WorldWideScience

Sample records for model reproduces qualitatively

  1. Reproducibility in Computational Neuroscience Models and Simulations

    Science.gov (United States)

    McDougal, Robert A.; Bulanova, Anna S.; Lytton, William W.

    2016-01-01

    Objective Like all scientific research, computational neuroscience research must be reproducible. Big data science, including simulation research, cannot depend exclusively on journal articles as the method to provide the sharing and transparency required for reproducibility. Methods Ensuring model reproducibility requires the use of multiple standard software practices and tools, including version control, strong commenting and documentation, and code modularity. Results Building on these standard practices, model sharing sites and tools have been developed that fit into several categories: 1. standardized neural simulators, 2. shared computational resources, 3. declarative model descriptors, ontologies and standardized annotations; 4. model sharing repositories and sharing standards. Conclusion A number of complementary innovations have been proposed to enhance sharing, transparency and reproducibility. The individual user can be encouraged to make use of version control, commenting, documentation and modularity in development of models. The community can help by requiring model sharing as a condition of publication and funding. Significance Model management will become increasingly important as multiscale models become larger, more detailed and correspondingly more difficult to manage by any single investigator or single laboratory. Additional big data management complexity will come as the models become more useful in interpreting experiments, thus increasing the need to ensure clear alignment between modeling data, both parameters and results, and experiment. PMID:27046845

  2. A reproducible canine model of esophageal varices.

    Science.gov (United States)

    Jensen, D M; Machicado, G A; Tapia, J I; Kauffman, G; Franco, P; Beilin, D

    1983-03-01

    One of the most promising nonoperative techniques for control of variceal hemorrhage is sclerosis via the fiberoptic endoscope. Many questions remain, however, about sclerosing agents, guidelines for effective use, and limitations of endoscopic techniques. A reproducible large animal model of esophageal varices would facilitate the critical evaluation of techniques for variceal hemostasis or sclerosis. Our purpose was to develop a large animal model of esophageal varices. Studies in pigs and dogs are described which led to the development of a reproducible canine model of esophageal varices. For the final model, mongrel dogs had laparotomy, side-to-side portacaval shunt, inferior vena cava ligation, placement of an ameroid constrictor around the portal vein, and liver biopsy. The mean (+/- SE) pre- and postshunt portal pressure increased significantly from 12 +/- 0.4 to 23 +/- 1 cm saline. Weekly endoscopies were performed to grade the varix size. Two-thirds of animals developed medium or large sized esophageal varices after the first operation. Three to six weeks later, a second laparotomy with complete ligation of the portal vein and liver biopsy were performed in animals with varices (one-third of the animals). All dogs developed esophageal varices and abdominal wall collateral veins of variable size 3-6 wk after the first operation. After the second operation, the varices became larger. Shunting of blood through esophageal varices via splenic and gastric veins was demonstrated by angiography. Sequential liver biopsies were normal. There was no morbidity or mortality. Ascites, encephalopathy, or spontaneous variceal bleeding did not occur. We have documented the lack of size change and the persistence of medium to large esophageal varices and abdominal collateral veins in all animals followed for more than 6 mo. Variceal bleeding could be induced by venipuncture for testing endoscopic hemostatic and sclerosis methods. We suggest other potential uses of this

  3. Modeling reproducibility of porescale multiphase flow experiments

    Science.gov (United States)

    Ling, B.; Tartakovsky, A. M.; Bao, J.; Oostrom, M.; Battiato, I.

    2017-12-01

    Multi-phase flow in porous media is widely encountered in geological systems. Understanding immiscible fluid displacement is crucial for processes including, but not limited to, CO2 sequestration, non-aqueous phase liquid contamination and oil recovery. Microfluidic devices and porescale numerical models are commonly used to study multiphase flow in biological, geological, and engineered porous materials. In this work, we perform a set of drainage and imbibition experiments in six identical microfluidic cells to study the reproducibility of multiphase flow experiments. We observe significant variations in the experimental results, which are smaller during the drainage stage and larger during the imbibition stage. We demonstrate that these variations are due to sub-porescale geometry differences in microcells (because of manufacturing defects) and variations in the boundary condition (i.e.,fluctuations in the injection rate inherent to syringe pumps). Computational simulations are conducted using commercial software STAR-CCM+, both with constant and randomly varying injection rate. Stochastic simulations are able to capture variability in the experiments associated with the varying pump injection rate.

  4. Towards reproducible descriptions of neuronal network models.

    Directory of Open Access Journals (Sweden)

    Eilen Nordlie

    2009-08-01

    Full Text Available Progress in science depends on the effective exchange of ideas among scientists. New ideas can be assessed and criticized in a meaningful manner only if they are formulated precisely. This applies to simulation studies as well as to experiments and theories. But after more than 50 years of neuronal network simulations, we still lack a clear and common understanding of the role of computational models in neuroscience as well as established practices for describing network models in publications. This hinders the critical evaluation of network models as well as their re-use. We analyze here 14 research papers proposing neuronal network models of different complexity and find widely varying approaches to model descriptions, with regard to both the means of description and the ordering and placement of material. We further observe great variation in the graphical representation of networks and the notation used in equations. Based on our observations, we propose a good model description practice, composed of guidelines for the organization of publications, a checklist for model descriptions, templates for tables presenting model structure, and guidelines for diagrams of networks. The main purpose of this good practice is to trigger a debate about the communication of neuronal network models in a manner comprehensible to humans, as opposed to machine-readable model description languages. We believe that the good model description practice proposed here, together with a number of other recent initiatives on data-, model-, and software-sharing, may lead to a deeper and more fruitful exchange of ideas among computational neuroscientists in years to come. We further hope that work on standardized ways of describing--and thinking about--complex neuronal networks will lead the scientific community to a clearer understanding of high-level concepts in network dynamics, and will thus lead to deeper insights into the function of the brain.

  5. Cyberinfrastructure to Support Collaborative and Reproducible Computational Hydrologic Modeling

    Science.gov (United States)

    Goodall, J. L.; Castronova, A. M.; Bandaragoda, C.; Morsy, M. M.; Sadler, J. M.; Essawy, B.; Tarboton, D. G.; Malik, T.; Nijssen, B.; Clark, M. P.; Liu, Y.; Wang, S. W.

    2017-12-01

    Creating cyberinfrastructure to support reproducibility of computational hydrologic models is an important research challenge. Addressing this challenge requires open and reusable code and data with machine and human readable metadata, organized in ways that allow others to replicate results and verify published findings. Specific digital objects that must be tracked for reproducible computational hydrologic modeling include (1) raw initial datasets, (2) data processing scripts used to clean and organize the data, (3) processed model inputs, (4) model results, and (5) the model code with an itemization of all software dependencies and computational requirements. HydroShare is a cyberinfrastructure under active development designed to help users store, share, and publish digital research products in order to improve reproducibility in computational hydrology, with an architecture supporting hydrologic-specific resource metadata. Researchers can upload data required for modeling, add hydrology-specific metadata to these resources, and use the data directly within HydroShare.org for collaborative modeling using tools like CyberGIS, Sciunit-CLI, and JupyterHub that have been integrated with HydroShare to run models using notebooks, Docker containers, and cloud resources. Current research aims to implement the Structure For Unifying Multiple Modeling Alternatives (SUMMA) hydrologic model within HydroShare to support hypothesis-driven hydrologic modeling while also taking advantage of the HydroShare cyberinfrastructure. The goal of this integration is to create the cyberinfrastructure that supports hypothesis-driven model experimentation, education, and training efforts by lowering barriers to entry, reducing the time spent on informatics technology and software development, and supporting collaborative research within and across research groups.

  6. Reproducibility and Transparency in Ocean-Climate Modeling

    Science.gov (United States)

    Hannah, N.; Adcroft, A.; Hallberg, R.; Griffies, S. M.

    2015-12-01

    Reproducibility is a cornerstone of the scientific method. Within geophysical modeling and simulation achieving reproducibility can be difficult, especially given the complexity of numerical codes, enormous and disparate data sets, and variety of supercomputing technology. We have made progress on this problem in the context of a large project - the development of new ocean and sea ice models, MOM6 and SIS2. Here we present useful techniques and experience.We use version control not only for code but the entire experiment working directory, including configuration (run-time parameters, component versions), input data and checksums on experiment output. This allows us to document when the solutions to experiments change, whether due to code updates or changes in input data. To avoid distributing large input datasets we provide the tools for generating these from the sources, rather than provide raw input data.Bugs can be a source of non-determinism and hence irreproducibility, e.g. reading from or branching on uninitialized memory. To expose these we routinely run system tests, using a memory debugger, multiple compilers and different machines. Additional confidence in the code comes from specialised tests, for example automated dimensional analysis and domain transformations. This has entailed adopting a code style where we deliberately restrict what a compiler can do when re-arranging mathematical expressions.In the spirit of open science, all development is in the public domain. This leads to a positive feedback, where increased transparency and reproducibility makes using the model easier for external collaborators, who in turn provide valuable contributions. To facilitate users installing and running the model we provide (version controlled) digital notebooks that illustrate and record analysis of output. This has the dual role of providing a gross, platform-independent, testing capability and a means to documents model output and analysis.

  7. Paleomagnetic analysis of curved thrust belts reproduced by physical models

    Science.gov (United States)

    Costa, Elisabetta; Speranza, Fabio

    2003-12-01

    This paper presents a new methodology for studying the evolution of curved mountain belts by means of paleomagnetic analyses performed on analogue models. Eleven models were designed aimed at reproducing various tectonic settings in thin-skinned tectonics. Our models analyze in particular those features reported in the literature as possible causes for peculiar rotational patterns in the outermost as well as in the more internal fronts. In all the models the sedimentary cover was reproduced by frictional low-cohesion materials (sand and glass micro-beads), which detached either on frictional or on viscous layers. These latter were reproduced in the models by silicone. The sand forming the models has been previously mixed with magnetite-dominated powder. Before deformation, the models were magnetized by means of two permanent magnets generating within each model a quasi-linear magnetic field of intensity variable between 20 and 100 mT. After deformation, the models were cut into closely spaced vertical sections and sampled by means of 1×1-cm Plexiglas cylinders at several locations along curved fronts. Care was taken to collect paleomagnetic samples only within virtually undeformed thrust sheets, avoiding zones affected by pervasive shear. Afterwards, the natural remanent magnetization of these samples was measured, and alternating field demagnetization was used to isolate the principal components. The characteristic components of magnetization isolated were used to estimate the vertical-axis rotations occurring during model deformation. We find that indenters pushing into deforming belts from behind form non-rotational curved outer fronts. The more internal fronts show oroclinal-type rotations of a smaller magnitude than that expected for a perfect orocline. Lateral symmetrical obstacles in the foreland colliding with forward propagating belts produce non-rotational outer curved fronts as well, whereas in between and inside the obstacles a perfect orocline forms

  8. Qualitative and quantitative histopathology in transitional cell carcinomas of the urinary bladder. An international investigation of intra- and interobserver reproducibility

    DEFF Research Database (Denmark)

    Sørensen, Flemming Brandt; Sasaki, M; Fukuzawa, S

    1994-01-01

    of both qualitative and quantitative grading methods. Grading of malignancy was performed by one observer in Japan (using the World Health Organization scheme), and by two observers in Denmark (using the Bergkvist system). A "translation" between the systems, grade for grade, and kappa statistics were...... used in evaluating the reproducibility. Unbiased estimates of nuclear mean volume, nuclear mean profile area, nuclear volume fraction, nuclear profile density index, and mitotic profile density index were obtained twice in 55 of the studied cases by one observer in Japan and one in Denmark, using...... a random, systematic sampling scheme. RESULTS: The results were compared by bivariate correlation analyses and Kendall's tau. The international interobserver reproducibility of qualitative gradings was rather poor (kappa = 0.51), especially for grade 2 tumors (kappa = 0.28). Likewise, the interobserver...

  9. Can global chemistry-climate models reproduce air quality extremes?

    Science.gov (United States)

    Schnell, J.; Prather, M. J.; Holmes, C. D.

    2013-12-01

    We identify and characterize extreme ozone pollution episodes over the USA and EU through a novel analysis of ten years (2000-2010) of surface ozone measurements. An optimal interpolation scheme is developed to create grid-cell averaged values of surface ozone that can be compared with gridded model simulations. In addition, it also allows a comparison of two non-coincident observational networks in the EU. The scheme incorporates techniques borrowed from inverse distance weighting and Kriging. It uses all representative observational site data while still recognizing the heterogeneity of surface ozone. Individual, grid-cell level events are identified as an exceedance of historical percentile (10 worst days in a year, 97.3 percentile). A clustering algorithm is then used to construct the ozone episodes from the individual events. We then test the skill of the high-resolution (100 km) two-year (2005-2006) hindcast from the UCI global chemistry transport model in reproducing the events/episodes identified in the observations using the same identification criteria. Although the UCI CTM has substantial biases in surface ozone, we find that it has considerable skill in reproducing both individual grid-cell level extreme events and their connectedness in space and time with an overall skill of 24% (32%) for the US (EU). The grid-cell level extreme ozone events in both the observations and UCI CTM are found to occur mostly (~75%) in coherent, multi-day, connected episodes covering areas greater than 1000 x 1000 square km. In addition the UCI CTM has greater skill in reproducing these larger episodes. We conclude that even at relatively coarse resolution, global chemistry-climate models can be used to project major synoptic pollution episodes driven by large-scale climate and chemistry changes even with their known biases.

  10. From alginate impressions to digital virtual models: accuracy and reproducibility.

    Science.gov (United States)

    Dalstra, Michel; Melsen, Birte

    2009-03-01

    To compare the accuracy and reproducibility of measurements performed on digital virtual models with those taken on plaster casts from models poured immediately after the impression was taken, the 'gold standard', and from plaster models poured following a 3-5 day shipping procedure of the alginate impression. Direct comparison of two measuring techniques. The study was conducted at the Department of Orthodontics, School of Dentistry, University of Aarhus, Denmark in 2006/2007. Twelve randomly selected orthodontic graduate students with informed consent. Three sets of alginate impressions were taken from the participants within 1 hour. Plaster models were poured immediately from two of the sets, while the third set was kept in transit in the mail for 3-5 days. Upon return a plaster model was poured as well. Finally digital models were made from the plaster models. A number of measurements were performed on the plaster casts with a digital calliper and on the corresponding digital models using the virtual measuring tool of the accompanying software. Afterwards these measurements were compared statistically. No statistical differences were found between the three sets of plaster models. The intra- and inter-observer variability are smaller for the measurements performed on the digital models. Sending alginate impressions by mail does not affect the quality and accuracy of plaster casts poured from them afterwards. Virtual measurements performed on digital models display less variability than the corresponding measurements performed with a calliper on the actual models.

  11. A reproducible oral microcosm biofilm model for testing dental materials.

    Science.gov (United States)

    Rudney, J D; Chen, R; Lenton, P; Li, J; Li, Y; Jones, R S; Reilly, C; Fok, A S; Aparicio, C

    2012-12-01

    Most studies of biofilm effects on dental materials use single-species biofilms, or consortia. Microcosm biofilms grown directly from saliva or plaque are much more diverse, but difficult to characterize. We used the Human Oral Microbial Identification Microarray (HOMIM) to validate a reproducible oral microcosm model. Saliva and dental plaque were collected from adults and children. Hydroxyapatite and dental composite discs were inoculated with either saliva or plaque, and microcosm biofilms were grown in a CDC biofilm reactor. In later experiments, the reactor was pulsed with sucrose. DNA from inoculums and microcosms was analysed by HOMIM for 272 species. Microcosms included about 60% of species from the original inoculum. Biofilms grown on hydroxyapatite and composites were extremely similar. Sucrose pulsing decreased diversity and pH, but increased the abundance of Streptococcus and Veillonella. Biofilms from the same donor, grown at different times, clustered together. This model produced reproducible microcosm biofilms that were representative of the oral microbiota. Sucrose induced changes associated with dental caries. This is the first use of HOMIM to validate an oral microcosm model that can be used to study the effects of complex biofilms on dental materials. © 2012 The Society for Applied Microbiology.

  12. Can a coupled meteorology–chemistry model reproduce the ...

    Science.gov (United States)

    The ability of a coupled meteorology–chemistry model, i.e., Weather Research and Forecast and Community Multiscale Air Quality (WRF-CMAQ), to reproduce the historical trend in aerosol optical depth (AOD) and clear-sky shortwave radiation (SWR) over the Northern Hemisphere has been evaluated through a comparison of 21-year simulated results with observation-derived records from 1990 to 2010. Six satellite-retrieved AOD products including AVHRR, TOMS, SeaWiFS, MISR, MODIS-Terra and MODIS-Aqua as well as long-term historical records from 11 AERONET sites were used for the comparison of AOD trends. Clear-sky SWR products derived by CERES at both the top of atmosphere (TOA) and surface as well as surface SWR data derived from seven SURFRAD sites were used for the comparison of trends in SWR. The model successfully captured increasing AOD trends along with the corresponding increased TOA SWR (upwelling) and decreased surface SWR (downwelling) in both eastern China and the northern Pacific. The model also captured declining AOD trends along with the corresponding decreased TOA SWR (upwelling) and increased surface SWR (downwelling) in the eastern US, Europe and the northern Atlantic for the period of 2000–2010. However, the model underestimated the AOD over regions with substantial natural dust aerosol contributions, such as the Sahara Desert, Arabian Desert, central Atlantic and northern Indian Ocean. Estimates of the aerosol direct radiative effect (DRE) at TOA a

  13. The substorm cycle as reproduced by global MHD models

    Science.gov (United States)

    Gordeev, E.; Sergeev, V.; Tsyganenko, N.; Kuznetsova, M.; Rastäetter, L.; Raeder, J.; Tóth, G.; Lyon, J.; Merkin, V.; Wiltberger, M.

    2017-01-01

    Recently, Gordeev et al. (2015) suggested a method to test global MHD models against statistical empirical data. They showed that four community-available global MHD models supported by the Community Coordinated Modeling Center (CCMC) produce a reasonable agreement with reality for those key parameters (the magnetospheric size, magnetic field, and pressure) that are directly related to the large-scale equilibria in the outer magnetosphere. Based on the same set of simulation runs, here we investigate how the models reproduce the global loading-unloading cycle. We found that in terms of global magnetic flux transport, three examined CCMC models display systematically different response to idealized 2 h north then 2 h south interplanetary magnetic field (IMF) Bz variation. The LFM model shows a depressed return convection and high loading rate during the growth phase as well as enhanced return convection and high unloading rate during the expansion phase, with the amount of loaded/unloaded magnetotail flux and the growth phase duration being the closest to their observed empirical values during isolated substorms. Two other models exhibit drastically different behavior. In the BATS-R-US model the plasma sheet convection shows a smooth transition to the steady convection regime after the IMF southward turning. In the Open GGCM a weak plasma sheet convection has comparable intensities during both the growth phase and the following slow unloading phase. We also demonstrate potential technical problem in the publicly available simulations which is related to postprocessing interpolation and could affect the accuracy of magnetic field tracing and of other related procedures.

  14. A reproducible brain tumour model established from human glioblastoma biopsies

    Directory of Open Access Journals (Sweden)

    Li Xingang

    2009-12-01

    Full Text Available Abstract Background Establishing clinically relevant animal models of glioblastoma multiforme (GBM remains a challenge, and many commonly used cell line-based models do not recapitulate the invasive growth patterns of patient GBMs. Previously, we have reported the formation of highly invasive tumour xenografts in nude rats from human GBMs. However, implementing tumour models based on primary tissue requires that these models can be sufficiently standardised with consistently high take rates. Methods In this work, we collected data on growth kinetics from a material of 29 biopsies xenografted in nude rats, and characterised this model with an emphasis on neuropathological and radiological features. Results The tumour take rate for xenografted GBM biopsies were 96% and remained close to 100% at subsequent passages in vivo, whereas only one of four lower grade tumours engrafted. Average time from transplantation to the onset of symptoms was 125 days ± 11.5 SEM. Histologically, the primary xenografts recapitulated the invasive features of the parent tumours while endothelial cell proliferations and necrosis were mostly absent. After 4-5 in vivo passages, the tumours became more vascular with necrotic areas, but also appeared more circumscribed. MRI typically revealed changes related to tumour growth, several months prior to the onset of symptoms. Conclusions In vivo passaging of patient GBM biopsies produced tumours representative of the patient tumours, with high take rates and a reproducible disease course. The model provides combinations of angiogenic and invasive phenotypes and represents a good alternative to in vitro propagated cell lines for dissecting mechanisms of brain tumour progression.

  15. Reproducibility of qualitative assessments of temporal lobe atrophy in MRI studies.

    Science.gov (United States)

    Sarria-Estrada, S; Acevedo, C; Mitjana, R; Frascheri, L; Siurana, S; Auger, C; Rovira, A

    2015-01-01

    To determine the reproducibility of the Scheltens visual rating scale in establishing atrophy of the medial temporal lobe. We used coronal T1-weighted inversion recovery sequences on a 1.5 Tesla MRI scanner to study 25 patients with clinically diagnosed Alzheimer's disease or mild cognitive decline and 25 subjects without cognitive decline. Five neuroradiologists trained to apply the Scheltens visual rating scale analyzed the images. We used the interclass correlation coefficient to evaluate interrater and intrarater agreement. Raters scored 20 (80%) of the 25 patients with mild cognitive decline or Alzheimer's disease between 2 and 4; by contrast, they scored 21 (84%) of the 25 subjects without cognitive decline between 0 and 1. The interrater agreement was consistently greater than 0.82, with a 95% confidence interval of (0.7-0.9). The intrarater agreement ranged from 0.82 to 0.87, with a 95% confidence interval of (0.56-0.93). The Scheltens visual rating scale is reproducible among observers, and this finding supports its use in clinical practice. Copyright © 2013 SERAM. Published by Elsevier España, S.L.U. All rights reserved.

  16. Development of a Consistent and Reproducible Porcine Scald Burn Model

    Science.gov (United States)

    Kempf, Margit; Kimble, Roy; Cuttle, Leila

    2016-01-01

    There are very few porcine burn models that replicate scald injuries similar to those encountered by children. We have developed a robust porcine burn model capable of creating reproducible scald burns for a wide range of burn conditions. The study was conducted with juvenile Large White pigs, creating replicates of burn combinations; 50°C for 1, 2, 5 and 10 minutes and 60°C, 70°C, 80°C and 90°C for 5 seconds. Visual wound examination, biopsies and Laser Doppler Imaging were performed at 1, 24 hours and at 3 and 7 days post-burn. A consistent water temperature was maintained within the scald device for long durations (49.8 ± 0.1°C when set at 50°C). The macroscopic and histologic appearance was consistent between replicates of burn conditions. For 50°C water, 10 minute duration burns showed significantly deeper tissue injury than all shorter durations at 24 hours post-burn (p ≤ 0.0001), with damage seen to increase until day 3 post-burn. For 5 second duration burns, by day 7 post-burn the 80°C and 90°C scalds had damage detected significantly deeper in the tissue than the 70°C scalds (p ≤ 0.001). A reliable and safe model of porcine scald burn injury has been successfully developed. The novel apparatus with continually refreshed water improves consistency of scald creation for long exposure times. This model allows the pathophysiology of scald burn wound creation and progression to be examined. PMID:27612153

  17. Establishment of reproducible osteosarcoma rat model using orthotopic implantation technique.

    Science.gov (United States)

    Yu, Zhe; Sun, Honghui; Fan, Qingyu; Long, Hua; Yang, Tongtao; Ma, Bao'an

    2009-05-01

    osteosarcoma model was shown to be feasible: the take rate was high, surgical mortality was negligible and the procedure was simple to perform and easily reproduced. It may be a useful tool in the investigation of antiangiogenic and anticancer therapeutics. Ultrasound was found to be a highly accurate tool for tumor diagnosis, localization and measurement and may be recommended for monitoring tumor growth in this model.

  18. Qualitative and quantitative histopathology in transitional cell carcinomas of the urinary bladder. An international investigation of intra- and interobserver reproducibility

    DEFF Research Database (Denmark)

    Sørensen, Flemming Brandt; Sasaki, M; Fukuzawa, S

    1994-01-01

    .54). This can probably be related to the manual design of the sampling scheme and may be solved by introducing a motorized object stage in the systematic selection of fields of vision for quantitative measurements. However, the nuclear mean size estimators are unaffected by such sampling variability...... results. Using objective, unbiased stereologic techniques and ordinary histomorphometry, such problems may be solved. EXPERIMENTAL DESIGN: A study of 110 patients with papillary or solid transitional cell carcinomas of the urinary bladder in stage Ta through T4 was carried out, addressing reproducibility...... of both qualitative and quantitative grading methods. Grading of malignancy was performed by one observer in Japan (using the World Health Organization scheme), and by two observers in Denmark (using the Bergkvist system). A "translation" between the systems, grade for grade, and kappa statistics were...

  19. How Modeling Standards, Software, and Initiatives Support Reproducibility in Systems Biology and Systems Medicine.

    Science.gov (United States)

    Waltemath, Dagmar; Wolkenhauer, Olaf

    2016-10-01

    Only reproducible results are of significance to science. The lack of suitable standards and appropriate support of standards in software tools has led to numerous publications with irreproducible results. Our objectives are to identify the key challenges of reproducible research and to highlight existing solutions. In this paper, we summarize problems concerning reproducibility in systems biology and systems medicine. We focus on initiatives, standards, and software tools that aim to improve the reproducibility of simulation studies. The long-term success of systems biology and systems medicine depends on trustworthy models and simulations. This requires openness to ensure reusability and transparency to enable reproducibility of results in these fields.

  20. Controller Synthesis using Qualitative Models and Constraints

    OpenAIRE

    Ramamoorthy, Subramanian; Kuipers, Benjamin J

    2004-01-01

    Many engineering systems require the synthesis of global behaviors in nonlinear dynamical systems. Multiple model approaches to control design make it possible to synthesize robust and optimal versions of such global behaviors. We propose a methodology called Qualitative Heterogeneous Control that enables this type of control design. This methodology is based on a separation of concerns between qualitative correctness and quantitative optimization. Qualitative sufficient conditions are derive...

  1. Hydrological Modeling Reproducibility Through Data Management and Adaptors for Model Interoperability

    Science.gov (United States)

    Turner, M. A.

    2015-12-01

    Because of a lack of centralized planning and no widely-adopted standards among hydrological modeling research groups, research communities, and the data management teams meant to support research, there is chaos when it comes to data formats, spatio-temporal resolutions, ontologies, and data availability. All this makes true scientific reproducibility and collaborative integrated modeling impossible without some glue to piece it all together. Our Virtual Watershed Integrated Modeling System provides the tools and modeling framework hydrologists need to accelerate and fortify new scientific investigations by tracking provenance and providing adaptors for integrated, collaborative hydrologic modeling and data management. Under global warming trends where water resources are under increasing stress, reproducible hydrological modeling will be increasingly important to improve transparency and understanding of the scientific facts revealed through modeling. The Virtual Watershed Data Engine is capable of ingesting a wide variety of heterogeneous model inputs, outputs, model configurations, and metadata. We will demonstrate one example, starting from real-time raw weather station data packaged with station metadata. Our integrated modeling system will then create gridded input data via geostatistical methods along with error and uncertainty estimates. These gridded data are then used as input to hydrological models, all of which are available as web services wherever feasible. Models may be integrated in a data-centric way where the outputs too are tracked and used as inputs to "downstream" models. This work is part of an ongoing collaborative Tri-state (New Mexico, Nevada, Idaho) NSF EPSCoR Project, WC-WAVE, comprised of researchers from multiple universities in each of the three states. The tools produced and presented here have been developed collaboratively alongside watershed scientists to address specific modeling problems with an eye on the bigger picture of

  2. Reproducing Phenomenology of Peroxidation Kinetics via Model Optimization

    Science.gov (United States)

    Ruslanov, Anatole D.; Bashylau, Anton V.

    2010-06-01

    We studied mathematical modeling of lipid peroxidation using a biochemical model system of iron (II)-ascorbate-dependent lipid peroxidation of rat hepatocyte mitochondrial fractions. We found that antioxidants extracted from plants demonstrate a high intensity of peroxidation inhibition. We simplified the system of differential equations that describes the kinetics of the mathematical model to a first order equation, which can be solved analytically. Moreover, we endeavor to algorithmically and heuristically recreate the processes and construct an environment that closely resembles the corresponding natural system. Our results demonstrate that it is possible to theoretically predict both the kinetics of oxidation and the intensity of inhibition without resorting to analytical and biochemical research, which is important for cost-effective discovery and development of medical agents with antioxidant action from the medicinal plants.

  3. Qualitative models for space system engineering

    Science.gov (United States)

    Forbus, Kenneth D.

    1990-01-01

    The objectives of this project were: (1) to investigate the implications of qualitative modeling techniques for problems arising in the monitoring, diagnosis, and design of Space Station subsystems and procedures; (2) to identify the issues involved in using qualitative models to enhance and automate engineering functions. These issues include representing operational criteria, fault models, alternate ontologies, and modeling continuous signals at a functional level of description; and (3) to develop a prototype collection of qualitative models for fluid and thermal systems commonly found in Space Station subsystems. Potential applications of qualitative modeling to space-systems engineering, including the notion of intelligent computer-aided engineering are summarized. Emphasis is given to determining which systems of the proposed Space Station provide the most leverage for study, given the current state of the art. Progress on using qualitative models, including development of the molecular collection ontology for reasoning about fluids, the interaction of qualitative and quantitative knowledge in analyzing thermodynamic cycles, and an experiment on building a natural language interface to qualitative reasoning is reported. Finally, some recommendations are made for future research.

  4. Using a 1-D model to reproduce diurnal SST signals

    DEFF Research Database (Denmark)

    Karagali, Ioanna; Høyer, Jacob L.

    2014-01-01

    of measurement. A generally preferred approach to bridge the gap between in situ and remotely obtained measurements is through modelling of the upper ocean temperature. This ESA supported study focuses on the implementation of the 1 dimensional General Ocean Turbulence Model (GOTM), in order to resolve...... an additional parametrisation for the total outgoing long-wave radiation and a 9-band parametrisation for the light extinction. New parametrisations for the stability functions, associated with vertical mixing, have been included. GOTM is tested using experimental data from the Woods Hole Oceanographic...

  5. Reproducible Infection Model for Clostridium perfringens in Broiler Chickens

    DEFF Research Database (Denmark)

    Pedersen, Karl; Friis-Holm, Lotte Bjerrum; Heuer, Ole Eske

    2008-01-01

    Experiments were carried out to establish an infection and disease model for Clostridium perfringens in broiler chickens. Previous experiments had failed to induce disease and only a transient colonization with challenge strains had been obtained. In the present study, two series of experiments...

  6. Learning Action Models: Qualitative Approach

    NARCIS (Netherlands)

    Bolander, T.; Gierasimczuk, N.; van der Hoek, W.; Holliday, W.H.; Wang, W.-F.

    2015-01-01

    In dynamic epistemic logic, actions are described using action models. In this paper we introduce a framework for studying learnability of action models from observations. We present first results concerning propositional action models. First we check two basic learnability criteria: finite

  7. COMBINE archive and OMEX format : One file to share all information to reproduce a modeling project

    NARCIS (Netherlands)

    Bergmann, Frank T.; Olivier, Brett G.; Soiland-Reyes, Stian

    2014-01-01

    Background: With the ever increasing use of computational models in the biosciences, the need to share models and reproduce the results of published studies efficiently and easily is becoming more important. To this end, various standards have been proposed that can be used to describe models,

  8. Learning Actions Models: Qualitative Approach

    DEFF Research Database (Denmark)

    Bolander, Thomas; Gierasimczuk, Nina

    2015-01-01

    —they are identifiable in the limit.We then move on to a particular learning method, which proceeds via restriction of a space of events within a learning-specific action model. This way of learning closely resembles the well-known update method from dynamic epistemic logic. We introduce several different learning...... identifiability (conclusively inferring the appropriate action model in finite time) and identifiability in the limit (inconclusive convergence to the right action model). We show that deterministic actions are finitely identifiable, while non-deterministic actions require more learning power...... methods suited for finite identifiability of particular types of deterministic actions....

  9. Qualitative models of global warming amplifiers

    NARCIS (Netherlands)

    Milošević, U.; Bredeweg, B.; de Kleer, J.; Forbus, K.D.

    2010-01-01

    There is growing interest from ecological experts to create qualitative models of phenomena for which numerical information is sparse or missing. We present a number of successful models in the field of environmental science, namely, the domain of global warming. The motivation behind the effort is

  10. Voxel-level reproducibility assessment of modality independent elastography in a pre-clinical murine model

    Science.gov (United States)

    Flint, Katelyn M.; Weis, Jared A.; Yankeelov, Thomas E.; Miga, Michael I.

    2015-03-01

    Changes in tissue mechanical properties, measured non-invasively by elastography methods, have been shown to be an important diagnostic tool, particularly for cancer. Tissue elasticity information, tracked over the course of therapy, may be an important prognostic indicator of tumor response to treatment. While many elastography techniques exist, this work reports on the use of a novel form of elastography that uses image texture to reconstruct elastic property distributions in tissue (i.e., a modality independent elastography (MIE) method) within the context of a pre-clinical breast cancer system.1,2 The elasticity results have previously shown good correlation with independent mechanical testing.1 Furthermore, MIE has been successfully utilized to localize and characterize lesions in both phantom experiments and simulation experiments with clinical data.2,3 However, the reproducibility of this method has not been characterized in previous work. The goal of this study is to evaluate voxel-level reproducibility of MIE in a pre-clinical model of breast cancer. Bland-Altman analysis of co-registered repeat MIE scans in this preliminary study showed a reproducibility index of 24.7% (scaled to a percent of maximum stiffness) at the voxel level. As opposed to many reports in the magnetic resonance elastography (MRE) literature that speak to reproducibility measures of the bulk organ, these results establish MIE reproducibility at the voxel level; i.e., the reproducibility of locally-defined mechanical property measurements throughout the tumor volume.

  11. Qualitative and quantitative histopathology in transitional cell carcinomas of the urinary bladder. An international investigation of intra- and interobserver reproducibility

    DEFF Research Database (Denmark)

    Sørensen, Flemming Brandt; Sasaki, M; Fukuzawa, S

    1994-01-01

    BACKGROUND: Histopathologic, prognosis-related grading of malignancy by means of morphologic examination in transitional cell carcinomas of the urinary bladder (TCC) may be subject to observer variation, resulting in a reduced level of reproducibility. This may confound comparisons of treatment r...

  12. A Qualitative Acceleration Model Based on Intervals

    Directory of Open Access Journals (Sweden)

    Ester MARTINEZ-MARTIN

    2013-08-01

    Full Text Available On the way to autonomous service robots, spatial reasoning plays a main role since it properly deals with problems involving uncertainty. In particular, we are interested in knowing people's pose to avoid collisions. With that aim, in this paper, we present a qualitative acceleration model for robotic applications including representation, reasoning and a practical application.

  13. Investigation of dimensional variation in parts manufactured by fused deposition modeling using Gauge Repeatability and Reproducibility

    Science.gov (United States)

    Mohamed, Omar Ahmed; Hasan Masood, Syed; Lal Bhowmik, Jahar

    2018-02-01

    In the additive manufacturing (AM) market, the question is raised by industry and AM users on how reproducible and repeatable the fused deposition modeling (FDM) process is in providing good dimensional accuracy. This paper aims to investigate and evaluate the repeatability and reproducibility of the FDM process through a systematic approach to answer this frequently asked question. A case study based on the statistical gage repeatability and reproducibility (gage R&R) technique is proposed to investigate the dimensional variations in the printed parts of the FDM process. After running the simulation and analysis of the data, the FDM process capability is evaluated, which would help the industry for better understanding the performance of FDM technology.

  14. Qualitative modeling of the dynamics of detonations with losses

    KAUST Repository

    Faria, Luiz

    2015-01-01

    We consider a simplified model for the dynamics of one-dimensional detonations with generic losses. It consists of a single partial differential equation that reproduces, at a qualitative level, the essential properties of unsteady detonation waves, including pulsating and chaotic solutions. In particular, we investigate the effects of shock curvature and friction losses on detonation dynamics. To calculate steady-state solutions, a novel approach to solving the detonation eigenvalue problem is introduced that avoids the well-known numerical difficulties associated with the presence of a sonic point. By using unsteady numerical simulations of the simplified model, we also explore the nonlinear stability of steady-state or quasi-steady solutions. © 2014 The Combustion Institute.

  15. Using the mouse to model human disease: increasing validity and reproducibility

    Directory of Open Access Journals (Sweden)

    Monica J. Justice

    2016-02-01

    Full Text Available Experiments that use the mouse as a model for disease have recently come under scrutiny because of the repeated failure of data, particularly derived from preclinical studies, to be replicated or translated to humans. The usefulness of mouse models has been questioned because of irreproducibility and poor recapitulation of human conditions. Newer studies, however, point to bias in reporting results and improper data analysis as key factors that limit reproducibility and validity of preclinical mouse research. Inaccurate and incomplete descriptions of experimental conditions also contribute. Here, we provide guidance on best practice in mouse experimentation, focusing on appropriate selection and validation of the model, sources of variation and their influence on phenotypic outcomes, minimum requirements for control sets, and the importance of rigorous statistics. Our goal is to raise the standards in mouse disease modeling to enhance reproducibility, reliability and clinical translation of findings.

  16. Qualitative simulation in formal process modelling

    International Nuclear Information System (INIS)

    Sivertsen, Elin R.

    1999-01-01

    In relation to several different research activities at the OECD Halden Reactor Project, the usefulness of formal process models has been identified. Being represented in some appropriate representation language, the purpose of these models is to model process plants and plant automatics in a unified way to allow verification and computer aided design of control strategies. The present report discusses qualitative simulation and the tool QSIM as one approach to formal process models. In particular, the report aims at investigating how recent improvements of the tool facilitate the use of the approach in areas like process system analysis, procedure verification, and control software safety analysis. An important long term goal is to provide a basis for using qualitative reasoning in combination with other techniques to facilitate the treatment of embedded programmable systems in Probabilistic Safety Analysis (PSA). This is motivated from the potential of such a combination in safety analysis based on models comprising both software, hardware, and operator. It is anticipated that the research results from this activity will benefit V and V in a wide variety of applications where formal process models can be utilized. Examples are operator procedures, intelligent decision support systems, and common model repositories (author) (ml)

  17. Reproducibility of the coil positioning in Nb$_3$Sn magnet models through magnetic measurements

    CERN Document Server

    Borgnolutti, F; Ferracin, P; Kashikhin, V V; Sabbi, G; Velev, G; Todesco, E; Zlobin, A V

    2009-01-01

    The random part of the integral field harmonics in a series of superconducting magnets has been used in the past to identify the reproducibility of the coil positioning. Using a magnetic model and a MonteCarlo approach, coil blocks are randomly moved and the amplitude that best fits the magnetic measurements is interpreted as the reproducibility of the coil position. Previous values for r.m.s. coil displacements for Nb-Ti magnets range from 0.05 to 0.01 mm. In this paper, we use this approach to estimate the reproducibility in the coil position for Nb3Sn short models that have been built in the framework of the FNAL core program (HFDA dipoles) and of the LARP program (TQ quadrupoles). Our analysis shows that the Nb3Sn models manufactured in the past years correspond to r.m.s. coil displacements of at least 5 times what is found for the series production of a mature Nb-Ti technology. On the other hand, the variability of the field harmonics along the magnet axis shows that Nb3Sn magnets have already reached va...

  18. Cellular automaton model in the fundamental diagram approach reproducing the synchronized outflow of wide moving jams

    International Nuclear Information System (INIS)

    Tian, Jun-fang; Yuan, Zhen-zhou; Jia, Bin; Fan, Hong-qiang; Wang, Tao

    2012-01-01

    Velocity effect and critical velocity are incorporated into the average space gap cellular automaton model [J.F. Tian, et al., Phys. A 391 (2012) 3129], which was able to reproduce many spatiotemporal dynamics reported by the three-phase theory except the synchronized outflow of wide moving jams. The physics of traffic breakdown has been explained. Various congested patterns induced by the on-ramp are reproduced. It is shown that the occurrence of synchronized outflow, free outflow of wide moving jams is closely related with drivers time delay in acceleration at the downstream jam front and the critical velocity, respectively. -- Highlights: ► Velocity effect is added into average space gap cellular automaton model. ► The physics of traffic breakdown has been explained. ► The probabilistic nature of traffic breakdown is simulated. ► Various congested patterns induced by the on-ramp are reproduced. ► The occurrence of synchronized outflow of jams depends on drivers time delay.

  19. SBML qualitative models: a model representation format and infrastructure to foster interactions between qualitative modelling formalisms and tools.

    Science.gov (United States)

    Chaouiya, Claudine; Bérenguier, Duncan; Keating, Sarah M; Naldi, Aurélien; van Iersel, Martijn P; Rodriguez, Nicolas; Dräger, Andreas; Büchel, Finja; Cokelaer, Thomas; Kowal, Bryan; Wicks, Benjamin; Gonçalves, Emanuel; Dorier, Julien; Page, Michel; Monteiro, Pedro T; von Kamp, Axel; Xenarios, Ioannis; de Jong, Hidde; Hucka, Michael; Klamt, Steffen; Thieffry, Denis; Le Novère, Nicolas; Saez-Rodriguez, Julio; Helikar, Tomáš

    2013-12-10

    Qualitative frameworks, especially those based on the logical discrete formalism, are increasingly used to model regulatory and signalling networks. A major advantage of these frameworks is that they do not require precise quantitative data, and that they are well-suited for studies of large networks. While numerous groups have developed specific computational tools that provide original methods to analyse qualitative models, a standard format to exchange qualitative models has been missing. We present the Systems Biology Markup Language (SBML) Qualitative Models Package ("qual"), an extension of the SBML Level 3 standard designed for computer representation of qualitative models of biological networks. We demonstrate the interoperability of models via SBML qual through the analysis of a specific signalling network by three independent software tools. Furthermore, the collective effort to define the SBML qual format paved the way for the development of LogicalModel, an open-source model library, which will facilitate the adoption of the format as well as the collaborative development of algorithms to analyse qualitative models. SBML qual allows the exchange of qualitative models among a number of complementary software tools. SBML qual has the potential to promote collaborative work on the development of novel computational approaches, as well as on the specification and the analysis of comprehensive qualitative models of regulatory and signalling networks.

  20. NRFixer: Sentiment Based Model for Predicting the Fixability of Non-Reproducible Bugs

    Directory of Open Access Journals (Sweden)

    Anjali Goyal

    2017-08-01

    Full Text Available Software maintenance is an essential step in software development life cycle. Nowadays, software companies spend approximately 45\\% of total cost in maintenance activities. Large software projects maintain bug repositories to collect, organize and resolve bug reports. Sometimes it is difficult to reproduce the reported bug with the information present in a bug report and thus this bug is marked with resolution non-reproducible (NR. When NR bugs are reconsidered, a few of them might get fixed (NR-to-fix leaving the others with the same resolution (NR. To analyse the behaviour of developers towards NR-to-fix and NR bugs, the sentiment analysis of NR bug report textual contents has been conducted. The sentiment analysis of bug reports shows that NR bugs' sentiments incline towards more negativity than reproducible bugs. Also, there is a noticeable opinion drift found in the sentiments of NR-to-fix bug reports. Observations driven from this analysis were an inspiration to develop a model that can judge the fixability of NR bugs. Thus a framework, {NRFixer,} which predicts the probability of NR bug fixation, is proposed. {NRFixer} was evaluated with two dimensions. The first dimension considers meta-fields of bug reports (model-1 and the other dimension additionally incorporates the sentiments (model-2 of developers for prediction. Both models were compared using various machine learning classifiers (Zero-R, naive Bayes, J48, random tree and random forest. The bug reports of Firefox and Eclipse projects were used to test {NRFixer}. In Firefox and Eclipse projects, J48 and Naive Bayes classifiers achieve the best prediction accuracy, respectively. It was observed that the inclusion of sentiments in the prediction model shows a rise in the prediction accuracy ranging from 2 to 5\\% for various classifiers.

  1. Reproducing Sea-Ice Deformation Distributions With Viscous-Plastic Sea-Ice Models

    Science.gov (United States)

    Bouchat, A.; Tremblay, B.

    2016-02-01

    High resolution sea-ice dynamic models offer the potential to discriminate between sea-ice rheologies based on their ability to reproduce the satellite-derived deformation fields. Recent studies have shown that sea-ice viscous-plastic (VP) models do not reproduce the observed statistical properties of the strain rate distributions of the RADARSAT Geophysical Processor System (RGPS) deformation fields [1][2]. We use the elliptical VP rheology and we compute the probability density functions (PDFs) for simulated strain rate invariants (divergence and maximum shear stress) and compare against the deformations obtained with the 3-day gridded products from RGPS. We find that the large shear deformations are well reproduced by the elliptical VP model and the deformations do not follow a Gaussian distribution as reported in Girard et al. [1][2]. On the other hand, we do find an overestimation of the shear in the range of mid-magnitude deformations in all of our VP simulations tested with different spatial resolutions and numerical parameters. Runs with no internal stress (free-drift) or with constant viscosity coefficients (Newtonian fluid) also show this overestimation. We trace back this discrepancy to the elliptical yield curve aspect ratio (e = 2) having too little shear strength, hence not resisting enough the inherent shear in the wind forcing associated with synoptic weather systems. Experiments where we simply increase the shear resistance of the ice by modifying the ellipse ratio confirm the need for a rheology with an increased shear strength. [1] Girard et al. (2009), Evaluation of high-resolution sea ice models [...], Journal of Geophysical Research, 114[2] Girard et al. (2011), A new modeling framework for sea-ice mechanics [...], Annals of Glaciology, 57, 123-132

  2. Evaluation of fecal mRNA reproducibility via a marginal transformed mixture modeling approach

    Directory of Open Access Journals (Sweden)

    Davidson Laurie A

    2010-01-01

    Full Text Available Abstract Background Developing and evaluating new technology that enables researchers to recover gene-expression levels of colonic cells from fecal samples could be key to a non-invasive screening tool for early detection of colon cancer. The current study, to the best of our knowledge, is the first to investigate and report the reproducibility of fecal microarray data. Using the intraclass correlation coefficient (ICC as a measure of reproducibility and the preliminary analysis of fecal and mucosal data, we assessed the reliability of mixture density estimation and the reproducibility of fecal microarray data. Using Monte Carlo-based methods, we explored whether ICC values should be modeled as a beta-mixture or transformed first and fitted with a normal-mixture. We used outcomes from bootstrapped goodness-of-fit tests to determine which approach is less sensitive toward potential violation of distributional assumptions. Results The graphical examination of both the distributions of ICC and probit-transformed ICC (PT-ICC clearly shows that there are two components in the distributions. For ICC measurements, which are between 0 and 1, the practice in literature has been to assume that the data points are from a beta-mixture distribution. Nevertheless, in our study we show that the use of a normal-mixture modeling approach on PT-ICC could provide superior performance. Conclusions When modeling ICC values of gene expression levels, using mixture of normals in the probit-transformed (PT scale is less sensitive toward model mis-specification than using mixture of betas. We show that a biased conclusion could be made if we follow the traditional approach and model the two sets of ICC values using the mixture of betas directly. The problematic estimation arises from the sensitivity of beta-mixtures toward model mis-specification, particularly when there are observations in the neighborhood of the the boundary points, 0 or 1. Since beta-mixture modeling

  3. Reproducing the optical properties of fine desert dust aerosols using ensembles of simple model particles

    International Nuclear Information System (INIS)

    Kahnert, Michael

    2004-01-01

    Single scattering optical properties are calculated for a proxy of fine dust aerosols at a wavelength of 0.55 μm. Spherical and spheroidal model particles are employed to fit the aerosol optical properties and to retrieve information about the physical parameters characterising the aerosols. It is found that spherical particles are capable of reproducing the scalar optical properties and the forward peak of the phase function of the dust aerosols. The effective size parameter of the aerosol ensemble is retrieved with high accuracy by using spherical model particles. Significant improvements are achieved by using spheroidal model particles. The aerosol phase function and the other diagonal elements of the Stokes scattering matrix can be fitted with high accuracy, whereas the off-diagonal elements are poorly reproduced. More elongated prolate and more flattened oblate spheroids contribute disproportionately strongly to the optimised shape distribution of the model particles and appear to be particularly useful for achieving a good fit of the scattering matrix. However, the clear discrepancies between the shape distribution of the aerosols and the shape distribution of the spheroidal model particles suggest that the possibilities of extracting shape information from optical observations are rather limited

  4. A novel highly reproducible and lethal nonhuman primate model for orthopox virus infection.

    Directory of Open Access Journals (Sweden)

    Marit Kramski

    Full Text Available The intentional re-introduction of Variola virus (VARV, the agent of smallpox, into the human population is of great concern due its bio-terroristic potential. Moreover, zoonotic infections with Cowpox (CPXV and Monkeypox virus (MPXV cause severe diseases in humans. Smallpox vaccines presently available can have severe adverse effects that are no longer acceptable. The efficacy and safety of new vaccines and antiviral drugs for use in humans can only be demonstrated in animal models. The existing nonhuman primate models, using VARV and MPXV, need very high viral doses that have to be applied intravenously or intratracheally to induce a lethal infection in macaques. To overcome these drawbacks, the infectivity and pathogenicity of a particular CPXV was evaluated in the common marmoset (Callithrix jacchus.A CPXV named calpox virus was isolated from a lethal orthopox virus (OPV outbreak in New World monkeys. We demonstrated that marmosets infected with calpox virus, not only via the intravenous but also the intranasal route, reproducibly develop symptoms resembling smallpox in humans. Infected animals died within 1-3 days after onset of symptoms, even when very low infectious viral doses of 5x10(2 pfu were applied intranasally. Infectious virus was demonstrated in blood, saliva and all organs analyzed.We present the first characterization of a new OPV infection model inducing a disease in common marmosets comparable to smallpox in humans. Intranasal virus inoculation mimicking the natural route of smallpox infection led to reproducible infection. In vivo titration resulted in an MID(50 (minimal monkey infectious dose 50% of 8.3x10(2 pfu of calpox virus which is approximately 10,000-fold lower than MPXV and VARV doses applied in the macaque models. Therefore, the calpox virus/marmoset model is a suitable nonhuman primate model for the validation of vaccines and antiviral drugs. Furthermore, this model can help study mechanisms of OPV pathogenesis.

  5. Diagnostic reasoning using qualitative causal models

    International Nuclear Information System (INIS)

    Sudduth, A.L.

    1992-01-01

    The application of expert systems to reasoning problems involving real-time data from plant measurements has been a topic of much research, but few practical systems have been deployed. One obstacle to wider use of expert systems in applications involving real-time data is the lack of adequate knowledge representation methodologies for dynamic processes. Knowledge bases composed mainly of rules have disadvantages when applied to dynamic processes and real-time data. This paper describes a methodology for the development of qualitative causal models that can be used as knowledge bases for reasoning about process dynamic behavior. These models provide a systematic method for knowledge base construction, considerably reducing the engineering effort required. They also offer much better opportunities for verification and validation of the knowledge base, thus increasing the possibility of the application of expert systems to reasoning about mission critical systems. Starting with the Signed Directed Graph (SDG) method that has been successfully applied to describe the behavior of diverse dynamic processes, the paper shows how certain non-physical behaviors that result from abstraction may be eliminated by applying causal constraint to the models. The resulting Extended Signed Directed Graph (ESDG) may then be compiled to produce a model for use in process fault diagnosis. This model based reasoning methodology is used in the MOBIAS system being developed by Duke Power Company under EPRI sponsorship. 15 refs., 4 figs

  6. Reproducing tailing in breakthrough curves: Are statistical models equally representative and predictive?

    Science.gov (United States)

    Pedretti, Daniele; Bianchi, Marco

    2018-03-01

    Breakthrough curves (BTCs) observed during tracer tests in highly heterogeneous aquifers display strong tailing. Power laws are popular models for both the empirical fitting of these curves, and the prediction of transport using upscaling models based on best-fitted estimated parameters (e.g. the power law slope or exponent). The predictive capacity of power law based upscaling models can be however questioned due to the difficulties to link model parameters with the aquifers' physical properties. This work analyzes two aspects that can limit the use of power laws as effective predictive tools: (a) the implication of statistical subsampling, which often renders power laws undistinguishable from other heavily tailed distributions, such as the logarithmic (LOG); (b) the difficulties to reconcile fitting parameters obtained from models with different formulations, such as the presence of a late-time cutoff in the power law model. Two rigorous and systematic stochastic analyses, one based on benchmark distributions and the other on BTCs obtained from transport simulations, are considered. It is found that a power law model without cutoff (PL) results in best-fitted exponents (αPL) falling in the range of typical experimental values reported in the literature (1.5 constant αCO ≈ 1. In the PLCO model, the cutoff rate (λ) is the parameter that fully reproduces the persistence of the tailing and is shown to be inversely correlated to the LOG scale parameter (i.e. with the skewness of the distribution). The theoretical results are consistent with the fitting analysis of a tracer test performed during the MADE-5 experiment. It is shown that a simple mechanistic upscaling model based on the PLCO formulation is able to predict the ensemble of BTCs from the stochastic transport simulations without the need of any fitted parameters. The model embeds the constant αCO = 1 and relies on a stratified description of the transport mechanisms to estimate λ. The PL fails to

  7. [Reproducibility and repeatability of the determination of occlusal plane on digital dental models].

    Science.gov (United States)

    Qin, Yi-fei; Xu, Tian-min

    2015-06-18

    To assess the repeatability(intraobserver comparison)and reproducibility(interobserver comparison)of two different methods for establishing the occlusal plane on digital dental models. With Angle's classification as a stratification factor,48 cases were randomly extracted from 806 ones which had integrated clinical data and had their orthodontic treatment from July 2004 to August 2008 in Department of Orthodontics ,Peking University School and Hospital of Stomatology.Post-treatment plaster casts of 48 cases were scanned by Roland LPX-1200 3D laser scanner to generate geometry data as research subjects.In a locally developed software package,one observer repeated 5 times at intervals of at least one week to localize prescriptive landmarks on each digital model to establish a group of functional occlusal planes and a group of anatomic occlusal planes, while 6 observers established two other groups of functional and anatomic occlusal planes independently.Standard deviations of dihedral angles of each group on each model were calculated and compared between the related groups.The models with the five largest standard deviations of each group were studied to explore possible factors that might influence the identification of the landmarks on the digital models. Significant difference of intraobserver variability was not detected between the functional occlusal plane and the anatomic occlusal plane (P>0.1), while that of interobserver variability was detected (Pocclusal plane was 0.2° smaller than that of the anatomic occlusal plane.The functional occlusal plane's variability of intraobserver and interobsever did not differ significantly (P>0.1), while the anatomic occlusal plane's variability of the intraobserver was significantly smaller than that of the interobserver (Pocclusal planes are suitable as a conference plane with equal repeatability. When several observers measure a large number of digital models,the functional occlusal plane is more reproducible than the

  8. Reproducibility, reliability and validity of measurements obtained from Cecile3 digital models

    Directory of Open Access Journals (Sweden)

    Gustavo Adolfo Watanabe-Kanno

    2009-09-01

    Full Text Available The aim of this study was to determine the reproducibility, reliability and validity of measurements in digital models compared to plaster models. Fifteen pairs of plaster models were obtained from orthodontic patients with permanent dentition before treatment. These were digitized to be evaluated with the program Cécile3 v2.554.2 beta. Two examiners measured three times the mesiodistal width of all the teeth present, intercanine, interpremolar and intermolar distances, overjet and overbite. The plaster models were measured using a digital vernier. The t-Student test for paired samples and interclass correlation coefficient (ICC were used for statistical analysis. The ICC of the digital models were 0.84 ± 0.15 (intra-examiner and 0.80 ± 0.19 (inter-examiner. The average mean difference of the digital models was 0.23 ± 0.14 and 0.24 ± 0.11 for each examiner, respectively. When the two types of measurements were compared, the values obtained from the digital models were lower than those obtained from the plaster models (p < 0.05, although the differences were considered clinically insignificant (differences < 0.1 mm. The Cécile digital models are a clinically acceptable alternative for use in Orthodontics.

  9. Qualitative model-based diagnosis using possibility theory

    Science.gov (United States)

    Joslyn, Cliff

    1994-01-01

    The potential for the use of possibility in the qualitative model-based diagnosis of spacecraft systems is described. The first sections of the paper briefly introduce the Model-Based Diagnostic (MBD) approach to spacecraft fault diagnosis; Qualitative Modeling (QM) methodologies; and the concepts of possibilistic modeling in the context of Generalized Information Theory (GIT). Then the necessary conditions for the applicability of possibilistic methods to qualitative MBD, and a number of potential directions for such an application, are described.

  10. Reproducing the nonlinear dynamic behavior of a structured beam with a generalized continuum model

    Science.gov (United States)

    Vila, J.; Fernández-Sáez, J.; Zaera, R.

    2018-04-01

    In this paper we study the coupled axial-transverse nonlinear vibrations of a kind of one dimensional structured solids by application of the so called Inertia Gradient Nonlinear continuum model. To show the accuracy of this axiomatic model, previously proposed by the authors, its predictions are compared with numeric results from a previously defined finite discrete chain of lumped masses and springs, for several number of particles. A continualization of the discrete model equations based on Taylor series allowed us to set equivalent values of the mechanical properties in both discrete and axiomatic continuum models. Contrary to the classical continuum model, the inertia gradient nonlinear continuum model used herein is able to capture scale effects, which arise for modes in which the wavelength is comparable to the characteristic distance of the structured solid. The main conclusion of the work is that the proposed generalized continuum model captures the scale effects in both linear and nonlinear regimes, reproducing the behavior of the 1D nonlinear discrete model adequately.

  11. Assessment of the reliability of reproducing two-dimensional resistivity models using an image processing technique.

    Science.gov (United States)

    Ishola, Kehinde S; Nawawi, Mohd Nm; Abdullah, Khiruddin; Sabri, Ali Idriss Aboubakar; Adiat, Kola Abdulnafiu

    2014-01-01

    This study attempts to combine the results of geophysical images obtained from three commonly used electrode configurations using an image processing technique in order to assess their capabilities to reproduce two-dimensional (2-D) resistivity models. All the inverse resistivity models were processed using the PCI Geomatica software package commonly used for remote sensing data sets. Preprocessing of the 2-D inverse models was carried out to facilitate further processing and statistical analyses. Four Raster layers were created, three of these layers were used for the input images and the fourth layer was used as the output of the combined images. The data sets were merged using basic statistical approach. Interpreted results show that all images resolved and reconstructed the essential features of the models. An assessment of the accuracy of the images for the four geologic models was performed using four criteria: the mean absolute error and mean percentage absolute error, resistivity values of the reconstructed blocks and their displacements from the true models. Generally, the blocks of the images of maximum approach give the least estimated errors. Also, the displacement of the reconstructed blocks from the true blocks is the least and the reconstructed resistivities of the blocks are closer to the true blocks than any other combined used. Thus, it is corroborated that when inverse resistivity models are combined, most reliable and detailed information about the geologic models is obtained than using individual data sets.

  12. The substorm loading-unloading cycle as reproduced by community-available global MHD magnetospheric models

    Science.gov (United States)

    Gordeev, Evgeny; Sergeev, Victor; Tsyganenko, Nikolay; Kuznetsova, Maria; Rastaetter, Lutz; Raeder, Joachim; Toth, Gabor; Lyon, John; Merkin, Vyacheslav; Wiltberger, Michael

    2017-04-01

    In this study we investigate how well the three community-available global MHD models, supported by the Community Coordinated Modeling Center (CCMC NASA), reproduce the global magnetospheric dynamics, including the loading-unloading substorm cycle. We found that in terms of global magnetic flux transport CCMC models display systematically different response to idealized 2-hour north then 2-hour south IMF Bz variation. The LFM model shows a depressed return convection in the tail plasma sheet and high rate of magnetic flux loading into the lobes during the growth phase, as well as enhanced return convection and high unloading rate during the expansion phase, with the amount of loaded/unloaded magnetotail flux and the growth phase duration being the closest to their observed empirical values during isolated substorms. BATSRUS and Open GGCM models exhibit drastically different behavior. In the BATS-R-US model the plasma sheet convection shows a smooth transition to the steady convection regime after the IMF southward turning. In the Open GGCM a weak plasma sheet convection has comparable intensities during both the growth phase and the following slow unloading phase. Our study shows that different CCMC models under the same solar wind conditions (north to south IMF variation) produce essentially different solutions in terms of global magnetospheric convection.

  13. Mouse Models of Diet-Induced Nonalcoholic Steatohepatitis Reproduce the Heterogeneity of the Human Disease

    Science.gov (United States)

    Machado, Mariana Verdelho; Michelotti, Gregory Alexander; Xie, Guanhua; de Almeida, Thiago Pereira; Boursier, Jerome; Bohnic, Brittany; Guy, Cynthia D.; Diehl, Anna Mae

    2015-01-01

    Background and aims Non-alcoholic steatohepatitis (NASH), the potentially progressive form of nonalcoholic fatty liver disease (NAFLD), is the pandemic liver disease of our time. Although there are several animal models of NASH, consensus regarding the optimal model is lacking. We aimed to compare features of NASH in the two most widely-used mouse models: methionine-choline deficient (MCD) diet and Western diet. Methods Mice were fed standard chow, MCD diet for 8 weeks, or Western diet (45% energy from fat, predominantly saturated fat, with 0.2% cholesterol, plus drinking water supplemented with fructose and glucose) for 16 weeks. Liver pathology and metabolic profile were compared. Results The metabolic profile associated with human NASH was better mimicked by Western diet. Although hepatic steatosis (i.e., triglyceride accumulation) was also more severe, liver non-esterified fatty acid content was lower than in the MCD diet group. NASH was also less severe and less reproducible in the Western diet model, as evidenced by less liver cell death/apoptosis, inflammation, ductular reaction, and fibrosis. Various mechanisms implicated in human NASH pathogenesis/progression were also less robust in the Western diet model, including oxidative stress, ER stress, autophagy deregulation, and hedgehog pathway activation. Conclusion Feeding mice a Western diet models metabolic perturbations that are common in humans with mild NASH, whereas administration of a MCD diet better models the pathobiological mechanisms that cause human NAFLD to progress to advanced NASH. PMID:26017539

  14. Mouse models of diet-induced nonalcoholic steatohepatitis reproduce the heterogeneity of the human disease.

    Directory of Open Access Journals (Sweden)

    Mariana Verdelho Machado

    Full Text Available Non-alcoholic steatohepatitis (NASH, the potentially progressive form of nonalcoholic fatty liver disease (NAFLD, is the pandemic liver disease of our time. Although there are several animal models of NASH, consensus regarding the optimal model is lacking. We aimed to compare features of NASH in the two most widely-used mouse models: methionine-choline deficient (MCD diet and Western diet.Mice were fed standard chow, MCD diet for 8 weeks, or Western diet (45% energy from fat, predominantly saturated fat, with 0.2% cholesterol, plus drinking water supplemented with fructose and glucose for 16 weeks. Liver pathology and metabolic profile were compared.The metabolic profile associated with human NASH was better mimicked by Western diet. Although hepatic steatosis (i.e., triglyceride accumulation was also more severe, liver non-esterified fatty acid content was lower than in the MCD diet group. NASH was also less severe and less reproducible in the Western diet model, as evidenced by less liver cell death/apoptosis, inflammation, ductular reaction, and fibrosis. Various mechanisms implicated in human NASH pathogenesis/progression were also less robust in the Western diet model, including oxidative stress, ER stress, autophagy deregulation, and hedgehog pathway activation.Feeding mice a Western diet models metabolic perturbations that are common in humans with mild NASH, whereas administration of a MCD diet better models the pathobiological mechanisms that cause human NAFLD to progress to advanced NASH.

  15. Circuit modeling of the electrical impedance: II. Normal subjects and system reproducibility

    International Nuclear Information System (INIS)

    Shiffman, C A; Rutkove, S B

    2013-01-01

    Part I of this series showed that the five-element circuit model accurately mimics impedances measured using multi-frequency electrical impedance myography (MFEIM), focusing on changes brought on by disease. This paper addresses two requirements which must be met if the method is to qualify for clinical use. First, the extracted parameters must be reproducible over long time periods such as those involved in the treatment of muscular disease, and second, differences amongst normal subjects should be attributable to known differences in the properties of healthy muscle. It applies the method to five muscle groups in 62 healthy subjects, closely following the procedure used earlier for the diseased subjects. Test–retest comparisons show that parameters are reproducible at levels from 6 to 16% (depending on the parameter) over time spans of up to 267 days, levels far below the changes occurring in serious disease. Also, variations with age, gender and muscle location are found to be consistent with established expectations for healthy muscle tissue. We conclude that the combination of MFEIM measurements and five-element circuit analysis genuinely reflects properties of muscle and is reliable enough to recommend its use in following neuromuscular disease. (paper)

  16. Reproducibility analysis of measurements with a mechanical semiautomatic eye model for evaluation of intraocular lenses

    Science.gov (United States)

    Rank, Elisabet; Traxler, Lukas; Bayer, Natascha; Reutterer, Bernd; Lux, Kirsten; Drauschke, Andreas

    2014-03-01

    Mechanical eye models are used to validate ex vivo the optical quality of intraocular lenses (IOLs). The quality measurement and test instructions for IOLs are defined in the ISO 11979-2. However, it was mentioned in literature that these test instructions could lead to inaccurate measurements in case of some modern IOL designs. Reproducibility of alignment and measurement processes are presented, performed with a semiautomatic mechanical ex vivo eye model based on optical properties published by Liou and Brennan in the scale 1:1. The cornea, the iris aperture and the IOL itself are separately changeable within the eye model. The adjustment of the IOL can be manipulated by automatic decentration and tilt of the IOL in reference to the optical axis of the whole system, which is defined by the connection line of the central point of the artificial cornea and the iris aperture. With the presented measurement setup two quality criteria are measurable: the modulation transfer function (MTF) and the Strehl ratio. First the reproducibility of the alignment process for definition of initial conditions of the lateral position and tilt in reference to the optical axis of the system is investigated. Furthermore, different IOL holders are tested related to the stable holding of the IOL. The measurement is performed by a before-after comparison of the lens position using a typical decentration and tilt tolerance analysis path. Modulation transfer function MTF and Strehl ratio S before and after this tolerance analysis are compared and requirements for lens holder construction are deduced from the presented results.

  17. Assessment of a climate model to reproduce rainfall variability and extremes over Southern Africa

    Science.gov (United States)

    Williams, C. J. R.; Kniveton, D. R.; Layberry, R.

    2010-01-01

    It is increasingly accepted that any possible climate change will not only have an influence on mean climate but may also significantly alter climatic variability. A change in the distribution and magnitude of extreme rainfall events (associated with changing variability), such as droughts or flooding, may have a far greater impact on human and natural systems than a changing mean. This issue is of particular importance for environmentally vulnerable regions such as southern Africa. The sub-continent is considered especially vulnerable to and ill-equipped (in terms of adaptation) for extreme events, due to a number of factors including extensive poverty, famine, disease and political instability. Rainfall variability and the identification of rainfall extremes is a function of scale, so high spatial and temporal resolution data are preferred to identify extreme events and accurately predict future variability. The majority of previous climate model verification studies have compared model output with observational data at monthly timescales. In this research, the assessment of ability of a state of the art climate model to simulate climate at daily timescales is carried out using satellite-derived rainfall data from the Microwave Infrared Rainfall Algorithm (MIRA). This dataset covers the period from 1993 to 2002 and the whole of southern Africa at a spatial resolution of 0.1° longitude/latitude. This paper concentrates primarily on the ability of the model to simulate the spatial and temporal patterns of present-day rainfall variability over southern Africa and is not intended to discuss possible future changes in climate as these have been documented elsewhere. Simulations of current climate from the UK Meteorological Office Hadley Centre's climate model, in both regional and global mode, are firstly compared to the MIRA dataset at daily timescales. Secondly, the ability of the model to reproduce daily rainfall extremes is assessed, again by a comparison with

  18. Why are models unable to reproduce multi-decadal trends in lower tropospheric baseline ozone levels?

    Science.gov (United States)

    Hu, L.; Liu, J.; Mickley, L. J.; Strahan, S. E.; Steenrod, S.

    2017-12-01

    Assessments of tropospheric ozone radiative forcing rely on accurate model simulations. Parrish et al (2014) found that three chemistry-climate models (CCMs) overestimate present-day O3 mixing ratios and capture only 50% of the observed O3 increase over the last five decades at 12 baseline sites in the northern mid-latitudes, indicating large uncertainties in our understanding of the ozone trends and their implications for radiative forcing. Here we present comparisons of outputs from two chemical transport models (CTMs) - GEOS-Chem and the Global Modeling Initiative model - with O3 observations from the same sites and from the global ozonesonde network. Both CTMs are driven by reanalysis meteorological data (MERRA or MERRA2) and thus are expected to be different in atmospheric transport processes relative to those freely running CCMs. We test whether recent model developments leading to more active ozone chemistry affect the computed ozone sensitivity to perturbations in emissions. Preliminary results suggest these CTMs can reproduce present-day ozone levels but fail to capture the multi-decadal trend since 1980. Both models yield widespread overpredictions of free tropospheric ozone in the 1980s. Sensitivity studies in GEOS-Chem suggest that the model estimate of natural background ozone is too high. We discuss factors that contribute to the variability and trends of tropospheric ozone over the last 30 years, with a focus on intermodel differences in spatial resolution and in the representation of stratospheric chemistry, stratosphere-troposphere exchange, halogen chemistry, and biogenic VOC emissions and chemistry. We also discuss uncertainty in the historical emission inventories used in models, and how these affect the simulated ozone trends.

  19. A stable and reproducible human blood-brain barrier model derived from hematopoietic stem cells.

    Directory of Open Access Journals (Sweden)

    Romeo Cecchelli

    Full Text Available The human blood brain barrier (BBB is a selective barrier formed by human brain endothelial cells (hBECs, which is important to ensure adequate neuronal function and protect the central nervous system (CNS from disease. The development of human in vitro BBB models is thus of utmost importance for drug discovery programs related to CNS diseases. Here, we describe a method to generate a human BBB model using cord blood-derived hematopoietic stem cells. The cells were initially differentiated into ECs followed by the induction of BBB properties by co-culture with pericytes. The brain-like endothelial cells (BLECs express tight junctions and transporters typically observed in brain endothelium and maintain expression of most in vivo BBB properties for at least 20 days. The model is very reproducible since it can be generated from stem cells isolated from different donors and in different laboratories, and could be used to predict CNS distribution of compounds in human. Finally, we provide evidence that Wnt/β-catenin signaling pathway mediates in part the BBB inductive properties of pericytes.

  20. Stochastic model of financial markets reproducing scaling and memory in volatility return intervals

    Science.gov (United States)

    Gontis, V.; Havlin, S.; Kononovicius, A.; Podobnik, B.; Stanley, H. E.

    2016-11-01

    We investigate the volatility return intervals in the NYSE and FOREX markets. We explain previous empirical findings using a model based on the interacting agent hypothesis instead of the widely-used efficient market hypothesis. We derive macroscopic equations based on the microscopic herding interactions of agents and find that they are able to reproduce various stylized facts of different markets and different assets with the same set of model parameters. We show that the power-law properties and the scaling of return intervals and other financial variables have a similar origin and could be a result of a general class of non-linear stochastic differential equations derived from a master equation of an agent system that is coupled by herding interactions. Specifically, we find that this approach enables us to recover the volatility return interval statistics as well as volatility probability and spectral densities for the NYSE and FOREX markets, for different assets, and for different time-scales. We find also that the historical S&P500 monthly series exhibits the same volatility return interval properties recovered by our proposed model. Our statistical results suggest that human herding is so strong that it persists even when other evolving fluctuations perturbate the financial system.

  1. Modeling arson - An exercise in qualitative model building

    Science.gov (United States)

    Heineke, J. M.

    1975-01-01

    A detailed example is given of the role of von Neumann and Morgenstern's 1944 'expected utility theorem' (in the theory of games and economic behavior) in qualitative model building. Specifically, an arsonist's decision as to the amount of time to allocate to arson and related activities is modeled, and the responsiveness of this time allocation to changes in various policy parameters is examined. Both the activity modeled and the method of presentation are intended to provide an introduction to the scope and power of the expected utility theorem in modeling situations of 'choice under uncertainty'. The robustness of such a model is shown to vary inversely with the number of preference restrictions used in the analysis. The fewer the restrictions, the wider is the class of agents to which the model is applicable, and accordingly more confidence is put in the derived results. A methodological discussion on modeling human behavior is included.

  2. How well do CMIP5 Climate Models Reproduce the Hydrologic Cycle of the Colorado River Basin?

    Science.gov (United States)

    Gautam, J.; Mascaro, G.

    2017-12-01

    The Colorado River, which is the primary source of water for nearly 40 million people in the arid Southwestern states of the United States, has been experiencing an extended drought since 2000, which has led to a significant reduction in water supply. As the water demands increase, one of the major challenges for water management in the region has been the quantification of uncertainties associated with streamflow predictions in the Colorado River Basin (CRB) under potential changes of future climate. Hence, testing the reliability of model predictions in the CRB is critical in addressing this challenge. In this study, we evaluated the performances of 17 General Circulation Models (GCMs) from the Coupled Model Intercomparison Project Phase Five (CMIP5) and 4 Regional Climate Models (RCMs) in reproducing the statistical properties of the hydrologic cycle in the CRB. We evaluated the water balance components at four nested sub-basins along with the inter-annual and intra-annual changes of precipitation (P), evaporation (E), runoff (R) and temperature (T) from 1979 to 2005. Most of the models captured the net water balance fairly well in the most-upstream basin but simulated a weak hydrological cycle in the evaporation channel at the downstream locations. The simulated monthly variability of P had different patterns, with correlation coefficients ranging from -0.6 to 0.8 depending on the sub-basin and the models from same parent institution clustering together. Apart from the most-upstream sub-basin where the models were mainly characterized by a negative seasonal bias in SON (of up to -50%), most of them had a positive bias in all seasons (of up to +260%) in the other three sub-basins. The models, however, captured the monthly variability of T well at all sites with small inter-model variabilities and a relatively similar range of bias (-7 °C to +5 °C) across all seasons. Mann-Kendall test was applied to the annual P and T time-series where majority of the models

  3. Synaptic augmentation in a cortical circuit model reproduces serial dependence in visual working memory.

    Directory of Open Access Journals (Sweden)

    Daniel P Bliss

    Full Text Available Recent work has established that visual working memory is subject to serial dependence: current information in memory blends with that from the recent past as a function of their similarity. This tuned temporal smoothing likely promotes the stability of memory in the face of noise and occlusion. Serial dependence accumulates over several seconds in memory and deteriorates with increased separation between trials. While this phenomenon has been extensively characterized in behavior, its neural mechanism is unknown. In the present study, we investigate the circuit-level origins of serial dependence in a biophysical model of cortex. We explore two distinct kinds of mechanisms: stable persistent activity during the memory delay period and dynamic "activity-silent" synaptic plasticity. We find that networks endowed with both strong reverberation to support persistent activity and dynamic synapses can closely reproduce behavioral serial dependence. Specifically, elevated activity drives synaptic augmentation, which biases activity on the subsequent trial, giving rise to a spatiotemporally tuned shift in the population response. Our hybrid neural model is a theoretical advance beyond abstract mathematical characterizations, offers testable hypotheses for physiological research, and demonstrates the power of biological insights to provide a quantitative explanation of human behavior.

  4. Fast bootstrapping and permutation testing for assessing reproducibility and interpretability of multivariate fMRI decoding models.

    Directory of Open Access Journals (Sweden)

    Bryan R Conroy

    Full Text Available Multivariate decoding models are increasingly being applied to functional magnetic imaging (fMRI data to interpret the distributed neural activity in the human brain. These models are typically formulated to optimize an objective function that maximizes decoding accuracy. For decoding models trained on full-brain data, this can result in multiple models that yield the same classification accuracy, though some may be more reproducible than others--i.e. small changes to the training set may result in very different voxels being selected. This issue of reproducibility can be partially controlled by regularizing the decoding model. Regularization, along with the cross-validation used to estimate decoding accuracy, typically requires retraining many (often on the order of thousands of related decoding models. In this paper we describe an approach that uses a combination of bootstrapping and permutation testing to construct both a measure of cross-validated prediction accuracy and model reproducibility of the learned brain maps. This requires re-training our classification method on many re-sampled versions of the fMRI data. Given the size of fMRI datasets, this is normally a time-consuming process. Our approach leverages an algorithm called fast simultaneous training of generalized linear models (FaSTGLZ to create a family of classifiers in the space of accuracy vs. reproducibility. The convex hull of this family of classifiers can be used to identify a subset of Pareto optimal classifiers, with a single-optimal classifier selectable based on the relative cost of accuracy vs. reproducibility. We demonstrate our approach using full-brain analysis of elastic-net classifiers trained to discriminate stimulus type in an auditory and visual oddball event-related fMRI design. Our approach and results argue for a computational approach to fMRI decoding models in which the value of the interpretation of the decoding model ultimately depends upon optimizing a

  5. Rainfall variability and extremes over southern Africa: Assessment of a climate model to reproduce daily extremes

    Science.gov (United States)

    Williams, C. J. R.; Kniveton, D. R.; Layberry, R.

    2009-04-01

    It is increasingly accepted that that any possible climate change will not only have an influence on mean climate but may also significantly alter climatic variability. A change in the distribution and magnitude of extreme rainfall events (associated with changing variability), such as droughts or flooding, may have a far greater impact on human and natural systems than a changing mean. This issue is of particular importance for environmentally vulnerable regions such as southern Africa. The subcontinent is considered especially vulnerable to and ill-equipped (in terms of adaptation) for extreme events, due to a number of factors including extensive poverty, famine, disease and political instability. Rainfall variability and the identification of rainfall extremes is a function of scale, so high spatial and temporal resolution data are preferred to identify extreme events and accurately predict future variability. The majority of previous climate model verification studies have compared model output with observational data at monthly timescales. In this research, the assessment of ability of a state of the art climate model to simulate climate at daily timescales is carried out using satellite derived rainfall data from the Microwave Infra-Red Algorithm (MIRA). This dataset covers the period from 1993-2002 and the whole of southern Africa at a spatial resolution of 0.1 degree longitude/latitude. The ability of a climate model to simulate current climate provides some indication of how much confidence can be applied to its future predictions. In this paper, simulations of current climate from the UK Meteorological Office Hadley Centre's climate model, in both regional and global mode, are firstly compared to the MIRA dataset at daily timescales. This concentrates primarily on the ability of the model to simulate the spatial and temporal patterns of rainfall variability over southern Africa. Secondly, the ability of the model to reproduce daily rainfall extremes will

  6. A methodology for acquiring qualitative knowledge for probabilistic graphical models

    DEFF Research Database (Denmark)

    Kjærulff, Uffe Bro; Madsen, Anders L.

    2004-01-01

    We present a practical and general methodology that simplifies the task of acquiring and formulating qualitative knowledge for constructing probabilistic graphical models (PGMs). The methodology efficiently captures and communicates expert knowledge, and has significantly eased the model developm......We present a practical and general methodology that simplifies the task of acquiring and formulating qualitative knowledge for constructing probabilistic graphical models (PGMs). The methodology efficiently captures and communicates expert knowledge, and has significantly eased the model...

  7. Cross-species analysis of gene expression in non-model mammals: reproducibility of hybridization on high density oligonucleotide microarrays

    Directory of Open Access Journals (Sweden)

    Pita-Thomas Wolfgang

    2007-04-01

    Full Text Available Abstract Background Gene expression profiles of non-model mammals may provide valuable data for biomedical and evolutionary studies. However, due to lack of sequence information of other species, DNA microarrays are currently restricted to humans and a few model species. This limitation may be overcome by using arrays developed for a given species to analyse gene expression in a related one, an approach known as "cross-species analysis". In spite of its potential usefulness, the accuracy and reproducibility of the gene expression measures obtained in this way are still open to doubt. The present study examines whether or not hybridization values from cross-species analyses are as reproducible as those from same-species analyses when using Affymetrix oligonucleotide microarrays. Results The reproducibility of the probe data obtained hybridizing deer, Old-World primates, and human RNA samples to Affymetrix human GeneChip® U133 Plus 2.0 was compared. The results show that cross-species hybridization affected neither the distribution of the hybridization reproducibility among different categories, nor the reproducibility values of the individual probes. Our analyses also show that a 0.5% of the probes analysed in the U133 plus 2.0 GeneChip are significantly associated to un-reproducible hybridizations. Such probes-called in the text un-reproducible probe sequences- do not increase in number in cross-species analyses. Conclusion Our study demonstrates that cross-species analyses do not significantly affect hybridization reproducibility of GeneChips, at least within the range of the mammal species analysed here. The differences in reproducibility between same-species and cross-species analyses observed in previous studies were probably caused by the analytical methods used to calculate the gene expression measures. Together with previous observations on the accuracy of GeneChips for cross-species analysis, our analyses demonstrate that cross

  8. Model for a reproducible curriculum infrastructure to provide international nurse anesthesia continuing education.

    Science.gov (United States)

    Collins, Shawn Bryant

    2011-12-01

    There are no set standards for nurse anesthesia education in developing countries, yet one of the keys to the standards in global professional practice is competency assurance for individuals. Nurse anesthetists in developing countries have difficulty obtaining educational materials. These difficulties include, but are not limited to, financial constraints, lack of anesthesia textbooks, and distance from educational sites. There is increasing evidence that the application of knowledge in developing countries is failing. One reason is that many anesthetists in developing countries are trained for considerably less than acceptable time periods and are often supervised by poorly trained practitioners, who then pass on less-than-desirable practice skills, thus exacerbating difficulties. Sustainability of development can come only through anesthetists who are both well trained and able to pass on their training to others. The international nurse anesthesia continuing education project was developed in response to the difficulty that nurse anesthetists in developing countries face in accessing continuing education. The purpose of this project was to develop a nonprofit, volunteer-based model for providing nurse anesthesia continuing education that can be reproduced and used in any developing country.

  9. Composite model to reproduce the mechanical behaviour of methane hydrate bearing soils

    Science.gov (United States)

    De la Fuente, Maria

    2016-04-01

    Methane hydrate bearing sediments (MHBS) are naturally-occurring materials containing different components in the pores that may suffer phase changes under relative small temperature and pressure variations for conditions typically prevailing a few hundreds of meters below sea level. Their modelling needs to account for heat and mass balance equations of the different components, and several strategies already exist to combine them (e.g., Rutqvist & Moridis, 2009; Sánchez et al. 2014). These equations have to be completed by restrictions and constitutive laws reproducing the phenomenology of heat and fluid flows, phase change conditions and mechanical response. While the formulation of the non-mechanical laws generally includes explicitly the mass fraction of methane in each phase, which allows for a natural update of parameters during phase changes, mechanical laws are, in most cases, stated for the whole solid skeleton (Uchida et al., 2012; Soga et al. 2006). In this paper, a mechanical model is proposed to cope with the response of MHBS. It is based on a composite approach that allows defining the thermo-hydro-mechanical response of mineral skeleton and solid hydrates independently. The global stress-strain-temperature response of the solid phase (grains + hydrate) is then obtained by combining both responses according to energy principle following the work by Pinyol et al. (2007). In this way, dissociation of MH can be assessed on the basis of the stress state and temperature prevailing locally within the hydrate component. Besides, its structuring effect is naturally accounted for by the model according to patterns of MH inclusions within soil pores. This paper describes the fundamental hypothesis behind the model and its formulation. Its performance is assessed by comparison with laboratory data presented in the literature. An analysis of MHBS response to several stress-temperature paths representing potential field cases is finally presented. References

  10. Qualitative models of magnetic field accelerated propagation in a plasma due to the Hall effect

    International Nuclear Information System (INIS)

    Kukushkin, A.B.; Cherepanov, K.V.

    2000-01-01

    Two qualitatively new models of accelerated magnetic field propagation (relative to normal diffusion) in a plasma due to the Hall effect are developed within the frames of the electron magnetic hydrodynamics. The first model is based on a simple hydrodynamic approach, which, in particular, reproduces the number of known theoretical results. The second one makes it possible to obtain exact analytical description of the basic characteristics of the magnetic field accelerated propagation in a inhomogeneous iso-thermic plasma, namely, the magnetic field front and its effective width [ru

  11. Qualitative modelling macroeconomics indicators for prediction of progress branch

    Directory of Open Access Journals (Sweden)

    Jiří Luňáček

    2010-01-01

    Full Text Available A qualitative modelling philosophy has been developed in an effort to produce a general and reasonably unified common sense approach to the modelling of unique, complex and unsteady state systems. Economics, Ecology, Sociology and Politics are sciences, which study such systems. An integration of sub models from those sciences into supermodels is inevitable if realistic decision making tasks are analysed. Therefore conventional formal tools (e.g. statistics cannot be correctly applied because of lack of information. Qualitative variables are quantified using three values only – positive (increasing, zero (constant and negative (decreasing. Knowledge items of qualitative nature (e.g. if productivity goes up then profit does not decrease are often the only available information. The classical quantitative tools cannot deal with such information items. However, qualitative models can absorb shallow qualitative knowledge and generate all possible scenarios i.e. qualitative solutions. The complete list of scenarios guarantees that any analysis (decision making based on it does not ignore any promising solution. The case study of oil related macro economical risks is presented in details (15 variables e.g. Inflation, Corruption, 14 qualitative relations among the variables. No a priory know­ledge of qualitative analysis is required.

  12. Can Computational Sediment Transport Models Reproduce the Observed Variability of Channel Networks in Modern Deltas?

    Science.gov (United States)

    Nesvold, E.; Mukerji, T.

    2017-12-01

    River deltas display complex channel networks that can be characterized through the framework of graph theory, as shown by Tejedor et al. (2015). Deltaic patterns may also be useful in a Bayesian approach to uncertainty quantification of the subsurface, but this requires a prior distribution of the networks of ancient deltas. By considering subaerial deltas, one can at least obtain a snapshot in time of the channel network spectrum across deltas. In this study, the directed graph structure is semi-automatically extracted from satellite imagery using techniques from statistical processing and machine learning. Once the network is labeled with vertices and edges, spatial trends and width and sinuosity distributions can also be found easily. Since imagery is inherently 2D, computational sediment transport models can serve as a link between 2D network structure and 3D depositional elements; the numerous empirical rules and parameters built into such models makes it necessary to validate the output with field data. For this purpose we have used a set of 110 modern deltas, with average water discharge ranging from 10 - 200,000 m3/s, as a benchmark for natural variability. Both graph theoretic and more general distributions are established. A key question is whether it is possible to reproduce this deltaic network spectrum with computational models. Delft3D was used to solve the shallow water equations coupled with sediment transport. The experimental setup was relatively simple; incoming channelized flow onto a tilted plane, with varying wave and tidal energy, sediment types and grain size distributions, river discharge and a few other input parameters. Each realization was run until a delta had fully developed: between 50 and 500 years (with a morphology acceleration factor). It is shown that input parameters should not be sampled independently from the natural ranges, since this may result in deltaic output that falls well outside the natural spectrum. Since we are

  13. Conceptual model suitability for reproducing preferential flow paths in waste rock piles

    Science.gov (United States)

    Broda, S.; Blessent, D.; Aubertin, M.

    2012-12-01

    Waste rocks are typically deposited on mining sites forming waste rock piles (WRP). Acid mine drainage (AMD) or contaminated neutral drainage (CND) with metal leaching from the sulphidic minerals adversely impact soil and water composition on and beyond the mining sites. The deposition method and the highly heterogeneous hydrogeological and geochemical properties of waste rock have a major impact on water and oxygen movement and pore water pressure distribution in the WRP, controlling AMD/CND production. However, the prediction and interpretation of water distribution in WRP is a challenging problem and many attempted numerical investigations of short and long term forecasts were found unreliable. Various forms of unsaturated localized preferential flow processes have been identified, for instance flow in macropores and fractures, heterogeneity-driven and gravity-driven unstable flow, with local hydraulic conductivities reaching several dozen meters per day. Such phenomena have been entirely neglected in numerical WRP modelling and are unattainable with the classical equivalent porous media conceptual approach typically used in this field. An additional complicating circumstance is the unknown location of macropores and fractures a priori. In this study, modeling techniques originally designed for massive fractured rock aquifers are applied. The properties of the waste rock material, found at the Tio mine at Havre Saint-Pierre, Québec (Canada), used in this modelling study were retrieved from laboratory permeability and water retention tests. These column tests were reproduced with the numerical 3D fully-integrated surface/subsurface flow model HydroGeoSphere, where material heterogeneity is represented by means of i) the dual continuum approach, ii) discrete fractures, and iii) a stochastic facies distribution framework using TPROGS. Comparisons with measured pore water pressures, tracer concentrations and exiting water volumes allowed defining limits and

  14. SDG and qualitative trend based model multiple scale validation

    Science.gov (United States)

    Gao, Dong; Xu, Xin; Yin, Jianjin; Zhang, Hongyu; Zhang, Beike

    2017-09-01

    Verification, Validation and Accreditation (VV&A) is key technology of simulation and modelling. For the traditional model validation methods, the completeness is weak; it is carried out in one scale; it depends on human experience. The SDG (Signed Directed Graph) and qualitative trend based multiple scale validation is proposed. First the SDG model is built and qualitative trends are added to the model. And then complete testing scenarios are produced by positive inference. The multiple scale validation is carried out by comparing the testing scenarios with outputs of simulation model in different scales. Finally, the effectiveness is proved by carrying out validation for a reactor model.

  15. A novel, comprehensive, and reproducible porcine model for determining the timing of bruises in forensic pathology

    DEFF Research Database (Denmark)

    Barington, Kristiane; Jensen, Henrik Elvang

    2016-01-01

    in order to identify gross and histological parameters that may be useful in determining the age of a bruise. Methods The mechanical device was able to apply a single reproducible stroke with a plastic tube that was equivalent to being struck by a man. In each of 10 anesthetized pigs, four strokes...

  16. Pharmacokinetic Modelling to Predict FVIII:C Response to Desmopressin and Its Reproducibility in Nonsevere Haemophilia A Patients.

    Science.gov (United States)

    Schütte, Lisette M; van Hest, Reinier M; Stoof, Sara C M; Leebeek, Frank W G; Cnossen, Marjon H; Kruip, Marieke J H A; Mathôt, Ron A A

    2018-04-01

     Nonsevere haemophilia A (HA) patients can be treated with desmopressin. Response of factor VIII activity (FVIII:C) differs between patients and is difficult to predict.  Our aims were to describe FVIII:C response after desmopressin and its reproducibility by population pharmacokinetic (PK) modelling.  Retrospective data of 128 nonsevere HA patients (age 7-75 years) receiving an intravenous or intranasal dose of desmopressin were used. PK modelling of FVIII:C was performed by nonlinear mixed effect modelling. Reproducibility of FVIII:C response was defined as less than 25% difference in peak FVIII:C between administrations.  A total of 623 FVIII:C measurements from 142 desmopressin administrations were available; 14 patients had received two administrations at different occasions. The FVIII:C time profile was best described by a two-compartment model with first-order absorption and elimination. Interindividual variability of the estimated baseline FVIII:C, central volume of distribution and clearance were 37, 43 and 50%, respectively. The most recently measured FVIII:C (FVIII-recent) was significantly associated with FVIII:C response to desmopressin ( p  C increase of 0.47 IU/mL (median, interquartile range: 0.32-0.65 IU/mL, n  = 142). C response was reproducible in 6 out of 14 patients receiving two desmopressin administrations.  FVIII:C response to desmopressin in nonsevere HA patients was adequately described by a population PK model. Large variability in FVIII:C response was observed, which could only partially be explained by FVIII-recent. C response was not reproducible in a small subset of patients. Therefore, monitoring FVIII:C around surgeries or bleeding might be considered. Research is needed to study this further. Schattauer Stuttgart.

  17. Graphical means for inspecting qualitative models of system behaviour

    NARCIS (Netherlands)

    Bouwer, A.; Bredeweg, B.

    2010-01-01

    This article presents the design and evaluation of a tool for inspecting conceptual models of system behaviour. The basis for this research is the Garp framework for qualitative simulation. This framework includes modelling primitives, such as entities, quantities and causal dependencies, which are

  18. Automated Qualitative Modeling of Dynamic Physical Systems

    Science.gov (United States)

    1993-01-01

    Resnick, Naomi Ribner, Ruth Schonfeld, Re- becca Simmons, Cindy Wible, and especially David Clemens, Nomi Harris, Michele Popper , Karen Sarachik, and...describe a part of a system by using a component name, such as "mo- tor." MM accepts both geometric and component descriptions, and allows t, e two...not a scientific discovery program along the lines of, say, BACON [201, which could also be said to be constructing models of systems. Thus the first

  19. Qualitative model of a plasma photoelectric converter

    Science.gov (United States)

    Gorbunov, N. A.; Flamant, G.

    2009-01-01

    A converter of focused optical radiation into electric current is considered on the basis of the photovoltaic effect in plasmas. The converter model is based on analysis of asymmetric spatial distributions of charge particle number density and ambipolar potential in the photoplasma produced by external optical radiation focused in a heat pipe filled with a mixture of alkali vapor and a heavy inert gas. Energy balance in the plasma photoelectric converter is analyzed. The conditions in which the external radiation energy is effectively absorbed in the converter are indicated. The plasma parameters for which the energy of absorbed optical radiation is mainly spent on sustaining the ambipolar field in the plasma are determined. It is shown that the plasma photoelectric converter makes it possible to attain a high conversion efficiency for focused solar radiation.

  20. Quantitative versus qualitative modeling: a complementary approach in ecosystem study.

    Science.gov (United States)

    Bondavalli, C; Favilla, S; Bodini, A

    2009-02-01

    Natural disturbance or human perturbation act upon ecosystems by changing some dynamical parameters of one or more species. Foreseeing these modifications is necessary before embarking on an intervention: predictions may help to assess management options and define hypothesis for interventions. Models become valuable tools for studying and making predictions only when they capture types of interactions and their magnitude. Quantitative models are more precise and specific about a system, but require a large effort in model construction. Because of this very often ecological systems remain only partially specified and one possible approach to their description and analysis comes from qualitative modelling. Qualitative models yield predictions as directions of change in species abundance but in complex systems these predictions are often ambiguous, being the result of opposite actions exerted on the same species by way of multiple pathways of interactions. Again, to avoid such ambiguities one needs to know the intensity of all links in the system. One way to make link magnitude explicit in a way that can be used in qualitative analysis is described in this paper and takes advantage of another type of ecosystem representation: ecological flow networks. These flow diagrams contain the structure, the relative position and the connections between the components of a system, and the quantity of matter flowing along every connection. In this paper it is shown how these ecological flow networks can be used to produce a quantitative model similar to the qualitative counterpart. Analyzed through the apparatus of loop analysis this quantitative model yields predictions that are by no means ambiguous, solving in an elegant way the basic problem of qualitative analysis. The approach adopted in this work is still preliminary and we must be careful in its application.

  1. Intra- and interobserver reliability and intra-catheter reproducibility using frequency domain optical coherence tomography for the evaluation of morphometric stent parameters and qualitative assessment of stent strut coverage

    International Nuclear Information System (INIS)

    Antonsen, Lisbeth; Thayssen, Per; Junker, Anders; Veien, Karsten Tange; Hansen, Henrik Steen; Hansen, Knud Nørregaard; Hougaard, Mikkel; Jensen, Lisette Okkels

    2015-01-01

    Purpose: Frequency-domain optical coherence tomography (FD-OCT) is a high-resolution imaging tool (~ 10–15 μm), which enables near-histological in-vivo images of the coronary vessel wall. The use of the technique is increasing, both for research- and clinical purposes. This study sought to investigate the intra- and interobserver reliability, as well as the intra-catheter reproducibility of quantitative FD-OCT-assessment of morphometric stent parameters and qualitative FD-OCT-evaluation of strut coverage in 10 randomly selected 6-month follow-up Nobori® biolimus-eluting stents (N-BESs). Methods: Ten N-BESs (213 cross sectional areas (CSAs) and 1897 struts) imaged with OCT 6 months post-implantation were randomly selected and analyzed by 2 experienced analysts, and the same 10 N-BESs were analyzed by one of the analysts 3 months later. Further, 2 consecutive pullbacks randomly performed in another 10 N-BESs (219 CSAs and 1860 struts) were independently assessed by one of the analysts. Results: The intraobserver variability with regard to relative difference of mean luminal area and mean stent area at the CSA-level was very low: 0.1% ± 1.4% and 0.5% ± 3.2%. Interobserver variability also proved to be low: − 2.1% ± 3.3% and 2.1% ± 4.6%, and moreover, very restricted intra-catheter variation was observed: 0.02% ± 6.8% and − 0.18% ± 5.2%. The intraobserver-, interobserver- and intra-catheter reliability for the qualitative evaluation of strut coverage was found to be: kappa (κ) = 0.91 (95% confidence interval (CI): 0.88–0.93, p < 0.01), κ = 0.88 (95% CI: 0.85–0.91, p < 0.01), and κ = 0.73 (95% CI: 0.68–0.78, p < 0.01), respectively. Conclusions: FD-OCT is a reproducible and reliable imaging tool for quantitative evaluation of stented coronary segments, and for qualitative assessment of strut coverage. - Highlights: • Frequency-domain optical coherence tomography (FD-OCT) is increasingly adopted in the catherization laboratories. • This

  2. Qualitative mechanism models and the rationalization of procedures

    Science.gov (United States)

    Farley, Arthur M.

    1989-01-01

    A qualitative, cluster-based approach to the representation of hydraulic systems is described and its potential for generating and explaining procedures is demonstrated. Many ideas are formalized and implemented as part of an interactive, computer-based system. The system allows for designing, displaying, and reasoning about hydraulic systems. The interactive system has an interface consisting of three windows: a design/control window, a cluster window, and a diagnosis/plan window. A qualitative mechanism model for the ORS (Orbital Refueling System) is presented to coordinate with ongoing research on this system being conducted at NASA Ames Research Center.

  3. From qualitative reasoning models to Bayesian-based learner modeling

    NARCIS (Netherlands)

    Milošević, U.; Bredeweg, B.; de Kleer, J.; Forbus, K.D.

    2010-01-01

    Assessing the knowledge of a student is a fundamental part of intelligent learning environments. We present a Bayesian network based approach to dealing with uncertainty when estimating a learner’s state of knowledge in the context of Qualitative Reasoning (QR). A proposal for a global architecture

  4. A novel porcine model of ataxia telangiectasia reproduces neurological features and motor deficits of human disease.

    Science.gov (United States)

    Beraldi, Rosanna; Chan, Chun-Hung; Rogers, Christopher S; Kovács, Attila D; Meyerholz, David K; Trantzas, Constantin; Lambertz, Allyn M; Darbro, Benjamin W; Weber, Krystal L; White, Katherine A M; Rheeden, Richard V; Kruer, Michael C; Dacken, Brian A; Wang, Xiao-Jun; Davis, Bryan T; Rohret, Judy A; Struzynski, Jason T; Rohret, Frank A; Weimer, Jill M; Pearce, David A

    2015-11-15

    Ataxia telangiectasia (AT) is a progressive multisystem disorder caused by mutations in the AT-mutated (ATM) gene. AT is a neurodegenerative disease primarily characterized by cerebellar degeneration in children leading to motor impairment. The disease progresses with other clinical manifestations including oculocutaneous telangiectasia, immune disorders, increased susceptibly to cancer and respiratory infections. Although genetic investigations and physiological models have established the linkage of ATM with AT onset, the mechanisms linking ATM to neurodegeneration remain undetermined, hindering therapeutic development. Several murine models of AT have been successfully generated showing some of the clinical manifestations of the disease, however they do not fully recapitulate the hallmark neurological phenotype, thus highlighting the need for a more suitable animal model. We engineered a novel porcine model of AT to better phenocopy the disease and bridge the gap between human and current animal models. The initial characterization of AT pigs revealed early cerebellar lesions including loss of Purkinje cells (PCs) and altered cytoarchitecture suggesting a developmental etiology for AT and could advocate for early therapies for AT patients. In addition, similar to patients, AT pigs show growth retardation and develop motor deficit phenotypes. By using the porcine system to model human AT, we established the first animal model showing PC loss and motor features of the human disease. The novel AT pig provides new opportunities to unmask functions and roles of ATM in AT disease and in physiological conditions. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  5. A novel porcine model of ataxia telangiectasia reproduces neurological features and motor deficits of human disease

    Science.gov (United States)

    Beraldi, Rosanna; Chan, Chun-Hung; Rogers, Christopher S.; Kovács, Attila D.; Meyerholz, David K.; Trantzas, Constantin; Lambertz, Allyn M.; Darbro, Benjamin W.; Weber, Krystal L.; White, Katherine A.M.; Rheeden, Richard V.; Kruer, Michael C.; Dacken, Brian A.; Wang, Xiao-Jun; Davis, Bryan T.; Rohret, Judy A.; Struzynski, Jason T.; Rohret, Frank A.; Weimer, Jill M.; Pearce, David A.

    2015-01-01

    Ataxia telangiectasia (AT) is a progressive multisystem disorder caused by mutations in the AT-mutated (ATM) gene. AT is a neurodegenerative disease primarily characterized by cerebellar degeneration in children leading to motor impairment. The disease progresses with other clinical manifestations including oculocutaneous telangiectasia, immune disorders, increased susceptibly to cancer and respiratory infections. Although genetic investigations and physiological models have established the linkage of ATM with AT onset, the mechanisms linking ATM to neurodegeneration remain undetermined, hindering therapeutic development. Several murine models of AT have been successfully generated showing some of the clinical manifestations of the disease, however they do not fully recapitulate the hallmark neurological phenotype, thus highlighting the need for a more suitable animal model. We engineered a novel porcine model of AT to better phenocopy the disease and bridge the gap between human and current animal models. The initial characterization of AT pigs revealed early cerebellar lesions including loss of Purkinje cells (PCs) and altered cytoarchitecture suggesting a developmental etiology for AT and could advocate for early therapies for AT patients. In addition, similar to patients, AT pigs show growth retardation and develop motor deficit phenotypes. By using the porcine system to model human AT, we established the first animal model showing PC loss and motor features of the human disease. The novel AT pig provides new opportunities to unmask functions and roles of ATM in AT disease and in physiological conditions. PMID:26374845

  6. Validation of EURO-CORDEX regional climate models in reproducing the variability of precipitation extremes in Romania

    Science.gov (United States)

    Dumitrescu, Alexandru; Busuioc, Aristita

    2016-04-01

    EURO-CORDEX is the European branch of the international CORDEX initiative that aims to provide improved regional climate change projections for Europe. The main objective of this paper is to document the performance of the individual models in reproducing the variability of precipitation extremes in Romania. Here three EURO-CORDEX regional climate models (RCMs) ensemble (scenario RCP4.5) are analysed and inter-compared: DMI-HIRHAM5, KNMI-RACMO2.2 and MPI-REMO. Compared to previous studies, when the RCM validation regarding the Romanian climate has mainly been made on mean state and at station scale, a more quantitative approach of precipitation extremes is proposed. In this respect, to have a more reliable comparison with observation, a high resolution daily precipitation gridded data set was used as observational reference (CLIMHYDEX project). The comparison between the RCM outputs and observed grid point values has been made by calculating three extremes precipitation indices, recommended by the Expert Team on Climate Change Detection Indices (ETCCDI), for the 1976-2005 period: R10MM, annual count of days when precipitation ≥10mm; RX5DAY, annual maximum 5-day precipitation and R95P%, precipitation fraction of annual total precipitation due to daily precipitation > 95th percentile. The RCMs capability to reproduce the mean state for these variables, as well as the main modes of their spatial variability (given by the first three EOF patterns), are analysed. The investigation confirms the ability of RCMs to simulate the main features of the precipitation extreme variability over Romania, but some deficiencies in reproducing of their regional characteristics were found (for example, overestimation of the mea state, especially over the extra Carpathian regions). This work has been realised within the research project "Changes in climate extremes and associated impact in hydrological events in Romania" (CLIMHYDEX), code PN II-ID-2011-2-0073, financed by the Romanian

  7. Using a 1-D model to reproduce the diurnal variability of SST

    DEFF Research Database (Denmark)

    Karagali, Ioanna; Høyer, Jacob L.; Donlon, Craig J.

    2017-01-01

    preferred approach to bridge the gap between in situ and remotely sensed measurements and obtain diurnal warming estimates at large spatial scales is modeling of the upper ocean temperature. This study uses the one-dimensional General Ocean Turbulence Model (GOTM) to resolve diurnal signals identified from...... forcing fields and is able to resolve daily SST variability seen both from satellite and in situ measurements. As such, and due to its low computational cost, it is proposed as a candidate model for diurnal variability estimates....

  8. Energy and nutrient deposition and excretion in the reproducing sow: model development and evaluation

    DEFF Research Database (Denmark)

    Hansen, A V; Strathe, A B; Theil, Peter Kappel

    2014-01-01

    was related to predictions of body fat and protein loss from the lactation model. Nitrogen intake, urine N, fecal N, and milk N were predicted with RMSPE as percentage of observed mean of 9.7, 17.9, 10.0, and 7.7%, respectively. The model provided a framework, but more refinements and improvements in accuracy......Air and nutrient emissions from swine operations raise environmental concerns. During the reproduction phase, sows consume and excrete large quantities of nutrients. The objective of this study was to develop a mathematical model to describe energy and nutrient partitioning and predict manure...... excretion and composition and methane emissions on a daily basis. The model was structured to contain gestation and lactation modules, which can be run separately or sequentially, with outputs from the gestation module used as inputs to the lactation module. In the gestating module, energy and protein...

  9. Do on/off time series models reproduce emerging stock market comovements?

    OpenAIRE

    Mohamed el hédi Arouri; Fredj Jawadi

    2011-01-01

    Using nonlinear modeling tools, this study investigates the comovements between the Mexican and the world stock markets over the last three decades. While the previous works only highlight some evidence of comovements, our paper aims to specify the different time-varying links and mechanisms characterizing the Mexican stock market through the comparison of two nonlinear error correction models (NECMs). Our findings point out strong evidence of time-varying and nonlinear mean-reversion and lin...

  10. The Computable Catchment: An executable document for model-data software sharing, reproducibility and interactive visualization

    Science.gov (United States)

    Gil, Y.; Duffy, C.

    2015-12-01

    This paper proposes the concept of a "Computable Catchment" which is used to develop a collaborative platform for watershed modeling and data analysis. The object of the research is a sharable, executable document similar to a pdf, but one that includes documentation of the underlying theoretical concepts, interactive computational/numerical resources, linkage to essential data repositories and the ability for interactive model-data visualization and analysis. The executable document for each catchment is stored in the cloud with automatic provisioning and a unique identifier allowing collaborative model and data enhancements for historical hydroclimatic reconstruction and/or future landuse or climate change scenarios to be easily reconstructed or extended. The Computable Catchment adopts metadata standards for naming all variables in the model and the data. The a-priori or initial data is derived from national data sources for soils, hydrogeology, climate, and land cover available from the www.hydroterre.psu.edu data service (Leonard and Duffy, 2015). The executable document is based on Wolfram CDF or Computable Document Format with an interactive open-source reader accessible by any modern computing platform. The CDF file and contents can be uploaded to a website or simply shared as a normal document maintaining all interactive features of the model and data. The Computable Catchment concept represents one application for Geoscience Papers of the Future representing an extensible document that combines theory, models, data and analysis that are digitally shared, documented and reused among research collaborators, students, educators and decision makers.

  11. "High-precision, reconstructed 3D model" of skull scanned by conebeam CT: Reproducibility verified using CAD/CAM data.

    Science.gov (United States)

    Katsumura, Seiko; Sato, Keita; Ikawa, Tomoko; Yamamura, Keiko; Ando, Eriko; Shigeta, Yuko; Ogawa, Takumi

    2016-01-01

    Computed tomography (CT) scanning has recently been introduced into forensic medicine and dentistry. However, the presence of metal restorations in the dentition can adversely affect the quality of three-dimensional reconstruction from CT scans. In this study, we aimed to evaluate the reproducibility of a "high-precision, reconstructed 3D model" obtained from a conebeam CT scan of dentition, a method that might be particularly helpful in forensic medicine. We took conebeam CT and helical CT images of three dry skulls marked with 47 measuring points; reconstructed three-dimensional images; and measured the distances between the points in the 3D images with a computer-aided design/computer-aided manufacturing (CAD/CAM) marker. We found that in comparison with the helical CT, conebeam CT is capable of reproducing measurements closer to those obtained from the actual samples. In conclusion, our study indicated that the image-reproduction from a conebeam CT scan was more accurate than that from a helical CT scan. Furthermore, the "high-precision reconstructed 3D model" facilitates reliable visualization of full-sized oral and maxillofacial regions in both helical and conebeam CT scans. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  12. A novel porcine model of ataxia telangiectasia reproduces neurological features and motor deficits of human disease

    OpenAIRE

    Beraldi, Rosanna; Chan, Chun-Hung; Rogers, Christopher S.; Kovács, Attila D.; Meyerholz, David K.; Trantzas, Constantin; Lambertz, Allyn M.; Darbro, Benjamin W.; Weber, Krystal L.; White, Katherine A.M.; Rheeden, Richard V.; Kruer, Michael C.; Dacken, Brian A.; Wang, Xiao-Jun; Davis, Bryan T.

    2015-01-01

    Ataxia telangiectasia (AT) is a progressive multisystem disorder caused by mutations in the AT-mutated (ATM) gene. AT is a neurodegenerative disease primarily characterized by cerebellar degeneration in children leading to motor impairment. The disease progresses with other clinical manifestations including oculocutaneous telangiectasia, immune disorders, increased susceptibly to cancer and respiratory infections. Although genetic investigations and physiological models have established the l...

  13. Establishing a Reproducible Hypertrophic Scar following Thermal Injury: A Porcine Model

    Directory of Open Access Journals (Sweden)

    Scott J. Rapp, MD

    2015-02-01

    Conclusions: Deep partial-thickness thermal injury to the back of domestic swine produces an immature hypertrophic scar by 10 weeks following burn with thickness appearing to coincide with the location along the dorsal axis. With minimal pig to pig variation, we describe our technique to provide a testable immature scar model.

  14. Reproducibility of a novel model of murine asthma-like pulmonary inflammation.

    Science.gov (United States)

    McKinley, L; Kim, J; Bolgos, G L; Siddiqui, J; Remick, D G

    2004-05-01

    Sensitization to cockroach allergens (CRA) has been implicated as a major cause of asthma, especially among inner-city populations. Endotoxin from Gram-negative bacteria has also been investigated for its role in attenuating or exacerbating the asthmatic response. We have created a novel model utilizing house dust extract (HDE) containing high levels of both CRA and endotoxin to induce pulmonary inflammation (PI) and airway hyperresponsiveness (AHR). A potential drawback of this model is that the HDE is in limited supply and preparation of new HDE will not contain the exact components of the HDE used to define our model system. The present study involved testing HDEs collected from various homes for their ability to cause PI and AHR. Dust collected from five homes was extracted in phosphate buffered saline overnight. The levels of CRA and endotoxin in the supernatants varied from 7.1 to 49.5 mg/ml of CRA and 1.7-6 micro g/ml of endotoxin in the HDEs. Following immunization and two pulmonary exposures to HDE all five HDEs induced AHR, PI and plasma IgE levels substantially higher than normal mice. This study shows that HDE containing high levels of cockroach allergens and endotoxin collected from different sources can induce an asthma-like response in our murine model.

  15. A computational model incorporating neural stem cell dynamics reproduces glioma incidence across the lifespan in the human population.

    Directory of Open Access Journals (Sweden)

    Roman Bauer

    Full Text Available Glioma is the most common form of primary brain tumor. Demographically, the risk of occurrence increases until old age. Here we present a novel computational model to reproduce the probability of glioma incidence across the lifespan. Previous mathematical models explaining glioma incidence are framed in a rather abstract way, and do not directly relate to empirical findings. To decrease this gap between theory and experimental observations, we incorporate recent data on cellular and molecular factors underlying gliomagenesis. Since evidence implicates the adult neural stem cell as the likely cell-of-origin of glioma, we have incorporated empirically-determined estimates of neural stem cell number, cell division rate, mutation rate and oncogenic potential into our model. We demonstrate that our model yields results which match actual demographic data in the human population. In particular, this model accounts for the observed peak incidence of glioma at approximately 80 years of age, without the need to assert differential susceptibility throughout the population. Overall, our model supports the hypothesis that glioma is caused by randomly-occurring oncogenic mutations within the neural stem cell population. Based on this model, we assess the influence of the (experimentally indicated decrease in the number of neural stem cells and increase of cell division rate during aging. Our model provides multiple testable predictions, and suggests that different temporal sequences of oncogenic mutations can lead to tumorigenesis. Finally, we conclude that four or five oncogenic mutations are sufficient for the formation of glioma.

  16. [Renaissance of training in general surgery in Cambodia: a unique experience or reproducible model].

    Science.gov (United States)

    Dumurgier, C; Baulieux, J

    2005-01-01

    Is the new surgical training program at the University of Phom-Penh, Cambodia a unique experience or can it serve as a model for developing countries? This report describes the encouraging first results of this didactic and hands-on surgical program. Based on their findings the authors recommend not only continuing the program in Phom-Penh but also proposing slightly modified versions to new medical universities not currently offering specialization in surgery.

  17. Evaluation of Nitinol staples for the Lapidus arthrodesis in a reproducible biomechanical model

    Directory of Open Access Journals (Sweden)

    Nicholas Alexander Russell

    2015-12-01

    Full Text Available While the Lapidus procedure is a widely accepted technique for treatment of hallux valgus, the optimal fixation method to maintain joint stability remains controversial. The purpose of this study was to evaluate the biomechanical properties of new Shape Memory Alloy staples arranged in different configurations in a repeatable 1st Tarsometatarsal arthrodesis model. Ten sawbones models of the whole foot (n=5 per group were reconstructed using a single dorsal staple or two staples in a delta configuration. Each construct was mechanically tested in dorsal four-point bending, medial four-point bending, dorsal three-point bending and plantar cantilever bending with the staples activated at 37°C. The peak load, stiffness and plantar gapping were determined for each test. Pressure sensors were used to measure the contact force and area of the joint footprint in each group. There was a significant (p < 0.05 increase in peak load in the two staple constructs compared to the single staple constructs for all testing modalities. Stiffness also increased significantly in all tests except dorsal four-point bending. Pressure sensor readings showed a significantly higher contact force at time zero and contact area following loading in the two staple constructs (p < 0.05. Both groups completely recovered any plantar gapping following unloading and restored their initial contact footprint. The biomechanical integrity and repeatability of the models was demonstrated with no construct failures due to hardware or model breakdown. Shape memory alloy staples provide fixation with the ability to dynamically apply and maintain compression across a simulated arthrodesis following a range of loading conditions.

  18. Can lagrangian models reproduce the migration time of European eel obtained from otolith analysis?

    Science.gov (United States)

    Rodríguez-Díaz, L.; Gómez-Gesteira, M.

    2017-12-01

    European eel can be found at the Bay of Biscay after a long migration across the Atlantic. The duration of migration, which takes place at larval stage, is of primary importance to understand eel ecology and, hence, its survival. This duration is still a controversial matter since it can range from 7 months to > 4 years depending on the method to estimate duration. The minimum migration duration estimated from our lagrangian model is similar to the duration obtained from the microstructure of eel otoliths, which is typically on the order of 7-9 months. The lagrangian model showed to be sensitive to different conditions like spatial and time resolution, release depth, release area and initial distribution. In general, migration showed to be faster when decreasing the depth and increasing the resolution of the model. In average, the fastest migration was obtained when only advective horizontal movement was considered. However, faster migration was even obtained in some cases when locally oriented random migration was taken into account.

  19. Acute multi-sgRNA knockdown of KEOPS complex genes reproduces the microcephaly phenotype of the stable knockout zebrafish model.

    Directory of Open Access Journals (Sweden)

    Tilman Jobst-Schwan

    Full Text Available Until recently, morpholino oligonucleotides have been widely employed in zebrafish as an acute and efficient loss-of-function assay. However, off-target effects and reproducibility issues when compared to stable knockout lines have compromised their further use. Here we employed an acute CRISPR/Cas approach using multiple single guide RNAs targeting simultaneously different positions in two exemplar genes (osgep or tprkb to increase the likelihood of generating mutations on both alleles in the injected F0 generation and to achieve a similar effect as morpholinos but with the reproducibility of stable lines. This multi single guide RNA approach resulted in median likelihoods for at least one mutation on each allele of >99% and sgRNA specific insertion/deletion profiles as revealed by deep-sequencing. Immunoblot showed a significant reduction for Osgep and Tprkb proteins. For both genes, the acute multi-sgRNA knockout recapitulated the microcephaly phenotype and reduction in survival that we observed previously in stable knockout lines, though milder in the acute multi-sgRNA knockout. Finally, we quantify the degree of mutagenesis by deep sequencing, and provide a mathematical model to quantitate the chance for a biallelic loss-of-function mutation. Our findings can be generalized to acute and stable CRISPR/Cas targeting for any zebrafish gene of interest.

  20. An Abstraction Theory for Qualitative Models of Biological Systems

    Directory of Open Access Journals (Sweden)

    Richard Banks

    2010-10-01

    Full Text Available Multi-valued network models are an important qualitative modelling approach used widely by the biological community. In this paper we consider developing an abstraction theory for multi-valued network models that allows the state space of a model to be reduced while preserving key properties of the model. This is important as it aids the analysis and comparison of multi-valued networks and in particular, helps address the well-known problem of state space explosion associated with such analysis. We also consider developing techniques for efficiently identifying abstractions and so provide a basis for the automation of this task. We illustrate the theory and techniques developed by investigating the identification of abstractions for two published MVN models of the lysis-lysogeny switch in the bacteriophage lambda.

  1. Realizing the Living Paper using the ProvONE Model for Reproducible Research

    Science.gov (United States)

    Jones, M. B.; Jones, C. S.; Ludäscher, B.; Missier, P.; Walker, L.; Slaughter, P.; Schildhauer, M.; Cuevas-Vicenttín, V.

    2015-12-01

    Science has advanced through traditional publications that codify research results as a permenant part of the scientific record. But because publications are static and atomic, researchers can only cite and reference a whole work when building on prior work of colleagues. The open source software model has demonstrated a new approach in which strong version control in an open environment can nurture an open ecosystem of software. Developers now commonly fork and extend software giving proper credit, with less repetition, and with confidence in the relationship to original software. Through initiatives like 'Beyond the PDF', an analogous model has been imagined for open science, in which software, data, analyses, and derived products become first class objects within a publishing ecosystem that has evolved to be finer-grained and is realized through a web of linked open data. We have prototyped a Living Paper concept by developing the ProvONE provenance model for scientific workflows, with prototype deployments in DataONE. ProvONE promotes transparency and openness by describing the authenticity, origin, structure, and processing history of research artifacts and by detailing the steps in computational workflows that produce derived products. To realize the Living Paper, we decompose scientific papers into their constituent products and publish these as compound objects in the DataONE federation of archival repositories. Each individual finding and sub-product of a reseach project (such as a derived data table, a workflow or script, a figure, an image, or a finding) can be independently stored, versioned, and cited. ProvONE provenance traces link these fine-grained products within and across versions of a paper, and across related papers that extend an original analysis. This allows for open scientific publishing in which researchers extend and modify findings, creating a dynamic, evolving web of results that collectively represent the scientific enterprise. The

  2. A discrete particle model reproducing collective dynamics of a bee swarm.

    Science.gov (United States)

    Bernardi, Sara; Colombi, Annachiara; Scianna, Marco

    2018-02-01

    In this article, we present a microscopic discrete mathematical model describing collective dynamics of a bee swarm. More specifically, each bee is set to move according to individual strategies and social interactions, the former involving the desire to reach a target destination, the latter accounting for repulsive/attractive stimuli and for alignment processes. The insects tend in fact to remain sufficiently close to the rest of the population, while avoiding collisions, and they are able to track and synchronize their movement to the flight of a given set of neighbors within their visual field. The resulting collective behavior of the bee cloud therefore emerges from non-local short/long-range interactions. Differently from similar approaches present in the literature, we here test different alignment mechanisms (i.e., based either on an Euclidean or on a topological neighborhood metric), which have an impact also on the other social components characterizing insect behavior. A series of numerical realizations then shows the phenomenology of the swarm (in terms of pattern configuration, collective productive movement, and flight synchronization) in different regions of the space of free model parameters (i.e., strength of attractive/repulsive forces, extension of the interaction regions). In this respect, constraints in the possible variations of such coefficients are here given both by reasonable empirical observations and by analytical results on some stability characteristics of the defined pairwise interaction kernels, which have to assure a realistic crystalline configuration of the swarm. An analysis of the effect of unconscious random fluctuations of bee dynamics is also provided. Copyright © 2018 Elsevier Ltd. All rights reserved.

  3. Sprague-Dawley rats are a sustainable and reproducible animal model for induction and study of oral submucous fibrosis

    Directory of Open Access Journals (Sweden)

    Shilpa Maria

    2015-01-01

    Full Text Available Background: Oral submucous fibrosis (OSF is a chronic debilitating disease predominantly affecting the oral cavity and oropharynx. Characteristic histological traits of OSF include epithelial atrophy, inflammation, and a generalized submucosal fibrosis. Several studies and epidemiological surveys provide substantial evidence that areca nut is the main etiological factor for OSF. Hesitance of patients to undergo biopsy procedure together with clinicians becoming increasingly reluctant to take biopsies in cases of OSF has prompted researchers to develop animal models to study the disease process. Materials and Methods: The present study evaluates the efficacy, sustainability, and reproducibility of using Sprague-Dawley (SD rats as a possible model in the induction and progression of OSF. Buccal mucosa of SD rats was injected with areca nut and pan masala solutions on alternate days over a period of 48 weeks. The control group was treated with saline. The influence of areca nut and pan masala on the oral epithelium and connective tissue was evaluated by light microscopy. Results: Oral submucous fibrosis-like lesions were seen in both the areca nut and pan masala treated groups. The histological changes observed included: Atrophic epithelium, partial or complete loss of rete ridges, juxta-epithelial hyalinization, inflammation and accumulation of dense bundles of collagen fibers subepithelially. Conclusions: Histopathological changes in SD rats following treatment with areca nut and pan masala solutions bears a close semblance to that seen in humans with OSF. The SD rats seem to be a cheap and efficient, sustainable and reproducible model for the induction and development of OSF.

  4. The diverse broad-band light-curves of Swift GRBs reproduced with the cannonball model

    CERN Document Server

    Dado, Shlomo; De Rújula, A

    2009-01-01

    Two radiation mechanisms, inverse Compton scattering (ICS) and synchrotron radiation (SR), suffice within the cannonball (CB) model of long gamma ray bursts (LGRBs) and X-ray flashes (XRFs) to provide a very simple and accurate description of their observed prompt emission and afterglows. Simple as they are, the two mechanisms and the burst environment generate the rich structure of the light curves at all frequencies and times. This is demonstrated for 33 selected Swift LGRBs and XRFs, which are well sampled from early time until late time and well represent the entire diversity of the broad band light curves of Swift LGRBs and XRFs. Their prompt gamma-ray and X-ray emission is dominated by ICS of glory light. During their fast decline phase, ICS is taken over by SR which dominates their broad band afterglow. The pulse shape and spectral evolution of the gamma-ray peaks and the early-time X-ray flares, and even the delayed optical `humps' in XRFs, are correctly predicted. The canonical and non-canonical X-ra...

  5. Recruiting Transcultural Qualitative Research Participants: A Conceptual Model

    Directory of Open Access Journals (Sweden)

    Phyllis Eide

    2005-06-01

    Full Text Available Working with diverse populations poses many challenges to the qualitative researcher who is a member of the dominant culture. Traditional methods of recruitment and selection (such as flyers and advertisements are often unproductive, leading to missed contributions from potential participants who were not recruited and researcher frustration. In this article, the authors explore recruitment issues related to the concept of personal knowing based on experiences with Aboriginal Hawai'ian and Micronesian populations, wherein knowing and being known are crucial to successful recruitment of participants. They present a conceptual model that incorporates key concepts of knowing the other, cultural context, and trust to guide other qualitative transcultural researchers. They also describe challenges, implications, and concrete suggestions for recruitment of participants.

  6. Comparative analysis of 5 lung cancer natural history and screening models that reproduce outcomes of the NLST and PLCO trials.

    Science.gov (United States)

    Meza, Rafael; ten Haaf, Kevin; Kong, Chung Yin; Erdogan, Ayca; Black, William C; Tammemagi, Martin C; Choi, Sung Eun; Jeon, Jihyoun; Han, Summer S; Munshi, Vidit; van Rosmalen, Joost; Pinsky, Paul; McMahon, Pamela M; de Koning, Harry J; Feuer, Eric J; Hazelton, William D; Plevritis, Sylvia K

    2014-06-01

    The National Lung Screening Trial (NLST) demonstrated that low-dose computed tomography screening is an effective way of reducing lung cancer (LC) mortality. However, optimal screening strategies have not been determined to date and it is uncertain whether lighter smokers than those examined in the NLST may also benefit from screening. To address these questions, it is necessary to first develop LC natural history models that can reproduce NLST outcomes and simulate screening programs at the population level. Five independent LC screening models were developed using common inputs and calibration targets derived from the NLST and the Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial (PLCO). Imputation of missing information regarding smoking, histology, and stage of disease for a small percentage of individuals and diagnosed LCs in both trials was performed. Models were calibrated to LC incidence, mortality, or both outcomes simultaneously. Initially, all models were calibrated to the NLST and validated against PLCO. Models were found to validate well against individuals in PLCO who would have been eligible for the NLST. However, all models required further calibration to PLCO to adequately capture LC outcomes in PLCO never-smokers and light smokers. Final versions of all models produced incidence and mortality outcomes in the presence and absence of screening that were consistent with both trials. The authors developed 5 distinct LC screening simulation models based on the evidence in the NLST and PLCO. The results of their analyses demonstrated that the NLST and PLCO have produced consistent results. The resulting models can be important tools to generate additional evidence to determine the effectiveness of lung cancer screening strategies using low-dose computed tomography. © 2014 American Cancer Society.

  7. ARCHITECTURES AND ALGORITHMS FOR COGNITIVE NETWORKS ENABLED BY QUALITATIVE MODELS

    DEFF Research Database (Denmark)

    Balamuralidhar, P.

    2013-01-01

    Complexity of communication networks is ever increasing and getting complicated by their heterogeneity and dynamism. Traditional techniques are facing challenges in network performance management. Cognitive networking is an emerging paradigm to make networks more intelligent, thereby overcoming...... of the cognitive engine that incorporates a context space based information structure to its knowledge model. I propose a set of guiding principles behind a cognitive system to be autonomic and use them with additional requirements to build a detailed architecture for the cognitive engine. I define a context space...... structure integrating various information structures that are required for the knowledge model. Use graphical models towards representing and reasoning about context space is a direction followed here. Specifically I analyze the framework of qualitative models for their suitability to represent the dynamic...

  8. QSAR DataBank repository: open and linked qualitative and quantitative structure-activity relationship models.

    Science.gov (United States)

    Ruusmann, V; Sild, S; Maran, U

    2015-01-01

    Structure-activity relationship models have been used to gain insight into chemical and physical processes in biomedicine, toxicology, biotechnology, etc. for almost a century. They have been recognized as valuable tools in decision support workflows for qualitative and quantitative predictions. The main obstacle preventing broader adoption of quantitative structure-activity relationships [(Q)SARs] is that published models are still relatively difficult to discover, retrieve and redeploy in a modern computer-oriented environment. This publication describes a digital repository that makes in silico (Q)SAR-type descriptive and predictive models archivable, citable and usable in a novel way for most common research and applied science purposes. The QSAR DataBank (QsarDB) repository aims to make the processes and outcomes of in silico modelling work transparent, reproducible and accessible. Briefly, the models are represented in the QsarDB data format and stored in a content-aware repository (a.k.a. smart repository). Content awareness has two dimensions. First, models are organized into collections and then into collection hierarchies based on their metadata. Second, the repository is not only an environment for browsing and downloading models (the QDB archive) but also offers integrated services, such as model analysis and visualization and prediction making. The QsarDB repository unlocks the potential of descriptive and predictive in silico (Q)SAR-type models by allowing new and different types of collaboration between model developers and model users. The key enabling factor is the representation of (Q)SAR models in the QsarDB data format, which makes it easy to preserve and share all relevant data, information and knowledge. Model developers can become more productive by effectively reusing prior art. Model users can make more confident decisions by relying on supporting information that is larger and more diverse than before. Furthermore, the smart repository

  9. Can the CMIP5 models reproduce interannual to interdecadal southern African summer rainfall variability and their teleconnections?

    Science.gov (United States)

    Dieppois, Bastien; Pohl, Benjamin; Crétat, Julien; Keenlyside, Noel; New, Mark

    2017-04-01

    This study examines for the first time the ability of 28 global climate models from the Coupled Model Intercomparison Project 5 (CMIP5) to reproduce southern African summer rainfall variability and their teleconnections with large-scale modes of climate variability across the dominant timescales. In observations, summer southern African rainfall exhibits three significant timescales of variability over the twentieth century: interdecadal (15-28 years), quasi-decadal (8-13 years), and interannual (2-8 years). Most of CMIP5 simulations underestimate southern African summer rainfall variability at these three timescales, and this bias is proportionally stronger from high- to low-frequency. The inter-model spread is as important as the spread between the ensemble members of a given model, which suggests a strong influence of internal climate variability, and/or large model uncertainties. The underestimated amplitude of rainfall variability for each timescale are linked to unrealistic spatial distributions of these fluctuations over the subcontinent in most CMIP5 models. This is, at least partially, due to a poor representation of the tropical/subtropical teleconnections, which are known to favour wet conditions over southern African rainfall in the observations. Most CMIP5 realisations (85%) fail at simulating sea-surface temperature (SST) anomalies related to a negative Pacific Decadal Oscillation during wetter conditions at the interdecadal timescale. At the quasi-decadal timescale, only one-third of simulations display a negative Interdecadal Pacific Oscillation during wetter conditions, but these SST anomalies are anomalously shifted westward and poleward when compared to observed anomalies. Similar biases in simulating La Niña SST anomalies are identified in more than 50% of CMIP5 simulations at the interannual timescale. These biases in Pacific SST anomalies result in important shifts in the Walker circulation. This impacts southern Africa rainfall variability

  10. Can CFMIP2 models reproduce the leading modes of cloud vertical structure in the CALIPSO-GOCCP observations?

    Science.gov (United States)

    Wang, Fang; Yang, Song

    2018-02-01

    Using principal component (PC) analysis, three leading modes of cloud vertical structure (CVS) are revealed by the GCM-Oriented CALIPSO Cloud Product (GOCCP), i.e. tropical high, subtropical anticyclonic and extratropical cyclonic cloud modes (THCM, SACM and ECCM, respectively). THCM mainly reflect the contrast between tropical high clouds and clouds in middle/high latitudes. SACM is closely associated with middle-high clouds in tropical convective cores, few-cloud regimes in subtropical anticyclonic clouds and stratocumulus over subtropical eastern oceans. ECCM mainly corresponds to clouds along extratropical cyclonic regions. Models of phase 2 of Cloud Feedback Model Intercomparison Project (CFMIP2) well reproduce the THCM, but SACM and ECCM are generally poorly simulated compared to GOCCP. Standardized PCs corresponding to CVS modes are generally captured, whereas original PCs (OPCs) are consistently underestimated (overestimated) for THCM (SACM and ECCM) by CFMIP2 models. The effects of CVS modes on relative cloud radiative forcing (RSCRF/RLCRF) (RSCRF being calculated at the surface while RLCRF at the top of atmosphere) are studied in terms of principal component regression method. Results show that CFMIP2 models tend to overestimate (underestimated or simulate the opposite sign) RSCRF/RLCRF radiative effects (REs) of ECCM (THCM and SACM) in unit global mean OPC compared to observations. These RE biases may be attributed to two factors, one of which is underestimation (overestimation) of low/middle clouds (high clouds) (also known as stronger (weaker) REs in unit low/middle (high) clouds) in simulated global mean cloud profiles, the other is eigenvector biases in CVS modes (especially for SACM and ECCM). It is suggested that much more attention should be paid on improvement of CVS, especially cloud parameterization associated with particular physical processes (e.g. downwelling regimes with the Hadley circulation, extratropical storm tracks and others), which

  11. Reproducing Electric Field Observations during Magnetic Storms by means of Rigorous 3-D Modelling and Distortion Matrix Co-estimation

    Science.gov (United States)

    Püthe, Christoph; Manoj, Chandrasekharan; Kuvshinov, Alexey

    2015-04-01

    Electric fields induced in the conducting Earth during magnetic storms drive currents in power transmission grids, telecommunication lines or buried pipelines. These geomagnetically induced currents (GIC) can cause severe service disruptions. The prediction of GIC is thus of great importance for public and industry. A key step in the prediction of the hazard to technological systems during magnetic storms is the calculation of the geoelectric field. To address this issue for mid-latitude regions, we developed a method that involves 3-D modelling of induction processes in a heterogeneous Earth and the construction of a model of the magnetospheric source. The latter is described by low-degree spherical harmonics; its temporal evolution is derived from observatory magnetic data. Time series of the electric field can be computed for every location on Earth's surface. The actual electric field however is known to be perturbed by galvanic effects, arising from very local near-surface heterogeneities or topography, which cannot be included in the conductivity model. Galvanic effects are commonly accounted for with a real-valued time-independent distortion matrix, which linearly relates measured and computed electric fields. Using data of various magnetic storms that occurred between 2000 and 2003, we estimated distortion matrices for observatory sites onshore and on the ocean bottom. Strong correlations between modellings and measurements validate our method. The distortion matrix estimates prove to be reliable, as they are accurately reproduced for different magnetic storms. We further show that 3-D modelling is crucial for a correct separation of galvanic and inductive effects and a precise prediction of electric field time series during magnetic storms. Since the required computational resources are negligible, our approach is suitable for a real-time prediction of GIC. For this purpose, a reliable forecast of the source field, e.g. based on data from satellites

  12. QSAR model reproducibility and applicability: a case study of rate constants of hydroxyl radical reaction models applied to polybrominated diphenyl ethers and (benzo-)triazoles.

    Science.gov (United States)

    Roy, Partha Pratim; Kovarich, Simona; Gramatica, Paola

    2011-08-01

    The crucial importance of the three central OECD principles for quantitative structure-activity relationship (QSAR) model validation is highlighted in a case study of tropospheric degradation of volatile organic compounds (VOCs) by OH, applied to two CADASTER chemical classes (PBDEs and (benzo-)triazoles). The application of any QSAR model to chemicals without experimental data largely depends on model reproducibility by the user. The reproducibility of an unambiguous algorithm (OECD Principle 2) is guaranteed by redeveloping MLR models based on both updated version of DRAGON software for molecular descriptors calculation and some freely available online descriptors. The Genetic Algorithm has confirmed its ability to always select the most informative descriptors independently on the input pool of variables. The ability of the GA-selected descriptors to model chemicals not used in model development is verified by three different splittings (random by response, K-ANN and K-means clustering), thus ensuring the external predictivity of the new models, independently of the training/prediction set composition (OECD Principle 5). The relevance of checking the structural applicability domain becomes very evident on comparing the predictions for CADASTER chemicals, using the new models proposed herein, with those obtained by EPI Suite. Copyright © 2011 Wiley Periodicals, Inc.

  13. Eccentric Contraction-Induced Muscle Injury: Reproducible, Quantitative, Physiological Models to Impair Skeletal Muscle’s Capacity to Generate Force

    Science.gov (United States)

    Call, Jarrod A.; Lowe, Dawn A.

    2018-01-01

    In order to investigate the molecular and cellular mechanisms of muscle regeneration an experimental injury model is required. Advantages of eccentric contraction-induced injury are that it is a controllable, reproducible, and physiologically relevant model to cause muscle injury, with injury being defined as a loss of force generating capacity. While eccentric contractions can be incorporated into conscious animal study designs such as downhill treadmill running, electrophysiological approaches to elicit eccentric contractions and examine muscle contractility, for example before and after the injurious eccentric contractions, allows researchers to circumvent common issues in determining muscle function in a conscious animal (e.g., unwillingness to participate). Herein, we describe in vitro and in vivo methods that are reliable, repeatable, and truly maximal because the muscle contractions are evoked in a controlled, quantifiable manner independent of subject motivation. Both methods can be used to initiate eccentric contraction-induced injury and are suitable for monitoring functional muscle regeneration hours to days to weeks post-injury. PMID:27492161

  14. Eccentric Contraction-Induced Muscle Injury: Reproducible, Quantitative, Physiological Models to Impair Skeletal Muscle's Capacity to Generate Force.

    Science.gov (United States)

    Call, Jarrod A; Lowe, Dawn A

    2016-01-01

    In order to investigate the molecular and cellular mechanisms of muscle regeneration an experimental injury model is required. Advantages of eccentric contraction-induced injury are that it is a controllable, reproducible, and physiologically relevant model to cause muscle injury, with injury being defined as a loss of force generating capacity. While eccentric contractions can be incorporated into conscious animal study designs such as downhill treadmill running, electrophysiological approaches to elicit eccentric contractions and examine muscle contractility, for example before and after the injurious eccentric contractions, allows researchers to circumvent common issues in determining muscle function in a conscious animal (e.g., unwillingness to participate). Herein, we describe in vitro and in vivo methods that are reliable, repeatable, and truly maximal because the muscle contractions are evoked in a controlled, quantifiable manner independent of subject motivation. Both methods can be used to initiate eccentric contraction-induced injury and are suitable for monitoring functional muscle regeneration hours to days to weeks post-injury.

  15. A sensitive and reproducible in vivo imaging mouse model for evaluation of drugs against late-stage human African trypanosomiasis.

    Science.gov (United States)

    Burrell-Saward, Hollie; Rodgers, Jean; Bradley, Barbara; Croft, Simon L; Ward, Theresa H

    2015-02-01

    To optimize the Trypanosoma brucei brucei GVR35 VSL-2 bioluminescent strain as an innovative drug evaluation model for late-stage human African trypanosomiasis. An IVIS® Lumina II imaging system was used to detect bioluminescent T. b. brucei GVR35 parasites in mice to evaluate parasite localization and disease progression. Drug treatment was assessed using qualitative bioluminescence imaging and real-time quantitative PCR (qPCR). We have shown that drug dose-response can be evaluated using bioluminescence imaging and confirmed quantification of tissue parasite load using qPCR. The model was also able to detect drug relapse earlier than the traditional blood film detection and even in the absence of any detectable peripheral parasites. We have developed and optimized a new, efficient method to evaluate novel anti-trypanosomal drugs in vivo and reduce the current 180 day drug relapse experiment to a 90 day model. The non-invasive in vivo imaging model reduces the time required to assess preclinical efficacy of new anti-trypanosomal drugs. © The Author 2014. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  16. A rat model of post-traumatic stress disorder reproduces the hippocampal deficits seen in the human syndrome

    Directory of Open Access Journals (Sweden)

    Sonal eGoswami

    2012-06-01

    Full Text Available Despite recent progress, the causes and pathophysiology of post-traumatic stress disorder (PTSD remain poorly understood, partly because of ethical limitations inherent to human studies. One approach to circumvent this obstacle is to study PTSD in a valid animal model of the human syndrome. In one such model, extreme and long-lasting behavioral manifestations of anxiety develop in a subset of Lewis rats after exposure to an intense predatory threat that mimics the type of life-and-death situation known to precipitate PTSD in humans. This study aimed to assess whether the hippocampus-associated deficits observed in the human syndrome are reproduced in this rodent model. Prior to predatory threat, different groups of rats were each tested on one of three object recognition memory tasks that varied in the types of contextual clues (i.e. that require the hippocampus or not the rats could use to identify novel items. After task completion, the rats were subjected to predatory threat and, one week later, tested on the elevated plus maze. Based on their exploratory behavior in the plus maze, rats were then classified as resilient or PTSD-like and their performance on the pre-threat object recognition tasks compared. The performance of PTSD-like rats was inferior to that of resilient rats but only when subjects relied on an allocentric frame of reference to identify novel items, a process thought to be critically dependent on the hippocampus. Therefore, these results suggest that even prior to trauma, PTSD-like rats show a deficit in hippocampal-dependent functions, as reported in twin studies of human PTSD.

  17. Reproducing the organic matter model of anthropogenic dark earth of Amazonia and testing the ecotoxicity of functionalized charcoal compounds

    Directory of Open Access Journals (Sweden)

    Carolina Rodrigues Linhares

    2012-05-01

    Full Text Available The objective of this work was to obtain organic compounds similar to the ones found in the organic matter of anthropogenic dark earth of Amazonia (ADE using a chemical functionalization procedure on activated charcoal, as well as to determine their ecotoxicity. Based on the study of the organic matter from ADE, an organic model was proposed and an attempt to reproduce it was described. Activated charcoal was oxidized with the use of sodium hypochlorite at different concentrations. Nuclear magnetic resonance was performed to verify if the spectra of the obtained products were similar to the ones of humic acids from ADE. The similarity between spectra indicated that the obtained products were polycondensed aromatic structures with carboxyl groups: a soil amendment that can contribute to soil fertility and to its sustainable use. An ecotoxicological test with Daphnia similis was performed on the more soluble fraction (fulvic acids of the produced soil amendment. Aryl chloride was formed during the synthesis of the organic compounds from activated charcoal functionalization and partially removed through a purification process. However, it is probable that some aryl chloride remained in the final product, since the ecotoxicological test indicated that the chemical functionalized soil amendment is moderately toxic.

  18. Universal Free School Breakfast: A Qualitative Model for Breakfast Behaviors

    Science.gov (United States)

    Harvey-Golding, Louise; Donkin, Lynn Margaret; Blackledge, John; Defeyter, Margaret Anne

    2015-01-01

    In recent years, the provision of school breakfast has increased significantly in the UK. However, research examining the effectiveness of school breakfast is still within relative stages of infancy, and findings to date have been rather mixed. Moreover, previous evaluations of school breakfast schemes have been predominantly quantitative in their methodologies. Currently, there are few qualitative studies examining the subjective perceptions and experiences of stakeholders, and thereby an absence of knowledge regarding the sociocultural impacts of school breakfast. The purpose of this study was to investigate the beliefs, views and attitudes, and breakfast consumption behaviors, among key stakeholders, served by a council-wide universal free school breakfast initiative, within the North West of England, UK. A sample of children, parents, and school staff were recruited from three primary schools, participating in the universal free school breakfast scheme, to partake in semi-structured interviews and small focus groups. A Grounded Theory analysis of the data collected identified a theoretical model of breakfast behaviors, underpinned by the subjective perceptions and experiences of these key stakeholders. The model comprises of three domains relating to breakfast behaviors, and the internal and external factors that are perceived to influence breakfast behaviors, among children, parents, and school staff. Findings were validated using triangulation methods, member checks, and inter-rater reliability measures. In presenting this theoretically grounded model for breakfast behaviors, this paper provides a unique qualitative insight into the breakfast consumption behaviors and barriers to breakfast consumption, within a socioeconomically deprived community, participating in a universal free school breakfast intervention program. PMID:26125017

  19. Validity, reliability, and reproducibility of linear measurements on digital models obtained from intraoral and cone-beam computed tomography scans of alginate impressions

    NARCIS (Netherlands)

    Wiranto, Matthew G.; Engelbrecht, W. Petrie; Nolthenius, Heleen E. Tutein; van der Meer, W. Joerd; Ren, Yijin

    INTRODUCTION: Digital 3-dimensional models are widely used for orthodontic diagnosis. The aim of this study was to assess the validity, reliability, and reproducibility of digital models obtained from the Lava Chairside Oral scanner (3M ESPE, Seefeld, Germany) and cone-beam computed tomography scans

  20. Reproducibility and accuracy of linear measurements on dental models derived from cone-beam computed tomography compared with digital dental casts

    NARCIS (Netherlands)

    Waard, O. de; Rangel, F.A.; Fudalej, P.S.; Bronkhorst, E.M.; Kuijpers-Jagtman, A.M.; Breuning, K.H.

    2014-01-01

    INTRODUCTION: The aim of this study was to determine the reproducibility and accuracy of linear measurements on 2 types of dental models derived from cone-beam computed tomography (CBCT) scans: CBCT images, and Anatomodels (InVivoDental, San Jose, Calif); these were compared with digital models

  1. Coupled RipCAS-DFLOW (CoRD) Software and Data Management System for Reproducible Floodplain Vegetation Succession Modeling

    Science.gov (United States)

    Turner, M. A.; Miller, S.; Gregory, A.; Cadol, D. D.; Stone, M. C.; Sheneman, L.

    2016-12-01

    We present the Coupled RipCAS-DFLOW (CoRD) modeling system created to encapsulate the workflow to analyze the effects of stream flooding on vegetation succession. CoRD provides an intuitive command-line and web interface to run DFLOW and RipCAS in succession over many years automatically, which is a challenge because, for our application, DFLOW must be run on a supercomputing cluster via the PBS job scheduler. RipCAS is a vegetation succession model, and DFLOW is a 2D open channel flow model. Data adaptors have been developed to seamlessly connect DFLOW output data to be RipCAS inputs, and vice-versa. CoRD provides automated statistical analysis and visualization, plus automatic syncing of input and output files and model run metadata to the hydrological data management system HydroShare using its excellent Python REST client. This combination of technologies and data management techniques allows the results to be shared with collaborators and eventually published. Perhaps most importantly, it allows results to be easily reproduced via either the command-line or web user interface. This system is a result of collaboration between software developers and hydrologists participating in the Western Consortium for Watershed Analysis, Visualization, and Exploration (WC-WAVE). Because of the computing-intensive nature of this particular workflow, including automating job submission/monitoring and data adaptors, software engineering expertise is required. However, the hydrologists provide the software developers with a purpose and ensure a useful, intuitive tool is developed. Our hydrologists contribute software, too: RipCAS was developed from scratch by hydrologists on the team as a specialized, open-source version of the Computer Aided Simulation Model for Instream Flow and Riparia (CASiMiR) vegetation model; our hydrologists running DFLOW provided numerous examples and help with the supercomputing system. This project is written in Python, a popular language in the

  2. Relapse Model among Iranian Drug Users: A Qualitative Study.

    Science.gov (United States)

    Jalali, Amir; Seyedfatemi, Naiemeh; Peyrovi, Hamid

    2015-01-01

    Relapse is a common problem in drug user's rehabilitation program and reported in all over the country. An in-depth study on patients' experiences can be used for exploring the relapse process among drug users. Therefore, this study suggests a model for relapse process among Iranian drug users. In this qualitative study with grounded theory approach, 22 participants with rich information about the phenomenon under the study were selected using purposive, snowball and theoretical sampling methods. After obtaining the informed consent, data were collected based on face-to-face, in-depth, semi-structured interviews. All interviews were analyzed in three stages of axial, selective and open coding methods. Nine main categories emerged, including avoiding of drugs, concerns about being accepted, family atmosphere, social conditions, mental challenge, self-management, self-deception, use and remorse and a main category, feeling of loss as the core variable. Mental challenge has two subcategories, evoking pleasure and craving. Relapse model is a dynamic and systematic process including from cycles of drug avoidance to remorse with a core variable as feeling of loss.  Relapse process is a dynamic and systematic process that needs an effective control. Determining a relapse model as a clear process could be helpful in clinical sessions. RESULTS of this research have depicted relapse process among Iranian drugs user by conceptual model.

  3. Learning about Ecological Systems by Constructing Qualitative Models with DynaLearn

    Science.gov (United States)

    Leiba, Moshe; Zuzovsky, Ruth; Mioduser, David; Benayahu, Yehuda; Nachmias, Rafi

    2012-01-01

    A qualitative model of a system is an abstraction that captures ordinal knowledge and predicts the set of qualitatively possible behaviours of the system, given a qualitative description of its structure and initial state. This paper examines an innovative approach to science education using an interactive learning environment that supports…

  4. Qualitative modeling of the decision-making process using electrooculography.

    Science.gov (United States)

    Zargari Marandi, Ramtin; Sabzpoushan, S H

    2015-12-01

    A novel method based on electrooculography (EOG) has been introduced in this work to study the decision-making process. An experiment was designed and implemented wherein subjects were asked to choose between two items from the same category that were presented within a limited time. The EOG and voice signals of the subjects were recorded during the experiment. A calibration task was performed to map the EOG signals to their corresponding gaze positions on the screen by using an artificial neural network. To analyze the data, 16 parameters were extracted from the response time and EOG signals of the subjects. Evaluation and comparison of the parameters, together with subjects' choices, revealed functional information. On the basis of this information, subjects switched their eye gazes between items about three times on average. We also found, according to statistical hypothesis testing-that is, a t test, t(10) = 71.62, SE = 1.25, p < .0001-that the correspondence rate of a subjects' gaze at the moment of selection with the selected item was significant. Ultimately, on the basis of these results, we propose a qualitative choice model for the decision-making task.

  5. The Need for Reproducibility

    Energy Technology Data Exchange (ETDEWEB)

    Robey, Robert W. [Los Alamos National Laboratory

    2016-06-27

    The purpose of this presentation is to consider issues of reproducibility, specifically it determines whether bitwise reproducible computation is possible, if computational research in DOE improves its publication process, and if reproducible results can be achieved apart from the peer review process?

  6. Reliability versus reproducibility

    International Nuclear Information System (INIS)

    Lautzenheiser, C.E.

    1976-01-01

    Defect detection and reproducibility of results are two separate but closely related subjects. It is axiomatic that a defect must be detected from examination to examination or reproducibility of results is very poor. On the other hand, a defect can be detected on each of subsequent examinations for higher reliability and still have poor reproducibility of results

  7. Environmental Consequences of Wildlife Tourism: The Use of Formalised Qualitative Models

    Directory of Open Access Journals (Sweden)

    Veselý Štěpán

    2015-09-01

    Full Text Available The paper presents a simple qualitative model of environmental consequences of wildlife tourism. Qualitative models use just three values: Positive/Increasing, Zero/Constant and Negative/Decreasing. Such quantifiers of trends are the least information intensive. Qualitative models can be useful, since models of wildlife tourism include such variables as, for example, Biodiversity (BIO, Animals’ habituation to tourists (HAB or Plant composition change (PLA that are sometimes difficult or costly to quantify. Hence, a significant fraction of available information about wildlife tourism and its consequences is not of numerical nature, for example, if HAB is increasing then BIO is decreasing. Such equationless relations are studied in this paper. The model has 10 variables and 20 equationless pairwise interrelations among them. The model is solved and 15 solutions, that is, scenarios are obtained. All qualitative states, including the first and second qualitative derivatives with respect to time, of all variables are specified for each scenario.

  8. Phoenix – A model-based Human Reliability Analysis methodology: Qualitative Analysis Procedure

    International Nuclear Information System (INIS)

    Ekanem, Nsimah J.; Mosleh, Ali; Shen, Song-Hua

    2016-01-01

    Phoenix method is an attempt to address various issues in the field of Human Reliability Analysis (HRA). Built on a cognitive human response model, Phoenix incorporates strong elements of current HRA good practices, leverages lessons learned from empirical studies, and takes advantage of the best features of existing and emerging HRA methods. Its original framework was introduced in previous publications. This paper reports on the completed methodology, summarizing the steps and techniques of its qualitative analysis phase. The methodology introduces the “Crew Response Tree” which provides a structure for capturing the context associated with Human Failure Events (HFEs), including errors of omission and commission. It also uses a team-centered version of the Information, Decision and Action cognitive model and “macro-cognitive” abstractions of crew behavior, as well as relevant findings from cognitive psychology literature and operating experience, to identify potential causes of failures and influencing factors during procedure-driven and knowledge-supported crew-plant interactions. The result is the set of identified HFEs and likely scenarios leading to each. The methodology itself is generic in the sense that it is compatible with various quantification methods, and can be adapted for use across different environments including nuclear, oil and gas, aerospace, aviation, and healthcare. - Highlights: • Produces a detailed, consistent, traceable, reproducible and properly documented HRA. • Uses “Crew Response Tree” to capture context associated with Human Failure Events. • Models dependencies between Human Failure Events and influencing factors. • Provides a human performance model for relating context to performance. • Provides a framework for relating Crew Failure Modes to its influencing factors.

  9. From Peer-Reviewed to Peer-Reproduced in Scholarly Publishing: The Complementary Roles of Data Models and Workflows in Bioinformatics.

    Directory of Open Access Journals (Sweden)

    Alejandra González-Beltrán

    Full Text Available Reproducing the results from a scientific paper can be challenging due to the absence of data and the computational tools required for their analysis. In addition, details relating to the procedures used to obtain the published results can be difficult to discern due to the use of natural language when reporting how experiments have been performed. The Investigation/Study/Assay (ISA, Nanopublications (NP, and Research Objects (RO models are conceptual data modelling frameworks that can structure such information from scientific papers. Computational workflow platforms can also be used to reproduce analyses of data in a principled manner. We assessed the extent by which ISA, NP, and RO models, together with the Galaxy workflow system, can capture the experimental processes and reproduce the findings of a previously published paper reporting on the development of SOAPdenovo2, a de novo genome assembler.Executable workflows were developed using Galaxy, which reproduced results that were consistent with the published findings. A structured representation of the information in the SOAPdenovo2 paper was produced by combining the use of ISA, NP, and RO models. By structuring the information in the published paper using these data and scientific workflow modelling frameworks, it was possible to explicitly declare elements of experimental design, variables, and findings. The models served as guides in the curation of scientific information and this led to the identification of inconsistencies in the original published paper, thereby allowing its authors to publish corrections in the form of an errata.SOAPdenovo2 scripts, data, and results are available through the GigaScience Database: http://dx.doi.org/10.5524/100044; the workflows are available from GigaGalaxy: http://galaxy.cbiit.cuhk.edu.hk; and the representations using the ISA, NP, and RO models are available through the SOAPdenovo2 case study website http://isa-tools.github.io/soapdenovo2

  10. Testing Reproducibility in Earth Sciences

    Science.gov (United States)

    Church, M. A.; Dudill, A. R.; Frey, P.; Venditti, J. G.

    2017-12-01

    Reproducibility represents how closely the results of independent tests agree when undertaken using the same materials but different conditions of measurement, such as operator, equipment or laboratory. The concept of reproducibility is fundamental to the scientific method as it prevents the persistence of incorrect or biased results. Yet currently the production of scientific knowledge emphasizes rapid publication of previously unreported findings, a culture that has emerged from pressures related to hiring, publication criteria and funding requirements. Awareness and critique of the disconnect between how scientific research should be undertaken, and how it actually is conducted, has been prominent in biomedicine for over a decade, with the fields of economics and psychology more recently joining the conversation. The purpose of this presentation is to stimulate the conversation in earth sciences where, despite implicit evidence in widely accepted classifications, formal testing of reproducibility is rare.As a formal test of reproducibility, two sets of experiments were undertaken with the same experimental procedure, at the same scale, but in different laboratories. Using narrow, steep flumes and spherical glass beads, grain size sorting was examined by introducing fine sediment of varying size and quantity into a mobile coarse bed. The general setup was identical, including flume width and slope; however, there were some variations in the materials, construction and lab environment. Comparison of the results includes examination of the infiltration profiles, sediment mobility and transport characteristics. The physical phenomena were qualitatively reproduced but not quantitatively replicated. Reproduction of results encourages more robust research and reporting, and facilitates exploration of possible variations in data in various specific contexts. Following the lead of other fields, testing of reproducibility can be incentivized through changes to journal

  11. Use of model-based qualitative icons and adaptive windows in workstations for supervisory control systems

    Science.gov (United States)

    Mitchell, Christine M.; Saisi, Donna L.

    1987-01-01

    The effectiveness of an operator interface using qualitative icons and dynamic windows designed and controlled by means of an operator function model is demonstrated, and the simulation system, the Georgia Tech-Multisatellite Operations Control Center, is described. Qualitative icons are used to integrate low-level quantitative data into high-level qualitative error detection mechanisms, and window technology is used for the simultaneous display of multiple data sources that reflect different aspects of the system state. Based on eleven experimental measures, the workstation incorporating the model-based qualitative icons and dynamic operator function window sets was found to perform better than the conventional workstation.

  12. A qualitative model construction method of nuclear power plants for effective diagnostic knowledge generation

    International Nuclear Information System (INIS)

    Yoshikawa, Shinji; Endou, Akira; Kitamura, Yoshinobu; Sasajima, Munehiko; Ikeda, Mitsuru; Mizoguchi, Riichiro.

    1994-01-01

    This paper discusses a method to construct a qualitative model of a nuclear power plant, in order to generate effective diagnostic knowledge. The proposed method is to prepare deep knowledge to be provided to a knowledge compiler based upon qualitative reasoning (QR). Necessity of knowledge compilation for nuclear plant diagnosis will be explained first, and conventionally-experienced problems in qualitative reasoning and a proposed method to overcome this problem is shown next, then a sample procedure to build a qualitative nuclear plant model is demonstrated. (author)

  13. Statistical Methods for the Qualitative Assessment of Dynamic Models with Time Delay (R Package qualV

    Directory of Open Access Journals (Sweden)

    Stefanie Jachner

    2007-06-01

    Full Text Available Results of ecological models differ, to some extent, more from measured data than from empirical knowledge. Existing techniques for validation based on quantitative assessments sometimes cause an underestimation of the performance of models due to time shifts, accelerations and delays or systematic differences between measurement and simulation. However, for the application of such models it is often more important to reproduce essential patterns instead of seemingly exact numerical values. This paper presents techniques to identify patterns and numerical methods to measure the consistency of patterns between observations and model results. An orthogonal set of deviance measures for absolute, relative and ordinal scale was compiled to provide informations about the type of difference. Furthermore, two different approaches accounting for time shifts were presented. The first one transforms the time to take time delays and speed differences into account. The second one describes known qualitative criteria dividing time series into interval units in accordance to their main features. The methods differ in their basic concepts and in the form of the resulting criteria. Both approaches and the deviance measures discussed are implemented in an R package. All methods are demonstrated by means of water quality measurements and simulation data. The proposed quality criteria allow to recognize systematic differences and time shifts between time series and to conclude about the quantitative and qualitative similarity of patterns.

  14. 3D-modeling of the spine using EOS imaging system: Inter-reader reproducibility and reliability.

    Science.gov (United States)

    Rehm, Johannes; Germann, Thomas; Akbar, Michael; Pepke, Wojciech; Kauczor, Hans-Ulrich; Weber, Marc-André; Spira, Daniel

    2017-01-01

    To retrospectively assess the interreader reproducibility and reliability of EOS 3D full spine reconstructions in patients with adolescent idiopathic scoliosis (AIS). 73 patients with mean age of 17 years and a moderate AIS (median Cobb Angle 18.2°) obtained low-dose standing biplanar radiographs with EOS. Two independent readers performed "full spine" 3D reconstructions of the spine with the "full-spine" method adjusting the bone contour of every thoracic and lumbar vertebra (Th1-L5). Interreader reproducibility was assessed regarding rotation of every single vertebra in the coronal (i.e. frontal), sagittal (i.e. lateral), and axial plane, T1/T12 kyphosis, T4/T12 kyphosis, L1/L5 lordosis, L1/S1 lordosis and pelvic parameters. Radiation exposure, scan-time and 3D reconstruction time were recorded. Interclass correlation (ICC) ranged between 0.83 and 0.98 for frontal vertebral rotation, between 0.94 and 0.99 for lateral vertebral rotation and between 0.51 and 0.88 for axial vertebral rotation. ICC was 0.92 for T1/T12 kyphosis, 0.95 for T4/T12 kyphosis, 0.90 for L1/L5 lordosis, 0.85 for L1/S1 lordosis, 0.97 for pelvic incidence, 0.96 for sacral slope, 0.98 for sagittal pelvic tilt and 0.94 for lateral pelvic tilt. The mean time for reconstruction was 14.9 minutes (reader 1: 14.6 minutes, reader 2: 15.2 minutes, p3D angle measurement of vertebral rotation proved to be reliable and was performed in an acceptable reconstruction time. Interreader reproducibility of axial rotation was limited to some degree in the upper and middle thoracic spine due the obtuse angulation of the pedicles and the processi spinosi in the frontal view somewhat complicating their delineation.

  15. Dynamic contrast-enhanced computed tomography in metastatic nasopharyngeal carcinoma: reproducibility analysis and observer variability of the distributed parameter model.

    Science.gov (United States)

    Ng, Quan-Sing; Thng, Choon Hua; Lim, Wan Teck; Hartono, Septian; Thian, Yee Liang; Lee, Puor Sherng; Tan, Daniel Shao-Weng; Tan, Eng Huat; Koh, Tong San

    2012-01-01

    To determine the reproducibility and observer variability of distributed parameter analysis of dynamic contrast-enhanced computed tomography (DCE-CT) data in metastatic nasopharyngeal carcinoma, and to compare 2 approaches of region-of-interest (ROI) analyses. Following ethical approval and informed consent, 17 patients with nasopharyngeal carcinoma underwent paired DCE-CT examinations on a 64-detector scanner, measuring tumor blood flow (F, mL/100 mL/min), permeability surface area product (PS, mL/100 mL/min), fractional intravascular blood volume (v1, mL/100 mL), and fractional extracellular-extravascular volume (v2, mL/100 mL). Tumor parameters were derived by fitting (i) the ROI-averaged concentration-time curve, and (ii) the median value of parameters from voxel-level concentration-time curves. Measurement reproducibility and inter- and intraobserver variability were estimated using Bland-Altman statistics. Mean F, PS, v1, and v2 are 44.9, 20.4, 7.1, and 34.1 for ROI analysis, and 49.0, 18.7, 6.7, and 34.0 for voxel analysis, respectively. Within-subject coefficients of variation are 38.8%, 49.5%, 54.2%, and 35.9% for ROI analysis, and 15.0%, 35.1%, 33.0%, and 21.0% for voxel analysis, respectively. Repeatability coefficients are 48.2, 28.0, 10.7, and 33.9 for ROI analysis, and 20.3, 18.2, 6.1 and 19.8 for voxel analysis, respectively. Intra- and interobserver correlation coefficient ranged from 0.94 to 0.97 and 0.90 to 0.95 for voxel analysis, and 0.73 to 0.87 and 0.72 to 0.94 for ROI analysis, respectively. Measurements of F and v2 appear more reproducible than PS and v1. Voxel-level analysis improves both reproducibility and observer variability compared with ROI-averaged analysis and may retain information about tumor spatial heterogeneity.

  16. Disaster Reintegration Model: A Qualitative Analysis on Developing Korean Disaster Mental Health Support Model

    Directory of Open Access Journals (Sweden)

    Yun-Jung Choi

    2018-02-01

    Full Text Available This study sought to describe the mental health problems experienced by Korean disaster survivors, using a qualitative research method to provide empirical resources for effective disaster mental health support in Korea. Participants were 16 adults or elderly adults who experienced one or more disasters at least 12 months ago recruited via theoretical sampling. Participants underwent in-depth individual interviews on their disaster experiences, which were recorded and transcribed for qualitative analysis, which followed Strauss and Corbin’s (1998 Grounded theory. After open coding, participants’ experiences were categorized into 130 codes, 43 sub-categories and 17 categories. The categories were further analyzed in a paradigm model, conditional model and the Disaster Reintegration Model, which proposed potentially effective mental health recovery strategies for disaster survivors, health providers and administrators. To provide effective assistance for mental health recovery of disaster survivors, both personal and public resilience should be promoted while considering both cultural and spiritual elements.

  17. Measurement of cerebral blood flow by intravenous xenon-133 technique and a mobile system. Reproducibility using the Obrist model compared to total curve analysis

    DEFF Research Database (Denmark)

    Schroeder, T; Holstein, P; Lassen, N A

    1986-01-01

    was considerably more reproducible than CBF level. Using a single detector instead of five regional values averaged as the hemispheric flow increased standard deviation of CBF level by 10-20%, while the variation in asymmetry was doubled. In optimal measuring conditions the two models revealed no significant...... differences, but in low flow situations the artifact model yielded significantly more stable results. The present apparatus, equipped with 3-5 detectors covering each hemisphere, offers the opportunity of performing serial CBF measurements in situations not otherwise feasible.......The recent development of a mobile 10 detector unit, using i.v. Xenon-133 technique, has made it possible to perform repeated bedside measurements of cerebral blood flow (CBF). Test-retest studies were carried out in 38 atherosclerotic subjects, in order to evaluate the reproducibility of CBF level...

  18. Reproducibility study of [{sup 18}F]FPP(RGD){sub 2} uptake in murine models of human tumor xenografts

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Edwin; Liu, Shuangdong; Chin, Frederick; Cheng, Zhen [Stanford University, Molecular Imaging Program at Stanford, Department of Radiology, School of Medicine, Stanford, CA (United States); Gowrishankar, Gayatri; Yaghoubi, Shahriar [Stanford University, Molecular Imaging Program at Stanford, Department of Radiology, School of Medicine, Stanford, CA (United States); Stanford University, Molecular Imaging Program at Stanford, Department of Bioengineering, School of Medicine, Stanford, CA (United States); Wedgeworth, James Patrick [Stanford University, Molecular Imaging Program at Stanford, Department of Bioengineering, School of Medicine, Stanford, CA (United States); Berndorff, Dietmar; Gekeler, Volker [Bayer Schering Pharma AG, Global Drug Discovery, Berlin (Germany); Gambhir, Sanjiv S. [Stanford University, Molecular Imaging Program at Stanford, Department of Radiology, School of Medicine, Stanford, CA (United States); Stanford University, Molecular Imaging Program at Stanford, Department of Bioengineering, School of Medicine, Stanford, CA (United States); Canary Center at Stanford for Cancer Early Detection, Nuclear Medicine, Departments of Radiology and Bioengineering, Molecular Imaging Program at Stanford, Stanford, CA (United States)

    2011-04-15

    An {sup 18}F-labeled PEGylated arginine-glycine-aspartic acid (RGD) dimer [{sup 18}F]FPP(RGD){sub 2} has been used to image tumor {alpha}{sub v}{beta}{sub 3} integrin levels in preclinical and clinical studies. Serial positron emission tomography (PET) studies may be useful for monitoring antiangiogenic therapy response or for drug screening; however, the reproducibility of serial scans has not been determined for this PET probe. The purpose of this study was to determine the reproducibility of the integrin {alpha}{sub v}{beta}{sub 3}-targeted PET probe, [{sup 18}F ]FPP(RGD){sub 2} using small animal PET. Human HCT116 colon cancer xenografts were implanted into nude mice (n = 12) in the breast and scapular region and grown to mean diameters of 5-15 mm for approximately 2.5 weeks. A 3-min acquisition was performed on a small animal PET scanner approximately 1 h after administration of [{sup 18}F]FPP(RGD){sub 2} (1.9-3.8 MBq, 50-100 {mu}Ci) via the tail vein. A second small animal PET scan was performed approximately 6 h later after reinjection of the probe to assess for reproducibility. Images were analyzed by drawing an ellipsoidal region of interest (ROI) around the tumor xenograft activity. Percentage injected dose per gram (%ID/g) values were calculated from the mean or maximum activity in the ROIs. Coefficients of variation and differences in %ID/g values between studies from the same day were calculated to determine the reproducibility. The coefficient of variation (mean {+-}SD) for %ID{sub mean}/g and %ID{sub max}/g values between [{sup 18}F]FPP(RGD){sub 2} small animal PET scans performed 6 h apart on the same day were 11.1 {+-} 7.6% and 10.4 {+-} 9.3%, respectively. The corresponding differences in %ID{sub mean}/g and %ID{sub max}/g values between scans were -0.025 {+-} 0.067 and -0.039 {+-} 0.426. Immunofluorescence studies revealed a direct relationship between extent of {alpha}{sub {nu}}{beta}{sub 3} integrin expression in tumors and tumor vasculature

  19. [Reproducing and evaluating a rabbit model of multiple organ dysfunction syndrome after cardiopulmonary resuscitation resulted from asphyxia].

    Science.gov (United States)

    Zhang, Dong; Li, Nan; Chen, Ying; Wang, Yu-shan

    2013-02-01

    To evaluate the reproduction of a model of post resuscitation multiple organ dysfunction syndrome (PR-MODS) after cardiac arrest (CA) in rabbit, in order to provide new methods for post-CA treatment. Thirty-five rabbits were randomly divided into three groups, the sham group (n=5), the 7-minute asphyxia group (n=15), and the 8-minute asphyxia group (n=15). The asphyxia CA model was reproduced with tracheal occlusion. After cardiopulmonary resuscitation (CPR), the ratio of recovery of spontaneous circulation (ROSC), the mortality at different time points and the incidence of systemic inflammatory response syndrome (SIRS) were observed in two asphyxia groups. Creatine kinase isoenzyme (CK-MB), alanine aminotransferase (ALT), creatinine (Cr), glucose (Glu) and arterial partial pressure of oxygen (PaO2) levels in blood were measured in the two asphyxia groups before CPR and 12, 24 and 48 hours after ROSC. The survived rabbits were euthanized at 48 hours after ROSC, and heart, brain, lung, kidney, liver, and intestine were harvested for pathological examination using light microscope. PR-MODS after CA was defined based on the function of main organs and their pathological changes. (1) The incidence of ROSC was 100.0% in 7-minute asphyxia group and 86.7% in 8-minute asphyxia group respectively (P>0.05). The 6-hour mortality in 8-minute asphyxia group was significantly higher than that in 7-minute asphyxia group (46.7% vs. 6.7%, P0.05). (2) There was a variety of organ dysfunctions in survived rabbits after ROSC, including chemosis, respiratory distress, hypotension, abdominal distension, weakened or disappearance of bowel peristalsis and oliguria. (3) There was no SIRS or associated changes in major organ function in the sham group. SIRS was observed at 12 - 24 hours after ROSC in the two asphyxia groups. CK-MB was increased significantly at 12 hours after ROSC compared with that before asphyxia (7-minute asphyxia group: 786.88±211.84 U/L vs. 468.20±149.45 U/L, 8

  20. Qualitative Behaviour of a Mathematical Model of Interacting ...

    African Journals Online (AJOL)

    The phenomenon of the interaction between two (2) populations indexed by the unit of time is as old as the famous Lotka-Volterra formalism. However, the qualitative analysis of interacting populations under the simplifying assumption of environmental perturbation is formidable mathematical problem which requires the ...

  1. Development and reproducibility evaluation of a Monte Carlo-based standard LINAC model for quality assurance of multi-institutional clinical trials.

    Science.gov (United States)

    Usmani, Muhammad Nauman; Takegawa, Hideki; Takashina, Masaaki; Numasaki, Hodaka; Suga, Masaki; Anetai, Yusuke; Kurosu, Keita; Koizumi, Masahiko; Teshima, Teruki

    2014-11-01

    Technical developments in radiotherapy (RT) have created a need for systematic quality assurance (QA) to ensure that clinical institutions deliver prescribed radiation doses consistent with the requirements of clinical protocols. For QA, an ideal dose verification system should be independent of the treatment-planning system (TPS). This paper describes the development and reproducibility evaluation of a Monte Carlo (MC)-based standard LINAC model as a preliminary requirement for independent verification of dose distributions. The BEAMnrc MC code is used for characterization of the 6-, 10- and 15-MV photon beams for a wide range of field sizes. The modeling of the LINAC head components is based on the specifications provided by the manufacturer. MC dose distributions are tuned to match Varian Golden Beam Data (GBD). For reproducibility evaluation, calculated beam data is compared with beam data measured at individual institutions. For all energies and field sizes, the MC and GBD agreed to within 1.0% for percentage depth doses (PDDs), 1.5% for beam profiles and 1.2% for total scatter factors (Scps.). Reproducibility evaluation showed that the maximum average local differences were 1.3% and 2.5% for PDDs and beam profiles, respectively. MC and institutions' mean Scps agreed to within 2.0%. An MC-based standard LINAC model developed to independently verify dose distributions for QA of multi-institutional clinical trials and routine clinical practice has proven to be highly accurate and reproducible and can thus help ensure that prescribed doses delivered are consistent with the requirements of clinical protocols. © The Author 2014. Published by Oxford University Press on behalf of The Japan Radiation Research Society and Japanese Society for Radiation Oncology.

  2. Universal free school breakfast: a qualitative model for breakfast behaviors

    OpenAIRE

    Louise eHarvey-Golding; Lynn eDonkin; John eBlackledge; Margaret (Greta) Anne Defeyter

    2015-01-01

    In recent years, the provision of school breakfast has increased significantly in the UK. However, research examining the effectiveness of school breakfast is still within relative stages of infancy, and findings to date have been rather mixed. Moreover, previous evaluations of school breakfast schemes have been predominantly quantitative in their methodologies. Currently, there are few qualitative studies examining the subjective perceptions and experiences of stakeholders, and thereby an ab...

  3. Pangea breakup and northward drift of the Indian subcontinent reproduced by a numerical model of mantle convection.

    Science.gov (United States)

    Yoshida, Masaki; Hamano, Yozo

    2015-02-12

    Since around 200 Ma, the most notable event in the process of the breakup of Pangea has been the high speed (up to 20 cm yr(-1)) of the northward drift of the Indian subcontinent. Our numerical simulations of 3-D spherical mantle convection approximately reproduced the process of continental drift from the breakup of Pangea at 200 Ma to the present-day continental distribution. These simulations revealed that a major factor in the northward drift of the Indian subcontinent was the large-scale cold mantle downwelling that developed spontaneously in the North Tethys Ocean, attributed to the overall shape of Pangea. The strong lateral mantle flow caused by the high-temperature anomaly beneath Pangea, due to the thermal insulation effect, enhanced the acceleration of the Indian subcontinent during the early stage of the Pangea breakup. The large-scale hot upwelling plumes from the lower mantle, initially located under Africa, might have contributed to the formation of the large-scale cold mantle downwelling in the North Tethys Ocean.

  4. Three-dimensional surgical modelling with an open-source software protocol: study of precision and reproducibility in mandibular reconstruction with the fibula free flap.

    Science.gov (United States)

    Ganry, L; Quilichini, J; Bandini, C M; Leyder, P; Hersant, B; Meningaud, J P

    2017-08-01

    Very few surgical teams currently use totally independent and free solutions to perform three-dimensional (3D) surgical modelling for osseous free flaps in reconstructive surgery. This study assessed the precision and technical reproducibility of a 3D surgical modelling protocol using free open-source software in mandibular reconstruction with fibula free flaps and surgical guides. Precision was assessed through comparisons of the 3D surgical guide to the sterilized 3D-printed guide, determining accuracy to the millimetre level. Reproducibility was assessed in three surgical cases by volumetric comparison to the millimetre level. For the 3D surgical modelling, a difference of less than 0.1mm was observed. Almost no deformations (free flap modelling was between 0.1mm and 0.4mm, and the average precision of the complete reconstructed mandible was less than 1mm. The open-source software protocol demonstrated high accuracy without complications. However, the precision of the surgical case depends on the surgeon's 3D surgical modelling. Therefore, surgeons need training on the use of this protocol before applying it to surgical cases; this constitutes a limitation. Further studies should address the transfer of expertise. Copyright © 2017 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

  5. The Proximal Medial Sural Nerve Biopsy Model: A Standardised and Reproducible Baseline Clinical Model for the Translational Evaluation of Bioengineered Nerve Guides

    Directory of Open Access Journals (Sweden)

    Ahmet Bozkurt

    2014-01-01

    Full Text Available Autologous nerve transplantation (ANT is the clinical gold standard for the reconstruction of peripheral nerve defects. A large number of bioengineered nerve guides have been tested under laboratory conditions as an alternative to the ANT. The step from experimental studies to the implementation of the device in the clinical setting is often substantial and the outcome is unpredictable. This is mainly linked to the heterogeneity of clinical peripheral nerve injuries, which is very different from standardized animal studies. In search of a reproducible human model for the implantation of bioengineered nerve guides, we propose the reconstruction of sural nerve defects after routine nerve biopsy as a first or baseline study. Our concept uses the medial sural nerve of patients undergoing diagnostic nerve biopsy (≥2 cm. The biopsy-induced nerve gap was immediately reconstructed by implantation of the novel microstructured nerve guide, Neuromaix, as part of an ongoing first-in-human study. Here we present (i a detailed list of inclusion and exclusion criteria, (ii a detailed description of the surgical procedure, and (iii a follow-up concept with multimodal sensory evaluation techniques. The proximal medial sural nerve biopsy model can serve as a preliminarynature of the injuries or baseline nerve lesion model. In a subsequent step, newly developed nerve guides could be tested in more unpredictable and challenging clinical peripheral nerve lesions (e.g., following trauma which have reduced comparability due to the different nature of the injuries (e.g., site of injury and length of nerve gap.

  6. Reproducibility in Seismic Imaging

    Directory of Open Access Journals (Sweden)

    González-Verdejo O.

    2012-04-01

    Full Text Available Within the field of exploration seismology, there is interest at national level of integrating reproducibility in applied, educational and research activities related to seismic processing and imaging. This reproducibility implies the description and organization of the elements involved in numerical experiments. Thus, a researcher, teacher or student can study, verify, repeat, and modify them independently. In this work, we document and adapt reproducibility in seismic processing and imaging to spread this concept and its benefits, and to encourage the use of open source software in this area within our academic and professional environment. We present an enhanced seismic imaging example, of interest in both academic and professional environments, using Mexican seismic data. As a result of this research, we prove that it is possible to assimilate, adapt and transfer technology at low cost, using open source software and following a reproducible research scheme.

  7. An Integrated Qualitative and Quantitative Biochemical Model Learning Framework Using Evolutionary Strategy and Simulated Annealing.

    Science.gov (United States)

    Wu, Zujian; Pang, Wei; Coghill, George M

    2015-01-01

    Both qualitative and quantitative model learning frameworks for biochemical systems have been studied in computational systems biology. In this research, after introducing two forms of pre-defined component patterns to represent biochemical models, we propose an integrative qualitative and quantitative modelling framework for inferring biochemical systems. In the proposed framework, interactions between reactants in the candidate models for a target biochemical system are evolved and eventually identified by the application of a qualitative model learning approach with an evolution strategy. Kinetic rates of the models generated from qualitative model learning are then further optimised by employing a quantitative approach with simulated annealing. Experimental results indicate that our proposed integrative framework is feasible to learn the relationships between biochemical reactants qualitatively and to make the model replicate the behaviours of the target system by optimising the kinetic rates quantitatively. Moreover, potential reactants of a target biochemical system can be discovered by hypothesising complex reactants in the synthetic models. Based on the biochemical models learned from the proposed framework, biologists can further perform experimental study in wet laboratory. In this way, natural biochemical systems can be better understood.

  8. CONFIG - Adapting qualitative modeling and discrete event simulation for design of fault management systems

    Science.gov (United States)

    Malin, Jane T.; Basham, Bryan D.

    1989-01-01

    CONFIG is a modeling and simulation tool prototype for analyzing the normal and faulty qualitative behaviors of engineered systems. Qualitative modeling and discrete-event simulation have been adapted and integrated, to support early development, during system design, of software and procedures for management of failures, especially in diagnostic expert systems. Qualitative component models are defined in terms of normal and faulty modes and processes, which are defined by invocation statements and effect statements with time delays. System models are constructed graphically by using instances of components and relations from object-oriented hierarchical model libraries. Extension and reuse of CONFIG models and analysis capabilities in hybrid rule- and model-based expert fault-management support systems are discussed.

  9. Oxygen distribution in tumors: A qualitative analysis and modeling study providing a novel Monte Carlo approach

    International Nuclear Information System (INIS)

    Lagerlöf, Jakob H.; Kindblom, Jon; Bernhardt, Peter

    2014-01-01

    Purpose: To construct a Monte Carlo (MC)-based simulation model for analyzing the dependence of tumor oxygen distribution on different variables related to tumor vasculature [blood velocity, vessel-to-vessel proximity (vessel proximity), and inflowing oxygen partial pressure (pO 2 )]. Methods: A voxel-based tissue model containing parallel capillaries with square cross-sections (sides of 10 μm) was constructed. Green's function was used for diffusion calculations and Michaelis-Menten's kinetics to manage oxygen consumption. The model was tuned to approximately reproduce the oxygenational status of a renal carcinoma; the depth oxygenation curves (DOC) were fitted with an analytical expression to facilitate rapid MC simulations of tumor oxygen distribution. DOCs were simulated with three variables at three settings each (blood velocity, vessel proximity, and inflowing pO 2 ), which resulted in 27 combinations of conditions. To create a model that simulated variable oxygen distributions, the oxygen tension at a specific point was randomly sampled with trilinear interpolation in the dataset from the first simulation. Six correlations between blood velocity, vessel proximity, and inflowing pO 2 were hypothesized. Variable models with correlated parameters were compared to each other and to a nonvariable, DOC-based model to evaluate the differences in simulated oxygen distributions and tumor radiosensitivities for different tumor sizes. Results: For tumors with radii ranging from 5 to 30 mm, the nonvariable DOC model tended to generate normal or log-normal oxygen distributions, with a cut-off at zero. The pO 2 distributions simulated with the six-variable DOC models were quite different from the distributions generated with the nonvariable DOC model; in the former case the variable models simulated oxygen distributions that were more similar to in vivo results found in the literature. For larger tumors, the oxygen distributions became truncated in the lower

  10. Accuracy and reproducibility of voxel based superimposition of cone beam computed tomography models on the anterior cranial base and the zygomatic arches.

    Science.gov (United States)

    Nada, Rania M; Maal, Thomas J J; Breuning, K Hero; Bergé, Stefaan J; Mostafa, Yehya A; Kuijpers-Jagtman, Anne Marie

    2011-02-09

    Superimposition of serial Cone Beam Computed Tomography (CBCT) scans has become a valuable tool for three dimensional (3D) assessment of treatment effects and stability. Voxel based image registration is a newly developed semi-automated technique for superimposition and comparison of two CBCT scans. The accuracy and reproducibility of CBCT superimposition on the anterior cranial base or the zygomatic arches using voxel based image registration was tested in this study. 16 pairs of 3D CBCT models were constructed from pre and post treatment CBCT scans of 16 adult dysgnathic patients. Each pair was registered on the anterior cranial base three times and on the left zygomatic arch twice. Following each superimposition, the mean absolute distances between the 2 models were calculated at 4 regions: anterior cranial base, forehead, left and right zygomatic arches. The mean distances between the models ranged from 0.2 to 0.37 mm (SD 0.08-0.16) for the anterior cranial base registration and from 0.2 to 0.45 mm (SD 0.09-0.27) for the zygomatic arch registration. The mean differences between the two registration zones ranged between 0.12 to 0.19 mm at the 4 regions. Voxel based image registration on both zones could be considered as an accurate and a reproducible method for CBCT superimposition. The left zygomatic arch could be used as a stable structure for the superimposition of smaller field of view CBCT scans where the anterior cranial base is not visible.

  11. Evaluating quantitative and qualitative models: An application for nationwide water erosion assessment in Ethiopia

    NARCIS (Netherlands)

    Sonneveld, B.G.J.S.; Keyzer, M.A.; Stroosnijder, L

    2011-01-01

    This paper tests the candidacy of one qualitative response model and two quantitative models for a nationwide water erosion hazard assessment in Ethiopia. After a descriptive comparison of model characteristics the study conducts a statistical comparison to evaluate the explanatory power of the

  12. Evaluating quantitative and qualitative models: an application for nationwide water erosion assessment in Ethiopia

    NARCIS (Netherlands)

    Sonneveld, B.G.J.S.; Keyzer, M.A.; Stroosnijder, L.

    2011-01-01

    This paper tests the candidacy of one qualitative response model and two quantitative models for a nationwide water erosion hazard assessment in Ethiopia. After a descriptive comparison of model characteristics the study conducts a statistical comparison to evaluate the explanatory power of the

  13. Assessment of a numerical model to reproduce event‐scale erosion and deposition distributions in a braided river

    Science.gov (United States)

    Measures, R.; Hicks, D. M.; Brasington, J.

    2016-01-01

    Abstract Numerical morphological modeling of braided rivers, using a physics‐based approach, is increasingly used as a technique to explore controls on river pattern and, from an applied perspective, to simulate the impact of channel modifications. This paper assesses a depth‐averaged nonuniform sediment model (Delft3D) to predict the morphodynamics of a 2.5 km long reach of the braided Rees River, New Zealand, during a single high‐flow event. Evaluation of model performance primarily focused upon using high‐resolution Digital Elevation Models (DEMs) of Difference, derived from a fusion of terrestrial laser scanning and optical empirical bathymetric mapping, to compare observed and predicted patterns of erosion and deposition and reach‐scale sediment budgets. For the calibrated model, this was supplemented with planform metrics (e.g., braiding intensity). Extensive sensitivity analysis of model functions and parameters was executed, including consideration of numerical scheme for bed load component calculations, hydraulics, bed composition, bed load transport and bed slope effects, bank erosion, and frequency of calculations. Total predicted volumes of erosion and deposition corresponded well to those observed. The difference between predicted and observed volumes of erosion was less than the factor of two that characterizes the accuracy of the Gaeuman et al. bed load transport formula. Grain size distributions were best represented using two φ intervals. For unsteady flows, results were sensitive to the morphological time scale factor. The approach of comparing observed and predicted morphological sediment budgets shows the value of using natural experiment data sets for model testing. Sensitivity results are transferable to guide Delft3D applications to other rivers. PMID:27708477

  14. Skills of General Circulation and Earth System Models in reproducing streamflow to the ocean: the case of Congo river

    Science.gov (United States)

    Santini, M.; Caporaso, L.

    2017-12-01

    Although the importance of water resources in the context of climate change, it is still difficult to correctly simulate the freshwater cycle over the land via General Circulation and Earth System Models (GCMs and ESMs). Existing efforts from the Climate Model Intercomparison Project 5 (CMIP5) were mainly devoted to the validation of atmospheric variables like temperature and precipitation, with low attention to discharge.Here we investigate the present-day performances of GCMs and ESMs participating to CMIP5 in simulating the discharge of the river Congo to the sea thanks to: i) the long-term availability of discharge data for the Kinshasa hydrological station representative of more than 95% of the water flowing in the whole catchment; and ii) the River's still low influence by human intervention, which enables comparison with the (mostly) natural streamflow simulated within CMIP5.Our findings suggest how most of models appear overestimating the streamflow in terms of seasonal cycle, especially in the late winter and spring, while overestimation and variability across models are lower in late summer. Weighted ensemble means are also calculated, based on simulations' performances given by several metrics, showing some improvements of results.Although simulated inter-monthly and inter-annual percent anomalies do not appear significantly different from those in observed data, when translated into well consolidated indicators of drought attributes (frequency, magnitude, timing, duration), usually adopted for more immediate communication to stakeholders and decision makers, such anomalies can be misleading.These inconsistencies produce incorrect assessments towards water management planning and infrastructures (e.g. dams or irrigated areas), especially if models are used instead of measurements, as in case of ungauged basins or for basins with insufficient data, as well as when relying on models for future estimates without a preliminary quantification of model biases.

  15. Assessment of a numerical model to reproduce event-scale erosion and deposition distributions in a braided river

    Science.gov (United States)

    Williams, R. D.; Measures, R.; Hicks, D. M.; Brasington, J.

    2016-08-01

    Numerical morphological modeling of braided rivers, using a physics-based approach, is increasingly used as a technique to explore controls on river pattern and, from an applied perspective, to simulate the impact of channel modifications. This paper assesses a depth-averaged nonuniform sediment model (Delft3D) to predict the morphodynamics of a 2.5 km long reach of the braided Rees River, New Zealand, during a single high-flow event. Evaluation of model performance primarily focused upon using high-resolution Digital Elevation Models (DEMs) of Difference, derived from a fusion of terrestrial laser scanning and optical empirical bathymetric mapping, to compare observed and predicted patterns of erosion and deposition and reach-scale sediment budgets. For the calibrated model, this was supplemented with planform metrics (e.g., braiding intensity). Extensive sensitivity analysis of model functions and parameters was executed, including consideration of numerical scheme for bed load component calculations, hydraulics, bed composition, bed load transport and bed slope effects, bank erosion, and frequency of calculations. Total predicted volumes of erosion and deposition corresponded well to those observed. The difference between predicted and observed volumes of erosion was less than the factor of two that characterizes the accuracy of the Gaeuman et al. bed load transport formula. Grain size distributions were best represented using two φ intervals. For unsteady flows, results were sensitive to the morphological time scale factor. The approach of comparing observed and predicted morphological sediment budgets shows the value of using natural experiment data sets for model testing. Sensitivity results are transferable to guide Delft3D applications to other rivers.

  16. An integrated qualitative and quantitative modeling framework for computer‐assisted HAZOP studies

    DEFF Research Database (Denmark)

    Wu, Jing; Zhang, Laibin; Hu, Jinqiu

    2014-01-01

    , objectives, and goals on different abstraction levels. Based on this abstraction, qualitative functional models are constructed for the process. Next MFM‐specified causal rules are extended with systems specific features to enable proper reasoning. Finally, systematic HAZOP analysis is performed to identify...... safety critical operations, its causes and consequences. The outcome is a qualitative hazard analysis of selected process deviations from normal operations and their consequences as input to a traditional HAZOP table. The list of unacceptable high risk deviations identified by the qualitative HAZOP...

  17. Repeatability and Reproducibility of Corneal Biometric Measurements Using the Visante Omni and a Rabbit Experimental Model of Post-Surgical Corneal Ectasia

    Science.gov (United States)

    Liu, Yu-Chi; Konstantopoulos, Aris; Riau, Andri K.; Bhayani, Raj; Lwin, Nyein C.; Teo, Ericia Pei Wen; Yam, Gary Hin Fai; Mehta, Jodhbir S.

    2015-01-01

    Purpose: To investigate the repeatability and reproducibility of the Visante Omni topography in obtaining topography measurements of rabbit corneas and to develop a post-surgical model of corneal ectasia. Methods: Eight rabbits were used to study the repeatability and reproducibility by assessing the intra- and interobserver bias and limits of agreement. Another nine rabbits underwent different diopters (D) of laser in situ keratosmileusis (LASIK) were used for the development of ectasia model. All eyes were examined with the Visante Omni, and corneal ultrastructure were evaluated with transmission electron microscopy (TEM). Results: There was no significant intra- or interobserver difference for mean steep and flat keratometry (K) values of simulated K, anterior, and posterior elevation measurements. Eyes underwent −5 D LASIK had a significant increase in mean amplitude of astigmatism and posterior surface elevation with time (P for trend corneal ectasia that was gradual in development and simulated the human condition. Translational Relevance: The results provide the foundations for the future evaluation of novel treatment modalities for post-surgical ectasia and keratoconus. PMID:25938004

  18. A Reliable and Reproducible Model for Assessing the Effect of Different Concentrations of α-Solanine on Rat Bone Marrow Mesenchymal Stem Cells

    Directory of Open Access Journals (Sweden)

    Adriana Ordóñez-Vásquez

    2017-01-01

    Full Text Available Αlpha-solanine (α-solanine is a glycoalkaloid present in potato (Solanum tuberosum. It has been of particular interest because of its toxicity and potential teratogenic effects that include abnormalities of the central nervous system, such as exencephaly, encephalocele, and anophthalmia. Various types of cell culture have been used as experimental models to determine the effect of α-solanine on cell physiology. The morphological changes in the mesenchymal stem cell upon exposure to α-solanine have not been established. This study aimed to describe a reliable and reproducible model for assessing the structural changes induced by exposure of mouse bone marrow mesenchymal stem cells (MSCs to different concentrations of α-solanine for 24 h. The results demonstrate that nonlethal concentrations of α-solanine (2–6 μM changed the morphology of the cells, including an increase in the number of nucleoli, suggesting elevated protein synthesis, and the formation of spicules. In addition, treatment with α-solanine reduced the number of adherent cells and the formation of colonies in culture. Immunophenotypic characterization and staining of MSCs are proposed as a reproducible method that allows description of cells exposed to the glycoalkaloid, α-solanine.

  19. Qualitative mathematics for the social sciences mathematical models for research on cultural dynamics

    CERN Document Server

    Rudolph, Lee

    2012-01-01

    In this book Lee Rudolph brings together international contributors who combine psychological and mathematical perspectives to analyse how qualitative mathematics can be used to create models of social and psychological processes. Bridging the gap between the fields with an imaginative and stimulating collection of contributed chapters, the volume updates the current research on the subject, which until now has been rather limited, focussing largely on the use of statistics. Qualitative Mathematics for the Social Sciences contains a variety of useful illustrative figures, in

  20. Attempting to train a digital human model to reproduce human subject reach capabilities in an ejection seat aircraft

    NARCIS (Netherlands)

    Zehner, G.F.; Hudson, J.A.; Oudenhuijzen, A.

    2006-01-01

    From 1997 through 2002, the Air Force Research Lab and TNO Defence, Security and Safety (Business Unit Human Factors) were involved in a series of tests to quantify the accuracy of five Human Modeling Systems (HMSs) in determining accommodation limits of ejection seat aircraft. The results of these

  1. Isokinetic eccentric exercise as a model to induce and reproduce pathophysiological alterations related to delayed onset muscle soreness

    DEFF Research Database (Denmark)

    Lund, Henrik; Vestergaard-Poulsen, P; Kanstrup, I.L.

    1998-01-01

    Physiological alterations following unaccustomed eccentric exercise in an isokinetic dynamometer of the right m. quadriceps until exhaustion were studied, in order to create a model in which the physiological responses to physiotherapy could be measured. In experiment I (exp. I), seven selected p...

  2. Developing a Collection of Composable Data Translation Software Units to Improve Efficiency and Reproducibility in Ecohydrologic Modeling Workflows

    Science.gov (United States)

    Olschanowsky, C.; Flores, A. N.; FitzGerald, K.; Masarik, M. T.; Rudisill, W. J.; Aguayo, M.

    2017-12-01

    Dynamic models of the spatiotemporal evolution of water, energy, and nutrient cycling are important tools to assess impacts of climate and other environmental changes on ecohydrologic systems. These models require spatiotemporally varying environmental forcings like precipitation, temperature, humidity, windspeed, and solar radiation. These input data originate from a variety of sources, including global and regional weather and climate models, global and regional reanalysis products, and geostatistically interpolated surface observations. Data translation measures, often subsetting in space and/or time and transforming and converting variable units, represent a seemingly mundane, but critical step in the application workflows. Translation steps can introduce errors, misrepresentations of data, slow execution time, and interrupt data provenance. We leverage a workflow that subsets a large regional dataset derived from the Weather Research and Forecasting (WRF) model and prepares inputs to the Parflow integrated hydrologic model to demonstrate the impact translation tool software quality on scientific workflow results and performance. We propose that such workflows will benefit from a community approved collection of data transformation components. The components should be self-contained composable units of code. This design pattern enables automated parallelization and software verification, improving performance and reliability. Ensuring that individual translation components are self-contained and target minute tasks increases reliability. The small code size of each component enables effective unit and regression testing. The components can be automatically composed for efficient execution. An efficient data translation framework should be written to minimize data movement. Composing components within a single streaming process reduces data movement. Each component will typically have a low arithmetic intensity, meaning that it requires about the same number of

  3. Synchronized mammalian cell culture: part II--population ensemble modeling and analysis for development of reproducible processes.

    Science.gov (United States)

    Jandt, Uwe; Barradas, Oscar Platas; Pörtner, Ralf; Zeng, An-Ping

    2015-01-01

    The consideration of inherent population inhomogeneities of mammalian cell cultures becomes increasingly important for systems biology study and for developing more stable and efficient processes. However, variations of cellular properties belonging to different sub-populations and their potential effects on cellular physiology and kinetics of culture productivity under bioproduction conditions have not yet been much in the focus of research. Culture heterogeneity is strongly determined by the advance of the cell cycle. The assignment of cell-cycle specific cellular variations to large-scale process conditions can be optimally determined based on the combination of (partially) synchronized cultivation under otherwise physiological conditions and subsequent population-resolved model adaptation. The first step has been achieved using the physical selection method of countercurrent flow centrifugal elutriation, recently established in our group for different mammalian cell lines which is presented in Part I of this paper series. In this second part, we demonstrate the successful adaptation and application of a cell-cycle dependent population balance ensemble model to describe and understand synchronized bioreactor cultivations performed with two model mammalian cell lines, AGE1.HNAAT and CHO-K1. Numerical adaptation of the model to experimental data allows for detection of phase-specific parameters and for determination of significant variations between different phases and different cell lines. It shows that special care must be taken with regard to the sampling frequency in such oscillation cultures to minimize phase shift (jitter) artifacts. Based on predictions of long-term oscillation behavior of a culture depending on its start conditions, optimal elutriation setup trade-offs between high cell yields and high synchronization efficiency are proposed. © 2014 American Institute of Chemical Engineers.

  4. Preserve specimens for reproducibility

    Czech Academy of Sciences Publication Activity Database

    Krell, F.-T.; Klimeš, Petr; Rocha, L. A.; Fikáček, M.; Miller, S. E.

    2016-01-01

    Roč. 539, č. 7628 (2016), s. 168 ISSN 0028-0836 Institutional support: RVO:60077344 Keywords : reproducibility * specimen * biodiversity Subject RIV: EH - Ecology, Behaviour Impact factor: 40.137, year: 2016 http://www.nature.com/nature/journal/v539/n7628/full/539168b.html

  5. Representing and managing uncertainty in qualitative ecological models

    NARCIS (Netherlands)

    Nuttle, T.; Bredeweg, B.; Salles, P.; Neumann, M.

    2009-01-01

    Ecologists and decision makers need ways to understand systems, test ideas, and make predictions and explanations about systems. However, uncertainty about causes and effects of processes and parameter values is pervasive in models of ecological systems. Uncertainty associated with incomplete

  6. Minimum Information about a Cardiac Electrophysiology Experiment (MICEE): Standardised Reporting for Model Reproducibility, Interoperability, and Data Sharing

    Science.gov (United States)

    Quinn, TA; Granite, S; Allessie, MA; Antzelevitch, C; Bollensdorff, C; Bub, G; Burton, RAB; Cerbai, E; Chen, PS; Delmar, M; DiFrancesco, D; Earm, YE; Efimov, IR; Egger, M; Entcheva, E; Fink, M; Fischmeister, R; Franz, MR; Garny, A; Giles, WR; Hannes, T; Harding, SE; Hunter, PJ; Iribe, G; Jalife, J; Johnson, CR; Kass, RS; Kodama, I; Koren, G; Lord, P; Markhasin, VS; Matsuoka, S; McCulloch, AD; Mirams, GR; Morley, GE; Nattel, S; Noble, D; Olesen, SP; Panfilov, AV; Trayanova, NA; Ravens, U; Richard, S; Rosenbaum, DS; Rudy, Y; Sachs, F; Sachse, FB; Saint, DA; Schotten, U; Solovyova, O; Taggart, P; Tung, L; Varró, A; Volders, PG; Wang, K; Weiss, JN; Wettwer, E; White, E; Wilders, R; Winslow, RL; Kohl, P

    2011-01-01

    Cardiac experimental electrophysiology is in need of a well-defined Minimum Information Standard for recording, annotating, and reporting experimental data. As a step toward establishing this, we present a draft standard, called Minimum Information about a Cardiac Electrophysiology Experiment (MICEE). The ultimate goal is to develop a useful tool for cardiac electrophysiologists which facilitates and improves dissemination of the minimum information necessary for reproduction of cardiac electrophysiology research, allowing for easier comparison and utilisation of findings by others. It is hoped that this will enhance the integration of individual results into experimental, computational, and conceptual models. In its present form, this draft is intended for assessment and development by the research community. We invite the reader to join this effort, and, if deemed productive, implement the Minimum Information about a Cardiac Electrophysiology Experiment standard in their own work. PMID:21745496

  7. A qualitative model of the salmon life cycle in the context of river rehabilitation

    NARCIS (Netherlands)

    Noble, R.A.A.; Bredeweg, B.; Linnebank, F.; Salles, P.; Cowx, I.G.; Žabkar, J.; Bratko, I.

    2009-01-01

    A qualitative model was developed in Garp3 to capture and formalise knowledge about river rehabilitation and the management of an Atlantic salmon population. The model integrates information about the ecology of the salmon life cycle, the environmental factors that may limit the survival of key life

  8. Learning to Act: Qualitative Learning of Deterministic Action Models

    DEFF Research Database (Denmark)

    Bolander, Thomas; Gierasimczuk, Nina

    2017-01-01

    in the limit (inconclusive convergence to the right action model). We show that deterministic actions are finitely identifiable, while arbitrary (non-deterministic) actions require more learning power—they are identifiable in the limit. We then move on to a particular learning method, i.e. learning via update......, which proceeds via restriction of a space of events within a learning-specific action model. We show how this method can be adapted to learn conditional and unconditional deterministic action models. We propose update learning mechanisms for the afore mentioned classes of actions and analyse...... their computational complexity. Finally, we study a parametrized learning method which makes use of the upper bound on the number of propositions relevant for a given learning scenario. We conclude with describing related work and numerous directions of further work....

  9. Reproducibility of haemodynamical simulations in a subject-specific stented aneurysm model--a report on the Virtual Intracranial Stenting Challenge 2007.

    Science.gov (United States)

    Radaelli, A G; Augsburger, L; Cebral, J R; Ohta, M; Rüfenacht, D A; Balossino, R; Benndorf, G; Hose, D R; Marzo, A; Metcalfe, R; Mortier, P; Mut, F; Reymond, P; Socci, L; Verhegghe, B; Frangi, A F

    2008-07-19

    This paper presents the results of the Virtual Intracranial Stenting Challenge (VISC) 2007, an international initiative whose aim was to establish the reproducibility of state-of-the-art haemodynamical simulation techniques in subject-specific stented models of intracranial aneurysms (IAs). IAs are pathological dilatations of the cerebral artery walls, which are associated with high mortality and morbidity rates due to subarachnoid haemorrhage following rupture. The deployment of a stent as flow diverter has recently been indicated as a promising treatment option, which has the potential to protect the aneurysm by reducing the action of haemodynamical forces and facilitating aneurysm thrombosis. The direct assessment of changes in aneurysm haemodynamics after stent deployment is hampered by limitations in existing imaging techniques and currently requires resorting to numerical simulations. Numerical simulations also have the potential to assist in the personalized selection of an optimal stent design prior to intervention. However, from the current literature it is difficult to assess the level of technological advancement and the reproducibility of haemodynamical predictions in stented patient-specific models. The VISC 2007 initiative engaged in the development of a multicentre-controlled benchmark to analyse differences induced by diverse grid generation and computational fluid dynamics (CFD) technologies. The challenge also represented an opportunity to provide a survey of available technologies currently adopted by international teams from both academic and industrial institutions for constructing computational models of stented aneurysms. The results demonstrate the ability of current strategies in consistently quantifying the performance of three commercial intracranial stents, and contribute to reinforce the confidence in haemodynamical simulation, thus taking a step forward towards the introduction of simulation tools to support diagnostics and

  10. Accuracy and reproducibility of voxel based superimposition of cone beam computed tomography models on the anterior cranial base and the zygomatic arches.

    Directory of Open Access Journals (Sweden)

    Rania M Nada

    Full Text Available Superimposition of serial Cone Beam Computed Tomography (CBCT scans has become a valuable tool for three dimensional (3D assessment of treatment effects and stability. Voxel based image registration is a newly developed semi-automated technique for superimposition and comparison of two CBCT scans. The accuracy and reproducibility of CBCT superimposition on the anterior cranial base or the zygomatic arches using voxel based image registration was tested in this study. 16 pairs of 3D CBCT models were constructed from pre and post treatment CBCT scans of 16 adult dysgnathic patients. Each pair was registered on the anterior cranial base three times and on the left zygomatic arch twice. Following each superimposition, the mean absolute distances between the 2 models were calculated at 4 regions: anterior cranial base, forehead, left and right zygomatic arches. The mean distances between the models ranged from 0.2 to 0.37 mm (SD 0.08-0.16 for the anterior cranial base registration and from 0.2 to 0.45 mm (SD 0.09-0.27 for the zygomatic arch registration. The mean differences between the two registration zones ranged between 0.12 to 0.19 mm at the 4 regions. Voxel based image registration on both zones could be considered as an accurate and a reproducible method for CBCT superimposition. The left zygomatic arch could be used as a stable structure for the superimposition of smaller field of view CBCT scans where the anterior cranial base is not visible.

  11. The operator model as a framework of research on errors and temporal, qualitative and analogical reasoning

    International Nuclear Information System (INIS)

    Decortis, F.; Drozdowicz, B.; Masson, M.

    1990-01-01

    In this paper the needs and requirements for developing a cognitive model of a human operator are discussed and the computer architecture, currently being developed, is described. Given the approach taken, namely the division of the problem into specialised tasks within an area and using the architecture chosen, it is possible to build independently several cognitive and psychological models such as errors and stress models, as well as models of temporal, qualitative and an analogical reasoning. (author)

  12. The spruce budworm and forest: a qualitative comparison of ODE and Boolean models

    Directory of Open Access Journals (Sweden)

    Raina Robeva

    2016-01-01

    Full Text Available Boolean and polynomial models of biological systems have emerged recently as viable companions to differential equations models. It is not immediately clear however whether such models are capable of capturing the multi-stable behaviour of certain biological systems: this behaviour is often sensitive to changes in the values of the model parameters, while Boolean and polynomial models are qualitative in nature. In the past few years, Boolean models of gene regulatory systems have been shown to capture multi-stability at the molecular level, confirming that such models can be used to obtain information about the system’s qualitative dynamics when precise information regarding its parameters may not be available. In this paper, we examine Boolean approximations of a classical ODE model of budworm outbreaks in a forest and show that these models exhibit a qualitative behaviour consistent with that derived from the ODE models. In particular, we demonstrate that these models can capture the bistable nature of insect population outbreaks, thus showing that Boolean models can be successfully utilized beyond the molecular level.

  13. Unicriterion Model: A Qualitative Decision Making Method That Promotes Ethics

    Directory of Open Access Journals (Sweden)

    Fernando Guilherme Silvano Lobo Pimentel

    2011-06-01

    Full Text Available Management decision making methods frequently adopt quantitativemodels of several criteria that bypass the question of whysome criteria are considered more important than others, whichmakes more difficult the task of delivering a transparent viewof preference structure priorities that might promote ethics andlearning and serve as a basis for future decisions. To tackle thisparticular shortcoming of usual methods, an alternative qualitativemethodology of aggregating preferences based on the rankingof criteria is proposed. Such an approach delivers a simpleand transparent model for the solution of each preference conflictfaced during the management decision making process. Themethod proceeds by breaking the decision problem into ‘two criteria– two alternatives’ scenarios, and translating the problem ofchoice between alternatives to a problem of choice between criteriawhenever appropriate. The unicriterion model method is illustratedby its application in a car purchase and a house purchasedecision problem.

  14. Reproducibility of ultrasonic testing

    International Nuclear Information System (INIS)

    Lecomte, J.-C.; Thomas, Andre; Launay, J.-P.; Martin, Pierre

    The reproducibility of amplitude quotations for both artificial and natural reflectors was studied for several combinations of instrument/search unit, all being of the same type. This study shows that in industrial inspection if a range of standardized equipment is used, a margin of error of about 6 decibels has to be taken into account (confidence interval of 95%). This margin is about 4 to 5 dB for natural or artificial defects located in the central area and about 6 to 7 dB for artificial defects located on the back surface. This lack of reproducibility seems to be attributable first to the search unit and then to the instrument and operator. These results were confirmed by analysis of calibration data obtained from 250 tests performed by 25 operators under shop conditions. The margin of error was higher than the 6 dB obtained in the study [fr

  15. Retrospective Correction of Physiological Noise: Impact on Sensitivity, Specificity, and Reproducibility of Resting-State Functional Connectivity in a Reading Network Model.

    Science.gov (United States)

    Krishnamurthy, Venkatagiri; Krishnamurthy, Lisa C; Schwam, Dina M; Ealey, Ashley; Shin, Jaemin; Greenberg, Daphne; Morris, Robin D

    2018-03-01

    It is well accepted that physiological noise (PN) obscures the detection of neural fluctuations in resting-state functional connectivity (rsFC) magnetic resonance imaging. However, a clear consensus for an optimal PN correction (PNC) methodology and how it can impact the rsFC signal characteristics is still lacking. In this study, we probe the impact of three PNC methods: RETROICOR: (Glover et al., 2000 ), ANATICOR: (Jo et al., 2010 ), and RVTMBPM: (Bianciardi et al., 2009 ). Using a reading network model, we systematically explore the effects of PNC optimization on sensitivity, specificity, and reproducibility of rsFC signals. In terms of specificity, ANATICOR was found to be effective in removing local white matter (WM) fluctuations and also resulted in aggressive removal of expected cortical-to-subcortical functional connections. The ability of RETROICOR to remove PN was equivalent to removal of simulated random PN such that it artificially inflated the connection strength, thereby decreasing sensitivity. RVTMBPM maintained specificity and sensitivity by balanced removal of vasodilatory PN and local WM nuisance edges. Another aspect of this work was exploring the effects of PNC on identifying reading group differences. Most PNC methods accounted for between-subject PN variability resulting in reduced intersession reproducibility. This effect facilitated the detection of the most consistent group differences. RVTMBPM was most effective in detecting significant group differences due to its inherent sensitivity to removing spatially structured and temporally repeating PN arising from dense vasculature. Finally, results suggest that combining all three PNC resulted in "overcorrection" by removing signal along with noise.

  16. A Qualitative Study of Parental Modeling and Social Support for Physical Activity in Underserved Adolescents

    Science.gov (United States)

    Wright, Marcie S.; Wilson, Dawn K.; Griffin, Sarah; Evans, Alexandra

    2010-01-01

    This study obtained qualitative data to assess how parental role modeling and parental social support influence physical activity in underserved (minority, low-income) adolescents. Fifty-two adolescents (22 males, 30 females; ages 10-14 years, 85% African-American) participated in a focus group (6-10 per group, same gender). Focus groups were…

  17. Disease management projects and the Chronic CareModel in action: Baseline qualitative research

    NARCIS (Netherlands)

    B.J. Hipple Walters (Bethany); S.A. Adams (Samantha); A.P. Nieboer (Anna); R.A. Bal (Roland)

    2012-01-01

    textabstractBackground: Disease management programs, especially those based on the Chronic Care Model (CCM),are increasingly common in the Netherlands. While disease management programs have beenwell-researched quantitatively and economically, less qualitative research has been done. Theoverall aim

  18. Measurements of boat motion in waves at Durban harbour for qualitative validation of motion model

    CSIR Research Space (South Africa)

    Mosikare, OR

    2010-09-01

    Full Text Available in Waves at Durban Harbour for Qualitative Validation of Motion Model O.R. Mosikare1,2, N.J. Theron1, W. Van der Molen 1 University of Pretoria, South Africa, 0001 2Council for Scientific and Industrial Research, Meiring Naude Rd, Brummeria, 0001...

  19. Teaching Qualitative Research for Human Services Students: A Three-Phase Model

    Science.gov (United States)

    Goussinsky, Ruhama; Reshef, Arie; Yanay-Ventura, Galit; Yassour-Borochowitz, Dalit

    2011-01-01

    Qualitative research is an inherent part of the human services profession, since it emphasizes the great and multifaceted complexity characterizing human experience and the sociocultural context in which humans act. In the department of human services at Emek Yezreel College, Israel, we have developed a three-phase model to ensure a relatively…

  20. Reproducible research in palaeomagnetism

    Science.gov (United States)

    Lurcock, Pontus; Florindo, Fabio

    2015-04-01

    The reproducibility of research findings is attracting increasing attention across all scientific disciplines. In palaeomagnetism as elsewhere, computer-based analysis techniques are becoming more commonplace, complex, and diverse. Analyses can often be difficult to reproduce from scratch, both for the original researchers and for others seeking to build on the work. We present a palaeomagnetic plotting and analysis program designed to make reproducibility easier. Part of the problem is the divide between interactive and scripted (batch) analysis programs. An interactive desktop program with a graphical interface is a powerful tool for exploring data and iteratively refining analyses, but usually cannot operate without human interaction. This makes it impossible to re-run an analysis automatically, or to integrate it into a larger automated scientific workflow - for example, a script to generate figures and tables for a paper. In some cases the parameters of the analysis process itself are not saved explicitly, making it hard to repeat or improve the analysis even with human interaction. Conversely, non-interactive batch tools can be controlled by pre-written scripts and configuration files, allowing an analysis to be 'replayed' automatically from the raw data. However, this advantage comes at the expense of exploratory capability: iteratively improving an analysis entails a time-consuming cycle of editing scripts, running them, and viewing the output. Batch tools also tend to require more computer expertise from their users. PuffinPlot is a palaeomagnetic plotting and analysis program which aims to bridge this gap. First released in 2012, it offers both an interactive, user-friendly desktop interface and a batch scripting interface, both making use of the same core library of palaeomagnetic functions. We present new improvements to the program that help to integrate the interactive and batch approaches, allowing an analysis to be interactively explored and refined

  1. Towards Reproducibility in Computational Hydrology

    Science.gov (United States)

    Hutton, Christopher; Wagener, Thorsten; Freer, Jim; Han, Dawei; Duffy, Chris; Arheimer, Berit

    2017-04-01

    Reproducibility is a foundational principle in scientific research. The ability to independently re-run an experiment helps to verify the legitimacy of individual findings, and evolve (or reject) hypotheses and models of how environmental systems function, and move them from specific circumstances to more general theory. Yet in computational hydrology (and in environmental science more widely) the code and data that produces published results are not regularly made available, and even if they are made available, there remains a multitude of generally unreported choices that an individual scientist may have made that impact the study result. This situation strongly inhibits the ability of our community to reproduce and verify previous findings, as all the information and boundary conditions required to set up a computational experiment simply cannot be reported in an article's text alone. In Hutton et al 2016 [1], we argue that a cultural change is required in the computational hydrological community, in order to advance and make more robust the process of knowledge creation and hypothesis testing. We need to adopt common standards and infrastructures to: (1) make code readable and re-useable; (2) create well-documented workflows that combine re-useable code together with data to enable published scientific findings to be reproduced; (3) make code and workflows available, easy to find, and easy to interpret, using code and code metadata repositories. To create change we argue for improved graduate training in these areas. In this talk we reflect on our progress in achieving reproducible, open science in computational hydrology, which are relevant to the broader computational geoscience community. In particular, we draw on our experience in the Switch-On (EU funded) virtual water science laboratory (http://www.switch-on-vwsl.eu/participate/), which is an open platform for collaboration in hydrological experiments (e.g. [2]). While we use computational hydrology as

  2. Opening Reproducible Research

    Science.gov (United States)

    Nüst, Daniel; Konkol, Markus; Pebesma, Edzer; Kray, Christian; Klötgen, Stephanie; Schutzeichel, Marc; Lorenz, Jörg; Przibytzin, Holger; Kussmann, Dirk

    2016-04-01

    Open access is not only a form of publishing such that research papers become available to the large public free of charge, it also refers to a trend in science that the act of doing research becomes more open and transparent. When science transforms to open access we not only mean access to papers, research data being collected, or data being generated, but also access to the data used and the procedures carried out in the research paper. Increasingly, scientific results are generated by numerical manipulation of data that were already collected, and may involve simulation experiments that are completely carried out computationally. Reproducibility of research findings, the ability to repeat experimental procedures and confirm previously found results, is at the heart of the scientific method (Pebesma, Nüst and Bivand, 2012). As opposed to the collection of experimental data in labs or nature, computational experiments lend themselves very well for reproduction. Some of the reasons why scientists do not publish data and computational procedures that allow reproduction will be hard to change, e.g. privacy concerns in the data, fear for embarrassment or of losing a competitive advantage. Others reasons however involve technical aspects, and include the lack of standard procedures to publish such information and the lack of benefits after publishing them. We aim to resolve these two technical aspects. We propose a system that supports the evolution of scientific publications from static papers into dynamic, executable research documents. The DFG-funded experimental project Opening Reproducible Research (ORR) aims for the main aspects of open access, by improving the exchange of, by facilitating productive access to, and by simplifying reuse of research results that are published over the Internet. Central to the project is a new form for creating and providing research results, the executable research compendium (ERC), which not only enables third parties to

  3. Inhibition of basophil activation by histamine: a sensitive and reproducible model for the study of the biological activity of high dilutions.

    Science.gov (United States)

    Sainte-Laudy, J; Belon, Ph

    2009-10-01

    (another human basophil activation marker). Results were expressed in mean fluorescence intensity of the CD203c positive population (MFI-CD203c) and an activation index calculated by an algorithm. For the mouse basophil model, histamine was measured spectrofluorimetrically. The main results obtained over 28 years of work was the demonstration of a reproducible inhibition of human basophil activation by high dilutions of histamine, the effect peaks in the range of 15-17CH. The effect was not significant when histamine was replaced by histidine (a histamine precursor) or cimetidine (histamine H2 receptor antagonist) was added to the incubation medium. These results were confirmed by flow cytometry. Using the latter technique, we also showed that 4-Methyl histamine (H2 agonist) induced a similar effect, in contrast to 1-Methyl histamine, an inactive histamine metabolite. Using the mouse model, we showed that histamine high dilutions, in the same range of dilutions, inhibited histamine release. Successively, using different models to study of human and murine basophil activation, we demonstrated that high dilutions of histamine, in the range of 15-17CH induce a reproducible biological effect. This phenomenon has been confirmed by a multi-center study using the HBDT model and by at least three independent laboratories by flow cytometry. The specificity of the observed effect was confirmed, versus the water controls at the same dilution level by the absence of biological activity of inactive compounds such as histidine and 1-Methyl histamine and by the reversibility of this effect in the presence of a histamine receptor H2 antagonist.

  4. A CFBPN Artificial Neural Network Model for Educational Qualitative Data Analyses: Example of Students' Attitudes Based on Kellerts' Typologies

    Science.gov (United States)

    Yorek, Nurettin; Ugulu, Ilker

    2015-01-01

    In this study, artificial neural networks are suggested as a model that can be "trained" to yield qualitative results out of a huge amount of categorical data. It can be said that this is a new approach applied in educational qualitative data analysis. In this direction, a cascade-forward back-propagation neural network (CFBPN) model was…

  5. COGNITIVE MODELING AS A METHOD OF QUALITATIVE ANALYSIS OF IT PROJECTS

    Directory of Open Access Journals (Sweden)

    Інна Ігорівна ОНИЩЕНКО

    2016-03-01

    Full Text Available The example project implementing automated CRM-system demonstrated the possibility and features of cognitive modeling in the qualitative analysis of project risks to determine their additional features. Proposed construction of cognitive models of project risks in information technology within the qualitative risk analysis, additional assessments as a method of ranking risk to characterize the relationship between them. The proposed cognitive model reflecting the relationship between the risk of IT project to assess the negative and the positive impact of certain risks for the remaining risks of project implementation of the automated CRM-system. The ability to influence the risk of a fact of other project risks can increase the priority of risk with low impact on results due to its relationship with other project risks.

  6. Biodiversity and soil quality in agroecosystems: the use of a qualitative multi-attribute model

    DEFF Research Database (Denmark)

    Cortet, J.; Bohanec, M.; Griffiths, B.

    2009-01-01

    In ecological impact assessment, special emphasis is put on soil biology and estimating soil quality from the observed biological parameters. The aim of this study is to propose a tool easy to use for scientists and decision makers for agroecosystems soil quality assessment using these biological...... parameters. This tool was developed as a collaboration between ECOGEN (www.ecogen.dk) soil experts and decision analysts. Methodologically, we have addressed this goal using model-based Decision Support Systems (DSS), taking the approach of qualitative multi-attribute modelling. The approach is based...... on developing various hierarchical multiattribute models that consist of qualitative attributes and utility (aggregation) functions, represented by decision rules. The assessment of soil quality is based on two main indicators: (1) soil diversity (assessed through microfauna, mesofauna and macrofauna richness...

  7. Modeling the alcoholic fermentation of xylose by Pichia stipitis using a qualitative reasoning approach

    Energy Technology Data Exchange (ETDEWEB)

    Guerrin, F. (INRA (Institut National de la Recherche Agronomique), Biometrics and Artificial Intelligence Station, 31 - Castanet-Tolosan (France)); Delgenes, J.P. (INRA, Biotechnological Lab. for Food Industry Environment, 11 - Narbonne (France)); Moletta, R. (INRA, Biotechnological Lab. for Food Industry Environment, 11 - Narbonne (France))

    1994-03-01

    Qualitative Reasoning is a set of Artificial Intelligence theories, methods, and techniques that provide an answer to modeling problems in domains in which one can have a clear notion of how a system is functioning without being able to express it as classical mathematical equations, and where is posed the problem of using jointly quantitative and qualitative data, as well as processing a big amount of complex knowledge. SIMAO ('a System to Interpret Measurements And Observations') is an attempt to deal with such problems. Although primarily devised for heterogeneous data interpretation in hydroecology, it was thought possible to use SIMAO in a wider context, like biotechnological processes. Starting from specific problems posed by a batch fermentation, the D-xylose conversion into ethanol by the yeast Pichia stipitis, this paper descibes how was built and used a SIMAO model aimed at predicting the fermentation issue from initial conditions, i.e. set-points values and substrate concentration. (orig.)

  8. The Development of a Qualitative Dynamic Attribute Value Model for Healthcare Institutes

    Science.gov (United States)

    Lee, Wan-I

    2010-01-01

    Background: Understanding customers has become an urgent topic for increasing competitiveness. The purpopse of the study was to develop a qualitative dynamic attribute value model which provides insight into the customers’ value for healthcare institute managers by conducting the initial open-ended questionnaire survey to select participants purposefully. Methods: A total number of 427 questionnaires was conducted in two hospitals in Taiwan (one district hospital with 635 beds and one academic hospital with 2495 beds) and 419 questionnaires were received in nine weeks. Then, apply qualitative in-depth interviews to explore customers’ perspective of values for building a model of partial differential equations. Results: This study concludes nine categories of value, including cost, equipment, physician background, physicain care, environment, timing arrangement, relationship, brand image and additional value, to construct objective network for customer value and qualitative dynamic attribute value model where the network shows the value process of loyalty development via its effect on customer satisfaction, customer relationship, customer loyalty and healthcare service. Conclusion: One set predicts the customer relationship based on comminent, including service quality, communication and empahty. As the same time, customer loyalty based on trust, involves buzz marketing, brand and image. Customer value of the current instance is useful for traversing original customer attributes and identifing customers on different service share. PMID:23113034

  9. The development of a qualitative dynamic attribute value model for healthcare institutes.

    Science.gov (United States)

    Lee, Wan-I

    2010-01-01

    Understanding customers has become an urgent topic for increasing competitiveness. The purpopse of the study was to develop a qualitative dynamic attribute value model which provides insight into the customers' value for healthcare institute managers by conducting the initial open-ended questionnaire survey to select participants purposefully. A total number of 427 questionnaires was conducted in two hospitals in Taiwan (one district hospital with 635 beds and one academic hospital with 2495 beds) and 419 questionnaires were received in nine weeks. Then, apply qualitative in-depth interviews to explore customers' perspective of values for building a model of partial differential equations. This study concludes nine categories of value, including cost, equipment, physician background, physicain care, environment, timing arrangement, relationship, brand image and additional value, to construct objective network for customer value and qualitative dynamic attribute value model where the network shows the value process of loyalty development via its effect on customer satisfaction, customer relationship, customer loyalty and healthcare service. One set predicts the customer relationship based on comminent, including service quality, communication and empahty. As the same time, customer loyalty based on trust, involves buzz marketing, brand and image. Customer value of the current instance is useful for traversing original customer attributes and identifing customers on different service share.

  10. A right to reproduce?

    Science.gov (United States)

    Emson, H E

    1992-10-31

    Conscious control of the environment by homo sapiens has brought almost total release from the controls of ecology that limit the population of all other species. After a mere 10,000 years, humans have brought the planet close to collapse, and all the debate in the world seems unlikely to save it. A combination of uncontrolled breeding and rapacity is propelling us down the slippery slope 1st envisioned by Malthus, dragging the rest of the planet along. Only the conscious control, and most likely voluntary, reimposition of controls on breeding will reduce the overgrowth of humans, and we have far to go in that direction. "According to the United Nations Universal Declaration of Human Rights (1948, articles 16[I] and 16 [III]), Men and women of full age without any limitation due to race, nationality or religion have the right to marry and to found a family ... the family is the natural and fundamental group unit of society." The rhetoric of rights without the balancing of responsibilities is wrong in health care, and even more wrong in the context of world population. The mind-set of dominance and exploitation over the rest of creation has meant human reluctance to admit participation in a system where every part is interdependent. We must balance the right to reproduce with it responsible use, valuing interdependence, understanding, and respect with a duty not to unbalance, damage, or destroy. It is long overdue that we discard every statement of right that is unmatched by the equivalent duty and responsibility.

  11. Qualitative and quantitative guidelines for the comparison of environmental model predictions

    International Nuclear Information System (INIS)

    Scott, M.

    1995-03-01

    The question of how to assess or compare predictions from a number of models is one of concern in the validation of models, in understanding the effects of different models and model parameterizations on model output, and ultimately in assessing model reliability. Comparison of model predictions with observed data is the basic tool of model validation while comparison of predictions amongst different models provides one measure of model credibility. The guidance provided here is intended to provide qualitative and quantitative approaches (including graphical and statistical techniques) to such comparisons for use within the BIOMOVS II project. It is hoped that others may find it useful. It contains little technical information on the actual methods but several references are provided for the interested reader. The guidelines are illustrated on data from the VAMP CB scenario. Unfortunately, these data do not permit all of the possible approaches to be demonstrated since predicted uncertainties were not provided. The questions considered are concerned with a) intercomparison of model predictions and b) comparison of model predictions with the observed data. A series of examples illustrating some of the different types of data structure and some possible analyses have been constructed. A bibliography of references on model validation is provided. It is important to note that the results of the various techniques discussed here, whether qualitative or quantitative, should not be considered in isolation. Overall model performance must also include an evaluation of model structure and formulation, i.e. conceptual model uncertainties, and results for performance measures must be interpreted in this context. Consider a number of models which are used to provide predictions of a number of quantities at a number of time points. In the case of the VAMP CB scenario, the results include predictions of total deposition of Cs-137 and time dependent concentrations in various

  12. An Exploratory Qualitative Study of the Proximal Goal Setting of Two Introductory Modeling Instruction Physics Students

    Science.gov (United States)

    Sawtelle, Vashti; Brewe, Eric; Kramer, Laird

    2009-11-01

    Proximal goal setting has been strongly linked to self-efficacy and often occurs in successful problem solving. A qualitative study, using both observations and interviews, investigated the problem-solving processes and the self-efficacy of two students enrolled in an introductory physics course that implemented Modeling Instruction at Florida International University. We found that the problem solving process could be divided into two main phases: the goal setting process and the self-efficacy feedback loop. Further, from the qualitative data, the goal setting process could not be isolated from its impact on the self-efficacy of the students. This relationship between the goal setting strategies within the problem-solving process and self-efficacy may be linked to the retention of students in physics. We present results of the study and its possible link to student retention.

  13. Osteolytica: An automated image analysis software package that rapidly measures cancer-induced osteolytic lesions in in vivo models with greater reproducibility compared to other commonly used methods.

    Science.gov (United States)

    Evans, H R; Karmakharm, T; Lawson, M A; Walker, R E; Harris, W; Fellows, C; Huggins, I D; Richmond, P; Chantry, A D

    2016-02-01

    Methods currently used to analyse osteolytic lesions caused by malignancies such as multiple myeloma and metastatic breast cancer vary from basic 2-D X-ray analysis to 2-D images of micro-CT datasets analysed with non-specialised image software such as ImageJ. However, these methods have significant limitations. They do not capture 3-D data, they are time-consuming and they often suffer from inter-user variability. We therefore sought to develop a rapid and reproducible method to analyse 3-D osteolytic lesions in mice with cancer-induced bone disease. To this end, we have developed Osteolytica, an image analysis software method featuring an easy to use, step-by-step interface to measure lytic bone lesions. Osteolytica utilises novel graphics card acceleration (parallel computing) and 3-D rendering to provide rapid reconstruction and analysis of osteolytic lesions. To evaluate the use of Osteolytica we analysed tibial micro-CT datasets from murine models of cancer-induced bone disease and compared the results to those obtained using a standard ImageJ analysis method. Firstly, to assess inter-user variability we deployed four independent researchers to analyse tibial datasets from the U266-NSG murine model of myeloma. Using ImageJ, inter-user variability between the bones was substantial (±19.6%), in contrast to using Osteolytica, which demonstrated minimal variability (±0.5%). Secondly, tibial datasets from U266-bearing NSG mice or BALB/c mice injected with the metastatic breast cancer cell line 4T1 were compared to tibial datasets from aged and sex-matched non-tumour control mice. Analyses by both Osteolytica and ImageJ showed significant increases in bone lesion area in tumour-bearing mice compared to control mice. These results confirm that Osteolytica performs as well as the current 2-D ImageJ osteolytic lesion analysis method. However, Osteolytica is advantageous in that it analyses over the entirety of the bone volume (as opposed to selected 2-D images), it

  14. Bio-logic builder: a non-technical tool for building dynamical, qualitative models.

    Science.gov (United States)

    Helikar, Tomáš; Kowal, Bryan; Madrahimov, Alex; Shrestha, Manish; Pedersen, Jay; Limbu, Kahani; Thapa, Ishwor; Rowley, Thaine; Satalkar, Rahul; Kochi, Naomi; Konvalina, John; Rogers, Jim A

    2012-01-01

    Computational modeling of biological processes is a promising tool in biomedical research. While a large part of its potential lies in the ability to integrate it with laboratory research, modeling currently generally requires a high degree of training in mathematics and/or computer science. To help address this issue, we have developed a web-based tool, Bio-Logic Builder, that enables laboratory scientists to define mathematical representations (based on a discrete formalism) of biological regulatory mechanisms in a modular and non-technical fashion. As part of the user interface, generalized "bio-logic" modules have been defined to provide users with the building blocks for many biological processes. To build/modify computational models, experimentalists provide purely qualitative information about a particular regulatory mechanisms as is generally found in the laboratory. The Bio-Logic Builder subsequently converts the provided information into a mathematical representation described with Boolean expressions/rules. We used this tool to build a number of dynamical models, including a 130-protein large-scale model of signal transduction with over 800 interactions, influenza A replication cycle with 127 species and 200+ interactions, and mammalian and budding yeast cell cycles. We also show that any and all qualitative regulatory mechanisms can be built using this tool.

  15. Qualitative models to predict impacts of human interventions in a wetland ecosystem

    Directory of Open Access Journals (Sweden)

    S. Loiselle

    2002-07-01

    Full Text Available The large shallow wetlands that dominate much of the South American continent are rich in biodiversity and complexity. Many of these undamaged ecosystems are presently being examined for their potential economic utility, putting pressure on local authorities and the conservation community to find ways of correctly utilising the available natural resources without compromising the ecosystem functioning and overall integrity. Contrary to many northern hemisphere ecosystems, there have been little long term ecological studies of these systems, leading to a lack of quantitative data on which to construct ecological or resource use models. As a result, decision makers, even well meaning ones, have difficulty in determining if particular economic activities can potentially cause significant damage to the ecosystem and how one should go about monitoring the impacts of such activities. While the direct impact of many activities is often known, the secondary indirect impacts are usually less clear and can depend on local ecological conditions.

    The use of qualitative models is a helpful tool to highlight potential feedback mechanisms and secondary effects of management action on ecosystem integrity. The harvesting of a single, apparently abundant, species can have indirect secondary effects on key trophic and abiotic compartments. In this paper, loop model analysis is used to qualitatively examine secondary effects of potential economic activities in a large wetland area in northeast Argentina, the Esteros del Ibera. Based on interaction with local actors together with observed ecological information, loop models were constructed to reflect relationships between biotic and abiotic compartments. A series of analyses were made to study the effect of different economic scenarios on key ecosystem compartments. Important impacts on key biotic compartments (phytoplankton, zooplankton, ichthyofauna, aquatic macrophytes and on the abiotic environment

  16. Qualitative models and experimental investigation of chaotic NOR gates and set/reset flip-flops

    Science.gov (United States)

    Rahman, Aminur; Jordan, Ian; Blackmore, Denis

    2018-01-01

    It has been observed through experiments and SPICE simulations that logical circuits based upon Chua's circuit exhibit complex dynamical behaviour. This behaviour can be used to design analogues of more complex logic families and some properties can be exploited for electronics applications. Some of these circuits have been modelled as systems of ordinary differential equations. However, as the number of components in newer circuits increases so does the complexity. This renders continuous dynamical systems models impractical and necessitates new modelling techniques. In recent years, some discrete dynamical models have been developed using various simplifying assumptions. To create a robust modelling framework for chaotic logical circuits, we developed both deterministic and stochastic discrete dynamical models, which exploit the natural recurrence behaviour, for two chaotic NOR gates and a chaotic set/reset flip-flop. This work presents a complete applied mathematical investigation of logical circuits. Experiments on our own designs of the above circuits are modelled and the models are rigorously analysed and simulated showing surprisingly close qualitative agreement with the experiments. Furthermore, the models are designed to accommodate dynamics of similarly designed circuits. This will allow researchers to develop ever more complex chaotic logical circuits with a simple modelling framework.

  17. Production process reproducibility and product quality consistency of transient gene expression in HEK293 cells with anti-PD1 antibody as the model protein.

    Science.gov (United States)

    Ding, Kai; Han, Lei; Zong, Huifang; Chen, Junsheng; Zhang, Baohong; Zhu, Jianwei

    2017-03-01

    Demonstration of reproducibility and consistency of process and product quality is one of the most crucial issues in using transient gene expression (TGE) technology for biopharmaceutical development. In this study, we challenged the production consistency of TGE by expressing nine batches of recombinant IgG antibody in human embryonic kidney 293 cells to evaluate reproducibility including viable cell density, viability, apoptotic status, and antibody yield in cell culture supernatant. Product quality including isoelectric point, binding affinity, secondary structure, and thermal stability was assessed as well. In addition, major glycan forms of antibody from different batches of production were compared to demonstrate glycosylation consistency. Glycan compositions of the antibody harvested at different time periods were also measured to illustrate N-glycan distribution over the culture time. From the results, it has been demonstrated that different TGE batches are reproducible from lot to lot in overall cell growth, product yield, and product qualities including isoelectric point, binding affinity, secondary structure, and thermal stability. Furthermore, major N-glycan compositions are consistent among different TGE batches and conserved during cell culture time.

  18. Integrated decision-making about housing, energy and wellbeing: a qualitative system dynamics model.

    Science.gov (United States)

    Macmillan, Alexandra; Davies, Michael; Shrubsole, Clive; Luxford, Naomi; May, Neil; Chiu, Lai Fong; Trutnevyte, Evelina; Bobrova, Yekatherina; Chalabi, Zaid

    2016-03-08

    The UK government has an ambitious goal to reduce carbon emissions from the housing stock through energy efficiency improvements. This single policy goal is a strong driver for change in the housing system, but comes with positive and negative "unintended consequences" across a broad range of outcomes for health, equity and environmental sustainability. The resulting policies are also already experiencing under-performance through a failure to consider housing as a complex system. This research aimed to move from considering disparate objectives of housing policies in isolation to mapping the links between environmental, economic, social and health outcomes as a complex system. We aimed to support a broad range of housing policy stakeholders to improve their understanding of housing as a complex system through a collaborative learning process. We used participatory system dynamics modelling to develop a qualitative causal theory linking housing, energy and wellbeing. Qualitative interviews were followed by two interactive workshops to develop the model, involving representatives from national and local government, housing industries, non-government organisations, communities and academia. More than 50 stakeholders from 37 organisations participated. The process resulted in a shared understanding of wellbeing as it relates to housing; an agreed set of criteria against which to assess to future policy options; and a comprehensive set of causal loop diagrams describing the housing, energy and wellbeing system. The causal loop diagrams cover seven interconnected themes: community connection and quality of neighbourhoods; energy efficiency and climate change; fuel poverty and indoor temperature; household crowding; housing affordability; land ownership, value and development patterns; and ventilation and indoor air pollution. The collaborative learning process and the model have been useful for shifting the thinking of a wide range of housing stakeholders towards a more

  19. Avoiding and identifying errors in health technology assessment models: qualitative study and methodological review.

    Science.gov (United States)

    Chilcott, J; Tappenden, P; Rawdin, A; Johnson, M; Kaltenthaler, E; Paisley, S; Papaioannou, D; Shippam, A

    2010-05-01

    Health policy decisions must be relevant, evidence-based and transparent. Decision-analytic modelling supports this process but its role is reliant on its credibility. Errors in mathematical decision models or simulation exercises are unavoidable but little attention has been paid to processes in model development. Numerous error avoidance/identification strategies could be adopted but it is difficult to evaluate the merits of strategies for improving the credibility of models without first developing an understanding of error types and causes. The study aims to describe the current comprehension of errors in the HTA modelling community and generate a taxonomy of model errors. Four primary objectives are to: (1) describe the current understanding of errors in HTA modelling; (2) understand current processes applied by the technology assessment community for avoiding errors in development, debugging and critically appraising models for errors; (3) use HTA modellers' perceptions of model errors with the wider non-HTA literature to develop a taxonomy of model errors; and (4) explore potential methods and procedures to reduce the occurrence of errors in models. It also describes the model development process as perceived by practitioners working within the HTA community. A methodological review was undertaken using an iterative search methodology. Exploratory searches informed the scope of interviews; later searches focused on issues arising from the interviews. Searches were undertaken in February 2008 and January 2009. In-depth qualitative interviews were performed with 12 HTA modellers from academic and commercial modelling sectors. All qualitative data were analysed using the Framework approach. Descriptive and explanatory accounts were used to interrogate the data within and across themes and subthemes: organisation, roles and communication; the model development process; definition of error; types of model error; strategies for avoiding errors; strategies for

  20. Involving mental health service users in suicide-related research: a qualitative inquiry model.

    Science.gov (United States)

    Lees, David; Procter, Nicholas; Fassett, Denise; Handley, Christine

    2016-03-01

    To describe the research model developed and successfully deployed as part of a multi-method qualitative study investigating suicidal service-users' experiences of mental health nursing care. Quality mental health care is essential to limiting the occurrence and burden of suicide, however there is a lack of relevant research informing practice in this context. Research utilising first-person accounts of suicidality is of particular importance to expanding the existing evidence base. However, conducting ethical research to support this imperative is challenging. The model discussed here illustrates specific and more generally applicable principles for qualitative research regarding sensitive topics and involving potentially vulnerable service-users. Researching into mental health service users with first-person experience of suicidality requires stakeholder and institutional support, researcher competency, and participant recruitment, consent, confidentiality, support and protection. Research with service users into their experiences of sensitive issues such as suicidality can result in rich and valuable data, and may also provide positive experiences of collaboration and inclusivity. If challenges are not met, objectification and marginalisation of service-users may be reinforced, and limitations in the evidence base and service provision may be perpetuated.

  1. Qualitative Fault Isolation of Hybrid Systems: A Structural Model Decomposition-Based Approach

    Science.gov (United States)

    Bregon, Anibal; Daigle, Matthew; Roychoudhury, Indranil

    2016-01-01

    Quick and robust fault diagnosis is critical to ensuring safe operation of complex engineering systems. A large number of techniques are available to provide fault diagnosis in systems with continuous dynamics. However, many systems in aerospace and industrial environments are best represented as hybrid systems that consist of discrete behavioral modes, each with its own continuous dynamics. These hybrid dynamics make the on-line fault diagnosis task computationally more complex due to the large number of possible system modes and the existence of autonomous mode transitions. This paper presents a qualitative fault isolation framework for hybrid systems based on structural model decomposition. The fault isolation is performed by analyzing the qualitative information of the residual deviations. However, in hybrid systems this process becomes complex due to possible existence of observation delays, which can cause observed deviations to be inconsistent with the expected deviations for the current mode in the system. The great advantage of structural model decomposition is that (i) it allows to design residuals that respond to only a subset of the faults, and (ii) every time a mode change occurs, only a subset of the residuals will need to be reconfigured, thus reducing the complexity of the reasoning process for isolation purposes. To demonstrate and test the validity of our approach, we use an electric circuit simulation as the case study.

  2. Contextual sensitivity in scientific reproducibility.

    Science.gov (United States)

    Van Bavel, Jay J; Mende-Siedlecki, Peter; Brady, William J; Reinero, Diego A

    2016-06-07

    In recent years, scientists have paid increasing attention to reproducibility. For example, the Reproducibility Project, a large-scale replication attempt of 100 studies published in top psychology journals found that only 39% could be unambiguously reproduced. There is a growing consensus among scientists that the lack of reproducibility in psychology and other fields stems from various methodological factors, including low statistical power, researcher's degrees of freedom, and an emphasis on publishing surprising positive results. However, there is a contentious debate about the extent to which failures to reproduce certain results might also reflect contextual differences (often termed "hidden moderators") between the original research and the replication attempt. Although psychologists have found extensive evidence that contextual factors alter behavior, some have argued that context is unlikely to influence the results of direct replications precisely because these studies use the same methods as those used in the original research. To help resolve this debate, we recoded the 100 original studies from the Reproducibility Project on the extent to which the research topic of each study was contextually sensitive. Results suggested that the contextual sensitivity of the research topic was associated with replication success, even after statistically adjusting for several methodological characteristics (e.g., statistical power, effect size). The association between contextual sensitivity and replication success did not differ across psychological subdisciplines. These results suggest that researchers, replicators, and consumers should be mindful of contextual factors that might influence a psychological process. We offer several guidelines for dealing with contextual sensitivity in reproducibility.

  3. A qualitative descriptive study of spirituality guided by the Neuman systems model.

    Science.gov (United States)

    Lowry, Lois W

    2012-10-01

    The purposes of this qualitative descriptive study were to explore the meaning of spirituality as described by aging adults in various states of health, to describe the relationship between spirituality and health, and to explain client expectations for healthcare providers related to spirituality. All identified meanings and themes were compared to the characteristics of spirituality proposed by Betty Neuman in the Neuman systems model to determine the credibility of the model for assessing and guiding holistic nursing practice. Three themes were formulated: a) Spirituality is an individual, conscious, committed connection to God, requiring a human response; b) positive spirituality contributes to personal wholeness and health; and c) spirituality sustains and comforts in times of stress.

  4. Qualitative Validation of the IMM Model for ISS and STS Programs

    Science.gov (United States)

    Kerstman, E.; Walton, M.; Reyes, D.; Boley, L.; Saile, L.; Young, M.; Arellano, J.; Garcia, Y.; Myers, J. G.

    2016-01-01

    To validate and further improve the Integrated Medical Model (IMM), medical event data were obtained from 32 ISS and 122 STS person-missions. Using the crew characteristics from these observed missions, IMM v4.0 was used to forecast medical events and medical resource utilization. The IMM medical condition incidence values were compared to the actual observed medical event incidence values, and the IMM forecasted medical resource utilization was compared to actual observed medical resource utilization. Qualitative comparisons of these parameters were conducted for both the ISS and STS programs. The results of these analyses will provide validation of IMM v4.0 and reveal areas of the model requiring adjustments to improve the overall accuracy of IMM outputs. This validation effort should result in enhanced credibility of the IMM and improved confidence in the use of IMM as a decision support tool for human space flight.

  5. Use of Game Theory to model patient engagement after surgery: a qualitative analysis.

    Science.gov (United States)

    Castellanos, Stephen A; Buentello, Gerardo; Gutierrez-Meza, Diana; Forgues, Angela; Haubert, Lisa; Artinyan, Avo; Macdonald, Cameron L; Suliburk, James W

    2018-01-01

    Patient engagement is challenging to define and operationalize. Qualitative analysis allows us to explore patient perspectives on this topic and establish themes. A game theoretic signaling model also provides a framework through which to further explore engagement. Over a 6-mo period, thirty-eight interviews were conducted within 6 wk of discharge in patients undergoing thyroid, parathyroid, or colorectal surgery. Interviews were transcribed, anonymized, and analyzed using the NVivo 11 platform. A signaling model was then developed depicting the doctor-patient interaction surrounding the patient's choice to reach out to their physician with postoperative concerns based upon the patient's perspective of the doctor's availability. This was defined as "engagement". We applied the model to the qualitative data to determine possible causations for a patient's engagement or lack thereof. A private hospital's and a safety net hospital's populations were contrasted. The private patient population was more likely to engage than their safety-net counterparts. Using our model in conjunction with patient data, we determined possible etiologies for this engagement to be due to the private patient's perceived probability of dealing with an available doctor and apparent signals from the doctor indicating so. For the safety-net population, decreased access to care caused them to be less willing to engage with a doctor perceived as possibly unavailable. A physician who understands these Game Theory concepts may be able to alter their interactions with their patients, tailoring responses and demeanor to fit the patient's circumstances and possible barriers to engagement. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Analysis of Water Conflicts across Natural and Societal Boundaries: Integration of Quantitative Modeling and Qualitative Reasoning

    Science.gov (United States)

    Gao, Y.; Balaram, P.; Islam, S.

    2009-12-01

    , the knowledge generated from these studies cannot be easily generalized or transferred to other basins. Here, we present an approach to integrate the quantitative and qualitative methods to study water issues and capture the contextual knowledge of water management- by combining the NSSs framework and an area of artificial intelligence called qualitative reasoning. Using the Apalachicola-Chattahoochee-Flint (ACF) River Basin dispute as an example, we demonstrate how quantitative modeling and qualitative reasoning can be integrated to examine the impact of over abstraction of water from the river on the ecosystem and the role of governance in shaping the evolution of the ACF water dispute.

  7. Discrete event simulation tool for analysis of qualitative models of continuous processing systems

    Science.gov (United States)

    Malin, Jane T. (Inventor); Basham, Bryan D. (Inventor); Harris, Richard A. (Inventor)

    1990-01-01

    An artificial intelligence design and qualitative modeling tool is disclosed for creating computer models and simulating continuous activities, functions, and/or behavior using developed discrete event techniques. Conveniently, the tool is organized in four modules: library design module, model construction module, simulation module, and experimentation and analysis. The library design module supports the building of library knowledge including component classes and elements pertinent to a particular domain of continuous activities, functions, and behavior being modeled. The continuous behavior is defined discretely with respect to invocation statements, effect statements, and time delays. The functionality of the components is defined in terms of variable cluster instances, independent processes, and modes, further defined in terms of mode transition processes and mode dependent processes. Model construction utilizes the hierarchy of libraries and connects them with appropriate relations. The simulation executes a specialized initialization routine and executes events in a manner that includes selective inherency of characteristics through a time and event schema until the event queue in the simulator is emptied. The experimentation and analysis module supports analysis through the generation of appropriate log files and graphics developments and includes the ability of log file comparisons.

  8. Being reflexive in qualitative grounded theory: discussion and application of a model of reflexivity.

    Science.gov (United States)

    Engward, Hilary; Davis, Geraldine

    2015-07-01

    A discussion of the meaning of reflexivity in research with the presentation of examples of how a model of reflexivity was used in a grounded theory research project. Reflexivity requires the researcher to make transparent the decisions they make in the research process and is therefore important in developing quality in nursing research. The importance of being reflexive is highlighted in the literature in relation to nursing research, however, practical guidance as to how to go about doing research reflexively is not always clearly articulated. This is a discussion paper. The concept of reflexivity in research is explored using the Alvesson and Skoldberg model of reflexivity and practical examples of how a researcher developed reflexivity in a grounded theory project are presented. Nurse researchers are encouraged to explore and apply the concept of reflexivity in their research practices to develop transparency in the research process and to increase robustness in their research. The Alvesson and Skoldberg model is of value in applying reflexivity in qualitative nursing research, particularly in grounded theory research. Being reflexive requires the researcher to be completely open about decisions that are made in the research process. The Alvesson and Skolberg model of reflexivity is a useful model that can enhance reflexivity in the research process. It can be a useful practical tool to develop reflexivity in grounded theory research. © 2015 John Wiley & Sons Ltd.

  9. A fuzzy-logic-based approach to qualitative safety modelling for marine systems

    International Nuclear Information System (INIS)

    Sii, H.S.; Ruxton, Tom; Wang Jin

    2001-01-01

    Safety assessment based on conventional tools (e.g. probability risk assessment (PRA)) may not be well suited for dealing with systems having a high level of uncertainty, particularly in the feasibility and concept design stages of a maritime or offshore system. By contrast, a safety model using fuzzy logic approach employing fuzzy IF-THEN rules can model the qualitative aspects of human knowledge and reasoning processes without employing precise quantitative analyses. A fuzzy-logic-based approach may be more appropriately used to carry out risk analysis in the initial design stages. This provides a tool for working directly with the linguistic terms commonly used in carrying out safety assessment. This research focuses on the development and representation of linguistic variables to model risk levels subjectively. These variables are then quantified using fuzzy sets. In this paper, the development of a safety model using fuzzy logic approach for modelling various design variables for maritime and offshore safety based decision making in the concept design stage is presented. An example is used to illustrate the proposed approach

  10. Configurational Model for Conductivity of Stabilized Fluorite Structure Oxides

    DEFF Research Database (Denmark)

    Poulsen, Finn Willy

    1981-01-01

    The formalism developed here furnishes means by which ionic configurations, solid solution limits, and conductivity mechanisms in doped fluorite structures can be described. The present model differs markedly from previous models but reproduces qualitatively reality. The analysis reported...

  11. Qualitative and quantitative examination of the performance of regional air quality models representing different modeling approaches

    International Nuclear Information System (INIS)

    Bhumralkar, C.M.; Ludwig, F.L.; Shannon, J.D.; McNaughton, D.

    1985-04-01

    The calculations of three different air quality models were compared with the best available observations. The comparisons were made without calibrating the models to improve agreement with the observations. Model performance was poor for short averaging times (less than 24 hours). Some of the poor performance can be traced to errors in the input meteorological fields, but error exist on all levels. It should be noted that these models were not originally designed for treating short-term episodes. For short-term episodes, much of the variance in the data can arise from small spatial scale features that tend to be averaged out over longer periods. These small spatial scale features cannot be resolved with the coarse grids that are used for the meteorological and emissions inputs. Thus, it is not surprising that the models performed for the longer averaging times. The models compared were RTM-II, ENAMAP-2 and ACID. (17 refs., 5 figs., 4 tabs

  12. Enhancing reproducibility: Failures from Reproducibility Initiatives underline core challenges.

    Science.gov (United States)

    Mullane, Kevin; Williams, Michael

    2017-08-15

    Efforts to address reproducibility concerns in biomedical research include: initiatives to improve journal publication standards and peer review; increased attention to publishing methodological details that enable experiments to be reconstructed; guidelines on standards for study design, implementation, analysis and execution; meta-analyses of multiple studies within a field to synthesize a common conclusion and; the formation of consortia to adopt uniform protocols and internally reproduce data. Another approach to addressing reproducibility are Reproducibility Initiatives (RIs), well-intended, high-profile, systematically peer-vetted initiatives that are intended to replace the traditional process of scientific self-correction. Outcomes from the RIs reported to date have questioned the usefulness of this approach, particularly when the RI outcome differs from other independent self-correction studies that have reproduced the original finding. As a failed RI attempt is a single outcome distinct from the original study, it cannot provide any definitive conclusions necessitating additional studies that the RI approach has neither the ability nor intent of conducting making it a questionable replacement for self-correction. A failed RI attempt also has the potential to damage the reputation of the author of the original finding. Reproduction is frequently confused with replication, an issue that is more than semantic with the former denoting "similarity" and the latter an "exact copy" - an impossible outcome in research because of known and unknown technical, environmental and motivational differences between the original and reproduction studies. To date, the RI framework has negatively impacted efforts to improve reproducibility, confounding attempts to determine whether a research finding is real. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. A method to identify energy efficiency measures for factory systems based on qualitative modeling

    CERN Document Server

    Krones, Manuela

    2017-01-01

    Manuela Krones develops a method that supports factory planners in generating energy-efficient planning solutions. The method provides qualitative description concepts for factory planning tasks and energy efficiency knowledge as well as an algorithm-based linkage between these measures and the respective planning tasks. Its application is guided by a procedure model which allows a general applicability in the manufacturing sector. The results contain energy efficiency measures that are suitable for a specific planning task and reveal the roles of various actors for the measures’ implementation. Contents Driving Concerns for and Barriers against Energy Efficiency Approaches to Increase Energy Efficiency in Factories Socio-Technical Description of Factory Planning Tasks Description of Energy Efficiency Measures Case Studies on Welding Processes and Logistics Systems Target Groups Lecturers and Students of Industrial Engineering, Production Engineering, Environmental Engineering, Mechanical Engineering Practi...

  14. Applying the chronic care model to an employee benefits program: a qualitative inquiry.

    Science.gov (United States)

    Schauer, Gillian L; Wilson, Mark; Barrett, Barbara; Honeycutt, Sally; Hermstad, April K; Kegler, Michelle C

    2013-12-01

    To assess how employee benefits programs may strengthen and/or complement elements of the chronic care model (CCM), a framework used by health systems to improve chronic illness care. A qualitative inquiry consisting of semi-structured interviews with employee benefit administrators and partners from a self-insured, self-administered employee health benefits program was conducted at a large family-owned business in southwest Georgia. Results indicate that the employer adapted and used many health system-related elements of the CCM in the design of their benefit program. Data also suggest that the employee benefits program contributed to self-management skills and to informing and activating patients to interact with the health system. Findings suggest that employee benefits programs can use aspects of the CCM in their own benefit design, and can structure their benefits to contribute to patient-related elements from the CCM.

  15. A method to isolate bacterial communities and characterize ecosystems from food products: Validation and utilization in as a reproducible chicken meat model.

    Science.gov (United States)

    Rouger, Amélie; Remenant, Benoit; Prévost, Hervé; Zagorec, Monique

    2017-04-17

    Influenced by production and storage processes and by seasonal changes the diversity of meat products microbiota can be very variable. Because microbiotas influence meat quality and safety, characterizing and understanding their dynamics during processing and storage is important for proposing innovative and efficient storage conditions. Challenge tests are usually performed using meat from the same batch, inoculated at high levels with one or few strains. Such experiments do not reflect the true microbial situation, and the global ecosystem is not taken into account. Our purpose was to constitute live stocks of chicken meat microbiotas to create standard and reproducible ecosystems. We searched for the best method to collect contaminating bacterial communities from chicken cuts to store as frozen aliquots. We tested several methods to extract DNA of these stored communities for subsequent PCR amplification. We determined the best moment to collect bacteria in sufficient amounts during the product shelf life. Results showed that the rinsing method associated to the use of Mobio DNA extraction kit was the most reliable method to collect bacteria and obtain DNA for subsequent PCR amplification. Then, 23 different chicken meat microbiotas were collected using this procedure. Microbiota aliquots were stored at -80°C without important loss of viability. Their characterization by cultural methods confirmed the large variability (richness and abundance) of bacterial communities present on chicken cuts. Four of these bacterial communities were used to estimate their ability to regrow on meat matrices. Challenge tests performed on sterile matrices showed that these microbiotas were successfully inoculated and could overgrow the natural microbiota of chicken meat. They can therefore be used for performing reproducible challenge tests mimicking a true meat ecosystem and enabling the possibility to test the influence of various processing or storage conditions on complex meat

  16. Fault Tree Analysis with Temporal Gates and Model Checking Technique for Qualitative System Safety Analysis

    International Nuclear Information System (INIS)

    Koh, Kwang Yong; Seong, Poong Hyun

    2010-01-01

    Fault tree analysis (FTA) has suffered from several drawbacks such that it uses only static gates and hence can not capture dynamic behaviors of the complex system precisely, and it is in lack of rigorous semantics, and reasoning process which is to check whether basic events really cause top events is done manually and hence very labor-intensive and time-consuming for the complex systems while it has been one of the most widely used safety analysis technique in nuclear industry. Although several attempts have been made to overcome this problem, they can not still do absolute or actual time modeling because they adapt relative time concept and can capture only sequential behaviors of the system. In this work, to resolve the problems, FTA and model checking are integrated to provide formal, automated and qualitative assistance to informal and/or quantitative safety analysis. Our approach proposes to build a formal model of the system together with fault trees. We introduce several temporal gates based on timed computational tree logic (TCTL) to capture absolute time behaviors of the system and to give concrete semantics to fault tree gates to reduce errors during the analysis, and use model checking technique to automate the reasoning process of FTA

  17. An Early Model for Value and Sustainability in Health Information Exchanges: Qualitative Study.

    Science.gov (United States)

    Feldman, Sue S

    2018-04-30

    The primary value relative to health information exchange has been seen in terms of cost savings relative to laboratory and radiology testing, emergency department expenditures, and admissions. However, models are needed to statistically quantify value and sustainability and better understand the dependent and mediating factors that contribute to value and sustainability. The purpose of this study was to provide a basis for early model development for health information exchange value and sustainability. A qualitative study was conducted with 21 interviews of eHealth Exchange participants across 10 organizations. Using a grounded theory approach and 3.0 as a relative frequency threshold, 5 main categories and 16 subcategories emerged. This study identifies 3 core current perceived value factors and 5 potential perceived value factors-how interviewees predict health information exchanges may evolve as there are more participants. These value factors were used as the foundation for early model development for sustainability of health information exchange. Using the value factors from the interviews, the study provides the basis for early model development for health information exchange value and sustainability. This basis includes factors from the research: fostering consumer engagement; establishing a provider directory; quantifying use, cost, and clinical outcomes; ensuring data integrity through patient matching; and increasing awareness, usefulness, interoperability, and sustainability of eHealth Exchange. ©Sue S Feldman. Originally published in JMIR Medical Informatics (http://medinform.jmir.org), 30.04.2018.

  18. A qualitative assessment of a community antiretroviral therapy group model in Tete, Mozambique.

    Directory of Open Access Journals (Sweden)

    Freya Rasschaert

    Full Text Available BACKGROUND: To improve retention on ART, Médecins Sans Frontières, the Ministry of Health and patients piloted a community-based antiretroviral distribution and adherence monitoring model through Community ART Groups (CAG in Tete, Mozambique. By December 2012, almost 6000 patients on ART had formed groups of whom 95.7% were retained in care. We conducted a qualitative study to evaluate the relevance, dynamic and impact of the CAG model on patients, their communities and the healthcare system. METHODS: Between October 2011 and May 2012, we conducted 16 focus group discussions and 24 in-depth interviews with the major stakeholders involved in the CAG model. Audio-recorded data were transcribed verbatim and analysed using a grounded theory approach. RESULTS: Six key themes emerged from the data: 1 Barriers to access HIV care, 2 CAG functioning and actors involved, 3 Benefits for CAG members, 4 Impacts of CAG beyond the group members, 5 Setbacks, and 6 Acceptance and future expectations of the CAG model. The model provides cost and time savings, certainty of ART access and mutual peer support resulting in better adherence to treatment. Through the active role of patients, HIV information could be conveyed to the broader community, leading to an increased uptake of services and positive transformation of the identity of people living with HIV. Potential pitfalls included limited access to CAG for those most vulnerable to defaulting, some inequity to patients in individual ART care and a high dependency on counsellors. CONCLUSION: The CAG model resulted in active patient involvement and empowerment, and the creation of a supportive environment improving the ART retention. It also sparked a reorientation of healthcare services towards the community and strengthened community actions. Successful implementation and scalability requires (a the acceptance of patients as partners in health, (b adequate resources, and (c a well-functioning monitoring and

  19. Comparing Reasons for Quitting Substance Abuse with the Constructs of Behavioral Models: A Qualitative Study

    Directory of Open Access Journals (Sweden)

    Hamid Tavakoli Ghouchani

    2015-03-01

    Full Text Available Background and Objectives: The world population has reached over seven billion people. Of these, 230 million individuals abuse substances. Therefore, substance abuse prevention and treatment programs have received increasing attention during the past two decades. Understanding people’s motivations for quitting drug abuse is essential to the success of treatment. This study hence sought to identify major motivations for quitting and to compare them with the constructs of health education models. Materials and Methods: In the present study, qualitative content analysis was used to determine the main motivations for quitting substance abuse. Overall, 22 patients, physicians, and psychotherapists were selected from several addiction treatment clinics in Bojnord (Iran during 2014. Purposeful sampling method was applied and continued until data saturation was achieved. Data were collected through semi-structured, face-to-face interviews and field notes. All interviews were recorded and transcribed. Results: Content analysis revealed 33 sub-categories and nine categories including economic problems, drug-related concerns, individual problems, family and social problems, family expectations, attention to social status, beliefs about drug addiction, and valuing the quitting behavior. Accordingly, four themes, i.e. perceived threat, perceived barriers, attitude toward the behavior, and subjective norms, were extracted. Conclusion: Reasons for quitting substance abuse match the constructs of different behavioral models (e.g. the health belief model and the theory of planned behavior.

  20. Religious views of the 'medical' rehabilitation model: a pilot qualitative study.

    Science.gov (United States)

    Yamey, Gavin; Greenwood, Richard

    2004-04-22

    To explore the religious beliefs that patients may bring to the rehabilitation process, and the hypothesis that these beliefs may diverge from the medical model of rehabilitation. Qualitative semi-structured interviews with representatives of six major religions--Islam, Buddhism, Christianity, Judaism, Sikhism, and Hinduism. Representatives were either health care professionals or religious leaders, all with an interest in how their religion approached health issues. There were three recurrent themes in the interviews: religious explanations for injury and illness; beliefs about recovery; religious duties of care towards family members. The Buddhist, Sikh, and Hindu interviewees described beliefs about karma--unfortunate events happening due to a person's former deeds. Fatalistic ideas, involving God having control over an individual's recovery, were expressed by the Muslim, Jewish, and Christian interviewees. All interviewees expressed the fundamental importance of a family's religious duty of care towards ill or injured relatives, and all expressed some views that were compatible with the medical model of rehabilitation. Religious beliefs may both diverge from and resonate with the medical rehabilitation model. Understanding these beliefs may be valuable in facilitating the rehabilitation of diverse religious groups.

  1. European cold winter 2009-2010: How unusual in the instrumental record and how reproducible in the ARPEGE-Climat model?

    Science.gov (United States)

    Ouzeau, G.; Cattiaux, J.; Douville, H.; Ribes, A.; Saint-Martin, D.

    2011-06-01

    Boreal winter 2009-2010 made headlines for cold anomalies in many countries of the northern mid-latitudes. Northern Europe was severely hit by this harsh winter in line with a record persistence of the negative phase of the North Atlantic Oscillation (NAO). In the present study, we first provide a wider perspective on how unusual this winter was by using the recent 20th Century Reanalysis. A weather regime analysis shows that the frequency of the negative NAO was unprecedented since winter 1939-1940, which is then used as a dynamical analog of winter 2009-2010 to demonstrate that the latter might have been much colder without the background global warming observed during the twentieth century. We then use an original nudging technique in ensembles of global atmospheric simulations driven by observed sea surface temperature (SST) and radiative forcings to highlight the relevance of the stratosphere for understanding if not predicting such anomalous winter seasons. Our results demonstrate that an improved representation of the lower stratosphere is necessary to reproduce not only the seasonal mean negative NAO signal, but also its intraseasonal distribution and the corresponding increased probability of cold waves over northern Europe.

  2. From qualitative data to quantitative models: analysis of the phage shock protein stress response in Escherichia coli

    Directory of Open Access Journals (Sweden)

    Jovanovic Goran

    2011-05-01

    Full Text Available Abstract Background Bacteria have evolved a rich set of mechanisms for sensing and adapting to adverse conditions in their environment. These are crucial for their survival, which requires them to react to extracellular stresses such as heat shock, ethanol treatment or phage infection. Here we focus on studying the phage shock protein (Psp stress response in Escherichia coli induced by a phage infection or other damage to the bacterial membrane. This system has not yet been theoretically modelled or analysed in silico. Results We develop a model of the Psp response system, and illustrate how such models can be constructed and analyzed in light of available sparse and qualitative information in order to generate novel biological hypotheses about their dynamical behaviour. We analyze this model using tools from Petri-net theory and study its dynamical range that is consistent with currently available knowledge by conditioning model parameters on the available data in an approximate Bayesian computation (ABC framework. Within this ABC approach we analyze stochastic and deterministic dynamics. This analysis allows us to identify different types of behaviour and these mechanistic insights can in turn be used to design new, more detailed and time-resolved experiments. Conclusions We have developed the first mechanistic model of the Psp response in E. coli. This model allows us to predict the possible qualitative stochastic and deterministic dynamic behaviours of key molecular players in the stress response. Our inferential approach can be applied to stress response and signalling systems more generally: in the ABC framework we can condition mathematical models on qualitative data in order to delimit e.g. parameter ranges or the qualitative system dynamics in light of available end-point or qualitative information.

  3. Reproducibility of a reaming test

    DEFF Research Database (Denmark)

    Pilny, Lukas; Müller, Pavel; De Chiffre, Leonardo

    2012-01-01

    The reproducibility of a reaming test was analysed to document its applicability as a performance test for cutting fluids. Reaming tests were carried out on a drilling machine using HSS reamers. Workpiece material was an austenitic stainless steel, machined using 4.75 m∙min-1 cutting speed and 0....

  4. Reproducibility of a reaming test

    DEFF Research Database (Denmark)

    Pilny, Lukas; Müller, Pavel; De Chiffre, Leonardo

    2014-01-01

    The reproducibility of a reaming test was analysed to document its applicability as a performance test for cutting fluids. Reaming tests were carried out on a drilling machine using HSS reamers. Workpiece material was an austenitic stainless steel, machined using 4.75 m•min−1 cutting speed and 0....

  5. Reproducible Bioinformatics Research for Biologists

    Science.gov (United States)

    This book chapter describes the current Big Data problem in Bioinformatics and the resulting issues with performing reproducible computational research. The core of the chapter provides guidelines and summaries of current tools/techniques that a noncomputational researcher would need to learn to pe...

  6. Bad Behavior: Improving Reproducibility in Behavior Testing.

    Science.gov (United States)

    Andrews, Anne M; Cheng, Xinyi; Altieri, Stefanie C; Yang, Hongyan

    2018-01-24

    Systems neuroscience research is increasingly possible through the use of integrated molecular and circuit-level analyses. These studies depend on the use of animal models and, in many cases, molecular and circuit-level analyses. Associated with genetic, pharmacologic, epigenetic, and other types of environmental manipulations. We illustrate typical pitfalls resulting from poor validation of behavior tests. We describe experimental designs and enumerate controls needed to improve reproducibility in investigating and reporting of behavioral phenotypes.

  7. Preliminary clinical nursing leadership competency model: a qualitative study from Thailand.

    Science.gov (United States)

    Supamanee, Treeyaphan; Krairiksh, Marisa; Singhakhumfu, Laddawan; Turale, Sue

    2011-12-01

    This qualitative study explored the clinical nursing leadership competency perspectives of Thai nurses working in a university hospital. To collect data, in-depth interviews were undertaken with 23 nurse administrators, and focus groups were used with 31 registered nurses. Data were analyzed using content analysis, and theory development was guided by the Iceberg model. Nurses' clinical leadership competencies emerged, comprising hidden characteristics and surface characteristics. The hidden characteristics composed three elements: motive (respect from the nursing and healthcare team and being secure in life), self-concept (representing positive attitudes and values), and traits (personal qualities necessary for leadership). The surface characteristics comprised specific knowledge of nurse leaders about clinical leadership, management and nursing informatics, and clinical skills, such as coordination, effective communication, problem solving, and clinical decision-making. The study findings help nursing to gain greater knowledge of the essence of clinical nursing leadership competencies, a matter critical for theory development in leadership. This study's results later led to the instigation of a training program for registered nurse leaders at the study site, and the formation of a preliminary clinical nursing leadership competency model. © 2011 Blackwell Publishing Asia Pty Ltd.

  8. The Reflective Model of Intercultural Competency: A Multidimensional, Qualitative Approach to Study Abroad Assessment

    Science.gov (United States)

    Williams, Tracy Rundstrom

    2009-01-01

    Judging from the recent surge in research on outcomes assessment, many study abroad offices rely on quantitative surveys and measures to collect student outcomes data. This paper presents a multidimensional, qualitative approach to data collection. This approach makes qualitative data easy to collect and encourages students to reflect and…

  9. The Maudsley Model of Family-Based Treatment for Anorexia Nervosa: A Qualitative Evaluation of Parent-to-Parent Consultation

    Science.gov (United States)

    Rhodes, Paul; Brown, Jac; Madden, Sloane

    2009-01-01

    This article describes the qualitative analysis of a randomized control trial that explores the use of parent-to-parent consultations as an augmentation to the Maudsley model of family-based treatment for anorexia. Twenty families were randomized into two groups, 10 receiving standard treatment and 10 receiving an additional parent-to-parent…

  10. Qualitative Contrast between Knowledge-Limited Mixed-State and Variable-Resources Models of Visual Change Detection

    Science.gov (United States)

    Nosofsky, Robert M.; Donkin, Chris

    2016-01-01

    We report an experiment designed to provide a qualitative contrast between knowledge-limited versions of mixed-state and variable-resources (VR) models of visual change detection. The key data pattern is that observers often respond "same" on big-change trials, while simultaneously being able to discriminate between same and small-change…

  11. Blackboard architecture and qualitative model in a computer aided assistant designed to define computers for HEP computing

    International Nuclear Information System (INIS)

    Nodarse, F.F.; Ivanov, V.G.

    1991-01-01

    Using BLACKBOARD architecture and qualitative model, an expert systm was developed to assist the use in defining the computers method for High Energy Physics computing. The COMEX system requires an IBM AT personal computer or compatible with than 640 Kb RAM and hard disk. 5 refs.; 9 figs

  12. Evaluation of Land Surface Models in Reproducing Satellite-Derived LAI over the High-Latitude Northern Hemisphere. Part I: Uncoupled DGVMs

    Directory of Open Access Journals (Sweden)

    Ning Zeng

    2013-10-01

    Full Text Available Leaf Area Index (LAI represents the total surface area of leaves above a unit area of ground and is a key variable in any vegetation model, as well as in climate models. New high resolution LAI satellite data is now available covering a period of several decades. This provides a unique opportunity to validate LAI estimates from multiple vegetation models. The objective of this paper is to compare new, satellite-derived LAI measurements with modeled output for the Northern Hemisphere. We compare monthly LAI output from eight land surface models from the TRENDY compendium with satellite data from an Artificial Neural Network (ANN from the latest version (third generation of GIMMS AVHRR NDVI data over the period 1986–2005. Our results show that all the models overestimate the mean LAI, particularly over the boreal forest. We also find that seven out of the eight models overestimate the length of the active vegetation-growing season, mostly due to a late dormancy as a result of a late summer phenology. Finally, we find that the models report a much larger positive trend in LAI over this period than the satellite observations suggest, which translates into a higher trend in the growing season length. These results highlight the need to incorporate a larger number of more accurate plant functional types in all models and, in particular, to improve the phenology of deciduous trees.

  13. Designing a Qualitative Model of Doping Phenomenon Effect on Sport Marketing in Iran

    Directory of Open Access Journals (Sweden)

    Jasem Manouchehri

    2016-10-01

    Full Text Available There a number of factors effecting consumers' purchase behavior. It is believed that celebrities can effect selling positively by transferring their popular image to the endorsed product. But, it is heard lots about excommunicate behaviors in the sport world today. Disclosure of the recent doping affairs relating to Lance Armstrong's seven wins in Tour De France is just one among many spectacular and also negative cases. The main aim of the present paper was to explore the effect of doping phenomenon on sport marketing. Depth interviews data were analyzed in three phases: open coding, axial coding, and selective coding. 297 open codes were achieved by 18 interviews. Grouping axial codes in each case and comparing, all gained codes can be divided in five groups: brand image (athlete and endorsed product brands images, moral reasoning (moral coupling, moral decoupling, and moral rationalization, consumer behavioral consequences (word of mouth, purchasing intention, and brand loyalty, attitude change (attitudes change toward athlete and brand, and moral emotions (moral evaluation, contempt, anger, disgust, and sympathy. The proposed qualitative model for the effect of doping phenomenon on sport marketing in Iran illustrated that moral emotions and product brand image affected by the doped athlete brand image and it resulted in attitudes change toward endorser athlete and endorsed brand and negative consumer behavioral consequences, however, moral reasoning strategies emerged by cognitive dissonance might protect consumers behavior from negative effects.

  14. Business Models, Vaccination Services, and Public Health Relationships of Retail Clinics: A Qualitative Study.

    Science.gov (United States)

    Arthur, Bayo C; Fisher, Allison Kennedy; Shoemaker, Sarah J; Pozniak, Alyssa; Stokley, Shannon

    2015-01-01

    Despite the rapid growth of retail clinics (RCs), literature is limited in terms of how these facilities offer preventive services, particularly vaccination services. The purpose of this study was to obtain an in-depth understanding of the RC business model pertaining to vaccine offerings, profitability, and decision making. From March to June 2009, we conducted 15 interviews with key individuals from three types of organizations: 12 representatives of RC corporations, 2 representatives of retail hosts (i.e., stores in which the RCs are located), and 1 representative of an industry association. We analyzed interview transcripts qualitatively. Our results indicate that consumer demand and profitability were the main drivers in offering vaccinations. RCs in this sample primarily offered vaccinations to adults and adolescents, and they were not well integrated with local public health and immunization registries. Our findings demonstrate the potential for stronger linkages with public health in these settings. The findings also may help inform future research to increase patient access to vaccination services at RCs.

  15. Evaluation of multichannel reproduced sound

    DEFF Research Database (Denmark)

    Choisel, Sylvain; Wickelmaier, Florian Maria

    2007-01-01

    from the quantified attributes predict overall preference well. The findings allow for some generalizations within musical program genres regarding the perception of and preference for certain spatial reproduction modes, but for limited generalizations across selections from different musical genres.......A study was conducted with the goal of quantifying auditory attributes which underlie listener preference for multichannel reproduced sound. Short musical excerpts were presented in mono, stereo and several multichannel formats to a panel of forty selected listeners. Scaling of auditory attributes...

  16. Qualitative evaluation of adherence therapy in Parkinson’s disease: a multidirectional model

    Directory of Open Access Journals (Sweden)

    Daley DJ

    2015-07-01

    Full Text Available David James Daley,1,2 Katherine Helen O’Leary Deane,3 Richard John Gray,4 Rebekah Hill,3 Phyo Kyaw Myint5 1Norwich Medical School, Faculty of Medicine and Health Sciences, University of East Anglia, Norwich Research Park, 2Norfolk and Norwich University Hospital NHS Foundation Trust, 3School of Health Sciences, University of East Anglia, Norwich Research Park, Norwich, UK; 4Hamad Medical Corporation, Doha, Qatar; 5Epidemiology Group, School of Medicine and Dentistry, Institute of Applied Health Sciences, College of Life Sciences and Medicine, University of Aberdeen, Aberdeen, UK Background: Medication can control the symptoms of Parkinson’s disease (PD. Despite this, non-adherence with medication is prevalent in PD. Treatments for improving adherence with medication have been investigated in many chronic conditions, including PD. However, few researchers have evaluated their interventions qualitatively. We investigated the acceptability and potential mechanism of action of adherence therapy (AT in PD patients and their spouse/carers who received the intervention as part of a randomized controlled trial. Methods: Sixteen participants (ten patients and six spouses/carers who had recently completed the trial were purposely selected in order to cover a range of ages and disease severity. Semi-structured interviews were conducted in the participants’ homes. Data were transcribed and analyzed using a thematic approach. A second researcher, naïve to PD and AT, analyzed the data independently to limit bias. Results: The trial showed that AT significantly improved both medication adherence and quality of life in people with PD. Specifically, patients who received AT reported improvements in mobility, activities of daily living, emotional wellbeing, cognition, communication, and body discomfort. General beliefs about medication also significantly improved in those who received AT compared with controls. In the current qualitative evaluation, a

  17. Qualitatively Modeling solute fate and transport across scales in an agricultural catchment with diverse lithology

    Science.gov (United States)

    Wayman, C. R.; Russo, T. A.; Li, L.; Forsythe, B.; Hoagland, B.

    2017-12-01

    As part of the Susquehanna Shale Hills Critical Zone Observatory (SSHCZO) project, we have collected geochemical and hydrological data from several subcatchments and four monitoring sites on the main stem of Shaver's Creek, in Huntingon county, Pennsylvania. One subcatchment (0.43 km2) is under agricultural land use, and the monitoring locations on the larger Shaver's Creek (up to 163 km2) drain watersheds with 0 to 25% agricultural area. These two scales of investigation, coupled with advances made across the SSHCZO on multiple lithologies allow us to extrapolate from the subcatchment to the larger watershed. We use geochemical surface and groundwater data to estimate the solute and water transport regimes within the catchment, and to show how lithology and land use are major controls on ground and surface water quality. One area of investigation includes the transport of nutrients between interflow and regional groundwater, and how that connectivity may be reflected in local surface waters. Water and nutrient (Nitrogen) isotopes, will be used to better understand the relative contributions of local and regional groundwater and interflow fluxes into nearby streams. Following initial qualitative modeling, multiple hydrologic and nutrient transport models (e.g. SWAT and CYCLES/PIHM) will be evaluated from the subcatchment to large watershed scales. We will evaluate the ability to simulate the contributions of regional groundwater versus local groundwater, and also impacts of agricultural land management on surface water quality. Improving estimations of groundwater contributions to stream discharge will provide insight into how much agricultural development can impact stream quality and nutrient loading.

  18. How well do environmental archives of atmospheric mercury deposition in the Arctic reproduce rates and trends depicted by atmospheric models and measurements?

    Science.gov (United States)

    Goodsite, M E; Outridge, P M; Christensen, J H; Dastoor, A; Muir, D; Travnikov, O; Wilson, S

    2013-05-01

    This review compares the reconstruction of atmospheric Hg deposition rates and historical trends over recent decades in the Arctic, inferred from Hg profiles in natural archives such as lake and marine sediments, peat bogs and glacial firn (permanent snowpack), against those predicted by three state-of-the-art atmospheric models based on global Hg emission inventories from 1990 onwards. Model veracity was first tested against atmospheric Hg measurements. Most of the natural archive and atmospheric data came from the Canadian-Greenland sectors of the Arctic, whereas spatial coverage was poor in other regions. In general, for the Canadian-Greenland Arctic, models provided good agreement with atmospheric gaseous elemental Hg (GEM) concentrations and trends measured instrumentally. However, there are few instrumented deposition data with which to test the model estimates of Hg deposition, and these data suggest models over-estimated deposition fluxes under Arctic conditions. Reconstructed GEM data from glacial firn on Greenland Summit showed the best agreement with the known decline in global Hg emissions after about 1980, and were corroborated by archived aerosol filter data from Resolute, Nunavut. The relatively stable or slowly declining firn and model GEM trends after 1990 were also corroborated by real-time instrument measurements at Alert, Nunavut, after 1995. However, Hg fluxes and trends in northern Canadian lake sediments and a southern Greenland peat bog did not exhibit good agreement with model predictions of atmospheric deposition since 1990, the Greenland firn GEM record, direct GEM measurements, or trends in global emissions since 1980. Various explanations are proposed to account for these discrepancies between atmosphere and archives, including problems with the accuracy of archive chronologies, climate-driven changes in Hg transfer rates from air to catchments, waters and subsequently into sediments, and post-depositional diagenesis in peat bogs

  19. Chow-Liu trees are sufficient predictive models for reproducing key features of functional networks of periictal EEG time-series.

    Science.gov (United States)

    Steimer, Andreas; Zubler, Frédéric; Schindler, Kaspar

    2015-09-01

    Seizure freedom in patients suffering from pharmacoresistant epilepsies is still not achieved in 20-30% of all cases. Hence, current therapies need to be improved, based on a more complete understanding of ictogenesis. In this respect, the analysis of functional networks derived from intracranial electroencephalographic (iEEG) data has recently become a standard tool. Functional networks however are purely descriptive models and thus are conceptually unable to predict fundamental features of iEEG time-series, e.g., in the context of therapeutical brain stimulation. In this paper we present some first steps towards overcoming the limitations of functional network analysis, by showing that its results are implied by a simple predictive model of time-sliced iEEG time-series. More specifically, we learn distinct graphical models (so called Chow-Liu (CL) trees) as models for the spatial dependencies between iEEG signals. Bayesian inference is then applied to the CL trees, allowing for an analytic derivation/prediction of functional networks, based on thresholding of the absolute value Pearson correlation coefficient (CC) matrix. Using various measures, the thus obtained networks are then compared to those which were derived in the classical way from the empirical CC-matrix. In the high threshold limit we find (a) an excellent agreement between the two networks and (b) key features of periictal networks as they have previously been reported in the literature. Apart from functional networks, both matrices are also compared element-wise, showing that the CL approach leads to a sparse representation, by setting small correlations to values close to zero while preserving the larger ones. Overall, this paper shows the validity of CL-trees as simple, spatially predictive models for periictal iEEG data. Moreover, we suggest straightforward generalizations of the CL-approach for modeling also the temporal features of iEEG signals. Copyright © 2015 Elsevier Inc. All rights

  20. Theoretical Modeling and Computer Simulations for the Origins and Evolution of Reproducing Molecular Systems and Complex Systems with Many Interactive Parts

    Science.gov (United States)

    Liang, Shoudan

    2000-01-01

    Our research effort has produced nine publications in peer-reviewed journals listed at the end of this report. The work reported here are in the following areas: (1) genetic network modeling; (2) autocatalytic model of pre-biotic evolution; (3) theoretical and computational studies of strongly correlated electron systems; (4) reducing thermal oscillations in atomic force microscope; (5) transcription termination mechanism in prokaryotic cells; and (6) the low glutamine usage in thennophiles obtained by studying completely sequenced genomes. We discuss the main accomplishments of these publications.

  1. Experiences of role model instructors and nursing students about facilitator factors of role-modeling process: A qualitative research

    OpenAIRE

    Nouri, Jamileh Mokhtari; Ebadi, Abbas; Alhani, Fatemeh; Rejeh, Nahid

    2014-01-01

    Background: One of the key strategies in students’ learning is the influence of models on them. Understanding the factors affecting the implementation of role-modeling process in education will help to make greater use of this training strategy. This study aimed to understand the experiences of role model instructors and nursing students about the facilitator factors in the role-modeling process. Material and Methods: This qualitative study was carried out by using thematic analysis method an...

  2. Adjustments in the Almod 3W2 code models for reproducing the net load trip test in Angra I nuclear power plant

    International Nuclear Information System (INIS)

    Camargo, C.T.M.; Madeira, A.A.; Pontedeiro, A.C.; Dominguez, L.

    1986-09-01

    The recorded traces got from the net load trip test in Angra I NPP yelded the oportunity to make fine adjustments in the ALMOD 3W2 code models. The changes are described and the results are compared against plant real data. (Author) [pt

  3. An International Ki67 Reproducibility Study

    Science.gov (United States)

    2013-01-01

    Background In breast cancer, immunohistochemical assessment of proliferation using the marker Ki67 has potential use in both research and clinical management. However, lack of consistency across laboratories has limited Ki67’s value. A working group was assembled to devise a strategy to harmonize Ki67 analysis and increase scoring concordance. Toward that goal, we conducted a Ki67 reproducibility study. Methods Eight laboratories received 100 breast cancer cases arranged into 1-mm core tissue microarrays—one set stained by the participating laboratory and one set stained by the central laboratory, both using antibody MIB-1. Each laboratory scored Ki67 as percentage of positively stained invasive tumor cells using its own method. Six laboratories repeated scoring of 50 locally stained cases on 3 different days. Sources of variation were analyzed using random effects models with log2-transformed measurements. Reproducibility was quantified by intraclass correlation coefficient (ICC), and the approximate two-sided 95% confidence intervals (CIs) for the true intraclass correlation coefficients in these experiments were provided. Results Intralaboratory reproducibility was high (ICC = 0.94; 95% CI = 0.93 to 0.97). Interlaboratory reproducibility was only moderate (central staining: ICC = 0.71, 95% CI = 0.47 to 0.78; local staining: ICC = 0.59, 95% CI = 0.37 to 0.68). Geometric mean of Ki67 values for each laboratory across the 100 cases ranged 7.1% to 23.9% with central staining and 6.1% to 30.1% with local staining. Factors contributing to interlaboratory discordance included tumor region selection, counting method, and subjective assessment of staining positivity. Formal counting methods gave more consistent results than visual estimation. Conclusions Substantial variability in Ki67 scoring was observed among some of the world’s most experienced laboratories. Ki67 values and cutoffs for clinical decision-making cannot be transferred between laboratories without

  4. Systematic Methodology for Reproducible Optimizing Batch Operation

    DEFF Research Database (Denmark)

    Bonné, Dennis; Jørgensen, Sten Bay

    2006-01-01

    contribution furthermore presents how the asymptotic convergence of Iterative Learning Control is combined with the closed-loop performance of Model Predictive Control to form a robust and asymptotically stable optimal controller for ensuring reliable and reproducible operation of batch processes....... This controller may also be used for Optimizing control. The modeling and control performance is demonstrated on a fed-batch protein cultivation example. The presented methodologies lend themselves directly for application as Process Analytical Technologies (PAT).......This contribution presents a systematic methodology for rapid acquirement of discrete-time state space model representations of batch processes based on their historical operation data. These state space models are parsimoniously parameterized as a set of local, interdependent models. The present...

  5. Disease management projects and the Chronic Care Model in action: baseline qualitative research

    Directory of Open Access Journals (Sweden)

    Walters Bethany

    2012-05-01

    Full Text Available Abstract Background Disease management programs, especially those based on the Chronic Care Model (CCM, are increasingly common in the Netherlands. While disease management programs have been well-researched quantitatively and economically, less qualitative research has been done. The overall aim of the study is to explore how disease management programs are implemented within primary care settings in the Netherlands; this paper focuses on the early development and implementation stages of five disease management programs in the primary care setting, based on interviews with project leadership teams. Methods Eleven semi-structured interviews were conducted at the five selected sites with sixteen professionals interviewed; all project directors and managers were interviewed. The interviews focused on each project’s chosen chronic illness (diabetes, eating disorders, COPD, multi-morbidity, CVRM and project plan, barriers to development and implementation, the project leaders’ action and reactions, as well as their roles and responsibilities, and disease management strategies. Analysis was inductive and interpretive, based on the content of the interviews. After analysis, the results of this research on disease management programs and the Chronic Care Model are viewed from a traveling technology framework. Results This analysis uncovered four themes that can be mapped to disease management and the Chronic Care Model: (1 changing the health care system, (2 patient-centered care, (3 technological systems and barriers, and (4 integrating projects into the larger system. Project leaders discussed the paths, both direct and indirect, for transforming the health care system to one that addresses chronic illness. Patient-centered care was highlighted as needed and a paradigm shift for many. Challenges with technological systems were pervasive. Project leaders managed the expenses of a traveling technology, including the social, financial, and

  6. Disease management projects and the Chronic Care Model in action: baseline qualitative research.

    Science.gov (United States)

    Walters, Bethany Hipple; Adams, Samantha A; Nieboer, Anna P; Bal, Roland

    2012-05-11

    Disease management programs, especially those based on the Chronic Care Model (CCM), are increasingly common in The Netherlands. While disease management programs have been well-researched quantitatively and economically, less qualitative research has been done. The overall aim of the study is to explore how disease management programs are implemented within primary care settings in The Netherlands; this paper focuses on the early development and implementation stages of five disease management programs in the primary care setting, based on interviews with project leadership teams. Eleven semi-structured interviews were conducted at the five selected sites with sixteen professionals interviewed; all project directors and managers were interviewed. The interviews focused on each project's chosen chronic illness (diabetes, eating disorders, COPD, multi-morbidity, CVRM) and project plan, barriers to development and implementation, the project leaders' action and reactions, as well as their roles and responsibilities, and disease management strategies. Analysis was inductive and interpretive, based on the content of the interviews. After analysis, the results of this research on disease management programs and the Chronic Care Model are viewed from a traveling technology framework. This analysis uncovered four themes that can be mapped to disease management and the Chronic Care Model: (1) changing the health care system, (2) patient-centered care, (3) technological systems and barriers, and (4) integrating projects into the larger system. Project leaders discussed the paths, both direct and indirect, for transforming the health care system to one that addresses chronic illness. Patient-centered care was highlighted as needed and a paradigm shift for many. Challenges with technological systems were pervasive. Project leaders managed the expenses of a traveling technology, including the social, financial, and administration involved. At the sites, project leaders served

  7. Navigating the complexities of qualitative comparative analysis: case numbers, necessity relations, and model ambiguities.

    Science.gov (United States)

    Thiem, Alrik

    2014-12-01

    In recent years, the method of Qualitative Comparative Analysis (QCA) has been enjoying increasing levels of popularity in evaluation and directly neighboring fields. Its holistic approach to causal data analysis resonates with researchers whose theories posit complex conjunctions of conditions and events. However, due to QCA's relative immaturity, some of its technicalities and objectives have not yet been well understood. In this article, I seek to raise awareness of six pitfalls of employing QCA with regard to the following three central aspects: case numbers, necessity relations, and model ambiguities. Most importantly, I argue that case numbers are irrelevant to the methodological choice of QCA or any of its variants, that necessity is not as simple a concept as it has been suggested by many methodologists, and that doubt must be cast on the determinacy of virtually all results presented in past QCA research. By means of empirical examples from published articles, I explain the background of these pitfalls and introduce appropriate procedures, partly with reference to current software, that help avoid them. QCA carries great potential for scholars in evaluation and directly neighboring areas interested in the analysis of complex dependencies in configurational data. If users beware of the pitfalls introduced in this article, and if they avoid mechanistic adherence to doubtful "standards of good practice" at this stage of development, then research with QCA will gain in quality, as a result of which a more solid foundation for cumulative knowledge generation and well-informed policy decisions will also be created. © The Author(s) 2014.

  8. The explanatory models of depression and anxiety in primary care: a qualitative study from India

    Directory of Open Access Journals (Sweden)

    Andrew Gracy

    2012-09-01

    Full Text Available Abstract Background The biggest barrier to treatment of common mental disorders in primary care settings is low recognition among health care providers. This study attempts to explore the explanatory models of common mental disorders (CMD with the goal of identifying how they could help in improving the recognition, leading to effective treatment in primary care. Results The paper describes findings of a cross sectional qualitative study nested within a large randomized controlled trial (the Manas trial. Semi structured interviews were conducted with 117 primary health care attendees (30 males and 87 females suffering from CMD. Main findings of the study are that somatic phenomena were by far the most frequent presenting problems; however, psychological phenomena were relatively easily elicited on probing. Somatic phenomena were located within a biopsychosocial framework, and a substantial proportion of informants used the psychological construct of ‘tension’ or ‘worry’ to label their illness, but did not consider themselves as suffering from a ‘mental disorder’. Very few gender differences were observed in the descriptions of symptoms but at the same time the pattern of adverse life events and social difficulties varied across gender. Conclusion Our study demonstrates how people present their illness through somatic complaints but clearly link their illness to their psychosocial world. However they do not associate their illness to a ‘mental disorder’ and this is an important phenomenon that needs to be recognized in management of CMD in primary settings. Our study also elicits important gender differences in the experience of CMD.

  9. Simulation of the hydrodynamic conditions of the eye to better reproduce the drug release from hydrogel contact lenses: experiments and modeling.

    Science.gov (United States)

    Pimenta, A F R; Valente, A; Pereira, J M C; Pereira, J C F; Filipe, H P; Mata, J L G; Colaço, R; Saramago, B; Serro, A P

    2016-12-01

    Currently, most in vitro drug release studies for ophthalmic applications are carried out in static sink conditions. Although this procedure is simple and useful to make comparative studies, it does not describe adequately the drug release kinetics in the eye, considering the small tear volume and flow rates found in vivo. In this work, a microfluidic cell was designed and used to mimic the continuous, volumetric flow rate of tear fluid and its low volume. The suitable operation of the cell, in terms of uniformity and symmetry of flux, was proved using a numerical model based in the Navier-Stokes and continuity equations. The release profile of a model system (a hydroxyethyl methacrylate-based hydrogel (HEMA/PVP) for soft contact lenses (SCLs) loaded with diclofenac) obtained with the microfluidic cell was compared with that obtained in static conditions, showing that the kinetics of release in dynamic conditions is slower. The application of the numerical model demonstrated that the designed cell can be used to simulate the drug release in the whole range of the human eye tear film volume and allowed to estimate the drug concentration in the volume of liquid in direct contact with the hydrogel. The knowledge of this concentration, which is significantly different from that measured in the experimental tests during the first hours of release, is critical to predict the toxicity of the drug release system and its in vivo efficacy. In conclusion, the use of the microfluidic cell in conjunction with the numerical model shall be a valuable tool to design and optimize new therapeutic drug-loaded SCLs.

  10. Reproducibility of isotope ratio measurements

    International Nuclear Information System (INIS)

    Elmore, D.

    1981-01-01

    The use of an accelerator as part of a mass spectrometer has improved the sensitivity for measuring low levels of long-lived radionuclides by several orders of magnitude. However, the complexity of a large tandem accelerator and beam transport system has made it difficult to match the precision of low energy mass spectrometry. Although uncertainties for accelerator measured isotope ratios as low as 1% have been obtained under favorable conditions, most errors quoted in the literature for natural samples are in the 5 to 20% range. These errors are dominated by statistics and generally the reproducibility is unknown since the samples are only measured once

  11. Reproducing American Sign Language Sentences: Cognitive Scaffolding in Working Memory

    Directory of Open Access Journals (Sweden)

    Ted eSupalla

    2014-08-01

    Full Text Available The American Sign Language Sentence Reproduction Test (ASL-SRT requires the precise reproduction of a series of ASL sentences increasing in complexity and length. Error analyses of such tasks provides insight into working memory and scaffolding processes. Data was collected from three groups expected to differ in fluency: deaf children, deaf adults and hearing adults, all users of ASL. Quantitative (correct/incorrect recall and qualitative error analyses were performed. Percent correct on the reproduction task supports its sensitivity to fluency as test performance clearly differed across the three groups studied. A linguistic analysis of errors further documented differing strategies and bias across groups. Subjects’ recall projected the affordance and constraints of deep linguistic representations to differing degrees, with subjects resorting to alternate processing strategies in the absence of linguistic knowledge. A qualitative error analysis allows us to capture generalizations about the relationship between error pattern and the cognitive scaffolding, which governs the sentence reproduction process. Highly fluent signers and less-fluent signers share common chokepoints on particular words in sentences. However, they diverge in heuristic strategy. Fluent signers, when they make an error, tend to preserve semantic details while altering morpho-syntactic domains. They produce syntactically correct sentences with equivalent meaning to the to-be-reproduced one, but these are not verbatim reproductions of the original sentence. In contrast, less-fluent signers tend to use a more linear strategy, preserving lexical status and word ordering while omitting local inflections, and occasionally resorting to visuo-motoric imitation. Thus, whereas fluent signers readily use top-down scaffolding in their working memory, less fluent signers fail to do so. Implications for current models of working memory across spoken and signed modalities are

  12. Immortalized keratinocytes derived from patients with epidermolytic ichthyosis reproduce the disease phenotype: a useful in vitro model for testing new treatments.

    Science.gov (United States)

    Chamcheu, J C; Pihl-Lundin, I; Mouyobo, C E; Gester, T; Virtanen, M; Moustakas, A; Navsaria, H; Vahlquist, A; Törmä, H

    2011-02-01

    Epidermolytic ichthyosis (EI) is a skin fragility disorder caused by mutations in genes encoding suprabasal keratins 1 and 10. While the aetiology of EI is known, model systems are needed for pathophysiological studies and development of novel therapies. To generate immortalized keratinocyte lines from patients with EI for studies of EI cell pathology and the effects of chemical chaperones as putative therapies. We derived keratinocytes from three patients with EI and one healthy control and established immortalized keratinocytes using human papillomavirus 16-E6/E7. Growth and differentiation characteristics, ability to regenerate organotypic epidermis, keratin expression, formation of cytoskeletal aggregates, and responses to heat shock and chemical chaperones were assessed. The cell lines EH11 (K1_p.Val176_Lys197del), EH21 (K10_p.156Arg>Gly), EH31 (K10_p.Leu161_Asp162del) and NKc21 (wild-type) currently exceed 160 population doublings and differentiate when exposed to calcium. At resting state, keratin aggregates were detected in 9% of calcium-differentiated EH31 cells, but not in any other cell line. Heat stress further increased this proportion to 30% and also induced aggregates in 3% of EH11 cultures. Treatment with trimethylamine N-oxide and 4-phenylbutyrate (4-PBA) reduced the fraction of aggregate-containing cells and affected the mRNA expression of keratins 1 and 10 while 4-PBA also modified heat shock protein 70 (HSP70) expression. Furthermore, in situ proximity ligation assay suggested a colocalization between HSP70 and keratins 1 and 10. Reconstituted epidermis from EI cells cornified but EH21 and EH31 cells produced suprabasal cytolysis, closely resembling the in vivo phenotype. These immortalized cell lines represent a useful model for studying EI biology and novel therapies. © 2011 The Authors. BJD © 2011 British Association of Dermatologists.

  13. Qualitative analysis of cosmological models in Brans-Dicke theory, solutions from non-minimal coupling and viscous universe

    International Nuclear Information System (INIS)

    Romero Filho, C.A.

    1988-01-01

    Using dynamical system theory we investigate homogeneous and isotropic models in Brans-Dicke theory for perfect fluids with general equation of state and arbitrary ω. Phase diagrams are drawn on the Poincare sphere which permits a qualitative analysis of the models. Based on this analysis we construct a method for generating classes of solutions in Brans-Dicke theory. The same technique is used for studying models arising from non-minimal coupling of electromagnetism with gravity. In addition, viscous fluids are considered and non-singular solutions with bulk viscosity are found. (author)

  14. Qualitative Analysis of a Diffusive Ratio-Dependent Holling-Tanner Predator-Prey Model with Smith Growth

    Directory of Open Access Journals (Sweden)

    Zongmin Yue

    2013-01-01

    Full Text Available We investigated the dynamics of a diffusive ratio-dependent Holling-Tanner predator-prey model with Smith growth subject to zero-flux boundary condition. Some qualitative properties, including the dissipation, persistence, and local and global stability of positive constant solution, are discussed. Moreover, we give the refined a priori estimates of positive solutions and derive some results for the existence and nonexistence of nonconstant positive steady state.

  15. A Mouse Model That Reproduces the Developmental Pathways and Site Specificity of the Cancers Associated With the Human BRCA1 Mutation Carrier State

    Directory of Open Access Journals (Sweden)

    Ying Liu

    2015-10-01

    Full Text Available Predisposition to breast and extrauterine Müllerian carcinomas in BRCA1 mutation carriers is due to a combination of cell-autonomous consequences of BRCA1 inactivation on cell cycle homeostasis superimposed on cell-nonautonomous hormonal factors magnified by the effects of BRCA1 mutations on hormonal changes associated with the menstrual cycle. We used the Müllerian inhibiting substance type 2 receptor (Mis2r promoter and a truncated form of the Follicle stimulating hormone receptor (Fshr promoter to introduce conditional knockouts of Brca1 and p53 not only in mouse mammary and Müllerian epithelia, but also in organs that control the estrous cycle. Sixty percent of the double mutant mice developed invasive Müllerian and mammary carcinomas. Mice carrying heterozygous mutations in Brca1 and p53 also developed invasive tumors, albeit at a lesser (30% rate, in which the wild type alleles were no longer present due to loss of heterozygosity. While mice carrying heterozygous mutations in both genes developed mammary tumors, none of the mice carrying only a heterozygous p53 mutation developed such tumors (P < 0.0001, attesting to a role for Brca1 mutations in tumor development. This mouse model is attractive to investigate cell-nonautonomous mechanisms associated with cancer predisposition in BRCA1 mutation carriers and to investigate the merit of chemo-preventive drugs targeting such mechanisms.

  16. Qualitative and quantitative combined nonlinear dynamics model and its application in analysis of price, supply–demand ratio and selling rate

    International Nuclear Information System (INIS)

    Zhu, Dingju

    2016-01-01

    The qualitative and quantitative combined nonlinear dynamics model proposed in this paper fill the gap in nonlinear dynamics model in terms of qualitative and quantitative combined methods, allowing the qualitative model and quantitative model to perfectly combine and overcome their weaknesses by learning from each other. These two types of models use their strengths to make up for the other’s deficiencies. The qualitative and quantitative combined models can surmount the weakness that the qualitative model cannot be applied and verified in a quantitative manner, and the high costs and long time of multiple construction as well as verification of the quantitative model. The combined model is more practical and efficient, which is of great significance for nonlinear dynamics. The qualitative and quantitative combined modeling and model analytical method raised in this paper is not only applied to nonlinear dynamics, but can be adopted and drawn on in the modeling and model analysis of other fields. Additionally, the analytical method of qualitative and quantitative combined nonlinear dynamics model proposed in this paper can satisfactorily resolve the problems with the price system’s existing nonlinear dynamics model analytical method. The three-dimensional dynamics model of price, supply–demand ratio and selling rate established in this paper make estimates about the best commodity prices using the model results, thereby providing a theoretical basis for the government’s macro-control of price. Meanwhile, this model also offer theoretical guidance to how to enhance people’s purchasing power and consumption levels through price regulation and hence to improve people’s living standards.

  17. Evaluation of the agonist PET radioligand [¹¹C]GR103545 to image kappa opioid receptor in humans: kinetic model selection, test-retest reproducibility and receptor occupancy by the antagonist PF-04455242.

    Science.gov (United States)

    Naganawa, Mika; Jacobsen, Leslie K; Zheng, Ming-Qiang; Lin, Shu-Fei; Banerjee, Anindita; Byon, Wonkyung; Weinzimmer, David; Tomasi, Giampaolo; Nabulsi, Nabeel; Grimwood, Sarah; Badura, Lori L; Carson, Richard E; McCarthy, Timothy J; Huang, Yiyun

    2014-10-01

    Kappa opioid receptors (KOR) are implicated in several brain disorders. In this report, a first-in-human positron emission tomography (PET) study was conducted with the potent and selective KOR agonist tracer, [(11)C]GR103545, to determine an appropriate kinetic model for analysis of PET imaging data and assess the test-retest reproducibility of model-derived binding parameters. The non-displaceable distribution volume (V(ND)) was estimated from a blocking study with naltrexone. In addition, KOR occupancy of PF-04455242, a selective KOR antagonist that is active in preclinical models of depression, was also investigated. For determination of a kinetic model and evaluation of test-retest reproducibility, 11 subjects were scanned twice with [(11)C]GR103545. Seven subjects were scanned before and 75 min after oral administration of naltrexone (150 mg). For the KOR occupancy study, six subjects were scanned at baseline and 1.5 h and 8 h after an oral dose of PF-04455242 (15 mg, n=1 and 30 mg, n=5). Metabolite-corrected arterial input functions were measured and all scans were 150 min in duration. Regional time-activity curves (TACs) were analyzed with 1- and 2-tissue compartment models (1TC and 2TC) and the multilinear analysis (MA1) method to derive regional volume of distribution (V(T)). Relative test-retest variability (TRV), absolute test-retest variability (aTRV) and intra-class coefficient (ICC) were calculated to assess test-retest reproducibility of regional VT. Occupancy plots were computed for blocking studies to estimate occupancy and V(ND). The half maximal inhibitory concentration (IC50) of PF-04455242 was determined from occupancies and drug concentrations in plasma. [(11)C]GR103545 in vivo K(D) was also estimated. Regional TACs were well described by the 2TC model and MA1. However, 2TC VT was sometimes estimated with high standard error. Thus MA1 was the model of choice. Test-retest variability was ~15%, depending on the outcome measure. The blocking

  18. Using a nursing theory or a model in nursing PhD dissertations: a qualitative study from Turkey.

    Science.gov (United States)

    Mete, Samiye; Gokçe İsbir, Gozde

    2015-04-01

    The aim of this study was to reveal experiences of nursing students and their advisors using theories and models in their PhD dissertations. The study adopted a descriptive qualitative approach. This study was performed with 10 PhD candidates and their five advisors from nursing faculty. The results of the study were categorized into four. These are reasons for using a theory/model in a PhD dissertation, reasons for preferring a given model, causes of difficulties in using models in PhD dissertations, and facilitating factors of using theories and models in PhD of dissertations. It was also reported to contribute to the methodology of research and professional development of the students and advisors. © 2014 NANDA International, Inc.

  19. Reproducibility in Research: Systems, Infrastructure, Culture

    Directory of Open Access Journals (Sweden)

    Tom Crick

    2017-11-01

    Full Text Available The reproduction and replication of research results has become a major issue for a number of scientific disciplines. In computer science and related computational disciplines such as systems biology, the challenges closely revolve around the ability to implement (and exploit novel algorithms and models. Taking a new approach from the literature and applying it to a new codebase frequently requires local knowledge missing from the published manuscripts and transient project websites. Alongside this issue, benchmarking, and the lack of open, transparent and fair benchmark sets present another barrier to the verification and validation of claimed results. In this paper, we outline several recommendations to address these issues, driven by specific examples from a range of scientific domains. Based on these recommendations, we propose a high-level prototype open automated platform for scientific software development which effectively abstracts specific dependencies from the individual researcher and their workstation, allowing easy sharing and reproduction of results. This new e-infrastructure for reproducible computational science offers the potential to incentivise a culture change and drive the adoption of new techniques to improve the quality and efficiency – and thus reproducibility – of scientific exploration.

  20. The persistence of subsistence: qualitative social-ecological modeling of indigenous aquatic hunting and gathering in tropical Australia

    Directory of Open Access Journals (Sweden)

    Marcus Barber

    2015-03-01

    Full Text Available Subsistence remains critical to indigenous people in settler-colonial states such as Australia, providing key foundations for indigenous identities and for wider state recognition. However, the drivers of contemporary subsistence are rarely fully articulated and analyzed in terms of likely changing conditions. Our interdisciplinary team combined past research experience gained from multiple sites with published literature to create two generalized qualitative models of the socio-cultural and environmental influences on indigenous aquatic subsistence in northern Australia. One model focused on the longer term (inter-year to generational persistence of subsistence at the community scale, the other model on shorter term (day to season drivers of effort by active individuals. The specification of driver definitions and relationships demonstrates the complexities of even generalized and materialist models of contemporary subsistence practices. The qualitative models were analyzed for emergent properties and for responses to plausible changes in key variables: access, habitat degradation, social security availability, and community dysfunction. Positive human community condition is shown to be critical to the long-term persistence of subsistence, but complex interactions of negative and positive drivers shape subsistence effort expended at the individual scale and within shorter time frames. Such models enable motivations, complexities, and the potential management and policy levers of significance to be identified, defined, causally related, and debated. The models can be used to augment future models of human-natural systems, be tested against case-specific field conditions and/or indigenous perspectives, and aid preliminary assessments of the effects on subsistence of changes in social and environmental conditions, including policy settings.

  1. Qualitative Content Analysis

    OpenAIRE

    Philipp Mayring

    2000-01-01

    The article describes an approach of systematic, rule guided qualitative text analysis, which tries to preserve some methodological strengths of quantitative content analysis and widen them to a concept of qualitative procedure. First the development of content analysis is delineated and the basic principles are explained (units of analysis, step models, working with categories, validity and reliability). Then the central procedures of qualitative content analysis, inductive development of ca...

  2. Multiple methods for multiple futures: Integrating qualitative scenario planning and quantitative simulation modeling for natural resource decision making

    Science.gov (United States)

    Symstad, Amy J.; Fisichelli, Nicholas A.; Miller, Brian W.; Rowland, Erika; Schuurman, Gregor W.

    2017-01-01

    Scenario planning helps managers incorporate climate change into their natural resource decision making through a structured “what-if” process of identifying key uncertainties and potential impacts and responses. Although qualitative scenarios, in which ecosystem responses to climate change are derived via expert opinion, often suffice for managers to begin addressing climate change in their planning, this approach may face limits in resolving the responses of complex systems to altered climate conditions. In addition, this approach may fall short of the scientific credibility managers often require to take actions that differ from current practice. Quantitative simulation modeling of ecosystem response to climate conditions and management actions can provide this credibility, but its utility is limited unless the modeling addresses the most impactful and management-relevant uncertainties and incorporates realistic management actions. We use a case study to compare and contrast management implications derived from qualitative scenario narratives and from scenarios supported by quantitative simulations. We then describe an analytical framework that refines the case study’s integrated approach in order to improve applicability of results to management decisions. The case study illustrates the value of an integrated approach for identifying counterintuitive system dynamics, refining understanding of complex relationships, clarifying the magnitude and timing of changes, identifying and checking the validity of assumptions about resource responses to climate, and refining management directions. Our proposed analytical framework retains qualitative scenario planning as a core element because its participatory approach builds understanding for both managers and scientists, lays the groundwork to focus quantitative simulations on key system dynamics, and clarifies the challenges that subsequent decision making must address.

  3. Theory of reproducing kernels and applications

    CERN Document Server

    Saitoh, Saburou

    2016-01-01

    This book provides a large extension of the general theory of reproducing kernels published by N. Aronszajn in 1950, with many concrete applications. In Chapter 1, many concrete reproducing kernels are first introduced with detailed information. Chapter 2 presents a general and global theory of reproducing kernels with basic applications in a self-contained way. Many fundamental operations among reproducing kernel Hilbert spaces are dealt with. Chapter 2 is the heart of this book. Chapter 3 is devoted to the Tikhonov regularization using the theory of reproducing kernels with applications to numerical and practical solutions of bounded linear operator equations. In Chapter 4, the numerical real inversion formulas of the Laplace transform are presented by applying the Tikhonov regularization, where the reproducing kernels play a key role in the results. Chapter 5 deals with ordinary differential equations; Chapter 6 includes many concrete results for various fundamental partial differential equations. In Chapt...

  4. Governance arrangements for IT project portfolio management qualitative insights and a quantitative modeling approach

    CERN Document Server

    Frey, Thorsten

    2014-01-01

    Due to the growing importance of IT-based innovations, contemporary firms face an excessive number of proposals for IT projects. As typically only a fraction of these projects can be implemented with the given capacity, IT project portfolio management as a relatively new discipline has received growing attention in research and practice in recent years.?Thorsten Frey demonstrates how companies are struggling to find the right balance between local autonomy and central overview about all projects in the organization. In this context, impacts of different contextual factors on the design of governance arrangements for IT project portfolio management are demonstrated. Moreover, consequences of the use of different organizational designs are analyzed. The author presents insights from a qualitative empirical study as well as a simulative approach.

  5. Methods for partial differential equations qualitative properties of solutions, phase space analysis, semilinear models

    CERN Document Server

    Ebert, Marcelo R

    2018-01-01

    This book provides an overview of different topics related to the theory of partial differential equations. Selected exercises are included at the end of each chapter to prepare readers for the “research project for beginners” proposed at the end of the book. It is a valuable resource for advanced graduates and undergraduate students who are interested in specializing in this area. The book is organized in five parts: In Part 1 the authors review the basics and the mathematical prerequisites, presenting two of the most fundamental results in the theory of partial differential equations: the Cauchy-Kovalevskaja theorem and Holmgren's uniqueness theorem in its classical and abstract form. It also introduces the method of characteristics in detail and applies this method to the study of Burger's equation. Part 2 focuses on qualitative properties of solutions to basic partial differential equations, explaining the usual properties of solutions to elliptic, parabolic and hyperbolic equations for the archetypes...

  6. Perspectives on econometric modelling to inform policy: a UK qualitative case study of minimum unit pricing of alcohol.

    Science.gov (United States)

    Katikireddi, Srinivasa V; Bond, Lyndal; Hilton, Shona

    2014-06-01

    Novel policy interventions may lack evaluation-based evidence. Considerations to introduce minimum unit pricing (MUP) of alcohol in the UK were informed by econometric modelling (the 'Sheffield model'). We aim to investigate policy stakeholders' views of the utility of modelling studies for public health policy. In-depth qualitative interviews with 36 individuals involved in MUP policy debates (purposively sampled to include civil servants, politicians, academics, advocates and industry-related actors) were conducted and thematically analysed. Interviewees felt familiar with modelling studies and often displayed detailed understandings of the Sheffield model. Despite this, many were uneasy about the extent to which the Sheffield model could be relied on for informing policymaking and preferred traditional evaluations. A tension was identified between this preference for post hoc evaluations and a desire for evidence derived from local data, with modelling seen to offer high external validity. MUP critics expressed concern that the Sheffield model did not adequately capture the 'real life' world of the alcohol market, which was conceptualized as a complex and, to some extent, inherently unpredictable system. Communication of modelling results was considered intrinsically difficult but presenting an appropriate picture of the uncertainties inherent in modelling was viewed as desirable. There was general enthusiasm for increased use of econometric modelling to inform future policymaking but an appreciation that such evidence should only form one input into the process. Modelling studies are valued by policymakers as they provide contextually relevant evidence for novel policies, but tensions exist with views of traditional evaluation-based evidence. © The Author 2013. Published by Oxford University Press on behalf of the European Public Health Association.

  7. Numerical and Qualitative Contrasts of Two Statistical Models for Water Quality Change in Tidal Waters

    Science.gov (United States)

    Two statistical approaches, weighted regression on time, discharge, and season and generalized additive models, have recently been used to evaluate water quality trends in estuaries. Both models have been used in similar contexts despite differences in statistical foundations and...

  8. A new approach to testing an integrated water systems model using qualitative scenarios

    NARCIS (Netherlands)

    Giang, N.T.; de Kok, Jean-Luc; Titus, M.J.

    2007-01-01

    Integrated systems models have been developed over decades, aiming to support the decision-makers in the planning and managing of natural resources. The inherent model complexity, lack of knowledge about the linkages among model components, scarcity of field data, and uncertainty involved with

  9. Perspectives on econometric modelling to inform policy: a UK qualitative case study of minimum unit pricing of alcohol

    Science.gov (United States)

    Bond, Lyndal; Hilton, Shona

    2014-01-01

    Background: Novel policy interventions may lack evaluation-based evidence. Considerations to introduce minimum unit pricing (MUP) of alcohol in the UK were informed by econometric modelling (the ‘Sheffield model’). We aim to investigate policy stakeholders’ views of the utility of modelling studies for public health policy. Methods: In-depth qualitative interviews with 36 individuals involved in MUP policy debates (purposively sampled to include civil servants, politicians, academics, advocates and industry-related actors) were conducted and thematically analysed. Results: Interviewees felt familiar with modelling studies and often displayed detailed understandings of the Sheffield model. Despite this, many were uneasy about the extent to which the Sheffield model could be relied on for informing policymaking and preferred traditional evaluations. A tension was identified between this preference for post hoc evaluations and a desire for evidence derived from local data, with modelling seen to offer high external validity. MUP critics expressed concern that the Sheffield model did not adequately capture the ‘real life’ world of the alcohol market, which was conceptualized as a complex and, to some extent, inherently unpredictable system. Communication of modelling results was considered intrinsically difficult but presenting an appropriate picture of the uncertainties inherent in modelling was viewed as desirable. There was general enthusiasm for increased use of econometric modelling to inform future policymaking but an appreciation that such evidence should only form one input into the process. Conclusion: Modelling studies are valued by policymakers as they provide contextually relevant evidence for novel policies, but tensions exist with views of traditional evaluation-based evidence. PMID:24367068

  10. Women's maternity care needs and related service models in rural areas: A comprehensive systematic review of qualitative evidence.

    Science.gov (United States)

    Hoang, Ha; Le, Quynh; Ogden, Kathryn

    2014-12-01

    Understanding the needs of rural women in maternity care and service models available to them is significant for the development of effective policies and the sustainability of rural communities. Nevertheless, no systematic review of studies addressing these needs has been conducted. To synthesise the best available evidence on the experiences of women's needs in maternity care and existing service models in rural areas. Literature search of ten electronic databases, digital theses, and reference lists of relevant studies applying inclusion/exclusion criteria was conducted. Selected papers were assessed using standardised critical appraisal instruments from JBI-QARI. Data extracted from these studies were synthesised using thematic synthesis. 12 studies met the inclusion criteria. There were three main themes and several sub-themes identified. A comprehensive set of the maternity care expectations of rural women was reported in this review including safety (7), continuity of care (6) and quality of care (6), and informed choices needs (4). In addition, challenges in accessing maternity services also emerged from the literature such as access (6), risk of travelling (9) and associated cost of travel (9). Four models of maternity care examined in the literature were medically led care (5), GP-led care (4), midwifery-led care (7) and home birth (6). The systematic review demonstrates the importance of including well-conducted qualitative studies in informing the development of evidence-based policies to address women's maternity care needs and inform service models. Synthesising the findings from qualitative studies offers important insight for informing effective public health policy. Copyright © 2014 Australian College of Midwives. Published by Elsevier Ltd. All rights reserved.

  11. GIS-Based Fast Moving Landslide Risk Analysis Model Using Qualitative Approach: A Case Study of Balakot, Pakistan

    Directory of Open Access Journals (Sweden)

    Abdul Salam Soomro

    2011-04-01

    Full Text Available The innovation of this research is the development of new model called fast moving landslide risk analysis model by modifying one of the previous prominent landslide risk algorithms focusing on the fast moving type of the landslides (such as mudslides, mud flows, block slide, rock fall and topple based on the qualitative approach using Heuristic method in GIS (Geographical Information Systems. The different event controlling parameters and criteria were used for fast moving landslide predictive risk model. The pair wise comparison method was used in which the parameters of landslide hazard and vulnerability were compared by their assigned weights. The drawback of the used approach was justified by the standard value of consistency ratio, which proved the assigned weight of the parameters as reasonable and consistent. The model was validated by using the occurred landslides inventory data and correlation coefficient test, which showed the positive relationship between the landslide risk predicted regions and the occurred landslides locations. The various landslide events occurred on 8th October, 2005 were accumulated as landslide inventory by the interpretation of satellite imagery. The validation of the model was justified by using one of the statistical two paired, \\"t\\" test, and the amount of the predicted risk in the different regions. It is believed that this modified model will prove beneficial to the decision makers in future.

  12. Three models of child abuse consultations: A qualitative study of inpatient child abuse consultation notes.

    Science.gov (United States)

    Keenan, Heather T; Campbell, Kristine A

    2015-05-01

    Child abuse pediatricians have multiple roles in caring for abused children, including prevention, diagnosis, treatment, and, when needed, expert legal opinion. The child physical abuse consultation differs from the traditional medical consultation in that it has medical, investigative and legal audiences, all of whom have different information needs. How child abuse pediatricians approach their cases and how they document their initial inpatient consultations that will be used by such a diverse audience is currently unexplored. We used content analysis to examine 37 child physical abuse consultation notes from a national sample of child abuse pediatricians in order to understand physicians' approaches to these consultations. Three commonly used models of child physical abuse consultation were identified in the data that we named the base model, the investigative model, and the family-dynamic model. While model types overlap, each is distinguished by key features including the approach used to gather information, the information recorded, and the language used in documentation. The base model most closely mirrors the traditional medical approach; the investigative model concentrates on triangulation of sources of information; and, the family-dynamic model concentrates on physician perceptions of family relationships. The three models of consultations for child physical abuse mirror the areas of child abuse pediatrics: diagnostic, forensic and therapeutic. These models are considered in relationship to best practice from other medical specialties with forensic components. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. [Qualitative evaluation of the alcoholism integral approach with the GIA model (alcoholism institutional groups)].

    Science.gov (United States)

    Villafañe, Claudia I

    2009-01-01

    This paper presents the evaluation, over a period of 6 years, on the effectiveness of the Alcoholism Institutional Group (GIA), in the Puerto San Julián Hospital, Santa Cruz, Argentina. The theoretical framework refers to three aspects: subject, social and institutional order. The qualitative logic and the process of analytic induction were used. information was gathered through semi-structured interviews to selected cases (intentional sampling). The constant comparative method for the analysis was used. the GIA method is effective from the aspects of the subject and the social order; the subject included in the treatment was able to: a) deconstruct the socially assumed role as an alcoholic, b) reconstruct their identity, c) restore the fabric of family, labour and social links, d) identify the healthy aspects of their personality to recover the capacities obstructed by the illness, e) learn to solve conflicts collectively thanks to group functioning, f) report to destigmatize the illness, and g) develop a healthy life project. The GIA method proved partially effective from the institutional angle; the task succeeded in uncovering, affirming and working on alcoholism as an illness within the hospital setting, but with less involvement than other local institutions, which motivated projects and strategies started from the results of this research.

  14. Qualitative Prediction of Isotope Abundances with the Bipolar Model of Oscillations in a Chain System

    Directory of Open Access Journals (Sweden)

    Ries A.

    2015-04-01

    Full Text Available We analyzed the individual masses of non-radioactive isotopes of the chemical elements with an extended version of the bipolar model of oscillations in a chain system. When defining a small set of appropriate rules, the model is able to predict the isotope which possesses the highest abundance. This information can be read out from the continued fraction representations of the isotope masses. Isotopes with enhanced nuclear stability due to a magic number of neutrons in the nucleus were frequently found as exceptions from the model. The model is applicable to the di-, tri- and tetranuclidic chemical ele- ments; it fails completely as soon as a chemical element is composed of 5 or more stable isotopes. From this we conclude that the bipolar model of oscillations in a chain system – in its present form – is not yet the final version; the model must still be extended.

  15. Reproducibility of surface roughness in reaming

    DEFF Research Database (Denmark)

    Müller, Pavel; De Chiffre, Leonardo

    An investigation on the reproducibility of surface roughness in reaming was performed to document the applicability of this approach for testing cutting fluids. Austenitic stainless steel was used as a workpiece material and HSS reamers as cutting tools. Reproducibility of the results was evaluat...

  16. Examination of reproducibility in microbiological degredation experiments

    DEFF Research Database (Denmark)

    Sommer, Helle Mølgaard; Spliid, Henrik; Holst, Helle

    1998-01-01

    Experimental data indicate that certain microbiological degradation experiments have a limited reproducibility. Nine identical batch experiments were carried out on 3 different days to examine reproducibility. A pure culture, isolated from soil, grew with toluene as the only carbon and energy...

  17. Reproducible statistical analysis with multiple languages

    DEFF Research Database (Denmark)

    Lenth, Russell; Højsgaard, Søren

    2011-01-01

    This paper describes the system for making reproducible statistical analyses. differs from other systems for reproducible analysis in several ways. The two main differences are: (1) Several statistics programs can be in used in the same document. (2) Documents can be prepared using OpenOffice or ...

  18. A Qualitative Examination of the Importance of Female Role Models in Investment Banks

    OpenAIRE

    Sealy, Ruth

    2009-01-01

    A number of practitioner surveys across a range of industries have cited the lack of senior female role models as a barrier to career progression. There is very little academic literature to explain this at a senior organizational level. An initial review of the extant role model literature led to the inclusion of two further related areas – organizational demographics, as a contextual factor affecting the availability of role models, and work identity development as a link bet...

  19. [Nursing practice based on theoretical models: a qualitative study of nurses' perception].

    Science.gov (United States)

    Amaducci, Giovanna; Iemmi, Marina; Prandi, Marzia; Saffioti, Angelina; Carpanoni, Marika; Mecugni, Daniela

    2013-01-01

    Many faculty argue that theory and theorizing are closely related to the clinical practice, that the disciplinary knowledge grows, more relevantly, from the specific care context in which it takes place and, moreover, that knowledge does not proceed only by the application of general principles of the grand theories to specific cases. Every nurse, in fact, have  a mental model, of what may or may not be aware, that motivate and substantiate every action and choice of career. The study describes what the nursing theoretical model is; the mental model and the tacit  knowledge underlying it. It identifies the explicit theoretical model of the professional group that rapresents nursing partecipants, aspects of continuity with the theoretical model proposed by this degree course in Nursing.. Methods Four focus groups were made which were attended by a total of 22 nurses, rapresentatives of almost every Unit of Reggio Emilia Hospital's. We argue that the theoretical nursing model of each professional group is the result of tacit knowledge, which help to define the personal mental model, and the theoretical model, which explicitly underlying theoretical content learned applied consciously and reverted to / from nursing practice. Reasoning on the use of theory in practice has allowed us to give visibility to a theoretical model explicitly nursing authentically oriented to the needs of the person, in all its complexity in specific contexts.

  20. Model endophenotype for bipolar disorder: Qualitative Analysis, etiological factors, and research areas

    Directory of Open Access Journals (Sweden)

    Naraiana de Oliveira Tavares

    2014-12-01

    Full Text Available The aim of this study is to present an updated view of the writings on the endophenotype model for bipolar disorder using analytical methodologies. A review and analysis of networks was performed through descriptors and keywords that characterize the composition of the endophenotype model as a model of health. Information was collected from between 1992 and 2014, and the main thematic areas covered in the articles were identified. We discuss the results and question their cohesion, emphasizing the need to strengthen and identify the points of connection between etiological factors and characteristics that make up the model of endophenotypes for bipolar disorder.

  1. Reproducibility principles, problems, practices, and prospects

    CERN Document Server

    Maasen, Sabine

    2016-01-01

    Featuring peer-reviewed contributions from noted experts in their fields of research, Reproducibility: Principles, Problems, Practices, and Prospects presents state-of-the-art approaches to reproducibility, the gold standard sound science, from multi- and interdisciplinary perspectives. Including comprehensive coverage for implementing and reflecting the norm of reproducibility in various pertinent fields of research, the book focuses on how the reproducibility of results is applied, how it may be limited, and how such limitations can be understood or even controlled in the natural sciences, computational sciences, life sciences, social sciences, and studies of science and technology. The book presents many chapters devoted to a variety of methods and techniques, as well as their epistemic and ontological underpinnings, which have been developed to safeguard reproducible research and curtail deficits and failures. The book also investigates the political, historical, and social practices that underlie repro...

  2. [Implementation of the new clinical practice training model in Andalusia: a qualitative evaluation of the Nursing and Physiotherapy degrees].

    Science.gov (United States)

    Fernández-Sola, Cayetano; Granero-Molina, José; Márquez-Membrive, Josefa; Aguilera-Manrique, Gabriel; Castro-Sánchez, Adelaida M

    2014-01-01

    The design of new Bachelor degree courses, together with the agreement reached between the Regional Government of Andalusia and Andalusian universities shape the new clinical training model for Health Science students. The aim of this project is to present a qualitative evaluation of the implementation of the new model in Nursing and Physiotherapy degrees at the University of Almeria and the Andalusian Public Health System. An exploratory qualitative study using document content analysis techniques, by analyzing 12 reports from teachers and those responsible for Practicum in Nursing and Physiotherapy degrees at the University of Almeria. The reports included opinions and proposals from university and clinical placement teachers, healthcare professionals or clinical placement tutors, students, and those in positions of responsibility as regards clinical placements. Three categories emerged in the data analysis: Health system organization, with sub-categories of disparity between shifts, difficulties with supervisor coordination, feelings of a lack of control, disparities in evaluation criteria and geographic distribution; academic organization, with sub-categories of short rotations, a lack of information received by the clinical placement tutor, and carrying out placements without studying the theory; and management of the work agreement, with sub-categories of being discouraged by what is received in return, extra work for those in charge, and delays in evaluations. The study suggests a need to support and guide clinical tutors, to increase coordination between the university and health services, to organize the students' theoretical and practical training and to provide the management of the model with flexibility and transparency. Copyright © 2013 Elsevier España, S.L. All rights reserved.

  3. A qualitative model of Riacho Fundo (DF, Brazil) water basin sustainability

    NARCIS (Netherlands)

    Salles, P.; Bredeweg, B.

    2009-01-01

    This paper presents a model aiming at supporting stakeholders to improve their understanding of the effects of land use changes using the Brazilian Riacho Fundo water basin as a case study. The paper makes two contributions: it presents a model about sustainability in a small tropical water basin,

  4. Modeling grain boundaries in polycrystals using cohesive elements: Qualitative and quantitative analysis

    International Nuclear Information System (INIS)

    El Shawish, Samir; Cizelj, Leon; Simonovski, Igor

    2013-01-01

    Highlights: ► We estimate the performance of cohesive elements for modeling grain boundaries. ► We compare the computed stresses in ABAQUS finite element solver. ► Tests are performed in analytical and realistic models of polycrystals. ► Most severe issue is found within the plastic grain response. ► Other identified issues are related to topological constraints in modeling space. -- Abstract: We propose and demonstrate several tests to estimate the performance of the cohesive elements in ABAQUS for modeling grain boundaries in complex spatial structures such as polycrystalline aggregates. The performance of the cohesive elements is checked by comparing the computed stresses with the theoretically predicted values for a homogeneous material under uniaxial tensile loading. Statistical analyses are performed under different loading conditions for two elasto-plastic models of the grains: isotropic elasticity with isotropic hardening plasticity and anisotropic elasticity with crystal plasticity. Tests are conducted on an analytical finite element model generated from Voronoi tessellation as well as on a realistic finite element model of a stainless steel wire. The results of the analyses highlight several issues related to the computation of normal and shear stresses. The most severe issue is found within the plastic grain response where the computed normal stresses on a particularly oriented cohesive elements are significantly underestimated. Other issues are found to be related to topological constraints in the modeling space and result in the increased scatter of the computed stresses

  5. A Model for Using Qualitative Variables as Covariates in the Analysis of Covariance. Technical Paper 266.

    Science.gov (United States)

    Ross, N. Phillip

    The U.S. Army Research Institute for the Behavioral and Social Sciences has developed a wide range of statistical models to test hypotheses generated in relation to an equally wide range of measurement and evaluation situations. The randomized block (RB) design has traditionally been a preferred model for much psychological research. The RB has…

  6. Simplified Qualitative Discrete Numerical Model to Determine Cracking Pattern in Brittle Materials by Means of Finite Element Method

    Directory of Open Access Journals (Sweden)

    J. Ochoa-Avendaño

    2017-01-01

    Full Text Available This paper presents the formulation, implementation, and validation of a simplified qualitative model to determine the crack path of solids considering static loads, infinitesimal strain, and plane stress condition. This model is based on finite element method with a special meshing technique, where nonlinear link elements are included between the faces of the linear triangular elements. The stiffness loss of some link elements represents the crack opening. Three experimental tests of bending beams are simulated, where the cracking pattern calculated with the proposed numerical model is similar to experimental result. The advantages of the proposed model compared to discrete crack approaches with interface elements can be the implementation simplicity, the numerical stability, and the very low computational cost. The simulation with greater values of the initial stiffness of the link elements does not affect the discontinuity path and the stability of the numerical solution. The exploded mesh procedure presented in this model avoids a complex nonlinear analysis and regenerative or adaptive meshes.

  7. Qualitative analysis of a discrete thermostatted kinetic framework modeling complex adaptive systems

    Science.gov (United States)

    Bianca, Carlo; Mogno, Caterina

    2018-01-01

    This paper deals with the derivation of a new discrete thermostatted kinetic framework for the modeling of complex adaptive systems subjected to external force fields (nonequilibrium system). Specifically, in order to model nonequilibrium stationary states of the system, the external force field is coupled to a dissipative term (thermostat). The well-posedness of the related Cauchy problem is investigated thus allowing the new discrete thermostatted framework to be suitable for the derivation of specific models and the related computational analysis. Applications to crowd dynamics and future research directions are also discussed within the paper.

  8. Supporting conceptual modelling of dynamic systems: A knowledge engineering perspective on qualitative reasoning

    NARCIS (Netherlands)

    Liem, J.

    2013-01-01

    Research has shown that even students educated in science at prestigious universities have misconceptions about the systems underlying climate change, sustainability and government spending. Interactive conceptual modelling and simulation tools, which are based on Artificial Intelligence techniques,

  9. Method of modelization assistance with bond graphs and application to qualitative diagnosis of physical systems

    International Nuclear Information System (INIS)

    Lucas, B.

    1994-05-01

    After having recalled the usual diagnosis techniques (failure index, decision tree) and those based on an artificial intelligence approach, the author reports a research aimed at exploring the knowledge and model generation technique. He focuses on the design of an aid to model generation tool and aid-to-diagnosis tool. The bond graph technique is shown to be adapted to the aid to model generation, and is then adapted to the aid to diagnosis. The developed tool is applied to three projects: DIADEME (a diagnosis system based on physical model), the improvement of the SEXTANT diagnosis system (an expert system for transient analysis), and the investigation on an Ariane 5 launcher component. Notably, the author uses the Reiter and Greiner algorithm

  10. Conceptual model for dietary behaviour change at household level: a 'best-fit' qualitative study using primary data.

    Science.gov (United States)

    Daivadanam, Meena; Wahlström, Rolf; Ravindran, T K Sundari; Thankappan, K R; Ramanathan, Mala

    2014-06-09

    Interventions having a strong theoretical basis are more efficacious, providing a strong argument for incorporating theory into intervention planning. The objective of this study was to develop a conceptual model to facilitate the planning of dietary intervention strategies at the household level in rural Kerala. Three focus group discussions and 17 individual interviews were conducted among men and women, aged between 23 and 75 years. An interview guide facilitated the process to understand: 1) feasibility and acceptability of a proposed dietary behaviour change intervention; 2) beliefs about foods, particularly fruits and vegetables; 3) decision-making in households with reference to food choices and access; and 4) to gain insights into the kind of intervention strategies that may be practical at community and household level. The data were analysed using a modified form of qualitative framework analysis, which combined both deductive and inductive reasoning. A priori themes were identified from relevant behaviour change theories using construct definitions, and used to index the meaning units identified from the primary qualitative data. In addition, new themes emerging from the data were included. The associations between the themes were mapped into four main factors and its components, which contributed to construction of the conceptual model. Thirteen of the a priori themes from three behaviour change theories (Trans-theoretical model, Health Belief model and Theory of Planned Behaviour) were confirmed or slightly modified, while four new themes emerged from the data. The conceptual model had four main factors and its components: impact factors (decisional balance, risk perception, attitude); change processes (action-oriented, cognitive); background factors (personal modifiers, societal norms); and overarching factors (accessibility, perceived needs and preferences), built around a three-stage change spiral (pre-contemplation, intention, action). Decisional

  11. Experiences of role model instructors and nursing students about facilitator factors of role-modelpan>ing process: A qualitative research.

    Science.gov (United States)

    Nouri, Jamileh Mokhtari; Ebadi, Abbas; Alhani, Fatemeh; Rejeh, Nahid

    2014-05-01

    One of the key strategies in students' learning is the influence of models on them. Understanding the factors affecting the implementation of role-modelpan>ing process in education will help to make greater use of this training strategy. This study aimed to understand the experiences of role model instructors and nursing students about the facilitator factors in the role-modelpan>ing process. This qualitative study was carried out by using thematic analysis method and purposeful sampling. Data were collected until saturation by using three focus group discussions (n = 20) and two individual interviews with nursing instructors, as well as six semi-structured face-to-face interviews with role model instructors from five nursing faculties of Tehran universities in 2011. Six themes, "effort for humanistic and professional growth of students," "individual and managerial empowerment of instructor," "instructor and student's modeling," "motivation and effort of student," "strategies governing the education system," and "appropriate facilities and equipment," were extracted as the facilitating factors. For development of role-modelpan>ing process in nursing education, paying attention to personal and environmental factors, especially effort for professional and humanistic growth of nursing students is necessary.

  12. The Economics of Reproducibility in Preclinical Research.

    Directory of Open Access Journals (Sweden)

    Leonard P Freedman

    2015-06-01

    Full Text Available Low reproducibility rates within life science research undermine cumulative knowledge production and contribute to both delays and costs of therapeutic drug development. An analysis of past studies indicates that the cumulative (total prevalence of irreproducible preclinical research exceeds 50%, resulting in approximately US$28,000,000,000 (US$28B/year spent on preclinical research that is not reproducible-in the United States alone. We outline a framework for solutions and a plan for long-term improvements in reproducibility rates that will help to accelerate the discovery of life-saving therapies and cures.

  13. Learning Reproducibility with a Yearly Networking Contest

    KAUST Repository

    Canini, Marco

    2017-08-10

    Better reproducibility of networking research results is currently a major goal that the academic community is striving towards. This position paper makes the case that improving the extent and pervasiveness of reproducible research can be greatly fostered by organizing a yearly international contest. We argue that holding a contest undertaken by a plurality of students will have benefits that are two-fold. First, it will promote hands-on learning of skills that are helpful in producing artifacts at the replicable-research level. Second, it will advance the best practices regarding environments, testbeds, and tools that will aid the tasks of reproducibility evaluation committees by and large.

  14. Thou Shalt Be Reproducible! A Technology Perspective

    Directory of Open Access Journals (Sweden)

    Patrick Mair

    2016-07-01

    Full Text Available This article elaborates on reproducibility in psychology from a technological viewpoint. Modernopen source computational environments are shown and explained that foster reproducibilitythroughout the whole research life cycle, and to which emerging psychology researchers shouldbe sensitized, are shown and explained. First, data archiving platforms that make datasets publiclyavailable are presented. Second, R is advocated as the data-analytic lingua franca in psychologyfor achieving reproducible statistical analysis. Third, dynamic report generation environments forwriting reproducible manuscripts that integrate text, data analysis, and statistical outputs such asfigures and tables in a single document are described. Supplementary materials are provided inorder to get the reader started with these technologies.

  15. Qualitative analysis of a stochastic epidemic model with specific functional response and temporary immunity

    Science.gov (United States)

    Hattaf, Khalid; Mahrouf, Marouane; Adnani, Jihad; Yousfi, Noura

    2018-01-01

    In this paper, we propose a stochastic delayed epidemic model with specific functional response. The time delay represents temporary immunity period, i.e., time from recovery to becoming susceptible again. We first show that the proposed model is mathematically and biologically well-posed. Moreover, the extinction of the disease and the persistence in the mean are established in the terms of a threshold value R0S which is smaller than the basic reproduction number R0 of the corresponding deterministic system.

  16. Qualitative properties and hopf bifurcation in haematopoietic disease model with chemotherapy

    Directory of Open Access Journals (Sweden)

    Yafia R.

    2014-01-01

    Full Text Available In this paper, we consider a model describing the dynamics of Hematopoietic Stem Cells (HSC disease with chemotherapy. The model is given by a system of three ordinary differential equations with discrete delay. Its dynamics are studied in term of local stability of the possible steady states for the case without drug intervention term. We prove the existence of periodic oscillations for each case when the delay passes trough a critical values. In the end, we illustrate our results by some numerical simulations.

  17. Family Adaptation to Stroke: A Metasynthesis of Qualitative Research based on Double ABCX Model

    Directory of Open Access Journals (Sweden)

    Ali Hesamzadeh, RN, PhD Student of Nursing

    2015-09-01

    Conclusions: The results of the study are in conformity with the tenets of the Double ABCX Model. Family adaptation is a dynamic process and the present study findings provide rich information on proper assessment and intervention to the practitioners working with families of stroke survivors.

  18. Qualitative and quantitative analyses of the echolocation strategies of bats on the basis of mathematical modelling and laboratory experiments.

    Science.gov (United States)

    Aihara, Ikkyu; Fujioka, Emyo; Hiryu, Shizuko

    2013-01-01

    Prey pursuit by an echolocating bat was studied theoretically and experimentally. First, a mathematical model was proposed to describe the flight dynamics of a bat and a single prey. In this model, the flight angle of the bat was affected by [Formula: see text] angles related to the flight path of the single moving prey, that is, the angle from the bat to the prey and the flight angle of the prey. Numerical simulation showed that the success rate of prey capture was high, when the bat mainly used the angle to the prey to minimize the distance to the prey, and also used the flight angle of the prey to minimize the difference in flight directions of itself and the prey. Second, parameters in the model were estimated according to experimental data obtained from video recordings taken while a Japanese horseshoe bat (Rhinolphus derrumequinum nippon) pursued a moving moth (Goniocraspidum pryeri) in a flight chamber. One of the estimated parameter values, which represents the ratio in the use of the [Formula: see text] angles, was consistent with the optimal value of the numerical simulation. This agreement between the numerical simulation and parameter estimation suggests that a bat chooses an effective flight path for successful prey capture by using the [Formula: see text] angles. Finally, the mathematical model was extended to include a bat and [Formula: see text] prey. Parameter estimation of the extended model based on laboratory experiments revealed the existence of bat's dynamical attention towards [Formula: see text] prey, that is, simultaneous pursuit of [Formula: see text] prey and selective pursuit of respective prey. Thus, our mathematical model contributes not only to quantitative analysis of effective foraging, but also to qualitative evaluation of a bat's dynamical flight strategy during multiple prey pursuit.

  19. Qualitative and quantitative analyses of the echolocation strategies of bats on the basis of mathematical modelling and laboratory experiments.

    Directory of Open Access Journals (Sweden)

    Ikkyu Aihara

    Full Text Available Prey pursuit by an echolocating bat was studied theoretically and experimentally. First, a mathematical model was proposed to describe the flight dynamics of a bat and a single prey. In this model, the flight angle of the bat was affected by [Formula: see text] angles related to the flight path of the single moving prey, that is, the angle from the bat to the prey and the flight angle of the prey. Numerical simulation showed that the success rate of prey capture was high, when the bat mainly used the angle to the prey to minimize the distance to the prey, and also used the flight angle of the prey to minimize the difference in flight directions of itself and the prey. Second, parameters in the model were estimated according to experimental data obtained from video recordings taken while a Japanese horseshoe bat (Rhinolphus derrumequinum nippon pursued a moving moth (Goniocraspidum pryeri in a flight chamber. One of the estimated parameter values, which represents the ratio in the use of the [Formula: see text] angles, was consistent with the optimal value of the numerical simulation. This agreement between the numerical simulation and parameter estimation suggests that a bat chooses an effective flight path for successful prey capture by using the [Formula: see text] angles. Finally, the mathematical model was extended to include a bat and [Formula: see text] prey. Parameter estimation of the extended model based on laboratory experiments revealed the existence of bat's dynamical attention towards [Formula: see text] prey, that is, simultaneous pursuit of [Formula: see text] prey and selective pursuit of respective prey. Thus, our mathematical model contributes not only to quantitative analysis of effective foraging, but also to qualitative evaluation of a bat's dynamical flight strategy during multiple prey pursuit.

  20. Transparent, reproducible and reusable research in pharmacoepidemiology

    NARCIS (Netherlands)

    Gardarsdottir, Helga; Sauer, Brian C.; Liang, Huifang; Ryan, Patrick; Klungel, Olaf; Reynolds, Robert

    2012-01-01

    Background: Epidemiological research has been criticized as being unreliable. Scientific evidence is strengthened when the study procedures of important findings are transparent, open for review, and easily reproduced by different investigators and in various settings. Studies often have common

  1. Thou Shalt Be Reproducible! A Technology Perspective

    Science.gov (United States)

    Mair, Patrick

    2016-01-01

    This article elaborates on reproducibility in psychology from a technological viewpoint. Modern open source computational environments are shown and explained that foster reproducibility throughout the whole research life cycle, and to which emerging psychology researchers should be sensitized, are shown and explained. First, data archiving platforms that make datasets publicly available are presented. Second, R is advocated as the data-analytic lingua franca in psychology for achieving reproducible statistical analysis. Third, dynamic report generation environments for writing reproducible manuscripts that integrate text, data analysis, and statistical outputs such as figures and tables in a single document are described. Supplementary materials are provided in order to get the reader started with these technologies. PMID:27471486

  2. Archiving Reproducible Research with R and Dataverse

    DEFF Research Database (Denmark)

    Leeper, Thomas

    2014-01-01

    Reproducible research and data archiving are increasingly important issues in research involving statistical analyses of quantitative data. This article introduces the dvn package, which allows R users to publicly archive datasets, analysis files, codebooks, and associated metadata in Dataverse...

  3. Using satellite imagery for qualitative evaluation of plume transport in modeling the effects of the Kuwait oil fire smoke plumes

    International Nuclear Information System (INIS)

    Bass, A.; Janota, P.

    1992-01-01

    To forecast the behavior of the Kuwait oil fire smoke plumes and their possible acute or chronic health effects over the Arabian Gulf region, TASC created a comprehensive health and environmental impacts modeling system. A specially-adapted Lagrangian puff transport model was used to create (a) short-term (multiday) forecasts of plume transport and ground-level concentrations of soot and SO 2 ; and (b) long-term (seasonal and longer) estimates of average surface concentrations and depositions. EPA-approved algorithms were used to transform exposures to SO 2 and soot (as PAH/BaP) into morbidity, mortality and crop damage risks. Absent any ground truth, satellite imagery from the NOAA Polar Orbiter and the ESA Geostationary Meteosat offered the only opportunity for timely qualitative evaluation of the long-range plume transport and diffusion predictions. This paper shows the use of actual satellite images (including animated loops of hourly Meteosat images) to evaluate plume forecasts in near-real-time, and to sanity-check the meso- and long-range plume transport projections for the long-term estimates. Example modeled concentrations, depositions and health effects are shown

  4. Qualitative modelling of gold mine impacts on Lihir Island's socioeconomic system and reef-edge fish community.

    Science.gov (United States)

    Dambacher, Jeffrey M; Brewer, David T; Dennis, Darren M; Macintyre, Martha; Foale, Simon

    2007-01-15

    Inhabitants of Lihir Island, Papua New Guinea, have traditionally relied on reef fishing and rotational farming of slash-burn forest plots for a subsistence diet. However, a new gold mine has introduced a cash economy to the island's socioeconomic system and impacted the fringing coral reef through sedimentation from the near-shore dumping of mine wastes. Studies of the Lihirian people have documented changes in population size, local customs, health, education, and land use; studies of the reef have documented impacts to fish populations in mine affected sites. Indirect effects from these impacts are complex and indecipherable when viewed only from isolated studies. Here, we use qualitative modelling to synthesize the social and biological research programs in order to understand the interaction of the human and ecological systems. Initial modelling results appear to be consistent with differences in fish and macroalgae populations in sites with and without coral degradation due to sedimentation. A greater cash flow from mine expansion is predicted to increase the human population, the intensity of the artisanal fishery, and the rate of sewage production and land clearing. Modelling results are being used to guide ongoing research projects, such as monitoring fish populations and artisanal catch and patterns and intensity of land clearing.

  5. Describing team development within a novel GP-led urgent care centre model : a qualitative study.

    OpenAIRE

    Morton, Sarah; Ignatowicz, Agnieszka; Gnani, Shamini; Majeed, Azeem; Greenfield, Geva

    2016-01-01

    Objective:\\ud Urgent care centres (UCCs) co-located within an emergency department were developed to reduce the numbers of inappropriate emergency department admissions. Since then various UCC models have developed, including a novel general practitioner (GP)-led UCC that incorporates both GPs and emergency nurse practitioners (ENPs). Traditionally these two groups do not work alongside each other within an emergency setting. Although good teamwork is crucial to better patient outcomes, there...

  6. Diffusion of a collaborative care model in primary care: a longitudinal qualitative study.

    Science.gov (United States)

    Vedel, Isabelle; Ghadi, Veronique; De Stampa, Matthieu; Routelous, Christelle; Bergman, Howard; Ankri, Joel; Lapointe, Liette

    2013-01-04

    Although collaborative team models (CTM) improve care processes and health outcomes, their diffusion poses challenges related to difficulties in securing their adoption by primary care clinicians (PCPs). The objectives of this study are to understand: (1) how the perceived characteristics of a CTM influenced clinicians' decision to adopt -or not- the model; and (2) the model's diffusion process. We conducted a longitudinal case study based on the Diffusion of Innovations Theory. First, diffusion curves were developed for all 175 PCPs and 59 nurses practicing in one borough of Paris. Second, semi-structured interviews were conducted with a representative sample of 40 PCPs and 15 nurses to better understand the implementation dynamics. Diffusion curves showed that 3.5 years after the start of the implementation, 100% of nurses and over 80% of PCPs had adopted the CTM. The dynamics of the CTM's diffusion were different between the PCPs and the nurses. The slopes of the two curves are also distinctly different. Among the nurses, the critical mass of adopters was attained faster, since they adopted the CTM earlier and more quickly than the PCPs. Results of the semi-structured interviews showed that these differences in diffusion dynamics were mostly founded in differences between the PCPs' and the nurses' perceptions of the CTM's compatibility with norms, values and practices and its relative advantage (impact on patient management and work practices). Opinion leaders played a key role in the diffusion of the CTM among PCPs. CTM diffusion is a social phenomenon that requires a major commitment by clinicians and a willingness to take risks; the role of opinion leaders is key. Paying attention to the notion of a critical mass of adopters is essential to developing implementation strategies that will accelerate the adoption process by clinicians.

  7. A qualitative readiness-requirements assessment model for enterprise big-data infrastructure investment

    Science.gov (United States)

    Olama, Mohammed M.; McNair, Allen W.; Sukumar, Sreenivas R.; Nutaro, James J.

    2014-05-01

    In the last three decades, there has been an exponential growth in the area of information technology providing the information processing needs of data-driven businesses in government, science, and private industry in the form of capturing, staging, integrating, conveying, analyzing, and transferring data that will help knowledge workers and decision makers make sound business decisions. Data integration across enterprise warehouses is one of the most challenging steps in the big data analytics strategy. Several levels of data integration have been identified across enterprise warehouses: data accessibility, common data platform, and consolidated data model. Each level of integration has its own set of complexities that requires a certain amount of time, budget, and resources to implement. Such levels of integration are designed to address the technical challenges inherent in consolidating the disparate data sources. In this paper, we present a methodology based on industry best practices to measure the readiness of an organization and its data sets against the different levels of data integration. We introduce a new Integration Level Model (ILM) tool, which is used for quantifying an organization and data system's readiness to share data at a certain level of data integration. It is based largely on the established and accepted framework provided in the Data Management Association (DAMADMBOK). It comprises several key data management functions and supporting activities, together with several environmental elements that describe and apply to each function. The proposed model scores the maturity of a system's data governance processes and provides a pragmatic methodology for evaluating integration risks. The higher the computed scores, the better managed the source data system and the greater the likelihood that the data system can be brought in at a higher level of integration.

  8. Diffusion of a collaborative care model in primary care: a longitudinal qualitative study

    Directory of Open Access Journals (Sweden)

    Vedel Isabelle

    2013-01-01

    Full Text Available Background Although collaborative team models (CTM improve care processes and health outcomes, their diffusion poses challenges related to difficulties in securing their adoption by primary care clinicians (PCPs. The objectives of this study are to understand: (1 how the perceived characteristics of a CTM influenced clinicians' decision to adopt -or not- the model; and (2 the model's diffusion process. Methods We conducted a longitudinal case study based on the Diffusion of Innovations Theory. First, diffusion curves were developed for all 175 PCPs and 59 nurses practicing in one borough of Paris. Second, semi-structured interviews were conducted with a representative sample of 40 PCPs and 15 nurses to better understand the implementation dynamics. Results Diffusion curves showed that 3.5 years after the start of the implementation, 100% of nurses and over 80% of PCPs had adopted the CTM. The dynamics of the CTM's diffusion were different between the PCPs and the nurses. The slopes of the two curves are also distinctly different. Among the nurses, the critical mass of adopters was attained faster, since they adopted the CTM earlier and more quickly than the PCPs. Results of the semi-structured interviews showed that these differences in diffusion dynamics were mostly founded in differences between the PCPs' and the nurses' perceptions of the CTM's compatibility with norms, values and practices and its relative advantage (impact on patient management and work practices. Opinion leaders played a key role in the diffusion of the CTM among PCPs. Conclusion CTM diffusion is a social phenomenon that requires a major commitment by clinicians and a willingness to take risks; the role of opinion leaders is key. Paying attention to the notion of a critical mass of adopters is essential to developing implementation strategies that will accelerate the adoption process by clinicians.

  9. Describing team development within a novel GP-led urgent care centre model: a qualitative study.

    Science.gov (United States)

    Morton, Sarah; Ignatowicz, Agnieszka; Gnani, Shamini; Majeed, Azeem; Greenfield, Geva

    2016-06-23

    Urgent care centres (UCCs) co-located within an emergency department were developed to reduce the numbers of inappropriate emergency department admissions. Since then various UCC models have developed, including a novel general practitioner (GP)-led UCC that incorporates both GPs and emergency nurse practitioners (ENPs). Traditionally these two groups do not work alongside each other within an emergency setting. Although good teamwork is crucial to better patient outcomes, there is little within the literature about the development of a team consisting of different healthcare professionals in a novel healthcare setting. Our aim was therefore to describe staff members' perspectives of team development within the GP-led UCC model. Open-ended semistructured interviews, analysed using thematic content analysis. GP-led urgent care centres in two academic teaching hospitals in London. 15 UCC staff members including six GPs, four ENPs, two receptionists and three managers. Overall participants were positive about the interprofessional team that had developed and recognised that this process had taken time. Hierarchy within the UCC setting has diminished with time, although some residual hierarchical beliefs do appear to remain. Staff appreciated interdisciplinary collaboration was likely to improve patient care. Eight key facilitating factors for the team were identified: appointment of leaders, perception of fair workload, education on roles/skill sets and development of these, shared professional understanding, interdisciplinary working, ED collaboration, clinical guidelines and social interactions. A strong interprofessional team has evolved within the GP-led UCCs over time, breaking down traditional professional divides. Future implementation of UCC models should pro-actively incorporate the eight facilitating factors identified from the outset, to enable effective teams to develop more quickly. Published by the BMJ Publishing Group Limited. For permission to use

  10. Reproducing Monocultural Education: Ethnic Majority Staff's Discursive Constructions of Monocultural School Practices

    Science.gov (United States)

    Mampaey, Jelle; Zanoni, Patrizia

    2016-01-01

    This paper investigates the role of ethnic majority staff in the perpetuation of monocultural education that excludes non-western, ethnic minority cultures and reproduces institutional racism in schools. Based on qualitative data collected through semi-structured interviews in four ethnically diverse schools in the Flemish educational system, we…

  11. Qualitative analysis of an integro-differential equation model of periodic chemotherapy

    KAUST Repository

    Jain, Harsh Vardhan

    2012-12-01

    An existing model of tumor growth that accounts for cell cycle arrest and cell death induced by chemotherapy is extended to simulate the response to treatment of a tumor growing in vivo. The tumor is assumed to undergo logistic growth in the absence of therapy, and treatment is administered periodically rather than continuously. Necessary and sufficient conditions for the global stability of the cancer-free equilibrium are derived and conditions under which the system evolves to periodic solutions are determined. © 2012 Elsevier Ltd. All rights reserved.

  12. Modeling bistable cell-fate choices in the Drosophila eye: qualitative and quantitative perspectives

    Science.gov (United States)

    Graham, Thomas G. W.; Tabei, S. M. Ali; Dinner, Aaron R.; Rebay, Ilaria

    2010-01-01

    A major goal of developmental biology is to understand the molecular mechanisms whereby genetic signaling networks establish and maintain distinct cell types within multicellular organisms. Here, we review cell-fate decisions in the developing eye of Drosophila melanogaster and the experimental results that have revealed the topology of the underlying signaling circuitries. We then propose that switch-like network motifs based on positive feedback play a central role in cell-fate choice, and discuss how mathematical modeling can be used to understand and predict the bistable or multistable behavior of such networks. PMID:20570936

  13. Data Science Innovations That Streamline Development, Documentation, Reproducibility, and Dissemination of Models in Computational Thermodynamics: An Application of Image Processing Techniques for Rapid Computation, Parameterization and Modeling of Phase Diagrams

    Science.gov (United States)

    Ghiorso, M. S.

    2014-12-01

    Computational thermodynamics (CT) represents a collection of numerical techniques that are used to calculate quantitative results from thermodynamic theory. In the Earth sciences, CT is most often applied to estimate the equilibrium properties of solutions, to calculate phase equilibria from models of the thermodynamic properties of materials, and to approximate irreversible reaction pathways by modeling these as a series of local equilibrium steps. The thermodynamic models that underlie CT calculations relate the energy of a phase to temperature, pressure and composition. These relationships are not intuitive and they are seldom well constrained by experimental data; often, intuition must be applied to generate a robust model that satisfies the expectations of use. As a consequence of this situation, the models and databases the support CT applications in geochemistry and petrology are tedious to maintain as new data and observations arise. What is required to make the process more streamlined and responsive is a computational framework that permits the rapid generation of observable outcomes from the underlying data/model collections, and importantly, the ability to update and re-parameterize the constitutive models through direct manipulation of those outcomes. CT procedures that take models/data to the experiential reference frame of phase equilibria involve function minimization, gradient evaluation, the calculation of implicit lines, curves and surfaces, contour extraction, and other related geometrical measures. All these procedures are the mainstay of image processing analysis. Since the commercial escalation of video game technology, open source image processing libraries have emerged (e.g., VTK) that permit real time manipulation and analysis of images. These tools find immediate application to CT calculations of phase equilibria by permitting rapid calculation and real time feedback between model outcome and the underlying model parameters.

  14. Stepwise sensitivity analysis from qualitative to quantitative: Application to the terrestrial hydrological modeling of a Conjunctive Surface-Subsurface Process (CSSP) land surface model

    Science.gov (United States)

    Gan, Yanjun; Liang, Xin-Zhong; Duan, Qingyun; Choi, Hyun Il; Dai, Yongjiu; Wu, Huan

    2015-06-01

    An uncertainty quantification framework was employed to examine the sensitivities of 24 model parameters from a newly developed Conjunctive Surface-Subsurface Process (CSSP) land surface model (LSM). The sensitivity analysis (SA) was performed over 18 representative watersheds in the contiguous United States to examine the influence of model parameters in the simulation of terrestrial hydrological processes. Two normalized metrics, relative bias (RB) and Nash-Sutcliffe efficiency (NSE), were adopted to assess the fit between simulated and observed streamflow discharge (SD) and evapotranspiration (ET) for a 14 year period. SA was conducted using a multiobjective two-stage approach, in which the first stage was a qualitative SA using the Latin Hypercube-based One-At-a-Time (LH-OAT) screening, and the second stage was a quantitative SA using the Multivariate Adaptive Regression Splines (MARS)-based Sobol' sensitivity indices. This approach combines the merits of qualitative and quantitative global SA methods, and is effective and efficient for understanding and simplifying large, complex system models. Ten of the 24 parameters were identified as important across different watersheds. The contribution of each parameter to the total response variance was then quantified by Sobol' sensitivity indices. Generally, parameter interactions contribute the most to the response variance of the CSSP, and only 5 out of 24 parameters dominate model behavior. Four photosynthetic and respiratory parameters are shown to be influential to ET, whereas reference depth for saturated hydraulic conductivity is the most influential parameter for SD in most watersheds. Parameter sensitivity patterns mainly depend on hydroclimatic regime, as well as vegetation type and soil texture. This article was corrected on 26 JUN 2015. See the end of the full text for details.

  15. Mathematical-statistical models and qualitative theories for economic and social sciences

    CERN Document Server

    Maturo, Fabrizio; Kacprzyk, Janusz

    2017-01-01

    This book presents a broad spectrum of problems related to statistics, mathematics, teaching, social science, and economics as well as a range of tools and techniques that can be used to solve these problems. It is the result of a scientific collaboration between experts in the field of economic and social systems from the University of Defence in Brno (Czech Republic), G. d’Annunzio University of Chieti-Pescara (Italy), Pablo de Olavid eUniversity of Sevilla (Spain), and Ovidius University in Constanţa, (Romania). The studies included were selected using a peer-review process and reflect heterogeneity and complexity of economic and social phenomena. They and present interesting empirical research from around the globe and from several research fields, such as statistics, decision making, mathematics, complexity, psychology, sociology and economics. The volume is divided into two parts. The first part, “Recent trends in mathematical and statistical models for economic and social sciences”, collects pap...

  16. Mathematical Modeling of Hidden Intimate Partner Violence in Spain: A Quantitative and Qualitative Approach

    Directory of Open Access Journals (Sweden)

    E. De la Poza

    2016-01-01

    Full Text Available The fact that women are abused by their male partner is something that happens worldwide in the 21st century. In numerous cases, abuse only becomes publicly known when a fatal event occurs and is beyond any possible remedy, that is, when men murder their female partner. Since 2003, 793 (September 4, 2015 women have been assassinated by their significant other or excouple in Spain. Only 7.2% of murdered women had reported their fear and previous intimate partner violence (IPV to the police. Even when the number of female victims is comparable to the number of victims by terrorism, the Government has not assigned an equal amount of resources to diminish the magnitude of this hidden social problem. In this paper, a mathematical epidemiological model to forecast intimate partner violence in Spain is constructed. Both psychological and physical aggressor subpopulations are predicted and simulated. The model’s robustness versus uncertain parameters is studied by a sensitivity analysis.

  17. Scaling Qualitative Probability

    OpenAIRE

    Burgin, Mark

    2017-01-01

    There are different approaches to qualitative probability, which includes subjective probability. We developed a representation of qualitative probability based on relational systems, which allows modeling uncertainty by probability structures and is more coherent than existing approaches. This setting makes it possible proving that any comparative probability is induced by some probability structure (Theorem 2.1), that classical probability is a probability structure (Theorem 2.2) and that i...

  18. Applying the Information-Motivation-Behavioral Skills Model in Medication Adherence Among Thai Youth Living with HIV: A Qualitative Study

    Science.gov (United States)

    Naar-King, Sylvie; Kaljee, Linda M.; Panthong, Apirudee; Koken, Juline A.; Bunupuradah, Torsak; Parsons, Jeffrey T.

    2010-01-01

    Abstract With disproportionately higher rates of HIV/AIDS among youth and increasing access to antiretroviral therapy (ART) in Thailand, there is a growing urgency in understanding the challenges to medication adherence confronting this population and in developing theory-based interventions to address these challenges. One potentially relevant model, the information-motivation-behavioral skills (IMB) model of adherence, was developed in Western settings characterized by a more individualistic culture in contrast to the more collectivistic culture of Thailand. We explored the application and adaptability of IMB on ART adherence among HIV-positive Thai youth through the analysis of qualitative data from a pilot motivational interviewing study. Twenty-two interview sessions from 10 HIV-positive Thai youth (17–24 years) were analyzed; 6 youth were on ART. Data support the utility of IMB as a potential framework for understanding ART adherence in this population. However, data indicate a consideration to expand the motivation construct of IMB to incorporate youths' perceived familial and social responsibilities and the need to adhere to medications for short- and long-term well-being of self, family, and society in a context of Buddhist values. These modifications to IMB could be relevant in other cultural settings with more collectivistic worldviews. PMID:21091238

  19. Global energy supply the day before yesterday, the day after tomorrow, today, tomorrow - a qualitative modeling approach

    International Nuclear Information System (INIS)

    Herrmann, D.

    2004-01-01

    Current developments, and peak world market price levels, of oil, which add to the prices also of natural gas and other energy resources, give rise to the question whether there is any reason to expect fundamental changes and trend reversals in energy prices and on energy markets on a medium to long term basis. Attempts to find answers to such questions about the future can be helped by looking back into the more than three hundred years of global history of the development of modern industrial-sale power supply. Over that period of time, there have always been changes of boundary conditions and reversals of trends, respectively; step by step, by trial and error, a structural change has evolved from the use mainly of renewable energy resources to the primary use of fossil fuels supplemented by nuclear power. A model is presented which is able not only to describe and explain in a consistent and plausible way the global qualitative development of industrial-scale energy supply over the three different development periods, as far as contents go, between 1700 and 2100, but also allows higher resolution to be achieved in terms both of contents and time. The modeling approach is applied to the entire era of energy supply on an industrial scale, and should be seen as a representation of the specific perspective in this approach for further discussion. (orig.)

  20. Applying the information-motivation-behavioral skills model in medication adherence among Thai youth living with HIV: a qualitative study.

    Science.gov (United States)

    Rongkavilit, Chokechai; Naar-King, Sylvie; Kaljee, Linda M; Panthong, Apirudee; Koken, Juline A; Bunupuradah, Torsak; Parsons, Jeffrey T

    2010-12-01

    With disproportionately higher rates of HIV/AIDS among youth and increasing access to antiretroviral therapy (ART) in Thailand, there is a growing urgency in understanding the challenges to medication adherence confronting this population and in developing theory-based interventions to address these challenges. One potentially relevant model, the information-motivation-behavioral skills (IMB) model of adherence, was developed in Western settings characterized by a more individualistic culture in contrast to the more collectivistic culture of Thailand. We explored the application and adaptability of IMB on ART adherence among HIV-positive Thai youth through the analysis of qualitative data from a pilot motivational interviewing study. Twenty-two interview sessions from 10 HIV-positive Thai youth (17-24 years) were analyzed; 6 youth were on ART. Data support the utility of IMB as a potential framework for understanding ART adherence in this population. However, data indicate a consideration to expand the motivation construct of IMB to incorporate youths' perceived familial and social responsibilities and the need to adhere to medications for short- and long-term well-being of self, family, and society in a context of Buddhist values. These modifications to IMB could be relevant in other cultural settings with more collectivistic worldviews.

  1. A qualitative model for strategic analysis of organizations. Application and alternative proposal on a study case

    Directory of Open Access Journals (Sweden)

    Santiago Ferro Moreno

    2015-12-01

    Full Text Available The strategic analysis of organizations is based on the internal and external environments, in order to identify positive and negative variables and factors. The interrelation and timing of these strategic forces are essential to create alternative solutions that tend to achieve the organizational objectives.The normative prospective has theorical and methodological foundations to create a desired future and from it, be able to identify impelling and restraining forces that have influence on the particular problematic situation (go from the current situation to a better one in a certain time.The aim of this article is to analyze on a strategic way a real case with a normative-prospective model that considers the temporal dynamics of the factors impact and variables in time allowing to suggest alternative solutions.Semi-structured interviews were performed with all the employees of this case and structured observations and workshops with the commercial and general management.In consequence, with the results, the desired, current and improved situations were built. Additionally, forces were identified classified and appreciated and lastly solutions were suggested. With the proposed prospective method, alternative solutions could be constructed in order to settle temporary organizational objectives. No constraints were found to use the current method in other cases.Keywords: Strategic forces, Normative prospective, Problematic situations, Strategies

  2. The explanatory models and coping strategies for alcohol use disorders: An exploratory qualitative study from India☆

    Science.gov (United States)

    Nadkarni, Abhijit; Dabholkar, Hamid; McCambridge, Jim; Bhat, Bhargav; Kumar, Shuba; Mohanraj, Rani; Murthy, Pratima; Patel, Vikram

    2013-01-01

    Purpose The explanatory models (EM) and coping strategies for mental health problems influence treatment seeking and the subsequent patient journey. The goal of this study was to explore the EMs and coping strategies for alcohol use disorders (AUD). Methods We conducted semi structured interviews with 29 men with AUD and 10 significant others (SO) in two sites in India. Thematic analysis was used to analyse data. Results The former were predominantly married, literate and employed; the latter were predominantly wives, literate and employed. Alcohol consumption and AUDs are seen to be mainly associated with psychosocial stress, with other factors being peer influences, availability of disposable income and drinking for pleasure. They are perceived to result in a range of adverse impacts on social life, family life, personal health and family finances. Various coping strategies were deployed by men with AUD and their significant others, for example avoidance, substitution, distraction, religious activities, support from AA/friends/family, restricting means to buy alcohol and anger management. Reduction/cessation in drinking, improved family relationships, improved emotional/physical wellbeing and better occupational functioning were the most desired treatment outcomes. Conclusion There are considerable similarities, as well as some key differences, observed between the EMs for AUD in India and those reported from other cultures which have implications for the global applicability and contextual adaptations of evidence based interventions for AUD. PMID:24309865

  3. Qualitative and quantitative changes in phospholipids and proteins investigated by spectroscopic techniques in animal depression model

    Science.gov (United States)

    Depciuch, J.; Sowa-Kucma, M.; Nowak, G.; Papp, M.; Gruca, P.; Misztak, P.; Parlinska-Wojtan, M.

    2017-04-01

    Depression becomes nowadays a high mortality civilization disease with one of the major causes being chronic stress. Raman, Fourier Transform Infra Red (FTIR) and Ultraviolet-Visible (UV-vis) spectroscopies were used to determine the changes in the quantity and structure of phospholipids and proteins in the blood serum of rats subjected to chronic mild stress, which is a common animal depression model. Moreover, the efficiency of the imipramine treatment was evaluated. It was found that chronic mild stress not only damages the structure of the phospholipids and proteins, but also decreases their level in the blood serum. A 5 weeks imipramine treatment did increase slightly the quantity of proteins, leaving the damaged phospholipids unchanged. Structural information from phospholipids and proteins was obtained by UV-vis spectroscopy combined with the second derivative of the FTIR spectra. Indeed, the structure of proteins in blood serum of stressed rats was normalized after imipramine therapy, while the impaired structure of phospholipids remained unaffected. These findings strongly suggest that the depression factor, which is chronic mild stress, may induce permanent (irreversible) damages into the phospholipid structure identified as shortened carbon chains. This study shows a possible new application of spectroscopic techniques in the diagnosis and therapy monitoring of depression.

  4. A Critical Review of Qualitative Research Methods in Evaluating Nursing Curriculum Models: Implication for Nursing Education in the Arab World

    Science.gov (United States)

    Devadas, Briliya

    2016-01-01

    Aim: The purpose of this critical literature review was to examine qualitative studies done on innovative nursing curriculums in order to determine which qualitative methods have been most effective in investigating the effectiveness of the curriculum and which would be most appropriate in an Arab Islamic country. Data Sources: At least 25 studies…

  5. MRSA model of learning and adaptation: a qualitative study among the general public

    Directory of Open Access Journals (Sweden)

    Rohde Rodney E

    2012-04-01

    Full Text Available Abstract Background More people in the US now die from Methicillin Resistant Staphylococcus aureus (MRSA infections than from HIV/AIDS. Often acquired in healthcare facilities or during healthcare procedures, the extremely high incidence of MRSA infections and the dangerously low levels of literacy regarding antibiotic resistance in the general public are on a collision course. Traditional medical approaches to infection control and the conventional attitude healthcare practitioners adopt toward public education are no longer adequate to avoid this collision. This study helps us understand how people acquire and process new information and then adapt behaviours based on learning. Methods Using constructivist theory, semi-structured face-to-face and phone interviews were conducted to gather pertinent data. This allowed participants to tell their stories so their experiences could deepen our understanding of this crucial health issue. Interview transcripts were analysed using grounded theory and sensitizing concepts. Results Our findings were classified into two main categories, each of which in turn included three subthemes. First, in the category of Learning, we identified how individuals used their Experiences with MRSA, to answer the questions: What was learned? and, How did learning occur? The second category, Adaptation gave us insights into Self-reliance, Reliance on others, and Reflections on the MRSA journey. Conclusions This study underscores the critical importance of educational programs for patients, and improved continuing education for healthcare providers. Five specific results of this study can reduce the vacuum that currently exists between the knowledge and information available to healthcare professionals, and how that information is conveyed to the public. These points include: 1 a common model of MRSA learning and adaptation; 2 the self-directed nature of adult learning; 3 the focus on general MRSA information, care and

  6. Reproducibility of pacing profiles in elite swimmers.

    Science.gov (United States)

    Skorski, Sabrina; Faude, Oliver; Caviezel, Seraina; Meyer, Tim

    2014-03-01

    To analyze the reproducibility of pacing in elite swimmers during competitions and to compare heats and finals within 1 event. Finals and heats of 158 male swimmers (age 22.8 ± 2.9 y) from 29 nations were analyzed in 2 competitions (downloaded from swimrankings.net). Of these, 134 were listed in the world's top 50 in 2010; the remaining 24 were finalists of the Pan Pacific Games or European Championships. The level of both competitions for the analysis had to be at least national championships (7.7 ± 5.4 wk apart). Standard error of measurement expressed as percentage of the subject's mean score (CV) with 90% confidence limits (CL) for each 50-m split time and for total times were calculated. In addition, mixed general modeling was used to determine standard deviations between and within swimmers. CV for total time in finals ranged between 0.8% and 1.3% (CL 0.6-2.2%). Regarding split times, 200-m freestyle showed a consistent pacing over all split times (CV 0.9-1.6%). During butterfly, backstroke, and 400-m freestyle, CVs were low in the first 3 and 7 sections, respectively (CV 0.9-1.7%), with greater variability in the last section (1.9-2.2%). In breaststroke, values were higher in all sections (CV 1.2-2.3%). Within-subject SDs for changes between laps were between 0.9% and 2.6% in all finals. Split-time variability for finals and heats ranged between 0.9% and 2.5% (CL 0.3-4.9%). Pacing profiles are consistent between different competitions. Variability of pacing seems to be a result of the within-subject variation rather than a result of different competitions.

  7. Clinical teaching and learning within a preceptorship model in an acute care hospital in Ireland; a qualitative study.

    Science.gov (United States)

    McSharry, Edel; Lathlean, Judith

    2017-04-01

    A preceptorship model of clinical teaching was introduced to support the new all-graduate nurse education programme in Ireland in 2002. Little is known about how this model impacts upon the pedagogical practices of the preceptor or student learning in clinical practice leading to question what constitutes effective teaching and learning in clinical practice at undergraduate level. This study aimed to explore the clinical teaching and learning within a preceptorship model in an acute care hospital in Ireland and identify when best practice, based on current theoretical professional and educational principles occurred. A qualitative research study of a purposively selected sample of 13 students and 13 preceptors, working together in four clinical areas in one hospital in Ireland. Methods were semi-structured interviews, analysed thematically, complemented by documentary analysis relating to the teaching and assessment of the students. Ethical approval was gained from the hospital's Ethics Committee. Preceptor-student contact time within an empowering student-preceptor learning relationship was the foundation of effective teaching and learning and assessment. Dialoguing and talking through practice enhanced the students' knowledge and understanding, while the ability of the preceptor to ask higher order questions promoted the students' clinical reasoning and problem solving skills. Insufficient time to teach, and an over reliance on students' ability to participate in and contribute to practice with minimal guidance were found to negatively impact students' learning. Concepts such as cognitive apprenticeship, scaffolding and learning in communities of practice can be helpful in understanding the processes entailed in preceptorship. Preceptors need extensive educational preparation and support to ensure they have the pedagogical competencies necessary to provide the cognitive teaching techniques that foster professional performance and clinical reasoning. National

  8. Application of qualitative response models in a relevance study of older adults' health depreciation and medical care demand.

    Science.gov (United States)

    Weng, Shuo-Chun; Chen, Yu-Chi; Chen, Ching-Yu; Cheng, Yuan-Yang; Tang, Yih-Jing; Yang, Shu-Hui; Lin, Jwu-Rong

    2017-04-01

    The effect of health depreciation in older people on medical care demand is not well understood. We tried to assess the medical care demand with length of hospitalization and their impact on profits as a result of health depreciation. All participants who underwent comprehensive geriatric assessment were from a prospective cohort study at a tertiary hospital. A total of 1191 cases between September 2008 to October 2012 were investigated. Three sets of qualitative response models were constructed to estimate the impact of older adults' health depreciation on multidisciplinary geriatric care services. Furthermore, we analyzed the factors affecting the composite end-point of rehospitalization within 14 days, re-admission to the emergency department within 3 days and patient death. Greater health depreciation in elderly patients was positively correlated with greater medical care demand. Three major components were defined as health depreciation: elderly adaptation function, geriatric syndromes and multiple chronic diseases. On admission, the better the basic living functions, the shorter the length of hospitalization (coefficient = -0.35, P < 0.001 in Poisson regression; coefficient = -0.33, P < 0.001 in order choice profit model; coefficient = -0.29, P < 0.001 in binary choice profit model). The major determinants for poor outcome were male sex, middle old age and length of hospitalization. However, factors that correlated with relatively good outcome were functional improvement after medical care services and level of disease education. An optimal allocation system for selection of cases into multidisciplinary geriatric care is required because of limited resources. Outcomes will improve with health promotion and preventive care services. Geriatr Gerontol Int 2017; 17: 645-652. © 2016 Japan Geriatrics Society.

  9. Student midwives' perceptions on the organisation of maternity care and alternative maternity care models in the Netherlands - a qualitative study.

    Science.gov (United States)

    Warmelink, J Catja; de Cock, T Paul; Combee, Yvonne; Rongen, Marloes; Wiegers, Therese A; Hutton, Eileen K

    2017-01-11

    A major change in the organisation of maternity care in the Netherlands is under consideration, going from an echelon system where midwives provide primary care in the community and refer to obstetricians for secondary and tertiary care, to a more integrated maternity care system involving midwives and obstetricians at all care levels. Student midwives are the future maternity care providers and they may be entering into a changing maternity care system, so inclusion of their views in the discussion is relevant. This study aimed to explore student midwives' perceptions on the current organisation of maternity care and alternative maternity care models, including integrated care. This qualitative study was based on the interpretivist/constructivist paradigm, using a grounded theory design. Interviews and focus groups with 18 female final year student midwives of the Midwifery Academy Amsterdam Groningen (AVAG) were held on the basis of a topic list, then later transcribed, coded and analysed. Students felt that inevitably there will be a change in the organisation of maternity care, and they were open to change. Participants indicated that good collaboration between professions, including a shared system of maternity notes and guidelines, and mutual trust and respect were important aspects of any alternative model. The students indicated that client-centered care and the safeguarding of the physiological, normalcy approach to pregnancy and birth should be maintained in any alternative model. Students expressed worries that the role of midwives in intrapartum care could become redundant, and thus they are motivated to take on new roles and competencies, so they can ensure their own role in intrapartum care. Final year student midwives recognise that change in the organisation of maternity care is inevitable and have an open attitude towards changes if they include good collaboration, client-centred care and safeguards for normal physiological birth. The graduating

  10. Enacting the International/Reproducing Eurocentrism

    Directory of Open Access Journals (Sweden)

    Zeynep Gülşah Çapan

    Full Text Available Abstract This article focuses on the way in which Eurocentric conceptualisations of the ‘international’ are reproduced in different geopolitical contexts. Even though the Eurocentrism of International Relations has received growing attention, it has predominantly been concerned with unearthing the Eurocentrism of the ‘centre’, overlooking its varied manifestations in other geopolitical contexts. The article seeks to contribute to discussions about Eurocentrism by examining how different conceptualisations of the international are at work at a particular moment, and how these conceptualisations continue to reproduce Eurocentrism. It will focus on the way in which Eurocentric designations of spatial and temporal hierarchies were reproduced in the context of Turkey through a reading of how the ‘Gezi Park protests’ of 2013 and ‘Turkey’ itself were written into the story of the international.

  11. A Bayesian Perspective on the Reproducibility Project: Psychology

    Science.gov (United States)

    Etz, Alexander; Vandekerckhove, Joachim

    2016-01-01

    We revisit the results of the recent Reproducibility Project: Psychology by the Open Science Collaboration. We compute Bayes factors—a quantity that can be used to express comparative evidence for an hypothesis but also for the null hypothesis—for a large subset (N = 72) of the original papers and their corresponding replication attempts. In our computation, we take into account the likely scenario that publication bias had distorted the originally published results. Overall, 75% of studies gave qualitatively similar results in terms of the amount of evidence provided. However, the evidence was often weak (i.e., Bayes factor psychological literature. We further conclude that traditional sample sizes are insufficient and that a more widespread adoption of Bayesian methods is desirable. PMID:26919473

  12. Highly reproducible polyol synthesis for silver nanocubes

    Science.gov (United States)

    Han, Hye Ji; Yu, Taekyung; Kim, Woo-Sik; Im, Sang Hyuk

    2017-07-01

    We could synthesize the Ag nanocubes highly reproducibly by conducting the polyol synthesis using HCl etchant in dark condition because the photodecomposition/photoreduction of AgCl nanoparticles formed at initial reaction stage were greatly depressed and consequently the selective self-nucleation of Ag single crystals and their selective growth reaction could be promoted. Whereas the reproducibility of the formation of Ag nanocubes were very poor when we synthesize the Ag nanocubes in light condition due to the photoreduction of AgCl to Ag.

  13. Experimental challenges to reproduce seismic fault motion

    Science.gov (United States)

    Shimamoto, T.

    2011-12-01

    This presentation briefly reviews scientific and technical development in the studies of intermediate to high-velocity frictional properties of faults and summarizes remaining technical challenges to reproduce nucleation to growth processes of large earthquakes in laboratory. Nearly 10 high-velocity or low to high-velocity friction apparatuses have been built in the last several years in the world and it has become possible now to produce sub-plate velocity to seismic slip rate in a single machine. Despite spreading of high-velocity friction studies, reproducing seismic fault motion at high P and T conditions to cover the entire seismogenic zone is still a big challenge. Previous studies focused on (1) frictional melting, (2) thermal pressurization, and (3) high-velocity gouge behavior without frictional melting. Frictional melting process was solved as a Stefan problem with very good agreement with experimental results. Thermal pressurization has been solved theoretically based on measured transport properties and has been included successfully in the modeling of earthquake generation. High-velocity gouge experiments in the last several years have revealed that a wide variety of gouges exhibit dramatic weakening at high velocities (e.g., Di Toro et al., 2011, Nature). Most gouge experiments were done under dry conditions partly to separate gouge friction from the involvement of thermal pressurization. However, recent studies demonstrated that dehydration or degassing due to mineral decomposition can occur during seismic fault motion. Those results not only provided a new view of looking at natural fault zones in search of geological evidence of seismic fault motion, but also indicated that thermal pressurization and gouge weakening can occur simultaneously even in initially dry gouge. Thus experiments with controlled pore pressure are needed. I have struggled to make a pressure vessel for wet high-velocity experiments in the last several years. A technical

  14. Application of qualitative reasoning with functional knowledge represented by Multilevel Flow Modeling to diagnosis of accidental situation in nuclear power plant

    International Nuclear Information System (INIS)

    Yoshida, Kazuo; Tanabe, Fumiya; Kawase, Katumi.

    1996-01-01

    It has been proposed to use the Multilevel Flow Modeling (MFM) by M. Lind as a framework for functional knowledge representation for qualitative reasoning in a complex process system such as nuclear power plant. To build a knowledge base with MFM framework makes it possible to represent functional characteristics in different levels of abstraction and aggregation. A pilot inference system based on the qualitative reasoning with MFM has been developed to diagnose a cause of abnormal events in a typical PWR power plant. Some single failure events has been diagnosed with this system to verify the proposed method. In the verification study, some investigation has been also performed to clarify the effects of this knowledge representation in efficiency of reasoning and ambiguity of qualitative reasoning. (author)

  15. Neonatal intensive care nursing curriculum challenges based on context, input, process, and product evaluation model: A qualitative study

    Directory of Open Access Journals (Sweden)

    Mansoureh Ashghali-Farahani

    2018-01-01

    Full Text Available Background: Weakness of curriculum development in nursing education results in lack of professional skills in graduates. This study was done on master's students in nursing to evaluate challenges of neonatal intensive care nursing curriculum based on context, input, process, and product (CIPP evaluation model. Materials and Methods: This study was conducted with qualitative approach, which was completed according to the CIPP evaluation model. The study was conducted from May 2014 to April 2015. The research community included neonatal intensive care nursing master's students, the graduates, faculty members, neonatologists, nurses working in neonatal intensive care unit (NICU, and mothers of infants who were hospitalized in such wards. Purposeful sampling was applied. Results: The data analysis showed that there were two main categories: “inappropriate infrastructure” and “unknown duties,” which influenced the context formation of NICU master's curriculum. The input was formed by five categories, including “biomedical approach,” “incomprehensive curriculum,” “lack of professional NICU nursing mentors,” “inappropriate admission process of NICU students,” and “lack of NICU skill labs.” Three categories were extracted in the process, including “more emphasize on theoretical education,” “the overlap of credits with each other and the inconsistency among the mentors,” and “ineffective assessment.” Finally, five categories were extracted in the product, including “preferring routine work instead of professional job,” “tendency to leave the job,” “clinical incompetency of graduates,” “the conflict between graduates and nursing staff expectations,” and “dissatisfaction of graduates.” Conclusions: Some changes are needed in NICU master's curriculum by considering the nursing experts' comments and evaluating the consequences of such program by them.

  16. Elaboration of the Reciprocal-Engagement Model of Genetic Counseling Practice: a Qualitative Investigation of Goals and Strategies.

    Science.gov (United States)

    Redlinger-Grosse, Krista; Veach, Patricia McCarthy; LeRoy, Bonnie S; Zierhut, Heather

    2017-12-01

    As the genetic counseling field evolves, a comprehensive model of practice is critical. The Reciprocal-Engagement Model (REM) consists of 5 tenets and 17 goals. Lacking in the REM, however, are well-articulated counselor strategies and behaviors. The purpose of the present study was to further elaborate and provide supporting evidence for the REM by identifying and mapping genetic counseling strategies to the REM goals. A secondary, qualitative analysis was conducted on data from two prior studies: 1) focus group results of genetic counseling outcomes (Redlinger-Grosse et al., Journal of Genetic Counseling, 2015); and 2) genetic counselors' examples of successful and unsuccessful genetic counseling sessions (Geiser et al. 2009). Using directed content analysis, 337 unique strategies were extracted from focus group data. A Q-sort of the 337 strategies yielded 15 broader strategy domains that were then mapped to the successful and unsuccessful session examples. Differing prevalence of strategy domains identified in successful sessions versus the prevalence of domains identified as lacking in unsuccessful sessions provide further support for the REM goals. The most prevalent domains for successful sessions were Information Giving and Use Psychosocial Skills and Strategies; and for unsuccessful sessions, Information Giving and Establish Working Alliance. Identified strategies support the REM's reciprocal nature, especially with regard to addressing patients' informational and psychosocial needs. Patients' contributions to success (or lack thereof) of sessions was also noted, supporting a REM tenet that individual characteristics and the counselor-patient relationship are central to processes and outcomes. The elaborated REM could be used as a framework for certain graduate curricular objectives, and REM components could also inform process and outcomes research studies to document and further characterize genetic counselor strategies.

  17. Qualitative modeling identifies IL-11 as a novel regulator in maintaining self-renewal in human pluripotent stem cells

    Directory of Open Access Journals (Sweden)

    Hedi ePeterson

    2013-10-01

    Full Text Available Pluripotency in human embryonic stem cells (hESCs and induced pluripotent stem cells (iPSCs is regulated by three transcription factors - OCT3/4, SOX2 and NANOG. To fully exploit the therapeutic potential of these cells it is essential to have a good mechanistic understanding of the maintenance of self-renewal and pluripotency. In this study, we demonstrate a powerful systems biology approach in which we first expand literature-based network encompassing the core regulators of pluripotency by assessing the behaviour of genes targeted by perturbation experiments. We focused our attention on highly regulated genes encoding cell surface and secreted proteins as these can be more easily manipulated by the use of inhibitors or recombinant proteins. Qualitative modeling based on combining boolean networks and in silico perturbation experiments were employed to identify novel pluripotency-regulating genes. We validated Interleukin-11 (IL-11 and demonstrate that this cytokine is a novel pluripotency-associated factor capable of supporting self-renewal in the absence of exogenously added bFGF in culture. To date, the various protocols for hESCs maintenance require supplementation with bFGF to activate the Activin/Nodal branch of the TGFβ signaling pathway. Additional evidence supporting our findings is that IL-11 belongs to the same protein family as LIF, which is known to be necessary for maintaining pluripotency in mouse but not in human ESCs. These cytokines operate through the same gp130 receptor which interacts with Janus kinases. Our finding might explain why mESCs are in a more naïve cell state compared to hESCs and how to convert primed hESCs back to the naïve state. Taken together, our integrative modeling approach has identified novel genes as putative candidates to be incorporated into the expansion of the current gene regulatory network responsible for inducing and maintaining pluripotency.

  18. Modeling Stop-and-Go Waves in Pedestrian Dynamics

    OpenAIRE

    Portz, Andrea; Seyfried, Armin

    2010-01-01

    Several spatially continuous pedestrian dynamics models have been validated against empirical data. We try to reproduce the experimental fundamental diagram (velocity versus density) with simulations. In addition to this quantitative criterion, we tried to reproduce stop-and-go waves as a qualitative criterion. Stop-and-go waves are a characteristic phenomenon for the single file movement. Only one of three investigated models satisfies both criteria.

  19. Assessing the effect of quantitative and qualitative predictors on gastric cancer individuals survival using hierarchical artificial neural network models.

    Science.gov (United States)

    Amiri, Zohreh; Mohammad, Kazem; Mahmoudi, Mahmood; Parsaeian, Mahbubeh; Zeraati, Hojjat

    2013-01-01

    There are numerous unanswered questions in the application of artificial neural network models for analysis of survival data. In most studies, independent variables have been studied as qualitative dichotomous variables, and results of using discrete and continuous quantitative, ordinal, or multinomial categorical predictive variables in these models are not well understood in comparison to conventional models. This study was designed and conducted to examine the application of these models in order to determine the survival of gastric cancer patients, in comparison to the Cox proportional hazards model. We studied the postoperative survival of 330 gastric cancer patients who suffered surgery at a surgical unit of the Iran Cancer Institute over a five-year period. Covariates of age, gender, history of substance abuse, cancer site, type of pathology, presence of metastasis, stage, and number of complementary treatments were entered in the models, and survival probabilities were calculated at 6, 12, 18, 24, 36, 48, and 60 months using the Cox proportional hazards and neural network models. We estimated coefficients of the Cox model and the weights in the neural network (with 3, 5, and 7 nodes in the hidden layer) in the training group, and used them to derive predictions in the study group. Predictions with these two methods were compared with those of the Kaplan-Meier product limit estimator as the gold standard. Comparisons were performed with the Friedman and Kruskal-Wallis tests. Survival probabilities at different times were determined using the Cox proportional hazards and a neural network with three nodes in the hidden layer; the ratios of standard errors with these two methods to the Kaplan-Meier method were 1.1593 and 1.0071, respectively, revealed a significant difference between Cox and Kaplan-Meier (P neural network, and the neural network and the standard (Kaplan-Meier), as well as better accuracy for the neural network (with 3 nodes in the hidden layer

  20. Estimating the reproducibility of psychological science

    NARCIS (Netherlands)

    Aarts, Alexander A.; Anderson, Joanna E.; Anderson, Christopher J.; Attridge, Peter R.; Attwood, Angela; Axt, Jordan; Babel, Molly; Bahník, Štěpán; Baranski, Erica; Barnett-Cowan, Michael; Bartmess, Elizabeth; Beer, Jennifer; Bell, Raoul; Bentley, Heather; Beyan, Leah; Binion, Grace; Borsboom, Denny; Bosch, Annick; Bosco, Frank A.; Bowman, Sara D.; Brandt, Mark J.; Braswell, Erin; Brohmer, Hilmar; Brown, Benjamin T.; Brown, Kristina; Brüning, Jovita; Calhoun-Sauls, Ann; Callahan, Shannon P.; Chagnon, Elizabeth; Chandler, Jesse; Chartier, Christopher R.; Cheung, Felix; Christopherson, Cody D.; Cillessen, Linda; Clay, Russ; Cleary, Hayley; Cloud, Mark D.; Conn, Michael; Cohoon, Johanna; Columbus, Simon; Cordes, Andreas; Costantini, Giulio; Alvarez, Leslie D Cramblet; Cremata, Ed; Crusius, Jan; DeCoster, Jamie; DeGaetano, Michelle A.; Penna, Nicolás Delia; Den Bezemer, Bobby; Deserno, Marie K.; Devitt, Olivia; Dewitte, Laura; Dobolyi, David G.; Dodson, Geneva T.; Donnellan, M. Brent; Donohue, Ryan; Dore, Rebecca A.; Dorrough, Angela; Dreber, Anna; Dugas, Michelle; Dunn, Elizabeth W.; Easey, Kayleigh; Eboigbe, Sylvia; Eggleston, Casey; Embley, Jo; Epskamp, Sacha; Errington, Timothy M.; Estel, Vivien; Farach, Frank J.; Feather, Jenelle; Fedor, Anna; Fernández-Castilla, Belén; Fiedler, Susann; Field, James G.; Fitneva, Stanka A.; Flagan, Taru; Forest, Amanda L.; Forsell, Eskil; Foster, Joshua D.; Frank, Michael C.; Frazier, Rebecca S.; Fuchs, Heather; Gable, Philip; Galak, Jeff; Galliani, Elisa Maria; Gampa, Anup; Garcia, Sara; Gazarian, Douglas; Gilbert, Elizabeth; Giner-Sorolla, Roger; Glöckner, Andreas; Goellner, Lars; Goh, Jin X.; Goldberg, Rebecca; Goodbourn, Patrick T.; Gordon-McKeon, Shauna; Gorges, Bryan; Gorges, Jessie; Goss, Justin; Graham, Jesse; Grange, James A.; Gray, Jeremy; Hartgerink, Chris; Hartshorne, Joshua; Hasselman, Fred; Hayes, Timothy; Heikensten, Emma; Henninger, Felix; Hodsoll, John; Holubar, Taylor; Hoogendoorn, Gea; Humphries, Denise J.; Hung, Cathy O Y; Immelman, Nathali; Irsik, Vanessa C.; Jahn, Georg; Jäkel, Frank; Jekel, Marc; Johannesson, Magnus; Johnson, Larissa G.; Johnson, David J.; Johnson, Kate M.; Johnston, William J.; Jonas, Kai; Joy-Gaba, Jennifer A.; Kappes, Heather Barry; Kelso, Kim; Kidwell, Mallory C.; Kim, Seung Kyung; Kirkhart, Matthew; Kleinberg, Bennett; Knežević, Goran; Kolorz, Franziska Maria; Kossakowski, Jolanda J.; Krause, Robert Wilhelm; Krijnen, Job; Kuhlmann, Tim; Kunkels, Yoram K.; Kyc, Megan M.; Lai, Calvin K.; Laique, Aamir; Lakens, Daniël; Lane, Kristin A.; Lassetter, Bethany; Lazarević, Ljiljana B.; Le Bel, Etienne P.; Lee, Key Jung; Lee, Minha; Lemm, Kristi; Levitan, Carmel A.; Lewis, Melissa; Lin, Lin; Lin, Stephanie; Lippold, Matthias; Loureiro, Darren; Luteijn, Ilse; MacKinnon, Sean; Mainard, Heather N.; Marigold, Denise C.; Martin, Daniel P.; Martinez, Tylar; Masicampo, E. J.; Matacotta, Josh; Mathur, Maya; May, Michael; Mechin, Nicole; Mehta, Pranjal; Meixner, Johannes; Melinger, Alissa; Miller, Jeremy K.; Miller, Mallorie; Moore, Katherine; Möschl, Marcus; Motyl, Matt; Müller, Stephanie M.; Munafo, Marcus; Neijenhuijs, Koen I.; Nervi, Taylor; Nicolas, Gandalf; Nilsonne, Gustav; Nosek, Brian A.; Nuijten, Michèle B.; Olsson, Catherine; Osborne, Colleen; Ostkamp, Lutz; Pavel, Misha; Penton-Voak, Ian S.; Perna, Olivia; Pernet, Cyril; Perugini, Marco; Pipitone, R. Nathan; Pitts, Michael C.; Plessow, Franziska; Prenoveau, Jason M.; Rahal, Rima Maria; Ratliff, Kate A.; Reinhard, David; Renkewitz, Frank; Ricker, Ashley A.; Rigney, Anastasia; Rivers, Andrew M.; Roebke, Mark; Rutchick, Abraham M.; Ryan, Robert S.; Sahin, Onur; Saide, Anondah; Sandstrom, Gillian M.; Santos, David; Saxe, Rebecca; Schlegelmilch, René; Schmidt, Kathleen; Scholz, Sabine; Seibel, Larissa; Selterman, Dylan Faulkner; Shaki, Samuel; Simpson, William B.; Sinclair, H. Colleen; Skorinko, Jeanine L M; Slowik, Agnieszka; Snyder, Joel S.; Soderberg, Courtney; Sonnleitner, Carina; Spencer, Nick; Spies, Jeffrey R.; Steegen, Sara; Stieger, Stefan; Strohminger, Nina; Sullivan, Gavin B.; Talhelm, Thomas; Tapia, Megan; Te Dorsthorst, Anniek; Thomae, Manuela; Thomas, Sarah L.; Tio, Pia; Traets, Frits; Tsang, Steve; Tuerlinckx, Francis; Turchan, Paul; Valášek, Milan; Van't Veer, Anna E.; Van Aert, Robbie; Van Assen, Marcel; Van Bork, Riet; Van De Ven, Mathijs; Van Den Bergh, Don; Van Der Hulst, Marije; Van Dooren, Roel; Van Doorn, Johnny; Van Renswoude, Daan R.; Van Rijn, Hedderik; Vanpaemel, Wolf; Echeverría, Alejandro Vásquez; Vazquez, Melissa; Velez, Natalia; Vermue, Marieke; Verschoor, Mark; Vianello, Michelangelo; Voracek, Martin; Vuu, Gina; Wagenmakers, Eric-Jan; Weerdmeester, Joanneke; Welsh, Ashlee; Westgate, Erin C.; Wissink, Joeri; Wood, Michael; Woods, Andy; Wright, Emily; Wu, Sining; Zeelenberg, Marcel; Zuni, Kellylynn

    2015-01-01

    Reproducibility is a defining feature of science, but the extent to which it characterizes current research is unknown. We conducted replications of 100 experimental and correlational studies published in three psychology journals using high-powered designs and original materials when available.

  1. Estimating the reproducibility of psychological science

    NARCIS (Netherlands)

    Aarts, Alexander A.; Anderson, Joanna E.; Anderson, Christopher J.; Attridge, Peter R.; Attwood, Angela; Axt, Jordan; Babel, Molly; Bahnik, Stepan; Baranski, Erica; Barnett-Cowan, Michael; Bartmess, Elizabeth; Beer, Jennifer; Bell, Raoul; Bentley, Heather; Beyan, Leah; Binion, Grace; Borsboom, Denny; Bosch, Annick; Bosco, Frank A.; Bowman, Sara D.; Brandt, Mark J.; Braswell, Erin; Brohmer, Hilmar; Brown, Benjamin T.; Brown, Kristina; Bruening, Jovita; Calhoun-Sauls, Ann; Chagnon, Elizabeth; Callahan, Shannon P.; Chandler, Jesse; Chartier, Christopher R.; Cheung, Felix; Cillessen, Linda; Christopherson, Cody D.; Clay, Russ; Cleary, Hayley; Cloud, Mark D.; Cohn, Michael; Cohoon, Johanna; Columbus, Simon; Cordes, Andreas; Costantini, Giulio; Hartgerink, Chris; Krijnen, Job; Nuijten, Michele B.; van 't Veer, Anna E.; Van Aert, Robbie; van Assen, M.A.L.M.; Wissink, Joeri; Zeelenberg, Marcel

    2015-01-01

    INTRODUCTION Reproducibility is a defining feature of science, but the extent to which it characterizes current research is unknown. Scientific claims should not gain credence because of the status or authority of their originator but by the replicability of their supporting evidence. Even research

  2. REPRODUCIBILITY OF CHILDHOOD RESPIRATORY SYMPTOM QUESTIONS

    NARCIS (Netherlands)

    BRUNEKREEF, B; GROOT, B; RIJCKEN, B; HOEK, G; STEENBEKKERS, A; DEBOER, A

    The reproducibility of answers to childhood respiratory symptom questions was investigated by administering two childhood respiratory symptom questionnaires twice, with a one month interval, to the same population of Dutch school children. The questionnaires were completed by the parents of 410

  3. Reply to the comment of S. Rayne on "QSAR model reproducibility and applicability: A case study of rate constants of hydroxyl radical reaction models applied to polybrominated diphenyl ethers and (benzo-)triazoles".

    Science.gov (United States)

    Gramatica, Paola; Kovarich, Simona; Roy, Partha Pratim

    2013-07-30

    We appreciate the interest of Dr. Rayne on our article and we completely agree that the dataset of (benzo-)triazoles, which were screened by the hydroxyl radical reaction quantitative structure-activity relationship (QSAR) model, was not only composed of benzo-triazoles but also included some simpler triazoles (without the condensed benzene ring), such as the chemicals listed by Dr. Rayne, as well as some related heterocycles (also few not aromatic). We want to clarify that in this article (as well as in other articles in which the same dataset was screened), for conciseness, the abbreviations (B)TAZs and BTAZs were used as general (and certainly too simplified) notations meaning an extended dataset of benzo-triazoles, triazoles, and related compounds. Copyright © 2013 Wiley Periodicals, Inc.

  4. The role of empathy and emotional intelligence in nurses' communication attitudes using regression models and fuzzy-set qualitative comparative analysis models (fsQCA).

    Science.gov (United States)

    Del Carmen Giménez-Espert, María; Prado-Gascó, Vicente Javier

    2018-03-01

    To analyse link between empathy and emotional intelligence (EI) as a predictor of nurses' attitudes towards communication while comparing the contribution of emotional aspects and attitudinal elements on potential behaviour. Nurses' attitudes towards communication, empathy and emotional intelligence are key skills for nurses involved in patient care. There are currently no studies analysing this link, and its investigation is needed because attitudes may influence communication behaviours. Correlational study. To attain this goal, self-reported instruments (attitudes towards communication of nurses (ACO), trait emotional intelligence (TMMS24), and Jefferson-scale empathy (JSNE)) were collected from 460 nurses between September 2015 and February 2016. Two different analytical methodologies were used: traditional regression models and fuzzy-set qualitative comparative analysis models (fsQCA). The results of the regression model suggest that cognitive dimensions of attitude are a significant and positive predictor of the behavioural dimension. The perspective-taking dimension of empathy and the emotional-clarity dimension of emotional intelligence were significant positive predictors of the dimensions of attitudes towards communication, except for the affective dimension (for which the association was negative). The results of the fsQCA models confirm that the combination of high levels of cognitive dimension of attitudes, perspective-taking and emotional clarity explained high levels of the behavioural dimension of attitude. Empathy and EI are predictors of nurses' attitudes towards communication, and the cognitive dimension of attitude is a good predictor of the behavioural dimension of ACO in both regression models and fsQCA. In general, the fsQCA models appear to be better predictors than the regression models are. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  5. ITK: enabling reproducible research and open science

    Science.gov (United States)

    McCormick, Matthew; Liu, Xiaoxiao; Jomier, Julien; Marion, Charles; Ibanez, Luis

    2014-01-01

    Reproducibility verification is essential to the practice of the scientific method. Researchers report their findings, which are strengthened as other independent groups in the scientific community share similar outcomes. In the many scientific fields where software has become a fundamental tool for capturing and analyzing data, this requirement of reproducibility implies that reliable and comprehensive software platforms and tools should be made available to the scientific community. The tools will empower them and the public to verify, through practice, the reproducibility of observations that are reported in the scientific literature. Medical image analysis is one of the fields in which the use of computational resources, both software and hardware, are an essential platform for performing experimental work. In this arena, the introduction of the Insight Toolkit (ITK) in 1999 has transformed the field and facilitates its progress by accelerating the rate at which algorithmic implementations are developed, tested, disseminated and improved. By building on the efficiency and quality of open source methodologies, ITK has provided the medical image community with an effective platform on which to build a daily workflow that incorporates the true scientific practices of reproducibility verification. This article describes the multiple tools, methodologies, and practices that the ITK community has adopted, refined, and followed during the past decade, in order to become one of the research communities with the most modern reproducibility verification infrastructure. For example, 207 contributors have created over 2400 unit tests that provide over 84% code line test coverage. The Insight Journal, an open publication journal associated with the toolkit, has seen over 360,000 publication downloads. The median normalized closeness centrality, a measure of knowledge flow, resulting from the distributed peer code review system was high, 0.46. PMID:24600387

  6. ITK: Enabling Reproducible Research and Open Science

    Directory of Open Access Journals (Sweden)

    Matthew Michael McCormick

    2014-02-01

    Full Text Available Reproducibility verification is essential to the practice of the scientific method. Researchers report their findings, which are strengthened as other independent groups in the scientific community share similar outcomes. In the many scientific fields where software has become a fundamental tool for capturing and analyzing data, this requirement of reproducibility implies that reliable and comprehensive software platforms and tools should be made available to the scientific community. The tools will empower them and the public to verify, through practice, the reproducibility of observations that are reported in the scientific literature.Medical image analysis is one of the fields in which the use of computational resources, both software and hardware, are an essential platform for performing experimental work. In this arena, the introduction of the Insight Toolkit (ITK in 1999 has transformed the field and facilitates its progress by accelerating the rate at which algorithmic implementations are developed, tested, disseminated and improved. By building on the efficiency and quality of open source methodologies, ITK has provided the medical image community with an effective platform on which to build a daily workflow that incorporates the true scientific practices of reproducibility verification.This article describes the multiple tools, methodologies, and practices that the ITK community has adopted, refined, and followed during the past decade, in order to become one of the research communities with the most modern reproducibility verification infrastructure. For example, 207 contributors have created over 2400 unit tests that provide over 84% code line test coverage. The Insight Journal, an open publication journal associated with the toolkit, has seen over 360,000 publication downloads. The median normalized closeness centrality, a measure of knowledge flow, resulting from the distributed peer code review system was high, 0.46.

  7. A PHYSICAL ACTIVITY QUESTIONNAIRE: REPRODUCIBILITY AND VALIDITY

    Directory of Open Access Journals (Sweden)

    Nicolas Barbosa

    2007-12-01

    Full Text Available This study evaluates the Quantification de L'Activite Physique en Altitude chez les Enfants (QAPACE supervised self-administered questionnaire reproducibility and validity on the estimation of the mean daily energy expenditure (DEE on Bogotá's schoolchildren. The comprehension was assessed on 324 students, whereas the reproducibility was studied on a different random sample of 162 who were exposed twice to it. Reproducibility was assessed using both the Bland-Altman plot and the intra-class correlation coefficient (ICC. The validity was studied in a sample of 18 girls and 18 boys randomly selected, which completed the test - re-test study. The DEE derived from the questionnaire was compared with the laboratory measurement results of the peak oxygen uptake (Peak VO2 from ergo-spirometry and Leger Test. The reproducibility ICC was 0.96 (95% C.I. 0.95-0.97; by age categories 8-10, 0.94 (0.89-0. 97; 11-13, 0.98 (0.96- 0.99; 14-16, 0.95 (0.91-0.98. The ICC between mean TEE as estimated by the questionnaire and the direct and indirect Peak VO2 was 0.76 (0.66 (p<0.01; by age categories, 8-10, 11-13, and 14-16 were 0.89 (0.87, 0.76 (0.78 and 0.88 (0.80 respectively. The QAPACE questionnaire is reproducible and valid for estimating PA and showed a high correlation with the Peak VO2 uptake

  8. The Danube Delta Biosphere Reserve Qualitative Reasoning Model - Education and Decision Support tool for Active Behaviour in Sustainable Development of this area

    Directory of Open Access Journals (Sweden)

    CIOACA Eugenia

    2007-10-01

    Full Text Available This paper presents the three main steps necessary in preparing a new model based on Qualitative Reasoning (QR concept, for Danube Delta Biosphere Reserve (DDBR environmental system. These are: theDDBR system Concept map, the Global causal model, and the Structural model. The DDBR QR model is focused on describing the behaviour of this system related to those causes and their effects which hamper the system sustainable development, especially this system aquatic ecosystem behaviour governed by the water pollution process positive rate and its negative effect on biodiversity and human being health, for peolple living in oraround this area.

  9. Accuracy, reproducibility, and time efficiency of dental measurements using different technologies.

    Science.gov (United States)

    Grünheid, Thorsten; Patel, Nishant; De Felippe, Nanci L; Wey, Andrew; Gaillard, Philippe R; Larson, Brent E

    2014-02-01

    Historically, orthodontists have taken dental measurements on plaster models. Technological advances now allow orthodontists to take these measurements on digital models. In this study, we aimed to assess the accuracy, reproducibility, and time efficiency of dental measurements taken on 3 types of digital models. emodels (GeoDigm, Falcon Heights, Minn), SureSmile models (OraMetrix, Richardson, Tex), and AnatoModels (Anatomage, San Jose, Calif) were made for 30 patients. Mesiodistal tooth-width measurements taken on these digital models were timed and compared with those on the corresponding plaster models, which were used as the gold standard. Accuracy and reproducibility were assessed using the Bland-Altman method. Differences in time efficiency were tested for statistical significance with 1-way analysis of variance. Measurements on SureSmile models were the most accurate, followed by those on emodels and AnatoModels. Measurements taken on SureSmile models were also the most reproducible. Measurements taken on SureSmile models and emodels were significantly faster than those taken on AnatoModels and plaster models. Tooth-width measurements on digital models can be as accurate as, and might be more reproducible and significantly faster than, those taken on plaster models. Of the models studied, the SureSmile models provided the best combination of accuracy, reproducibility, and time efficiency of measurement. Copyright © 2014 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

  10. Reproducibility of the chamber scarification test

    DEFF Research Database (Denmark)

    Andersen, Klaus Ejner

    1996-01-01

    The chamber scarification test is a predictive human skin irritation test developed to rank the irritation potential of products and ingredients meant for repeated use on normal and diseased skin. 12 products or ingredients can be tested simultaneously on the forearm skin of each volunteer....... The test combines with the procedure scratching of the skin at each test site and subsequent closed patch tests with the products, repeated daily for 3 days. The test is performed on groups of human volunteers: a skin irritant substance or products is included in each test as a positive control...... high reproducibility of the test. Further, intra-individual variation in skin reaction to the 2 control products in 26 volunteers, who participated 2x, is shown, which supports the conclusion that the chamber scarification test is a useful short-term human skin irritation test with high reproducibility....

  11. Reproducibility of scoring emphysema by HRCT

    Energy Technology Data Exchange (ETDEWEB)

    Malinen, A.; Partanen, K.; Rytkoenen, H.; Vanninen, R. [Kuopio Univ. Hospital (Finland). Dept. of Clinical Radiology; Erkinjuntti-Pekkanen, R. [Kuopio Univ. Hospital (Finland). Dept. of Pulmonary Diseases

    2002-04-01

    Purpose: We evaluated the reproducibility of three visual scoring methods of emphysema and compared these methods with pulmonary function tests (VC, DLCO, FEV1 and FEV%) among farmer's lung patients and farmers. Material and Methods: Three radiologists examined high-resolution CT images of farmer's lung patients and their matched controls (n=70) for chronic interstitial lung diseases. Intraobserver reproducibility and interobserver variability were assessed for three methods: severity, Sanders' (extent) and Sakai. Pulmonary function tests as spirometry and diffusing capacity were measured. Results: Intraobserver -values for all three methods were good (0.51-0.74). Interobserver varied from 0.35 to 0.72. The Sanders' and the severity methods correlated strongly with pulmonary function tests, especially DLCO and FEV1. Conclusion: The Sanders' method proved to be reliable in evaluating emphysema, in terms of good consistency of interpretation and good correlation with pulmonary function tests.

  12. Reproducibility of scoring emphysema by HRCT

    International Nuclear Information System (INIS)

    Malinen, A.; Partanen, K.; Rytkoenen, H.; Vanninen, R.; Erkinjuntti-Pekkanen, R.

    2002-01-01

    Purpose: We evaluated the reproducibility of three visual scoring methods of emphysema and compared these methods with pulmonary function tests (VC, DLCO, FEV1 and FEV%) among farmer's lung patients and farmers. Material and Methods: Three radiologists examined high-resolution CT images of farmer's lung patients and their matched controls (n=70) for chronic interstitial lung diseases. Intraobserver reproducibility and interobserver variability were assessed for three methods: severity, Sanders' (extent) and Sakai. Pulmonary function tests as spirometry and diffusing capacity were measured. Results: Intraobserver -values for all three methods were good (0.51-0.74). Interobserver varied from 0.35 to 0.72. The Sanders' and the severity methods correlated strongly with pulmonary function tests, especially DLCO and FEV1. Conclusion: The Sanders' method proved to be reliable in evaluating emphysema, in terms of good consistency of interpretation and good correlation with pulmonary function tests

  13. Additive Manufacturing: Reproducibility of Metallic Parts

    Directory of Open Access Journals (Sweden)

    Konda Gokuldoss Prashanth

    2017-02-01

    Full Text Available The present study deals with the properties of five different metals/alloys (Al-12Si, Cu-10Sn and 316L—face centered cubic structure, CoCrMo and commercially pure Ti (CP-Ti—hexagonal closed packed structure fabricated by selective laser melting. The room temperature tensile properties of Al-12Si samples show good consistency in results within the experimental errors. Similar reproducible results were observed for sliding wear and corrosion experiments. The other metal/alloy systems also show repeatable tensile properties, with the tensile curves overlapping until the yield point. The curves may then follow the same path or show a marginal deviation (~10 MPa until they reach the ultimate tensile strength and a negligible difference in ductility levels (of ~0.3% is observed between the samples. The results show that selective laser melting is a reliable fabrication method to produce metallic materials with consistent and reproducible properties.

  14. Health beliefs about lifestyle habits differ between patients and spouses 1 year after a cardiac event - a qualitative analysis based on the Health Belief Model.

    Science.gov (United States)

    Köhler, Anita Kärner; Nilsson, Staffan; Jaarsma, Tiny; Tingström, Pia

    2017-06-01

    Spousal concordance on risk factors and lifestyle habits exists and can partly be explained by patients' and spouses' health beliefs and underuse of cardiac rehabilitation. However, there have been very few qualitative comparisons of health beliefs between patients and spouses after a cardiac event. To examine and qualitatively compare the health beliefs of patients with coronary heart disease and their spouses about lifestyle habits, 1 year after the cardiac event. Explorative and descriptive. Semi-structured focus group interviews were conducted with patients (n = 14) 1 year after a cardiac event, as well as individual interviews with spouses (n = 8). The transcriptions underwent a deductive qualitative content analysis, within the framework of the Health Belief Model. Patients' and spouses' health beliefs about lifestyle habits qualitatively differed in most predetermined main analytical categories of the Health Belief Model. The patients relied more on their own capacity and the healthcare system than on collaboration with their spouses who instead emphasised the importance of mutual activities to establish lifestyle habits. The spouses therefore experienced problems with different family preferences compared to the patients' wishes. Moreover, only patients believed supervised exercise was beneficial for risk reduction of coronary heart disease and they related barriers for medication to a self-healing body and a meaningless life without relatives and old habits. Patients and spouses agreed that despite the severity of illness, life was captured and that normalisation to a life as usual was possible. The patients' and spouses' qualitatively different health beliefs regarding health-related behaviours imply a new approach. Nurses and associated professionals need to follow-up patients' and spouses' in primary health care to support them in a tailored way, for example in problem-based sessions. Recognition and understanding of their different views and otherness

  15. Reproducibility of 201Tl myocardial imaging

    International Nuclear Information System (INIS)

    McLaughlin, P.R.; Martin, R.P.; Doherty, P.; Daspit, S.; Goris, M.; Haskell, W.; Lewis, S.; Kriss, J.P.; Harrison, D.C.

    1977-01-01

    Seventy-six thallium-201 myocardial perfusion studies were performed on twenty-five patients to assess their reproducibility and the effect of varying the level of exercise on the results of imaging. Each patient had a thallium-201 study at rest. Fourteen patients had studies on two occasions at maximum exercise, and twelve patients had studies both at light and at maximum exercise. Of 70 segments in the 14 patients assessed on each of two maximum exercise tests, 64 (91 percent) were reproducible. Only 53 percent (16/30) of the ischemic defects present at maximum exercise were seen in the light exercise study in the 12 patients assessed at two levels of exercise. Correlation of perfusion defects with arteriographically proven significant coronary stenosis was good for the left anterior descending and right coronary arteries, but not as good for circumflex artery disease. Thallium-201 myocardial imaging at maximum exercise is reproducible within acceptable limits, but careful attention to exercise technique is essential for valid comparative studies

  16. A Framework for Reproducible Latent Fingerprint Enhancements.

    Science.gov (United States)

    Carasso, Alfred S

    2014-01-01

    Photoshop processing of latent fingerprints is the preferred methodology among law enforcement forensic experts, but that appproach is not fully reproducible and may lead to questionable enhancements. Alternative, independent, fully reproducible enhancements, using IDL Histogram Equalization and IDL Adaptive Histogram Equalization, can produce better-defined ridge structures, along with considerable background information. Applying a systematic slow motion smoothing procedure to such IDL enhancements, based on the rapid FFT solution of a Lévy stable fractional diffusion equation, can attenuate background detail while preserving ridge information. The resulting smoothed latent print enhancements are comparable to, but distinct from, forensic Photoshop images suitable for input into automated fingerprint identification systems, (AFIS). In addition, this progressive smoothing procedure can be reexamined by displaying the suite of progressively smoother IDL images. That suite can be stored, providing an audit trail that allows monitoring for possible loss of useful information, in transit to the user-selected optimal image. Such independent and fully reproducible enhancements provide a valuable frame of reference that may be helpful in informing, complementing, and possibly validating the forensic Photoshop methodology.

  17. Fluctuation-Driven Neural Dynamics Reproduce Drosophila Locomotor Patterns.

    Directory of Open Access Journals (Sweden)

    Andrea Maesani

    2015-11-01

    Full Text Available The neural mechanisms determining the timing of even simple actions, such as when to walk or rest, are largely mysterious. One intriguing, but untested, hypothesis posits a role for ongoing activity fluctuations in neurons of central action selection circuits that drive animal behavior from moment to moment. To examine how fluctuating activity can contribute to action timing, we paired high-resolution measurements of freely walking Drosophila melanogaster with data-driven neural network modeling and dynamical systems analysis. We generated fluctuation-driven network models whose outputs-locomotor bouts-matched those measured from sensory-deprived Drosophila. From these models, we identified those that could also reproduce a second, unrelated dataset: the complex time-course of odor-evoked walking for genetically diverse Drosophila strains. Dynamical models that best reproduced both Drosophila basal and odor-evoked locomotor patterns exhibited specific characteristics. First, ongoing fluctuations were required. In a stochastic resonance-like manner, these fluctuations allowed neural activity to escape stable equilibria and to exceed a threshold for locomotion. Second, odor-induced shifts of equilibria in these models caused a depression in locomotor frequency following olfactory stimulation. Our models predict that activity fluctuations in action selection circuits cause behavioral output to more closely match sensory drive and may therefore enhance navigation in complex sensory environments. Together these data reveal how simple neural dynamics, when coupled with activity fluctuations, can give rise to complex patterns of animal behavior.

  18. Pushing for Particulate Level Models of Adiabatic and Isothermal Processes in Upper-Level Chemistry Courses: A Qualitative Study

    Science.gov (United States)

    Hernandez, Gabriel E.; Criswell, Brett A.; Kirk, Nancy J.; Sauder, Deborah G.; Rushton, Gregory T.

    2014-01-01

    In the past three decades, researchers have noted the limitations of a problem-solving approach that overemphasizes algorithms and quantitation and neglects student misconceptions and an otherwise qualitative, conceptual understanding of chemical phenomena. Since then, studies and lessons designed to improve student understanding of chemistry has…

  19. Automated Generation of Technical Documentation and Provenance for Reproducible Research

    Science.gov (United States)

    Jolly, B.; Medyckyj-Scott, D.; Spiekermann, R.; Ausseil, A. G.

    2017-12-01

    Data provenance and detailed technical documentation are essential components of high-quality reproducible research, however are often only partially addressed during a research project. Recording and maintaining this information during the course of a project can be a difficult task to get right as it is a time consuming and often boring process for the researchers involved. As a result, provenance records and technical documentation provided alongside research results can be incomplete or may not be completely consistent with the actual processes followed. While providing access to the data and code used by the original researchers goes some way toward enabling reproducibility, this does not count as, or replace, data provenance. Additionally, this can be a poor substitute for good technical documentation and is often more difficult for a third-party to understand - particularly if they do not understand the programming language(s) used. We present and discuss a tool built from the ground up for the production of well-documented and reproducible spatial datasets that are created by applying a series of classification rules to a number of input layers. The internal model of the classification rules required by the tool to process the input data is exploited to also produce technical documentation and provenance records with minimal additional user input. Available provenance records that accompany input datasets are incorporated into those that describe the current process. As a result, each time a new iteration of the analysis is performed the documentation and provenance records are re-generated to provide an accurate description of the exact process followed. The generic nature of this tool, and the lessons learned during its creation, have wider application to other fields where the production of derivative datasets must be done in an open, defensible, and reproducible way.

  20. Open and reproducible global land use classification

    Science.gov (United States)

    Nüst, Daniel; Václavík, Tomáš; Pross, Benjamin

    2015-04-01

    Researchers led by the Helmholtz Centre for Environmental research (UFZ) developed a new world map of land use systems based on over 30 diverse indicators (http://geoportal.glues.geo.tu-dresden.de/stories/landsystemarchetypes.html) of land use intensity, climate and environmental and socioeconomic factors. They identified twelve land system archetypes (LSA) using a data-driven classification algorithm (self-organizing maps) to assess global impacts of land use on the environment, and found unexpected similarities across global regions. We present how the algorithm behind this analysis can be published as an executable web process using 52°North WPS4R (https://wiki.52north.org/bin/view/Geostatistics/WPS4R) within the GLUES project (http://modul-a.nachhaltiges-landmanagement.de/en/scientific-coordination-glues/). WPS4R is an open source collaboration platform for researchers, analysts and software developers to publish R scripts (http://www.r-project.org/) as a geo-enabled OGC Web Processing Service (WPS) process. The interoperable interface to call the geoprocess allows both reproducibility of the analysis and integration of user data without knowledge about web services or classification algorithms. The open platform allows everybody to replicate the analysis in their own environments. The LSA WPS process has several input parameters, which can be changed via a simple web interface. The input parameters are used to configure both the WPS environment and the LSA algorithm itself. The encapsulation as a web process allows integration of non-public datasets, while at the same time the publication requires a well-defined documentation of the analysis. We demonstrate this platform specifically to domain scientists and show how reproducibility and open source publication of analyses can be enhanced. We also discuss future extensions of the reproducible land use classification, such as the possibility for users to enter their own areas of interest to the system and

  1. Queer nuclear families? Reproducing and transgressing heteronormativity.

    Science.gov (United States)

    Folgerø, Tor

    2008-01-01

    During the past decade the public debate on gay and lesbian adoptive rights has been extensive in the Norwegian media. The debate illustrates how women and men planning to raise children in homosexual family constellations challenge prevailing cultural norms and existing concepts of kinship and family. The article discusses how lesbian mothers and gay fathers understand and redefine their own family practices. An essential point in this article is the fundamental ambiguity in these families' accounts of themselves-how they simultaneously transgress and reproduce heteronormative assumptions about childhood, fatherhood, motherhood, family and kinship.

  2. Assessment of the relationships between morphometric characteristics of relief with quantitative and qualitative characteristics of forests using ASTER and SRTM digital terrain models

    Directory of Open Access Journals (Sweden)

    D. M. Chernikhovsky

    2017-06-01

    Full Text Available In the article are shown results of assessment of relationships between quantitative and qualitative characteristics of forests and morphometric characteristics of relief on an example model plot in Nanayskoe forest district of Khabarovsk Territory. The relevance of the investigation is connected with need for improvement of the system of forest evaluation operations in the Russian Federation, including with use of the landscape approach. The tasks of the investigation were assessment of relationships between characteristics of relief and characteristics of forest vegetation cover on different levels of forest management; evaluation of morphometric characteristics of relief are important for structure and productivity of forests; comparison of the results obtained through the use of digital terrain models ASTER and SRTM. Geoinformatic projects were formed for a model plot on the basis of digital terrain models and data of forest mensuration and State (National Forest Inventory. On the basis of the developed method with use geoinformatic technologies were estimated morphometric characteristics of relief (average height, standard deviation of height, entropy, exposition and gradient of slopes, indexes of ruggedness and roughness, quantitative and qualitative characteristics of forests. The multifactor regression analysis, where characteristics of forests (as dependent variables and morphometric characteristics of relief (as independent variables were used, have been done. As a result of research, the set of morphometric characteristics of relief able to influence to variability of quantitative and qualitative characteristics of forests was identified. The set of linear regression equations able to explain 30–50 % of variability of dependent variables was obtained. The regression equations, obtained on base of digital terrain models ASTER and SRTM, comparable to each other in strength of relations (coefficients of determination, but includes the

  3. Efficient and reproducible identification of mismatch repair deficient colon cancer

    DEFF Research Database (Denmark)

    Joost, Patrick; Bendahl, Pär-Ola; Halvarsson, Britta

    2013-01-01

    BACKGROUND: The identification of mismatch-repair (MMR) defective colon cancer is clinically relevant for diagnostic, prognostic and potentially also for treatment predictive purposes. Preselection of tumors for MMR analysis can be obtained with predictive models, which need to demonstrate ease...... of application and favorable reproducibility. METHODS: We validated the MMR index for the identification of prognostically favorable MMR deficient colon cancers and compared performance to 5 other prediction models. In total, 474 colon cancers diagnosed ≥ age 50 were evaluated with correlation between...... and efficiently identifies MMR defective colon cancers with high sensitivity and specificity. The model shows stable performance with low inter-observer variability and favorable performance when compared to other MMR predictive models....

  4. An Evaluation Model of Quantitative and Qualitative Fuzzy Multi-Criteria Decision-Making Approach for Location Selection of Transshipment Ports

    Directory of Open Access Journals (Sweden)

    Ji-Feng Ding

    2013-01-01

    Full Text Available The role of container logistics centre as home bases for merchandise transportation has become increasingly important. The container carriers need to select a suitable centre location of transshipment port to meet the requirements of container shipping logistics. In the light of this, the main purpose of this paper is to develop a fuzzy multi-criteria decision-making (MCDM model to evaluate the best selection of transshipment ports for container carriers. At first, some concepts and methods used to develop the proposed model are briefly introduced. The performance values of quantitative and qualitative subcriteria are discussed to evaluate the fuzzy ratings. Then, the ideal and anti-ideal concepts and the modified distance measure method are used in the proposed model. Finally, a step-by-step example is illustrated to study the computational process of the quantitative and qualitative fuzzy MCDM model. The proposed approach has successfully accomplished our goal. In addition, the proposed fuzzy MCDM model can be empirically employed to select the best location of transshipment port for container carriers in the future study.

  5. Timbral aspects of reproduced sound in small rooms. I

    DEFF Research Database (Denmark)

    Bech, Søren

    1995-01-01

    This paper reports some of the influences of individual reflections on the timbre of reproduced sound. A single loudspeaker with frequency-independent directivity characteristics, positioned in a listening room of normal size with frequency-independent absorption coefficients of the room surfaces......, has been simulated using an electroacoustic setup. The model included the direct sound, 17 individual reflections, and the reverberant field. The threshold of detection and just-noticeable differences for an increase in level were measured for individual reflections using eight subjects for noise...

  6. Qualitative Analysis of the Goodwin Model of the Growth Cycle || Análisis cualitativo del modelo de Goodwin de ciclos de crecimiento

    Directory of Open Access Journals (Sweden)

    Serebriakov, Vladimir

    2017-06-01

    Full Text Available Goodwin's model is a set of ordinary differential equations and is a well-known model of the growth cycle. However, its four constants require an extensive numerical study of its two differential equations to identify all possible unsteady state behaviors, i.e. phase portraits, which corresponds to infinitely many combinations of numerical values of the constants. Qualitative interpretation of Goodwin's model solves these problems by replacing all numerical constants and all derivatives by trends (increasing, constant and decreasing. The model has two variables - the employment rate V, and the labour share U. A solution of the qualitative Goodwin's model is a scenario. An example of a Goodwin's scenario is - V is increasing more and more rapidly, U is decreasing and the decrease is slowing down. The complete set of all possible 41 Goodwin's scenarios and 168 time transitions among them are given. This result qualitatively represents all possible unsteady state Goodwin's behaviours. It is therefore possible to predict all possible future behaviours if a current behaviour is known/chosen. A prediction example is presented in details. No prior knowledge of qualitative model theory is required. || El modelo de Goodwin es un conjunto de ecuaciones diferenciales ordinarias y resulta un modelo bien conocido para ciclos de crecimiento. Sin embargo, sus cuatro constantes requieren de un extenso estudio numérico de sus dos ecuaciones diferenciales para identificar todos los posibles comportamientos de estado no estacionario, i.e. retratos de fase, que corresponden a infinitamente muchas combinaciones de valores numéricos de las constantes. La interpretación cualitativa del modelo de Goodwin resuelve estos problemas reemplazando todas las constantes numéricas y todas las derivadas por tendencias (creciente, constante y decreciente. El modelo consiste en dos variables: la tasa de empleabilidad V y la repartición del valor agregado U. Una solución del

  7. Is the promise of methadone Kenya’s solution to managing HIV and addiction? A mixed-method mathematical modelling and qualitative study

    Science.gov (United States)

    Rhodes, Tim; Guise, Andy; Ndimbii, James; Strathdee, Steffanie; Ngugi, Elizabeth; Platt, Lucy; Kurth, Ann; Cleland, Charles; Vickerman, Peter

    2015-01-01

    Background and objectives Promoted globally as an evidence-based intervention in the prevention of HIV and treatment of heroin addiction among people who inject drugs (PWID), opioid substitution treatment (OST) can help control emerging HIV epidemics among PWID. With implementation in December 2014, Kenya is the third Sub-Saharan African country to have introduced OST. We combine dynamic mathematical modelling with qualitative sociological research to examine the ‘promise of methadone’ to Kenya. Methods, setting and participants We model the HIV prevention impact of OST in Nairobi, Kenya, at different levels of intervention coverage. We draw on thematic analyses of 109 qualitative interviews with PWID, and 43 with stakeholders, to chart their narratives of expectation in relation to the promise of methadone. Results The modelled impact of OST shows relatively slight reductions in HIV incidence (5–10%) and prevalence (2–4%) over 5 years at coverage levels (around 10%) anticipated in the planned roll-out of OST. However, there is a higher impact with increased coverage, with 40% coverage producing a 20% reduction in HIV incidence, even when accounting for relatively high sexual transmissions. Qualitative findings emphasise a culture of ‘rationed expectation’ in relation to access to care and a ‘poverty of drug treatment opportunity’. In this context, the promise of methadone may be narrated as a symbol of hope—both for individuals and community—in relation to addiction recovery. Conclusions Methadone offers HIV prevention potential, but there is a need to better model the effects of sexual HIV transmission in mediating the impact of OST among PWID in settings characterised by a combination of generalised and concentrated epidemics. We find that individual and community narratives of methadone as hope for recovery coexist with policy narratives positioning methadone primarily in relation to HIV prevention. Our analyses show the value of mixed

  8. PSYCHOLOGY. Estimating the reproducibility of psychological science.

    Science.gov (United States)

    2015-08-28

    Reproducibility is a defining feature of science, but the extent to which it characterizes current research is unknown. We conducted replications of 100 experimental and correlational studies published in three psychology journals using high-powered designs and original materials when available. Replication effects were half the magnitude of original effects, representing a substantial decline. Ninety-seven percent of original studies had statistically significant results. Thirty-six percent of replications had statistically significant results; 47% of original effect sizes were in the 95% confidence interval of the replication effect size; 39% of effects were subjectively rated to have replicated the original result; and if no bias in original results is assumed, combining original and replication results left 68% with statistically significant effects. Correlational tests suggest that replication success was better predicted by the strength of original evidence than by characteristics of the original and replication teams. Copyright © 2015, American Association for the Advancement of Science.

  9. The NANOGrav Observing Program: Automation and Reproducibility

    Science.gov (United States)

    Brazier, Adam; Cordes, James; Demorest, Paul; Dolch, Timothy; Ferdman, Robert; Garver-Daniels, Nathaniel; Hawkins, Steven; Lam, Michael Timothy; Lazio, T. Joseph W.

    2018-01-01

    The NANOGrav Observing Program is a decades-long search for gravitational waves using pulsar timing which relies, for its sensitivity, on large data sets from observations of many pulsars. These are constructed through an intensive, long-term observing campaign. The nature of the program requires automation in the transfer and archiving of the large volume of raw telescope data, the calibration of those data, and making these resulting data products—required for diagnostic and data exploration purposes—available to NANOGrav members. Reproducibility of results is a key goal in this project, and essential to its success; it requires treating the software itself as a data product of the research, while ensuring easy access by, and collaboration between, members of NANOGrav, the International Pulsar Timing Array consortium (of which NANOGrav is a key member), as well as the wider astronomy community and the public.

  10. Uniform and reproducible stirring in a microbioreactor

    DEFF Research Database (Denmark)

    Bolic, Andrijana; Eliasson Lantz, Anna; Rottwitt, Karsten

    At present, research in bioprocess science and engineering increasingly requires fast and accurate analytical data (rapid testing) that can be used for investigation of the interaction between bioprocess operation conditions and the performance of the bioprocess. Miniaturization is certainly...... microbioreactor application. In order to address some of these questions, we are currently investigating and developing a microbioreactor platform with a reactor volume up to 1ml, as we believe that this volume is of interest to many industrial applications. It is widely known that stirring plays a very important...... role in achieving successful cultivations by promoting uniform process conditions and – for aerobic cultivations – a high oxygen transfer rate. In this contribution, the development of a suitable, reliable and reproducible stirrer in a microbioreactor for batch and continuous cultivation of S...

  11. Integrating Qualitative and Quantitative Methods in Participatory Modeling to Elicit Behavioral Drivers in Environmental Dilemmas: the Case of Air Pollution in Talca, Chile.

    Science.gov (United States)

    Meinherz, Franziska; Videira, Nuno

    2018-04-10

    The aim of this paper is to contribute to the exploration of environmental modeling methods based on the elicitation of stakeholders' mental models. This aim is motivated by the necessity to understand the dilemmas and behavioral rationales of individuals for supporting the management of environmental problems. The methodology developed for this paper integrates qualitative and quantitative methods by deploying focus groups for the elicitation of the behavioral rationales of the target population, and grounded theory to code the information gained in the focus groups and to guide the development of a dynamic simulation model. The approach is applied to a case of urban air pollution caused by residential heating with wood in central Chile. The results show how the households' behavior interrelates with the governmental management strategies and provide valuable and novel insights into potential challenges to the implementation of policies to manage the local air pollution problem. The experience further shows that the developed participatory modeling approach allows to overcome some of the issues currently encountered in the elicitation of individuals' behavioral rationales and in the quantification of qualitative information.

  12. Is Grannum grading of the placenta reproducible?

    Science.gov (United States)

    Moran, Mary; Ryan, John; Brennan, Patrick C.; Higgins, Mary; McAuliffe, Fionnuala M.

    2009-02-01

    Current ultrasound assessment of placental calcification relies on Grannum grading. The aim of this study was to assess if this method is reproducible by measuring inter- and intra-observer variation in grading placental images, under strictly controlled viewing conditions. Thirty placental images were acquired and digitally saved. Five experienced sonographers independently graded the images on two separate occasions. In order to eliminate any technological factors which could affect data reliability and consistency all observers reviewed images at the same time. To optimise viewing conditions ambient lighting was maintained between 25-40 lux, with monitors calibrated to the GSDF standard to ensure consistent brightness and contrast. Kappa (κ) analysis of the grades assigned was used to measure inter- and intra-observer reliability. Intra-observer agreement had a moderate mean κ-value of 0.55, with individual comparisons ranging from 0.30 to 0.86. Two images saved from the same patient, during the same scan, were each graded as I, II and III by the same observer. A mean κ-value of 0.30 (range from 0.13 to 0.55) indicated fair inter-observer agreement over the two occasions and only one image was graded consistently the same by all five observers. The study findings confirmed the lack of reproducibility associated with Grannum grading of the placenta despite optimal viewing conditions and highlight the need for new methods of assessing placental health in order to improve neonatal outcomes. Alternative methods for quantifying placental calcification such as a software based technique and 3D ultrasound assessment need to be explored.

  13. Qualitative Economics

    DEFF Research Database (Denmark)

    Fast, Michael; Clark II, Woodrow W

                         This book is about science -- specifically, the science of economics. Or lack thereof is more accurate. The building of any science, let alone economics, is grounded in the understanding of what is beneath the "surface" of economics. Science, and hence economics, should...... be concerned with formulating ideas that express theories which produce descriptions of how to understand phenomenon and real world experiences.                       Economics must become a science, because the essence of economics in terms of human actions, group interactions and communities are in need...... of scientific inquiry. Academics and scholars need a scientific perspective that can hypothesize, theorize document, understand and analyze human dynamics from the individual to more societal interactions. And that is what qualitative economics does; it can make economics into becoming a science. The economic...

  14. The Qualitative Expectations Hypothesis

    DEFF Research Database (Denmark)

    Frydman, Roman; Johansen, Søren; Rahbek, Anders

    2017-01-01

    We introduce the Qualitative Expectations Hypothesis (QEH) as a new approach to modeling macroeconomic and financial outcomes. Building on John Muth's seminal insight underpinning the Rational Expectations Hypothesis (REH), QEH represents the market's forecasts to be consistent with the predictions...... of an economistís model. However, by assuming that outcomes lie within stochastic intervals, QEH, unlike REH, recognizes the ambiguity faced by an economist and market participants alike. Moreover, QEH leaves the model open to ambiguity by not specifying a mechanism determining specific values that outcomes take...

  15. The Qualitative Expectations Hypothesis

    DEFF Research Database (Denmark)

    Frydman, Roman; Johansen, Søren; Rahbek, Anders

    We introduce the Qualitative Expectations Hypothesis (QEH) as a new approach to modeling macroeconomic and financial outcomes. Building on John Muth's seminal insight underpinning the Rational Expectations Hypothesis (REH), QEH represents the market's forecasts to be consistent with the predictions...... of an economist's model. However, by assuming that outcomes lie within stochastic intervals, QEH, unlike REH, recognizes the ambiguity faced by an economist and market participants alike. Moreover, QEH leaves the model open to ambiguity by not specifying a mechanism determining specific values that outcomes take...

  16. Evaluation of Statistical Downscaling Skill at Reproducing Extreme Events

    Science.gov (United States)

    McGinnis, S. A.; Tye, M. R.; Nychka, D. W.; Mearns, L. O.

    2015-12-01

    Climate model outputs usually have much coarser spatial resolution than is needed by impacts models. Although higher resolution can be achieved using regional climate models for dynamical downscaling, further downscaling is often required. The final resolution gap is often closed with a combination of spatial interpolation and bias correction, which constitutes a form of statistical downscaling. We use this technique to downscale regional climate model data and evaluate its skill in reproducing extreme events. We downscale output from the North American Regional Climate Change Assessment Program (NARCCAP) dataset from its native 50-km spatial resolution to the 4-km resolution of University of Idaho's METDATA gridded surface meterological dataset, which derives from the PRISM and NLDAS-2 observational datasets. We operate on the major variables used in impacts analysis at a daily timescale: daily minimum and maximum temperature, precipitation, humidity, pressure, solar radiation, and winds. To interpolate the data, we use the patch recovery method from the Earth System Modeling Framework (ESMF) regridding package. We then bias correct the data using Kernel Density Distribution Mapping (KDDM), which has been shown to exhibit superior overall performance across multiple metrics. Finally, we evaluate the skill of this technique in reproducing extreme events by comparing raw and downscaled output with meterological station data in different bioclimatic regions according to the the skill scores defined by Perkins et al in 2013 for evaluation of AR4 climate models. We also investigate techniques for improving bias correction of values in the tails of the distributions. These techniques include binned kernel density estimation, logspline kernel density estimation, and transfer functions constructed by fitting the tails with a generalized pareto distribution.

  17. Response to Comment on "Estimating the reproducibility of psychological science"

    NARCIS (Netherlands)

    Anderson, Christopher J; Bahník, Štěpán; Barnett-Cowan, Michael; Bosco, Frank A; Chandler, Jesse; Chartier, Christopher R; Cheung, Felix; Christopherson, Cody D; Cordes, Andreas; Cremata, Edward J; Della Penna, Nicolas; Estel, Vivien; Fedor, Anna; Fitneva, Stanka A; Frank, Michael C; Grange, James A; Hartshorne, Joshua K; Hasselman, Fred; Henninger, Felix; van der Hulst, Marije; Jonas, Kai J; Lai, Calvin K; Levitan, Carmel A; Miller, Jeremy K; Moore, Katherine S; Meixner, Johannes M; Munafò, Marcus R; Neijenhuijs, Koen I; Nilsonne, Gustav; Nosek, Brian A; Plessow, Franziska; Prenoveau, Jason M; Ricker, Ashley A; Schmidt, Kathleen; Spies, Jeffrey R; Stieger, Stefan; Strohminger, Nina; Sullivan, Gavin B; van Aert, Robbie C M; van Assen, Marcel A L M; Vanpaemel, Wolf; Vianello, Michelangelo; Voracek, Martin; Zuni, Kellylynn

    2016-01-01

    Gilbert et al. conclude that evidence from the Open Science Collaboration's Reproducibility Project: Psychology indicates high reproducibility, given the study methodology. Their very optimistic assessment is limited by statistical misconceptions and by causal inferences from selectively

  18. Qualitative and simultaneous quantitative analysis of cimetidine polymorphs by ultraviolet-visible and shortwave near-infrared diffuse reflectance spectroscopy and multivariate calibration models.

    Science.gov (United States)

    Feng, Yuyan; Li, Xiangling; Xu, Kailin; Zou, Huayu; Li, Hui; Liang, Bing

    2015-02-01

    The object of the present study was to investigate the feasibility of applying ultraviolet-visible and shortwave near-infrared diffuse reflectance spectroscopy (UV-vis-SWNIR DRS) coupled with chemometrics in qualitative and simultaneous quantitative analysis of drug polymorphs, using cimetidine as a model drug. Three polymorphic forms (A, B and D) and a mixed crystal (M1) of cimetidine, obtained by preparation under different crystallization conditions, were characterized by microscopy, X-ray powder diffraction (XRPD) and infrared spectroscopy (IR). The discriminant models of four forms (A, B, D and M1) were established by discriminant partial least squares (PLS-DA) using different pretreated spectra. The R and RMSEP of samples in the prediction set by discriminant model with original spectra were 0.9959 and 0.1004. Among the quantitative models of binary mixtures (A and D) established by partial least squares (PLS) and least squares-support vector machine (LS-SVM) with different pretreated spectra, the LS-SVM models based on original and MSC spectra had better prediction effect with a R of 1.0000 and a RMSEP of 0.0134 for form A, and a R of 1.0000 and a RMSEP of 0.0024 for form D. For ternary mixtures, the established PLS quantitative models based on normalized spectra had relatively better prediction effect for forms A, B and D with R of 0.9901, 0.9820 and 0.9794 and RMSEP of 0.0471, 0.0529 and 0.0594, respectively. This research indicated that UV-vis-SWNIR DRS can be used as a simple, rapid, nondestructive qualitative and quantitative method for the analysis of drug polymorphs. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. Role Models and Teachers: medical students perception of teaching-learning methods in clinical settings, a qualitative study from Sri Lanka.

    Science.gov (United States)

    Jayasuriya-Illesinghe, Vathsala; Nazeer, Ishra; Athauda, Lathika; Perera, Jennifer

    2016-02-09

    Medical education research in general, and those focusing on clinical settings in particular, have been a low priority in South Asia. This explorative study from 3 medical schools in Sri Lanka, a South Asian country, describes undergraduate medical students' experiences during their final year clinical training with the aim of understanding the teaching-learning experiences. Using qualitative methods we conducted an exploratory study. Twenty eight graduates from 3 medical schools participated in individual interviews. Interview recordings were transcribed verbatim and analyzed using qualitative content analysis method. Emergent themes reveled 2 types of teaching-learning experiences, role modeling, and purposive teaching. In role modelling, students were expected to observe teachers while they conduct their clinical work, however, this method failed to create positive learning experiences. The clinical teachers who predominantly used this method appeared to be 'figurative' role models and were not perceived as modelling professional behaviors. In contrast, purposeful teaching allowed dedicated time for teacher-student interactions and teachers who created these learning experiences were more likely to be seen as 'true' role models. Students' responses and reciprocations to these interactions were influenced by their perception of teachers' behaviors, attitudes, and the type of teaching-learning situations created for them. Making a distinction between role modeling and purposeful teaching is important for students in clinical training settings. Clinical teachers' awareness of their own manifest professional characterizes, attitudes, and behaviors, could help create better teaching-learning experiences. Moreover, broader systemic reforms are needed to address the prevailing culture of teaching by humiliation and subordination.

  20. Reliability: on the reproducibility of assessment data.

    Science.gov (United States)

    Downing, Steven M

    2004-09-01

    All assessment data, like other scientific experimental data, must be reproducible in order to be meaningfully interpreted. The purpose of this paper is to discuss applications of reliability to the most common assessment methods in medical education. Typical methods of estimating reliability are discussed intuitively and non-mathematically. Reliability refers to the consistency of assessment outcomes. The exact type of consistency of greatest interest depends on the type of assessment, its purpose and the consequential use of the data. Written tests of cognitive achievement look to internal test consistency, using estimation methods derived from the test-retest design. Rater-based assessment data, such as ratings of clinical performance on the wards, require interrater consistency or agreement. Objective structured clinical examinations, simulated patient examinations and other performance-type assessments generally require generalisability theory analysis to account for various sources of measurement error in complex designs and to estimate the consistency of the generalisations to a universe or domain of skills. Reliability is a major source of validity evidence for assessments. Low reliability indicates that large variations in scores can be expected upon retesting. Inconsistent assessment scores are difficult or impossible to interpret meaningfully and thus reduce validity evidence. Reliability coefficients allow the quantification and estimation of the random errors of measurement in assessments, such that overall assessment can be improved.

  1. Environment and industrial economy: Challenge of reproducibility

    International Nuclear Information System (INIS)

    Rullani, E.

    1992-01-01

    Historically and methodologically counterposed until now, the environmentalist and the economic approach to environmental problems need to be integrated in a new approach that considers, from one side, the relevance of the ecological equilibria for the economic systems and, from the other side, the economic dimension (in terms of investments and transformations in the production system) of any attempt to achieve a better environment. In order to achieve this integration, both approaches are compelled to give up some cultural habits that have characterized them, and have contributed to over-emphasize the opposition between them. The article shows that both approaches can converge into a new one, in which environment is no longer only an holistic, not bargainable, natural external limit to human activity (as in the environmentalist approach), nor simply a scarce and exhaustible resource (as economics tends to consider it); environment should instead become part of the reproducibility sphere, or, in other words, it must be regarded as part of the output that the economic system provides. This new approach, due to scientific and technological advances, is made possible for an increasing class of environmental problems. In order to do this, an evolution is required, that could be able to convert environmental goals into investment and technological innovation goals, and communicate to the firms the value society assigns to environmental resources. This value, the author suggests, should correspond to the reproduction cost. Various examples of this new approach are analyzed and discussed

  2. Reproducibility of neuroimaging analyses across operating systems.

    Science.gov (United States)

    Glatard, Tristan; Lewis, Lindsay B; Ferreira da Silva, Rafael; Adalat, Reza; Beck, Natacha; Lepage, Claude; Rioux, Pierre; Rousseau, Marc-Etienne; Sherif, Tarek; Deelman, Ewa; Khalili-Mahani, Najmeh; Evans, Alan C

    2015-01-01

    Neuroimaging pipelines are known to generate different results depending on the computing platform where they are compiled and executed. We quantify these differences for brain tissue classification, fMRI analysis, and cortical thickness (CT) extraction, using three of the main neuroimaging packages (FSL, Freesurfer and CIVET) and different versions of GNU/Linux. We also identify some causes of these differences using library and system call interception. We find that these packages use mathematical functions based on single-precision floating-point arithmetic whose implementations in operating systems continue to evolve. While these differences have little or no impact on simple analysis pipelines such as brain extraction and cortical tissue classification, their accumulation creates important differences in longer pipelines such as subcortical tissue classification, fMRI analysis, and cortical thickness extraction. With FSL, most Dice coefficients between subcortical classifications obtained on different operating systems remain above 0.9, but values as low as 0.59 are observed. Independent component analyses (ICA) of fMRI data differ between operating systems in one third of the tested subjects, due to differences in motion correction. With Freesurfer and CIVET, in some brain regions we find an effect of build or operating system on cortical thickness. A first step to correct these reproducibility issues would be to use more precise representations of floating-point numbers in the critical sections of the pipelines. The numerical stability of pipelines should also be reviewed.

  3. Reproducibility of the water drinking test.

    Science.gov (United States)

    Muñoz, C R; Macias, J H; Hartleben, C

    2015-11-01

    To investigate the reproducibility of the water drinking test in determining intraocular pressure peaks and fluctuation. It has been suggested that there is limited agreement between the water drinking test and diurnal tension curve. This may be because it has only been compared with a 10-hour modified diurnal tension curve, missing 70% of IOP peaks that occurred during night. This was a prospective, analytical and comparative study that assesses the correlation, agreement, sensitivity and specificity of the water drinking test. The correlation between the water drinking test and diurnal tension curve was significant and strong (r=0.93, Confidence interval 95% between 0.79 and 0.96, p<01). A moderate agreement was observed between these measurements (pc=0.93, Confidence interval 95% between 0.87 and 0.95, p<.01). The agreement was within±2mmHg in 89% of the tests. Our study found a moderate agreement between the water drinking test and diurnal tension curve, in contrast with the poor agreement found in other studies, possibly due to the absence of nocturnal IOP peaks. These findings suggest that the water drinking test could be used to determine IOP peaks, as well as for determining baseline IOP. Copyright © 2014 Sociedad Española de Oftalmología. Published by Elsevier España, S.L.U. All rights reserved.

  4. Are classifications of proximal radius fractures reproducible?

    Directory of Open Access Journals (Sweden)

    dos Santos João BG

    2009-10-01

    Full Text Available Abstract Background Fractures of the proximal radius need to be classified in an appropriate and reproducible manner. The aim of this study was to assess the reliability of the three most widely used classification systems. Methods Elbow radiographs images of patients with proximal radius fractures were classified according to Mason, Morrey, and Arbeitsgemeinschaft für osteosynthesefragen/Association for the Study of Internal Fixation (AO/ASIF classifications by four observers with different experience with this subject to assess their intra- and inter-observer agreement. Each observer analyzed the images on three different occasions on a computer with numerical sequence randomly altered. Results We found that intra-observer agreement of Mason and Morrey classifications were satisfactory (κ = 0.582 and 0.554, respectively, while the AO/ASIF classification had poor intra-observer agreement (κ = 0.483. Inter-observer agreement was higher in the Mason (κ = 0.429-0.560 and Morrey (κ = 0.319-0.487 classifications than in the AO/ASIF classification (κ = 0.250-0.478, which showed poor reliability. Conclusion Inter- and intra-observer agreement of the Mason and Morey classifications showed overall satisfactory reliability when compared to the AO/ASIF system. The Mason classification is the most reliable system.

  5. Ratio-scaling of listener preference of multichannel reproduced sound

    DEFF Research Database (Denmark)

    Choisel, Sylvain; Wickelmaier, Florian

    2005-01-01

    -trivial assumption in the case of complex spatial sounds. In the present study the Bradley-Terry-Luce (BTL) model was employed to investigate the unidimensionality of preference judgments made by 40 listeners on multichannel reproduced sound. Short musical excerpts played back in eight reproduction modes (mono......, stereo and various multichannel formats) served as stimuli. On each trial, the task of the subjects was to choose the format they preferred, proceeding through all the possible pairs of the eight reproduction modes. This experiment was replicated with four types of programme material (pop and classical...... music). As a main result, the BTL model was found to predict the choice frequencies well. This implies that listeners were able to integrate the complex nature of the sounds into a unidimensional preference judgment. It further implies the existence of a preference scale on which the reproduction modes...

  6. Illusory Motion Reproduced by Deep Neural Networks Trained for Prediction

    Directory of Open Access Journals (Sweden)

    Eiji Watanabe

    2018-03-01

    Full Text Available The cerebral cortex predicts visual motion to adapt human behavior to surrounding objects moving in real time. Although the underlying mechanisms are still unknown, predictive coding is one of the leading theories. Predictive coding assumes that the brain's internal models (which are acquired through learning predict the visual world at all times and that errors between the prediction and the actual sensory input further refine the internal models. In the past year, deep neural networks based on predictive coding were reported for a video prediction machine called PredNet. If the theory substantially reproduces the visual information processing of the cerebral cortex, then PredNet can be expected to represent the human visual perception of motion. In this study, PredNet was trained with natural scene videos of the self-motion of the viewer, and the motion prediction ability of the obtained computer model was verified using unlearned videos. We found that the computer model accurately predicted the magnitude and direction of motion of a rotating propeller in unlearned videos. Surprisingly, it also represented the rotational motion for illusion images that were not moving physically, much like human visual perception. While the trained network accurately reproduced the direction of illusory rotation, it did not detect motion components in negative control pictures wherein people do not perceive illusory motion. This research supports the exciting idea that the mechanism assumed by the predictive coding theory is one of basis of motion illusion generation. Using sensory illusions as indicators of human perception, deep neural networks are expected to contribute significantly to the development of brain research.

  7. Time-lapse deselection model for human day 3 in vitro fertilization embryos: the combination of qualitative and quantitative measures of embryo growth.

    Science.gov (United States)

    Liu, Yanhe; Chapple, Vincent; Feenan, Katie; Roberts, Peter; Matson, Phillip

    2016-03-01

    To present a time-lapse deselection model involving both qualitative and quantitative parameters for assessing embryos on day 3. Retrospective cohort study and prospective validation. Private IVF center. A total of 270 embryos with known implantation data (KID) after day 3 transfer from 212 IVF/intracytoplasmic sperm injection (ICSI) cycles were retrospectively analyzed for building the proposed deselection model, followed by prospective validation using an additional 66 KID embryos. None. Morphological score on day 3, embryo morphokinetic parameters, abnormal cleavage patterns, and known implantation results. All included embryos were categorized either retrospectively or prospectively into 7 grades (A+, A, B, C, D, E, F). Qualitative deselection parameters included poor conventional day 3 morphology, abnormal cleavage patterns identified via time-lapse monitoring, and deselection effectively predicts day 3 embryo implantation potential and is applicable to all IVF embryos regardless of insemination method by using PNF as the reference starting time point. Copyright © 2016 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  8. Can learning by qualitative modelling be deployed as an effective method for learning subject-specific content?

    NARCIS (Netherlands)

    Schlatter, E.; Bredeweg, B.; Drie, J.P. van; Jong, P.F. de

    2017-01-01

    Modelling can help understanding dynamic systems, but learning how to model is a difficult and time-consuming task. The challenge is to foster modelling skills, while not limiting the learning of regular subject matter, or better, to also improve this learning. We investigate how learning by

  9. A Qualitative Study of Motivation to Read for Pleasure with Adolescent Struggling Readers Using a Theoretical Model: How to Begin?

    Science.gov (United States)

    Fisher, Gary A.

    2013-01-01

    A mixed method study explored a theoretical model that employed, combined, and added to the theories of self-determination, the reading engagement perspective, and the four-phase model of interest to motivate adolescent struggling readers to read for pleasure. The model adds to the existing body of research because it specifies an instructional…

  10. Towards personalized integrated dementia care: a qualitative study into the implementation of different models of case management

    NARCIS (Netherlands)

    van Mierlo, L.D.; Meiland, F.J.M.; van Hout, H.P.J.; Dröes, R.M.

    2014-01-01

    Background: The aim of this process evaluation was to provide insight into facilitators and barriers to the delivery of community-based personalized dementia care of two different case management models, i.e. the linkage model and the combined intensive case management/joint agency model. These two

  11. Reproducibility of adenosine stress cardiovascular magnetic resonance in multi-vessel symptomatic coronary artery disease

    Directory of Open Access Journals (Sweden)

    Feneley Michael P

    2010-07-01

    Full Text Available Abstract Purpose First-pass perfusion cardiovascular magnetic resonance (CMR is increasingly being utilized in both clinical practice and research. However, the reproducibility of this technique remains incompletely evaluated, particularly in patients with severe coronary artery disease (CAD. The purpose of this study was to determine the inter-study reproducibility of adenosine stress CMR in patients with symptomatic multi-vessel CAD and those at low risk for CAD. Methods Twenty patients (10 with CAD, 10 low risk CAD underwent two CMR scans 8 ± 2 days apart. Basal, mid and apical left ventricular short axis slices were acquired using gadolinium 0.05 mmol/kg at peak stress (adenosine, 140 μ/kg/min, 4 min and rest. Myocardial perfusion was evaluated qualitatively by assessing the number of ischemic segments, and semi-quantitatively by determining the myocardial perfusion reserve index (MPRi using a normalized upslope method. Inter-study and observer reproducibility were assessed--the latter being defined by the coefficient of variation (CoV, which was calculated from the standard deviation of the differences of the measurements, divided by the mean. Additionally, the percentage of myocardial segments with perfect agreement and inter- and intra-observer MPRi correlation between studies, were also determined. Results The CoV for the number of ischemic segments was 31% with a mean difference of -0.15 ± 0.88 segments and 91% perfect agreement between studies. MPRi was lower in patients with CAD (1.13 ± 0.21 compared to those with low risk CAD (1.59 ± 0.58, p = 0.02. The reproducibility of MPRi was 19% with no significant difference between patients with CAD and those with low risk CAD (p = 0.850. Observer reproducibility for MPRi was high: inter-observer CoV 9%, r = 0.93 and intra-observer CoV 5%, r = 0.94. For trials using perfusion CMR as an endpoint, an estimated sample size of 12 subjects would be required to detect a two-segment change in

  12. A systematic review and qualitative analysis to inform the development of a new emergency department-based geriatric case management model.

    Science.gov (United States)

    Sinha, Samir K; Bessman, Edward S; Flomenbaum, Neal; Leff, Bruce

    2011-06-01

    We inform the future development of a new geriatric emergency management practice model. We perform a systematic review of the existing evidence for emergency department (ED)-based case management models designed to improve the health, social, and health service utilization outcomes for noninstitutionalized older patients within the context of an index ED visit. This was a systematic review of English-language articles indexed in MEDLINE and CINAHL (1966 to 2010), describing ED-based case management models for older adults. Bibliographies of the retrieved articles were reviewed to identify additional references. A systematic qualitative case study analytic approach was used to identify the core operational components and outcome measures of the described clinical interventions. The authors of the included studies were also invited to verify our interpretations of their work. The determined patterns of component adherence were then used to postulate the relative importance and effect of the presence or absence of a particular component in influencing the overall effectiveness of their respective interventions. Eighteen of 352 studies (reported in 20 articles) met study criteria. Qualitative analyses identified 28 outcome measures and 8 distinct model characteristic components that included having an evidence-based practice model, nursing clinical involvement or leadership, high-risk screening processes, focused geriatric assessments, the initiation of care and disposition planning in the ED, interprofessional and capacity-building work practices, post-ED discharge follow-up with patients, and evaluation and monitoring processes. Of the 15 positive study results, 6 had all 8 characteristic components and 9 were found to be lacking at least 1 component. Two studies with positive results lacked 2 characteristic components and none lacked more than 2 components. Of the 3 studies with negative results demonstrating no positive effects based on any outcome tested, one

  13. EXPERTS 1—experiences of long-term life-limiting conditions among patients and carers: protocol for a qualitative meta-synthesis and conceptual modelling study

    Science.gov (United States)

    May, Carl R; Masters, Jayne; Welch, Lindsay; Hunt, Katherine; Pope, Catherine; Myall, Michelle; Griffiths, Peter; Roderick, Paul; Glanville, Julie; Richardson, Alison

    2015-01-01

    Introduction Increasing numbers of the population are living with long-term life-limiting conditions with a significant proportion characterised by multimorbidity. Patients with these conditions often experience high volumes of clinical interaction involving them, their caregivers and healthcare providers in complex patterns of organising, coordinating, negotiating and managing care. A better understanding of the sources of experienced complexity and multimorbidity, from the patient perspective is paramount to improve capacity and manage workload to promote improved experience of illness, more effective healthcare utilisation and improved healthcare outcomes. To better understand the sources of complexity we will undertake an evidence synthesis of qualitative studies of patient and informal carer experiences of three common long-term life-limiting conditions. We will investigate what is known about these diseases at different stages in disease progression, treatment regimens and places of care. Method and analysis We will include qualitative studies of patients’ and carers’ (aged >18) accounts of their experiences of healthcare provision in a range of settings and healthcare systems. We will conduct an extensive electronic database search of publications in English between 2000 and 2014. Results and discussions sections of the papers will be regarded as formal data using the constant comparison method of qualitative analysis. From the meta-synthesis results, we will build a conceptual model of mechanisms and processes that shape patients’ journeys towards end of life to suggest where in the patient journey new interventions to improve patient and carer experience can be developed and delivered. The study is being conducted between 1 December 2014 and 31 December 2015. Ethics and dissemination No human subjects or personal data are involved and no ethical issues are anticipated. An important element of dissemination is informing user communities about the

  14. Qualitative and quantitative analysis of the students’ perceptions to the use of 3D electronic models in problem-based learning

    Directory of Open Access Journals (Sweden)

    Hai Ming Wong

    2017-06-01

    Full Text Available Faculty of Dentistry of the University of Hong Kong has introduced innovative blended problem-based learning (PBL with the aid of 3D electronic models (e-models to Bachelor of Dental Surgery (BDS curriculum. Statistical results of pre- and post-semester questionnaire surveys illustrated compatibility of e-models in PBL settings. The students’ importance ratings of two objectives “Complete assigned tasks on time” and “Active listener”, and twenty-two facilitator evaluation items including critical thinking and group problem-solving skills had increased significantly. The students’ PBL preparation behavior, attentions to problem understanding, problem analysis, and learning resource quality were also found to be related to online support of e-models and its software. Qualitative analysis of open-ended questions with visual text analytic software “Leximancer” improved validity of statistical results. Using e-model functions in treatment planning, problem analysis and giving instructions provided a method of informative communication. Therefore, it is critical for the faculty to continuously provide facilitator training and quality online e-model resources to the students.

  15. Is the promise of methadone Kenya's solution to managing HIV and addiction? A mixed-method mathematical modelling and qualitative study.

    Science.gov (United States)

    Rhodes, Tim; Guise, Andy; Ndimbii, James; Strathdee, Steffanie; Ngugi, Elizabeth; Platt, Lucy; Kurth, Ann; Cleland, Charles; Vickerman, Peter

    2015-03-06

    Promoted globally as an evidence-based intervention in the prevention of HIV and treatment of heroin addiction among people who inject drugs (PWID), opioid substitution treatment (OST) can help control emerging HIV epidemics among PWID. With implementation in December 2014, Kenya is the third Sub-Saharan African country to have introduced OST. We combine dynamic mathematical modelling with qualitative sociological research to examine the 'promise of methadone' to Kenya. We model the HIV prevention impact of OST in Nairobi, Kenya, at different levels of intervention coverage. We draw on thematic analyses of 109 qualitative interviews with PWID, and 43 with stakeholders, to chart their narratives of expectation in relation to the promise of methadone. The modelled impact of OST shows relatively slight reductions in HIV incidence (5-10%) and prevalence (2-4%) over 5 years at coverage levels (around 10%) anticipated in the planned roll-out of OST. However, there is a higher impact with increased coverage, with 40% coverage producing a 20% reduction in HIV incidence, even when accounting for relatively high sexual transmissions. Qualitative findings emphasise a culture of 'rationed expectation' in relation to access to care and a 'poverty of drug treatment opportunity'. In this context, the promise of methadone may be narrated as a symbol of hope-both for individuals and community-in relation to addiction recovery. Methadone offers HIV prevention potential, but there is a need to better model the effects of sexual HIV transmission in mediating the impact of OST among PWID in settings characterised by a combination of generalised and concentrated epidemics. We find that individual and community narratives of methadone as hope for recovery coexist with policy narratives positioning methadone primarily in relation to HIV prevention. Our analyses show the value of mixed methods approaches to investigating newly-introduced interventions. Published by the BMJ Publishing

  16. GeoTrust Hub: A Platform For Sharing And Reproducing Geoscience Applications

    Science.gov (United States)

    Malik, T.; Tarboton, D. G.; Goodall, J. L.; Choi, E.; Bhatt, A.; Peckham, S. D.; Foster, I.; Ton That, D. H.; Essawy, B.; Yuan, Z.; Dash, P. K.; Fils, G.; Gan, T.; Fadugba, O. I.; Saxena, A.; Valentic, T. A.

    2017-12-01

    Recent requirements of scholarly communication emphasize the reproducibility of scientific claims. Text-based research papers are considered poor mediums to establish reproducibility. Papers must be accompanied by "research objects", aggregation of digital artifacts that together with the paper provide an authoritative record of a piece of research. We will present GeoTrust Hub (http://geotrusthub.org), a platform for creating, sharing, and reproducing reusable research objects. GeoTrust Hub provides tools for scientists to create `geounits'--reusable research objects. Geounits are self-contained, annotated, and versioned containers that describe and package computational experiments in an efficient and light-weight manner. Geounits can be shared on public repositories such as HydroShare and FigShare, and also using their respective APIs reproduced on provisioned clouds. The latter feature enables science applications to have a lifetime beyond sharing, wherein they can be independently verified and trust be established as they are repeatedly reused. Through research use cases from several geoscience laboratories across the United States, we will demonstrate how tools provided from GeoTrust Hub along with Hydroshare as its public repository for geounits is advancing the state of reproducible research in the geosciences. For each use case, we will address different computational reproducibility requirements. Our first use case will be an example of setup reproducibility which enables a scientist to set up and reproduce an output from a model with complex configuration and development environments. Our second use case will be an example of algorithm/data reproducibility, where in a shared data science model/dataset can be substituted with an alternate one to verify model output results, and finally an example of interactive reproducibility, in which an experiment is dependent on specific versions of data to produce the result. Toward this we will use software and data

  17. Semiautomated, Reproducible Batch Processing of Soy

    Science.gov (United States)

    Thoerne, Mary; Byford, Ivan W.; Chastain, Jack W.; Swango, Beverly E.

    2005-01-01

    A computer-controlled apparatus processes batches of soybeans into one or more of a variety of food products, under conditions that can be chosen by the user and reproduced from batch to batch. Examples of products include soy milk, tofu, okara (an insoluble protein and fiber byproduct of soy milk), and whey. Most processing steps take place without intervention by the user. This apparatus was developed for use in research on processing of soy. It is also a prototype of other soy-processing apparatuses for research, industrial, and home use. Prior soy-processing equipment includes household devices that automatically produce soy milk but do not automatically produce tofu. The designs of prior soy-processing equipment require users to manually transfer intermediate solid soy products and to press them manually and, hence, under conditions that are not consistent from batch to batch. Prior designs do not afford choices of processing conditions: Users cannot use previously developed soy-processing equipment to investigate the effects of variations of techniques used to produce soy milk (e.g., cold grinding, hot grinding, and pre-cook blanching) and of such process parameters as cooking times and temperatures, grinding times, soaking times and temperatures, rinsing conditions, and sizes of particles generated by grinding. In contrast, the present apparatus is amenable to such investigations. The apparatus (see figure) includes a processing tank and a jacketed holding or coagulation tank. The processing tank can be capped by either of two different heads and can contain either of two different insertable mesh baskets. The first head includes a grinding blade and heating elements. The second head includes an automated press piston. One mesh basket, designated the okara basket, has oblong holes with a size equivalent to about 40 mesh [40 openings per inch (.16 openings per centimeter)]. The second mesh basket, designated the tofu basket, has holes of 70 mesh [70 openings

  18. Precision and reproducibility in AMS radiocarbon measurements.

    Energy Technology Data Exchange (ETDEWEB)

    Hotchkis, M.A.; Fink, D.; Hua, Q.; Jacobsen, G.E.; Lawson, E. M.; Smith, A.M.; Tuniz, C. [Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW (Australia)

    1996-12-31

    Accelerator Mass Spectrometry (AMS) is a technique by which rare radioisotopes such as {sup 14}C can be measured at environmental levels with high efficiency. Instead of detecting radioactivity, which is very weak for long-lived environmental radioisotopes, atoms are counted directly. The sample is placed in an ion source, from which a negative ion beam of the atoms of interest is extracted, mass analysed, and injected into a tandem accelerator. After stripping to positive charge states in the accelerator HV terminal, the ions are further accelerated, analysed with magnetic and electrostatic devices and counted in a detector. An isotopic ratio is derived from the number of radioisotope atoms counted in a given time and the beam current of a stable isotope of the same element, measured after the accelerator. For radiocarbon, {sup 14}C/{sup 13}C ratios are usually measured, and the ratio of an unknown sample is compared to that of a standard. The achievable precision for such ratio measurements is limited primarily by {sup 14}C counting statistics and also by a variety of factors related to accelerator and ion source stability. At the ANTARES AMS facility at Lucas Heights Research Laboratories we are currently able to measure {sup 14}C with 0.5% precision. In the two years since becoming operational, more than 1000 {sup 14}C samples have been measured. Recent improvements in precision for {sup 14}C have been achieved with the commissioning of a 59 sample ion source. The measurement system, from sample changing to data acquisition, is under common computer control. These developments have allowed a new regime of automated multi-sample processing which has impacted both on the system throughput and the measurement precision. We have developed data evaluation methods at ANTARES which cross-check the self-consistency of the statistical analysis of our data. Rigorous data evaluation is invaluable in assessing the true reproducibility of the measurement system and aids in

  19. Quark/gluon jet discrimination: a reproducible analysis using R

    CERN Multimedia

    CERN. Geneva

    2017-01-01

    The power to discriminate between light-quark jets and gluon jets would have a huge impact on many searches for new physics at CERN and beyond. This talk will present a walk-through of the development of a prototype machine learning classifier for differentiating between quark and gluon jets at experiments like those at the Large Hadron Collider at CERN. A new fast feature selection method that combines information theory and graph analytics will be outlined. This method has found new variables that promise significant improvements in discrimination power. The prototype jet tagger is simple, interpretable, parsimonious, and computationally extremely cheap, and therefore might be suitable for use in trigger systems for real-time data processing. Nested stratified k-fold cross validation was used to generate robust estimates of model performance. The data analysis was performed entirely in the R statistical programming language, and is fully reproducible. The entire analysis workflow is data-driven, automated a...

  20. Reproducing an extreme flood with uncertain post-event information

    Directory of Open Access Journals (Sweden)

    D. Fuentes-Andino

    2017-07-01

    Full Text Available Studies for the prevention and mitigation of floods require information on discharge and extent of inundation, commonly unavailable or uncertain, especially during extreme events. This study was initiated by the devastating flood in Tegucigalpa, the capital of Honduras, when Hurricane Mitch struck the city. In this study we hypothesized that it is possible to estimate, in a trustworthy way considering large data uncertainties, this extreme 1998 flood discharge and the extent of the inundations that followed from a combination of models and post-event measured data. Post-event data collected in 2000 and 2001 were used to estimate discharge peaks, times of peak, and high-water marks. These data were used in combination with rain data from two gauges to drive and constrain a combination of well-known modelling tools: TOPMODEL, Muskingum–Cunge–Todini routing, and the LISFLOOD-FP hydraulic model. Simulations were performed within the generalized likelihood uncertainty estimation (GLUE uncertainty-analysis framework. The model combination predicted peak discharge, times of peaks, and more than 90 % of the observed high-water marks within the uncertainty bounds of the evaluation data. This allowed an inundation likelihood map to be produced. Observed high-water marks could not be reproduced at a few locations on the floodplain. Identifications of these locations are useful to improve model set-up, model structure, or post-event data-estimation methods. Rainfall data were of central importance in simulating the times of peak and results would be improved by a better spatial assessment of rainfall, e.g. from radar data or a denser rain-gauge network. Our study demonstrated that it was possible, considering the uncertainty in the post-event data, to reasonably reproduce the extreme Mitch flood in Tegucigalpa in spite of no hydrometric gauging during the event. The method proposed here can be part of a Bayesian framework in which more events

  1. Sustainability of a community-based anti-retroviral care delivery model - a qualitative research study in Tete, Mozambique.

    Science.gov (United States)

    Rasschaert, Freya; Decroo, Tom; Remartinez, Daniel; Telfer, Barbara; Lessitala, Faustino; Biot, Marc; Candrinho, Baltazar; Van Damme, Wim

    2014-01-01

    To overcome patients' reported barriers to accessing anti-retroviral therapy (ART), a community-based delivery model was piloted in Tete, Mozambique. Community ART Groups (CAGs) of maximum six patients stable on ART offered cost- and time-saving benefits and mutual psychosocial support, which resulted in better adherence and retention outcomes. To date, Médecins Sans Frontières has coordinated and supported these community-driven activities. To better understand the sustainability of the CAG model, we developed a conceptual framework on sustainability of community-based programmes. This was used to explore the data retrieved from 16 focus group discussions and 24 in-depth interviews with different stakeholder groups involved in the CAG model and to identify factors influencing the sustainability of the CAG model. We report the findings according to the framework's five components. (1) The CAG model was designed to overcome patients' barriers to ART and was built on a concept of self-management and patient empowerment to reach effective results. (2) Despite the progressive Ministry of Health (MoH) involvement, the daily management of the model is still strongly dependent on external resources, especially the need for a regulatory cadre to form and monitor the groups. These additional resources are in contrast to the limited MoH resources available. (3) The model is strongly embedded in the community, with patients taking a more active role in their own healthcare and that of their peers. They are considered as partners in healthcare, which implies a new healthcare approach. (4) There is a growing enabling environment with political will and general acceptance to support the CAG model. (5) However, contextual factors, such as poverty, illiteracy and the weak health system, influence the community-based model and need to be addressed. The community embeddedness of the model, together with patient empowerment, high acceptability and progressive MoH involvement

  2. On the Inclusion Relation of Reproducing Kernel Hilbert Spaces

    OpenAIRE

    Zhang, Haizhang; Zhao, Liang

    2011-01-01

    To help understand various reproducing kernels used in applied sciences, we investigate the inclusion relation of two reproducing kernel Hilbert spaces. Characterizations in terms of feature maps of the corresponding reproducing kernels are established. A full table of inclusion relations among widely-used translation invariant kernels is given. Concrete examples for Hilbert-Schmidt kernels are presented as well. We also discuss the preservation of such a relation under various operations of ...

  3. Qualitative feature extractions of chaotic systems

    International Nuclear Information System (INIS)

    Vicha, T.; Dohnal, M.

    2008-01-01

    The theory of chaos offers useful tools for systems analysis. However, models of complex systems are based on a network of inconsistent, space and uncertain knowledge items. Traditional quantitative methods of chaos analysis are therefore not applicable. The paper by the same authors [Vicha T, Dohnal M. Qualitative identification of chaotic systems behaviours. Chaos, Solitons and Fractals, in press, [Log. No. 601019] ] presents qualitative interpretation of some chaos concepts. There are only three qualitative values positive/increasing, negative/decreasing and zero/constant. It means that any set of qualitative multidimensional descriptions of unsteady state behaviours is discrete and finite. A finite upper limit exists for the total number of qualitatively distinguishable scenarios. A set of 21 published chaotic models is solved qualitatively and 21 sets of all existing qualitative scenarios are presented. The intersection of all 21 scenario sets is empty. There is no such a behaviour which is common for all 21 models. The set of 21 qualitative models (e.g. Lorenz, Roessler) can be used to compare chaotic behaviours of an unknown qualitative model with them to evaluate if its chaotic behaviours is close to e.g. Lorenz chaotic model and how much

  4. A Conceptual Model of Dyadic Coordination in HIV Care Engagement Among Couples of Black Men Who Have Sex with Men: A Qualitative Dyadic Analysis.

    Science.gov (United States)

    Tan, Judy Y; Campbell, Chadwick K; Tabrisky, Alyssa P; Siedle-Khan, Robert; Conroy, Amy A

    2018-02-20

    Among Black men who have sex with men (MSM), HIV incidence is disproportionately high and HIV care engagement is disproportionately low. There may be important opportunities to leverage the primary relationship to improve engagement in HIV care and treatment among Black MSM couples. Using dyadic qualitative analysis of semi-structured, one-on-one interviews, we explored dyadic aspects of HIV care engagement among 14 Black MSM couples in which at least one partner was HIV-positive and identified as a Black cisgender man. Findings showed that men varied in how involved they were in their HIV-positive partner's care and treatment, and in how they reciprocated their partner's involvement. Patterns of dyadic HIV care engagement supported a conceptual model of dyadic coordination that describes Black MSM relationships in terms of two conceptual dimensions of dyadic HIV care engagement, and guides future intervention designs with Black MSM couples.

  5. Participant Nonnaiveté and the reproducibility of cognitive psychology.

    Science.gov (United States)

    Zwaan, Rolf A; Pecher, Diane; Paolacci, Gabriele; Bouwmeester, Samantha; Verkoeijen, Peter; Dijkstra, Katinka; Zeelenberg, René

    2017-07-25

    Many argue that there is a reproducibility crisis in psychology. We investigated nine well-known effects from the cognitive psychology literature-three each from the domains of perception/action, memory, and language, respectively-and found that they are highly reproducible. Not only can they be reproduced in online environments, but they also can be reproduced with nonnaïve participants with no reduction of effect size. Apparently, some cognitive tasks are so constraining that they encapsulate behavior from external influences, such as testing situation and prior recent experience with the experiment to yield highly robust effects.

  6. Layout for Assessing Dynamic Posture: Development, Validation, and Reproducibility.

    Science.gov (United States)

    Noll, Matias; Candotti, Cláudia Tarragô; da Rosa, Bruna Nichele; Sedrez, Juliana Adami; Vieira, Adriane; Loss, Jefferson Fagundes

    2016-01-01

    To determine the psychometric properties of the layout for assessing dynamic posture (LADy). The study was divided into 2 phases: (1) development of the instrument and (2) determination of validity and reproducibility. The LADy was designed to evaluate the position adopted in 9 dynamic postures. The results confirmed the validity and reproducibility of the instrument. From a total of 51 criteria assessing 9 postures, 1 was rejected. The reproducibility for each of the criteria was classified as moderate to excellent. The LADy constitutes a valid and reproducible instrument for the evaluation of dynamic postures in children 11 to 17 years old. It is low cost and applicable in the school environment.

  7. Qualitative risk assessment in a data-scarce environment: a model to assess the impact of control measures on spread of African Swine Fever.

    Science.gov (United States)

    Wieland, Barbara; Dhollander, Sofie; Salman, Mo; Koenen, Frank

    2011-04-01

    In the absence of data, qualitative risk assessment frameworks have proved useful to assess risks associated with animal health diseases. As part of a scientific opinion for the European Commission (EC) on African Swine Fever (ASF), a working group of the European Food Safety Authority (EFSA) assessed the risk of ASF remaining endemic in Trans Caucasus Countries (TCC) and the Russian Federation (RF) and the risk of ASF becoming endemic in the EU if disease were introduced. The aim was to develop a tool to evaluate how current control or preventive measures mitigate the risk of spread and giving decision makers the means to review how strengthening of surveillance and control measures would mitigate the risk of disease spread. Based on a generic model outlining disease introduction, spread and endemicity in a region, the impact of risk mitigation measures on spread of disease was assessed for specific risk questions. The resulting hierarchical models consisted of key steps containing several sub-steps. For each step of the risk pathways risk estimates were determined by the expert group based on existing data or through expert opinion elicitation. Risk estimates were combined using two different combination matrices, one to combine estimates of independent steps and one to combine conditional probabilities. The qualitative risk assessment indicated a moderate risk that ASF will remain endemic in current affected areas in the TCC and RF and a high risk of spread to currently unaffected areas. If introduced into the EU, ASF is likely to be controlled effectively in the production sector with high or limited biosecurity. In the free range production sector, however, there is a moderate risk of ASF becoming endemic due to wild boar contact, non-compliance with animal movement bans, and difficult access to all individual pigs upon implementation of control measures. This study demonstrated the advantages of a systematic framework to assist an expert panel to carry out a

  8. Qualitative study of the behavior of minor species during a stratospheric warming with a 3-D model

    Science.gov (United States)

    Ramaroson, R.; Pirre, M.; Cariolle, D.

    1994-01-01

    It is well-known that the behavior of the ozone layer depends upon the coupling between several processes in the atmosphere. Natural or anthropogenic pollutants emitted from the surface or injected directly at high altitude may affect this layer. Assessment studies for long-term changes of the ozone layer are conducted with the aid of various two-dimensional models. These models describe the long-term and seasonal evolution of minor constituents and take into account the interaction between all processes. However, many limitations affect the self-consistency of these models e.g., the circulation in these models is only meridional and vertical and is not able to represent all types of motion in the atmosphere. During a perturbed winter in the north polar regions, the vortex is displaced from the pole to lower latitude so that wind may be reversed at a given location. Perturbed air masses are transported outside the darkened regions and may mix with local air masses. Three-dimensional models are the only tools which can describe correctly these sporadic phenomena.

  9. Estimation of the Influence of Thin Air Layers on Structures by the Use of Qualitative One-Dimensional Models

    Science.gov (United States)

    Chimeno Manguan, M.; Roibas Millan, E.; Simon Hidalgo, F.

    2014-06-01

    Air layers are regions of air between structural elements than can be found in numerous spacecraft structures. The space between folded solar panels and between antennas and a satellite's body are cases of air layers. For some cases, depending on the flexibility of the contiguous structures, the contribution of air layers can modify noticeably the dynamic response of a spacecraft structure. The analysis of these problems in detailed numerical models as Finite and Boundary Element models are characterised by a very small element size because of the requirements imposed by the thickness of the air layers and the fluid-structure interface. Then, a preliminary assessment of the influence of the air layer allows optimizing the development work flow of these elements. This work presents a methodology to preliminarily assess the influence of air layers in the structural response. The methodology is based on the definition of simplified one-dimensional models for the structure and the air gaps. The study of these simple models can be a useful tool to determine the degree of influence of the air layers in the system. Along with the introduction of the methodology a study on several of the model parameters as the number of degrees of freedom for the air layer or the structure is presented. The performance of the methodology is illustrated with results for several cases including actual spacecraft structures.

  10. Qualitative analysis in reliability and safety studies

    International Nuclear Information System (INIS)

    Worrell, R.B.; Burdick, G.R.

    1976-01-01

    The qualitative evaluation of system logic models is described as it pertains to assessing the reliability and safety characteristics of nuclear systems. Qualitative analysis of system logic models, i.e., models couched in an event (Boolean) algebra, is defined, and the advantages inherent in qualitative analysis are explained. Certain qualitative procedures that were developed as a part of fault-tree analysis are presented for illustration. Five fault-tree analysis computer-programs that contain a qualitative procedure for determining minimal cut sets are surveyed. For each program the minimal cut-set algorithm and limitations on its use are described. The recently developed common-cause analysis for studying the effect of common-causes of failure on system behavior is explained. This qualitative procedure does not require altering the fault tree, but does use minimal cut sets from the fault tree as part of its input. The method is applied using two different computer programs. 25 refs

  11. A qualitative explanation of tunneling characteristics of high-Tc junctions in terms of the McMillan proximity model

    International Nuclear Information System (INIS)

    Di Chiara, A.; Peluso, G.; Fontana, F.; Tafuri, F.

    1991-01-01

    The influence of proximity effects on the transport properties of high-T c superconductors is considered. On the basis of the experimental results on tunneling spectroscopy reported in the current literature, the authors discuss some of the main features of dI/dV vs. V characteristics. More particularly, attention is focused on the depression of gap structure, the presence of conductance peaks due to the counterelectrode gap, and 'zero-bias anomalies.' A possible explanation of those features in terms of the McMillan proximity model is given along with some examples of applications of the model to experimental data

  12. Prediction of lung tumour position based on spirometry and on abdominal displacement: Accuracy and reproducibility

    International Nuclear Information System (INIS)

    Hoisak, Jeremy D.P.; Sixel, Katharina E.; Tirona, Romeo; Cheung, Patrick C.F.; Pignol, Jean-Philippe

    2006-01-01

    Background and purpose: A simulation investigating the accuracy and reproducibility of a tumour motion prediction model over clinical time frames is presented. The model is formed from surrogate and tumour motion measurements, and used to predict the future position of the tumour from surrogate measurements alone. Patients and methods: Data were acquired from five non-small cell lung cancer patients, on 3 days. Measurements of respiratory volume by spirometry and abdominal displacement by a real-time position tracking system were acquired simultaneously with X-ray fluoroscopy measurements of superior-inferior tumour displacement. A model of tumour motion was established and used to predict future tumour position, based on surrogate input data. The calculated position was compared against true tumour motion as seen on fluoroscopy. Three different imaging strategies, pre-treatment, pre-fraction and intrafractional imaging, were employed in establishing the fitting parameters of the prediction model. The impact of each imaging strategy upon accuracy and reproducibility was quantified. Results: When establishing the predictive model using pre-treatment imaging, four of five patients exhibited poor interfractional reproducibility for either surrogate in subsequent sessions. Simulating the formulation of the predictive model prior to each fraction resulted in improved interfractional reproducibility. The accuracy of the prediction model was only improved in one of five patients when intrafractional imaging was used. Conclusions: Employing a prediction model established from measurements acquired at planning resulted in localization errors. Pre-fractional imaging improved the accuracy and reproducibility of the prediction model. Intrafractional imaging was of less value, suggesting that the accuracy limit of a surrogate-based prediction model is reached with once-daily imaging

  13. Stereographic measurement of orbital volume, a digital reproducible evaluation method.

    Science.gov (United States)

    Mottini, Matthias; Wolf, Christian A; Seyed Jafari, S Morteza; Katsoulis, Konstantinos; Schaller, Benoît

    2017-10-01

    Up to date, no standardised reproducible orbital volume measurement method is available. Therefore, this study aimed to investigate the accuracy of a new measurement method, which delineates the boundaries of orbital cavity three-dimensionally (3D). In order to calculate the orbital volume from axial CT slice images of the patients, using our first described measurement method, the segmentation of the orbital cavity and the bony skull was performed using Amira 3D Analysis Software. The files were then imported into the Blender program. The stereographic skull model was aligned based on the Frankfurt horizontal plane and superposed according to defined anatomical reference points. The anterior sectional plane ran through the most posterior section of the lacrimal fossa and the farthest dorsal point of the anterior latero-orbital margin, which is positioned perpendicular to the Frankfurt horizontal plane. The volume of each orbital cavity was then determined automatically by the Blender program. The 10 consecutive subjects (5 female, 5 male) with mean age of 50.3±21.3 years were considered for analysis in the current study. The first investigator reported a mean orbital volume of 20.24±1.01 cm3 in the first and 20.25±1.03 cm3 in the second evaluation. Furthermore, the intraclass correlation coefficient (ICC) showed an excellent intrarater agreement (ICC=0.997). Additionally, the second investigator detected a mean orbital volume of 20.20±1.08 cm3 in his assessment, in which an excellent inter-rater agreement was found in ICC (ICC=0.994). This method provides a standardised and reproducible 3D approach to the measurement of the orbital volume. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  14. The Impact of Three-Dimensional Computational Modeling on Student Understanding of Astronomy Concepts: A Qualitative Analysis. Research Report

    Science.gov (United States)

    Hansen, John; Barnett, Michael; MaKinster, James; Keating, Thomas

    2004-01-01

    In this study, we explore an alternate mode for teaching and learning the dynamic, three-dimensional (3D) relationships that are central to understanding astronomical concepts. To this end, we implemented an innovative undergraduate course in which we used inexpensive computer modeling tools. As the second of a two-paper series, this report…

  15. Re-Imagining Initial Multiracial Teacher Education (IMTE) Model through the ODL Philosophy: A Critical Qualitative Meta-Synthesis Study

    Science.gov (United States)

    Nyoni, J.

    2012-01-01

    This article reports on a critical meta-analysis of empirical studies done by human sciences researchers on the initial multicultural teacher education (IMTE) models in multicultural post-colonial transitional societies with reference to sub-Saharan African states in general and South Africa in particular. Using a critical post-positivist…

  16. Digital Video as a Personalized Learning Assignment: A Qualitative Study of Student Authored Video Using the ICSDR Model

    Science.gov (United States)

    Campbell, Laurie O.; Cox, Thomas D.

    2018-01-01

    Students within this study followed the ICSDR (Identify, Conceptualize/Connect, Storyboard, Develop, Review/Reflect/Revise) development model to create digital video, as a personalized and active learning assignment. The participants, graduate students in education, indicated that following the ICSDR framework for student-authored video guided…

  17. Qualitative understanding of the sign of t' asymmetry in the extended t-J Model and relevance for pairing properties

    Science.gov (United States)

    Martins, George; Xavier, Jose; Arrachea, Liliana; Dagotto, Elbio

    2002-03-01

    Numerical calculations illustrate the effect of the sign of the next nearest-neighbor hopping term t' on the 2-hole properties of the t-t'-J model. Working mainly on 2-leg ladders, in the -1.0 0. This interference is destructive for t'<0.

  18. Organ-on-a-Chip Technology for Reproducing Multiorgan Physiology.

    Science.gov (United States)

    Lee, Seung Hwan; Sung, Jong Hwan

    2018-01-01

    In the drug development process, the accurate prediction of drug efficacy and toxicity is important in order to reduce the cost, labor, and effort involved. For this purpose, conventional 2D cell culture models are used in the early phase of drug development. However, the differences between the in vitro and the in vivo systems have caused the failure of drugs in the later phase of the drug-development process. Therefore, there is a need for a novel in vitro model system that can provide accurate information for evaluating the drug efficacy and toxicity through a closer recapitulation of the in vivo system. Recently, the idea of using microtechnology for mimicking the microscale tissue environment has become widespread, leading to the development of "organ-on-a-chip." Furthermore, the system is further developed for realizing a multiorgan model for mimicking interactions between multiple organs. These advancements are still ongoing and are aimed at ultimately developing "body-on-a-chip" or "human-on-a-chip" devices for predicting the response of the whole body. This review summarizes recently developed organ-on-a-chip technologies, and their applications for reproducing multiorgan functions. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. What is eHealth (6)? Development of a Conceptual Model for eHealth: Qualitative Study with Key Informants.

    Science.gov (United States)

    Shaw, Tim; McGregor, Deborah; Brunner, Melissa; Keep, Melanie; Janssen, Anna; Barnet, Stewart

    2017-10-24

    Despite rapid growth in eHealth research, there remains a lack of consistency in defining and using terms related to eHealth. More widely cited definitions provide broad understanding of eHealth but lack sufficient conceptual clarity to operationalize eHealth and enable its implementation in health care practice, research, education, and policy. Definitions that are more detailed are often context or discipline specific, limiting ease of translation of these definitions across the breadth of eHealth perspectives and situations. A conceptual model of eHealth that adequately captures its complexity and potential overlaps is required. This model must also be sufficiently detailed to enable eHealth operationalization and hypothesis testing. This study aimed to develop a conceptual practice-based model of eHealth to support health professionals in applying eHealth to their particular professional or discipline contexts. We conducted semistructured interviews with key informants (N=25) from organizations involved in health care delivery, research, education, practice, governance, and policy to explore their perspectives on and experiences with eHealth. We used purposeful sampling for maximum diversity. Interviews were coded and thematically analyzed for emergent domains. Thematic analyses revealed 3 prominent but overlapping domains of eHealth: (1) health in our hands (using eHealth technologies to monitor, track, and inform health), (2) interacting for health (using digital technologies to enable health communication among practitioners and between health professionals and clients or patients), and (3) data enabling health (collecting, managing, and using health data). These domains formed a model of eHealth that addresses the need for clear definitions and a taxonomy of eHealth while acknowledging the fluidity of this area and the strengths of initiatives that span multiple eHealth domains. This model extends current understanding of eHealth by providing clearly

  20. Repeatability and reproducibility of Population Viability Analysis (PVA and the implications for threatened species management

    Directory of Open Access Journals (Sweden)

    Clare Morrison

    2016-08-01

    Full Text Available Conservation triage focuses on prioritizing species, populations or habitats based on urgency, biodiversity benefits, recovery potential as well as cost. Population Viability Analysis (PVA is frequently used in population focused conservation prioritizations. The critical nature of many of these management decisions requires that PVA models are repeatable and reproducible to reliably rank species and/or populations quantitatively. This paper assessed the repeatability and reproducibility of a subset of previously published PVA models. We attempted to rerun baseline models from 90 publicly available PVA studies published between 2000-2012 using the two most common PVA modelling software programs, VORTEX and RAMAS-GIS. Forty percent (n = 36 failed, 50% (45 were both repeatable and reproducible, and 10% (9 had missing baseline models. Repeatability was not linked to taxa, IUCN category, PVA program version used, year published or the quality of publication outlet, suggesting that the problem is systemic within the discipline. Complete and systematic presentation of PVA parameters and results are needed to ensure that the scientific input into conservation planning is both robust and reliable, thereby increasing the chances of making decisions that are both beneficial and defensible. The implications for conservation triage may be far reaching if population viability models cannot be reproduced with confidence, thus undermining their intended value.

  1. Evaluation of how a curriculum change in nurse education was managed through the application of a business change management model: A qualitative case study.

    Science.gov (United States)

    Chowthi-Williams, Annette; Curzio, Joan; Lerman, Stephen

    2016-01-01

    Curriculum changes are a regular feature of nurse education, yet little is known about how such changes are managed. Research in this arena is yet to emerge. Evaluation of how a curriculum change in nurse education was managed through the application of a business change management model. A qualitative case study: the single case was the new curriculum, the Primary Care Pathway. One executive, three senior managers, two academics and nineteen students participated in this study in one faculty of health and social care in a higher education institution. The findings suggest that leadership was pivotal to the inception of the programme and guiding teams managed the change and did not take on a leadership role. The vision for the change and efforts to communicate it did not reach the frontline. Whilst empowerment was high amongst stakeholders and students, academics felt dis-empowered. Short-term wins were not significant in keeping up the momentum of change. The credibility of the change was under challenge and the concept of the new programme was not yet embedded in academia. Differences between the strategic and operational part of the organisation surfaced with many challenges occurring at the implementation stage. The business change model used was valuable, but was found to not be applicable during curriculum changes in nurse education. A new change model emerged, and a tool was developed alongside to aid future curriculum changes. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Keeping up with Sustainability : A Qualitative Study of Business Models and Sustainable Product Design in Design companies

    OpenAIRE

    Björnström, Marina; Grahn, Stina

    2017-01-01

    There is an increasing awareness of the impact of sustainability in the world, and to encourage organizations to engage in sustainable behavior across their processes and consider the whole product lifecycle, The European Commission (European Commission, 2017) has created an action plan for this. There are many ways for companies to engage in sustainability, whether it is through the business model where they can add demands on, for example the suppliers, or if it is through choosing a materi...

  3. A model of self-directed learning in internal medicine residency: a qualitative study using grounded theory.

    Science.gov (United States)

    Sawatsky, Adam P; Ratelle, John T; Bonnes, Sara L; Egginton, Jason S; Beckman, Thomas J

    2017-02-02

    Existing theories of self-directed learning (SDL) have emphasized the importance of process, personal, and contextual factors. Previous medical education research has largely focused on the process of SDL. We explored the experience with and perception of SDL among internal medicine residents to gain understanding of the personal and contextual factors of SDL in graduate medical education. Using a constructivist grounded theory approach, we conducted 7 focus group interviews with 46 internal medicine residents at an academic medical center. We processed the data by using open coding and writing analytic memos. Team members organized open codes to create axial codes, which were applied to all transcripts. Guided by a previous model of SDL, we developed a theoretical model that was revised through constant comparison with new data as they were collected, and we refined the theory until it had adequate explanatory power and was appropriately grounded in the experiences of residents. We developed a theoretical model of SDL to explain the process, personal, and contextual factors affecting SDL during residency training. The process of SDL began with a trigger that uncovered a knowledge gap. Residents progressed to formulating learning objectives, using resources, applying knowledge, and evaluating learning. Personal factors included motivations, individual characteristics, and the change in approach to SDL over time. Contextual factors included the need for external guidance, the influence of residency program structure and culture, and the presence of contextual barriers. We developed a theoretical model of SDL in medical education that can be used to promote and assess resident SDL through understanding the process, person, and context of SDL.

  4. Homotopy deform method for reproducing kernel space for ...

    Indian Academy of Sciences (India)

    In this paper, the combination of homotopy deform method (HDM) and simplified reproducing kernel method (SRKM) is introduced for solving the boundary value problems (BVPs) of nonlinear differential equations. The solution methodology is based on Adomian decomposition and reproducing kernel method (RKM).

  5. Genotypic variability enhances the reproducibility of an ecological study.

    Science.gov (United States)

    Milcu, Alexandru; Puga-Freitas, Ruben; Ellison, Aaron M; Blouin, Manuel; Scheu, Stefan; Freschet, Grégoire T; Rose, Laura; Barot, Sebastien; Cesarz, Simone; Eisenhauer, Nico; Girin, Thomas; Assandri, Davide; Bonkowski, Michael; Buchmann, Nina; Butenschoen, Olaf; Devidal, Sebastien; Gleixner, Gerd; Gessler, Arthur; Gigon, Agnès; Greiner, Anna; Grignani, Carlo; Hansart, Amandine; Kayler, Zachary; Lange, Markus; Lata, Jean-Christophe; Le Galliard, Jean-François; Lukac, Martin; Mannerheim, Neringa; Müller, Marina E H; Pando, Anne; Rotter, Paula; Scherer-Lorenzen, Michael; Seyhun, Rahme; Urban-Mead, Katherine; Weigelt, Alexandra; Zavattaro, Laura; Roy, Jacques

    2018-02-01

    Many scientific disciplines are currently experiencing a 'reproducibility crisis' because numerous scientific findings cannot be repeated consistently. A novel but controversial hypothesis postulates that stringent levels of environmental and biotic standardization in experimental studies reduce reproducibility by amplifying the impacts of laboratory-specific environmental factors not accounted for in study designs. A corollary to this hypothesis is that a deliberate introduction of controlled systematic variability (CSV) in experimental designs may lead to increased reproducibility. To test this hypothesis, we had 14 European laboratories run a simple microcosm experiment using grass (Brachypodium distachyon L.) monocultures and grass and legume (Medicago truncatula Gaertn.) mixtures. Each laboratory introduced environmental and genotypic CSV within and among replicated microcosms established in either growth chambers (with stringent control of environmental conditions) or glasshouses (with more variable environmental conditions). The introduction of genotypic CSV led to 18% lower among-laboratory variability in growth chambers, indicating increased reproducibility, but had no significant effect in glasshouses where reproducibility was generally lower. Environmental CSV had little effect on reproducibility. Although there are multiple causes for the 'reproducibility crisis', deliberately including genetic variability may be a simple solution for increasing the reproducibility of ecological studies performed under stringently controlled environmental conditions.

  6. Completely reproducible description of digital sound data with cellular automata

    International Nuclear Information System (INIS)

    Wada, Masato; Kuroiwa, Jousuke; Nara, Shigetoshi

    2002-01-01

    A novel method of compressive and completely reproducible description of digital sound data by means of rule dynamics of CA (cellular automata) is proposed. The digital data of spoken words and music recorded with the standard format of a compact disk are reproduced completely by this method with use of only two rules in a one-dimensional CA without loss of information

  7. Participant Nonnaiveté and the reproducibility of cognitive psychology

    NARCIS (Netherlands)

    R.A. Zwaan (Rolf); D. Pecher (Diane); G. Paolacci (Gabriele); S. Bouwmeester (Samantha); P.P.J.L. Verkoeijen (Peter); K. Dijkstra (Katinka); R. Zeelenberg (René)

    2017-01-01

    textabstractMany argue that there is a reproducibility crisis in psychology. We investigated nine well-known effects from the cognitive psychology literature—three each from the domains of perception/action, memory, and language, respectively—and found that they are highly reproducible. Not only can

  8. Model of Procedure Usage – Results from a Qualitative Study to Inform Design of Computer-Based Procedures

    Energy Technology Data Exchange (ETDEWEB)

    Johanna H Oxstrand; Katya L Le Blanc

    2012-07-01

    The nuclear industry is constantly trying to find ways to decrease the human error rate, especially the human errors associated with procedure use. As a step toward the goal of improving procedure use performance, researchers, together with the nuclear industry, have been looking at replacing the current paper-based procedures with computer-based procedure systems. The concept of computer-based procedures is not new by any means; however most research has focused on procedures used in the main control room. Procedures reviewed in these efforts are mainly emergency operating procedures and normal operating procedures. Based on lessons learned for these previous efforts we are now exploring a more unknown application for computer based procedures - field procedures, i.e. procedures used by nuclear equipment operators and maintenance technicians. The Idaho National Laboratory, the Institute for Energy Technology, and participants from the U.S. commercial nuclear industry are collaborating in an applied research effort with the objective of developing requirements and specifications for a computer-based procedure system to be used by field operators. The goal is to identify the types of human errors that can be mitigated by using computer-based procedures and how to best design the computer-based procedures to do this. The underlying philosophy in the research effort is “Stop – Start – Continue”, i.e. what features from the use of paper-based procedures should we not incorporate (Stop), what should we keep (Continue), and what new features or work processes should be added (Start). One step in identifying the Stop – Start – Continue was to conduct a baseline study where affordances related to the current usage of paper-based procedures were identified. The purpose of the study was to develop a model of paper based procedure use which will help to identify desirable features for computer based procedure prototypes. Affordances such as note taking, markups

  9. New models to support the professional education of health visitors: A qualitative study of the role of space and place in creating 'community of learning hubs'.

    Science.gov (United States)

    Donetto, Sara; Malone, Mary; Sayer, Lynn; Robert, Glenn

    2017-07-01

    In response to a policy-driven workforce expansion in England new models of preparing health visitors for practice have been implemented. 'Community of Learning hubs' (COLHs) are one such model, involving different possible approaches to student support in clinical practice placements (for example, 'long arm mentoring' or 'action learning set' sessions). Such models present opportunities for studying the possible effects of spatiality on the learning experiences of students and newly qualified health visitors, and on team relationships more broadly. To explore a 'community of learning hub' model in health visitor education and reflect on the role of space and place in the learning experience and professional identity development of student health visitors. Qualitative research conducted during first year of implementation. Three 'community of learning hub' projects based in two NHS community Trusts in London during the period 2013-2015. Managers and leads (n=7), practice teachers and mentors (n=6) and newly qualified and student health visitors (n=16). Semi-structured, audio-recorded interviews analysed thematically. Participants had differing views as to what constituted a 'hub' in their projects. Two themes emerged around the spaces that shape the learning experience of student and newly qualified health visitors. Firstly, a generalised need for a 'quiet place' which allows pause for reflection but also for sharing experiences and relieving common anxieties. Secondly, the role of physical arrangements in open-plan spaces to promote access to support from more experienced practitioners. Attention to spatiality can shed light on important aspects of teaching and learning practices, and on the professional identities these practices shape and support. New configurations of time and space as part of educational initiatives can surface new insights into existing practices and learning models. Copyright © 2017. Published by Elsevier Ltd.

  10. Evaluation of how a real time pre-registration health care curricula was managed through the application of a newly designed Change Management Model: A qualitative case study.

    Science.gov (United States)

    Chowthi-Williams, Annette

    2018-02-01

    Curricula change in nurse education is of international importance. The pace of such change has been continuous and has triggered criticisms of inadequate preparation of practitioners. There are no change formulae for managing curricula change and despite a raft of change methods, globally change success remains low. A lack of a unified voice, undue focus on cognition, and arguably no existing models for academia and a literature gap contribute to change challenge. A new Change Management Model designed from research with emotion as its underpinning philosophy is evaluated. Evaluation of a newly designed Change Management Model through a real time pre-registration health care curricula change. A qualitative case study was adopted. The single case study was the new pre-registration health care curricula. This study took place in a Faculty of Health and Social care in one HEI in the UK. Four senior academics and fifteen academics across professions and specialisms involved in the curricula change took part in the study. The findings suggested that leadership operated differently throughout the organisation. Distributive and collective leadership created a critical mass of people to help deliver the new curricula but academics felt excluded at the strategic level. Emotion at the strategic level inhibited innovation but boosted engagement, emotional relationships and creativity at the operational level. Face to face communication was favoured for its emotional connection. A top down approach created an emotional disconnect and impacted inclusiveness, engagement, empowerment, vision and readiness for change. Testing the new model widely not only in organisations, practice and team changes but personal change in improving health and wellbeing could be beneficial. The continuing gap in knowledge on the link between emotion and curricula change, practice and organisational change and therapeutic value of the model also warrants further research. Crown Copyright © 2017

  11. Checklist for the qualitative evaluation of clinical studies with particular focus on external validity and model validity

    Directory of Open Access Journals (Sweden)

    Vollmar Horst C

    2006-12-01

    Full Text Available Abstract Background It is often stated that external validity is not sufficiently considered in the assessment of clinical studies. Although tools for its evaluation have been established, there is a lack of awareness of their significance and application. In this article, a comprehensive checklist is presented addressing these relevant criteria. Methods The checklist was developed by listing the most commonly used assessment criteria for clinical studies. Additionally, specific lists for individual applications were included. The categories of biases of internal validity (selection, performance, attrition and detection bias correspond to structural, treatment-related and observational differences between the test and control groups. Analogously, we have extended these categories to address external validity and model validity, regarding similarity between the study population/conditions and the general population/conditions related to structure, treatment and observation. Results A checklist is presented, in which the evaluation criteria concerning external validity and model validity are systemised and transformed into a questionnaire format. Conclusion The checklist presented in this article can be applied to both planning and evaluating of clinical studies. We encourage the prospective user to modify the checklists according to the respective application and research question. The higher expenditure needed for the evaluation of clinical studies in systematic reviews is justified, particularly in the light of the influential nature of their conclusions on therapeutic decisions and the creation of clinical guidelines.

  12. Effect of skin metabolism on dermal delivery of testosterone: qualitative assessment using a new short-term skin model.

    Science.gov (United States)

    Jacques, C; Perdu, E; Jamin, E L; Cravedi, J P; Mavon, A; Duplan, H; Zalko, D

    2014-01-01

    The skin is a metabolically active organ expressing biotransformation enzymes able to metabolize both endogenous molecules and xenobiotics. We investigated the impact of metabolism on the delivery of testosterone through the skin with an ex vivo pig ear skin system as an alternative model for human skin. Penetration, absorption and metabolic capabilities were investigated up to 72 h after application of [(14)C]-testosterone doses of 50-800 nmol on either fresh or frozen skin, with the latter model being metabolically inactive. Testosterone absorption and metabolite production were monitored by radio-HPLC and gas chromatography-mass spectrometry. Testosterone absorption through frozen skin was much lower, irrespective of the dose of testosterone applied, compared to fresh skin. Using fresh skin samples, >95% of the radioactivity recovered in culture media, as well as the skin itself, corresponded to metabolites. These results were compared with the metabolic data obtained from other in vitro systems (liver and skin microsomes). The present work leads to the conclusion that most of the enzymatic activities expressed in liver fractions are also expressed in pig and human skin. The metabolic activity of the skin can modulate the biological activity of pharmaceuticals (and xenobiotics). Consequently, it can also greatly affect transdermal drug delivery.

  13. Qualitative Tourism Research

    NARCIS (Netherlands)

    Buda, Dorina; Martini, Annaclaudia; Garcia, Luis-Manuel; Lowry, Linda

    Conducting qualitative research in tourism studies entails engaging with an entire approach, a set of methods that shape project design, conceptual frameworks, data analysis, and anticipated outcomes. Standard qualitative methods are individual interviews, focus groups and ethnography. Solicited

  14. HCG blood test - qualitative

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/003509.htm HCG blood test - qualitative To use the sharing features on this page, please enable JavaScript. A qualitative HCG blood test checks if there is a hormone called human ...

  15. The origins of the spanish railroad accounting model: a qualitative study of the MZA'S operating account (1856-1874

    Directory of Open Access Journals (Sweden)

    Beatriz Santos

    2014-12-01

    Full Text Available The lack of external regulation about the form and substance of the financial statements that railroad companies had to report during the implementation phase of the Spanish railway, meant that each company developed its own accounting model. In this study we have described, analysed and interpreted the more relevant changes in the accounting information in relation to the business result. Using the analysis of an historical case, we developed an ad-hoc research tool, for recording all the changes of the operating account. The results of the study prove that MZA’s operating account reflected the particularities of the railway business although subject to limitations, and the reported information improved during the study period in terms of relevance and reliability

  16. Adolescents’ associations between travel behaviour and environmental impact: A qualitative study based on the Norm-Activation Model

    DEFF Research Database (Denmark)

    Møller, Mette; Haustein, Sonja; Bohlbro, Marie S.

    2018-01-01

    The negative environmental impact of car-dependent daily transport is well known. Young people of today are the potential drivers of the future and their mode choice will influence the environment for many years. This study explores the associations drawn between daily transport and environmental...... impact among 15-year-old Danish adolescents. We conducted 50 in-depth interviews and analysed them using a data-driven inductive thematic approach. We interpret differences in pro-environmental awareness and engagement on the background of the Norm-Activation Model (Schwartz, 1977). Based...... transport as a relevant issue in relation to sustainability. Such measures should include tangible feedback in a daily context while taking different coping strategies with regard to climate change into account....

  17. THE DURATION AND PHASES OF QUALITATIVE RESEARCH

    OpenAIRE

    Natasha ANGELOSKA-GALEVSKA

    1998-01-01

    Text points to the main characteristics of the research process when we use qualitative approach. Qualitative research design differs from the conventional linear model, which is typical for quantitative research. Qualitative research begins with selection of a research problem and then follows a cyclical pattern in which changes can be made in any phase of the research. New questions, tasks and hypotheses generate during the research and collection and analysis of data can be done in success...

  18. The qualitative research proposal

    OpenAIRE

    Klopper, Hester

    2008-01-01

    Qualitative research in the health sciences has had to overcome many prejudices and a number of misunderstandings, but today qualitative research is as acceptable as quantitative research designs and is widely funded and published. Writing the proposal of a qualitative study, however, can be a challenging feat, due to the emergent nature of the qualitative research design and the description of the methodology as a process. Even today, many sub-standard proposals at post-graduate evaluation c...

  19. Development of an explanatory model of sexual intimacy following treatment for localised prostate cancer: A systematic review and meta-synthesis of qualitative evidence.

    Science.gov (United States)

    Tucker, Samantha R; Speer, Susan A; Peters, Sarah

    2016-08-01

    Prostate cancer is a leading cause of cancer in men, affecting one in eight. An ageing population coupled with increased testing indicates that the incidence of early-stage prostate cancer is rising rapidly. Treatments are effective, but all can result in chronic sexual side effects and impact on the psychological, emotional and relational components of sexual functioning. Whilst the physical consequences of treatment are well documented, we lack a comprehensive picture of the effects of localised prostate cancer treatment on men's experience of sexual intimacy and how this may affect survivorship and recovery. This study synthesises the qualitative literature related to men's experience of sexual intimacy in the context of localised prostate cancer. A systematic search strategy identified 12 studies, which were assessed using a modified version of the Critical Appraisal Skills Programme. Using Noblit and Hare's (1988) approach, a meta-synthesis was conducted. Findings are organised within four inter-related themes that form the basis of a new conceptual explanatory model: (i) Loss and grief: Destroyed intimacy; (ii) Going through the motions: Artificial intimacy; (iii) Fear of failure: Avoiding intimacy and (iv) Breaking barriers: Constructing an alternative intimacy. The LMAC (Loss, Motions, Avoidance and Construction) model provides a new way of conceptualising sexual recovery following prostate cancer treatment and opportunities for health care professionals to support men and their partners. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. How market-oriented education policies might influence young people's health: development of a logic model from qualitative case studies in English secondary schools.

    Science.gov (United States)

    Bonell, Chris; Fletcher, Adam; Sorhaindo, Annik; Wells, Helene; McKee, Martin

    2012-07-01

    School systems are increasingly typified by diversity of provision, parental choice and publication of performance data. Schools shape their students' lifestyles and health, but the effects of 'marketisation' are under-researched. The authors use qualitative data to develop a logic model regarding such effects. Case studies in seven English secondary schools, interviews with 103 students and 39 staff. 'Parental choice' was associated with dispersal of students' friendship groups on transition to secondary school, reduced social support and emotional harms. 'Choice' meant some schools were regarded as 'dumping grounds' for socially disadvantaged students, creating potentially violent environments where students engaged in risk behaviours such as substance use to facilitate protective bonds with peers. Schools focused strongly on academic attainment, reflecting external pressures from the school inspectorate and performance league tables. Some schools sought to improve their league table position by targeting resources on 'key marginal' students on the threshold of passing five exams, the key metric. Less-academic students commonly became disengaged, engaging in various health risk behaviours as alternative status markers. The exam-focused environment aroused anxiety among high and low attainers, some using substances as self-medication. Schools also de-prioritised health education and sport in this performance-driven context. Our logic model aims to guide further research on how marketisation might affect young people health behaviours.

  1. The Health Belief Model: A Qualitative Study to Understand High-risk Sexual Behavior in Chinese Men Who Have Sex With Men.

    Science.gov (United States)

    Li, Xianhong; Lei, Yunxiao; Wang, Honghong; He, Guoping; Williams, Ann Bartley

    2016-01-01

    The Health Belief Model (HBM) has been widely used to explain rationales for health risk-taking behaviors. Our qualitative study explored the applicability of the HBM to understand high-risk sexual behavior in Chinese men who have sex with men (MSM) and to elaborate each component of the model. HIV knowledge and perception of HIV prevalence contributed to perceived susceptibility. An attitude of treatment optimism versus hard life in reality affected perceived severity. Perceived barriers included discomfort using condoms and condom availability. Perceived benefits included prevention of HIV and other sexually transmitted illnesses. Sociocultural cues for Chinese MSM were elaborated according to each component. The results demonstrated that the HBM could be applied to Chinese MSM. When used with this group, it provided information to help develop a population- and disease-specific HBM scale. Results of our study also suggested behavioral interventions that could be used with Chinese MSM to increase condom use. Copyright © 2016 Association of Nurses in AIDS Care. All rights reserved.

  2. Highly reproducible and sensitive silver nanorod array for the rapid detection of Allura Red in candy

    Science.gov (United States)

    Yao, Yue; Wang, Wen; Tian, Kangzhen; Ingram, Whitney Marvella; Cheng, Jie; Qu, Lulu; Li, Haitao; Han, Caiqin

    2018-04-01

    Allura Red (AR) is a highly stable synthetic red azo dye, which is widely used in the food industry to dye food and increase its attraction to consumers. However, the excessive consumption of AR can result in adverse health effects to humans. Therefore, a highly reproducible silver nanorod (AgNR) array was developed for surface enhanced Raman scattering (SERS) detection of AR in candy. The relative standard deviation (RSD) of AgNR substrate obtained from the same batch and different batches were 5.7% and 11.0%, respectively, demonstrating the high reproducibility. Using these highly reproducible AgNR arrays as the SERS substrates, AR was detected successfully, and its characteristic peaks were assigned by the density function theory (DFT) calculation. The limit of detection (LOD) of AR was determined to be 0.05 mg/L with a wide linear range of 0.8-100 mg/L. Furthermore, the AgNR SERS arrays can detect AR directly in different candy samples within 3 min without any complicated pretreatment. These results suggest the AgNR array can be used for rapid and qualitative SERS detection of AR, holding a great promise for expanding SERS application in food safety control field.

  3. Assessing community perspectives of the community based education and service model at Makerere University, Uganda: a qualitative evaluation.

    Science.gov (United States)

    Mbalinda, Scovia N; Plover, Colin M; Burnham, Gilbert; Kaye, Dan; Mwanika, Andrew; Oria, Hussein; Okullo, Isaac; Muhwezi, Wilson; Groves, Sara

    2011-03-09

    Community partnerships are defined as groups working together with shared goals, responsibilities, and power to improve the community. There is growing evidence that these partnerships contribute to the success and sustainability of community-based education and service programs (COBES), facilitating change in community actions and attitudes. Makerere University College of Health Sciences (MakCHS) is forging itself as a transformational institution in Uganda and the region. The College is motivated to improve the health of Ugandans through innovative responsive teaching, provision of service, and community partnerships. Evaluating the COBES program from the community perspective can assist the College in refining an innovative and useful model that has potential to improve the health of Ugandans. A stratified random sample of 11 COBES sites was selected to examine the community's perception of the program. Key Informant Interviews of 11 site tutors and 33 community members were completed. The data was manually analyzed and themes developed. Communities stated the students consistently engaged with them with culturally appropriate behaviour. They rated the student's communication as very good even though translators were frequently needed. Half the community stated they received some feedback from the students, but some communities interpreted any contact after the initial visit as feedback. Communities confirmed and appreciated that the students provided a number of interventions and saw positive changes in health and health seeking behaviours. The community reflected that some programs were more sustainable than others; the projects that needed money to implement were least sustainable. The major challenges from the community included community fatigue, and poor motivation of community leaders to continue to take students without compensation. Communities hosting Makerere students valued the students' interventions and the COBES model. They reported witnessing

  4. Assessing community perspectives of the community based education and service model at Makerere University, Uganda: a qualitative evaluation

    Directory of Open Access Journals (Sweden)

    Okullo Isaac

    2011-03-01

    Full Text Available Abstract Background Community partnerships are defined as groups working together with shared goals, responsibilities, and power to improve the community. There is growing evidence that these partnerships contribute to the success and sustainability of community-based education and service programs (COBES, facilitating change in community actions and attitudes. Makerere University College of Health Sciences (MakCHS is forging itself as a transformational institution in Uganda and the region. The College is motivated to improve the health of Ugandans through innovative responsive teaching, provision of service, and community partnerships. Evaluating the COBES program from the community perspective can assist the College in refining an innovative and useful model that has potential to improve the health of Ugandans. Methods A stratified random sample of 11 COBES sites was selected to examine the community’s perception of the program. Key Informant Interviews of 11 site tutors and 33 community members were completed. The data was manually analyzed and themes developed. Results Communities stated the students consistently engaged with them with culturally appropriate behaviour. They rated the student’s communication as very good even though translators were frequently needed. Half the community stated they received some feedback from the students, but some communities interpreted any contact after the initial visit as feedback. Communities confirmed and appreciated that the students provided a number of interventions and saw positive changes in health and health seeking behaviours. The community reflected that some programs were more sustainable than others; the projects that needed money to implement were least sustainable. The major challenges from the community included community fatigue, and poor motivation of community leaders to continue to take students without compensation. Conclusions Communities hosting Makerere students valued the

  5. Qualitative Content Analysis

    OpenAIRE

    Satu Elo; Maria Kääriäinen; Outi Kanste; Tarja Pölkki; Kati Utriainen; Helvi Kyngäs

    2014-01-01

    Qualitative content analysis is commonly used for analyzing qualitative data. However, few articles have examined the trustworthiness of its use in nursing science studies. The trustworthiness of qualitative content analysis is often presented by using terms such as credibility, dependability, conformability, transferability, and authenticity. This article focuses on trustworthiness based on a review of previous studie...

  6. Quantitative and qualitative variation of fat in model vanilla custard desserts: effects on sensory properties and consumer acceptance.

    Science.gov (United States)

    Tomaschunas, Maja; Köhn, Ehrhard; Bennwitz, Petra; Hinrichs, Jörg; Busch-Stockfisch, Mechthild

    2013-06-01

    The effects of variation in fat content (0.1% to 15.8%) and type of fat, using different types of milk, dairy cream, or vegetable fat cream, on sensory characteristics and consumer acceptance of starch-based vanilla model custards were studied. Descriptive analysis with trained panelists and consumer testing with untrained assessors were applied. Descriptive data were related to hedonic data using principal component analysis to determine drivers of liking and disliking. Results demonstrated an increasing effect of fat concerning visual and oral thickness, creamy flavor, and fat-related texture properties, as well as a decreasing effect concerning yellow color and surface shine. A lack of fat caused moderate intensities in pudding-like flavor attributes and an intensive jelly texture. Adding a vegetable fat cream led to lower intensities in attributes yellow color, cooked flavor, thick, and jelly texture, whereas intensities in vegetable fat flavor and fat-related texture properties increased. All consumers favored custards with medium fat contents, being high in pudding-like and vegetable fat flavor as well as in fat-related texture attributes. Nonfat custards were rejected due to jelly texture and moderate intensities in pudding-flavor attributes. High-fat samples were liked by some consumers, but their high intensities in thickness, white color, and creamy flavor also drove disliking for others. © 2013 Institute of Food Technologists®

  7. In-vitro accuracy and reproducibility evaluation of probing depth measurements of selected periodontal probes

    Directory of Open Access Journals (Sweden)

    K.N. Al Shayeb

    2014-01-01

    Conclusion: Depth measurements with the Chapple UB-CF-15 probe were more accurate and reproducible compared to measurements with the Vivacare TPS and Williams 14 W probes. This in vitro model may be useful for intra-examiner calibration or clinician training prior to the clinical evaluation of patients or in longitudinal studies involving periodontal evaluation.

  8. Parental decision-making on utilisation of out-of-home respite in children's palliative care: findings of qualitative case study research - a proposed new model.

    Science.gov (United States)

    Ling, J; Payne, S; Connaire, K; McCarron, M

    2016-01-01

    Respite in children's palliative care aims to provide a break for family's from the routine of caring. Parental decision-making regarding the utilisation of out-of-home respite is dependent on many interlinking factors including the child's age, diagnosis, geographical location and the family's capacity to meet their child's care needs. A proposed model for out-of-home respite has been developed based on the findings of qualitative case study research. Utilising multiple, longitudinal, qualitative case study design, the respite needs and experiences of parents caring for a child with a life-limiting condition were explored. Multiple, in-depth interviews were undertaken with the parents identified by a hospital-based children's palliative care team. Data were analysed using thematic analysis. Each individual case consists of a whole study. Cross-case comparison was also conducted. Nine families were recruited and followed for two years. A total of 19 in-depth interviews were conducted with mothers and fathers (one or both) caring for a child with a life-limiting condition in Ireland. Each family reported vastly different needs and experiences of respite from their own unique perspective. Cross-case comparison showed that for all parents utilising respite care, regardless of their child's age and condition, home was the location of choice. Many interlinking factors influencing these decisions included: past experience of in-patient care, and trust and confidence in care providers. Issues were raised regarding the impact of care provision in the home on family life, siblings and the concept of home. Respite is an essential element of children's palliative care. Utilisation of out-of-home respite is heavily dependent on a number of interlinked and intertwined factors. The proposed model of care offers an opportunity to identify how these decisions are made and may ultimately assist in identifying the elements of responsive and family-focused respite that are important

  9. A Low-Cost Anthropometric Walking Robot for Reproducing Gait Lab Data

    Directory of Open Access Journals (Sweden)

    Rogério Eduardo da Silva Santana

    2008-01-01

    Full Text Available Human gait analysis is one of the resources that may be used in the study and treatment of pathologies of the locomotive system. This paper deals with the modelling and control aspects of the design, construction and testing of a biped walking robot conceived to, in limited extents, reproduce the human gait. Robot dimensions have been chosen in order to guarantee anthropomorphic proportions and then to help health professionals in gait studies. The robot has been assembled with low-cost components and can reproduce, in an assisted way, real-gait patterns generated from data previously acquired in gait laboratories. Part of the simulated and experimental results are addressed to demonstrate the ability of the biped robot in reproducing normal and pathological human gait.

  10. Successful self-directed lifelong learning in medicine: a conceptual model derived from qualitative analysis of a national survey of pediatric residents.

    Science.gov (United States)

    Li, Su-Ting T; Paterniti, Debora A; Co, John Patrick T; West, Daniel C

    2010-07-01

    Self-directed lifelong learning is integral to medical professionalism, yet how best to encourage its development during clinically intensive training is unknown. The authors develop a model for successful self-directed learning by analyzing qualitative data from a national survey of residents. Pediatric and medicine/pediatric residents at 46 training programs completed a Web-based survey in 2008-2009. Self-reported barriers to and strategies for achieving self-directed learning goals were systematically analyzed through inductive iterative review. A total of 992 out of 1,739 (57%) residents responded. Barriers to achieving self-directed learning goals were categorized into difficulty with personal reflection, environmental strain, competing demands, difficulty with goal generation, and problems with plan development and implementation. Strategies for achieving learning goals included creating goals that were important (relevant to the learner and prioritized by the learner as important to achieve), specific (with broad goals broken down into incremental steps and a specific plan for each step), measurable, accountable (with reminder and tracking systems and building in internal and external accountability), realistic (achievable goals which utilize existing opportunities and constant self-adjustment), and included a timeline for completing the goal (and incorporating the goal into their daily routine). On the basis of the data, the authors propose a conceptual model for self-directed lifelong learning involving creation of learning goals and plan development based on individual reflection and self-assessment, and continual revision of goals and/or plans based on degree of goal attainment. This model could be broadly applicable throughout medical education.

  11. REPRODUCIBLE DRUG REPURPOSING: WHEN SIMILARITY DOES NOT SUFFICE.

    Science.gov (United States)

    Guney, Emre

    2017-01-01

    Repurposing existing drugs for new uses has attracted considerable attention over the past years. To identify potential candidates that could be repositioned for a new indication, many studies make use of chemical, target, and side effect similarity between drugs to train classifiers. Despite promising prediction accuracies of these supervised computational models, their use in practice, such as for rare diseases, is hindered by the assumption that there are already known and similar drugs for a given condition of interest. In this study, using publicly available data sets, we question the prediction accuracies of supervised approaches based on drug similarity when the drugs in the training and the test set are completely disjoint. We first build a Python platform to generate reproducible similarity-based drug repurposing models. Next, we show that, while a simple chemical, target, and side effect similarity based machine learning method can achieve good performance on the benchmark data set, the prediction performance drops sharply when the drugs in the folds of the cross validation are not overlapping and the similarity information within the training and test sets are used independently. These intriguing results suggest revisiting the assumptions underlying the validation scenarios of similarity-based methods and underline the need for unsupervised approaches to identify novel drug uses inside the unexplored pharmacological space. We make the digital notebook containing the Python code to replicate our analysis that involves the drug repurposing platform based on machine learning models and the proposed disjoint cross fold generation method freely available at github.com/emreg00/repurpose.

  12. Computer supported qualitative research

    CERN Document Server

    Reis, Luís; Sousa, Francislê; Moreira, António; Lamas, David

    2017-01-01

    This book contains an edited selection of the papers accepted for presentation and discussion at the first International Symposium on Qualitative Research (ISQR2016), held in Porto, Portugal, July 12th-14th, 2016. The book and the symposium features the four main application fields Education, Health, Social Sciences and Engineering and Technology and seven main subjects: Rationale and Paradigms of Qualitative Research (theoretical studies, critical reflection about epistemological dimensions, ontological and axiological); Systematization of approaches with Qualitative Studies (literature review, integrating results, aggregation studies, meta -analysis, meta- analysis of qualitative meta- synthesis, meta- ethnography); Qualitative and Mixed Methods Research (emphasis in research processes that build on mixed methodologies but with priority to qualitative approaches); Data Analysis Types (content analysis , discourse analysis , thematic analysis , narrative analysis , etc.); Innovative processes of Qualitative ...

  13. The reproducibility of random amplified polymorphic DNA (RAPD ...

    African Journals Online (AJOL)

    RAPD) profiles of Streptococcus thermophilus strains by using the polymerase chain reaction (PCR). Several factors can cause the amplification of false and non reproducible bands in the RAPD profiles. We tested three primers, OPI-02 MOD, ...

  14. Homotopy deform method for reproducing kernel space for ...

    Indian Academy of Sciences (India)

    2016-09-23

    Sep 23, 2016 ... Nonlinear differential equations; the homotopy deform method; the simplified reproducing kernel ... an equivalent integro differential equation. ... an algorithm for solving nonlinear multipoint BVPs by combining homotopy perturbation and variational iteration methods. Most recently, Duan and Rach [12].

  15. Homotopy deform method for reproducing kernel space for ...

    Indian Academy of Sciences (India)

    2016-09-23

    s12043-016-1269-8. Homotopy deform method for reproducing kernel space for nonlinear boundary value problems. MIN-QIANG XU. ∗ and YING-ZHEN LIN. School of Science, Zhuhai Campus, Beijing Institute of Technology, ...

  16. Transition questions in clinical practice - validity and reproducibility

    DEFF Research Database (Denmark)

    Lauridsen, Henrik Hein

    2008-01-01

    Transition questions in CLINICAL practice - validity and reproducibility Lauridsen HH1, Manniche C3, Grunnet-Nilsson N1, Hartvigsen J1,2 1   Clinical Locomotion Science, Institute of Sports Science and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark. e-mail: hlauridsen....... One way to determine the relevance of change scores is through the use of transition questions (TQ) that assesses patients’ retrospective perception of treatment effect. However, little is known about the validity and reproducibility of TQ’s. The objectives of this study were to explore aspects...... of construct validity and reproducibility of a TQ and make proposals for standardised use. One-hundred-and-ninety-one patients with low back pain and/or leg pain were followed over an 8-week period receiving 3 disability and 2 pain questionnaires together with a 7-point TQ. Reproducibility was determined using...

  17. Case Studies and Challenges in Reproducibility in the Computational Sciences

    OpenAIRE

    Arabas, Sylwester; Bareford, Michael R.; de Silva, Lakshitha R.; Gent, Ian P.; Gorman, Benjamin M.; Hajiarabderkani, Masih; Henderson, Tristan; Hutton, Luke; Konovalov, Alexander; Kotthoff, Lars; McCreesh, Ciaran; Nacenta, Miguel A.; Paul, Ruma R.; Petrie, Karen E. J.; Razaq, Abdul

    2014-01-01

    This paper investigates the reproducibility of computational science research and identifies key challenges facing the community today. It is the result of the First Summer School on Experimental Methodology in Computational Science Research (https://blogs.cs.st-andrews.ac.uk/emcsr2014/). First, we consider how to reproduce experiments that involve human subjects, and in particular how to deal with different ethics requirements at different institutions. Second, we look at whether parallel an...

  18. Adding an accredited exercise physiologist role to a new model of care at a secure extended care mental health service: a qualitative study.

    Science.gov (United States)

    Furness, Trentham; Hewavasam, Jude; Barnfield, Jakqui; McKenna, Brian; Joseph, Corey

    2018-04-01

    Accredited exercise physiologists (AEPs) are emerging as essential members of allied health in the management of non-communicable chronic diseases. People diagnosed with severe mental illness (SMI) are at greater risk of cardiovascular diseases. Secure extended care units (SECUs) provide treatment, supervision and support for people with SMI whose needs cannot be met adequately in the community. However, the role of AEPs in SECUs has not been described. Describe the processes and outcomes of adding an AEP to a new model of care at a SECU. An exploratory study with emphasis on qualitative data. Interviews with a purposive sample of SECU staff. Participants articulated concern about poor physical health of which two themes emerged (1) the development of the AEP role; a calculated gamble and (2) the practical application of the role. An AEP was identified as the role to best implement the organisations vision to improve physical health of people with SMI. Implementation and practical application of the role relied on an informed calculated gamble. Yet, once embedded in the service, the AEP role was able to capacity build among clinical staff, develop a treatment pathway, and implement consumer specific physical health interventions.

  19. Systematic heterogenization for better reproducibility in animal experimentation.

    Science.gov (United States)

    Richter, S Helene

    2017-08-31

    The scientific literature is full of articles discussing poor reproducibility of findings from animal experiments as well as failures to translate results from preclinical animal studies to clinical trials in humans. Critics even go so far as to talk about a "reproducibility crisis" in the life sciences, a novel headword that increasingly finds its way into numerous high-impact journals. Viewed from a cynical perspective, Fett's law of the lab "Never replicate a successful experiment" has thus taken on a completely new meaning. So far, poor reproducibility and translational failures in animal experimentation have mostly been attributed to biased animal data, methodological pitfalls, current publication ethics and animal welfare constraints. More recently, the concept of standardization has also been identified as a potential source of these problems. By reducing within-experiment variation, rigorous standardization regimes limit the inference to the specific experimental conditions. In this way, however, individual phenotypic plasticity is largely neglected, resulting in statistically significant but possibly irrelevant findings that are not reproducible under slightly different conditions. By contrast, systematic heterogenization has been proposed as a concept to improve representativeness of study populations, contributing to improved external validity and hence improved reproducibility. While some first heterogenization studies are indeed very promising, it is still not clear how this approach can be transferred into practice in a logistically feasible and effective way. Thus, further research is needed to explore different heterogenization strategies as well as alternative routes toward better reproducibility in animal experimentation.

  20. Spiking Neural Network With Distributed Plasticity Reproduces Cerebellar Learning in Eye Blink Conditioning Paradigms.

    Science.gov (United States)

    Antonietti, Alberto; Casellato, Claudia; Garrido, Jesús A; Luque, Niceto R; Naveros, Francisco; Ros, Eduardo; D' Angelo, Egidio; Pedrocchi, Alessandra

    2016-01-01

    In this study, we defined a realistic cerebellar model through the use of artificial spiking neural networks, testing it in computational simulations that reproduce associative motor tasks in multiple sessions of acquisition and extinction. By evolutionary algorithms, we tuned the cerebellar microcircuit to find out the near-optimal plasticity mechanism parameters that better reproduced human-like behavior in eye blink classical conditioning, one of the most extensively studied paradigms related to the cerebellum. We used two models: one with only the cortical plasticity and another including two additional plasticity sites at nuclear level. First, both spiking cerebellar models were able to well reproduce the real human behaviors, in terms of both "timing" and "amplitude", expressing rapid acquisition, stable late acquisition, rapid extinction, and faster reacquisition of an associative motor task. Even though the model with only the cortical plasticity site showed good learning capabilities, the model with distributed plasticity produced faster and more stable acquisition of conditioned responses in the reacquisition phase. This behavior is explained by the effect of the nuclear plasticities, which have slow dynamics and can express memory consolidation and saving. We showed how the spiking dynamics of multiple interactive neural mechanisms implicitly drive multiple essential components of complex learning processes.  This study presents a very advanced computational model, developed together by biomedical engineers, computer scientists, and neuroscientists. Since its realistic features, the proposed model can provide confirmations and suggestions about neurophysiological and pathological hypotheses and can be used in challenging clinical applications.

  1. Skin metabolism of aminophenols: Human keratinocytes as a suitable in vitro model to qualitatively predict the dermal transformation of 4-amino-2-hydroxytoluene in vivo

    International Nuclear Information System (INIS)

    Goebel, C.; Hewitt, N.J.; Kunze, G.; Wenker, M.; Hein, D.W.; Beck, H.; Skare, J.

    2009-01-01

    4-Amino-2-hydroxytolune (AHT) is an aromatic amine ingredient in oxidative hair colouring products. As skin contact occurs during hair dyeing, characterisation of dermal metabolism is important for the safety assessment of this chemical class. We have compared the metabolism of AHT in the human keratinocyte cell line HaCaT with that observed ex-vivo in human skin and in vivo (topical application versus oral (p.o.) and intravenous (i.v.) route). Three major metabolites of AHT were excreted, i.e. N-acetyl-AHT, AHT-sulfate and AHT-glucuronide. When 12.5 mg/kg AHT was applied topically, the relative amounts of each metabolite were altered such that N-acetyl-AHT product was the major metabolite (66% of the dose in comparison with 37% and 32% of the same applied dose after i.v. and p.o. administration, respectively). N-acetylated products were the only metabolites detected in HaCaT cells and ex-vivo whole human skin discs for AHT and p-aminophenol (PAP), an aromatic amine known to undergo N-acetylation in vivo. Since N-acetyltransferase 1 (NAT1) is the responsible enzyme, kinetics of AHT was further compared to the standard NAT1 substrate p-aminobenzoic acid (PABA) in the HaCaT model revealing similar values for K m and V max . In conclusion NAT1 dependent dermal N-acetylation of AHT represents a 'first-pass' metabolism effect in the skin prior to entering the systemic circulation. Since the HaCaT cell model represents a suitable in vitro assay for addressing the qualitative contribution of the skin to the metabolism of topically-applied aromatic amines it may contribute to a reduction in animal testing

  2. A coupled RL and transport model for mixed-field proton irradiation of Al2O3:C

    DEFF Research Database (Denmark)

    Greilich, Steffen; Edmund, Jens Morgenthaler; Jain, Mayank

    2008-01-01

    effects and inelastic hadronic scattering occur in proton therapy dosimetry. To investigate these aspects in relation to our system, we have combined simulation of particle transportation with a luminescence generation code based on track structure theory. The model was found to qualitatively reproduce...

  3. What Is Qualitative Research?

    Science.gov (United States)

    Otani, Takashi

    2017-01-01

    The article is an in-depth explanation of qualitative research, an approach increasingly prevalent among today's research communities. After discussing its present spread within the health sciences, the author addresses: 1. Its definition. 2. Its characteristics, as well as its theoretical and procedural background. 3. Its procedures. 4. Differences between qualitative and quantitative approaches. 5. Mixed methods incorporating quantitative research. And in conclusion: 6. The importance of establishing an epistemological perspective in qualitative research.

  4. How can we cope with the complexity of the environment? A "Learning by modelling" approach using qualitative reasoning for developing causal models and simulations with focus on Sustainable River Catchment Management

    Science.gov (United States)

    Poppe, Michaela; Zitek, Andreas; Salles, Paulo; Bredeweg, Bert; Muhar, Susanne

    2010-05-01

    The education system needs strategies to attract future scientists and practitioners. There is an alarming decline in the number of students choosing science subjects. Reasons for this include the perceived complexity and the lack of effective cognitive tools that enable learners to acquire the expertise in a way that fits its qualitative nature. The DynaLearn project utilises a "Learning by modelling" approach to deliver an individualised and engaging cognitive tool for acquiring conceptual knowledge. The modelling approach is based on qualitative reasoning, a research area within artificial intelligence, and allows for capturing and simulating qualitative systems knowledge. Educational activities within the DynaLearn software address topics at different levels of complexity, depending on the educational goals and settings. DynaLearn uses virtual characters in the learning environment as agents for engaging and motivating the students during their modelling exercise. The DynaLearn software represents an interactive learning environment in which learners are in control of their learning activities. The software is able to coach them individually based on their current progress, their knowledge needs and learning goals. Within the project 70 expert models on different environmental issues covering seven core topics (Earth Systems and Resources, The Living World, Human population, Land and Water Use, Energy Resources and Consumption, Pollution, and Global Changes) will be delivered. In the context of the core topic "Land and Water Use" the Institute of Hydrobiology and Aquatic Ecosystem Management has developed a model on Sustainable River Catchment Management. River systems with their catchments have been tremendously altered due to human pressures with serious consequences for the ecological integrity of riverine landscapes. The operation of hydropower plants, the implementation of flood protection measures, the regulation of flow and sediment regime and intensive

  5. Scientific Reproducibility in Biomedical Research: Provenance Metadata Ontology for Semantic Annotation of Study Description.

    Science.gov (United States)

    Sahoo, Satya S; Valdez, Joshua; Rueschman, Michael

    2016-01-01

    Scientific reproducibility is key to scientific progress as it allows the research community to build on validated results, protect patients from potentially harmful trial drugs derived from incorrect results, and reduce wastage of valuable resources. The National Institutes of Health (NIH) recently published a systematic guideline titled "Rigor and Reproducibility " for supporting reproducible research studies, which has also been accepted by several scientific journals. These journals will require published articles to conform to these new guidelines. Provenance metadata describes the history or origin of data and it has been long used in computer science to capture metadata information for ensuring data quality and supporting scientific reproducibility. In this paper, we describe the development of Provenance for Clinical and healthcare Research (ProvCaRe) framework together with a provenance ontology to support scientific reproducibility by formally modeling a core set of data elements representing details of research study. We extend the PROV Ontology (PROV-O), which has been recommended as the provenance representation model by World Wide Web Consortium (W3C), to represent both: (a) data provenance, and (b) process provenance. We use 124 study variables from 6 clinical research studies from the National Sleep Research Resource (NSRR) to evaluate the coverage of the provenance ontology. NSRR is the largest repository of NIH-funded sleep datasets with 50,000 studies from 36,000 participants. The provenance ontology reuses ontology concepts from existing biomedical ontologies, for example the Systematized Nomenclature of Medicine Clinical Terms (SNOMED CT), to model the provenance information of research studies. The ProvCaRe framework is being developed as part of the Big Data to Knowledge (BD2K) data provenance project.

  6. Validity in qualitative research.

    Science.gov (United States)

    Whittemore, R; Chase, S K; Mandle, C L

    2001-07-01

    Much contemporary dialogue has centered on the difficulty of establishing validity criteria in qualitative research. Developing validity standards in qualitative research is challenging because of the necessity to incorporate rigor and subjectivity as well as creativity into the scientific process. This article explores the extant issues related to the science and art of qualitative research and proposes a synthesis of contemporary viewpoints. A distinction between primary and secondary validity criteria in qualitative research is made with credibility, authenticity, criticality, and integrity identified as primary validity criteria and explicitness, vividness, creativity, thoroughness, congruence, and sensitivity identified as secondary validity criteria.

  7. Overview of qualitative research.

    Science.gov (United States)

    Grossoehme, Daniel H

    2014-01-01

    Qualitative research methods are a robust tool for chaplaincy research questions. Similar to much of chaplaincy clinical care, qualitative research generally works with written texts, often transcriptions of individual interviews or focus group conversations and seeks to understand the meaning of experience in a study sample. This article describes three common methodologies: ethnography, grounded theory, and phenomenology. Issues to consider relating to the study sample, design, and analysis are discussed. Enhancing the validity of the data, as well reliability and ethical issues in qualitative research are described. Qualitative research is an accessible way for chaplains to contribute new knowledge about the sacred dimension of people's lived experience.

  8. Qualitative versus quantitative methods in psychiatric research.

    Science.gov (United States)

    Razafsha, Mahdi; Behforuzi, Hura; Azari, Hassan; Zhang, Zhiqun; Wang, Kevin K; Kobeissy, Firas H; Gold, Mark S

    2012-01-01

    Qualitative studies are gaining their credibility after a period of being misinterpreted as "not being quantitative." Qualitative method is a broad umbrella term for research methodologies that describe and explain individuals' experiences, behaviors, interactions, and social contexts. In-depth interview, focus groups, and participant observation are among the qualitative methods of inquiry commonly used in psychiatry. Researchers measure the frequency of occurring events using quantitative methods; however, qualitative methods provide a broader understanding and a more thorough reasoning behind the event. Hence, it is considered to be of special importance in psychiatry. Besides hypothesis generation in earlier phases of the research, qualitative methods can be employed in questionnaire design, diagnostic criteria establishment, feasibility studies, as well as studies of attitude and beliefs. Animal models are another area that qualitative methods can be employed, especially when naturalistic observation of animal behavior is important. However, since qualitative results can be researcher's own view, they need to be statistically confirmed, quantitative methods. The tendency to combine both qualitative and quantitative methods as complementary methods has emerged over recent years. By applying both methods of research, scientists can take advantage of interpretative characteristics of qualitative methods as well as experimental dimensions of quantitative methods.

  9. Using prediction markets to estimate the reproducibility of scientific research.

    Science.gov (United States)

    Dreber, Anna; Pfeiffer, Thomas; Almenberg, Johan; Isaksson, Siri; Wilson, Brad; Chen, Yiling; Nosek, Brian A; Johannesson, Magnus

    2015-12-15

    Concerns about a lack of reproducibility of statistically significant results have recently been raised in many fields, and it has been argued that this lack comes at substantial economic costs. We here report the results from prediction markets set up to quantify the reproducibility of 44 studies published in prominent psychology journals and replicated in the Reproducibility Project: Psychology. The prediction markets predict the outcomes of the replications well and outperform a survey of market participants' individual forecasts. This shows that prediction markets are a promising tool for assessing the reproducibility of published scientific results. The prediction markets also allow us to estimate probabilities for the hypotheses being true at different testing stages, which provides valuable information regarding the temporal dynamics of scientific discovery. We find that the hypotheses being tested in psychology typically have low prior probabilities of being true (median, 9%) and that a "statistically significant" finding needs to be confirmed in a well-powered replication to have a high probability of being true. We argue that prediction markets could be used to obtain speedy information about reproducibility at low cost and could potentially even be used to determine which studies to replicate to optimally allocate limited resources into replications.

  10. Validation and reproducibility of an Australian caffeine food frequency questionnaire.

    Science.gov (United States)

    Watson, E J; Kohler, M; Banks, S; Coates, A M

    2017-08-01

    The aim of this study was to measure validity and reproducibility of a caffeine food frequency questionnaire (C-FFQ) developed for the Australian population. The C-FFQ was designed to assess average daily caffeine consumption using four categories of food and beverages including; energy drinks; soft drinks/soda; coffee and tea and chocolate (food and drink). Participants completed a seven-day food diary immediately followed by the C-FFQ on two consecutive days. The questionnaire was first piloted in 20 adults, and then, a validity/reproducibility study was conducted (n = 90 adults). The C-FFQ showed moderate correlations (r = .60), fair agreement (mean difference 63 mg) and reasonable quintile rankings indicating fair to moderate agreement with the seven-day food diary. To test reproducibility, the C-FFQ was compared to itself and showed strong correlations (r = .90), good quintile rankings and strong kappa values (κ = 0.65), indicating strong reproducibility. The C-FFQ shows adequate validity and reproducibility and will aid researchers in Australia to quantify caffeine consumption.

  11. Using prediction markets to estimate the reproducibility of scientific research

    Science.gov (United States)

    Dreber, Anna; Pfeiffer, Thomas; Almenberg, Johan; Isaksson, Siri; Wilson, Brad; Chen, Yiling; Nosek, Brian A.; Johannesson, Magnus

    2015-01-01

    Concerns about a lack of reproducibility of statistically significant results have recently been raised in many fields, and it has been argued that this lack comes at substantial economic costs. We here report the results from prediction markets set up to quantify the reproducibility of 44 studies published in prominent psychology journals and replicated in the Reproducibility Project: Psychology. The prediction markets predict the outcomes of the replications well and outperform a survey of market participants’ individual forecasts. This shows that prediction markets are a promising tool for assessing the reproducibility of published scientific results. The prediction markets also allow us to estimate probabilities for the hypotheses being true at different testing stages, which provides valuable information regarding the temporal dynamics of scientific discovery. We find that the hypotheses being tested in psychology typically have low prior probabilities of being true (median, 9%) and that a “statistically significant” finding needs to be confirmed in a well-powered replication to have a high probability of being true. We argue that prediction markets could be used to obtain speedy information about reproducibility at low cost and could potentially even be used to determine which studies to replicate to optimally allocate limited resources into replications. PMID:26553988

  12. Reproducibility2020: Progress and priorities [version 1; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Leonard P. Freedman

    2017-05-01

    Full Text Available The preclinical research process is a cycle of idea generation, experimentation, and reporting of results. The biomedical research community relies on the reproducibility of published discoveries to create new lines of research and to translate research findings into therapeutic applications. Since 2012, when scientists from Amgen reported that they were able to reproduce only 6 of 53 “landmark” preclinical studies, the biomedical research community began discussing the scale of the reproducibility problem and developing initiatives to address critical challenges. Global Biological Standards Institute (GBSI released the “Case for Standards” in 2013, one of the first comprehensive reports to address the rising concern of irreproducible biomedical research. Further attention was drawn to issues that limit scientific self-correction, including reporting and publication bias, underpowered studies, lack of open access to methods and data, and lack of clearly defined standards and guidelines in areas such as reagent validation. To evaluate the progress made towards reproducibility since 2013, GBSI identified and examined initiatives designed to advance quality and reproducibility. Through this process, we identified key roles for funders, journals, researchers and other stakeholders and recommended actions for future progress. This paper describes our findings and conclusions.

  13. Protocol for a process-oriented qualitative evaluation of the Waltham Forest and East London Collaborative (WELC) integrated care pioneer programme using the Researcher-in-Residence model.

    Science.gov (United States)

    Eyre, Laura; George, Bethan; Marshall, Martin

    2015-11-06

    The integration of health and social care in England is widely accepted as the answer to fragmentation, financial concerns and system inefficiencies, in the context of growing and ageing populations with increasingly complex needs. Despite an expanding body of literature, there is little evidence yet to suggest that integrated care can achieve the benefits that its advocates claim for it. Researchers have often adopted rationalist and technocratic approaches to evaluation, treating integration as an intervention rather than a process. Results have usually been of limited use to practitioners responsible for health and social care integration. There is, therefore, a need to broaden the evidence base, exploring not only what works but also how integrated care can most successfully be implemented and delivered. For this reason, we are carrying out a formative evaluation of the Waltham Forest and East London Collaborative (WELC) integrated care pioneer programme. Our expectation is that this will add value to the literature by focusing on the processes by which the vision and objectives of integrated care are translated through phases of development, implementation and delivery from a central to a local perspective, and from a strategic to an operational perspective. The qualitative and process-oriented evaluation uses an innovative participative approach-the Researcher-in-Residence model. The evaluation is underpinned by a critical ontology, an interpretive epistemology and a critical discourse analysis methodology. Data will be generated using interviews, observations and documentary gathering. Emerging findings will be interpreted and disseminated collaboratively with stakeholders, to enable the research to influence and optimise the effective implementation of integrated care across WELC. Presentations and publications will ensure that learning is shared as widely as possible. The study has received ethical approval from University College London's Research Ethics

  14. Youth-violence prevention in the aftermath of the San Diego East county school shootings: a qualitative assessment of community explanatory models.

    Science.gov (United States)

    Palinkas, Lawrence A; Prussing, Erica; Landsverk, John; Reznik, Vivian

    2003-01-01

    In March, 2001, 2 separate incidents of school shootings occurred within the same school district in San Diego's East County. To examine community explanatory models of the causes of the school shootings and strategies for preventing such events. A qualitative study was undertaken in 4 East County communities over a 6-month period following the 2 events. Semistructured interviews were conducted with 85 community residents identified through maximum variation sampling. Interview transcripts were analyzed by coding consensus, co-occurrence and comparison, using NVivo text analysis software. Four sets of theories as to the cause of these events were identified, based on the following: 1) unique or idiosyncratic characteristics of the 2 shooters (newcomer to community who was a victim of bullying, victim of child abuse with a history of mental illness), 2) universal factors (culture of violence, violence in the media), 3) family-centered characteristics (single-parent households, dysfunctional relationships), and 4) community-specific characteristics (reputation for social intolerance, widespread access to guns). Beliefs in family-centered and community-centered theories of etiology were associated with optimism in preventing such events from occurring in the future through increased recognition and response to problem behaviors, while beliefs in idiosyncratic or universal determinants of youth violence were associated with pessimistic assessments of prevention. In this community, youth-violence-prevention programs that focus on taking responsibility for recognizing and responding to problem behaviors in at-risk youth are more likely to gain community support and participation than programs that focus on increased security, surveillance, or behavior change.

  15. Evaluating Quantitative and Qualitative Traits of Promising Potato Clones and Commercial Cultivars Using the GGE Bi-plot and AMMI Models

    Directory of Open Access Journals (Sweden)

    D HassanPanah

    2014-07-01

    Full Text Available To evaluate quantitative and qualitative characteristics and stability of marketable tuber yield of 13 promising potato clones, along with three commercial cultivars (Agria, Marfona and Lady Rosetta as checks, an experiment was based on a randomized complete block design with four replications was carried out at the Agricultural and Natural Resources Research Station of Ardabil during 2011 and 2012. During the growing period and after harvest, attributes like number of main stem per plant, plant height, tuber number and weight per plant, total and marketable tuber yield, dry matter percentage, baking type, hollow heart, tuber inner ring and discoloration of raw tuber flesh after 24 hours were measured. Combined ANONA for quantitative traits showed that there were significant differences among promising clones as to total and marketable tuber yield, tuber number and weight per plant, plant height, mean tuber weight, number of main stem per plant and dry matter percentage and their interactions with year in total and marketable tuber yield and tuber number and weight per plant. The clones 396151-7, 397008-5, 397015-8, 397008-2 and 994001-4 were found to have higher total and marketable tuber yield, tuber number and weight per plant and mean tuber weight. These clones produced high and mid-uniform tuber, yellow skin color, yellow and white flesh color, oval round and round tuber shape, mid and shallow eyes, with no hollow heart, tuber inner crack and tuber inner ring, mid-late maturity and mid and high dry matter percentage as compared with control and other clones. In this experiment, GGE Bi-plot and AMMI models were found to be proper methods for selection of 397008-2, 397008-5 and 994001-4 as being high marketable and stable yielding clones.

  16. Reproducibility of bracket positioning in the indirect bonding technique.

    Science.gov (United States)

    Nichols, Dale A; Gardner, Gary; Carballeyra, Alain D

    2013-11-01

    Current studies have compared indirect bonding with direct placement of orthodontic brackets; many of these have shown that indirect bonding is generally a more accurate technique. However, the reproducibility of an indirect bonding setup by an orthodontist has yet to be described in the literature. Using cone-beam computed tomography and computer-assisted modeling software, we evaluated the consistency of orthodontists in placing orthodontic brackets at different times. Five orthodontists with experience in indirect bonding were selected to place brackets on 10 different casts at 3 time periods (n = 30 per orthodontist). Each participant completed an initial indirect bonding setup on each cast; subsequent bracket placements were completed twice at monthly intervals for comparison with the initial setup. The casts were scanned using an iCAT cone-beam computed tomography scanner (Imaging Sciences International, Hatfield, Pa) and imported into Geomagic Studio software (Geomagic, Research Triangle Park, NC) for superimposition and analysis. The scans for each time period were superimposed on the initial setup in the imaging software, and differences between bracket positions were calculated. For each superimposition, the measurements recorded were the greatest discrepancies between individual brackets as well as the mean discrepancies and standard deviations between all brackets on each cast. Single-factor and repeated-measure analysis of variance showed no statistically significant differences between time points of each orthodontist, or among the orthodontists for the parameters measured. The mean discrepancy was 0.1 mm for each 10-bracket indirect bonding setup. Orthodontists are consistent in selecting bracket positions for an indirect bonding setup at various time periods. Copyright © 2013 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

  17. Reproducible preclinical research-Is embracing variability the answer?

    Science.gov (United States)

    Karp, Natasha A

    2018-03-01

    Translational failures and replication issues of published research are undermining preclinical research and, if the outcomes are questionable, raise ethical implications over the continued use of animals. Standardization of procedures, environmental conditions, and genetic background has traditionally been proposed as the gold standard approach, as it reduces variability, thereby enhancing sensitivity and supporting reproducibility when the environment is defined precisely. An alternative view is that standardization can identify idiosyncratic effects and hence decrease reproducibility. In support of this alternative view, Voelkl and colleagues present evidence from resampling a large quantity of research data exploring a variety of treatments. They demonstrate that by implementing multi-laboratory experiments with as few as two sites, we can increase reproducibility by embracing variation without increasing the sample size.

  18. Dysplastic naevus: histological criteria and their inter-observer reproducibility.

    Science.gov (United States)

    Hastrup, N; Clemmensen, O J; Spaun, E; Søndergaard, K

    1994-06-01

    Forty melanocytic lesions were examined in a pilot study, which was followed by a final series of 100 consecutive melanocytic lesions, in order to evaluate the inter-observer reproducibility of the histological criteria proposed for the dysplastic naevus. The specimens were examined in a blind fashion by four observers. Analysis by kappa statistics showed poor reproducibility of nuclear features, while reproducibility of architectural features was acceptable, improving in the final series. Consequently, we cannot apply the combined criteria of cytological and architectural features with any confidence in the diagnosis of dysplastic naevus, and, until further studies have documented that architectural criteria alone will suffice in the diagnosis of dysplastic naevus, we, as pathologists, shall avoid this term.

  19. Progress toward openness, transparency, and reproducibility in cognitive neuroscience.

    Science.gov (United States)

    Gilmore, Rick O; Diaz, Michele T; Wyble, Brad A; Yarkoni, Tal

    2017-05-01

    Accumulating evidence suggests that many findings in psychological science and cognitive neuroscience may prove difficult to reproduce; statistical power in brain imaging studies is low and has not improved recently; software errors in analysis tools are common and can go undetected for many years; and, a few large-scale studies notwithstanding, open sharing of data, code, and materials remain the rare exception. At the same time, there is a renewed focus on reproducibility, transparency, and openness as essential core values in cognitive neuroscience. The emergence and rapid growth of data archives, meta-analytic tools, software pipelines, and research groups devoted to improved methodology reflect this new sensibility. We review evidence that the field has begun to embrace new open research practices and illustrate how these can begin to address problems of reproducibility, statistical power, and transparency in ways that will ultimately accelerate discovery. © 2017 New York Academy of Sciences.

  20. Getting added value from using qualitative research with randomized controlled trials: a qualitative interview study

    Science.gov (United States)

    2014-01-01

    Background Qualitative research is undertaken with randomized controlled trials of health interventions. Our aim was to explore the perceptions of researchers with experience of this endeavour to understand the added value of qualitative research to the trial in practice. Methods A telephone semi-structured interview study with 18 researchers with experience of undertaking the trial and/or the qualitative research. Results Interviewees described the added value of qualitative research for the trial, explaining how it solved problems at the pretrial stage, explained findings, and helped to increase the utility of the evidence generated by the trial. From the interviews, we identified three models of relationship of the qualitative research to the trial. In ‘the peripheral’ model, the trial was an opportunity to undertake qualitative research, with no intention that it would add value to the trial. In ‘the add-on’ model, the qualitative researcher understood the potential value of the qualitative research but it was viewed as a separate and complementary endeavour by the trial lead investigator and wider team. Interviewees described how this could limit the value of the qualitative research to the trial. Finally ‘the integral’ model played out in two ways. In ‘integral-in-theory’ studies, the lead investigator viewed the qualitative research as essential to the trial. However, in practice the qualitative research was under-resourced relative to the trial, potentially limiting its ability to add value to the trial. In ‘integral-in-practice’ studies, interviewees described how the qualitative research was planned from the beginning of the study, senior qualitative expertise was on the team from beginning to end, and staff and time were dedicated to the qualitative research. In these studies interviewees described the qualitative research adding value to the trial although this value was not necessarily visible beyond the original research team due

  1. Getting added value from using qualitative research with randomized controlled trials: a qualitative interview study.

    Science.gov (United States)

    O'Cathain, Alicia; Goode, Jackie; Drabble, Sarah J; Thomas, Kate J; Rudolph, Anne; Hewison, Jenny

    2014-06-09

    Qualitative research is undertaken with randomized controlled trials of health interventions. Our aim was to explore the perceptions of researchers with experience of this endeavour to understand the added value of qualitative research to the trial in practice. A telephone semi-structured interview study with 18 researchers with experience of undertaking the trial and/or the qualitative research. Interviewees described the added value of qualitative research for the trial, explaining how it solved problems at the pretrial stage, explained findings, and helped to increase the utility of the evidence generated by the trial. From the interviews, we identified three models of relationship of the qualitative research to the trial. In 'the peripheral' model, the trial was an opportunity to undertake qualitative research, with no intention that it would add value to the trial. In 'the add-on' model, the qualitative researcher understood the potential value of the qualitative research but it was viewed as a separate and complementary endeavour by the trial lead investigator and wider team. Interviewees described how this could limit the value of the qualitative research to the trial. Finally 'the integral' model played out in two ways. In 'integral-in-theory' studies, the lead investigator viewed the qualitative research as essential to the trial. However, in practice the qualitative research was under-resourced relative to the trial, potentially limiting its ability to add value to the trial. In 'integral-in-practice' studies, interviewees described how the qualitative research was planned from the beginning of the study, senior qualitative expertise was on the team from beginning to end, and staff and time were dedicated to the qualitative research. In these studies interviewees described the qualitative research adding value to the trial although this value was not necessarily visible beyond the original research team due to the challenges of publishing this research

  2. Reproducibility of clinical research in critical care: a scoping review.

    Science.gov (United States)

    Niven, Daniel J; McCormick, T Jared; Straus, Sharon E; Hemmelgarn, Brenda R; Jeffs, Lianne; Barnes, Tavish R M; Stelfox, Henry T

    2018-02-21

    The ability to reproduce experiments is a defining principle of science. Reproducibility of clinical research has received relatively little scientific attention. However, it is important as it may inform clinical practice, research agendas, and the design of future studies. We used scoping review methods to examine reproducibility within a cohort of randomized trials examining clinical critical care research and published in the top general medical and critical care journals. To identify relevant clinical practices, we searched the New England Journal of Medicine, The Lancet, and JAMA for randomized trials published up to April 2016. To identify a comprehensive set of studies for these practices, included articles informed secondary searches within other high-impact medical and specialty journals. We included late-phase randomized controlled trials examining therapeutic clinical practices in adults admitted to general medical-surgical or specialty intensive care units (ICUs). Included articles were classified using a reproducibility framework. An original study was the first to evaluate a clinical practice. A reproduction attempt re-evaluated that practice in a new set of participants. Overall, 158 practices were examined in 275 included articles. A reproduction attempt was identified for 66 practices (42%, 95% CI 33-50%). Original studies reported larger effects than reproduction attempts (primary endpoint, risk difference 16.0%, 95%