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Sample records for adaptive tests cat

  1. "catR": An R Package for Computerized Adaptive Testing

    ERIC Educational Resources Information Center

    Magis, David; Raiche, Gilles

    2011-01-01

    Computerized adaptive testing (CAT) is an active current research field in psychometrics and educational measurement. However, there is very little software available to handle such adaptive tasks. The R package "catR" was developed to perform adaptive testing with as much flexibility as possible, in an attempt to provide a developmental and…

  2. When Cognitive Diagnosis Meets Computerized Adaptive Testing: CD-CAT

    ERIC Educational Resources Information Center

    Cheng, Ying

    2009-01-01

    Computerized adaptive testing (CAT) is a mode of testing which enables more efficient and accurate recovery of one or more latent traits. Traditionally, CAT is built upon Item Response Theory (IRT) models that assume unidimensionality. However, the problem of how to build CAT upon latent class models (LCM) has not been investigated until recently,…

  3. Microcomputer Network for Computerized Adaptive Testing (CAT): Program Listing.

    ERIC Educational Resources Information Center

    Quan, Baldwin; And Others

    This program listing is a supplement to the Microcomputer Network for Computerized Adaptive Testing (CAT). The driver textfile program allows access to major subprograms of the CAT project. The test administration textfile program gives examinees a prescribed set of subtests. The parameter management textfile program establishes a file containing…

  4. SimulCAT: Windows Software for Simulating Computerized Adaptive Test Administration

    ERIC Educational Resources Information Center

    Han, Kyung T.

    2012-01-01

    Most, if not all, computerized adaptive testing (CAT) programs use simulation techniques to develop and evaluate CAT program administration and operations, but such simulation tools are rarely available to the public. Up to now, several software tools have been available to conduct CAT simulations for research purposes; however, these existing…

  5. A Web-Based Computerized Adaptive Testing (CAT) to Assess Patient Perception in Hospitalization

    PubMed Central

    Chien, Tsair-Wei; Wang, Wen-Chung; Huang, Sheng-Yun; Lai, Wen-Pin

    2011-01-01

    Background Many hospitals have adopted mobile nursing carts that can be easily rolled up to a patient’s bedside to access charts and help nurses perform their rounds. However, few papers have reported data regarding the use of wireless computers on wheels (COW) at patients’ bedsides to collect questionnaire-based information of their perception of hospitalization on discharge from the hospital. Objective The purpose of this study was to evaluate the relative efficiency of computerized adaptive testing (CAT) and the precision of CAT-based measures of perceptions of hospitalized patients, as compared with those of nonadaptive testing (NAT). An Excel module of our CAT multicategory assessment is provided as an example. Method A total of 200 patients who were discharged from the hospital responded to the CAT-based 18-item inpatient perception questionnaire on COW. The numbers of question administrated were recorded and the responses were calibrated using the Rasch model. They were compared with those from NAT to show the advantage of CAT over NAT. Results Patient measures derived from CAT and NAT were highly correlated (r = 0.98) and their measurement precisions were not statistically different (P = .14). CAT required fewer questions than NAT (an efficiency gain of 42%), suggesting a reduced burden for patients. There were no significant differences between groups in terms of gender and other demographic characteristics. Conclusions CAT-based administration of surveys of patient perception substantially reduced patient burden without compromising the precision of measuring patients’ perceptions of hospitalization. The Excel module of animation-CAT on the wireless COW that we developed is recommended for use in hospitals. PMID:21844001

  6. Microcomputer Network for Computerized Adaptive Testing (CAT): Program Listing. Supplement.

    DTIC Science & Technology

    1984-03-01

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  7. A Computer Adaptive Testing Version of the Addiction Severity Index-Multimedia Version (ASI-MV): The Addiction Severity CAT.

    PubMed

    Butler, Stephen F; Black, Ryan A; McCaffrey, Stacey A; Ainscough, Jessica; Doucette, Ann M

    2017-02-23

    The purpose of this study was to develop and validate a computer adaptive testing (CAT) version of the Addiction Severity Index-Multimedia Version (ASI-MV), the Addiction Severity CAT. This goal was accomplished in 4 steps. First, new candidate items for Addiction Severity CAT domains were evaluated after brainstorming sessions with experts in substance abuse treatment. Next, this new item bank was psychometrically evaluated on a large nonclinical (n = 4,419) and substance abuse treatment (n = 845) sample. Based on these results, final items were selected and calibrated for the creation of the Addiction Severity CAT algorithms. Once the algorithms were developed for the entire assessment, a fully functioning prototype of an Addiction Severity CAT was created. CAT simulations were conducted, and optimal termination criteria were selected for the Addiction Severity CAT algorithms. Finally, construct validity of the CAT algorithms was evaluated by examining convergent and discriminant validity and sensitivity to change. The Addiction Severity CAT was determined to be valid, sensitive to change, and reliable. Further, the Addiction Severity CAT's time of completion was found to be significantly less than the average time of completion for the ASI-MV composite scores. This study represents the initial validation of an Addiction Severity CAT based on item response theory, and further exploration of the Addiction Severity CAT is needed. (PsycINFO Database Record

  8. Evaluation of a computer-adaptive test for the assessment of depression (D-CAT) in clinical application.

    PubMed

    Fliege, Herbert; Becker, Janine; Walter, Otto B; Rose, Matthias; Bjorner, Jakob B; Klapp, Burghard F

    2009-01-01

    In the past, a German Computerized Adaptive Test, based on Item Response Theory (IRT), was developed for purposes of assessing the construct depression [Computer-adaptive test for depression (D-CAT)]. This study aims at testing the feasibility and validity of the real computer-adaptive application.The D-CAT, supplied by a bank of 64 items, was administered on personal digital assistants (PDAs) to 423 consecutive patients suffering from psychosomatic and other medical conditions (78 with depression). Items were adaptively administered until a predetermined reliability (r > or = 0.90) was attained. For validation purposes, the Hospital Anxiety and Depression Scale (HADS), the Centre for Epidemiological Studies Depression (CES-D) scale, and the Beck Depression Inventory (BDI) were administered. Another sample of 114 patients was evaluated using standardized diagnostic interviews [Composite International Diagnostic Interview (CIDI)].The D-CAT was quickly completed (mean 74 seconds), well accepted by the patients and reliable after an average administration of only six items. In 95% of the cases, 10 items or less were needed for a reliable score estimate. Correlations between the D-CAT and the HADS, CES-D, and BDI ranged between r = 0.68 and r = 0.77. The D-CAT distinguished between diagnostic groups as well as established questionnaires do.The D-CAT proved an efficient, well accepted and reliable tool. Discriminative power was comparable to other depression measures, whereby the CAT is shorter and more precise. Item usage raises questions of balancing the item selection for content in the future.

  9. Assessing CAT Test Security Severity

    ERIC Educational Resources Information Center

    Yi, Qing; Zhang, Jinming; Chang, Hua-Hua

    2006-01-01

    In addition to its precision superiority over nonadaptive tests, another known advantage of computerized adaptive tests (CATs) is that they can be offered on a continuous basis. This is advantageous to examinees in terms of flexibility of test scheduling, as well as advantageous to schools and other testing centers in terms of both space and…

  10. Reliability, validity and administrative burden of the community reintegration of injured service members computer adaptive test (CRIS-CAT)”

    PubMed Central

    2012-01-01

    Background The Computer Adaptive Test version of the Community Reintegration of Injured Service Members measure (CRIS-CAT) consists of three scales measuring Extent of, Perceived Limitations in, and Satisfaction with community integration. The CRIS-CAT was developed using item response theory methods. The purposes of this study were to assess the reliability, concurrent, known group and predictive validity and respondent burden of the CRIS-CAT. The CRIS-CAT was developed using item response theory methods. The purposes of this study were to assess the reliability, concurrent, known group and predictive validity and respondent burden of the CRIS-CAT. Methods This was a three-part study that included a 1) a cross-sectional field study of 517 homeless, employed, and Operation Enduring Freedom / Operation Iraqi Freedom (OEF/OIF) Veterans; who completed all items in the CRIS item set, 2) a cohort study with one year follow-up study of 135 OEF/OIF Veterans, and 3) a 50-person study of CRIS-CAT administration. Conditional reliability of simulated CAT scores was calculated from the field study data, and concurrent validity and known group validity were examined using Pearson product correlations and ANOVAs. Data from the cohort were used to examine the ability of the CRIS-CAT to predict key one year outcomes. Data from the CRIS-CAT administration study were used to calculate ICC (2,1) minimum detectable change (MDC), and average number of items used during CAT administration. Results Reliability scores for all scales were above 0.75, but decreased at both ends of the score continuum. CRIS-CAT scores were correlated with concurrent validity indicators and differed significantly between the three Veteran groups (P < .001). The odds of having any Emergency Room visits were reduced for Veterans with better CRIS-CAT scores (Extent, Perceived Satisfaction respectively: OR = 0.94, 0.93, 0.95; P < .05). CRIS-CAT scores were predictive of SF-12 physical and mental

  11. Genetic testing in domestic cats.

    PubMed

    Lyons, Leslie A

    2012-12-01

    Varieties of genetic tests are currently available for the domestic cat that support veterinary health care, breed management, species identification, and forensic investigations. Approximately thirty-five genes contain over fifty mutations that cause feline health problems or alterations in the cat's appearance. Specific genes, such as sweet and drug receptors, have been knocked-out of Felidae during evolution and can be used along with mtDNA markers for species identification. Both STR and SNP panels differentiate cat race, breed, and individual identity, as well as gender-specific markers to determine sex of an individual. Cat genetic tests are common offerings for commercial laboratories, allowing both the veterinary clinician and the private owner to obtain DNA test results. This article will review the genetic tests for the domestic cat, and their various applications in different fields of science. Highlighted are genetic tests specific to the individual cat, which are a part of the cat's genome.

  12. Computer adaptive testing.

    PubMed

    Gershon, Richard C

    2005-01-01

    The creation of item response theory (IRT) and Rasch models, inexpensive accessibility to high speed desktop computers, and the growth of the Internet, has led to the creation and growth of computerized adaptive testing or CAT. This form of assessment is applicable for both high stakes tests such as certification or licensure exams, as well as health related quality of life surveys. This article discusses the historical background of CAT including its many advantages over conventional (typically paper and pencil) alternatives. The process of CAT is then described including descriptions of the specific differences of using CAT based upon 1-, 2- and 3-parameter IRT and various Rasch models. Numerous specific topics describing CAT in practice are described including: initial item selection, content balancing, test difficulty, test length and stopping rules. The article concludes with the author's reflections regarding the future of CAT.

  13. An Introduction to the Computerized Adaptive Testing

    ERIC Educational Resources Information Center

    Tian, Jian-quan; Miao, Dan-min; Zhu, Xia; Gong, Jing-jing

    2007-01-01

    Computerized adaptive testing (CAT) has unsurpassable advantages over traditional testing. It has become the mainstream in large scale examinations in modern society. This paper gives a brief introduction to CAT including differences between traditional testing and CAT, the principles of CAT, psychometric theory and computer algorithms of CAT, the…

  14. Letting the CAT out of the Bag: Comparing Computer Adaptive Tests and an Eleven-Item Short Form of the Roland-Morris Disability Questionnaire

    PubMed Central

    Cook, Karon F.; Choi, Seung W.; Crane, Paul K.; Deyo, Richard A.; Johnson, Kurt L.; Amtmann, Dagmar

    2009-01-01

    Study Design A post-hoc simulation of a computer adaptive administration of the items of a modified version of the Roland Morris Disability Questionnaire. Objective To evaluate the effectiveness of adaptive administration of back pain-related disability items compared to a fixed 11-item short form. Summary of Background Data Short form versions of the Roland Morris Disability Questionnaire have been developed. An alternative to paper-and -pencil short forms is to administer items adaptively so that items are presented based on a person’s responses to previous items. Theoretically, this allows precise estimation of back pain disability with administration of only a few items. Materials and Methods Data were gathered from two previously conducted studies of persons with back pain. An item response theory model was used to calibrate scores based on all items, items of a paper-and-pencil short form, and several computer adaptive tests (CATs). Results Correlations between each CAT condition and scores based on a 23-item version of the Roland Morris Disability Questionnaire ranged from 0.93 to 0.98. Compared to an 11-item short form, an 11-item CAT produced scores that were significantly more highly correlated with scores based on the 23-item scale. CATs with even fewer items also produced scores that were highly correlated with scores based on all items. For example, scores from a five-item CAT had a correlation of 0.93 with full scale scores. Seven- and nine-item CATs correlated at 0.95 and 0.97, respectively. A CAT with a standard-error-based stopping rule produced scores that correlated at 0.95 with full scale scores. Conclusions A CAT-based back pain-related disability measure may be a valuable tool for use in clinical and research contexts. Use of CAT for other common measures in back pain research, such as other functional scales or measures of psychological distress, may offer similar advantages. PMID:18496352

  15. Is cognitive adaptation training (CAT) compensatory, restorative, or both?

    PubMed

    Fredrick, Megan M; Mintz, Jim; Roberts, David L; Maples, Natalie J; Sarkar, Sonali; Li, Xueying; Velligan, Dawn I

    2015-08-01

    Cognitive adaptation training (CAT) is a psychosocial treatment incorporating environmental supports including signs, checklists to bypass the cognitive deficits of schizophrenia. Our objective was to examine the association between CAT, functional outcomes, and cognitive test performance (cognition). The two research questions were as follows: 1) Does cognition mediate the effect of CAT intervention on functional outcome? 2) Does CAT impact cognitive test performance? A total of 120 participants with schizophrenia were randomized to one of three treatments: 1) CAT (weekly for 9months; monthly thereafter), 2) generic environmental supports (given to participants on clinic visits to promote adaptive behavior), or 3) treatment as usual (TAU). Assessments of cognition and functional outcome were conducted at baseline, 9 and 24months. Mediation analyses and mixed effects regression were conducted. Mediation analyses revealed that during the initial 9months, the direct path from treatment group to functional outcome on the primary measure was positive and highly significant. CAT significantly improved functional outcome compared to the other treatments. However, paths involving cognition were negligible. There was no evidence that cognition mediated improvement in functional outcomes. At 24months, cognition improved more in CAT compared to other treatment groups. The test for cognition mediating improvement in functional outcomes was not significant at this time point. However, improvement in functional outcome led to better performance on cognitive testing. We concluded that improvement in cognition is not a necessary condition for improvement in functional outcome and that greater engagement in functional behavior has a positive impact on cognition.

  16. Complex adaptive therapeutic strategy (CATS) for cancer.

    PubMed

    Cho, Yong Woo; Kim, Sang Yoon; Kwon, Ick Chan; Kim, In-San

    2014-02-10

    Tumors begin with a single cell, but as each tumor grows and evolves, it becomes a wide collection of clones that display remarkable heterogeneity in phenotypic features, which has posed a big challenge to current targeted anticancer therapy. Intra- and inter-tumoral heterogeneity is attributable in part to genetic mutations but also to adaptation and evolution of tumors to heterogeneity in tumor microenvironments. If tumors are viewed not only as a disease but also as a complex adaptive system (CAS), tumors should be treated as such and a more systemic approach is needed. Some of many tumors therapeutic strategies are discussed here from a view of a tumor as CAS, which can be collectively called a complex adaptive therapeutic strategy (CATS). The central theme of CATS is based on three intermediate concepts: i) disruption of artifacts, ii) disruption of connections, and iii) reprogramming of cancer-immune dynamics. Each strategy presented here is a piece of the puzzle for CATS. Although each piece by itself may be neither novel nor profound, an assembled puzzle could be a novel and innovative cancer therapeutic strategy.

  17. Convergent Validity of the Patient Reported Outcomes Measurement Information System's (PROMIS) Physical Function Computerized Adaptive Test (PF-CAT) for the Knee and Shoulder Injury Sports Medicine Patient Population

    PubMed Central

    Robins, Richard Judd; Zhang, Yingying; Anderson, Mike B.; Presson, Angela P.; Burks, Robert T.; Greis, Patrick E.

    2015-01-01

    Objectives: The Patient Reported Outcomes Measurement Instrument System (PROMIS) Physical Function Computer Adaptive Test (PF-CAT) has been developed by the National Institutes of Health as a means of providing validated outcomes scores. PF-CAT adapts to patient response by applying different validated questions based on prior responses to generate scores using between 4 to 12 questions, and has been validated in a variety of patient populations to assess physical function. The purpose of our study is to compare patient reported outcomes scores in a sports medicine (shoulder and knee injury) patient population by analyzing convergence validity of PF-CAT to IKDC, SST, ASES, and SANE scores. We also wanted to assess and compare time burden placed on patients in completing these outcomes scores. Methods: All patient visits from April through September 2014 presenting with either knee or shoulder complaints were included from a university-based sports medicine clinic, during which both PF-CAT as well as SANE, SST, and ASES legacy outcomes scores for shoulder injury patients, and SANE and IKDC outcomes scores for knee injury patients were obtained via tablet during the initial part of each visit. A total of 415 shoulder and 450 knee clinical evaluations qualified for inclusion in the study. Spearman correlation was used to evaluate pair-wise agreement among outcomes scores. The total scores from each outcome test and the T-scores from the PF-CAT were used in this correlation analysis. For interpretation, results greater than 0.5-0.69 were considered to have fair correlation, while values greater than 0.7 were considered as having good correlation. Significance was assessed at the 0.05 level. Median and interquartile ranges were used to summarize scores. The minimum score (floor effects) and maximum score (ceiling effects) occurrences were tallied and reported as percentages. A Fishers exact test was used to test for a difference in the number of times floor and ceiling

  18. Psychometrics behind Computerized Adaptive Testing.

    PubMed

    Chang, Hua-Hua

    2015-03-01

    The paper provides a survey of 18 years' progress that my colleagues, students (both former and current) and I made in a prominent research area in Psychometrics-Computerized Adaptive Testing (CAT). We start with a historical review of the establishment of a large sample foundation for CAT. It is worth noting that the asymptotic results were derived under the framework of Martingale Theory, a very theoretical perspective of Probability Theory, which may seem unrelated to educational and psychological testing. In addition, we address a number of issues that emerged from large scale implementation and show that how theoretical works can be helpful to solve the problems. Finally, we propose that CAT technology can be very useful to support individualized instruction on a mass scale. We show that even paper and pencil based tests can be made adaptive to support classroom teaching.

  19. Individual Differences in Computerized Adaptive Testing.

    ERIC Educational Resources Information Center

    Kim, JinGyu

    Research on the major computerized adaptive testing (CAT) strategies is reviewed, and some findings are reported that examine effects of examinee demographic and psychological characteristics on CAT strategies. In fixed branching strategies, all examinees respond to a common routing test, the score of which is used to assign examinees to a…

  20. Balancing Flexible Constraints and Measurement Precision in Computerized Adaptive Testing

    ERIC Educational Resources Information Center

    Moyer, Eric L.; Galindo, Jennifer L.; Dodd, Barbara G.

    2012-01-01

    Managing test specifications--both multiple nonstatistical constraints and flexibly defined constraints--has become an important part of designing item selection procedures for computerized adaptive tests (CATs) in achievement testing. This study compared the effectiveness of three procedures: constrained CAT, flexible modified constrained CAT,…

  1. 9 CFR 113.39 - Cat safety tests.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false Cat safety tests. 113.39 Section 113... Procedures § 113.39 Cat safety tests. The safety tests provided in this section shall be conducted when... recommended for use in cats. (a) The cat safety test provided in this paragraph shall be used when the...

  2. 9 CFR 113.39 - Cat safety tests.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false Cat safety tests. 113.39 Section 113... Procedures § 113.39 Cat safety tests. The safety tests provided in this section shall be conducted when... recommended for use in cats. (a) The cat safety test provided in this paragraph shall be used when the...

  3. 9 CFR 113.39 - Cat safety tests.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 1 2012-01-01 2012-01-01 false Cat safety tests. 113.39 Section 113... Procedures § 113.39 Cat safety tests. The safety tests provided in this section shall be conducted when... recommended for use in cats. (a) The cat safety test provided in this paragraph shall be used when the...

  4. 9 CFR 113.39 - Cat safety tests.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false Cat safety tests. 113.39 Section 113... Procedures § 113.39 Cat safety tests. The safety tests provided in this section shall be conducted when... recommended for use in cats. (a) The cat safety test provided in this paragraph shall be used when the...

  5. 9 CFR 113.39 - Cat safety tests.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Cat safety tests. 113.39 Section 113... Procedures § 113.39 Cat safety tests. The safety tests provided in this section shall be conducted when... recommended for use in cats. (a) The cat safety test provided in this paragraph shall be used when the...

  6. Test Anxiety, Computer-Adaptive Testing and the Common Core

    ERIC Educational Resources Information Center

    Colwell, Nicole Makas

    2013-01-01

    This paper highlights the current findings and issues regarding the role of computer-adaptive testing in test anxiety. The computer-adaptive test (CAT) proposed by one of the Common Core consortia brings these issues to the forefront. Research has long indicated that test anxiety impairs student performance. More recent research indicates that…

  7. Skilled but Unaware of It: CAT Undermines a Test Taker's Metacognitive Competence

    ERIC Educational Resources Information Center

    Ortner, Tuulia M.; Weisskopf, Eva; Gerstenberg, Friederike X. R.

    2013-01-01

    We investigated students' metacognitive experiences with regard to feelings of difficulty (FD), feelings of satisfaction (FS), and estimate of effort (EE), employing either computerized adaptive testing (CAT) or computerized fixed item testing (FIT). In an experimental approach, 174 students in grades 10 to 13 were tested either with a CAT or a…

  8. A "Rearrangement Procedure" for Scoring Adaptive Tests with Review Options

    ERIC Educational Resources Information Center

    Papanastasiou, Elena C.; Reckase, Mark D.

    2007-01-01

    Because of the increased popularity of computerized adaptive testing (CAT), many admissions tests, as well as certification and licensure examinations, have been transformed from their paper-and-pencil versions to computerized adaptive versions. A major difference between paper-and-pencil tests and CAT from an examinee's point of view is that in…

  9. A Monte Carlo Approach for Adaptive Testing with Content Constraints

    ERIC Educational Resources Information Center

    Belov, Dmitry I.; Armstrong, Ronald D.; Weissman, Alexander

    2008-01-01

    This article presents a new algorithm for computerized adaptive testing (CAT) when content constraints are present. The algorithm is based on shadow CAT methodology to meet content constraints but applies Monte Carlo methods and provides the following advantages over shadow CAT: (a) lower maximum item exposure rates, (b) higher utilization of the…

  10. Evaluating Content Alignment in Computerized Adaptive Testing

    ERIC Educational Resources Information Center

    Wise, Steven L.; Kingsbury, G. Gage; Webb, Norman L.

    2015-01-01

    The alignment between a test and the content domain it measures represents key evidence for the validation of test score inferences. Although procedures have been developed for evaluating the content alignment of linear tests, these procedures are not readily applicable to computerized adaptive tests (CATs), which require large item pools and do…

  11. Computerized Adaptive Testing for Effective and Efficient Measurement in Counseling and Education

    ERIC Educational Resources Information Center

    Weiss, David J.

    2004-01-01

    Computerized adaptive testing (CAT) is described and compared with conventional tests, and its advantages summarized. Some item response theory concepts used in CAT are summarized and illustrated. The author describes the potential usefulness of CAT in counseling and education and reviews some current issues in the implementation of CAT.

  12. Direct and Inverse Problems of Item Pool Design for Computerized Adaptive Testing

    ERIC Educational Resources Information Center

    Belov, Dmitry I.; Armstrong, Ronald D.

    2009-01-01

    The recent literature on computerized adaptive testing (CAT) has developed methods for creating CAT item pools from a large master pool. Each CAT pool is designed as a set of nonoverlapping forms reflecting the skill levels of an assumed population of test takers. This article presents a Monte Carlo method to obtain these CAT pools and discusses…

  13. Robustness of Adaptive Testing to Multidimensionality.

    ERIC Educational Resources Information Center

    Weiss, David J.; Suhadolnik, Debra

    The present monte carlo simulation study was designed to examine the effects of multidimensionality during the administration of computerized adaptive testing (CAT). It was assumed that multidimensionality existed in the individuals to whom test items were being administered, i.e., that the correct or incorrect responses given by an individual…

  14. A Guide to Computer Adaptive Testing Systems

    ERIC Educational Resources Information Center

    Davey, Tim

    2011-01-01

    Some brand names are used generically to describe an entire class of products that perform the same function. "Kleenex," "Xerox," "Thermos," and "Band-Aid" are good examples. The term "computerized adaptive testing" (CAT) is similar in that it is often applied uniformly across a diverse family of testing methods. Although the various members of…

  15. Efficiently Measuring Dimensions of the Externalizing Spectrum Model: Development of the Externalizing Spectrum Inventory-Computerized Adaptive Test (ESI-CAT).

    PubMed

    Sunderland, Matthew; Slade, Tim; Krueger, Robert F; Markon, Kristian E; Patrick, Christopher J; Kramer, Mark D

    2016-11-14

    The development of the Externalizing Spectrum Inventory (ESI) was motivated by the need to comprehensively assess the interrelated nature of externalizing psychopathology and personality using an empirically driven framework. The ESI measures 23 theoretically distinct yet related unidimensional facets of externalizing, which are structured under 3 superordinate factors representing general externalizing, callous aggression, and substance abuse. One limitation of the ESI is its length at 415 items. To facilitate the use of the ESI in busy clinical and research settings, the current study sought to examine the efficiency and accuracy of a computerized adaptive version of the ESI. Data were collected over 3 waves and totaled 1,787 participants recruited from undergraduate psychology courses as well as male and female state prisons. A series of 6 algorithms with different termination rules were simulated to determine the efficiency and accuracy of each test under 3 different assumed distributions. Scores generated using an optimal adaptive algorithm evidenced high correlations (r > .9) with scores generated using the full ESI, brief ESI item-based factor scales, and the 23 facet scales. The adaptive algorithms for each facet administered a combined average of 115 items, a 72% decrease in comparison to the full ESI. Similarly, scores on the item-based factor scales of the ESI-brief form (57 items) were generated using on average of 17 items, a 70% decrease. The current study successfully demonstrates that an adaptive algorithm can generate similar scores for the ESI and the 3 item-based factor scales using a fraction of the total item pool. (PsycINFO Database Record

  16. Variable-Length Computerized Adaptive Testing: Adaptation of the A-Stratified Strategy in Item Selection with Content Balancing

    ERIC Educational Resources Information Center

    Huo, Yan

    2009-01-01

    Variable-length computerized adaptive testing (CAT) can provide examinees with tailored test lengths. With the fixed standard error of measurement ("SEM") termination rule, variable-length CAT can achieve predetermined measurement precision by using relatively shorter tests compared to fixed-length CAT. To explore the application of…

  17. Mutual Information Item Selection Method in Cognitive Diagnostic Computerized Adaptive Testing with Short Test Length

    ERIC Educational Resources Information Center

    Wang, Chun

    2013-01-01

    Cognitive diagnostic computerized adaptive testing (CD-CAT) purports to combine the strengths of both CAT and cognitive diagnosis. Cognitive diagnosis models aim at classifying examinees into the correct mastery profile group so as to pinpoint the strengths and weakness of each examinee whereas CAT algorithms choose items to determine those…

  18. Hypo-osmotic test in cat spermatozoa.

    PubMed

    Comercio, E A; Monachesi, N E; Loza, M E; Gambarotta, M; Wanke, M M

    2013-10-01

    The hypo-osmotic (HOS) test has been used in other species as an indicator of the fertilising capacity of spermatozoa. The aims of this study were to assess the response of domestic cat spermatozoa to the hypo-osmotic test, to determine the type of solution, concentration and time of incubation needed to obtain a maximum percentage of swelling, to correlate the selected combination with the percentages of progressive motility and to evaluate whether dilution of the ejaculate alters the results. Incubation for 30 and 45 min in solutions of fructose and of citrate of 50 and 100 mOsmol kg⁻¹ was evaluated. The highest percentage of swelling was obtained using the 50 mOsmol kg⁻¹ solution, and no significant differences were observed between the times of exposure to the solutions. A positive correlation was observed between the percentage of individual progressive motility and the percentage of sperm swelling in a 50 mOsmol kg⁻¹ fructose solution, with no significant differences being observed between raw and diluted semen samples. The results of this study suggest that the HOS test could be useful for evaluating membrane function in domestic cat spermatozoa, both in raw semen and in samples diluted in the EZ Mixin® commercial extender, and thus could be incorporated into routine semen evaluation protocols.

  19. Triglyceride response following an oral fat tolerance test in Burmese cats, other pedigree cats and domestic crossbred cats.

    PubMed

    Kluger, Elissa K; Hardman, Chloë; Govendir, Merran; Baral, Randolph M; Sullivan, David R; Snow, David; Malik, Richard

    2009-02-01

    Primary lipid disorders causing fasting triglyceridaemia have been documented infrequently in Burmese cats. Due to the known increased risk of diabetes mellitus and sporadic reports of lipid aqueous in this breed, the aim of this study was to determine whether healthy Burmese cats displayed a more pronounced pre- or post-prandial triglyceridaemia compared to other cats. Serum triglyceride (TG) concentrations were determined at baseline and variably at 2, 4 and 6h after ingestion of a high-fat meal (ie, an oral fat tolerance test) in a representative sample of Burmese and non-Burmese cats. The median 4 and 6h serum TG concentrations were significantly higher in Burmese cats (4h - 2.8mmol/l; 6h - 8.2mmol/l) than in other pedigree and domestic crossbred cats (4h - 1.5mmol/l; 6h - 1.0mmol/l). The non-Burmese group had post-prandial TG concentrations ranging from 0.6 to 3.9mmol/l. Seven Burmese cats had post-prandial TG concentrations between 6.6 and 19.0mmol/l, five had concentrations between 4.2 and 4.7mmol/l, while the remaining 15 had post-prandial concentrations between 0.5 and 2.8mmol/l. None of these Burmese cats had fasting triglyceridaemia. Most Burmese cats with a 4 h TG > 6.0 mmol/l had elevated fasting very low density lipoprotein (VLDL) concentrations. This study demonstrates that a proportion of Burmese cats in Australia have delayed TG clearance compared to other cats. The potential repercussions of this observation with reference to lipid aqueous, pancreatitis and diabetes mellitus in Burmese cats are discussed.

  20. An Adaptive Testing System for Supporting Versatile Educational Assessment

    ERIC Educational Resources Information Center

    Huang, Yueh-Min; Lin, Yen-Ting; Cheng, Shu-Chen

    2009-01-01

    With the rapid growth of computer and mobile technology, it is a challenge to integrate computer based test (CBT) with mobile learning (m-learning) especially for formative assessment and self-assessment. In terms of self-assessment, computer adaptive test (CAT) is a proper way to enable students to evaluate themselves. In CAT, students are…

  1. Assessing the Efficiency of Item Selection in Computerized Adaptive Testing.

    ERIC Educational Resources Information Center

    Weissman, Alexander

    This study investigated the efficiency of item selection in a computerized adaptive test (CAT), where efficiency was defined in terms of the accumulated test information at an examinee's true ability level. A simulation methodology compared the efficiency of 2 item selection procedures with 5 ability estimation procedures for CATs of 5, 10, 15,…

  2. Adaptation of cat motoneurons to sustained and intermittent extracellular activation.

    PubMed Central

    Spielmann, J M; Laouris, Y; Nordstrom, M A; Robinson, G A; Reinking, R M; Stuart, D G

    1993-01-01

    1. The main purpose of this study was to quantify the adaptation of spinal motoneurons to sustained and intermittent activation, using an extracellular route of stimulating current application to single test cells, in contrast to an intracellular route, as has been used previously. In addition, associations were tested between firing rate properties of the tested cells and other type (size)-related properties of these cells and their motor units. 2. Motoneurons supplying the medial gastrocnemius muscle of the deeply anaesthetized cat were stimulated for 240 s with microelectrodes which passed sustained extracellular current at 1.25 times the threshold for repetitive firing. Many cells were also tested following a rest period with intermittent 1 s current pulses (duration 600 ms) at the same relative stimulus strength. Cell discharge was assessed from the EMG of the motor unit innervated by the test neuron. The motoneurons and their motor units were assigned to four categories (i.e. types FF, FR, S and F; where F = FF + FR) based on conventional criteria. In all, twenty F (16 FF, 4 FR) and fourteen S cells were studied with sustained stimulation. Thirty of these cells (17 F, 13 S) and an additional two cells (1 F, 1 S) were studied with intermittent stimulation. 3. The mean threshold current required for sustained firing for a period of > or = 2 s was not significantly different for F and S cells. However, most of the other measured parameters of motoneuron firing differed significantly for these two cell groups. For example, at 1.25 times the threshold current for repetitive firing, the mean firing duration in response to 240 s of sustained activation was 123 +/- 88 s (+/- S.D.) for F cells vs. 233 +/- 19 s for S cells. These values were significantly longer than those from a comparable, previously reported study that employed intracellular stimulation. With intermittent stimulation, the firing durations of F and S cells were not significantly different from each

  3. Case Studies in Computer Adaptive Test Design through Simulation.

    ERIC Educational Resources Information Center

    Eignor, Daniel R.; And Others

    The extensive computer simulation work done in developing the computer adaptive versions of the Graduate Record Examinations (GRE) Board General Test and the College Board Admissions Testing Program (ATP) Scholastic Aptitude Test (SAT) is described in this report. Both the GRE General and SAT computer adaptive tests (CATs), which are fixed length…

  4. Application of the Bifactor Model to Computerized Adaptive Testing

    ERIC Educational Resources Information Center

    Seo, Dong Gi

    2011-01-01

    Most computerized adaptive tests (CAT) have been studied under the framework of unidimensional item response theory. However, many psychological variables are multidimensional and might benefit from using a multidimensional approach to CAT. In addition, a number of psychological variables (e.g., quality of life, depression) can be conceptualized…

  5. DIF Analysis for Pretest Items in Computer-Adaptive Testing.

    ERIC Educational Resources Information Center

    Zwick, Rebecca; And Others

    A simulation study of methods of assessing differential item functioning (DIF) in computer-adaptive tests (CATs) was conducted by Zwick, Thayer, and Wingersky (in press, 1993). Results showed that modified versions of the Mantel-Haenszel and standardization methods work well with CAT data. DIF methods were also investigated for nonadaptive…

  6. A Framework for the Development of Computerized Adaptive Tests

    ERIC Educational Resources Information Center

    Thompson, Nathan A.; Weiss, David J.

    2011-01-01

    A substantial amount of research has been conducted over the past 40 years on technical aspects of computerized adaptive testing (CAT), such as item selection algorithms, item exposure controls, and termination criteria. However, there is little literature providing practical guidance on the development of a CAT. This paper seeks to collate some…

  7. The Effect of Test and Examinee Characteristics on the Occurrence of Aberrant Response Patterns in a Computerized Adaptive Test

    ERIC Educational Resources Information Center

    Rizavi, Saba; Hariharan, Swaminathan

    2001-01-01

    The advantages that computer adaptive testing offers over linear tests have been well documented. The Computer Adaptive Test (CAT) design is more efficient than the Linear test design as fewer items are needed to estimate an examinee's proficiency to a desired level of precision. In the ideal situation, a CAT will result in examinees answering…

  8. Person Fit Analysis in Computerized Adaptive Testing Using Tests for a Change Point

    ERIC Educational Resources Information Center

    Sinharay, Sandip

    2016-01-01

    Meijer and van Krimpen-Stoop noted that the number of person-fit statistics (PFSs) that have been designed for computerized adaptive tests (CATs) is relatively modest. This article partially addresses that concern by suggesting three new PFSs for CATs. The statistics are based on tests for a change point and can be used to detect an abrupt change…

  9. Impact of Local Item Dependence on Item Response Theory Scoring in CAT. Law School Admission Council Computerized Testing Report. LSAC Research Report Series.

    ERIC Educational Resources Information Center

    Reese, Lynda M.

    This study represented a first attempt to evaluate the impact of local item dependence (LID) for Item Response Theory (IRT) scoring in computerized adaptive testing (CAT). The most basic CAT design and a simplified design for simulating CAT item pools with varying degrees of LID were applied. A data generation method that allows the LID among…

  10. Test Design Optimization in CAT Early Stage with the Nominal Response Model

    ERIC Educational Resources Information Center

    Passos, Valeria Lima; Berger, Martijn P. F.; Tan, Frans E.

    2007-01-01

    The early stage of computerized adaptive testing (CAT) refers to the phase of the trait estimation during the administration of only a few items. This phase can be characterized by bias and instability of estimation. In this study, an item selection criterion is introduced in an attempt to lessen this instability: the D-optimality criterion. A…

  11. Cats

    MedlinePlus

    ... Patients Infants and Young Children Publications & Materials Announcements Cats Recommend on Facebook Tweet Share Compartir Overview Diseases ... hand washing whenever you play or work with cats Wash your hands with soap and running water ...

  12. "Computerized Adaptive Testing: Theory and Practice." Wim J. van der Linden and Cees A. W. Glas, Eds. [book review].

    ERIC Educational Resources Information Center

    Reise, Steven P.

    2001-01-01

    This book contains a series of research articles about computerized adaptive testing (CAT) written for advanced psychometricians. The book is divided into sections on: (1) item selection and examinee scoring in CAT; (2) examples of CAT applications; (3) item banks; (4) determining model fit; and (5) using testlets in CAT. (SLD)

  13. Mucopolysaccharidosis VI in cats - clarification regarding genetic testing.

    PubMed

    Lyons, Leslie A; Grahn, Robert A; Genova, Francesca; Beccaglia, Michela; Hopwood, John J; Longeri, Maria

    2016-07-02

    The release of new DNA-based diagnostic tools has increased tremendously in companion animals. Over 70 different DNA variants are now known for the cat, including DNA variants in disease-associated genes and genes causing aesthetically interesting traits. The impact genetic tests have on animal breeding and health management is significant because of the ability to control the breeding of domestic cats, especially breed cats. If used properly, genetic testing can prevent the production of diseased animals, causing the reduction of the frequency of the causal variant in the population, and, potentially, the eventual eradication of the disease. However, testing of some identified DNA variants may be unwarranted and cause undo strife within the cat breeding community and unnecessary reduction of gene pools and availability of breeding animals. Testing for mucopolysaccharidosis Type VI (MPS VI) in cats, specifically the genetic testing of the L476P (c.1427T>C) and the D520N (c.1558G>A) variants in arylsulfatase B (ARSB), has come under scrutiny. No health problems are associated with the D520N (c.1558G>A) variant, however, breeders that obtain positive results for this variant are speculating as to possible correlation with health concerns. Birman cats already have a markedly reduced gene pool and have a high frequency of the MPS VI D520N variant. Further reduction of the gene pool by eliminating cats that are heterozygous or homozygous for only the MPS VI D520N variant could lead to more inbreeding depression effects on the breed population. Herein is debated the genetic testing of the MPS VI D520N variant in cats. Surveys from different laboratories suggest the L476P (c.1427T>C) disease-associated variant should be monitored in the cat breed populations, particularly breeds with Siamese derivations and outcrosses. However, the D520N has no evidence of association with disease in cats and testing is not recommended in the absence of L476P genotyping. Selection

  14. Best Design for Multidimensional Computerized Adaptive Testing with the Bifactor Model

    ERIC Educational Resources Information Center

    Seo, Dong Gi; Weiss, David J.

    2015-01-01

    Most computerized adaptive tests (CATs) have been studied using the framework of unidimensional item response theory. However, many psychological variables are multidimensional and might benefit from using a multidimensional approach to CATs. This study investigated the accuracy, fidelity, and efficiency of a fully multidimensional CAT algorithm…

  15. Immunophenotyping of the cutaneous cellular infiltrate after atopy patch testing in cats with atopic dermatitis.

    PubMed

    Roosje, P J; Thepen, T; Rutten, V P M G; van den Brom, W E; Bruijnzeel-Koomen, C A F M; Willemse, T

    2004-10-01

    Cats with spontaneously occurring atopic dermatitis have clinical and immunocytochemical characteristics compatible with these in humans with atopic dermatitis (AD). The atopy patch test (APT) has proven to be a valuable tool in elucidating the disease process in humans. Additionally, the APT is very specific and bypasses the problem of conflicting results due to differences in chronicity of lesions of AD patients. We adapted the APT for use in cats to explore the suitability of the APT as a tool to study the onset of allergic inflammation in cats with atopic dermatitis. APT were performed in AD cats (n = 6) and healthy cats (n = 10). All cats were patch tested with two allergens in three different dilutions and a diluent control. The allergens for the APT were selected from positive intradermal test and /or prick test results and consisted of: Dermatophagoides farinae, D. pteronyssinus, Tyrophagus putrescentiae, and a grass pollen mixture. APT were read after 10, 24 and 48 h, and punch biopsies for immunohistochemical evaluation were collected at these time points. Macroscopically positive APT reactions were observed in three out of six cats at 24 and/or 48 h with allergen concentrations of 25,000 and 100,000 NU/ml. Reactions were not observed at negative control sites and neither in control animals. A significantly increased number of IL-4+, CD4+, CD3+, MHC class II+ and CD1a+ cells was found in one AD cat with positive APT reactions. Five out of six AD cats had significantly increased IL-4+ T cell numbers at 24 and/or 48 h. Our data indicate that in cats, macroscopically positive patch test reactions can be induced, which have a cellular infiltrate similar to that in lesional skin. We found a high specificity and a macroscopically positive APT reaction in half of the cats, which is similar to what is seen in humans. Hence, the APT in cats might be a useful tool in studying the immunopathogenesis of feline atopic dermatitis.

  16. Development and Evaluation of a Confidence-Weighting Computerized Adaptive Testing

    ERIC Educational Resources Information Center

    Yen, Yung-Chin; Ho, Rong-Guey; Chen, Li-Ju; Chou, Kun-Yi; Chen, Yan-Lin

    2010-01-01

    The purpose of this study was to examine whether the efficiency, precision, and validity of computerized adaptive testing (CAT) could be improved by assessing confidence differences in knowledge that examinees possessed. We proposed a novel polytomous CAT model called the confidence-weighting computerized adaptive testing (CWCAT), which combined a…

  17. A computerized adaptive test for enterprising personality assessment in youth.

    PubMed

    Pedrosa, Ignacio; Suárez-Álvarez, Javier; García-Cueto, Eduardo; Muñiz, José

    2016-11-01

    Backgound : Assessing specific personality traits has shown better predictive power of enterprising personality than have broad personality traits. Hitherto, there have been no instruments that evaluate the combination of specific personality traits of enterprising personality in an adaptive format. So, the aim was to develop a Computerized Adaptive Test (CAT) to assess enterprising personality in young people.

  18. The Communication Attitude Test (CAT-S): Normative Values for 220 Swedish Children

    ERIC Educational Resources Information Center

    Johannisson, Tove B.; Wennerfeldt, Susanna; Havstam, Christina; Naeslund, Maria; Jacobson, Kajsa; Lohmander, Anette

    2009-01-01

    Background: The risk of developing a negative attitude to communication as a consequence of having a speech disorder has been in focus for decades in research concerning fluency disorders in relation to both children and adults. The Communication Attitude Test (CAT), which was created to measure children's attitudes towards their own…

  19. Application of computerized adaptive testing in medical education.

    PubMed

    Huh, Sun

    2009-06-01

    Application of computerized adaptive testing (CAT) in medical education is still spare in the high stakes examination or in the school-based examination. In the medical school in Belgium, CAT was used for an assessment tool in general practice as pilot test was reported. In Hallym University, CAT has been introduced in the evaluation of the students' performance as in-course general evaluation test and parasitology test. Another examples of application of CAT for high stakes examination are Medical Council of Canada Qualifying Examination - Part 1 in Canada and National Council Licensure EXamination - Registered Nurse in USA. CAT has some merits such as accurate estimation of the ability parameters of the examinees and the shorter period of examination. To apply the CAT in medical education more actively, medical teachers should have an interest in the modern measurement theories such as item response theory and technologies. It is still uncertain if CAT may be prosperous in the medical education as a tool for the measurement of the examinees' ability. However, we should prepare the era of application of CAT in high stakes examination such as medical licensing examination.

  20. Leak test adapter for containers

    DOEpatents

    Hallett, Brian H.; Hartley, Michael S.

    1996-01-01

    An adapter is provided for facilitating the charging of containers and leak testing penetration areas. The adapter comprises an adapter body and stem which are secured to the container's penetration areas. The container is then pressurized with a tracer gas. Manipulating the adapter stem installs a penetration plug allowing the adapter to be removed and the penetration to be leak tested with a mass spectrometer. Additionally, a method is provided for using the adapter.

  1. Simple and Effective Algorithms: Computer-Adaptive Testing.

    ERIC Educational Resources Information Center

    Linacre, John Michael

    Computer-adaptive testing (CAT) allows improved security, greater scoring accuracy, shorter testing periods, quicker availability of results, and reduced guessing and other undesirable test behavior. Simple approaches can be applied by the classroom teacher, or other content specialist, who possesses simple computer equipment and elementary…

  2. Adaptation of a-Stratified Method in Variable Length Computerized Adaptive Testing.

    ERIC Educational Resources Information Center

    Wen, Jian-Bing; Chang, Hua-Hua; Hau, Kit-Tai

    Test security has often been a problem in computerized adaptive testing (CAT) because the traditional wisdom of item selection overly exposes high discrimination items. The a-stratified (STR) design advocated by H. Chang and his collaborators, which uses items of less discrimination in earlier stages of testing, has been shown to be very…

  3. Some Considerations for Eliminating Biases in Ability Estimation in Computerized Adaptive Testing.

    ERIC Educational Resources Information Center

    Samejima, Fumiko

    Item response theory (IRT) has been adapted as the theoretical foundation of computerized adaptive testing (CAT) for several decades. In applying IRT to CAT, there are certain considerations that are essential, and yet tend to be neglected. These essential issues are addressed in this paper, and then several ways of eliminating noise and bias in…

  4. Adaptability of the vestibulo-ocular reflex to vision reversal in strobe reared cats.

    PubMed

    Mandl, G; Melvill Jones, G; Cynader, M

    1981-03-23

    Optical reversal of vision brings about adaptive changes in the vestibulo-ocular reflex (VOR) tending to reduce retinal image slip during head movement. The present experiments investigated this form of adaptation in cats whose complement of direction sensitive central visual cells had been substantially reduced by rearing in 8 Hz stroboscopic light. Horizontal vision reversal was produced by dove prisms carried in a skull-mounted mask. A scleral eye coil was used to measure horizontal eye movements. VOR gain and phase were measured in the dark during sinusoidal rotation using test stimuli of 1/8 Hz and 5- or 20 degrees/sec velocity amplitude. Initially, strobe reared cats produced virtually normal VOR in the dark, except for slight but significant exaggeration of the normal phase advancement to be expected at 1/8 Hz. Addition of their familiar strobe illumination produced almost perfect oculomotor compensation. Maintained vision reversal in both strobe and normal illumination produced similar patterns of adaptive change in normal and strobe reared subjects, i.e. all animals exhibited an initial fast, and subsequent much slower, stage of gain attenuation, with similar changes in phase. Thus, strobe rearing did not prevent the development of an essentially normal VOR, nor did it interfere significantly with the ability to adapt in response to vision reversal. Since strobe rearing depletes direction selective visual movement detectors in the cortex and superior colliculi, it is inferred that signals responsible for activating the adaptive process are probably carried mainly in the accessory optic, rather than cortical and collicular, visual system.

  5. A Conditional Exposure Control Method for Multidimensional Adaptive Testing

    ERIC Educational Resources Information Center

    Finkelman, Matthew; Nering, Michael L.; Roussos, Louis A.

    2009-01-01

    In computerized adaptive testing (CAT), ensuring the security of test items is a crucial practical consideration. A common approach to reducing item theft is to define maximum item exposure rates, i.e., to limit the proportion of examinees to whom a given item can be administered. Numerous methods for controlling exposure rates have been proposed…

  6. Multistage Adaptive Testing for a Large-Scale Classification Test: Design, Heuristic Assembly, and Comparison with Other Testing Modes. ACT Research Report Series, 2012 (6)

    ERIC Educational Resources Information Center

    Zheng, Yi; Nozawa, Yuki; Gao, Xiaohong; Chang, Hua-Hua

    2012-01-01

    Multistage adaptive tests (MSTs) have gained increasing popularity in recent years. MST is a balanced compromise between linear test forms (i.e., paper-and-pencil testing and computer-based testing) and traditional item-level computer-adaptive testing (CAT). It combines the advantages of both. On one hand, MST is adaptive (and therefore more…

  7. Hybrid Computerized Adaptive Testing: From Group Sequential Design to Fully Sequential Design

    ERIC Educational Resources Information Center

    Wang, Shiyu; Lin, Haiyan; Chang, Hua-Hua; Douglas, Jeff

    2016-01-01

    Computerized adaptive testing (CAT) and multistage testing (MST) have become two of the most popular modes in large-scale computer-based sequential testing. Though most designs of CAT and MST exhibit strength and weakness in recent large-scale implementations, there is no simple answer to the question of which design is better because different…

  8. Feline immunodeficiency virus testing in stray, feral, and client-owned cats of Ottawa.

    PubMed

    Little, Susan E

    2005-10-01

    Feline immunodeficiency virus (FIV) seroprevalence is evaluated in 3 groups of cats. Seventy-four unowned urban strays were tested, as well as 20 cats from a small feral cat colony, and 152 client-owned cats. Of the 246 cats tested, 161 (65%) were male and 85 (35%) were female. Seroprevalence for FIV was 23% in the urban strays, 5% in the feral cat colony, and 5.9% in the client-owned cats. Ten cats (4%) were also positive for Feline leukemia virus (FeLV) antigen, including 2 cats coinfected with FeLV and FIV. Seroprevalence for FIV in cats from Ottawa is similar to that found in other nonrandom studies of cats in North America.

  9. Effects of Scale Transformation and Test Termination Rule on the Precision of Ability Estimates in CAT. ACT Research Report Series.

    ERIC Educational Resources Information Center

    Yi, Qing; Wang, Tianyou; Ban, Jae-Chun

    Error indices (bias, standard error of estimation, and root mean square error) obtained on different scales of measurement under different test termination rules in a computerized adaptive test (CAT) context were examined. Four ability estimation methods were studied: (1) maximum likelihood estimation (MLE); (2) weighted likelihood estimation…

  10. The Application of the Monte Carlo Approach to Cognitive Diagnostic Computerized Adaptive Testing With Content Constraints

    ERIC Educational Resources Information Center

    Mao, Xiuzhen; Xin, Tao

    2013-01-01

    The Monte Carlo approach which has previously been implemented in traditional computerized adaptive testing (CAT) is applied here to cognitive diagnostic CAT to test the ability of this approach to address multiple content constraints. The performance of the Monte Carlo approach is compared with the performance of the modified maximum global…

  11. Considering the Use of General and Modified Assessment Items in Computerized Adaptive Testing

    ERIC Educational Resources Information Center

    Wyse, Adam E.; Albano, Anthony D.

    2015-01-01

    This article used several data sets from a large-scale state testing program to examine the feasibility of combining general and modified assessment items in computerized adaptive testing (CAT) for different groups of students. Results suggested that several of the assumptions made when employing this type of mixed-item CAT may not be met for…

  12. Application of Computerized Adaptive Testing to Entrance Examination for Graduate Studies in Turkey

    ERIC Educational Resources Information Center

    Bulut, Okan; Kan, Adnan

    2012-01-01

    Problem Statement: Computerized adaptive testing (CAT) is a sophisticated and efficient way of delivering examinations. In CAT, items for each examinee are selected from an item bank based on the examinee's responses to the items. In this way, the difficulty level of the test is adjusted based on the examinee's ability level. Instead of…

  13. A Multiple Objective Test Assembly Approach for Exposure Control Problems in Computerized Adaptive Testing

    ERIC Educational Resources Information Center

    Veldkamp, Bernard P.; Verschoor, Angela J.; Eggen, Theo J. H. M.

    2010-01-01

    Overexposure and underexposure of items in the bank are serious problems in operational computerized adaptive testing (CAT) systems. These exposure problems might result in item compromise, or point at a waste of investments. The exposure control problem can be viewed as a test assembly problem with multiple objectives. Information in the test has…

  14. Development and Simulation Testing of a Computerized Adaptive Version of the Philadelphia Naming Test

    ERIC Educational Resources Information Center

    Hula, William D.; Kellough, Stacey; Fergadiotis, Gerasimos

    2015-01-01

    Purpose: The purpose of this study was to develop a computerized adaptive test (CAT) version of the Philadelphia Naming Test (PNT; Roach, Schwartz, Martin, Grewal, & Brecher, 1996), to reduce test length while maximizing measurement precision. This article is a direct extension of a companion article (Fergadiotis, Kellough, & Hula, 2015),…

  15. A New Stopping Rule for Computerized Adaptive Testing

    ERIC Educational Resources Information Center

    Choi, Seung W.; Grady, Matthew W.; Dodd, Barbara G.

    2011-01-01

    The goal of the current study was to introduce a new stopping rule for computerized adaptive testing (CAT). The predicted standard error reduction (PSER) stopping rule uses the predictive posterior variance to determine the reduction in standard error that would result from the administration of additional items. The performance of the PSER was…

  16. Computerized Adaptive Testing Using the Partial Credit Model: Effects of Item Pool Characteristics and Different Stopping Rules.

    ERIC Educational Resources Information Center

    Dodd, Barbara G.; And Others

    1993-01-01

    Effects of the following variables on performance of computerized adaptive testing (CAT) procedures for the partial credit model (PCM) were studied: (1) stopping rule for terminating CAT; (2) item pool size; and (3) distribution of item difficulties. Implications of findings for CAT systems based on the PCM are discussed. (SLD)

  17. Development of a Postacute Hospital Item Bank for the New Pediatric Evaluation of Disability Inventory-Computer Adaptive Test

    ERIC Educational Resources Information Center

    Dumas, Helene M.

    2010-01-01

    The PEDI-CAT is a new computer adaptive test (CAT) version of the Pediatric Evaluation of Disability Inventory (PEDI). Additional PEDI-CAT items specific to postacute pediatric hospital care were recently developed using expert reviews and cognitive interviewing techniques. Expert reviews established face and construct validity, providing positive…

  18. Comparison of Item Targeting Strategies for Pass/Fail Computer Adaptive Tests.

    ERIC Educational Resources Information Center

    Bergstrom, Betty A.; Gershon, Richard

    The most useful method of item selection for making pass-fail decisions with a Computerized Adaptive Test (CAT) was studied. Medical technology students (n=86) took a computer adaptive test in which items were targeted to the ability of the examinee. The adaptive algorithm that selected items and estimated person measures used the Rasch model and…

  19. On the Issue of Item Selection in Computerized Adaptive Testing with Response Times

    ERIC Educational Resources Information Center

    Veldkamp, Bernard P.

    2016-01-01

    Many standardized tests are now administered via computer rather than paper-and-pencil format. The computer-based delivery mode brings with it certain advantages. One advantage is the ability to adapt the difficulty level of the test to the ability level of the test taker in what has been termed computerized adaptive testing (CAT). A second…

  20. Measuring Negative and Positive Thoughts in Children: An Adaptation of the Children's Automatic Thoughts Scale (CATS).

    PubMed

    Hogendoorn, Sanne M; Wolters, Lidewij H; Vervoort, Leentje; Prins, Pier J M; Boer, Frits; Kooij, Emelie; de Haan, Else

    2010-10-01

    The aim of this study is to describe the factor structure and psychometric properties of an extended version of the Children's Automatic Thoughts Scale (CATS), the CATS-Negative/Positive (CATS-N/P). The CATS was originally designed to assess negative self-statements in children and adolescents. However, positive thoughts also play a major role in childhood disorders such as anxiety and depression. Therefore, positive self-statements were added to the CATS. The CATS-N/P was administered to a community sample of 554 children aged 8-18 years. The results of a confirmatory factor analysis revealed that the positive self-statements formed a separate and psychometrically sound factor. Internal and short-term test-retest reliability was good. Boys reported more hostile and positive thoughts than girls; and younger children reported more negative thoughts concerning physical threat, social threat, and failure than older children. In conclusion, the results of the current study support the use of the CATS-N/P for the measurement of positive and negative thoughts in children. The application of the CATS-N/P can facilitate further research on cognitive factors in different childhood disorders.

  1. An Investigation of Procedures for Computerized Adaptive Testing Using Partial Credit Scoring.

    ERIC Educational Resources Information Center

    Koch, William R.; Dodd, Barbara G.

    1989-01-01

    Various aspects of the computerized adaptive testing (CAT) procedure for partial credit scoring were manipulated, focusing on the effects of the manipulations on operational characteristics of the CAT. The effects of item-pool size, item-pool information, and stepsizes used along the trait continuum were assessed. (TJH)

  2. A Simulation Study of Methods for Assessing Differential Item Functioning in Computerized Adaptive Tests.

    ERIC Educational Resources Information Center

    Zwick, Rebecca; And Others

    1994-01-01

    Simulated data were used to investigate the performance of modified versions of the Mantel-Haenszel method of differential item functioning (DIF) analysis in computerized adaptive tests (CAT). Results indicate that CAT-based DIF procedures perform well and support the use of item response theory-based matching variables in DIF analysis. (SLD)

  3. Firestar-"D": Computerized Adaptive Testing Simulation Program for Dichotomous Item Response Theory Models

    ERIC Educational Resources Information Center

    Choi, Seung W.; Podrabsky, Tracy; McKinney, Natalie

    2012-01-01

    Computerized adaptive testing (CAT) enables efficient and flexible measurement of latent constructs. The majority of educational and cognitive measurement constructs are based on dichotomous item response theory (IRT) models. An integral part of developing various components of a CAT system is conducting simulations using both known and empirical…

  4. Variable-Length Computerized Adaptive Testing Based on Cognitive Diagnosis Models

    ERIC Educational Resources Information Center

    Hsu, Chia-Ling; Wang, Wen-Chung; Chen, Shu-Ying

    2013-01-01

    Interest in developing computerized adaptive testing (CAT) under cognitive diagnosis models (CDMs) has increased recently. CAT algorithms that use a fixed-length termination rule frequently lead to different degrees of measurement precision for different examinees. Fixed precision, in which the examinees receive the same degree of measurement…

  5. Item Pool Design for an Operational Variable-Length Computerized Adaptive Test

    ERIC Educational Resources Information Center

    He, Wei; Reckase, Mark D.

    2014-01-01

    For computerized adaptive tests (CATs) to work well, they must have an item pool with sufficient numbers of good quality items. Many researchers have pointed out that, in developing item pools for CATs, not only is the item pool size important but also the distribution of item parameters and practical considerations such as content distribution…

  6. The temperature sensitivity of the Type I slowly adapting mechanoreceptors in cats and monkeys

    PubMed Central

    Duclaux, Roland; Kenshalo, Dan R.

    1972-01-01

    1. The sensitivity of Type I slowly adapting mechanoreceptors in cat and monkey skin to temperature and changes in temperature was investigated. 2. Multiple receptors innervated by a single axon appeared to be more frequent in the monkey than in the cat skin. 3. The responses of these receptors to thermal stimulation at static skin temperatures from 27 to 40° C were similar in cats and monkeys. At 43° C the monkey receptors showed a higher steady-state activity than the cat receptors. 4. A maximum steady-state frequency of 5·5 impulses/sec occurred in both the cat and monkey receptors at a static skin temperature of 37° C. 5. The maximum dynamic response to cooling occurred at a skin temperature of 40° C. The response was near its maximum at 2° C cooling and increased but little with further increases in the intensity of cooling. 6. Dynamic responses to cooling disappeared after the skin had been heated to 51° C for 35 sec and to mechanical stimulation after heating to 53° C for 35 sec. Excitation by either mechanical or thermal stimulation did not reappear within 1-2 hr. 7. The response characteristics of the Type I slowly adapting mechanoreceptors to temperature and temperature changes differ from those of specific cold receptors. ImagesFig. 1Fig. 2Fig. 3Fig. 4 PMID:4627267

  7. An Investigation on Computer-Adaptive Multistage Testing Panels for Multidimensional Assessment

    ERIC Educational Resources Information Center

    Wang, Xinrui

    2013-01-01

    The computer-adaptive multistage testing (ca-MST) has been developed as an alternative to computerized adaptive testing (CAT), and been increasingly adopted in large-scale assessments. Current research and practice only focus on ca-MST panels for credentialing purposes. The ca-MST test mode, therefore, is designed to gauge a single scale. The…

  8. Web-Based Adaptive Testing System (WATS) for Classifying Students Academic Ability

    ERIC Educational Resources Information Center

    Lee, Jaemu; Park, Sanghoon; Kim, Kwangho

    2012-01-01

    Computer Adaptive Testing (CAT) has been highlighted as a promising assessment method to fulfill two testing purposes: estimating student academic ability and classifying student academic level. In this paper, assessment for we introduced the Web-based Adaptive Testing System (WATS) developed to support a cost effective assessment for classifying…

  9. Computer-adaptive test to measure community reintegration of Veterans.

    PubMed

    Resnik, Linda; Tian, Feng; Ni, Pengsheng; Jette, Alan

    2012-01-01

    The Community Reintegration of Injured Service Members (CRIS) measure consists of three scales measuring extent of, perceived limitations in, and satisfaction with community reintegration. Length of the CRIS may be a barrier to its widespread use. Using item response theory (IRT) and computer-adaptive test (CAT) methodologies, this study developed and evaluated a briefer community reintegration measure called the CRIS-CAT. Large item banks for each CRIS scale were constructed. A convenience sample of 517 Veterans responded to all items. Exploratory and confirmatory factor analyses (CFAs) were used to identify the dimensionality within each domain, and IRT methods were used to calibrate items. Accuracy and precision of CATs of different lengths were compared with the full-item bank, and data were examined for differential item functioning (DIF). CFAs supported unidimensionality of scales. Acceptable item fit statistics were found for final models. Accuracy of 10-, 15-, 20-, and variable-item CATs for all three scales was 0.88 or above. CAT precision increased with number of items administered and decreased at the upper ranges of each scale. Three items exhibited moderate DIF by sex. The CRIS-CAT demonstrated promising measurement properties and is recommended for use in community reintegration assessment.

  10. New version of the Pediatric Evaluation of Disability Inventory (PEDI-CAT): translation, cultural adaptation to Brazil and analyses of psychometric properties

    PubMed Central

    Mancini, Marisa C.; Coster, Wendy J.; Amaral, Maíra F.; Avelar, Bruna S.; Freitas, Raphael; Sampaio, Rosana F.

    2016-01-01

    ABSTRACT Background The Pediatric Evaluation of Disability Inventory-Computer Adaptive Test (PEDI-CAT), developed with innovative measurement methodologies, evaluates functioning of children and youth, from 0 to 21 years, with different health conditions. It is a revision of an earlier instrument (PEDI) that has been used in national and international clinical practice and research. It was felt to be necessary to make this new version (PEDI-CAT) available in Brazil. Objectives Translate and culturally adapt the PEDI-CAT to the Brazilian-Portuguese language and test its psychometric properties. Method This methodological study was developed through the following stages: (1) translation, (2) synthesis, (3) back-translation, (4) revision by an expert committee, (5) testing of the pre-final version, and (6) evaluation of the psychometric properties. The 276 translated PEDI-CAT items were divided into three age groups (0-7, 8-14, and 15-21 years). Results The PEDI-CAT translation followed all six stages. The adaptations incorporated cultural and socioeconomic class specificities. The PEDI-CAT/Brazil showed good indices of inter-examiner (intraclass correlation coefficient-ICC=0.83-0.89) and test-retest (ICC=0.96-0.97) reliability, good internal consistency (0.99) and small standard error of measurement in all three age groups (0.12-0.17). Factor analyses grouped the items from the three functional skills domains into one factor, and items from the responsibility scale into three factors, supporting the adequacy of these factor solutions to the conceptual structure of the instrument and the developmental model. Conclusion The PEDI-CAT/Brazil is a theoretically consistent, culturally appropriate, and reliable instrument. Its availability in Brazil will contribute to the evaluation and measurement of functional outcomes from clinical interventions, longitudinal follow-up, and rehabilitation research. PMID:27333475

  11. Development of a Computerized Adaptive Test for Schizotypy Assessment

    PubMed Central

    Fonseca-Pedrero, Eduardo; Menéndez, Luis Fernando; Paino, Mercedes; Lemos-Giráldez, Serafín; Muñiz, José

    2013-01-01

    Background Schizotypal traits in adolescents from the general population represent the behavioral expression of liability for psychotic disorders. Schizotypy assessment in this sector of population has advanced considerably in the last few years; however, it is necessary to incorporate recent advances in psychological and educational measurement. Objective The main goal of this study was to develop a Computerized Adaptive Test (CAT) to evaluate schizotypy through “The Oviedo Questionnaire for Schizotypy Assessment” (ESQUIZO-Q), in non-clinical adolescents. Methods The final sample consisted of 3,056 participants, 1,469 males, with a mean age of 15.9 years (SD = 1.2). Results The results indicated that the ESQUIZO-Q scores presented adequate psychometric properties under both Classical Test Theory and Item Response Theory. The Information Function estimated using the Gradual Response Model indicated that the item pool effectively assesses schizotypy at the high end of the latent trait. The correlation between the CAT total scores and the paper-and-pencil test was 0.92. The mean number of presented items in the CAT with the standard error fixed at ≤0.30 was of 34 items. Conclusion The CAT showed adequate psychometric properties for schizotypy assessment in the general adolescent population. The ESQUIZO-Q adaptive version could be used as a screening method for the detection of adolescents at risk for psychosis in both educational and mental health settings. PMID:24019907

  12. Risk factors for feline immunodeficiency virus antibody test status in Cats Protection adoption centres (2004).

    PubMed

    Murray, Jane K; Roberts, Margaret A; Skillings, Elizabeth; Morrow, Lisa D; Gruffydd-Jones, Timothy J

    2009-06-01

    A study was carried out to determine the prevalence of feline immunodeficiency virus (FIV) within a population of cats entering 10 UK adoption centres run by Cats Protection. All cats entering the adoption centres during 2004 were tested for FIV using a rapid enzyme immunoassay antibody test. The overall prevalence of positive test results was 3.1% (95% confidence intervals (CI) 2.7-3.5%), whilst the prevalence at different adoption centres varied from 0.8% (95% CI 0.1-1.5%) to 6.7% (95% CI 4.9-8.5%). Results of the multivariable logistic regression analysis showed that male cats, stray/feral cats and cats in poor health were at a greater risk of testing positive for FIV than female cats, cats that were relinquished by an owner and cats that were in good/fair health, respectively. No evidence was found for an association between neuter status and FIV test results. This study may help to identify cats that are relinquished to rescue centres with an increased risk of FIV for routine FIV testing.

  13. Adaptation of IFN-gamma ELISA and ELISPOT tests for feline tuberculosis.

    PubMed

    Rhodes, Shelley G; Gruffydd-Jones, Tim; Gunn-Moore, Danièlle; Jahans, Keith

    2008-08-15

    There are currently no reliable immunodiagnostic tests for feline tuberculosis. Infection of domestic cats in the UK is thought to occur via their contact with the relevant reservoir of infection, e.g. cattle and badgers for Mycobacterium bovis, and rodents for M. microti. In the African National Parks, where M. bovis infection of Bovidae is an increasing problem, transmission to big cats is occurring via their ingestion of infected carcasses. We have adapted feline ELISA and ELISPOT assays to potentially provide the first cell-based diagnostic test for the detection of tuberculosis in cats. We tested peripheral blood mononuclear cell antigen-specific IFN-gamma responses of 18 cats suspected of mycobacterial infection for which biopsy material was co-submitted to the Veterinary Laboratories Agency for mycobacterial culture and identification. Seventeen cats were tested by ELISA while seven cats were tested by ELISPOT (six cats were tested by both ELISA and ELISPOT). Six healthy control cats provided baseline data for these tests. Responses to bovine and avian tuberculins (PPDB and PPDA) and a protein cocktail of ESAT6 and CFP10 were measured, together with positive mitogen (PMA and calcium ionophore) and negative (medium) controls. Overall, both ELISPOT and ELISA tests were found to be suitable for generating rapid results (2 and 4 days, respectively), which provided good predictive information for M. bovis and M. microti infections, but were unable to reliably discern M. avium infection.

  14. The transition of the national certification examination from paper and pencil to computer adaptive testing.

    PubMed

    Zaglaniczny, K L

    1996-02-01

    The Council on Certification of Nurse Anesthetists (CCNA) has been exploring computerized adaptive testing (CAT) for the national certification examination (NCE) over the past several years. CCNA representatives have consulted with experts in testing and with individuals from professional associations who use CAT for certification or licensure testing. This article will provide an overview of CAT and discuss how the CCNA plans to implement CAT for the NCE beginning April 8, 1996. A future article that explains the theoretical concepts of CAT will be published in the April 1996 AANA Journal. It is important to note that the NCE will not be a new test, the current content outline and item bank will remain the same. It is only the method of test administration that is changed--from paper and pencil to CAT. Each candidate will answer questions and take a test that is individualized to his or her ability or competence level and meets the specifications of the test outline. All candidates must achieve the same passing score. The implementation of CAT for the NCE will be advantageous for the candidates and provide a more efficient competency assessment. The last paper and pencil examination was administered on December 9, 1995. The transition is a significant event in nurse anesthesia history, just as nurse anesthesia was the first advanced practice nursing specialty to implement the certification credential, the CCNA will be the first to introduce CAT.

  15. An adaptive strategy for reducing Feral Cat predation on endangered hawaiian birds

    USGS Publications Warehouse

    Hess, S.C.; Banko, P.C.; Hansen, H.

    2009-01-01

    Despite the long history of Feral Cats Felis catus in Hawai'i, there has been little research to provide strategies to improve control programmes and reduce depredation on endangered species. Our objective Was to develop a predictive model to determine how landscape features on Mauna Kea, such as habitat, elevation, and proximity to roads, may affect the number of Feral Cats captured at each trap. We used log-link generalized linear models and QAIC c model ranking criteria to determine the effect of these factors. We found that The number of cats captured per trap Was related to effort, habitat type, and Whether traps Were located on The West or North Slope of Mauna Kea. We recommend an adaptive management strategy to minimize trapping interference by non-target Small Indian Mongoose Herpestes auropunctatus with toxicants, to focus trapping efforts in M??mane Sophora chrysophylla habitat on the West slope of Mauna Kea, and to cluster traps near others that have previously captured multiple cats.

  16. Design of a Computer-Adaptive Test to Measure English Literacy and Numeracy in the Singapore Workforce: Considerations, Benefits, and Implications

    ERIC Educational Resources Information Center

    Jacobsen, Jared; Ackermann, Richard; Eguez, Jane; Ganguli, Debalina; Rickard, Patricia; Taylor, Linda

    2011-01-01

    A computer adaptive test (CAT) is a delivery methodology that serves the larger goals of the assessment system in which it is embedded. A thorough analysis of the assessment system for which a CAT is being designed is critical to ensure that the delivery platform is appropriate and addresses all relevant complexities. As such, a CAT engine must be…

  17. Characterizing contrast adaptation in a population of cat primary visual cortical neurons using Fisher information.

    PubMed

    Durant, Szonya; Clifford, Colin W G; Crowder, Nathan A; Price, Nicholas S C; Ibbotson, Michael R

    2007-06-01

    When cat V1/V2 cells are adapted to contrast at their optimal orientation, a reduction in gain and/or a shift in the contrast response function is found. We investigated how these factors combine at the population level to affect the accuracy for detecting variations in contrast. Using the contrast response function parameters from a physiologically measured population, we model the population accuracy (using Fisher information) for contrast discrimination. Adaptation at 16%, 32%, and 100% contrast causes a shift in peak accuracy. Despite an overall drop in firing rate over the whole population, accuracy is enhanced around the adapted contrast and at higher contrasts, leading to greater efficiency of contrast coding at these levels. The estimated contrast discrimination threshold curve becomes elevated and shifted toward higher contrasts after adaptation, as has been found previously in human psychophysical experiments.

  18. Mission Adaptive Wing test program

    NASA Technical Reports Server (NTRS)

    Birk, Frank T.; Smith, Rogers E.

    1986-01-01

    With the completion of the F-111 test-bed Mission Adaptive Wing (MAW) test program's manual flight control system, emphasis has been shifted to flight testing of MAW automatic control modes. These encompass (1) cruise camber control, (2) maneuver camber control, (3) maneuver load control, and (4) maneuver enhancement and load alleviation control. The aircraft is currently cleared to a 2.5-g maneuvering limit due to generally higher variable-incidence wing pivot loads than had been anticipated, especially at the higher wing-camber settings. Buffet is noted to be somewhat higher than expected at the higher camber settings.

  19. EXSPRT: An Expert Systems Approach to Computer-Based Adaptive Testing.

    ERIC Educational Resources Information Center

    Frick, Theodore W.; And Others

    Expert systems can be used to aid decision making. A computerized adaptive test (CAT) is one kind of expert system, although it is not commonly recognized as such. A new approach, termed EXSPRT, was devised that combines expert systems reasoning and sequential probability ratio test stopping rules. EXSPRT-R uses random selection of test items,…

  20. The Influence of Item Calibration Error on Variable-Length Computerized Adaptive Testing

    ERIC Educational Resources Information Center

    Patton, Jeffrey M.; Cheng, Ying; Yuan, Ke-Hai; Diao, Qi

    2013-01-01

    Variable-length computerized adaptive testing (VL-CAT) allows both items and test length to be "tailored" to examinees, thereby achieving the measurement goal (e.g., scoring precision or classification) with as few items as possible. Several popular test termination rules depend on the standard error of the ability estimate, which in turn depends…

  1. An Efficiency Balanced Information Criterion for Item Selection in Computerized Adaptive Testing

    ERIC Educational Resources Information Center

    Han, Kyung T.

    2012-01-01

    Successful administration of computerized adaptive testing (CAT) programs in educational settings requires that test security and item exposure control issues be taken seriously. Developing an item selection algorithm that strikes the right balance between test precision and level of item pool utilization is the key to successful implementation…

  2. Effect of Rasch Calibration on Ability and DIF Estimation in Computer-Adaptive Tests. Research Report RR-94-32.

    ERIC Educational Resources Information Center

    Zwick, Rebecca; And Others

    A previous simulation study of methods for assessing item functioning (DIF) in computer-adaptive tests (CATs) showed that modified versions of the Mantel-Haenszel and standardization methods work well with CAT data. In that study, data were generated using the three-parameter logistic (3PL) model, and this same model was assumed in obtaining item…

  3. Developing new online calibration methods for multidimensional computerized adaptive testing.

    PubMed

    Chen, Ping; Wang, Chun; Xin, Tao; Chang, Hua-Hua

    2017-02-01

    Multidimensional computerized adaptive testing (MCAT) has received increasing attention over the past few years in educational measurement. Like all other formats of CAT, item replenishment is an essential part of MCAT for its item bank maintenance and management, which governs retiring overexposed or obsolete items over time and replacing them with new ones. Moreover, calibration precision of the new items will directly affect the estimation accuracy of examinees' ability vectors. In unidimensional CAT (UCAT) and cognitive diagnostic CAT, online calibration techniques have been developed to effectively calibrate new items. However, there has been very little discussion of online calibration in MCAT in the literature. Thus, this paper proposes new online calibration methods for MCAT based upon some popular methods used in UCAT. Three representative methods, Method A, the 'one EM cycle' method and the 'multiple EM cycles' method, are generalized to MCAT. Three simulation studies were conducted to compare the three new methods by manipulating three factors (test length, item bank design, and level of correlation between coordinate dimensions). The results showed that all the new methods were able to recover the item parameters accurately, and the adaptive online calibration designs showed some improvements compared to the random design under most conditions.

  4. The Effects of Test Difficulty Manipulation in Computerized Adaptive Testing and Self-Adapted Testing.

    ERIC Educational Resources Information Center

    Ponsoda, Vicente; Olea, Julio; Rodriguez, Maria Soledad; Revuelta, Javier

    1999-01-01

    Compared easy and difficult versions of self-adapted tests (SAT) and computerized adapted tests. No significant differences were found among the tests for estimated ability or posttest state anxiety in studies with 187 Spanish high school students, although other significant differences were found. Discusses implications for interpreting test…

  5. Practical Issues in Large-Scale High-Stakes Computerized Adaptive Testing.

    ERIC Educational Resources Information Center

    Mills, Craig N.; Stocking, Martha L.

    Computerized adaptive testing (CAT), while well-grounded in psychometric theory, has had few large-scale applications for high-stakes, secure tests in the past. This is now changing as the cost of computing has declined rapidly. As is always true where theory is translated into practice, many practical issues arise. This paper discusses a number…

  6. A Practical Computer Adaptive Testing Model for Small-Scale Scenarios

    ERIC Educational Resources Information Center

    Tao, Yu-Hui; Wu, Yu-Lung; Chang, Hsin-Yi

    2008-01-01

    Computer adaptive testing (CAT) is theoretically sound and efficient, and is commonly seen in larger testing programs. It is, however, rarely seen in a smaller-scale scenario, such as in classrooms or business daily routines, because of the complexity of most adopted Item Response Theory (IRT) models. While the Sequential Probability Ratio Test…

  7. Electronic Quality of Life Assessment Using Computer-Adaptive Testing

    PubMed Central

    2016-01-01

    Background Quality of life (QoL) questionnaires are desirable for clinical practice but can be time-consuming to administer and interpret, making their widespread adoption difficult. Objective Our aim was to assess the performance of the World Health Organization Quality of Life (WHOQOL)-100 questionnaire as four item banks to facilitate adaptive testing using simulated computer adaptive tests (CATs) for physical, psychological, social, and environmental QoL. Methods We used data from the UK WHOQOL-100 questionnaire (N=320) to calibrate item banks using item response theory, which included psychometric assessments of differential item functioning, local dependency, unidimensionality, and reliability. We simulated CATs to assess the number of items administered before prespecified levels of reliability was met. Results The item banks (40 items) all displayed good model fit (P>.01) and were unidimensional (fewer than 5% of t tests significant), reliable (Person Separation Index>.70), and free from differential item functioning (no significant analysis of variance interaction) or local dependency (residual correlations < +.20). When matched for reliability, the item banks were between 45% and 75% shorter than paper-based WHOQOL measures. Across the four domains, a high standard of reliability (alpha>.90) could be gained with a median of 9 items. Conclusions Using CAT, simulated assessments were as reliable as paper-based forms of the WHOQOL with a fraction of the number of items. These properties suggest that these item banks are suitable for computerized adaptive assessment. These item banks have the potential for international development using existing alternative language versions of the WHOQOL items. PMID:27694100

  8. Applicable Adaptive Testing Models for School Teachers.

    ERIC Educational Resources Information Center

    Wang, Albert Chang-hwa; Chuang, Chi-lin

    2002-01-01

    Describes a study conducted in Taipei (Taiwan) that investigated the attitudinal effects of SPRT (Sequential Probability Ratio Test) adaptive testing environment on junior high school students. Discusses test anxiety; student preferences; test adaptability; acceptance of test results; number of items answered; and computer experience. (Author/LRW)

  9. Adaptive Testing without a Computer.

    DTIC Science & Technology

    1981-03-01

    AO-A09? 353 AErSIARCH APPLICATIONS INC ROCKVILZI 14 P /s 5/9 ADAPTIVE TESTING WITHOUT A COMPUTER,(U) MAR 81 0 FRIEDMAN. A STEINBRG. N J RE I33615-?797...I -, IhI, III h II I I ,.-, r 11 % lll,.l ,n h . ,’l , ,, *i I.T I .- I,’ I I I ,I,, ’, I .I ,. I- Rofk %i h’ I l ,r I N ,,II I _ 2 1 W - P II11_...a., ,ol ) I ,I’l t \\I. I T1Hl.11’r . A a. SLCUi~~ AS AT ,N IF T HIS P AGE .’%h,, 0i.1. 1’ ,lli EPORT DOCUMENTATION PAGE IIEI-op INST!WAI(T)s O U R

  10. Curiosity adapted the cat: the role of trait curiosity in newcomer adaptation.

    PubMed

    Harrison, Spencer H; Sluss, David M; Ashforth, Blake E

    2011-01-01

    Using longitudinal data from 123 newcomers across 12 telemarketing organizations, we examined the role of 2 forms of trait curiosity (specific and diversive) as antecedents of proximal adaptation behaviors (information seeking and positive framing) and more distal, in-role and extra-role behaviors (job performance and taking charge). Results suggest that specific curiosity predicts information seeking behaviors, whereas diversive curiosity promotes positive framing. Results also support the relationship between positive framing and performance and the extra-role behavior of taking charge. Overall, the study validates the role of curiosity as a multifaceted individual difference that serves as an antecedent to newcomer adaptation.

  11. The Accuracy of Computerized Adaptive Testing in Heterogeneous Populations: A Mixture Item-Response Theory Analysis

    PubMed Central

    Kopec, Jacek A.; Wu, Amery D.; Zumbo, Bruno D.

    2016-01-01

    Background Computerized adaptive testing (CAT) utilizes latent variable measurement model parameters that are typically assumed to be equivalently applicable to all people. Biased latent variable scores may be obtained in samples that are heterogeneous with respect to a specified measurement model. We examined the implications of sample heterogeneity with respect to CAT-predicted patient-reported outcomes (PRO) scores for the measurement of pain. Methods A latent variable mixture modeling (LVMM) analysis was conducted using data collected from a heterogeneous sample of people in British Columbia, Canada, who were administered the 36 pain domain items of the CAT-5D-QOL. The fitted LVMM was then used to produce data for a simulation analysis. We evaluated bias by comparing the referent PRO scores of the LVMM with PRO scores predicted by a “conventional” CAT (ignoring heterogeneity) and a LVMM-based “mixture” CAT (accommodating heterogeneity). Results The LVMM analysis indicated support for three latent classes with class proportions of 0.25, 0.30 and 0.45, which suggests that the sample was heterogeneous. The simulation analyses revealed differences between the referent PRO scores and the PRO scores produced by the “conventional” CAT. The “mixture” CAT produced PRO scores that were nearly equivalent to the referent scores. Conclusion Bias in PRO scores based on latent variable models may result when population heterogeneity is ignored. Improved accuracy could be obtained by using CATs that are parameterized using LVMM. PMID:26930348

  12. Reduction in patient burdens with graphical computerized adaptive testing on the ADL scale: tool development and simulation

    PubMed Central

    Chien, Tsair-Wei; Wu, Hing-Man; Wang, Weng-Chung; Castillo, Roberto Vasquez; Chou, Willy

    2009-01-01

    Background The aim of this study was to verify the effectiveness and efficacy of saving time and reducing burden for patients, nurses, and even occupational therapists through computer adaptive testing (CAT). Methods Based on an item bank of the Barthel Index (BI) and the Frenchay Activities Index (FAI) for assessing comprehensive activities of daily living (ADL) function in stroke patients, we developed a visual basic application (VBA)-Excel CAT module, and (1) investigated whether the averaged test length via CAT is shorter than that of the traditional all-item-answered non-adaptive testing (NAT) approach through simulation, (2) illustrated the CAT multimedia on a tablet PC showing data collection and response errors of ADL clinical functional measures in stroke patients, and (3) demonstrated the quality control of endorsing scale with fit statistics to detect responding errors, which will be further immediately reconfirmed by technicians once patient ends the CAT assessment. Results The results show that endorsed items could be shorter on CAT (M = 13.42) than on NAT (M = 23) at 41.64% efficiency in test length. However, averaged ability estimations reveal insignificant differences between CAT and NAT. Conclusion This study found that mobile nursing services, placed at the bedsides of patients could, through the programmed VBA-Excel CAT module, reduce the burden to patients and save time, more so than the traditional NAT paper-and-pencil testing appraisals. PMID:19416521

  13. Computer-Adaptive Testing for Students with Disabilities: A Review of the Literature. Research Report. ETS RR-11-32

    ERIC Educational Resources Information Center

    Stone, Elizabeth; Davey, Tim

    2011-01-01

    There has been an increased interest in developing computer-adaptive testing (CAT) and multistage assessments for K-12 accountability assessments. The move to adaptive testing has been met with some resistance by those in the field of special education who express concern about routing of students with divergent profiles (e.g., some students with…

  14. A New Stopping Rule for Computerized Adaptive Testing.

    PubMed

    Choi, Seung W; Grady, Matthew W; Dodd, Barbara G

    2010-12-01

    The goal of the current study was to introduce a new stopping rule for computerized adaptive testing. The predicted standard error reduction stopping rule (PSER) uses the predictive posterior variance to determine the reduction in standard error that would result from the administration of additional items. The performance of the PSER was compared to that of the minimum standard error stopping rule and a modified version of the minimum information stopping rule in a series of simulated adaptive tests, drawn from a number of item pools. Results indicate that the PSER makes efficient use of CAT item pools, administering fewer items when predictive gains in information are small and increasing measurement precision when information is abundant.

  15. Rotationally Adaptive Flight Test Surface

    NASA Technical Reports Server (NTRS)

    Barrett, Ron

    1999-01-01

    Research on a new design of flutter exciter vane using adaptive materials was conducted. This novel design is based on all-moving aerodynamic surface technology and consists of a structurally stiff main spar, a series of piezoelectric actuator elements and an aerodynamic shell which is pivoted around the main spar. The work was built upon the current missile-type all-moving surface designs and change them so they are better suited for flutter excitation through the transonic flight regime. The first portion of research will be centered on aerodynamic and structural modeling of the system. USAF DatCom and vortex lattice codes was used to capture the fundamental aerodynamics of the vane. Finite element codes and laminated plate theory and virtual work analyses will be used to structurally model the aerodynamic vane and wing tip. Following the basic modeling, a flutter test vane was designed. Each component within the structure was designed to meet the design loads. After the design loads are met, then the deflections will be maximized and the internal structure will be laid out. In addition to the structure, a basic electrical control network will be designed which will be capable of driving a scaled exciter vane. The third and final stage of main investigation involved the fabrication of a 1/4 scale vane. This scaled vane was used to verify kinematics and structural mechanics theories on all-moving actuation. Following assembly, a series of bench tests was conducted to determine frequency response, electrical characteristics, mechanical and kinematic properties. Test results indicate peak-to-peak deflections of 1.1 deg with a corner frequency of just over 130 Hz.

  16. A Monte Carlo Simulation Investigating the Validity and Reliability of Ability Estimation in Item Response Theory with Speeded Computer Adaptive Tests

    ERIC Educational Resources Information Center

    Schmitt, T. A.; Sass, D. A.; Sullivan, J. R.; Walker, C. M.

    2010-01-01

    Imposed time limits on computer adaptive tests (CATs) can result in examinees having difficulty completing all items, thus compromising the validity and reliability of ability estimates. In this study, the effects of speededness were explored in a simulated CAT environment by varying examinee response patterns to end-of-test items. Expectedly,…

  17. Computerized Adaptive Mastery Tests as Expert Systems.

    ERIC Educational Resources Information Center

    Frick, Theodore W.

    1992-01-01

    Discussion of expert systems and computerized adaptive tests describes two versions of EXSPRT, a new approach that combines uncertain inference in expert systems with sequential probability ratio test (SPRT) stopping rules. Results of two studies comparing EXSPRT to adaptive mastery testing based on item response theory and SPRT approaches are…

  18. The Theory about CD-CAT Based on FCA and Its Application

    ERIC Educational Resources Information Center

    Shuqun, Yang; Shuliang, Ding; Zhiqiang, Yao

    2009-01-01

    Cognitive diagnosis (CD) plays an important role in intelligent tutoring system. Computerized adaptive testing (CAT) is adaptive, fair, and efficient, which is suitable to large-scale examination. Traditional cognitive diagnostic test needs quite large number of items, the efficient and tailored CAT could be a remedy for it, so the CAT with…

  19. Stratified and Maximum Information Item Selection Procedures in Computer Adaptive Testing

    ERIC Educational Resources Information Center

    Deng, Hui; Ansley, Timothy; Chang, Hua-Hua

    2010-01-01

    In this study we evaluated and compared three item selection procedures: the maximum Fisher information procedure (F), the a-stratified multistage computer adaptive testing (CAT) (STR), and a refined stratification procedure that allows more items to be selected from the high a strata and fewer items from the low a strata (USTR), along with…

  20. Optimal Item Pool Design for a Highly Constrained Computerized Adaptive Test

    ERIC Educational Resources Information Center

    He, Wei

    2010-01-01

    Item pool quality has been regarded as one important factor to help realize enhanced measurement quality for the computerized adaptive test (CAT) (e.g., Flaugher, 2000; Jensema, 1977; McBride & Wise, 1976; Reckase, 1976; 2003; van der Linden, Ariel, & Veldkamp, 2006; Veldkamp & van der Linden, 2000; Xing & Hambleton, 2004). However, studies are…

  1. The Use of Unidimensional Item Parameter Estimates of Multidimensional Items in Adaptive Testing.

    ERIC Educational Resources Information Center

    Ackerman, Terry A.

    The purpose of this study was to investigate the effect of using multidimensional items in a computer adaptive test (CAT) setting which assumes a unidimensional item response theory (IRT) framework. Previous research has suggested that the composite of multidimensional abilities being estimated by a unidimensional IRT model is not constant…

  2. The Development and Evaluation of a Software Prototype for Computer-Adaptive Testing

    ERIC Educational Resources Information Center

    Lilley, M.; Barker, T.; Britton, C.

    2004-01-01

    This paper presents ongoing research at the University of Hertfordshire on the use of computer-adaptive tests (CATs) in Higher Education. A software prototype based on Item Response Theory has been developed and is described here. This application was designed to estimate the level of proficiency in English for those students whose first language…

  3. A Simulation Study of Methods for Assessing Differential Item Functioning in Computer-Adaptive Tests.

    ERIC Educational Resources Information Center

    Zwick, Rebecca; And Others

    Simulated data were used to investigate the performance of modified versions of the Mantel-Haenszel and standardization methods of differential item functioning (DIF) analysis in computer-adaptive tests (CATs). Each "examinee" received 25 items out of a 75-item pool. A three-parameter logistic item response model was assumed, and…

  4. Effects of Calibration Sample Size and Item Bank Size on Ability Estimation in Computerized Adaptive Testing

    ERIC Educational Resources Information Center

    Sahin, Alper; Weiss, David J.

    2015-01-01

    This study aimed to investigate the effects of calibration sample size and item bank size on examinee ability estimation in computerized adaptive testing (CAT). For this purpose, a 500-item bank pre-calibrated using the three-parameter logistic model with 10,000 examinees was simulated. Calibration samples of varying sizes (150, 250, 350, 500,…

  5. Lessons Learned in Designing and Implementing a Computer-Adaptive Test for English

    ERIC Educational Resources Information Center

    Burston, Jack; Neophytou, Maro

    2014-01-01

    This paper describes the lessons learned in designing and implementing a computer-adaptive test (CAT) for English. The early identification of students with weak L2 English proficiency is of critical importance in university settings that have compulsory English language course graduation requirements. The most efficient means of diagnosing the L2…

  6. Preliminary Validation and Reliability Testing of the Montreal Instrument for Cat Arthritis Testing, for Use by Veterinarians, in a Colony of Laboratory Cats

    PubMed Central

    Klinck, Mary P.; Rialland, Pascale; Guillot, Martin; Moreau, Maxim; Frank, Diane; Troncy, Eric

    2015-01-01

    Simple Summary Feline osteoarthritis (OA) is challenging to diagnose. A pain scale was developed for use by veterinarians, in association with their physical examination, and tested for reliability and validity. The scale items were: Interaction with the examiner, Exploration of the room, Body Posture, Gait, Body Condition, condition of Coat and Claws, and abnormal Findings or Cat Reaction upon joint Palpation. Expert review supported the scale content. Two studies using laboratory-housed cats found the most promising results for Gait and Body Posture, in terms of distinguishing between OA and non-OA cats, repeatability of results, and correlations with objectively measured kinetics (weight-bearing). Abstract Subtle signs and conflicting physical and radiographic findings make feline osteoarthritis (OA) challenging to diagnose. A physical examination-based assessment was developed, consisting of eight items: Interaction, Exploration, Posture, Gait, Body Condition, Coat and Claws, (joint) Palpation–Findings, and Palpation–Cat Reaction. Content (experts) and face (veterinary students) validity were excellent. Construct validity, internal consistency, and intra- and inter-rater reliability were assessed via a pilot and main study, using laboratory-housed cats with and without OA. Gait distinguished OA status in the pilot (p = 0.05) study. In the main study, no scale item achieved statistically significant OA detection. Forelimb peak vertical ground reaction force (PVF) correlated inversely with Gait (Rhos = −0.38 (p = 0.03) to −0.41 (p = 0.02)). Body Posture correlated with Gait, and inversely with forelimb PVF at two of three time points (Rhos = −0.38 (p = 0.03) to −0.43 (p = 0.01)). Palpation (Findings, Cat Reaction) did not distinguish OA from non-OA cats. Palpation—Cat Reaction (Forelimbs) correlated inversely with forelimb PVF at two time points (Rhos = −0.41 (p = 0.02) to −0.41 (p = 0.01)), but scores were highly variable, and poorly reliable

  7. Comparison of different in-house test systems to detect parvovirus in faeces of cats.

    PubMed

    Neuerer, Felix F; Horlacher, Karin; Truyen, Uwe; Hartmann, Katrin

    2008-07-01

    In-house tests for the identification of faecal parvovirus antigen are now available. The majority of these are licensed for canine parvovirus only; but anecdotal information suggests that they will detect feline panleukopenia virus (FPV) as well. This prospective study was designed to compare five commercially available test systems. In total, 200 faecal samples from randomly selected healthy cats (148) and cats with diarrhoea (52) were tested and compared with the results of examination by electron microscopy. Ten cats were positive for FPV and all of these had diarrhoea. In-house canine parvovirus tests can be used to detect FPV. All tests were suitable to screen cats for faecal parvovirus excretion (positive predictive values for the Witness Parvo, the Snap Parvo, the SAS Parvo, the Fastest Parvo Strip, and the Speed Parvo were 100.0, 100.0, 57.1, 38.9, and 100%, respectively, negative predictive values for the Witness Parvo, the Snap Parvo, the SAS Parvo, the Fastest Parvo Strip, and the Speed Parvo were 97.4, 97.9, 98.9, 98.4, and 97.4%, respectively). In-house parvovirus tests may be positive up to 2 weeks after vaccination, and therefore, in recently vaccinated cats positive results do not necessarily mean infection.

  8. Flexilevel Adaptive Testing Paradigm: Hierarchical Concept Structures.

    DTIC Science & Technology

    1977-07-01

    items . In reference to the psychometric outcomes, Table 3 presents the mean item difficulties by subtest plus a Kuder - Richardson reliability index. A...leas~: 50percent of the subject population , an adaptive Kuder - Richardson index was calculated . This was found to be r = . 701 for Block II test and r...whole correlations between adaptive test and total test scores (r ’s = .95). Descriptive test indices and test reliabilities were also essentially

  9. Item Selection in Computerized Adaptive Testing: Improving the a-Stratified Design with the Sympson-Hetter Algorithm

    ERIC Educational Resources Information Center

    Leung, Chi-Keung; Chang, Hua-Hua; Hau, Kit-Tai

    2002-01-01

    Item exposure control, test-overlap minimization, and the efficient use of item pool are some of the important issues in computerized adaptive testing (CAT) designs. The overexposure of some items and high test-overlap rate may cause both item and test security problems. Previously these problems associated with the maximum information (Max-I)…

  10. Flight Test Approach to Adaptive Control Research

    NASA Technical Reports Server (NTRS)

    Pavlock, Kate Maureen; Less, James L.; Larson, David Nils

    2011-01-01

    The National Aeronautics and Space Administration s Dryden Flight Research Center completed flight testing of adaptive controls research on a full-scale F-18 testbed. The validation of adaptive controls has the potential to enhance safety in the presence of adverse conditions such as structural damage or control surface failures. This paper describes the research interface architecture, risk mitigations, flight test approach and lessons learned of adaptive controls research.

  11. [Abnormal behavior and adaptation problems in dogs and cats and their pharmacologic control].

    PubMed

    Jöchle, W

    1998-11-01

    Small animal practitioners are increasingly confronted with patients showing adaptation related problems (ARP) which are expressed as disturbed or abnormal behavior (DAB). As a result, practitioners are asked increasingly to euthanize animals which seemingly cannot be socialized. In healthy dogs and cats, three main causes for DAB can be detected: refusal of obedience because of the drive for dominance; anxiety and frustration; and geriatric DAB. Increasingly, disease conditions not readily diagnosed can cause DAB, especially hypothyroidism. Influencing and contributing factors to DAB are breed, sex, experiences as a puppy, behavior of owners, changes in the pet's environment. ARPs may also cause disturbances in the condition of skin and fur, e.g. atopic dermatitis, pruritus sine materia, lick granuloma, and of the intestinal organs (vomiting, irritated bowel syndrome) and may result in an immune deficiency. Therapeutic approaches include behavioral therapy, surgical or hormonal castration with progestins or antiandrogens, substitution with thyroxin in cases with hypothyroidism, and/or the use of psychopharmaca, most prominently of modern antidepressiva like amitriptyline; buspirone; clomipramine and fluoxetine, but also of selegiline, a mono-aminoxydase inhibitor. These compounds, among other effects, are elevating prolactin levels. This seems to allow to formulate a working hypothesis: in the canine species, prolactin is obviously a hormone enabling socialization; hence all drugs which safely cause an increase in prolactin production might be suitable to manage or control ARPs and DAB in the dog, but also in the cat. Higher levels of prolactin than those required for socialization, as seen in nursing bitches or some clinically overt cases of pseudopregnancy, may cause maternal aggression and can be controlled with prolactin inhibitors, if needed.

  12. A Model for Optimal Constrained Adaptive Testing.

    ERIC Educational Resources Information Center

    van der Linden, Wim J.; Reese, Lynda M.

    1998-01-01

    Proposes a model for constrained computerized adaptive testing in which the information in the test at the trait level (theta) estimate is maximized subject to the number of possible constraints on the content of the test. Test assembly relies on a linear-programming approach. Illustrates the approach through simulation with items from the Law…

  13. The Stratified Adaptive Computerized Ability Test.

    ERIC Educational Resources Information Center

    Weiss, David J.

    This report describes the stratified adaptive (stradaptive) test as a strategy for tailoring an ability test to individual differences in testee ability; administration of the test is controlled by a time-shared computer system. The rationale of this method is described as it derives from Binet's strategy of ability test administration and…

  14. Test Target for Adaptive Optics.

    DTIC Science & Technology

    adaptive optics comprising, in the preferred embodiment, a plurality of nine adjacent, stacked, and aligned rows of a multiplicity of alternate opaque sections and transparent sections in a repeating bar pattern, with all sections being positioned on a flat transparent medium (such as film or glass), and with each opaque section being an opaque bar and with each transparent section being a transparent bar. Each row has a different spatial frequency than any other of the nine rows, with the spatial frequency of any one row being of a different multiple of the row having the

  15. Bayesian Item Selection in Constrained Adaptive Testing Using Shadow Tests

    ERIC Educational Resources Information Center

    Veldkamp, Bernard P.

    2010-01-01

    Application of Bayesian item selection criteria in computerized adaptive testing might result in improvement of bias and MSE of the ability estimates. The question remains how to apply Bayesian item selection criteria in the context of constrained adaptive testing, where large numbers of specifications have to be taken into account in the item…

  16. Graphical Models and Computerized Adaptive Testing.

    ERIC Educational Resources Information Center

    Almond, Russell G.; Mislevy, Robert J.

    1999-01-01

    Considers computerized adaptive testing from the perspective of graphical modeling (GM). GM provides methods for making inferences about multifaceted skills and knowledge and for extracting data from complex performances. Provides examples from language-proficiency assessment. (SLD)

  17. Adaptive structures - Test hardware and experimental results

    NASA Technical Reports Server (NTRS)

    Wada, Ben K.; Fanson, James L.; Chen, Gun-Shing; Kuo, Chin-Po

    1990-01-01

    The facilities and procedures used at JPL to test adaptive structures such as the large deployable reflector (LDR) are described and preliminary results are reported. The applications of adaptive structures in future NASA missions are outlined, and the techniques which are employed to modify damping, stiffness, and isolation characteristics, as well as geometric changes, are listed. The development of adaptive structures is shown to be effective as a result of new actuators and sensors, and examples are listed for categories such as fiber optics, shape-memory materials, piezoelectrics, and electrorheological fluids. Some ground test results are described for laboratory truss structures and truss test beds, which are shown to be efficient and easy to assemble in space. Adaptive structures are shown to be important for precision space structures such as the LDR, and can alleviate ground test requirements.

  18. National Tests in Denmark--CAT as a Pedagogic Tool

    ERIC Educational Resources Information Center

    Wandall, Jakob

    2011-01-01

    Testing and test results can be used in different ways. They can be used for regulation and control, but they can also be a pedagogic tool for assessment of student proficiency in order to target teaching, improve learning and facilitate local pedagogical leadership. To serve these purposes the test has to be used for low stakes purposes, and to…

  19. GENE EXPRESSION IN THE TESTES OF NORMOSPERMIC VERSUS TERATOSPERMIC DOMESTIC CATS USING HUMAN CDNA MICROARRAY ANALYSES

    EPA Science Inventory

    GENE EXPRESSION IN THE TESTES OF NORMOSPERMIC VERSUS TERATOSPERMIC DOMESTIC CATS USING HUMAN cDNA MICROARRAY ANALYSES

    B.S. Pukazhenthi1, J. C. Rockett2, M. Ouyang3, D.J. Dix2, J.G. Howard1, P. Georgopoulos4, W.J. J. Welsh3 and D. E. Wildt1

    1Department of Reproductiv...

  20. Evaluation Parameters for Computer-Adaptive Testing

    ERIC Educational Resources Information Center

    Georgiadou, Elisabeth; Triantafillou, Evangelos; Economides, Anastasios A.

    2006-01-01

    With the proliferation of computers in test delivery today, adaptive testing has become quite popular, especially when examinees must be classified into two categories (passfail, master nonmaster). Several well-established organisations have provided standards and guidelines for the design and evaluation of educational and psychological testing.…

  1. Computer Adaptive Testing: A New Era.

    ERIC Educational Resources Information Center

    Smittle, Pat

    1993-01-01

    Describes a study to determine whether traditional paper-and-pencil tests or new computer-adaptive tests were better suited for assessing entering students at Santa Fe Community College, Florida. Focuses on teachers' attitudes toward computerized placement tests (CPTs), relationships between CPT scores and course grades, predictive ability of CPT…

  2. Strategies for Computerized Adaptive Grading Testing.

    ERIC Educational Resources Information Center

    Xiao, Beiling

    1999-01-01

    Evaluated three strategies for assigning examinees to grading categories in computerized adaptive testing. The expected a posteriori-based method had more correct classifications in the middle range of grade levels and more errors for the extremes than the golden section search grading test and the Z-score grading test. (SLD)

  3. Dichotomous Search Strategies for Computerized Adaptive Testing.

    ERIC Educational Resources Information Center

    Xiao, Beiling

    Dichotomous search strategies (DSSs) for computerized adaptive testing are similar to golden section search strategies (GSSSs). Each middle point of successive search regions is a testing point. After each item is administered, the subject's obtained score is compared with the expected score at successive testing points. If the subject's obtained…

  4. Computerized Adaptive Testing in Reading.

    ERIC Educational Resources Information Center

    Smittle, Pat

    1991-01-01

    Discusses the use of computerized placement testing at Santa Fe Community College to enable students needing only a short review of reading skills to exit early from a College Preparatory Reading Class (CPRC). Describes CPRC placement, structure, curriculum, and exit criteria; the Early Exit Reading Project; and project results. (DMM)

  5. An Empirical Bayes Enhancement of Mantel-Haenszel DIF Analysis for Computer-Adaptive Tests. LSAC Research Report Series.

    ERIC Educational Resources Information Center

    Zwick, Rebecca; Thayer, Dorothy T.

    This study investigated the applicability to computerized adaptive testing (CAT) data of a differential item functioning (DIF) analysis that involves an empirical Bayes (EB) enhancement of the popular Mantel Haenszel (MH) DIF analysis method. The computerized Law School Admission Test (LSAT) assumed for this study was similar to that currently…

  6. Computerized Adaptive Testing with Item Cloning.

    ERIC Educational Resources Information Center

    Glas, Cees A. W.; van der Linden, Wim J.

    2003-01-01

    Developed a multilevel item response (IRT) model that allows for differences between the distributions of item parameters of families of item clones. Results from simulation studies based on an item pool from the Law School Admission Test illustrate the accuracy of the item pool calibration and adaptive testing procedures based on the model. (SLD)

  7. Conical isogrid adapter structural test results

    NASA Technical Reports Server (NTRS)

    Dyer, J. E.; Slysh, P.

    1974-01-01

    The structural characteristics of isogrid composite structures are discussed. To demonstrate the feasibility of applying isogrid to conical structures, a full scale flanged isogrid conical adapter similar to the configuration of the D-1 Centaur equipment module was constructed. The adapter was tested to evaluate the response of the conical isogrid structure to various combinations of bending and axial compression loading. The analysis techniques for predicting conical isogrid structural capability are examined.

  8. Serological, intradermal and live flea challenge tests in the assessment of hypersensitivity to flea antigens in cats (Felis domesticus).

    PubMed

    Bond, Ross; Hutchinson, Melanie J; Loeffler, Anette

    2006-09-01

    The results of intradermal testing with three commercial flea antigens and a serological test for IgE antibodies to flea antigens were compared with live flea challenge in cats. Eight control cats with no prior flea exposure had negative serological test and flea challenge results. By contrast, 17 out of 27 cats with previous flea exposure showed immediate reactivity to flea challenge; reactivity at 6, 24 and 48 h after flea exposure was noted in 12, 16 and 21 cats, respectively. Seventeen of these cats had positive serological test results. Seven cats showed immediate intradermal test reactions to the ARTU allergen, six reacted to the Biophady allergen, and six reacted to the Greer allergen. Intradermal test reactivity was less frequent at the other time points. Using the results of the flea challenge as the 'gold standard' for the presence or absence of sensitisation to fleas, the sensitivity and specificity of the serological test was 0.88 and 0.77, respectively. Sensitivities of the intradermal tests at the four time points ranged from 0 to 0.33, whereas the specificities ranged from 0.78 to 1.0. Live flea challenge is better able to detect cats with hypersensitivity to fleas than either intradermal or serological testing.

  9. Conceptualising computerized adaptive testing for measurement of latent variables associated with physical objects

    NASA Astrophysics Data System (ADS)

    Camargo, F. R.; Henson, B.

    2015-02-01

    The notion of that more or less of a physical feature affects in different degrees the users' impression with regard to an underlying attribute of a product has frequently been applied in affective engineering. However, those attributes exist only as a premise that cannot directly be measured and, therefore, inferences based on their assessment are error-prone. To establish and improve measurement of latent attributes it is presented in this paper the concept of a stochastic framework using the Rasch model for a wide range of independent variables referred to as an item bank. Based on an item bank, computerized adaptive testing (CAT) can be developed. A CAT system can converge into a sequence of items bracketing to convey information at a user's particular endorsement level. It is through item banking and CAT that the financial benefits of using the Rasch model in affective engineering can be realised.

  10. Adaptive interpretation of gas well deliverability tests

    NASA Astrophysics Data System (ADS)

    Sergeev, V. L.; Thac Hoai Phuong, Nguyen; Strelnikova, A. B.

    2016-09-01

    The paper considers topical issues of improving accuracy of data obtained from gas well deliverability tests, decreasing the number of test stages and well test time, and reducing gas emissions. The aim of the research is to develop the method of adaptive interpretation of gas well deliverability tests with resulting IPR curve conducted in gas wells with steady-state filtration, which allows obtaining and taking into account additional a priori data on the formation pressure and flow coefficients, setting the number of test stages adequate for efficient well testing and reducing test time. The present research is based on the previous theoretical and practical findings in the spheres of gas well deliverability tests, systems analysis, system identification, function optimization and linear algebra. To test the method, the authors used the field data of deliverability tests run in the Urengoy gas and condensate field, Tyumen Oblast. The authors suggest the method of adaptive interpretation of gas well deliverability tests with resulting IPR curve, which is based on the law for gas filtration with variables dependent on the number of test stage and account of additional a priori data. The suggested method allows defining the estimates of the formation pressure and flow coefficients, optimal in terms of preassigned measures of quality, and setting the adequate number of test stages in the course of well testing. The case study of IPR curve data processing has indicated that adaptive interpretation provides more accurate estimates on the formation pressure and flow coefficients, as well as reduces the number of test stages.

  11. Applying Computerized Adaptive Testing to the Negative Acts Questionnaire-Revised: Rasch Analysis of Workplace Bullying

    PubMed Central

    Ma, Shu-Ching; Li, Yu-Chi; Yui, Mei-Shu

    2014-01-01

    Background Workplace bullying is a prevalent problem in contemporary work places that has adverse effects on both the victims of bullying and organizations. With the rapid development of computer technology in recent years, there is an urgent need to prove whether item response theory–based computerized adaptive testing (CAT) can be applied to measure exposure to workplace bullying. Objective The purpose of this study was to evaluate the relative efficiency and measurement precision of a CAT-based test for hospital nurses compared to traditional nonadaptive testing (NAT). Under the preliminary conditions of a single domain derived from the scale, a CAT module bullying scale model with polytomously scored items is provided as an example for evaluation purposes. Methods A total of 300 nurses were recruited and responded to the 22-item Negative Acts Questionnaire-Revised (NAQ-R). All NAT (or CAT-selected) items were calibrated with the Rasch rating scale model and all respondents were randomly selected for a comparison of the advantages of CAT and NAT in efficiency and precision by paired t tests and the area under the receiver operating characteristic curve (AUROC). Results The NAQ-R is a unidimensional construct that can be applied to measure exposure to workplace bullying through CAT-based administration. Nursing measures derived from both tests (CAT and NAT) were highly correlated (r=.97) and their measurement precisions were not statistically different (P=.49) as expected. CAT required fewer items than NAT (an efficiency gain of 32%), suggesting a reduced burden for respondents. There were significant differences in work tenure between the 2 groups (bullied and nonbullied) at a cutoff point of 6 years at 1 worksite. An AUROC of 0.75 (95% CI 0.68-0.79) with logits greater than –4.2 (or >30 in summation) was defined as being highly likely bullied in a workplace. Conclusions With CAT-based administration of the NAQ-R for nurses, their burden was substantially

  12. Responses of slowly adapting type II afferent fibres in cat hairy skin to vibrotactile stimuli.

    PubMed Central

    Gynther, B D; Vickery, R M; Rowe, M J

    1992-01-01

    1. Slowly adapting type II (SAII) afferent fibres that supply the forelimb were isolated from the medial cutaneous nerve of anaesthetized cats and examined for their capacity to signal information about vibrotactile events in the hairy skin. 2. The SAII fibres had a single spot-like receptive field focus where they were highly sensitive to steady indentation and vibration applied with probes normal to the skin surface. However, their sensitivity was affected profoundly by the size of the stimulus probe, its position in relation to the receptive field focus and, to a lesser extent, the magnitude of any pre-indentation on which vibration was superimposed. Small stimulus probes (e.g. 250 microns diameter) were much more effective than larger (> or = 1-2 mm) ones, and small shifts in the position of the perpendicularly applied probe away from the receptive field focus led to a marked decline in responsiveness. 3. With appropriate choice of stimulus parameters for vibratory stimuli applied at the receptive field focus, the SAII fibres could respond at low threshold (< 100 microns), with a tightly phase-locked, regular 1:1 impulse pattern (one impulse per vibration cycle) that accurately signalled the vibration frequency over a bandwidth that extended to 600 Hz. Furthermore, their responses remained phase-locked up to 1000 Hz. Phase-locking in SAII fibres was marginally tighter than that in SAI fibres and comparable to that of Pacinian corpuscle fibres. 4. The sensitivity of forelimb SAII fibres to tangential skin stretch was directionally selective; stretch across the forelimb was much more effective than along its long axis. Vibration associated with tangential skin stretch led to a marked spatial expansion of the field of vibration sensitivity. SAII fibres could therefore signal information about natural stimuli that contain elements of skin stretch and vibration, as may be encountered when the forelimb brushes against textured surfaces. Should the SAII fibres fail to

  13. Testlet-Based Multidimensional Adaptive Testing.

    PubMed

    Frey, Andreas; Seitz, Nicki-Nils; Brandt, Steffen

    2016-01-01

    Multidimensional adaptive testing (MAT) is a highly efficient method for the simultaneous measurement of several latent traits. Currently, no psychometrically sound approach is available for the use of MAT in testlet-based tests. Testlets are sets of items sharing a common stimulus such as a graph or a text. They are frequently used in large operational testing programs like TOEFL, PISA, PIRLS, or NAEP. To make MAT accessible for such testing programs, we present a novel combination of MAT with a multidimensional generalization of the random effects testlet model (MAT-MTIRT). MAT-MTIRT compared to non-adaptive testing is examined for several combinations of testlet effect variances (0.0, 0.5, 1.0, and 1.5) and testlet sizes (3, 6, and 9 items) with a simulation study considering three ability dimensions with simple loading structure. MAT-MTIRT outperformed non-adaptive testing regarding the measurement precision of the ability estimates. Further, the measurement precision decreased when testlet effect variances and testlet sizes increased. The suggested combination of the MTIRT model therefore provides a solution to the substantial problems of testlet-based tests while keeping the length of the test within an acceptable range.

  14. Testlet-Based Multidimensional Adaptive Testing

    PubMed Central

    Frey, Andreas; Seitz, Nicki-Nils; Brandt, Steffen

    2016-01-01

    Multidimensional adaptive testing (MAT) is a highly efficient method for the simultaneous measurement of several latent traits. Currently, no psychometrically sound approach is available for the use of MAT in testlet-based tests. Testlets are sets of items sharing a common stimulus such as a graph or a text. They are frequently used in large operational testing programs like TOEFL, PISA, PIRLS, or NAEP. To make MAT accessible for such testing programs, we present a novel combination of MAT with a multidimensional generalization of the random effects testlet model (MAT-MTIRT). MAT-MTIRT compared to non-adaptive testing is examined for several combinations of testlet effect variances (0.0, 0.5, 1.0, and 1.5) and testlet sizes (3, 6, and 9 items) with a simulation study considering three ability dimensions with simple loading structure. MAT-MTIRT outperformed non-adaptive testing regarding the measurement precision of the ability estimates. Further, the measurement precision decreased when testlet effect variances and testlet sizes increased. The suggested combination of the MTIRT model therefore provides a solution to the substantial problems of testlet-based tests while keeping the length of the test within an acceptable range. PMID:27917132

  15. A Consideration for Variable Length Adaptive Tests.

    ERIC Educational Resources Information Center

    Wingersky, Marilyn S.

    In a variable-length adaptive test with a stopping rule that relied on the asymptotic standard error of measurement of the examinee's estimated true score, M. S. Stocking (1987) discovered that it was sufficient to know the examinee's true score and the number of items administered to predict with some accuracy whether an examinee's true score was…

  16. A Comparison of Four Item-Selection Methods for Severely Constrained CATs

    ERIC Educational Resources Information Center

    He, Wei; Diao, Qi; Hauser, Carl

    2013-01-01

    This study compares the four existing procedures handling the item selection in severely constrained computerized adaptive tests (CAT). These procedures include weighted deviation model (WDM), weighted penalty model (WPM), maximum priority index (MPI), and shadow test approach (STA). Severely constrained CAT refer to those adaptive tests seeking…

  17. Improving Inpatient Surveys: Web-Based Computer Adaptive Testing Accessed via Mobile Phone QR Codes

    PubMed Central

    2016-01-01

    Background The National Health Service (NHS) 70-item inpatient questionnaire surveys inpatients on their perceptions of their hospitalization experience. However, it imposes more burden on the patient than other similar surveys. The literature shows that computerized adaptive testing (CAT) based on item response theory can help shorten the item length of a questionnaire without compromising its precision. Objective Our aim was to investigate whether CAT can be (1) efficient with item reduction and (2) used with quick response (QR) codes scanned by mobile phones. Methods After downloading the 2008 inpatient survey data from the Picker Institute Europe website and analyzing the difficulties of this 70-item questionnaire, we used an author-made Excel program using the Rasch partial credit model to simulate 1000 patients’ true scores followed by a standard normal distribution. The CAT was compared to two other scenarios of answering all items (AAI) and the randomized selection method (RSM), as we investigated item length (efficiency) and measurement accuracy. The author-made Web-based CAT program for gathering patient feedback was effectively accessed from mobile phones by scanning the QR code. Results We found that the CAT can be more efficient for patients answering questions (ie, fewer items to respond to) than either AAI or RSM without compromising its measurement accuracy. A Web-based CAT inpatient survey accessed by scanning a QR code on a mobile phone was viable for gathering inpatient satisfaction responses. Conclusions With advances in technology, patients can now be offered alternatives for providing feedback about hospitalization satisfaction. This Web-based CAT is a possible option in health care settings for reducing the number of survey items, as well as offering an innovative QR code access. PMID:26935793

  18. Improving Cognitive Diagnostic Computerized Adaptive Testing by Balancing Attribute Coverage: The Modified Maximum Global Discrimination Index Method

    ERIC Educational Resources Information Center

    Cheng, Ying

    2010-01-01

    This article proposes a new item selection method, namely, the modified maximum global discrimination index (MMGDI) method, for cognitive diagnostic computerized adaptive testing (CD-CAT). The new method captures two aspects of the appeal of an item: (a) the amount of contribution it can make toward adequate coverage of every attribute and (b) the…

  19. Content Range and Precision of a Computer Adaptive Test of Upper Extremity Function for Children with Cerebral Palsy

    ERIC Educational Resources Information Center

    Montpetit, Kathleen; Haley, Stephen; Bilodeau, Nathalie; Ni, Pengsheng; Tian, Feng; Gorton, George, III; Mulcahey, M. J.

    2011-01-01

    This article reports on the content range and measurement precision of an upper extremity (UE) computer adaptive testing (CAT) platform of physical function in children with cerebral palsy. Upper extremity items representing skills of all abilities were administered to 305 parents. These responses were compared with two traditional standardized…

  20. Construct Validity and Measurement Invariance of Computerized Adaptive Testing: Application to Measures of Academic Progress (MAP) Using Confirmatory Factor Analysis

    ERIC Educational Resources Information Center

    Wang, Shudong; McCall, Marty; Jiao, Hong; Harris, Gregg

    2012-01-01

    The purposes of this study are twofold. First, to investigate the construct or factorial structure of a set of Reading and Mathematics computerized adaptive tests (CAT), "Measures of Academic Progress" (MAP), given in different states at different grades and academic terms. The second purpose is to investigate the invariance of test…

  1. Optimizing CAT-ASVAB Item Selection Using Form Assembly Techniques

    DTIC Science & Technology

    2006-06-01

    Other tests that use a CAT include the GRE [e.g., Syvum 2006] and GMAT [e.g., Princeton Review 2006]. The CAT estimates an examinee’s ability...correspondence, September 2005. The Princeton Review, 2006, GMAT : A Computer-Adaptive Test, http://www.princetonreview.com, 19, May 2006, New York, NY. Sands

  2. Applying Computerized Adaptive Testing to the Four-Dimensional Symptom Questionnaire (4DSQ): A Simulation Study

    PubMed Central

    de Beurs, Derek P; Terluin, Berend; Verhaak, Peter F

    2017-01-01

    Background Efficient screening questionnaires are useful in general practice. Computerized adaptive testing (CAT) is a method to improve the efficiency of questionnaires, as only the items that are particularly informative for a certain responder are dynamically selected. Objective The objective of this study was to test whether CAT could improve the efficiency of the Four-Dimensional Symptom Questionnaire (4DSQ), a frequently used self-report questionnaire designed to assess common psychosocial problems in general practice. Methods A simulation study was conducted using a sample of Dutch patients visiting a general practitioner (GP) with psychological problems (n=379). Responders completed a paper-and-pencil version of the 50-item 4DSQ and a psychometric evaluation was performed to check if the data agreed with item response theory (IRT) assumptions. Next, a CAT simulation was performed for each of the four 4DSQ scales (distress, depression, anxiety, and somatization), based on the given responses as if they had been collected through CAT. The following two stopping rules were applied for the administration of items: (1) stop if measurement precision is below a predefined level, or (2) stop if more than half of the items of the subscale are administered. Results In general, the items of each of the four scales agreed with IRT assumptions. Application of the first stopping rule reduced the length of the questionnaire by 38% (from 50 to 31 items on average). When the second stopping rule was also applied, the total number of items could be reduced by 56% (from 50 to 22 items on average). Conclusions CAT seems useful for improving the efficiency of the 4DSQ by 56% without losing a considerable amount of measurement precision. The CAT version of the 4DSQ may be useful as part of an online assessment to investigate the severity of mental health problems of patients visiting a GP. This simulation study is the first step needed for the development a CAT version of the 4

  3. Adapting the Critical Thinking Assessment Test for Palestinian Universities

    ERIC Educational Resources Information Center

    Basha, Sami; Drane, Denise; Light, Gregory

    2016-01-01

    Critical thinking is a key learning outcome for Palestinian students. However, there are no validated critical thinking tests in Arabic. Suitability of the US developed Critical Thinking Assessment Test (CAT) for use in Palestine was assessed. The test was piloted with university students in English (n = 30) and 4 questions were piloted in Arabic…

  4. Online Calibration Methods for the DINA Model with Independent Attributes in CD-CAT

    ERIC Educational Resources Information Center

    Chen, Ping; Xin, Tao; Wang, Chun; Chang, Hua-Hua

    2012-01-01

    Item replenishing is essential for item bank maintenance in cognitive diagnostic computerized adaptive testing (CD-CAT). In regular CAT, online calibration is commonly used to calibrate the new items continuously. However, until now no reference has publicly become available about online calibration for CD-CAT. Thus, this study investigates the…

  5. Adaptation of healthy adult cats to select dietary fibers in vivo affects gas and short-chain fatty acid production from fiber fermentation in vitro.

    PubMed

    Barry, K A; Wojcicki, B J; Bauer, L L; Middelbos, I S; Vester Boler, B M; Swanson, K S; Fahey, G C

    2011-10-01

    Nine young adult (1.73 ± 0.03 yr) male cats were used to determine the effects of microbial adaptation to select dietary fiber sources on changes in pH in vitro and on total and hydrogen gas, short-chain fatty acid (SCFA), and branched-chain fatty acid (BCFA) production. Cats were adapted to diets containing 4% cellulose, fructooligosaccharides (FOS), or pectin for 30 d before fecal sampling. Each cat was used as a single donor, and fecal inoculum was reacted with each of the aforementioned fiber substrates. Adaptation to dietary FOS resulted in a greater change in pH when exposed to FOS than pectin (adaptation × substrate, P < 0.001). When exposed to the FOS substrate, adaptation to dietary FOS or pectin increased hydrogen gas production (adaptation × substrate, P = 0.021). Adaptation to dietary FOS increased acetate and total SCFA production when exposed to FOS substrate in vitro (adaptation × substrate, P = 0.001). When exposed to the FOS substrate, propionate production tended to increase with adaptation to dietary cellulose (adaptation × substrate, P = 0.060). The BCFA + valerate tended to decrease with adaptation to dietary FOS when exposed to FOS substrate in vitro (adaptation × substrate, P = 0.092). Fructooligosaccharides resulted in the greatest change in pH and production of total gas (P < 0.001), hydrogen gas (P < 0.001), acetate (P < 0.001), propionate (P < 0.001), butyrate (P < 0.001), total SCFA (P < 0.001), and total BCFA + valerate production (P < 0.001). Adaptation to the FOS or pectin diet increased production of hydrogen gas with FOS and pectin substrates. Adaptation to pectin increased (P = 0.033) total gas production with FOS and pectin substrates. Overall, adaptation to either FOS or pectin led to greater SCFA and gas production, but adaptation to FOS resulted in the greatest effect overall.

  6. The ESO Adaptive Optics Facility under Test

    NASA Astrophysics Data System (ADS)

    Arsenault, Robin; Madec, Pierre-Yves; Paufique, Jerome; La Penna, Paolo; Stroebele, Stefan; Vernet, Elise; Pirard, Jean-François; Hackenberg, Wolfgang; Kuntschner, Harald; Kolb, Johann; Muller, Nicolas; Le Louarn, Miska; Amico, Paola; Hubin, Norbert; Lizon, Jean-Louis; Ridings, Rob; Abad, Jose; Fischer, Gert; Heinz, Volker; Kiekebusch, Mario; Argomedo, Javier; Conzelmann, Ralf; Tordo, Sebastien; Donaldson, Rob; Soenke, Christian; Duhoux, Philippe; Fedrigo, Enrico; Delabre, Bernard; Jost, Andrea; Duchateau, Michel; Downing, Mark; Moreno, Javier; Manescau, Antonio; Bonaccini Calia, Domenico; Quattri, Marco; Dupuy, Christophe; Guidolin, Ivan; Comin, Mauro; Guzman, Ronald; Buzzoni, Bernard; Quentin, Jutta; Lewis, Steffan; Jolley, Paul; Kraus, Max; Pfrommer, Thomas; Garcia-Rissmann, Aurea; Biasi, Roberto; Gallieni, Daniele; Stuik, Remko

    2013-12-01

    The Adaptive Optics Facility project has received most of its subsystems in Garching and the ESO Integration Hall has become the central operation location for the next phase of the project. The main test bench ASSIST and the 2nd Generation M2-Unit (hosting the Deformable Secondary Mirror) have been granted acceptance late 2012. The DSM will now undergo a series of tests on ASSIST to qualify its optical performance which launches the System Test Phase of the AOF. The tests will validate the AO modules operation with the DSM: first the GRAAL adaptive optics module for Hawk-I in natural guide star AO mode on-axis and then its Ground Layer AO mode. This will be followed by the GALACSI (for MUSE) Wide-Field-Mode (GLAO) and then the more challenging Narrow-Field-Mode (LTAO). We will report on the status of the subsystems at the time of the conference but also on the performance of the delivered ASSIST test bench, the DSM and the 20 Watt Sodium fiber Laser pre-production unit which has validated all specifications before final manufacturing of the serial units. We will also present some considerations and tools to ensure an efficient operation of the Facility in Paranal.

  7. Development of the cat-owner relationship scale (CORS).

    PubMed

    Howell, Tiffani J; Bowen, Jonathan; Fatjó, Jaume; Calvo, Paula; Holloway, Anna; Bennett, Pauleen C

    2017-03-07

    Characteristics of the human-animal bond can be influenced by both owner-related and pet-related factors, which likely differ between species. Three studies adapted the Monash Dog-Owner Relationship Scale (MDORS) to permit assessment of human-cat interactions as perceived by the cat's owner. In Study 1293 female cat owners completed a modified version of the MDORS, where 'dog' was replaced with 'cat' for all items. Responses were compared with a matched sample of female dog owners. A partial least squares discriminant analysis revealed systematic differences between cat and dog owners in the Dog (Cat)-Owner Interaction subscale (MDORS subscale 1), but not for Perceived Emotional Closeness or Perceived Costs (Subscales 2 and 3). Study 2 involved analysis of free-text descriptions of cat-owner interactions provided by 61 female cat owners. Text mining identified key words which were used to create additional questions for a new Cat-Owner Interaction subscale. In Study 3, the resulting cat-owner relationship scale (CORS) was tested in a group of 570 cat owners. The main psychometric properties of the scale, including internal consistency and factor structure, were evaluated. We propose that this scale can be used to accurately assess owner perceptions of their relationship with their cat. A modified scale, combining items from the CORS and MDORS (a C/DORS), is also provided for when researchers would find it desirable to compare human-cat and human-dog interactions.

  8. Adaptive testing for psychological assessment: how many items are enough to run an adaptive testing algorithm?

    PubMed

    Wagner-Menghin, Michaela M; Masters, Geoff N

    2013-01-01

    Although the principles of adaptive testing were established in the psychometric literature many years ago (e.g., Weiss, 1977), and practice of adaptive testing is established in educational assessment, it not yet widespread in psychological assessment. One obstacle to adaptive psychological testing is a lack of clarity about the necessary number of items to run an adaptive algorithm. The study explores the relationship between item bank size, test length and measurement precision. Simulated adaptive test runs (allowing a maximum of 30 items per person) out of an item bank with 10 items per ability level (covering .5 logits, 150 items total) yield a standard error of measurement (SEM) of .47 (.39) after an average of 20 (29) items for 85-93% (64-82%) of the simulated rectangular sample. Expanding the bank to 20 items per level (300 items total) did not improve the algorithm's performance significantly. With a small item bank (5 items per ability level, 75 items total) it is possible to reach the same SEM as with a conventional test, but with fewer items or a better SEM with the same number of items.

  9. Reducing the Impact of Inappropriate Items on Reviewable Computerized Adaptive Testing

    ERIC Educational Resources Information Center

    Yen, Yung-Chin; Ho, Rong-Guey; Liao, Wen-Wei; Chen, Li-Ju

    2012-01-01

    In a test, the testing score would be closer to examinee's actual ability when careless mistakes were corrected. In CAT, however, changing the answer of one item in CAT might cause the following items no longer appropriate for estimating the examinee's ability. These inappropriate items in a reviewable CAT might in turn introduce bias in ability…

  10. Adaptive random testing with combinatorial input domain.

    PubMed

    Huang, Rubing; Chen, Jinfu; Lu, Yansheng

    2014-01-01

    Random testing (RT) is a fundamental testing technique to assess software reliability, by simply selecting test cases in a random manner from the whole input domain. As an enhancement of RT, adaptive random testing (ART) has better failure-detection capability and has been widely applied in different scenarios, such as numerical programs, some object-oriented programs, and mobile applications. However, not much work has been done on the effectiveness of ART for the programs with combinatorial input domain (i.e., the set of categorical data). To extend the ideas to the testing for combinatorial input domain, we have adopted different similarity measures that are widely used for categorical data in data mining and have proposed two similarity measures based on interaction coverage. Then, we propose a new version named ART-CID as an extension of ART in combinatorial input domain, which selects an element from categorical data as the next test case such that it has the lowest similarity against already generated test cases. Experimental results show that ART-CID generally performs better than RT, with respect to different evaluation metrics.

  11. Assessment of platelet function in healthy sedated cats using three whole blood platelet function tests.

    PubMed

    Ho, Kimberly K; Abrams-Ogg, Anthony C G; Wood, R Darren; O'Sullivan, M Lynne; Kirby, Gordon M; Blois, Shauna L

    2015-05-01

    The objectives of this study were to establish feline references intervals for 3 commercial whole blood platelet function test analyzer systems: Multiplate analyzer (MP; Roche Diagnostics International Ltd., Rotkreuz, Switzerland), Platelet Function Analyzer-100 (PF: Siemens Canada, Mississauga, Ontario, Canada), and Plateletworks Combo-25 kit (PW; Helena Laboratories, Beaumont, TX). Venipuncture was performed on 55 healthy sedated cats, and platelet aggregation in response to adenosine diphosphate (ADP), collagen (COL), and arachidonic acid (AA; MP only) was assessed using citrated blood. For the MP analyzer, median (95% confidence intervals [CIs]) area under curve (Units) for ADP, COL, and AA agonists were 87 (11-176), 81 (32-129), and 91 (59-129), respectively. For the PF analyzer, median (95% CIs) closure time, using COL-ADP cartridges, was 69 (46-89) sec. For the PW assay, median (95% CIs) percent aggregations for ADP and COL agonists were 71 (18-92) and 49 (9-96), respectively, using impedance hematology analyzer platelet counts, and 94 (25-98) and 68 (14-119), respectively, using flow cytometry hematology analyzer platelet counts. There were low correlations between the PF analyzer (COL-ADP cartridge) and MP analyzer (COL agonist; ρ = 0.11), and between the PF analyzer (COL-ADP cartridge) and PW assay (COL agonist using impedance platelet counts; ρ = 0.14). The PW assay percent aggregations using impedance and flow cytometric platelet counts were correlated for both ADP (ρ = 0.64) and COL (ρ = 0.64) agonists. Platelet function testing using these tests are feasible in cats, but 95% CIs are wide, so single results may be difficult to interpret. Platelet counting by impedance or flow cytometry may be used for the PW assay but are not interchangeable.

  12. Implementation and Measurement Efficiency of Multidimensional Computerized Adaptive Testing

    ERIC Educational Resources Information Center

    Wang, Wen-Chung; Chen, Po-Hsi

    2004-01-01

    Multidimensional adaptive testing (MAT) procedures are proposed for the measurement of several latent traits by a single examination. Bayesian latent trait estimation and adaptive item selection are derived. Simulations were conducted to compare the measurement efficiency of MAT with those of unidimensional adaptive testing and random…

  13. Existence of Two Distinct Infectious Endogenous Retroviruses in Domestic Cats and Their Different Strategies for Adaptation to Transcriptional Regulation

    PubMed Central

    Kuse, Kyohei; Ito, Jumpei; Miyake, Ariko; Kawasaki, Junna; Watanabe, Shinya; Makundi, Isaac; Ngo, Minh Ha; Otoi, Takeshige

    2016-01-01

    ABSTRACT Endogenous retroviruses (ERVs) are the remnants of ancient retroviral infections of germ cells. Previous work identified one of the youngest feline ERV groups, ERV-DC, and reported that two ERV-DC loci, ERV-DC10 and ERV-DC18 (ERV-DC10/DC18), can replicate in cultured cells. Here, we identified another replication-competent provirus, ERV-DC14, on chromosome C1q32. ERV-DC14 differs from ERV-DC10/DC18 in its phylogeny, receptor usage, and, most notably, transcriptional activities; although ERV-DC14 can replicate in cultured cells, it cannot establish a persistent infection owing to its low transcriptional activity. Furthermore, we examined ERV-DC transcription and its regulation in feline tissues. Quantitative reverse transcription-PCR (RT-PCR) detected extremely low ERV-DC10 expression levels in feline tissues, and bisulfite sequencing showed that 5′ long terminal repeats (LTRs) of ERV-DC10/DC18 are significantly hypermethylated in feline blood cells. Reporter assays found that the 5′-LTR promoter activities of ERV-DC10/DC18 are high, whereas that of ERV-DC14 is low. This difference in promoter activity is due to a single substitution from A to T in the LTR, and reverse mutation at this nucleotide in ERV-DC14 enhanced its replication and enabled it to persistently infect cultured cells. Therefore, ERV-DC LTRs can be divided into two types based on this nucleotide, the A type or T type, which have strong or attenuated promoter activity, respectively. Notably, ERV-DCs with T-type LTRs, such as ERV-DC14, have expanded in the cat genome significantly more than A-type ERV-DCs, despite their low promoter activities. Our results provide insights into how the host controls potentially infectious ERVs and, conversely, how ERVs adapt to and invade the host genome. IMPORTANCE The domestic cat genome contains many endogenous retroviruses, including ERV-DCs. These ERV-DCs have been acquired through germ cell infections with exogenous retroviruses. Some of these ERV

  14. Evaluation of the low-dose dexamethasone suppression test and ultrasonographic measurements of the adrenal glands in cats with diabetes mellitus.

    PubMed

    Kley, S; Alt, M; Zimmer, C; Hoerauf, A; Reusch, C E

    2007-11-01

    The objectives of the study were to evaluate the low-dose dexamethasone suppression (LDDS) test and the size of the adrenal glands via ultrasonography in cats with diabetes mellitus. Twenty-two cats were enrolled in the study. In 19 cats, suppression of cortisol concentrations below 5.5 nmol/litre occurred four and eight hours after intravenous administration of dexamethasone (0.1 mg/kg). In one other cat, the cortisol concentration was also below 5.5 nmol/litre at eight hours but was 11.0 nmol/litre at four hours. The results were in agreement with those of healthy cats in a previous study. The cortisol concentrations four and eight hours after administration of dexamethasone did not differ between cats with good glycemic control (n = 8) and those with moderate to poor control (n = 12). The adrenal glands of the diabetic cats were not enlarged compared with those of healthy cats. In two diabetic cats, the LDDS test results were abnormal. One cat had a pituitary adenoma and adrenal glands of normal size as determined by ultrasonography. The size of the adrenal glands of the other cat clearly differed; histological examination of the larger adrenal gland revealed an adrenocortical adenoma. Based on our findings, the results of the LDDS test using 0.1 mg/kg of dexamethasone are normal in cats with diabetes mellitus independent of the quality of glycemic control. In addition, diabetes mellitus does not lead to a measurable increase in the size of the adrenal glands in cats. Further studies are needed to evaluate if the dexamethasone dosage used in this study is useful to diagnose mild form of hypercortisolism.

  15. Adaptive interferometric null testing for unknown freeform optics metrology.

    PubMed

    Huang, Lei; Choi, Heejoo; Zhao, Wenchuan; Graves, Logan R; Kim, Dae Wook

    2016-12-01

    We report an adaptive interferometric null testing method for overcoming the dynamic range limitations of conventional null testing approaches during unknown freeform optics metrology or optics manufacturing processes that require not-yet-completed surface measurements to guide the next fabrication process. In the presented adaptive method, a deformable mirror functions as an adaptable null component for an unknown optical surface. The optimal deformable mirror's shape is determined by the stochastic parallel gradient descent algorithm and controlled by a deflectometry system. An adaptive interferometric null testing setup was constructed, and its metrology data successfully demonstrated superb adaptive capability in measuring an unknown surface.

  16. Seroprevalence of Coxiella burnetii in domesticated and feral cats in eastern Australia.

    PubMed

    Shapiro, Amanda J; Bosward, Katrina L; Heller, Jane; Norris, Jacqueline M

    2015-05-15

    The seroprevalence of Coxiella burnetii (C. burnetii) in cats in eastern Australia is unknown, and the risk of transmission from cats to humans is undetermined. This study aimed to determine the exposure of cats to C. burnetii in four distinct cat subpopulations. An indirect immunofluoresence assay (IFA) and an Enzyme-linked immunosorbent assay (ELISA) used for detection of anti-C. burnetii antibodies in humans were adapted, verified for use on feline serum, and compared. Cat serum samples (n=712) were tested with IFA from four subpopulations [cattery-confined breeding cats, pet cats, feral cats and shelter cats]. The proportions of seropositive cats were; cattery-confined breeding cats (35/376, 9.3%), pets (2/198, 1%), feral cats (0/50), shelter cats (0/88). The significant variables in C. burnetii seropositivity were cattery-confined breeding cat subpopulation and sterilisation status, with infected cats 17.1 (CI 4.2-70.2; P<0.001) times more likely to be cattery-confined breeding cats and 6.00 (CI 2.13-16.89; P<0.001) times more likely to be entire than sterilised. ELISA was used on 143 of 712 sera tested with IFA, and the Cohen's Kappa coefficient of 0.75 indicated 92.2% agreement between the two assays. These results confirm that Australian cats have been exposed to C. burnetii and that a higher seroprevalence of C. burnetii is seen amongst cattery-confined breeding cats. Cat breeders and veterinary personnel involved in feline reproductive procedures may be at higher risk of exposure to C. burnetii.

  17. The Estimation of Item Difficulty from Restricted CAT Calibration Samples.

    ERIC Educational Resources Information Center

    Sykes, Robert C.; Ito, Kyoko

    Whether the presence of bidimensionality has any effect on the adaptive recalibration of test items was studied through live-data simulation of computer adaptive testing (CAT) forms. The source data were examinee responses to the 298 scored multiple choice items of a licensure examination in a health care profession. Three 75-item part-forms,…

  18. An electron microscopic study of terminals of rapidly adapting mechanoreceptive afferent fibers in the cat spinal cord.

    PubMed

    Semba, K; Masarachia, P; Malamed, S; Jacquin, M; Harris, S; Yang, G; Egger, M D

    1985-02-08

    The intra-axonal horseradish peroxidase technique was used to examine the central terminals of 7 A beta primary afferent fibers from rapidly adapting (RA) mechanoreceptors in the glabrous skin of the cat's hindpaw. At the light microscopic level, labelled collaterals were seen to bear occasional boutonlike swellings, mostly (75-82%) of the en passant type. These swellings were distributed more or less uniformly from lamina III to a dorsal part of lamina VI in the dorsal horn, over a maximum longitudinal extent of about 4 mm. At the electron microscopic level, we observed that labelled boutons of RA afferent fibers were 1.0 to 3.3 micrometers in longest sectional dimension, and contained clear, round synaptic vesicles. They frequently formed asymmetric axospinous and axodendritic synapses and commonly appeared to receive contacts from unlabelled structures containing flattened or pleomorphic vesicles plus occasional large dense-cored vesicles. The examination of synaptic connectivity over the entire surface of individual boutons indicated that RA afferent boutons each made contacts with an average of one spine and one dendrite and, in addition, appeared to be postsynaptic to an average of two unlabelled vesicle-containing structures. This synaptic organization was, in general, more complex than that we had seen previously in Pacinian corpuscle (PC) and slowly adapting (SA) type I mechanoreceptive afferent fibers. Our findings indicate that RA, SA, and PC afferent terminals, while displaying some differential synaptic organizations, have many morphological and synaptological characteristics in common. These afferent terminals, in turn, seem to be generally distinguishable from the terminals of muscle spindle Ia afferents or unmyelinated primary afferents.

  19. Assessing Existing Item Bank Depth for Computer Adaptive Testing.

    ERIC Educational Resources Information Center

    Bergstrom, Betty A.; Stahl, John A.

    This paper reports a method for assessing the adequacy of existing item banks for computer adaptive testing. The method takes into account content specifications, test length, and stopping rules, and can be used to determine if an existing item bank is adequate to administer a computer adaptive test efficiently across differing levels of examinee…

  20. Multidimensional Adaptive Testing with Optimal Design Criteria for Item Selection

    ERIC Educational Resources Information Center

    Mulder, Joris; van der Linden, Wim J.

    2009-01-01

    Several criteria from the optimal design literature are examined for use with item selection in multidimensional adaptive testing. In particular, it is examined what criteria are appropriate for adaptive testing in which all abilities are intentional, some should be considered as a nuisance, or the interest is in the testing of a composite of the…

  1. The Development and Evaluation of a Computerized Adaptive Testing System.

    ERIC Educational Resources Information Center

    de-la-Torre, Roberto; Vispoel, Walter P.

    The development and preliminary evaluation of the Computerized Adaptive Testing System (CATSYS), a new testing package for IBM-compatible microcomputers, are described. CATSYS can be used to administer and score operational adaptive tests or to conduct on-line computer simulation studies. The package incorporates several innovative features,…

  2. A Comparison of Content-Balancing Procedures for Estimating Multiple Clinical Domains in Computerized Adaptive Testing: Relative Precision, Validity, and Detection of Persons with Misfitting Responses

    ERIC Educational Resources Information Center

    Riley, Barth B.; Dennis, Michael L.; Conrad, Kendon J.

    2010-01-01

    This simulation study sought to compare four different computerized adaptive testing (CAT) content-balancing procedures designed for use in a multidimensional assessment with respect to measurement precision, symptom severity classification, validity of clinical diagnostic recommendations, and sensitivity to atypical responding. The four…

  3. An Item Response Theory-Based, Computerized Adaptive Testing Version of the MacArthur-Bates Communicative Development Inventory: Words & Sentences (CDI:WS)

    ERIC Educational Resources Information Center

    Makransky, Guido; Dale, Philip S.; Havmose, Philip; Bleses, Dorthe

    2016-01-01

    Purpose: This study investigated the feasibility and potential validity of an item response theory (IRT)-based computerized adaptive testing (CAT) version of the MacArthur-Bates Communicative Development Inventory: Words & Sentences (CDI:WS; Fenson et al., 2007) vocabulary checklist, with the objective of reducing length while maintaining…

  4. Testing the metabolic hypothesis of O2 chemoreception in the cat carotid body in vitro.

    PubMed

    Buerk, D G; Iturriaga, R; Lahiri, S

    1994-03-01

    It is known that oligomycin reduces the oxidative phosphorylation high-energy state or high-energy intermediates by inhibiting the formation of ATP without directly inhibiting electron transport, whereas metabolic uncouplers dissipate the high-energy state without net production of ATP. The metabolic hypothesis for O2 chemoreception in the carotid body (CB) predicts that 1) oligomycin should diminish O2 consumption and attenuate O2 chemoreception and 2) uncouplers should reverse the effect of oligomycin by increasing O2 consumption without restoring O2 chemoreception. These predictions were tested by simultaneously measuring CB chemosensory discharge from the sinus nerve and the rate of tissue O2 disappearance (dPO2/dt) during interruption of perfusate flow in perfused-superfused cat CB preparations (n = 9). O2 consumption was calculated from dPO2/dt. Flow-interruption responses were measured before and after oligomycin (1-microgram bolus) and subsequently after dinitrophenol (50 microM). Chemosensory responses to bolus injections of hypercapnic Tyrode solution, cyanide, or nicotine were also tested periodically. Oligomycin diminished dPO2/dt from -2.67 +/- 0.30 to -2.02 +/- 0.19 (SE) Torr/s (P < 0.004, paired t test) and reduced the maximal sensory response from 196 +/- 43 to 124 +/- 12 impulses/s (P < 0.002, paired t test) while augmenting the initial response to CO2. Dinitrophenol reversed the metabolic depressant effect of oligomycin but further suppressed the chemosensory response. These results confirm the above predictions and strengthen the metabolic hypothesis for O2 chemoreception in the CB.

  5. Motion sickness in cats - A symptom rating scale used in laboratory and flight tests

    NASA Technical Reports Server (NTRS)

    Suri, K. B.; Daunton, N. G.; Crampton, G. H.

    1979-01-01

    The cat is proposed as a model for the study of motion and space sickness. Development of a scale for rating the motion sickness severity in the cat is described. The scale is used to evaluate an antimotion sickness drug, d-amphetamine plus scopolamine, and to determine whether it is possible to predict sickness susceptibility during parabolic flight, including zero-G maneuvers, from scores obtained during ground based trials.

  6. A Method for Severely Constrained Item Selection in Adaptive Testing.

    ERIC Educational Resources Information Center

    Stocking, Martha L.; Swanson, Len

    1993-01-01

    A method is presented for incorporating a large number of constraints on adaptive item selection in the construction of computerized adaptive tests. The method, which emulates practices of expert test specialists, is illustrated for verbal and quantitative measures. Its foundation is application of a weighted deviations model and algorithm. (SLD)

  7. Evaluating the Content Validity of Multistage-Adaptive Tests

    ERIC Educational Resources Information Center

    Crotts, Katrina; Sireci, Stephen G.; Zenisky, April

    2012-01-01

    Validity evidence based on test content is important for educational tests to demonstrate the degree to which they fulfill their purposes. Most content validity studies involve subject matter experts (SMEs) who rate items that comprise a test form. In computerized-adaptive testing, examinees take different sets of items and test "forms"…

  8. Turkish Adaptation of Test of Pretended Play

    ERIC Educational Resources Information Center

    Aydin, Aydan

    2012-01-01

    The objective of present research is to conduct validity and reliability analysis of the verbal section of Test of Pretended Play that will measure pretended play behaviors of pre-school age children (3-6 years of age). Test of Pretended Play was first developed by Vicky Lewis and Jill Boucher in 1997. This test aimed to measure pretended play…

  9. An Automatic Online Calibration Design in Adaptive Testing

    ERIC Educational Resources Information Center

    Makransky, Guido; Glas, Cees A. W.

    2010-01-01

    An accurately calibrated item bank is essential for a valid computerized adaptive test. However, in some settings, such as occupational testing, there is limited access to test takers for calibration. As a result of the limited access to possible test takers, collecting data to accurately calibrate an item bank in an occupational setting is…

  10. Modern Sequential Analysis and Its Applications to Computerized Adaptive Testing

    ERIC Educational Resources Information Center

    Bartroff, Jay; Finkelman, Matthew; Lai, Tze Leung

    2008-01-01

    After a brief review of recent advances in sequential analysis involving sequential generalized likelihood ratio tests, we discuss their use in psychometric testing and extend the asymptotic optimality theory of these sequential tests to the case of sequentially generated experiments, of particular interest in computerized adaptive testing. We…

  11. Comparison of the GnRH-stimulation test and a semiquantitative quick test for LH to diagnose presence of ovaries in the female domestic cat.

    PubMed

    Rohlertz, M; Ström Holst, B; Axnér, E

    2012-12-01

    It is generally recommended that female cats not intended for planned breeding are spayed to reduce the population of feral cats and also because spaying is beneficial for the long-term health of the individual. For female cats of unknown origin or with estrous symptoms after spaying there is a need for a reliable method to diagnose or rule out the presence of ovaries to avoid unnecessary surgery. Methods previously recommended include vaginal cytology, evaluation of serum estradiol concentration during suspected estrus, induction of ovulation and subsequent evaluation of progesterone, or explorative laparotomy. These methods have the disadvantages that an accurate diagnosis only can be made during estrus or that an invasive procedure is required. Previously, the use of a GnRH challenge test and a semiquantitative LH test have been reported. Our aim was to compare these two methods. We therefore divided 31 female cats in two groups: (1) intact nonestrous females (N = 16), and (2) previously ovariohysterectomized females (N = 15). A blood sample was collected (Time 0) and 0.4 μg/kg buserelin (Receptal; Intervet, Danderyd, Sweden) was injected im. A new blood sample was collected 120 min after the injection. A drop of serum from the sample collected at Time 0 was placed on the LH test (Witness LH; Synbiotics, Corp., San Diego, CA, USA) and the result was evaluated as negative or positive. The remaining serum was frozen and analyzed for estradiol in one batch. Serum estradiol before buserelin stimulation ranged between 5 and 45 pmol/L (N = 14) in intact nonestrous queens and between 2 and 6 pmol/L (N = 15) in ovariohysterectomized females. Estradiol in samples collected after 120 min ranged between 12 and 51 pmol/L (N = 16) in intact queens and between 1 and 7 pmol/L (N = 15) in spayed cats giving a sensitivity and specificity of 100% for the buserelin stimulation test at a cutoff value of 11 pmol/L. All intact queens were negative in the semiquantitative LH test

  12. A Sharing Item Response Theory Model for Computerized Adaptive Testing

    ERIC Educational Resources Information Center

    Segall, Daniel O.

    2004-01-01

    A new sharing item response theory (SIRT) model is presented that explicitly models the effects of sharing item content between informants and test takers. This model is used to construct adaptive item selection and scoring rules that provide increased precision and reduced score gains in instances where sharing occurs. The adaptive item selection…

  13. Application of Sequential Interval Estimation to Adaptive Mastery Testing

    ERIC Educational Resources Information Center

    Chang, Yuan-chin Ivan

    2005-01-01

    In this paper, we apply sequential one-sided confidence interval estimation procedures with beta-protection to adaptive mastery testing. The procedures of fixed-width and fixed proportional accuracy confidence interval estimation can be viewed as extensions of one-sided confidence interval procedures. It can be shown that the adaptive mastery…

  14. An electron microscopic study of primary afferent terminals from slowly adapting type I receptors in the cat.

    PubMed

    Semba, K; Masarachia, P; Malamed, S; Jacquin, M; Harris, S; Yang, G; Egger, M D

    1983-12-20

    Primary afferent fibers transmitting impulses from slowly adapting (SA) Type I receptors in the glabrous skin of the hind paw of the cat were injected intraaxonally in the spinal cord with horseradish peroxidase (HRP). At the light microscopic level, terminal arborizations were observed in the medial dorsal horn extending up to 6 mm rostrocaudally in and near the seventh lumbar segment. Boutonlike swellings labelled with HRP were distributed in clusters in Rexed's laminae III-VI. There was a tendency for the most dorsal clusters from an individual fiber to be located rostrally and for the most ventral clusters to be located caudally. At the electron microscopic level, a combination of morphometric analysis and serial reconstruction revealed the following: (1) All the boutons labelled with HRP contained predominantly clear, round synaptic vesicles, 40-50 nm in diameter. (2) Labelled boutons (n = 75) had cross-sectional longest dimensions of 1.72 +/- 0.53 micron (Mean +/- S.D.), perimeters of 4.95 +/- 1.52 micron, and areas of 1.18 +/- 0.59 micron 2. Their shapes in section varied from rounded to elongated forms. (3) The sizes of labelled boutons decreased significantly and linearly with depth from lamina IV to VI. The shapes of the bouton cross sections also became rounder with depth in the dorsal horn. (4) About 72% of synaptic contacts associated with HRP-filled boutons were with dendritic spines and shafts; most of these synapses were of the asymmetric type. (5) The remainder (28%) of the appositions were synapselike contacts between labelled boutons and unlabelled structures containing flattened or pleomorphic vesicles, and occasional dense-cored vesicles. (6) We observed no unequivocal axosomatic contacts made by labelled boutons. (7) The lengths of synaptic appositions with dendritic spines (0.46 +/- 0.20 micron) or with dendritic shafts (0.51 +/- 0.18 micron) were significantly greater than the synapselike contacts with vesicle-containing unlabelled

  15. Two-Phase Item Selection Procedure for Flexible Content Balancing in CAT

    ERIC Educational Resources Information Center

    Cheng, Ying; Chang, Hua-Hua; Yi, Qing

    2007-01-01

    Content balancing is an important issue in the design and implementation of computerized adaptive testing (CAT). Content-balancing techniques that have been applied in fixed content balancing, where the number of items from each content area is fixed, include constrained CAT (CCAT), the modified multinomial model (MMM), modified constrained CAT…

  16. Online Calibration via Variable Length Computerized Adaptive Testing

    ERIC Educational Resources Information Center

    Chang, Yuan-chin Ivan; Lu, Hung-Yi

    2010-01-01

    Item calibration is an essential issue in modern item response theory based psychological or educational testing. Due to the popularity of computerized adaptive testing, methods to efficiently calibrate new items have become more important than that in the time when paper and pencil test administration is the norm. There are many calibration…

  17. Psychometric Evaluation of the Lower Extremity Computerized Adaptive Test, the Modified Harris Hip Score, and the Hip Outcome Score

    PubMed Central

    Hung, Man; Hon, Shirley D.; Cheng, Christine; Franklin, Jeremy D.; Aoki, Stephen K.; Anderson, Mike B.; Kapron, Ashley L.; Peters, Christopher L.; Pelt, Christopher E.

    2014-01-01

    Background: The applicability and validity of many patient-reported outcome measures in the high-functioning population are not well understood. Purpose: To compare the psychometric properties of the modified Harris Hip Score (mHHS), the Hip Outcome Score activities of daily living subscale (HOS-ADL) and sports (HOS-sports), and the Lower Extremity Computerized Adaptive Test (LE CAT). The hypotheses was that all instruments would perform well but that the LE CAT would show superiority psychometrically because a combination of CAT and a large item bank allows for a high degree of measurement precision. Study Design: Cohort study (diagnosis); Level of evidence, 2. Methods: Data were collected from 472 advanced-age, active participants from the Huntsman World Senior Games in 2012. Validity evidences were examined through item fit, dimensionality, monotonicity, local independence, differential item functioning, person raw score to measure correlation, and instrument coverage (ie, ceiling and floor effects), and reliability evidences were examined through Cronbach alpha and person separation index. Results: All instruments demonstrated good item fit, unidimensionality, monotonicity, local independence, and person raw score to measure correlations. The HOS-ADL had high ceiling effects of 36.02%, and the mHHS had ceiling effects of 27.54%. The LE CAT had ceiling effects of 8.47%, and the HOS-sports had no ceiling effects. None of the instruments had any floor effects. The mHHS had a very low Cronbach alpha of 0.41 and an extremely low person separation index of 0.08. Reliabilities for the LE CAT were excellent and for the HOS-ADL and HOS-sports were good. Conclusion: The LE CAT showed better psychometric properties overall than the HOS-ADL, HOS-sports, and mHHS for the senior population. The mHHS demonstrated pronounced ceiling effects and poor reliabilities that should be of concern. The high ceiling effects for the HOS-ADL were also of concern. The LE CAT was superior

  18. A Computer-Adaptive Vocabulary Test

    ERIC Educational Resources Information Center

    Molina, Maria Teresa Lopez-Mezquita

    2009-01-01

    Lexical competence is considered to be an essential step in the development and consolidation of a student's linguistic ability, and thus the reliable assessment of such competence turns out to be a fundamental aspect in this process. The design and construction of vocabulary tests has become an area of special interest, as it may provide teachers…

  19. An overview of glomerular filtration rate testing in dogs and cats

    PubMed Central

    Von Hendy-Willson, Vanessa E.; Pressler, Barrak M.

    2010-01-01

    Determination of glomerular filtration rate (GFR) is a valuable, yet underused, diagnostic tool for evaluating renal function in dogs and cats. This article first reviews the hormonal and hemodynamic factors which contribute to GFR, followed by a description of considerations when selecting a pharmacokinetic model and methods of animal-to-animal standardization. The best-characterized existing GFR markers, including creatinine, radiolabeled markers, and iohexol, are reviewed in depth, as well as alternative but lesser-used techniques. A weighted means analysis of reported GFR measurements in healthy dogs and cats and a review of selected studies that have examined GFR alterations in animals with naturally-occurring and experimental diseases provide the reader with preliminary guidelines on expected GFR results in these species and disease conditions. PMID:20541957

  20. [Peritoneal equilibration test: Conventional versus adapted. Preliminary study].

    PubMed

    Zaloszyc, Ariane; Schmitt, Claus Peter; Schaefer, Betti; Doutey, Armelle; Terzic, Joëlle; Menouer, Soraya; Higel, Laetitia; Fischbach, Michel

    2017-02-01

    Conventional automated peritoneal dialysis (APD) is prescribed as a repetition of cycles with the same dwell time and the same fill volume. Water and sodium balance remains a common problem among patients on peritoneal dialysis. More recently, adapted automated peritoneal dialysis was described, as a combination of short dwells with a low volume, in order to enhance ultrafiltration, followed by long dwells with a large fill volume to favor solute removal. We performed a preliminary crossover study on 4 patients. The total amount of dialysate was the same, i.e. 2L/m(2) as well as the total duration of the test, i.e. 150 minutes. The conventional test was made with two identical cycles, each cycle had a fill volume of 1L/m(2) and a duration of 75 minutes, while the adapted test was performed with one short cycle, i.e. 30 minutes with a low fill volume, i.e. 0.6L/m(2), followed by a long cycle, i.e. 120 minutes, with a large fill volume, i.e. 1.4L/m(2). Sodium extraction was improved by 29.3mmol/m(2) (169%) in the adapted test in comparison to the conventional test. Ultrafiltration was enhanced by 159mL/m(2) (128%) in the adapted test compared to the conventional one. Glucose absorption was decreased by 35% in the adapted test in comparison to the conventional test and osmotic conductance was also improved. In conclusion, adapted dialysis may allow for a better volume and sodium balance, since we observed an improvement in sodium extraction and ultrafiltration. This pre-study authorizes an improvement of the European Pediatric Study's protocol on Adapted APD, already started and which will continue in the next months.

  1. Cat scratch encephalopathy.

    PubMed

    Silver, B E; Bean, C S

    1991-06-01

    Cat scratch disease is usually benign, self-limited and without sequelae. Margileth has established four clinical criteria, three of which must be satisfied to make the diagnosis: 1) a history of animal exposure, usually kitten, with primary skin or ocular lesions; 2) regional chronic adenopathy without other apparent cause; 3) a positive cat scratch disease antigen skin test; and 4) lymph node biopsy demonstrating noncaseating granulomas and germinal center hyperplasia. Central nervous system involvement in cat scratch disease has been previously reported, although it is extremely uncommon. In a several-month period, we encountered two cases of cat scratch disease complicated by encephalopathy. The intents of this paper are twofold: 1) to briefly review the current literature on cat scratch disease, 2) to demonstrate that cat scratch disease complicated by encephalopathy presents acutely with seizures, posturing and coma and resolves rapidly with supportive care.

  2. Adaptive changes of the locomotor pattern and cutaneous reflexes during locomotion studied in the same cats before and after spinalization.

    PubMed

    Frigon, Alain; Rossignol, Serge

    2008-06-15

    Descending supraspinal inputs exert powerful influences on spinal reflex pathways in the legs. Removing these inputs by completely transecting the spinal cord changes the state (i.e. the configuration of the spinal circuitry) of the locomotor network and undoubtedly generates a reorganization of reflex pathways. To study changes in reflex pathways after a complete spinalization, we recorded spinal reflexes during locomotion before and after a complete transection of the spinal cord at the 13th thoracic segment in cats. We chronically implanted electrodes in three cats, to record electromyography (EMG) in several hindlimb muscles and around the left tibial (Tib) nerve at the ankle to elicit reflexes during locomotion before and after spinalization in the same cat. Control values of kinematics, EMGs and reflexes were obtained during intact locomotion for 33-60 days before spinalization. After spinalization, cats were trained 3-5 times a week on a motorized treadmill. Recordings resumed once a stable spinal locomotion was achieved (26-43 days), with consistent plantar foot placement and full hindquarter weight support without perineal stimulation. Changes in Tib nerve reflex responses after spinalization in the same cat during locomotion were found in all muscles studied and were often confined to specific phases of the step cycle. The most remarkable change was the appearance of short-latency excitatory responses in some ipsilateral ankle extensors during stance. Short-latency excitatory responses in the ipsilateral tibialis anterior were increased during stance, whereas in other flexors such as semitendinosus and sartorius, increases were mostly confined to swing. Longer-latency excitatory responses in ipsilateral flexors were absent or reduced. Responses evoked in limb muscles contralateral to stimulation were generally increased throughout the step cycle. These reflex changes after spinalization provide important clues regarding the functional reorganization of

  3. [European Portuguese EARS test battery adaptation].

    PubMed

    Alves, Marisa; Ramos, Daniela; Oliveira, Graça; Alves, Helena; Anderson, Ilona; Magalhães, Isabel; Martins, Jorge H; Simões, Margarida; Ferreira, Raquel; Fonseca, Rita; Andrade, Susana; Silva, Luís; Ribeiro, Carlos; Ferreira, Pedro Lopes

    2014-01-01

    Introdução: A utilização de instrumentos de avaliação em saúde adequados é fundamental na gestão da prestação de cuidados. A escassez, em Portugal, de instrumentos específicos para a avaliação do desempenho de crianças utilizadoras de implantes cocleares motivou o trabalho de tradução e de adaptação da bateria de testes EARS (Evaluation of Auditory Responses to Speech) para o português europeu. Esta bateria de testes é hoje um dos instrumentos mais comummente utilizados por equipas de (re)habilitação de crianças surdas com implantes cocleares em todo o mundo. O objetivo a atingir com a validação do EARS foi fornecer às equipas de (re)habilitação um instrumento que permita: (i) monitorizar a evolução individual da reabilitação; (ii) gerir um programa de (re)habilitação de acordo com resultados objetivos, comparáveis entre diferentes equipas de (re)habilitação; (iii) obter dados comparáveis comequipas internacionais; e (iv) melhorar a adesão e a motivação da família e restantes profissionais no ambulatório.Material e Métodos: No processo de tradução e de adaptação da bateria de testes, os procedimentos adotados foram os seguintes: (i) tradução da versão inglesa para português europeu por um tradutor profissional; (ii) revisão dessa tradução realizada por um painel de especialistas constituído por otorrinolaringologistas, terapeutas da fala e técnicos de audiologia; (iii) adaptação dos estímulos de teste pela equipa de terapeutas da fala; e (iv) nova revisão por parte do painel de especialistas.Resultados: São apresentados, para cada um dos instrumentos que compõem a bateria EARS, as adaptações introduzidas, conciliando as características e os objetivos originais dos instrumentos com as particularidades linguísticas e culturais da população portuguesa.Discussão: São discutidas as dificuldades encontradas durante o processo de tradução e de adaptação e as soluções adotadas. São feitas

  4. An adaptive interferometer for optical testing .

    NASA Astrophysics Data System (ADS)

    Pariani, G.; Colella, L.; Bertarelli, C.; Aliverti, M.; Riva, M.; Bianco, A.

    Interferometry is a well-established technique to test optical elements. However, its use is challenging in the case of free-form and aspheric elements, due to the lack of the reference optics. The proposed idea concerns the development of a versatile interferometer, where its reference arm is equipped with a reprogrammable Computer Generated Hologram. This principle takes advantage from our study on photochromic materials for optical applications, which shows a strong and reversible modulation of transparency in the visible region. The encoding of the desired hologram can be done off-line, or directly into the interferometer, and different patterns may be realized sequentially after the erasing of the previous hologram. We report on the present state of the research and on the future perspectives. skip=5pt

  5. Deriving Stopping Rules for Multidimensional Computerized Adaptive Testing

    ERIC Educational Resources Information Center

    Wang, Chun; Chang, Hua-Hua; Boughton, Keith A.

    2013-01-01

    Multidimensional computerized adaptive testing (MCAT) is able to provide a vector of ability estimates for each examinee, which could be used to provide a more informative profile of an examinee's performance. The current literature on MCAT focuses on the fixed-length tests, which can generate less accurate results for those examinees whose…

  6. Computerized Adaptive Testing: From Inquiry to Operation [Book Review].

    ERIC Educational Resources Information Center

    Gierl, Mark J.

    1998-01-01

    This book documents the research, development, and implementation efforts that allowed the U.S. Department of Defense to initiate the Computerized Adaptive Testing Armed Services Vocational Aptitude Battery Program for enlistment testing. Traces the history of this program over 30 years. (SLD)

  7. Proceedings of the 1977 Computerized Adaptive Testing Conference.

    ERIC Educational Resources Information Center

    Weiss, David J., Ed.

    The 27 papers in this collection (26 of which were presented at the conference) are organized according to the eight topical sessions: (1) Improving Ability Measurement Using Different Item Formats, (2) Alternative Models for Adaptive Testing, (3) Psychological and Subgroup Effects, (4) Performance Testing by Interactive Simulation, (5)…

  8. Multidimensional Computerized Adaptive Testing for Indonesia Junior High School Biology

    ERIC Educational Resources Information Center

    Kuo, Bor-Chen; Daud, Muslem; Yang, Chih-Wei

    2015-01-01

    This paper describes a curriculum-based multidimensional computerized adaptive test that was developed for Indonesia junior high school Biology. In adherence to the Indonesian curriculum of different Biology dimensions, 300 items was constructed, and then tested to 2238 students. A multidimensional random coefficients multinomial logit model was…

  9. Some Properties of a Bayesian Adaptive Ability Testing Strategy.

    ERIC Educational Resources Information Center

    McBride, James R.; Weiss, David J.

    Four monte carlo simulation studies of Owen's Bayesian sequential procedure for adaptive mental testing were conducted. Whereas previous simulation studies of this procedure have concentrated on evaluating it in terms of the correlation of its test scores with simulated ability in a normal population, these four studies explored a number of…

  10. Optimal Design of Item Banks for Computerized Adaptive Tests.

    ERIC Educational Resources Information Center

    Stocking, Martha L.; Swanson, Len

    1998-01-01

    Applied optimal design methods to the item-bank design of adaptive testing for continuous testing situations using a version of the weighted-deviations model (M. Stocking and L. Swanson, 1993) in a simulation. Independent and overlapping item banks used items more efficiently than did a large item bank. (SLD)

  11. Mutual Information Item Selection in Adaptive Classification Testing

    ERIC Educational Resources Information Center

    Weissman, Alexander

    2007-01-01

    A general approach for item selection in adaptive multiple-category classification tests is provided. The approach uses mutual information (MI), a special case of the Kullback-Leibler distance, or relative entropy. MI works efficiently with the sequential probability ratio test and alleviates the difficulties encountered with using other local-…

  12. Computerized Adaptive Testing through the World Wide Web.

    ERIC Educational Resources Information Center

    Shermis, Mark D.; Mzumara, Howard; Brown, Mike; Lillig, Clo

    An important problem facing institutions of higher education is the number of students reporting that they are not adequately prepared for the difficulty of college-level courses. To meet this problem, a computerized adaptive testing package was developed that permitted remote placement testing of high school students via the World Wide Web. The…

  13. A Procedure for Empirical Initialization of Adaptive Testing Algorithms.

    ERIC Educational Resources Information Center

    van der Linden, Wim J.

    In constrained adaptive testing, the numbers of constraints needed to control the content of the tests can easily run into the hundreds. Proper initialization of the algorithm becomes a requirement because the presence of large numbers of constraints slows down the convergence of the ability estimator. In this paper, an empirical initialization of…

  14. Computerized Classification Testing with the Rasch Model

    ERIC Educational Resources Information Center

    Eggen, Theo J. H. M.

    2011-01-01

    If classification in a limited number of categories is the purpose of testing, computerized adaptive tests (CATs) with algorithms based on sequential statistical testing perform better than estimation-based CATs (e.g., Eggen & Straetmans, 2000). In these computerized classification tests (CCTs), the Sequential Probability Ratio Test (SPRT) (Wald,…

  15. Cleanup and treatment (CAT) test: a land-area decontamination project utilizing a vacuum method of soil removal

    SciTech Connect

    Orcutt, J.A.

    1982-08-01

    Areas 11 and 13 of the Nevada Test Site (NTS) are contaminated with varying concentrations of Pu-239, 240 and Am-241. An investigation of a vacuum method of soil removal, the Cleanup and Treatment (CAT) test, was conducted over a 3-month period in the plutonium safety shot or Plutonium Valley portion of Area 11. Soil in Plutonium Valley is of the Aridisol Order. The surface 0 to 10 cm is a gravelly loam, and is strongly alkaline (pH 8.8). A large truck-mounted vacuum unit, rather than conventional earth-moving equipment, was used as the primary soil collection unit. Effectiveness of the vacuum method of soil removal was evaluated in relation to conventional earthmoving procedures, particularly in terms of volume reduction of removed soil achieved over conventional techniques. Radiological safety considerations associated with use of the vacuum unit were evaluated in relation to their impact on a full-scale land decontamination program. Environmental and operational impacts of devegetation with retention of root crowns or root systems were investigated. It is concluded that the CAT test was successful under difficult environmental conditions.

  16. Cat-scratch Disease.

    PubMed

    Klotz, Stephen A; Ianas, Voichita; Elliott, Sean P

    2011-01-15

    Cat-scratch disease is a common infection that usually presents as tender lymphadenopathy. It should be included in the differential diagnosis of fever of unknown origin and any lymphadenopathy syndrome. Asymptomatic, bacteremic cats with Bartonella henselae in their saliva serve as vectors by biting and clawing the skin. Cat fleas are responsible for horizontal transmission of the disease from cat to cat, and on occasion, arthropod vectors (fleas or ticks) may transmit the disease to humans. Cat-scratch disease is commonly diagnosed in children, but adults can present with it as well. The causative microorganism, B. henselae, is difficult to culture. Diagnosis is most often arrived at by obtaining a history of exposure to cats and a serologic test with high titers (greater than 1:256) of immunoglobulin G antibody to B. henselae. Most cases of cat-scratch disease are self-limited and do not require antibiotic treatment. If an antibiotic is chosen, azithromycin has been shown in one small study to speed recovery. Infrequently, cat-scratch disease may present in a more disseminated form with hepatosplenomegaly or meningoencephalitis, or with bacillary angiomatosis in patients with AIDS.

  17. Polytomous Adaptive Classification Testing: Effects of Item Pool Size, Test Termination Criterion, and Number of Cutscores

    ERIC Educational Resources Information Center

    Gnambs, Timo; Batinic, Bernad

    2011-01-01

    Computer-adaptive classification tests focus on classifying respondents in different proficiency groups (e.g., for pass/fail decisions). To date, adaptive classification testing has been dominated by research on dichotomous response formats and classifications in two groups. This article extends this line of research to polytomous classification…

  18. Testing the adaptive radiation hypothesis for the lemurs of Madagascar

    PubMed Central

    2017-01-01

    Lemurs, the diverse, endemic primates of Madagascar, are thought to represent a classic example of adaptive radiation. Based on the most complete phylogeny of living and extinct lemurs yet assembled, I tested predictions of adaptive radiation theory by estimating rates of speciation, extinction and adaptive phenotypic evolution. As predicted, lemur speciation rate exceeded that of their sister clade by nearly twofold, indicating the diversification dynamics of lemurs and mainland relatives may have been decoupled. Lemur diversification rates did not decline over time, however, as predicted by adaptive radiation theory. Optimal body masses diverged among dietary and activity pattern niches as lineages diversified into unique multidimensional ecospace. Based on these results, lemurs only partially fulfil the predictions of adaptive radiation theory, with phenotypic evolution corresponding to an ‘early burst’ of adaptive differentiation. The results must be interpreted with caution, however, because over the long evolutionary history of lemurs (approx. 50 million years), the ‘early burst’ signal of adaptive radiation may have been eroded by extinction. PMID:28280597

  19. Use of adaptive walls in 2D tests

    NASA Technical Reports Server (NTRS)

    Archambaud, J. P.; Chevallier, J. P.

    1984-01-01

    A new method for computing the wall effects gives precise answers to some questions arising in adaptive wall concept applications: length of adapted regions, fairings with up and downstream regions, residual misadjustments effects, reference conditions. The acceleration of the iterative process convergence and the development of an efficient technology used in CERT T2 wind tunnels give in a single run the required test conditions. Samples taken from CAST 7 tests demonstrate the efficiency of the whole process to obtain significant results with considerations of tridimensional case extension.

  20. HIDEC F-15 adaptive engine control system flight test results

    NASA Technical Reports Server (NTRS)

    Smolka, James W.

    1987-01-01

    NASA-Ames' Highly Integrated Digital Electronic Control (HIDEC) flight test program aims to develop fully integrated airframe, propulsion, and flight control systems. The HIDEC F-15 adaptive engine control system flight test program has demonstrated that significant performance improvements are obtainable through the retention of stall-free engine operation throughout the aircraft flight and maneuver envelopes. The greatest thrust increase was projected for the medium-to-high altitude flight regime at subsonic speed which is of such importance to air combat. Adaptive engine control systems such as the HIDEC F-15's can be used to upgrade the performance of existing aircraft without resort to expensive reengining programs.

  1. Validation of real-time polymerase chain reaction tests for diagnosing feline immunodeficiency virus infection in domestic cats using Bayesian latent class models.

    PubMed

    Morton, John M; McCoy, Richard J; Kann, Rebecca K C; Gardner, Ian A; Meers, Joanne

    2012-04-01

    The objectives of the current study were to estimate the sensitivity and specificity of three real-time polymerase chain reaction (PCR) tests for diagnosis of feline immunodeficiency virus (FIV) infection in domestic cats, both individually and when interpreted in series with one of two serological tests, separately in populations of cats at low and high risk of being infected with FIV. One PCR test targeted the pol gene and two targeted the gag gene of FIV. For comparison, sensitivities and specificities of the individual serological tests (IDEXX SNAP(®) test and AGEN Simplify(®) test) were also estimated. The study populations consisted of domestic cats thought to be not vaccinated against FIV. Low-risk (males aged 4 years or less and females; n=128) and high-risk (males over 4 years; n=128) cats were selected from those where blood samples were submitted to a commercial clinical pathology service. Bayesian latent class models were used to obtain posterior probability distributions for sensitivity and specificity for each test, based on prior distributions obtained from three experts. Medians of the posterior sensitivity distributions for the PCR tests based on the pol gene and two regions of the gag gene tests ranged from 0.85 to 0.89, compared to 0.89-0.97 for the two serological tests. The medians of posterior specificity distributions for these PCR tests were 0.94-0.96, and 0.95-0.97 for the serological tests. In contrast, the PCR based on one region of the gag gene had lower median sensitivity. Sensitivities of combinations of these serological and PCR tests interpreted in series were low; medians of posterior sensitivity distributions ranged from 0.75 to 0.83. Relative to the low-risk population, median sensitivities in the high-risk population were lower for all tests other than the AGEN Simplify(®) test; specificities were similar in both populations. We conclude that the sensitivities of the two PCR tests based on the pol gene and two regions of the

  2. Nearest Neighbors, Simple Strata, and Probabilistic Parameters: An Empirical Comparison of Methods for Item Exposure Control in CATs.

    ERIC Educational Resources Information Center

    Parshall, Cynthia G.; Kromrey, Jeffrey D.; Harmes, J. Christine; Sentovich, Christina

    Computerized adaptive tests (CATs) are efficient because of their optimal item selection procedures that target maximally informative items at each estimated ability level. However, operational administration of these optimal CATs results in a relatively small subset of items given to examinees too often, while another portion of the item pool is…

  3. Multidimensional CAT Item Selection Methods for Domain Scores and Composite Scores with Item Exposure Control and Content Constraints

    ERIC Educational Resources Information Center

    Yao, Lihua

    2014-01-01

    The intent of this research was to find an item selection procedure in the multidimensional computer adaptive testing (CAT) framework that yielded higher precision for both the domain and composite abilities, had a higher usage of the item pool, and controlled the exposure rate. Five multidimensional CAT item selection procedures (minimum angle;…

  4. Optimal Bayesian Adaptive Design for Test-Item Calibration.

    PubMed

    van der Linden, Wim J; Ren, Hao

    2015-06-01

    An optimal adaptive design for test-item calibration based on Bayesian optimality criteria is presented. The design adapts the choice of field-test items to the examinees taking an operational adaptive test using both the information in the posterior distributions of their ability parameters and the current posterior distributions of the field-test parameters. Different criteria of optimality based on the two types of posterior distributions are possible. The design can be implemented using an MCMC scheme with alternating stages of sampling from the posterior distributions of the test takers' ability parameters and the parameters of the field-test items while reusing samples from earlier posterior distributions of the other parameters. Results from a simulation study demonstrated the feasibility of the proposed MCMC implementation for operational item calibration. A comparison of performances for different optimality criteria showed faster calibration of substantial numbers of items for the criterion of D-optimality relative to A-optimality, a special case of c-optimality, and random assignment of items to the test takers.

  5. Brazilian Adaptation of the Woodcock-Johnson III Cognitive Tests

    ERIC Educational Resources Information Center

    Wechsler, Solange Muglia; Nunes, Carlos Sancineto; Schelini, Patricia Waltz; Pasian, Sonia Regina; Homsi, Silvia Vertoni; Moretti, Lucia; Anache, Alexandra Ayach

    2010-01-01

    An adaptation of the standard battery of Woodcock-Johnson III Tests of Cognitive Abilities (WJ-III) for Brazilian children and youth was investigated. The sample was composed of 1094 students (54 percent girls), ages 7-17, living in Sao Paulo state (91 percent). Items from Brazilian school books as well as from the WJ-III Spanish version…

  6. Computerized Adaptive Testing with Multiple-Form Structures

    ERIC Educational Resources Information Center

    Armstrong, Ronald D.; Jones, Douglas H.; Koppel, Nicole B.; Pashley, Peter J.

    2004-01-01

    A multiple-form structure (MFS) is an ordered collection or network of testlets (i.e., sets of items). An examinee's progression through the network of testlets is dictated by the correctness of an examinee's answers, thereby adapting the test to his or her trait level. The collection of paths through the network yields the set of all possible…

  7. Multiple Maximum Exposure Rates in Computerized Adaptive Testing

    ERIC Educational Resources Information Center

    Ramon Barrada, Juan; Veldkamp, Bernard P.; Olea, Julio

    2009-01-01

    Computerized adaptive testing is subject to security problems, as the item bank content remains operative over long periods and administration time is flexible for examinees. Spreading the content of a part of the item bank could lead to an overestimation of the examinees' trait level. The most common way of reducing this risk is to impose a…

  8. Alpha-Stratified Multistage Computerized Adaptive Testing with beta Blocking.

    ERIC Educational Resources Information Center

    Chang, Hua-Hua; Qian, Jiahe; Yang, Zhiliang

    2001-01-01

    Proposed a refinement, based on the stratification of items developed by D. Weiss (1973), of the computerized adaptive testing item selection procedure of H. Chang and Z. Ying (1999). Simulation studies using an item bank from the Graduate Record Examination show the benefits of the new procedure. (SLD)

  9. Computer Adaptive Testing for Small Scale Programs and Instructional Systems

    ERIC Educational Resources Information Center

    Rudner, Lawrence M.; Guo, Fanmin

    2011-01-01

    This study investigates measurement decision theory (MDT) as an underlying model for computer adaptive testing when the goal is to classify examinees into one of a finite number of groups. The first analysis compares MDT with a popular item response theory model and finds little difference in terms of the percentage of correct classifications. The…

  10. 21. DREDGING POND USED TO TEST THE ADAPTABILITY OF JET ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    21. DREDGING POND USED TO TEST THE ADAPTABILITY OF JET PUMPS FOR PUMPING SAND, AND WEAR RATES OF DIFFERENT TYPES OF DREDGING PIPE. - Waterways Experiment Station, Hydraulics Laboratory, Halls Ferry Road, 2 miles south of I-20, Vicksburg, Warren County, MS

  11. "MSTGen": Simulated Data Generator for Multistage Testing

    ERIC Educational Resources Information Center

    Han, Kyung T.

    2013-01-01

    Multistage testing, or MST, was developed as an alternative to computerized adaptive testing (CAT) for applications in which it is preferable to administer a test at the level of item sets (i.e., modules). As with CAT, the simulation technique in MST plays a critical role in the development and maintenance of tests. "MSTGen," a new MST…

  12. Outlier Detection in High-Stakes Certification Testing. Research Report.

    ERIC Educational Resources Information Center

    Meijer, Rob R.

    Recent developments of person-fit analysis in computerized adaptive testing (CAT) are discussed. Methods from statistical process control are presented that have been proposed to classify an item score pattern as fitting or misfitting the underlying item response theory (IRT) model in a CAT. Most person-fit research in CAT is restricted to…

  13. Sensitivity to Change of a Computer Adaptive Testing Instrument for Outcome Measurement After Hip and Knee Arthroplasty and Periacetabular Osteotomy.

    PubMed

    McDonough, Christine M; Stoiber, Eva; Tomek, Ivan M; Ni, Pengsheng; Kim, Young-Jo; Tian, Feng; Jette, Alan M

    Study Design Clinical measurement study. Background Computer adaptive testing (CAT) methods may allow detection of change across the continuum of osteoarthritis (OA) care. Objective To evaluate the sensitivity to change of a self-report OA CAT instrument (OA-CAT) following surgery. Methods Core measures consisted of the 5-item OA-CAT function, pain, and disability scales; the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC); the University of California at Los Angeles activity rating scale; and the Medical Outcomes Study 12-Item Short-Form Health Survey (SF-12), which were administered in 3 samples. Fifty-three patients with hip dysplasia completed the core measures, the Hip disability and Osteoarthritis Outcome Score physical function short form (HOOS-PS), and the Modified Harris Hip Score (MHHS) before periacetabular osteotomy, and at 6 months, 1 year, and 2 years after periacetabular osteotomy. The hip (n = 62) and knee (n = 66) arthroplasty samples completed core measures and the MHHS or the Knee Society's Knee Scoring System at baseline and at 3-month follow-up. Mean change, floor and ceiling effects (percent), and effect size were calculated. Results For osteotomy, the 6-month physical function effect sizes for the OA-CAT, WOMAC, HOOS-PS, MHHS, and SF-12 physical component summary scores were 0.66 (95% confidence interval [CI]: 0.08, 1.61), 0.78 (95% CI: 0.56, 1.10), 0.91 (95% CI: 0.70, 1.21), 0.64 (95% CI: 0.22, 1.07), and 0.87 (95% CI: 0.53, 1.38), respectively. Effect-size trends were all increased at 1 year, and most were level at 2 years. For hip arthroplasty, the OA-CAT, WOMAC, MHHS, and SF-12 effect sizes were 1.27 (95% CI: 0.88, 1.84), 1.50 (95% CI: 1.20, 1.80), 0.68 (95% CI: 0.35, 1.04), and 0.56 (95% CI: 0.29, 0.88), respectively. For knee arthroplasty, the OA-CAT, WOMAC, Knee Society Knee Scoring System, and SF-12 effect sizes were 0.81 (95% CI: 0.56, 1.14), 0.85 (95% CI: 0.61, 1.10), 0.09 (95% CI: -0.22, 0.40), and -0.01 (95

  14. SIMPOLYCAT: An SAS Program for Conducting CAT Simulation Based on Polytomous IRT Models

    PubMed Central

    Chen, Ssu-Kuang; Cook, Karon F.

    2009-01-01

    A real-data simulation of computerized adaptive testing (CAT) is an important step in real life CAT applications. Such a simulation allows CAT developers to evaluate important features of the CAT system such as item selection and stopping rules before live testing. SIMPOLYCAT, an SAS macro program, was created by the authors to conduct real-data CAT simulation based on polytomous item response theory (IRT) models. In SIMPOLYCAT, item responses can be input from an external file or generated internally based on item parameters provided by users. The program allows users to choose among methods of setting initial θ, approaches to item selection, trait estimators, CAT stopping criteria, polytomous IRT models, and other CAT parameters. In addition, CAT simulation results can be saved easily and used for further study. The purpose of this article is to introduce SIMPOLYCAT, briefly describe the program algorithm and parameters, and provide examples of CAT simulations using generated and real data. Visual comparisons of the results obtained from the CAT simulations are presented. PMID:19363190

  15. Adapting Tests for Use in Multiple Languages and Cultures. Laboratory of Psychometric and Evaluative Research Report.

    ERIC Educational Resources Information Center

    Hambleton, Ronald K.; Patsula, Liane

    Whatever the purpose of test adaptation, questions arise concerning the validity of inferences from such adapted tests. This paper considers several advantages and disadvantages of adapting tests from one language and culture to another. The paper also reviews several sources of error or invalidity associated with adapting tests and suggests ways…

  16. Approaching sign language test construction: adaptation of the German sign language receptive skills test.

    PubMed

    Haug, Tobias

    2011-01-01

    There is a current need for reliable and valid test instruments in different countries in order to monitor deaf children's sign language acquisition. However, very few tests are commercially available that offer strong evidence for their psychometric properties. A German Sign Language (DGS) test focusing on linguistic structures that are acquired in preschool- and school-aged children (4-8 years old) is urgently needed. Using the British Sign Language Receptive Skills Test, that has been standardized and has sound psychometric properties, as a template for adaptation thus provides a starting point for tests of a sign language that is less documented, such as DGS. This article makes a novel contribution to the field by examining linguistic, cultural, and methodological issues in the process of adapting a test from the source language to the target language. The adapted DGS test has sound psychometric properties and provides the basis for revision prior to standardization.

  17. Testing for local adaptation in brown trout using reciprocal transplants

    PubMed Central

    2012-01-01

    Background Local adaptation can drive the divergence of populations but identification of the traits under selection remains a major challenge in evolutionary biology. Reciprocal transplant experiments are ideal tests of local adaptation, yet rarely used for higher vertebrates because of the mobility and potential invasiveness of non-native organisms. Here, we reciprocally transplanted 2500 brown trout (Salmo trutta) embryos from five populations to investigate local adaptation in early life history traits. Embryos were bred in a full-factorial design and raised in natural riverbeds until emergence. Customized egg capsules were used to simulate the natural redd environment and allowed tracking the fate of every individual until retrieval. We predicted that 1) within sites, native populations would outperform non-natives, and 2) across sites, populations would show higher performance at ‘home’ compared to ‘away’ sites. Results There was no evidence for local adaptation but we found large differences in survival and hatching rates between sites, indicative of considerable variation in habitat quality. Survival was generally high across all populations (55% ± 3%), but ranged from 4% to 89% between sites. Average hatching rate was 25% ± 3% across populations ranging from 0% to 62% between sites. Conclusion This study provides rare empirical data on variation in early life history traits in a population network of a salmonid, and large-scale breeding and transplantation experiments like ours provide powerful tests for local adaptation. Despite the recently reported genetic and morphological differences between the populations in our study area, local adaptation at the embryo level is small, non-existent, or confined to ecological conditions that our experiment could not capture. PMID:23249365

  18. Evaluation of a canine C6 ELISA Lyme disease test for the determination of the infection status of cats naturally exposed to Borrelia burgdorferi.

    PubMed

    Levy, Steven A; O'Connor, Thomas P; Hanscom, Jancy L; Shields, Paulette

    2003-01-01

    The efficacy of a commercially available in-office kit (SNAP 3Dx, IDEXX Laboratories) for detection of antibodies directed against an invariable region (IR6) of the B. burgdorferi surface protein VlsE (Vmp-like sequence, Expressed), a surface antigen of the spirochete recognized during active infection has been evaluated in dogs. The present study was conducted to determine whether this in-office test could be useful for detection of antibodies to B. burgdorferi in cats. Cats owned by clients of a veterinary hospital located in an area hyperendemic for Lyme disease were included in the study. When possible, cats with an outdoor lifestyle, bite wounds, or current tick infestation were recruited for the study to help ensure that animals with a likelihood of exposure to natural infection by B. burgdorferi would be included in the test group. Of the 24 cats tested, 17 samples were positive for antibodies to B. burgdorferi by the C6 ELISA kit. For all 17 of these samples, a duplicate sample tested by immunofluorescent assay (IFA) was in agreement with the ELISA. Five samples were negative by both assays. Two samples that were negative by the C6 ELISA test had low IFA titers (1:100). One of these two discrepant samples was negative and one was positive for antibodies to B. burgdorferi by the Western blot test. It was concluded that the C6 ELISA test performed with good agreement with the IFA and Western blot tests for detection of antibody to B. burgdorferi in the majority of cats tested. The test offers the advantages of producing a result rapidly (approximately 8 minutes), and it requires only two drops of serum, plasma, or whole blood.

  19. Adaptive Set-Based Methods for Association Testing.

    PubMed

    Su, Yu-Chen; Gauderman, William James; Berhane, Kiros; Lewinger, Juan Pablo

    2016-02-01

    With a typical sample size of a few thousand subjects, a single genome-wide association study (GWAS) using traditional one single nucleotide polymorphism (SNP)-at-a-time methods can only detect genetic variants conferring a sizable effect on disease risk. Set-based methods, which analyze sets of SNPs jointly, can detect variants with smaller effects acting within a gene, a pathway, or other biologically relevant sets. Although self-contained set-based methods (those that test sets of variants without regard to variants not in the set) are generally more powerful than competitive set-based approaches (those that rely on comparison of variants in the set of interest with variants not in the set), there is no consensus as to which self-contained methods are best. In particular, several self-contained set tests have been proposed to directly or indirectly "adapt" to the a priori unknown proportion and distribution of effects of the truly associated SNPs in the set, which is a major determinant of their power. A popular adaptive set-based test is the adaptive rank truncated product (ARTP), which seeks the set of SNPs that yields the best-combined evidence of association. We compared the standard ARTP, several ARTP variations we introduced, and other adaptive methods in a comprehensive simulation study to evaluate their performance. We used permutations to assess significance for all the methods and thus provide a level playing field for comparison. We found the standard ARTP test to have the highest power across our simulations followed closely by the global model of random effects (GMRE) and a least absolute shrinkage and selection operator (LASSO)-based test.

  20. Giardia infection in cats.

    PubMed

    Janeczko, Stephanie; Griffin, Brenda

    2010-08-01

    The protozoon Giardia duodenalis is a common gastrointestinal parasite of cats. While most Giardia-infected cats are asymptomatic, acute small bowel diarrhea, occasionally with concomitant weight loss, may occur. Giardia poses a diagnostic challenge, but newer tests, including a commercially available ELISA kit, have improved clinicians' ability to obtain an accurate diagnosis. Several treatment options have been reported, and although none has been shown to be universally effective, most cases can be successfully managed with drug therapy, supportive measures, and environmental control. Current recommendations suggest that combination therapy with fenbendazole and metronidazole may be the safest, most effective treatment option for symptomatic cats.

  1. Adaptive Test Schemes for Control of Paratuberculosis in Dairy Cows

    PubMed Central

    Græsbøll, Kaare; Nielsen, Søren Saxmose; Christiansen, Lasse Engbo; Toft, Nils; Halasa, Tariq

    2016-01-01

    Paratuberculosis is a chronic infection that in dairy cattle causes reduced milk yield, weight loss, and ultimately fatal diarrhea. Subclinical animals can excrete bacteria (Mycobacterium avium ssp. paratuberculosis, MAP) in feces and infect other animals. Farmers identify the infectious animals through a variety of test-strategies, but are challenged by the lack of perfect tests. Frequent testing increases the sensitivity but the costs of testing are a cause of concern for farmers. Here, we used a herd simulation model using milk ELISA tests to evaluate the epidemiological and economic consequences of continuously adapting the sampling interval in response to the estimated true prevalence in the herd. The key results were that the true prevalence was greatly affected by the hygiene level and to some extent by the test-frequency. Furthermore, the choice of prevalence that will be tolerated in a control scenario had a major impact on the true prevalence in the normal hygiene setting, but less so when the hygiene was poor. The net revenue is not greatly affected by the test-strategy, because of the general variation in net revenues between farms. An exception to this is the low hygiene herd, where frequent testing results in lower revenue. When we look at the probability of eradication, then it is correlated with the testing frequency and the target prevalence during the control phase. The probability of eradication is low in the low hygiene herd, and a test-and-cull strategy should probably not be the primary strategy in this herd. Based on this study we suggest that, in order to control MAP, the standard Danish dairy farm should use an adaptive strategy where a short sampling interval of three months is used when the estimated true prevalence is above 1%, and otherwise use a long sampling interval of one year. PMID:27907192

  2. Cat Batiks.

    ERIC Educational Resources Information Center

    Buban, Marcia H.

    1998-01-01

    Discusses an art activity where fourth-grade students created backgrounds using melted paraffin and a variety of paints for their cat batik/collage. Explains that after the students created their backgrounds, they assembled their paper cats for the collage using smaller shapes glued together and wax to add texture for fur. (CMK)

  3. A Hybrid of a CBT- and a CAT-based New English Placement Test Online (NEPTON)

    ERIC Educational Resources Information Center

    Papadima-Sophocleous, Salomi

    2008-01-01

    In recent years, many tertiary institutions have been changing their pen-and-paper English placement test practices into computer based ones. In the process of constructing the University of Nicosia (Intercollege) New English Placement Test Online (NEPTON), we discovered how to redesign our test to include the use of technology. The present…

  4. A Randomized Experiment to Compare Conventional, Computerized, and Computerized Adaptive Administration of Ordinal Polytomous Attitude Items

    ERIC Educational Resources Information Center

    Hol, A. Michiel; Vorst, Harrie C. M.; Mellenbergh, Gideon J.

    2005-01-01

    A total of 520 high school students were randomly assigned to a paper-and-pencil test (PPT), a computerized standard test (CST), or a computerized adaptive test (CAT) version of the Dutch School Attitude Questionnaire (SAQ), consisting of ordinal polytomous items. The CST administered items in the same order as the PPT. The CAT administered all…

  5. Interferometric homogeneity test using adaptive frequency comb illumination.

    PubMed

    Mantel, Klaus; Schwider, Johannes

    2013-03-20

    The homogeneity test of glass plates in a Fizeau interferometer requires the measurement of the glass sample in reflected as well as in transmitted light. For the measurement in transmitted light, the sample has to be inserted into the ray path of a Fizeau or Twyman-Green interferometer, which leads to a nested cavity setup. To separate the interference signals from the different cavities, we illuminate a Fizeau interferometer with an adaptive frequency comb. In this way, rigid glass plates can be measured, and linear variations in the homogeneity can also be detected. The adaptive frequency comb is provided by a variable Fabry-Perot filter under broadband illumination from a superluminescence diode. Compared to approaches using a two-beam interferometer as a filter for the broadband light source, the visibility of the fringe system is considerably higher.

  6. Adaptation to Room Acoustics Using the Modified Rhyme Test

    PubMed Central

    Brandewie, Eugene; Zahorik, Pavel

    2012-01-01

    The negative effect of reverberant sound energy on speech intelligibility is well documented. Recently, however, prior exposure to room acoustics has been shown to increase intelligibility for a number of listeners in simulated room environments. This room adaptation effect, a possible extension of dynamic echo suppression, has been shown to be specific to reverberant rooms and requires binaural input. Because this effect has been demonstrated only using the Coordinated Response Measure (CRM) corpus it is important to determine whether the increase in intelligibility scores reported previously was due to the specific nature of the CRM task. Here we demonstrate a comparable room-acoustic effect using the Modified Rhyme Test (MRT) corpus in multiple room environments. The results are consistent with the idea that the room adaptation effect may be a natural phenomenon of listening in reverberant environments. PMID:23437415

  7. Modeling Student Test-Taking Motivation in the Context of an Adaptive Achievement Test

    ERIC Educational Resources Information Center

    Wise, Steven L.; Kingsbury, G. Gage

    2016-01-01

    This study examined the utility of response time-based analyses in understanding the behavior of unmotivated test takers. For the data from an adaptive achievement test, patterns of observed rapid-guessing behavior and item response accuracy were compared to the behavior expected under several types of models that have been proposed to represent…

  8. Validation of the modified agglutination test for the detection of Toxoplasma gondii in free-range chickens by using cat and mouse bioassay.

    PubMed

    Dubey, J P; Laurin, E; Kwowk, O C H

    2016-03-01

    The modified agglutination test (MAT) is one of the most commonly used tests for the detection of antibodies to Toxoplasma gondii in animal and human sera. The objective of the present study was to evaluate the diagnostic accuracy of the MAT and bioassay in free-range/backyard (FR) chickens (Gallus domesticus). Previously-published T. gondii test results from 2066 chickens from 19 countries were compiled for the present study. The frequency of isolation of T. gondii increased for MAT titres between 1:5 and 1:160, and ranged from 61 to 75% for antibody titres of 1:160, 1:320, and ⩾1:640. Twenty-three cats fed pooled hearts from a total of 802 FR seronegative (MAT, <1:5) chickens from several countries did not excrete oocysts, indicating a high negative predictive value of MAT because FR chickens would have been exposed to many microbes; cats are the most sensitive indicators of T. gondii infection in tissues and can excrete millions of oocysts after ingesting even a few bradyzoites. Of the 29 cats in this study, six cats, fed hearts pooled from 15-122 FR chickens, excreted oocysts; but these identifications were likely related to misidentification or prozone. Results of the present study support the validity of MAT for the detection of T. gondii infection in chickens.

  9. [Prevalence of Tritrichomonas foetus among Dutch cats].

    PubMed

    van Doorn, D C K; de Bruin, M J; Jorritsma, R A; Ploeger, H W; Schoormans, A

    2009-09-01

    Prevalence of Tritrichomonas foetus among Dutch cats The aim of this study was to determine the prevalence of and risk factors for, Tritrichomonas foetus among cats in the Netherlands. A total of 154 faecal samples were collected from three groups of cats: cats with diarrhoea (n=53), cattery cats (n=47), and healthy pet cats (n=54). Faecal samples were examined with a T. foetus specific real-time PCR. All PCR-positive samples were run on gel electrophoresis for definitive diagnosis. The prevalence of T. foetus was 2% among cats with diarrhoea and 4% among cattery cats; T. foetus was not prevalent among pet cats (none of the samples tested positive). Questionnaires had been distributed to cat and cattery owners to determine risk factors for T. foetus, but the low prevalence precluded statistical analysis of the questionnaire results.

  10. Igniter adapter-to-igniter chamber deflection test

    NASA Technical Reports Server (NTRS)

    Cook, M.

    1990-01-01

    Testing was performed to determine the maximum RSRM igniter adapter-to-igniter chamber joint deflection at the crown of the inner joint primary seal. The deflection data was gathered to support igniter inner joint gasket resiliency predictions which led to launch commit criteria temperature determinations. The proximity (deflection) gage holes for the first test (Test No. 1) were incorrectly located; therefore, the test was declared a non-test. Prior to Test No. 2, test article configuration was modified with the correct proximity gage locations. Deflection data were successfully acquired during Test No. 2. However, the proximity gage deflection measurements were adversely affected by temperature increases. Deflections measured after the temperature rise at the proximity gages were considered unreliable. An analysis was performed to predict the maximum deflections based on the reliable data measured before the detectable temperature rise. Deflections to the primary seal crown location were adjusted to correspond to the time of maximum expected operating pressure (2,159 psi) to account for proximity gage bias, and to account for maximum attach and special bolt relaxation. The maximum joint deflection for the igniter inner joint at the crown of the primary seal, accounting for all significant correction factors, was 0.0031 in. (3.1 mil). Since the predicted (0.003 in.) and tested maximum deflection values were sufficiently close, the launch commit criteria was not changed as a result of this test. Data from this test should be used to determine if the igniter inner joint gasket seals are capable of maintaining sealing capability at a joint displacement of (1.4) x (0.0031 in.) = 0.00434 inches. Additional testing should be performed to increase the database on igniter deflections and address launch commit criteria temperatures.

  11. Adaptive modification of the cats vestibulospinal reflex during sustained and combined roll tilt of the whole animal and forepaw rotation: cerebellar mechanisms.

    PubMed

    Andre, P; Pompeiano, O; Manzoni, D

    2005-01-01

    In decerebrate cats, the electromyogram (EMG) activity of the forelimb extensor triceps brachii (TB) increases during side-down roll tilt of the whole animal (vestibulospinal reflex, VSR) at about 0.15 Hz. (+/-10 degrees ), while decreases during side up tilt. On the other hand, the TB activity increases during dorsal flexion of the ipsilateral forepaw (0.15 Hz, +/-5 degrees-10 degrees ), but decreases during ventral flexion. In six experiments, these stimuli were synergistically associated (side-down tilt coincided with dorsal flexion of the forepaw), so that the EMG modulation of the TB activity was greater than that induced by the individual stimuli. During a 3-h period of this sustained stimulation, the amplitude of the pure VSR progressively increased to reach the maximum value at the end of the third hour and persisted unmodified during the post-adaptation period (1 h). In three experiments, animal tilt and forepaw rotation were antagonistically associated (side-down tilt coincided with ventral flexion of the forepaw). In these instances the VSR gain remained on the average stable, but, at the end of the 3-h period of combined stimulation, a proportion of TB responses to animal tilt showed a phase reversal. In a digitigrade animal like the cat, a dorsal flexion of the wrist is associated with a decrease in limb length and would occur when the extensor tone is not appropriate to support body weight; we propose, therefore, that somatosensory volleys elicited by wrist rotation modify the gain of VSR so as to maintain postural stability. Inactivation, on the side of muscle recording, of the corticocerebellar region which projects to the lateral vestibular nucleus of Deiters, by local microinjection of the GABA-A agonist muscimol (0.5 microl at 16 microg/microl), decreased the already adapted gain of VSR. In conclusion, the results of this study suggest that somatosensory reafferent inputs to the cerebellar vermis are used to plastically modify the gain of VSR

  12. Testing the Apodized Pupil Lyot Coronagraph on the Laboratory for Adaptive Optics Extreme Adaptive Optics Testbed

    NASA Astrophysics Data System (ADS)

    Thomas, Sandrine J.; Soummer, Rémi; Dillon, Daren; Macintosh, Bruce; Gavel, Donald; Sivaramakrishnan, Anand

    2011-10-01

    We present testbed results of the Apodized Pupil Lyot Coronagraph (APLC) at the Laboratory for Adaptive Optics (LAO). These results are part of the validation and tests of the coronagraph and of the Extreme Adaptive Optics (ExAO) for the Gemini Planet Imager (GPI). The apodizer component is manufactured with a halftone technique using black chrome microdots on glass. Testing this APLC (like any other coronagraph) requires extremely good wavefront correction, which is obtained to the 1 nm rms level using the microelectricalmechanical systems (MEMS) technology, on the ExAO visible testbed of the LAO at the University of Santa Cruz. We used an APLC coronagraph without central obstruction, both with a reference super-polished flat mirror and with the MEMS to obtain one of the first images of a dark zone in a coronagraphic image with classical adaptive optics using a MEMS deformable mirror (without involving dark hole algorithms). This was done as a complementary test to the GPI coronagraph testbed at American Museum of Natural History, which studied the coronagraph itself without wavefront correction. Because we needed a full aperture, the coronagraph design is very different from the GPI design. We also tested a coronagraph with central obstruction similar to that of GPI. We investigated the performance of the APLC coronagraph and more particularly the effect of the apodizer profile accuracy on the contrast. Finally, we compared the resulting contrast to predictions made with a wavefront propagation model of the testbed to understand the effects of phase and amplitude errors on the final contrast.

  13. TESTING THE APODIZED PUPIL LYOT CORONAGRAPH ON THE LABORATORY FOR ADAPTIVE OPTICS EXTREME ADAPTIVE OPTICS TESTBED

    SciTech Connect

    Thomas, Sandrine J.; Dillon, Daren; Gavel, Donald; Macintosh, Bruce; Sivaramakrishnan, Anand E-mail: dillon@ucolick.org E-mail: soummer@stsci.edu E-mail: anand@amnh.org

    2011-10-15

    We present testbed results of the Apodized Pupil Lyot Coronagraph (APLC) at the Laboratory for Adaptive Optics (LAO). These results are part of the validation and tests of the coronagraph and of the Extreme Adaptive Optics (ExAO) for the Gemini Planet Imager (GPI). The apodizer component is manufactured with a halftone technique using black chrome microdots on glass. Testing this APLC (like any other coronagraph) requires extremely good wavefront correction, which is obtained to the 1 nm rms level using the microelectricalmechanical systems (MEMS) technology, on the ExAO visible testbed of the LAO at the University of Santa Cruz. We used an APLC coronagraph without central obstruction, both with a reference super-polished flat mirror and with the MEMS to obtain one of the first images of a dark zone in a coronagraphic image with classical adaptive optics using a MEMS deformable mirror (without involving dark hole algorithms). This was done as a complementary test to the GPI coronagraph testbed at American Museum of Natural History, which studied the coronagraph itself without wavefront correction. Because we needed a full aperture, the coronagraph design is very different from the GPI design. We also tested a coronagraph with central obstruction similar to that of GPI. We investigated the performance of the APLC coronagraph and more particularly the effect of the apodizer profile accuracy on the contrast. Finally, we compared the resulting contrast to predictions made with a wavefront propagation model of the testbed to understand the effects of phase and amplitude errors on the final contrast.

  14. Multidimensional CAT Item Selection Methods for Domain Scores and Composite Scores: Theory and Applications

    ERIC Educational Resources Information Center

    Yao, Lihua

    2012-01-01

    Multidimensional computer adaptive testing (MCAT) can provide higher precision and reliability or reduce test length when compared with unidimensional CAT or with the paper-and-pencil test. This study compared five item selection procedures in the MCAT framework for both domain scores and overall scores through simulation by varying the structure…

  15. Reading Test-Sentence Comprehension: An Adapted Version of Lobrot's Lecture 3 Test for Brazilian Portuguese.

    PubMed

    de Araújo Vilhena, Douglas; Sucena, Ana; Castro, São Luís; Pinheiro, Ângela Maria Vieira

    2016-02-01

    Our aim was to analyse the linguistic structure of the Lobrot's Lecture 3 (L3) reading test and to describe the procedure for its adaptation to a Brazilian cultural-linguistic context. The resulting adapted version is called the Reading Test-Sentence Comprehension [Teste de Leitura: Compreensão de Sentenças (TELCS)] and was developed using the European Portuguese adaptation of L3 as a reference. The present study was conducted in seven steps: (1) classification of the response alternatives of L3 test; (2) adaptation of the original sentences into Brazilian Portuguese; (3) back-translation; (4) adaptation of the distractors from TELCS; (5) configuration of TELCS; (6) pilot study; and (7) validation and standardization. In comparison with L3, TELCS included new linguistic and structural variables, such as frequency of occurrence of the distractors, gender neutrality and position of the target words. The instrument can be used for a collective screening or individual clinical administration purposes to evaluate the reading ability of second-to-fifth-grade and 7-to-11-year-old students.

  16. Astronomy CATS

    NASA Astrophysics Data System (ADS)

    Brissenden, Gina; Prather, Edward E.; Impey, Chris

    2012-08-01

    The Center for Astronomy Education's (CAE's) NSF-funded Collaboration of Astronomy Teaching Scholars (CATS) Program is a grassroots multi-institutional effort to increase the capacity for astronomy education research and improve science literacy in the United States.Our primary target population is the 500,000 college students who each year enroll in an introductory general education (a breadth requirement for non-science majors) Earth, Astronomy, and Space Science (EASS) course (Fraknoi 2001, AGI 2006).An equally important population for our efforts is the individuals who are, or will be, teaching these students. In this chapter, we will briefly discuss the goals of CAE and CATS, the varied personnel that make up the CATS collective, the diverse projects we've undertaken, and the many challenges we have had to work through to make CATS a success.

  17. Dynamic Assessment of Health Outcomes: Time to Let the CAT Out of the Bag?

    PubMed Central

    Cook, Karon F; O'Malley, Kimberly J; Roddey, Toni S

    2005-01-01

    Background The use of item response theory (IRT) to measure self-reported outcomes has burgeoned in recent years. Perhaps the most important application of IRT is computer-adaptive testing (CAT), a measurement approach in which the selection of items is tailored for each respondent. Objective To provide an introduction to the use of CAT in the measurement of health outcomes, describe several IRT models that can be used as the basis of CAT, and discuss practical issues associated with the use of adaptive scaling in research settings. Principal Points The development of a CAT requires several steps that are not required in the development of a traditional measure including identification of “starting” and “stopping” rules. CAT's most attractive advantage is its efficiency. Greater measurement precision can be achieved with fewer items. Disadvantages of CAT include the high cost and level of technical expertise required to develop a CAT. Conclusions Researchers, clinicians, and patients benefit from the availability of psychometrically rigorous measures that are not burdensome. CAT outcome measures hold substantial promise in this regard, but their development is not without challenges. PMID:16179003

  18. An Adaptive Genetic Association Test Using Double Kernel Machines.

    PubMed

    Zhan, Xiang; Epstein, Michael P; Ghosh, Debashis

    2015-10-01

    Recently, gene set-based approaches have become very popular in gene expression profiling studies for assessing how genetic variants are related to disease outcomes. Since most genes are not differentially expressed, existing pathway tests considering all genes within a pathway suffer from considerable noise and power loss. Moreover, for a differentially expressed pathway, it is of interest to select important genes that drive the effect of the pathway. In this article, we propose an adaptive association test using double kernel machines (DKM), which can both select important genes within the pathway as well as test for the overall genetic pathway effect. This DKM procedure first uses the garrote kernel machines (GKM) test for the purposes of subset selection and then the least squares kernel machine (LSKM) test for testing the effect of the subset of genes. An appealing feature of the kernel machine framework is that it can provide a flexible and unified method for multi-dimensional modeling of the genetic pathway effect allowing for both parametric and nonparametric components. This DKM approach is illustrated with application to simulated data as well as to data from a neuroimaging genetics study.

  19. Development and field testing of an adaptive power factor controller

    SciTech Connect

    El-Sharkawi, M.; Venkata, S.S.; Butler, N.G.; Yinger, R.W.

    1987-12-01

    The Adaptive Power Factor Controller (APFC) is a device that switches capacitors electronically to achieve almost unity power factor at the point of installation. It was designed and developed at the University of Washington (UW), and is being tested at the R and D facility of the Southern California Edison Company (SCE). It is particularly intended for loads with dynamically varying reactive power demands such as induction generators in wind power stations, or cyclically changing loads such as induction motors in process industries. It is also ideally suited for improving the power factor profile of a distribution line. The purposes of this paper are two-fold: to explain the most recent design of the 50-kVAR APFC and to report the results of the field testing program on the device after it was installed at the terminals of a 50-kW three-phase induction generator located at the Dever Wind R and D site of SCE.

  20. Design of the Dual Conjugate Adaptive Optics Test-bed

    NASA Astrophysics Data System (ADS)

    Sharf, Inna; Bell, K.; Crampton, D.; Fitzsimmons, J.; Herriot, Glen; Jolissaint, Laurent; Lee, B.; Richardson, H.; van der Kamp, D.; Veran, Jean-Pierre

    In this paper, we describe the Multi-Conjugate Adaptive Optics laboratory test-bed presently under construction at the University of Victoria, Canada. The test-bench will be used to support research in the performance of multi-conjugate adaptive optics, turbulence simulators, laser guide stars and miniaturizing adaptive optics. The main components of the test-bed include two micro-machined deformable mirrors, a tip-tilt mirror, four wavefront sensors, a source simulator, a dual-layer turbulence simulator, as well as computational and control hardware. The paper will describe in detail the opto-mechanical design of the adaptive optics module, the design of the hot-air turbulence generator and the configuration chosen for the source simulator. Below, we present a summary of these aspects of the bench. The optical and mechanical design of the test-bed has been largely driven by the particular choice of the deformable mirrors. These are continuous micro-machined mirrors manufactured by Boston Micromachines Corporation. They have a clear aperture of 3.3 mm and are deformed with 140 actuators arranged in a square grid. Although the mirrors have an open-loop bandwidth of 6.6 KHz, their shape can be updated at a sampling rate of 100 Hz. In our optical design, the mirrors are conjugated at 0km and 10 km in the atmosphere. A planar optical layout was achieved by using four off-axis paraboloids and several folding mirrors. These optics will be mounted on two solid blocks which can be aligned with respect to each other. The wavefront path design accommodates 3 monochromatic guide stars that can be placed at either 90 km or at infinity. The design relies on the natural separation of the beam into 3 parts because of differences in locations of the guide stars in the field of view. In total four wavefront sensors will be procured from Adaptive Optics Associates (AOA) or built in-house: three for the guide stars and the fourth to collect data from the science source output in

  1. ESO adaptive optics facility progress and first laboratory test results

    NASA Astrophysics Data System (ADS)

    Arsenault, Robin; Madec, Pierre-Yves; Paufique, Jérome; La Penna, Paolo; Stroebele, Stefan; Vernet, Elise; Pirard, Jean-Francois; Hackenberg, Wolfgang; Kuntschner, Harald; Kolb, Johann; Muller, Nicolas; Garcia-Rissmann, Aurea; Le Louarn, Miska; Amico, Paola; Hubin, Norbert; Lizon, Jean-Louis; Ridings, Rob; Haguenauer, Pierre; Abad, Jose A.; Fischer, Gerhard; Heinz, Volker; Kiekebusch, Mario; Argomedo, Javier; Conzelmann, Ralf; Tordo, Sebastien; Donaldson, Rob; Soenke, Christian; Duhoux, Philippe; Fedrigo, Enrico; Delabre, Bernard; Jost, Andrea; Duchateau, Michel; Downing, Mark; Reyes Moreno, Javier; Manescau, Antonio; Bonaccini Calia, Domenico; Quattri, Marco; Dupuy, Christophe; Guidolin, Ivan M.; Comin, Mauro; Guzman, Ronald; Buzzoni, Bernard; Quentin, Jutta; Lewis, Steffan; Jolley, Paul; Kraus, Max; Pfrommer, Thomas; Biasi, Roberto; Gallieni, Daniele; Stuik, Remko; Kaenders, Wilhelm; Ernstberger, Bernhard; Friedenauer, Axel

    2014-07-01

    The Adaptive Optics Facility project is completing the integration of its systems at ESO Headquarters in Garching. The main test bench ASSIST and the 2nd Generation M2-Unit (hosting the Deformable Secondary Mirror) have been granted acceptance late 2012. The DSM has undergone a series of tests on ASSIST in 2013 which have validated its optical performance and launched the System Test Phase of the AOF. This has been followed by the performance evaluation of the GRAAL natural guide star mode on-axis and will continue in 2014 with its Ground Layer AO mode. The GALACSI module (for MUSE) Wide-Field-Mode (GLAO) and the more challenging Narrow-Field-Mode (LTAO) will then be tested. The AOF has also taken delivery of the second scientific thin shell mirror and the first 22 Watt Sodium laser Unit. We will report on the system tests status, the performances evaluated on the ASSIST bench and advancement of the 4Laser Guide Star Facility. We will also present the near future plans for commissioning on the telescope and some considerations on tools to ensure an efficient operation of the Facility in Paranal.

  2. Turning the Page on Pen-and-Paper Questionnaires: Combining Ecological Momentary Assessment and Computer Adaptive Testing to Transform Psychological Assessment in the 21st Century.

    PubMed

    Gibbons, Chris J

    2016-01-01

    The current paper describes new opportunities for patient-centred assessment methods which have come about by the increased adoption of affordable smart technologies in biopsychosocial research and medical care. In this commentary, we review modern assessment methods including item response theory (IRT), computer adaptive testing (CAT), and ecological momentary assessment (EMA) and explain how these methods may be combined to improve psychological assessment. We demonstrate both how a 'naïve' selection of a small group of items in an EMA can lead to unacceptably unreliable assessments and how IRT can provide detailed information on the individual information that each item gives thus allowing short form assessments to be selected with acceptable reliability. The combination of CAT and IRT can ensure assessments are precise, efficient, and well targeted to the individual; allowing EMAs to be both brief and accurate.

  3. Turning the Page on Pen-and-Paper Questionnaires: Combining Ecological Momentary Assessment and Computer Adaptive Testing to Transform Psychological Assessment in the 21st Century

    PubMed Central

    Gibbons, Chris J.

    2017-01-01

    The current paper describes new opportunities for patient-centred assessment methods which have come about by the increased adoption of affordable smart technologies in biopsychosocial research and medical care. In this commentary, we review modern assessment methods including item response theory (IRT), computer adaptive testing (CAT), and ecological momentary assessment (EMA) and explain how these methods may be combined to improve psychological assessment. We demonstrate both how a ‘naïve’ selection of a small group of items in an EMA can lead to unacceptably unreliable assessments and how IRT can provide detailed information on the individual information that each item gives thus allowing short form assessments to be selected with acceptable reliability. The combination of CAT and IRT can ensure assessments are precise, efficient, and well targeted to the individual; allowing EMAs to be both brief and accurate. PMID:28154540

  4. Identifying Differential Item Functioning in Multi-Stage Computer Adaptive Testing

    ERIC Educational Resources Information Center

    Gierl, Mark J.; Lai, Hollis; Li, Johnson

    2013-01-01

    The purpose of this study is to evaluate the performance of CATSIB (Computer Adaptive Testing-Simultaneous Item Bias Test) for detecting differential item functioning (DIF) when items in the matching and studied subtest are administered adaptively in the context of a realistic multi-stage adaptive test (MST). MST was simulated using a 4-item…

  5. Evaluation of three different histamine concentrations in intradermal testing of normal cats and attempted determination of 'irritant' threshold concentrations for 48 allergens.

    PubMed

    Austel, Michaela; Hensel, Patrick; Jackson, Dawn; Vidyashankar, Anand; Zhao, Ying; Medleau, Linda

    2006-06-01

    The purpose of this study was to determine the optimal histamine concentration and 'irritant' allergen threshold concentrations in intradermal testing (IDT) in normal cats. Thirty healthy cats were tested with three different histamine concentrations and four different concentrations of each allergen. The optimal histamine concentration was determined to be 1: 50,000 w/v (0.05 mg mL(-1)). Using this histamine concentration, the 'irritant' threshold concentration for most allergens was above the highest concentrations tested (4,000 PNU mL(-1) for 41 allergens and 700 PNU mL(-1) for human dander). The 'irritant' threshold concentration for flea antigen was determined to be 1:750 w/v. More than 10% of the tested cats showed positive reactions to Dermatophagoides farinae, Dermatophagoides pteronyssinus, housefly, mosquito and moth at every allergen concentration, which suggests that the 'irritant' threshold concentration for these allergens is below 1,000 PNU mL(-1), the lowest allergen concentration tested. Our results confirm previous studies in indicating that allergen and histamine concentrations used in feline IDT may need to be revised.

  6. Determination of feeder cell-based cellular niches supporting the colonization and maintenance of spermatogonial stem cells from prepubertal domestic cat testes.

    PubMed

    Han, N R; Park, Y H; Yun, J I; Park, H J; Park, M H; Kim, M S; Choi, J H; Lee, E; Gong, S P; Lim, J M; Lee, S T

    2014-10-01

    Recently, isolation and in vitro culture of putative spermatogonial stem cells (SSCs) in the domestic cat have been conducted. However, the cellular niche conditions that facilitate the establishment and long-term maintenance of feline SSCs (FSSCs) have not been described. Therefore, we investigated the type of feeder cells used to stimulate colony formation and growth of FSSCs among the various factors in the FSSC niche. Spermatogonial stem cells isolated from feline testes were cultured on mitotically inactivated testicular stromal cells (TSCs) derived from cats, dogs and mice, and mouse embryonic fibroblasts (MEFs). The formation and growth of colonies derived from SSCs cultured on each type of feeder cell were identified at passage 0, and the morphology, alkaline phosphatase (AP) activity and expression of SSC-specific genes in surviving colonies were investigated at passage 4. Among these diverse feeder cells, TSCs from cat showed the greatest colony formation, growth and maintenance of FSSCs, and SSC colonies cultured by passage 4 showed a typical dome-shaped morphology, AP activity and expression of SSC-specific genes (NANOG, OCT4, SOX2 and CD9). Accordingly, these results demonstrate that feline TSCs could be used as feeder cells to support the establishment and maintenance of SSCs from domestic cats.

  7. The calibrated automated thrombogram (CAT): a universal routine test for hyper- and hypocoagulability.

    PubMed

    Hemker, H C; Giesen, P; AlDieri, R; Regnault, V; de Smed, E; Wagenvoord, R; Lecompte, T; Béguin, S

    2002-01-01

    By using a "slow" fluorogenic thrombin substrate and continuous comparison to a simultaneously run calibrator, thrombin generation can be monitored automatically, on line, in clotting PPP or PRP at a throughput of up to 100 samples per hour. The resulting "Thrombogram" in PPP measures hypocoagulability (haemophilias, oral anticoagulants, heparins (-likes), direct inhibitors) and hypercoagulabilities (AT deficiency, prothrombin hyperexpression, prot. C and S deficiency, factor V Leiden, oral contraceptives). In PRP it is diminished in thrombopathies, in von Willebrand disease, by antibodies blocking GPIIb-IIIa or GPIb, or by antiplatelet drugs like aspirin and clopidogrel. Lupus anticoagulant both retards and increases thrombin generation. The thrombogram thus appears to be a broad function test of the haemostatic-thrombotic mechanism of the blood.

  8. Failing Tests: Commentary on "Adapting Educational Measurement to the Demands of Test-Based Accountability"

    ERIC Educational Resources Information Center

    Thissen, David

    2015-01-01

    In "Adapting Educational Measurement to the Demands of Test-Based Accountability" Koretz takes the time-honored engineering approach to educational measurement, identifying specific problems with current practice and proposing minimal modifications of the system to alleviate those problems. In response to that article, David Thissen…

  9. Highly adaptive tests for group differences in brain functional connectivity.

    PubMed

    Kim, Junghi; Pan, Wei

    2015-01-01

    Resting-state functional magnetic resonance imaging (rs-fMRI) and other technologies have been offering evidence and insights showing that altered brain functional networks are associated with neurological illnesses such as Alzheimer's disease. Exploring brain networks of clinical populations compared to those of controls would be a key inquiry to reveal underlying neurological processes related to such illnesses. For such a purpose, group-level inference is a necessary first step in order to establish whether there are any genuinely disrupted brain subnetworks. Such an analysis is also challenging due to the high dimensionality of the parameters in a network model and high noise levels in neuroimaging data. We are still in the early stage of method development as highlighted by Varoquaux and Craddock (2013) that "there is currently no unique solution, but a spectrum of related methods and analytical strategies" to learn and compare brain connectivity. In practice the important issue of how to choose several critical parameters in estimating a network, such as what association measure to use and what is the sparsity of the estimated network, has not been carefully addressed, largely because the answers are unknown yet. For example, even though the choice of tuning parameters in model estimation has been extensively discussed in the literature, as to be shown here, an optimal choice of a parameter for network estimation may not be optimal in the current context of hypothesis testing. Arbitrarily choosing or mis-specifying such parameters may lead to extremely low-powered tests. Here we develop highly adaptive tests to detect group differences in brain connectivity while accounting for unknown optimal choices of some tuning parameters. The proposed tests combine statistical evidence against a null hypothesis from multiple sources across a range of plausible tuning parameter values reflecting uncertainty with the unknown truth. These highly adaptive tests are not only

  10. Highly adaptive tests for group differences in brain functional connectivity

    PubMed Central

    Kim, Junghi; Pan, Wei

    2015-01-01

    Resting-state functional magnetic resonance imaging (rs-fMRI) and other technologies have been offering evidence and insights showing that altered brain functional networks are associated with neurological illnesses such as Alzheimer's disease. Exploring brain networks of clinical populations compared to those of controls would be a key inquiry to reveal underlying neurological processes related to such illnesses. For such a purpose, group-level inference is a necessary first step in order to establish whether there are any genuinely disrupted brain subnetworks. Such an analysis is also challenging due to the high dimensionality of the parameters in a network model and high noise levels in neuroimaging data. We are still in the early stage of method development as highlighted by Varoquaux and Craddock (2013) that “there is currently no unique solution, but a spectrum of related methods and analytical strategies” to learn and compare brain connectivity. In practice the important issue of how to choose several critical parameters in estimating a network, such as what association measure to use and what is the sparsity of the estimated network, has not been carefully addressed, largely because the answers are unknown yet. For example, even though the choice of tuning parameters in model estimation has been extensively discussed in the literature, as to be shown here, an optimal choice of a parameter for network estimation may not be optimal in the current context of hypothesis testing. Arbitrarily choosing or mis-specifying such parameters may lead to extremely low-powered tests. Here we develop highly adaptive tests to detect group differences in brain connectivity while accounting for unknown optimal choices of some tuning parameters. The proposed tests combine statistical evidence against a null hypothesis from multiple sources across a range of plausible tuning parameter values reflecting uncertainty with the unknown truth. These highly adaptive tests are not

  11. Design of Sequentially Randomized Trials for Testing Adaptive Treatment Strategies

    PubMed Central

    Ogbagaber, Semhar B.; Karp, Jordan; Wahed, Abdus S.

    2016-01-01

    An adaptive treatment strategy (ATS) is an outcome-guided algorithm that allows personalized treatment of complex diseases based on patients’ disease status and treatment history. Conditions such as AIDS, depression, and cancer usually require several stages of treatment due to the chronic, multifactorial nature of illness progression and management. Sequential multiple assignment randomized (SMAR) designs permit simultaneous inference about multiple ATSs, where patients are sequentially randomized to treatments at different stages depending upon response status. The purpose of the article is to develop a sample size formula to ensure adequate power for comparing two or more ATSs. Based on a Wald-type statistic for comparing multiple ATSs with a continuous endpoint, we develop a sample size formula and test it through simulation studies. We show via simulation that the proposed sample size formula maintains the nominal power. The proposed sample size formula is not applicable to designs with time-to-event endpoints but the formula will be useful for practitioners while designing SMAR trials to compare adaptive treatment strategies. PMID:26412033

  12. Domestic Cats (Felis silvestris catus) Do Not Show Signs of Secure Attachment to Their Owners

    PubMed Central

    Potter, Alice; Mills, Daniel Simon

    2015-01-01

    The Ainsworth Strange Situation Test (SST) has been widely used to demonstrate that the bond between both children and dogs to their primary carer typically meets the requirements of a secure attachment (i.e. the carer being perceived as a focus of safety and security in otherwise threatening environments), and has been adapted for cats with a similar claim made. However methodological problems in this latter research make the claim that the cat-owner bond is typically a secure attachment, operationally definable by its behaviour in the SST, questionable. We therefore developed an adapted version of the SST with the necessary methodological controls which include a full counterbalance of the procedure. A cross-over design experiment with 20 cat-owner pairs (10 each undertaking one of the two versions of the SST first) and continuous focal sampling was used to record the duration of a range of behavioural states expressed by the cats that might be useful for assessing secure attachment. Since data were not normally distributed, non-parametric analyses were used on those behaviours shown to be reliable across the two versions of the test (which excluded much cat behaviour). Although cats vocalised more when the owner rather the stranger left the cat with the other individual, there was no other evidence consistent with the interpretation of the bond between a cat and its owner meeting the requirements of a secure attachment. These results are consistent with the view that adult cats are typically quite autonomous, even in their social relationships, and not necessarily dependent on others to provide a sense of security and safety. It is concluded that alternative methods need to be developed to characterise the normal psychological features of the cat-owner bond. PMID:26332470

  13. Hearing disorders in cats.

    PubMed

    Strain, George M

    2017-03-01

    Practical relevance: Auditory function is a sense that is central to life for cats - being important in situational awareness of potential predators, pursuit of prey, and for communication with conspecifics, humans and other species. Deafness in cats is most frequently the result of a genetic disorder, strongly associated with white fur and blue eyes, but may also result from acquired causes such as advancing age, ototoxic drugs, infection, environmental noise and physical trauma. Deafness can be sensorineural, where there is loss of cochlear hair cells, or conductive, where sound is muffled on its way to the inner ear. Clinical challenges: Establishing whether a cat is deaf can be difficult as behavioral testing of hearing is subjective and does not reliably detect unilateral deafness. Brainstem auditory evoked response testing is an objective measure but is limited in its availability. Currently, sensorineural deafness is irreversible because no treatments are available to restore lost hair cells. Conductive hearing loss can usually be treated, although full hearing recovery following otitis media may take weeks as the body clears the middle ear of debris. Evidence base: The author draws on the published literature and his extensive research on clinical aspects and molecular genetics of deafness, principally in companion animals, to review types and forms of deafness in cats. He also discusses current diagnostic approaches and provides brief advice for managing cats with hearing loss.

  14. Design, realization and structural testing of a compliant adaptable wing

    NASA Astrophysics Data System (ADS)

    Molinari, G.; Quack, M.; Arrieta, A. F.; Morari, M.; Ermanni, P.

    2015-10-01

    This paper presents the design, optimization, realization and testing of a novel wing morphing concept, based on distributed compliance structures, and actuated by piezoelectric elements. The adaptive wing features ribs with a selectively compliant inner structure, numerically optimized to achieve aerodynamically efficient shape changes while simultaneously withstanding aeroelastic loads. The static and dynamic aeroelastic behavior of the wing, and the effect of activating the actuators, is assessed by means of coupled 3D aerodynamic and structural simulations. To demonstrate the capabilities of the proposed morphing concept and optimization procedure, the wings of a model airplane are designed and manufactured according to the presented approach. The goal is to replace conventional ailerons, thus to achieve controllability in roll purely by morphing. The mechanical properties of the manufactured components are characterized experimentally, and used to create a refined and correlated finite element model. The overall stiffness, strength, and actuation capabilities are experimentally tested and successfully compared with the numerical prediction. To counteract the nonlinear hysteretic behavior of the piezoelectric actuators, a closed-loop controller is implemented, and its capability of accurately achieving the desired shape adaptation is evaluated experimentally. Using the correlated finite element model, the aeroelastic behavior of the manufactured wing is simulated, showing that the morphing concept can provide sufficient roll authority to allow controllability of the flight. The additional degrees of freedom offered by morphing can be also used to vary the plane lift coefficient, similarly to conventional flaps. The efficiency improvements offered by this technique are evaluated numerically, and compared to the performance of a rigid wing.

  15. Adaptive structures to enable ground test validation of precision structures

    NASA Technical Reports Server (NTRS)

    Wada, Ben K.; Fanson, James F.; Chen, Gun-Shing; Kuo, Chin-Po

    1990-01-01

    The use of analytical models and ground-based experimental validation of precision space structures is addressed. The application of adaptive structures to such validation of precision space structures is addressed, with the focus on adaptive truss structures.

  16. Cat scratch disease (image)

    MedlinePlus

    Cat scratch disease is an infectious illness associated with cat scratches, bites, or exposure to cat saliva, causing chronic swelling of the lymph nodes. Cat scratch disease is possibly the most common cause of chronic ...

  17. Cat and Dog Bites

    MedlinePlus

    ... Prevention and Wellness Staying Healthy Pets and Animals Cat and Dog Bites Cat and Dog Bites Pets and AnimalsPrevention and WellnessStaying Healthy Share Cat and Dog Bites Cat and dog bites are ...

  18. Differences between vocalization evoked by social stimuli in feral cats and house cats.

    PubMed

    Yeon, Seong C; Kim, Young K; Park, Se J; Lee, Scott S; Lee, Seung Y; Suh, Euy H; Houpt, Katherine A; Chang, Hong H; Lee, Hee C; Yang, Byung G; Lee, Hyo J

    2011-06-01

    To investigate how socialization can affect the types and characteristics of vocalization produced by cats, feral cats (n=25) and house cats (n=13) were used as subjects, allowing a comparison between cats socialized to people and non-socialized cats. To record vocalization and assess the cats' responses to behavioural stimuli, five test situations were used: approach by a familiar caretaker, by a threatening stranger, by a large doll, by a stranger with a dog and by a stranger with a cat. Feral cats showed extremely aggressive and defensive behaviour in most test situations, and produced higher call rates than those of house cats in the test situations, which could be attributed to less socialization to other animals and to more sensitivity to fearful situations. Differences were observed in the acoustic parameters of feral cats in comparison to those of house cats. The feral cat produced significantly higher frequency in fundamental frequency, peak frequency, 1st quartile frequency, 3rd quartile frequency of growls and hisses in agonistic test situations. In contrast to the growls and hisses, in meow, all acoustic parameters like fundamental frequency, first formant, peak frequency, 1st quartile frequency, and 3rd quartile frequency of house cats were of significantly higher frequency than those of feral cats. Also, house cats produced calls of significantly shorter in duration than feral cats in agonistic test situations. These results support the conclusion that a lack of socialization may affect usage of types of vocalizations, and the vocal characteristics, so that the proper socialization of cat may be essential to be a suitable companion house cat.

  19. Squamous cell carcinoma of dogs and cats: an ideal test system for human head and neck PDT protocols

    NASA Astrophysics Data System (ADS)

    Lucroy, Michael D.

    2006-02-01

    Photodynamic therapy (PDT) is ideally suited for the treatment of head and neck cancer (HNC) in humans. Developing useful PDT protocols for HNC is challenging due to the expense of Phase I and II clinical trials. Moreover, the often-poor predictive value of murine models means that photosensitizers may proceed far into development before problems are noted. Dogs and cats with spontaneous oral squamous cell carcinoma (SCC) share striking similarities with humans affected with oral SCC. These similarities include viral and environmental tobacco smoke as risk factors, location-dependent prognoses, and relative resistance to chemotherapy. The relatively large oral cancers encountered in veterinary patients allow for light and drug dosimetry that are directly applicable to humans. The irregular shape of oral SCC allows a rigorous evaluation of novel photodynamic therapy protocols under field conditions. Because spontaneous tumors in dogs and cats arise in an outbred animal population it is possible to observe an intact host response to PDT. The shorter lifespan of dogs and cats allows rapid accrual of endpoint data. External beam radiation therapy and chemotherapy are commonplace in veterinary medicine, making dogs and cats with spontaneous SCC a useful resource to study the interactions with PDT and other cancer treatment modalities. Our preliminary results demonstrate that PDT is well-tolerated by dogs with oral cancer, and a Phase II clinical trial of zinc-phthalocyanine-based photodynamic therapy is underway in dogs with oral SCC. The usefulness of 5-aminolevulinic acid methyl ester-based PDT is being investigated in cats with oral SCC.

  20. Big cat genomics.

    PubMed

    O'Brien, Stephen J; Johnson, Warren E

    2005-01-01

    Advances in population and quantitative genomics, aided by the computational algorithms that employ genetic theory and practice, are now being applied to biological questions that surround free-ranging species not traditionally suitable for genetic enquiry. Here we review how applications of molecular genetic tools have been used to describe the natural history, present status, and future disposition of wild cat species. Insight into phylogenetic hierarchy, demographic contractions, geographic population substructure, behavioral ecology, and infectious diseases have revealed strategies for survival and adaptation of these fascinating predators. Conservation, stabilization, and management of the big cats are important areas that derive benefit from the genome resources expanded and applied to highly successful species, imperiled by an expanding human population.

  1. Examining the Construct Validity of the MMPI-2-RF Interpersonal Functioning Scales Using the Computerized Adaptive Test of Personality Disorder as a Comparative Framework.

    PubMed

    Franz, Annabel O; Harrop, Tiffany M; McCord, David M

    2016-09-23

    This study aimed to examine the construct validity of the Minnesota Multiphasic Personality Inventory-2 Restructured Form (MMPI-2-RF) interpersonal functioning scales (Ben-Porath & Tellegen, 2008/2011 ) using as a criterion measure the Computerized Adaptive Test of Personality Disorder-Static Form (CAT-PD-SF; Simms et al., 2011 ). Participants were college students (n = 98) recruited through the university subject pool. A series of a priori hypotheses were developed for each of the 6 interpersonal functioning scales of the MMPI-2-RF, expressed as predicted correlations with construct-relevant CAT-PD-SF scales. Of the 27 specific predictions, 21 were supported by substantial (≥ |.30|) correlations. The MMPI-2-RF Family Problems scale (FML) demonstrated the strongest correlations with CAT-PD-SF scales Anhedonia and Mistrust; Cynicism (RC3) was most highly correlated with Mistrust and Norm Violation; Interpersonal Passivity (IPP) was most highly correlated with Domineering and Rudeness; Social Avoidance (SAV) was most highly correlated with Social Withdrawal and Anhedonia; Shyness (SHY) was most highly correlated with Social Withdrawal and Anxioiusness; and Disaffiliativeness (DSF) was most highly correlated with Emotional Detachment and Mistrust. Results are largely consistent with hypotheses suggesting support for both models of constructs relevant to interpersonal functioning. Future research designed to more precisely differentiate Social Avoidance (SAV) and Shyness (SHY) is suggested.

  2. Preliminary Report on a National Cross-Validation of the Computerized Adaptive Screening Test (CAST).

    ERIC Educational Resources Information Center

    Knapp, Deirdre J.; Pliske, Rebecca M.

    A study was conducted to validate the Army's Computerized Adaptive Screening Test (CAST), using data from 2,240 applicants from 60 army recruiting stations across the nation. CAST is a computer-assisted adaptive test used to predict performance on the Armed Forces Qualification Test (AFQT). AFQT scores are computed by adding four subtest scores of…

  3. Computerized Dynamic Adaptive Tests with Immediately Individualized Feedback for Primary School Mathematics Learning

    ERIC Educational Resources Information Center

    Wu, Huey-Min; Kuo, Bor-Chen; Wang, Su-Chen

    2017-01-01

    In this study, a computerized dynamic assessment test with both immediately individualized feedback and adaptively property was applied to Mathematics learning in primary school. For evaluating the effectiveness of the computerized dynamic adaptive test, the performances of three types of remedial instructions were compared by a pre-test/post-test…

  4. Evaluating Knowledge Structure-Based Adaptive Testing Algorithms and System Development

    ERIC Educational Resources Information Center

    Wu, Huey-Min; Kuo, Bor-Chen; Yang, Jinn-Min

    2012-01-01

    In recent years, many computerized test systems have been developed for diagnosing students' learning profiles. Nevertheless, it remains a challenging issue to find an adaptive testing algorithm to both shorten testing time and precisely diagnose the knowledge status of students. In order to find a suitable algorithm, four adaptive testing…

  5. USING AN ADAPTER TO PERFORM THE CHALFANT-STYLE CONTAINMENT VESSEL PERIODIC MAINTENANCE LEAK RATE TEST

    SciTech Connect

    Loftin, B.; Abramczyk, G.; Trapp, D.

    2011-06-03

    Recently the Packaging Technology and Pressurized Systems (PT&PS) organization at the Savannah River National Laboratory was asked to develop an adapter for performing the leak-rate test of a Chalfant-style containment vessel. The PT&PS organization collaborated with designers at the Department of Energy's Pantex Plant to develop the adapter currently in use for performing the leak-rate testing on the containment vessels. This paper will give the history of leak-rate testing of the Chalfant-style containment vessels, discuss the design concept for the adapter, give an overview of the design, and will present results of the testing done using the adapter.

  6. Parameter testing for lattice filter based adaptive modal control systems

    NASA Technical Reports Server (NTRS)

    Sundararajan, N.; Williams, J. P.; Montgomery, R. C.

    1983-01-01

    For Large Space Structures (LSS), an adaptive control system is highly desirable. The present investigation is concerned with an 'indirect' adaptive control scheme wherein the system order, mode shapes, and modal amplitudes are estimated on-line using an identification scheme based on recursive, least-squares, lattice filters. Using the identified model parameters, a modal control law based on a pole-placement scheme with the objective of vibration suppression is employed. A method is presented for closed loop adaptive control of a flexible free-free beam. The adaptive control scheme consists of a two stage identification scheme working in series and a modal pole placement control scheme. The main conclusion from the current study is that the identified parameters cannot be directly used for controller design purposes.

  7. Course of COPD assessment test (CAT) and clinical COPD questionnaire (CCQ) scores during recovery from exacerbations of chronic obstructive pulmonary disease

    PubMed Central

    2013-01-01

    Introduction COPD exacerbations have a negative impact on lung function, decrease quality of life (QoL) and increase the risk of death. The objective of this study was to assess the course of health status after an outpatient or inpatient exacerbation in patients with COPD. Methods This is an epidemiological, prospective, multicentre study that was conducted in 79 hospitals and primary care centres in Spain. Four hundred seventy-six COPD patients completed COPD assessment test (CAT) and Clinical COPD Questionnaire (CCQ) questionnaires during the 24 hours after presenting at hospital or primary care centres with symptoms of an exacerbation, and also at weeks 4–6. The scores from the CAT and CCQ were evaluated and compared at baseline and after recovery from the exacerbation. Results A total of 164 outpatients (33.7%) and 322 inpatients (66.3%) were included in the study. The majority were men (88.2%), the mean age was 69.4 years (SD = 9.5) and the mean FEV1 (%) was 47.7% (17.4%). During the exacerbation, patients presented high scores in the CAT: [mean: 22.0 (SD = 7.0)] and the CCQ: [mean: 4.4 (SD = 1.2)]. After recovery there was a significant reduction in the scores of both questionnaires [CAT: mean: -9.9 (SD = 5.1) and CCQ: mean: -3.1 (SD = 1.1)]. Both questionnaires showed a strong correlation during and after the exacerbation and the best predictor of the magnitude of improvement in the scores was the severity of each score at onset. Conclusions Due to their good correlation, CAT and CCQ can be useful tools to measure health status during an exacerbation and to evaluate recovery. However, new studies are necessary in order to identify which factors are influencing the course of the recovery of health status after a COPD exacerbation. PMID:23987232

  8. Isolation and characterization of a catalase gene "HuCAT3" from pitaya (Hylocereus undatus) and its expression under abiotic stress.

    PubMed

    Nie, Qiong; Gao, Guo-Li; Fan, Qing-jie; Qiao, Guang; Wen, Xiao-Peng; Liu, Tao; Peng, Zhi-Jun; Cai, Yong-Qiang

    2015-05-25

    Abiotic stresses usually cause H2O2 accumulation, with harmful effects, in plants. Catalase may play a key protective role in plant cells by detoxifying this excess H2O2. Pitaya (Hylocereus undatus) shows broad ecological adaptation due to its high tolerance to abiotic stresses, e.g. drought, heat and poor soil. However, involvement of the pitaya catalase gene (HuCAT) in tolerance to abiotic stresses is unknown. In the present study, a full-length HuCAT3 cDNA (1870 bp) was isolated from pitaya based on our previous microarray data and RACE method. The cDNA sequence and deduced amino acid sequence shared 73-77% and 75-80% identity with other plant catalases, respectively. HuCAT3 contains conserved catalase family domain and catalytic sites. Pairwise comparison and phylogenetic analysis indicated that HuCAT3 is most similar to Eriobotrya japonica CAT, followed by Dimocarpus longan CAT and Nicotiana tabacum CAT1. Expression profile analysis demonstrated that HuCAT3 is mainly expressed in green cotyledons and mature stems, and was regulated by H2O2, drought, cold and salt stress, whereas, its expression patterns and maximum expression levels varied with stress types. HuCAT activity increased as exposure to the tested stresses, and the fluctuation of HuCAT activity was consistent with HuCAT3 mRNA abundance (except for 0.5 days upon drought stress). HuCAT3 mRNA elevations and HuCAT activities changes under cold stress were also in conformity with the cold tolerances among the four genotypes. The obtained results confirmed a major role of HuCAT3 in abiotic stress response of pitaya. This may prove useful in understanding pitaya's high tolerance to abiotic stresses at molecular level.

  9. Adaptive resolution simulation of liquid para-hydrogen: testing the robustness of the quantum-classical adaptive coupling.

    PubMed

    Poma, A B; Delle Site, L

    2011-06-14

    Adaptive resolution simulations for classical systems are currently made within a reasonably consistent theoretical framework. Recently we have extended this approach to the quantum-classical coupling by mapping the quantum nature of an atom onto a classical polymer ring representation within the path integral approach [Poma & Delle Site, Phys. Rev. Lett., 2010, 104, 250201]. In this way the process of interfacing adaptively a quantum representation to a classical one corresponds to the problem of interfacing two regions with a different number of effective "classical" degrees of freedom; thus the classical formulation of the adaptive algorithm applies straightforwardly to the quantum-classical problem. In this work we show the robustness of such an approach for a liquid of para-hydrogen at low temperature. This system represents a highly challenging conceptual and technical test for the adaptive approach due to the extreme thermodynamical conditions where quantum effects play a central role.

  10. A Model for Optimal Constrained Adaptive Testing. Law School Admission Council Computerized Testing Report. LSAC Research Report Series.

    ERIC Educational Resources Information Center

    van der Linden, Wim J.; Reese, Lynda M.

    A model for constrained computerized adaptive testing is proposed in which the information on the test at the ability estimate is maximized subject to a large variety of possible constraints on the contents of the test. At each item-selection step, a full test is first assembled to have maximum information at the current ability estimate fixing…

  11. Optimal Stratification of Item Pools in a-Stratified Computerized Adaptive Testing.

    ERIC Educational Resources Information Center

    Chang, Hua-Hua; van der Linden, Wim J.

    2003-01-01

    Developed a method based on 0-1 linear programming to stratify an item pool optimally for use in alpha-stratified adaptive testing. Applied the method to a previous item pool from the computerized adaptive test of the Graduate Record Examinations. Results show the new method performs well in practical situations. (SLD)

  12. A Mixture Rasch Model-Based Computerized Adaptive Test for Latent Class Identification

    ERIC Educational Resources Information Center

    Jiao, Hong; Macready, George; Liu, Junhui; Cho, Youngmi

    2012-01-01

    This study explored a computerized adaptive test delivery algorithm for latent class identification based on the mixture Rasch model. Four item selection methods based on the Kullback-Leibler (KL) information were proposed and compared with the reversed and the adaptive KL information under simulated testing conditions. When item separation was…

  13. Contractile properties of extraocular muscle in Siamese cat.

    PubMed

    Lennerstrand, G

    1979-01-01

    Siamese cats are albinos with poor visual resolution and severely impaired binocular vision. Eey muscle phyiology was studied in Siamese cats as a part of a more extensive project on eye muscle properties in cats with deficient binocular vision. Isometric contractions of the inferior oblique muscle were recorded in response to single and repetitive muscle nerve stimulation. Speed of contraction, measured as twitch contraction time, fusion frequency and rate of tetanic tension rise, was lower in Siamese than in normal cats. Eye muscles of Siamese cats fatiqued more easily to continuous activation than normal cat eye mucle. These functional changes have also been found in cats with binocular defects from monocular lid suture, but were much more marked in Siamese cats. It is suggested that the eye muscle changes represent muscular adaptations to genetically caused impairments of binocular vision and visual resolution in Siamese cats.

  14. Cat scratch disease

    MedlinePlus

    ... t scratch and bite. Don't allow a cat to lick your skin, eyes, mouth, or open wounds or scratches. Use flea control measures to lower the risk your cat develops the disease. Don't touch feral cats. ...

  15. A Durbin-Watson serial correlation test for ARX processes via excited adaptive tracking

    NASA Astrophysics Data System (ADS)

    Bercu, Bernard; Portier, Bruno; Vazquez, Victor

    2015-12-01

    We propose a new statistical test for the residual autocorrelation in ARX adaptive tracking. The introduction of a persistent excitation in the adaptive tracking control allows us to build a bilateral statistical test based on the well-known Durbin-Watson statistic. We establish the almost sure convergence and the asymptotic normality for the Durbin-Watson statistic leading to a powerful serial correlation test. Numerical experiments illustrate the good performances of our statistical test procedure.

  16. A Testlet Assembly Design for Adaptive Multistage Tests

    ERIC Educational Resources Information Center

    Luecht, Richard; Brumfield, Terry; Breithaupt, Krista

    2006-01-01

    This article describes multistage tests and some practical test development considerations related to the design and implementation of a multistage test, using the Uniform CPA (certified public accountant) Examination as a case study. The article further discusses the use of automated test assembly procedures in an operational context to produce…

  17. Multidimensional Computerized Adaptive Scholastic Aptitude Test Program Used for Grade 9 Students under Different Reviewing Test Conditions

    ERIC Educational Resources Information Center

    Khunkrai, Naruemon; Sawangboon, Tatsirin; Ketchatturat, Jatuphum

    2015-01-01

    The aim of this research is to study the accurate prediction of comparing test information and evaluation result by multidimensional computerized adaptive scholastic aptitude test program used for grade 9 students under different reviewing test conditions. Grade 9 students of the Secondary Educational Service Area Office in the North-east of…

  18. Cat scratch disease.

    PubMed

    Bozhkov, V; Madjov, R; Plachkov, I; Arnaudov, P; Chernopolsky, P; Krasnaliev, I

    2014-01-01

    Approximately 24,000 people are infected with cat scratch disease (CSD) every year. CSD is caused by the bacteria Bartonella henselae, a gram-negative bacteria most often transmitted to humans through a bite or scratch from an infected cat or kitten. Although CSD is often a benign and self-limiting condition, it can affect any major organ system in the body, manifesting in different ways and sometimes leading to lifelong sequelae. It is a disease that is often overlooked in primary care because of the wide range of symptom presentation and relative rarity of serious complications. It is important for health care providers to recognize patients at risk for CSD, know what laboratory testing and treatments are available, and be aware of complications that may arise from this disease in the future.

  19. Computerized Adaptive Spanish Placement Test. Final Performance Report.

    ERIC Educational Resources Information Center

    Larson, Jerry W.

    A study at Brigham Young University (Utah) investigated the feasibility of computer-assisted language placement testing in higher education. Benefits and problems of this approach for test administration, individualization of item selection, and recordkeeping were examined. Four steps were followed in production of a test for Spanish placement:…

  20. Using Out-of-Level Items in Computerized Adaptive Testing

    ERIC Educational Resources Information Center

    Wei, Hua; Lin, Jie

    2015-01-01

    Out-of-level testing refers to the practice of assessing a student with a test that is intended for students at a higher or lower grade level. Although the appropriateness of out-of-level testing for accountability purposes has been questioned by educators and policymakers, incorporating out-of-level items in formative assessments for accurate…

  1. A Comparison of Item-Selection Methods for Adaptive Tests with Content Constraints

    ERIC Educational Resources Information Center

    van der Linden, Wim J.

    2005-01-01

    In test assembly, a fundamental difference exists between algorithms that select a test sequentially or simultaneously. Sequential assembly allows us to optimize an objective function at the examinee's ability estimate, such as the test information function in computerized adaptive testing. But it leads to the non-trivial problem of how to realize…

  2. Comparison of polymerase chain reaction tests for diagnosis of feline herpesvirus, Chlamydophila felis, and Mycoplasma spp. infection in cats with ocular disease in Canada.

    PubMed

    Sandmeyer, Lynne S; Waldner, Cheryl L; Bauer, Bianca S; Wen, Xin; Bienzle, Dorothee

    2010-06-01

    This study assessed the value of polymerase chain reaction (PCR) for making a diagnosis of feline herpesvirus (FHV-1) infection, and for differentiating this from Chlamydophila felis and Mycoplasma spp. infection in a clinical setting in Canada. We compared the frequency of positive FHV-1 PCR test results from 48 clinical cases of ocular disease in cats suspected to be due to FHV-1 between 1 research and 2 commercial laboratories in Canada. We also compared PCR results for Chlamydophila felis and Mycoplasma spp. between the 2 commercial laboratories. The prevalence of FHV-1 infection in the cats ranged from 4% to 21%. The prevalence of Chlamydophila felis was 2% and 17% and the prevalence of Mycoplasma spp. was 11% and 27%. Agreement between FHV-1 culture and PCR results at the research laboratory was substantial (kappa = 0.76). There was slight agreement (kappa < 0.20) between the 3 laboratories for FHV-1 PCR and between the 2 commercial laboratories for both Chlamydophila felis (kappa = 0.2) and Mycoplasma spp. (kappa = 0.07) PCR.

  3. Transmission of feline immunodeficiency virus (FIV) among cohabiting cats in two cat rescue shelters.

    PubMed

    Litster, Annette L

    2014-08-01

    Conflicting accounts have been published in the veterinary literature regarding transmission of feline immunodeficiency virus (FIV) between cohabiting cats in mixed households, and the mechanics of possible casual transmission, if it occurs, are poorly understood. Similarly, there are conflicting reports of vertical transmission of FIV. The aim of the present study was to document the FIV serological status of cats taken into two rescue shelters. At rescue shelter 1 (Rescue 1), cats cohabited in a multi-cat household of FIV-negative and naturally-infected, FIV-positive cats. A study was performed that combined a retrospective review of records of FIV serological status at intake (Test 1) and prospective FIV serological testing (Tests 2 and 3). Retrospective records were analyzed at rescue shelter 2 (Rescue 2), where FIV-positive queens with litters of nursing kittens were taken into the shelter, before being rehomed. FIV serology was performed on all kittens after weaning. Initial test results (Test 1) for 138 cohabiting cats from Rescue 1 showed that there were 130 FIV-negative cats and eight FIV-positive cats (six male neutered and two female spayed). A second test (Test 2), performed in 45 of the FIV-negative and five of the FIV-positive cats at median 28 months after Test 1 (range, 1 month to 8.8 years) showed that results were unchanged. Similarly, a third test (Test 3), performed in four of the original FeLV-negative cats and one remaining FIV-positive cat at median 38 months after Test 1 (range, 4 months to 4 years), also showed that results were unchanged. These results show a lack of evidence of FIV transmission, despite years of exposure to naturally-infected, FIV-positive cats in a mixed household. At Rescue 2, records were available from five FIV-positive queens with 19 kittens. All 19 kittens tested FIV-negative, suggesting that vertical transmission had not occurred.

  4. Qualitative Examination of Children's Naming Skills through Test Adaptations.

    ERIC Educational Resources Information Center

    Fried-Oken, Melanie

    1987-01-01

    The Double Administration Naming Technique assists clinicians in obtaining qualitative information about a client's visual confrontation naming skills through administration of a standard naming test; readministration of the same test; identification of single and double errors; cuing for double naming errors; and qualitative analysis of naming…

  5. L(sub 1) Adaptive Control Design for NASA AirSTAR Flight Test Vehicle

    NASA Technical Reports Server (NTRS)

    Gregory, Irene M.; Cao, Chengyu; Hovakimyan, Naira; Zou, Xiaotian

    2009-01-01

    In this paper we present a new L(sub 1) adaptive control architecture that directly compensates for matched as well as unmatched system uncertainty. To evaluate the L(sub 1) adaptive controller, we take advantage of the flexible research environment with rapid prototyping and testing of control laws in the Airborne Subscale Transport Aircraft Research system at the NASA Langley Research Center. We apply the L(sub 1) adaptive control laws to the subscale turbine powered Generic Transport Model. The presented results are from a full nonlinear simulation of the Generic Transport Model and some preliminary pilot evaluations of the L(sub 1) adaptive control law.

  6. Adaptive antenna arrays for satellite communications: Design and testing

    NASA Technical Reports Server (NTRS)

    Gupta, I. J.; Swarner, W. G.; Walton, E. K.

    1985-01-01

    When two separate antennas are used with each feedback loop to decorrelate noise, the antennas should be located such that the phase of the interfering signal in the two antennas is the same while the noise in them is uncorrelated. Thus, the antenna patterns and spatial distribution of the auxiliary antennas are quite important and should be carefully selected. The selection and spatial distribution of auxiliary elements is discussed when the main antenna is a center fed reflector antenna. It is shown that offset feeds of the reflector antenna can be used as auxiliary elements of an adaptive array to suppress weak interfering signals. An experimental system is designed to verify the theoretical analysis. The details of the experimental systems are presented.

  7. Some Tests For Adaptative Observations In Atmospheric Chemistry

    NASA Astrophysics Data System (ADS)

    Quélo, D.; Michelangeli, P.-A.; Sportisse, B.

    Air pollution forecast requires the coupling of models with data through data assimi- lation. A key question is related to the choice of observations (apart from technical require- ments). One wants to choose in a judicious way the species to observe, in which loca- tions and at which moments. The appropriate strategies are related to the techniques of "targeting" and "adaptative observations". We will investigate these techniques on a simplified model. The first part reports the influence of the slow-fast behaviour of atmospheric chem- istry. The second part presents the use of singular vectors and second-order adjoint techniques in order to determine the "optimal" choice of observations. This project is led in the framework of the INRIA Cooperative Research Action CO- MODE (COupling MOdels and Data in Environment).

  8. Adaptation.

    PubMed

    Broom, Donald M

    2006-01-01

    The term adaptation is used in biology in three different ways. It may refer to changes which occur at the cell and organ level, or at the individual level, or at the level of gene action and evolutionary processes. Adaptation by cells, especially nerve cells helps in: communication within the body, the distinguishing of stimuli, the avoidance of overload and the conservation of energy. The time course and complexity of these mechanisms varies. Adaptive characters of organisms, including adaptive behaviours, increase fitness so this adaptation is evolutionary. The major part of this paper concerns adaptation by individuals and its relationships to welfare. In complex animals, feed forward control is widely used. Individuals predict problems and adapt by acting before the environmental effect is substantial. Much of adaptation involves brain control and animals have a set of needs, located in the brain and acting largely via motivational mechanisms, to regulate life. Needs may be for resources but are also for actions and stimuli which are part of the mechanism which has evolved to obtain the resources. Hence pigs do not just need food but need to be able to carry out actions like rooting in earth or manipulating materials which are part of foraging behaviour. The welfare of an individual is its state as regards its attempts to cope with its environment. This state includes various adaptive mechanisms including feelings and those which cope with disease. The part of welfare which is concerned with coping with pathology is health. Disease, which implies some significant effect of pathology, always results in poor welfare. Welfare varies over a range from very good, when adaptation is effective and there are feelings of pleasure or contentment, to very poor. A key point concerning the concept of individual adaptation in relation to welfare is that welfare may be good or poor while adaptation is occurring. Some adaptation is very easy and energetically cheap and

  9. The Childhood Autism Spectrum Test (CAST): Spanish adaptation and validation.

    PubMed

    Morales-Hidalgo, Paula; Roigé-Castellví, Joana; Vigil-Colet, Andreu; Canals Sans, Josefa

    2017-04-06

    The Childhood Autism Spectrum Test (CAST; Scott et al. Autism 2002; 6:9-31) has proved to be a good test for screening autism spectrum disorders (ASD) and social communication problems. This study provides evidence on the statistical properties of the CAST, specifically its validity, factorial structure and discriminative capacity as an ASD screening test, in a Spanish sample of 4-12 year-old children from community and clinical settings. The study concludes that the test was valid and reliable for ASD screening in Spanish clinical and community populations and allowed us to create a new abbreviated version. Autism Res 2017. © 2017 International Society for Autism Research, Wiley Periodicals, Inc.

  10. Test techniques: A survey paper on cryogenic tunnels, adaptive wall test sections, and magnetic suspension and balance systems

    NASA Technical Reports Server (NTRS)

    Kilgore, Robert A.; Dress, David A.; Wolf, Stephen W. D.; Britcher, Colin P.

    1989-01-01

    The ability to get good experimental data in wind tunnels is often compromised by things seemingly beyond our control. Inadequate Reynolds number, wall interference, and support interference are three of the major problems in wind tunnel testing. Techniques for solving these problems are available. Cryogenic wind tunnels solve the problem of low Reynolds number. Adaptive wall test sections can go a long way toward eliminating wall interference. A magnetic suspension and balance system (MSBS) completely eliminates support interference. Cryogenic tunnels, adaptive wall test sections, and MSBS are surveyed. A brief historical overview is given and the present state of development and application in each area is described.

  11. Accuracy and Precision of the Pediatric Evaluation of Disability Inventory Computer-Adaptive Tests (PEDI-CAT)

    ERIC Educational Resources Information Center

    Haley, Stephen M.; Coster, Wendy J.; Dumas, Helene M.; Fragala-Pinkham, Maria A.; Kramer, Jessica; Ni, Pengsheng; Tian, Feng; Kao, Ying-Chia; Moed, Rich; Ludlow, Larry H.

    2011-01-01

    Aim: The aims of the study were to: (1) build new item banks for a revised version of the Pediatric Evaluation of Disability Inventory (PEDI) with four content domains: daily activities, mobility, social/cognitive, and responsibility; and (2) use post-hoc simulations based on the combined normative and disability calibration samples to assess the…

  12. Four cats with fungal rhinitis.

    PubMed

    Whitney, Beth L; Broussard, John; Stefanacci, Joseph D

    2005-02-01

    Fungal rhinitis is uncommon in the cat and cases of nasal aspergillosis-penicilliosis have been rarely reported. Signs of fungal rhinitis include epistaxis, sneezing, mucopurulent nasal discharge and exophthalmos. Brachycephalic feline breeds seem to be at increased risk for development of nasal aspergillosis-penicilliosis. Computed tomography (CT) imaging and rhinoscopy are useful in assessing the extent of the disease and in obtaining diagnostic samples. Fungal culture may lead to false negative or positive results and must be used in conjunction with other diagnostic tests. Serological testing was not useful in two cats tested. The cats in this study were treated with oral itraconazole therapy. When itraconazole therapy was discontinued prematurely, clinical signs recurred. Hepatotoxicosis is a possible sequel to itraconazole therapy.

  13. Increasing Testing Efficiency through the Development of an IT-Based Adaptive Testing Tool for Competency Measurement

    ERIC Educational Resources Information Center

    Kleinhans, Janne; Schumann, Matthias

    2015-01-01

    Purpose: This paper investigates the potential of computerized adaptive testing for CMs to reduce test time. In the context of education and training, competency measurement (CM) is a central challenge in competency management. For complex CMs, a compromise must be addressed between the time available and the quality of the measurements.…

  14. Computer Adaptive Language Tests (CALT) Offer a Great Potential for Functional Testing. Yet Why Don't They?

    ERIC Educational Resources Information Center

    Meunier, Lydie E.

    1994-01-01

    Computer adaptive language testing (CALT) offers a variety of advantages; however, since CALT cannot test the multidimensional nature of language, it does not assess communicative/functional language. This article proposes to replace multiple choice and cloze formats and to apply CALT to live-action simulations. (18 references) (LB)

  15. A-Stratified Computerized Adaptive Testing with Unequal Item Exposure across Strata.

    ERIC Educational Resources Information Center

    Deng, Hui; Chang, Hua-Hua

    The purpose of this study was to compare a proposed revised a-stratified, or alpha-stratified, USTR method of test item selection with the original alpha-stratified multistage computerized adaptive testing approach (STR) and the use of maximum Fisher information (FSH) with respect to test efficiency and item pool usage using simulated computerized…

  16. Self Adapted Testing as Formative Assessment: Effects of Feedback and Scoring on Engagement and Performance

    ERIC Educational Resources Information Center

    Arieli-Attali, Meirav

    2016-01-01

    This dissertation investigated the feasibility of self-adapted testing (SAT) as a formative assessment tool with the focus on learning. Under two different orientation goals--to excel on a test (performance goal) or to learn from the test (learning goal)--I examined the effect of different scoring rules provided as interactive feedback, on test…

  17. Adaptation of a Vocabulary Test from British Sign Language to American Sign Language

    ERIC Educational Resources Information Center

    Mann, Wolfgang; Roy, Penny; Morgan, Gary

    2016-01-01

    This study describes the adaptation process of a vocabulary knowledge test for British Sign Language (BSL) into American Sign Language (ASL) and presents results from the first round of pilot testing with 20 deaf native ASL signers. The web-based test assesses the strength of deaf children's vocabulary knowledge by means of different mappings of…

  18. Computer-controlled noise adaption for acoustical test facilities

    NASA Astrophysics Data System (ADS)

    Wedig, W. V.; Ams, A.

    1990-09-01

    For acoustical noise tests of elastic structures, statistically representative signals generated from white noise by means of spectrum shapers and band pass filters are needed. Subsequently, these signals are amplified and transformed into physical test noise by acoustical sirens. A mathematical model of the entire system based on measurements of frequency transfer functions in order to predict an optimal amplitude modulation of the spectrum shaper is presented. The prediction is performed by means of a nonlinear optimization procedure which iterates the tuning parameters of the shaper with respect to the stored frequency data of the entire system.

  19. The full spectrum of climate change adaptation: testing an analytical framework in Tyrolean mountain agriculture (Austria).

    PubMed

    Grüneis, Heidelinde; Penker, Marianne; Höferl, Karl-Michael

    2016-01-01

    Our scientific view on climate change adaptation (CCA) is unsatisfying in many ways: It is often dominated by a modernistic perspective of planned pro-active adaptation, with a selective focus on measures directly responding to climate change impacts and thus it is far from real-life conditions of those who are actually affected by climate change. Farmers have to simultaneously adapt to multiple changes. Therefore, also empirical climate change adaptation research needs a more integrative perspective on real-life climate change adaptations. This also has to consider "hidden" adaptations, which are not explicitly and directly motivated by CCA but actually contribute to the sector's adaptability to climate change. The aim of the present study is to develop and test an analytic framework that contributes to a broader understanding of CCA and to bridge the gap between scientific expertise and practical action. The framework distinguishes three types of CCA according to their climate related motivations: explicit adaptations, multi-purpose adaptations, and hidden adaptations. Although agriculture is among the sectors that are most affected by climate change, results from the case study of Tyrolean mountain agriculture show that climate change is ranked behind other more pressing "real-life-challenges" such as changing agricultural policies or market conditions. We identified numerous hidden adaptations which make a valuable contribution when dealing with climate change impacts. We conclude that these hidden adaptations have not only to be considered to get an integrative und more realistic view on CCA; they also provide a great opportunity for linking adaptation strategies to farmers' realities.

  20. Designing P-Optimal Item Pools in Computerized Adaptive Tests with Polytomous Items

    ERIC Educational Resources Information Center

    Zhou, Xuechun

    2012-01-01

    Current CAT applications consist of predominantly dichotomous items, and CATs with polytomously scored items are limited. To ascertain the best approach to polytomous CAT, a significant amount of research has been conducted on item selection, ability estimation, and impact of termination rules based on polytomous IRT models. Few studies…

  1. Investigating Item Exposure Control Methods in Computerized Adaptive Testing

    ERIC Educational Resources Information Center

    Ozturk, Nagihan Boztunc; Dogan, Nuri

    2015-01-01

    This study aims to investigate the effects of item exposure control methods on measurement precision and on test security under various item selection methods and item pool characteristics. In this study, the Randomesque (with item group sizes of 5 and 10), Sympson-Hetter, and Fade-Away methods were used as item exposure control methods. Moreover,…

  2. Testing Adaptive Toolbox Models: A Bayesian Hierarchical Approach

    ERIC Educational Resources Information Center

    Scheibehenne, Benjamin; Rieskamp, Jorg; Wagenmakers, Eric-Jan

    2013-01-01

    Many theories of human cognition postulate that people are equipped with a repertoire of strategies to solve the tasks they face. This theoretical framework of a cognitive toolbox provides a plausible account of intra- and interindividual differences in human behavior. Unfortunately, it is often unclear how to rigorously test the toolbox…

  3. Traveling with Cognitive Tests: Testing the Validity of a KABC-II Adaptation in India

    ERIC Educational Resources Information Center

    Malda, Maike; van de Vijver, Fons J. R.; Srinivasan, Krishnamachari; Transler, Catherine; Sukumar, Prathima

    2010-01-01

    The authors evaluated the adequacy of an extensive adaptation of the American Kaufman Assessment Battery for Children, second edition (KABC-II), for 6- to 10-year-old Kannada-speaking children of low socioeconomic status in Bangalore, South India. The adapted KABC-II was administered to 598 children. Subtests showed high reliabilities, the…

  4. A Comparative Study of Online Pretest Item Calibration/Scaling Methods in CAT. ACT Research Report Series.

    ERIC Educational Resources Information Center

    Ban, Jae-Chun; Hanson, Bradley A.; Wang, Tianyou; Yi, Qing; Harris, Deborah J.

    The purpose of this study was to compare and evaluate five online pretest item calibration/scaling methods in computerized adaptive testing (CAT): (1) the marginal maximum likelihood estimate with one-EM cycle (OEM); (2) the marginal maximum likelihood estimate with multiple EM cycles (MEM); (3) Stocking's Method A (M. Stocking, 1988); (4)…

  5. Sample Size Reassessment and Hypothesis Testing in Adaptive Survival Trials

    PubMed Central

    Magirr, Dominic; Jaki, Thomas; Koenig, Franz; Posch, Martin

    2016-01-01

    Mid-study design modifications are becoming increasingly accepted in confirmatory clinical trials, so long as appropriate methods are applied such that error rates are controlled. It is therefore unfortunate that the important case of time-to-event endpoints is not easily handled by the standard theory. We analyze current methods that allow design modifications to be based on the full interim data, i.e., not only the observed event times but also secondary endpoint and safety data from patients who are yet to have an event. We show that the final test statistic may ignore a substantial subset of the observed event times. An alternative test incorporating all event times is found, where a conservative assumption must be made in order to guarantee type I error control. We examine the power of this approach using the example of a clinical trial comparing two cancer therapies. PMID:26863139

  6. Flight Test of an L(sub 1) Adaptive Controller on the NASA AirSTAR Flight Test Vehicle

    NASA Technical Reports Server (NTRS)

    Gregory, Irene M.; Xargay, Enric; Cao, Chengyu; Hovakimyan, Naira

    2010-01-01

    This paper presents results of a flight test of the L-1 adaptive control architecture designed to directly compensate for significant uncertain cross-coupling in nonlinear systems. The flight test was conducted on the subscale turbine powered Generic Transport Model that is an integral part of the Airborne Subscale Transport Aircraft Research system at the NASA Langley Research Center. The results presented are for piloted tasks performed during the flight test.

  7. Dirofilaria immitis in cats: diagnosis and management.

    PubMed

    Nelson, C Thomas

    2008-07-01

    Imaging and laboratory studies can help with the diagnosis of heartworm disease in cats, but no test is definitive. Furthermore, even when the diagnosis can be reliably established, therapy directed at the heartworms does little to help the cat. Rather, management is directed at alleviating clinical signs, with an emphasis on prevention for all.

  8. Adapting tests of sign language assessment for other sign languages--a review of linguistic, cultural, and psychometric problems.

    PubMed

    Haug, Tobias; Mann, Wolfgang

    2008-01-01

    Given the current lack of appropriate assessment tools for measuring deaf children's sign language skills, many test developers have used existing tests of other sign languages as templates to measure the sign language used by deaf people in their country. This article discusses factors that may influence the adaptation of assessment tests from one natural sign language to another. Two tests which have been adapted for several other sign languages are focused upon: the Test for American Sign Language and the British Sign Language Receptive Skills Test. A brief description is given of each test as well as insights from ongoing adaptations of these tests for other sign languages. The problems reported in these adaptations were found to be grounded in linguistic and cultural differences, which need to be considered for future test adaptations. Other reported shortcomings of test adaptation are related to the question of how well psychometric measures transfer from one instrument to another.

  9. Adaptive Stress Testing of Airborne Collision Avoidance Systems

    NASA Technical Reports Server (NTRS)

    Lee, Ritchie; Kochenderfer, Mykel J.; Mengshoel, Ole J.; Brat, Guillaume P.; Owen, Michael P.

    2015-01-01

    This paper presents a scalable method to efficiently search for the most likely state trajectory leading to an event given only a simulator of a system. Our approach uses a reinforcement learning formulation and solves it using Monte Carlo Tree Search (MCTS). The approach places very few requirements on the underlying system, requiring only that the simulator provide some basic controls, the ability to evaluate certain conditions, and a mechanism to control the stochasticity in the system. Access to the system state is not required, allowing the method to support systems with hidden state. The method is applied to stress test a prototype aircraft collision avoidance system to identify trajectories that are likely to lead to near mid-air collisions. We present results for both single and multi-threat encounters and discuss their relevance. Compared with direct Monte Carlo search, this MCTS method performs significantly better both in finding events and in maximizing their likelihood.

  10. Tuna fish diet influences cat behavior. [Elevated levels of selenium and mercury in commercial tuna fish cat food

    SciTech Connect

    Houpt, K.A.; Essick, L.A.; Shaw, E.B.; Alo, D.K.; Gilmartin, J.E.; Gutenmann, W.H.; Littman, C.B.; Lisk, D.J.

    1988-01-01

    When observed in their home cages, cats fed commercial tuna fish cat food were less active, vocalized less, and spent more time on the floor and more time eating than cats fed commercial beef cat food. There were no differences in response to human handling between the two groups. There were no differences in learning ability on a two-choice point maze or in reversal learning in the same maze between beef- and tuna-fed cats. The behavior of the groups differed in a 15-min open field test only in the number of toys contacted. Cats fed the tuna had elevated tissue levels of mercury and selenium.

  11. Adaptive interpretation of gas well deliverability tests with generating data of the IPR curve

    NASA Astrophysics Data System (ADS)

    Sergeev, V. L.; Phuong, Nguyen T. H.; Krainov, A. I.

    2017-01-01

    The paper considers topical issues of improving accuracy of estimated parameters given by data obtained from gas well deliverability tests, decreasing test time, and reducing gas emissions into the atmosphere. The aim of the research is to develop the method of adaptive interpretation of gas well deliverability tests with a resulting IPR curve and using a technique of generating data, which allows taking into account additional a priori information, improving accuracy of determining formation pressure and flow coefficients, reducing test time. The present research is based on the previous theoretical and practical findings in the spheres of gas well deliverability tests, systems analysis, system identification, function optimization and linear algebra. To test the method, the authors used the field data of deliverability tests of two wells, run in the Urengoy gas and condensate field, Tyumen Oblast. The authors suggest the method of adaptive interpretation of gas well deliverability tests with the resulting IPR curve and the possibility of generating data of bottomhole pressure and a flow rate at different test stages. The suggested method allows defining the estimates of the formation pressure and flow coefficients, optimal in terms of preassigned measures of quality, and setting the adequate number of test stages in the course of well testing. The case study of IPR curve data processing has indicated that adaptive interpretation provides more accurate estimates on the formation pressure and flow coefficients, as well as reduces the number of test stages.

  12. Effect of single-cat versus multi-cat home history on perceived behavioral stress in domestic cats (Felis silvestrus catus) in an animal shelter.

    PubMed

    Broadley, Heidi M; McCobb, Emily C; Slater, Margaret R

    2014-02-01

    This study investigates the effect of living with other cats in a prior home on stress levels of cats recently surrendered to an animal shelter. A total of 63 cats was evaluated using a Cat-Stress-Score and an approach test. Cats were categorized in terms of previous home history with or without other cats. No significant difference was found in stress scores between cats from single-cat households and those from multiple-cat households, although single cats that had been in the shelter less than 4 days demonstrated higher stress levels. No significant difference was found between the two groups in terms of approach results. Results of this study suggest that, in traditional individual cage settings, cats that are not accustomed to living with other cats may experience more stress in the initial few days of attempting to adjust to shelter existence. Through the use of such assessments, shelter personnel may develop an increased awareness to the needs of these cats and attempt to provide measures to improve their well-being within the shelter environment.

  13. I've Fallen and I Can't Get up: Can High-Ability Students Recover from Early Mistakes in CAT?

    ERIC Educational Resources Information Center

    Rulison, Kelly L.; Loken, Eric

    2009-01-01

    A difficult result to interpret in Computerized Adaptive Tests (CATs) occurs when an ability estimate initially drops and then ascends continuously until the test ends, suggesting that the true ability may be higher than implied by the final estimate. This study explains why this asymmetry occurs and shows that early mistakes by high-ability…

  14. Multidimensional Adaptive Testing in Educational and Psychological Measurement: Current State and Future Challenges

    ERIC Educational Resources Information Center

    Frey, Andreas; Seitz, Nicki-Nils

    2009-01-01

    The paper gives an overview of multidimensional adaptive testing (MAT) and evaluates its applicability in educational and psychological testing. The approach of Segall (1996) is described as a general framework for MAT. The main advantage of MAT is its capability to increase measurement efficiency. In simulation studies conceptualizing situations…

  15. An Enhanced Approach to Combine Item Response Theory with Cognitive Diagnosis in Adaptive Testing

    ERIC Educational Resources Information Center

    Wang, Chun; Zheng, Chanjin; Chang, Hua-Hua

    2014-01-01

    Computerized adaptive testing offers the possibility of gaining information on both the overall ability and cognitive profile in a single assessment administration. Some algorithms aiming for these dual purposes have been proposed, including the shadow test approach, the dual information method (DIM), and the constraint weighted method. The…

  16. Proceedings of the 1979 Computerized Adaptive Testing Conference (Wayzata, Minnesota, June 27-30, 1979).

    ERIC Educational Resources Information Center

    Weiss, David J., Ed.

    This report is the Proceedings of the third conference of its type. Included are 23 of the 25 papers presented at the conference, discussion of these papers by invited discussants, and symposium papers by a group of leaders in adaptive testing and latent trait test theory research and applications. The papers are organized into the following…

  17. Predictive Validity of Conventional and Adaptive Tests in an Air Force Training Environment. Interim Report.

    ERIC Educational Resources Information Center

    Sympson, James B.; And Others

    Conventional Armed Services Vocational Aptitude Battery-7 (ASVAB) Arithmetic Reasoning and Word Knowledge tests, were compared with computer-administered adaptive tests as predictors of performance in an Air Force Jet Engine Mechanic training course (n=495). Results supported earlier research in showing somewhat longer examinee response times for…

  18. Flight Test of Composite Model Reference Adaptive Control (CMRAC) Augmentation Using NASA AirSTAR Infrastructure

    NASA Technical Reports Server (NTRS)

    Gregory, Irene M.; Gadient, ROss; Lavretsky, Eugene

    2011-01-01

    This paper presents flight test results of a robust linear baseline controller with and without composite adaptive control augmentation. The flight testing was conducted using the NASA Generic Transport Model as part of the Airborne Subscale Transport Aircraft Research system at NASA Langley Research Center.

  19. Cat Scratch Disease

    MedlinePlus

    Cat scratch disease (CSD) is an illness caused by the bacterium Bartonella henselae. Almost half of all cats carry the infection ... symptoms of CSD, call your doctor. Centers for Disease Control and Prevention

  20. Cat-Scratch Disease

    MedlinePlus

    ... Patients Infants and Young Children Publications & Materials Announcements Cat-Scratch Disease Recommend on Facebook Tweet Share Compartir ( ... play and learn how to attack prey. How cats and people become infected Kitten playing with a ...

  1. Adapt

    NASA Astrophysics Data System (ADS)

    Bargatze, L. F.

    2015-12-01

    Active Data Archive Product Tracking (ADAPT) is a collection of software routines that permits one to generate XML metadata files to describe and register data products in support of the NASA Heliophysics Virtual Observatory VxO effort. ADAPT is also a philosophy. The ADAPT concept is to use any and all available metadata associated with scientific data to produce XML metadata descriptions in a consistent, uniform, and organized fashion to provide blanket access to the full complement of data stored on a targeted data server. In this poster, we present an application of ADAPT to describe all of the data products that are stored by using the Common Data File (CDF) format served out by the CDAWEB and SPDF data servers hosted at the NASA Goddard Space Flight Center. These data servers are the primary repositories for NASA Heliophysics data. For this purpose, the ADAPT routines have been used to generate data resource descriptions by using an XML schema named Space Physics Archive, Search, and Extract (SPASE). SPASE is the designated standard for documenting Heliophysics data products, as adopted by the Heliophysics Data and Model Consortium. The set of SPASE XML resource descriptions produced by ADAPT includes high-level descriptions of numerical data products, display data products, or catalogs and also includes low-level "Granule" descriptions. A SPASE Granule is effectively a universal access metadata resource; a Granule associates an individual data file (e.g. a CDF file) with a "parent" high-level data resource description, assigns a resource identifier to the file, and lists the corresponding assess URL(s). The CDAWEB and SPDF file systems were queried to provide the input required by the ADAPT software to create an initial set of SPASE metadata resource descriptions. Then, the CDAWEB and SPDF data repositories were queried subsequently on a nightly basis and the CDF file lists were checked for any changes such as the occurrence of new, modified, or deleted

  2. Quantitative resolution of spectroscopic systems using computer-assisted target factor analysis (CAT).

    PubMed

    Meinrath, G; Lis, S

    2001-01-02

    Factor analysis (FA) is widely applicable in analytical chemistry. For suitable data structures, the generality of the approach is a strong point of FA. Using target testing procedures, a wealth of specific informations on the components in a chemical system can be extracted without stating a specific model. Target testing, however, is time-consuming and often heuristic. In the following, application of a computer-assisted target factor analysis (CAT) algorithm is described. CAT estimates a rotation matrix that transforms abstract factors into physically meaningful informations by using general constraints, i.e. non-negativity of absorptions and/or concentrations. Thus, the rotation step in factor analysis is automated and allows application of target factor analysis to situations where none or only very limited information on the real factors and their respective contributions is available. Thus, a target testing procedure of guessing physically meaningful factors and iteratively adapting these factors is performed automatically. Nevertheless, CAT is not a black box procedure. The relative importance of different optimization constraints is balanced interactively. CAT can be applied to all situations where factor analysis can be used. CAT is demonstrated using UV-Vis absorption spectra of a Nd(III) polyoxometalate cryptate system and the system U(VI)-CO2-H2O as examples.

  3. Testing the role of luminance edges in White's illusion with contour adaptation.

    PubMed

    Betz, Torsten; Shapley, Robert; Wichmann, Felix A; Maertens, Marianne

    2015-08-01

    White's illusion is the perceptual effect that two equiluminant gray patches superimposed on a black-and-white square-wave grating appear different in lightness: A test patch placed on a dark stripe of the grating looks lighter than one placed on a light stripe. Although the effect does not depend on the aspect ratio of the test patches, and thus on the amount of border that is shared with either the dark or the light stripe, the context of each patch must, in a yet to be specified way, influence their lightness. We employed a contour adaptation paradigm (Anstis, 2013) to test the contribution of each of the test patches' edges to the perceived lightness of the test patches. We found that adapting to the edges that are oriented parallel to the grating slightly increased the lightness illusion, whereas adapting to the orthogonal edges abolished, or for some observers even reversed, the lightness illusion. We implemented a temporal adaptation mechanism in three spatial filtering models of lightness perception, and show that the models cannot account for the observed adaptation effects. We conclude that White's illusion is largely determined by edge contrast across the edge orthogonal to the grating, whereas the parallel edge has little or no influence. We suggest mechanisms that could explain this asymmetry.

  4. Exploring adaptations to the modified shuttle walking test

    PubMed Central

    Woolf-May, Kate; Meadows, Steve

    2013-01-01

    Objective The 10 m modified shuttle walking test (MSWT) is recommended to determine the functional capacity in older individuals and for patients entering cardiac rehabilitation. Participants are required to negotiate around cones set 1 m from the end markers. However, consistent comments indicate that for some individuals manoeuvring around the cones can be quite difficult. Therefore, the objective of this study was to explore differences within and between non-cardiac and postmyocardial infarction (MI) males during MSWT with and without the cones. Design Comparative study. Participants 20 post-MI (64.8±6.6, range 51–74 years) and 20 non-cardiac male controls (64.1±5.7, range 52–74 years) participated. Methods Participants performed MSWT with and without cones. Throughout, the participants expired air, and the heart rate (bpm) (HR) and ratings of perceived exertion (RPE) were measured. Participant protocol preference was recorded verbatim. Results One-way analysis of variance found no significant difference in VO2 peak (cones 20.4±5.1 vs no-cones 21.9±4.8 ml/kg/min, p=0.197) or distance ambulated (cones 631.8±132.9 m vs no-cones 662.4±164.1 m, p=0.371) between protocols or groups. Analysis comparing lines of regression showed a significant trajectory difference in VO2 (ml/kg/min) (p<0.01) between protocols with higher HR (p<0.01) and respiratory exchange ratio (RER, p<0.001) values during cones. RPEs were higher for post-MIs versus controls during both protocols (p<0.05). Post-MIs taking β-blockers produce significantly lower HR values. The χ2 analysis found no significant difference in protocol preference (no-cones: all n=25, 63%; post-MIs n=13, 65%; and controls n=12, 60%). Conclusions Post-MIs found both protocols subjectively harder than controls with no significant difference in the VO2 peak. However, both groups worked at a lesser percentage of their anaerobic threshold during no-cones protocol as indicated by lower RER values

  5. Cat-Scratch Disease

    MedlinePlus

    ... have diabetes or those who have acquired immunodeficiency syndrome (AIDS).Cat-scratch disease is also called cat-scratch fever. ... You can also get the bacteria in your eyes if you pet a cat that has the bacteria on its fur and ...

  6. CATS Featured Articles

    Atmospheric Science Data Center

    2017-01-31

      CATS Featured Articles       A Slice of Cirrus: Image of ... just hours before by the Cloud-Aerosol Transport System (CATS) onboard the International Space Station. Nighttime View of Raung Volcanic Plume : Natural Hazards  - The CATS instrument slices through darkness to reveal the vertical structure of a ...

  7. Seroprevalence of Toxoplasma gondii in cats from Colombo, Sri Lanka

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cats are essential in the life cycle of Toxoplasma gondii because they are the only hosts that can excrete the environmentally-resistant oocysts in nature. Nothing is known of the prevalence of Toxoplasma gondii in cats from Sri Lanka. Serum samples from 86 cats from Colombo, Sri Lanka were tested f...

  8. Wall interference tests of a CAST 10-2/DOA 2 airfoil in an adaptive-wall test section

    NASA Technical Reports Server (NTRS)

    Mineck, Raymond E.

    1987-01-01

    A wind-tunnel investigation of a CAST 10-2/DOA 2 airfoil model has been conducted in the adaptive-wall test section of the Langley 0.3-Meter Transonic Cryogenic Tunnel (TCT) and in the National Aeronautical Establishment High Reynolds Number Two-Dimensional Test Facility. The primary goal of the tests was to assess two different wall-interference correction techniques: adaptive test-section walls and classical analytical corrections. Tests were conducted over a Mach number range from 0.3 to 0.8 and over a chord Reynolds number range from 6 million to 70 million. The airfoil aerodynamic characteristics from the tests in the 0.3-m TCT have been corrected for wall interference by the movement of the adaptive walls. No additional corrections for any residual interference have been applied to the data, to allow comparison with the classically corrected data from the same model in the conventional National Aeronautical Establishment facility. The data are presented graphically in this report as integrated force-and-moment coefficients and chordwise pressure distributions.

  9. Flicker adaptation or superimposition raises the apparent spatial frequency of coarse test gratings.

    PubMed

    Kaneko, Sae; Giaschi, Deborah; Anstis, Stuart

    2015-03-01

    Independent channels respond to both the spatial and temporal characteristics of visual stimuli. Gratings <3 cycles per degree (cpd) are sensed by transient channels that prefer intermittent stimulation, while gratings >3 cpd are sensed by sustained channels that prefer steady stimulation. From this we predict that adaptation to a spatially uniform flickering field will selectively adapt the transient channels and raise the apparent spatial frequency of coarse sinusoidal gratings. Observers adapted to a spatially uniform field whose upper or lower half was steady and whose other half was flickering. They then adjusted the spatial frequency of a stationary test (matching) grating on the previously unmodulated half field until it matched the apparent spatial frequency of a grating falling on the previously flickering half field. The adapting field flickered at 8 Hz and the spatial frequency of the gratings was varied in octave steps from 0.25 to 16 cpd. As predicted, adapting to flicker raised the apparent spatial frequency of the test gratings. The aftereffect reached a peak of 11% between 0.5 and 1 cpd and disappeared above 4 cpd. We also observed that superimposed 10 Hz luminance flicker raised the apparent spatial frequency of 0.5 cpd test gratings. The effect was not seen with slower flicker or finer test gratings. Altogether, our study suggests that apparent spatial frequency is determined by the balance between transient and sustained channels and that an imbalance between the channels caused by flicker can alter spatial frequency perception.

  10. LUNAR MODULE TEST ARTICLE [LTA] [2R] IS MOVED FOR MATING TO LUNAR MODULE ADAPTER

    NASA Technical Reports Server (NTRS)

    1967-01-01

    The Lunar Module Test Article [LTA] 2R, for the second Saturn V mission, is being moved from the low bay of the Manned Spacecraft Operations Building for mating with the spacecraft Lunar Module Adapter. The second Saturn V [502], except for a different lunar return trajectory, will be a repeat of the Apollo 4 unmanned Earth orbital flight of a high apogee for systems testing using several propulsion system burns and a heat shield test at lunar re-entry speed.

  11. Proceedings of the Computerized Adaptive Testing Conference (1979) Held at Wayzata, Minnesota on 27-30 June 1979,

    DTIC Science & Technology

    1980-09-01

    Computerized Testing in the Federal Armed Forces ........................... Wolfgang Wildgrube 68 Session 3: Adaptive Mastery Testing 78 Some Decision...FORCES WOLFGANG WILDGRUBE GERMAN MINISTRY OF DEFENSE *A paper entitled "Test Construction Using Adaptive Administration Techniques," .1 by Wolfgang ...TESTING IN THE FEDERAL ARMED FORCES WOLFGANG WILDGRUBE GERMAN MINISTRY OF DEFENSE The Federal Armed Forces (FAF) consists of about 480,000 soldiers

  12. Reduction of feral cat (Felis catus Linnaeus 1758) colony size following hysterectomy of adult female cats.

    PubMed

    Mendes-de-Almeida, Flavya; Remy, Gabriella L; Gershony, Liza C; Rodrigues, Daniela P; Chame, Marcia; Labarthe, Norma V

    2011-06-01

    The size of urban cat colonies is limited only by the availability of food and shelter; therefore, their population growth challenges all known population control programs. To test a new population control method, a free-roaming feral cat colony at the Zoological Park in the city of Rio de Janeiro was studied, beginning in 2001. The novel method consisted of performing a hysterectomy on all captured female cats over 6 months of age. To estimate the size of the colony and compare population from year to year, a method of capture-mark-release-recapture was used. The aim was to capture as many individuals as possible, including cats of all ages and gender to estimate numbers of cats in all population categories. Results indicated that the feral cat population remained constant from 2001 to 2004. From 2004 to 2008, the hysterectomy program and population estimates were performed every other year (2006 and 2008). The population was estimated to be 40 cats in 2004, 26 in 2006, and 17 cats in 2008. Although pathogens tend to infect more individuals as the population grows older and maintains natural behavior, these results show that free-roaming feral cat colonies could have their population controlled by a biannual program that focuses on hysterectomy of sexually active female cats.

  13. Linguistic and cultural adaptation needs of Mexican American nursing students related to multiple-choice tests.

    PubMed

    Lujan, Josefina

    2008-07-01

    Hispanic nurses represent less than 2% of the current U.S. nursing workforce, despite that approximately 14% of the nation's population is Hispanic. There is an urgent need to correct the gross underrepresentation of Mexican Americans, the largest subgroup among Hispanics, in the U.S. nursing workforce to provide culturally concordant care. One solution is to increase the academic success of Mexican American nursing students with English as a second language through improved linguistic and cultural adaptation to multiple-choice tests. This article will discuss these students' linguistic and cultural adaptation needs related to multiple-choice tests and will also present several intervention strategies and a case study.

  14. Prevalence of infectious diseases in feral cats in Northern Florida.

    PubMed

    Luria, Brian J; Levy, Julie K; Lappin, Michael R; Breitschwerdt, Edward B; Legendre, Alfred M; Hernandez, Jorge A; Gorman, Shawn P; Lee, Irene T

    2004-10-01

    Objectives of this study were to determine prevalence of infection in feral cats in Northern Florida with a select group of infectious organisms and to determine risk factors for infection. Blood samples or sera from 553 cats were tested with a panel of antibody, antigen or PCR assays. Male cats were at higher risk for FIV, Mycoplasma haemofelis, and M. haemominutum. Infection with either FeLV or FIV was associated with increased risk for coinfection with the other retrovirus, M. haemofelis, or M. haemominutum. Bartonella henselae had the highest prevalence and was the only organism that did not have any associated risk for coinfection with other organisms. Feral cats in this study had similar or lower prevalence rates of infections than those published for pet cats in the United States. Thus, feral cats assessed in this study appear to be of no greater risk to human beings or other cats than pet cats.

  15. Feasibility and applicability of the paper and electronic COPD assessment test (CAT) and the clinical COPD questionnaire (CCQ) in primary care: a clinimetric study.

    PubMed

    Kocks, J W H; Blom, C M G; Kasteleyn, M J; Oosterom, W; Kollen, B J; Van der Molen, T; Chavannes, N H

    2017-03-28

    University Medical Center Groningen, administered both the COPD assessment test (CAT) and the clinical COPD questionnaire (CCQ) to 95 patients with the lung disease. These two tests are the most comprehensive assessments recommended by the global initiative for obstructive lung disease for guiding treatment decisions. The researchers found that both tests took approximately 95-100 s on average. Both tests were also equally easy to complete and provided similar types of information. Most patients said they had no preference for either one, and they filled out both electronic and paper versions of the questionnaires in much the same way. The authors conclude that both tests seem fine for routine use.

  16. Exocrine pancreatic insufficiency in the cat.

    PubMed

    Steiner, Jörg M

    2012-08-01

    Exocrine pancreatic insufficiency (EPI) is a syndrome caused by an insufficient amount of pancreatic digestive enzymes in the small intestine. Clinical signs most commonly reported in cats with EPI are weight loss, loose and voluminous stools, steatorrhea, polyphagia, and in some cases a greasy soiling of the hair coat in the perianal region. Serum feline trypsin-like immunoreactivity concentration is the diagnostic test of choice for the diagnosis of affected cats. Treatment of cats with EPI consists of enzyme supplementation with either a powdered pancreatic extract or raw pancreas. Most cats with EPI also have severely decreased serum cobalamin concentrations and may require lifelong parenteral cobalamin supplementation. Most cats respond well to therapy and can have a normal life expectancy and quality of life.

  17. Polycystic kidney disease in a Chartreux cat.

    PubMed

    Volta, Antonella; Manfredi, Sabrina; Gnudi, Giacomo; Gelati, Aldo; Bertoni, Giorgio

    2010-02-01

    Polycystic kidney disease (PKD) is one of the most common genetic diseases in cats. It has been widely described in Persians and Persian-related cats and sporadically in other breeds. The purpose of the present paper is to describe the first reported case of PKD in a 12-year-old female Chartreux cat. The cat was referred with polyuria and polydipsia and enlarged and irregular kidneys at palpation. Multiple renal cysts and a single liver cyst were identified by ultrasound and the inherited pattern was confirmed by genetic test (polymerase chain reaction/restriction fragment length polymorphism (PCR/RFLP) assay). Chartreux cats should be included in the screening programme of PKD, and PKD should be always considered as a possible cause of chronic renal failure in this breed.

  18. In Vivo Comparison of Two Human Norovirus Surrogates for Testing Ethanol-Based Handrubs: The Mouse Chasing the Cat!

    PubMed Central

    Sattar, Syed A.; Ali, Mohammad; Tetro, Jason A.

    2011-01-01

    Human noroviruses (HuNoV), a major cause of acute gastroenteritis worldwide, cannot be readily cultured in the lab. Therefore, a feline calicivirus (FCV) is often used as its surrogate to, among other things, test alcohol-based handrubs (ABHR). The more recent laboratory culture of a mouse norovirus (MNV) provides an alternative. While MNV is closer to HuNoV in several respects, to date, no comparative testing of FCV and MNV survival and inactivation on human hands has been performed. This study was designed to address the knowledge gap. The rates of loss in viability during drying on hands were −1.91 and −1.65% per minute for FCV and MNV, respectively. When the contaminated skin was exposed for 20 s to either a commercial ABHR with 62% (v/v) ethanol or to 75% (v/v) ethanol in water, FCV infectivity was reduced by <1 log10 while that of MNV by nearly 2.8 log10. Extending the contact time to 30 s reduced the FCV titer by almost 2 log10 by both test substances and that of MNV by >3.5 log10 by the commercial ABHR while 75% ethanol did not show any noticeable improvement in activity as compared to the 20 s contact. An 80% (v/v) aqueous solution of ethanol gave only a 1.75 log10 reduction in MNV activity after 20 s. The results show significant differences in the ethanol susceptibility of FCV and MNV in contact times relevant to field use of ABHR and also that 62% ethanol was a more effective virucide than either 75% or 80% ethanol. These findings indicate the need for a review of the continuing use of FCV as a surrogate for HuNoV. PMID:21390325

  19. Adaptive identification and interpretation of pressure transient tests of horizontal wells: challenges and perspectives

    NASA Astrophysics Data System (ADS)

    Sergeev, V. L.; Van Hoang, Dong

    2016-09-01

    The paper deals with a topical issue of defining oil reservoir properties during transient tests of horizontal wells equipped with information-measuring systems and reducing well downtime. The aim is to consider challenges and perspectives of developing models and algorithms for adaptive identification and interpretation of transient tests in horizontal wells with pressure buildup curve analysis. The models and algorithms should allow analyzing flow behavior, defining oil reservoir properties and determining well test completion time, as well as reducing well downtime. The present paper is based on the previous theoretical and practical findings in the spheres of transient well testing, systems analysis, system identification, function optimization and linear algebra. Field data and results of transient well tests with pressure buildup curve analysis have also been considered. The suggested models and algorithms for adaptive interpretation of transient tests conducted in horizontal wells with resulting pressure buildup curve make it possible to analyze flow behavior, as well as define the reservoir properties and determine well test completion time. The algorithms for adaptive interpretation are based on the integrated system of radial flow PBC models with time- dependent variables, account of additional a priori information and estimates of radial flow permeability. Optimization problems are solved with the case study of PBC interpretation for five horizontal wells of the Verkhnechonsk field.

  20. Malassezia spp. overgrowth in allergic cats.

    PubMed

    Ordeix, Laura; Galeotti, Franca; Scarampella, Fabia; Dedola, Carla; Bardagí, Mar; Romano, Erica; Fondati, Alessandra

    2007-10-01

    A series of 18 allergic cats with multifocal Malassezia spp. overgrowth is reported: atopic dermatitis was diagnosed in 16, an adverse food reaction in another and one was euthanized 2 months after diagnosis of Malassezia overgrowth. All the cats were otherwise healthy and those tested (16 out of 18) for feline leukaemia or feline immunodeficiency virus infections were all negative. At dermatological examination, multifocal alopecia, erythema, crusting and greasy adherent brownish scales were variably distributed on all cats. Cytological examination revealed Malassezia spp. overgrowth with/without bacterial infection in facial skin (n = 11), ventral neck (n = 6), abdomen (n = 6), ear canal (n = 4), chin (n = 2), ear pinnae (n = 2), interdigital (n = 1) and claw folds skin (n = 1). Moreover, in two cats Malassezia pachydermatis was isolated in fungal cultures from lesional skin. Azoles therapy alone was prescribed in seven, azoles and antibacterial therapy in eight and azoles with both antibacterial and anti-inflammatory therapy in three of the cats. After 3-4 weeks of treatment, substantial reduction of pruritus and skin lesions was observed in all 11 cats treated with a combined therapy and in five of seven treated solely with azoles. Malassezia spp. overgrowth may represent a secondary cutaneous problem in allergic cats particularly in those presented for dermatological examination displaying greasy adherent brownish scales. The favourable response to treatment with antifungal treatments alone suggests that, as in dogs, Malassezia spp. may be partly responsible for both pruritus and cutaneous lesions in allergic cats.

  1. Applications of Computerized Adaptive Testing. Proceedings of a Symposium presented at the Annual Convention of the Military Testing Association (18th, October 1976). Research Report 77-1.

    ERIC Educational Resources Information Center

    Weiss, David J., Ed.

    This symposium consists of five papers and presents some recent developments in adaptive testing which have applications to several military testing problems. The overview, by James R. McBride, defines adaptive testing and discusses some of its item selection and scoring strategies. Item response theory, or item characteristic curve theory, is…

  2. Fusimotor after-effects on responses of primary endings to test dynamic stimuli in cat muscle spindles.

    PubMed

    Emonet-Dénand, F; Hunt, C C; Laporte, Y

    1985-03-01

    Conditioning stimulation of individual dynamic fusimotor axons, either gamma or beta, leaves after-effects which enhance the responses of primary endings to test stimulation of the same axon applied during slow ramp stretch. These after-effects have a long duration, persisting well over 5 min, but are abolished by stretch of large amplitude. The dynamic after-effects also enhance frequencygrams elicited by low-frequency repetitive stimulation during slow ramp stretch, causing single stimuli to become much more effective. When several dynamic axons to the same spindle are isolated, conditioning stimulation of one leaves an after-effect to test stimulation of itself and of all other dynamic axons. When two dynamic axons are used for conditioning stimulation, facilitation or occlusion can be demonstrated in their interaction, indicating that they converge on the same intrafusal element. Dynamic after-effects persist during background static fusimotor activity of considerable amplitude, suggesting that static and dynamic actions are quite independent. Dynamic after-effects appear to result from residual changes in the bag fibre, probably from a persistent increase in the number of cross-bridges between thick and thin filaments. These after-effects produce a large increase in the response of primary endings to dynamic fusimotor activity and probably have an important functional role.

  3. Operational Characteristics of Adaptive Testing Procedures Using the Graded Response Model.

    ERIC Educational Resources Information Center

    Dodd, Barbara G.; And Others

    1989-01-01

    General guidelines are developed to assist practitioners in devising operational computerized adaptive testing systems based on the graded response model. The effects of the following major variables were examined: item pool size; stepsize used along the trait continuum until maximum likelihood estimation could be calculated; and stopping rule…

  4. Optimal Stratification of Item Pools in a-Stratified Computerized Adaptive Testing. Research Report.

    ERIC Educational Resources Information Center

    van der Linden, Wim J.

    A method based on 0-1 linear programming (LP) is presented to stratify an item pool optimally for use in "alpha"-stratified adaptive testing. Because the 0-1 LP model belongs to the subclass of models with a network-flow structure, efficient solutions are possible. The method is applied to a previous item pool from the computerized…

  5. Item Response Theory and Computerized Adaptive Testing Conference Proceedings (Wayzata, Minnesota, July 27-30, 1982).

    ERIC Educational Resources Information Center

    Weiss, David J., Ed.

    This report contains the Proceedings of the 1982 Item Response Theory and Computerized Adaptive Testing Conference. The papers and their discussions are organized into eight sessions: (1) "Developments in Latent Trait Theory," with papers by Fumiko Samejima and Michael V. Levine; (2) "Parameter Estimation," with papers by…

  6. A Revised Version of the Norwegian Adaptation of the Test Anxiety Inventory in a Heterogeneous Population

    ERIC Educational Resources Information Center

    Oktedalen, Tuva; Hagtvet, Knut A.

    2011-01-01

    Confirmatory factor analysis and Multiple Indicators, Multiple Causes (MIMIC) modeling were employed to investigate psychometric properties of a revised adaptation of the Norwegian version of the Test Anxiety Inventory (RTAIN) in a sample of 456 students. The study supported the Norwegian version as a useful inventory for measuring the components…

  7. Adapting the Bilingual Aphasia Test to Rarotongan (Cook Islands Maori): Linguistic and Clinical Considerations

    ERIC Educational Resources Information Center

    Amberber, Amanda Miller

    2011-01-01

    This article describes the adaptation of the Bilingual Aphasia Test (BAT) to the Rarotongan dialect of Cook Islands Maori, a Polynesian language spoken in the Cook Islands and expatriate communities. A brief linguistic sketch of Rarotongan is presented. As Rarotongan is characterised by a complex pronominal system, "a" versus "o" possession and…

  8. The Adaptation of Naval Enlistees Scoring in Mental Group 4 on the Armed Forces Qualification Test.

    ERIC Educational Resources Information Center

    Plag, John A.; And Others

    This report presents findings from a study evaluating differences in the adaptation of "average" and mentally marginal sailors during four years of military service. Sailors with Armed Forces Qualification Test (AFQT) scores of 50 are significantly superior to Category 4 enlistees on military performance measures which stress cognitive…

  9. A Monte Carlo Approach to the Design, Assembly, and Evaluation of Multistage Adaptive Tests

    ERIC Educational Resources Information Center

    Belov, Dmitry I.; Armstrong, Ronald D.

    2008-01-01

    This article presents an application of Monte Carlo methods for developing and assembling multistage adaptive tests (MSTs). A major advantage of the Monte Carlo assembly over other approaches (e.g., integer programming or enumerative heuristics) is that it provides a uniform sampling from all MSTs (or MST paths) available from a given item pool.…

  10. On the Impact of Adaptive Test Question Selection for Learning Efficiency

    ERIC Educational Resources Information Center

    Barla, Michal; Bielikova, Maria; Ezzeddinne, Anna Bou; Kramar, Tomas; Simko, Marian; Vozar, Oto

    2010-01-01

    In this paper we present a method for adaptive selection of test questions according to the individual needs of students within a web-based educational system. It functions as a combination of three particular methods. The first method is based on the course structure and focuses on the selection of the most appropriate topic for learning. The…

  11. Test Adaptation and Cross-Cultural Assessment From a Business Perspective: Issues and Recommendations

    ERIC Educational Resources Information Center

    Casillas, Alex; Robbins, Steven B.

    2005-01-01

    Test adaptation and cross-cultural assessment activities are skyrocketing as the demand for educational opportunities and personnel selection grow both within the United States and across the industrializing world. We chose a qualitative, case study approach to identify central themes encountered by ACT, a not-for-profit organization that has…

  12. Bayesian Item Selection Criteria for Adaptive Testing. Research Report 96-01.

    ERIC Educational Resources Information Center

    van der Linden, Wim J.

    R. J. Owen (1975) proposed an approximate empirical Bayes procedure for item selection in adaptive testing. The procedure replaces the true posterior by a normal approximation with closed-form expressions for its first two moments. This approximation was necessary to minimize the computational complexity involved in a fully Bayesian approach, but…

  13. Incorporation of Content Balancing Requirements in Stratification Designs for Computerized Adaptive Testing.

    ERIC Educational Resources Information Center

    Leung, Chi-Keung; Chang, Hua-Hua; Hau, Kit-Tai

    2003-01-01

    Studied three stratification designs for computerized adaptive testing in conjunction with three well-developed content balancing methods. Simulation study results show substantial differences in item overlap rate and pool utilization among different methods. Recommends an optimal combination of stratification design and content balancing method.…

  14. Taylor Approximations to Logistic IRT Models and Their Use in Adaptive Testing.

    ERIC Educational Resources Information Center

    Veerkamp, Wim J. J.

    2000-01-01

    Showed how Taylor approximation can be used to generate a linear approximation to a logistic item characteristic curve and a linear ability estimator. Demonstrated how, for a specific simulation, this could result in the special case of a Robbins-Monro item selection procedure for adaptive testing. (SLD)

  15. Restrictive Stochastic Item Selection Methods in Cognitive Diagnostic Computerized Adaptive Testing

    ERIC Educational Resources Information Center

    Wang, Chun; Chang, Hua-Hua; Huebner, Alan

    2011-01-01

    This paper proposes two new item selection methods for cognitive diagnostic computerized adaptive testing: the restrictive progressive method and the restrictive threshold method. They are built upon the posterior weighted Kullback-Leibler (KL) information index but include additional stochastic components either in the item selection index or in…

  16. Diagnostic Classification Models and Multidimensional Adaptive Testing: A Commentary on Rupp and Templin

    ERIC Educational Resources Information Center

    Frey, Andreas; Carstensen, Claus H.

    2009-01-01

    On a general level, the objective of diagnostic classifications models (DCMs) lies in a classification of individuals regarding multiple latent skills. In this article, the authors show that this objective can be achieved by multidimensional adaptive testing (MAT) as well. The authors discuss whether or not the restricted applicability of DCMs can…

  17. Psychometric Evaluation of the Italian Adaptation of the Test of Inferential and Creative Thinking

    ERIC Educational Resources Information Center

    Faraci, Palmira; Hell, Benedikt; Schuler, Heinz

    2016-01-01

    This article describes the psychometric properties of the Italian adaptation of the "Analyse des Schlussfolgernden und Kreativen Denkens" (ASK; Test of Inferential and Creative Thinking) for measuring inferential and creative thinking. The study aimed to (a) supply evidence for the factorial structure of the instrument, (b) describe its…

  18. An Adaptive Testing Strategy for Mastery Decisions. Research Report 79-5.

    ERIC Educational Resources Information Center

    Kingsbury, G. Gage; Weiss, David J.

    The theory and technology of item characteristic curve (ICC) response theory and adaptive testing were applied to judging individuals' competencies against a prespecified mastery level to determine whether each individual is a "master" or "nonmaster" of a specified content domain. Items from two conventionally administered mastery tests…

  19. A hierarchical Bayesian approach to adaptive vision testing: A case study with the contrast sensitivity function

    PubMed Central

    Gu, Hairong; Kim, Woojae; Hou, Fang; Lesmes, Luis Andres; Pitt, Mark A.; Lu, Zhong-Lin; Myung, Jay I.

    2016-01-01

    Measurement efficiency is of concern when a large number of observations are required to obtain reliable estimates for parametric models of vision. The standard entropy-based Bayesian adaptive testing procedures addressed the issue by selecting the most informative stimulus in sequential experimental trials. Noninformative, diffuse priors were commonly used in those tests. Hierarchical adaptive design optimization (HADO; Kim, Pitt, Lu, Steyvers, & Myung, 2014) further improves the efficiency of the standard Bayesian adaptive testing procedures by constructing an informative prior using data from observers who have already participated in the experiment. The present study represents an empirical validation of HADO in estimating the human contrast sensitivity function. The results show that HADO significantly improves the accuracy and precision of parameter estimates, and therefore requires many fewer observations to obtain reliable inference about contrast sensitivity, compared to the method of quick contrast sensitivity function (Lesmes, Lu, Baek, & Albright, 2010), which uses the standard Bayesian procedure. The improvement with HADO was maintained even when the prior was constructed from heterogeneous populations or a relatively small number of observers. These results of this case study support the conclusion that HADO can be used in Bayesian adaptive testing by replacing noninformative, diffuse priors with statistically justified informative priors without introducing unwanted bias. PMID:27105061

  20. Effect of Rasch Calibration on Ability and DIF Estimation in Computer-Adaptive Tests.

    ERIC Educational Resources Information Center

    Zwick, Rebecca; And Others

    1995-01-01

    In a simulation study of ability and estimation of differential item functioning (DIF) in computerized adaptive tests, Rasch-based DIF statistics were highly correlated with generating DIF, but DIF statistics tended to be slightly smaller than in the three-parameter logistic model analyses. (SLD)

  1. The Problem of Bias in Person Parameter Estimation in Adaptive Testing

    ERIC Educational Resources Information Center

    Doebler, Anna

    2012-01-01

    It is shown that deviations of estimated from true values of item difficulty parameters, caused for example by item calibration errors, the neglect of randomness of item difficulty parameters, testlet effects, or rule-based item generation, can lead to systematic bias in point estimation of person parameters in the context of adaptive testing.…

  2. SIMCA T 1.0: A SAS Computer Program for Simulating Computer Adaptive Testing

    ERIC Educational Resources Information Center

    Raiche, Gilles; Blais, Jean-Guy

    2006-01-01

    Monte Carlo methodologies are frequently applied to study the sampling distribution of the estimated proficiency level in adaptive testing. These methods eliminate real situational constraints. However, these Monte Carlo methodologies are not currently supported by the available software programs, and when these programs are available, their…

  3. Approaching Sign Language Test Construction: Adaptation of the German Sign Language Receptive Skills Test

    ERIC Educational Resources Information Center

    Haug, Tobias

    2011-01-01

    There is a current need for reliable and valid test instruments in different countries in order to monitor deaf children's sign language acquisition. However, very few tests are commercially available that offer strong evidence for their psychometric properties. A German Sign Language (DGS) test focusing on linguistic structures that are acquired…

  4. Kansas Adapted/Special Physical Education Test Manual. Health Related Fitness and Psychomotor Testing.

    ERIC Educational Resources Information Center

    Johnson, Robert E.; Lavay, Barry

    This manual was developed to address the need for health-related physical fitness testing of children with special needs. The first section defines the components of health-related physical fitness which consist of: (1)abdominal strength and endurance measured by a sit-up test; (2) flexibility, measured by a sit and reach test; (3) upper body…

  5. Confidence in Pass/Fail Decisions for Computer Adaptive and Paper and Pencil Examinations.

    ERIC Educational Resources Information Center

    Bergstrom, Betty A.; Lunz, Mary E.

    The level of confidence in pass/fail decisions obtained with computer adaptive tests (CATs) was compared to decisions based on paper-and-pencil tests. Subjects included 645 medical technology students from 238 educational programs across the country. The tests used in this study constituted part of the subjects' review for the certification…

  6. Adapting the Get Yourself Tested Campaign to Reach Black and Latino Sexual-Minority Youth

    PubMed Central

    Garbers, Samantha; Friedman, Allison; Martinez, Omar; Scheinmann, Roberta; Bermudez, Dayana; Silva, Manel; Silverman, Jen; Chiasson, Mary Ann

    2016-01-01

    Background Culturally appropriate efforts are needed to increase sexually transmitted disease (STD) testing and care among Black and Latino sexual-minority youth, who are at high risk for STDs. Get Yourself Tested, a national testing campaign, has demonstrated success among youth, but it has yet to be assessed for relevance or impact among this population. Method This effort included (1) formative and materials-testing research through focus groups; (2) adaptation of existing Get Yourself Tested campaign materials to be more inclusive of Black and Latino sexual-minority youth; (3) a 3-month campaign in four venues of New York City, promoting STD testing at events and through mobile testing and online and social media platforms; (4) process evaluation of outreach activities; and (5) an outcome evaluation of testing at select campaign venues, using a preexperimental design. Results During the 3-month campaign period, the number of STD tests conducted at select campaign venues increased from a comparable 3-month baseline period. Although testing uptake through mobile vans remained low in absolute numbers, the van drew a high-prevalence sample, with positivity rates of 26.9% for chlamydia and 11.5% for gonorrhea. This article documents the process and lessons learned from adapting and implementing a local campaign for Black and Latino sexual-minority youth. PMID:27225216

  7. International Space Station Environmental Control and Life Support System Acceptance Testing for the Pressurized Mating Adapters

    NASA Technical Reports Server (NTRS)

    Williams, David E.

    2008-01-01

    The International Space Station (ISS) Pressurized Mating Adapters (PMAs) Environmental Control and Life Support (ECLS) System is comprised of three subsystems: Atmosphere Control and Supply (ACS), Temperature and Humidity Control (THC), and Water Recovery and Management (WRM). PMAs 1 and 2 flew to ISS on Flight 2A and Pressurized Mating Adapter (PMA) 3 flew to ISS on Flight 3A. This paper provides a summary of the PMAs ECLS design and a detailed discussion of the ISS ECLS Acceptance Testing methodologies utilized for the PMAs.

  8. Computerised Axial Tomography (CAT)

    DTIC Science & Technology

    1990-06-01

    OF COMPUTERISED AXIAL TOMOGRAPHY Paragraph 1.1 ORIGIN, DEVELOPMENT AND MARKET OF CAT Paragraph 1.2 EQUIPMENT Chapter 2 OPERATIONAL PRINCIPLE OF A CT...DEVELOPMENT OF THE COMPUTERISED AXIAL TOMOGRAPHY 1.1 Origin, development and marketing of the CAT The origin of the CAT goes back to 1961 when...count on wide commercial possibilities, in the international market . In particular, EMI entered, very forcefully, the American market , always

  9. Detecting Local Item Dependence in Polytomous Adaptive Data

    ERIC Educational Resources Information Center

    Mislevy, Jessica L.; Rupp, Andre A.; Harring, Jeffrey R.

    2012-01-01

    A rapidly expanding arena for item response theory (IRT) is in attitudinal and health-outcomes survey applications, often with polytomous items. In particular, there is interest in computer adaptive testing (CAT). Meeting model assumptions is necessary to realize the benefits of IRT in this setting, however. Although initial investigations of…

  10. Feline Epitheliotropic Mastocytic Conjunctivitis in 15 Cats.

    PubMed

    Beckwith-Cohen, B; Dubielzig, R R; Maggs, D J; Teixeira, L B C

    2017-01-01

    Mast cell infiltration occurs in malignant, inflammatory (eg, allergic, infectious), and idiopathic disease processes in humans and animals. Here, we describe the clinical and histological features of a unique proliferative conjunctivitis occurring in 15 cats. Ocular specimens were examined histologically, and polymerase chain reaction (PCR) for feline herpesvirus 1 (FHV-1) was performed on ocular tissues obtained from 10 cats. Cats had a median age of 8 years (range: 7 months-17.5 years). The known median duration of ocular lesions prior to biopsy was 4 months (range: 1 week-3 years). Ocular disease was unilateral in 12 cats, and 9 cats had coexisting corneal disease. Clinically and histologically, proliferative or nodular conjunctival lesions were noted in 13 cats. The nictitating membrane was affected in 10 cats. Histologically, lesions were characterized by mixed inflammatory infiltrates with an abundance of Giemsa-positive and toluidine blue-positive intraepithelial and subepithelial mast cells, marked edema, and papillary epithelial hyperplasia. Feline herpesvirus 1 was demonstrated by PCR in 1 of 10 cats tested. Follow-up information was available for 14 cats: 8 had no recurrence during a median follow-up period of 17.5 months (range: 4.5-30 months), 2 underwent orbital exenteration, 3 had recurrence that was medically managed, and 1 cat had diffuse conjunctivitis at the time of biopsy and recurrence was deemed irrelevant. Various ocular medications were administered before and after surgical biopsy. This condition was designated as feline epitheliotropic mastocytic conjunctivitis, with intraepithelial mast cells being an essential feature and papillary epithelial proliferation being characteristic but not diagnostic alone. The condition appears to be uncommon and benign. Although the cause is unknown, an allergic component is possible.

  11. Hepatozoon species infection in domestic cats: a retrospective study.

    PubMed

    Baneth, G; Aroch, I; Tal, N; Harrus, S

    1998-10-01

    Hepatozoon sp. is a protozoan parasite of peripheral blood neutrophils in cats. Feline hepatozoonosis has been reported infrequently and little is known about the pathogenesis of this infection. In order to further clarify clinicopathological characteristics of hepatozoonosis in domestic cats, a retrospecitve study of hepatozoonosis in cats admitted during 1989-1995 to the Hebrew University School of Veterinary Medicine was conducted. The study population comprised all the cats whose medical records included a complete blood count with a microscopical examination of a blood smear during this 7-year period (n=1229). Hepatozoon gametocytes were identified in seven cats (0.57%) ranging from 1 to 6 years of age. Infected cats were mostly males (6/7) of mixed breed (5/7) with a variety of complaints and clinical signs. The clinicopathological findings included increased activities of serum lactate dehydrogenase (LDH) (5/6) and creatine kinase (CK) (5/6). The elevated enzymes detected in cats with hepatozoonosis are suggestive of muscular damage. Sixty-seven percent (4/6) of the cats with hepatozoonosis which were tested for a retroviral disease were found infected either in FIV or FELV. In addition, 2/7 cats were co-infected with Hemobartonella felis. In conclusion, parasitemia with Hepatozoon sp. is a rare finding in cats from Israel. The over-representation of cats with a retroviral disease among the cats with hepatozoonosis indicates a possible association between immunosupression and the development of Hepatozoon infection.

  12. High-Resolution Adaptive Optics Test-Bed for Vision Science

    SciTech Connect

    Wilks, S C; Thomspon, C A; Olivier, S S; Bauman, B J; Barnes, T; Werner, J S

    2001-09-27

    We discuss the design and implementation of a low-cost, high-resolution adaptive optics test-bed for vision research. It is well known that high-order aberrations in the human eye reduce optical resolution and limit visual acuity. However, the effects of aberration-free eyesight on vision are only now beginning to be studied using adaptive optics to sense and correct the aberrations in the eye. We are developing a high-resolution adaptive optics system for this purpose using a Hamamatsu Parallel Aligned Nematic Liquid Crystal Spatial Light Modulator. Phase-wrapping is used to extend the effective stroke of the device, and the wavefront sensing and wavefront correction are done at different wavelengths. Issues associated with these techniques will be discussed.

  13. [Assessment of cardiorespiratory fitness in preschool children: adaptation of the 20 metres shuttle run test].

    PubMed

    Cadenas-Sánchez, Cristina; Alcántara-Moral, Francisco; Sánchez-Delgado, Guillermo; Mora-González, José; Martínez-Téllez, Borja; Herrador-Colmenero, Manuel; Jiménez-Pavón, David; Femia, Pedro; Ruiz, Jonatan R; Ortega, Francisco B

    2014-12-01

    Cardiorespiratory fitness is a strong indicator of present and future health in children and adolescents, however it is unknown whether it is for pre-schoolers, from 3 to 5 years. In the present study, we described the adaptation of the original 20m shuttle run test, it feasibility and acceptance in children from 3 to 5 years and its maximality and reliability. A total of 130 students (4.91 ± 0.89 years; 77 boys) performed the test twice, two weeks apart. The test adaptation consisted mainly in reducing the initial speed of 8.5 km/h to 6.5 km/h. The test was feasible and was well accepted in both boys and girls and the three age groups, 3, 4 and 5 years. The maximum heart rate (MHR) achieved for the entire sample was 199.4 ± 12.5 beats/min, equivalent to 97% of the estimated theoretical MHR, and no significant differences by gender or age. Mean test-retest difference (systematic error) in the number of laps achieved was 2 laps, with no significant differences between sex or age. There was no evidence of heteroscedasticity. Our results suggest the test is maximum and reliable in this age group. Future longitudinal or intervention studies using this test should take into account that changes in the test performance of 2 laps may be due to the variability of the measure, while wider changes would be attributable to the intervention or changes associated with age.

  14. Ferrokinetic and erythrocyte survival studies in healthy and anemic cats

    SciTech Connect

    Madewell, B.R.; Holmes, P.H.; Onions, D.E.

    1983-03-01

    Erythrocyte survival and ferrokinetic studies were adapted to the cat. For 5 clinically healthy 4- to 9-month-old cats, mean /sup 51/Cr-labeled erythrocyte survival was 144 hours, and mean plasma /sup 59/Fe-labeled transferrin disappearance halftime was 51 minutes. Erythrocyte use of radioiron was rapid and efficient, with 50% to 80% of labeled iron incorporated into the erythron by 100 hours after injection into the cat. Six cats with feline leukemia virus infection were studied. For 2 cats with erythroid aplasia associated with C subgroup of feline leukemia virus, erythrocyte survival times were similar to those determined for the healthy cats, but plasma radioiron disappearance half time and erythrocyte use of radioiron were markedly diminished.

  15. Design and Preliminary Testing of the International Docking Adapter's Peripheral Docking Target

    NASA Technical Reports Server (NTRS)

    Foster, Christopher W.; Blaschak, Johnathan; Eldridge, Erin A.; Brazzel, Jack P.; Spehar, Peter T.

    2015-01-01

    The International Docking Adapter's Peripheral Docking Target (PDT) was designed to allow a docking spacecraft to judge its alignment relative to the docking system. The PDT was designed to be compatible with relative sensors using visible cameras, thermal imagers, or Light Detection and Ranging (LIDAR) technologies. The conceptual design team tested prototype designs and materials to determine the contrast requirements for the features. This paper will discuss the design of the PDT, the methodology and results of the tests, and the conclusions pertaining to PDT design that were drawn from testing.

  16. Capabilities of wind tunnels with two-adaptive walls to minimize boundary interference in 3-D model testing

    NASA Technical Reports Server (NTRS)

    Rebstock, Rainer; Lee, Edwin E., Jr.

    1989-01-01

    An initial wind tunnel test was made to validate a new wall adaptation method for 3-D models in test sections with two adaptive walls. First part of the adaptation strategy is an on-line assessment of wall interference at the model position. The wall induced blockage was very small at all test conditions. Lift interference occurred at higher angles of attack with the walls set aerodynamically straight. The adaptation of the top and bottom tunnel walls is aimed at achieving a correctable flow condition. The blockage was virtually zero throughout the wing planform after the wall adjustment. The lift curve measured with the walls adapted agreed very well with interference free data for Mach 0.7, regardless of the vertical position of the wing in the test section. The 2-D wall adaptation can significantly improve the correctability of 3-D model data. Nevertheless, residual spanwise variations of wall interference are inevitable.

  17. Clinical and Pathologic Evaluation of Chronic Bartonella henselae or Bartonella clarridgeiae Infection in Cats

    PubMed Central

    Kordick, Dorsey L.; Brown, Talmage T.; Shin, KwangOk; Breitschwerdt, Edward B.

    1999-01-01

    Human Bartonella infections result in diverse medical presentations, whereas many cats appear to tolerate chronic bacteremia without obvious clinical abnormalities. Eighteen specific-pathogen-free cats were inoculated with Bartonella henselae- and/or Bartonella clarridgeiae-infected cat blood and monitored for 454 days. Relapsing bacteremia did not correlate with changes in protein profiles or differences in antigenic protein recognition. Intradermal skin testing did not induce a delayed type hypersensitivity reaction to cat scratch disease skin test antigen. Thirteen cats were euthanatized at the end of the study. Despite persistent infection, clinical signs were minimal and gross necropsy results were unremarkable. Histopathology revealed peripheral lymph node hyperplasia (in all of the 13 cats), splenic follicular hyperplasia (in 9 cats), lymphocytic cholangitis/pericholangitis (in 9 cats), lymphocytic hepatitis (in 6 cats), lymphoplasmacytic myocarditis (in 8 cats), and interstitial lymphocytic nephritis (in 4 cats). Structures suggestive of Bartonella were visualized in some Warthin-Starry stained sections, and Bartonella DNA was amplified from the lymph node (from 6 of the 13 cats), liver (from 11 cats) heart (from 8 cats), kidney (from 9 cats), lung (from 2 cats), and brain (from 9 cats). This study indicates that B. henselae or B. clarridgeiae can induce chronic infection following blood transfusion in specific-pathogen-free cats and that Bartonella DNA can be detected in blood, brain, lymph node, myocardium, liver, and kidney tissues of both blood culture-positive cats and blood culture-negative cats. Detection of histologic changes in these cats supports a potential etiologic role for Bartonella species in several idiopathic disease processes in cats. PMID:10203518

  18. Estimation of the dietary nutrient profile of free-roaming feral cats: possible implications for nutrition of domestic cats.

    PubMed

    Plantinga, Esther A; Bosch, Guido; Hendriks, Wouter H

    2011-10-01

    Cats are strict carnivores and in the wild rely on a diet solely based on animal tissues to meet their specific and unique nutritional requirements. Although the feeding ecology of cats in the wild has been well documented in the literature, there is no information on the precise nutrient profile to which the cat's metabolism has adapted. The present study aimed to derive the dietary nutrient profile of free-living cats. Studies reporting the feeding habits of cats in the wild were reviewed and data on the nutrient composition of the consumed prey items obtained from the literature. Fifty-five studies reported feeding strategy data of cats in the wild. After specific exclusion criteria, twenty-seven studies were used to derive thirty individual dietary nutrient profiles. The results show that feral cats are obligatory carnivores, with their daily energy intake from crude protein being 52 %, from crude fat 46 % and from N-free extract only 2 %. Minerals and trace elements are consumed in relatively high concentrations compared with recommended allowances determined using empirical methods. The calculated nutrient profile may be considered the nutrient intake to which the cat's metabolic system has adapted. The present study provides insight into the nutritive, as well as possible non-nutritive aspects of a natural diet of whole prey for cats and provides novel ways to further improve feline diets to increase health and longevity.

  19. Sleep deprivation selectively disrupts top-down adaptation to cognitive conflict in the Stroop test.

    PubMed

    Gevers, Wim; Deliens, Gaetane; Hoffmann, Sophie; Notebaert, Wim; Peigneux, Philippe

    2015-12-01

    Sleep deprivation is known to exert detrimental effects on various cognitive domains, including attention, vigilance and working memory. Seemingly at odds with these findings, prior studies repeatedly failed to evidence an impact of prior sleep deprivation on cognitive interference in the Stroop test, a hallmark paradigm in the study of cognitive control abilities. The present study investigated further the effect of sleep deprivation on cognitive control using an adapted version of the Stroop test that allows to segregate top-down (attentional reconfiguration on incongruent items) and bottom-up (facilitated processing after repetitions in responses and/or features of stimuli) components of performance. Participants underwent a regular night of sleep or a night of total sleep deprivation before cognitive testing. Results disclosed that sleep deprivation selectively impairs top-down adaptation mechanisms: cognitive control no longer increased upon detection of response conflict at the preceding trial. In parallel, bottom-up abilities were found unaffected by sleep deprivation: beneficial effects of stimulus and response repetitions persisted. Changes in vigilance states due to sleep deprivation selectively impact on cognitive control in the Stroop test by affecting top-down, but not bottom-up, mechanisms that guide adaptive behaviours.

  20. Implementation of an Adaptive Controller System from Concept to Flight Test

    NASA Technical Reports Server (NTRS)

    Larson, Richard R.; Burken, John J.; Butler, Bradley S.; Yokum, Steve

    2009-01-01

    The National Aeronautics and Space Administration Dryden Flight Research Center (Edwards, California) is conducting ongoing flight research using adaptive controller algorithms. A highly modified McDonnell-Douglas NF-15B airplane called the F-15 Intelligent Flight Control System (IFCS) is used to test and develop these algorithms. Modifications to this airplane include adding canards and changing the flight control systems to interface a single-string research controller processor for neural network algorithms. Research goals include demonstration of revolutionary control approaches that can efficiently optimize aircraft performance in both normal and failure conditions and advancement of neural-network-based flight control technology for new aerospace system designs. This report presents an overview of the processes utilized to develop adaptive controller algorithms during a flight-test program, including a description of initial adaptive controller concepts and a discussion of modeling formulation and performance testing. Design finalization led to integration with the system interfaces, verification of the software, validation of the hardware to the requirements, design of failure detection, development of safety limiters to minimize the effect of erroneous neural network commands, and creation of flight test control room displays to maximize human situational awareness; these are also discussed.

  1. A Submaximal Running Test With Postexercise Cardiac Autonomic and Neuromuscular Function in Monitoring Endurance Training Adaptation.

    PubMed

    Vesterinen, Ville; Nummela, Ari; Laine, Tanja; Hynynen, Esa; Mikkola, Jussi; Häkkinen, Keijo

    2017-01-01

    Vesterinen, V, Nummela, A, Laine, T, Hynynen, E, Mikkola, J, and Häkkinen, K. A submaximal running test with postexercise cardiac autonomic and neuromuscular function in monitoring endurance training adaptation. J Strength Cond Res 31(1): 233-243, 2017-The aim of this study was to investigate whether a submaximal running test (SRT) with postexercise heart rate recovery (HRR), heart rate variability (HRV), and countermovement jump (CMJ) measurements could be used to monitor endurance training adaptation. Thirty-five endurance-trained men and women completed an 18-week endurance training. Maximal endurance performance and maximal oxygen uptake were measured every 8 weeks. In addition, SRTs with postexercise HRR, HRV, and CMJ measurements were carried out every 4 weeks. Submaximal running test consisted of two 6-minute stages at 70 and 80% of maximum heart rate (HRmax) and a 3-minute stage at 90% HRmax, followed by a 2-minute recovery stage for measuring postexercise HRR, HRV, and CMJ test. The highest responders according to the change of maximal endurance performance showed a significant improvement in running speeds during stages 2 and 3 in SRT, whereas no changes were observed in the lowest responders. The strongest correlation was found between the change of maximal endurance performance and running speed during stage 3, whereas no significant relationships were found between the change of maximal endurance performance and the changes of postexercise HRR, HRV, and CMJ. Running speed at 90% HRmax intensity was the most sensitive variable to monitor adaptation to endurance training. The present submaximal test showed potential to monitor endurance training adaptation. Furthermore, it may serve as a practical tool for athletes and coaches to evaluate weekly the effectiveness of training program without interfering in the normal training habits.

  2. Susceptibility of domestic cats to chronic wasting disease.

    PubMed

    Mathiason, Candace K; Nalls, Amy V; Seelig, Davis M; Kraft, Susan L; Carnes, Kevin; Anderson, Kelly R; Hayes-Klug, Jeanette; Hoover, Edward A

    2013-02-01

    Domestic and nondomestic cats have been shown to be susceptible to feline spongiform encephalopathy (FSE), almost certainly caused by consumption of bovine spongiform encephalopathy (BSE)-contaminated meat. Because domestic and free-ranging nondomestic felids scavenge cervid carcasses, including those in areas affected by chronic wasting disease (CWD), we evaluated the susceptibility of the domestic cat (Felis catus) to CWD infection experimentally. Cohorts of 5 cats each were inoculated intracerebrally (i.c.) or orally (p.o.) with CWD-infected deer brain. At 40 and 42 months postinoculation, two i.c.-inoculated cats developed signs consistent with prion disease, including a stilted gait, weight loss, anorexia, polydipsia, patterned motor behaviors, head and tail tremors, and ataxia, and the cats progressed to terminal disease within 5 months. Brains from these two cats were pooled and inoculated into cohorts of cats by the i.c., p.o., and intraperitoneal and subcutaneous (i.p./s.c.) routes. Upon subpassage, feline CWD was transmitted to all i.c.-inoculated cats with a decreased incubation period of 23 to 27 months. Feline-adapted CWD (Fel(CWD)) was demonstrated in the brains of all of the affected cats by Western blotting and immunohistochemical analysis. Magnetic resonance imaging revealed abnormalities in clinically ill cats, which included multifocal T2 fluid attenuated inversion recovery (FLAIR) signal hyperintensities, ventricular size increases, prominent sulci, and white matter tract cavitation. Currently, 3 of 4 i.p./s.c.- and 2 of 4 p.o. secondary passage-inoculated cats have developed abnormal behavior patterns consistent with the early stage of feline CWD. These results demonstrate that CWD can be transmitted and adapted to the domestic cat, thus raising the issue of potential cervid-to-feline transmission in nature.

  3. Eosinophilic leukaemia in a cat.

    PubMed

    Sharifi, Hassan; Nassiri, Seyed Mahdi; Esmaelli, Hossein; Khoshnegah, Javad

    2007-12-01

    A 14-year-old female domestic shorthair cat was presented to Tehran University Veterinary Teaching Hospital for a persistent fever, anorexia, intermittent vomiting, weight loss and weakness. The main clinical signs were pale mucous membranes, dehydration and splenomegaly. The complete blood count and serum biochemistry tests revealed non-regenerative anaemia, thrombocytopenia and increased alkaline phosphatase (ALP) activity. An enzyme-linked immunosorbent assay (ELISA) test for feline leukaemia virus was negative. Blood film and bone marrow examination revealed a large number of immature eosinophils with variable sizes and numbers of faintly azurophilic granules. Cytochemical staining of blood film demonstrated 70% positive cells for ALP activity. Four percent CD34 positive cells were detected by flow cytometry. As eosinophilic leukaemia is difficult to identify by light microscopy, well-defined diagnostic criteria and the use of flow cytometry and cytochemical staining can improve the ability to correctly diagnose this type of leukaemia in cats.

  4. Fairness in Computerized Testing: Detecting Item Bias Using CATSIB with Impact Present

    ERIC Educational Resources Information Center

    Chu, Man-Wai; Lai, Hollis

    2013-01-01

    In educational assessment, there is an increasing demand for tailoring assessments to individual examinees through computer adaptive tests (CAT). As such, it is particularly important to investigate the fairness of these adaptive testing processes, which require the investigation of differential item function (DIF) to yield information about item…

  5. That Fat Cat

    ERIC Educational Resources Information Center

    Lambert, Phyllis Gilchrist

    2012-01-01

    This activity began with a picture book, Nurit Karlin's "Fat Cat On a Mat" (HarperCollins; 1998). The author and her students started their project with a 5-inch circular template for the head of their cats. They reviewed shapes as they drew the head and then added the ears and nose, which were triangles. Details to the face were added when…

  6. Second order Horner's syndrome in a cat.

    PubMed

    De Risio, Luisa; Fraser McConnell, James

    2009-08-01

    This case report describes the clinical and magnetic resonance imaging (MRI) findings of a 3.5-year-old, male neutered, domestic shorthair cat with second order Horner's syndrome as the only clinical abnormality. The neuroanatomical pathway of the sympathetic innervation to the eye, differential diagnoses for Horner's syndrome in cats, and the interpretation of pharmacological testing are reviewed. The unusual MRI findings and the value of fat-suppressed MRI sequences are discussed.

  7. Adapting and Testing the COAMPS/COBEL Low Cloud Nowcasting System for Winter Conditions

    DTIC Science & Technology

    2001-09-30

    Adapting and Testing the COAMPS/ COBEL Low Cloud Nowcasting System for Winter Conditions Professor Peter Zwack, Earth and Atmospheric Sciences...514-987-7749 email: zwack.peter@uqam.ca Award Number: N00014-01-1-0377 http://people.sca.uqam.ca/~ cobel /COTE_EST/ http://people.sca.uqam.ca...tardif/ COBEL /cobel_enter.htm LONG-TERM GOALS An improved an automated, globally applicable, integrated ceiling forecast product in DAMPS that

  8. Aeroelastic Deformation: Adaptation of Wind Tunnel Measurement Concepts to Full-Scale Vehicle Flight Testing

    NASA Technical Reports Server (NTRS)

    Burner, Alpheus W.; Lokos, William A.; Barrows, Danny A.

    2005-01-01

    The adaptation of a proven wind tunnel test technique, known as Videogrammetry, to flight testing of full-scale vehicles is presented. A description is presented of the technique used at NASA's Dryden Flight Research Center for the measurement of the change in wing twist and deflection of an F/A-18 research aircraft as a function of both time and aerodynamic load. Requirements for in-flight measurements are compared and contrasted with those for wind tunnel testing. The methodology for the flight-testing technique and differences compared to wind tunnel testing are given. Measurement and operational comparisons to an older in-flight system known as the Flight Deflection Measurement System (FDMS) are presented.

  9. State of cat genomics.

    PubMed

    O'Brien, Stephen J; Johnson, Warren; Driscoll, Carlos; Pontius, Joan; Pecon-Slattery, Jill; Menotti-Raymond, Marilyn

    2008-06-01

    Our knowledge of cat family biology was recently expanded to include a genomics perspective with the completion of a draft whole genome sequence of an Abyssinian cat. The utility of the new genome information has been demonstrated by applications ranging from disease gene discovery and comparative genomics to species conservation. Patterns of genomic organization among cats and inbred domestic cat breeds have illuminated our view of domestication, revealing linkage disequilibrium tracks consequent of breed formation, defining chromosome exchanges that punctuated major lineages of mammals and suggesting ancestral continental migration events that led to 37 modern species of Felidae. We review these recent advances here. As the genome resources develop, the cat is poised to make a major contribution to many areas in genetics and biology.

  10. Some Useful Cost-Benefit Criteria for Evaluating Computer-Based Test Delivery Models and Systems

    ERIC Educational Resources Information Center

    Luecht, Richard M.

    2005-01-01

    Computer-based testing (CBT) is typically implemented using one of three general test delivery models: (1) multiple fixed testing (MFT); (2) computer-adaptive testing (CAT); or (3) multistage testing (MSTs). This article reviews some of the real cost drivers associated with CBT implementation--focusing on item production costs, the costs…

  11. Comparative study of aural microflora in healthy cats, allergic cats and cats with systemic disease.

    PubMed

    Pressanti, Charline; Drouet, Clémence; Cadiergues, Marie-Christine

    2014-12-01

    Twenty healthy cats (group 1) with clinically normal ears, 15 cats with systemic disease (group 2) and 15 allergic cats (group 3) were included in a prospective study. The experimental unit was the ear. A clinical score was established for each ear canal after otoscopic examination. Microbial population was assessed on cytological examination of smears performed with the cotton-tipped applicator smear technique. Fungal population was significantly more prominent in allergic cats (P <0.001) and in diseased cats compared with healthy cats (P <0.02). Bacterial population was significantly higher in allergic cats than in healthy cats (P <0.001) and cats suffering from systemic disease (P <0.001). Bacterial overgrowth was also higher in cats with systemic disease than healthy cats. In cats from group 2, only fungal overgrowth was associated with otitis severity. In group 3, only bacterial overgrowth was associated with otitis severity.

  12. The application of in vitro sperm competition test to evaluate the impact of ZP-derived peptides on fertilization capacity of cat sperm.

    PubMed

    Niu, Yuyu; Greube, Alexa; Ji, Weizhi; Jewgenow, Katarina

    2006-09-01

    The present study aimed to establish a sensitive in vitro assay to assess the binding capacity of cat spermatozoa. Cat oocytes and epididymal sperm cells were isolated from gonads and cultured for in vitro fertilization. Before fertilization, the sperm cells were incubated either in 10 microM green dye Fluo-3-AM or 10 microM orange dye CellTracker Orange CMTMR (Molecular Probes), respectively. After removing the dyes by washing, sperm cells stained with each dye were added to medium drops containing oocytes in various proportions and cultured for 16 h at 37 degrees C, 5% CO(2). The oocytes were examined using fluorescence microscopy. Sperm bound to oocytes, and stained with different colors, were counted. When fresh epididymal sperm were mixed in at a specific proportion, the number of sperm bound to the zona pellucida (ZP) of oocytes reflected the proportion of differently colored sperm in the medium. This indicated that neither dye influenced the binding capacity of cat sperm. Mixing fresh and cryopreserved sperm, however, resulted in a higher number of fresh sperm bound to the oocyte surface in comparison to frozen-thawed sperm. Also, the pre-incubation of cat sperm cells with ZP derived peptide reduced the sperm binding capacity by 40%. In conclusion, the presented sperm competition assay allows assessment of fertilizing capacity of cat spermatozoa in vitro when a mixture of two different populations is used. The applied supravital fluorescence dyes do not affect motility and binding capacity of sperm cells and were clearly distinguishable under fluorescence microscopy. We demonstrate that the assay can be used to study the impact of sperm treatment, such as cryopreservation or pre-incubation in bioactive peptides, on fertilizing capacity.

  13. Flight Test of L1 Adaptive Control Law: Offset Landings and Large Flight Envelope Modeling Work

    NASA Technical Reports Server (NTRS)

    Gregory, Irene M.; Xargay, Enric; Cao, Chengyu; Hovakimyan, Naira

    2011-01-01

    This paper presents new results of a flight test of the L1 adaptive control architecture designed to directly compensate for significant uncertain cross-coupling in nonlinear systems. The flight test was conducted on the subscale turbine powered Generic Transport Model that is an integral part of the Airborne Subscale Transport Aircraft Research system at the NASA Langley Research Center. The results presented include control law evaluation for piloted offset landing tasks as well as results in support of nonlinear aerodynamic modeling and real-time dynamic modeling of the departure-prone edges of the flight envelope.

  14. Immobility in the forced swim test is adaptive and does not reflect depression.

    PubMed

    Molendijk, Marc L; de Kloet, E Ronald

    2015-12-01

    The forced swim test is based on the progressive immobility a rodent displays when immersed in a beaker filled with water from where no escape is possible. While the test was originally designed to identify the antidepressant potential of drugs, over the past decade a rapidly growing number of publications (more than 2000) portray this immobility response anthropomorphically as a measure for depression and despair. This is incorrect. The response to the forced swim stressor should be considered for what it shows: a switch from active to passive behavior in the face of an acute stressor, aligned to cognitive functions underlying behavioral adaptation and survival.

  15. Serological survey of vector-borne zoonotic pathogens in pet cats and cats from animal shelters and feral colonies.

    PubMed

    Case, Joseph Brad; Chomel, Bruno; Nicholson, William; Foley, Janet E

    2006-04-01

    Although cats and their arthropod parasites can sometimes be important sources of zoonotic diseases in humans, the extent of exposure among various cat populations to many potential zoonotic agents remains incompletely described. In this study, 170 domestic cats living in private homes, feral cat colonies, and animal shelters from California and Wisconsin were evaluated by serology to determine the levels of exposure to a group of zoonotic vector-borne pathogens. Serological positive test results were observed in 17.2% of cats for Rickettsia rickettsii, 14.9% for R akari, 4.9% for R typhi, 11.1% for R felis, and 14.7% for Bartonella henselae. Although vector-borne disease exposure has been documented previously in cats, the evaluation of multiple pathogens and diverse cat populations simultaneously performed here contributes to our understanding of feline exposure to these zoonotic pathogens.

  16. Validation of a Computerized Adaptive Version of the Schedule for Nonadaptive and Adaptive Personality (SNAP)

    ERIC Educational Resources Information Center

    Simms, Leonard J.; Clark, Lee Anna

    2005-01-01

    This is a validation study of a computerized adaptive (CAT) version of the Schedule for Nonadaptive and Adaptive Personality (SNAP) conducted with 413 undergraduates who completed the SNAP twice, 1 week apart. Participants were assigned randomly to 1 of 4 retest groups: (a) paper-and-pencil (P&P) SNAP, (b) CAT, (c) P&P/CAT, and (d) CAT/P&P. With…

  17. Adaptive and Qualitative Changes in Encoding Strategy With Experience: Evidence From the Test-Expectancy Paradigm

    PubMed Central

    Finley, Jason R.; Benjamin, Aaron S.

    2012-01-01

    Three experiments demonstrated learners’ abilities to adaptively and qualitatively accommodate their encoding strategies to the demands of an upcoming test. Stimuli were word pairs. In Experiment 1, test expectancy was induced for either cued recall (of targets given cues) or free recall (of targets only) across 4 study–test cycles of the same test format, followed by a final critical cycle featuring either the expected or the unexpected test format. For final tests of both cued and free recall, participants who had expected that test format outperformed those who had not. This disordinal interaction, supported by recognition and self-report data, demonstrated not mere differences in effort based on anticipated test difficulty, but rather qualitative and appropriate differences in encoding strategies based on expected task demands. Participants also came to appropriately modulate metacognitive monitoring (Experiment 2) and study-time allocation (Experiment 3) across study–test cycles. Item and associative recognition performance, as well as self-report data, revealed shifts in encoding strategies across trials; these results were used to characterize and evaluate the different strategies that participants employed for cued versus free recall and to assess the optimality of participants’ metacognitive control of encoding strategies. Taken together, these data illustrate a sophisticated form of metacognitive control, in which learners qualitatively shift encoding strategies to match the demands of anticipated tests. PMID:22103783

  18. Adaptive and qualitative changes in encoding strategy with experience: evidence from the test-expectancy paradigm.

    PubMed

    Finley, Jason R; Benjamin, Aaron S

    2012-05-01

    Three experiments demonstrated learners' abilities to adaptively and qualitatively accommodate their encoding strategies to the demands of an upcoming test. Stimuli were word pairs. In Experiment 1, test expectancy was induced for either cued recall (of targets given cues) or free recall (of targets only) across 4 study-test cycles of the same test format, followed by a final critical cycle featuring either the expected or the unexpected test format. For final tests of both cued and free recall, participants who had expected that test format outperformed those who had not. This disordinal interaction, supported by recognition and self-report data, demonstrated not mere differences in effort based on anticipated test difficulty, but rather qualitative and appropriate differences in encoding strategies based on expected task demands. Participants also came to appropriately modulate metacognitive monitoring (Experiment 2) and study-time allocation (Experiment 3) across study-test cycles. Item and associative recognition performance, as well as self-report data, revealed shifts in encoding strategies across trials; these results were used to characterize and evaluate the different strategies that participants employed for cued versus free recall and to assess the optimality of participants' metacognitive control of encoding strategies. Taken together, these data illustrate a sophisticated form of metacognitive control, in which learners qualitatively shift encoding strategies to match the demands of anticipated tests.

  19. Exaptation in human evolution: how to test adaptive vs exaptive evolutionary hypotheses.

    PubMed

    Pievani, Telmo; Serrelli, Emanuele

    2011-01-01

    Palaeontologists, Stephen J. Gould and Elisabeth Vrba, introduced the term "ex-aptation" with the aim of improving and enlarging the scientific language available to researchers studying the evolution of any useful character, instead of calling it an "adaptation" by default, coming up with what Gould named an "extended taxonomy of fitness". With the extension to functional co-optations from non-adaptive structures ("spandrels"), the notion of exaptation expanded and revised the neo-Darwinian concept of "pre-adaptation" (which was misleading, for Gould and Vrba, suggesting foreordination). Exaptation is neither a "saltationist" nor an "anti-Darwinian" concept and, since 1982, has been adopted by many researchers in evolutionary and molecular biology, and particularly in human evolution. Exaptation has also been contested. Objections include the "non-operationality objection".We analyze the possible operationalization of this concept in two recent studies, and identify six directions of empirical research, which are necessary to test "adaptive vs. exaptive" evolutionary hypotheses. We then comment on a comprehensive survey of literature (available online), and on the basis of this we make a quantitative and qualitative evaluation of the adoption of the term among scientists who study human evolution. We discuss the epistemic conditions that may have influenced the adoption and appropriate use of exaptation, and comment on the benefits of an "extended taxonomy of fitness" in present and future studies concerning human evolution.

  20. Initial adaptation testing of the bidimensionally self-adapting wall of the French T2 wind tunnel, around a three-dimensional object

    NASA Technical Reports Server (NTRS)

    Archambaud, J. P.; Dor, J. B.; Mignosi, A.; Lamarche, L.

    1986-01-01

    The test series was carried out at ONERA/CERT at the T2 wind tunnel in September 1984. The objective of this series was to minimize wall interference through a bidimensional adaptation around the models, inducing tridimensional flows. For this, three different models were used, measuring either the pressures or the forces and moment of pitch (balance). The adaptation was derived from a correction computation in the compressible axisymmetric tridimensional.

  1. Translation, cultural adaptation and field-testing of the Thinking Healthy Program for Vietnam

    PubMed Central

    2014-01-01

    Background Depression and anxiety are prevalent among women in low- and lower-middle income countries who are pregnant or have recently given birth. There is promising evidence that culturally-adapted, evidence-informed, perinatal psycho-educational programs implemented in local communities are effective in reducing mental health problems. The Thinking Healthy Program (THP) has proved effective in Pakistan. The aims were to adapt the THP for rural Vietnam; establish the program’s comprehensibility, acceptability and salience for universal use, and investigate whether administration to small groups of women might be of equivalent effectiveness to administration in home visits to individual women. Methods The THP Handbook and Calendar were made available in English by the program developers and translated into Vietnamese. Cultural adaptation and field-testing were undertaken using WHO guidance. Field-testing of the four sessions of THP Module One was undertaken in weekly sessions with a small group in a rural commune and evaluated using baseline, process and endline surveys. Results The adapted Vietnamese version of the Thinking Healthy Program (THP-V) was found to be understandable, meaningful and relevant to pregnant women, and commune health centre and Women’s Union representatives in a rural district. It was delivered effectively by trained local facilitators. Role-play, brainstorming and small-group discussions to find shared solutions to common problems were appraised as helpful learning opportunities. Conclusions The THP-V is safe and comprehensible, acceptable and salient to pregnant women without mental health problems in rural Vietnam. Delivery in facilitated small groups provided valued opportunities for role-play rehearsal and shared problem solving. Local observers found the content and approach highly relevant to local needs and endorsed the approach as a mental health promotion strategy with potential for integration into local universal maternal

  2. Using Tests Designed to Measure Individual Sensorimotor Subsystem Perfomance to Predict Locomotor Adaptability

    NASA Technical Reports Server (NTRS)

    Peters, B. T.; Caldwell, E. E.; Batson, C. D.; Guined, J. R.; DeDios, Y. E.; Stepanyan, V.; Gadd, N. E.; Szecsy, D. L.; Mulavara, A. P.; Seidler, R. D.; Bloomberg, J. J.

    2014-01-01

    Astronauts experience sensorimotor disturbances during the initial exposure to microgravity and during the readapation phase following a return to a gravitational environment. These alterations may lead to disruption in the ability to perform mission critical functions during and after these gravitational transitions. Astronauts show significant inter-subject variation in adaptive capability following gravitational transitions. The way each individual's brain synthesizes the available visual, vestibular and somatosensory information is likely the basis for much of the variation. Identifying the presence of biases in each person's use of information available from these sensorimotor subsystems and relating it to their ability to adapt to a novel locomotor task will allow us to customize a training program designed to enhance sensorimotor adaptability. Eight tests are being used to measure sensorimotor subsystem performance. Three of these use measures of body sway to characterize balance during varying sensorimotor challenges. The effect of vision is assessed by repeating conditions with eyes open and eyes closed. Standing on foam, or on a support surface that pitches to maintain a constant ankle angle provide somatosensory challenges. Information from the vestibular system is isolated when vision is removed and the support surface is compromised, and it is challenged when the tasks are done while the head is in motion. The integration and dominance of visual information is assessed in three additional tests. The Rod & Frame Test measures the degree to which a subject's perception of the visual vertical is affected by the orientation of a tilted frame in the periphery. Locomotor visual dependence is determined by assessing how much an oscillating virtual visual world affects a treadmill-walking subject. In the third of the visual manipulation tests, subjects walk an obstacle course while wearing up-down reversing prisms. The two remaining tests include direct

  3. COMPARISON OF LUNG ATTENUATION AND HETEROGENEITY BETWEEN CATS WITH EXPERIMENTALLY INDUCED ALLERGIC ASTHMA, NATURALLY OCCURRING ASTHMA AND NORMAL CATS.

    PubMed

    Masseau, Isabelle; Banuelos, Alina; Dodam, John; Cohn, Leah A; Reinero, Carol

    2015-01-01

    Airway remodeling is a prominent feature of feline allergic asthma but requires biopsy for characterization. Computed tomography (CT) has appeal as a minimally invasive diagnostic test. The purpose of this prospective case-control study was to compare indices of airway remodeling between cats with experimentally induced, spontaneous asthma and healthy unaffected cats using CT. We hypothesized that experimental and spontaneous feline asthma would have similar CT airway remodeling characteristics and that these would be significantly different in healthy cats. Experimentally induced asthmatic research cats (n = 5), spontaneously asthmatic pet cats (n = 6), and healthy research cats (n = 5) were scanned unrestrained using a 64-detector row CT scanner. Inspiratory breath-hold CT scans were also performed in experimentally induced asthmatic and healthy cats. Mean ± extent variation of lung attenuation for each cat was determined using an airway inspector software program and CT images were scored for lung heterogeneity by a board-certified veterinary radiologist who was unaware of cat group status. Groups were compared using one-way ANOVA (unrestrained scans) and the Student's t-test (anesthetized scans) with significance defined as P < 0.10. Experimentally asthmatic and spontaneously asthmatic cats had significantly (P = 0.028 and P = 0.073, respectively) increased lung attenuation compared to healthy cats. Heterogeneity scores were higher in experimentally induced asthmatic cat than in healthy cats. Objective quantification of lung heterogeneity and lung volume did not differ among the three groups (P = 0.311, P = 0.181, respectively). Findings supported our hypothesis. Inspiratory breath-hold anesthetized CT scans facilitated discrimination between asthmatic and healthy cats in comparison to unrestrained CT scans.

  4. Fabrication and Testing of Active and Adaptive Cyanate Ester Composite Mirrors

    NASA Technical Reports Server (NTRS)

    Bennett, H. E.

    2004-01-01

    The objective of the NASA/Bennett Optical Research Inc. (BOR) NAS8-02008 Phase II Program, which also incorporated ideas developed under the earlier NASA NAS8-01035 Phase 1 Program, was to develop a large mirror fabrication and test facility with emphasis on producing large, light weight active and adaptive optics. A principle objective was to develop mandrels on which to make large composite graphite-filled cyanate ester mirrors, Deliverables were two of these superpolished lightweight active/adaptive optic composite mirrors, one 12" (approx.1/3 meter) in diameter and one 22" (approx.1/2 meter) in diameter. In addition optical superpolishers for mandrels up to 1.2 meters in diameter, test instruments for determining optical figure and scattered light, novel design actuators for making the composite mirrors both active and adaptive, and passive and active means for measuring actuator performance were developed at BOR. We are now installing a superpolisher capable of producing 3 meter diameter mirror/mandrels. All polishers utilize the principle of centrifugal elutriation and produce superpolished mandrels with surface microroughnesses under 1 nm rms.

  5. Myeloproliferative disease in a cat

    SciTech Connect

    Yates, R.W.; Weller, R.E.; Feldman, B.F.

    1984-10-01

    Myeloproliferative disorders, a complex of cytologic abnormalities arising in the bone marrow, are among domestic animals most frequently recognized in cats but are relatively uncommon. A 4-year-old female Siamese, with splenomegaly and weight loss, was listless, anorectic, pale and dehydrated. A hemogram showed severe, macrocytic normochromic anemia, leukocytosis and reticulocytosis, with abnormally high numbers of nucleated RBC and undifferentiated blast cells. Bone marrow smears contained predominantly undifferentiated blast cells, RBC precursors and myeloblasts. The fluorescent antibody test for FeLV was positive. The cat died 66 days later despite a blood transfusion and chemotherapy. Necropsy confirmed a diagnosis of myeloproliferative disease, with hepatic and splenic invasion. 15 references, 5 figures, 1 table.

  6. Taste rejection of nonnutritive sweeteners in cats.

    PubMed

    Bartoshuk, L M; Jacobs, H L; Nichols, T L; Hoff, L A; Ryckman, J J

    1975-10-01

    Cats reject saccharin and cyclamate and are indifferent to dulcin, although they, like other mammals, prefer sucrose. The rejection threshold for saccharin found in this experiments, .0001 M, is about 2 log steps lower than a previously reported rejection threshold for sodium saccharin. Water produces a taste in cats adapted to their own saliva. The high sodium saccharin threshold may have resulted because the taste of the sodium saccharin was masked by the taste of the water solvent; however, saccharin may also be somewhat more aversive to the cat than sodium saccharin. Saccharin may produce an aversive taste because it stimulates receptor sites sensitive to substances bitter to man as well as those sensitive to sugars. In addition, saccharin may not be an effective stimulus for all sugar-sensitive sites.

  7. PHURBAS: AN ADAPTIVE, LAGRANGIAN, MESHLESS, MAGNETOHYDRODYNAMICS CODE. II. IMPLEMENTATION AND TESTS

    SciTech Connect

    McNally, Colin P.; Mac Low, Mordecai-Mark; Maron, Jason L. E-mail: jmaron@amnh.org

    2012-05-01

    We present an algorithm for simulating the equations of ideal magnetohydrodynamics and other systems of differential equations on an unstructured set of points represented by sample particles. The particles move with the fluid, so the time step is not limited by the Eulerian Courant-Friedrichs-Lewy condition. Full spatial adaptivity is required to ensure the particles fill the computational volume and gives the algorithm substantial flexibility and power. A target resolution is specified for each point in space, with particles being added and deleted as needed to meet this target. We have parallelized the code by adapting the framework provided by GADGET-2. A set of standard test problems, including 10{sup -6} amplitude linear magnetohydrodynamics waves, magnetized shock tubes, and Kelvin-Helmholtz instabilities is presented. Finally, we demonstrate good agreement with analytic predictions of linear growth rates for magnetorotational instability in a cylindrical geometry. This paper documents the Phurbas algorithm as implemented in Phurbas version 1.1.

  8. Experimental characterization of an adaptive aileron: lab tests and FE correlation

    NASA Astrophysics Data System (ADS)

    Amendola, Gianluca; Dimino, Ignazio; Amoroso, Francesco; Pecora, Rosario

    2016-04-01

    Like any other technology, morphing has to demonstrate system level performance benefits prior to implementation onto a real aircraft. The current status of morphing structures research efforts (as the ones, sponsored by the European Union) involves the design of several subsystems which have to be individually tested in order to consolidate their general performance in view of the final integration into a flyable device. This requires a fundamental understanding of the interaction between aerodynamic, structure and control systems. Important worldwide research collaborations were born in order to exchange acquired experience and better investigate innovative technologies devoted to morphing structures. The "Adaptive Aileron" project represents a joint cooperation between Canadian and Italian research centers and leading industries. In this framework, an overview of the design, manufacturing and testing of a variable camber aileron for a regional aircraft is presented. The key enabling technology for the presented morphing aileron is the actuation structural system, integrating a suitable motor and a load-bearing architecture. The paper describes the lab test campaign of the developed device. The implementation of a distributed actuation system fulfills the actual tendency of the aeronautical research to move toward the use of electrical power to supply non-propulsive systems. The aileron design features are validated by targeted experimental tests, demonstrating both its adaptive capability and robustness under operative loads and its dynamic behavior for further aeroelastic analyses. The experimental results show a satisfactory correlation with the numerical expectations thus validating the followed design approach.

  9. A global logrank test for adaptive treatment strategies based on observational studies.

    PubMed

    Li, Zhiguo; Valenstein, Marcia; Pfeiffer, Paul; Ganoczy, Dara

    2014-02-28

    In studying adaptive treatment strategies, a natural question that is of paramount interest is whether there is any significant difference among all possible treatment strategies. When the outcome variable of interest is time-to-event, we propose an inverse probability weighted logrank test for testing the equivalence of a fixed set of pre-specified adaptive treatment strategies based on data from an observational study. The weights take into account both the possible selection bias in an observational study and the fact that the same subject may be consistent with more than one treatment strategy. The asymptotic distribution of the weighted logrank statistic under the null hypothesis is obtained. We show that, in an observational study where the treatment selection probabilities need to be estimated, the estimation of these probabilities does not have an effect on the asymptotic distribution of the weighted logrank statistic, as long as the estimation of the parameters in the models for these probabilities is n-consistent. Finite sample performance of the test is assessed via a simulation study. We also show in the simulation that the test can be pretty robust to misspecification of the models for the probabilities of treatment selection. The method is applied to analyze data on antidepressant adherence time from an observational database maintained at the Department of Veterans Affairs' Serious Mental Illness Treatment Research and Evaluation Center.

  10. Improved Testing Capability and Adaptability Through the Use of Wireless Sensors

    NASA Technical Reports Server (NTRS)

    Solano, Wanda M.

    2003-01-01

    From the first Saturn V rocket booster (S-II-T) testing in 1966 and the routine Space Shuttle Main Engine (SSME) testing beginning in 1975, to more recent test programs such as the X-33 Aerospike Engine, the Integrated Powerhead Development (IPD) program, and the Hybrid Sounding Rocket (HYSR), Stennis Space Center (SSC) continues to be a premier location for conducting large-scale testing. Central to each test program is the capability for sensor systems to deliver reliable measurements and high quality data, while also providing a means to monitor the test stand area to the highest degree of safety and sustainability. Sensor wiring is routed along piping and through cable trenches, making its way from the engine test area, through the test stand area and to the signal conditioning building before final transfer to the test control center. When sensor requirements lie outside the reach of the routine sensor cable routing, the use of wireless sensor networks becomes particularly attractive due to their versatility and ease of installation. As part of an on-going effort to enhance the testing capabilities of Stennis Space Center, the Test Technology and Development group has found numerous applications for its sensor-adaptable wireless sensor suite. While not intended for critical engine measurements or control loops, in-house hardware and software development of the sensor suite can provide improved testing capability for a range of applications including the safety monitoring of propellant storage barrels and as an experimental test-bed for embedded health monitoring paradigms.

  11. Distortion product otoacoustic emissions in young adult and geriatric cats.

    PubMed

    Strain, George M; McGee, Kain A

    2017-03-01

    Recordings of distortion product otoacoustic emissions (DPOAEs) were taken from 15 geriatric cats (mean age ± standard deviation, SD, 13.6 ± 2.7 years; range 10.2-19.4 years) and 12 young adult control cats (mean ± SD 4.6 ± 0.5 years; range 3.4-5 years) to identify frequency-specific age-related changes in cochlear responses. Recordings were performed for primary frequencies from 2 to 12 kHz in 2 kHz increments. Cats were considered to be geriatric > 11.9 ± 1.9 years of age. Brainstem auditory evoked response (BAER) recordings were also made for subjective comparison with DPOAE responses. No differences in DPOAE response amplitudes were observed at any tested frequency in geriatric cats compared to control cats, reflecting an apparent absence of loss of cochlear outer hair cells along the length of the cochlea. No linear regression relationships were found for DPOAE response amplitude versus age in geriatric cats, despite the progressive nature of age-related hearing loss in other species. The absence of reductions in response at any of the tested frequencies in cats within the age span where cats are considered to be geriatric indicates that age-related hearing loss, if it does develop in cats, begins later in the life span of cats than in dogs or human beings.

  12. Design and Flight Tests of an Adaptive Control System Employing Normal-Acceleration Command

    NASA Technical Reports Server (NTRS)

    McNeill, Water E.; McLean, John D.; Hegarty, Daniel M.; Heinle, Donovan R.

    1961-01-01

    An adaptive control system employing normal-acceleration command has been designed with the aid of an analog computer and has been flight tested. The design of the system was based on the concept of using a mathematical model in combination with a high gain and a limiter. The study was undertaken to investigate the application of a system of this type to the task of maintaining nearly constant dynamic longitudinal response of a piloted airplane over the flight envelope without relying on air data measurements for gain adjustment. The range of flight conditions investigated was between Mach numbers of 0.36 and 1.15 and altitudes of 10,000 and 40,000 feet. The final adaptive system configuration was derived from analog computer tests, in which the physical airplane control system and much of the control circuitry were included in the loop. The method employed to generate the feedback signals resulted in a model whose characteristics varied somewhat with changes in flight condition. Flight results showed that the system limited the variation in longitudinal natural frequency of the adaptive airplane to about half that of the basic airplane and that, for the subsonic cases, the damping ratio was maintained between 0.56 and 0.69. The system also automatically compensated for the transonic trim change. Objectionable features of the system were an exaggerated sensitivity of pitch attitude to gust disturbances, abnormally large pitch attitude response for a given pilot input at low speeds, and an initial delay in normal-acceleration response to pilot control at all flight conditions. The adaptive system chatter of +/-0.05 to +/-0.10 of elevon at about 9 cycles per second (resulting in a maximum airplane normal-acceleration response of from +/-0.025 g to +/- 0.035 g) was considered by the pilots to be mildly objectionable but tolerable.

  13. A Cross-Cultural Adaptation of the Sniffin' Sticks Olfactory Identification Test for US children.

    PubMed

    Cavazzana, Annachiara; Wesarg, Christiane; Schriever, Valentin A; Hummel, Thomas; Lundström, Johan N; Parma, Valentina

    2017-02-01

    Disorders associated with smell loss are common in adolescents. However, current odor identification tests focus on children from age 6 and older and no cross-cultural test has to date been validated and fully implemented. Here, we aimed to investigate how 3-to-11-year-old US children performed to an adapted and shortened (11 odors instead of 14) version of a European odor identification test-the Sniffin' Kids (Schriever VA, Mori E, Petters W, Boerner C, Smitka M, Hummel T. 2014. The "Sniffin'Kids" test: a 14-item odor identification test for children. Plos One. 9:e101086.). Results confirmed that cued odor identification performance increases with age and revealed little to no differences between girls and boys. Scores below 3 and below 6 may raise hyposmia concerns in US children aged 3-7 years and 8-10 years, respectively. Even though the completion rate of the task reached the 88%, suggesting that children below age 5 were able to finish the test, their performance was relatively poor. In comparing the overall identification performance of US children with that of German children, for whom the test was specifically developed, significant differences emerged, with higher scores obtained by the German sample. Analysis of errors indicated that a lack of semantic knowledge for the olfactory-presented objects may be at the root of poor identification skills in US children and therefore constitutes a problem in the development of an odor identification test for younger children valid across cultures.

  14. Metabolizable energy intake of client-owned adult cats.

    PubMed

    Thes, M; Koeber, N; Fritz, J; Wendel, F; Dobenecker, B; Kienzle, E

    2015-12-01

    A retrospective analysis of the metabolizable energy (ME) intake of privately owned pet cats from the authors' nutrition consultation practice (years 2007-2011) was carried out to test whether current recommendations are suitable for pet cats. Data of 80 adult cats (median age: 9.0 years, median deviation from ideal weight: +22.5%, majority neutered) at maintenance were available. Six percentage of the cats were healthy and the others were affected by various chronic diseases. A standardized questionnaire was used, cat owners weighed cat and food. For ration calculation, the software Diet Check Munich(™) was used (ME prediction according to National Research Council, 2006: Nutrient Requirements of Dogs and Cats. National Academy Press, Washington, DC). Data were analysed for the factors deviation from ideal weight, breed, age, gender, disease and type of feeding [prepared food (dry, wet) vs. home-made]. Over- or underweight were defined as ≥15% deviation from ideal body weight (BW) according to Kienzle and Moik (British Journal of Nutrition 2011, 106, Suppl 1: S113). Cat owner's estimation of ideal BW was higher than literature data from Kienzle and Moik (2011). Based on literature data, 26.3% of the pet cats were normal weight, 63.7% overweight and 10% underweight. The mean ME intake of all adult cats amounted to 0.40 ± 0.14 MJ/kg actual BW(0.67) (n = 80). When the data were analysed according to normal, over- and underweight, there was a significant effect with normal weight cats eating 0.46 MJ/kg BW(0.67) . Underweight cats ate even more (0.49 MJ/kg BW(0.67) ), whereas overweight cats ate considerably less (0.36 MJ/kg BW(0.67) ). The other factors had no influence on ME intake of adult cats.

  15. Adaptation of the cellscan technique for the SCM test in breast cancer.

    PubMed

    Rahmani, H; Deutsch, M; Ron, I; Gerbat, S; Tirosh, R; Weinreb, A; Chaitchik, S; Lalchuk, S

    1996-09-01

    The value of the SCM (Structuredness of Cytoplasmic Matrix) cancer test, a procedure based on the detection of differences in lymphocyte activation in the presence and absence of cancer, has remained controversial, with inconsistent results having been reported among investigators. The Cellscan, a high-precision static cytometer system, has been designed to perform the SCM test; the apparatus facilitates the polarisation measurements and can examine cells which have been separated by simpler procedures than were originally described. In this study, using methods and diagnostic criteria adapted for the Cellscan system in a hospital environment, the SCM test correctly classified over 90% (76/80) of patients with breast cancer and differentiated over 90% (72/73) of individuals without cancer.

  16. I've Fallen and I Can't Get Up: Can High Ability Students Recover From Early Mistakes in CAT?

    PubMed

    Rulison, Kelly L; Loken, Eric

    2009-03-01

    A difficult result to interpret in Computerized Adaptive Tests (CATs) occurs when an ability estimate initially drops and then ascends continuously until the test ends, suggesting that the true ability may be higher than implied by the final estimate. We explain why this asymmetry occurs and show that early mistakes by high ability students can lead to considerable underestimation, even in tests with 45 items. The opposite response pattern, where low ability students start with lucky guesses, leads to much less bias. We show that using Barton and Lord's (1981) four-parameter model and a less informative prior can lower bias and RMSE for high ability students with a poor start, as the CAT algorithm ascends more quickly after initial underperformance. We also show that the 4PM slightly outperforms a CAT in which less discriminating items are initially used. The practical implications and relevance for psychological measurement more generally are discussed.

  17. Cat tongue Velcro

    NASA Astrophysics Data System (ADS)

    Noel, Alexis; Martinez, Andrea; Jung, Hyewon; Tsai, Ting-Wen; Hu, David

    2016-11-01

    A cat's tongue is covered in an array of spines called papillae. These spines are thought to be used in grooming and rasping meat from bones of prey, although no mechanism has been given. We use high-speed video to film a cat removing cat food deeply wedged into a 3-D printed fur mat. We show that the spines on the tongue act as Velcro for particles. The tongue itself is highly elastic. As the cat presses it against a substrate, the tongue flattens and the spines separate. When the tongue is removed from the substrate the spines come together, wedging particles between them. This elasticity-driven entrapment permits the surface of the tongue to act as a carrier for hard to reach particles, and to increase the efficacy of grooming and feeding.

  18. Implementation of an Adaptive Controller System from Concept to Flight Test

    NASA Technical Reports Server (NTRS)

    Larson, Richard R.; Burken, John J.; Butler, Bradley S.

    2009-01-01

    The National Aeronautics and Space Administration Dryden Flight Research Center (Edwards, California) is conducting ongoing flight research using adaptive controller algorithms. A highly modified McDonnell-Douglas NF-15B airplane called the F-15 Intelligent Flight Control System (IFCS) was used for these algorithms. This airplane has been modified by the addition of canards and by changing the flight control systems to interface a single-string research controller processor for neural network algorithms. Research goals included demonstration of revolutionary control approaches that can efficiently optimize aircraft performance for both normal and failure conditions, and to advance neural-network-based flight control technology for new aerospace systems designs. Before the NF-15B IFCS airplane was certified for flight test, however, certain processes needed to be completed. This paper presents an overview of these processes, including a description of the initial adaptive controller concepts followed by a discussion of modeling formulation and performance testing. Upon design finalization, the next steps are: integration with the system interfaces, verification of the software, validation of the hardware to the requirements, design of failure detection, development of safety limiters to minimize the effect of erroneous neural network commands, and creation of flight test control room displays to maximize human situational awareness.

  19. Fatal big cat attacks.

    PubMed

    Cohle, S D; Harlan, C W; Harlan, G

    1990-09-01

    Two cases of fatal attacks by large cats are presented. In the first case, a 30-year-old female zoo worker was attacked by a jaguar that had escaped its cage. In the second case, a 2-year-old girl was fatally injured by her father's pet leopard. The pattern of injuries in these cases is nearly identical to those of these cats' prey in the wild.

  20. A trap, neuter, and release program for feral cats on Prince Edward Island.

    PubMed

    Gibson, Karen L; Keizer, Karen; Golding, Christine

    2002-09-01

    A new program to address the feral cat population on Prince Edward Island was undertaken during the spring and summer of 2001. Feral cats from specific geographic areas were trapped, sedated, and tested for feline leukemia virus and feline immunodeficiency virus. Healthy cats were neutered, dewermed, vaccinated, tattooed, and released to their area of origin. A total of 185 cats and kittens were trapped and tested during a 14-week period; 158 cats and kittens as young as 6 weeks of age were neutered and released. Twenty-three adult cats were positive for feline leukemia virus, feline immunodeficiency virus, or both, and were euthanized.

  1. Cat Scratch Disease: Expanded Spectrum

    PubMed Central

    Aziz, Hassan A.; Plesec, Thomas P.; Sabella, Camille; Udayasankar, Unni K.; Singh, Arun D.

    2016-01-01

    Background To expand the spectrum of ophthalmic manifestations in cat scratch disease. Methods Case report. Results A 7-year-old male was referred for evaluation of his left optic disc after failing vision screening test at school. His visual acuity was 20/20 OD and light perception OS. Fundus examination showed a left optic disc lesion associated with an exudative retinal detachment and vitreous seeding. Ultrasonography revealed a 7 × 7.5 × 3.8 mm lesion with a possible 6.3 mm of retrolaminar extension into the substance of the optic nerve. Brain MRI did not show evidence of optic nerve involvement but revealed a 6-mm nodule of the pineal gland suggestive of a pineoblastoma. Enucleation was performed and histopathology revealed a suppurative granulomatous inflammation suggestive of Bartonella infection. Upon further questioning, the patient had recent exposure to kittens with areas of cat scratches along both of his arms. He was subsequently referred to and treated with a 2-week course of trimethoprim-sulfamethoxazole and rifampin by the pediatric infectious disease specialist. Repeat brain MRI showed interval total resolution of enlarged pineal gland. Conclusion: Optic nerve granulomas are a rare presentation of cat scratch disease and could potentially masquerade as retinoblastoma. PMID:27843905

  2. Development and field testing of a 15-kv class adaptive var compensator

    SciTech Connect

    El-Sharkawi, M.A.; Dong, M.; Huang, T.; Szofran, A.; Andexler, G.; Venkata, S.S.; Butler, N.; Rodriguez, A.; Kerszenbaum

    1995-10-01

    A 15-kV class Adaptive Var Compensator (AVC) is developed and field tested. The AVC is a solid stat switched, binary stepped capacitor bank, used to compensate any rapidly changing reactive demand within one-half cycle without introducing transients of harmonics. The main features of the AVC are introduced followed by an historical evolution. A general description of each major module is presented and modifications as development proceeded are shown. Results from two industrial site installations are also presented showing the adverse conditions in which the AVC will successfully operate.

  3. Testing Refinement Criteria in Adaptive Discontinuous Galerkin Simulations of Dry Atmospheric Convection

    DTIC Science & Technology

    2011-12-22

    Testing refinement criteria in adaptive Discontinuous Galerkin simulations of dry atmospheric convection Andreas Müllera,∗, Jörn Behrensb, Francis X...mainz.de (Andreas Müller), joern.behrens@zmaw.de (Jörn Behrens), fxgirald@nps.edu ( Francis X. Giraldo), vwirth@uni-mainz.de (Volkmar Wirth) Preprint...formulation and accuracy, Mon. Weather Rev. 120 (1992) 1675–1706. [3] D. P. Bacon , N. N. Ahmad, Z. Boybeyi, T. J. Dunn, M. S. Hall, P. C. S. Lee, R. A

  4. Adaptation of the KeratinoSens™ skin sensitisation test to animal-product-free cell culture.

    PubMed

    Belot, Nathalie; Sim, Bushra; Longmore, Christopher Longmore; Roscoe, Lottie; Treasure, Carol

    2017-03-16

    Skin sensitisation is the process by which a substance leads to an allergic reaction following skin contact. The process has been described as an adverse outcome pathway (AOP), including several key events, from skin penetration and covalent protein binding, to keratinocyte activation, dendritic cell activation and T-lymphocyte proliferation. The in vitro assay KeratinoSens™ measures the activation of keratinocytes. It is fully accepted at a regulatory level (OECD TG 442d) and appropriate for compliance with a range of legislation including the EU Cosmetics Regulation, REACH, and the CLP Regulation. Currently, many in vitro methods use animal-derived components in the cell culture systems. Many stakeholders in the cosmetics industry have both scientific and ethical concerns relating to this issue and have stated a strong preference for fully human in vitro test systems. We have adapted the KeratinoSensTM method to animal product-free conditions, and carried out an in-house validation with 21 reference substances, including those listed in the Performance Standards associated with OECD TG442d. The modified method was shown to be totally equivalent to the Validated Reference Method (VRM), with comparable values for accuracy (85.7%), sensitivity (84.6%) and specificity (87.5%), and all acceptance criteria being met. In Europe, data generated by the adapted method may be used in REACH submissions, and we are now seeking approval to list the adaptation in OECD TG 442d, enabling formal compliance with a range of global regulations.

  5. Testing Local Adaptation in a Natural Great Tit-Malaria System: An Experimental Approach

    PubMed Central

    Jenkins, Tania; Delhaye, Jessica; Christe, Philippe

    2015-01-01

    Finding out whether Plasmodium spp. are coevolving with their vertebrate hosts is of both theoretical and applied interest and can influence our understanding of the effects and dynamics of malaria infection. In this study, we tested for local adaptation as a signature of coevolution between malaria blood parasites, Plasmodium spp. and its host, the great tit, Parus major. We conducted a reciprocal transplant experiment of birds in the field, where we exposed birds from two populations to Plasmodium parasites. This experimental set-up also provided a unique opportunity to study the natural history of malaria infection in the wild and to assess the effects of primary malaria infection on juvenile birds. We present three main findings: i) there was no support for local adaptation; ii) there was a male-biased infection rate; iii) infection occurred towards the end of the summer and differed between sites. There were also site-specific effects of malaria infection on the hosts. Taken together, we present one of the few experimental studies of parasite-host local adaptation in a natural malaria system, and our results shed light on the effects of avian malaria infection in the wild. PMID:26555892

  6. Head size, weaponry, and cervical adaptation: Testing craniocervical evolutionary hypotheses in Ceratopsia.

    PubMed

    VanBuren, Collin S; Campione, Nicolás E; Evans, David C

    2015-07-01

    The anterior cervical vertebrae form the skeletal connection between the cranial and postcranial skeletons in higher tetrapods. As a result, the morphology of the atlas-axis complex is likely to be shaped by selection pressures acting on either the head or neck. The neoceratopsian (Reptilia:Dinosauria) syncervical represents one of the most highly modified atlas-axis regions in vertebrates, being formed by the complete coalescence of the three most anterior cervical vertebrae. In ceratopsids, the syncervical has been hypothesized to be an adaptation to support a massive skull, or to act as a buttress during intraspecific head-to-head combat. Here, we test these functional/adaptive hypotheses within a phylogenetic framework and critically examine the previously proposed methods for quantifying relative head size in the fossil record for the first time. Results indicate that neither the evolution of cranial weaponry nor large head size correlates with the origin of cervical fusion in ceratopsians, and we, therefore, reject both adaptive hypotheses for the origin of the syncervical. Anterior cervical fusion has evolved independently in a number of amniote clades, and further research on extant groups with this peculiar anatomy is needed to understand the evolutionary basis for cervical fusion in Neoceratopsia.

  7. Testing Local Adaptation in Five Populations of Hyalella azteca in Northern Alberta's Oil Sands Region.

    PubMed

    Beery, Steven R; Gauthier, Patrick T; Pyle, Gregory G

    2017-02-01

    Canada's oil sands hold the third largest petroleum reserves worldwide and have experienced rapid economic growth. The oil sands region provides an ideal location for studying local adaptations through reciprocal transplant (RT) because populations within the region have been historically exposed to naturally occurring bitumen. Our objectives were to (1) determine if Hyalella azteca from habitats within the oil sands region exhibited increased tolerance to constituents associated with industrial bitumen extraction compared with H. azteca from habitats outside the region; and (2) determine if any observed tolerance was attributable to local adaptation. Five populations of H. azteca were reciprocally transplanted from reclaimed and reference wetlands: four from local wetlands plus one naïve laboratory population. Survival, toxicity, and behaviour were measured before and after the RT period. Survival varied by population and site. These results show that the differences in responses among populations are likely not attributable to local adaptation and that laboratory populations of H. azteca provide ecologically relevant results when tested in the field.

  8. Hardware and operating features of the adaptive wall test section for the 0.3-meter transonic cryogenic tunnel

    NASA Technical Reports Server (NTRS)

    Mineck, Raymond E.

    1989-01-01

    A 13- by 13-inch adaptive wall test section was installed in the Langley 0.3-Meter Transonic Cryogenic Tunnel circuit. This test section has four solid walls and is configured for two-dimensional airfoil testing. The top and bottom walls are flexible and movable, whereas the sidwalls are rigid and fixed. The test section has a turntable to support airfoil models, a survey mechanism to probe the model wake, and provisions for a sidewall boundary-layer-control system. Details of the adaptive wall test section, the tunnel circuit modifications, the supporting instrumentation, the monitoring and control hardware, and the wall adaptation strategy are discussed. Sample results of shakedown tests with the test section empty and with an airfoil installed are also included.

  9. CR-Calculus and adaptive array theory applied to MIMO random vibration control tests

    NASA Astrophysics Data System (ADS)

    Musella, U.; Manzato, S.; Peeters, B.; Guillaume, P.

    2016-09-01

    Performing Multiple-Input Multiple-Output (MIMO) tests to reproduce the vibration environment in a user-defined number of control points of a unit under test is necessary in applications where a realistic environment replication has to be achieved. MIMO tests require vibration control strategies to calculate the required drive signal vector that gives an acceptable replication of the target. This target is a (complex) vector with magnitude and phase information at the control points for MIMO Sine Control tests while in MIMO Random Control tests, in the most general case, the target is a complete spectral density matrix. The idea behind this work is to tailor a MIMO random vibration control approach that can be generalized to other MIMO tests, e.g. MIMO Sine and MIMO Time Waveform Replication. In this work the approach is to use gradient-based procedures over the complex space, applying the so called CR-Calculus and the adaptive array theory. With this approach it is possible to better control the process performances allowing the step-by-step Jacobian Matrix update. The theoretical bases behind the work are followed by an application of the developed method to a two-exciter two-axis system and by performance comparisons with standard methods.

  10. Computed tomography of nonanesthetized cats with upper airway obstruction.

    PubMed

    Stadler, Krystina; O'Brien, Robert

    2013-01-01

    Upper airway obstruction is a potentially life-threatening problem in cats and for which a noninvasive, sensitive method rapid diagnosis is needed. The purposes of this prospective study were to describe a computed tomography (CT) technique for nonanesthetized cats with upper airway obstruction, CT characteristics of obstructive diseases, and comparisons between CT findings and findings from other diagnostic tests. Ten cats with clinical signs of upper airway obstruction were recruited for the study. Four cats with no clinical signs of upper airway obstruction were recruited as controls. All cats underwent computed tomography imaging without sedation or anesthesia, using a 16-slice helical CT scanner and a previously described transparent positional device. Three-dimensional (3D) internal volume rendering was performed on all CT image sets and 3D external volume rendering was also performed on cats with evidence of mass lesions. Confirmation of upper airway obstruction was based on visual laryngeal examination, endoscopy, fine-needle aspirate, biopsy, or necropsy. Seven cats were diagnosed with intramural upper airway masses, two with laryngotracheitis, and one with laryngeal paralysis. The CT and 3D volume-rendered images identified lesions consistent with upper airway disease in all cats. In cats with mass lesions, CT accurately identified the mass and location. Findings from this study supported the use of CT imaging as an effective technique for diagnosing upper airway obstruction in nonanesthetized cats.

  11. Assessment of Postflight Locomotor Performance Utilizing a Test of Functional Mobility: Strategic and Adaptive Responses

    NASA Technical Reports Server (NTRS)

    Warren, L. E.; Mulavara, A. P.; Peters, B. T.; Cohen, H. S.; Richards, J. T.; Miller, C. A.; Brady, R.; Ruttley, T. M.; Bloomberg, J. J.

    2006-01-01

    Space flight induces adaptive modification in sensorimotor function, allowing crewmembers to operate in the unique microgravity environment. This adaptive state, however, is inappropriate for a terrestrial environment. During a re-adaptation period upon their return to Earth, crewmembers experience alterations in sensorimotor function, causing various disturbances in perception, spatial orientation, posture, gait, and eye-head coordination. Following long duration space flight, sensorimotor dysfunction would prevent or extend the time required to make an emergency egress from the vehicle; compromising crew safety and mission objectives. We are investigating two types of motor learning that may interact with each other and influence a crewmember's ability to re-adapt to Earth's gravity environment. In strategic learning, crewmembers make rapid modifications in their motor control strategy emphasizing error reduction. This type of learning may be critical during the first minutes and hours after landing. In adaptive learning, long-term plastic transformations occur, involving morphological changes and synaptic modification. In recent literature these two behavioral components have been associated with separate brain structures that control the execution of motor strategies: the strategic component was linked to the posterior parietal cortex and the adaptive component was linked to the cerebellum (Pisella, et al. 2004). The goal of this paper was to demonstrate the relative contributions of the strategic and adaptive components to the re-adaptation process in locomotor control after long duration space flight missions on the International Space Station (ISS). The Functional Mobility Test (FMT) was developed to assess crewmember s ability to ambulate postflight from an operational and functional perspective. Sixteen crewmembers were tested preflight (3 sessions) and postflight (days 1, 2, 4, 7, 25) following a long duration space flight (approx 6 months) on the ISS. We

  12. Validity and cost-effectiveness of cone adaptation test as a screening tool to detect retinitis pigmentosa

    PubMed Central

    Deshpande, Rahul; Save, Prajakta; Deshpande, Madan; Shegunashi, Mahadev; Chougule, Marium; Khandekar, Rajiv

    2016-01-01

    Background: The cone adaptation test is to detect retinitis pigmentosa (RP) cases confirmed by electroretinogram (ERG). We present the validity and cost-effectiveness of cone adaptation test as a screening tool for detecting RP. Methods: This cross-sectional study was conducted between November 2013 and December 2013. All RP cases diagnosed by ophthalmologists of H. V. Desai Eye Hospital in the last 5 years were participated in this study. The cone adaptation test was done in photopic and scotopic illumination. Failed test means 10 s or more to complete the test under scotopic illumination. A technician who was masked for cone adaptation test finding carried out ERG. Demographics, symptoms, and history of treatment were inquired. Those with flat ERG wave in scotopic condition and corresponding clinical findings were defined as having RP. Sensitivity, specificity, and false-positive and false-negative parameters of validity were estimated. The unit cost of performing test and ERG was calculated. Results: All 32 RP patients (28 male, age median 23.5 ± 14.5 years) had a vision more than 6/60 and flat wave in ERG under mesopic/scotopic illumination. Thirty-one participants failed cone adaptation test. The sensitivity was 31/32 × 100 = 97%. The specificity was 100%. There was no false-positive case. Consanguinity rate among parents was 43%. The cost of testing one child using “cone adaptation test kit” was 2.5 US $. The unit cost of diagnosing RP using ERG was 10 US $. Conclusion: Cone adaptation is a valid and cost-effective screening tool test for RP. The consanguinity rate among parents of an RP patient was high. PMID:27843226

  13. Comparison of metabolic expenditure during CAEP versus a test adapted to aerobic capacity (Harbor test) in elderly healthy individuals.

    PubMed

    Page, E; Bonnet, J L; Durand, C

    2000-11-01

    Cardiopulmonary exercise tests are frequently used to test rate responsive pacemakers. The chronotropic assessment exercise protocol (CAEP) has been specifically proposed for the evaluation of rate responsive pacing systems. A mathematical method, based on CAEP measurements, was developed with a view of normalizing the exercise induced metabolic response. CAEP was compared to a tailored protocol (Harbor), adapted to the metabolic capacity of each patient. Harbor was set to keep the exercise duration within 10 minutes and achieve a workload as linear as possible. Metabolic parameters were continuously recorded by a cardiopulmonary system. Those data were used in the construction of slopes by the normalization method. The results of the tests performed in 16 elderly healthy patients showed no differences in metabolic or functional parameters. Slopes of the mathematical model were comparable (1.09 +/- 0.16 for CAEP vs 1.07 +/- 0.17 for Harbor), though both were higher than the value of 1, defined as normal. In both cases, linearity was confirmed by the coefficient of correlation (0.98 +/- 0.02 for CAEP and Harbor). In conclusion, no significant differences were found in the outcomes of the two protocols. Higher values of the slopes with the normalization method can be explained by the definition of the maximal predicted heart rate as 220--age, which is probably not appropriate for elderly, healthy, active subjects.

  14. Assessment in the Twenty-first Century: A Role of Computerised Adaptive Testing in National Curriculum Subjects..

    ERIC Educational Resources Information Center

    Cowan, Pamela; Morrison, Hugh

    2001-01-01

    Highlights problems associated with pen-and-paper testing, recommending a computerized adaptive testing system which measures students' abilities against the levels of the United Kingdom National Curriculum in mathematics. The current prototype of this system can be used on a school's network. Results are issued at the time of testing, and…

  15. Adapting Tests of Sign Language Assessment for Other Sign Languages--A Review of Linguistic, Cultural, and Psychometric Problems

    ERIC Educational Resources Information Center

    Haug, Tobias; Mann, Wolfgang

    2008-01-01

    Given the current lack of appropriate assessment tools for measuring deaf children's sign language skills, many test developers have used existing tests of other sign languages as templates to measure the sign language used by deaf people in their country. This article discusses factors that may influence the adaptation of assessment tests from…

  16. Psychopathology scale of the Hutt adaptation of the Bender-Gestalt Test: reliability.

    PubMed

    Miller, L J; Hutt, M L

    1975-04-01

    The test-retest reliability of the Hutt Adaptation of the Bender-Gestalt test was explored with a population of 40 process schizophrenics over a two-week interval. The total Psychopathology Scale Score was found to have high retest reliability for both male and female patients (rho = .87 for males and .83 for females). Moreover the three major components for the Scale were found to have high reliability, and fairly high reliabilities were obtained for patients scoring high as well as low on the Scale. Interjudge reliability was also found to be very high (rho = .895), confirming previous studies in this respect. On these grounds, the Scale offers promise both for clinical and research purposes.

  17. Flight control system development and flight test experience with the F-111 mission adaptive wing aircraft

    NASA Technical Reports Server (NTRS)

    Larson, R. R.

    1986-01-01

    The wing on the NASA F-111 transonic aircraft technology airplane was modified to provide flexible leading and trailing edge flaps. This wing is known as the mission adaptive wing (MAW) because aerodynamic efficiency can be maintained at all speeds. Unlike a conventional wing, the MAW has no spoilers, external flap hinges, or fairings to break the smooth contour. The leading edge flaps and three-segment trailing edge flaps are controlled by a redundant fly-by-wire control system that features a dual digital primary system architecture providing roll and symmetric commands to the MAW control surfaces. A segregated analog backup system is provided in the event of a primary system failure. This paper discusses the design, development, testing, qualification, and flight test experience of the MAW primary and backup flight control systems.

  18. Illustration of MIMIC-Model DIF Testing with the Schedule for Nonadaptive and Adaptive Personality

    PubMed Central

    Oltmanns, Thomas F.; Turkheimer, Eric

    2010-01-01

    This research provides an example of testing for differential item functioning (DIF) using multiple indicator multiple cause (MIMIC) structural equation models. True/False items on five scales of the Schedule for Nonadaptive and Adaptive Personality (SNAP) were tested for uniform DIF in a sample of Air Force recruits with groups defined by gender and ethnicity. Uniform DIF exists when an item is more easily endorsed for one group than the other, controlling for group mean differences on the variable under study. Results revealed significant DIF for many SNAP items and some effects were quite large. Differentially-functioning items can produce measurement bias and should be either deleted or modeled as if separate items were administered to different groups. Future research should aim to determine whether the DIF observed here holds for other samples. PMID:20442793

  19. Smart monitoring system based on adaptive current control for superconducting cable test

    NASA Astrophysics Data System (ADS)

    Arpaia, Pasquale; Ballarino, Amalia; Daponte, Vincenzo; Montenero, Giuseppe; Svelto, Cesare

    2014-12-01

    A smart monitoring system for superconducting cable test is proposed with an adaptive current control of a superconducting transformer secondary. The design, based on Fuzzy Gain Scheduling, allows the controller parameters to adapt continuously, and finely, to the working variations arising from transformer nonlinear dynamics. The control system is integrated in a fully digital control loop, with all the related benefits, i.e., high noise rejection, ease of implementation/modification, and so on. In particular, an accurate model of the system, controlled by a Fuzzy Gain Scheduler of the superconducting transformer, was achieved by an experimental campaign through the working domain at several current ramp rates. The model performance was characterized by simulation, under all the main operating conditions, in order to guide the controller design. Finally, the proposed monitoring system was experimentally validated at European Organization for Nuclear Research (CERN) in comparison to the state-of-the-art control system [P. Arpaia, L. Bottura, G. Montenero, and S. Le Naour, "Performance improvement of a measurement station for superconducting cable test," Rev. Sci. Instrum. 83, 095111 (2012)] of the Facility for the Research on Superconducting Cables, achieving a significant performance improvement: a reduction in the system overshoot by 50%, with a related attenuation of the corresponding dynamic residual error (both absolute and RMS) up to 52%.

  20. Development and Flight Testing of an Adaptable Vehicle Health-Monitoring Architecture

    NASA Technical Reports Server (NTRS)

    Woodard, Stanley E.; Coffey, Neil C.; Gonzalez, Guillermo A.; Woodman, Keith L.; Weathered, Brenton W.; Rollins, Courtney H.; Taylor, B. Douglas; Brett, Rube R.

    2003-01-01

    Development and testing of an adaptable wireless health-monitoring architecture for a vehicle fleet is presented. It has three operational levels: one or more remote data acquisition units located throughout the vehicle; a command and control unit located within the vehicle; and a terminal collection unit to collect analysis results from all vehicles. Each level is capable of performing autonomous analysis with a trained adaptable expert system. The remote data acquisition unit has an eight channel programmable digital interface that allows the user discretion for choosing type of sensors; number of sensors, sensor sampling rate, and sampling duration for each sensor. The architecture provides framework for a tributary analysis. All measurements at the lowest operational level are reduced to provide analysis results necessary to gauge changes from established baselines. These are then collected at the next level to identify any global trends or common features from the prior level. This process is repeated until the results are reduced at the highest operational level. In the framework, only analysis results are forwarded to the next level to reduce telemetry congestion. The system's remote data acquisition hardware and non-analysis software have been flight tested on the NASA Langley B757's main landing gear.

  1. Smart monitoring system based on adaptive current control for superconducting cable test

    SciTech Connect

    Arpaia, Pasquale; Ballarino, Amalia; Montenero, Giuseppe; Daponte, Vincenzo; Svelto, Cesare

    2014-12-15

    A smart monitoring system for superconducting cable test is proposed with an adaptive current control of a superconducting transformer secondary. The design, based on Fuzzy Gain Scheduling, allows the controller parameters to adapt continuously, and finely, to the working variations arising from transformer nonlinear dynamics. The control system is integrated in a fully digital control loop, with all the related benefits, i.e., high noise rejection, ease of implementation/modification, and so on. In particular, an accurate model of the system, controlled by a Fuzzy Gain Scheduler of the superconducting transformer, was achieved by an experimental campaign through the working domain at several current ramp rates. The model performance was characterized by simulation, under all the main operating conditions, in order to guide the controller design. Finally, the proposed monitoring system was experimentally validated at European Organization for Nuclear Research (CERN) in comparison to the state-of-the-art control system [P. Arpaia, L. Bottura, G. Montenero, and S. Le Naour, “Performance improvement of a measurement station for superconducting cable test,” Rev. Sci. Instrum.83, 095111 (2012)] of the Facility for the Research on Superconducting Cables, achieving a significant performance improvement: a reduction in the system overshoot by 50%, with a related attenuation of the corresponding dynamic residual error (both absolute and RMS) up to 52%.

  2. [Motor adaptation in the Bielschowsky head-tilt test in cases of superior oblique palsy].

    PubMed

    Ohtsuki, H; Kishimoto, F; Kobashi, R; Watanabe, S; Okano, M; Furuse, H

    1992-08-01

    To elucidate a motor adaptation phenomenon in the Bielschowsky head-tilt test in cases of superior oblique palsy, a gain of the otolith-ocular reflex was studied. The amplitude of ocular counter-rolling (OCR) of the non-paretic eye was measured with a photographic method, using limbal conjunctival marks as landmarks which were marked with indigo carmine. The average preoperative OCR of the non-paretic eye was 10.49 degrees at 30 degrees of head tilt to both sides, but after corrective surgery in the paretic eye the OCR of the non-paretic eye decreased to 8.43 degrees. To clarify the relation between OCR, duration of palsy and vertical deviation of the Bielschowsky head-tilt test (BHP), which was the difference of vertical deviation measured with the head tilted to the left and right shoulders at an angle of 30 degrees, the BHP/OCR ratio was calculated. We found no relation between BHP and OCR, but the BHP/OCR ratio increased proportionally in cases of long-standing palsy, From these results an increased BHP/OCR ratio could be an adaptive phenomenon caused by secondary innervational changes or muscle contracture to minimizing the contralateral head tilt to maintain binocular single vision.

  3. Design, Fabrication, and Testing of SMA Enabled Adaptive Chevrons for Jet Noise Reduction

    NASA Technical Reports Server (NTRS)

    Turner, Travis L.; Buehrle, Ralph D.; Cano, Roberto J.; Fleming, Gary A.

    2004-01-01

    This study presents the status and results from an effort to design, fabricate, and test an adaptive jet engine chevron concept based upon embedding shape memory alloy (SMA) actuators in a composite laminate, termed a SMA hybrid composite (SMAHC). The approach for fabricating the adaptive SMAHC chevrons involves embedding prestrained Nitinol actuators on one side of the mid-plane of the composite laminate such that thermal excitation generates a thermal moment and deflects the structure. A glass-epoxy pre-preg/Nitinol ribbon material system and a vacuum hot press consolidation approach are employed. A versatile test system for control and measurement of the chevron deflection performance is described. Projection moire interferometry (PMI) is used for global deformation measurement and infrared (IR) thermography is used for 2-D temperature measurement and feedback control. A recently commercialized constitutive model for SMA and SMAHC materials is used in the finite element code ABAQUS to perform nonlinear static analysis of the chevron prototypes. Excellent agreement is achieved between the predicted and measured chevron deflection performance, thereby validating the design tool. Although the performance results presented in this paper fall short of the requirement, the concept is proven and an approach for achieving the performance objectives is evident.

  4. Testing and integrating the laser system of ARGOS: the ground layer adaptive optics for LBT

    NASA Astrophysics Data System (ADS)

    Loose, C.; Rabien, S.; Barl, L.; Borelli, J.; Deysenroth, M.; Gaessler, W.; Gemperlein, H.; Honsberg, M.; Kulas, M.; Lederer, R.; Raab, W.; Rahmer, G.; Ziegleder, J.

    2012-07-01

    The Laser Guide Star facility ARGOS will provide Ground Layer Adaptive Optics to the Large Binocular Telescope (LBT). The system operates three pulsed laser beacons above each of the two primary mirrors, which are Rayleigh scattered in 12km height. This enables correction over a wide field of view, using the adaptive secondary mirror of the LBT. The ARGOS laser system is designed around commercially available, pulsed Nd:YAG lasers working at 532 nm. In preparation for a successful commissioning, it is important to ascertain that the specifications are met for every component of the laser system. The testing of assembled, optical subsystems is likewise necessary. In particular it is required to confirm a high output power, beam quality and pulse stability of the beacons. In a second step, the integrated laser system along with its electronic cabinets are installed on a telescope simulator. This unit is capable of carrying the whole assembly and can be tilted to imitate working conditions at the LBT. It allows alignment and functionality testing of the entire system, ensuring that flexure compensation and system diagnosis work properly in different orientations.

  5. Adaptive Management Plan for Sensitive Plant Species on the Nevada Test Site

    SciTech Connect

    C. A. Wills

    2001-03-01

    The Nevada Test Site supports numerous plant species considered sensitive because of their past or present status under the Endangered Species Act and with federal and state agencies. In 1998, the U.S. Department of Energy, Nevada Operation Office (DOE/NV) prepared a Resource Management Plan which commits to protects and conserve these sensitive plant species and to minimize accumulative impacts to them. This document presents the procedures of a long-term adaptive management plan which is meant to ensure that these goals are met. It identifies the parameters that are measured for all sensitive plant populations during long-term monitoring and the adaptive management actions which may be taken if significant threats to these populations are detected. This plan does not, however, identify the current list of sensitive plant species know to occur on the Nevada Test Site. The current species list and progress on their monitoring is reported annually by DOE/NV in the Resource Management Plan.

  6. Key innovation or adaptive change? A test of leaf traits using Triodiinae in Australia.

    PubMed

    Toon, A; Crisp, M D; Gamage, H; Mant, J; Morris, D C; Schmidt, S; Cook, L G

    2015-07-28

    The evolution of novel traits ("key innovations") allows some lineages to move into new environments or adapt to changing climates, whereas other lineages may track suitable habitat or go extinct. We test whether, and how, trait shifts are linked to environmental change using Triodiinae, C4 grasses that form the dominant understory over about 30% of Australia. Using phylogenetic and relaxed molecular clock estimates, we assess the Australian biogeographic origins of Triodiinae and reconstruct the evolution of stomatal and vascular bundle positioning. Triodiinae diversified from the mid-Miocene, coincident with the aridification of Australia. Subsequent niche shifts have been mostly from the Eremaean biome to the savannah, coincident with the expansion of the latter. Biome shifts are correlated with changes in leaf anatomy and radiations within Triodiinae are largely regional. Symplectrodia and Monodia are nested within Triodia. Rather than enabling biome shifts, convergent changes in leaf anatomy have probably occurred after taxa moved into the savannah biome-they are likely to have been subsequent adaptions rather than key innovations. Our study highlights the importance of testing the timing and origin of traits assumed to be phenotypic innovations that enabled ecological shifts.

  7. Design, fabrication, and testing of SMA-enabled adaptive chevrons for jet noise reduction

    NASA Astrophysics Data System (ADS)

    Turner, Travis L.; Buehrle, Ralph D.; Cano, Roberto J.; Fleming, Gary A.

    2004-07-01

    This study presents the status and results from an effort to design, fabricate, and test an adaptive jet engine chevron concept based upon embedding shape memory alloy (SMA) actuators in a composite laminate, termed a SMA hybrid composite (SMAHC). The approach for fabricating the adaptive SMAHC chevrons involves embedding prestrained Nitinol actuators on one side of the mid-plane of the composite laminate such that thermal excitation generates a thermal moment and deflects the structure. A glass-epoxy pre-preg/Nitinol ribbon material system and a vacuum hot press consolidation approach are employed. A versatile test system for control and measurement of the chevron deflection performance is described. Projection moire interferometry (PMI) is used for global deformation measurement and infrared (IR) thermography is used for 2-D temperature measurement and feedback control. A recently commercialized constitutive model for SMA and SMAHC materials is used in the finite element code ABAQUS to perform nonlinear static analysis of the chevron prototypes. Excellent agreement is achieved between the predicted and measured chevron deflection performance, thereby validating the design tool. Although the performance results presented in this paper fall short of the requirement, the concept is proven and an approach for achieving the performance objectives is evident.

  8. Key innovation or adaptive change? A test of leaf traits using Triodiinae in Australia

    PubMed Central

    Toon, A.; Crisp, M. D.; Gamage, H.; Mant, J.; Morris, D. C.; Schmidt, S.; Cook, L. G.

    2015-01-01

    The evolution of novel traits (“key innovations”) allows some lineages to move into new environments or adapt to changing climates, whereas other lineages may track suitable habitat or go extinct. We test whether, and how, trait shifts are linked to environmental change using Triodiinae, C4 grasses that form the dominant understory over about 30% of Australia. Using phylogenetic and relaxed molecular clock estimates, we assess the Australian biogeographic origins of Triodiinae and reconstruct the evolution of stomatal and vascular bundle positioning. Triodiinae diversified from the mid-Miocene, coincident with the aridification of Australia. Subsequent niche shifts have been mostly from the Eremaean biome to the savannah, coincident with the expansion of the latter. Biome shifts are correlated with changes in leaf anatomy and radiations within Triodiinae are largely regional. Symplectrodia and Monodia are nested within Triodia. Rather than enabling biome shifts, convergent changes in leaf anatomy have probably occurred after taxa moved into the savannah biome—they are likely to have been subsequent adaptions rather than key innovations. Our study highlights the importance of testing the timing and origin of traits assumed to be phenotypic innovations that enabled ecological shifts. PMID:26215163

  9. Parasitic infections of domestic cats, Felis catus, in western Hungary.

    PubMed

    Capári, B; Hamel, D; Visser, M; Winter, R; Pfister, K; Rehbein, S

    2013-02-18

    During 2011, faeces from 235 owned domestic cats from a rural area in western Hungary were examined using standard coproscopical techniques. The overall prevalence of cats with endoparasites was 39.6% (95% CI 33.3-46.1). The most frequently identified faecal forms were those of ascarids (Toxocara, 17.4%; Toxascaris 7.2%), followed by those of Aelurostrongylus lungworms (14.5%), hookworms (11.1%), taeniid cestodes (4.7%), Cystoisospora coccidians (4.3%), and capillarids (3.8%). Single and multiple infections with up to five parasites concurrently were founded in 24.7% and 14.9% of the cats, respectively. Mixed endoparasite infections were recorded more frequently (p=0.0245) in cats greater than one year old compared to younger cats. Young cats (≤ 1 year) were parasitized more frequently (p<0.05) with ascarids and Cystoisospora spp. but demonstrated infections of hookworms, lungworms and taeniid cestodes less often than the older cats. Cats with taeniid infection were more likely (p<0.05) to harbour Toxocara, hookworm, Aelurostrongylus, and capillarid infections than cats without taeniid cestodes. Cats of owners who claimed the use of wormers were less frequently helminth-positive compared to cats whose owners did not use anthelmintics (21.2% vs. 44.4%; p=0.001). A subset of 115 faecal samples screened by a coproantigen ELISA revealed Giardia-specific antigen in 37.4% samples. Giardia cysts were found by immunofluorescent staining in 30 of the 43 samples tested positive for Giardia by ELISA. In addition, ectoparasites collected from 82 cats by body search and combing were identified. Fleas (1-30 per cat), biting lice (Felicola subrostratus), and ticks (1-5 per cat) were isolated from 58, 1 and 43 cats, respectively. Ctenocephalides felis was identified on all flea infested cats while single specimens of C. canis and Pulex irritans were recovered from three and two cats, respectively. All but one tick collected were adult Ixodes ricinus; the single other tick was a

  10. [Blood group typing in the cat].

    PubMed

    Haarer, M; Grünbaum, E G

    1993-08-01

    Blood group serological diagnosis in cats is clinically relevant for the prophylaxis of blood group incompatibility reactions. In permanent blood donors, cats used for breeding and recipients with a history of prior blood transfusions, testing should consist of blood typing and antibody detection. As test sera and test cells are not commercially available and since parallel tests for various antibody qualities are necessary, they are usually performed in specialized laboratories. Incompatibility testing has a practical clinical relevance in finding a serological diagnosis before each blood transfusion and in cases of kitten mortality. In emergency situations, cross matching can be performed on slides as a screening test. Negative slide test results then should be verified using the more sensitive test tube or microtiter plate tests.

  11. Functional Task Test: 3. Skeletal Muscle Performance Adaptations to Space Flight

    NASA Technical Reports Server (NTRS)

    Ryder, Jeffrey W.; Wickwire, P. J.; Buxton, R. E.; Bloomberg, J. J.; Ploutz-Snyder, L.

    2011-01-01

    The functional task test is a multi-disciplinary study investigating how space-flight induced changes to physiological systems impacts functional task performance. Impairment of neuromuscular function would be expected to negatively affect functional performance of crewmembers following exposure to microgravity. This presentation reports the results for muscle performance testing in crewmembers. Functional task performance will be presented in the abstract "Functional Task Test 1: sensory motor adaptations associated with postflight alternations in astronaut functional task performance." METHODS: Muscle performance measures were obtained in crewmembers before and after short-duration space flight aboard the Space Shuttle and long-duration International Space Station (ISS) missions. The battery of muscle performance tests included leg press and bench press measures of isometric force, isotonic power and total work. Knee extension was used for the measurement of central activation and maximal isometric force. Upper and lower body force steadiness control were measured on the bench press and knee extension machine, respectively. Tests were implemented 60 and 30 days before launch, on landing day (Shuttle crew only), and 6, 10 and 30 days after landing. Seven Space Shuttle crew and four ISS crew have completed the muscle performance testing to date. RESULTS: Preliminary results for Space Shuttle crew reveal significant reductions in the leg press performance metrics of maximal isometric force, power and total work on R+0 (p<0.05). Bench press total work was also significantly impaired, although maximal isometric force and power were not significantly affected. No changes were noted for measurements of central activation or force steadiness. Results for ISS crew were not analyzed due to the current small sample size. DISCUSSION: Significant reductions in lower body muscle performance metrics were observed in returning Shuttle crew and these adaptations are likely

  12. Cats protecting birds revisited.

    PubMed

    Fan, Meng; Kuang, Yang; Feng, Zhilan

    2005-09-01

    In this paper, we revisit the dynamical interaction among prey (bird), mesopredator (rat), and superpredator (cat) discussed in [Courchamp, F., Langlais, M., Sugihara, G., 1999. Cats protecting birds: modelling the mesopredator release effect. Journal of Animal Ecology 68, 282-292]. First, we develop a prey-mesopredator-superpredator (i.e., bird-rat-cat, briefly, BRC) model, where the predator's functional responses are derived based on the classical Holling's time budget arguments. Our BRC model overcomes several model construction problems in Courchamp et al. (1999), and admits richer, reasonable and realistic dynamics. We explore the possible control strategies to save or restore the bird by controlling or eliminating the rat or the cat when the bird is endangered. We establish the existence of two types of mesopredator release phenomena: severe mesopredator release, where once superpredators are suppressed, a burst of mesopredators follows which leads their shared prey to extinction; and mild mesopredator release, where the mesopredator release could assert more negative impact on the endemic prey but does not lead the endemic prey to extinction. A sharp sufficient criterion is established for the occurrence of severe mesopredator release. We also show that, in a prey-mesopredator-superpredator trophic food web, eradication of introduced superpredators such as feral domestic cats in the BRC model, is not always the best solution to protect endemic insular prey. The presence of a superpredator may have a beneficial effect in such systems.

  13. The Feline Mystique: Dispelling the Myth of the Independent Cat.

    ERIC Educational Resources Information Center

    Soltow, Willow

    1984-01-01

    Describes learning activities about cats for primary and intermediate grades. Primary grade activity subjects include cat behavior, needs, breeds, storybook cats, and celestial cats. Intermediate grade activity subjects include cat history, care, language, literary cats, and cats in art. (BC)

  14. Development and Flight Testing of an Adaptive Vehicle Health-Monitoring Architecture

    NASA Technical Reports Server (NTRS)

    Woodard, Stanley E.; Coffey, Neil C.; Gonzalez, Guillermo A.; Taylor, B. Douglas; Brett, Rube R.; Woodman, Keith L.; Weathered, Brenton W.; Rollins, Courtney H.

    2002-01-01

    On going development and testing of an adaptable vehicle health-monitoring architecture is presented. The architecture is being developed for a fleet of vehicles. It has three operational levels: one or more remote data acquisition units located throughout the vehicle; a command and control unit located within the vehicle, and, a terminal collection unit to collect analysis results from all vehicles. Each level is capable of performing autonomous analysis with a trained expert system. The expert system is parameterized, which makes it adaptable to be trained to both a user's subject reasoning and existing quantitative analytic tools. Communication between all levels is done with wireless radio frequency interfaces. The remote data acquisition unit has an eight channel programmable digital interface that allows the user discretion for choosing type of sensors; number of sensors, sensor sampling rate and sampling duration for each sensor. The architecture provides framework for a tributary analysis. All measurements at the lowest operational level are reduced to provide analysis results necessary to gauge changes from established baselines. These are then collected at the next level to identify any global trends or common features from the prior level. This process is repeated until the results are reduced at the highest operational level. In the framework, only analysis results are forwarded to the next level to reduce telemetry congestion. The system's remote data acquisition hardware and non-analysis software have been flight tested on the NASA Langley B757's main landing gear. The flight tests were performed to validate the following: the wireless radio frequency communication capabilities of the system, the hardware design, command and control; software operation and, data acquisition, storage and retrieval.

  15. Managing Depression Among Homeless Mothers: Pilot Testing an Adapted Collaborative Care Intervention

    PubMed Central

    Weinreb, Linda; Upshur, Carole C.; Fletcher-Blake, Debbian; Reed, George; Frisard, Christine

    2016-01-01

    Objective Although depression is common among homeless mothers, little progress has been made in testing treatment strategies for this group. We describe pilot test results of an adapted collaborative care model for homeless mothers with depression. Method We conducted a pilot intervention study of mothers screening positive for depression in 2 randomly selected shelter-based primary care clinics in New York over 18 months in 2010–2012. Study participants completed a psychosocial, health, and mental health assessment at baseline, 3 months, and 6 months. Results One-third of women screened positive for depression (123 of 328 women). Sixty-seven women (63.2% of the eligible sample) enrolled in the intervention. At 6 months, compared to usual-care women, intervention group women were more likely to be receiving depression treatment (40.0% vs 5.9%, P = .01) and antidepressant medication (73.3% vs 5.9%, P = .001, respectively) and had more primary care physician and care manager visits at both 3 months (74.3% vs 53.3%, P = .009 and 91.4% vs 26.7%, P < .001, respectively) and 6 months (46.7% vs 23.5%, P = .003 and 70% vs 17.7%, P = .001, respectively). More women in the intervention group compared to usual-care women reported ≥ 50% improvement in depression symptoms at 6 months (30% vs 5.9%, P = .07). Conclusions This pilot study found that implementing an adapted collaborative care intervention was feasible in a shelter-based primary care clinic and had promising results that require further testing. Trial Registration ClinicalTrials.gov identifier: NCT02723058 PMID:27486545

  16. Spermatozoa isolated from cat testes retain their structural integrity as well as a developmental potential after refrigeration for up to 7 days.

    PubMed

    Buarpung, Sirirak; Tharasanit, Theerawat; Thongkittidilok, Chommanart; Comizzoli, Pierre; Techakumphu, Mongkol

    2015-10-01

    The objective of this study was to compare the efficiency of preservation media for isolated feline testicular spermatozoa as well as the concentrations of bovine serum albumin (BSA) on: (1) the membrane (sperm membrane integrity (SMI)) and DNA integrity of spermatozoa; and (2) the developmental potential of spermatozoa after intracytoplasmic sperm injection (ICSI). Isolated cat spermatozoa were stored in HEPES-M199 medium (HM) or Dulbecco's phosphate-buffered saline (DPBS) at 4°C for up to 7 days. Results indicated that HM maintained a better SMI than DPBS throughout the storage periods (P > 0.05). When spermatozoa were stored in HM supplemented with BSA at different concentrations (4, 8 or 16 mg/ml), SMI obtained from HM containing 8 and 16 mg/ml BSA was higher than with 4 mg/ml BSA (P 0.05). In summary, cat spermatozoa immediately isolated from testicular tissue can be stored as a suspension in basic buffered medium at 4°C for up to 7 days. BSA supplementation into the medium improves membrane integrity of the spermatozoa during cold storage. Testicular spermatozoa stored in HM containing 16 mg/ml BSA retained full in vitro developmental potential after ICSI, similar to that of fresh controls even though DNA integrity had slightly declined.

  17. An Adaptive Association Test for Multiple Phenotypes with GWAS Summary Statistics.

    PubMed

    Kim, Junghi; Bai, Yun; Pan, Wei

    2015-12-01

    We study the problem of testing for single marker-multiple phenotype associations based on genome-wide association study (GWAS) summary statistics without access to individual-level genotype and phenotype data. For most published GWASs, because obtaining summary data is substantially easier than accessing individual-level phenotype and genotype data, while often multiple correlated traits have been collected, the problem studied here has become increasingly important. We propose a powerful adaptive test and compare its performance with some existing tests. We illustrate its applications to analyses of a meta-analyzed GWAS dataset with three blood lipid traits and another with sex-stratified anthropometric traits, and further demonstrate its potential power gain over some existing methods through realistic simulation studies. We start from the situation with only one set of (possibly meta-analyzed) genome-wide summary statistics, then extend the method to meta-analysis of multiple sets of genome-wide summary statistics, each from one GWAS. We expect the proposed test to be useful in practice as more powerful than or complementary to existing methods.

  18. Flight test results of the fuzzy logic adaptive controller-helicopter (FLAC-H)

    NASA Astrophysics Data System (ADS)

    Wade, Robert L.; Walker, Gregory W.

    1996-05-01

    The fuzzy logic adaptive controller for helicopters (FLAC-H) demonstration is a cooperative effort between the US Army Simulation, Training, and Instrumentation Command (STRICOM), the US Army Aviation and Troop Command, and the US Army Missile Command to demonstrate a low-cost drone control system for both full-scale and sub-scale helicopters. FLAC-H was demonstrated on one of STRICOM's fleet of full-scale rotary-winged target drones. FLAC-H exploits fuzzy logic in its flight control system to provide a robust solution to the control of the helicopter's dynamic, nonlinear system. Straight forward, common sense fuzzy rules governing helicopter flight are processed instead of complex mathematical models. This has resulted in a simplified solution to the complexities of helicopter flight. Incorporation of fuzzy logic reduced the cost of development and should also reduce the cost of maintenance of the system. An adaptive algorithm allows the FLAC-H to 'learn' how to fly the helicopter, enabling the control system to adjust to varying helicopter configurations. The adaptive algorithm, based on genetic algorithms, alters the fuzzy rules and their related sets to improve the performance characteristics of the system. This learning allows FLAC-H to automatically be integrated into a new airframe, reducing the development costs associated with altering a control system for a new or heavily modified aircraft. Successful flight tests of the FLAC-H on a UH-1H target drone were completed in September 1994 at the White Sands Missile Range in New Mexico. This paper discuses the objective of the system, its design, and performance.

  19. SEROPREVALENCE OF TOXOPLASMA GONDII ANTIBODIES IN CATS FROM PENNSLYVANIA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The prevalence of antibodies to Toxoplasma gondii was determined in sera from 122 domestic cats from Bensalem, Pennsylvania. Using a modified agglutination test, antibodies to this parasite were found in 25 (20.4%) of the 122 cats with titers of 1:25 in 1, 1:50 in 4, 1:100 in 6, 1:200 in 3, 1:400...

  20. Local Dependence in an Operational CAT: Diagnosis and Implications

    ERIC Educational Resources Information Center

    Pommerich, Mary; Segall, Daniel O.

    2008-01-01

    The accuracy of CAT scores can be negatively affected by local dependence if the CAT utilizes parameters that are misspecified due to the presence of local dependence and/or fails to control for local dependence in responses during the administration stage. This article evaluates the existence and effect of local dependence in a test of…

  1. ADAPTATION OF CRACK GROWTH DETECTION TECHNIQUES TO US MATERIAL TEST REACTORS

    SciTech Connect

    A. Joseph Palmer; Sebastien P. Teysseyre; Kurt L. Davis; Gordon Kohse; Yakov Ostrovsky; David M. Carpenter; Joy L. Rempe

    2015-04-01

    A key component in evaluating the ability of Light Water Reactors to operate beyond 60 years is characterizing the degradation of materials exposed to radiation and various water chemistries. Of particular concern is the response of reactor materials to Irradiation Assisted Stress Corrosion Cracking (IASCC). Some test reactors outside the United States, such as the Halden Boiling Water Reactor (HBWR), have developed techniques to measure crack growth propagation during irradiation. The basic approach is to use a custom-designed compact loading mechanism to stress the specimen during irradiation, while the crack in the specimen is monitored in-situ using the Direct Current Potential Drop (DCPD) method. In 2012 the US Department of Energy commissioned the Idaho National Laboratory and the MIT Nuclear Reactor Laboratory (MIT NRL) to take the basic concepts developed at the HBWR and adapt them to a test rig capable of conducting in-pile IASCC tests in US Material Test Reactors. The first two and half years of the project consisted of designing and testing the loader mechanism, testing individual components of the in-pile rig and electronic support equipment, and autoclave testing of the rig design prior to insertion in the MIT Reactor. The load was applied to the specimen by means of a scissor like mechanism, actuated by a miniature metal bellows driven by pneumatic pressure and sized to fit within the small in-core irradiation volume. In addition to the loader design, technical challenges included developing robust connections to the specimen for the applied current and voltage measurements, appropriate ceramic insulating materials that can endure the LWR environment, dealing with the high electromagnetic noise environment of a reactor core at full power, and accommodating material property changes in the specimen, due primarily to fast neutron damage, which change the specimen resistance without additional crack growth. The project culminated with an in

  2. Environmentally-controlled Microtensile Testing of Mechanically-adaptive Polymer Nanocomposites for ex vivo Characterization

    PubMed Central

    Hess, Allison E.; Potter, Kelsey A.; Tyler, Dustin J.; Zorman, Christian A.; Capadona, Jeffrey R.

    2013-01-01

    Implantable microdevices are gaining significant attention for several biomedical applications1-4. Such devices have been made from a range of materials, each offering its own advantages and shortcomings5,6. Most prominently, due to the microscale device dimensions, a high modulus is required to facilitate implantation into living tissue. Conversely, the stiffness of the device should match the surrounding tissue to minimize induced local strain7-9. Therefore, we recently developed a new class of bio-inspired materials to meet these requirements by responding to environmental stimuli with a change in mechanical properties10-14. Specifically, our poly(vinyl acetate)-based nanocomposite (PVAc-NC) displays a reduction in stiffness when exposed to water and elevated temperatures (e.g. body temperature). Unfortunately, few methods exist to quantify the stiffness of materials in vivo15, and mechanical testing outside of the physiological environment often requires large samples inappropriate for implantation. Further, stimuli-responsive materials may quickly recover their initial stiffness after explantation. Therefore, we have developed a method by which the mechanical properties of implanted microsamples can be measured ex vivo, with simulated physiological conditions maintained using moisture and temperature control13,16,17. To this end, a custom microtensile tester was designed to accommodate microscale samples13,17 with widely-varying Young's moduli (range of 10 MPa to 5 GPa). As our interests are in the application of PVAc-NC as a biologically-adaptable neural probe substrate, a tool capable of mechanical characterization of samples at the microscale was necessary. This tool was adapted to provide humidity and temperature control, which minimized sample drying and cooling17. As a result, the mechanical characteristics of the explanted sample closely reflect those of the sample just prior to explantation. The overall goal of this method is to quantitatively assess

  3. THE TOXOPLASMA GONDII OOCYST FROM CAT FECES

    PubMed Central

    Dubey, J. P.; Miller, Nancy L.; Frenkel, J. K.

    1970-01-01

    Coccidian oocysts resembling those of Isospora bigemina were excreted by cats fed Toxoplasma. In order to identify these oocysts with Toxoplasma infectivity a number of critical comparisons were made. The appearance of oocysts and Toxoplasma infectivity was simultaneous in the feces of 23 of 24 adult cats, 3–5 days after feeding of Toxoplasma cysts; in the feces of 4 out of 9 cats, 7–10 days after feeding of trophozoites; and in 8 out of 17 cats, 20–24 days after feeding of cat feces containing oocysts. Oocysts and infectivity were present in similar numbers, and they disappeared simultaneously from the feces of cats. Oocysts and infectivity were also observed simultaneously in the feces of 9 kittens, 1–2 days old, fed Toxoplasma cysts. Oocysts could not be separated from infectivity by filtration, by continuous particle electrophoresis, or by density gradient centrifugation. Excystation of oocysts was followed by an increase in titer of Toxoplasma infectivity. Unsporulated oocysts in fresh cat feces were noninfectious to mice, but oocyst sporulation was associated quantitatively with the development of infectivity at different temperatures and conditions of oxygenation. Maximum oocyst sporulation at 48 hr correlated with the development of maximum Toxoplasma infectivity. 1 and 2% sulfuric acid, and 2.5% potassium dichromate were found to be the best preservatives for sporulation of oocysts and for the development of Toxoplasma infectivity. Low sporulation rates in 0.1% formalin, 20% ethanol, and in water were associated with low infectivity in these reagents. Neither Toxoplasma infectivity nor oocysts developed in 0.3% formalin, 1% ammonium hydroxide, or 1% iodine in 20% ethanol. Oocysts, sporocysts, and sporozoites were stained specifically with Toxoplasma antibody in the indirect fluorescent antibody test. Typical coccidian stages, schizonts, and male and female gametocytes were found in the epithelium of the small intestine of kittens fed Toxoplasma

  4. The Toxoplasma gondii oocyst from cat feces.

    PubMed

    Dubey, J P; Miller, N L; Frenkel, J K

    1970-10-01

    Coccidian oocysts resembling those of Isospora bigemina were excreted by cats fed Toxoplasma. In order to identify these oocysts with Toxoplasma infectivity a number of critical comparisons were made. The appearance of oocysts and Toxoplasma infectivity was simultaneous in the feces of 23 of 24 adult cats, 3-5 days after feeding of Toxoplasma cysts; in the feces of 4 out of 9 cats, 7-10 days after feeding of trophozoites; and in 8 out of 17 cats, 20-24 days after feeding of cat feces containing oocysts. Oocysts and infectivity were present in similar numbers, and they disappeared simultaneously from the feces of cats. Oocysts and infectivity were also observed simultaneously in the feces of 9 kittens, 1-2 days old, fed Toxoplasma cysts. Oocysts could not be separated from infectivity by filtration, by continuous particle electrophoresis, or by density gradient centrifugation. Excystation of oocysts was followed by an increase in titer of Toxoplasma infectivity. Unsporulated oocysts in fresh cat feces were noninfectious to mice, but oocyst sporulation was associated quantitatively with the development of infectivity at different temperatures and conditions of oxygenation. Maximum oocyst sporulation at 48 hr correlated with the development of maximum Toxoplasma infectivity. 1 and 2% sulfuric acid, and 2.5% potassium dichromate were found to be the best preservatives for sporulation of oocysts and for the development of Toxoplasma infectivity. Low sporulation rates in 0.1% formalin, 20% ethanol, and in water were associated with low infectivity in these reagents. Neither Toxoplasma infectivity nor oocysts developed in 0.3% formalin, 1% ammonium hydroxide, or 1% iodine in 20% ethanol. Oocysts, sporocysts, and sporozoites were stained specifically with Toxoplasma antibody in the indirect fluorescent antibody test. Typical coccidian stages, schizonts, and male and female gametocytes were found in the epithelium of the small intestine of kittens fed Toxoplasma cysts. The

  5. Cat sensitivity: 7-yr audit in children attending a paediatric allergy clinic in North Italy.

    PubMed

    Pescollderungg, L; Pietrobelli, A; Boner, A L

    2000-11-01

    Sensitivity to cats and exposure to cat allergen is a common cause of asthma exacerbation in children. To date, there is no data on the prevalence of cat sensitivity in children living in North Italy. Therefore, a 7-yr survey was performed in patients attending an allergy clinic for the first time. Skin prick tests (SPT) for perennial allergens and for pollens relevant to the region were performed in 4,957 children attending the outpatient clinic 1992-1998. A questionnaire on present or past cat ownership was presented to all cat-skin prick test positive children. An evaluation of cat ownership on the general population was made by telephone interview on a random sample of 1,268 families living in the same area. With a 3-mm wheal as a positive cut-off 439 (8.85%) children had a positive SPT to cats. Of these 103 (23.4%) had a cat at home and 336 (76.6%) never had a cat in the house. With a greater positive cut-off(a wheal diameter > or =4 mm) 140 (2.8%) showed a positive SPT to cats of these 35 (25%) had a cat at home and 105 (75%) had only an indirect exposure to the pet. Of the telephone interviewed families; 16% stated they had a cat at home. Cat sensitivity is less prevalent in Italy, in this hospital based population, compared with other European countries and this is in agreement with a lower rate of cat ownership. Cat sensitivity was three times more frequent in children who never had a cat at home, than in children living with cats, when the selected positive cut-off was either a wheal diameter of 3 mm or > or =4 mm. Thus in a population with a low prevalence of cat ownership public exposure seems to be more important than domestic exposure for the development of sensitivity.

  6. Testing Adaptive Hypotheses of Convergence with Functional Landscapes: A Case Study of Bone-Cracking Hypercarnivores

    PubMed Central

    Tseng, Zhijie Jack

    2013-01-01

    Morphological convergence is a well documented phenomenon in mammals, and adaptive explanations are commonly employed to infer similar functions for convergent characteristics. I present a study that adopts aspects of theoretical morphology and engineering optimization to test hypotheses about adaptive convergent evolution. Bone-cracking ecomorphologies in Carnivora were used as a case study. Previous research has shown that skull deepening and widening are major evolutionary patterns in convergent bone-cracking canids and hyaenids. A simple two-dimensional design space, with skull width-to-length and depth-to-length ratios as variables, was used to examine optimized shapes for two functional properties: mechanical advantage (MA) and strain energy (SE). Functionality of theoretical skull shapes was studied using finite element analysis (FEA) and visualized as functional landscapes. The distribution of actual skull shapes in the landscape showed a convergent trend of plesiomorphically low-MA and moderate-SE skulls evolving towards higher-MA and moderate-SE skulls; this is corroborated by FEA of 13 actual specimens. Nevertheless, regions exist in the landscape where high-MA and lower-SE shapes are not represented by existing species; their vacancy is observed even at higher taxonomic levels. Results highlight the interaction of biomechanical and non-biomechanical factors in constraining general skull dimensions to localized functional optima through evolution. PMID:23734244

  7. Comparing Computer-Adaptive and Curriculum-Based Measurement Methods of Assessment

    ERIC Educational Resources Information Center

    Shapiro, Edward S.; Gebhardt, Sarah N.

    2012-01-01

    This article reported the concurrent, predictive, and diagnostic accuracy of a computer-adaptive test (CAT) and curriculum-based measurements (CBM; both computation and concepts/application measures) for universal screening in mathematics among students in first through fourth grade. Correlational analyses indicated moderate to strong…

  8. Who's behind that mask and cape? The Asian leopard cat's Agouti (ASIP) allele likely affects coat colour phenotype in the Bengal cat breed.

    PubMed

    Gershony, L C; Penedo, M C T; Davis, B W; Murphy, W J; Helps, C R; Lyons, L A

    2014-12-01

    Coat colours and patterns are highly variable in cats and are determined mainly by several genes with Mendelian inheritance. A 2-bp deletion in agouti signalling protein (ASIP) is associated with melanism in domestic cats. Bengal cats are hybrids between domestic cats and Asian leopard cats (Prionailurus bengalensis), and the charcoal coat colouration/pattern in Bengals presents as a possible incomplete melanism. The complete coding region of ASIP was directly sequenced in Asian leopard, domestic and Bengal cats. Twenty-seven variants were identified between domestic and leopard cats and were investigated in Bengals and Savannahs, a hybrid with servals (Leptailurus serval). The leopard cat ASIP haplotype was distinguished from domestic cat by four synonymous and four non-synonymous exonic SNPs, as well as 19 intronic variants, including a 42-bp deletion in intron 4. Fifty-six of 64 reported charcoal cats were compound heterozygotes at ASIP, with leopard cat agouti (A(P) (be) ) and domestic cat non-agouti (a) haplotypes. Twenty-four Bengals had an additional unique haplotype (A2) for exon 2 that was not identified in leopard cats, servals or jungle cats (Felis chaus). The compound heterozygote state suggests the leopard cat allele, in combination with the recessive non-agouti allele, influences Bengal markings, producing a darker, yet not completely melanistic coat. This is the first validation of a leopard cat allele segregating in the Bengal breed and likely affecting their overall pelage phenotype. Genetic testing services need to be aware of the possible segregation of wild felid alleles in all assays performed on hybrid cats.

  9. Flight Test Comparison of Different Adaptive Augmentations for Fault Tolerant Control Laws for a Modified F-15 Aircraft

    NASA Technical Reports Server (NTRS)

    Burken, John J.; Hanson, Curtis E.; Lee, James A.; Kaneshige, John T.

    2009-01-01

    This report describes the improvements and enhancements to a neural network based approach for directly adapting to aerodynamic changes resulting from damage or failures. This research is a follow-on effort to flight tests performed on the NASA F-15 aircraft as part of the Intelligent Flight Control System research effort. Previous flight test results demonstrated the potential for performance improvement under destabilizing damage conditions. Little or no improvement was provided under simulated control surface failures, however, and the adaptive system was prone to pilot-induced oscillations. An improved controller was designed to reduce the occurrence of pilot-induced oscillations and increase robustness to failures in general. This report presents an analysis of the neural networks used in the previous flight test, the improved adaptive controller, and the baseline case with no adaptation. Flight test results demonstrate significant improvement in performance by using the new adaptive controller compared with the previous adaptive system and the baseline system for control surface failures.

  10. L1 Adaptive Control Law for Flexible Space Launch Vehicle and Proposed Plan for Flight Test Validation

    NASA Technical Reports Server (NTRS)

    Kharisov, Evgeny; Gregory, Irene M.; Cao, Chengyu; Hovakimyan, Naira

    2008-01-01

    This paper explores application of the L1 adaptive control architecture to a generic flexible Crew Launch Vehicle (CLV). Adaptive control has the potential to improve performance and enhance safety of space vehicles that often operate in very unforgiving and occasionally highly uncertain environments. NASA s development of the next generation space launch vehicles presents an opportunity for adaptive control to contribute to improved performance of this statically unstable vehicle with low damping and low bending frequency flexible dynamics. In this paper, we consider the L1 adaptive output feedback controller to control the low frequency structural modes and propose steps to validate the adaptive controller performance utilizing one of the experimental test flights for the CLV Ares-I Program.

  11. Usability Testing and Adaptation of the Pediatric Cardiovascular Risk Reduction Clinical Decision Support Tool

    PubMed Central

    Furberg, Robert D; Bagwell, Jacqueline E; LaBresh, Kenneth A

    2016-01-01

    Background Cardiovascular disease (CVD) is 1 of the leading causes of death, years of life lost, and disability-adjusted years of life lost worldwide. CVD prevention for children and teens is needed, as CVD risk factors and behaviors beginning in youth contribute to CVD development. In 2012, the National Heart, Lung, and Blood Institute released their “Integrated Guidelines for Cardiovascular Health and Risk Reduction in Children and Adolescents” for clinicians, describing CVD risk factors they should address with patients at primary care preventative visits. However, uptake of new guidelines is slow. Clinical decision support (CDS) tools can improve guideline uptake. In this paper, we describe our process of testing and adapting a CDS tool to help clinicians evaluate patient risk, recommend behaviors to prevent development of risk, and complete complex calculations to determine appropriate interventions as recommended by the guidelines, using a user-centered design approach. Objective The objective of the study was to assess the usability of a pediatric CVD risk factor tool by clinicians. Methods The tool was tested using one-on-one in-person testing and a “think aloud” approach with 5 clinicians and by using the tool in clinical practice along with formal usability metrics with 14 pediatricians. Thematic analysis of the data from the in-person testing and clinical practice testing identified suggestions for change in 3 major areas: user experience, content refinement, and technical deployment. Descriptive statistical techniques were employed to summarize users’ overall experience with the tool. Results Data from testers showed that general reactions toward the CDS tool were positive. Clinical practice testers suggested revisions to make the application more user-friendly, especially for clinicians using the application on the iPhone, and called for refining recommendations to be more succinct and better tailored to the patient. Tester feedback was

  12. Validation of a microsatellite panel for parentage testing of locally adapted and commercial goats in Brazil.

    PubMed

    da Silva, Elizabete Cristina; McManus, Concepta Margaret; de Paiva Guimarães, Maria Pia Souza Lima Mattos; Gouveia, Aurora M G; Facó, Olivardo; Pimentel, Daniel M; Caetano, Alexandre Rodrigues; Paiva, Samuel Rezende

    2014-03-01

    Brazilian goats are generally kept in small herds and extensive rearing systems, mainly in the northeastern region of the country. Despite production improvement in recent years, the lack of pedigree control has affected genetic progress. This study aimed to validate a panel of 16 microsatellites for parentage testing in locally adapted and commercial goats breeds raised in Brazil, as well as to compare its efficiency with the panel recommended by the Brazilian Ministry of Agriculture, Livestock and Supplies (MAPA) in 2004. The number of alleles and expected heterozygosity (He) per marker ranged from four to 18, and from 0.051 to 0.831, respectively. Using all markers, 100% of parentage cases of the validation dataset were resolved with a strict confidence level of 95%. The 16 microsatellites panel showed adequate exclusion power (99.99%) and identity accuracy (99.99%). Suggestions for improvement of the marker panel endorsed by MAPA are provided.

  13. Validation of a microsatellite panel for parentage testing of locally adapted and commercial goats in Brazil

    PubMed Central

    da Silva, Elizabete Cristina; McManus, Concepta Margaret; de Paiva Guimarães, Maria Pia Souza Lima Mattos; Gouveia, Aurora M.G.; Facó, Olivardo; Pimentel, Daniel M.; Caetano, Alexandre Rodrigues; Paiva, Samuel Rezende

    2014-01-01

    Brazilian goats are generally kept in small herds and extensive rearing systems, mainly in the northeastern region of the country. Despite production improvement in recent years, the lack of pedigree control has affected genetic progress. This study aimed to validate a panel of 16 microsatellites for parentage testing in locally adapted and commercial goats breeds raised in Brazil, as well as to compare its efficiency with the panel recommended by the Brazilian Ministry of Agriculture, Livestock and Supplies (MAPA) in 2004. The number of alleles and expected heterozygosity (He) per marker ranged from four to 18, and from 0.051 to 0.831, respectively. Using all markers, 100% of parentage cases of the validation dataset were resolved with a strict confidence level of 95%. The 16 microsatellites panel showed adequate exclusion power (99.99%) and identity accuracy (99.99%). Suggestions for improvement of the marker panel endorsed by MAPA are provided. PMID:24688291

  14. Adaptive support for aircraft panel testing: New method and its experimental verification on a beam structure

    NASA Astrophysics Data System (ADS)

    Sachau, Delf; Baschke, Manuel

    2017-04-01

    Acoustic transmissibility of aircraft panels is measured in full-scale test rigs. The panels are supported at their frames. These boundary conditions do not take into account the dynamic influence of the fuselage, which is significant in the frequency range below 300 Hz. This paper introduces a new adaptive boundary system (ABS). It combines accelerometers and electrodynamic shakers with real-time signal processing. The ABS considers the dynamic effect of the fuselage on the panel. The frames are dominating the dynamic behaviour of a fuselage in the low-frequency range. Therefore, the new method is applied to a beam representing a frame of the aircraft structure. The experimental results are evaluated and the precision of the ABS is discussed. The theoretical apparent mass representing the cut-off part of a frame is calculated and compared with the apparent mass, as provided by the ABS. It is explained how the experimental set-up limits the precision of the ABS.

  15. The focal plane adaptive optics test box of the Observatoire du Mont-Mégantic

    NASA Astrophysics Data System (ADS)

    Deschênes, William; Brousseau, Denis; Lavigne, Jean-Francois; Thibault, Simon; Véran, Jean-Pierre

    2014-08-01

    With the upcoming construction of Extremely Large Telescopes, several existing technologies are being pushed beyond their performance limit and it becomes essential to develop and evaluate new alternatives. The "Observatoire du Mont Mégantic" (OMM) hosts a telescope having a 1.6-meter diameter primary. The OMM telescope is known to be an excellent location to develop and test precursor instruments which are then upscaled to larger telescopes (ex. SPIOMM which led to SITELLE at the CFHT). We present a specifically designed focal plane box for the OMM which will allow to evaluate, directly on-sky, the performance of a number of next generation adaptive optics related technologies The system will able us to compare the performance of several new wavefront sensors in contrast with the current standard, the Shack-Hartman wavefront sensor.

  16. Adaptability test of lettuce to soil-like substrate in bioregenerative life support system

    NASA Astrophysics Data System (ADS)

    Min, Yan; Liu, Professor Hong; Wenting, Fu

    Plant cultivation using soil-like substrate (SLS) is considered to be a feasible option for building up matter for biological turnover in bioregenerative life support system (BLSS) by many researchers. The characteristics of SLS are different from those of true soil therefore it is very important to study the adaptability of candidate crop to SLS in BLSS. This study was carried out in three successive steps to test the adaptability of lettuce (Lactuca sativa L.) to rice straw SLS in BLSS of China. First, six Chinese specific lettuce cultivars which were selected for Chinese advanced life support system were planted into the same rice straw SLS, which was to determine the more suitable plant cultivar to do the next experiment. The results showed that Sharp Leaf lettuce and Red lettuce were more suitable for SLS than other cultivars. Second, the possibility of increasing the crop yield on the SLS was conducted by changing the soil depth and plant density. Sharp Leaf lettuce and Red lettuce were used into this experiment in order to obtain the highest yield under the smallest soil volume and weight at the same light intensity. Crop edible biomass, crop nutrition content and photosynthetic characteristics were estimated during the experiment. Red lettuce obtained higher biomass and photosynthesis capacity. Lastly, the stability of planting system of lettuce and SLS was evaluated in the closed controlled system. Red lettuce would be the test plant. In this experiment different age lettuce groups would be planted together and gas exchange would be measured. In all of these experiments soil physical and chemical characteristics were also be measured which will be the basal data for further research.

  17. Niche evolution and adaptive radiation: Testing the order of trait divergence

    USGS Publications Warehouse

    Ackerly, D.D.; Schwilk, D.W.; Webb, C.O.

    2006-01-01

    In the course of an adaptive radiation, the evolution of niche parameters is of particular interest for understanding modes of speciation and the consequences for coexistence of related species within communities. We pose a general question: In the course of an evolutionary radiation, do traits related to within-community niche differences (?? niche) evolve before or after differentiation of macrohabitat affinity or climatic tolerances (?? niche)? Here we introduce a new test to address this question, based on a modification of the method of independent contrasts. The divergence order test (DOT) is based on the average age of the nodes on a tree, weighted by the absolute magnitude of the contrast at each node for a particular trait. The comparison of these weighted averages reveals whether large divergences for one trait have occurred earlier or later in the course of diversification, relative to a second trait; significance is determined by bootstrapping from maximum-likelihood ancestral state reconstructions. The method is applied to the evolution of Ceanothus, a woody plant group in California, in which co-occurring species exhibit significant differences in a key leaf trait (specific leaf area) associated with contrasting physiological and life history strategies. Co-occurring species differ more for this trait than expected under a null model of community assembly. This ?? niche difference evolved early in the divergence of two major subclades within Ceanothus, whereas climatic distributions (?? niche traits) diversified later within each of the subclades. However, rapid evolution of climate parameters makes inferences of early divergence events highly uncertain, and differentiation of the ?? niche might have taken place throughout the evolution of the group, without leaving a clear phylogenetic signal. Similar patterns observed in several plant and animal groups suggest that early divergence of ?? niche traits might be a common feature of niche evolution in

  18. Infectious diseases in large-scale cat hoarding investigations.

    PubMed

    Polak, K C; Levy, J K; Crawford, P C; Leutenegger, C M; Moriello, K A

    2014-08-01

    Animal hoarders accumulate animals in over-crowded conditions without adequate nutrition, sanitation, and veterinary care. As a result, animals rescued from hoarding frequently have a variety of medical conditions including respiratory infections, gastrointestinal disease, parasitism, malnutrition, and other evidence of neglect. The purpose of this study was to characterize the infectious diseases carried by clinically affected cats and to determine the prevalence of retroviral infections among cats in large-scale cat hoarding investigations. Records were reviewed retrospectively from four large-scale seizures of cats from failed sanctuaries from November 2009 through March 2012. The number of cats seized in each case ranged from 387 to 697. Cats were screened for feline leukemia virus (FeLV) and feline immunodeficiency virus (FIV) in all four cases and for dermatophytosis in one case. A subset of cats exhibiting signs of upper respiratory disease or diarrhea had been tested for infections by PCR and fecal flotation for treatment planning. Mycoplasma felis (78%), calicivirus (78%), and Streptococcus equi subspecies zooepidemicus (55%) were the most common respiratory infections. Feline enteric coronavirus (88%), Giardia (56%), Clostridium perfringens (49%), and Tritrichomonas foetus (39%) were most common in cats with diarrhea. The seroprevalence of FeLV and FIV were 8% and 8%, respectively. In the one case in which cats with lesions suspicious for dermatophytosis were cultured for Microsporum canis, 69/76 lesional cats were culture-positive; of these, half were believed to be truly infected and half were believed to be fomite carriers. Cats from large-scale hoarding cases had high risk for enteric and respiratory infections, retroviruses, and dermatophytosis. Case responders should be prepared for mass treatment of infectious diseases and should implement protocols to prevent transmission of feline or zoonotic infections during the emergency response and when

  19. Presumptive sialadenosis in a cat.

    PubMed

    Boydell, P; Pike, R; Crossley, D

    2000-12-01

    A cat was presented with signs associated with enlargement of the mandibular salivary glands. Histological findings were normal, consistent with a diagnosis of sialadenosis, and the cat responded to symptomatic treatment with oral phenobarbitone.

  20. Prevalence of mucopolysaccharidosis type VI mutations in Siamese cats.

    PubMed

    Crawley, A C; Muntz, F H; Haskins, M E; Jones, B R; Hopwood, J J

    2003-01-01

    Mucopolysaccharidosis type VI (MPS VI), a lysosomal storage disease, is one of the more prevalent inherited diseases in cats and is commonly found in cats with Siamese ancestry. The prevalence of 2 known MPS VI mutations in cats was investigated in 101 clinically normal Siamese cats, in 2 cats with clinical signs of MPS VI, and in 202 cats from 4 research colonies. The mutation L476P which causes a severe clinical phenotype, was present on both alleles in the known MPS VI cats from Italy and North America and was present in all research colonies that originated from North America. However, LA76P was not detected in the Siamese population screened. In contrast, the mutation D520N, which causes a mild clinical phenotype, was identified in 23 of 202 (11.4%) alleles tested in Siamese cats from 3 continents, 2 of which were homozygous for D520N. Thus, the D520N mutation was widespread, and it is likely that cats inheriting both mutations (LA76P/D520N compound heterozygotes) would be in the general Siamese population, particularly in North America. Practitioners should note the high incidence of degenerative joint disease in these animals.