest reliability, and interrater reliability (IRR). Two additional modifiable constructs for evaluating apps based on the age and needs of the target audience as selected by the evaluator were also tested for construct reliability. IRR testing using intraclass correlations (ICC) with all 7 constructs was conducted, with 15 dietitians evaluating one app. Results Development and validation resulted in the 51-item AQEL. These were reduced to 25 items in 5 factors after principal component analysis, plus 9 modifiable items in two constructs that were not included in principal component analysis. Internal consistency and split-half reliability of the following constructs derived from principal components analysis was good (Cronbach alpha >.80, Spearman-Brown coefficient >.80): behavior change potential, support of knowledge acquisition, app function, and skill development. App purpose split half-reliability was .65. Test-retest reliability showed no significant change over time (P>.05) for all but skill development (P=.001). Construct reliability was good for items assessing age appropriateness of apps for children, teens, and a general audience. In addition, construct reliability was acceptable for assessing app appropriateness for various target audiences (Cronbach alpha >.70). For the 5 main factors, ICC (1,k) was >.80, with a P value of <.05. When 15 nutrition professionals evaluated one app, ICC (2,15) was .98, with a P value of <.001 for all 7 constructs when the modifiable items were specified for adults seeking weight loss support. Conclusions Our preliminary effort shows that AQEL is a valid, reliable instrument for evaluating nutrition apps’ qualities for clinical interventions by nutrition clinicians, educators, and researchers. Further efforts in validating AQEL in various contexts are needed. PMID:29079554

Mixed-strain housing for female C57BL/6, DBA/2, and BALB/c mice: validating a split-plot design that promotes refinement and reduction.

PubMed

Walker, Michael; Fureix, Carole; Palme, Rupert; Newman, Jonathan A; Ahloy Dallaire, Jamie; Mason, Georgia

2016-01-27

Inefficient experimental designs are common in animal-based biomedical research, wasting resources and potentially leading to unreplicable results. Here we illustrate the intrinsic statistical power of split-plot designs, wherein three or more sub-units (e.g. individual subjects) differing in a variable of interest (e.g. genotype) share an experimental unit (e.g. a cage or litter) to which a treatment is applied (e.g. a drug, diet, or cage manipulation). We also empirically validate one example of such a design, mixing different mouse strains -- C57BL/6, DBA/2, and BALB/c -- within cages varying in degree of enrichment. As well as boosting statistical power, no other manipulations are needed for individual identification if co-housed strains are differentially pigmented, so also sparing mice from stressful marking procedures. The validation involved housing 240 females from weaning to 5 months of age in single- or mixed- strain trios, in cages allocated to enriched or standard treatments. Mice were screened for a range of 26 commonly-measured behavioural, physiological and haematological variables. Living in mixed-strain trios did not compromise mouse welfare (assessed via corticosterone metabolite output, stereotypic behaviour, signs of aggression, and other variables). It also did not alter the direction or magnitude of any strain- or enrichment-typical difference across the 26 measured variables, or increase variance in the data: indeed variance was significantly decreased by mixed- strain housing. Furthermore, using Monte Carlo simulations to quantify the statistical power benefits of this approach over a conventional design demonstrated that for our effect sizes, the split- plot design would require significantly fewer mice (under half in most cases) to achieve a power of 80%. Mixed-strain housing allows several strains to be tested at once, and potentially refines traditional marking practices for research mice. Furthermore, it dramatically illustrates the enhanced statistical power of split-plot designs, allowing many fewer animals to be used. More powerful designs can also increase the chances of replicable findings, and increase the ability of small-scale studies to yield significant results. Using mixed-strain housing for female C57BL/6, DBA/2 and BALB/c mice is therefore an effective, efficient way to promote both refinement and the reduction of animal-use in research.

Strain Rate Behavior of HTPB-Based Magnetorheological Materials

NASA Astrophysics Data System (ADS)

Stoltz, Chad; Seminuk, Kenneth; Joshi, Vasant

2013-06-01

It is of particular interest to determine whether the mechanical properties of binder systems can be manipulated by adding ferrous or Magnetostrictive particulates. Strain rate response of two HTPB/Fe (Hydroxyl-terminated Polybutadiene/Iron) compositions under electromagnetic fields has been investigated using a Split Hopkinson Pressure bar arrangement equipped with aluminum bars. Two HTPB/Fe compositions were developed, the first without plasticizer and the second containing plasticizer. Samples were tested with and without the application of a 0.01 Tesla magnetic field coil. Strain gauge data taken from the Split Hopkinson Pressure bar has been used to determine what mechanical properties were changed by inducing a mild electromagnetic field onto each sample. The data reduction method to obtain stress-strain plots included dispersion corrections for deciphering minute changes due to compositional alterations. Data collected from the Split Hopkinson Pressure bar indicate changes in the Mechanical Stress-Strain curves and suggest that the impedance of a binder system can be altered by means of a magnetic field. We acknowledge the Defense Threat Reduction Agency for funding.

A comparison of students' and jury panelists' decision-making in split recovery cases.

PubMed

Fox, Paul; Wingrove, Twila; Pfeifer, Courtney

2011-01-01

This study was designed to assess jury decision-making for 289 participants reading a medical malpractice vignette as a function of participant type (undergraduate students or jury panelists), punitive damage award apportionment (none, half, or all to the plaintiff), and compensation previously assigned to the plaintiff (low, medium, or high). We found several sample differences. Overall, jury panelists awarded more money for punitive damages. Jury panelists were also more affected by compensatory-relevant information when making punitive decisions, including assigning punitive damages and rating the fairness of the traditional apportionment scheme, where the plaintiff receives all of the money. Compared with students, more jury panelists were in favor of the plaintiff receiving the entire punitive award. Most students endorsed split recovery. The authors suggest that psycholegal research conducted solely with student samples, rather than community members, may misestimate the likely behavior of actual juries. The implications of the study for split recovery policy are also discussed. Copyright © 2011 John Wiley & Sons, Ltd.

Electric field metrology for SI traceability: Systematic measurement uncertainties in electromagnetically induced transparency in atomic vapor

NASA Astrophysics Data System (ADS)

Holloway, Christopher L.; Simons, Matt T.; Gordon, Joshua A.; Dienstfrey, Andrew; Anderson, David A.; Raithel, Georg

2017-06-01

We investigate the relationship between the Rabi frequency (ΩRF, related to the applied electric field) and Autler-Townes (AT) splitting, when performing atom-based radio-frequency (RF) electric (E) field strength measurements using Rydberg states and electromagnetically induced transparency (EIT) in an atomic vapor. The AT splitting satisfies, under certain conditions, a well-defined linear relationship with the applied RF field amplitude. The EIT/AT-based E-field measurement approach derived from these principles is currently being investigated by several groups around the world as a means to develop a new SI-traceable RF E-field measurement technique. We establish conditions under which the measured AT-splitting is an approximately linear function of the RF electric field. A quantitative description of systematic deviations from the linear relationship is key to exploiting EIT/AT-based atomic-vapor spectroscopy for SI-traceable field measurement. We show that the linear relationship is valid and can be used to determine the E-field strength, with minimal error, as long as the EIT linewidth is small compared to the AT-splitting. We also discuss interesting aspects of the thermal dependence (i.e., hot- versus cold-atom) of this EIT-AT technique. An analysis of the transition from cold- to hot-atom EIT in a Doppler-mismatched cascade system reveals a significant change of the dependence of the EIT linewidth on the optical Rabi frequencies and of the AT-splitting on ΩRF.

Accurate Identification of Fatty Liver Disease in Data Warehouse Utilizing Natural Language Processing.

PubMed

Redman, Joseph S; Natarajan, Yamini; Hou, Jason K; Wang, Jingqi; Hanif, Muzammil; Feng, Hua; Kramer, Jennifer R; Desiderio, Roxanne; Xu, Hua; El-Serag, Hashem B; Kanwal, Fasiha

2017-10-01

Natural language processing is a powerful technique of machine learning capable of maximizing data extraction from complex electronic medical records. We utilized this technique to develop algorithms capable of "reading" full-text radiology reports to accurately identify the presence of fatty liver disease. Abdominal ultrasound, computerized tomography, and magnetic resonance imaging reports were retrieved from the Veterans Affairs Corporate Data Warehouse from a random national sample of 652 patients. Radiographic fatty liver disease was determined by manual review by two physicians and verified with an expert radiologist. A split validation method was utilized for algorithm development. For all three imaging modalities, the algorithms could identify fatty liver disease with >90% recall and precision, with F-measures >90%. These algorithms could be used to rapidly screen patient records to establish a large cohort to facilitate epidemiological and clinical studies and examine the clinic course and outcomes of patients with radiographic hepatic steatosis.

Assessing the reading comprehension of adults with learning disabilities.

PubMed

Jones, F W; Long, K; Finlay, W M L

2006-06-01

This study's aim was to begin the process of measuring the reading comprehension of adults with mild and borderline learning disabilities, in order to generate information to help clinicians and other professionals to make written material for adults with learning disabilities more comprehensible. The Test for the Reception of Grammar (TROG), with items presented visually rather than orally, and the Reading Comprehension sub-test of the Wechsler Objective Reading Dimensions (WORD) battery were given to 24 service-users of a metropolitan community learning disability team who had an estimated IQ in the range 50-79. These tests were demonstrated to have satisfactory split-half reliability and convergent validity with this population, supporting both their use in this study and in clinical work. Data are presented concerning the distribution across the sample of reading-ages and the comprehension of written grammatical constructions. These data should be useful to those who are preparing written material for adults with learning disabilities.

The specific purpose Monte Carlo code McENL for simulating the response of epithermal neutron lifetime well logging tools

NASA Astrophysics Data System (ADS)

Prettyman, T. H.; Gardner, R. P.; Verghese, K.

1993-08-01

A new specific purpose Monte Carlo code called McENL for modeling the time response of epithermal neutron lifetime tools is described. The weight windows technique, employing splitting and Russian roulette, is used with an automated importance function based on the solution of an adjoint diffusion model to improve the code efficiency. Complete composition and density correlated sampling is also included in the code, and can be used to study the effect on tool response of small variations in the formation, borehole, or logging tool composition and density. An illustration of the latter application is given for the density of a thermal neutron filter. McENL was benchmarked against test-pit data for the Mobil pulsed neutron porosity tool and was found to be very accurate. Results of the experimental validation and details of code performance are presented.

A new titration system of a novel split-type superconducting magnet NMR spectrometer.

PubMed

Kitagawa, Isao; Tanaka, Hideki; Okada, Michiya; Kitaguchi, Hitoshi; Kohzuma, Takamitsu

2008-12-01

A new titration system for studying protein-ligand interactions has been developed. In this system, the sample solution is circulated in the route formed by an access path in a split superconducting magnet to maintain a constant protein concentration during the titration experiments. A concentration-control procedure for the ligand/protein ratio is devised, and the ligand/protein ratio is well controlled by this apparatus.

Stripline split-ring resonator with integrated optogalvanic sample cell

NASA Astrophysics Data System (ADS)

Persson, Anders; Berglund, Martin; Thornell, Greger; Possnert, Göran; Salehpour, Mehran

2014-04-01

Intracavity optogalvanic spectroscopy (ICOGS) has been proposed as a method for unambiguous detection of rare isotopes. Of particular interest is 14C, where detection of extremely low concentrations in the 1:1015 range (14C: 12C), is of interest in, e.g., radiocarbon dating and pharmaceutical sciences. However, recent reports show that ICOGS suffers from substantial problems with reproducibility. To qualify ICOGS as an analytical method, more stable and reliable plasma generation and signal detection are needed. In our proposed setup, critical parameters have been improved. We have utilized a stripline split-ring resonator microwave-induced microplasma source to excite and sustain the plasma. Such a microplasma source offers several advantages over conventional ICOGS plasma sources. For example, the stripline split-ring resonator concept employs separated plasma generation and signal detection, which enables sensitive detection at stable plasma conditions. The concept also permits in situ observation of the discharge conditions, which was found to improve reproducibility. Unique to the stripline split-ring resonator microplasma source in this study, is that the optogalvanic sample cell has been embedded in the device itself. This integration enables improved temperature control and more stable and accurate signal detection. Significant improvements are demonstrated, including reproducibility, signal-to-noise ratio, and precision.

[Reliability and validity analysis of simplified Chinese version of QOL questionnaire of olfactory disorders].

PubMed

Jin, X F; Wang, J; Li, Y J; Liu, J F; Ni, D F

2016-09-20

Objective: To cross-culturally translate the questionnaire of olfactory disorders(QOD)into a simplified Chinese version, and evaluate its reliability and validity in clinical. Method: A simplified Chinese version of the QOD was evaluated in test-retest reliability, split-half reliability and internal consistency.Then it was evaluated in validity test including content validity, criterion-related validity, responsibility. Criterion-related validity was using the medical outcome study's 36-item short rorm health survey(SF-36) and the World Health Organization quality of life-brief (WHOQOL-BREF) for comparison. Result: A total of 239 patients with olfactory dysfunction were enrolled and tested, in which 195 patients completed all three surveys(QOD, SF-36, WHOQOL-BREF). The test-retest reliabilities of the QOD-parosmia statements(QOD-P), QOD-quality of life(QOD-QoL), and the QOD-visual simulation(QOD-VAS)sections were 0.799( P <0.01),0.781( P <0.01),0.488( P <0.01), respectively, and the Cronbach' s α coefficients reliability were 0.477,0.812,0.889,respectively.The split-half reliability of QOD-QoL was 0.89. There was no correlation between the QOD-P section and the SF-36, but there were statistically significant correlations between the QOD-QoL and QOD-VAS sections with the SF-36. There was no correlation between the QOD-P section and the WHOQOL-BREF, but there were statistically significant correlations between the QOD-QoL and QOD-VAS sections with the SF-36 in most sections. Conclusion: The simplified Chinese version of the QOD was testified to be a reliable and valid questionnaire for evaluating patients with olfactory dysfunction living in mainland of China.The QOD-P section needs further modifications to properly adapt patients with Chinese cultural and knowledge background. Copyright© by the Editorial Department of Journal of Clinical Otorhinolaryngology Head and Neck Surgery.

A comparison of the conditional inference survival forest model to random survival forests based on a simulation study as well as on two applications with time-to-event data.

PubMed

Nasejje, Justine B; Mwambi, Henry; Dheda, Keertan; Lesosky, Maia

2017-07-28

Random survival forest (RSF) models have been identified as alternative methods to the Cox proportional hazards model in analysing time-to-event data. These methods, however, have been criticised for the bias that results from favouring covariates with many split-points and hence conditional inference forests for time-to-event data have been suggested. Conditional inference forests (CIF) are known to correct the bias in RSF models by separating the procedure for the best covariate to split on from that of the best split point search for the selected covariate. In this study, we compare the random survival forest model to the conditional inference model (CIF) using twenty-two simulated time-to-event datasets. We also analysed two real time-to-event datasets. The first dataset is based on the survival of children under-five years of age in Uganda and it consists of categorical covariates with most of them having more than two levels (many split-points). The second dataset is based on the survival of patients with extremely drug resistant tuberculosis (XDR TB) which consists of mainly categorical covariates with two levels (few split-points). The study findings indicate that the conditional inference forest model is superior to random survival forest models in analysing time-to-event data that consists of covariates with many split-points based on the values of the bootstrap cross-validated estimates for integrated Brier scores. However, conditional inference forests perform comparably similar to random survival forests models in analysing time-to-event data consisting of covariates with fewer split-points. Although survival forests are promising methods in analysing time-to-event data, it is important to identify the best forest model for analysis based on the nature of covariates of the dataset in question.

Modeling and Validation of Power-split and P2 Parallel Hybrid Electric Vehicles SAE 2013-01-1470)

EPA Science Inventory

The Advanced Light-Duty Powertrain and Hybrid Analysis tool was created by EPA to evaluate the Greenhouse Gas (GHG) emissions of Light-Duty (LD) vehicles. It is a physics-based, forward-looking, full vehicle computer simulator capable of analyzing various vehicle types combined ...

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

Simbeck, D.J.

Clinch River - Environmental Restoration Program (CR-ERP) personnel and Tennessee Valley Authority (TVA) personnel conducted a study during the week of October 21-28, 1993, as described in the Statement of Work (SOW) document. The organisms specified for testing were larval fathead minnows, Pimephales promelas, and the daphnid, Ceriodaphnia dubia. Due to serious reproduction/embryo abortion problems with the TVA daphnid cultures, TVA conducted tests during this study period using only fathead minnows. A split sample test using daphnids only will be scheduled during 1994 as a substitute for this study period. Surface water samples were collected by TVA Field Engineering personnelmore » from Poplar Creek Mile 2.9, Mile 4.3, and Mile 5.1 on October 20, 22, and 25. Samples were split and provided to the CR-ERP and TVA toxicology laboratories for testing. Exposure of test organisms to these samples resulted in no toxicity (survival or growth) in testing conducted by TVA.« less

US Geological Survey nutrient preservation experiment : experimental design, statistical analysis, and interpretation of analytical results

USGS Publications Warehouse

Patton, Charles J.; Gilroy, Edward J.

1999-01-01

Data on which this report is based, including nutrient concentrations in synthetic reference samples determined concurrently with those in real samples, are extensive (greater than 20,000 determinations) and have been published separately. In addition to confirming the well-documented instability of nitrite in acidified samples, this study also demonstrates that when biota are removed from samples at collection sites by 0.45-micrometer membrane filtration, subsequent preservation with sulfuric acid or mercury (II) provides no statistically significant improvement in nutrient concentration stability during storage at 4 degrees Celsius for 30 days. Biocide preservation had no statistically significant effect on the 30-day stability of phosphorus concentrations in whole-water splits from any of the 15 stations, but did stabilize Kjeldahl nitrogen concentrations in whole-water splits from three data-collection stations where ammonium accounted for at least half of the measured Kjeldahl nitrogen.

Assessing the organizational context for EBP implementation: the development and validity testing of the Implementation Climate Scale (ICS).

PubMed

Ehrhart, Mark G; Aarons, Gregory A; Farahnak, Lauren R

2014-10-23

Although the importance of the organizational environment for implementing evidence-based practices (EBP) has been widely recognized, there are limited options for measuring implementation climate in public sector health settings. The goal of this research was to develop and test a measure of EBP implementation climate that would both capture a broad range of issues important for effective EBP implementation and be of practical use to researchers and managers seeking to understand and improve the implementation of EBPs. Participants were 630 clinicians working in 128 work groups in 32 US-based mental health agencies. Items to measure climate for EBP implementation were developed based on past literature on implementation climate and other strategic climates and in consultation with experts on the implementation of EBPs in mental health settings. The sample was randomly split at the work group level of analysis; half of the sample was used for exploratory factor analysis (EFA), and the other half was used for confirmatory factor analysis (CFA). The entire sample was utilized for additional analyses assessing the reliability, support for level of aggregation, and construct-based evidence of validity. The EFA resulted in a final factor structure of six dimensions for the Implementation Climate Scale (ICS): 1) focus on EBP, 2) educational support for EBP, 3) recognition for EBP, 4) rewards for EBP, 5) selection for EBP, and 6) selection for openness. This structure was supported in the other half of the sample using CFA. Additional analyses supported the reliability and construct-based evidence of validity for the ICS, as well as the aggregation of the measure to the work group level. The ICS is a very brief (18 item) and pragmatic measure of a strategic climate for EBP implementation. It captures six dimensions of the organizational context that indicate to employees the extent to which their organization prioritizes and values the successful implementation of EBPs. The ICS can be used by researchers to better understand the role of the organizational context on implementation outcomes and by organizations to evaluate their current climate as they consider how to improve the likelihood of implementation success.

Model validations for low-global warming potential refrigerants in mini-split air-conditioning units

DOE PAGES

Shen, Bo; Shrestha, Som; Abdelaziz, Omar

2016-09-02

To identify low GWP (global warming potential) refrigerants to replace R-22 and R-410A, extensive experimental evaluations were conducted for multiple candidates of refrigerant at the standard test conditions and at high-ambient conditions with outdoor temperature varying from 27.8 C to 55.0 C.. In the study, R-22 was compared to propane (R-290), DR-3, ARM-20B, N-20B and R-444B in a mini-split air conditioning unit originally designed for R-22; R-410A was compared to R-32, DR-55, ARM-71A, L41-2 (R-447A) in a mini-split unit designed for R-410A. To reveal physics behind the measured performance results, thermodynamic properties of the alternative refrigerants were analysed. In addition,more » the experimental data was used to calibrate a physics-based equipment model, i.e. ORNL Heat Pump Design Model (HPDM). The calibrated model translated the experimental results to key calculated parameters, i.e. compressor efficiencies, refrigerant side two-phase heat transfer coefficients, corresponding to each refrigerant. As a result, these calculated values provide scientific insights on the performance of the alternative refrigerants and are useful for other applications beyond mini-split air conditioning units.« less

MIP Models and Hybrid Algorithms for Simultaneous Job Splitting and Scheduling on Unrelated Parallel Machines

PubMed Central

Ozmutlu, H. Cenk

2014-01-01

We developed mixed integer programming (MIP) models and hybrid genetic-local search algorithms for the scheduling problem of unrelated parallel machines with job sequence and machine-dependent setup times and with job splitting property. The first contribution of this paper is to introduce novel algorithms which make splitting and scheduling simultaneously with variable number of subjobs. We proposed simple chromosome structure which is constituted by random key numbers in hybrid genetic-local search algorithm (GAspLA). Random key numbers are used frequently in genetic algorithms, but it creates additional difficulty when hybrid factors in local search are implemented. We developed algorithms that satisfy the adaptation of results of local search into the genetic algorithms with minimum relocation operation of genes' random key numbers. This is the second contribution of the paper. The third contribution of this paper is three developed new MIP models which are making splitting and scheduling simultaneously. The fourth contribution of this paper is implementation of the GAspLAMIP. This implementation let us verify the optimality of GAspLA for the studied combinations. The proposed methods are tested on a set of problems taken from the literature and the results validate the effectiveness of the proposed algorithms. PMID:24977204

Model validations for low-global warming potential refrigerants in mini-split air-conditioning units

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

Shen, Bo; Shrestha, Som; Abdelaziz, Omar

To identify low GWP (global warming potential) refrigerants to replace R-22 and R-410A, extensive experimental evaluations were conducted for multiple candidates of refrigerant at the standard test conditions and at high-ambient conditions with outdoor temperature varying from 27.8 C to 55.0 C.. In the study, R-22 was compared to propane (R-290), DR-3, ARM-20B, N-20B and R-444B in a mini-split air conditioning unit originally designed for R-22; R-410A was compared to R-32, DR-55, ARM-71A, L41-2 (R-447A) in a mini-split unit designed for R-410A. To reveal physics behind the measured performance results, thermodynamic properties of the alternative refrigerants were analysed. In addition,more » the experimental data was used to calibrate a physics-based equipment model, i.e. ORNL Heat Pump Design Model (HPDM). The calibrated model translated the experimental results to key calculated parameters, i.e. compressor efficiencies, refrigerant side two-phase heat transfer coefficients, corresponding to each refrigerant. As a result, these calculated values provide scientific insights on the performance of the alternative refrigerants and are useful for other applications beyond mini-split air conditioning units.« less

Split Bregman multicoil accelerated reconstruction technique: A new framework for rapid reconstruction of cardiac perfusion MRI

PubMed Central

Kamesh Iyer, Srikant; Tasdizen, Tolga; Likhite, Devavrat; DiBella, Edward

2016-01-01

Purpose: Rapid reconstruction of undersampled multicoil MRI data with iterative constrained reconstruction method is a challenge. The authors sought to develop a new substitution based variable splitting algorithm for faster reconstruction of multicoil cardiac perfusion MRI data. Methods: The new method, split Bregman multicoil accelerated reconstruction technique (SMART), uses a combination of split Bregman based variable splitting and iterative reweighting techniques to achieve fast convergence. Total variation constraints are used along the spatial and temporal dimensions. The method is tested on nine ECG-gated dog perfusion datasets, acquired with a 30-ray golden ratio radial sampling pattern and ten ungated human perfusion datasets, acquired with a 24-ray golden ratio radial sampling pattern. Image quality and reconstruction speed are evaluated and compared to a gradient descent (GD) implementation and to multicoil k-t SLR, a reconstruction technique that uses a combination of sparsity and low rank constraints. Results: Comparisons based on blur metric and visual inspection showed that SMART images had lower blur and better texture as compared to the GD implementation. On average, the GD based images had an ∼18% higher blur metric as compared to SMART images. Reconstruction of dynamic contrast enhanced (DCE) cardiac perfusion images using the SMART method was ∼6 times faster than standard gradient descent methods. k-t SLR and SMART produced images with comparable image quality, though SMART was ∼6.8 times faster than k-t SLR. Conclusions: The SMART method is a promising approach to reconstruct good quality multicoil images from undersampled DCE cardiac perfusion data rapidly. PMID:27036592

[Development of patient-reported outcome scale for myasthenia gravis: a psychometric test].

PubMed

Chen, Xin-lin; Liu, Feng-bin; Guo, Li; Liu, Xiao-bin

2010-02-01

To investigate the scientificity of patient-reported outcome (PRO) scale for myasthenia gravis (MG), which was used to evaluate the clinical effects of traditional Chinese and Western medicine treatment on MG patients. Psychometric performance of the MG-PRO scale was also expected to be evaluated in this study. A total of 100 MG patients and 100 healthy people were face-to-face interviewed by well-trained investigators, and the data of MG-PRO scale were collected. The classical theory test (CTT) and item response theory (IRT) methods were used to analyze the psychometric performance such as validity, reliability, person separation index (PSI) and differential item functioning (DIF) in the MG-PRO scale. The results of CTT analysis showed that the split-half reliabilities of the MG-PRO scale and each dimension were greater than 0.7. In the analysis of internal consistency of each dimension, the Cronbach's alpha was greater than 0.8. Each facet had greater correlation with its dimension than the other dimensions. Four principal components were extracted by exploratory factor analysis, which represented all dimensions of the scale, and the cumulative variance was 55.54%. The scores of each of the 8 facets between MG patients and healthy people were different (P<0.01). The results of IRT showed that the PSI of each model was greater than 0.8, and all items did not have uniform DIF and non-uniform DIF. The MG-PRO scale reflects the definition and connotation of quality of life and contains special issues of MG patients as well, and shows good reliability (split-half reliability, Cronbach's alpha), validity (content validity, construct validity, discriminate validity) from the results of CTT, and good psychometric performance from the results of IRT.

Development and Validation of an Algorithm to Identify Patients with Multiple Myeloma Using Administrative Claims Data.

PubMed

Princic, Nicole; Gregory, Chris; Willson, Tina; Mahue, Maya; Felici, Diana; Werther, Winifred; Lenhart, Gregory; Foley, Kathleen A

2016-01-01

The objective was to expand on prior work by developing and validating a new algorithm to identify multiple myeloma (MM) patients in administrative claims. Two files were constructed to select MM cases from MarketScan Oncology Electronic Medical Records (EMR) and controls from the MarketScan Primary Care EMR during January 1, 2000-March 31, 2014. Patients were linked to MarketScan claims databases, and files were merged. Eligible cases were age ≥18, had a diagnosis and visit for MM in the Oncology EMR, and were continuously enrolled in claims for ≥90 days preceding and ≥30 days after diagnosis. Controls were age ≥18, had ≥12 months of overlap in claims enrollment (observation period) in the Primary Care EMR and ≥1 claim with an ICD-9-CM diagnosis code of MM (203.0×) during that time. Controls were excluded if they had chemotherapy; stem cell transplant; or text documentation of MM in the EMR during the observation period. A split sample was used to develop and validate algorithms. A maximum of 180 days prior to and following each MM diagnosis was used to identify events in the diagnostic process. Of 20 algorithms explored, the baseline algorithm of 2 MM diagnoses and the 3 best performing were validated. Values for sensitivity, specificity, and positive predictive value (PPV) were calculated. Three claims-based algorithms were validated with ~10% improvement in PPV (87-94%) over prior work (81%) and the baseline algorithm (76%) and can be considered for future research. Consistent with prior work, it was found that MM diagnoses before and after tests were needed.

Effect of Stress and Saturation on Shear Wave Anisotropy: Laboratory Observations Using Laser Doppler Interferometry

NASA Astrophysics Data System (ADS)

Lebedev, M.; Collet, O.; Bona, A.; Gurevich, B.

2015-12-01

Estimations of hydrocarbon and water resources as well as reservoir management during production are the main challenges facing the resource recovery industry nowadays. The recently discovered reservoirs are not only deep but they are also located in complicated geological formations. Hence, the effect of anisotropy on reservoir imaging becomes significant. Shear wave (S-wave) splitting has been observed in the field and laboratory experiments for decades. Despite the fact that S-wave splitting is widely used for evaluation of subsurface anisotropy, the effects of stresses as well fluid saturation on anisotropy have not been understood in detail. In this paper we present the laboratory study of the effect of stress and saturation on S-wave splitting for a Bentheim sandstone sample. The cubic sample (50mm3), porosity 22%, density 1890kg/m3) was placed into a true-triaxial cell. The sample was subjected to several combinations of stresses varying from 0 to 10MPa and applied to the sample in two directions (X and Y), while no stress was applied to the sample in the Z-direction. The sample's bedding was nearly oriented parallel to Y-Z plane. The ultrasonic S-waves were exited at a frequency of 0.5MHz by a piezoelectric transducer and were propagating in the Z-direction. Upon wave arrival onto the free surface the displacement of the surface was monitored by a Laser Doppler interferometer. Hodograms of the central point of the dry sample (Fig. 1) demonstrate how S-wave polarizations for both "fast" and "slow" S-waves change when increasing the stress in the X direction, while the stress in direction Y is kept constant at 3 MPa. Polarization of the fast S wave is shifted towards the X-axis (axis of the maximum stress). While both S-wave velocities increase with stress, the anisotropy level remains the same. No shift of polarization of fast wave was observed when the stress along the Y-axis was kept at 3 MPa, while the stress along the X-axis was increasing. However, in that case, S-wave splitting is more prominent. The fast S-wave velocity is increasing with the stress increase while the slow S-wave velocity starts decreasing after 5MPa, indicating possible cracks opening in the Y-direction. Interestingly no change in anisotropy was observed for the water-saturated sample.

Tablet splitting and weight uniformity of half-tablets of 4 medications in pharmacy practice.

PubMed

Tahaineh, Linda M; Gharaibeh, Shadi F

2012-08-01

Tablet splitting is a common practice for multiple reasons including cost savings; however, it does not necessarily result in weight-uniform half-tablets. To determine weight uniformity of half-tablets resulting from splitting 4 products available in the Jordanian market and investigate the effect of tablet characteristics on weight uniformity of half-tablets. Ten random tablets each of warfarin 5 mg, digoxin 0.25 mg, phenobarbital 30 mg, and prednisolone 5 mg were weighed and split by 6 PharmD students using a knife. The resulting half-tablets were weighed and evaluated for weight uniformity. Other relevant physical characteristics of the 4 products were measured. The average tablet hardness of the sampled tablets ranged from 40.3 N to 68.9 N. Digoxin, phenobarbital, and prednisolone half-tablets failed the weight uniformity test; however, warfarin half-tablets passed. Digoxin, warfarin, and phenobarbital tablets had a score line and warfarin tablets had the deepest score line of 0.81 mm. Splitting warfarin tablets produces weight-uniform half-tablets that may possibly be attributed to the hardness and the presence of a deep score line. Digoxin, phenobarbital, and prednisolone tablet splitting produces highly weight variable half-tablets. This can be of clinical significance in the case of the narrow therapeutic index medication digoxin.

Development of a predictive limited sampling strategy for estimation of mycophenolic acid area under the concentration time curve in patients receiving concomitant sirolimus or cyclosporine.

PubMed

Figurski, Michal J; Nawrocki, Artur; Pescovitz, Mark D; Bouw, Rene; Shaw, Leslie M

2008-08-01

Limited sampling strategies for estimation of the area under the concentration time curve (AUC) for mycophenolic acid (MPA) co-administered with sirolimus (SRL) have not been previously evaluated. The authors developed and validated 68 regression models for estimation of MPA AUC for two groups of patients, one with concomitant SRL (n = 24) and the second with concomitant cyclosporine (n=14), using various combinations of time points between 0 and 4 hours after drug administration. To provide as robust a model as possible, a dataset-splitting method similar to a bootstrap was used. In this method, the dataset was randomly split in half 100 times. Each time, one half of the data was used to estimate the equation coefficients, and the other half was used to test and validate the models. Final models were obtained by calculating the median values of the coefficients. Substantial differences were found in the pharmacokinetics of MPA between these groups. The mean MPA AUC as well as the standard deviation was much greater in the SRL group, 56.4 +/- 23.5 mg.h/L, compared with 30.4 +/- 11.0 mg.h/L in the cyclosporine group (P < 0.001). Mean maximum concentration was also greater in the SRL group: 16.4 +/- 7.7 mg/L versus 11.7 +/- 7.1mg/L (P < 0.005). The second absorption peak in the pharmacokinetic profile, presumed to result from enterohepatic recycling of glucuronide MPA, was observed in 70% of the profiles in the SRL group and in 35% of profiles from the cyclosporine group. Substantial differences in the predictive performance of the regression models, based on the same time points, were observed between the two groups. The best model for the SRL group was based on 0 (trough) and 40 minutes and 4 hour time points with R2, root mean squared error, and predictive performance values of 0.82, 10.0, and 78%, respectively. In the cyclosporine group, the best model was 0 and 40 minutes and 2 hours, with R2, RMSE, and predictive performance values of 0.86, 4.1, and 83%, respectively. The model with 2 hours as the last time point is also recommended for the SRL group for practical reasons, with the above parameters of 0.77, 11.3, and 69%, respectively.

Comparison of STR profiling from low template DNA extracts with and without the consensus profiling method

PubMed Central

2012-01-01

Background The consensus profiling method was introduced to overcome the exaggerated stochastic effects associated with low copy number DNA typing. However, little empirical evidence has been provided which shows that a consensus profile, derived from dividing a sample into separate aliquots and including only alleles seen at least twice, gives the most informative profile, compared to a profile obtained by amplifying the entire low template DNA extract in one reaction. Therefore, this study aimed to investigate the quality of consensus profiles compared to profiles obtained using the whole low template extract for amplification. Methods A total of 100 pg and 25 pg DNA samples were amplified with the PowerPlex® ESI 16 Kits using 30 or 34 PCR cycles. A total of 100 pg and 25 pg DNA samples were then divided into three aliquots for a 34-cycle PCR and a consensus profile derived that included alleles that appeared in at least two of the replicates. Profiles from the non-split samples were compared to the consensus profiles focusing on peak heights, allele drop out, locus drop out and allele drop in. Results Performing DNA profiling on non-split extracts produced profiles with a higher percentage of correct loci compared to the consensus profiling technique. Consensus profiling did eliminate any spurious alleles from the final profile. However, there was a notable increase in allele and locus drop out when a LTDNA sample was divided prior to amplification. Conclusions The loss of information that occurs when a sample is split for amplification indicates that consensus profiling may not be producing the most informative DNA profile for samples where the template amount is limited. PMID:22748106

A compact 5.5 GHz band-rejected UWB antenna using complementary split ring resonators.

PubMed

Islam, M M; Faruque, M R I; Islam, M T

2014-01-01

A band-removal property employing microwave frequencies using complementary split ring resonators (CSRRs) is applied to design a compact UWB antenna wishing for the rejection of some frequency band, which is meanwhile exercised by the existing wireless applications. The reported antenna comprises optimization of a circular radiating patch, in which slotted complementary SRRs are implanted. It is printed on low dielectric FR4 substrate material fed by a partial ground plane and a microstrip line. Validated results exhibit that the reported antenna shows a wide bandwidth covering from 3.45 to more than 12 GHz, with a compact dimension of 22 × 26 mm(2), and VSWR < 2, observing band elimination of 5.5 GHz WLAN band.

Personality assessment inventory internalizing and externalizing structure in veterans with posttraumatic stress disorder: associations with aggression.

PubMed

Van Voorhees, Elizabeth E; Dennis, Paul A; Elbogen, Eric B; Clancy, Carolina P; Hertzberg, Michael A; Beckham, Jean C; Calhoun, Patrick S

2014-01-01

Posttraumatic stress disorder (PTSD) is associated with aggressive behavior in veterans, and difficulty controlling aggressive urges has been identified as a primary postdeployment readjustment concern. Yet only a fraction of veterans with PTSD commit violent acts. The goals of this study were to (1) examine the higher-order factor structure of Personality Assessment Inventory (PAI) scales in a sample of U.S. military veterans seeking treatment for PTSD; and (2) to evaluate the incremental validity of higher-order latent factors of the PAI over PTSD symptom severity in modeling aggression. The study sample included male U.S. Vietnam (n = 433) and Iraq/Afghanistan (n = 165) veterans who were seeking treatment for PTSD at an outpatient Veterans Affairs (VA) clinic. Measures included the Clinician Administered PTSD Scale, the PAI, and the Conflict Tactics Scale. The sample was randomly split into two equal subsamples (n's = 299) to allow for cross-validation of statistically derived factors. Parallel analysis, variable clustering analysis, and confirmatory factor analyses were used to evaluate the factor structure, and regression was used to examine the association of factor scores with self-reports of aggression over the past year. Three factors were identified: internalizing, externalizing, and substance abuse. Externalizing explained unique variance in aggression beyond PTSD symptom severity and demographic factors, while internalizing and substance abuse did not. Service era was unrelated to reports of aggression. The constructs of internalizing versus externalizing dimensions of PTSD may have utility in identifying characteristics of combat veterans in the greatest need of treatment to help manage aggressive urges. Published 2014 Wiley Periodicals, Inc.

Mapping seabed sediments: Comparison of manual, geostatistical, object-based image analysis and machine learning approaches

NASA Astrophysics Data System (ADS)

Diesing, Markus; Green, Sophie L.; Stephens, David; Lark, R. Murray; Stewart, Heather A.; Dove, Dayton

2014-08-01

Marine spatial planning and conservation need underpinning with sufficiently detailed and accurate seabed substrate and habitat maps. Although multibeam echosounders enable us to map the seabed with high resolution and spatial accuracy, there is still a lack of fit-for-purpose seabed maps. This is due to the high costs involved in carrying out systematic seabed mapping programmes and the fact that the development of validated, repeatable, quantitative and objective methods of swath acoustic data interpretation is still in its infancy. We compared a wide spectrum of approaches including manual interpretation, geostatistics, object-based image analysis and machine-learning to gain further insights into the accuracy and comparability of acoustic data interpretation approaches based on multibeam echosounder data (bathymetry, backscatter and derivatives) and seabed samples with the aim to derive seabed substrate maps. Sample data were split into a training and validation data set to allow us to carry out an accuracy assessment. Overall thematic classification accuracy ranged from 67% to 76% and Cohen's kappa varied between 0.34 and 0.52. However, these differences were not statistically significant at the 5% level. Misclassifications were mainly associated with uncommon classes, which were rarely sampled. Map outputs were between 68% and 87% identical. To improve classification accuracy in seabed mapping, we suggest that more studies on the effects of factors affecting the classification performance as well as comparative studies testing the performance of different approaches need to be carried out with a view to developing guidelines for selecting an appropriate method for a given dataset. In the meantime, classification accuracy might be improved by combining different techniques to hybrid approaches and multi-method ensembles.

Kinetics and reaction coordinates of the reassembly of protein fragments via forward flux sampling.

PubMed

Borrero, Ernesto E; Contreras Martínez, Lydia M; DeLisa, Matthew P; Escobedo, Fernando A

2010-05-19

We studied the mechanism of the reassembly and folding process of two fragments of a split lattice protein by using forward flux sampling (FFS). Our results confirmed previous thermodynamics and kinetics analyses that suggested that the disruption of the critical core (of an unsplit protein that folds by a nucleation mechanism) plays a key role in the reassembly mechanism of the split system. For several split systems derived from a parent 48-mer model, we estimated the reaction coordinates in terms of collective variables by using the FFS least-square estimation method and found that the reassembly transition is best described by a combination of the total number of native contacts, the number of interchain native contacts, and the total conformational energy of the split system. We also analyzed the transition path ensemble obtained from FFS simulations using the estimated reaction coordinates as order parameters to identify the microscopic features that differentiate the reassembly of the different split systems studied. We found that in the fastest folding split system, a balanced distribution of the original-core amino acids (of the unsplit system) between protein fragments propitiates interchain interactions at early stages of the folding process. Only this system exhibits a different reassembly mechanism from that of the unsplit protein, involving the formation of a different folding nucleus. In the slowest folding system, the concentration of the folding nucleus in one fragment causes its early prefolding, whereas the second fragment tends to remain as a detached random coil. We also show that the reassembly rate can be either increased or decreased by tuning interchain cooperativeness via the introduction of a single point mutation that either strengthens or weakens one of the native interchain contacts (prevalent in the transition state ensemble). Copyright (c) 2010 Biophysical Society. Published by Elsevier Inc. All rights reserved.

The effects of acid leaching on 40Ar/39Ar age dating results using samples from the Walvis Ridge hotspot trail

NASA Astrophysics Data System (ADS)

Klath, J. F.; Koppers, A. A.; Heaton, D. E.; Schnur, S.

2013-12-01

In this study we systematically explore how acid leaching can be used to reduce the negative effects of seawater alteration on the 40Ar/39Ar age dating of submarine basalts. Koppers et al (2000) showed that acid leaching of groundmass samples generated more consistent ages as well as ages more concordant with phenocrystic mineral phases, compared to samples that were left untreated. By studying the effects of progressively increasing the strength and length of acid treatment, we will show how acid leaching of groundmass separates reduces alteration while leaving the initial eruption signature intact. Samples were chosen from the Walvis ridge hotspot trail in the southeast Atlantic. Three samples were selected based on degree and style of alteration. Two samples (basalt and basaltic andesite) appear highly altered in thin section. The basalt contains diffuse iddingsite alteration that is pervasive throughout the groundmass. The basaltic andesite displays focused secondary mineral phases within and around abundant vesicles. The third sample, a trachyte, shows relatively minor degrees of alteration in thin section. These groundmass separates were divided into four splits and treated with a progressively stronger acid and for longer duration. One split from each rock was left untreated to act as a baseline. Of the other three splits from each sample, one was treated with a mild leach (1N HCl and 1N HNO3), one a strong leach (1N HCl, 1N HNO3, 6N HCl, and 3N HNO3), and lastly the strong leach performed twice. The samples were then handpicked to remove any remaining visible alteration. The untreated samples were picked as well, removing the most distinctly altered grains. All splits were analyzed by electron microprobe, x-ray fluorescence (XRF) and the incremental heating 40Ar/39Ar dating method. We will report on the results of an image analysis of microprobe backscatter images and elemental maps taken of individual groundmass grains. This analysis will show the location of alteration within the groundmass and how it is changing as acid leaching strength and duration progresses. We will discuss bulk composition comparisons as well as how depletions and enrichments vary amongst major and trace elements. Lastly, we will report 40Ar/39Ar step heating results, in particular K/Ca ratios and age spectra, to better understand the effect of leaching strength on the effective removal of groundmass alteration during 40Ar/39Ar age dating.

Experimental Validation of the Half-Length Force Concept Inventory

ERIC Educational Resources Information Center

Han, Jing; Koenig, Kathleen; Cui, Lili; Fritchman, Joseph; Li, Dan; Sun, Wanyi; Fu, Zhao; Bao, Lei

2016-01-01

In a recent study, the 30-question Force Concept Inventory (FCI) was theoretically split into two 14-question "half-length" tests (HFCIs) covering the same set of concepts and producing mean scores that can be equated to those of the original FCI. The HFCIs require less administration time and reduce test-retest issues when different…

A Preliminary Study for a New Model of Sense of Community

ERIC Educational Resources Information Center

Tartaglia, Stefano

2006-01-01

Although Sense of Community (SOC) is usually defined as a multidimensional construct, most SOC scales are unidimensional. To reduce the split between theory and empirical research, the present work identifies a multifactor structure for the Italian Sense of Community Scale (ISCS) that has already been validated as a unitary index of SOC. This…

Standardization of the Gordon Primary Measures of Music Audiation in Greece

ERIC Educational Resources Information Center

Stamou, Lelouda; Schmidt, Charles P.; Humphreys, Jere T.

2010-01-01

The purpose of this study was to standardize the Primary Measures of Music Audiation in Greece ( N = 1,188). Split-halves reliability was acceptable across grade levels (K through 3) for the Tonal and Rhythm subtests, but test-retest reliability was generally unacceptable, especially for the Rhythm subtest. Concurrent validity was mixed, with…

Development and Validation of a Questionnaire to Assess Carbohydrate and Insulin-Dosing Knowledge in Youth With Type 1 Diabetes

PubMed Central

Koontz, Michaela B.; Cuttler, Leona; Palmert, Mark R.; O'Riordan, MaryAnn; Borawski, Elaine A.; McConnell, Judy; Kern, Elizabeth O.

2010-01-01

OBJECTIVE The American Diabetes Association advocates insulin regimens for youth with type 1 diabetes that involve adjusting insulin dose based on carbohydrate intake and blood glucose level. Implementing these regimens requires knowledge about carbohydrate content of foods and subsequent calculations of insulin dose, skills that may be difficult to gauge in practice. Therefore, we sought to develop and validate a questionnaire, the PedCarbQuiz (PCQ), to assess carbohydrate and insulin-dosing knowledge in youth with type 1 diabetes. RESEARCH DESIGN AND METHODS After development by an expert panel, the PCQ was administered to 75 youth with type 1 diabetes or their parents. Reliability was assessed by Cronbach α and split-half testing. To assess validity, scores were correlated with A1C, expert assessments, parent educational level, and complexity of insulin regimen. RESULTS PCQ mean score was 87 ± 9.7% (range 42–98%). Cronbach α was 0.88, and correlation of split halves was 0.59 (P < 0.0001). Higher PCQ scores correlated significantly with lower A1C (r = −0.29, P = 0.01) and expert assessments (r = 0.56, P < 0.001). Scores were significantly higher in parents with college degrees than in those without (P = 0.01) and in participants with more complex insulin regimens (P = 0.003). CONCLUSIONS The PCQ is a novel, easily administered instrument to assess knowledge about carbohydrates and insulin dosing calculations. Initial analyses support the reliability and validity of the PCQ. PMID:20007940

Development and psychometric testing the Health of Body, Mind and Spirit Scale for assessing individuals who have drug abuse histories.

PubMed

Sun, Fan-Ko; Chiang, Chun-Ying; Lu, Chu-Yun; Yu, Pei-Jane; Liao, Tzu-Chiao; Lan, Chu-Mei

2018-03-01

To develop the Health of Body, Mind and Spirit Scale (HBMSS), which was designed to assess drug abusers' health condition. Helping drug abusers to become healthy is important to healthcare professionals. However, no instrument exists to assess drug abusers' state of health. A cross-sectional questionnaire survey was implemented to examine the validity of the HBMSS. Data were collected from 2015-2016 at one drug abuse prevention centre in Taiwan. Participants (N = 320) who had abused drugs were invited to complete a preliminary 64-item version of the HBMSS. An item analysis, criterion-related validity analysis (using the Relapse Prediction Scale [RPS] score), split-half reliability testing and confirmatory factor analysis (CFA) were conducted to examine the psychometric properties of the HBMSS. The final version of the HBMSS contained 15 items that were divided into three subscales: the health of the body, mind and spirit. Cronbach's α and split-half reliability coefficients were all above .85. The factor loading of each item was between .74-.95. The HBMSS had satisfactory criterion-related validity with the RPS score (r = -.50, p < .001). A second-order CFA was conducted on the HBMSS. The fit indexes were good, χ 2  = 184.060, df = 94, χ 2 /df = 1.958 (p = .000). The entire HBMSS and the subscales had satisfactory reliability and validity. Healthcare professionals could use the HBMSS to evaluate the condition of the health of individuals with a drug abuse history. © 2017 John Wiley & Sons Ltd.

Monte Carlo based modelling approach for designing and predicting cytotoxicity of 2-phenylindole derivatives against breast cancer cell line MCF7.

PubMed

Gaikwad, Ruchi; Ghorai, Soumajit; Amin, Sk Abdul; Adhikari, Nilanjan; Patel, Tarun; Das, Kalpataru; Jha, Tarun; Gayen, Shovanlal

2018-06-01

Breast cancer is one of the leading causes of cancers among the variety of cancers in woman all over the world. Compounds with phenylindole scaffold were found to execute promising cytotoxicity against breast cancer cell line MCF7. In the present study, a Monte Carlo based QSAR analysis was performed on a dataset containing 102 phenylindoles in order to accelerate the efforts to find out better cytotoxic phenylindoles against MCF7 cell line. The statistical qualities of the generated models were found to be quite good as far as the internal and external validation were concerned. The best models from each split (Split 1: R 2  = 0.6944, Q 2  = 0.6495; Split 2: R 2  = 0.8202, Q 2  = 0.7998; Split 3: R 2  = 0.8603, Q 2  = 0.8357) for the test set were selected and Y-scrambling test and applicability domain analysis were also performed to ensure the robustness of these models. Among these models, model from split 3 obtained by using hybrid descriptors (combination of SMILES and HSG with 0 ECk connectivity) was used to identify and classify the structural attributes as promoters as well as hinderers of cytotoxicity for these 2-phenylindole derivatives. Results from the analysis were further used to design and predict some probable new 2-phenylindole derivatives having promising cytotoxicity (IC 50  < 55 nM) against MCF7. Copyright © 2018 Elsevier Ltd. All rights reserved.

Comparing near-infrared conventional diffuse reflectance spectroscopy and hyperspectral imaging for determination of the bulk properties of solid samples by multivariate regression: determination of Mooney viscosity and plasticity indices of natural rubber.

PubMed

Juliano da Silva, Carlos; Pasquini, Celio

2015-01-21

Conventional reflectance spectroscopy (NIRS) and hyperspectral imaging (HI) in the near-infrared region (1000-2500 nm) are evaluated and compared, using, as the case study, the determination of relevant properties related to the quality of natural rubber. Mooney viscosity (MV) and plasticity indices (PI) (PI0 - original plasticity, PI30 - plasticity after accelerated aging, and PRI - the plasticity retention index after accelerated aging) of rubber were determined using multivariate regression models. Two hundred and eighty six samples of rubber were measured using conventional and hyperspectral near-infrared imaging reflectance instruments in the range of 1000-2500 nm. The sample set was split into regression (n = 191) and external validation (n = 95) sub-sets. Three instruments were employed for data acquisition: a line scanning hyperspectral camera and two conventional FT-NIR spectrometers. Sample heterogeneity was evaluated using hyperspectral images obtained with a resolution of 150 × 150 μm and principal component analysis. The probed sample area (5 cm(2); 24,000 pixels) to achieve representativeness was found to be equivalent to the average of 6 spectra for a 1 cm diameter probing circular window of one FT-NIR instrument. The other spectrophotometer can probe the whole sample in only one measurement. The results show that the rubber properties can be determined with very similar accuracy and precision by Partial Least Square (PLS) regression models regardless of whether HI-NIR or conventional FT-NIR produce the spectral datasets. The best Root Mean Square Errors of Prediction (RMSEPs) of external validation for MV, PI0, PI30, and PRI were 4.3, 1.8, 3.4, and 5.3%, respectively. Though the quantitative results provided by the three instruments can be considered equivalent, the hyperspectral imaging instrument presents a number of advantages, being about 6 times faster than conventional bulk spectrometers, producing robust spectral data by ensuring sample representativeness, and minimizing the effect of the presence of contaminants.

An Overview of Importance Splitting for Rare Event Simulation

ERIC Educational Resources Information Center

Morio, Jerome; Pastel, Rudy; Le Gland, Francois

2010-01-01

Monte Carlo simulations are a classical tool to analyse physical systems. When unlikely events are to be simulated, the importance sampling technique is often used instead of Monte Carlo. Importance sampling has some drawbacks when the problem dimensionality is high or when the optimal importance sampling density is complex to obtain. In this…

Selected laboratory evaluations of the whole-water sample-splitting capabilities of a prototype fourteen-liter Teflon churn splitter

USGS Publications Warehouse

Horowitz, A.J.; Smith, J.J.; Elrick, K.A.

2001-01-01

A prototype 14-L Teflon? churn splitter was evaluated for whole-water sample-splitting capabilities over a range of sediment concentratons and grain sizes as well as for potential chemical contamination from both organic and inorganic constituents. These evaluations represent a 'best-case' scenario because they were performed in the controlled environment of a laboratory, and used monomineralic silica sand slurries of known concentration made up in deionized water. Further, all splitting was performed by a single operator, and all the requisite concentration analyses were performed by a single laboratory. The prototype Teflon? churn splitter did not appear to supply significant concentrations of either organic or inorganic contaminants at current U.S. Geological Survey (USGS) National Water Quality Laboratory detection and reporting limits when test samples were prepared using current USGS protocols. As with the polyethylene equivalent of the prototype Teflon? churn, the maximum usable whole-water suspended sediment concentration for the prototype churn appears to lie between 1,000 and 10,000 milligrams per liter (mg/L). Further, the maximum grain-size limit appears to lie between 125- and 250-microns (m). Tests to determine the efficacy of the valve baffle indicate that it must be retained to facilitate representative whole-water subsampling.

Split Bregman's optimization method for image construction in compressive sensing

NASA Astrophysics Data System (ADS)

Skinner, D.; Foo, S.; Meyer-Bäse, A.

2014-05-01

The theory of compressive sampling (CS) was reintroduced by Candes, Romberg and Tao, and D. Donoho in 2006. Using a priori knowledge that a signal is sparse, it has been mathematically proven that CS can defY Nyquist sampling theorem. Theoretically, reconstruction of a CS image relies on the minimization and optimization techniques to solve this complex almost NP-complete problem. There are many paths to consider when compressing and reconstructing an image but these methods have remained untested and unclear on natural images, such as underwater sonar images. The goal of this research is to perfectly reconstruct the original sonar image from a sparse signal while maintaining pertinent information, such as mine-like object, in Side-scan sonar (SSS) images. Goldstein and Osher have shown how to use an iterative method to reconstruct the original image through a method called Split Bregman's iteration. This method "decouples" the energies using portions of the energy from both the !1 and !2 norm. Once the energies are split, Bregman iteration is used to solve the unconstrained optimization problem by recursively solving the problems simultaneously. The faster these two steps or energies can be solved then the faster the overall method becomes. While the majority of CS research is still focused on the medical field, this paper will demonstrate the effectiveness of the Split Bregman's methods on sonar images.

Image Reconstruction from Under sampled Fourier Data Using the Polynomial Annihilation Transform

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

Archibald, Richard K.; Gelb, Anne; Platte, Rodrigo

Fourier samples are collected in a variety of applications including magnetic resonance imaging and synthetic aperture radar. The data are typically under-sampled and noisy. In recent years, l 1 regularization has received considerable attention in designing image reconstruction algorithms from under-sampled and noisy Fourier data. The underlying image is assumed to have some sparsity features, that is, some measurable features of the image have sparse representation. The reconstruction algorithm is typically designed to solve a convex optimization problem, which consists of a fidelity term penalized by one or more l 1 regularization terms. The Split Bregman Algorithm provides a fastmore » explicit solution for the case when TV is used for the l1l1 regularization terms. Due to its numerical efficiency, it has been widely adopted for a variety of applications. A well known drawback in using TV as an l 1 regularization term is that the reconstructed image will tend to default to a piecewise constant image. This issue has been addressed in several ways. Recently, the polynomial annihilation edge detection method was used to generate a higher order sparsifying transform, and was coined the “polynomial annihilation (PA) transform.” This paper adapts the Split Bregman Algorithm for the case when the PA transform is used as the l 1 regularization term. In so doing, we achieve a more accurate image reconstruction method from under-sampled and noisy Fourier data. Our new method compares favorably to the TV Split Bregman Algorithm, as well as to the popular TGV combined with shearlet approach.« less

World Trade Center human identification project: experiences with individual body identification cases.

PubMed

Budimlija, Zoran M; Prinz, Mechthild K; Zelson-Mundorff, Amy; Wiersema, Jason; Bartelink, Eric; MacKinnon, Gaille; Nazzaruolo, Bianca L; Estacio, Sheila M; Hennessey, Michael J; Shaler, Robert C

2003-06-01

To present individual body identification efforts, as part of the World Trade Center (WTC) mass disaster identification project. More than 500 samples were tested by using polymerase chain reaction (PCR) amplification and short tandem repeat (STR) typing. The extent to which the remains were fragmented and affected by taphonomic factors complicated the identification project. Anthropologists reviewed 19,000 samples, and detected inconsistencies in 69, which were further split into 239 new cases and re-sampled by DNA specialists. The severity and nature of the disaster required an interdisciplinary effort. DNA profiling of 500 samples was successful in 75% of the cases. All discrepancies, which occurred between bone and tissue samples taken from the same body part, were resolved by re-sampling and re-testing of preferably bone tissue. Anthropologists detected inconsistencies in 69 cases, which were then split into 239 new cases. Out of 125 "split" cases, 65 were excluded from their original case. Of these 65 cases, 37 did not match any profiles in M-FISys, probably because profiles were incomplete or no exemplar for the victim was available. Out of the 60 remains not excluded from their original case, 30 were partial profiles and did not reach the statistical requirement to match their original case, because the population frequency of the DNA profile had to be

Finite element analysis and experiment on high pressure apparatus with split cylinder

NASA Astrophysics Data System (ADS)

Zhao, Liang; Li, Mingzhe; Yang, Yunfei; Wang, Bolong; Li, Yi

2017-07-01

Ultra-high pressure belt-type die was designed with a large sample volume prism cavity and a split cylinder which was divided into eight segments to eliminate circumferential stress. The cylinder of this type die has no cambered surface on inner wall, and the inner hole is a hexagonal prism-type cavity. The divided bodies squeeze with each other, providing the massive support and lateral support effect of the cylinder. Simulation results indicate that the split cylinder with the prism cavity possesses much smaller stress and more uniform stress distribution. The split cylinder with the prism cavity has been shown to bear larger compressive stresses in radial, circumferential and axial directions due to its structure, and tungsten carbide is most effective in pure compression so this type cylinder could bear higher pressure. Experimental results prove that the high pressure apparatus with a prism-type cavity could bear higher pressure. The apparatus with a prism cavity could bear 52.2% more pressure than the belt-type die.

Rashba Interaction and Local Magnetic Moments in a Graphene-BN Heterostructure Intercalated with Au

NASA Astrophysics Data System (ADS)

O'Farrell, E. C. T.; Tan, J. Y.; Yeo, Y.; Koon, G. K. W.; Ã-zyilmaz, B.; Watanabe, K.; Taniguchi, T.

2016-08-01

We intercalate a van der Waals heterostructure of graphene and hexagonal boron nitride with Au, by encapsulation, and show that the Au at the interface is two dimensional. Charge transfer upon current annealing indicates the redistribution of the Au and induces splitting of the graphene band structure. The effect of an in-plane magnetic field confirms that the splitting is due to spin splitting and that the spin polarization is in the plane, characteristic of a Rashba interaction with a magnitude of approximately 25 meV. Consistent with the presence of an intrinsic interfacial electric field we show that the splitting can be enhanced by an applied displacement field in dual gated samples. A giant negative magnetoresistance, up to 75%, and a field induced anomalous Hall effect at magnetic fields <1 T are observed. These demonstrate that the hybridized Au has a magnetic moment and suggests the proximity to the formation of a collective magnetic phase. These effects persist close to room temperature.

Dynamic adaptive chemistry with operator splitting schemes for reactive flow simulations

NASA Astrophysics Data System (ADS)

Ren, Zhuyin; Xu, Chao; Lu, Tianfeng; Singer, Michael A.

2014-04-01

A numerical technique that uses dynamic adaptive chemistry (DAC) with operator splitting schemes to solve the equations governing reactive flows is developed and demonstrated. Strang-based splitting schemes are used to separate the governing equations into transport fractional substeps and chemical reaction fractional substeps. The DAC method expedites the numerical integration of reaction fractional substeps by using locally valid skeletal mechanisms that are obtained using the directed relation graph (DRG) reduction method to eliminate unimportant species and reactions from the full mechanism. Second-order temporal accuracy of the Strang-based splitting schemes with DAC is demonstrated on one-dimensional, unsteady, freely-propagating, premixed methane/air laminar flames with detailed chemical kinetics and realistic transport. The use of DAC dramatically reduces the CPU time required to perform the simulation, and there is minimal impact on solution accuracy. It is shown that with DAC the starting species and resulting skeletal mechanisms strongly depend on the local composition in the flames. In addition, the number of retained species may be significant only near the flame front region where chemical reactions are significant. For the one-dimensional methane/air flame considered, speed-up factors of three and five are achieved over the entire simulation for GRI-Mech 3.0 and USC-Mech II, respectively. Greater speed-up factors are expected for larger chemical kinetics mechanisms.

A New Tool for Nutrition App Quality Evaluation (AQEL): Development, Validation, and Reliability Testing.

PubMed

DiFilippo, Kristen Nicole; Huang, Wenhao; Chapman-Novakofski, Karen M

2017-10-27

The extensive availability and increasing use of mobile apps for nutrition-based health interventions makes evaluation of the quality of these apps crucial for integration of apps into nutritional counseling. The goal of this research was the development, validation, and reliability testing of the app quality evaluation (AQEL) tool, an instrument for evaluating apps' educational quality and technical functionality. Items for evaluating app quality were adapted from website evaluations, with additional items added to evaluate the specific characteristics of apps, resulting in 79 initial items. Expert panels of nutrition and technology professionals and app users reviewed items for face and content validation. After recommended revisions, nutrition experts completed a second AQEL review to ensure clarity. On the basis of 150 sets of responses using the revised AQEL, principal component analysis was completed, reducing AQEL into 5 factors that underwent reliability testing, including internal consistency, split-half reliability, test-retest reliability, and interrater reliability (IRR). Two additional modifiable constructs for evaluating apps based on the age and needs of the target audience as selected by the evaluator were also tested for construct reliability. IRR testing using intraclass correlations (ICC) with all 7 constructs was conducted, with 15 dietitians evaluating one app. Development and validation resulted in the 51-item AQEL. These were reduced to 25 items in 5 factors after principal component analysis, plus 9 modifiable items in two constructs that were not included in principal component analysis. Internal consistency and split-half reliability of the following constructs derived from principal components analysis was good (Cronbach alpha >.80, Spearman-Brown coefficient >.80): behavior change potential, support of knowledge acquisition, app function, and skill development. App purpose split half-reliability was .65. Test-retest reliability showed no significant change over time (P>.05) for all but skill development (P=.001). Construct reliability was good for items assessing age appropriateness of apps for children, teens, and a general audience. In addition, construct reliability was acceptable for assessing app appropriateness for various target audiences (Cronbach alpha >.70). For the 5 main factors, ICC (1,k) was >.80, with a P value of <.05. When 15 nutrition professionals evaluated one app, ICC (2,15) was .98, with a P value of <.001 for all 7 constructs when the modifiable items were specified for adults seeking weight loss support. Our preliminary effort shows that AQEL is a valid, reliable instrument for evaluating nutrition apps' qualities for clinical interventions by nutrition clinicians, educators, and researchers. Further efforts in validating AQEL in various contexts are needed. ©Kristen Nicole DiFilippo, Wenhao Huang, Karen M. Chapman-Novakofski. Originally published in JMIR Mhealth and Uhealth (http://mhealth.jmir.org), 27.10.2017.

Prediction of five-year all-cause mortality in Chinese patients with type 2 diabetes mellitus - A population-based retrospective cohort study.

PubMed

Wan, Eric Yuk Fai; Fong, Daniel Yee Tak; Fung, Colman Siu Cheung; Yu, Esther Yee Tak; Chin, Weng Yee; Chan, Anca Ka Chun; Lam, Cindy Lo Kuen

2017-06-01

This study aimed to develop and validate an all-cause mortality risk prediction model for Chinese primary care patients with type 2 diabetes mellitus(T2DM) in Hong Kong. A population-based retrospective cohort study was conducted on 132,462 Chinese patients who had received public primary care services during 2010. Each gender sample was randomly split on a 2:1 basis into derivation and validation cohorts and was followed-up for a median period of 5years. Gender-specific mortality risk prediction models showing the interaction effect between predictors and age were derived using Cox proportional hazards regression with forward stepwise approach. Developed models were compared with pre-existing models by Harrell's C-statistic and calibration plot using validation cohort. Common predictors of increased mortality risk in both genders included: age; smoking habit; diabetes duration; use of anti-hypertensive agents, insulin and lipid-lowering drugs; body mass index; hemoglobin A1c; systolic blood pressure(BP); total cholesterol to high-density lipoprotein-cholesterol ratio; urine albumin to creatinine ratio(urine ACR); and estimated glomerular filtration rate(eGFR). Prediction models showed better discrimination with Harrell"'s C-statistics of 0.768(males) and 0.782(females) and calibration power from the plots than previously established models. Our newly developed gender-specific models provide a more accurate predicted 5-year mortality risk for Chinese diabetic patients than other established models. Copyright © 2017 Elsevier Inc. All rights reserved.

An Empirical Study of Re-sampling Techniques as a Method for Improving Error Estimates in Split-plot Designs

DTIC Science & Technology

2010-03-01

sufficient replications often lead to models that lack precision in error estimation and thus imprecision in corresponding conclusions. This work develops...v Preface This work is dedicated to all who gave and continue to give in order for me to achieve some semblance of success. Benjamin M. Lee vi...develop, examine and test methodologies for an- alyzing test results from split-plot designs. In particular, this work determines the applicability

Observations of cavity polaritons in one-dimensional photonic crystals containing a liquid-crystalline semiconductor based on perylene bisimide units

NASA Astrophysics Data System (ADS)

Sakata, T.; Suzuki, M.; Yamamoto, T.; Nakanishi, S.; Funahashi, M.; Tsurumachi, N.

2017-10-01

We investigated the optical transmission properties of one-dimensional photonic crystal (1D-PC) microcavity structures containing the liquid-crystalline (LC) perylene tetracarboxylic bisimide (PTCBI) derivative. We fabricated the microcavity structures for this study by two different methods and observed the cavity polaritons successfully in both samples. For one sample, since the PTCBI molecules were aligned in the cavity layer of the 1D-PC by utilizing a friction transfer method, vacuum Rabi splitting energy was strongly dependent on the polarization of the incident light produced by the peculiar optical features of the LC organic semiconductor. For the other sample, we did not utilize the friction transfer method and did not observe such polarization dependence. However, we did observe a relatively large Rabi splitting energy of 187 meV, probably due to the improvement of optical confinement effect.

Euler flow predictions for an oscillating cascade using a high resolution wave-split scheme

NASA Technical Reports Server (NTRS)

Huff, Dennis L.; Swafford, Timothy W.; Reddy, T. S. R.

1991-01-01

A compressible flow code that can predict the nonlinear unsteady aerodynamics associated with transonic flows over oscillating cascades is developed and validated. The code solves the two dimensional, unsteady Euler equations using a time-marching, flux-difference splitting scheme. The unsteady pressures and forces can be determined for arbitrary input motions, although only harmonic pitching and plunging motions are addressed. The code solves the flow equations on a H-grid which is allowed to deform with the airfoil motion. Predictions are presented for both flat plate cascades and loaded airfoil cascades. Results are compared to flat plate theory and experimental data. Predictions are also presented for several oscillating cascades with strong normal shocks where the pitching amplitudes, cascade geometry and interblade phase angles are varied to investigate nonlinear behavior.

Imaging simulation of active EO-camera

NASA Astrophysics Data System (ADS)

Pérez, José; Repasi, Endre

2018-04-01

A modeling scheme for active imaging through atmospheric turbulence is presented. The model consists of two parts: In the first part, the illumination laser beam is propagated to a target that is described by its reflectance properties, using the well-known split-step Fourier method for wave propagation. In the second part, the reflected intensity distribution imaged on a camera is computed using an empirical model developed for passive imaging through atmospheric turbulence. The split-step Fourier method requires carefully chosen simulation parameters. These simulation requirements together with the need to produce dynamic scenes with a large number of frames led us to implement the model on GPU. Validation of this implementation is shown for two different metrics. This model is well suited for Gated-Viewing applications. Examples of imaging simulation results are presented here.

A Compact 5.5 GHz Band-Rejected UWB Antenna Using Complementary Split Ring Resonators

PubMed Central

Islam, M. M.; Faruque, M. R. I.; Islam, M. T.

2014-01-01

A band-removal property employing microwave frequencies using complementary split ring resonators (CSRRs) is applied to design a compact UWB antenna wishing for the rejection of some frequency band, which is meanwhile exercised by the existing wireless applications. The reported antenna comprises optimization of a circular radiating patch, in which slotted complementary SRRs are implanted. It is printed on low dielectric FR4 substrate material fed by a partial ground plane and a microstrip line. Validated results exhibit that the reported antenna shows a wide bandwidth covering from 3.45 to more than 12 GHz, with a compact dimension of 22 × 26 mm2, and VSWR < 2, observing band elimination of 5.5 GHz WLAN band. PMID:24971379

Comparative Study on the Different Testing Techniques in Tree Classification for Detecting the Learning Motivation

NASA Astrophysics Data System (ADS)

Juliane, C.; Arman, A. A.; Sastramihardja, H. S.; Supriana, I.

2017-03-01

Having motivation to learn is a successful requirement in a learning process, and needs to be maintained properly. This study aims to measure learning motivation, especially in the process of electronic learning (e-learning). Here, data mining approach was chosen as a research method. For the testing process, the accuracy comparative study on the different testing techniques was conducted, involving Cross Validation and Percentage Split. The best accuracy was generated by J48 algorithm with a percentage split technique reaching at 92.19 %. This study provided an overview on how to detect the presence of learning motivation in the context of e-learning. It is expected to be good contribution for education, and to warn the teachers for whom they have to provide motivation.

Development of automated system based on neural network algorithm for detecting defects on molds installed on casting machines

NASA Astrophysics Data System (ADS)

Bazhin, V. Yu; Danilov, I. V.; Petrov, P. A.

2018-05-01

During the casting of light alloys and ligatures based on aluminum and magnesium, problems of the qualitative distribution of the metal and its crystallization in the mold arise. To monitor the defects of molds on the casting conveyor, a camera with a resolution of 780 x 580 pixels and a shooting rate of 75 frames per second was selected. Images of molds from casting machines were used as input data for neural network algorithm. On the preparation of a digital database and its analytical evaluation stage, the architecture of the convolutional neural network was chosen for the algorithm. The information flow from the local controller is transferred to the OPC server and then to the SCADA system of foundry. After the training, accuracy of neural network defect recognition was about 95.1% on a validation split. After the training, weight coefficients of the neural network were used on testing split and algorithm had identical accuracy with validation images. The proposed technical solutions make it possible to increase the efficiency of the automated process control system in the foundry by expanding the digital database.

Development of a new multidimensional individual and interpersonal resilience measure for older adults.

PubMed

Martin, A'verria Sirkin; Distelberg, Brian; Palmer, Barton W; Jeste, Dilip V

2015-01-01

Develop an empirically grounded measure that can be used to assess family and individual resilience in a population of older adults (aged 50-99). Cross-sectional, self-report data from 1006 older adults were analyzed in two steps. The total sample was split into two subsamples and the first step identified the underlying latent structure through principal component exploratory factor analysis (EFA). The second step utilized the second half of the sample to validate the derived latent structure through confirmatory factor analysis (CFA). EFA produced an eight-factor structure that appeared clinically relevant for measuring the multidimensional nature of resilience. Factors included self-efficacy, access to social support network, optimism, perceived economic and social resources, spirituality and religiosity, relational accord, emotional expression and communication, and emotional regulation. CFA confirmed the eight-factor structure previously achieved with covariance between each of the factors. Based on these analyses we developed the multidimensional individual and interpersonal resilience measure, a broad assessment of resilience for older adults. This study highlights the multidimensional nature of resilience and introduces an individual and interpersonal resilience measure developed for older adults which is grounded in the individual and family resilience literature.

Computer design of microfluidic mixers for protein/RNA folding studies.

PubMed

Inguva, Venkatesh; Kathuria, Sagar V; Bilsel, Osman; Perot, Blair James

2018-01-01

Kinetic studies of biological macromolecules increasingly use microfluidic mixers to initiate and monitor reaction progress. A motivation for using microfluidic mixers is to reduce sample consumption and decrease mixing time to microseconds. Some applications, such as small-angle x-ray scattering, also require large (>10 micron) sampling areas to ensure high signal-to-noise ratios and to minimize parasitic scattering. Chaotic to marginally turbulent mixers are well suited for these applications because this class of mixers provides a good middle ground between existing laminar and turbulent mixers. In this study, we model various chaotic to marginally turbulent mixing concepts such as flow turning, flow splitting, and vortex generation using computational fluid dynamics for optimization of mixing efficiency and observation volume. Design iterations show flow turning to be the best candidate for chaotic/marginally turbulent mixing. A qualitative experimental test is performed on the finalized design with mixing of 10 M urea and water to validate the flow turning unsteady mixing concept as a viable option for RNA and protein folding studies. A comparison of direct numerical simulations (DNS) and turbulence models suggests that the applicability of turbulence models to these flow regimes may be limited.

Food Source Prediction of Shiga Toxin-Producing Escherichia coli Outbreaks Using Demographic and Outbreak Characteristics, United States, 1998-2014.

PubMed

White, Alice; Cronquist, Alicia; Bedrick, Edward J; Scallan, Elaine

2016-10-01

Foodborne illness is a continuing public health problem in the United States. Although outbreak-associated illnesses represent a fraction of all foodborne illnesses, foodborne outbreak investigations provide critical information on the pathogens, foods, and food-pathogen pairs causing illness. Therefore, identification of a food source in an outbreak investigation is key to impacting food safety. The objective of this study was to systematically identify outbreak-associated case demographic and outbreak characteristics that are predictive of food sources using Shiga toxin-producing Escherichia coli (STEC) outbreaks reported to Centers for Disease Control and Prevention (CDC) from 1998 to 2014 with a single ingredient identified. Differences between STEC food sources by all candidate predictors were assessed univariately. Multinomial logistic regression was used to build a prediction model, which was internally validated using a split-sample approach. There were 206 single-ingredient STEC outbreaks reported to CDC, including 125 (61%) beef outbreaks, 30 (14%) dairy outbreaks, and 51 (25%) vegetable outbreaks. The model differentiated food sources, with an overall sensitivity of 80% in the derivation set and 61% in the validation set. This study demonstrates the feasibility for a tool for public health professionals to rule out food sources during hypothesis generation in foodborne outbreak investigation and to improve efficiency while complementing existing methods.

Rasch analysis of the Rosenberg Self-Esteem Scale with African Americans.

PubMed

Chao, Ruth Chu-Lien; Vidacovich, Courtney; Green, Kathy E

2017-03-01

Effectively diagnosing African Americans' self-esteem has posed an unresolved challenge. To address this assessment issue, we conducted exploratory factor analysis and Rasch analysis to assess the psychometric characteristics of the Rosenberg Self-Esteem Scale (RSES, Rosenberg, 1965) for African American college students. The dimensional structure of the RSES was first identified with the first subsample (i.e., calibration subsample) and then held up under cross-validation with a second subsample (i.e., validation subsample). Exploratory factor analysis and Rasch analysis both supported unidimensionality of the measure, with that finding replicated for a random split of the sample. Response scale use was generally appropriate, items were endorsed at a high level reflecting high levels of self-esteem, and person separation and reliability of person separation were adequate, and reflected results similar to those found in prior research. However, as some categories were infrequently used, we also collapsed scale points and found a slight improvement in scale and item indices. No differential item functioning was found by sex or having received professional assistance versus not; there were no mean score differences by age group, marital status, or year in college. Two items were seen as problematic. Implications for theory and research on multicultural mental health are discussed. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Individual Patient Diagnosis of AD and FTD via High-Dimensional Pattern Classification of MRI

PubMed Central

Davatzikos, C.; Resnick, S. M.; Wu, X.; Parmpi, P.; Clark, C. M.

2008-01-01

The purpose of this study is to determine the diagnostic accuracy of MRI-based high-dimensional pattern classification in differentiating between patients with Alzheimer’s Disease (AD), Frontotemporal Dementia (FTD), and healthy controls, on an individual patient basis. MRI scans of 37 patients with AD and 37 age-matched cognitively normal elderly individuals, as well as 12 patients with FTD and 12 age-matched cognitively normal elderly individuals, were analyzed using voxel-based analysis and high-dimensional pattern classification. Diagnostic sensitivity and specificity of spatial patterns of regional brain atrophy found to be characteristic of AD and FTD were determined via cross-validation and via split-sample methods. Complex spatial patterns of relatively reduced brain volumes were identified, including temporal, orbitofrontal, parietal and cingulate regions, which were predominantly characteristic of either AD or FTD. These patterns provided 100% diagnostic accuracy, when used to separate AD or FTD from healthy controls. The ability to correctly distinguish AD from FTD averaged 84.3%. All estimates of diagnostic accuracy were determined via cross-validation. In conclusion, AD- and FTD-specific patterns of brain atrophy can be detected with high accuracy using high-dimensional pattern classification of MRI scans obtained in a typical clinical setting. PMID:18474436

Combining Monte Carlo methods with coherent wave optics for the simulation of phase-sensitive X-ray imaging

PubMed Central

Peter, Silvia; Modregger, Peter; Fix, Michael K.; Volken, Werner; Frei, Daniel; Manser, Peter; Stampanoni, Marco

2014-01-01

Phase-sensitive X-ray imaging shows a high sensitivity towards electron density variations, making it well suited for imaging of soft tissue matter. However, there are still open questions about the details of the image formation process. Here, a framework for numerical simulations of phase-sensitive X-ray imaging is presented, which takes both particle- and wave-like properties of X-rays into consideration. A split approach is presented where we combine a Monte Carlo method (MC) based sample part with a wave optics simulation based propagation part, leading to a framework that takes both particle- and wave-like properties into account. The framework can be adapted to different phase-sensitive imaging methods and has been validated through comparisons with experiments for grating interferometry and propagation-based imaging. The validation of the framework shows that the combination of wave optics and MC has been successfully implemented and yields good agreement between measurements and simulations. This demonstrates that the physical processes relevant for developing a deeper understanding of scattering in the context of phase-sensitive imaging are modelled in a sufficiently accurate manner. The framework can be used for the simulation of phase-sensitive X-ray imaging, for instance for the simulation of grating interferometry or propagation-based imaging. PMID:24763652

Technical note: Validation of a handheld meter for measuring β-hydroxybutyrate concentrations in plasma and serum from dairy cows.

PubMed

Pineda, A; Cardoso, F C

2015-12-01

The use of handheld meters for cow-side tests for β-hydroxybutyrate (BHB) concentrations in whole blood has become common. The aim of this study was to compare serum BHB (sBHB) and plasma BHB (pBHB) concentrations analyzed using either a "gold standard" enzymatic laboratory method (LM; Randox Laboratories Ltd., Antrim, UK; cat. no. RB1007) or a handheld meter (PX; Precision Xtra, Abbott Diabetes Care Inc., Alameda, CA). Results from 374 (187 serum and 187 plasma) samples taken from Holstein cows from 11 d before (52 samples) to 5 d after parturition (137 samples) were used for the analysis. Statistical analysis was performed using the MIXED, REG, and LOGISTIC procedures of SAS (v9.4; SAS Institute Inc., Cary, NC). A linear mixed model with repeated measures was fitted for LM and PX. Regression and correlation analyses were completed to estimate the relationship and agreement between the 2 methods. Lin's concordance correlation coefficient (CCC) and Bland-Altman plots were used to evaluate agreement between LM and PX. Cross-validation by randomly splitting the data in model-building and validation sets was performed to estimate and validate the equation that predicted the LM results using PX. Receiver operating characteristic (ROC) curves were used to estimate the sensitivity (Se) and specificity (Sp) of PX at different threshold levels. The CCC was 0.74 for pBHB and 0.68 for sBHB. The 95% confidence interval of agreement of the Bland-Altman plot encompassed 96% of the difference between LM and PX for pBHB and 95% for sBHB. The mean difference for pBHB was -0.50±0.25mmol, and that for sBHB was -0.63±0.41mmol. The highest Se and Sp for PX were achieved when the threshold for ketosis was set to 1.8mmol/L for pBHB and 2.1mmol/L for sBHB. The area under the ROC curve was 0.97 for pBHB and 0.96 for sBHB. The negative bias shown by the Bland-Altman plots suggested that PX yielded higher pBHB and sBHB concentrations than the LM. However, the excellent test characteristics and area under the ROC curve close to 1 indicated that PX at the adjusted thresholds was able to accurately classify between samples <1.2mmol/L and those ≥1.2mmol/L based on the gold standard test. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Replicating cluster subtypes for the prevention of adolescent smoking and alcohol use.

PubMed

Babbin, Steven F; Velicer, Wayne F; Paiva, Andrea L; Brick, Leslie Ann D; Redding, Colleen A

2015-01-01

Substance abuse interventions tailored to the individual level have produced effective outcomes for a wide variety of behaviors. One approach to enhancing tailoring involves using cluster analysis to identify prevention subtypes that represent different attitudes about substance use. This study applied this approach to better understand tailored interventions for smoking and alcohol prevention. Analyses were performed on a sample of sixth graders from 20 New England middle schools involved in a 36-month tailored intervention study. Most adolescents reported being in the Acquisition Precontemplation (aPC) stage at baseline: not smoking or not drinking and not planning to start in the next six months. For smoking (N=4059) and alcohol (N=3973), each sample was randomly split into five subsamples. Cluster analysis was performed within each subsample based on three variables: Pros and Cons (from Decisional Balance Scales), and Situational Temptations. Across all subsamples for both smoking and alcohol, the following four clusters were identified: (1) Most Protected (MP; low Pros, high Cons, low Temptations); (2) Ambivalent (AM; high Pros, average Cons and Temptations); (3) Risk Denial (RD; average Pros, low Cons, average Temptations); and (4) High Risk (HR; high Pros, low Cons, and very high Temptations). Finding the same four clusters within aPC for both smoking and alcohol, replicating the results across the five subsamples, and demonstrating hypothesized relations among the clusters with additional external validity analyses provide strong evidence of the robustness of these results. These clusters demonstrate evidence of validity and can provide a basis for tailoring interventions. Copyright © 2014. Published by Elsevier Ltd.

Replicating cluster subtypes for the prevention of adolescent smoking and alcohol use

PubMed Central

Babbin, Steven F.; Velicer, Wayne F.; Paiva, Andrea L.; Brick, Leslie Ann D.; Redding, Colleen A.

2015-01-01

Introduction Substance abuse interventions tailored to the individual level have produced effective outcomes for a wide variety of behaviors. One approach to enhancing tailoring involves using cluster analysis to identify prevention subtypes that represent different attitudes about substance use. This study applied this approach to better understand tailored interventions for smoking and alcohol prevention. Methods Analyses were performed on a sample of sixth graders from 20 New England middle schools involved in a 36-month tailored intervention study. Most adolescents reported being in the Acquisition Precontemplation (aPC) stage at baseline: not smoking or not drinking and not planning to start in the next six months. For smoking (N= 4059) and alcohol (N= 3973), each sample was randomly split into five subsamples. Cluster analysis was performed within each subsample based on three variables: Pros and Cons (from Decisional Balance Scales), and Situational Temptations. Results Across all subsamples for both smoking and alcohol, the following four clusters were identified: (1) Most Protected (MP; low Pros, high Cons, low Temptations); (2) Ambivalent (AM; high Pros, average Cons and Temptations); (3) Risk Denial (RD; average Pros, low Cons, average Temptations); and (4) High Risk (HR; high Pros, low Cons, and very high Temptations). Conclusions Finding the same four clusters within aPC for both smoking and alcohol, replicating the results across the five subsamples, and demonstrating hypothesized relations among the clusters with additional external validity analyses provide strong evidence of the robustness of these results. These clusters demonstrate evidence of validity and can provide a basis for tailoring interventions. PMID:25222849

Preliminary development of a revised version of the School Climate Measure.

PubMed

Zullig, Keith J; Collins, Rani; Ghani, Nadia; Hunter, Amy A; Patton, Jon M; Huebner, E Scott; Zhang, Jianjun

2015-09-01

The School Climate Measure (SCM) was developed and preliminarily validated in 2010 and extended upon in 2013 in response to a dearth of psychometrically sound school climate instruments. This study sought to further validate the SCM on a large diverse sample of Arizona public school adolescents (N = 1,643) with two new domains. The eight original SCM domains (Positive Student-Teacher Relationships, School Connectedness, Academic Support, Order and Discipline, Physical Environment, Social Environment, Perceived Exclusion, and Academic Satisfaction) and two newly developed domains (Parental Involvement and Opportunities for Student Engagement) were subjected to psychometric analysis. The sample was randomly split into exploratory and confirmatory halves and subjected to factor analytic and structural equation modeling techniques. Factor analysis confirmed a 10-factor solution (loadings with absolute values > .40). Item factor loadings ranged from .47 to .95. Coefficient alphas ranged from .70 to .92. Fit statistics indicated a good fitting model (χ2 = 1452.67 [df = 734, p < .01], CFI = .94, TLI = .93, RMSEA = .039). This process eliminated some original SCM items, but the overall SCM increased only from 39 to 42 items with the newly developed domains. This investigation adds to the existing evidence for the SCM and offers support for a more comprehensive version of the SCM. The addition of the Parental Involvement and Opportunities for Student Engagement domains should further enhance the usefulness of the SCM. The SCM can facilitate data-driven decisions and may be incorporated into evidenced-based processes designed to improve important student learning and well-being outcomes. (c) 2015 APA, all rights reserved.

"DNA Origami Traffic Lights" with a Split Aptamer Sensor for a Bicolor Fluorescence Readout.

PubMed

Walter, Heidi-Kristin; Bauer, Jens; Steinmeyer, Jeannine; Kuzuya, Akinori; Niemeyer, Christof M; Wagenknecht, Hans-Achim

2017-04-12

A split aptamer for adenosine triphosphate (ATP) was embedded as a recognition unit into two levers of a nanomechanical DNA origami construct by extension and modification of selected staple strands. An additional optical module in the stem of the split aptamer comprised two different cyanine-styryl dyes that underwent an energy transfer from green (donor) to red (acceptor) emission if two ATP molecules were bound as target molecule to the recognition module and thereby brought the dyes in close proximity. As a result, the ATP as a target triggered the DNA origami shape transition and yielded a fluorescence color change from green to red as readout. Conventional atomic force microscopy (AFM) images confirmed the topology change from the open form of the DNA origami in the absence of ATP into the closed form in the presence of the target molecule. The obtained closed/open ratios in the absence and presence of target molecules tracked well with the fluorescence color ratios and thereby validated the bicolor fluorescence readout. The correct positioning of the split aptamer as the functional unit farthest away from the fulcrum of the DNA origami was crucial for the aptasensing by fluorescence readout. The fluorescence color change allowed additionally to follow the topology change of the DNA origami aptasensor in real time in solution. The concepts of fluorescence energy transfer for bicolor readout in a split aptamer in solution, and AFM on surfaces, were successfully combined in a single DNA origami construct to obtain a bimodal readout. These results are important for future custom DNA devices for chemical-biological and bioanalytical purposes because they are not only working as simple aptamers but are also visible by AFM on the single-molecule level.

Analysis of drug content and weight uniformity for half-tablets of 6 commonly split medications.

PubMed

Hill, Shaynan W; Varker, Andrew S; Karlage, Kelly; Myrdal, Paul B

2009-04-01

Cost savings can be achieved with the practice of tablet splitting. Previous research has shown weight nonuniformity within tablet halves. However, limited research to date has found that the potential dose inaccuracy resulting from splitting tablets does not significantly affect clinical outcomes. To determine the drug content and weight in split half-tablets of 6 commonly split medications using drug assay analysis. This study was performed by 2 fourth-year pharmacy students using 30 randomly selected tablets of each of the following 6 medications: warfarin sodium 5 milligrams (mg), simvastatin 80 mg, metoprolol succinate 200 mg, metoprolol tartrate 25 mg, citalopram 40 mg, and lisinopril 40 mg. A randomly selected half of the tablets were split by a single pharmacy student using a tablet cutter, and the remaining tablets were kept whole. Drug content was analyzed for 15 whole tablets and 30 half-tablets for each of the 6 drugs using high performance liquid chromatography, an analytical tool used to identify and quantify substances in solution. Drug content uniformity was assessed by comparing drug content within half-tablets with one-half of the drug content mean found for all whole tablets in the sample. Weight uniformity was assessed by comparing half-tablet weights, as determined by a Mettler analytical balance, with one-half of the mean weight for whole tablets in the sample. The percentages by which each whole tablet's or half-tablet's drug content and weight differed from sample mean values were compared with proxy United States Pharmacopeia (USP) specification ranges for drug content (95%-105% for warfarin sodium and 90%-110% for the other 5 drugs). Additionally, these outcomes were compared for nonscored versus scored tablets. The percent relative standard deviation (%RSD, ratio of the standard deviation to the mean), a commonly used measure of the repeatability and precision of assays used to analyze drug content, was also calculated in order to determine whether the drugs met proxy USP specification for %RSD (less than 6% for all drugs studied). A total of 43 of 180 half-tablets (23.9%) differed from sample mean values by a percentage that fell outside of proxy USP specification for drug content; warfarin sodium (11 of 30 half-tablets, 36.7%), simvastatin (3 of 30 half-tablets, 10.0%) metoprolol succinate (10 of 30 half-tablets, 33.3%), metoprolol tartrate (4 of 30 half-tablets, 13.3%), citalopram (5 of 30 half-tablets, 16.7%), and lisinopril (10 of 30 half-tablets, 33.3%). Half-tablets outside of proxy USP specification for weight included warfarin sodium (10 of 30 half-tablets, 33.3%), metoprolol succinate (6 of 30 half-tablets, 20%), and lisinopril (7 of 30 half-tablets, 23.3%). The %RSDs for drug content and weight fell outside of the proxy USP specification for %RSD for metoprolol succinate (drug content = 8.98%, weight = 7.70%) and lisinopril (drug content = 10.41%, weight = 8.13%). Mean percent weight loss after splitting was less than 1% for all drugs except lisinopril, which had an average weight loss of 1.25%. The total numbers of scored (nonscored) tablet halves that fell outside of proxy USP specification were 20 (23) for drug content and 10 (13) for weight. When measuring drug content, the numbers of out-of-range half-tablets for scored (nonscored) drugs were 36 (44) at 95%-105%, 9 (23) at 90%-110%, 0 (10) at 85%-115%, and 0 (1) at 75%-125%. When measuring weight, the numbers of out-of-range half-tablets for scored (nonscored) drugs were 28 (38) at 95%-105%, 0 (14) at 90%-110%, 0 (3) at 85%-115%, and 0 (0) at 75%-125%. Dose variation exceeded a proxy USP specification for more than one-third of sampled half-tablets of warfarin sodium, metoprolol succinate, and lisinopril and appeared to be greater for nonscored tablets as compared with scored tablets. Drug content variation in half-tablets appeared to be attributable primarily to weight variation occurring when tablets powder or fragment during the splitting process. Therefore, equal daily doses will be determined by the ability of patients to split tablets perfectly in half.

Characterization and validation of a split belt treadmill for measuring hindlimb ground-reaction forces in able-bodied and spinalized felines

PubMed Central

Dimiskovski, Marko; Scheinfield, Richard; Higgin, Dwight; Krupka, Alexander; Lemay, Michel A.

2017-01-01

BACKGROUND The measurement of ground reaction forces (GRFs) in animals trained to locomote on a treadmill after spinal cord injury (SCI) could prove valuable for evaluating training outcomes; however, quantitative measures of the GRFs in spinal felines are limited. NEW METHOD A split belt treadmill was designed and constructed to measure the GRFs of feline hindlimbs during stepping. The treadmill consists of two independent treadmill assemblies, each mounted on a force plate. The design allows measurements of the vertical (Fz), fore-aft (Fy) and mediolateral (Fx) ground-reaction forces for both hindlimbs while the forelimbs are resting on a platform. RESULTS Static and dynamic noise tests revealed little to no noise at frequencies below 6 Hz. Validation of the force plate measurements with a hand-held force sensor force showed good agreement between the two force readings. Peak normalized (to body mass) vertical GRFs for intact cats were 4.89±0.85N/Kg for the left hindlimb and 4.79±0.97N/Kg for the right. In comparison, trained spinalized cats peak normalized vertical GRFs were 2.20±0.94N/Kg for the left hindlimb and 2.85±0.99N/Kg for the right. COMPARISON WITH OTHER EXISTING METHODS Previous methods of measuring GRFs used stationary single force plates or treadmill mounted to single force plate. Using independent treadmills for each hindlimb allows measurement of the individual hindlimb’s GRFs in spinalized cats following body-weight supported treadmill training. CONCLUSIONS The split belt force treadmill enables the simultaneous recording of ground-reaction forces for both hindlimbs in cats prior to spinalization, and following spinalization and body-weight-supported treadmill training (BWST). PMID:28069392

Psychometric properties of a German organizational justice questionnaire (G-OJQ) and its association with self-rated health: findings from the Mannheim Industrial Cohort Studies (MICS).

PubMed

Herr, Raphael M; Li, Jian; Bosch, Jos A; Schmidt, Burkhard; DeJoy, David M; Fischer, Joachim E; Loerbroks, Adrian

2014-01-01

The objective of the present study was to validate a German 11-item organizational justice questionnaire (G-OJQ) that consists of two subscales, referred to as "procedural justice" (PJ) and "interactional justice" (IJ) adapted from Moorman's organizational justice (OJ) questionnaire. A second objective was to determine associations of the G-OJQ with self-rated health. This study used cross-sectional data from an occupational cohort of 1518 factory workers from Germany (87.7 % male; mean age = 38.8 with SD = 11.9). After splitting the sample in two random subsamples, we assessed structural validity by exploratory factor analyses in one subsample and by confirmatory factor analysis in the other subsample. Internal validity was assessed by Cronbach's α. Associations with self-reported poor health were estimated by logistic regression. The full scale and its subscales yielded Cronbach's α's of ≥0.9, and item-total correlations were ≥0.5. Factor analyses confirmed the expected 2-factor structure, labeled "interactional justice" (IJ, 4 items, λ 0.43-0.94) and "procedural justice" (PJ, 7 items, λ 0.46-0.83), respectively, and showed an acceptable fit to the data (χ (2) = 61; p = .001; CFI = 0.995; RMSEA = 0.037). The OJ total score as well as subscale scores in the lowest quartile, when compared to the highest quartile, was associated with an ≥2.3 increased odds of reporting poor health. The G-OJQ seems to be a valid and useful tool for observational and intervention studies in occupational settings. Future studies may additionally explore longitudinal associations and test the generalizability of the present findings to other populations and health outcomes.

Validating the Use of Deep Learning Neural Networks for Correction of Large Hydrometric Datasets

NASA Astrophysics Data System (ADS)

Frazier, N.; Ogden, F. L.; Regina, J. A.; Cheng, Y.

2017-12-01

Collection and validation of Earth systems data can be time consuming and labor intensive. In particular, high resolution hydrometric data, including rainfall and streamflow measurements, are difficult to obtain due to a multitude of complicating factors. Measurement equipment is subject to clogs, environmental disturbances, and sensor drift. Manual intervention is typically required to identify, correct, and validate these data. Weirs can become clogged and the pressure transducer may float or drift over time. We typically employ a graphical tool called Time Series Editor to manually remove clogs and sensor drift from the data. However, this process is highly subjective and requires hydrological expertise. Two different people may produce two different data sets. To use this data for scientific discovery and model validation, a more consistent method is needed to processes this field data. Deep learning neural networks have proved to be excellent mechanisms for recognizing patterns in data. We explore the use of Recurrent Neural Networks (RNN) to capture the patterns in the data over time using various gating mechanisms (LSTM and GRU), network architectures, and hyper-parameters to build an automated data correction model. We also explore the required amount of manually corrected training data required to train the network for reasonable accuracy. The benefits of this approach are that the time to process a data set is significantly reduced, and the results are 100% reproducible after training is complete. Additionally, we train the RNN and calibrate a physically-based hydrological model against the same portion of data. Both the RNN and the model are applied to the remaining data using a split-sample methodology. Performance of the machine learning is evaluated for plausibility by comparing with the output of the hydrological model, and this analysis identifies potential periods where additional investigation is warranted.

[Reliability and validity of Professional Quality of Life Scale among government staff in earthquake - stricken areas in China].

PubMed

Dang, Weimin; Cheng, Wenhong; Ma, Hong; Lin, Jin; Wu, Baoming; Ma, Ning; Wang, Rongke; Xu, Junting; Zhou, Tianhang; Yu, Xin

2015-06-01

To evaluate the reliability and validity of Professional Quality of Life Scale (ProQOL-30, 4th version, 30 items) among government staff in the Wenchuan earthquake-stricken areas A total of 1,175 members of government staff in the Wenchuan earthquake-stricken areas were selected by convenience sampling and required to complete the ProQOL and Self-Reporting Questionnair (SRQ). The reliability and validity of the scale was evaluated by correlation analysis, t-test, and confirmatory factor analysis. Item-total correlation coefficients of the three subscales were 0.590 - 0.752, 0.389 - 0.603, and 0.340 - 0.647, respectively (P<0.05), and the average coefficients were 0.672, 0.482, and 0.555 respectively (P<0.05). The Cronbach's α coefficients of the three subscales were 0.864, 0.569, and 0.742 respectively, and the split-half reliabilities were 0.829, 0.490, and 0.677, respectively. P value was 0.88 in thE chi-square test of confirmatory factor analysis model. Goodness-of-fit indices of ProQOL-30 included GFI=0.895 NFI=0.856, CFI=0.895, RMSEA=0.063, and AGFI=0.912. For the ProQOL-28 as an optimized version o ProQOL-30, the Cronbach's a coefficients for burnout and trauma/compassion fatigue increased to 0.616 and 0.757, respectively. P value was 0.91 in the chi-square test of confirmatory factor analysis model test. Goodness-of-fit indices of ProQOL-28 were GFI =0.913, AGFI =0.924, NFI =0.900, CFI =0.913, and RMSEA =0.031 CONCLUSION: ProQOL-28 has good reliability and validity among government staff in the earthquake-stricker areas in China.

PROGNOSTIC SIGNIFICANCE OF CLINICAL, HISTOPATHOLOGICAL, AND MOLECULAR CHARACTERISTICS OF MEDULLOBLASTOMAS IN THE PROSPECTIVE HIT2000 MULTICENTER CLINICAL TRIAL COHORT

PubMed Central

Pietsch, Torsten; Schmidt, Rene; Remke, Marc; Korshunov, Andrey; Hovestadt, Volker; Jones, David TW; Felsberg, Jörg; Kaulich, Kerstin; Goschzik, Tobias; Kool, Marcel; Northcott, Paul A.; von Hoff, Katja; von Bueren, André O.; Friedrich, Carsten; Skladny, Heyko; Fleischhack, Gudrun; Taylor, Michael D.; Cremer, Friedrich; Lichter, Peter; Faldum, Andreas; Reifenberger, Guido; Rutkowski, Stefan; Pfister, Stefan M.

2014-01-01

BACKGROUND: This study aimed to prospectively evaluate clinical, histopathological and molecular variables for outcome prediction in medulloblastoma patients. METHODS: Patients from the HIT2000 cooperative clinical trial were prospectively enrolled based on the availability of sufficient tumor material and complete clinical information. This revealed a cohort of 184 patients (median age 7.6 years), which was randomly split at a 2:1 ratio into a training (n = 127), and a validation (n = 57) dataset. All samples were subjected to thorough histopathological investigation, CTNNB1 mutation analysis, quantitative PCR, MLPA and FISH analyses for cytogenetic variables, and methylome analysis. RESULTS: By univariable analysis, clinical factors (M-stage), histopathological variables (large cell component, endothelial proliferation, synaptophysin pattern), and molecular features (chromosome 6q status, MYC amplification, TOP2A copy-number, subgrouping) were found to be prognostic. Molecular consensus subgrouping (WNT, SHH, Group 3, Group 4) was validated as an independent feature to stratify patients into different risk groups. When comparing methods for the identification of WNT-driven medulloblastoma, this study identified CTNNB1 sequencing and methylation profiling to most reliably identify these patients. After removing patients with particularly favorable (CTNNB1 mutation, extensive nodularity) or unfavorable (MYC amplification) markers, a risk score for the remaining “intermediate molecular risk” population dependent on age, M-stage, pattern of synaptophysin expression, and MYCN copy-number status was identified and validated, with speckled synaptophysin expression indicating worse outcome. CONCLUSIONS: Methylation subgrouping and CTNNB1 mutation status represent robust tools for the risk-stratification of medulloblastoma. A simple clinico-pathological risk score for “intermediate molecular risk” patients was identified, which deserves further validation. SECONDARY CATEGORY: Pediatrics.

Validity and reliability of the Hawaii anaerobic run test.

PubMed

Kimura, Iris F; Stickley, Christopher D; Lentz, Melissa A; Wages, Jennifer J; Yanagi, Kazuhiko; Hetzler, Ronald K

2014-05-01

This study examined the reliability and validity of the Hawaii anaerobic run test (HART) by comparing anaerobic capacity measures obtained to those during the Wingate Anaerobic Test (WAnT). Ninety-six healthy physically active volunteers (age, 22.0 ± 2.8 years; height, 163.9 ± 9.5 cm; body mass, 70.6 ± 14.7 kg; body fat %, 19.29 ± 5.39%) participated in this study. Each participant performed 2 anaerobic capacity tests: the WAnT and the HART by random assignment on separate days. The reliability of the HART was calculated from 2 separate trials of the test and then determined through intraclass correlation coefficients (ICCs). Blood samples were collected, and lactate was analyzed both pretest and posttest for each of the 2 exercise modes. Heart rate and rate of perceived exertion were also measured pre- and post-exercise. Hawaii anaerobic run test peak and mean momentum were calculated as body mass times highest or average split velocity, respectively. Intraclass correlation coefficients between trials of the HART for peak and mean momentum were 0.98 and 0.99, respectively (SEM = 18.8 and 25.7, respectively). Validity of the HART was established through comparison of momentum on the HART with power on the WAnT. High correlations were found between peak power and peak momentum (r = 0.88), as well as mean power and mean momentum (r = 0.94). The HART was considered to be a reliable test of anaerobic power. The HART was also determined to be a valid test of anaerobic power when compared with the WAnT. When testing healthy college-aged individuals, the HART offers an easy and inexpensive alternative maximal effort anaerobic power test to other established tests.

The validity and psychometric properties of the Japanese version of the Compulsive Internet Use Scale (CIUS).

PubMed

Yong, Roseline Kim Fong; Inoue, Akiomi; Kawakami, Norito

2017-05-30

Prolonged Internet use is often associated with reduced social involvement and comorbid psychopathologies, including depression, anxiety, attention-deficit/hyperactivity disorder, and obsessive-compulsive disorder. Asian countries where Internet access is widely available have high reported levels of Internet addiction. As Internet use has changed drastically since concerns about Internet addiction were first raised, the results of recent studies may be inaccurate because the scales they employed to measure Internet addiction were formulated for different Internet usage from the present. It is thus necessary to develop more-up-to-date scales to assess problematic private use of the Internet. The Compulsive Internet Use Scale (CIUS) was translated into Japanese. An online sample whose ages and sexes reflected that of the national population of Internet users was recruited to test the scale's reliability and validity. Correlations between the scale and Internet-related parameters (such as time spent online, motivation for going online, and applications used) and psychosocial factors (such as psychological distress symptoms and loneliness) were examined. Psychometric properties were examined by the split-half method using both exploratory and confirmatory factor analysis. Model fits were compared across gender. CIUS was found to have a high reliability and good concurrent, correlation and construct validity. Both exploratory and confirmatory factors revealed that the one-factor solution yielded a satisfactory result across gender. However, the three-factor structural model in which compulsiveness was gauged by "excessive absorption", "difficulty in setting priorities", and "mood regulation" gave the best fit of the model for the general population as well as across gender. Compulsive Internet behavior in Japan can be assessed in terms of absorption, priorities, and mood. CIUS is a valid scale for screening compulsive Internet behavior in the general Japanese population regardless of age and gender.

Emergency Department Care in the Postpartum Period: California Births, 2009-2011.

PubMed

Batra, Priya; Fridman, Moshe; Leng, Mei; Gregory, Kimberly D

2017-11-01

To use population data to identify patient characteristics associated with a postpartum maternal emergency department visit within 90 days of discharge after birth. This retrospective cross-sectional study analyzed linked maternal discharge and emergency department data for all live California births from 2009 to 2011. The primary outcome was at least one emergency department visit within 90 days of hospital discharge after birth. Secondary outcomes included three or more visits within 90 days ("high utilization") and inpatient readmission. Independent variables included demographics (age, race or ethnicity, payer, income) and clinical characteristics (length of stay, antepartum complications, mode of delivery, and severe maternal morbidity at delivery). Multilevel logistic regression identified variables associated study outcomes; we validated the predictive model with a split-sample approach and receiver operating characteristic curve analysis. Of 1,071,232 deliveries included, 88,674 women (8.3%) visited the emergency department at least once in the 90 days after delivery discharge. Emergency department use was significantly associated with Medicaid insurance (adjusted odds ratio [OR] 2.15, 95% CI 2.08-2.21), age younger than 20 years (adjusted OR 2.08, 95% CI 1.98-2.19), severe maternal morbidity at delivery (adjusted OR 1.58, 95% CI 1.49-1.71), antepartum complications (adjusted OR 1.46, 95% CI 1.42-1.50), and cesarean delivery (adjusted OR 1.40, 95% CI 1.37-1.44). Approximately one fifth of visits occurred within 4 days of discharge, and more than half were within 3 weeks. High utilizers comprised 0.5% of the entire sample (5,171 women) and only 1.2% of women presenting for emergency department care were readmitted. Receiver operating curve model analysis using the validation sample supported predictive accuracy for postpartum emergency department use (area under the curve=0.95). One in 12 California women visited the emergency department in the first 90 days after postpartum discharge. Women at increased risk for postpartum emergency department use per our validated model (eg, low income, birth complications) may benefit from earlier scheduled postpartum visits.

Going above and beyond for implementation: the development and validity testing of the Implementation Citizenship Behavior Scale (ICBS).

PubMed

Ehrhart, Mark G; Aarons, Gregory A; Farahnak, Lauren R

2015-05-07

In line with recent research on the role of the inner context of organizations in implementation effectiveness, this study extends research on organizational citizenship behavior (OCB) to the domain of evidence-based practice (EBP) implementation. OCB encompasses those behaviors that go beyond what is required for a given job that contribute to greater organizational effectiveness. The goal of this study was to develop and test a measure of implementation citizenship behavior (ICB) or those behaviors that employees perform that go above and beyond what is required in order to support EBP implementation. The primary participants were 68 supervisors from ten mental health agencies throughout California. Items measuring ICB were developed based on past research on OCB and in consultation with experts on EBP implementation in mental health settings. Supervisors rated 357 of their subordinates on ICB and implementation success. In addition, 292 of the subordinates provided data on self-rated performance, attitudes towards EBPs, work experience, and full-time status. The supervisor sample was randomly split, with half used for exploratory factor analyses and the other half for confirmatory factor analyses. The entire sample of supervisors and subordinates was utilized for analyses assessing the reliability and construct validity of the measure. Exploratory factor analyses supported the proposed two-factor structure of the Implementation Citizenship Behavior Scale (ICBS): (1) Helping Others and (2) Keeping Informed. Confirmatory factor analyses with the other half of the sample supported the factor structure. Additional analyses supported the reliability and construct validity for the ICBS. The ICBS is a pragmatic brief measure (six items) that captures critical behaviors employees perform to go above and beyond the call of duty to support EBP implementation, including helping their fellow employees on implementation-related activities and keeping informed about issues related to EBP and implementation efforts. The ICBS can be used by researchers to better understand the outcomes of improved organizational support for implementation (i.e., implementation climate) and the proximal predictors of implementation effectiveness. The ICBS can also provide insight for organizations, practitioners, and managers by focusing on key employee behaviors that should increase the probability of implementation success.

Safety and immunogenicity of adjuvanted inactivated split-virion and whole-virion influenza A (H5N1) vaccines in children: a phase I-II randomized trial.

PubMed

Wu, Jiang; Liu, Shu-Zhen; Dong, Shan-Shan; Dong, Xiao-Ping; Zhang, Wu-Li; Lu, Min; Li, Chang-Gui; Zhou, Ji-Chen; Fang, Han-Hua; Liu, Yan; Liu, Li-Ying; Qiu, Yuan-Zheng; Gao, Qiang; Zhang, Xiao-Mei; Chen, Jiang-Ting; Zhong, Xiang; Yin, Wei-Dong; Feng, Zi-Jian

2010-08-31

Highly pathogenic avian influenza A virus H5N1 has the potential to cause a pandemic. Many prototype pandemic influenza A (H5N1) vaccines had been developed and well evaluated in adults in recent years. However, data in children are limited. Herein we evaluate the safety and immunogenicity of adjuvanted split-virion and whole-virion H5N1 vaccines in children. An open-labelled phase I trial was conducted in children aged 3-11 years to receive aluminum-adjuvated, split-virion H5N1 vaccine (5-30 microg) and in children aged 12-17 years to receive aluminum-adjuvated, whole-virion H5N1 vaccine (5-15 microg). Safety of the two formulations was assessed. Then a randomized phase II trial was conducted, in which 141 children aged 3-11 years received the split-virion vaccine (10 or 15 microg) and 280 children aged 12-17 years received the split-virion vaccine (10-30 microg) or the whole-virion vaccine (5 microg). Serum samples were collected for hemagglutination-inhibition (HI) assays. 5-15 microg adjuvated split-virion vaccines were well tolerated in children aged 3-11 years and 5-30 microg adjuvated split-virion vaccines and 5 microg adjuvated whole-virion vaccine were well tolerated in children aged 12-17 years. Most local and systemic reactions were mild or moderate. Before vaccination, all participants were immunologically naïve to H5N1 virus. Immune responses were induced after the first dose and significantly boosted after the second dose. In 3-11 years children, the 10 and 15 microg split-virion vaccine induced similar responses with 55% seroconversion and seroprotection (HI titer >or=1:40) rates. In 12-17 years children, the 30 microg split-virion vaccine induced the highest immune response with 71% seroconversion and seroprotection rates. The 5 microg whole-virion vaccine induced higher response than the 10 microg split-virion vaccine did. The aluminum-adjuvanted, split-virion prototype pandemic influenza A (H5N1) vaccine showed good safety and immunogenicity in children and 30 microg dose induced immune response complying with European Union licensure criteria. (c) 2010 Elsevier Ltd. All rights reserved.

Determination of twenty-nine elements in eight argonne premium coal samples by instrumental neutron activation analysis

USGS Publications Warehouse

Palmer, C.A.

1990-01-01

Twenty-nine elements have been determined in triplicate splits of the eight Argonne National Laboratory Premium Coal Samples by instrumental neutron activtaion analysis. Data for control samples NBS 1633 (fly ash) and NBS 1632b are also reported. The factors that could lead to errors in analysis for these samples, such as spectral overlaps, low sensitivity, and interfering nuclear reactions, are discussed.

Transfer Relations Between Landscape Functions - The Hydrological Point of View

NASA Astrophysics Data System (ADS)

Fohrer, N.; Lenhart, T.; Eckhardt, K.; Frede, H.-G.

EC market policies and regional subsidy programs have an enormous impact on local land use. This has far reaching consequences on various landscape functions. In the joint research project SFB299 at the Giessen University the effect of land use options on economic, ecological and hydrological landscape functions are under investigation. The continuous time step model SWAT-G (Eckhardt et al., 2000; Arnold et al., 1998) is employed to characterize the influence of land use patterns on hydrological processes. The model was calibrated and validated employing a split sample approach. For two mesoscale watersheds (Aar, 60 km2; Dietzhölze, 81 km2) located in the Lahn-Dill- Bergland, Germany, different land use scenarios were analyzed with regard to their hydrological impact. Additionally the effect of land use change was analyzed with an ecological and an agro-economic model. The impact of the stepwise changing land use was expressed as trade off relations between different landscape functions.

Description and Evaluation of a Measurement Technique for Assessment of Performing Gender

PubMed Central

Harris, Kathleen Mullan; Halpern, Carolyn Tucker

2016-01-01

The influence of masculinity and femininity on behaviors and outcomes has been extensively studied in social science research using various measurement strategies. In the present paper, we describe and evaluate a measurement technique that uses existing survey items to capture the extent to which an individual behaves similarly to their same-gender peers. We use data from the first four waves of The National Longitudinal Study of Adolescent to Adult Health (Add Health), a nationally representative sample of adolescents (age 12–18) in the United States who were re-interviewed at ages 13–19, 18–26, and 24–32. We estimate split-half reliability and provide evidence that supports the validity of this measurement technique. We demonstrate that the resulting measure does not perform as a trait measure and is associated with involvement in violent fights, a pattern consistent with theory and empirical findings. This measurement technique represents a novel approach for gender researchers with the potential for expanding our current knowledge base. PMID:28630528

Cognitive subtypes of dyslexia are characterized by distinct patterns of grey matter volume.

PubMed

Jednoróg, Katarzyna; Gawron, Natalia; Marchewka, Artur; Heim, Stefan; Grabowska, Anna

2014-09-01

The variety of different causal theories together with inconsistencies about the anatomical brain markers emphasize the heterogeneity of developmental dyslexia. Attempts were made to test on a behavioral level the existence of subtypes of dyslexia showing distinguishable cognitive deficits. Importantly, no research was directly devoted to the investigation of structural brain correlates of these subtypes. Here, for the first time, we applied voxel-based morphometry (VBM) to study grey matter volume (GMV) differences in a relatively large sample (n = 46) of dyslexic children split into three subtypes based on the cognitive deficits: phonological, rapid naming, magnocellular/dorsal, and auditory attention shifting. VBM revealed GMV clusters specific for each studied group including areas of left inferior frontal gyrus, cerebellum, right putamen, and bilateral parietal cortex. In addition, using discriminant analysis on these clusters 79% of cross-validated cases were correctly re-classified into four groups (controls vs. three subtypes). Current results indicate that dyslexia may result from distinct cognitive impairments characterized by distinguishable anatomical markers.

Linguistic Adaptation and Psychometric Properties of Tamil Version of General Oral Health Assessment Index-Tml.

PubMed

Appukuttan, D P; Vinayagavel, M; Balasundaram, A; Damodaran, L K; Shivaraman, P; Gunasshegaran, K

2015-01-01

Oral health has an impact on quality of life hence for research purpose validation of a Tamil version of General Oral Health Assessment Index would enable it to be used as a valuable tool among Tamil speaking population. In this study, we aimed to assess the psychometric properties of translated Tamil version of General Oral Health Assessment Index (GOHAI-Tml). Linguistic adaptation involved forward and backward blind translation process. Reliability was analyzed using test-retest, Cronbach alpha, and split half reliability. Inter-item and item-total correlation were evaluated using Spearman rank correlation. Convenience sampling was done, and 265 consecutive patients aged 20-70 years attending the outpatient department were recruited. Subjects were requested to fill a self-reporting questionnaire along with Tamil GOHAI version. Clinical examination was done on the same visit. Concurrent validity was measured by assessing the relationship between GOHAI scores and self-perceived oral health and general health status, satisfaction with oral health, need for dental treatment and esthetic satisfaction. Discriminant validity was evaluated by comparing the GOHAI scores with the objectively assessed clinical parameters. Exploratory factor analysis was done to examine the factor structure. Mean GOHAI-Tml was 52.7 (6.8, range 22-60, median 54). The mean number of negative impacts was 2 (2.4, range 0-11, median 1). The Spearman rank correlation for test-retest ranged from 0.8 to 0.9 (P < 0.001) for all the 12 items between visits. The Cronbach alpha for 265 samples was 0.8 suggesting good internal consistency and homogeneity between items. Item scale correlation ranged from 0.4 to 0.8 (P < 0.001). Concurrent and discriminant validity was established. Principal component analysis resulted in extraction of four factors which together accounted for 66.4% (7.9/12) variance. GOHAI-Tml has shown acceptable psychometric properties, so that it can be used as an efficient tool in identifying the impact of oral health on quality of life among the Tamil speaking population.

The Identification of Novel Potential Injury Mechanisms and Candidate Biomarkers in Renal Allograft Rejection by Quantitative Proteomics*

PubMed Central

Sigdel, Tara K.; Salomonis, Nathan; Nicora, Carrie D.; Ryu, Soyoung; He, Jintang; Dinh, Van; Orton, Daniel J.; Moore, Ronald J.; Hsieh, Szu-Chuan; Dai, Hong; Thien-Vu, Minh; Xiao, Wenzhong; Smith, Richard D.; Qian, Wei-Jun; Camp, David G.; Sarwal, Minnie M.

2014-01-01

Early transplant dysfunction and failure because of immunological and nonimmunological factors still presents a significant clinical problem for transplant recipients. A critical unmet need is the noninvasive detection and prediction of immune injury such that acute injury can be reversed by proactive immunosuppression titration. In this study, we used iTRAQ -based proteomic discovery and targeted ELISA validation to discover and validate candidate urine protein biomarkers from 262 renal allograft recipients with biopsy-confirmed allograft injury. Urine samples were randomly split into a training set of 108 patients and an independent validation set of 154 patients, which comprised the clinical biopsy-confirmed phenotypes of acute rejection (AR) (n = 74), stable graft (STA) (n = 74), chronic allograft injury (CAI) (n = 58), BK virus nephritis (BKVN) (n = 38), nephrotic syndrome (NS) (n = 8), and healthy, normal control (HC) (n = 10). A total of 389 proteins were measured that displayed differential abundances across urine specimens of the injury types (p < 0.05) with a significant finding that SUMO2 (small ubiquitin-related modifier 2) was identified as a “hub” protein for graft injury irrespective of causation. Sixty-nine urine proteins had differences in abundance (p < 0.01) in AR compared with stable graft, of which 12 proteins were up-regulated in AR with a mean fold increase of 2.8. Nine urine proteins were highly specific for AR because of their significant differences (p < 0.01; fold increase >1.5) from all other transplant categories (HLA class II protein HLA-DRB1, KRT14, HIST1H4B, FGG, ACTB, FGB, FGA, KRT7, DPP4). Increased levels of three of these proteins, fibrinogen beta (FGB; p = 0.04), fibrinogen gamma (FGG; p = 0.03), and HLA DRB1 (p = 0.003) were validated by ELISA in AR using an independent sample set. The fibrinogen proteins further segregated AR from BK virus nephritis (FGB p = 0.03, FGG p = 0.02), a finding that supports the utility of monitoring these urinary proteins for the specific and sensitive noninvasive diagnosis of acute renal allograft rejection. PMID:24335474

Nondestructive imaging of fiber structure in articular cartilage using optical polarization tractography

NASA Astrophysics Data System (ADS)

Yao, Xuan; Wang, Yuanbo; Ravanfar, Mohammadreza; Pfeiffer, Ferris M.; Duan, Dongsheng; Yao, Gang

2016-11-01

Collagen fiber orientation plays an important role in determining the structure and function of the articular cartilage. However, there is currently a lack of nondestructive means to image the fiber orientation from the cartilage surface. The purpose of this study is to investigate whether the newly developed optical polarization tractography (OPT) can image fiber structure in articular cartilage. OPT was applied to obtain the depth-dependent fiber orientation in fresh articular cartilage samples obtained from porcine phalanges. For comparison, we also obtained collagen fiber orientation in the superficial zone of the cartilage using the established split-line method. The direction of each split-line was quantified using image processing. The orientation measured in OPT agreed well with those obtained from the split-line method. The correlation analysis of a total of 112 split-lines showed a greater than 0.9 coefficient of determination (R2) between the split-line results and OPT measurements obtained between 40 and 108 μm in depth. In addition, the thickness of the superficial layer can also be assessed from the birefringence images obtained in OPT. These results support that OPT provides a nondestructive way to image the collagen fiber structure in articular cartilage. This technology may be valuable for both basic cartilage research and clinical orthopedic applications.

78 FR 23533 - Endangered and Threatened Wildlife and Plants; 90-Day Finding on a Petition To Delist the Wood Bison

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-19

... classification and our rationale for accepting wood bison as a valid subspecies below. Taxonomy is the theory and... groups of animals should be lumped together or split apart. Such is the case for wood bison. We recognize... separated by a great distance, led Boyd et al. (2010, p. 16 (American Bison Specialist Group)) to conclude...

Automation of cellular therapy product manufacturing: results of a split validation comparing CD34 selection of peripheral blood stem cell apheresis product with a semi-manual vs. an automatic procedure.

PubMed

Hümmer, Christiane; Poppe, Carolin; Bunos, Milica; Stock, Belinda; Wingenfeld, Eva; Huppert, Volker; Stuth, Juliane; Reck, Kristina; Essl, Mike; Seifried, Erhard; Bonig, Halvard

2016-03-16

Automation of cell therapy manufacturing promises higher productivity of cell factories, more economical use of highly-trained (and costly) manufacturing staff, facilitation of processes requiring manufacturing steps at inconvenient hours, improved consistency of processing steps and other benefits. One of the most broadly disseminated engineered cell therapy products is immunomagnetically selected CD34+ hematopoietic "stem" cells (HSCs). As the clinical GMP-compliant automat CliniMACS Prodigy is being programmed to perform ever more complex sequential manufacturing steps, we developed a CD34+ selection module for comparison with the standard semi-automatic CD34 "normal scale" selection process on CliniMACS Plus, applicable for 600 × 10(6) target cells out of 60 × 10(9) total cells. Three split-validation processings with healthy donor G-CSF-mobilized apheresis products were performed; feasibility, time consumption and product quality were assessed. All processes proceeded uneventfully. Prodigy runs took about 1 h longer than CliniMACS Plus runs, albeit with markedly less hands-on operator time and therefore also suitable for less experienced operators. Recovery of target cells was the same for both technologies. Although impurities, specifically T- and B-cells, were 5 ± 1.6-fold and 4 ± 0.4-fold higher in the Prodigy products (p = ns and p = 0.013 for T and B cell depletion, respectively), T cell contents per kg of a virtual recipient receiving 4 × 10(6) CD34+ cells/kg was below 10 × 10(3)/kg even in the worst Prodigy product and thus more than fivefold below the specification of CD34+ selected mismatched-donor stem cell products. The products' theoretical clinical usability is thus confirmed. This split validation exercise of a relatively short and simple process exemplifies the potential of automatic cell manufacturing. Automation will further gain in attractiveness when applied to more complex processes, requiring frequent interventions or handling at unfavourable working hours, such as re-targeting of T-cells.

Psychometric properties of the Farsi version of effort-reward imbalance questionnaire: a longitudinal study in employees of a synthetic fibre factory in Iran.

PubMed

Yadegarfar, Ghasem; Alinia, Tahereh; Hosseini, Reihane; Hassannejad, Razieh; Fayaz, Mahsa; Sanati, Javad; Sanati, Kave; Harandi, Jalal; Hajnoorozali, Vahid; Baghi, Mahmood-Reza; Mirzavand, Enayat; Majeed, Azeem

2013-02-01

To assess the reliability and validity of the Farsi version of the effort-reward imbalance questionnaire (F-ERIQ) and to examine the responsiveness of the tool to changes over time. A longitudinal study was carried out among 227 male employees of Iran Polyacryl Corporation. The F-ERIQ was developed through a forward-backward translation process that includes three scales of effort, reward and over-commitment (OC). Reliability and internal consistency of the F-ERIQ were assessed by split-half and Cronbach's alpha coefficients. Confirmatory factor analysis, convergent and discriminant validity were conducted to evaluate construct validity. Depressive mood was used as an indicator for exploring criterion validity. The variations in mean scores over time for scales were regarded as measures of the responsiveness to changes. Baseline split-half correlations for effort, reward and OC were 0.53, 0.85 and 0.65, respectively; Cronbach's alpha coefficients improved from 0.61 to 0.70 for effort, 0.85 to 0.88 for reward and 0.67 to 0.72 for OC. All of item-total correlations were higher than 0.23 and item-scales correlations were higher than 0.4. Although Values of Goodness of Fit Index and Adjusted GFI were higher than 0.9 and Root Mean Square Error of Approximation, Root Mean Square Residual and Standardized RMR were lower than 0.05, confirmatory factor analysis only confirmed the construct of the effort and OC. People with higher job stress were at higher risk of depressive mood (at least 3 times more). Overall, the mean score of effort, OC and ERI increase, and the figures decrease for reward among people who experience changes. These findings provide evidence that the F-ERIQ is a reliable and valid instrument for assessing psychosocial stress at work among Farsi-speaking male employees. We propose that F-ERIQ be further evaluated across a variety of jobs and industries.

Development of models for classification of action between heat-clearing herbs and blood-activating stasis-resolving herbs based on theory of traditional Chinese medicine.

PubMed

Chen, Zhao; Cao, Yanfeng; He, Shuaibing; Qiao, Yanjiang

2018-01-01

Action (" gongxiao " in Chinese) of traditional Chinese medicine (TCM) is the high recapitulation for therapeutic and health-preserving effects under the guidance of TCM theory. TCM-defined herbal properties (" yaoxing " in Chinese) had been used in this research. TCM herbal property (TCM-HP) is the high generalization and summary for actions, both of which come from long-term effective clinical practice in two thousands of years in China. However, the specific relationship between TCM-HP and action of TCM is complex and unclear from a scientific perspective. The research about this is conducive to expound the connotation of TCM-HP theory and is of important significance for the development of the TCM-HP theory. One hundred and thirty-three herbs including 88 heat-clearing herbs (HCHs) and 45 blood-activating stasis-resolving herbs (BAHRHs) were collected from reputable TCM literatures, and their corresponding TCM-HPs/actions information were collected from Chinese pharmacopoeia (2015 edition). The Kennard-Stone (K-S) algorithm was used to split 133 herbs into 100 calibration samples and 33 validation samples. Then, machine learning methods including supported vector machine (SVM), k-nearest neighbor (kNN) and deep learning methods including deep belief network (DBN), convolutional neutral network (CNN) were adopted to develop action classification models based on TCM-HP theory, respectively. In order to ensure robustness, these four classification methods were evaluated by using the method of tenfold cross validation and 20 external validation samples for prediction. As results, 72.7-100% of 33 validation samples including 17 HCHs and 16 BASRHs were correctly predicted by these four types of methods. Both of the DBN and CNN methods gave out the best results and their sensitivity, specificity, precision, accuracy were all 100.00%. Especially, the predicted results of external validation set showed that the performance of deep learning methods (DBN, CNN) were better than traditional machine learning methods (kNN, SVM) in terms of their sensitivity, specificity, precision, accuracy. Moreover, the distribution patterns of TCM-HPs of HCHs and BASRHs were also analyzed to detect the featured TCM-HPs of these two types of herbs. The result showed that the featured TCM-HPs of HCHs were cold, bitter, liver and stomach meridians entered, while those of BASRHs were warm, bitter and pungent, liver meridian entered. The performance on validation set and external validation set of deep learning methods (DBN, CNN) were better than machine learning models (kNN, SVM) in sensitivity, specificity, precision, accuracy when predicting the actions of heat-clearing and blood-activating stasis-resolving based on TCM-HP theory. The deep learning classification methods owned better generalization ability and accuracy when predicting the actions of heat-clearing and blood-activating stasis-resolving based on TCM-HP theory. Besides, the methods of deep learning would help us to improve our understanding about the relationship between herbal property and action, as well as to enrich and develop the theory of TCM-HP scientifically.

Preliminary Magnetostratigraphic Study of the Split Mountain and Lower Imperial Groups, Split Mountain Gorge, Western Salton Trough, CA

NASA Astrophysics Data System (ADS)

Fluette, A. L.; Housen, B. A.; Dorsey, R. J.

2004-12-01

We present preliminary results of a magnetostratigraphic study of Miocene-Pliocene sedimentary rocks of the Split Mt. and lower Imperial Groups exposed in Split Mt. Gorge and eastern Fish Creek-Vallecito basin, western Salton Trough. Precise age control for the base of this thick section is needed to improve our understanding of the early history of extension-related subsidence in this region. The geologic setting and stratigraphic framework are known from previous work by Dibblee (1954, 1996), Woodard (1963), Kerr (1982), Winker (1987), Kerr and Kidwell (1991), Winker and Kidwell (1986; 1996), and others. We have analyzed Upper Miocene to lower Pliocene strata exposed in a conformable section in Split Mt. Gorge, including (in order from the base; nomenclature of Winker and Kidwell, 1996): (1) Split Mt. Group: Red Rock Fm alluvial sandstone; Elephant Trees alluvial conglomerate; and lower megabreccia unit; and (2) lower part of Imperial Group, including: Fish Creek Gypsum; proximal to distal turbidites of the Latrania Fm and Wind Caves Mbr of Deguynos Fm; upper megabreccia unit; marine mudstone and rhythmites of the Mud Hills Mbr (Deguynos Fm); and the basal part of the Yuha Mbr (Deguynos Fm). Measured thickness from the base of the Elephant Trees Cgl to the base of the Yuha Mbr is about 1050 m, consistent with previous measurements of Winker (1987). Paleomagnetic samples were collected at approximately 10 m intervals throughout this section. The upper portion of our sampled section overlaps with the lower part of the section sampled for magnetostratigraphic study by Opdyke et al. (1977) and Johnson et al. (1983). They interpreted the base of their section to be about 4.3 Ma, and calculated an average sedimentation rate of approximately 5.5 mm/yr for the lower part of their section. Good-quality preliminary results from 15 paleomagnetic sites distributed throughout our sampled section permit preliminary identification of 6 polarity zones. Based on regional mapping and stratigraphic correlations (Winker and Kidwell, 1996) and extrapolation of the Johnson et al. (1983) sedimentation rates, we tentatively correlate two normal-polarity intervals in the lower part of our section to Chrons C3An.1n and C3An.2n of the geomagnetic polarity time scale of Cande and Kent (1995). If correct, this result would suggest that the lowest reversed-polarity portion of the Red Rock Fm near the base of the section should be correlated to Chron C3Ar.2r, and would be between 6.57 and 6.94 Ma in age. An alternative, but less likely, correlation for the reverse-polarity interval at the base of the section would be with Chron C2Br (7.09-7.43 Ma). This has significant implications for the timing of earliest extension-related basin formation in the western Salton Trough, and potentially raises new questions about the relationship of the Red Rock and Elephant Trees Formations to the Alverson Volcanics (22-14 Ma; Ruisaard, 1979; Kerr, 1982). These preliminary results will be tested and refined with a complete analysis of the remaining samples.

Development, optimization and validation of gas chromatographic fingerprinting of Brazilian commercial diesel fuel for quality control.

PubMed

dos Santos, Bruno César Diniz Brito; Flumignan, Danilo Luiz; de Oliveira, José Eduardo

2012-10-01

A three-step development, optimization and validation strategy is described for gas chromatography (GC) fingerprints of Brazilian commercial diesel fuel. A suitable GC-flame ionization detection (FID) system was selected to assay a complex matrix such as diesel. The next step was to improve acceptable chromatographic resolution with reduced analysis time, which is recommended for routine applications. Full three-level factorial designs were performed to improve flow rate, oven ramps, injection volume and split ratio in the GC system. Finally, several validation parameters were performed. The GC fingerprinting can be coupled with pattern recognition and multivariate regressions analyses to determine fuel quality and fuel physicochemical parameters. This strategy can also be applied to develop fingerprints for quality control of other fuel types.

Bose-Fermi symmetry in the odd-even gold isotopes

NASA Astrophysics Data System (ADS)

Thomas, T.; Régis, J.-M.; Jolie, J.; Heinze, S.; Albers, M.; Bernards, C.; Fransen, C.; Radeck, D.

2014-05-01

In this work the results of an in-beam experiment on 195Au are presented, yielding new spins, multipole mixing ratios, and new low-lying states essential for the understanding of this nucleus. The positive-parity states from this work together with compiled data from the available literature for 185-199Au are compared to Interacting Boson Fermion Model calculations employing the Spin(6) Bose-Fermi symmetry. The evolution of the parameters for the τ splitting and the J splitting reveals a smooth behavior. Thereby, a common description based on the Bose-Fermi symmetry is found for 189-199Au. Furthermore, the calculated E2 transition strengths are compared to experimental values with fixed effective boson and fermion charges for all odd-even gold isotopes, emphasizing that the Spin(6) Bose-Fermi symmetry is valid for the gold isotopes.

A Balanced Tri-band PD Based on Microstrip-slotline Transition Structure Embedded Complementary Split-ring Resonators

NASA Astrophysics Data System (ADS)

Chen, Lei; Li, Xiao Yan; Wei, Feng

2017-12-01

A balanced tri-band equal power divider (PD) is proposed based on a balanced stepped-impedance microstrip-slotline transition structure in this paper. Multi-band differential-mode (DM) responses can be realized by embedding multiple complementary split-ring resonators (CSRRs) into the slotline resonator. It is found that a high and wideband common-mode (CM) suppression can be achieved. Moreover, the center frequencies of the DM passbands are independent from the CM ones, which significantly simplifies the design procedure. In order to validate its practicalbility, a balanced PD with three DM passbands centred at 1.57, 2.5 and 3.5 GHz is fabricated and a good agreement between the simulated and measured results is observed. To our best knowledge, a balanced tri-band PD is the first ever reported.

The Design and Analysis of a Novel Split-H-Shaped Metamaterial for Multi-Band Microwave Applications

PubMed Central

Islam, Sikder Sunbeam; Faruque, Mohammad Rashed Iqbal; Islam, Mohammad Tariqul

2014-01-01

This paper presents the design and analysis of a novel split-H-shaped metamaterial unit cell structure that is applicable in a multi-band frequency range and that exhibits negative permeability and permittivity in those frequency bands. In the basic design, the separate split-square resonators are joined by a metal link to form an H-shaped unit structure. Moreover, an analysis and a comparison of the 1 × 1 array and 2 × 2 array structures and the 1 × 1 and 2 × 2 unit cell configurations were performed. All of these configurations demonstrate multi-band operating frequencies (S-band, C-band, X-band and Ku-band) with double-negative characteristics. The equivalent circuit model and measured result for each unit cell are presented to validate the resonant behavior. The commercially available finite-difference time-domain (FDTD)-based simulation software, Computer Simulation Technology (CST) Microwave Studio, was used to obtain the reflection and transmission parameters of each unit cell. This is a novel and promising design in the electromagnetic paradigm for its simplicity, scalability, double-negative characteristics and multi-band operation. PMID:28788116

A splitting scheme based on the space-time CE/SE method for solving multi-dimensional hydrodynamical models of semiconductor devices

NASA Astrophysics Data System (ADS)

Nisar, Ubaid Ahmed; Ashraf, Waqas; Qamar, Shamsul

2016-08-01

Numerical solutions of the hydrodynamical model of semiconductor devices are presented in one and two-space dimension. The model describes the charge transport in semiconductor devices. Mathematically, the models can be written as a convection-diffusion type system with a right hand side describing the relaxation effects and interaction with a self consistent electric field. The proposed numerical scheme is a splitting scheme based on the conservation element and solution element (CE/SE) method for hyperbolic step, and a semi-implicit scheme for the relaxation step. The numerical results of the suggested scheme are compared with the splitting scheme based on Nessyahu-Tadmor (NT) central scheme for convection step and the same semi-implicit scheme for the relaxation step. The effects of various parameters such as low field mobility, device length, lattice temperature and voltages for one-space dimensional hydrodynamic model are explored to further validate the generic applicability of the CE/SE method for the current model equations. A two dimensional simulation is also performed by CE/SE method for a MESFET device, producing results in good agreement with those obtained by NT-central scheme.

Transparent thin shield for radio frequency transmit coils.

PubMed

Rivera, Debra S; Schulz, Jessica; Siegert, Thomas; Zuber, Verena; Turner, Robert

2015-02-01

To identify a shielding material compatible with optical head-motion tracking for prospective motion correction and which minimizes radio frequency (RF) radiation losses at 7 T without sacrificing line-of-sight to an imaging target. We evaluated a polyamide mesh coated with silver. The thickness of the coating was approximated from the composition ratio provided by the material vendor and validated by an estimate derived from electrical conductivity and light transmission measurements. The performance of the shield is compared to a split-copper shield in the context of a four-channel transmit-only loop array. The mesh contains less than a skin-depth of silver coating (300 MHz) and attenuates light by 15 %. Elements of the array vary less in the presence of the mesh shield as compared to the split-copper shield indicating that the array behaves more symmetrically with the mesh shield. No degradation of transmit efficiency was observed for the mesh as compared to the split-copper shield. We present a shield compatible with future integration of camera-based motion-tracking systems. Based on transmit performance and eddy-current evaluations the mesh shield is appropriate for use at 7 T.

Mode transition coordinated control for a compound power-split hybrid car

NASA Astrophysics Data System (ADS)

Wang, Chen; Zhao, Zhiguo; Zhang, Tong; Li, Mengna

2017-03-01

With a compound power-split transmission directly connected to the engine in hybrid cars, dramatic fluctuations in engine output torque result in noticeable jerks when the car is in mode transition from electric drive mode to hybrid drive mode. This study designed a mode transition coordinated control strategy, and verified that strategy's effectiveness with both simulations and experiments. Firstly, the mode transition process was analyzed, and ride comfort issues during the mode transition process were demonstrated. Secondly, engine ripple torque was modeled using the measured cylinder pumping pressure when the engine was not in operation. The complete dynamic plant model of the power-split hybrid car was deduced, and its effectiveness was validated by a comparison of experimental and simulation results. Thirdly, a coordinated control strategy was designed to determine the desired engine torque, motor torque, and the moment of fuel injection. Active damping control with two degrees of freedom, based on reference output shaft speed estimation, was designed to mitigate driveline speed oscillations. Carrier torque estimation based on transmission kinematics and dynamics was used to suppress torque disturbance during engine cranking. The simulation and experimental results indicate that the proposed strategy effectively suppressed vehicle jerks and improved ride comfort during mode transition.

The Design and Analysis of a Novel Split-H-Shaped Metamaterial for Multi-Band Microwave Applications.

PubMed

Islam, Sikder Sunbeam; Faruque, Mohammad Rashed Iqbal; Islam, Mohammad Tariqul

2014-07-02

This paper presents the design and analysis of a novel split-H-shaped metamaterial unit cell structure that is applicable in a multi-band frequency range and that exhibits negative permeability and permittivity in those frequency bands. In the basic design, the separate split-square resonators are joined by a metal link to form an H-shaped unit structure. Moreover, an analysis and a comparison of the 1 × 1 array and 2 × 2 array structures and the 1 × 1 and 2 × 2 unit cell configurations were performed. All of these configurations demonstrate multi-band operating frequencies (S-band, C-band, X-band and K u -band) with double-negative characteristics. The equivalent circuit model and measured result for each unit cell are presented to validate the resonant behavior. The commercially available finite-difference time-domain (FDTD)-based simulation software, Computer Simulation Technology (CST) Microwave Studio, was used to obtain the reflection and transmission parameters of each unit cell. This is a novel and promising design in the electromagnetic paradigm for its simplicity, scalability, double-negative characteristics and multi-band operation.

Knowledge evolution in physics research: An analysis of bibliographic coupling networks.

PubMed

Liu, Wenyuan; Nanetti, Andrea; Cheong, Siew Ann

2017-01-01

Even as we advance the frontiers of physics knowledge, our understanding of how this knowledge evolves remains at the descriptive levels of Popper and Kuhn. Using the American Physical Society (APS) publications data sets, we ask in this paper how new knowledge is built upon old knowledge. We do so by constructing year-to-year bibliographic coupling networks, and identify in them validated communities that represent different research fields. We then visualize their evolutionary relationships in the form of alluvial diagrams, and show how they remain intact through APS journal splits. Quantitatively, we see that most fields undergo weak Popperian mixing, and it is rare for a field to remain isolated/undergo strong mixing. The sizes of fields obey a simple linear growth with recombination. We can also reliably predict the merging between two fields, but not for the considerably more complex splitting. Finally, we report a case study of two fields that underwent repeated merging and splitting around 1995, and how these Kuhnian events are correlated with breakthroughs on Bose-Einstein condensation (BEC), quantum teleportation, and slow light. This impact showed up quantitatively in the citations of the BEC field as a larger proportion of references from during and shortly after these events.

A Parallel, Finite-Volume Algorithm for Large-Eddy Simulation of Turbulent Flows

NASA Technical Reports Server (NTRS)

Bui, Trong T.

1999-01-01

A parallel, finite-volume algorithm has been developed for large-eddy simulation (LES) of compressible turbulent flows. This algorithm includes piecewise linear least-square reconstruction, trilinear finite-element interpolation, Roe flux-difference splitting, and second-order MacCormack time marching. Parallel implementation is done using the message-passing programming model. In this paper, the numerical algorithm is described. To validate the numerical method for turbulence simulation, LES of fully developed turbulent flow in a square duct is performed for a Reynolds number of 320 based on the average friction velocity and the hydraulic diameter of the duct. Direct numerical simulation (DNS) results are available for this test case, and the accuracy of this algorithm for turbulence simulations can be ascertained by comparing the LES solutions with the DNS results. The effects of grid resolution, upwind numerical dissipation, and subgrid-scale dissipation on the accuracy of the LES are examined. Comparison with DNS results shows that the standard Roe flux-difference splitting dissipation adversely affects the accuracy of the turbulence simulation. For accurate turbulence simulations, only 3-5 percent of the standard Roe flux-difference splitting dissipation is needed.

Validation of the MMPI-2 Low Self-Esteem Content Scale.

PubMed

Brems, C; Lloyd, P

1995-12-01

We explored the concurrent validity of the MMPI-2 Low Self-Esteem (LSE) Content scale by asking 216 undergraduate students to complete the Minnesota Multiphasic Personality Inventory-2 (Butcher, Dahlstrom, Graham, Tellegen, & Kaemmer, 1991), Harter Adult Self-Perception Profile (Harter, 1986a) and Rosenberg Self-Esteem Scale (Rosenberg, 1965). Results suggest the LSE renders a good assessment of global self-esteem as well as being a measure of three distinct components of self-esteem. These specific subscales, identified by factor analysis, were labeled Ineptitude, Negative Self-Value, and Negative Comparison with Others. The LSE and its subscales produced good internal consistency (alpha and Gutman Split Half) coefficients.

Numerical simulation of single bubble dynamics under acoustic travelling waves.

PubMed

Ma, Xiaojian; Huang, Biao; Li, Yikai; Chang, Qing; Qiu, Sicong; Su, Zheng; Fu, Xiaoying; Wang, Guoyu

2018-04-01

The objective of this paper is to apply CLSVOF method to investigate the single bubble dynamics in acoustic travelling waves. The Naiver-Stokes equation considering the acoustic radiation force is proposed and validated to capture the bubble behaviors. And the CLSVOF method, which can capture the continuous geometric properties and satisfies mass conservation, is applied in present work. Firstly, the regime map, depending on the dimensionless acoustic pressure amplitude and acoustic wave number, is constructed to present different bubble behaviors. Then, the time evolution of the bubble oscillation is investigated and analyzed. Finally, the effect of the direction and the damping coefficient of acoustic wave propagation on the bubble behavior are also considered. The numerical results show that the bubble presents distinct oscillation types in acoustic travelling waves, namely, volume oscillation, shape oscillation, and splitting oscillation. For the splitting oscillation, the formation of jet, splitting of bubble, and the rebound of sub-bubbles may lead to substantial increase in pressure fluctuations on the boundary. For the shape oscillation, the nodes and antinodes of the acoustic pressure wave contribute to the formation of the "cross shape" of the bubble. It should be noted that the direction of the bubble translation and bubble jet are always towards the direction of wave propagation. In addition, the damping coefficient causes bubble in shape oscillation to be of asymmetry in shape and inequality in size, and delays the splitting process. Copyright © 2017 Elsevier B.V. All rights reserved.

Fierz bilinear formulation of the Maxwell-Dirac equations and symmetry reductions

NASA Astrophysics Data System (ADS)

Inglis, Shaun; Jarvis, Peter

2014-09-01

We study the Maxwell-Dirac equations in a manifestly gauge invariant presentation using only the spinor bilinear scalar and pseudoscalar densities, and the vector and pseudovector currents, together with their quadratic Fierz relations. The internally produced vector potential is expressed via algebraic manipulation of the Dirac equation, as a rational function of the Fierz bilinears and first derivatives (valid on the support of the scalar density), which allows a gauge invariant vector potential to be defined. This leads to a Fierz bilinear formulation of the Maxwell tensor and of the Maxwell-Dirac equations, without any reference to gauge dependent quantities. We show how demanding invariance of tensor fields under the action of a fixed (but arbitrary) Lie subgroup of the Poincaré group leads to symmetry reduced equations. The procedure is illustrated, and the reduced equations worked out explicitly for standard spherical and cylindrical cases, which are coupled third order nonlinear PDEs. Spherical symmetry necessitates the existence of magnetic monopoles, which do not affect the coupled Maxwell-Dirac system due to magnetic terms cancelling. In this paper we do not take up numerical computations. As a demonstration of the power of our approach, we also work out the symmetry reduced equations for two distinct classes of dimension 4 one-parameter families of Poincaré subgroups, one splitting and one non-splitting. The splitting class yields no solutions, whereas for the non-splitting class we find a family of formal exact solutions in closed form.

Cryogenic on-chip multiplexer for the study of quantum transport in 256 split-gate devices

NASA Astrophysics Data System (ADS)

Al-Taie, H.; Smith, L. W.; Xu, B.; See, P.; Griffiths, J. P.; Beere, H. E.; Jones, G. A. C.; Ritchie, D. A.; Kelly, M. J.; Smith, C. G.

2013-06-01

We present a multiplexing scheme for the measurement of large numbers of mesoscopic devices in cryogenic systems. The multiplexer is used to contact an array of 256 split gates on a GaAs/AlGaAs heterostructure, in which each split gate can be measured individually. The low-temperature conductance of split-gate devices is governed by quantum mechanics, leading to the appearance of conductance plateaux at intervals of 2e2/h. A fabrication-limited yield of 94% is achieved for the array, and a "quantum yield" is also defined, to account for disorder affecting the quantum behaviour of the devices. The quantum yield rose from 55% to 86% after illuminating the sample, explained by the corresponding increase in carrier density and mobility of the two-dimensional electron gas. The multiplexer is a scalable architecture, and can be extended to other forms of mesoscopic devices. It overcomes previous limits on the number of devices that can be fabricated on a single chip due to the number of electrical contacts available, without the need to alter existing experimental set ups.

Improving multiphoton STED nanoscopy with separation of photons by LIfetime Tuning (SPLIT)

NASA Astrophysics Data System (ADS)

Coto Hernández, Iván.; Lanzano, Luca; Castello, Marco; Jowett, Nate; Tortarolo, Giorgio; Diaspro, Alberto; Vicidomini, Giuseppe

2018-02-01

Stimulated emission depletion (STED) microscopy is a powerful bio-imaging technique since it provides molecular spatial resolution whilst preserving the most important assets of fluorescence microscopy. When combined with twophoton excitation (2PE) microscopy (2PE-STED), the sub-diffraction imaging ability of STED microscopy can be achieved also on thick biological samples. The most straightforward implementation of 2PE-STED microscopy is obtained by introducing a STED beam operating in continuous wave (CW) into a conventional Ti:Sapphire based 2PE microscope (2PE-CW-STED). In this implementation, an effective resolution enhancement is mainly obtained implementing a time-gated detection scheme, which however can drastically reduce the signal-to-noise/background ratio of the final image. Herein, we combine the lifetime tuning (SPLIT) approach with 2PE-CW-STED to overcome this limitation. The SPLIT approach is employed to discard fluorescence photons lacking super-resolution information, by means of a pixel-by-pixel phasor approach. Combining the SPLIT approach with image deconvolution further optimizes the signal-to-noise/background ratio.

Coupling nanoliter high-performance liquid chromatography to inductively coupled plasma mass spectrometry for arsenic speciation.

PubMed

Cheng, Heyong; Shen, Lihuan; Liu, Jinhua; Xu, Zigang; Wang, Yuanchao

2018-04-01

Nanoliter high-performance liquid chromatography shows low consumption of solvents and samples, offering one of the best choices for arsenic speciation in precious samples in combination with inuctively coupled plasma mass spectrometry. A systematic investigation on coupling nanoliter high-performance liquid chromatography to inductively coupled plasma mass spectrometry from instrument design to injected sample volume and mobile phase was performed in this study. Nanoflow mobile phase was delivered by flow splitting using a conventional high-pressure pump with reuse of mobile phase waste. Dead volume was minimized to 60 nL for the sheathless interface based on the previously developed nanonebulizer. Capillary columns for nanoliter high-performance liquid chromatography were found to be sensitive to sample loading volume. An apparent difference was also found between the mobile phases for nanoliter and conventional high-performance liquid chromatography. Baseline separation of arsenite, arsenate, monomethylarsenic, and dimethylarsenic was achieved within 11 min on a 15 cm C 18 capillary column and within 12 min on a 25 cm strong anion exchange column. Detection limits of 0.9-1.8 μg/L were obtained with precisions variable in the range of 1.6-4.2%. A good agreement between determined and certified values of a certified reference material of human urine (GBW 09115) validated its accuracy along with good recoveries (87-102%). © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

ENZYME-LINKED IMMUNOSORBENT ASSAY FOR SCREENING DIOXIN SOIL CONTAMINATION BY UNCONTROLLED COMBUSTION DURING INFORMAL RECYCLING IN SLUMS

PubMed Central

Trindade, Mirta; Nording, Malin; Nichkova, Mikaela; Spinnel, Erik; Haglund, Peter; Last, Michael S.; Gee, Shirley; Hammock, Bruce; Last, Jerold A.; González-Sapienza, Gualberto; Brena, Beatriz M.

2010-01-01

Uncontrolled combustion due to garbage recycling is a widespread activity among slum dwellers in distressed economy countries and has been indicated as a major source of dioxin contamination. However, because of the high cost and complexity of gas chromatography/high-resolution mass spectrometry (GC-HRMS) analysis, the magnitude of the problem remains largely unknown. The present study describes a first approach toward the use of a dioxin antibody-based enzyme-linked immunosorbent assay (ELISA) as the basis for a sustainable, simple, and low-cost monitoring program to assess the toxicological impact of uncontrolled combustion in slums. A panel of 16 samples was analyzed by GC-HRMS and ELISA on split extracts. Close to 20% of the analyzed samples showed dioxin concentrations up to almost twice the guidance level for residential soil in several countries, pointing out the need for performing a large-scale monitoring program. Despite the potential for variations in dioxin congener distribution due to the mixed nature of the incinerated material, there was a good correlation between the toxic equivalents as determined by GC-HRMS and ELISA. Furthermore, an interlaboratory ELISA validation showed that the capacity to perform the dioxin ELISA was successfully transferred between laboratories. It was concluded that the ELISA method performed very well as a screening tool to prioritize samples for instrumental analysis, which allows cutting down costs significantly. PMID:18522475

Detection of borreliae in archived sera from patients with clinically suspect Lyme disease.

PubMed

Lee, Sin Hang; Vigliotti, Jessica S; Vigliotti, Veronica S; Jones, William; Shearer, David M

2014-03-11

The diagnoses of Lyme disease based on clinical manifestations, serological findings and detection of infectious agents often contradict each other. We tested 52 blind-coded serum samples, including 20 pre-treatment and 12 post-treatment sera from clinically suspect Lyme disease patients, for the presence of residual Lyme disease infectious agents, using nested PCR amplification of a signature segment of the borrelial 16S ribosomal RNA gene for detection and direct DNA sequencing of the PCR amplicon for molecular validation. These archived sera were split from the samples drawn for the 2-tier serology tests performed by a CDC-approved laboratory, and are used as reference materials for evaluating new diagnostic reagents. Of the 12 post-treatment serum samples, we found DNA evidence of a novel borrelia of uncertain significance in one, which was also positive for the 2-tier serology test. The rest of the post-treatment sera and all 20 control sera were PCR-negative. Of the 20 pre-treatment sera from clinically suspect early Lyme disease patients, we found Borrelia miyamotoi in one which was 2-tier serology-negative, and a Borrelia burgdorferi in two-one negative and one positive for 2-tier serology. We conclude that a sensitive and reliable DNA-based test is needed to support the diagnosis of Lyme disease and Lyme disease-like borreliosis.

Psychometric properties of stress and anxiety measures among nulliparous women.

PubMed

Bann, Carla M; Parker, Corette B; Grobman, William A; Willinger, Marian; Simhan, Hyagriv N; Wing, Deborah A; Haas, David M; Silver, Robert M; Parry, Samuel; Saade, George R; Wapner, Ronald J; Elovitz, Michal A; Miller, Emily S; Reddy, Uma M

2017-03-01

To examine the psychometric properties of three measures, the perceived stress scale (PSS), pregnancy experience scale (PES), and state trait anxiety inventory (STAI), for assessing stress and anxiety during pregnancy among a large sample of nulliparous women. The sample included 10,002 pregnant women participating in the Nulliparous Pregnancy Outcomes Study: Monitoring Mothers-to-Be (nMoM2b). Internal consistency reliability was assessed with Cronbach's alpha and factorial validity with confirmatory factor analyses. Intraclass correlations (ICCs) were calculated to determine stability of PSS scales over time. Psychometric properties were examined for the overall sample, as well as subgroups based on maternal age, race/ethnicity and language. All three scales demonstrated good internal consistency reliability. Confirmatory factor analyses supported the factor structures of the PSS and the PES. However, a one-factor solution of the trait-anxiety subscale from the STAI did not fit well; a two-factor solution, splitting the items into factors based on direction of item wording (positive versus negative) provided a better fit. Scores on the PSS were generally stable over time (ICC = 0.60). Subgroup analyses revealed a few items that did not perform well on Spanish versions of the scales. Overall, the scales performed well, suggesting they could be useful tools for identifying women experiencing high levels of stress and anxiety during pregnancy and allowing for the implementation of interventions to help reduce maternal stress and anxiety.

Factor Structure of the Psychopathic Personality Inventory (PPI): Findings from a Large Incarcerated Sample

PubMed Central

Neumann, Craig S.; Malterer, Melanie B.; Newman, Joseph P.

2010-01-01

Recent exploratory factor analysis (EFA) of the Psychopathic Personality Inventory (PPI; Lilienfeld, 1990) with a community sample suggested that the PPI subscales may be comprised of two higher-order factors (Benning et al., 2003). However, little research has examined the PPI structure in offenders. The current study attempted to replicate the Benning et al. two-factor solution using a large (N=1224) incarcerated male sample. Confirmatory factor analysis (CFA) of this model with the full sample resulted in poor model fit. Next, to identify a factor solution that would summarize the offender data, EFA was conducted using a split-half of the total sample, followed by an attempt to replicate the EFA solution via CFA with the other split-half sample. Using the recommendations of Prooijen and van der Kloot (2001) for recovering EFA solutions, model fit results provided some evidence that the EFA solution could be recovered via CFA. However, this model involved extensive cross-loadings of the subscales across three factors, suggesting item overlap across PPI subscales. In sum, the two-factor solution reported by Benning et al. (2003) was not a viable model for the current sample of offenders, and additional research is needed to elucidate the latent structure of the PPI. PMID:18557694

Stress, Social Support, and Psychosocial Functioning of Ethnically Diverse Students

ERIC Educational Resources Information Center

Farrell, Michelle; Langrehr, Kimberly J.

2017-01-01

This study examined the stress-buffering role of social support on indicators of psychosocial functioning among a combined and split sample of ethnically diverse college students. Although high social support significantly moderated 2 relationships in the combined sample, high and low levels of social support significantly reduced the effect of…

Exploratory and Confirmatory Analysis of the Trauma Practices Questionnaire

ERIC Educational Resources Information Center

Craig, Carlton D.; Sprang, Ginny

2009-01-01

Objective: The present study provides psychometric data for the Trauma Practices Questionnaire (TPQ). Method: A nationally randomized sample of 2,400 surveys was sent to self-identified trauma treatment specialists, and 711 (29.6%) were returned. Results: An exploratory factor analysis (N = 319) conducted on a randomly split sample (RSS) revealed…

Results of quality-control sampling of water, bed sediment, and tissue in the Western Lake Michigan Drainages study unit of the National Water-Quality Assessment Program

USGS Publications Warehouse

Fitzgerald, S.A.

1997-01-01

This report contains the quality control results of the Western Lake Michigan Drainages study unit of the National Water Quality Assessment Program. Quality control samples were collected in the same manner and contemporaneously with environmental samples during the first highintensity study phase in the unit (1992 through 1995) and amounted to approximately 15 percent of all samples collected. The accuracy and precision of hundreds of chemical analyses of surface and ground-water, bed sediment, and tissue was determined through the collection and analysis of field blanks, field replicates and splits, matrix spikes, and surrogates. Despite the several detections of analytes in the field blanks, the concentrations of most constituents in the environmental samples will likely be an order of magnitude or higher than those in the blanks. However, frequent detections, and high concentrations, of dissolved organic carbon (DOC) in several surface and ground-water blanks are probably significant with respect to commonly measured environmental concentrations, and the environmental data will have to be qualified accordingly. The precision of sampling of water on a percent basis, as determined from replicates and splits, was generally proportional to the concentration of the constituents, with constituents present in relatively high concentrations generally having less sampling variability than those with relatively low concentrations. In general, analytes with relatively high variability between replicates were present at concentrations near the reporting limit or were associated with relatively small absolute concentration differences, or both. Precision of replicates compared to that for splits in bed sediment samples was similar, thus eliminating sampling as a major source of variability in analyte concentrations. In the case the phthalates in bed sediment, contamination in either the field or laboratory could have caused the relatively large variability between replicate samples and between split samples.Variability of analyte concentrations in tissue samples was relatively low, being 29 percent or less for all constituents. Recoveries of most laboratory schedule 2001/2010 pesticide spike compounds in surfacewater samples were reasonably good. Low intrinsic method recovery resulted in relatively low recovery forp,p'-DDE, metribuzin, and propargite. In the case of propargite, decomposition with the environmental sample matrices was also indicated. Recoveries of two compounds, cyanazine and thiobencarb, might have been biased high due to interferences. The one laboratory schedule 2050/2051 field matrix pesticide spike indicated numerous operational problems with this method that biased recoveries either low or high. Recoveries of pesticides from both pesticide schedules in field spikes of ground-water samples generally were similar to those of field matrix spikes of surface- water samples. High maximum recoveries were noted for tebuthiuron, disulfoton, DCPA, and permethrin, which indicates the possible presence of interferents in the matrices for these compounds. Problems in the recoveries of pesticides on schedule 2050/2051 from ground-water samples generally were the same as those for surfacewater samples. Recoveries of VOCs in field matrix spikes were reasonable when consideration was given for the use of the micropipettor that delivered only about 80 percent on average of the nominal mass of spiked analytes. Finally, the recoveries of most surrogate compounds in surface and ground-water samples were reasonable. Problems in sample handling (for example, spillage) were likely not the cause of any of the low recoveries of spiked compounds.

A cooperative-binding split aptamer assay for rapid, specific and ultra-sensitive fluorescence detection of cocaine in saliva† †Electronic supplementary information (ESI) available: Optimization of Mg2+ and ATMND concentrations for our CBSA-based ATMND-binding assay; ATMND-reported calibration curve for CBSA-5325 at various cocaine concentrations; ATMND binding affinity for the cocaine-assembled CBSA-5325; K D of 38-GC and different 38-GC mutants for cocaine as characterized by ITC; stem length effects on cocaine-induced CBSA assembly; spectra of CBSA-5335-based fluorescence detection of cocaine in 1× binding buffer; characterization of cocaine binding affinity of CBSA-5335 and PSA using ITC; fluorescence detection of cocaine in saliva with our fluorophore/quencher modified CBSA-5335; calibration curve of our CBSA-5335-based fluorophore/quencher assay in 1× binding buffer and 10% saliva at cocaine concentrations ranging from 0 to 10 μM; bias and precision of the CBSA-5335-based fluorophore/quencher assay; comparison of amplification-free split-aptamer assays for cocaine detection; sequence ID and DNA sequences used in this work. See DOI: 10.1039/c6sc01833e Click here for additional data file.

PubMed Central

Yu, Haixiang; Canoura, Juan; Guntupalli, Bhargav; Lou, Xinhui

2017-01-01

Sensors employing split aptamers that reassemble in the presence of a target can achieve excellent specificity, but the accompanying reduction of target affinity mitigates any overall gains in sensitivity. We for the first time have developed a split aptamer that achieves enhanced target-binding affinity through cooperative binding. We have generated a split cocaine-binding aptamer that incorporates two binding domains, such that target binding at one domain greatly increases the affinity of the second domain. We experimentally demonstrate that the resulting cooperative-binding split aptamer (CBSA) exhibits higher target binding affinity and is far more responsive in terms of target-induced aptamer assembly compared to the single-domain parent split aptamer (PSA) from which it was derived. We further confirm that the target-binding affinity of our CBSA can be affected by the cooperativity of its binding domains and the intrinsic affinity of its PSA. To the best of our knowledge, CBSA-5335 has the highest cocaine affinity of any split aptamer described to date. The CBSA-based assay also demonstrates excellent performance in target detection in complex samples. Using this CBSA, we achieved specific, ultra-sensitive, one-step fluorescence detection of cocaine within fifteen minutes at concentrations as low as 50 nM in 10% saliva without signal amplification. This limit of detection meets the standards recommended by the European Union's Driving under the Influence of Drugs, Alcohol and Medicines program. Our assay also demonstrates excellent reproducibility of results, confirming that this CBSA-platform represents a robust and sensitive means for cocaine detection in actual clinical samples. PMID:28451157

Identification of the substrate radical intermediate derived from ethanolamine during catalysis by ethanolamine ammonia-lyase.

PubMed

Bender, Güneş; Poyner, Russell R; Reed, George H

2008-10-28

Rapid-mix freeze-quench (RMFQ) methods and electron paramagnetic resonance (EPR) spectroscopy have been used to characterize the steady-state radical in the deamination of ethanolamine catalyzed by adenosylcobalamin (AdoCbl)-dependent ethanolamine ammonia-lyase (EAL). EPR spectra of the radical intermediates formed with the substrates, [1-13C]ethanolamine, [2-13C]ethanolamine, and unlabeled ethanolamine were acquired using RMFQ trapping methods from 10 ms to completion of the reaction. Resolved 13C hyperfine splitting in EPR spectra of samples prepared with [1-13C]ethanolamine and the absence of such splitting in spectra of samples prepared with [2-13C]ethanolamine show that the unpaired electron is localized on C1 (the carbinol carbon) of the substrate. The 13C splitting from C1 persists from 10 ms throughout the time course of substrate turnover, and there was no evidence of a detectable amount of a product like radical having unpaired spin on C2. These results correct an earlier assignment for this radical intermediate [Warncke, K., et al. (1999) J. Am. Chem. Soc. 121, 10522-10528]. The EPR signals of the substrate radical intermediate are altered by electron spin coupling to the other paramagnetic species, cob(II)alamin, in the active site. The dipole-dipole and exchange interactions as well as the 1-13C hyperfine splitting tensor were analyzed via spectral simulations. The sign of the isotropic exchange interaction indicates a weak ferromagnetic coupling of the two unpaired electrons. A Co2+-radical distance of 8.7 A was obtained from the magnitude of the dipole-dipole interaction. The orientation of the principal axes of the 13C hyperfine splitting tensor shows that the long axis of the spin-bearing p orbital on C1 of the substrate radical makes an angle of approximately 98 degrees with the unique axis of the d(z2) orbital of Co2+.

Adsorption site analysis of impurity embedded single-walled carbon nanotube bundles

USGS Publications Warehouse

Agnihotri, S.; Mota, J.P.B.; Rostam-Abadi, M.; Rood, M.J.

2006-01-01

Bundle morphology and adsorptive contributions from nanotubes and impurities are studied both experimentally and by simulation using a computer-aided methodology, which employs a small physisorbed probe molecule to explore the porosity of nanotube samples. Grand canonical Monte Carlo simulation of nitrogen adsorption on localized sites of a bundle is carried out to predict adsorption in its accessible internal pore volume and on its external surface as a function of tube diameter. External adsorption is split into the contributions from the clean surface of the outermost nanotubes of the bundle and from the surface of the impurities. The site-specific isotherms are then combined into a global isotherm for a given sample using knowledge of its tube-diameter distribution obtained by Raman spectroscopy. The structural parameters of the sample, such as the fraction of open-ended nanotubes and the contributions from impurities and nanotube bundles to total external surface area, are determined by fitting the experimental nitrogen adsorption data to the simulated isotherm. The degree of closure between experimental and calculated adsorption isotherms for samples manufactured by two different methods, to provide different nanotube morphology and contamination level, further strengthens the validity and resulting interpretations based on the proposed approach. The average number of nanotubes per bundle and average bundle size, within a sample, are also quantified. The proposed method allows for extrapolation of adsorption properties to conditions where the purification process is 100% effective at removing all impurities and opening access to all intrabundle adsorption sites. ?? 2006 Elsevier Ltd. All rights reserved.

Silicon Nitride for Direct Water-Splitting and Corrosion Mitigation

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

Head, J.; Turner, J.A.

2006-01-01

Todays fossil fuels are becoming harder to obtain, creating pollution problems, and posing hazards to people’s health. One alternative to fossil fuels is hydrogen, capable of serving as a clean and efficient energy carrier. Certain semiconductors are able to harness the energy of photons and direct it into water electrolysis in a process known as photoelectrochemical water splitting. Triple junction devices integrate three semiconductors of different band gaps resulting in a monolithic material that absorbs over a broader spectrum. Amorphous silicon (a-Si) is one such material that, when stacked in tandem, possesses water-splitting capabilities. Even though a-Si is capable ofmore » splitting water, it is an unstable material in solution and therefore requires a coating to protect the surface from corrosion. A stable, transparent material that has the potential for corrosion protection is silicon nitride. In this study, silicon nitride thin films were grown using DC magnetron sputtering with varying amounts of argon and nitrogen added to the system. X-ray diffraction indicated amorphous silicon nitride films. Current as a function of potential was determined from cyclic voltammetry measurements. Mott-Schottky analysis showed n-type behavior with absorption and transmission measurements indicated variation in flatband potentials. Variation in band gap values ranging from 1.90 to 4.0 eV. Corrosion measurements reveal that the silicon nitride samples exhibit both p-type and n-type behavior. Photocurrent over a range of potentials was greater in samples that were submerged in acidic electrolyte. Silicon nitride shows good stability in acidic, neutral, and basic solutions, indicative of a good material for corrosion mitigation.« less

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

none,

Oak Ridge Associated Universities (ORAU), under the Oak Ridge Institute for Science and Education (ORISE) contract, collected split surface water samples with Nuclear Fuel Services (NFS) representatives on June 12, 2013. Representatives from the U.S. Nuclear Regulatory Commission (NRC) and the Tennessee Department of Environment and Conservation were also in attendance. Samples were collected at four surface water stations, as required in the approved Request for Technical Assistance number 11-018. These stations included Nolichucky River upstream (NRU), Nolichucky River downstream (NRD), Martin Creek upstream (MCU), and Martin Creek downstream (MCD). Both ORAU and NFS performed gross alpha and gross betamore » analyses, and Table 1 presents the comparison of results using the duplicate error ratio (DER), also known as the normalized absolute difference. A DER ≤ 3 indicates at a 99% confidence interval that split sample results do not differ significantly when compared to their respective one standard deviation (sigma) uncertainty (ANSI N42.22). The NFS split sample report specifies 95% confidence level of reported uncertainties (NFS 2013). Therefore, standard two sigma reporting values were divided by 1.96. In conclusion, most DER values were less than 3 and results are consistent with low (e.g., background) concentrations. The gross beta result for sample 5198W0014 was the exception. The ORAU gross beta result of 6.30 ± 0.65 pCi/L from location NRD is well above NFS's non-detected result of 1.56 ± 0.59 pCi/L. NFS's data package includes no detected result for any radionuclide at location NRD. At NRC's request, ORAU performed gamma spectroscopic analysis of sample 5198W0014 to identify analytes contributing to the relatively elevated gross beta results. This analysis identified detected amounts of naturally-occurring constituents, most notably Ac-228 from the thorium decay series, and does not suggest the presence of site-related contamination.« less

Metabolic profiling using HPLC allows classification of drugs according to their mechanisms of action in HL-1 cardiomyocytes

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

Strigun, Alexander; Wahrheit, Judith; Beckers, Simone

Along with hepatotoxicity, cardiotoxic side effects remain one of the major reasons for drug withdrawals and boxed warnings. Prediction methods for cardiotoxicity are insufficient. High content screening comprising of not only electrophysiological characterization but also cellular molecular alterations are expected to improve the cardiotoxicity prediction potential. Metabolomic approaches recently have become an important focus of research in pharmacological testing and prediction. In this study, the culture medium supernatants from HL-1 cardiomyocytes after exposure to drugs from different classes (analgesics, antimetabolites, anthracyclines, antihistamines, channel blockers) were analyzed to determine specific metabolic footprints in response to the tested drugs. Since most drugsmore » influence energy metabolism in cardiac cells, the metabolite 'sub-profile' consisting of glucose, lactate, pyruvate and amino acids was considered. These metabolites were quantified using HPLC in samples after exposure of cells to test compounds of the respective drug groups. The studied drug concentrations were selected from concentration response curves for each drug. The metabolite profiles were randomly split into training/validation and test set; and then analysed using multivariate statistics (principal component analysis and discriminant analysis). Discriminant analysis resulted in clustering of drugs according to their modes of action. After cross validation and cross model validation, the underlying training data were able to predict 50%-80% of conditions to the correct classification group. We show that HPLC based characterisation of known cell culture medium components is sufficient to predict a drug's potential classification according to its mode of action.« less

Development and psychometric testing of a new instrument to measure the caring behaviour of nurses in Italian acute care settings.

PubMed

Piredda, Michela; Ghezzi, Valerio; Fenizia, Elisa; Marchetti, Anna; Petitti, Tommasangelo; De Marinis, Maria Grazia; Sili, Alessandro

2017-12-01

To develop and psychometrically test the Italian-language Nurse Caring Behaviours Scale, a short measure of nurse caring behaviour as perceived by inpatients. Patient perceptions of nurses' caring behaviours are a predictor of care quality. Caring behaviours are culture-specific, but no measure of patient perceptions has previously been developed in Italy. Moreover, existing tools show unclear psychometric properties, are burdensome for respondents, or are not widely applicable. Instrument development and psychometric testing. Item generation included identifying and adapting items from existing measures of caring behaviours as perceived by patients. A pool of 28 items was evaluated for face validity. Content validity indexes were calculated for the resulting 15-item scale; acceptability and clarity were pilot tested with 50 patients. To assess construct validity, a sample of 2,001 consecutive adult patients admitted to a hospital in 2014 completed the scale and was split into two groups. Reliability was evaluated using nonlinear structural equation modelling coefficients. Measurement invariance was tested across subsamples. Item 15 loaded poorly in the exploratory factor analysis (n = 983) and was excluded from the final solution, positing a single latent variable with 14 indicators. This model fitted the data moderately. The confirmatory factor analysis (n = 1018) returned similar results. Internal consistency was excellent in both subsamples. Full scalar invariance was reached, and no significant latent mean differences were detected across subsamples. The new instrument shows reasonable psychometric properties and is a promising short and widely applicable measure of inpatient perceptions of nurse caring behaviours. © 2017 John Wiley & Sons Ltd.

Tank 30 and 37 Supernatant Sample Cross-Check and Evaporator Feed Qualification Analysis-2012

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

Oji, L. N.

2013-03-07

This report summarizes the analytical data reported by the F/H and Savannah River National Laboratories for the 2012 cross-check analysis for high level waste supernatant liquid samples from SRS Tanks 30 and 37. The intent of this Tank 30 and 37 sample analyses was to perform cross-checks against routine F/H Laboratory analyses (corrosion and evaporator feed qualification programs) using samples collected at the same time from both tanks as well as split samples from the tanks.

Design, Fabrication, and Validation of an Ultra-Lightweight Membrane Mirror (Conference Proceedings)

DTIC Science & Technology

2005-08-01

Membrane Mirror Active boundary control is very promising and studies predict good control over astigmatism and coma aberrations. However, the primary...design analysis. The mount has a split lenticular setup, allowing one canopy and many membrane mirrors that can be interchanged. The mount has a...spherical aberration, which is as expected. Results from finite element modeling showed that astigmatism can be corrected with the normal actuators

Electrodisintegration of Li 6

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

Bishop, G. R.; Bernheim, M.

1963-06-01

For the ( γ,n) reaction in Li 6 a model in which Li 6 splits into a deuteron and an alpha particle that separately absorb the photon energy was recently proposed. The model was tested by studying the inelastic scattering of 101.4-Mev electrons from Li 6. Expressions for the cross sections were obtained, and values calculated for a form factor in the cross sections confirm the validity of the model.

Split D Differential Probe Model Validation Using an Impedance Analyzer (Preprint)

DTIC Science & Technology

2014-02-01

AIR FORCE RESEARCH LABORATORY MATERIALS AND MANUFACTURING DIRECTORATE WRIGHT-PATTERSON AIR FORCE BASE, OH 45433-7750 AIR FORCE MATERIEL COMMAND... manufacture , use, or sell any patented invention that may relate to them. This report was cleared for public release by the USAF 88th Air Base Wing (88...Materials Division Materials and Manufacturing Directorate This report is published in the interest of scientific and technical information

Expansion of the wilderness values scale with three sub-scales: Personal maintenance, expression and learning, and societal maintenance

Treesearch

Rudy M. Schuster; Ken Cordell; Gary T. Green

2007-01-01

The purpose of this research was to expand the wilderness value scale administered in the 1994 and 2000 versions of the National Survey on Recreation and the Environment using questions included in the 2003 NSRE. A data set of 1,900 cases was randomly split in half. Validity of the additional questions was tested using principal component analysis, a confirmatory...

Development of classification models for identifying "true" P-glycoprotein (P-gp) inhibitors through inhibition, ATPase activation and monolayer efflux assays.

PubMed

Rapposelli, Simona; Coi, Alessio; Imbriani, Marcello; Bianucci, Anna Maria

2012-01-01

P-glycoprotein (P-gp) is an efflux pump involved in the protection of tissues of several organs by influencing xenobiotic disposition. P-gp plays a key role in multidrug resistance and in the progression of many neurodegenerative diseases. The development of new and more effective therapeutics targeting P-gp thus represents an intriguing challenge in drug discovery. P-gp inhibition may be considered as a valid approach to improve drug bioavailability as well as to overcome drug resistance to many kinds of tumours characterized by the over-expression of this protein. This study aims to develop classification models from a unique dataset of 59 compounds for which there were homogeneous experimental data on P-gp inhibition, ATPase activation and monolayer efflux. For each experiment, the dataset was split into a training and a test set comprising 39 and 20 molecules, respectively. Rational splitting was accomplished using a sphere-exclusion type algorithm. After a two-step (internal/external) validation, the best-performing classification models were used in a consensus predicting task for the identification of compounds named as "true" P-gp inhibitors, i.e., molecules able to inhibit P-gp without being effluxed by P-gp itself and simultaneously unable to activate the ATPase function.

A study of nitrogen incorporation in pyramidal site-controlled quantum dots

PubMed Central

2011-01-01

We present the results of a study of nitrogen incorporation in metalorganic-vapour-phase epitaxy-grown site-controlled quantum dots (QDs). We report for the first time on a significant incorporation (approximately 0.3%), producing a noteworthy red shift (at least 50 meV) in some of our samples. Depending on the level of nitrogen incorporation/exposure, strong modifications of the optical features are found (variable distribution of the emission homogeneity, fine-structure splitting, few-particle effects). We discuss our results, especially in relation to a specific reproducible sample which has noticeable features: the usual pattern of the excitonic transitions is altered and the fine-structure splitting is suppressed to vanishing values. Distinctively, nitrogen incorporation can be achieved without detriment to the optical quality, as confirmed by narrow linewidths and photon correlation spectroscopy. PMID:22029752

A simple weighted scoring system to guide surgical decision-making in patients with parapneumonic pleural effusion.

PubMed

Chang, Che-Chia; Chen, Tzu-Ping; Yeh, Chi-Hsiao; Huang, Pin-Fu; Wang, Yao-Chang; Yin, Shun-Ying

2016-11-01

The selection of ideal candidates for surgical intervention among patients with parapneumonic pleural effusion remains challenging. In this retrospective study, we sought to identify the main predictors of surgical treatment and devise a simple scoring system to guide surgical decision-making. Between 2005 and 2014, we identified 276 patients with parapneumonic pleural effusion. Patients in the training set (n=201) were divided into two groups according to their treatment modality (non-surgery vs. surgery). Using multivariable logistic regression analysis, we devised a scoring system to guide surgical decision-making. The score was subsequently validated in an independent set of 75 patients. A white blood cell count >13,500/µL, pleuritic pain, loculations, and split pleura sign were identified as independent predictors of surgical treatment. A weighted score based on these factors was devised, as follows: white blood cell count >13,500/µL (one point), pleuritic pain (one point), loculations (two points), and split pleura sign (three points). A score >4 was associated with a surgical approach with a sensitivity of 93.4%, a specificity of 82.4%, and an area under curve (AUC) of 0.879 (95% confidence interval: 0.828-0.930). In the validation set, a sensitivity of 94.3% and a specificity of 79.6% were found (AUC=0.869). The proposed scoring system reliably identifies patients with parapneumonic pleural effusion who are candidates for surgery. Pending independent external validation, our score may inform the appropriate use of surgical interventions in this clinical setting.

Classification of malignant and benign liver tumors using a radiomics approach

NASA Astrophysics Data System (ADS)

Starmans, Martijn P. A.; Miclea, Razvan L.; van der Voort, Sebastian R.; Niessen, Wiro J.; Thomeer, Maarten G.; Klein, Stefan

2018-03-01

Correct diagnosis of the liver tumor phenotype is crucial for treatment planning, especially the distinction between malignant and benign lesions. Clinical practice includes manual scoring of the tumors on Magnetic Resonance (MR) images by a radiologist. As this is challenging and subjective, it is often followed by a biopsy. In this study, we propose a radiomics approach as an objective and non-invasive alternative for distinguishing between malignant and benign phenotypes. T2-weighted (T2w) MR sequences of 119 patients from multiple centers were collected. We developed an efficient semi-automatic segmentation method, which was used by a radiologist to delineate the tumors. Within these regions, features quantifying tumor shape, intensity, texture, heterogeneity and orientation were extracted. Patient characteristics and semantic features were added for a total of 424 features. Classification was performed using Support Vector Machines (SVMs). The performance was evaluated using internal random-split cross-validation. On the training set within each iteration, feature selection and hyperparameter optimization were performed. To this end, another cross validation was performed by splitting the training sets in training and validation parts. The optimal settings were evaluated on the independent test sets. Manual scoring by a radiologist was also performed. The radiomics approach resulted in 95% confidence intervals of the AUC of [0.75, 0.92], specificity [0.76, 0.96] and sensitivity [0.52, 0.82]. These approach the performance of the radiologist, which were an AUC of 0.93, specificity 0.70 and sensitivity 0.93. Hence, radiomics has the potential to predict the liver tumor benignity in an objective and non-invasive manner.

[Reliability and validity of Meaningful Life Measure-Chinese Revised in Chinese college students].

PubMed

Xiao, Rong; Lai, Qiao-Zhen; Yang, Jia-Ping

2016-04-20

To test the reliability and validity of Meaningful Life Measure-Chinese Revised (MLM-CR) in Chinese college students. A total of 1035 college students were evaluated with MLM-CR, Satisfaction with Life Scale (SWLS), Purpose in Life (PIL) and Patient Health Questionnaire-2 (PHQ-2), and 120 of the students were examined with PIL-SF twice. All the items in MLM-CR had good discrimination indexes (r=0.753-0.838, P<0.001). Confirmatory factor analysis confirmed the hypothesized five-factor model of MLM-CR (Χ 2 /df=3.4, GFI=0.946, AGFI=0.924, RMR=0.069, NFI=0.953, CFI=0.966, RMSEA=0.048). The total internal consistency reliability of MLM-CR was 0.942, and the alpha coefficients of the 5 dimensions ranged from 0.782 to 0.877; the total split-half reliability was 0.920, and the split-half reliability of the 5 dimensions ranged from 0.752 to 0.830; the total test-retest reliability was 0.871, and the test-retest reliability of the 5 dimensions ranged from 0.783 to 0.805. The criterion validity of MLM-CR in correlation with SWLS, PIL and PHQ-2 was 0.66, 0.755 and -0.388, respectively (P<0.01). The Average score of MLM-CR of the college students was 5.20∓0.90, and the scores were significantly higher in female students than in the male students (P<0.001). MLM-CR has good psychometric properties for application in comprehensive evaluation of personal meaning in life.

[Evaluation on the validity and reliability of the Diabetes Self-management Knowledge, Attitude, and Behavior Assessment Scale (DSKAB)].

PubMed

Liu, Xiaoli; Dai, Long; Chen, Bo; Feng, Nongping; Wu, Qianhui; Lin, Yonghai; Zhang, Lan; Tan, Dong; Zhang, Jinhua; Tu, Huijuan; Li, Changfeng; Wang, Wenjuan

2016-01-01

To evaluate the validity and reliability of Diabetes Self-management Knowledge, Attitude, and Behavior Assessment Scale (DSKAB). We selected 460 patients with diabetes in the community, used the scale which was after two rounds of the Delphi method and pilot study. Investigators surveyed the patients by the way of face to face. by draw lots, we selected 25 community diabetes randomly for repeating investigations after one week. The validity analyses included face validity, content validity, construct validity and discriminant validity. The reliability analyses included Cronbach's α coefficient, θ coefficient, Ω coefficient, split-half reliability and test-retest reliability. This study distributed a total of 460 questionnaires, reclaimed 442, qualified 432. The score of the scale was 254.59 ± 28.90, the scores of the knowledge, attitude, behavior sub-scales were 82.44 ± 11.24, 63.53 ± 5.77 and 108.61 ± 17.55, respectively. It had excellent face validity and content validity. The correlation coefficient was from 0.71 to 0.91 among three sub-scales and the scale, P<0.001. The common factor cumulative variance contribution rate of the scale and three sub-scales was from 57.28% to 67.19%, which achieved more than 50% of the approved standard, there was 25 common factors, 91 items of the total 98 items held factor loading ≥0.40 in its relevant common factor, it had good construct validity. The scores of high group and low group in three sub-scales were: knowledge (91.12 ± 3.62) and (69.96 ± 11.20), attitude (68.75 ± 4.51) and (58.79 ± 4.87), behavior (129.38 ± 8.53) and (89.65 ± 11.34),mean scores of three sub-scales were apparently different, which compared between high score group and low score group, the t value were - 19.45, -16.24 and -30.29, respectively, P<0.001, and it had good discriminant validity. The Cronbach's α coefficient of the scale and three sub-scales was from 0.79 to 0.93, the θ coefficient was from 0.86 to 0.95, the Ω coefficient was from 0.90 to 0.98, split-half reliability was from 0.89 to 0.95.Test-retest reliability of the scale was 0.51;the three sub-scales was from 0.46 to 0.52, P<0.05. The validity and reliability of the Diabetes Self-management Knowledge, Attitude, and Behavior Assessment Scale are excellent, which is a suitable instrument to evaluate the self-management for patients with diabetes.

Assessing a Top-Down Modeling Approach for Seasonal Scale Snow Sensitivity

NASA Astrophysics Data System (ADS)

Luce, C. H.; Lute, A.

2017-12-01

Mechanistic snow models are commonly applied to assess changes to snowpacks in a warming climate. Such assessments involve a number of assumptions about details of weather at daily to sub-seasonal time scales. Models of season-scale behavior can provide contrast for evaluating behavior at time scales more in concordance with climate warming projections. Such top-down models, however, involve a degree of empiricism, with attendant caveats about the potential of a changing climate to affect calibrated relationships. We estimated the sensitivity of snowpacks from 497 Snowpack Telemetry (SNOTEL) stations in the western U.S. based on differences in climate between stations (spatial analog). We examined the sensitivity of April 1 snow water equivalent (SWE) and mean snow residence time (SRT) to variations in Nov-Mar precipitation and average Nov-Mar temperature using multivariate local-fit regressions. We tested the modeling approach using a leave-one-out cross-validation as well as targeted two-fold non-random cross-validations contrasting, for example, warm vs. cold years, dry vs. wet years, and north vs. south stations. Nash-Sutcliffe Efficiency (NSE) values for the validations were strong for April 1 SWE, ranging from 0.71 to 0.90, and still reasonable, but weaker, for SRT, in the range of 0.64 to 0.81. From these ranges, we exclude validations where the training data do not represent the range of target data. A likely reason for differences in validation between the two metrics is that the SWE model reflects the influence of conservation of mass while using temperature as an indicator of the season-scale energy balance; in contrast, SRT depends more strongly on the energy balance aspects of the problem. Model forms with lower numbers of parameters generally validated better than more complex model forms, with the caveat that pseudoreplication could encourage selection of more complex models when validation contrasts were weak. Overall, the split sample validations confirm transferability of the relationships in space and time contingent upon full representation of validation conditions in the calibration data set. The ability of the top-down space-for-time models to predict in new time periods and locations lends confidence to their application for assessments and for improving finer time scale models.

Split off-specular reflection and surface scattering from woven materials

NASA Astrophysics Data System (ADS)

Pont, Sylvia C.; Koenderink, Jan J.

2003-03-01

We measured radiance distributions for black lining cloth and copper gauze using the convenient technique of wrapping the materials around a circular cylinder, irradiating it with a parallel light source and collecting the scattered radiance by a digital camera. One family of parallel threads (weave or weft) was parallel to the cylinder generator. The most salient features for such glossy plane weaves are a splitting up of the reflection peak due to the wavy variations in local slopes of the threads around the cylinders and a surface scattering lobe due to the threads that run along the cylinder. These scattering characteristics are quite different from the (off-)specular peaks and lobes that were found before for random rough specular surfaces. The split off-specular reflection is due to the regular structures in our samples of man-made materials. We derived simple approximations for these reflectance characteristics using geometrical optics.

Rapid and controllable flame reduction of TiO2 nanowires for enhanced solar water-splitting.

PubMed

Cho, In Sun; Logar, Manca; Lee, Chi Hwan; Cai, Lili; Prinz, Fritz B; Zheng, Xiaolin

2014-01-08

We report a new flame reduction method to generate controllable amount of oxygen vacancies in TiO2 nanowires that leads to nearly three times improvement in the photoelectrochemical (PEC) water-splitting performance. The flame reduction method has unique advantages of a high temperature (>1000 °C), ultrafast heating rate, tunable reduction environment, and open-atmosphere operation, so it enables rapid formation of oxygen vacancies (less than one minute) without damaging the nanowire morphology and crystallinity and is even applicable to various metal oxides. Significantly, we show that flame reduction greatly improves the saturation photocurrent densities of TiO2 nanowires (2.7 times higher), α-Fe2O3 nanowires (9.4 times higher), ZnO nanowires (2.0 times higher), and BiVO4 thin film (4.3 times higher) in comparison to untreated control samples for PEC water-splitting applications.

One-dimensional high-order compact method for solving Euler's equations

NASA Astrophysics Data System (ADS)

Mohamad, M. A. H.; Basri, S.; Basuno, B.

2012-06-01

In the field of computational fluid dynamics, many numerical algorithms have been developed to simulate inviscid, compressible flows problems. Among those most famous and relevant are based on flux vector splitting and Godunov-type schemes. Previously, this system was developed through computational studies by Mawlood [1]. However the new test cases for compressible flows, the shock tube problems namely the receding flow and shock waves were not investigated before by Mawlood [1]. Thus, the objective of this study is to develop a high-order compact (HOC) finite difference solver for onedimensional Euler equation. Before developing the solver, a detailed investigation was conducted to assess the performance of the basic third-order compact central discretization schemes. Spatial discretization of the Euler equation is based on flux-vector splitting. From this observation, discretization of the convective flux terms of the Euler equation is based on a hybrid flux-vector splitting, known as the advection upstream splitting method (AUSM) scheme which combines the accuracy of flux-difference splitting and the robustness of flux-vector splitting. The AUSM scheme is based on the third-order compact scheme to the approximate finite difference equation was completely analyzed consequently. In one-dimensional problem for the first order schemes, an explicit method is adopted by using time integration method. In addition to that, development and modification of source code for the one-dimensional flow is validated with four test cases namely, unsteady shock tube, quasi-one-dimensional supersonic-subsonic nozzle flow, receding flow and shock waves in shock tubes. From these results, it was also carried out to ensure that the definition of Riemann problem can be identified. Further analysis had also been done in comparing the characteristic of AUSM scheme against experimental results, obtained from previous works and also comparative analysis with computational results generated by van Leer, KFVS and AUSMPW schemes. Furthermore, there is a remarkable improvement with the extension of the AUSM scheme from first-order to third-order accuracy in terms of shocks, contact discontinuities and rarefaction waves.

Psychometric Properties of the Perceived Wellness Culture and Environment Support Scale.

PubMed

Melnyk, Bernadette Mazurek; Szalacha, Laura A; Amaya, Megan

2018-05-01

This study reports on the psychometric properties of the 11-item Perceived Wellness Culture and Environment Support Scale (PWCESS) and its relationship with employee healthy lifestyle beliefs and behaviors. Faculty and staff (N = 3959) at a large public university in the United States mid-west completed the PWCESS along with healthy lifestyle beliefs and behaviors scales. Data were randomly split into 2 halves to explore the PWCESS' validity and reliability and the second half to confirm findings. Principal components analysis indicated a unidimensional construct. The PWCESS was positively related to healthy lifestyle beliefs and behaviors supporting the scale's validity. Confirmatory factor analysis supported the unidimensional construct (Cronbach's α = .92). Strong evidence supports the validity and reliability of the PWCESS. Future use of this scale could guide workplace intervention strategies to improve organizational wellness culture and employee health outcomes.

Creation of diffraction-limited non-Airy multifocal arrays using a spatially shifted vortex beam

NASA Astrophysics Data System (ADS)

Lin, Han; Gu, Min

2013-02-01

Diffraction-limited non-Airy multifocal arrays are created by focusing a phase-modulated vortex beam through a high numerical-aperture objective. The modulated phase at the back aperture of the objective resulting from the superposition of two concentric phase-modulated vortex beams allows for the generation of a multifocal array of cylindrically polarized non-Airy patterns. Furthermore, we shift the spatial positions of the phase vortices to manipulate the intensity distribution at each focal spot, leading to the creation of a multifocal array of split-ring patterns. Our method is experimentally validated by generating the predicted phase modulation through a spatial light modulator. Consequently, the spatially shifted circularly polarized vortex beam adopted in a dynamic laser direct writing system facilitates the fabrication of a split-ring microstructure array in a polymer material by a single exposure of a femtosecond laser beam.

Investigation of upwind, multigrid, multiblock numerical schemes for three dimensional flows. Volume 1: Runge-Kutta methods for a thin layer Navier-Stokes solver

NASA Technical Reports Server (NTRS)

Cannizzaro, Frank E.; Ash, Robert L.

1992-01-01

A state-of-the-art computer code has been developed that incorporates a modified Runge-Kutta time integration scheme, upwind numerical techniques, multigrid acceleration, and multi-block capabilities (RUMM). A three-dimensional thin-layer formulation of the Navier-Stokes equations is employed. For turbulent flow cases, the Baldwin-Lomax algebraic turbulence model is used. Two different upwind techniques are available: van Leer's flux-vector splitting and Roe's flux-difference splitting. Full approximation multi-grid plus implicit residual and corrector smoothing were implemented to enhance the rate of convergence. Multi-block capabilities were developed to provide geometric flexibility. This feature allows the developed computer code to accommodate any grid topology or grid configuration with multiple topologies. The results shown in this dissertation were chosen to validate the computer code and display its geometric flexibility, which is provided by the multi-block structure.

A compact spectrum splitting concentrator for high concentration photovoltaics based on the dispersion of a lens

NASA Astrophysics Data System (ADS)

He, J.; Flowers, C. A.; Yao, Y.; Atwater, H. A.; Rockett, A. A.; Nuzzo, R. G.

2018-06-01

Photovoltaic devices used in conjunction with functional optical elements for light concentration and spectrum splitting are known to be a viable approach for highly efficient photovoltaics. Conventional designs employ discrete optical elements, each with the task of either performing optical concentration or separating the solar spectrum. In the present work, we examine the performance of a compact photovoltaic architecture in which a single lens plays a dual role as both a concentrator and a spectrum splitter, the latter made possible by exploiting its intrinsic dispersion. A four-terminal two-junction InGaP/GaAs device is prepared to validate the concept and illustrates pathways for improvements. A spectral separation in the visible range is demonstrated at the focal point of a plano-convex lens with a geometric concentration ratio of 1104X with respect to the InGaP subcell.

A NEW THREE-DIMENSIONAL SOLAR WIND MODEL IN SPHERICAL COORDINATES WITH A SIX-COMPONENT GRID

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

Feng, Xueshang; Zhang, Man; Zhou, Yufen, E-mail: fengx@spaceweather.ac.cn

In this paper, we introduce a new three-dimensional magnetohydrodynamics numerical model to simulate the steady state ambient solar wind from the solar surface to 215 R {sub s} or beyond, and the model adopts a splitting finite-volume scheme based on a six-component grid system in spherical coordinates. By splitting the magnetohydrodynamics equations into a fluid part and a magnetic part, a finite volume method can be used for the fluid part and a constrained-transport method able to maintain the divergence-free constraint on the magnetic field can be used for the magnetic induction part. This new second-order model in space andmore » time is validated when modeling the large-scale structure of the solar wind. The numerical results for Carrington rotation 2064 show its ability to produce structured solar wind in agreement with observations.« less

On the Origins of Vortex Shedding in Two-dimensional Incompressible Flows

PubMed Central

Boghosian, M. E.; Cassel, K. W.

2016-01-01

An exegesis of a novel mechanism leading to vortex splitting and subsequent shedding that is valid for two-dimensional incompressible, inviscid or viscous, and external or internal or wall-bounded flows, is detailed in this research. The mechanism, termed the Vortex-Shedding Mechanism (VSM), is simple and intuitive, requiring only two coincident conditions in the flow: (1) the existence of a location with zero momentum and (2) the presence of a net force having a positive divergence. Numerical solutions of several model problems illustrate causality of the VSM. Moreover, the VSM criteria is proved to be a necessary and sufficient condition for a vortex splitting event in any two-dimensional, incompressible flow. The VSM is shown to exist in several canonical problems including the external flow past a circular cylinder. Suppression of the von Kármán vortex street is demonstrated for Reynolds numbers of 100 and 400 by mitigating the VSM. PMID:27795617

On the Origins of Vortex Shedding in Two-dimensional Incompressible Flows.

PubMed

Boghosian, M E; Cassel, K W

2016-12-01

An exegesis of a novel mechanism leading to vortex splitting and subsequent shedding that is valid for two-dimensional incompressible, inviscid or viscous, and external or internal or wall-bounded flows, is detailed in this research. The mechanism, termed the Vortex-Shedding Mechanism (VSM), is simple and intuitive, requiring only two coincident conditions in the flow: (1) the existence of a location with zero momentum and (2) the presence of a net force having a positive divergence. Numerical solutions of several model problems illustrate causality of the VSM. Moreover, the VSM criteria is proved to be a necessary and sufficient condition for a vortex splitting event in any two-dimensional, incompressible flow. The VSM is shown to exist in several canonical problems including the external flow past a circular cylinder. Suppression of the von Kármán vortex street is demonstrated for Reynolds numbers of 100 and 400 by mitigating the VSM.

A genetic algorithm for dynamic inbound ordering and outbound dispatching problem with delivery time windows

NASA Astrophysics Data System (ADS)

Kim, Byung Soo; Lee, Woon-Seek; Koh, Shiegheun

2012-07-01

This article considers an inbound ordering and outbound dispatching problem for a single product in a third-party warehouse, where the demands are dynamic over a discrete and finite time horizon, and moreover, each demand has a time window in which it must be satisfied. Replenishing orders are shipped in containers and the freight cost is proportional to the number of containers used. The problem is classified into two cases, i.e. non-split demand case and split demand case, and a mathematical model for each case is presented. An in-depth analysis of the models shows that they are very complicated and difficult to find optimal solutions as the problem size becomes large. Therefore, genetic algorithm (GA) based heuristic approaches are designed to solve the problems in a reasonable time. To validate and evaluate the algorithms, finally, some computational experiments are conducted.

A new splitting scheme to the discrete Boltzmann equation for non-ideal gases on non-uniform meshes

NASA Astrophysics Data System (ADS)

Patel, Saumil; Lee, Taehun

2016-12-01

We present a novel numerical procedure for solving the discrete Boltzmann equations (DBE) on non-uniform meshes. Our scheme is based on the Strang splitting method where we seek to investigate two-phase flow applications. In this note, we investigate the onset of parasitic currents which arise in many computational two-phase algorithms. To the best of our knowledge, the results presented in this work show, for the first time, a spectral element discontinuous Galerkin (SEDG) discretization of a discrete Boltzmann equation which successfully eliminates parasitic currents on non-uniform meshes. With the hope that this technique can be used for applications in complex geometries, calculations are performed on non-uniform mesh distributions by using high-order (spectral), body-fitting quadrilateral elements. Validation and verification of our work is carried out by comparing results against the classical 2D Young-Laplace law problem for a static drop.

Split liver transplantation in adults.

PubMed

Hashimoto, Koji; Fujiki, Masato; Quintini, Cristiano; Aucejo, Federico N; Uso, Teresa Diago; Kelly, Dympna M; Eghtesad, Bijan; Fung, John J; Miller, Charles M

2016-09-07

Split liver transplantation (SLT), while widely accepted in pediatrics, remains underutilized in adults. Advancements in surgical techniques and donor-recipient matching, however, have allowed expansion of SLT from utilization of the right trisegment graft to now include use of the hemiliver graft as well. Despite less favorable outcomes in the early experience, better outcomes have been reported by experienced centers and have further validated the feasibility of SLT. Importantly, more than two decades of experience have identified key requirements for successful SLT in adults. When these requirements are met, SLT can achieve outcomes equivalent to those achieved with other types of liver transplantation for adults. However, substantial challenges, such as surgical techniques, logistics, and ethics, persist as ongoing barriers to further expansion of this highly complex procedure. This review outlines the current state of SLT in adults, focusing on donor and recipient selection based on physiology, surgical techniques, surgical outcomes, and ethical issues.

Complex-envelope alternating-direction-implicit FDTD method for simulating active photonic devices with semiconductor/solid-state media.

PubMed

Singh, Gurpreet; Ravi, Koustuban; Wang, Qian; Ho, Seng-Tiong

2012-06-15

A complex-envelope (CE) alternating-direction-implicit (ADI) finite-difference time-domain (FDTD) approach to treat light-matter interaction self-consistently with electromagnetic field evolution for efficient simulations of active photonic devices is presented for the first time (to our best knowledge). The active medium (AM) is modeled using an efficient multilevel system of carrier rate equations to yield the correct carrier distributions, suitable for modeling semiconductor/solid-state media accurately. To include the AM in the CE-ADI-FDTD method, a first-order differential system involving CE fields in the AM is first set up. The system matrix that includes AM parameters is then split into two time-dependent submatrices that are then used in an efficient ADI splitting formula. The proposed CE-ADI-FDTD approach with AM takes 22% of the time as the approach of the corresponding explicit FDTD, as validated by semiconductor microdisk laser simulations.

Validation of Improved Broadband Shortwave and Longwave Fluxes Derived From GOES

NASA Technical Reports Server (NTRS)

Khaiyer, Mandana M.; Nordeen, Michele L.; Palikonda, Rabindra; Yi, Yuhong; Minnis, Patrick; Doelling, David R.

2009-01-01

Broadband (BB) shortwave (SW) and longwave (LW) fluxes at TOA (Top of Atmosphere) are crucial parameters in the study of climate and can be monitored over large portions of the Earth's surface using satellites. The VISST (Visible Infrared Solar Split-Window Technique) satellite retrieval algorithm facilitates derivation of these parameters from the Geostationery Operational Environmental Satellites (GOES). However, only narrowband (NB) fluxes are available from GOES, so this derivation requires use of narrowband-to-broadband (NB-BB) conversion coefficients. The accuracy of these coefficients affects the validity of the derived broadband (BB) fluxes. Most recently, NB-BB fits were re-derived using the NB fluxes from VISST/GOES data with BB fluxes observed by the CERES (Clouds and the Earth's Radiant Energy Budget) instrument aboard Terra, a sun-synchronous polar-orbiting satellite that crosses the equator at 10:30 LT. Subsequent comparison with ARM's (Atmospheric Radiation Measurement) BBHRP (Broadband Heating Rate Profile) BB fluxes revealed that while the derived broadband fluxes agreed well with CERES near the Terra overpass times, the accuracy of both LW and SW fluxes decreased farther away from the overpass times. Terra's orbit hampers the ability of the NB-BB fits to capture diurnal variability. To account for this in the LW, seasonal NB-BB fits are derived separately for day and night. Information from hourly SW BB fluxes from the Meteosat-8 Geostationary Earth Radiation Budget (GERB) is employed to include samples over the complete solar zenith angle (SZA) range sampled by Terra. The BB fluxes derived from these improved NB-BB fits are compared to BB fluxes computed with a radiative transfer model.

Two-dimensional Topology of the Sloan Digital Sky Survey

NASA Astrophysics Data System (ADS)

Hoyle, Fiona; Vogeley, Michael S.; Gott, J. Richard, III; Blanton, Michael; Tegmark, Max; Weinberg, David H.; Bahcall, N.; Brinkmann, J.; York, D.

2002-12-01

We present the topology of a volume-limited sample of 11,884 galaxies, selected from an apparent magnitude limited sample of over 100,000 galaxies observed as part of the Sloan Digital Sky Survey (SDSS). The data currently cover three main regions on the sky: one in the Galactic north and one in the south, both at zero degrees declination, and one area in the north at higher declination. Each of these areas covers a wide range of survey longitude but a narrow range of survey latitude, allowing the two-dimensional genus to be measured. The genus curves of the SDSS subsamples are similar, after appropriately normalizing these measurements for the different areas. We sum the genus curves from the three areas to obtain the total genus curve of the SDSS. The total curve has a shape similar to the genus curve derived from mock catalogs drawn from the Hubble volume ΛCDM simulation and is similar to that of a Gaussian random field. Likewise, comparison with the genus of the Two-Degree Field Galaxy Redshift Survey, after normalization for the difference in area, reveals remarkable similarity in the topology of these samples. We test for the effects of galaxy-type segregation by splitting the SDSS data into thirds, based on the u*-r* colors of the galaxies, and measure the genus of the reddest and bluest subsamples. This red/blue split in u*-r* is essentially a split by morphology, as explained by Strateva and coworkers. We find that the genus curve for the reddest galaxies exhibits a ``meatball'' shift of the topology-reflecting the concentration of red galaxies in high-density regions-compared to the bluest galaxies and the full sample, in agreement with predictions from simulations.

Low light adaptation: energy transfer processes in different types of light harvesting complexes from Rhodopseudomonas palustris.

PubMed

Moulisová, Vladimíra; Luer, Larry; Hoseinkhani, Sajjad; Brotosudarmo, Tatas H P; Collins, Aaron M; Lanzani, Guglielmo; Blankenship, Robert E; Cogdell, Richard J

2009-12-02

Energy transfer processes in photosynthetic light harvesting 2 (LH2) complexes isolated from purple bacterium Rhodopseudomonas palustris grown at different light intensities were studied by ground state and transient absorption spectroscopy. The decomposition of ground state absorption spectra shows contributions from B800 and B850 bacteriochlorophyll (BChl) a rings, the latter component splitting into a low energy and a high energy band in samples grown under low light (LL) conditions. A spectral analysis reveals strong inhomogeneity of the B850 excitons in the LL samples that is well reproduced by an exponential-type distribution. Transient spectra show a bleach of both the low energy and high energy bands, together with the respective blue-shifted exciton-to-biexciton transitions. The different spectral evolutions were analyzed by a global fitting procedure. Energy transfer from B800 to B850 occurs in a mono-exponential process and the rate of this process is only slightly reduced in LL compared to high light samples. In LL samples, spectral relaxation of the B850 exciton follows strongly nonexponential kinetics that can be described by a reduction of the bleach of the high energy excitonic component and a red-shift of the low energetic one. We explain these spectral changes by picosecond exciton relaxation caused by a small coupling parameter of the excitonic splitting of the BChl a molecules to the surrounding bath. The splitting of exciton energy into two excitonic bands in LL complex is most probably caused by heterogenous composition of LH2 apoproteins that gives some of the BChls in the B850 ring B820-like site energies, and causes a disorder in LH2 structure.

Factor Structure of the Revised TOEIC[R] Test: A Multiple-Sample Analysis

ERIC Educational Resources Information Center

In'nami, Yo; Koizumi, Rie

2012-01-01

This study examined the factor structure of the listening and reading sections of the revised Test of English for International Communication (TOEIC[R]) test. The data from the TOEIC IP (institutional program) test taken by 569 English learners were randomly split into two samples (n = 285 vs. 284). Four models (higher-order, correlated,…

Computerized Adaptive Testing Provides Reliable and Efficient Depression Measurement Using the CES-D Scale

PubMed Central

2017-01-01

Background The Center for Epidemiologic Studies Depression Scale (CES-D) is a measure of depressive symptomatology which is widely used internationally. Though previous attempts were made to shorten the CES-D scale, few have attempted to develop a Computerized Adaptive Test (CAT) version for the CES-D. Objective The aim of this study was to provide evidence on the efficiency and accuracy of the CES-D when administered using CAT using an American sample group. Methods We obtained a sample of 2060 responses to the CESD-D from US participants using the myPersonality application. The average age of participants was 26 years (range 19-77). We randomly split the sample into two groups to evaluate and validate the psychometric models. We used evaluation group data (n=1018) to assess dimensionality with both confirmatory factor and Mokken analysis. We conducted further psychometric assessments using item response theory (IRT), including assessments of item and scale fit to Samejima’s graded response model (GRM), local dependency and differential item functioning. We subsequently conducted two CAT simulations to evaluate the CES-D CAT using the validation group (n=1042). Results Initial CFA results indicated a poor fit to the model and Mokken analysis revealed 3 items which did not conform to the same dimension as the rest of the items. We removed the 3 items and fit the remaining 17 items to GRM. We found no evidence of differential item functioning (DIF) between age and gender groups. Estimates of the level of CES-D trait score provided by the simulated CAT algorithm and the original CES-D trait score derived from original scale were correlated highly. The second CAT simulation conducted using real participant data demonstrated higher precision at the higher levels of depression spectrum. Conclusions Depression assessments using the CES-D CAT can be more accurate and efficient than those made using the fixed-length assessment. PMID:28931496

Probabilistic mapping of descriptive health status responses onto health state utilities using Bayesian networks: an empirical analysis converting SF-12 into EQ-5D utility index in a national US sample.

PubMed

Le, Quang A; Doctor, Jason N

2011-05-01

As quality-adjusted life years have become the standard metric in health economic evaluations, mapping health-profile or disease-specific measures onto preference-based measures to obtain quality-adjusted life years has become a solution when health utilities are not directly available. However, current mapping methods are limited due to their predictive validity, reliability, and/or other methodological issues. We employ probability theory together with a graphical model, called a Bayesian network, to convert health-profile measures into preference-based measures and to compare the results to those estimated with current mapping methods. A sample of 19,678 adults who completed both the 12-item Short Form Health Survey (SF-12v2) and EuroQoL 5D (EQ-5D) questionnaires from the 2003 Medical Expenditure Panel Survey was split into training and validation sets. Bayesian networks were constructed to explore the probabilistic relationships between each EQ-5D domain and 12 items of the SF-12v2. The EQ-5D utility scores were estimated on the basis of the predicted probability of each response level of the 5 EQ-5D domains obtained from the Bayesian inference process using the following methods: Monte Carlo simulation, expected utility, and most-likely probability. Results were then compared with current mapping methods including multinomial logistic regression, ordinary least squares, and censored least absolute deviations. The Bayesian networks consistently outperformed other mapping models in the overall sample (mean absolute error=0.077, mean square error=0.013, and R overall=0.802), in different age groups, number of chronic conditions, and ranges of the EQ-5D index. Bayesian networks provide a new robust and natural approach to map health status responses into health utility measures for health economic evaluations.

Separation of ice crystals from interstitial aerosol particles using virtual impaction at the Fifth International Ice Nucleation Workshop FIN-3

NASA Astrophysics Data System (ADS)

Roesch, M.; Garimella, S.; Roesch, C.; Zawadowicz, M. A.; Katich, J. M.; Froyd, K. D.; Cziczo, D. J.

2016-12-01

In this study, a parallel-plate ice chamber, the SPectrometer for Ice Nuclei (SPIN, DMT Inc.) was combined with a pumped counterflow virtual impactor (PCVI, BMI Inc.) to separate ice crystals from interstitial aerosol particles by their aerodynamic size. These measurements were part of the FIN-3 workshop, which took place in fall 2015 at Storm Peak Laboratory (SPL), a high altitude mountain top facility (3220 m m.s.l.) in the Rocky Mountains. The investigated particles were sampled from ambient air and were exposed to cirrus-like conditions inside SPIN (-40°C, 130% RHice). Previous SPIN experiments under these conditions showed that ice crystals were found to be in the super-micron range. Connected to the outlet of the ice chamber, the PCVI was adjusted to separate all particulates aerodynamically larger than 3.5 micrometer to the sample flow while smaller ones were rejected and removed by a pump flow. Using this technique reduces the number of interstitial aerosol particles, which could bias subsequent ice nucleating particle (INP) analysis. Downstream of the PCVI, the separated ice crystals were evaporated and the flow with the remaining INPs was split up to a particle analysis by laser mass spectrometry (PALMS) instrument a laser aerosol spectrometer (LAS, TSI Inc.) and a single particle soot photometer (SP2, DMT Inc.). Based on the sample flow and the resolution of the measured particle data, the lowest concentration threshold for the SP2 instrument was 294 INP L-1 and for the LAS instrument 60 INP L-1. Applying these thresholds as filters to the measured PALMS time series 944 valid INP spectra using the SP2 threshold and 445 valid INP spectra using the LAS threshold were identified. A sensitivity study determining the number of good INP spectra as a function of the filter threshold concentration showed a two-phase linear growth when increasing the threshold concentration showing a breakpoint around 100 INP L-1.

Splitting a droplet for femtoliter liquid patterns and single cell isolation.

PubMed

Li, Huizeng; Yang, Qiang; Li, Guannan; Li, Mingzhu; Wang, Shutao; Song, Yanlin

2015-05-06

Well-defined microdroplet generation has attracted great interest, which is important for the high-resolution patterning and matrix distribution for chemical reactions and biological assays. By sliding a droplet on a patterned superhydrophilic/superhydrophobic substrate, tiny microdroplet arrays low to femtoliter were achieved with uniform volume and composition. Using this method, cells were successfully isolated, resulting in a single cell array. The droplet-splitting method is facile, sample-effective, and low-cost, which will be of great potential for the development of microdroplet arrays for biological analysis as well as patterning system and devices.

Evaluation of Fiber Reinforced Cement Using Digital Image Correlation

PubMed Central

Melenka, Garrett W.; Carey, Jason P.

2015-01-01

The effect of short fiber reinforcements on the mechanical properties of cement has been examined using a splitting tensile – digital image correlation (DIC) measurement method. Three short fiber reinforcement materials have been used in this study: fiberglass, nylon, and polypropylene. The method outlined provides a simple experimental setup that can be used to evaluate the ultimate tensile strength of brittle materials as well as measure the full field strain across the surface of the splitting tensile test cylindrical specimen. Since the DIC measurement technique is a contact free measurement this method can be used to assess sample failure. PMID:26039590

Priority compositions of boron carbide crystals obtained by self-propagating high-temperature synthesis

NASA Astrophysics Data System (ADS)

Ponomarev, V. I.; Konovalikhin, S. V.; Kovalev, I. D.; Vershinnikov, V. I.

2015-09-01

Splitting of reflections from boron carbide has been found for the first time by an X-ray diffraction study of polycrystalline mixture of boron carbide В15- х С х , (1.5 ≤ x ≤ 3) and its magnesium derivative C4B25Mg1.42. An analysis of reflection profiles shows that this splitting is due to the presence of boron carbide phases of different compositions in the sample, which are formed during crystal growth. The composition changes from В12.9С2.1 to В12.4С2.6.

Cross-validation pitfalls when selecting and assessing regression and classification models.

PubMed

Krstajic, Damjan; Buturovic, Ljubomir J; Leahy, David E; Thomas, Simon

2014-03-29

We address the problem of selecting and assessing classification and regression models using cross-validation. Current state-of-the-art methods can yield models with high variance, rendering them unsuitable for a number of practical applications including QSAR. In this paper we describe and evaluate best practices which improve reliability and increase confidence in selected models. A key operational component of the proposed methods is cloud computing which enables routine use of previously infeasible approaches. We describe in detail an algorithm for repeated grid-search V-fold cross-validation for parameter tuning in classification and regression, and we define a repeated nested cross-validation algorithm for model assessment. As regards variable selection and parameter tuning we define two algorithms (repeated grid-search cross-validation and double cross-validation), and provide arguments for using the repeated grid-search in the general case. We show results of our algorithms on seven QSAR datasets. The variation of the prediction performance, which is the result of choosing different splits of the dataset in V-fold cross-validation, needs to be taken into account when selecting and assessing classification and regression models. We demonstrate the importance of repeating cross-validation when selecting an optimal model, as well as the importance of repeating nested cross-validation when assessing a prediction error.

Comparing flood loss models of different complexity

NASA Astrophysics Data System (ADS)

Schröter, Kai; Kreibich, Heidi; Vogel, Kristin; Riggelsen, Carsten; Scherbaum, Frank; Merz, Bruno

2013-04-01

Any deliberation on flood risk requires the consideration of potential flood losses. In particular, reliable flood loss models are needed to evaluate cost-effectiveness of mitigation measures, to assess vulnerability, for comparative risk analysis and financial appraisal during and after floods. In recent years, considerable improvements have been made both concerning the data basis and the methodological approaches used for the development of flood loss models. Despite of that, flood loss models remain an important source of uncertainty. Likewise the temporal and spatial transferability of flood loss models is still limited. This contribution investigates the predictive capability of different flood loss models in a split sample cross regional validation approach. For this purpose, flood loss models of different complexity, i.e. based on different numbers of explaining variables, are learned from a set of damage records that was obtained from a survey after the Elbe flood in 2002. The validation of model predictions is carried out for different flood events in the Elbe and Danube river basins in 2002, 2005 and 2006 for which damage records are available from surveys after the flood events. The models investigated are a stage-damage model, the rule based model FLEMOps+r as well as novel model approaches which are derived using data mining techniques of regression trees and Bayesian networks. The Bayesian network approach to flood loss modelling provides attractive additional information concerning the probability distribution of both model predictions and explaining variables.

Exploring factors that influence students' attitudes toward midwifery in Jordan: Measuring psychometric properties of a newly developed tool.

PubMed

Al Hadid, Lourance A; Al-Rajabi, Omaymah; AlBarmawi, Marwa; Yousef Sayyah, Najah Sayyah; Toqan, Lwiza Moh'd

2018-03-01

Students' professional choice to proceed in midwifery is influenced by many factors. This study validated an instrument developed to assess students' attitudes toward midwifery in Jordan. It also addressed the motivating and de-motivating factors influencing students' decision concerning joining and continuing in midwifery. A descriptive, cross-section study was conducted on a convenience sample of 374 midwifery students representing private, governmental, and military midwifery colleges. The researchers developed the study questionnaire through conducting a comprehensive literature review, organizing common themes and consulting experts. Exploratory factor analysis and tests of normality and reliability, including Cronbach's Alpha and Bartlett's test, were used in the analysis. The result was three factors were explained by 23 items. They were as follows: professional knowledge, professional motivation factors, and de-motivating professional factors. The first 8 items explained nearly 61% of the variance. Cronbach's Alpha was 0.834 with a range of 0.835-0.839. The Spearman-Brown coefficient was 0.81 and Guttman Split-Half coefficient was 0.83. Issues of reliability and validity require a repetitive process of testing under a range of circumstances to ensure both stability and representation of the construct. However, addressing factors found to have impact of students' decisions is crucial to improve retention of high quality students. Copyright © 2018. Published by Elsevier Ltd.

Handling of uncertainty due to interference fringe in FT-NIR transmittance spectroscopy - Performance comparison of interference elimination techniques using glucose-water system

NASA Astrophysics Data System (ADS)

Beganović, Anel; Beć, Krzysztof B.; Henn, Raphael; Huck, Christian W.

2018-05-01

The applicability of two elimination techniques for interferences occurring in measurements with cells of short pathlength using Fourier transform near-infrared (FT-NIR) spectroscopy was evaluated. Due to the growing interest in the field of vibrational spectroscopy in aqueous biological fluids (e.g. glucose in blood), aqueous solutions of D-(+)-glucose were prepared and split into a calibration set and an independent validation set. All samples were measured with two FT-NIR spectrometers at various spectral resolutions. Moving average smoothing (MAS) and fast Fourier transform filter (FFT filter) were applied to the interference affected FT-NIR spectra in order to eliminate the interference pattern. After data pre-treatment, partial least squares regression (PLSR) models using different NIR regions were constructed using untreated (interference affected) spectra and spectra treated with MAS and FFT filter. The prediction of the independent validation set revealed information about the performance of the utilized interference elimination techniques, as well as the different NIR regions. The results showed that the combination band of water at approx. 5200 cm-1 is of great importance since its performance was superior to the one of the so-called first overtone of water at approx. 6800 cm-1. Furthermore, this work demonstrated that MAS and FFT filter are fast and easy-to-use techniques for the elimination of interference fringes in FT-NIR transmittance spectroscopy.

Development of a single-frequency bioimpedance prediction equation for fat-free mass in an adult Indigenous Australian population.

PubMed

Hughes, J T; Maple-Brown, L J; Piers, L S; Meerkin, J; O'Dea, K; Ward, L C

2015-01-01

To describe the development of a single-frequency bioimpedance prediction equation for fat-free mass (FFM) suitable for adult Aboriginal and Torres Strait Islander peoples with and without diabetes or indicators of chronic kidney disease (CKD). FFM was measured by whole-body dual-energy X-ray absorptiometry in 147 adult Indigenous Australians. Height, weight, body circumference and resistance were also measured. Adults with and without diabetes and indicators of CKD were examined. A random split sample with internal cross-validation approach was used to predict and subsequently validate FFM using resistance, height, weight, age and gender against measured FFM. Among 147 adults with a median body mass index of 31 kg/m(2), the final model of FFM was FFM (kg)=0.432 (height, cm(2)/resistance, ohm)-0.086 (age, years)+0.269 (weight, kg)-6.422 (if female)+16.429. Adjusted R(2) was 0.94 and the root mean square error was 3.33 kg. The concordance was high (rc=0.97) between measured and predicted FFM across a wide range of FFM (31-85 kg). In the context of the high burden of diabetes and CKD among adult Indigenous Australians, this new equation for FFM was both accurate and precise and based on easily acquired variables (height, weight, age, gender and resistance) among a heterogeneous adult cohort.

THE FERTILITY MOTIVATIONS OF YOUTH PREDICT LATER FERTILITY OUTCOMES: A PROSPECTIVE ANALYSIS OF NLSY DATA*

PubMed Central

Miller, Warren B.; Rodgers, Joseph Lee; Pasta, David J.

2010-01-01

We examine how the motivational sequence that leads to childbearing predicts fertility outcomes across reproductive careers. Using a motivational traits-desires-intentions theoretical framework, we test a structural equation model using prospective male and female data from the National Longitudinal Survey of Youth. Specifically, we take motivational data collected during the 1979–1982 period, when the youths were in their teens and early twenties, to predict the timing of the next child born after 1982 and the total number of children born by 2002. Separate models were estimated for males and females but with equality constraints imposed unless relaxing these constraints improved the overall model fit. The results indicate substantial explanatory power of fertility motivations for both short-term and long-term fertility outcomes. They also reveal the effects of both gender role attitude and educational intentions on these outcomes. Although some sex differences in model pathways occurred, the primary hypothesized pathways were essentially the same across the sexes. Two validity substudies support the soundness of the results. A third substudy comparing the male and female models across the sample split on the basis of previous childbearing revealed a number of pattern differences within the four sex-by-previous childbearing groups. Several of the more robust of these pattern differences offer interesting insights and support the validity and usefulness of our theoretical framework. PMID:20463915

Convolutional neural network approach for enhanced capture of breast parenchymal complexity patterns associated with breast cancer risk

NASA Astrophysics Data System (ADS)

Oustimov, Andrew; Gastounioti, Aimilia; Hsieh, Meng-Kang; Pantalone, Lauren; Conant, Emily F.; Kontos, Despina

2017-03-01

We assess the feasibility of a parenchymal texture feature fusion approach, utilizing a convolutional neural network (ConvNet) architecture, to benefit breast cancer risk assessment. Hypothesizing that by capturing sparse, subtle interactions between localized motifs present in two-dimensional texture feature maps derived from mammographic images, a multitude of texture feature descriptors can be optimally reduced to five meta-features capable of serving as a basis on which a linear classifier, such as logistic regression, can efficiently assess breast cancer risk. We combine this methodology with our previously validated lattice-based strategy for parenchymal texture analysis and we evaluate the feasibility of this approach in a case-control study with 424 digital mammograms. In a randomized split-sample setting, we optimize our framework in training/validation sets (N=300) and evaluate its descriminatory performance in an independent test set (N=124). The discriminatory capacity is assessed in terms of the the area under the curve (AUC) of the receiver operator characteristic (ROC). The resulting meta-features exhibited strong classification capability in the test dataset (AUC = 0.90), outperforming conventional, non-fused, texture analysis which previously resulted in an AUC=0.85 on the same case-control dataset. Our results suggest that informative interactions between localized motifs exist and can be extracted and summarized via a fairly simple ConvNet architecture.

Control of complex components with Smart Flexible Phased Arrays.

PubMed

Casula, O; Poidevin, C; Cattiaux, G; Dumas, Ph

2006-12-22

The inspection is mainly performed in contact with ultrasonic wedge transducers; However, the shape cannot fit the changing geometries of components (butt weld, nozzle, elbow). The variable thickness of the coupling layer, between the wedge and the local surface, leads to beam distortions and losses of sensitivity. Previous studies have shown that these two phenomena contribute to reduce the inspection performances leading to shadow area, split beam.... Flexible phased arrays have been developed to fit the complex profile and improve such controls. The radiating surface is composed with independent piezoelectric elements mechanically assembled and a profilometer, embedded in the transducer, measures the local distortion. The computed shape is used by an algorithm to compute in real-time the adapted delay laws compensating the distortions of 2D or 3D profiles. Those delay laws are transferred to the real-time UT acquisition system, which applies them to the piezoelectric elements. This self-adaptive process preserves, during the scanning, the features of the focused beam (orientation and focal depth) in the specimen. To validate the concept of the Smart Flexible Phased Array Transducer, prototypes have been integrated to detect flaws machined in mock-ups with realistic irregular 2D and 3D shapes. Inspections have been carried out on samples showing the enhancement performances of the "Smart Flexible Phased Array" and validating the mechanical and acoustical behaviors of these probes.

Identifying walking trips from GPS and accelerometer data in adolescent females

PubMed Central

Rodriguez, Daniel; Cho, GH; Elder, John; Conway, Terry; Evenson, Kelly R; Ghosh-Dastidar, Bonnie; Shay, Elizabeth; Cohen, Deborah A; Veblen-Mortenson, Sarah; Pickrell, Julie; Lytle, Leslie

2013-01-01

Background Studies that have combined accelerometers and global positioning systems (GPS) to identify walking have done so in carefully controlled conditions. This study tested algorithms for identifying walking trips from accelerometer and GPS data in free-living conditions. The study also assessed the accuracy of the locations where walking occurred compared to what participants reported in a diary. Methods A convenience sample of high school females was recruited (N=42) in 2007. Participants wore a GPS unit and an accelerometer, and recorded their out-of-school travel for six days. Split-sample validation was used to examine agreement in the daily and total number of walking trips with Kappa statistics and count regression models, while agreement in locations visited by walking was examined with geographic information systems. Results Agreement varied based on the parameters of the algorithm, with algorithms exhibiting moderate to substantial agreement with self-reported daily (Kappa = 0.33–0.48) and weekly (Kappa = 0.41–0.64) walking trips. Comparison of reported locations reached by walking and GPS data suggest that reported locations are accurate. Conclusions The use of GPS and accelerometers is promising for assessing the number of walking trips and the walking locations of adolescent females. PMID:21934163

Modeling and simulation of the deposition/relaxation processes of polycrystalline diatomic structures of metallic nitride films

NASA Astrophysics Data System (ADS)

García, M. F.; Restrepo-Parra, E.; Riaño-Rojas, J. C.

2015-05-01

This work develops a model that mimics the growth of diatomic, polycrystalline thin films by artificially splitting the growth into deposition and relaxation processes including two stages: (1) a grain-based stochastic method (grains orientation randomly chosen) is considered and by means of the Kinetic Monte Carlo method employing a non-standard version, known as Constant Time Stepping, the deposition is simulated. The adsorption of adatoms is accepted or rejected depending on the neighborhood conditions; furthermore, the desorption process is not included in the simulation and (2) the Monte Carlo method combined with the metropolis algorithm is used to simulate the diffusion. The model was developed by accounting for parameters that determine the morphology of the film, such as the growth temperature, the interacting atomic species, the binding energy and the material crystal structure. The modeled samples exhibited an FCC structure with grain formation with orientations in the family planes of < 111 >, < 200 > and < 220 >. The grain size and film roughness were analyzed. By construction, the grain size decreased, and the roughness increased, as the growth temperature increased. Although, during the growth process of real materials, the deposition and relaxation occurs simultaneously, this method may perhaps be valid to build realistic polycrystalline samples.

Robust frequency diversity based algorithm for clutter noise reduction of ultrasonic signals using multiple sub-spectrum phase coherence

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

Gongzhang, R.; Xiao, B.; Lardner, T.

2014-02-18

This paper presents a robust frequency diversity based algorithm for clutter reduction in ultrasonic A-scan waveforms. The performance of conventional spectral-temporal techniques like Split Spectrum Processing (SSP) is highly dependent on the parameter selection, especially when the signal to noise ratio (SNR) is low. Although spatial beamforming offers noise reduction with less sensitivity to parameter variation, phased array techniques are not always available. The proposed algorithm first selects an ascending series of frequency bands. A signal is reconstructed for each selected band in which a defect is present when all frequency components are in uniform sign. Combining all reconstructed signalsmore » through averaging gives a probability profile of potential defect position. To facilitate data collection and validate the proposed algorithm, Full Matrix Capture is applied on the austenitic steel and high nickel alloy (HNA) samples with 5MHz transducer arrays. When processing A-scan signals with unrefined parameters, the proposed algorithm enhances SNR by 20dB for both samples and consequently, defects are more visible in B-scan images created from the large amount of A-scan traces. Importantly, the proposed algorithm is considered robust, while SSP is shown to fail on the austenitic steel data and achieves less SNR enhancement on the HNA data.« less

Laser Induced Breakdown Spectroscopy Based on Single Beam Splitting and Geometric Configuration for Effective Signal Enhancement

PubMed Central

Yang, Guang; Lin, Qingyu; Ding, Yu; Tian, Di; Duan, Yixiang

2015-01-01

A new laser induced breakdown spectroscopy (LIBS) based on single-beam-splitting (SBS) and proper optical geometric configuration has been initially explored in this work for effective signal enhancement. In order to improve the interaction efficiency of laser energy with the ablated material, a laser beam operated in pulse mode was divided into two streams to ablate/excite the target sample in different directions instead of the conventional one beam excitation in single pulse LIBS (SP-LIBS). In spatial configuration, the laser beam geometry plays an important role in the emission signal enhancement. Thus, an adjustable geometric configuration with variable incident angle between the two splitted laser beams was constructed for achieving maximum signal enhancement. With the optimized angles of 60° and 70° for Al and Cu atomic emission lines at 396.15 nm and 324.75 nm respectively, about 5.6- and 4.8-folds signal enhancements were achieved for aluminum alloy and copper alloy samples compared to SP-LIBS. Furthermore, the temporal analysis, in which the intensity of atomic lines in SP-LIBS decayed at least ten times faster than the SBS-LIBS, proved that the energy coupling efficiency of SBS-LIBS was significantly higher than that of SP-LIBS. PMID:25557721

Toward a General Approach for RNA-Templated Hierarchical Assembly of Split-Proteins

PubMed Central

Furman, Jennifer L.; Badran, Ahmed H.; Ajulo, Oluyomi; Porter, Jason R.; Stains, Cliff I.; Segal, David J.; Ghosh, Indraneel

2010-01-01

The ability to conditionally turn on a signal or induce a function in the presence of a user-defined RNA target has potential applications in medicine and synthetic biology. Although sequence-specific pumilio repeat proteins can target a limited set of ssRNA sequences, there are no general methods for targeting ssRNA with designed proteins. As a first step toward RNA recognition, we utilized the RNA binding domain of argonaute, implicated in RNA interference, for specifically targeting generic 2-nucleotide, 3' overhangs of any dsRNA. We tested the reassembly of a split-luciferase enzyme guided by argonaute-mediated recognition of newly generated nucleotide overhangs when ssRNA is targeted by a designed complementary guide sequence. This approach was successful when argonaute was utilized in conjunction with a pumilio repeat and expanded the scope of potential ssRNA targets. However, targeting any desired ssRNA remained elusive as two argonaute domains provided minimal reassembled split-luciferase. We next designed and tested a second hierarchical assembly, wherein ssDNA guides are appended to DNA hairpins that serve as a scaffold for high affinity zinc fingers attached to split-luciferase. In the presence of a ssRNA target containing adjacent sequences complementary to the guides, the hairpins are brought into proximity, allowing for zinc finger binding and concomitant reassembly of the fragmented luciferase. The scope of this new approach was validated by specifically targeting RNA encoding VEGF, hDM2, and HER2. These approaches provide potentially general design paradigms for the conditional reassembly of fragmented proteins in the presence of any desired ssRNA target. PMID:20681585

Spin wave modes in out-of-plane magnetized nanorings

NASA Astrophysics Data System (ADS)

Zhou, X.; Tartakovskaya, E. V.; Kakazei, G. N.; Adeyeye, A. O.

2017-07-01

We investigated the spin wave modes in flat circular permalloy rings with a canted external bias field using ferromagnetic resonance spectroscopy. The external magnetic field H was large enough to saturate the samples. For θ =0∘ (perpendicular geometry), three distinct resonance peaks were observed experimentally. In the case of the cylindrical symmetry violation due to H inclination from normal to the ring plane (the angle θ of H inclination was varied in the 0∘-6∘ range), the splitting of all initial peaks appeared. The distance between neighbor split peaks increased with the θ increment. Unexpectedly, the biggest splitting was observed for the mode with the smallest radial wave vector. This special feature of splitting behavior is determined by the topology of the ring shape. Developed analytical theory revealed that in perpendicular geometry, each observed peak is a combination of signals from the set of radially quantized spin wave excitation with almost the same radial wave vectors, radial profiles, and frequencies, but with different azimuthal dependencies. This degeneracy is a consequence of circular symmetry of the system and can be removed by H inclination from the normal. Our findings were further supported by micromagnetic simulations.

Geochemical analysis of soils and sediments, Coeur d'Alene drainage basin, Idaho: sampling, analytical methods, and results

USGS Publications Warehouse

Box, Stephen E.; Bookstrom, Arthur A.; Ikramuddin, Mohammed; Lindsay, James

2001-01-01

(Fe), manganese (Mn), arsenic (As), and cadmium (Cd). In general inter-laboratory correlations are better for samples within the compositional range of the Standard Reference Materials (SRMs) from the National Institute of Standards and Technology (NIST). Analyses by EWU are the most accurate relative to the NIST standards (mean recoveries within 1% for Pb, Fe, Mn, and As, 3% for Zn and 5% for Cd) and are the most precise (within 7% of the mean at the 95% confidence interval). USGS-EDXRF is similarly accurate for Pb and Zn. XRAL and ACZ are relatively accurate for Pb (within 5-8% of certified NIST values), but were considerably less accurate for the other 5 elements of concern (10-25% of NIST values). However, analyses of sample splits by more than one laboratory reveal that, for some elements, XRAL (Pb, Mn, Cd) and ACZ (Pb, Mn, Zn, Fe) analyses were comparable to EWU analyses of the same samples (when values are within the range of NIST SRMs). These results suggest that, for some elements, XRAL and ACZ dissolutions are more effective on the matrix of the CdA samples than on the matrix of the NIST samples (obtained from soils around Butte, Montana). Splits of CdA samples analyzed by CHEMEX were the least accurate, yielding values 10-25% less than those of EWU.

Estimating sleep parameters using nasal pressure signals applicable to continuous positive airway pressure devices.

PubMed

Park, Jong-Uk; Erdenebayar, Urtnasan; Joo, Eun-Yeon; Lee, Kyoung-Joung

2017-06-27

This paper proposes a method for classifying sleep-wakefulness and estimating sleep parameters using nasal pressure signals applicable to a continuous positive airway pressure (CPAP) device. In order to classify the sleep-wakefulness states of patients with sleep-disordered breathing (SDB), apnea-hypopnea and snoring events are first detected. Epochs detected as SDB are classified as sleep, and time-domain- and frequency-domain-based features are extracted from the epochs that are detected as normal breathing. Subsequently, sleep-wakefulness is classified using a support vector machine (SVM) classifier in the normal breathing epoch. Finally, four sleep parameters-sleep onset, wake after sleep onset, total sleep time and sleep efficiency-are estimated based on the classified sleep-wakefulness. In order to develop and test the algorithm, 110 patients diagnosed with SDB participated in this study. Ninety of the subjects underwent full-night polysomnography (PSG) and twenty underwent split-night PSG. The subjects were divided into 50 patients of a training set (full/split: 42/8), 30 of a validation set (full/split: 24/6) and 30 of a test set (full/split: 24/6). In the experiments conducted, sleep-wakefulness classification accuracy was found to be 83.2% in the test set, compared with the PSG scoring results of clinical experts. Furthermore, all four sleep parameters showed higher correlations than the results obtained via PSG (r  ⩾  0.84, p  <  0.05). In order to determine whether the proposed method is applicable to CPAP, sleep-wakefulness classification performances were evaluated for each CPAP in the split-night PSG data. The results indicate that the accuracy and sensitivity of sleep-wakefulness classification by CPAP variation shows no statistically significant difference (p  <  0.05). The contributions made in this study are applicable to the automatic classification of sleep-wakefulness states in CPAP devices and evaluation of the quality of sleep.

Antecedent thermal injury worsens split-thickness skin graft quality: A clinically relevant porcine model of full-thickness burn, excision and grafting.

PubMed

Carlsson, Anders H; Rose, Lloyd F; Fletcher, John L; Wu, Jesse C; Leung, Kai P; Chan, Rodney K

2017-02-01

Current standard of care for full-thickness burn is excision followed by autologous split-thickness skin graft placement. Skin grafts are also frequently used to cover surgical wounds not amenable to linear closure. While all grafts have potential to contract, clinical observation suggests that antecedent thermal injury worsens contraction and impairs functional and aesthetic outcomes. This study evaluates the impact of antecedent full-thickness burn on split-thickness skin graft scar outcomes and the potential mediating factors. Full-thickness contact burns (100°C, 30s) were created on the backs of anesthetized female Yorkshire Pigs. After seven days, burn eschar was tangentially excised and covered with 12/1000th inch (300μm) split-thickness skin graft. For comparison, unburned wounds were created by sharp excision to fat before graft application. From 7 to 120days post-grafting, planimetric measurements, digital imaging and biopsies for histology, immunohistochemistry and gene expression were obtained. At 120days post-grafting, the Observer Scar Assessment Scale, colorimetry, contour analysis and optical graft height assessments were performed. Twenty-nine porcine wounds were analyzed. All measured metrics of clinical skin quality were significantly worse (p<0.05) in burn injured wounds. Histological analysis supported objective clinical findings with marked scar-like collagen proliferation within the dermis, increased vascular density, and prolonged and increased cellular infiltration. Observed differences in contracture also correlated with earlier and more prominent myofibroblast differentiation as demonstrated by α-SMA staining. Antecedent thermal injury worsens split-thickness skin graft quality, likely by multiple mechanisms including burn-related inflammation, microscopically inadequate excision, and dysregulation of tissue remodeling. A valid, reliable, clinically relevant model of full-thickness burn, excision and skin replacement therapy has been demonstrated. Future research to enhance quality of skin replacement therapies should be directed toward modulation of inflammation and assessments for complete excision. Copyright © 2016 Elsevier Ltd and ISBI. All rights reserved.

A System Approach to Navy Medical Education and Training. Appendix 18. Radiation Technician.

DTIC Science & Technology

1974-08-31

attrition was forecast to approximate twenty percent, final sample and sub-sample sizes were adjusted accordingly. Stratified random sampling... HYPERTENSIVE INTRAVENOUS PYELOGRAMS 2 ITAKE RENAL LOOPOGRAMI I 3 ITAKE CIXU, I.Eo CONSTANT INFUSION 4 10 RENAL SPLIT FUNCTION TEST, E.G. STAMEY 5...ITAKE PORTAL FILM OF AREA BEING TREATED WITH COBALT 32 [INFORM DOCTOR OF UNEXPECTED X-RAY FINDINGS 33 IREAD X-RAY FILMS FOR TECHNICAL ADEQUACY 34

Knowledge evolution in physics research: An analysis of bibliographic coupling networks

PubMed Central

Nanetti, Andrea; Cheong, Siew Ann

2017-01-01

Even as we advance the frontiers of physics knowledge, our understanding of how this knowledge evolves remains at the descriptive levels of Popper and Kuhn. Using the American Physical Society (APS) publications data sets, we ask in this paper how new knowledge is built upon old knowledge. We do so by constructing year-to-year bibliographic coupling networks, and identify in them validated communities that represent different research fields. We then visualize their evolutionary relationships in the form of alluvial diagrams, and show how they remain intact through APS journal splits. Quantitatively, we see that most fields undergo weak Popperian mixing, and it is rare for a field to remain isolated/undergo strong mixing. The sizes of fields obey a simple linear growth with recombination. We can also reliably predict the merging between two fields, but not for the considerably more complex splitting. Finally, we report a case study of two fields that underwent repeated merging and splitting around 1995, and how these Kuhnian events are correlated with breakthroughs on Bose-Einstein condensation (BEC), quantum teleportation, and slow light. This impact showed up quantitatively in the citations of the BEC field as a larger proportion of references from during and shortly after these events. PMID:28922427

Center Frequency Stabilization in Planar Dual-Mode Resonators during Mode-Splitting Control

NASA Astrophysics Data System (ADS)

Naji, Adham; Soliman, Mina H.

2017-03-01

Shape symmetry in dual-mode planar electromagnetic resonators results in their ability to host two degenerate resonant modes. As the designer enforces a controllable break in the symmetry, the degeneracy is removed and the two modes couple, exchanging energy and elevating the resonator into its desirable second-order resonance operation. The amount of coupling is controlled by the degree of asymmetry introduced. However, this mode coupling (or splitting) usually comes at a price. The centre frequency of the perturbed resonator is inadvertently drifted from its original value prior to coupling. Maintaining centre frequency stability during mode splitting is a nontrivial geometric design problem. In this paper, we analyse the problem and propose a novel method to compensate for this frequency drift, based on field analysis and perturbation theory, and we validate the solution through a practical design example and measurements. The analytical method used works accurately within the perturbational limit. It may also be used as a starting point for further numerical optimization algorithms, reducing the required computational time during design, when larger perturbations are made to the resonator. In addition to enabling the novel design example presented, it is hoped that the findings will inspire akin designs for other resonator shapes, in different disciplines and applications.

Investigating crater lake warming using ASTER thermal imagery: Case studies at Ruapehu, Poás, Kawah Ijen, and Copahué Volcanoes

NASA Astrophysics Data System (ADS)

Trunk, Laura; Bernard, Alain

2008-12-01

A two-channel or split-window algorithm designed to correct for atmospheric conditions was applied to thermal images taken by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) of Lake Yugama on Kusatsu-Shirane volcano in Japan in order to measure the temperature of its crater lake. These temperature calculations were validated using lake water temperatures that were collected on the ground. Overall, the agreement between the temperatures calculated using the split-window method and ground truth is quite good, typically ± 1.5 °C for cloud-free images. Data from fieldwork undertaken in the summer of 2004 at Kusatsu-Shirane allow a comparison of ground-truth data with the radiant temperatures measured using ASTER imagery. Further images were analyzed of Ruapehu, Poás, Kawah Ijen, and Copahué volcanoes to acquire time-series of lake temperatures. A total of 64 images of these 4 volcanoes covering a wide range of geographical locations and climates were analyzed. Results of the split-window algorithm applied to ASTER images are reliable for monitoring thermal changes in active volcanic lakes. These temperature data, when considered in conjunction with traditional volcano monitoring techniques, lead to a better understanding of whether and how thermal changes in crater lakes aid in eruption forecasting.

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

none,

Oak Ridge Associated Universities (ORAU), under the Oak Ridge Institute for Science and Education (ORISE) contract, collected split surface water samples with Nuclear Fuel Services (NFS) representatives on March 20, 2013. Representatives from the U.S. Nuclear Regulatory Commission and the Tennessee Department of Environment and Conservation were also in attendance. Samples were collected at four surface water stations, as required in the approved Request for Technical Assistance number 11-018. These stations included Nolichucky River upstream (NRU), Nolichucky River downstream (NRD), Martin Creek upstream (MCU), and Martin Creek downstream (MCD). Both ORAU and NFS performed gross alpha and gross beta analyses,more » and Table 1 presents the comparison of results using the duplicate error ratio (DER), also known as the normalized absolute difference. A DER {<=} 3 indicates that at a 99% confidence interval, split sample results do not differ significantly when compared to their respective one standard deviation (sigma) uncertainty (ANSI N42.22). The NFS split sample report does not specify the confidence level of reported uncertainties (NFS 2013). Therefore, standard two sigma reporting is assumed and uncertainty values were divided by 1.96. In conclusion, most DER values were less than 3 and results are consistent with low (e.g., background) concentrations. The gross beta result for sample 5198W0012 was the exception. The ORAU result of 9.23 ± 0.73 pCi/L from location MCD is well above NFS's result of -0.567 ± 0.63 pCi/L (non-detected). NFS's data package included a detected result for U-233/234, but no other uranium or plutonium detection, and nothing that would suggest the presence of beta-emitting radionuclides. The ORAU laboratory reanalyzed sample 5198W0012 using the remaining portion of the sample volume and a result of 11.3 ± 1.1 pCi/L was determined. As directed, the laboratory also counted the filtrate using gamma spectrometry analysis and identified only naturally occurring or ubiquitous man-made constituents, including beta emitters that are presumably responsible for the elevated gross beta values.« less

Lowermost mantle anisotropy near the eastern edge of the Pacific LLSVP: constraints from SKS-SKKS splitting intensity measurements

NASA Astrophysics Data System (ADS)

Deng, Jie; Long, Maureen D.; Creasy, Neala; Wagner, Lara; Beck, Susan; Zandt, George; Tavera, Hernando; Minaya, Estela

2017-08-01

Seismic anisotropy has been documented in many portions of the lowermost mantle, with particularly strong anisotropy thought to be present along the edges of large low shear velocity provinces (LLSVPs). The region surrounding the Pacific LLSVP, however, has not yet been studied extensively in terms of its anisotropic structure. In this study, we use seismic data from southern Peru, northern Bolivia and Easter Island to probe lowermost mantle anisotropy beneath the eastern Pacific Ocean, mostly relying on data from the Peru Lithosphere and Slab Experiment and Central Andean Uplift and Geodynamics of High Topography experiments. Differential shear wave splitting measurements from phases that have similar ray paths in the upper mantle but different ray paths in the lowermost mantle, such as SKS and SKKS, are used to constrain anisotropy in D″. We measured splitting for 215 same station-event SKS-SKKS pairs that sample the eastern Pacific LLSVP at the base of the mantle. We used measurements of splitting intensity(SI), a measure of the amount of energy on the transverse component, to objectively and quantitatively analyse any discrepancies between SKS and SKKS phases. While the overall splitting signal is dominated by the upper-mantle anisotropy, a minority of SKS-SKKS pairs (∼10 per cent) exhibit strongly discrepant splitting between the phases (i.e. the waveforms require a difference in SI of at least 0.4), indicating a likely contribution from lowermost mantle anisotropy. In order to enhance lower mantle signals, we also stacked waveforms within individual subregions and applied a waveform differencing technique to isolate the signal from the lowermost mantle. Our stacking procedure yields evidence for substantial splitting due to lowermost mantle anisotropy only for a specific region that likely straddles the edge of Pacific LLSVP. Our observations are consistent with the localization of deformation and anisotropy near the eastern boundary of the Pacific LLSVP, similar to previous observations for the African LLSVP.

Psychometric Properties of Difficulties of Working with Patients with Personality Disorders and Attitudes Towards Patients with Personality Disorders Scales.

PubMed

Eren, Nurhan

2014-12-01

In this study, we aimed to develop two reliable and valid assessment instruments for investigating the level of difficulties mental health workers experience while working with patients with personality disorders and the attitudes they develop tt the patients. The research was carried out based on the general screening model. The study sample consisted of 332 mental health workers in several mental health clinics of Turkey, with a certain amount of experience in working with personality disorders, who were selected with a random assignment method. In order to collect data, the Personal Information Questionnaire, Difficulty of Working with Personality Disorders Scale (PD-DWS), and Attitudes Towards Patients with Personality Disorders Scale (PD-APS), which are being examined for reliability and validity, were applied. To determine construct validity, the Adjective Check List, Maslach Burnout Inventory, and State and Trait Anxiety Inventory were used. Explanatory factor analysis was used for investigating the structural validity, and Cronbach alpha, Spearman-Brown, Guttman Split-Half reliability analyses were utilized to examine the reliability. Also, item reliability and validity computations were carried out by investigating the corrected item-total correlations and discriminative indexes of the items in the scales. For the PD-DWS KMO test, the value was .946; also, a significant difference was found for the Bartlett sphericity test (p<.001). The computed test-retest coefficient reliability was .702; the Cronbach alpha value of the total test score was .952. For PD-APS KMO, the value was .925; a significant difference was found in Bartlett sphericity test (p<.001); the computed reliability coefficient based on continuity was .806; and the Cronbach alpha value of the total test score was .913. Analyses on both scales were based on total scores. It was found that PD-DWS and PD-APS have good psychometric properties, measuring the structure that is being investigated, are compatible with other scales, have high levels of internal reliability between their items, and are consistent across time. Therefore, it was concluded that both scales are valid and reliable instruments.

A modified split Hopkinson pressure bar for toughness tests

NASA Astrophysics Data System (ADS)

Granier, N.; Grunenwald, T.

2006-08-01

In order to characterize material toughness or to study crack arrest under dynamic loading conditions, a new testing device has been developed at CEA/Valduc. A new Split Hopkinson Pressure Bar (SHPB) has been modified: it is now composed of a single incident bar and a double transmitter bar. With this facility, a notched specimen can be loaded under three points bending conditions. Qualification tests with titanium and steel notched samples are presented. Data treatment software has been adapted to estimate the sample deflection as a function of time and treat the energy balance. These results are compared with classical Charpy experiments. Effect of various contact areas between specimen and bars are studied to point out their influence on obtained measurements. The advantage of a “knife” contact compared to a plane one is then clearly demonstrated. All results obtained with this new testing device are in good agreement and show a reduced scattering.

Unexpected series of regular frequency spacing of δ Scuti stars in the non-asymptotic regime - I. The methodology

DOE PAGES

Paparo, M.; Benko, J. M.; Hareter, M.; ...

2016-05-11

In this study, a sequence search method was developed to search the regular frequency spacing in δ Scuti stars through visual inspection and an algorithmic search. We searched for sequences of quasi-equally spaced frequencies, containing at least four members per sequence, in 90 δ Scuti stars observed by CoRoT. We found an unexpectedly large number of independent series of regular frequency spacing in 77 δ Scuti stars (from one to eight sequences) in the non-asymptotic regime. We introduce the sequence search method presenting the sequences and echelle diagram of CoRoT 102675756 and the structure of the algorithmic search. Four sequencesmore » (echelle ridges) were found in the 5–21 d –1 region where the pairs of the sequences are shifted (between 0.5 and 0.59 d –1) by twice the value of the estimated rotational splitting frequency (0.269 d –1). The general conclusions for the whole sample are also presented in this paper. The statistics of the spacings derived by the sequence search method, by FT (Fourier transform of the frequencies), and the statistics of the shifts are also compared. In many stars more than one almost equally valid spacing appeared. The model frequencies of FG Vir and their rotationally split components were used to formulate the possible explanation that one spacing is the large separation while the other is the sum of the large separation and the rotational frequency. In CoRoT 102675756, the two spacings (2.249 and 1.977 d –1) are in better agreement with the sum of a possible 1.710 d –1 large separation and two or one times, respectively, the value of the rotational frequency.« less

Unexpected series of regular frequency spacing of δ Scuti stars in the non-asymptotic regime - I. The methodology

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

Paparo, M.; Benko, J. M.; Hareter, M.

In this study, a sequence search method was developed to search the regular frequency spacing in δ Scuti stars through visual inspection and an algorithmic search. We searched for sequences of quasi-equally spaced frequencies, containing at least four members per sequence, in 90 δ Scuti stars observed by CoRoT. We found an unexpectedly large number of independent series of regular frequency spacing in 77 δ Scuti stars (from one to eight sequences) in the non-asymptotic regime. We introduce the sequence search method presenting the sequences and echelle diagram of CoRoT 102675756 and the structure of the algorithmic search. Four sequencesmore » (echelle ridges) were found in the 5–21 d –1 region where the pairs of the sequences are shifted (between 0.5 and 0.59 d –1) by twice the value of the estimated rotational splitting frequency (0.269 d –1). The general conclusions for the whole sample are also presented in this paper. The statistics of the spacings derived by the sequence search method, by FT (Fourier transform of the frequencies), and the statistics of the shifts are also compared. In many stars more than one almost equally valid spacing appeared. The model frequencies of FG Vir and their rotationally split components were used to formulate the possible explanation that one spacing is the large separation while the other is the sum of the large separation and the rotational frequency. In CoRoT 102675756, the two spacings (2.249 and 1.977 d –1) are in better agreement with the sum of a possible 1.710 d –1 large separation and two or one times, respectively, the value of the rotational frequency.« less

Assessing the reliability of the short form 12 (SF-12) health survey in adults with mental health conditions: a report from the wellness incentive and navigation (WIN) study.

PubMed

Huo, Tianyao; Guo, Yi; Shenkman, Elizabeth; Muller, Keith

2018-02-13

Although Short Form (SF)-12 × 2® has been extensively studied and used as a valid measure of health-related quality of life in a variety of population groups, no systematic studies have described the reliability of the measure in patients with behavioral conditions or serious mental illness (SMI). We assessed the internal consistency, split-half reliability and annual test-retest correlations in a sample of 1587 participants with either a combination of physical and behavioral conditions or SMI. The Mosier's alpha was 0.70 for the Physical Composite Scale (PCS) and 0.69 for the Mental Health Composite Scale (MCS), indicating good internal consistency. We observed strong correlations between physical functioning, physical role and body pain scales (r = 0.55-0.56), and between social functioning, emotional role, and mental health (r = 0.53-0.58). We calculated split-half reliabilities to be 0.74 for physical functioning, 0.75 for physical role, 0.73 for emotional role and 0.65 for mental health respectively. We assessed the annual test-retest correlation using intraclass correlation (ICC) and found an ICC of 0.61 for PCS and 0.57 for MCS composite scores, adjusting for age, sex, race/ethnicity, and CRG. We found no decline in the correlations between baseline and the following study years until year 3. Our results encourage using SF-12v2® to assess health-related quality of life in the Medicaid population with combined physical and behavioral conditions or similar cohorts. The WIN study was registered with clinicaltrials.gov on April 22, 2015. NCT02440906 . Retrospectively registered.

Age estimation in the living: Transition analysis on developing third molars.

PubMed

Tangmose, Sara; Thevissen, Patrick; Lynnerup, Niels; Willems, Guy; Boldsen, Jesper

2015-12-01

A radiographic assessment of third molar development is essential for differentiating between juveniles and adolescents in forensic age estimations. As the developmental stages of third molars are highly correlated, age estimates based on a combination of a full set of third molar scores are statistically complicated. Transition analysis (TA) is a statistical method developed for estimating age at death in skeletons, which combines several correlated developmental traits into one age estimate including a 95% prediction interval. The aim of this study was to evaluate the performance of TA in the living on a full set of third molar scores. A cross sectional sample of 854 panoramic radiographs, homogenously distributed by sex and age (15.0-24.0 years), were randomly split in two; a reference sample for obtaining age estimates including a 95% prediction interval according to TA; and a validation sample to test the age estimates against actual age. The mean inaccuracy of the age estimates was 1.82 years (±1.35) in males and 1.81 years (±1.44) in females. The mean bias was 0.55 years (±2.20) in males and 0.31 years (±2.30) in females. Of the actual ages, 93.7% of the males and 95.9% of the females (validation sample) fell within the 95% prediction interval. Moreover, at a sensitivity and specificity of 0.824 and 0.937 in males and 0.814 and 0.827 in females, TA performs well in differentiating between being a minor as opposed to an adult. Although accuracy does not outperform other methods, TA provides unbiased age estimates which minimize the risk of wrongly estimating minors as adults. Furthermore, when corrected ad hoc, TA produces appropriate prediction intervals. As TA allows expansion with additional traits, i.e. stages of development of the left hand-wrist and the clavicle, it has a great potential for future more accurate and reproducible age estimates, including an estimated probability of having attained the legal age limit of 18 years. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Characterization of the spatial variability of soil available zinc at various sampling densities using grouped soil type information.

PubMed

Song, Xiao-Dong; Zhang, Gan-Lin; Liu, Feng; Li, De-Cheng; Zhao, Yu-Guo

2016-11-01

The influence of anthropogenic activities and natural processes involved high uncertainties to the spatial variation modeling of soil available zinc (AZn) in plain river network regions. Four datasets with different sampling densities were split over the Qiaocheng district of Bozhou City, China. The difference of AZn concentrations regarding soil types was analyzed by the principal component analysis (PCA). Since the stationarity was not indicated and effective ranges of four datasets were larger than the sampling extent (about 400 m), two investigation tools, namely F3 test and stationarity index (SI), were employed to test the local non-stationarity. Geographically weighted regression (GWR) technique was performed to describe the spatial heterogeneity of AZn concentrations under the non-stationarity assumption. GWR based on grouped soil type information (GWRG for short) was proposed so as to benefit the local modeling of soil AZn within each soil-landscape unit. For reference, the multiple linear regression (MLR) model, a global regression technique, was also employed and incorporated the same predictors as in the GWR models. Validation results based on 100 times realization demonstrated that GWRG outperformed MLR and can produce similar or better accuracy than the GWR approach. Nevertheless, GWRG can generate better soil maps than GWR for limit soil data. Two-sample t test of produced soil maps also confirmed significantly different means. Variogram analysis of the model residuals exhibited weak spatial correlation, rejecting the use of hybrid kriging techniques. As a heuristically statistical method, the GWRG was beneficial in this study and potentially for other soil properties.

Validation of the German version of the 'Hypogonadism Related Symptom Scale' (HRS) in andrological patients with infertility, HIV infection and metabolic syndrome.

PubMed

Alidjanov, J; Wolf, J; Schuppe, H-C; Weidner, W; Diemer, T; Linn, T; Halefeldt, I; Wagenlehner, F; Wiltink, J; Pilatz, A

2014-12-01

As commonly used self-reported screening instruments for male hypogonadism demonstrated lack of specificity, a Hypogonadism Related Symptom Scale (HRS) was developed in 2009 as a novel self-rating screening tool. As the questionnaire has not been validated, the purpose of our study was to perform a validation in patients presenting with different disorders (e.g. infertility, HIV infection or metabolic syndrome) and disease-related risk to develop hypogonadism. Two hundred and eighteen patients aged 19-71 years (40.1 ± 9.5) who completed the HRS and other common questionnaires [International Index Of Erectile Function (IIEF), National Institutes of Health Chronic Prostatitis Symptom Index (NIH-CPSI), Hospital Anxiety and Depression Scale (HADS), short form (SF)-12] were included. In all patients, blood levels of total testosterone, luteinizing hormone, follicle-stimulating hormone, oestradiol and sex hormone-binding globulin were determined and free testosterone was calculated. Cronbach's α for the scale was 0.896, split-half 0.871 for the 1st half and 0.807 for the 2nd half. Spearman-Brown coefficient was 0.767, and Guttman split-half coefficient was 0.759. Consistent correlations were found between HRS and IIEF5 (ρ = 0.57, P < 0.001), and HADS (ρ = -0.6, P < 0.001). In addition, HRS was significantly correlated with total testosterone (ρ = 0.135, P < 0.05), free testosterone (ρ = 0.148, P < 0.05) and oestradiol (ρ = -0.134, P < 0.05). Our validation study confirms the data from the initial development of the HRS questionnaire. Clinicians might have an additional advantage from the HRS when investigating males with suspected hypogonadism. © 2014 Blackwell Verlag GmbH.

Verification of reliability and validity of a Japanese version of the Rathus Assertiveness Schedule.

PubMed

Suzuki, Eiko; Kanoya, Yuka; Katsuki, Takeshi; Sato, Chifumi

2007-07-01

To verify the reliability and validity of a Japanese version of the Rathus Assertiveness Schedule in novice nurses to contribute to nursing management. An adequate scale is needed to measure the assertiveness and the effect of assertion training for Japanese nurses and to compare them with those in other countries. Rathus Assertiveness Schedule was adapted to Japanese with back-translation and its validity was examined in 989 novice nurses. The Japanese version showed a high coefficient of reliability in a split-half reliability test (r=0.76; P<0.01). The coefficient of reliability of Cronbach's alpha was high (r=0.84; P<0.01) indicating high internal consistency. The similarity with the concept of stress coping was shown. We extracted eight principal factors using factor analysis with varimax rotation. Elements of these factors were similar to those of the original Rathus Assertiveness Schedule. The Japanese version of Rathus Assertiveness Schedule was verified.

A machine learning approach for classification of anatomical coverage in CT

NASA Astrophysics Data System (ADS)

Wang, Xiaoyong; Lo, Pechin; Ramakrishna, Bharath; Goldin, Johnathan; Brown, Matthew

2016-03-01

Automatic classification of anatomical coverage of medical images is critical for big data mining and as a pre-processing step to automatically trigger specific computer aided diagnosis systems. The traditional way to identify scans through DICOM headers has various limitations due to manual entry of series descriptions and non-standardized naming conventions. In this study, we present a machine learning approach where multiple binary classifiers were used to classify different anatomical coverages of CT scans. A one-vs-rest strategy was applied. For a given training set, a template scan was selected from the positive samples and all other scans were registered to it. Each registered scan was then evenly split into k × k × k non-overlapping blocks and for each block the mean intensity was computed. This resulted in a 1 × k3 feature vector for each scan. The feature vectors were then used to train a SVM based classifier. In this feasibility study, four classifiers were built to identify anatomic coverages of brain, chest, abdomen-pelvis, and chest-abdomen-pelvis CT scans. Each classifier was trained and tested using a set of 300 scans from different subjects, composed of 150 positive samples and 150 negative samples. Area under the ROC curve (AUC) of the testing set was measured to evaluate the performance in a two-fold cross validation setting. Our results showed good classification performance with an average AUC of 0.96.

Effects of Agitation and Storage Temperature on Measurements of Hydration Status.

PubMed

Adams, Heather M; Eberman, Lindsey E; Yeargin, Susan W; Niemann, Andrew J; Mata, Heather L; Dziedzicki, David J

2015-12-01

Hypohydration can have significant implications on normal physiological functions of the body. This study aimed to determine the impact of agitation, storage temperature, and storage time on urine osmolality compared to the criterion control. We used a descriptive diagnostic validity test design. To investigate agitation, we recruited 75 healthy individuals (males = 41, females = 34; mean age = 22 ± 5 years; mean self-reported height = 172 ± 23 cm and mass = 77 ± 17 kg) who provided one or more samples (total = 81). The independent variables were agitation (vortex, hand shaken, no agitation) and temperature (room temperature, freezer, and refrigerator) type. Participants completed informed consent, a health questionnaire and were asked to provide a urine sample, which was split and labeled according to agitation type or storage temperature. Urine osmolality was used to determine hydration status at two time points (within 2 hours [control], 48 hours). We used t-tests to determine the difference between each condition and the control and calculated percent error for each condition. No significant differences for no agitation (t79 = -0.079, P = 0.937), hand shaken (t79 = 1.395, P = 0.167) or vortex mixed (t79 = -0.753, P = 0.453) were identified when compared to the criterion control. No significant differences for room temperature (t82 = -0.720, P = 0.474), refrigerator (t82 = -2.697, P = 0.008) or freezer (t82 = 2.576, P = 0.012) were identified when compared to the criterion control. Our findings suggest agitation of urine specimen is not necessary and samples do not require refrigeration or freezing if assessed within 48 hours. Analysis within two hours of collection is not necessary and samples can be stored for up to 48 hours without impacting the hydration status of the sample.

Energetic band structure of Zn3P2 crystals

NASA Astrophysics Data System (ADS)

Stamov, I. G.; Syrbu, N. N.; Dorogan, A. V.

2013-01-01

Optical functions n, k, ε1, ε2 and d2ε2/dE2 have been determined from experimental reflection spectra in the region of 1-10 eV. The revealed electronic transitions are localized in the Brillouin zone. The magnitude of valence band splitting caused by the spin-orbital interaction ΔSO is lower than the splitting caused by the crystal field ΔCR in the center of Brillouin zone and L and X points. The switching effects are investigated in Zn3P2 crystals. The characteristics of experimental samples with electric switching, adjustable resistors, and time relays based on Zn3P2 are presented.

A Comparison of Aircraft Maintenance Organizational Structures

DTIC Science & Technology

1992-09-01

Outputs ... ...................... 85 Appendix E : Double Cross-Validation ........... 117 Appendix F: Exchange of Independent Variables...splits into three major production branches (6). See Figure 8. 26 Aircraf t Interm ia•’ e Maintenance Off icerzI A ssistantAIKO I 1|A/ant a A Traiing...responsible for all aircraft maintenance activities, see Figure 9 (4:3). rdor ! E •; e Techn•1i Se~rvices Wff oE r I f .1 Bass Airaraf t Iaintenanoc E

QSAR as a random event: modeling of nanoparticles uptake in PaCa2 cancer cells.

PubMed

Toropov, Andrey A; Toropova, Alla P; Puzyn, Tomasz; Benfenati, Emilio; Gini, Giuseppina; Leszczynska, Danuta; Leszczynski, Jerzy

2013-06-01

Quantitative structure-property/activity relationships (QSPRs/QSARs) are a tool to predict various endpoints for various substances. The "classic" QSPR/QSAR analysis is based on the representation of the molecular structure by the molecular graph. However, simplified molecular input-line entry system (SMILES) gradually becomes most popular representation of the molecular structure in the databases available on the Internet. Under such circumstances, the development of molecular descriptors calculated directly from SMILES becomes attractive alternative to "classic" descriptors. The CORAL software (http://www.insilico.eu/coral) is provider of SMILES-based optimal molecular descriptors which are aimed to correlate with various endpoints. We analyzed data set on nanoparticles uptake in PaCa2 pancreatic cancer cells. The data set includes 109 nanoparticles with the same core but different surface modifiers (small organic molecules). The concept of a QSAR as a random event is suggested in opposition to "classic" QSARs which are based on the only one distribution of available data into the training and the validation sets. In other words, five random splits into the "visible" training set and the "invisible" validation set were examined. The SMILES-based optimal descriptors (obtained by the Monte Carlo technique) for these splits are calculated with the CORAL software. The statistical quality of all these models is good. Copyright © 2013 Elsevier Ltd. All rights reserved.

Cross-domain and multi-task transfer learning of deep convolutional neural network for breast cancer diagnosis in digital breast tomosynthesis

NASA Astrophysics Data System (ADS)

Samala, Ravi K.; Chan, Heang-Ping; Hadjiiski, Lubomir; Helvie, Mark A.; Richter, Caleb; Cha, Kenny

2018-02-01

We propose a cross-domain, multi-task transfer learning framework to transfer knowledge learned from non-medical images by a deep convolutional neural network (DCNN) to medical image recognition task while improving the generalization by multi-task learning of auxiliary tasks. A first stage cross-domain transfer learning was initiated from ImageNet trained DCNN to mammography trained DCNN. 19,632 regions-of-interest (ROI) from 2,454 mass lesions were collected from two imaging modalities: digitized-screen film mammography (SFM) and full-field digital mammography (DM), and split into training and test sets. In the multi-task transfer learning, the DCNN learned the mass classification task simultaneously from the training set of SFM and DM. The best transfer network for mammography was selected from three transfer networks with different number of convolutional layers frozen. The performance of single-task and multitask transfer learning on an independent SFM test set in terms of the area under the receiver operating characteristic curve (AUC) was 0.78+/-0.02 and 0.82+/-0.02, respectively. In the second stage cross-domain transfer learning, a set of 12,680 ROIs from 317 mass lesions on DBT were split into validation and independent test sets. We first studied the data requirements for the first stage mammography trained DCNN by varying the mammography training data from 1% to 100% and evaluated its learning on the DBT validation set in inference mode. We found that the entire available mammography set provided the best generalization. The DBT validation set was then used to train only the last four fully connected layers, resulting in an AUC of 0.90+/-0.04 on the independent DBT test set.

Multichannel FPGA based MVT system for high precision time (20 ps RMS) and charge measurement

NASA Astrophysics Data System (ADS)

Pałka, M.; Strzempek, P.; Korcyl, G.; Bednarski, T.; Niedźwiecki, Sz.; Białas, P.; Czerwiński, E.; Dulski, K.; Gajos, A.; Głowacz, B.; Gorgol, M.; Jasińska, B.; Kamińska, D.; Kajetanowicz, M.; Kowalski, P.; Kozik, T.; Krzemień, W.; Kubicz, E.; Mohhamed, M.; Raczyński, L.; Rudy, Z.; Rundel, O.; Salabura, P.; Sharma, N. G.; Silarski, M.; Smyrski, J.; Strzelecki, A.; Wieczorek, A.; Wiślicki, W.; Zieliński, M.; Zgardzińska, B.; Moskal, P.

2017-08-01

In this article it is presented an FPGA based Multi-Voltage Threshold (MVT) system which allows of sampling fast signals (1-2 ns rising and falling edge) in both voltage and time domain. It is possible to achieve a precision of time measurement of 20 ps RMS and reconstruct charge of signals, using a simple approach, with deviation from real value smaller than 10%. Utilization of the differential inputs of an FPGA chip as comparators together with an implementation of a TDC inside an FPGA allowed us to achieve a compact multi-channel system characterized by low power consumption and low production costs. This paper describes realization and functioning of the system comprising 192-channel TDC board and a four mezzanine cards which split incoming signals and discriminate them. The boards have been used to validate a newly developed Time-of-Flight Positron Emission Tomography system based on plastic scintillators. The achieved full system time resolution of σ(TOF) ≈ 68 ps is by factor of two better with respect to the current TOF-PET systems.

The Persian developmental sentence scoring as a clinical measure of morphosyntax in children.

PubMed

Jalilevand, Nahid; Kamali, Mohammad; Modarresi, Yahya; Kazemi, Yalda

2016-01-01

Background: Developmental Sentence Scoring (DSS) was developed as a numerical measurement and a clinical method based on the morphosyntactic acquisition in the English language. The aim of this study was to develop a new numerical tool similar to DSS to assess the morphosyntactic abilities in Persian-speaking children. Methods: In this cross-sectional and comparative study, the language samples of 115 typically developing Persian-speaking children aged 30 - 65 months were audio recorded during the free play and picture description sessions. The Persian Developmental Sentence Score (PDSS) and the Mean Length of Utterance (MLU) were calculated. Pearson correlation and one - way Analysis of variance (ANOVA) were used for data analysis. Results: The correlation between PDSS and MLU in morphemes (convergent validity) was significant with a correlation coefficient of 0.97 (p< 0.001). The value Cronbach's Alpha (α= 0.79) in the grammatical categories and the split-half coefficient (0.86) indicated acceptable internal consistency reliability. Conclusion: The PDSS could be used as a reliable numerical measurement to estimate the syntactic development in Persian-speaking children.

The Persian developmental sentence scoring as a clinical measure of morphosyntax in children

PubMed Central

Jalilevand, Nahid; Kamali, Mohammad; Modarresi, Yahya; Kazemi, Yalda

2016-01-01

Background: Developmental Sentence Scoring (DSS) was developed as a numerical measurement and a clinical method based on the morphosyntactic acquisition in the English language. The aim of this study was to develop a new numerical tool similar to DSS to assess the morphosyntactic abilities in Persian-speaking children. Methods: In this cross-sectional and comparative study, the language samples of 115 typically developing Persian-speaking children aged 30 - 65 months were audio recorded during the free play and picture description sessions. The Persian Developmental Sentence Score (PDSS) and the Mean Length of Utterance (MLU) were calculated. Pearson correlation and one – way Analysis of variance (ANOVA) were used for data analysis. Results: The correlation between PDSS and MLU in morphemes (convergent validity) was significant with a correlation coefficient of 0.97 (p< 0.001). The value Cronbach's Alpha (α= 0.79) in the grammatical categories and the split-half coefficient (0.86) indicated acceptable internal consistency reliability. Conclusion: The PDSS could be used as a reliable numerical measurement to estimate the syntactic development in Persian-speaking children. PMID:28210600

Six centuries of May-July precipitation in Cyprus from tree rings

NASA Astrophysics Data System (ADS)

Touchan, Ramzi; Christou, Andreas K.; Meko, David M.

2014-12-01

A May-July precipitation nested reconstruction for the period AD 1415-2010 was developed from multi-century tree-ring records of Pinus nigra, Pinus brutia, and Cedrus brevifolia for Cyprus. Calibration and verification statistics for the period 1917-2010 show a good level of skill, and split-sample validation over 1917-2010 supports temporal stability of the tree-ring signal for precipitation. Smoothed annual time series of reconstructed precipitation and a tally of drought events in a moving time window indicate that the calibration period is not representative of the full range of drought variability. While convective precipitation in the warm season may be driven strongly by local factors, composite maps of geopotential height anomaly for dry years and wet years support large-scale atmospheric-flow influence related to height anomalies over the broader region of northeast Africa and the eastern Mediterranean. Emerging positive trend in reconstruction residuals may be an early sign of exacerbation of drought stress on trees by recent warming in May-July. Future warming expected from increases in greenhouse gases poses a threat to forest resources in Cyprus and elsewhere in the Mediterranean.

A Measure of Barriers Toward Medical Disclosure Among Health Professionals in the United Arab Emirates.

PubMed

Zaghloul, Ashraf Ahmad; Elsergany, Moetaz; Mosallam, Rasha

2018-03-01

There has been a growing awareness that patients are subject to injuries that can be prevented as a direct consequence of health care. Error disclosure is an effective technique to restore the lost trust with the health care system. The current study aimed to develop a valid and reliable scale to determine the factors facilitating the disclosure of health professionals in health organizations. This study had a cross-sectional design that consisted of 722 responses (response rate of 68.3%) from 1 private and 1 public hospital in Sharjah, United Arab Emirates. The data collection tool included 23 items rated on a Likert scale ranging from 5, strongly agree, to 1, strongly disagree.The internal consistency was established through calculating the split-half reliability for part 1 (12 items), which had a Cronbach coefficient of 0.65, and part 2 (11 items), which had a Cronbach coefficient of 0.62. Scale validity was assessed with the Kaiser-Meyer-Olkin measure of sampling adequacy, which had a value of 0.62, and the Bartlett test of sphericity (approximated χ = 13012.2, P = 0.0001) supported the factorability of the correlation matrix. The varimax rotation revealed 5 components that explained 77.8% of the total variance. The varimax rotation revealed 21 items loaded on the following 5 factors: fear of disclosure and provider image consequences (factor 1), apology (factor 2), organizational culture toward patient safety (factor 3), professional ethics and transparency (factor 4), as well as patient and provider education (factor 5). The disclosure of medical mistakes requires preliminary considerations to effectively and compassionately disclose these events to patients. The validity and reliability of the results support the use of this scale at hospitals as part of the health care providers' disclosure processes.

Long Noncoding RNAs AC009014.3 and Newly Discovered XPLAID Differentiate Aggressive and Indolent Prostate Cancers.

PubMed

Cesnik, Anthony J; Yang, Bing; Truong, Andrew; Etheridge, Tyler; Spiniello, Michele; Steinbrink, Maisie I; Shortreed, Michael R; Frey, Brian L; Jarrard, David F; Smith, Lloyd M

2018-06-01

The molecular mechanisms underlying aggressive versus indolent disease are not fully understood. Recent research has implicated a class of molecules known as long noncoding RNAs (lncRNAs) in tumorigenesis and progression of cancer. Our objective was to discover lncRNAs that differentiate aggressive and indolent prostate cancers. We analyzed paired tumor and normal tissues from six aggressive Gleason score (GS) 8-10 and six indolent GS 6 prostate cancers. Extracted RNA was split for poly(A)+ and ribosomal RNA depletion library preparations, followed byRNA sequencing (RNA-Seq) using an Illumina HiSeq 2000. We developed an RNA-Seq data analysis pipeline to discover and quantify these molecules. Candidate lncRNAs were validated using RT-qPCR on 87 tumor tissue samples: 28 (GS 6), 28 (GS 3+4), 6 (GS 4+3), and 25 (GS 8-10). Statistical correlations between lncRNAs and clinicopathologic variables were tested using ANOVA. The 43 differentially expressed (DE) lncRNAs between aggressive and indolent prostate cancers included 12 annotated and 31 novel lncRNAs. The top six DE lncRNAs were selected based on large, consistent fold-changes in the RNA-Seq results. Three of these candidates passed RT-qPCR validation, including AC009014.3 (P < .001 in tumor tissue) and a newly discovered X-linked lncRNA named XPLAID (P = .049 in tumor tissue and P = .048 in normal tissue). XPLAID and AC009014.3 show promise as prognostic biomarkers. We discovered several dozen lncRNAs that distinguish aggressive and indolent prostate cancers, of which four were validated using RT-qPCR. The investigation into their biology is ongoing. Published by Elsevier Inc.

Factor structure and criterion validity across the full scale and ten short forms of the CES-D among Chinese adolescents.

PubMed

Yang, Wenhui; Xiong, Ge; Garrido, Luis Eduardo; Zhang, John X; Wang, Meng-Cheng; Wang, Chong

2018-04-16

We systematically examined the factor structure and criterion validity across the full scale and 10 short forms of the Center for Epidemiological Studies Depression Scale (CES-D) with Chinese youth. Participants were 5,434 Chinese adolescents in Grades 7 to 12 who completed the full CES-D; 612 of them further completed a structured diagnostic interview with the major depressive disorder (MDD) module of the Kiddie Schedule for Affective Disorder and Schizophrenia for School-age Children. Using a split-sample approach, a series of 4-, 3-, 2-, and 1-factor models were tested using exploratory structural equation modeling and cross-validated using confirmatory factor analysis; the dimensionality was also evaluated by parallel analysis in conjunction with the scree test and aided by factor mixture analysis. The results indicated that a single-factor model of depression with a wording method factor fitted the data well, and was the optimal structure underlying the scores of the full and shortened CES-D. Additionally, receiver operating characteristic curve analyses for MDD case detection showed that the CES-D full-scale scores accurately detected MDD youth (area under the curve [AUC] = .84). Furthermore, the short-form scores produced comparable AUCs with the full scale (.82 to .85), as well as similar levels of sensitivity and specificity when using optimal cutoffs. These findings suggest that depression among Chinese adolescents can be adequately measured and screened for by a single-factor structure underlying the CES-D scores, and that the short forms provide a viable alternative to the full instrument. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Stromal mast cells in invasive breast cancer are a marker of favourable prognosis: a study of 4,444 cases.

PubMed

Rajput, Ashish B; Turbin, Dmitry A; Cheang, Maggie Cu; Voduc, David K; Leung, Sam; Gelmon, Karen A; Gilks, C Blake; Huntsman, David G

2008-01-01

We have previously demonstrated in a pilot study of 348 invasive breast cancers that mast cell (MC) infiltrates within primary breast cancers are associated with a good prognosis. Our aim was to verify this finding in a larger cohort of invasive breast cancer patients and examine the relationship between the presence of MCs and other clinical and pathological features. Clinically annotated tissue microarrays (TMAs) containing 4,444 cases were constructed and stained with c-Kit (CD-117) using standard immunoperoxidase techniques to identify and quantify MCs. For statistical analysis, we applied a split-sample validation technique. Breast cancer specific survival was analyzed by Kaplan-Meier [KM] method and log rank test was used to compare survival curves. Survival analysis by KM method showed that the presence of stromal MCs was a favourable prognostic factor in the training set (P = 0.001), and the validation set group (P = 0.006). X-tile plot generated to define the optimal number of MCs showed that the presence of any number of stromal MCs predicted good prognosis. Multivariate analysis showed that the MC effect in the training set (Hazard ratio [HR] = 0.804, 95% Confidence interval [CI], 0.653-0.991, P = 0.041) and validation set analysis (HR = 0.846, 95% CI, 0.683-1.049, P = 0.128) was independent of age, tumor grade, tumor size, lymph node, ER and Her2 status. This study concludes that stromal MC infiltration in invasive breast cancer is an independent good prognostic marker and reiterates the critical role of local inflammatory responses in breast cancer progression.

Stromal mast cells in invasive breast cancer are a marker of favourable prognosis: a study of 4,444 cases

PubMed Central

Rajput, Ashish B.; Turbin, Dmitry A.; Cheang, Maggie CU; Voduc, David K.; Leung, Sam; Gelmon, Karen A.; Gilks, C. Blake

2007-01-01

Purpose We have previously demonstrated in a pilot study of 348 invasive breast cancers that mast cell (MC) infiltrates within primary breast cancers are associated with a good prognosis. Our aim was to verify this finding in a larger cohort of invasive breast cancer patients and examine the relationship between the presence of MCs and other clinical and pathological features. Experimental design Clinically annotated tissue microarrays (TMAs) containing 4,444 cases were constructed and stained with c-Kit (CD-117) using standard immunoperoxidase techniques to identify and quantify MCs. For statistical analysis, we applied a split-sample validation technique. Breast cancer specific survival was analyzed by Kaplan–Meier [KM] method and log rank test was used to compare survival curves. Results Survival analysis by KM method showed that the presence of stromal MCs was a favourable prognostic factor in the training set (P = 0.001), and the validation set group (P = 0.006). X-tile plot generated to define the optimal number of MCs showed that the presence of any number of stromal MCs predicted good prognosis. Multivariate analysis showed that the MC effect in the training set (Hazard ratio [HR] = 0.804, 95% Confidence interval [CI], 0.653–0.991, P = 0.041) and validation set analysis (HR = 0.846, 95% CI, 0.683–1.049, P = 0.128) was independent of age, tumor grade, tumor size, lymph node, ER and Her2 status. Conclusions This study concludes that stromal MC infiltration in invasive breast cancer is an independent good prognostic marker and reiterates the critical role of local inflammatory responses in breast cancer progression. PMID:17431762

High quantum-yield phosphors via quantum splitting and upconversion

NASA Astrophysics Data System (ADS)

Jeong, Joayoung

The Gd3+ ion has been used to induce quantum splitting in luminescent materials by using cross-relaxation energy transfer (CRET). In Nd:LiGdF4, quantum splitting results from a two-step CRET between Gd3+ and Nd3+, first involving a transition 6G→6I on Gd3+ and an excitation within the 4f3 configuration of Nd3+ followed by a second CRET that brings Gd3+ to 6P7/2. The excited Nd3+ ion rapidly relaxes nonradiatively to the emitting 4F3/2. The excited Gd3+ ion then transfers its energy back to Nd3+, which gives rise to the second photon. The result is a quantum yield of 1.05 +/- 0.35 with emission in the NIR following excitation at 175 nm. GdF3:Pr3+, Eu 3+ also exhibits quantum splitting, but only at very low concentration of Pr3+ (0.3%) and Eu3+ (0.2%), resulting in a quantum yield of approximately 20% under 160-nm excitation. Host intrinsic emission via a self-trapped exciton (STE) was also examined as a means to sensitize Gd3+ emission. The material ScPO4:Gd 3+ exhibits a high absolute quantum yield of 0.9 +/- 0.2 under 170-nm excitation, demonstrating a potentially new and efficient pathway for exciting quantum splitting phosphors. Single crystals of the material GdZrF7 were grown, and its structure was established via single-crystal X-ray diffraction methods. Doped samples of GdZrF7:Yb3+, Er3+ exhibit bright up-conversion luminescence with light output that is up to twice that of a commercial material based on the host Gd2O2S. When doped with Eu3+, the fluoride also emits a nearly white color under vacuum ultraviolet excitation with an absolute quantum yield near 0.9. The new compound Gd4.67(SiO4)3S was synthesized and studied. The structure was established via single-crystal X-ray methods, and the luminescence of Tb3+ samples was investigated.

Validation of the Chinese version of functional assessment of anorexia-cachexia therapy (FAACT) scale for measuring quality of life in cancer patients with cachexia.

PubMed

Zhou, Ting; Yang, Kaixiang; Thapa, Sudip; Fu, Qiang; Jiang, Yongsheng; Yu, Shiying

2017-04-01

The assessment of quality of life (QOL) is an important part of cachexia management for cancer patients. Functional assessment of anorexia-cachexia therapy (FAACT), a specific QOL instrument for cachexia patients, has not been validated in Chinese population. The aim of this study was to validate the FAACT scale in Chinese cancer patients for its future use. Eligible cancer patients were included in our study. Patients' demographic and clinical characteristics were collected from the electronic medical records. Patients were asked to complete the Chinese version of FAACT scale and the MD Anderson symptom inventory (MDASI), and then the reliability and validity were analyzed. A total of 285 patients were enrolled in our study, data of 241 patients were evaluated. Coefficients of Cronbach's alpha, test-retest and split-half analyses were all greater than 0.8, which indicated an excellent reliability for FAACT scale. In item-subscale correlation analysis and factor analysis, good construct validity for FAACT scale was found. The correlation between FAACT and MDASI interference subscale showed reasonable criterion-related validity, and for further clinical validation, the FAACT scale showed excellent discriminative validity for distinguishing patients in different cachexia status and in different performance status. The Chinese version of FAACT scale has good reliability and validity and is suitable for measuring QOL of cachexia patients in Chinese population.

An Efficient Data Partitioning to Improve Classification Performance While Keeping Parameters Interpretable

PubMed Central

Korjus, Kristjan; Hebart, Martin N.; Vicente, Raul

2016-01-01

Supervised machine learning methods typically require splitting data into multiple chunks for training, validating, and finally testing classifiers. For finding the best parameters of a classifier, training and validation are usually carried out with cross-validation. This is followed by application of the classifier with optimized parameters to a separate test set for estimating the classifier’s generalization performance. With limited data, this separation of test data creates a difficult trade-off between having more statistical power in estimating generalization performance versus choosing better parameters and fitting a better model. We propose a novel approach that we term “Cross-validation and cross-testing” improving this trade-off by re-using test data without biasing classifier performance. The novel approach is validated using simulated data and electrophysiological recordings in humans and rodents. The results demonstrate that the approach has a higher probability of discovering significant results than the standard approach of cross-validation and testing, while maintaining the nominal alpha level. In contrast to nested cross-validation, which is maximally efficient in re-using data, the proposed approach additionally maintains the interpretability of individual parameters. Taken together, we suggest an addition to currently used machine learning approaches which may be particularly useful in cases where model weights do not require interpretation, but parameters do. PMID:27564393

An Efficient Data Partitioning to Improve Classification Performance While Keeping Parameters Interpretable.

PubMed

Korjus, Kristjan; Hebart, Martin N; Vicente, Raul

2016-01-01

Supervised machine learning methods typically require splitting data into multiple chunks for training, validating, and finally testing classifiers. For finding the best parameters of a classifier, training and validation are usually carried out with cross-validation. This is followed by application of the classifier with optimized parameters to a separate test set for estimating the classifier's generalization performance. With limited data, this separation of test data creates a difficult trade-off between having more statistical power in estimating generalization performance versus choosing better parameters and fitting a better model. We propose a novel approach that we term "Cross-validation and cross-testing" improving this trade-off by re-using test data without biasing classifier performance. The novel approach is validated using simulated data and electrophysiological recordings in humans and rodents. The results demonstrate that the approach has a higher probability of discovering significant results than the standard approach of cross-validation and testing, while maintaining the nominal alpha level. In contrast to nested cross-validation, which is maximally efficient in re-using data, the proposed approach additionally maintains the interpretability of individual parameters. Taken together, we suggest an addition to currently used machine learning approaches which may be particularly useful in cases where model weights do not require interpretation, but parameters do.

Psychological Flexibility of Nurses in a Cancer Hospital: Preliminary Validation of a Chinese Version of the Work-related Acceptance and Action Questionnaire.

PubMed

Xu, Xianghua; Liu, Xiangyu; Ou, Meijun; Xie, Chanjuan; Chen, Yongyi

2018-01-01

To translate the English work-related acceptance and action questionnaire (WAAQ), make cross-cultural adaptations, and examine its psychometric properties when used by Chinese oncology nurses. After translation, the psychometric properties of the Chinese WAAQ were analyzed among 417 nurses, and content validity was determined by six experts. Item-level content validity index (CVI) values were between 0.83 and 1.00; scale-level CVI/universal agreement (S-CVI/UA) and S-CVI/average were 0.86 and 0.98, respectively, which implicated a good content validity. The correlation of the Chinese WAAQ with AAQ-II ( r s = -0.247, P < 0.001) suggested criterion validity, and those with General Health Questionnaire-12 (-0.250, <0.001) and general self-efficacy scale (0.491, <0.001) and Utrecht work engagement scale (UWES) (0.439, <0.001) suggested convergent validity. Exploratory factor analysis identified a seven-item, one-factor structure of WAAQ. The Chinese version of WAAQ had high internal consistency (Cronbach's α = 0.920), with an item-total correlation coefficient of 0.702-0.828 ( P < 0.05), split-half reliability of 0.933, and test-retest reliability of 0.772. The Chinese WAAQ is a reliable and valid tool for assessing psychological flexibility in Chinese oncology nurses.

Liquid chromatography coupled to quadrupole-time of flight tandem mass spectrometry based quantitative structure-retention relationships of amino acid analogues derivatized via n-propyl chloroformate mediated reaction.

PubMed

Kritikos, Nikolaos; Tsantili-Kakoulidou, Anna; Loukas, Yannis L; Dotsikas, Yannis

2015-07-17

In the current study, quantitative structure-retention relationships (QSRR) were constructed based on data obtained by a LC-(ESI)-QTOF-MS/MS method for the determination of amino acid analogues, following their derivatization via chloroformate esters. Molecules were derivatized via n-propyl chloroformate/n-propanol mediated reaction. Derivatives were acquired through a liquid-liquid extraction procedure. Chromatographic separation is based on gradient elution using methanol/water mixtures from a 70/30% composition to an 85/15% final one, maintaining a constant rate of change. The group of examined molecules was diverse, including mainly α-amino acids, yet also β- and γ-amino acids, γ-amino acid analogues, decarboxylated and phosphorylated analogues and dipeptides. Projection to latent structures (PLS) method was selected for the formation of QSRRs, resulting in a total of three PLS models with high cross-validated coefficients of determination Q(2)Y. For this reason, molecular structures were previously described through the use of descriptors. Through stratified random sampling procedures, 57 compounds were split to a training set and a test set. Model creation was based on multiple criteria including principal component significance and eigenvalue, variable importance, form of residuals, etc. Validation was based on statistical metrics Rpred(2),QextF2(2),QextF3(2) for the test set and Roy's metrics rm(Av)(2) and rm(δ)(2), assessing both predictive stability and internal validity. Based on aforementioned models, simplified equivalent were then created using a multi-linear regression (MLR) method. MLR models were also validated with the same metrics. The suggested models are considered useful for the estimation of retention times of amino acid analogues for a series of applications. Copyright © 2015 Elsevier B.V. All rights reserved.

Multigene signature for predicting prognosis of patients with 1p19q co-deletion diffuse glioma.

PubMed

Hu, Xin; Martinez-Ledesma, Emmanuel; Zheng, Siyuan; Kim, Hoon; Barthel, Floris; Jiang, Tao; Hess, Kenneth R; Verhaak, Roel G W

2017-06-01

Co-deletion of 1p and 19q marks a diffuse glioma subtype associated with relatively favorable overall survival; however, heterogeneous clinical outcomes are observed within this category. We assembled gene expression profiles and sample annotation of 374 glioma patients carrying the 1p/19q co-deletion. We predicted 1p/19q status using gene expression when annotation was missing. A first cohort was randomly split into training (n = 170) and a validation dataset (n = 163). A second validation set consisted of 41 expression profiles. An elastic-net penalized Cox proportional hazards model was applied to build a classifier model through cross-validation within the training dataset. The selected 35-gene signature was used to identify high-risk and low-risk groups in the validation set, which showed significantly different overall survival (P = .00058, log-rank test). For time-to-death events, the high-risk group predicted by the gene signature yielded a hazard ratio of 1.78 (95% confidence interval, 1.02-3.11). The signature was also significantly associated with clinical outcome in the The Cancer Genome Atlas (CGA) IDH-mutant 1p/19q wild-type and IDH-wild-type glioma cohorts. Pathway analysis suggested that high risk was associated with increased acetylation activity and inflammatory response. Tumor purity was found to be significantly decreased in high-risk IDH-mutant with 1p/19q co-deletion gliomas and IDH-wild-type glioblastomas but not in IDH-wild-type lower grade or IDH-mutant, non-co-deleted gliomas. We identified a 35-gene signature that identifies high-risk and low-risk categories of 1p/19q positive glioma patients. We have demonstrated heterogeneity amongst a relatively new glioma subtype and provided a stepping stone towards risk stratification. © The Author(s) 2017. Published by Oxford University Press on behalf of the Society for Neuro-Oncology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Derivation and Validation of a Clostridium difficile Infection Recurrence Prediction Rule in a National Cohort of Veterans.

PubMed

Reveles, Kelly R; Mortensen, Eric M; Koeller, Jim M; Lawson, Kenneth A; Pugh, Mary Jo V; Rumbellow, Sarah A; Argamany, Jacqueline R; Frei, Christopher R

2018-03-01

Prior studies have identified risk factors for recurrent Clostridium difficile infection (CDI), but few studies have integrated these factors into a clinical prediction rule that can aid clinical decision-making. The objectives of this study were to derive and validate a CDI recurrence prediction rule to identify patients at risk for first recurrence in a national cohort of veterans. Retrospective cohort study. Veterans Affairs Informatics and Computing Infrastructure. A total of 22,615 adult Veterans Health Administration beneficiaries with first-episode CDI between October 1, 2002, and September 30, 2014; of these patients, 7538 were assigned to the derivation cohort and 15,077 to the validation cohort. A 60-day CDI recurrence prediction rule was created in a derivation cohort using backward logistic regression. Those variables significant at p<0.01 were assigned an integer score proportional to the regression coefficient. The model was then validated in the derivation cohort and a separate validation cohort. Patients were then split into three risk categories, and rates of recurrence were described for each category. The CDI recurrence prediction rule included the following predictor variables with their respective point values: prior third- and fourth-generation cephalosporins (1 point), prior proton pump inhibitors (1 point), prior antidiarrheals (1 point), nonsevere CDI (2 points), and community-onset CDI (3 points). In the derivation cohort, the 60-day CDI recurrence risk for each score ranged from 7.5% (0 points) to 57.9% (8 points). The risk score was strongly correlated with recurrence (R 2  = 0.94). Patients were split into low-risk (0-2 points), medium-risk (3-5 points), and high-risk (6-8 points) classes and had the following recurrence rates: 8.9%, 20.2%, and 35.0%, respectively. Findings were similar in the validation cohort. Several CDI and patient-specific factors were independently associated with 60-day CDI recurrence risk. When integrated into a clinical prediction rule, higher risk scores and risk classes were strongly correlated with CDI recurrence. This clinical prediction rule can be used by providers to identify patients at high risk for CDI recurrence and help guide preventive strategy decisions, while accounting for clinical judgment. © 2018 Pharmacotherapy Publications, Inc.