WorldWideScience

Sample records for models comparing activities

  1. Comparative molecular modelling of biologically active sterols

    Science.gov (United States)

    Baran, Mariusz; Mazerski, Jan

    2015-04-01

    Membrane sterols are targets for a clinically important antifungal agent - amphotericin B. The relatively specific antifungal action of the drug is based on a stronger interaction of amphotericin B with fungal ergosterol than with mammalian cholesterol. Conformational space occupied by six sterols has been defined using the molecular dynamics method to establish if the conformational features correspond to the preferential interaction of amphotericin B with ergosterol as compared with cholesterol. The compounds studied were chosen on the basis of structural features characteristic for cholesterol and ergosterol and on available experimental data on the ability to form complexes with the antibiotic. Statistical analysis of the data obtained has been performed. The results show similarity of the conformational spaces occupied by all the sterols tested. This suggests that the conformational differences of sterol molecules are not the major feature responsible for the differential sterol - drug affinity.

  2. Activity Modelling and Comparative Evaluation of WSN MAC Security Attacks

    DEFF Research Database (Denmark)

    Pawar, Pranav M.; Nielsen, Rasmus Hjorth; Prasad, Neeli R.

    2012-01-01

    and initiate security attacks that disturb the normal functioning of the network in a severe manner. Such attacks affect the performance of the network by increasing the energy consumption, by reducing throughput and by inducing long delays. Of all existing WSN attacks, MAC layer attacks are considered....... The second aim of the paper is to simulate these attacks on hybrid MAC mechanisms, which shows the performance degradation of aWSN under the considered attacks. The modelling and implementation of the security attacks give an actual view of the network which can be useful in further investigating secure......Applications of wireless sensor networks (WSNs) are growing tremendously in the domains of habitat, tele-health, industry monitoring, vehicular networks, home automation and agriculture. This trend is a strong motivation for malicious users to increase their focus on WSNs and to develop...

  3. Scaling laws of coronal loops compared to a 3D MHD model of an Active Region

    CERN Document Server

    Bourdin, Philippe-A; Peter, Hardi

    2016-01-01

    Context. The structure and heating of coronal loops are investigated since decades. Established scaling laws relate fundamental quantities like the loop apex temperature, pressure, length, and the coronal heating. Aims. We test such scaling laws against a large-scale 3D MHD model of the Solar corona, which became feasible with nowadays high-performance computing. Methods. We drive an active region simulation a with photospheric observations and found strong similarities to the observed coronal loops in X-rays and EUV wavelength. A 3D reconstruction of stereoscopic observations showed that our model loops have a realistic spatial structure. We compare scaling laws to our model data extracted along an ensemble of field lines. Finally, we fit a new scaling law that represents well hot loops and also cooler structures, which was not possible before only based on observations. Results. Our model data gives some support for scaling laws that were established for hot and EUV-emissive coronal loops. For the RTV scali...

  4. Comparative Analysis of Probabilistic Models for Activity Recognition with an Instrumented Walker

    CERN Document Server

    Omar, Farheen; Truszkowski, Jakub; Poupart, Pascal; Tung, James; Caine, Allen

    2012-01-01

    Rollating walkers are popular mobility aids used by older adults to improve balance control. There is a need to automatically recognize the activities performed by walker users to better understand activity patterns, mobility issues and the context in which falls are more likely to happen. We design and compare several techniques to recognize walker related activities. A comprehensive evaluation with control subjects and walker users from a retirement community is presented.

  5. Protein Models Comparator

    CERN Document Server

    Widera, Paweł

    2011-01-01

    The process of comparison of computer generated protein structural models is an important element of protein structure prediction. It has many uses including model quality evaluation, selection of the final models from a large set of candidates or optimisation of parameters of energy functions used in template free modelling and refinement. Although many protein comparison methods are available online on numerous web servers, their ability to handle a large scale model comparison is often very limited. Most of the servers offer only a single pairwise structural comparison, and they usually do not provide a model-specific comparison with a fixed alignment between the models. To bridge the gap between the protein and model structure comparison we have developed the Protein Models Comparator (pm-cmp). To be able to deliver the scalability on demand and handle large comparison experiments the pm-cmp was implemented "in the cloud". Protein Models Comparator is a scalable web application for a fast distributed comp...

  6. The comparative study of a laccase-natural clinoptilolite-based catalyst activity and free laccase activity on model compounds.

    Science.gov (United States)

    Donati, Enrica; Polcaro, Chiara M; Ciccioli, Piero; Galli, Emanuela

    2015-05-30

    For the first time a laccase from Trametes versicolor was immobilized on a natural clinoptilolite with Si/Al=5 to obtain a biocatalyst for environmental applications. Immobilization procedures exploiting adsorption and covalent binding were both tested, and only the last provided enough activity for practical applications. The optimal conditions for the immobilization of the enzyme on the support and the kinetic parameters for the free and covalent bonded laccase were determined. The laccase bonded to the zeolitic support showed a lower activity than the free laccase, but the pH and thermal stability were greater. 20 mg of dry biocatalyst containing 1 U of laccase were able to remove in 50h 73-78% of 2-chlorophenol and 2,4-dichlorophenol in relatively concentrated aqueous solutions (100 μmol L(-1)).

  7. Mindfulness training alters emotional memory recall compared to active controls: support for an emotional information processing model of mindfulness

    Directory of Open Access Journals (Sweden)

    Doug eRoberts-Wolfe

    2012-02-01

    Full Text Available Objectives: While mindfulness-based interventions have received widespread application in both clinical and non-clinical populations, the mechanism by which mindfulness meditation improves well-being remains elusive. One possibility is that mindfulness training alters the processing of emotional information, similar to prevailing cognitive models of depression and anxiety. The aim of this study was to investigating the effects of mindfulness training on emotional information processing (i.e. memory biases in relation to both clinical symptomatology and well-being in comparison to active control conditions.Methods: Fifty-eight university students (28 female, age = 20.1 ± 2.7 years participated in either a 12-week course containing a "meditation laboratory" or an active control course with similar content or experiential practice laboratory format (music. Participants completed an emotional word recall task and self-report questionnaires of well-being and clinical symptoms before and after the 12-week course.Results: Meditators showed greater increases in positive word recall compared to controls F(1, 56 = 6.6, p = .02. The meditation group increased significantly more on measures of well-being [F(1, 56 = 6.6, p = .01], with a marginal decrease in depression and anxiety [(F(1, 56 = 3.0, p = .09] compared to controls. Increased positive word recall was associated with increased psychological well-being [r = 0.31, p = .02] and decreased clinical symptoms [r = -0.29, p = .03].Conclusion: Mindfulness training was associated with greater improvements in processing efficiency for positively valenced stimuli than active control conditions. This change in emotional information processing was associated with improvements in psychological well-being and less depression and anxiety. These data suggest that mindfulness training may improve well-being via changes in emotional information processing.

  8. Comparing root architectural models

    Science.gov (United States)

    Schnepf, Andrea; Javaux, Mathieu; Vanderborght, Jan

    2017-04-01

    Plant roots play an important role in several soil processes (Gregory 2006). Root architecture development determines the sites in soil where roots provide input of carbon and energy and take up water and solutes. However, root architecture is difficult to determine experimentally when grown in opaque soil. Thus, root architectural models have been widely used and been further developed into functional-structural models that are able to simulate the fate of water and solutes in the soil-root system (Dunbabin et al. 2013). Still, a systematic comparison of the different root architectural models is missing. In this work, we focus on discrete root architecture models where roots are described by connected line segments. These models differ (a) in their model concepts, such as the description of distance between branches based on a prescribed distance (inter-nodal distance) or based on a prescribed time interval. Furthermore, these models differ (b) in the implementation of the same concept, such as the time step size, the spatial discretization along the root axes or the way stochasticity of parameters such as root growth direction, growth rate, branch spacing, branching angles are treated. Based on the example of two such different root models, the root growth module of R-SWMS and RootBox, we show the impact of these differences on simulated root architecture and aggregated information computed from this detailed simulation results, taking into account the stochastic nature of those models. References Dunbabin, V.M., Postma, J.A., Schnepf, A., Pagès, L., Javaux, M., Wu, L., Leitner, D., Chen, Y.L., Rengel, Z., Diggle, A.J. Modelling root-soil interactions using three-dimensional models of root growth, architecture and function (2013) Plant and Soil, 372 (1-2), pp. 93 - 124. Gregory (2006) Roots, rhizosphere and soil: the route to a better understanding of soil science? European Journal of Soil Science 57: 2-12.

  9. Mindfulness training alters emotional memory recall compared to active controls: support for an emotional information processing model of mindfulness.

    Science.gov (United States)

    Roberts-Wolfe, Douglas; Sacchet, Matthew D; Hastings, Elizabeth; Roth, Harold; Britton, Willoughby

    2012-01-01

    While mindfulness-based interventions have received widespread application in both clinical and non-clinical populations, the mechanism by which mindfulness meditation improves well-being remains elusive. One possibility is that mindfulness training alters the processing of emotional information, similar to prevailing cognitive models of depression and anxiety. The aim of this study was to investigate the effects of mindfulness training on emotional information processing (i.e., memory) biases in relation to both clinical symptomatology and well-being in comparison to active control conditions. Fifty-eight university students (28 female, age = 20.1 ± 2.7 years) participated in either a 12-week course containing a "meditation laboratory" or an active control course with similar content or experiential practice laboratory format (music). Participants completed an emotional word recall task and self-report questionnaires of well-being and clinical symptoms before and after the 12-week course. Meditators showed greater increases in positive word recall compared to controls [F(1, 56) = 6.6, p = 0.02]. The meditation group increased significantly more on measures of well-being [F(1, 56) = 6.6, p = 0.01], with a marginal decrease in depression and anxiety [F(1, 56) = 3.0, p = 0.09] compared to controls. Increased positive word recall was associated with increased psychological well-being (r = 0.31, p = 0.02) and decreased clinical symptoms (r = -0.29, p = 0.03). Mindfulness training was associated with greater improvements in processing efficiency for positively valenced stimuli than active control conditions. This change in emotional information processing was associated with improvements in psychological well-being and less depression and anxiety. These data suggest that mindfulness training may improve well-being via changes in emotional information processing. Future research with a fully randomized design will be

  10. The Combined Strength of Thermodynamics and Comparative Planetology: Application of Activity Models to Core Formation in Terrestrial Bodies

    Science.gov (United States)

    Righter, K.; Pando, K. M.; Danielson, L. R.

    2015-01-01

    Recent models for accretion of terrestrial bodies involve metal-silicate equilibrium as the metallic core formed during growth. Most elements considered are either refractory or well studied elements for which effects of pressure, temperature, oxygen fugacity, and metallic liquid composition are well known. There are a large number of elements that are both siderophile and volatile, whose fate in such models is unknown, largely due to a lack of data at comparable conditions and com-positions (FeNi core with light elements such as S, C, Si, and O). We have focused on Ge, In, As, Sb and determined the effect of Si and C on metal-silicate partitioning, and developed a thermo-dynamic model that allows application of these new data to a wide range of planetary bodies. New experiments: We have previously carried out experiments with FeSi metallic liquid at C-saturated conditions at 1600 and 1800 C [4]. In a new series of experiments we investigate the effect of Si in carbon-free systems at 1600 C for comparison. Experiments were carried out at 1 GPa in MgO capsules using the same basaltic starting composition as in previous studies. The MgO capsule reacts with the silicate melt to form more MgO-rich liquids that have 22-26 wt% MgO. Experimental met-als and silicates were analyzed using a combination of electron microprobe analysis and laser ablation ICP-MS. Results: The new results can be interpreted by considering Ge as an example, in the simple exchange equilibrium Fe + GeO = FeO + Ge, where the equilibrium constant Kd can be examined as a function of Si content of the metal. The slope of lnKd vs. (1-XSi) for this new series allows derivation of the epsilon interaction parameter for each of these four elements and Si (both C-saturated and C-free).All four elements have positive epsilon values, indicating that Si causes a decrease in the partition coefficients; values are 6.6, 6.5, 27.8 and 25.2 for In, Ge, As, and Sb, respectively, at 1 GPa and 1600 C. As an example of

  11. Comparing and modeling organic micro-pollutant adsorption onto powdered activated carbon in different drinking waters and WWTP effluents.

    Science.gov (United States)

    Zietzschmann, Frederik; Aschermann, Geert; Jekel, Martin

    2016-10-01

    The adsorption of organic micro-pollutants (OMP) onto powdered activated carbon (PAC) was compared between regionally different waters within two groups, namely five drinking waters and seven wastewater treatment plant (WWTP) effluents. In all waters, OMP were spiked to adjust similar ratios of the initial OMP and DOC concentrations (c0,OMP/c0,DOC). PAC was dosed specific to the respective DOC (e.g. 2 mg PAC/per mg DOC). Liquid chromatography with online carbon detection shows differences of the background organic matter (BOM) compositions. The OMP removals at given DOC-specific PAC doses vary by ±15% (drinking waters) and ±10% (WWTP effluents). Similar BOM-induced adsorption competition in the waters of the respective group results in overall relationships between the PAC loadings and the liquid phase concentrations of each OMP (in the case of strong adsorbates). Weaker adsorbates show no overall relationships because of the strong BOM-induced adsorption competition near the initial OMP concentration. Correlations between OMP removals and UV254 removals were independent of the water (within the respective group). The equivalent background compound (EBC) model was applied to the experimental data. Using global EBC Freundlich coefficients, the initial EBC concentration correlates with the DOC (both water groups separately) and the low molecular weight (LMW) organics concentrations (all waters combined). With these correlations, the EBC could be initialized by using the DOC or the LMW organics concentration of additional drinking water, WWTP effluent, and surface water samples.

  12. Autologous Stem Cell Transplantation in Patients With Multiple Myeloma: An Activity-based Costing Analysis, Comparing a Total Inpatient Model Versus an Early Discharge Model.

    Science.gov (United States)

    Martino, Massimo; Console, Giuseppe; Russo, Letteria; Meliado', Antonella; Meliambro, Nicola; Moscato, Tiziana; Irrera, Giuseppe; Messina, Giuseppe; Pontari, Antonella; Morabito, Fortunato

    2017-08-01

    Activity-based costing (ABC) was developed and advocated as a means of overcoming the systematic distortions of traditional cost accounting. We calculated the cost of high-dose chemotherapy and autologous stem cell transplantation (ASCT) in patients with multiple myeloma using the ABC method, through 2 different care models: the total inpatient model (TIM) and the early-discharge outpatient model (EDOM) and compared this with the approved diagnosis related-groups (DRG) Italian tariffs. The TIM and EDOM models involved a total cost of €28,615.15 and €16,499.43, respectively. In the TIM model, the phase with the greatest economic impact was the posttransplant (recovery and hematologic engraftment) with 36.4% of the total cost, whereas in the EDOM model, the phase with the greatest economic impact was the pretransplant (chemo-mobilization, apheresis procedure, cryopreservation, and storage) phase, with 60.4% of total expenses. In an analysis of each episode, the TIM model comprised a higher absorption than the EDOM. In particular, the posttransplant represented 36.4% of the total costs in the TIM and 17.7% in EDOM model, respectively. The estimated reduction in cost per patient using an EDOM model was over €12,115.72. The repayment of the DRG in Calabrian Region for the ASCT procedure is €59,806. Given the real cost of the transplant, the estimated cost saving per patient is €31,190.85 in the TIM model and €43,306.57 in the EDOM model. In conclusion, the actual repayment of the DRG does not correspond to the real cost of the ASCT procedure in Italy. Moreover, using the EDOM, the cost of ASCT is approximately the half of the TIM model. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Variance components models for physical activity with age as modifier: a comparative twin study in seven countries

    DEFF Research Database (Denmark)

    Vink, Jacqueline M; Boomsma, Dorret I; Medland, Sarah E;

    2011-01-01

    Physical activity is influenced by genetic factors whose expression may change with age. We employed an extension to the classical twin model that allows a modifier variable, age, to interact with the effects of the latent genetic and environmental factors. The model was applied to self-reported ......Physical activity is influenced by genetic factors whose expression may change with age. We employed an extension to the classical twin model that allows a modifier variable, age, to interact with the effects of the latent genetic and environmental factors. The model was applied to self......-reported data from twins aged 19 to 50 from seven countries that collaborated in the GenomEUtwin project: Australia, Denmark, Finland, Norway, Netherlands, Sweden and United Kingdom. Results confirmed the importance of genetic influences on physical activity in all countries and showed an age-related decrease...... into account when exploring the genetic and environmental contribution to physical activity. It also suggests that the power of genome-wide association studies to identify the genetic variants contributing to physical activity may be larger in young adult cohorts....

  14. Angiotensin-converting enzyme-2 (ACE2): comparative modeling of the active site, specificity requirements, and chloride dependence.

    Science.gov (United States)

    Guy, Jodie L; Jackson, Richard M; Acharya, K Ravi; Sturrock, Edward D; Hooper, Nigel M; Turner, Anthony J

    2003-11-18

    Angiotensin-converting enzyme 2 (ACE2), a homologue of ACE, represents a new and potentially important target in cardio-renal disease. A model of the active site of ACE2, based on the crystal structure of testicular ACE, has been developed and indicates that the catalytic mechanism of ACE2 resembles that of ACE. Structural differences exist between the active site of ACE (dipeptidyl carboxypeptidase) and ACE2 (carboxypeptidase) that are responsible for the differences in specificity. The main differences occur in the ligand-binding pockets, particularly at the S2' subsite and in the binding of the peptide carboxy-terminus. The model explains why the classical ACE inhibitor lisinopril is unable to bind to ACE2. On the basis of the ability of ACE2 to cleave a variety of biologically active peptides, a consensus sequence of Pro-X-Pro-hydrophobic/basic for the protease specificity of ACE2 has been defined that is supported by the ACE2 model. The dipeptide, Pro-Phe, completely inhibits ACE2 activity at 180 microM with angiotensin II as the substrate. As with ACE, the chloride dependence of ACE2 is substrate-specific such that the hydrolysis of angiotensin I and the synthetic peptide substrate, Mca-APK(Dnp), are activated in the presence of chloride ions, whereas the cleavage of angiotensin II is inhibited. The ACE2 model is also suggestive of a possible mechanism for chloride activation. The structural insights provided by these analyses for the differences in inhibition pattern and substrate specificity among ACE and its homologue ACE2 and for the chloride dependence of ACE/ACE2 activity are valuable in understanding the function and regulation of ACE2.

  15. An analysis of controls on fire activity in boreal Canada: comparing models built with different temporal resolutions

    Science.gov (United States)

    Marc-Andre Parisien; Sean A. Parks; Meg A. Krawchuk; John M. Little; Mike D. Flannigan; Lynn M. Gowman; Max A. Moritz

    2014-01-01

    Fire regimes of the Canadian boreal forest are driven by certain environmental factors that are highly variable from year to year (e.g., temperature, precipitation) and others that are relatively stable (e.g., land cover, topography). Studies examining the relative influence of these environmental drivers on fire activity suggest that models making explicit use of...

  16. Comparative modeling and molecular dynamics suggest high carboxylase activity of the Cyanobium sp. CACIAM14 RbcL protein.

    Science.gov (United States)

    Siqueira, Andrei Santos; Lima, Alex Ranieri Jerônimo; Dall'Agnol, Leonardo Teixeira; de Azevedo, Juliana Simão Nina; da Silva Gonçalves Vianez, João Lídio; Gonçalves, Evonnildo Costa

    2016-03-01

    Rubisco catalyzes the first step reaction in the carbon fixation pathway, bonding atmospheric CO2/O2 to ribulose 1,5-bisphosphate; it is therefore considered one of the most important enzymes in the biosphere. Genetic modifications to increase the carboxylase activity of rubisco are a subject of great interest to agronomy and biotechnology, since this could increase the productivity of biomass in plants, algae and cyanobacteria and give better yields in crops and biofuel production. Thus, the aim of this study was to characterize in silico the catalytic domain of the rubisco large subunit (rbcL gene) of Cyanobium sp. CACIAM14, and identify target sites to improve enzyme affinity for ribulose 1,5-bisphosphate. A three-dimensional model was built using MODELLER 9.14, molecular dynamics was used to generate a 100 ns trajectory by AMBER12, and the binding free energy was calculated using MM-PBSA, MM-GBSA and SIE methods with alanine scanning. The model obtained showed characteristics of form-I rubisco, with 15 beta sheets and 19 alpha helices, and maintained the highly conserved catalytic site encompassing residues Lys175, Lys177, Lys201, Asp203, and Glu204. The binding free energy of the enzyme-substrate complexation of Cyanobium sp. CACIAM14 showed values around -10 kcal mol(-1) using the SIE method. The most important residues for the interaction with ribulose 1,5-bisphosphate were Arg295 followed by Lys334. The generated model was successfully validated, remaining stable during the whole simulation, and demonstrated characteristics of enzymes with high carboxylase activity. The binding analysis revealed candidates for directed mutagenesis sites to improve rubisco's affinity.

  17. Comparing different dynamic stall models

    Energy Technology Data Exchange (ETDEWEB)

    Holierhoek, J.G. [Unit Wind Energy, Energy research Centre of the Netherlands, ZG, Petten (Netherlands); De Vaal, J.B.; Van Zuijlen, A.H.; Bijl, H. [Aerospace Engineering, Delft University of Technology, Delft (Netherlands)

    2012-07-16

    The dynamic stall phenomenon and its importance for load calculations and aeroelastic simulations is well known. Different models exist to model the effect of dynamic stall; however, a systematic comparison is still lacking. To investigate if one is performing better than another, three models are used to simulate the Ohio State University measurements and a set of data from the National Aeronautics and Space Administration Ames experimental study of dynamic stall and compare results. These measurements were at conditions and for aerofoils that are typical for wind turbines, and the results are publicly available. The three selected dynamic stall models are the ONERA model, the Beddoes-Leishman model and the Snel model. The simulations show that there are still significant differences between measurements and models and that none of the models is significantly better in all cases than the other models. Especially in the deep stall regime, the accuracy of each of the dynamic stall models is limited.

  18. Comparative Protein Structure Modeling Using MODELLER.

    Science.gov (United States)

    Webb, Benjamin; Sali, Andrej

    2016-06-20

    Comparative protein structure modeling predicts the three-dimensional structure of a given protein sequence (target) based primarily on its alignment to one or more proteins of known structure (templates). The prediction process consists of fold assignment, target-template alignment, model building, and model evaluation. This unit describes how to calculate comparative models using the program MODELLER and how to use the ModBase database of such models, and discusses all four steps of comparative modeling, frequently observed errors, and some applications. Modeling lactate dehydrogenase from Trichomonas vaginalis (TvLDH) is described as an example. The download and installation of the MODELLER software is also described. © 2016 by John Wiley & Sons, Inc.

  19. Activated sludge model 2d calibration with full-scale WWTP data: comparing model parameter identifiability with influent and operational uncertainty.

    Science.gov (United States)

    Machado, Vinicius Cunha; Lafuente, Javier; Baeza, Juan Antonio

    2014-07-01

    The present work developed a model for the description of a full-scale wastewater treatment plant (WWTP) (Manresa, Catalonia, Spain) for further plant upgrades based on the systematic parameter calibration of the activated sludge model 2d (ASM2d) using a methodology based on the Fisher information matrix. The influent was characterized for the application of the ASM2d and the confidence interval of the calibrated parameters was also assessed. No expert knowledge was necessary for model calibration and a huge available plant database was converted into more useful information. The effect of the influent and operating variables on the model fit was also studied using these variables as calibrating parameters and keeping the ASM2d kinetic and stoichiometric parameters, which traditionally are the calibration parameters, at their default values. Such an "inversion" of the traditional way of model fitting allowed evaluating the sensitivity of the main model outputs regarding the influent and the operating variables changes. This new approach is able to evaluate the capacity of the operational variables used by the WWTP feedback control loops to overcome external disturbances in the influent and kinetic/stoichiometric model parameters uncertainties. In addition, the study of the influence of operating variables on the model outputs provides useful information to select input and output variables in decentralized control structures.

  20. Simultaneous measurement of two enzyme activities using infrared spectroscopy: A comparative evaluation of PARAFAC, TUCKER and N-PLS modeling

    DEFF Research Database (Denmark)

    Baum, Andreas; Hansen, Per Waaben; Meyer, Anne S.;

    2013-01-01

    Enzymes are used in many processes to release fermentable sugars for green production of biofuel, or the refinery of biomass for extraction of functional food ingredients such as pectin or prebiotic oligosaccharides. The complex biomasses may, however, require a multitude of specific enzymes which...... are active on specific substrates generating a multitude of products. In this paper we use the plant polymer, pectin, to present a method to quantify enzyme activity of two pectolytic enzymes by monitoring their superimposed spectral evolutions simultaneously. The data is analyzed by three chemometric...... multiway methods, namely PARAFAC, TUCKER3 and N-PLS, to establish simultaneous enzyme activity assays for pectin lyase and pectin methyl esterase. Correlation coefficients Rpred2 for prediction test sets are 0.48, 0.96 and 0.96 for pectin lyase and 0.70, 0.89 and 0.89 for pectin methyl esterase...

  1. Comparative Study of Metaheuristics for the Curve-Fitting Problem: Modeling Neurotransmitter Diffusion and Synaptic Receptor Activation

    Directory of Open Access Journals (Sweden)

    Jesús Montes

    2015-01-01

    data, though a deeper analysis from a biological perspective reveals that some are better suited for this purpose, as they represent more accurately the biological process. Based on the results of this analysis, we propose a set of mathematical equations and a methodology, adequate for modeling several aspects of biochemical synaptic behavior.

  2. Mindfulness training alters emotional memory recall compared to active controls: support for an emotional information processing model of mindfulness

    OpenAIRE

    Doug eRoberts-Wolfe; Matthew eSacchet; Elizabeth eHastings; Harold eRoth; Willoughby eBritton

    2012-01-01

    Objectives: While mindfulness-based interventions have received widespread application in both clinical and non-clinical populations, the mechanism by which mindfulness meditation improves well-being remains elusive. One possibility is that mindfulness training alters the processing of emotional information, similar to prevailing cognitive models of depression and anxiety. The aim of this study was to investigating the effects of mindfulness training on emotional information processing (i.e. ...

  3. Mindfulness Training Alters Emotional Memory Recall Compared to Active Controls: Support for an Emotional Information Processing Model of Mindfulness

    OpenAIRE

    Roberts-Wolfe, Douglas; Sacchet, Matthew D.; Hastings, Elizabeth; Roth, Harold; Britton, Willoughby

    2012-01-01

    Objectives: While mindfulness-based interventions have received widespread application in both clinical and non-clinical populations, the mechanism by which mindfulness meditation improves well-being remains elusive. One possibility is that mindfulness training alters the processing of emotional information, similar to prevailing cognitive models of depression and anxiety. The aim of this study was to investigate the effects of mindfulness training on emotional information processing (i.e., m...

  4. A comparative study of anti-inflammatory activity of lovastatin, simvastatin, atorvastatin and rosuvastatin on acute and chronic inflammation in animal models

    Institute of Scientific and Technical Information of China (English)

    Santoshkumar R Jeevangi; S Manjunath; Sachidananda G Shetti; Chetan Manjunath; Prashant Dass

    2012-01-01

    Objective: To study the anti-inflammatory activity of Lovastatin, Simvastatin, Atorvastatin, and Rosuvastatin on acute and chronic models of inflammation, to compare with the effect of Diclofenac sodium and amongst themselves in rats. Methods: Carrageenin induce rat paw edema method in which 5 animals of each group (6 groups) received orally 4% gum acacia, Diclofenac and 4 statins respectively 1 h before Carrageenin injection in paw. The paw edema volume measured with plethysmograph after 3 h and percentage inhibition of edema in various groups calculated. Rexin pellet granuloma method in which 4 rexin pellets were implanted into dorsum of skin of each rat of 6 groups (n=5) including control, Diclofenac and 4 statin groups respectively. Rats were orally fed with drugs daily for 7 days and on 8th day rexin pellets were removed after sacrificing the rat and dried in incubator 60oC overnight. Pellets were then weighed and percentage inhibition of granulation tissue was calculated and sent for histopathological examination.Results:All the 4 statins showed significant anti-inflammatory activity in the present study in both acute as well as chronic models of inflammation. The anti-inflammatory activity of the 4 statins was significant on comparison with Diclofenac. Lovastatin and Simvastatin demonstrated 10-20% more anti-inflammatory activity than Atorvastatin and Rosuvastatin. Conclusions: The present study revealed the anti-inflammatory effect of statins and thus suggests that the statins have a potential anti-atherosclerotic activity along with its lipid lowering property.

  5. Preclinical activity of the type II CD20 antibody GA101 (obinutuzumab) compared with rituximab and ofatumumab in vitro and in xenograft models.

    Science.gov (United States)

    Herter, Sylvia; Herting, Frank; Mundigl, Olaf; Waldhauer, Inja; Weinzierl, Tina; Fauti, Tanja; Muth, Gunter; Ziegler-Landesberger, Doris; Van Puijenbroek, Erwin; Lang, Sabine; Duong, Minh Ngoc; Reslan, Lina; Gerdes, Christian A; Friess, Thomas; Baer, Ute; Burtscher, Helmut; Weidner, Michael; Dumontet, Charles; Umana, Pablo; Niederfellner, Gerhard; Bacac, Marina; Klein, Christian

    2013-10-01

    We report the first preclinical in vitro and in vivo comparison of GA101 (obinutuzumab), a novel glycoengineered type II CD20 monoclonal antibody, with rituximab and ofatumumab, the two currently approved type I CD20 antibodies. The three antibodies were compared in assays measuring direct cell death (AnnexinV/PI staining and time-lapse microscopy), complement-dependent cytotoxicity (CDC), antibody-dependent cell-mediated cytotoxicity (ADCC), antibody-dependent cell-mediated phagocytosis (ADCP), and internalization. The models used for the comparison of their activity in vivo were SU-DHL4 and RL xenografts. GA101 was found to be superior to rituximab and ofatumumab in the induction of direct cell death (independent of mechanical manipulation required for cell aggregate disruption formed by antibody treatment), whereas it was 10 to 1,000 times less potent in mediating CDC. GA101 showed superior activity to rituximab and ofatumumab in ADCC and whole-blood B-cell depletion assays, and was comparable with these two in ADCP. GA101 also showed slower internalization rate upon binding to CD20 than rituximab and ofatumumab. In vivo, GA101 induced a strong antitumor effect, including complete tumor remission in the SU-DHL4 model and overall superior efficacy compared with both rituximab and ofatumumab. When rituximab-pretreated animals were used, second-line treatment with GA101 was still able to control tumor progression, whereas tumors escaped rituximab treatment. Taken together, the preclinical data show that the glyoengineered type II CD20 antibody GA101 is differentiated from the two approved type I CD20 antibodies rituximab and ofatumumab by its overall preclinical activity, further supporting its clinical investigation.

  6. Comparative study of the neuroprotective and nootropic activities of the carboxylate and amide forms of the HLDF-6 peptide in animal models of Alzheimer's disease.

    Science.gov (United States)

    Bogachouk, Anna P; Storozheva, Zinaida I; Solovjeva, Olga A; Sherstnev, Vyacheslav V; Zolotarev, Yury A; Azev, Vyacheslav N; Rodionov, Igor L; Surina, Elena A; Lipkin, Valery M

    2016-01-01

    A comparative study of the neuroprotective and nootropic activities of two pharmaceutical substances, the HLDF-6 peptide (HLDF-6-OH) and its amide form (HLDF-6-NH2), was conducted. The study was performed in male rats using two models of a neurodegenerative disorder. Cognitive deficit in rats was induced by injection of the beta-amyloid fragment 25-35 (βA 25-35) into the giant-cell nucleus basalis of Meynert or by coinjection of βA 25-35 and ibotenic acid into the hippocampus. To evaluate cognitive functions in animals, three tests were used: the novel object recognition test, the conditioned passive avoidance task and the Morris maze. Comparative analysis of the data demonstrated that the neuroprotective activity of HLDF-6-NH2, evaluated by improvement of cognitive functions in animals, surpassed that of the native HLDF-6-OH peptide. The greater cognitive/ behavioral effects can be attributed to improved kinetic properties of the amide form of the peptide, such as the character of biodegradation and the half-life time. The effects of HLDF-6-NH2 are comparable to, or exceed, those of the reference compounds. Importantly, HLDF-6-NH2 exerts its effects at much lower doses than the reference compounds.

  7. Comparative adaptations in oxidative and glycolytic muscle fibers in a low voluntary wheel running rat model performing three levels of physical activity.

    Science.gov (United States)

    Hyatt, Hayden W; Toedebusch, Ryan G; Ruegsegger, Greg; Mobley, C Brooks; Fox, Carlton D; McGinnis, Graham R; Quindry, John C; Booth, Frank W; Roberts, Michael D; Kavazis, Andreas N

    2015-11-01

    A unique polygenic model of rat physical activity has been recently developed where rats were selected for the trait of low voluntary wheel running. We utilized this model to identify differences in soleus and plantaris muscles of sedentary low voluntary wheel running rats and physically active low voluntary wheel running rats exposed to moderate amounts of treadmill training. Three groups of 28-day-old male Wistar rats were used: (1) rats without a running wheel (SEDENTARY, n = 7), (2) rats housed with a running wheel (WHEEL, n = 7), and (3) rats housed with a running wheel and exercised on the treadmill (5 days/week for 20 min/day at 15.0 m/min) (WHEEL + TREADMILL, n = 7). Animals were euthanized 5 weeks after the start of the experiment and the soleus and plantaris muscles were excised and used for analyses. Increases in skeletal muscle gene expression of peroxisome proliferator-activated receptor gamma coactivator 1 alpha and fibronectin type III domain-containing protein 5 in WHEEL + TREADMILL group were observed. Also, WHEEL + TREADMILL had higher protein levels of superoxide dismutase 2 and decreased levels of oxidative damage. Our data demonstrate that the addition of treadmill training induces beneficial muscular adaptations compared to animals with wheel access alone. Furthermore, our data expand our understanding of differential muscular adaptations in response to exercise in mitochondrial, antioxidant, and metabolic markers.

  8. Comparative activity of pradofloxacin and marbofloxacin against coagulase-positive staphylococci in a pharmacokinetic-pharmacodynamic model based on canine pharmacokinetics.

    Science.gov (United States)

    Körber-Irrgang, B; Wetzstein, H-G; Bagel-Trah, S; Hafner, D; Kresken, M

    2012-12-01

    Pradofloxacin (PRA), a novel veterinary 8-cyano-fluoroquinolone (FQ), is active against Staphylococcus pseudintermedius, the primary cause of canine pyoderma. An in vitro pharmacokinetic-pharmacodynamic model was used to compare the activities of PRA and marbofloxacin (MAR) against three clinical isolates of S. pseudintermedius and reference strain Staphylococcus aureus ATCC 6538. Experiments were performed involving populations of 10(10) CFU corresponding to an inoculum density of approximately 5 × 10(7) CFU/mL. The time course of free drug concentrations in canine serum was modelled, resulting from once daily standard oral dosing of 3 mg of PRA/kg and 2 mg of MAR/kg. In addition, experimentally high doses of 6 mg of PRA/kg and 16 mg of MAR/kg were tested against the least susceptible strain. Viable counts were monitored over 24 h. At concentrations associated with standard doses, PRA caused a faster and more sustained killing than MAR of all strains. The ratios of free drug under the concentration-time curve for 24 h over MIC and the maximum concentration of free drug over MIC were at least 90 and 26, and 8.5 and 2.1 for PRA and MAR, respectively. At experimentally high doses, PRA was superior to MAR in terms of immediate killing. Subpopulations with reduced susceptibility to either FQ did not emerge. We conclude that PRA is likely to be an efficacious therapy of canine staphylococcal infections.

  9. Comparative transcriptome analysis of isogenic cell line models and primary cancers links capicua (CIC) loss to activation of the MAPK signalling cascade.

    Science.gov (United States)

    LeBlanc, Veronique G; Firme, Marlo; Song, Jungeun; Chan, Susanna Y; Lee, Min Hye; Yip, Stephen; Chittaranjan, Suganthi; Marra, Marco A

    2017-06-01

    CIC encodes a transcriptional repressor, capicua (CIC), whose disrupted activity appears to be involved in several cancer types, including type I low-grade gliomas (LGGs) and stomach adenocarcinomas (STADs). To explore human CIC's transcriptional network in an isogenic background, we developed novel isogenic CIC knockout cell lines as model systems, and used these in transcriptome analyses to study the consequences of CIC loss. We also compared our results with analyses of transcriptome data from TCGA for type I LGGs and STADs. We identified 39 candidate targets of CIC transcriptional regulation, and confirmed seven of these as direct targets. We showed that, although many CIC targets appear to be context-specific, the effects of CIC loss converge on the dysregulation of similar biological processes in different cancer types. For example, we found that CIC deficiency was associated with disruptions in the expression of genes involved in cell-cell adhesion, and in the development of several cell and tissue types. We also showed that loss of CIC leads to overexpression of downstream members of the mitogen-activated protein kinase (MAPK) signalling cascade, indicating that CIC deficiency may present a novel mechanism for activation of this oncogenic pathway. © 2017 The Authors. Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland. © 2017 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.

  10. A comparative study of the antitussive activity of levodropropizine and dropropizine in the citric acid-induced cough model in normal subjects.

    Science.gov (United States)

    Fumagalli, G; Cordaro, C I; Vanasia, M; Balzarotti, C; Camusso, L; Caiazzo, G; Maghini, L; Mazzocchi, M; Zennaro, M

    1992-01-01

    Levodropropizine is the levo-rotatory (S)-enantiomer of dropropizine, a racemic non-opiate antitussive agent which has been used clinically for many years. Compared with the racemic drug, levodropropizine exhibits in animal models similar antitussive activity but considerably lower central nervous system (CNS) depressant effects. It is also less likely to cause sedation in treated patients. Since the comparative antitussive potency of the two drugs in clinical experimental models has not been evaluated, the authors performed a randomized, double blind, cross over investigation in which the effects of single oral doses (60 and 90 mg) of levodropropizine and dropropizine were assessed by using the citric acid-induced cough model in eight normal volunteers. Stimulation tests involved inhalation of individual cumulative doses of citric acid (6.3 to 53.3 mg) which at pre-study assessment had been found to induce reproducibly at least ten coughs over a 30 sec period. Each subject was studied by repeating the citric acid stimulation test four times (0 h, 1 h, 2 h and 6 h) on each of five different days separated by intervals of at least three days. In the absence of drug administration (control session), cough response to citric inhalation was remarkably reproducible throughout the 6 h period of observation. A marked and statistically significant reduction in cough response (to about one third--one sixth of the pre-drug values) was observed 1 h after intake for both compounds. At subsequent testing 2 h and 6 h after dosing, cough response was still depressed and did not differ significantly from that observed at 1 h.(ABSTRACT TRUNCATED AT 250 WORDS)

  11. Comparative response of platelet fV and plasma fV to activated protein C and relevance to a model of acute traumatic coagulopathy.

    Directory of Open Access Journals (Sweden)

    James E Campbell

    Full Text Available BACKGROUND: Acute traumatic coagulopathy (ATC has been linked to an increase in activated protein C (aPC from 40 pM in healthy individuals to 175 pM. aPC exerts its activity primarily through cleavage of active coagulation factor Va (fVa. Platelets reportedly possess fVa which is more resistant to aPC cleavage than plasma fVa; this work examines the hypothesis that normal platelets are sufficient to maintain coagulation in the presence of elevated aPC. METHODS: Coagulation responses of normal plasma, fV deficient plasma (fVdp, and isolated normal platelets in fVdp were conducted: prothrombin (PT tests, turbidimetry, and thromboelastography (TEG, including the dose response of aPC on the samples. RESULTS: PT and turbidimetric assays demonstrate that normal plasma is resistant to aPC at doses much higher than those found in ATC. Additionally, an average physiological number of washed normal platelets (200,000 platelets/mm3 was sufficient to eliminate the anti-coagulant effects of aPC up to 10 nM, nearly two orders of magnitude above the ATC concentration and even the steady-state pharmacological concentration of human recombinant aPC, as measured by TEG. aPC also demonstrated no significant effect on clot lysis in normal plasma samples with or without platelets. CONCLUSIONS: Although platelet fVa shows slightly superior resistance to aPC's effects compared to plasma fVa in static models, neither fVa is sufficiently cleaved in simulations of ATC or pharmacologically-delivered aPC to diminish coagulation parameters. aPC is likely a correlative indicator of ATC or may play a cooperative role with other activity altering products generated in ATC.

  12. Comparative study of the enological potential of different winemaking byproducts: implications in the antioxidant activity and color expression of red wine anthocyanins in a model solution.

    Science.gov (United States)

    Jara-Palacios, M José; Gordillo, Belén; González-Miret, M Lourdes; Hernanz, Dolores; Escudero-Gilete, M Luisa; Heredia, Francisco J

    2014-07-23

    Different white winemaking byproducts (pomace, skins, seeds, and stems) were compared as natural sources of phenolic compounds having biological and sensory properties of enological interest. Antioxidant and copigmentation effects of these byproducts were studied in a wine-like model solution. RRLC-DAD was used to establish differences in the phenolic composition, and the ABTS method was used to compare the antioxidant activities. Spectrophotometric and colorimetric analyses were performed to assess the magnitude of copigmentation and the changes induced in the color expression of red wine anthocyanins. Antioxidant and copigmentation properties significantly varied depending on the type of byproduct, which was related to their qualitative and quantitative phenolic composition. Seeds and pomace showed the highest antioxidant potential, whereas skins and pomace led to the strongest and visually perceptible color effects on red wine anthocyanins by multiple copigmentation (darker, more saturated, and vivid bluish colors). Results open the possibility of technological applications for the wine industry based on reusing winemaking byproducts to improve the biological value and color characteristics of red wines.

  13. A Comparative Assessment of Observational Medical Outcomes Partnership and Mini-Sentinel Common Data Models and Analytics: Implications for Active Drug Safety Surveillance.

    Science.gov (United States)

    Xu, Yihua; Zhou, Xiaofeng; Suehs, Brandon T; Hartzema, Abraham G; Kahn, Michael G; Moride, Yola; Sauer, Brian C; Liu, Qing; Moll, Keran; Pasquale, Margaret K; Nair, Vinit P; Bate, Andrew

    2015-08-01

    An often key component to coordinating surveillance activities across distributed networks is the design and implementation of a common data model (CDM). The purpose of this study was to evaluate two drug safety surveillance CDMs from an ecosystem perspective to better understand how differences in CDMs and analytic tools affect usability and interpretation of results. Humana claims data from 2007 to 2012 were mapped to Observational Medical Outcomes Partnership (OMOP) and Mini-Sentinel CDMs. Data were described and compared at the patient level by source code and mapped concepts. Study cohort construction and effect estimates were also compared using two different analytical methods--one based on a new user design implementing a high-dimensional propensity score (HDPS) algorithm and the other based on univariate self-controlled case series (SCCS) design--across six established positive drug-outcome pairs to learn how differences in CDMs and analytics influence steps in the database analytic process and results. Claims data for approximately 7.7 million Humana health plan members were transformed into the two CDMs. Three health outcome cohorts and two drug cohorts showed differences in cohort size and constituency between Mini-Sentinel and OMOP CDMs, which was a result of multiple factors. Overall, the implementation of the HDPS procedure on Mini-Sentinel CDM detected more known positive associations than that on OMOP CDM. The SCCS method results were comparable on both CDMs. Differences in the implementation of the HDPS procedure between the two CDMs were identified; analytic model and risk period specification had a significant impact on the performance of the HDPS procedure on OMOP CDM. Differences were observed between OMOP and Mini-Sentinel CDMs. The analysis of both CDMs at the data model level indicated that such conceptual differences had only a slight but not significant impact on identifying known safety associations. Our results show that differences at

  14. Activity of second-generation ALK inhibitors against crizotinib-resistant mutants in an NPM-ALK model compared to EML4-ALK.

    Science.gov (United States)

    Fontana, Diletta; Ceccon, Monica; Gambacorti-Passerini, Carlo; Mologni, Luca

    2015-07-01

    Anaplastic lymphoma kinase (ALK) is a tyrosine kinase receptor involved in both solid and hematological tumors. About 80% of ALK-positive anaplastic large-cell lymphoma (ALCL) cases are characterized by the t(2;5)(p23;q35) translocation, encoding for the aberrant fusion protein nucleophosmin (NPM)-ALK, whereas 5% of non-small-cell lung cancer (NSCLC) patients carry the inv(2)(p21;p23) rearrangement, encoding for the echinoderm microtubule-associated protein-like 4 (EML4)-ALK fusion. The ALK/c-MET/ROS inhibitor crizotinib successfully improved the treatment of ALK-driven diseases. However, several cases of resistance appeared in NSCLC patients, and ALK amino acid substitutions were identified as a leading cause of resistance to crizotinib. Second-generation ALK inhibitors have been developed in order to overcome crizotinib resistance. In this work, we profiled in vitro the activity of crizotinib, AP26113, ASP3026, alectinib, and ceritinib against six mutated forms of ALK associated with clinical resistance to crizotinib (C1156Y, L1196M, L1152R, G1202R, G1269A, and S1206Y) and provide a classification of mutants according to their level of sensitivity/resistance to the drugs. Since the biological activity of ALK mutations extends beyond the specific type of fusion, both NPM-ALK- and EML4-ALK-positive cellular models were used. Our data revealed that most mutants may be targeted by using different inhibitors. One relevant exception is represented by the G1202R substitution, which was highly resistant to all drugs (>10-fold increased IC50 compared to wild type) and may represent the most challenging mutation to overcome. These results provide a prediction of cross-resistance of known crizotinib-resistant mutations against all second-generation tyrosine kinase inhibitors (TKIs) clinically available, and therefore could be a useful tool to help clinicians in the management of crizotinib-resistance cases.

  15. Comparing the Discrete and Continuous Logistic Models

    Science.gov (United States)

    Gordon, Sheldon P.

    2008-01-01

    The solutions of the discrete logistic growth model based on a difference equation and the continuous logistic growth model based on a differential equation are compared and contrasted. The investigation is conducted using a dynamic interactive spreadsheet. (Contains 5 figures.)

  16. Comparing the Discrete and Continuous Logistic Models

    Science.gov (United States)

    Gordon, Sheldon P.

    2008-01-01

    The solutions of the discrete logistic growth model based on a difference equation and the continuous logistic growth model based on a differential equation are compared and contrasted. The investigation is conducted using a dynamic interactive spreadsheet. (Contains 5 figures.)

  17. Comparative dynamics in a health investment model.

    Science.gov (United States)

    Eisenring, C

    1999-10-01

    The method of comparative dynamics fully exploits the inter-temporal structure of optimal control models. I derive comparative dynamic results in a simplified demand for health model. The effect of a change in the depreciation rate on the optimal paths for health capital and investment in health is studied by use of a phase diagram.

  18. Loss Given Default Modelling: Comparative Analysis

    OpenAIRE

    Yashkir, Olga; Yashkir, Yuriy

    2013-01-01

    In this study we investigated several most popular Loss Given Default (LGD) models (LSM, Tobit, Three-Tiered Tobit, Beta Regression, Inflated Beta Regression, Censored Gamma Regression) in order to compare their performance. We show that for a given input data set, the quality of the model calibration depends mainly on the proper choice (and availability) of explanatory variables (model factors), but not on the fitting model. Model factors were chosen based on the amplitude of their correlati...

  19. Migration of antimony from PET bottles into beverages: determination of the activation energy of diffusion and migration modelling compared with literature data.

    Science.gov (United States)

    Welle, F; Franz, R

    2011-01-01

    Plastics bottles made from polyethylene terephthalate (PET) are increasingly used for soft drinks, mineral water, juices and beer. In this study a literature review is presented concerning antimony levels found both in PET materials as well as in foods and food simulants. On the other hand, 67 PET samples from the European bottle market were investigated for their residual antimony concentrations. A mean value of 224 ± 32 mg kg(-1) was found, the median was 220 mg kg(-1). Diffusion coefficients for antimony in PET bottle materials were experimentally determined at different temperature between 105 and 150°C. From these data, the activation energy of diffusion for antimony species from the PET bottle wall into beverages and food simulants was calculated. The obtained value of 189 kJ mol(-1) was found to be in good agreement with published data on PET microwave trays (184 kJ mol(-1)). Based on these results, the migration of antimony into beverages was predicted by mathematical migration modelling for different surface/volume ratios and antimony bottle wall concentrations. The results were compared with literature data as well as international legal limits and guidelines values for drinking water and the migration limit set from food packaging legislation. It was concluded that antimony levels in beverages due to migration from PET bottles manufactured according to the state of the art can never reach or exceed the European-specific migration limit of 40 microg kg(-1). Maximum migration levels caused by room-temperature storage even after 3 years will never be essentially higher than 2.5 microg kg(-1) and in any case will be below the European limit of 5 microg kg(-1) for drinking water. The results of this study confirm that the exposure of the consumer by antimony migration from PET bottles into beverages and even into edible oils reaches approximately 1% of the current tolerable daily intake (TDI) established by World Health Organisation (WHO). Having

  20. A Comparative of business process modelling techniques

    Science.gov (United States)

    Tangkawarow, I. R. H. T.; Waworuntu, J.

    2016-04-01

    In this era, there is a lot of business process modeling techniques. This article is the research about differences of business process modeling techniques. For each technique will explain about the definition and the structure. This paper presents a comparative analysis of some popular business process modelling techniques. The comparative framework is based on 2 criteria: notation and how it works when implemented in Somerleyton Animal Park. Each technique will end with the advantages and disadvantages. The final conclusion will give recommend of business process modeling techniques that easy to use and serve the basis for evaluating further modelling techniques.

  1. Comparing linear probability model coefficients across groups

    DEFF Research Database (Denmark)

    Holm, Anders; Ejrnæs, Mette; Karlson, Kristian Bernt

    2015-01-01

    This article offers a formal identification analysis of the problem in comparing coefficients from linear probability models between groups. We show that differences in coefficients from these models can result not only from genuine differences in effects, but also from differences in one or more...... these limitations, and we suggest a restricted approach to using linear probability model coefficients in group comparisons....

  2. Major models used in comparative management

    OpenAIRE

    Ioan Constantin Dima; Codruta Dura

    2001-01-01

    Comparative management literature emphasizes the following models: Farmer-Richman Model (based on the assumption that environment represents the main factor whom influence upon management is decisive); Rosalie Tung Model (using the following variables:environment,or extra-organisational variables, intra-organisational variables, personal and result variables); Child Model (including the three determinative domains-contingency, culture and economic system-threated as items objectively connecte...

  3. Is it Worth Comparing Different Bankruptcy Models?

    Directory of Open Access Journals (Sweden)

    Miroslava Dolejšová

    2015-01-01

    Full Text Available The aim of this paper is to compare the performance of small enterprises in the Zlín and Olomouc Regions. These enterprises were assessed using the Altman Z-Score model, the IN05 model, the Zmijewski model and the Springate model. The batch selected for this analysis included 16 enterprises from the Zlín Region and 16 enterprises from the Olomouc Region. Financial statements subjected to the analysis are from 2006 and 2010. The statistical data analysis was performed using the one-sample z-test for proportions and the paired t-test. The outcomes of the evaluation run using the Altman Z-Score model, the IN05 model and the Springate model revealed the enterprises to be financially sound, but the Zmijewski model identified them as being insolvent. The one-sample z-test for proportions confirmed that at least 80% of these enterprises show a sound financial condition. A comparison of all models has emphasized the substantial difference produced by the Zmijewski model. The paired t-test showed that the financial performance of small enterprises had remained the same during the years involved. It is recommended that small enterprises assess their financial performance using two different bankruptcy models. They may wish to combine the Zmijewski model with any bankruptcy model (the Altman Z-Score model, the IN05 model or the Springate model to ensure a proper method of analysis.

  4. Comparing repetition-based melody segmentation models

    NARCIS (Netherlands)

    Rodríguez López, M.E.; de Haas, Bas; Volk, Anja

    2014-01-01

    This paper reports on a comparative study of computational melody segmentation models based on repetition detection. For the comparison we implemented five repetition-based segmentation models, and subsequently evaluated their capacity to automatically find melodic phrase boundaries in a corpus of 2

  5. Comparing models of Red Knot population dynamics

    Science.gov (United States)

    McGowan, Conor

    2015-01-01

    Predictive population modeling contributes to our basic scientific understanding of population dynamics, but can also inform management decisions by evaluating alternative actions in virtual environments. Quantitative models mathematically reflect scientific hypotheses about how a system functions. In Delaware Bay, mid-Atlantic Coast, USA, to more effectively manage horseshoe crab (Limulus polyphemus) harvests and protect Red Knot (Calidris canutus rufa) populations, models are used to compare harvest actions and predict the impacts on crab and knot populations. Management has been chiefly driven by the core hypothesis that horseshoe crab egg abundance governs the survival and reproduction of migrating Red Knots that stopover in the Bay during spring migration. However, recently, hypotheses proposing that knot dynamics are governed by cyclical lemming dynamics garnered some support in data analyses. In this paper, I present alternative models of Red Knot population dynamics to reflect alternative hypotheses. Using 2 models with different lemming population cycle lengths and 2 models with different horseshoe crab effects, I project the knot population into the future under environmental stochasticity and parametric uncertainty with each model. I then compare each model's predictions to 10 yr of population monitoring from Delaware Bay. Using Bayes' theorem and model weight updating, models can accrue weight or support for one or another hypothesis of population dynamics. With 4 models of Red Knot population dynamics and only 10 yr of data, no hypothesis clearly predicted population count data better than another. The collapsed lemming cycle model performed best, accruing ~35% of the model weight, followed closely by the horseshoe crab egg abundance model, which accrued ~30% of the weight. The models that predicted no decline or stable populations (i.e. the 4-yr lemming cycle model and the weak horseshoe crab effect model) were the most weakly supported.

  6. Adapted Active Appearance Models

    Directory of Open Access Journals (Sweden)

    Renaud Séguier

    2009-01-01

    Full Text Available Active Appearance Models (AAMs are able to align efficiently known faces under duress, when face pose and illumination are controlled. We propose Adapted Active Appearance Models to align unknown faces in unknown poses and illuminations. Our proposal is based on the one hand on a specific transformation of the active model texture in an oriented map, which changes the AAM normalization process; on the other hand on the research made in a set of different precomputed models related to the most adapted AAM for an unknown face. Tests on public and private databases show the interest of our approach. It becomes possible to align unknown faces in real-time situations, in which light and pose are not controlled.

  7. Genetic network models: a comparative study

    Science.gov (United States)

    van Someren, Eugene P.; Wessels, Lodewyk F. A.; Reinders, Marcel J. T.

    2001-06-01

    Currently, the need arises for tools capable of unraveling the functionality of genes based on the analysis of microarray measurements. Modeling genetic interactions by means of genetic network models provides a methodology to infer functional relationships between genes. Although a wide variety of different models have been introduced so far, it remains, in general, unclear what the strengths and weaknesses of each of these approaches are and where these models overlap and differ. This paper compares different genetic modeling approaches that attempt to extract the gene regulation matrix from expression data. A taxonomy of continuous genetic network models is proposed and the following important characteristics are suggested and employed to compare the models: inferential power; predictive power; robustness; consistency; stability and computational cost. Where possible, synthetic time series data are employed to investigate some of these properties. The comparison shows that although genetic network modeling might provide valuable information regarding genetic interactions, current models show disappointing results on simple artificial problems. For now, the simplest models are favored because they generalize better, but more complex models will probably prevail once their bias is more thoroughly understood and their variance is better controlled.

  8. Comparing linear probability model coefficients across groups

    DEFF Research Database (Denmark)

    Holm, Anders; Ejrnæs, Mette; Karlson, Kristian Bernt

    2015-01-01

    This article offers a formal identification analysis of the problem in comparing coefficients from linear probability models between groups. We show that differences in coefficients from these models can result not only from genuine differences in effects, but also from differences in one or more...... of the following three components: outcome truncation, scale parameters and distributional shape of the predictor variable. These results point to limitations in using linear probability model coefficients for group comparisons. We also provide Monte Carlo simulations and real examples to illustrate...... these limitations, and we suggest a restricted approach to using linear probability model coefficients in group comparisons....

  9. A Comparative Oncology Study of Iniparib Defines Its Pharmacokinetic Profile and Biological Activity in a Naturally-Occurring Canine Cancer Model.

    Directory of Open Access Journals (Sweden)

    Corey Saba

    Full Text Available Development of iniparib as an anti-cancer agent was hindered in part by lingering questions regarding its mechanism of action, the activity of its metabolites, and their potential accumulation in tumors. Due to strong similarities in metabolism of iniparib between humans and dogs, a veterinary clinical trial in pet dogs with spontaneous cancers was designed to answer specific questions pertaining to pharmacokinetic exposures and tolerability of iniparib. Dogs were treated with iniparib alone and in combination with carboplatin chemotherapy. Iniparib doses ranged between 10-70 mg/kg intravenously (IV. Plasma, tumor and normal tissue samples were collected before and at various time points scheduled after exposure for pharmacokinetic and biologic analysis. The primary endpoints included characterization of dose-limiting toxicities (DLT and determination of the drug exposures that could be achieved in both normal and tumor tissues. Nineteen dogs were treated. DLT included fever, anorexia, diarrhea, neutropenia, and thrombocytopenia; most effects were attributable to carboplatin based on the timing of adverse event onset. The maximum tolerated dose (MTD of iniparib was not identified. Moderate to high variability in plasma exposure was noted for iniparib and all metabolites between animals. When quantifiable, iniparib and metabolite plasma:tumor ratios were < 0.088 and <1.7, respectively. In this study, iniparib was well tolerated as a single agent and in combination with carboplatin over a range of doses. However, clinically relevant concentrations of the parent drug and selected metabolites were not detectable in canine tumor tissues at any studied dose, thus eliminating expectations for clinical responses in dogs or humans. Negative clinical trials in humans, and the uncertainties of its mechanism of action, ultimately led to the decision to stop clinical development of the drug. Nevertheless, the questions that can be asked and answered within

  10. Comparing and Using Occupation-Focused Models.

    Science.gov (United States)

    Wong, Su Ren; Fisher, Gail

    2015-01-01

    As health care moves toward understanding the importance of function, participation and occupation, occupational therapists would be well served to use occupation-focused theories to guide intervention. Most therapists understand that applying occupation-focused models supports best practice, but many do not routinely use these models. Barriers to application of theory include lack of understanding of the models and limited strategies to select and apply them for maximum client benefit. The aim of this article is to compare occupation-focused models and provide recommendations on how to choose and combine these models in practice; and to provide a systematic approach for integrating occupation-focused models with frames of reference to guide assessment and intervention.

  11. Comparing coefficients of nested nonlinear probability models

    DEFF Research Database (Denmark)

    Kohler, Ulrich; Karlson, Kristian Bernt; Holm, Anders

    2011-01-01

    In a series of recent articles, Karlson, Holm and Breen have developed a method for comparing the estimated coeffcients of two nested nonlinear probability models. This article describes this method and the user-written program khb that implements the method. The KHB-method is a general decomposi......In a series of recent articles, Karlson, Holm and Breen have developed a method for comparing the estimated coeffcients of two nested nonlinear probability models. This article describes this method and the user-written program khb that implements the method. The KHB-method is a general...... decomposition method that is unaffected by the rescaling or attenuation bias that arise in cross-model comparisons in nonlinear models. It recovers the degree to which a control variable, Z, mediates or explains the relationship between X and a latent outcome variable, Y*, underlying the nonlinear probability...

  12. Comparative activities of selected fluoroquinolones against dynamic populations of Actinobacillus pleuropneumoniae in an in vitro model of time-kill continuous culture experiment.

    Science.gov (United States)

    Damte, Dereje; Lee, Seung-Jin; Yohannes, Sileshi B; Hossain, Md Akil; Suh, Joo-Won; Park, Seung-Chun

    2013-12-01

    The aim of the current study was to demonstrate and compare the impact of different pharmacokinetics of marbofloxacin, enrofloxacin and difloxacin on their antimicrobial effects, their killing and re-growth kinetics, and the population dynamics of Actinobacillus pleuropneumoniae clinical isolates in an in vitro dynamic model. Selected clinical isolates of A. pleuropneumoniae and three fluoroquinolones at a range of simulated AUC(24)/MIC ratios of multiple doses were investigated. At the same simulated AUC(24)/MIC ratios of the three fluoroquinolones, the killing re-growth profile and I(E) values (intensity of the antimicrobial effect) revealed strain- and fluoroquinolone-specific effects. For example, a 31% lower I(E) of difloxacin was observed in AppK5 (biofilm-former) than in AppK2 (biofilm-non-former) at the same AUC(24)/MIC ratio of 120 h. In addition, losses in A. pleuropneumoniae susceptibility of both strains by the three fluoroquinolones were observed. AUC(24)/MPC ratios of 20.89 and 39.81 for marbofloxacin, 17.32 and 19.49 for enrofloxacin and 31.62 and 60.25 for difloxacin were estimated to be protective against the selection of AppK2 and AppK5 strain mutants, respectively. Integration of these in vitro data with published pharmacokinetics revealed the inadequacy of the conventional clinical doses of the three drugs to attain the above protective values for minimum biofilm eradication concentration (MBEC) and concentration to prevent growth of 90% of the mutant subpopulation (MPC(90)). In conclusion, the results suggest optimising doses could suffice for resistant mutants control, while for biofilm-forming strains combination with biofilm-disrupting agents to reduce the MBEC to achieve AUC/MBEC ratios within the possible dosing regimens is desired. Copyright © 2013 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.

  13. Comparing numerically exact and modelled static friction

    Directory of Open Access Journals (Sweden)

    Krengel Dominik

    2017-01-01

    Full Text Available Currently there exists no mechanically consistent “numerically exact” implementation of static and dynamic Coulomb friction for general soft particle simulations with arbitrary contact situations in two or three dimension, but only along one dimension. We outline a differential-algebraic equation approach for a “numerically exact” computation of friction in two dimensions and compare its application to the Cundall-Strack model in some test cases.

  14. Comparative analysis of Goodwin's business cycle models

    Science.gov (United States)

    Antonova, A. O.; Reznik, S.; Todorov, M. D.

    2016-10-01

    We compare the behavior of solutions of Goodwin's business cycle equation in the form of neutral delay differential equation with fixed delay (NDDE model) and in the form of the differential equations of 3rd, 4th and 5th orders (ODE model's). Such ODE model's (Taylor series expansion of NDDE in powers of θ) are proposed in N. Dharmaraj and K. Vela Velupillai [6] for investigation of the short periodic sawthooth oscillations in NDDE. We show that the ODE's of 3rd, 4th and 5th order may approximate the asymptotic behavior of only main Goodwin's mode, but not the sawthooth modes. If the order of the Taylor series expansion exceeds 5, then the approximate ODE becomes unstable independently of time lag θ.

  15. Minimalist models for proteins: a comparative analysis.

    Science.gov (United States)

    Tozzini, Valentina

    2010-08-01

    The last decade has witnessed a renewed interest in the coarse-grained (CG) models for biopolymers, also stimulated by the needs of modern molecular biology, dealing with nano- to micro-sized bio-molecular systems and larger than microsecond timescale. This combination of size and timescale is, in fact, hard to access by atomic-based simulations. Coarse graining the system is a route to be followed to overcome these limits, but the ways of practically implementing it are many and different, making the landscape of CG models very vast and complex. In this paper, the CG models are reviewed and their features, applications and performances compared. This analysis, restricted to proteins, focuses on the minimalist models, namely those reducing at minimum the number of degrees of freedom without losing the possibility of explicitly describing the secondary structures. This class includes models using a single or a few interacting centers (beads) for each amino acid. From this analysis several issues emerge. The difficulty in building these models resides in the need for combining transferability/predictive power with the capability of accurately reproducing the structures. It is shown that these aspects could be optimized by accurately choosing the force field (FF) terms and functional forms, and combining different parameterization procedures. In addition, in spite of the variety of the minimalist models, regularities can be found in the parameters values and in FF terms. These are outlined and schematically presented with the aid of a generic phase diagram of the polypeptide in the parameter space and, hopefully, could serve as guidelines for the development of minimalist models incorporating the maximum possible level of predictive power and structural accuracy.

  16. On Activity modelling in process modeling

    Directory of Open Access Journals (Sweden)

    Dorel Aiordachioaie

    2001-12-01

    Full Text Available The paper is looking to the dynamic feature of the meta-models of the process modelling process, the time. Some principles are considered and discussed as main dimensions of any modelling activity: the compatibility of the substances, the equipresence of phenomena and the solvability of the model. The activity models are considered and represented at meta-level.

  17. Accuracy of stereolithographically printed digital models compared to plaster models.

    Science.gov (United States)

    Camardella, Leonardo Tavares; Vilella, Oswaldo V; van Hezel, Marleen M; Breuning, Karel H

    2017-03-30

    This study compared the accuracy of plaster models from alginate impressions and printed models from intraoral scanning. A total of 28 volunteers were selected and alginate impressions and intraoral scans were used to make plaster models and digital models of their dentition, respectively. The digital models were printed using a stereolithographic (SLA) 3D printer with a horseshoe-shaped design. Two calibrated examiners measured distances on the plaster and printed models with a digital caliper. The paired t test was used to determine intraobserver error and compare the measurements. The Pearson correlation coefficient was used to evaluate the reliability of measurements for each model type. The measurements on plaster models and printed models show some significant differences in tooth dimensions and interarch parameters, but these differences were not clinically relevant, except for the transversal measurements. The upper and lower intermolar distances on the printed models were statistically significant and clinically relevant smaller. Printed digital models with the SLA 3D printer studied, with a horseshoe-shaped base made from intraoral scans cannot replace conventional plaster models from alginate impressions in orthodontics for diagnosis and treatment planning because of their clinically relevant transversal contraction.

  18. Comparing evaluation activities across multiple theories of practice.

    Science.gov (United States)

    Dillman, Lisa M

    2013-06-01

    This article compares and contrasts the evaluation activities described in Practical Participatory Evaluation (Cousins & Whitmore, 1998), Values-engaged Evaluation (Greene, 2005), and Emergent Realist Evaluation (Mark, Henry, & Julnes, 1998). Using the logic models developed to depict each of the three evaluation theories (Hansen, Alkin, & Wallace, 2013) as a starting point, both quantitative and qualitative analysis techniques are employed to discuss the similarities and differences across the practice prescriptions. The approaches are then described according to Miller's (2010) standards for empirical examinations of evaluation theory. Specifically, I offer speculation about their operational specificity and feasibility in practice. I argue that none of the models is completely specific, or wholly unique, and they all present challenges of adaptation into the field. However, the models each offer varying degrees of guidance and unique elements through their prescriptions.

  19. Learning models of activities involving interacting objects

    DEFF Research Database (Denmark)

    Manfredotti, Cristina; Pedersen, Kim Steenstrup; Hamilton, Howard J.;

    2013-01-01

    We propose the LEMAIO multi-layer framework, which makes use of hierarchical abstraction to learn models for activities involving multiple interacting objects from time sequences of data concerning the individual objects. Experiments in the sea navigation domain yielded learned models that were...... then successfully applied to activity recognition, activity simulation and multi-target tracking. Our method compares favourably with respect to previously reported results using Hidden Markov Models and Relational Particle Filtering....

  20. Comparing models of offensive cyber operations

    CSIR Research Space (South Africa)

    Grant, T

    2015-10-01

    Full Text Available was performed, using as a springboard seven models of cyber- attack, and resulted in the development of what is described as a canonical model. Keywords: Offensive cyber operations; Process models; Rational reconstructions; Canonical models; Structured...

  1. Generic active appearance models revisited

    NARCIS (Netherlands)

    Tzimiropoulos, Georgios; Alabort-i-Medina, Joan; Zafeiriou, Stefanos; Pantic, Maja

    2012-01-01

    The proposed Active Orientation Models (AOMs) are gen- erative models of facial shape and appearance. Their main dierences with the well-known paradigm of Active Appearance Models (AAMs) are (i) they use a dierent statistical model of appearance, (ii) they are accompanied by a robust algorithm for m

  2. Modeling of active beam units with Modelica

    DEFF Research Database (Denmark)

    Maccarini, Alessandro; Hultmark, Göran; Vorre, Anders

    2015-01-01

    This paper proposes an active beam model suitable for building energy simulations with the programming language Modelica. The model encapsulates empirical equations derived by a novel active beam terminal unit that operates with low-temperature heating and high-temperature cooling systems....... Measurements from a full-scale experiment are used to compare the thermal behavior of the active beam with the one predicted by simulations. The simulation results show that the model corresponds closely with the actual operation. The model predicts the outlet water temperature of the active beam...... with a maximum mean absolute error of 0.18 °C. In term of maximum mean absolute percentage error, simulation results differ by 0.9%. The methodology presented is general enough to be applied for modeling other active beam units. Modeling of active beam units with Modelica. Available from: https...

  3. Activated sludge model No. 3

    DEFF Research Database (Denmark)

    Gujer, W.; Henze, M.; Mino, T.

    1999-01-01

    The Activated Sludge Model No. 3 (ASM3) can predict oxygen consumption, sludge production, nitrification and denitrification of activated sludge systems. It relates to the Activated Sludge Model No. 1 (ASM1) and corrects for some defects of ASM I. In addition to ASM1, ASM3 includes storage...

  4. Atmosphere of Mars - Mariner IV models compared.

    Science.gov (United States)

    Eshleman, V. R.; Fjeldbo, G.; Fjeldbo, W. C.

    1966-01-01

    Mariner IV models of three Mars atmospheric layers analogous to terrestrial E, F-1 and F-2 layers, considering relative mass densities, temperatures, carbon dioxide photodissociation and ionization profile

  5. Event-Based Activity Modeling

    DEFF Research Database (Denmark)

    Bækgaard, Lars

    2004-01-01

    We present and discuss a modeling approach that supports event-based modeling of information and activity in information systems. Interacting human actors and IT-actors may carry out such activity. We use events to create meaningful relations between information structures and the related activit...

  6. Comparative Distributions of Hazard Modeling Analysis

    Directory of Open Access Journals (Sweden)

    Rana Abdul Wajid

    2006-07-01

    Full Text Available In this paper we present the comparison among the distributions used in hazard analysis. Simulation technique has been used to study the behavior of hazard distribution modules. The fundamentals of Hazard issues are discussed using failure criteria. We present the flexibility of the hazard modeling distribution that approaches to different distributions.

  7. Physical activity changes during pregnancy in a comparative impact trail

    Science.gov (United States)

    Delta Healthy Sprouts was designed to test the comparative impact of two home visiting programs on weight status, dietary intake, physical activity, and other health behaviors of rural, Southern African American women and their infants. Results pertaining to physical activity outcomes in the gestat...

  8. Comparing models of offensive cyber operations

    CSIR Research Space (South Africa)

    Grant, T

    2012-03-01

    Full Text Available (CSIR), Pretoria, South Africa tj.grant@nlda.nl iburke@csir.co.za rvhheerden@csir.co.za Abstract: Cyber operations denote the response of governments and organisations to cyber crime, terrorism, and warfare. To date, cyber operations have been.... This could include responding to an (impending) attack by counter-attacking or by proactively neutralizing the source of an impending attack. A good starting point to improving understanding would be to model the offensive cyber operations process...

  9. Protein comparative sequence analysis and computer modeling.

    Science.gov (United States)

    Hambly, Brett D; Oakley, Cecily E; Fajer, Piotr G

    2008-01-01

    A problem frequently encountered by the biological scientist is the identification of a previously unknown gene or protein sequence, where there are few or no clues as to the biochemical function, ligand specificity, gene regulation, protein-protein interactions, tissue specificity, cellular localization, developmental phase of activity, or biological role. Through the process of bioinformatics there are now many approaches for predicting answers to at least some of these questions, often then allowing the design of more insightful experiments to characterize more definitively the new protein.

  10. Comparative analysis of existing models for power-grid synchronization

    CERN Document Server

    Nishikawa, Takashi

    2015-01-01

    The dynamics of power-grid networks is becoming an increasingly active area of research within the physics and network science communities. The results from such studies are typically insightful and illustrative, but are often based on simplifying assumptions that can be either difficult to assess or not fully justified for realistic applications. Here we perform a comprehensive comparative analysis of three leading models recently used to study synchronization dynamics in power-grid networks -- a fundamental problem of practical significance given that frequency synchronization of all power generators in the same interconnection is a necessary condition for a power grid to operate. We show that each of these models can be derived from first principles within a common framework based on the classical model of a generator, thereby clarifying all assumptions involved. This framework allows us to view power grids as complex networks of coupled second-order phase oscillators with both forcing and damping terms. U...

  11. Active control: Wind turbine model

    DEFF Research Database (Denmark)

    Bindner, H.

    1999-01-01

    This report is a part of the reporting of the work done in the project 'Active Control of Wind Turbines'. This project aim is to develop a simulation model for design of control systems for turbines with pitch control and to use that model to designcontrollers. This report describes the model...... developed for controller design and analysis. Emphasis has been put on establishment of simple models describing the dynamic behavior of the wind turbine in adequate details for controller design. This hasbeen done with extensive use of measurements as the basis for selection of model complexity and model...... validation as well as parameter estimation. The model includes a simple model of the structure of the turbine including tower and flapwise blade bending,a detailed model of the gear box and induction generator, a linearized aerodynamic model including modelling of induction lag and actuator and sensor models...

  12. A comparative examination of the adsorption mechanism of an anionic textile dye (RBY 3GL) onto the powdered activated carbon (PAC) using various the isotherm models and kinetics equations with linear and non-linear methods

    Science.gov (United States)

    Açıkyıldız, Metin; Gürses, Ahmet; Güneş, Kübra; Yalvaç, Duygu

    2015-11-01

    The present study was designed to compare the linear and non-linear methods used to check the compliance of the experimental data corresponding to the isotherm models (Langmuir, Freundlich, and Redlich-Peterson) and kinetics equations (pseudo-first order and pseudo-second order). In this context, adsorption experiments were carried out to remove an anionic dye, Remazol Brillant Yellow 3GL (RBY), from its aqueous solutions using a commercial activated carbon as a sorbent. The effects of contact time, initial RBY concentration, and temperature onto adsorbed amount were investigated. The amount of dye adsorbed increased with increased adsorption time and the adsorption equilibrium was attained after 240 min. The amount of dye adsorbed enhanced with increased temperature, suggesting that the adsorption process is endothermic. The experimental data was analyzed using the Langmuir, Freundlich, and Redlich-Peterson isotherm equations in order to predict adsorption isotherm. It was determined that the isotherm data were fitted to the Langmuir and Redlich-Peterson isotherms. The adsorption process was also found to follow a pseudo second-order kinetic model. According to the kinetic and isotherm data, it was found that the determination coefficients obtained from linear method were higher than those obtained from non-linear method.

  13. Active control: Wind turbine model

    Energy Technology Data Exchange (ETDEWEB)

    Bindner, Henrik

    1999-07-01

    This report is a part of the reporting of the work done in the project `Active Control of Wind Turbines`. This project aim is to develop a simulation model for design of control systems for turbines with pitch control and to use that model to design controllers. This report describes the model developed for controller design and analysis. Emphasis has been put on establishment of simple models describing the dynamic behavior of the wind turbine in adequate details for controller design. This has been done with extensive use of measurements as the basis for selection of model complexity and model validation as well as parameter estimation. The model includes a simple model of the structure of the turbine including tower and flapwise blade bending, a detailed model of the gear box and induction generator, a linearized aerodynamic model including modelling of induction lag and actuator and sensor models. The models are all formulated as linear differential equations. The models are validated through comparisons with measurements performed on a Vestas WD 34 400 kW wind turbine. It is shown from a control point of view simple linear models can be used to describe the dynamic behavior of a pitch controlled wind turbine. The model and the measurements corresponds well in the relevant frequency range. The developed model is therefore applicable for controller design. (au) EFP-91. 18 ills., 22 refs.

  14. Comparative analysis of existing models for power-grid synchronization

    Science.gov (United States)

    Nishikawa, Takashi; Motter, Adilson E.

    2015-01-01

    The dynamics of power-grid networks is becoming an increasingly active area of research within the physics and network science communities. The results from such studies are typically insightful and illustrative, but are often based on simplifying assumptions that can be either difficult to assess or not fully justified for realistic applications. Here we perform a comprehensive comparative analysis of three leading models recently used to study synchronization dynamics in power-grid networks—a fundamental problem of practical significance given that frequency synchronization of all power generators in the same interconnection is a necessary condition for a power grid to operate. We show that each of these models can be derived from first principles within a common framework based on the classical model of a generator, thereby clarifying all assumptions involved. This framework allows us to view power grids as complex networks of coupled second-order phase oscillators with both forcing and damping terms. Using simple illustrative examples, test systems, and real power-grid datasets, we study the inherent frequencies of the oscillators as well as their coupling structure, comparing across the different models. We demonstrate, in particular, that if the network structure is not homogeneous, generators with identical parameters need to be modeled as non-identical oscillators in general. We also discuss an approach to estimate the required (dynamical) system parameters that are unavailable in typical power-grid datasets, their use for computing the constants of each of the three models, and an open-source MATLAB toolbox that we provide for these computations.

  15. Fast Newton active appearance models

    NARCIS (Netherlands)

    Kossaifi, Jean; Tzimiropoulos, Georgios; Pantic, Maja

    2014-01-01

    Active Appearance Models (AAMs) are statistical models of shape and appearance widely used in computer vision to detect landmarks on objects like faces. Fitting an AAM to a new image can be formulated as a non-linear least-squares problem which is typically solved using iterative methods. Owing to i

  16. COMPARATIVE STUDY ON MAIN SOLVENCY ASSESSMENT MODELS FOR INSURANCE FIELD

    Directory of Open Access Journals (Sweden)

    Daniela Nicoleta SAHLIAN

    2015-07-01

    Full Text Available During the recent financial crisis of insurance domain, there were imposed new aspects that have to be taken into account concerning the risks management and surveillance activity. The insurance societies could develop internal models in order to determine the minimum capital requirement imposed by the new regulations that are to be adopted on 1 January 2016. In this respect, the purpose of this research paper is to offer a real presentation and comparing with the main solvency regulation systems used worldwide, the accent being on their common characteristics and current tendencies. Thereby, we would like to offer a better understanding of the similarities and differences between the existent solvency regimes in order to develop the best regime of solvency for Romania within the Solvency II project. The study will show that there are clear differences between the existent Solvency I regime and the new approaches based on risk and will also point out the fact that even the key principles supporting the new solvency regimes are convergent, there are a lot of approaches for the application of these principles. In this context, the question we would try to find the answer is "how could the global solvency models be useful for the financial surveillance authority of Romania for the implementation of general model and for the development of internal solvency models according to the requirements of Solvency II" and "which would be the requirements for the implementation of this type of approach?". This thing makes the analysis of solvency models an interesting exercise.

  17. Comparative Study of MHD Modeling of the Background Solar Wind

    CERN Document Server

    Gressl, C; Temmer, M; Odstrcil, D; Linker, J A; Mikic, Z; Riley, P

    2013-01-01

    Knowledge about the background solar wind plays a crucial role in the framework of space weather forecasting. In-situ measurements of the background solar wind are only available for a few points in the heliosphere where spacecraft are located, therefore we have to rely on heliospheric models to derive the distribution of solar wind parameters in interplanetary space. We test the performance of different solar wind models, namely Magnetohydrodynamic Algorithm outside a Sphere/ENLIL (MAS/ENLIL), Wang-Sheeley-Arge/ENLIL (WSA/ENLIL), and MAS/MAS, by comparing model results with in-situ measurements from spacecraft located at 1 AU distance to the Sun (ACE, Wind). To exclude the influence of interplanetary coronal mass ejections (ICMEs), we chose the year 2007 as a time period with low solar activity for our comparison. We found that the general structure of the background solar wind is well reproduced by all models. The best model results were obtained for the parameter solar wind speed. However, the predicted ar...

  18. Comparative and pharmacophore model for deacetylase SIRT1

    Science.gov (United States)

    Huhtiniemi, Tero; Wittekindt, Carsten; Laitinen, Tuomo; Leppänen, Jukka; Salminen, Antero; Poso, Antti; Lahtela-Kakkonen, Maija

    2006-09-01

    Sirtuins are NAD-dependent histone deacetylases, which cleave the acetyl-group from acetylated proteins, such as histones but also the acetyl groups from several transcription factors, and in this way can change their activities. Of all seven mammalian SirTs, the human sirtuin SirT1 has been the most extensively studied. However, there is no crystal structure or comparative model reported for SirT1. We have therefore built up a three-dimensional comparison model of the SirT1 protein catalytic core (domain area from residues 244 to 498 of the full length SirT1) in order to assist in the investigation of active site-ligand interactions and in the design of novel SirT1 inhibitors. In this study we also propose the binding-mode of recently reported set of indole-based inhibitors in SirT1. The site of interaction and the ligand conformation were predicted by the use of molecular docking techniques. To distinguish between active and inactive compounds, a post-docking filter based on H-bond network was constructed. Docking results were used to investigate the pharmacophore and to identify a filter for database mining.

  19. Comparing Theoretical Perspectives in Describing Mathematics Departments: Complexity and Activity

    Science.gov (United States)

    Beswick, Kim; Watson, Anne; De Geest, Els

    2010-01-01

    We draw on two studies of mathematics departments in 11-18 comprehensive maintained schools in England to compare and contrast the insights provided by differing theoretical perspectives. In one study, activity theory was used to describe common features of the work of three departments. In the other, a mathematics department was viewed and…

  20. Modeling interdisciplinary activities involving Mathematics

    DEFF Research Database (Denmark)

    Iversen, Steffen Møllegaard

    2006-01-01

    In this paper a didactical model is presented. The goal of the model is to work as a didactical tool, or conceptual frame, for developing, carrying through and evaluating interdisciplinary activities involving the subject of mathematics and philosophy in the high schools. Through the terms...... of Horizontal Intertwining, Vertical Structuring and Horizontal Propagation the model consists of three phases, each considering different aspects of the nature of interdisciplinary activities. The theoretical modelling is inspired by work which focuses on the students abilities to concept formation in expanded...... domains (Michelsen, 2001, 2005a, 2005b). Furthermore the theoretical description rest on a series of qualitative interviews with teachers from the Danish high school (grades 9-11) conducted recently. The special case of concrete interdisciplinary activities between mathematics and philosophy is also...

  1. Comparison of activity coefficient models for electrolyte systems

    DEFF Research Database (Denmark)

    Lin, Yi; ten Kate, Antoon; Mooijer, Miranda

    2010-01-01

    Three activity coefficient models for electrolyte solutions were evaluated and compared. The activity coefficient models are: The electrolyte NRTL model (ElecNRTL) by Aspentech, the mixed solvent electrolyte model (MSE) by OLI Systems Inc., and the Extended UNIQUAC model from the Technical Univer...

  2. Comparative anthelmintic activity investigation of selected ethno-medicinal weeds

    Science.gov (United States)

    Pueblos, Kirstin Rhys S.; Bajalla, Mark; Pacheco, Dixie; Ganot, Sheila; Paig, Daisy; Tapales, Radyn; Lagare, Jeanne; Quimque, Mark Tristan J.

    2017-01-01

    Helminth infections are one of the seriously neglected potent diseases in many parts of the world. The problems of parasitic helminthes becoming resistant to currently available anthelmintic drugs pose a challenge for the search - relying on natural products - for new and better anthelmintics. In this paper, four abundant Philippine weeds: Chrysopogon aciculatus Trin. Cyperus brevifolius Rottb., Ruellia tuberosa Linn. and Saccharum spontaneum Linn. were investigated for their anthelmintic activities to establish basis of their folkloric claim. The hexane-soluble and chloroform-soluble extracts were obtained through sequential solvent partitioning of the crude ethanolic extract of the air-dried aerial part of each plant sample. Meanwhile, the decoction was obtained from fresh aerial part of the plant samples. All extracts were then subjected to in vitro anthelmintic screening at different concentration as per method of Ghosh, et al. against African nightcrawler earthworms (Eudrillus euginiae) in which the activity of the extracts was determined by correlation with time. The anthelmintic bioassay results revealed a dose-dependent toxicity relationship. It indicated relatively low anthelmintic activities of the decoction of the four plant samples as compared to their corresponding crude ethanol extracts. Among the crude ethanol extracts, C. brevifolius (CBE) gave fastest time to bring about paralysis and death to the test organisms at all concentrations tested. For the hexane extracts, R. tuberosa (RTH) gave better activity among other plant samples. Lastly, among the chloroform-soluble extracts, both that of C. brevifolius (CBC) and R. tuberosa (RTC) comparably showed strongest anthelmintic activities at all tested concentrations, thus, exhibited best anthelmintic activity that is remarkably comparable to the positive control, Mebendazole at the highest concentration tested. In fact, CBC and RTC showed highest anthelmintic potential compared to all extracts tested in

  3. Comparing Poisson Sigma Model with A-model

    Science.gov (United States)

    Bonechi, F.; Cattaneo, A. S.; Iraso, R.

    2016-10-01

    We discuss the A-model as a gauge fixing of the Poisson Sigma Model with target a symplectic structure. We complete the discussion in [4], where a gauge fixing defined by a compatible complex structure was introduced, by showing how to recover the A-model hierarchy of observables in terms of the AKSZ observables. Moreover, we discuss the off-shell supersymmetry of the A-model as a residual BV symmetry of the gauge fixed PSM action.

  4. Comparing model predictions for ecosystem-based management

    DEFF Research Database (Denmark)

    Jacobsen, Nis Sand; Essington, Timothy E.; Andersen, Ken Haste

    2016-01-01

    Ecosystem modeling is becoming an integral part of fisheries management, but there is a need to identify differences between predictions derived from models employed for scientific and management purposes. Here, we compared two models: a biomass-based food-web model (Ecopath with Ecosim (Ew......E)) and a size-structured fish community model. The models were compared with respect to predicted ecological consequences of fishing to identify commonalities and differences in model predictions for the California Current fish community. We compared the models regarding direct and indirect responses to fishing...... on one or more species. The size-based model predicted a higher fishing mortality needed to reach maximum sustainable yield than EwE for most species. The size-based model also predicted stronger top-down effects of predator removals than EwE. In contrast, EwE predicted stronger bottom-up effects...

  5. Comparing SVARs and SEMs : Two models of the UK economy

    NARCIS (Netherlands)

    Jacobs, J.P.A.M.; Wallis, K.F.

    2005-01-01

    The structural vector autoregression (SVAR) and simultaneous equation macroeconometric model (SEM) styles of empirical macroeconomic modelling are compared and contrasted, with reference to two models of the UK economy, namely the long-run structural VAR model of Garratt, Lee, Pesaran and Shin and t

  6. Evolution and physics in comparative protein structure modeling.

    Science.gov (United States)

    Fiser, András; Feig, Michael; Brooks, Charles L; Sali, Andrej

    2002-06-01

    From a physical perspective, the native structure of a protein is a consequence of physical forces acting on the protein and solvent atoms during the folding process. From a biological perspective, the native structure of proteins is a result of evolution over millions of years. Correspondingly, there are two types of protein structure prediction methods, de novo prediction and comparative modeling. We review comparative protein structure modeling and discuss the incorporation of physical considerations into the modeling process. A good starting point for achieving this aim is provided by comparative modeling by satisfaction of spatial restraints. Incorporation of physical considerations is illustrated by an inclusion of solvation effects into the modeling of loops.

  7. Comparing Pedophile Activity in Different P2P Systems

    OpenAIRE

    Raphaël Fournier; Thibault Cholez; Matthieu Latapy; Isabelle Chrisment; Clémence Magnien; Olivier Festor; Ivan Daniloff

    2014-01-01

    International audience; Peer-to-peer (P2P) systems are widely used to exchange content over the Internet. Knowledge of pedophile activity in such networks remains limited, despite having important social consequences. Moreover, though there are different P2P systems in use, previous academic works on this topic focused on one system at a time and their results are not directly comparable. We design a methodology for comparing KAD and eDonkey, two P2P systems among the most prominent ones and ...

  8. Comparing Poisson Sigma Model with A-model

    CERN Document Server

    Bonechi, Francesco; Iraso, Riccardo

    2016-01-01

    We discuss the A-model as a gauge fixing of the Poisson Sigma Model with target a symplectic structure. We complete the discussion in [arXiv:0706.3164], where a gauge fixing defined by a compatible complex structure was introduced, by showing how to recover the A-model hierarchy of observables in terms of the AKSZ observables. Moreover, we discuss the off-shell supersymmetry of the A-model as a residual BV symmetry of the gauge-fixed PSM action.

  9. Modeling interdisciplinary activities involving Mathematics

    DEFF Research Database (Denmark)

    Iversen, Steffen Møllegaard

    2006-01-01

    In this paper a didactical model is presented. The goal of the model is to work as a didactical tool, or conceptual frame, for developing, carrying through and evaluating interdisciplinary activities involving the subject of mathematics and philosophy in the high schools. Through the terms...... domains (Michelsen, 2001, 2005a, 2005b). Furthermore the theoretical description rest on a series of qualitative interviews with teachers from the Danish high school (grades 9-11) conducted recently. The special case of concrete interdisciplinary activities between mathematics and philosophy is also...

  10. Modeling Cytoskeletal Active Matter Systems

    Science.gov (United States)

    Blackwell, Robert

    Active networks of filamentous proteins and crosslinking motor proteins play a critical role in many important cellular processes. One of the most important microtubule-motor protein assemblies is the mitotic spindle, a self-organized active liquid-crystalline structure that forms during cell division and that ultimately separates chromosomes into two daughter cells. Although the spindle has been intensively studied for decades, the physical principles that govern its self-organization and function remain mysterious. To evolve a better understanding of spindle formation, structure, and dynamics, I investigate course-grained models of active liquid-crystalline networks composed of microtubules, modeled as hard spherocylinders, in diffusive equilibrium with a reservoir of active crosslinks, modeled as hookean springs that can adsorb to microtubules and and translocate at finite velocity along the microtubule axis. This model is investigated using a combination of brownian dynamics and kinetic monte carlo simulation. I have further refined this model to simulate spindle formation and kinetochore capture in the fission yeast S. pombe. I then make predictions for experimentally realizable perturbations in motor protein presence and function in S. pombe.

  11. Comparing Productivity Simulated with Inventory Data Using Different Modelling Technologies

    Science.gov (United States)

    Klopf, M.; Pietsch, S. A.; Hasenauer, H.

    2009-04-01

    The Lime Stone National Park in Austria was established in 1997 to protect sensible lime stone soils from degradation due to heavy forest management. Since 1997 the management activities were successively reduced and standing volume and coarse woody debris (CWD) increased and degraded soils began to recover. One option to study the rehabilitation process towards natural virgin forest state is the use of modelling technology. In this study we will test two different modelling approaches for their applicability to Lime Stone National Park. We will compare standing tree volume simulated resulting from (i) the individual tree growth model MOSES, and (ii) the species and management sensitive adaptation of the biogeochemical-mechanistic model Biome-BGC. The results from the two models are compared with filed observations form repeated permanent forest inventory plots of the Lime Stone National Park in Austria. The simulated CWD predictions of the BGC-model were compared with dead wood measurements (standing and lying dead wood) recorded at the permanent inventory plots. The inventory was established between 1994 and 1996 and remeasured from 2004 to 2005. For this analysis 40 plots of this inventory were selected which comprise the required dead wood components and are dominated by a single tree species. First we used the distance dependant individual tree growth model MOSES to derive the standing timber and the amount of mortality per hectare. MOSES is initialized with the inventory data at plot establishment and each sampling plot is treated as forest stand. The Biome-BGC is a process based biogeochemical model with extensions for Austrian tree species, a self initialization and a forest management tool. The initialization for the actual simulations with the BGC model was done as follows: We first used spin up runs to derive a balanced forest vegetation, similar to an undisturbed forest. Next we considered the management history of the past centuries (heavy clear cuts

  12. Theory-based Practice: Comparing and Contrasting OT Models

    DEFF Research Database (Denmark)

    Nielsen, Kristina Tomra; Berg, Brett

    2012-01-01

    Theory- Based Practice: Comparing and Contrasting OT Models The workshop will present a critical analysis of the major models of occupational therapy, A Model of Human Occupation, Enabling Occupation II, and Occupational Therapy Intervention Process Model. Similarities and differences among...... the models will be discussed, including each model’s limitations and unique contributions to the profession. Workshop format will include short lectures and group discussions....

  13. Comparative activity of carbapenem testing (the COMPACT study in Turkey

    Directory of Open Access Journals (Sweden)

    Leblebicioglu Hakan

    2012-02-01

    Full Text Available Abstract Background Recent evidence indicates that Gram-negative bacterial pathogens, the most common of which are Pseudomonas spp., Enterobacteriaceae, and Acinetobacter baumannii, are frequent causes of hospital-acquired infections. This study aims to evaluate the in vitro activity of doripenem and comparator carbapenem antibiotics against Gram-negative clinical isolates collected from COMParative Activity of Carbapenem Testing (COMPACT study centres in Turkey. Methods Ten centres in Turkey were invited to submit Pseudomonas aeruginosa, Enterobacteriaceae, and other Gram-negative isolates from intensive care unit (ICU/non-ICU patients with complicated intra-abdominal infections, bloodstream infections, or nosocomial pneumonia, including ventilator-associated pneumonia, between May and October 2008. Susceptibility was determined by each centre using E-test. A central laboratory performed species confirmation as well as limited susceptibility and quality-control testing. Results Five hundred and ninety six isolates were collected. MIC90 values for doripenem, meropenem, and imipenem, respectively, were 32, ≥ 64, and ≥ 64 mg/L against Pseudomonas spp.; 0.12, 0.12, and 0.5 mg/L against Enterobacteriaceae; and ≥ 64 mg/L for each against other Gram-negative isolates. In determining the susceptibility of hospital isolates of selected Gram-negative pathogens to doripenem, imipenem, and meropenem, we found that against all pathogens combined, the MIC90 for ICU compared with non-ICU isolates was higher. Conclusions Doripenem showed similar or slightly better activity than meropenem and better activity than imipenem against the Gram-negative pathogens collected in Turkey.

  14. Active Learning for Player Modeling

    DEFF Research Database (Denmark)

    Shaker, Noor; Abou-Zleikha, Mohamed; Shaker, Mohammad

    2015-01-01

    Learning models of player behavior has been the focus of several studies. This work is motivated by better understanding of player behavior, a knowledge that can ultimately be employed to provide player-adapted or personalized content. In this paper, we propose the use of active learning for player...... experience modeling. We use a dataset from hundreds of players playing Infinite Mario Bros. as a case study and we employ the random forest method to learn mod- els of player experience through the active learning approach. The results obtained suggest that only part of the dataset (up to half the size...... of the full dataset) is necessary for the construction of accu- rate models that are as accurate as those constructed from the full dataset. This indicates the potential of the method and its benefits in cases when obtaining the data is expensive or time, storage or effort consuming. The results also indicate...

  15. Active Learning for Player Modeling

    DEFF Research Database (Denmark)

    Shaker, Noor; Abou-Zleikha, Mohamed; Shaker, Mohammad

    2015-01-01

    Learning models of player behavior has been the focus of several studies. This work is motivated by better understanding of player behavior, a knowledge that can ultimately be employed to provide player-adapted or personalized content. In this paper, we propose the use of active learning for player...... experience modeling. We use a dataset from hundreds of players playing Infinite Mario Bros. as a case study and we employ the random forest method to learn mod- els of player experience through the active learning approach. The results obtained suggest that only part of the dataset (up to half the size...... of the full dataset) is necessary for the construction of accu- rate models that are as accurate as those constructed from the full dataset. This indicates the potential of the method and its benefits in cases when obtaining the data is expensive or time, storage or effort consuming. The results also indicate...

  16. Comparing models of star formation simulating observed interacting galaxies

    Science.gov (United States)

    Quiroga, L. F.; Muñoz-Cuartas, J. C.; Rodrigues, I.

    2017-07-01

    In this work, we make a comparison between different models of star formation to reproduce observed interacting galaxies. We use observational data to model the evolution of a pair of galaxies undergoing a minor merger. Minor mergers represent situations weakly deviated from the equilibrium configuration but significant changes in star fomation (SF) efficiency can take place, then, minor mergers provide an unique scene to study SF in galaxies in a realistic but yet simple way. Reproducing observed systems also give us the opportunity to compare the results of the simulations with observations, which at the end can be used as probes to characterize the models of SF implemented in the comparison. In this work we compare two different star formation recipes implemented in Gadget3 and GIZMO codes. Both codes share the same numerical background, and differences arise mainly in the star formation recipe they use. We use observations from Pico dos Días and GEMINI telescopes and show how we use observational data of the interacting pair in AM2229-735 to characterize the interacting pair. Later we use this information to simulate the evolution of the system to finally reproduce the observations: Mass distribution, morphology and main features of the merger-induced star formation burst. We show that both methods manage to reproduce roughly the star formation activity. We show, through a careful study, that resolution plays a major role in the reproducibility of the system. In that sense, star formation recipe implemented in GIZMO code has shown a more robust performance. Acknowledgements: This work is supported by Colciencias, Doctorado Nacional - 617 program.

  17. Parmodel: a web server for automated comparative modeling of proteins.

    Science.gov (United States)

    Uchôa, Hugo Brandão; Jorge, Guilherme Eberhart; Freitas Da Silveira, Nelson José; Camera, João Carlos; Canduri, Fernanda; De Azevedo, Walter Filgueira

    2004-12-24

    Parmodel is a web server for automated comparative modeling and evaluation of protein structures. The aim of this tool is to help inexperienced users to perform modeling, assessment, visualization, and optimization of protein models as well as crystallographers to evaluate structures solved experimentally. It is subdivided in four modules: Parmodel Modeling, Parmodel Assessment, Parmodel Visualization, and Parmodel Optimization. The main module is the Parmodel Modeling that allows the building of several models for a same protein in a reduced time, through the distribution of modeling processes on a Beowulf cluster. Parmodel automates and integrates the main softwares used in comparative modeling as MODELLER, Whatcheck, Procheck, Raster3D, Molscript, and Gromacs. This web server is freely accessible at .

  18. Comparing Structural Brain Connectivity by the Infinite Relational Model

    DEFF Research Database (Denmark)

    Ambrosen, Karen Marie Sandø; Herlau, Tue; Dyrby, Tim;

    2013-01-01

    The growing focus in neuroimaging on analyzing brain connectivity calls for powerful and reliable statistical modeling tools. We examine the Infinite Relational Model (IRM) as a tool to identify and compare structure in brain connectivity graphs by contrasting its performance on graphs from...... modeling tool for the identification of structure and quantification of similarity in graphs of brain connectivity in general....

  19. Synthesis and comparing the antibacterial activities of pyrimidine derivatives

    Indian Academy of Sciences (India)

    B ANDREWS; K KOMATHI; S MOHAN

    2017-03-01

    A series of 10 derivatives of 5-(5-amino-1,3,4-thiadiazole-2-yl)-3,4-dihydro-6-methyl-4-phenylpyrimidin-2(1H)-one and 10 derivatives of 3,4-dihydro-5-(5-mercapto-4H-1,2,4-triazol-3-yl)-6-methyl-4-phenyl pyrimidin-2(1H)-one have been synthesized. Among the synthesized derivatives, triazole substitutedcompounds have shown higher antibacterial inhibition when compared to the thiadiazole derivatives. All the structures of the newly synthesized compounds have been characterized by IR, 1H and 13C NMR, GC-MS and CHN analysis. Most of the compounds have shown promising antibacterial activity when compared with the standard drug ciprofloxacin.

  20. Piezoelectric ceramic fibers for active fiber composites: a comparative study

    Science.gov (United States)

    Kornmann, Xavier; Huber, Christian; Elsener, Hans-Rudolf

    2003-08-01

    The morphology and the free strain performances of three different piezoelectric ceramic fibers used for the manufacture of active fiber composites (AFCs) have been investigated. The morphology of the fibers has a direct influence on the manufacture of the AFCs. Fibers with non-uniform diameters are more difficult to contact with the interdigitated electrodes and can be the cause of irreparable damages in AFCs. An indirect method requiring the use of a simple analytical model is proposed to evaluate the free strain of active fiber composites. This indirect method presents a relatively good agreement with direct free strain measurements performed with strain gages glued on both sides of an AFC. The results show a systematic difference of ca. 20 % between the indirect and the direct methods. However, the indirect method did not permit to see differences of piezoelectric performance between the types of fibers.

  1. Comparative Study of Various SDLC Models on Different Parameters

    Directory of Open Access Journals (Sweden)

    Prateek Sharma

    2015-04-01

    Full Text Available The success of a software development project greatly depends upon which process model is used. This paper emphasizes on the need of using appropriate model as per the application to be developed. In this paper we have done the comparative study of the following software models namely Waterfall, Prototype, RAD (Rapid Application Development Incremental, Spiral, Build and Fix and V-shaped. Our aim is to create reliable and cost effective software and these models provide us a way to develop them. The main objective of this research is to represent different models of software development and make a comparison between them to show the features of each model.

  2. Healing of complement activating Ti implants compared with non-activating Ti in rat tibia.

    Science.gov (United States)

    Harmankaya, N; Igawa, K; Stenlund, P; Palmquist, A; Tengvall, P

    2012-09-01

    Recent studies have revealed that ozone ultraviolet (UVO) illumination of titanium (Ti) implants improves bone-implant anchorage by altering the physico-chemical and immune activating properties of the titanium dioxide (TiO(2)) layer. In the present rat tibia model, the authors compared the early events of inflammation and bone formation around UVO-treated Ti and complement activating immunoglobin g (IgG)-coated Ti. Machined Ti and machined Ti coated with a physical vapour-deposited Ti layer were used as references. Screw-shaped test and reference implants were implanted into rat tibia and harvested after 1, 7 and 28 days. Messenger RNA expression of implant adhered cells and peri-implant tissue ~250 μm from the surface were subsequently analysed with regard to IL-1β, TNF-α, osteocalcin, cathepsin K, BMP-2 and PDGF. Separate implants were retrieved after 7 and 28 days for removal torque measurements, and histological staining and histomorphometric analysis of bone area and bone-to-implant contact. While enhanced expression of inflammatory markers, TNF-α and IL-1β, was observed on IgG-coated surfaces throughout the observation time, UVO-treated surfaces indicated a significantly lower early inflammatory response. In the early phases (1 and 7 days), the UVO-treated surfaces displayed a significantly higher expression of osteoblast markers BMP-2 and osteocalcin. In summary, complement activating Ti implants elicited a stronger inflammatory response than UVO-treated Ti, with low complement activation during the first week of healing. In spite of this, the UVO-treated Ti induced only marginally more bone growth outside the implants.

  3. Comparing Pedophile Activity in Different P2P Systems

    Directory of Open Access Journals (Sweden)

    Raphaël Fournier

    2014-07-01

    Full Text Available Peer-to-peer (P2P systems are widely used to exchange content over the Internet. Knowledge of pedophile activity in such networks remains limited, despite having important social consequences. Moreover, though there are different P2P systems in use, previous academic works on this topic focused on one system at a time and their results are not directly comparable. We design a methodology for comparing KAD and eDonkey, two P2P systems among the most prominent ones and with different anonymity levels. We monitor two eDonkey servers and the KAD network during several days and record hundreds of thousands of keyword-based queries. We detect pedophile-related queries with a previously validated tool and we propose, for the first time, a large-scale comparison of pedophile activity in two different P2P systems. We conclude that there are significantly fewer pedophile queries in KAD than in eDonkey (approximately 0.09% vs. 0.25%.

  4. Comparative Performance of Volatility Models for Oil Price

    Directory of Open Access Journals (Sweden)

    Afees A. Salisu

    2012-07-01

    Full Text Available In this paper, we compare the performance of volatility models for oil price using daily returns of WTI. The innovations of this paper are in two folds: (i we analyse the oil price across three sub samples namely period before, during and after the global financial crisis, (ii we also analyse the comparative performance of both symmetric and asymmetric volatility models for the oil price. We find that oil price was most volatile during the global financial crises compared to other sub samples. Based on the appropriate model selection criteria, the asymmetric GARCH models appear superior to the symmetric ones in dealing with oil price volatility. This finding indicates evidence of leverage effects in the oil market and ignoring these effects in oil price modelling will lead to serious biases and misleading results.

  5. Comparing various multi-component global heliosphere models

    CERN Document Server

    Müller, H -R; Heerikhuisen, J; Izmodenov, V V; Scherer, K; Alexashov, D; Fahr, H -J

    2008-01-01

    Modeling of the global heliosphere seeks to investigate the interaction of the solar wind with the partially ionized local interstellar medium. Models that treat neutral hydrogen self-consistently and in great detail, together with the plasma, but that neglect magnetic fields, constitute a sub-category within global heliospheric models. There are several different modeling strategies used for this sub-category in the literature. Differences and commonalities in the modeling results from different strategies are pointed out. Plasma-only models and fully self-consistent models from four research groups, for which the neutral species is modeled with either one, three, or four fluids, or else kinetically, are run with the same boundary parameters and equations. They are compared to each other with respect to the locations of key heliospheric boundary locations and with respect to the neutral hydrogen content throughout the heliosphere. In many respects, the models' predictions are similar. In particular, the loca...

  6. Modeling electrically active viscoelastic membranes.

    Directory of Open Access Journals (Sweden)

    Sitikantha Roy

    Full Text Available The membrane protein prestin is native to the cochlear outer hair cell that is crucial to the ear's amplification and frequency selectivity throughout the whole acoustic frequency range. The outer hair cell exhibits interrelated dimensional changes, force generation, and electric charge transfer. Cells transfected with prestin acquire unique active properties similar to those in the native cell that have also been useful in understanding the process. Here we propose a model describing the major electromechanical features of such active membranes. The model derived from thermodynamic principles is in the form of integral relationships between the history of voltage and membrane resultants as independent variables and the charge density and strains as dependent variables. The proposed model is applied to the analysis of an active force produced by the outer hair cell in response to a harmonic electric field. Our analysis reveals the mechanism of the outer hair cell active (isometric force having an almost constant amplitude and phase up to 80 kHz. We found that the frequency-invariance of the force is a result of interplay between the electrical filtering associated with prestin and power law viscoelasticity of the surrounding membrane. Paradoxically, the membrane viscoelasticity boosts the force balancing the electrical filtering effect. We also consider various modes of electromechanical coupling in membrane with prestin associated with mechanical perturbations in the cell. We consider pressure or strains applied step-wise or at a constant rate and compute the time course of the resulting electric charge. The results obtained here are important for the analysis of electromechanical properties of membranes, cells, and biological materials as well as for a better understanding of the mechanism of hearing and the role of the protein prestin in this mechanism.

  7. Reciprocal Ontological Models Show Indeterminism Comparable to Quantum Theory

    Science.gov (United States)

    Bandyopadhyay, Somshubhro; Banik, Manik; Bhattacharya, Some Sankar; Ghosh, Sibasish; Kar, Guruprasad; Mukherjee, Amit; Roy, Arup

    2016-12-01

    We show that within the class of ontological models due to Harrigan and Spekkens, those satisfying preparation-measurement reciprocity must allow indeterminism comparable to that in quantum theory. Our result implies that one can design quantum random number generator, for which it is impossible, even in principle, to construct a reciprocal deterministic model.

  8. Reciprocal Ontological Models Show Indeterminism Comparable to Quantum Theory

    Science.gov (United States)

    Bandyopadhyay, Somshubhro; Banik, Manik; Bhattacharya, Some Sankar; Ghosh, Sibasish; Kar, Guruprasad; Mukherjee, Amit; Roy, Arup

    2017-02-01

    We show that within the class of ontological models due to Harrigan and Spekkens, those satisfying preparation-measurement reciprocity must allow indeterminism comparable to that in quantum theory. Our result implies that one can design quantum random number generator, for which it is impossible, even in principle, to construct a reciprocal deterministic model.

  9. A Mathematical Model for Comparing Holland's Personality and Environmental Codes.

    Science.gov (United States)

    Kwak, Junkyu Christopher; Pulvino, Charles J.

    1982-01-01

    Presents a mathematical model utilizing three-letter codes of personality patterns determined from the Self Directed Search. This model compares personality types over time or determines relationships between personality types and person-environment interactions. This approach is consistent with Holland's theory yet more comprehensive than one- or…

  10. Comparative Analysis of Uncertainties in Urban Surface Runoff Modelling

    DEFF Research Database (Denmark)

    Thorndahl, Søren; Schaarup-Jensen, Kjeld

    2007-01-01

    In the present paper a comparison between three different surface runoff models, in the numerical urban drainage tool MOUSE, is conducted. Analysing parameter uncertainty, it is shown that the models are very sensitive with regards to the choice of hydrological parameters, when combined overflow...... analysis, further research in improved parameter assessment for surface runoff models is needed....... volumes are compared - especially when the models are uncalibrated. The occurrences of flooding and surcharge are highly dependent on both hydrological and hydrodynamic parameters. Thus, the conclusion of the paper is that if the use of model simulations is to be a reliable tool for drainage system...

  11. Comparative analysis of model assessment in community detection

    CERN Document Server

    Kawamoto, Tatsuro

    2016-01-01

    Bayesian cluster inference with a flexible generative model allows us to detect various types of structures. However, it has problems stemming from computational complexity and difficulties in model assessment. We consider the stochastic block model with restricted hyperparameter space, which is known to correspond to modularity maximization. We show that it not only reduces computational complexity, but is also beneficial for model assessment. Using various criteria, we conduct a comparative analysis of the model assessments, and analyze whether each criterion tends to overfit or underfit. We also show that the learning of hyperparameters leads to qualitative differences in Bethe free energy and cross-validation errors.

  12. Comparative Study of Path Loss Models in Different Environments

    Directory of Open Access Journals (Sweden)

    Tilotma Yadav,

    2011-04-01

    Full Text Available By using propagation path models to estimate the received signal level as a function of distance, it becomes possible to predict the SNR for a mobile communication system. Both theoretical andmeasurement-based propagation models indicate that average received signal power decreases logarithmically with distance. For comparative analysis we use Okumura’s model, Hata model, COST231 Extension to Hata model,ECEC-33 model,SUI model along with the practical data. Most of these models are based on a systematic interpretation of theoretical data service area like urban(Built-up city or largetown crowded with large buildings, suburban (having some obstacles near the mobile radio car, but still not very congested and rural (No obstacles like tall trees or buildings like farm-land, rice field, open fields in INDIA at 900MHz & 1800MHz frequency .

  13. Comparing measured and modeled firn compaction rates in Greenland

    Science.gov (United States)

    Stevens, C.; MacFerrin, M. J.; Waddington, E. D.; Vo, H.; Yoon, M.

    2015-12-01

    Quantifying the mass balance of the Greenland and Antarctic ice sheets using satellite and/or airborne altimetry requires a firn-densification model to correct for firn-air content and transient firn-thickness changes. We have developed the Community Firn Model (CFM) that allows users to run firn-densification physics from a suite of published models. Here, we use the CFM to compare model-predicted firn depth-density profiles and compaction rates with observed profiles and compaction rates collected from a network of in situ strain gauges at eight different sites in Greenland. Additionally, we use regional-climate-model output to force the CFM and compare the depth-density profiles and compaction rates predicted by the different models. Many of the models were developed using a steady-state assumption and were tuned for the dry-snow zone. Our results demonstrate the challenges of using these models to simulate firn density in Greenland's expanding wet firn and percolation zones, and they help quantify the uncertainty in firn-density model predictions. Next-generation firn models are incorporating more physics (e.g. meltwater percolation and grain growth), and field measurements are essential to inform continuing development of these new models.

  14. A COMPARATIVE STUDY OF BACTERIOSTATIC ACTIVITY OF SYNTHETIC HYDROXYLATED FLAVONOIDS

    Directory of Open Access Journals (Sweden)

    Olivella Mónica S.

    2001-01-01

    Full Text Available Among other properties, flavonoids present a notable bacteriostatic activity. In this paper, minimal inhibitory concentrations (MICs of 5,7,4'-trihydroxyflavanone (naringenin, 5,7-dihydroxyflavone and 2',4',4- trihydroxychalcone (isoliquitirigenin against Staphylococcus aureus ATCC 25 923 were determined and compared to values obtained for other chalcones and flavanones previously investigated. Specific growth rates and MICs were determined by a turbidimetric kinetic method. The observed sequence MICflavanone (inactive >MIC7-hidroxyflavanone (197.6 µgml-1>MIC5,7,4'-trihydroxyflavanone (120 µgml-1 showed that the introduction of an electron donating group (-OH causes an increase in bioactivity. On the other hand, the comparisons MIC5,7,4'-trihydroxyflavanone (120 µgml-1 >>> MIC2',4',4-trihydroxychalcone (29 µgml-1 and MIC5,7-dihydroxyflavone (105 µgml-1 >>> MIC2',4'-dihydroxychalcone (28.8 µgml-1 indicated that the chalcone structure is the most favourable for bacteriostatic activity within the flavonoid family.

  15. Comparative analysis of marine ecosystems: international production modelling workshop.

    Science.gov (United States)

    Link, Jason S; Megrey, Bernard A; Miller, Thomas J; Essington, Tim; Boldt, Jennifer; Bundy, Alida; Moksness, Erlend; Drinkwater, Ken F; Perry, R Ian

    2010-12-23

    Understanding the drivers that dictate the productivity of marine ecosystems continues to be a globally important issue. A vast literature identifies three main processes that regulate the production dynamics of such ecosystems: biophysical, exploitative and trophodynamic. Exploring the prominence among this 'triad' of drivers, through a synthetic analysis, is critical for understanding how marine ecosystems function and subsequently produce fisheries resources of interest to humans. To explore this topic further, an international workshop was held on 10-14 May 2010, at the National Academy of Science's Jonsson Center in Woods Hole, MA, USA. The workshop compiled the data required to develop production models at different hierarchical levels (e.g. species, guild, ecosystem) for many of the major Northern Hemisphere marine ecosystems that have supported notable fisheries. Analyses focused on comparable total system biomass production, functionally equivalent species production, or simulation studies for 11 different marine fishery ecosystems. Workshop activities also led to new analytical tools. Preliminary results suggested common patterns driving overall fisheries production in these ecosystems, but also highlighted variation in the relative importance of each among ecosystems.

  16. Active synthesis of multiaxial drive systems using a comparative method

    Directory of Open Access Journals (Sweden)

    T. Dzitkowski

    2011-12-01

    Full Text Available Purpose: of this paper is the problem of stability and vibration reduction in designed drive systems, in which the essential requirement is to meet the desired dynamic properties.Design/methodology/approach: : The method of stabilisation and reduction has been based on active synthesis, which makes it possible to obtain the desired mechanical effect through the proper selection of dynamic properties of the system, including the calculation of the active force as a function of the system force feedback.Findings: Presented approach simplifies the process of selecting the dynamical parameters of machine drive systems in view of their dynamical characteristics.Research limitations/implications: The scope of discussion is the synthesis of machine drive systems as discrete models of torsional vibrations. Such vibrations are more difficult to detect than flexural ones, which are accompanied by noise and vibrations of the adjacent elements (for example, shaft frames. Due to the absence of symptoms, torsional vibrations are particularly dangerous, as they may be unnoticeable until the destruction of subsystems occurs.Practical implications: High durability and reliability of drive systems is associated with proper setting of system parameters - inertial, elastical and damping. Proper setting of these parameters is made possible by applying synthesis techniques.Originality/value: We should emphasize that the considered problem varies from other issues met in classic mechanics or control theory. The research has been undertaken on the basis of topological methods, developed in scholar environment of Gliwice.

  17. Comparative study to predict dipeptidyl peptidase IV inhibitory activity of β-amino amide scaffold

    Directory of Open Access Journals (Sweden)

    S Patil

    2015-01-01

    Full Text Available Comparative study was performed on 34 β-amino amide derivatives as dipeptidyl peptidase IV inhibitors in order to determine their structural requirement to enhance the antidiabetic activities. Hologram quantitative structure activity relationships models utilized specialized fragment fingerprints (hologram length 353 which showed good predictivity with cross-validated q 2 and conventional r 2 values of 0.971 and 0.971, respectively. Models were validated and optimized by a test set of eight compounds and gave satisfactory predictive ability. Hologram quantitative structure activity relationships maps were helpful in prediction of the structural features of the ligands to account for the activity in terms of positively and negatively contributing towards activity. The information obtained from maps could be effectively use as a guiding tool for further structure modifications and synthesis of new potent antidiabetic agents.

  18. Proliferative activity in oral pyogenic granuloma: A comparative immunohistochemical study

    Directory of Open Access Journals (Sweden)

    Rezvani Gita

    2010-07-01

    Full Text Available Context: Pyogenic granuloma (PG is one of the most common reactive vascular lesions in the oral mucosa, which has been divided into the lobular capillary hemangioma (LCH and the non lobular type (non-LCH as two distinct entities, on the basis of some investigations. Aims: This study aims to compare the proliferative and angiogenic activity of two histological types of PG to determine whether they have two distinct types of biological behavior. Settings and Design: In this retrospective cross-sectional study, immunostaining was performed on 10 cases of each type of PG. Materials and Methods: About 4μm sections were cut from formalin-fixed paraffin-embedded blocks and each specimen was stained with both anti-CD31 and anti-Ki-67 antibodies simultaneously. Labeling index (LI was determined for both types by counting Ki-67 and CD31 positive cells separately and simultaneously in 1000 stromal and luminal cells. Micro vessel count (MVC, the mean number of micro vessels in five areas at Χ200 magnification, was also determined for both groups. Statistical Analysis: The results were statistically compared using the Mann-Whitney U-test. Results: Ki-67 LI in LCH (5.4 ± 2.4 was higher than non-LCH (3.9 ± 3.9. The percentage of CD31 positive cells in LCH (28.5 ± 22 was lower than non-LCH (37.1 ± 20.8 and simultaneously immunostaining for both markers in LCH type (2.4 ± 2.1 was higher than non-LCH (1.2 ± 1. The MVC was approximately 77.35 ± 34.6 and 82.6 ± 42.7 in the lobular areas of LCH and central areas of non-LCH PG, respectively. These differences were not statistically significant. Conclusions: These results demonstrate a higher proliferation activity in endothelial cells of LCH PG than in non-LCH.

  19. Disaggregation of Rainy Hours: Compared Performance of Various Models.

    Science.gov (United States)

    Ben Haha, M.; Hingray, B.; Musy, A.

    In the urban environment, the response times of catchments are usually short. To de- sign or to diagnose waterworks in that context, it is necessary to describe rainfall events with a good time resolution: a 10mn time step is often necessary. Such in- formation is not always available. Rainfall disaggregation models have thus to be applied to produce from rough rainfall data that short time resolution information. The communication will present the performance obtained with several rainfall dis- aggregation models that allow for the disaggregation of rainy hours into six 10mn rainfall amounts. The ability of the models to reproduce some statistical character- istics of rainfall (mean, variance, overall distribution of 10mn-rainfall amounts; ex- treme values of maximal rainfall amounts over different durations) is evaluated thanks to different graphical and numerical criteria. The performance of simple models pre- sented in some scientific papers or developed in the Hydram laboratory as well as the performance of more sophisticated ones is compared with the performance of the basic constant disaggregation model. The compared models are either deterministic or stochastic; for some of them the disaggregation is based on scaling properties of rainfall. The compared models are in increasing complexity order: constant model, linear model (Ben Haha, 2001), Ormsbee Deterministic model (Ormsbee, 1989), Ar- tificial Neuronal Network based model (Burian et al. 2000), Hydram Stochastic 1 and Hydram Stochastic 2 (Ben Haha, 2001), Multiplicative Cascade based model (Olsson and Berndtsson, 1998), Ormsbee Stochastic model (Ormsbee, 1989). The 625 rainy hours used for that evaluation (with a hourly rainfall amount greater than 5mm) were extracted from the 21 years chronological rainfall series (10mn time step) observed at the Pully meteorological station, Switzerland. The models were also evaluated when applied to different rainfall classes depending on the season first and on the

  20. Comparative Analysis of Vehicle Make and Model Recognition Techniques

    Directory of Open Access Journals (Sweden)

    Faiza Ayub Syed

    2014-03-01

    Full Text Available Vehicle Make and Model Recognition (VMMR has emerged as a significant element of vision based systems because of its application in access control systems, traffic control and monitoring systems, security systems and surveillance systems, etc. So far a number of techniques have been developed for vehicle recognition. Each technique follows different methodology and classification approaches. The evaluation results highlight the recognition technique with highest accuracy level. In this paper we have pointed out the working of various vehicle make and model recognition techniques and compare these techniques on the basis of methodology, principles, classification approach, classifier and level of recognition After comparing these factors we concluded that Locally Normalized Harris Corner Strengths (LHNS performs best as compared to other techniques. LHNS uses Bayes and K-NN classification approaches for vehicle classification. It extracts information from frontal view of vehicles for vehicle make and model recognition.

  1. Comparative Analysis of Dayside Reconnection Models in Global Magnetosphere Simulations

    CERN Document Server

    Komar, C M; Cassak, P A

    2015-01-01

    We test and compare a number of existing models predicting the location of magnetic reconnection at Earth's dayside magnetopause for various solar wind conditions. We employ robust image processing techniques to determine the locations where each model predicts reconnection to occur. The predictions are then compared to the magnetic separators, the magnetic field lines separating different magnetic topologies. The predictions are tested in distinct high-resolution simulations with interplanetary magnetic field (IMF) clock angles ranging from 30 to 165 degrees in global magnetohydrodynamic simulations using the three-dimensional Block-Adaptive Tree Solarwind Roe-type Upwind Scheme (BATS-R-US) code with a uniform resistivity, although the described techniques can be generally applied to any self-consistent magnetosphere code. Additional simulations are carried out to test location model dependence on IMF strength and dipole tilt. We find that most of the models match large portions of the magnetic separators wh...

  2. Comparing Sediment Yield Predictions from Different Hydrologic Modeling Schemes

    Science.gov (United States)

    Dahl, T. A.; Kendall, A. D.; Hyndman, D. W.

    2015-12-01

    Sediment yield, or the delivery of sediment from the landscape to a river, is a difficult process to accurately model. It is primarily a function of hydrology and climate, but influenced by landcover and the underlying soils. These additional factors make it much more difficult to accurately model than water flow alone. It is not intuitive what impact different hydrologic modeling schemes may have on the prediction of sediment yield. Here, two implementations of the Modified Universal Soil Loss Equation (MUSLE) are compared to examine the effects of hydrologic model choice. Both the Soil and Water Assessment Tool (SWAT) and the Landscape Hydrology Model (LHM) utilize the MUSLE for calculating sediment yield. SWAT is a lumped parameter hydrologic model developed by the USDA, which is commonly used for predicting sediment yield. LHM is a fully distributed hydrologic model developed primarily for integrated surface and groundwater studies at the watershed to regional scale. SWAT and LHM models were developed and tested for two large, adjacent watersheds in the Great Lakes region; the Maumee River and the St. Joseph River. The models were run using a variety of single model and ensemble downscaled climate change scenarios from the Coupled Model Intercomparison Project 5 (CMIP5). The initial results of this comparison are discussed here.

  3. MHD models compared with Artemis observations at -60 Re

    Science.gov (United States)

    Gencturk Akay, Iklim; Sibeck, David; Angelopoulos, Vassilis; Kaymaz, Zerefsan; Kuznetsova, Maria

    2016-07-01

    The distant magnetotail has been one of the least studied magnetic regions of the Earth's magnetosphere compared to the other near Earth both dayside and nightside magnetospheric regions owing to the limited number of spacecraft observations. Since 2011, ARTEMIS spacecraft give an excellent opportunity to study the magnetotail at lunar distances in terms of data quality and parameter space. This also gives opportunities to improve the magnetotail models at -60 Re and encourages the modelling studies of the distant magnetotail. Using ARTEMIS data in distant magnetotail, we create magnetic field and plasma flow vector maps in different planes and separated with IMF orientation to understand the magnetotail dynamics at this distance. For this study, we use CCMC's Run-on-Request resources of the MHD models; specifically SWMF-BATS-R-US, OpenGGCM, and LFM and perform the similar analysis with the models. Our main purpose in this study is to measure the performance of the MHD models at -60 Re distant magnetotail by comparing the model results with Artemis observations. In the literature, such a comprehensive comparative study is lacking in the distant tail. Preliminary results show that in general all three models underestimate the magnetic field structure while overestimating the flow speed. In the cross-sectional view, LFM seems to produce the better agreement with the observations. A clear dipolar magnetic field structure is seen with dawn-dusk asymmetry in all models owing to slight positive IMF By but the effect was found to be exaggerated. All models show tailward flows at this distance of the magnetotail, most possibly owing to the magnetic reconnection at the near Earth tail distances. A detailed comparison of several tail characteristics from the models will be presented and discussions will be given with respect to the observations from Artemis at this distance.

  4. A comparative analysis of multi-output frontier models

    Institute of Scientific and Technical Information of China (English)

    Tao ZHANG; Eoghan GARVEY

    2008-01-01

    Recently, there have been more debates on the methods of measuring efficiency. The main objective of this paper is to make a sensitivity analysis for different frontier models and compare the results obtained from the different methods of estimating multi-output frontier for a specific application. The methods include stochastic distance function frontier, stochastic ray frontier,and data envelopment analysis. The stochastic frontier regressions with and without the inefficiency effects model are also com-pared and tested. The results indicate that there are significant correlations between the results obtained from the alternative estimation methods.

  5. Comparative Study of Activity of Different Agings of Aluminum Nanopowders

    Institute of Scientific and Technical Information of China (English)

    YAN Zheng-Xin; DENG Jun; WANF Ya-Min; LIU Wei

    2009-01-01

    The structure and activity of aluminum nanopowders with a 3nm oxide layer on their surface (3-nm-OLA) and 30 nm oxide layers on their surface (30-nm-OLA) are investigated comparably under the same normal incident shock wave intensity. Their corresponding reaction products are characterized by x-ray diffraction, high-resolution transmission electron microscopy and x-ray pbotoelectron spectroscopy. The spectrum of x-ray diffraction shows that there are different phases of alumina in their products, which evidences directly the different reactingtemperature in the shock tube. The x-ray photoelectron spectroscopy reveals that the oxide layer thickness is 30 nm on the product surface of 30-nm-OLA, while it is only 3nm on 3-nm-OLA. Images of transmissionelectron microscopy present additional evidence that the agglomeration mechanism is over sintering one in the containing-30-nm-OLA system, the reversed mechanism is observed in the containing-3-nm-OLA reaction system.

  6. Image based 3D city modeling : Comparative study

    Science.gov (United States)

    Singh, S. P.; Jain, K.; Mandla, V. R.

    2014-06-01

    3D city model is a digital representation of the Earth's surface and it's related objects such as building, tree, vegetation, and some manmade feature belonging to urban area. The demand of 3D city modeling is increasing rapidly for various engineering and non-engineering applications. Generally four main image based approaches were used for virtual 3D city models generation. In first approach, researchers were used Sketch based modeling, second method is Procedural grammar based modeling, third approach is Close range photogrammetry based modeling and fourth approach is mainly based on Computer Vision techniques. SketchUp, CityEngine, Photomodeler and Agisoft Photoscan are the main softwares to represent these approaches respectively. These softwares have different approaches & methods suitable for image based 3D city modeling. Literature study shows that till date, there is no complete such type of comparative study available to create complete 3D city model by using images. This paper gives a comparative assessment of these four image based 3D modeling approaches. This comparative study is mainly based on data acquisition methods, data processing techniques and output 3D model products. For this research work, study area is the campus of civil engineering department, Indian Institute of Technology, Roorkee (India). This 3D campus acts as a prototype for city. This study also explains various governing parameters, factors and work experiences. This research work also gives a brief introduction, strengths and weakness of these four image based techniques. Some personal comment is also given as what can do or what can't do from these softwares. At the last, this study shows; it concluded that, each and every software has some advantages and limitations. Choice of software depends on user requirements of 3D project. For normal visualization project, SketchUp software is a good option. For 3D documentation record, Photomodeler gives good result. For Large city

  7. Conceptualizations of Creativity: Comparing Theories and Models of Giftedness

    Science.gov (United States)

    Miller, Angie L.

    2012-01-01

    This article reviews seven different theories of giftedness that include creativity as a component, comparing and contrasting how each one conceptualizes creativity as a part of giftedness. The functions of creativity vary across the models, suggesting that while the field of gifted education often cites the importance of creativity, the…

  8. Conceptualizations of Creativity: Comparing Theories and Models of Giftedness

    Science.gov (United States)

    Miller, Angie L.

    2012-01-01

    This article reviews seven different theories of giftedness that include creativity as a component, comparing and contrasting how each one conceptualizes creativity as a part of giftedness. The functions of creativity vary across the models, suggesting that while the field of gifted education often cites the importance of creativity, the…

  9. Theoretical biology: Comparing models of species abundance - Brief Communications Arising

    NARCIS (Netherlands)

    Chave, J.; Alonso, D.; Etienne, R.S.

    2006-01-01

    Ecologists are struggling to explain how so many tropical tree species can coexist in tropical forests, and several empirical studies have demonstrated that negative density dependence is an important mechanism of tree-species coexistence1, 2. Volkov et al.3 compare a model incorporating negative de

  10. Comparing satellite SAR and wind farm wake models

    DEFF Research Database (Denmark)

    Hasager, Charlotte Bay; Vincent, P.; Husson, R.

    2015-01-01

    The aim of the paper is to present offshore wind farm wake observed from satellite Synthetic Aperture Radar (SAR) wind fields from RADARSAT-1/-2 and Envisat and to compare these wakes qualitatively to wind farm wake model results. From some satellite SAR wind maps very long wakes are observed. Th...

  11. Comparing modelling techniques for analysing urban pluvial flooding.

    Science.gov (United States)

    van Dijk, E; van der Meulen, J; Kluck, J; Straatman, J H M

    2014-01-01

    Short peak rainfall intensities cause sewer systems to overflow leading to flooding of streets and houses. Due to climate change and densification of urban areas, this is expected to occur more often in the future. Hence, next to their minor (i.e. sewer) system, municipalities have to analyse their major (i.e. surface) system in order to anticipate urban flooding during extreme rainfall. Urban flood modelling techniques are powerful tools in both public and internal communications and transparently support design processes. To provide more insight into the (im)possibilities of different urban flood modelling techniques, simulation results have been compared for an extreme rainfall event. The results show that, although modelling software is tending to evolve towards coupled one-dimensional (1D)-two-dimensional (2D) simulation models, surface flow models, using an accurate digital elevation model, prove to be an easy and fast alternative to identify vulnerable locations in hilly and flat areas. In areas at the transition between hilly and flat, however, coupled 1D-2D simulation models give better results since catchments of major and minor systems can differ strongly in these areas. During the decision making process, surface flow models can provide a first insight that can be complemented with complex simulation models for critical locations.

  12. Active Appearance Model Based Hand Gesture Recognition

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    This paper addresses the application of hand gesture recognition in monocular image sequences using Active Appearance Model (AAM). For this work, the proposed algorithm is conposed of constructing AAMs and fitting the models to the interest region. In training stage, according to the manual labeled feature points, the relative AAM is constructed and the corresponding average feature is obtained. In recognition stage, the interesting hand gesture region is firstly segmented by skin and movement cues.Secondly, the models are fitted to the image that includes the hand gesture, and the relative features are extracted.Thirdly, the classification is done by comparing the extracted features and average features. 30 different gestures of Chinese sign language are applied for testing the effectiveness of the method. The Experimental results are given indicating good performance of the algorithm.

  13. Comparative Effectiveness of After-School Programs to Increase Physical Activity

    Directory of Open Access Journals (Sweden)

    Sabina B. Gesell

    2013-01-01

    Full Text Available Background. We conducted a comparative effectiveness analysis to evaluate the difference in the amount of physical activity children engaged in when enrolled in a physical activity-enhanced after-school program based in a community recreation center versus a standard school-based after-school program. Methods. The study was a natural experiment with 54 elementary school children attending the community ASP and 37 attending the school-based ASP. Accelerometry was used to measure physical activity. Data were collected at baseline, 6 weeks, and 12 weeks, with 91% retention. Results. At baseline, 43% of the multiethnic sample was overweight/obese, and the mean age was 7.9 years (SD = 1.7. Linear latent growth models suggested that the average difference between the two groups of children at Week 12 was 14.7 percentage points in moderate-vigorous physical activity (P<.001. Cost analysis suggested that children attending traditional school-based ASPs—at an average cost of $17.67 per day—would need an additional daily investment of $1.59 per child for 12 weeks to increase their moderate-vigorous physical activity by a model-implied 14.7 percentage points. Conclusions. A low-cost, alternative after-school program featuring adult-led physical activities in a community recreation center was associated with increased physical activity compared to standard-of-care school-based after-school program.

  14. Comparative effectiveness of after-school programs to increase physical activity.

    Science.gov (United States)

    Gesell, Sabina B; Sommer, Evan C; Lambert, E Warren; Vides de Andrade, Ana Regina; Whitaker, Lauren; Davis, Lauren; Beech, Bettina M; Mitchell, Stephanie J; Arinze, Nkiruka; Neloms, Stevon; Ryan, Colleen K; Barkin, Shari L

    2013-01-01

    We conducted a comparative effectiveness analysis to evaluate the difference in the amount of physical activity children engaged in when enrolled in a physical activity-enhanced after-school program based in a community recreation center versus a standard school-based after-school program. The study was a natural experiment with 54 elementary school children attending the community ASP and 37 attending the school-based ASP. Accelerometry was used to measure physical activity. Data were collected at baseline, 6 weeks, and 12 weeks, with 91% retention. At baseline, 43% of the multiethnic sample was overweight/obese, and the mean age was 7.9 years (SD = 1.7). Linear latent growth models suggested that the average difference between the two groups of children at Week 12 was 14.7 percentage points in moderate-vigorous physical activity (P children attending traditional school-based ASPs-at an average cost of $17.67 per day-would need an additional daily investment of $1.59 per child for 12 weeks to increase their moderate-vigorous physical activity by a model-implied 14.7 percentage points. A low-cost, alternative after-school program featuring adult-led physical activities in a community recreation center was associated with increased physical activity compared to standard-of-care school-based after-school program.

  15. Comparative 3-D Modeling of tmRNA

    Directory of Open Access Journals (Sweden)

    Wower Iwona

    2005-06-01

    Full Text Available Abstract Background Trans-translation releases stalled ribosomes from truncated mRNAs and tags defective proteins for proteolytic degradation using transfer-messenger RNA (tmRNA. This small stable RNA represents a hybrid of tRNA- and mRNA-like domains connected by a variable number of pseudoknots. Comparative sequence analysis of tmRNAs found in bacteria, plastids, and mitochondria provides considerable insights into their secondary structures. Progress toward understanding the molecular mechanism of template switching, which constitutes an essential step in trans-translation, is hampered by our limited knowledge about the three-dimensional folding of tmRNA. Results To facilitate experimental testing of the molecular intricacies of trans-translation, which often require appropriately modified tmRNA derivatives, we developed a procedure for building three-dimensional models of tmRNA. Using comparative sequence analysis, phylogenetically-supported 2-D structures were obtained to serve as input for the program ERNA-3D. Motifs containing loops and turns were extracted from the known structures of other RNAs and used to improve the tmRNA models. Biologically feasible 3-D models for the entire tmRNA molecule could be obtained. The models were characterized by a functionally significant close proximity between the tRNA-like domain and the resume codon. Potential conformational changes which might lead to a more open structure of tmRNA upon binding to the ribosome are discussed. The method, described in detail for the tmRNAs of Escherichia coli, Bacillus anthracis, and Caulobacter crescentus, is applicable to every tmRNA. Conclusion Improved molecular models of biological significance were obtained. These models will guide in the design of experiments and provide a better understanding of trans-translation. The comparative procedure described here for tmRNA is easily adopted for the modeling the members of other RNA families.

  16. Comparative analysis of used car price evaluation models

    Science.gov (United States)

    Chen, Chuancan; Hao, Lulu; Xu, Cong

    2017-05-01

    An accurate used car price evaluation is a catalyst for the healthy development of used car market. Data mining has been applied to predict used car price in several articles. However, little is studied on the comparison of using different algorithms in used car price estimation. This paper collects more than 100,000 used car dealing records throughout China to do empirical analysis on a thorough comparison of two algorithms: linear regression and random forest. These two algorithms are used to predict used car price in three different models: model for a certain car make, model for a certain car series and universal model. Results show that random forest has a stable but not ideal effect in price evaluation model for a certain car make, but it shows great advantage in the universal model compared with linear regression. This indicates that random forest is an optimal algorithm when handling complex models with a large number of variables and samples, yet it shows no obvious advantage when coping with simple models with less variables.

  17. A microbial model of economic trading and comparative advantage.

    Science.gov (United States)

    Enyeart, Peter J; Simpson, Zachary B; Ellington, Andrew D

    2015-01-07

    The economic theory of comparative advantage postulates that beneficial trading relationships can be arrived at by two self-interested entities producing the same goods as long as they have opposing relative efficiencies in producing those goods. The theory predicts that upon entering trade, in order to maximize consumption both entities will specialize in producing the good they can produce at higher efficiency, that the weaker entity will specialize more completely than the stronger entity, and that both will be able to consume more goods as a result of trade than either would be able to alone. We extend this theory to the realm of unicellular organisms by developing mathematical models of genetic circuits that allow trading of a common good (specifically, signaling molecules) required for growth in bacteria in order to demonstrate comparative advantage interactions. In Conception 1, the experimenter controls production rates via exogenous inducers, allowing exploration of the parameter space of specialization. In Conception 2, the circuits self-regulate via feedback mechanisms. Our models indicate that these genetic circuits can demonstrate comparative advantage, and that cooperation in such a manner is particularly favored under stringent external conditions and when the cost of production is not overly high. Further work could involve implementing the models in living bacteria and searching for naturally occurring cooperative relationships between bacteria that conform to the principles of comparative advantage.

  18. Comparative Analysis of Visco-elastic Models with Variable Parameters

    Directory of Open Access Journals (Sweden)

    Silviu Nastac

    2010-01-01

    Full Text Available The paper presents a theoretical comparative study for computational behaviour analysis of vibration isolation elements based on viscous and elastic models with variable parameters. The changing of elastic and viscous parameters can be produced by natural timed evolution demo-tion or by heating developed into the elements during their working cycle. It was supposed both linear and non-linear numerical viscous and elastic models, and their combinations. The results show the impor-tance of numerical model tuning with the real behaviour, as such the characteristics linearity, and the essential parameters for damping and rigidity. Multiple comparisons between linear and non-linear simulation cases dignify the basis of numerical model optimization regarding mathematical complexity vs. results reliability.

  19. How Do Sociodemographics and Activity Participations Affect Activity-Travel? Comparative Study between Women and Men

    Directory of Open Access Journals (Sweden)

    Min Yang

    2014-01-01

    Full Text Available Activity-travel behaviors of women and men are different because they have different social and household responsibilities. However, studies concerning gender differences are mainly limited in developed countries. This paper concentrates on gender role-based differences in activity-travel behavior in a typical developing country, namely, China. Using data from 3656 cases collected through surveys conducted in Shangyu, data processing, method choice, and descriptive analysis were conducted. Binary and ordered logistic regression models segmented by gender were developed to evaluate the mechanism through which individual sociodemographics, household characteristics, and activity participations affect the number of trip chain types and activities for women and men. The results show that women aged 30 to 50 perform less subsistence activities. However, the difference between the different age groups of men is not as significant. In addition, men with bicycles and electric bicycles have more subsistence and maintenance activities, whereas women do not have these attributes. Moreover, women with children under schooling age make more maintenance trip chains but less leisure trip chains and activities, whereas men are free from this influence. Furthermore, both women and men perform more subsistence activities if the duration increases, and men have less influences than women do.

  20. [Comparative antivitamin activity of oxythiamine disulfide and its monosulfoxide].

    Science.gov (United States)

    Zimatkina, T I; Oparin, D A

    1990-01-01

    The B1-antivitamin activity of oxythiamine disulphide monosulphoxide has been determined in experiments on albino mice. It is shown that this derivative is less toxic and exerts a more profound and prolonged inhibitory action on the pyruvate dehydrogenase and transketolase activity in the animal body in comparison with initial oxythiamine disulphide.

  1. Modeling Error in Quantitative Macro-Comparative Research

    Directory of Open Access Journals (Sweden)

    Salvatore J. Babones

    2015-08-01

    Full Text Available Much quantitative macro-comparative research (QMCR relies on a common set of published data sources to answer similar research questions using a limited number of statistical tools. Since all researchers have access to much the same data, one might expect quick convergence of opinion on most topics. In reality, of course, differences of opinion abound and persist. Many of these differences can be traced, implicitly or explicitly, to the different ways researchers choose to model error in their analyses. Much careful attention has been paid in the political science literature to the error structures characteristic of time series cross-sectional (TSCE data, but much less attention has been paid to the modeling of error in broadly cross-national research involving large panels of countries observed at limited numbers of time points. Here, and especially in the sociology literature, multilevel modeling has become a hegemonic – but often poorly understood – research tool. I argue that widely-used types of multilevel models, commonly known as fixed effects models (FEMs and random effects models (REMs, can produce wildly spurious results when applied to trended data due to mis-specification of error. I suggest that in most commonly-encountered scenarios, difference models are more appropriate for use in QMC.

  2. Comparative assessment of PV plant performance models considering climate effects

    DEFF Research Database (Denmark)

    Tina, Giuseppe; Ventura, Cristina; Sera, Dezso

    2017-01-01

    The paper investigates the effect of climate conditions on the accuracy of PV system performance models (physical and interpolation methods) which are used within a monitoring system as a reference for the power produced by a PV system to detect inefficient or faulty operating conditions....... The methodological approach is based on comparative tests of the analyzed models applied to two PV plants installed respectively in north of Denmark (Aalborg) and in the south of Italy (Agrigento). The different ambient, operating and installation conditions allow to understand how these factors impact the precision...... and effectiveness of such approaches, among these factors it is worth mentioning the different percentage of diffuse component of the yearly solar radiation on the global one. The experimental results show the effectiveness of the proposed approach. In order to have the possibility to analyze and compare...

  3. Comparative activity of some veterinary pharmaceutical products in swine dysentery

    Directory of Open Access Journals (Sweden)

    Cristina, T. Romeo

    2010-12-01

    Full Text Available One of the diseases that cause great damage in the pig breeding farms, Brachyspyra swine dysentery has a special importance because involve great losses both by growth failure and high mortality andsignificant costs to the prevention and control. The study was conducted in a swine farm in Timis County, where the disease was originally identified in autumn of year 2009. Cumulative adverse conditions have affected the rate of morbidity and mortality. Themost common clinical developments in the unit were usually acute and subacute. Research included: a comparative study of the effectiveness of tiamulin fumarate, hydrogenated and dimetridazole powder in sick acute and subacute forms in piglets, at the weaning period; the comparative study of efficiency in therapy of soluble tiamulin (the tiamulin fumarate-hydrogenated and of the injection of piglets effective and the study of growth indicators: average daily gain.Experiment IGroup I consisted in 15 piglets with an average weight per lot of 7.60 kg/head (batch weight: 114kg received p.o. dimetridazole insoluble powder (Romvac Bucharest, mixed in feed, for 5 days dose of 25 mg/kg.bw. During the observation, two mortalities were recorded, representing 13.33% of the treated lot. Other animals from the group were clinically cured, the signs of the disease gradually disappeared, and the temperature returned to normal enteric symptoms. The observation period after the 21 days of experiment, the batchweight was 114.2 kg, corresponding to growth registered 95.5 g/head/day.Group II, of 15 pigs with enteritis clinical signs, have had an average weight per lot of 7.48 kg/head, and he has undergone treatment with tiamulin product (Novartis Animal Health soluble granules, in drinking water. Treatments were performed for 5 consecutive days at a dose of 60 mg/liter of drinking water. In this group, diarrhea symptoms decreased and general status of the animals gradually improved, no mortality was recorded five days

  4. A Statistical Word-Level Translation Model for Comparable Corpora

    Science.gov (United States)

    2000-06-01

    readily available resources such as corpora, thesauri, bilingual and multilingual lexicons and dictionaries. The acquisition of such resources has...could aid in Monolingual Information Retrieval (MIR) by methods of query expansion, and thesauri construction. To date, most of the existing...testing the limits of its performance. Future directions include testing the model with a monolingual comparable corpus, e.g. WSJ [42M] and either IACA/B

  5. Comparative study of hemolytic activity of Bordetella species

    Directory of Open Access Journals (Sweden)

    C N Khobragade

    2009-11-01

    Full Text Available Background and objectives: Bordetella species colonize the respiratory tract of mammals and thereby cause the whooping cough. Most of the species produce adenylate cyclase - a toxin ( hemolysin responsible for increasing intracellular cyclic AMP (cAMP levels in mammalian neutrophils and macrophages and as a consequence their phagocytic function get impaired . This study was carried out to isolate species of Bordetella and to study the hemolytic activity of each species on RBCs of sheep, human and poultry at varied culture conditions by altering the temperature, pH and cell age."nMaterials and Methods: Three pathogenic Bordetella species were isolated from fifty suspected whooping cough patients on Bordet-Gengou agar and identified by their biochemical profiles. The hemolytic activity of B. pertussis, B. parapertussis and B. bronchiseptica was investigated in terms of cell bound and cell free hemolysin on human, poultry and sheep RBCs at variable pH, temperature and cell age in Stainer Scholt broth. The hemolysin activity was also determined qualitatively on blood agar containing different blood samples."nResults: All the species revealed optimum hemolytic activity in pH range 7.5-8.0 (in slight alkaline condition, temperature 37°C and cell age up to 20-24 hrs. The cell bound hemolytic activity was found to be maximum than cell free activity and varied with blood samples of different species. B. pertussis showed maximum hemolytic activity on human red blood cells followed by poultry and sheep RBCs. B. parapertussis and B. bronchiseptica showed maximum hemolytic activity on sheep and poultry RBCs respectively."nConclusion: The findings of our study revealed that different determinants are involved in host interactions and virulence of Bordetella species.

  6. A new thermal comfort approach comparing adaptive and PMV models

    Energy Technology Data Exchange (ETDEWEB)

    Orosa, Jose A. [Universidade da Coruna, Departamento de Energia y P. M. Paseo de Ronda, n :51, 15011. A Coruna (Spain); Oliveira, Armando C. [Universidade do Porto, Faculdade de Engenharia, New Energy Tec. Unit. Rua Dr Roberto Frias, 4200-465 Porto (Portugal)

    2011-03-15

    In buildings with heating, ventilation, and air-conditioning (HVAC), the Predicted Mean Vote index (PMV) was successful at predicting comfort conditions, whereas in naturally ventilated buildings, only adaptive models provide accurate predictions. On the other hand, permeable coverings can be considered as a passive control method of indoor conditions and, consequently, have implications in the perception of indoor air quality, local thermal comfort, and energy savings. These energy savings were measured in terms of the set point temperature established in accordance with adaptive methods. Problems appear when the adaptive model suggests the same neutral temperature for ambiences with the same indoor temperature but different relative humidities. In this paper, a new design of the PMV model is described to compare the neutral temperature to real indoor conditions. Results showed that this new PMV model tends to overestimate thermal neutralities but with a lower value than Fanger's PMV index. On the other hand, this new PMV model considers indoor relative humidity, showing a clear differentiation of indoor ambiences in terms of it, unlike adaptive models. Finally, spaces with permeable coverings present indoor conditions closer to thermal neutrality, with corresponding energy savings. (author)

  7. Comparing the ecological relevance of four wave exposure models

    Science.gov (United States)

    Sundblad, G.; Bekkby, T.; Isæus, M.; Nikolopoulos, A.; Norderhaug, K. M.; Rinde, E.

    2014-03-01

    Wave exposure is one of the main structuring forces in the marine environment. Methods that enable large scale quantification of environmental variables have become increasingly important for predicting marine communities in the context of spatial planning and coastal zone management. Existing methods range from cartographic solutions to numerical hydrodynamic simulations, and differ in the scale and spatial coverage of their outputs. Using a biological exposure index we compared the performance of four wave exposure models ranging from simple to more advanced techniques. All models were found to be related to the biological exposure index and their performance, measured as bootstrapped R2 distributions, overlapped. Qualitatively, there were differences in the spatial patterns indicating higher complexity with more advanced techniques. In order to create complex spatial patterns wave exposure models should include diffraction, especially in coastal areas rich in islands. The inclusion of wind strength and frequency, in addition to wind direction and bathymetry, further tended to increase the amount of explained variation. The large potential of high-resolution numerical models to explain the observed patterns of species distribution in complex coastal areas provide exciting opportunities for future research. Easy access to relevant wave exposure models will aid large scale habitat classification systems and the continuously growing field of marine species distribution modelling, ultimately serving marine spatial management and planning.

  8. Comparing Two Strategies to Model Uncertainties in Structural Dynamics

    Directory of Open Access Journals (Sweden)

    Rubens Sampaio

    2010-01-01

    Full Text Available In the modeling of dynamical systems, uncertainties are present and they must be taken into account to improve the prediction of the models. Some strategies have been used to model uncertainties and the aim of this work is to discuss two of those strategies and to compare them. This will be done using the simplest model possible: a two d.o.f. (degrees of freedom dynamical system. A simple system is used because it is very helpful to assure a better understanding and, consequently, comparison of the strategies. The first strategy (called parametric strategy consists in taking each spring stiffness as uncertain and a random variable is associated to each one of them. The second strategy (called nonparametric strategy is more general and considers the whole stiffness matrix as uncertain, and associates a random matrix to it. In both cases, the probability density functions either of the random parameters or of the random matrix are deduced from the Maximum Entropy Principle using only the available information. With this example, some important results can be discussed, which cannot be assessed when complex structures are used, as it has been done so far in the literature. One important element for the comparison of the two strategies is the analysis of the samples spaces and the how to compare them.

  9. Comparing Supply-Side Specifications in Models of Global Agriculture and the Food System

    Energy Technology Data Exchange (ETDEWEB)

    Robinson, Sherman; van Meijl, Hans; Willenbockel, Dirk; Valin, Hugo; Fujimori, Shinichiro; Masui, Toshihiko; Sands, Ronald; Wise, Marshall A.; Calvin, Katherine V.; Havlik, Petr; Mason d' Croz, Daniel; Tabeau, Andrzej; Kavallari, Aikaterini; Schmitz, Christoph; Dietrich, Jan P.; von Lampe, Martin

    2014-01-01

    This paper compares the theoretical specification of production and technical change across the partial equilibrium (PE) and computable general equilibrium (CGE) models of the global agricultural and food system included in the AgMIP model comparison study. The two modeling approaches have different theoretical underpinnings concerning the scope of economic activity they capture and how they represent technology and the behavior of supply and demand in markets. This paper focuses on their different specifications of technology and supply behavior, comparing their theoretical and empirical treatments. While the models differ widely in their specifications of technology, both within and between the PE and CGE classes of models, we find that the theoretical responsiveness of supply to changes in prices can be similar, depending on parameter choices that define the behavior of supply functions over the domain of applicability defined by the common scenarios used in the AgMIP comparisons. In particular, we compare the theoretical specification of supply in CGE models with neoclassical production functions and PE models that focus on land and crop yields in agriculture. In practice, however, comparability of results given parameter choices is an empirical question, and the models differ in their sensitivity to variations in specification. To illustrate the issues, sensitivity analysis is done with one global CGE model, MAGNET, to indicate how the results vary with different specification of technical change, and how they compare with the results from PE models.

  10. Comparative assessment of antioxidant activity of chicory products

    Directory of Open Access Journals (Sweden)

    Z. A. Badretdinova

    2016-01-01

    Full Text Available There are various methods for determining the antioxidant activity. They are differing by the source of oxidation, oxidized compounds and methods for the measurement of oxidized compounds. Methods for determination of antioxidant activity provide a wide range of results, so the evaluation of the antioxidant activity should be carried out in several ways, and the results should be interpreted with caution. In assessing antioxidant capacity is necessary to consider not only the nature and content of the reducing agent in the test facility, but also the possibility of their mutual influence. The objects of research in this research work were Instant chicory (Leroux, Fried chicory (Leroux, Instant chicory (LLC Favorit, Instant chicory (LLC SlavKofe, Instant chicory with hawthorn (Iceberg Ltd and K, Instant chicory (LLC Flagistom, Instant chicory (Ltd. Around the World, Instant chicory (LLC Beta +, Chicory flour (Leroux, Chicory flour. Antioxidant activity of the products of chicory determined by spectrophotometric (using adrenaline and 2,2 – diphenyl- 1-picrylhydrazyl, and amperometric methods. These results indicate that chicory products possess antioxidant activity but not give fully correlated with each other results. The highest antioxidant activity have fried products from chicory – Instant chicory (LLC SlavKofe and Instant chicory with hawthorn (Iceberg Ltd and K. No fried products from chicory (Chicory flour (Leroux have lower antioxidant activity then fried products from chicory. Because during frying new compounds are formed – chikoreol, which comprises acetic and valeric acid, acrolein and furfural, furfuryl alcohol, diacetyl. Best convergence results provide spectrophotometric methods using epinephrine and 2,2 – diphenyl-1-picrylhydrazyl.

  11. Comparative studies on the anti-inflammatory and analgesic activity ...

    African Journals Online (AJOL)

    USER

    2010-05-17

    May 17, 2010 ... fresh and boiled extracts of the berries in animal models in view of ... for each experiment. Animals. Male rats (Rattus norvegicus) of Wistar strains weighing between. 120 and ..... Africa Natural History Society, Nairobi. Balkwill ...

  12. Saccharomyces cerevisiae as a model organism: a comparative study.

    Directory of Open Access Journals (Sweden)

    Hiren Karathia

    Full Text Available BACKGROUND: Model organisms are used for research because they provide a framework on which to develop and optimize methods that facilitate and standardize analysis. Such organisms should be representative of the living beings for which they are to serve as proxy. However, in practice, a model organism is often selected ad hoc, and without considering its representativeness, because a systematic and rational method to include this consideration in the selection process is still lacking. METHODOLOGY/PRINCIPAL FINDINGS: In this work we propose such a method and apply it in a pilot study of strengths and limitations of Saccharomyces cerevisiae as a model organism. The method relies on the functional classification of proteins into different biological pathways and processes and on full proteome comparisons between the putative model organism and other organisms for which we would like to extrapolate results. Here we compare S. cerevisiae to 704 other organisms from various phyla. For each organism, our results identify the pathways and processes for which S. cerevisiae is predicted to be a good model to extrapolate from. We find that animals in general and Homo sapiens in particular are some of the non-fungal organisms for which S. cerevisiae is likely to be a good model in which to study a significant fraction of common biological processes. We validate our approach by correctly predicting which organisms are phenotypically more distant from S. cerevisiae with respect to several different biological processes. CONCLUSIONS/SIGNIFICANCE: The method we propose could be used to choose appropriate substitute model organisms for the study of biological processes in other species that are harder to study. For example, one could identify appropriate models to study either pathologies in humans or specific biological processes in species with a long development time, such as plants.

  13. Extraction DNA from Activated Sludge-Comparing with Soil Sample

    Institute of Scientific and Technical Information of China (English)

    谢冰; 奚旦立; 陈季华

    2003-01-01

    DNA directly extraction from activated sludge and soil sample with enzyme lyses methods was investigated in this paper. DNA yield from activated sludge was 3.0 mg/g. VLSS, and 28.2-43.8 μg/g soil respectively. The resulting DNA is suitable for PCR.By studied methods, higher quality and quantity of sludge DNA could be obtained rapidly and inexpensively from large number of samples, and the PCR product obtained from this protocol was not affected by contaminated higher concentration of heavy metals.

  14. Comparative Activities of Cattle and Swine Platelet Microbicidal Proteins.

    Science.gov (United States)

    Ivanov, Iuri B; Gritsenko, Viktor A

    2009-12-01

    The bactericidal activities of cattle and swine platelet microbicidal proteins (PMPs) with their comparison with human PMP were studied. Activities of PMP were tested against Bacillus subtilis, Bacillus cereus, Staphylococcus aureus, Staphylococcus epidermidis, Micrococcus lysodeikticus and Escherichia coli. B. subtilis and B. cereus were high susceptible to PMP at very low concentrations. Of the gram-positive cocci studied, M. lysodeikticus and S. aureus were the most, and S. epidermidis the least, susceptible. E. coli was found to be relatively resistant to the lethal action of all PMP. The findings of this study confirm that the existence of antimicrobial peptides is conserved among mammalian platelets.

  15. Building v/s Exploring Models: Comparing Learning of Evolutionary Processes through Agent-based Modeling

    Science.gov (United States)

    Wagh, Aditi

    modalities, with students who built models not incorporating slippage explanations in responses. Study 3 compares these modalities with a control using traditional activities. Pre and posttests reveal that the two modalities manifested greater facility with accessing and assembling rules than the control. The dissertation offers implications for the design of learning environments for evolutionary change, design of the two modalities based on their strengths and weaknesses, and teacher training for the same.

  16. Dinucleotide controlled null models for comparative RNA gene prediction

    Directory of Open Access Journals (Sweden)

    Gesell Tanja

    2008-05-01

    Full Text Available Abstract Background Comparative prediction of RNA structures can be used to identify functional noncoding RNAs in genomic screens. It was shown recently by Babak et al. [BMC Bioinformatics. 8:33] that RNA gene prediction programs can be biased by the genomic dinucleotide content, in particular those programs using a thermodynamic folding model including stacking energies. As a consequence, there is need for dinucleotide-preserving control strategies to assess the significance of such predictions. While there have been randomization algorithms for single sequences for many years, the problem has remained challenging for multiple alignments and there is currently no algorithm available. Results We present a program called SISSIz that simulates multiple alignments of a given average dinucleotide content. Meeting additional requirements of an accurate null model, the randomized alignments are on average of the same sequence diversity and preserve local conservation and gap patterns. We make use of a phylogenetic substitution model that includes overlapping dependencies and site-specific rates. Using fast heuristics and a distance based approach, a tree is estimated under this model which is used to guide the simulations. The new algorithm is tested on vertebrate genomic alignments and the effect on RNA structure predictions is studied. In addition, we directly combined the new null model with the RNAalifold consensus folding algorithm giving a new variant of a thermodynamic structure based RNA gene finding program that is not biased by the dinucleotide content. Conclusion SISSIz implements an efficient algorithm to randomize multiple alignments preserving dinucleotide content. It can be used to get more accurate estimates of false positive rates of existing programs, to produce negative controls for the training of machine learning based programs, or as standalone RNA gene finding program. Other applications in comparative genomics that require

  17. Comparative Modelling of the Spectra of Cool Giants

    Science.gov (United States)

    Lebzelter, T.; Heiter, U.; Abia, C.; Eriksson, K.; Ireland, M.; Neilson, H.; Nowotny, W; Maldonado, J; Merle, T.; Peterson, R.; hide

    2012-01-01

    Our ability to extract information from the spectra of stars depends on reliable models of stellar atmospheres and appropriate techniques for spectral synthesis. Various model codes and strategies for the analysis of stellar spectra are available today. Aims. We aim to compare the results of deriving stellar parameters using different atmosphere models and different analysis strategies. The focus is set on high-resolution spectroscopy of cool giant stars. Methods. Spectra representing four cool giant stars were made available to various groups and individuals working in the area of spectral synthesis, asking them to derive stellar parameters from the data provided. The results were discussed at a workshop in Vienna in 2010. Most of the major codes currently used in the astronomical community for analyses of stellar spectra were included in this experiment. Results. We present the results from the different groups, as well as an additional experiment comparing the synthetic spectra produced by various codes for a given set of stellar parameters. Similarities and differences of the results are discussed. Conclusions. Several valid approaches to analyze a given spectrum of a star result in quite a wide range of solutions. The main causes for the differences in parameters derived by different groups seem to lie in the physical input data and in the details of the analysis method. This clearly shows how far from a definitive abundance analysis we still are.

  18. A New Method of Comparing Forcing Agents in Climate Models

    Energy Technology Data Exchange (ETDEWEB)

    Kravitz, Benjamin S.; MacMartin, Douglas; Rasch, Philip J.; Jarvis, Andrew

    2015-10-14

    We describe a new method of comparing different climate forcing agents (e.g., CO2, CH4, and solar irradiance) that avoids many of the ambiguities introduced by temperature-related climate feedbacks. This is achieved by introducing an explicit feedback loop external to the climate model that adjusts one forcing agent to balance another while keeping global mean surface temperature constant. Compared to current approaches, this method has two main advantages: (i) the need to define radiative forcing is bypassed and (ii) by maintaining roughly constant global mean temperature, the effects of state dependence on internal feedback strengths are minimized. We demonstrate this approach for several different forcing agents and derive the relationships between these forcing agents in two climate models; comparisons between forcing agents are highly linear in concordance with predicted functional forms. Transitivity of the relationships between the forcing agents appears to hold within a wide range of forcing. The relationships between the forcing agents obtained from this method are consistent across both models but differ from relationships that would be obtained from calculations of radiative forcing, highlighting the importance of controlling for surface temperature feedback effects when separating radiative forcing and climate response.

  19. Ionospheric topside models compared with experimental electron density profiles

    Directory of Open Access Journals (Sweden)

    S. M. Radicella

    2005-06-01

    Full Text Available Recently an increasing number of topside electron density profiles has been made available to the scientific community on the Internet. These data are important for ionospheric modeling purposes, since the experimental information on the electron density above the ionosphere maximum of ionization is very scarce. The present work compares NeQuick and IRI models with the topside electron density profiles available in the databases of the ISIS2, IK19 and Cosmos 1809 satellites. Experimental electron content from the F2 peak up to satellite height and electron densities at fixed heights above the peak have been compared under a wide range of different conditions. The analysis performed points out the behavior of the models and the improvements needed to be assessed to have a better reproduction of the experimental results. NeQuick topside is a modified Epstein layer, with thickness parameter determined by an empirical relation. It appears that its performance is strongly affected by this parameter, indicating the need for improvements of its formulation. IRI topside is based on Booker's approach to consider two parts with constant height gradients. It appears that this formulation leads to an overestimation of the electron density in the upper part of the profiles, and overestimation of TEC.

  20. A comparative structure-function analysis of active-site inhibitors of Vibrio cholerae cholix toxin.

    Science.gov (United States)

    Lugo, Miguel R; Merrill, A Rod

    2015-09-01

    Cholix toxin from Vibrio cholerae is a novel mono-ADP-ribosyltransferase (mART) toxin that shares structural and functional properties with Pseudomonas aeruginosa exotoxin A and Corynebacterium diphtheriae diphtheria toxin. Herein, we have used the high-resolution X-ray structure of full-length cholix toxin in the apo form, NAD(+) bound, and 10 structures of the cholix catalytic domain (C-domain) complexed with several strong inhibitors of toxin enzyme activity (NAP, PJ34, and the P-series) to study the binding mode of the ligands. A pharmacophore model based on the active pose of NAD(+) was compared with the active conformation of the inhibitors, which revealed a cationic feature in the side chain of the inhibitors that may determine the active pose. Moreover, a conformational search was conducted for the missing coordinates of one of the main active-site loops (R-loop). The resulting structural models were used to evaluate the interaction energies and for 3D-QSAR modeling. Implications for a rational drug design approach for mART toxins were derived.

  1. COGNITIVE COMPETENCE COMPARED TO COGNITIVE INDEPENDENCE AND COGNITIVE ACTIVITY

    Directory of Open Access Journals (Sweden)

    Irina B. Shmigirilova

    2014-01-01

    Full Text Available The research is aimed at identifying the essence of the cognitive competence concept in comparison with the concepts of cognitive independence and activity.Methods: The methodology implies a theoretical analysis of psychopedagogical and methodological materials on the cognitive competence formation; generalized teaching experience; empirical methods of direct observations of educational process in the secondary school classrooms; interviews with school teachers and pupils.Results: The research outcomes reveal a semantic intersection between the cognitive competence, independence and activity, and their distinctive features. The paper emphasizes the importance of cognitive competence as an adaptive mechanism in situations of uncertainty and instability.Scientific novelty: The author clarifies the concept of cognitive competence regarding it as a multi-component and systematic characteristic of a personality.Practical significance: The research findings can be used by specialists in didactics developing the teaching techniques of cognitive competence formation for schoolchildren.

  2. COGNITIVE COMPETENCE COMPARED TO COGNITIVE INDEPENDENCE AND COGNITIVE ACTIVITY

    OpenAIRE

    2014-01-01

    The research is aimed at identifying the essence of the cognitive competence concept in comparison with the concepts of cognitive independence and activity.Methods: The methodology implies a theoretical analysis of psychopedagogical and methodological materials on the cognitive competence formation; generalized teaching experience; empirical methods of direct observations of educational process in the secondary school classrooms; interviews with school teachers and pupils.Results: The researc...

  3. Comparative efficacy of switching to natalizumab in active multiple sclerosis

    DEFF Research Database (Denmark)

    Spelman, Timothy; Kalincik, Tomas; Zhang, Annie

    2015-01-01

    included were registered in MSBase or the TYSABRI Observational Program (TOP), had relapsed on IFNβ or GA within 12 months prior to switching to another therapy, and had initiated natalizumab or IFNβ/GA treatment ≤6 months after discontinuing prior therapy. Covariates were balanced across post switch...... treatment groups by propensity score matching at treatment initiation. Relapse, persistence, and disability measures were compared between matched treatment arms in the total population (n = 869/group) and in subgroups defined by prior treatment history (IFNβ only [n = 578/group], GA only [n = 165/group......], or both IFNβ and GA [n = 176/group]). RESULTS: Compared to switching between IFNβ and GA, switching to natalizumab reduced annualized relapse rate in year one by 65-75%, the risk of first relapse by 53-82% (mean follow-up 1.7-2.2 years) and treatment discontinuation events by 48-65% (all P ≤ 0...

  4. Comparative bioenergetics modeling of two Lake Trout morphotypes

    Science.gov (United States)

    Kepler, Megan V.; Wagner, Tyler; Sweka, John A.

    2014-01-01

    Efforts to restore Lake Trout Salvelinus namaycush in the Laurentian Great Lakes have been hampered for decades by several factors, including overfishing and invasive species (e.g., parasitism by Sea Lampreys Petromyzon marinus and reproductive deficiencies associated with consumption of Alewives Alosa pseudoharengus). Restoration efforts are complicated by the presence of multiple body forms (i.e., morphotypes) of Lake Trout that differ in habitat utilization, prey consumption, lipid storage, and spawning preferences. Bioenergetics models constitute one tool that is used to help inform management and restoration decisions; however, bioenergetic differences among morphotypes have not been evaluated. The goal of this research was to investigate bioenergetic differences between two actively stocked morphotypes: lean and humper Lake Trout. We measured consumption and respiration rates across a wide range of temperatures (4–22°C) and size-classes (5–100 g) to develop bioenergetics models for juvenile Lake Trout. Bayesian estimation was used so that uncertainty could be propagated through final growth predictions. Differences between morphotypes were minimal, but when present, the differences were temperature and weight dependent. Basal respiration did not differ between morphotypes at any temperature or size-class. When growth and consumption differed between morphotypes, the differences were not consistent across the size ranges tested. Management scenarios utilizing the temperatures presently found in the Great Lakes (e.g., predicted growth at an average temperature of 11.7°C and 14.4°C during a 30-d period) demonstrated no difference in growth between the two morphotypes. Due to a lack of consistent differences between lean and humper Lake Trout, we developed a model that combined data from both morphotypes. The combined model yielded results similar to those of the morphotype-specific models, suggesting that accounting for morphotype differences may

  5. MEG source localization of spatially extended generators of epileptic activity: comparing entropic and hierarchical bayesian approaches.

    Directory of Open Access Journals (Sweden)

    Rasheda Arman Chowdhury

    Full Text Available Localizing the generators of epileptic activity in the brain using Electro-EncephaloGraphy (EEG or Magneto-EncephaloGraphy (MEG signals is of particular interest during the pre-surgical investigation of epilepsy. Epileptic discharges can be detectable from background brain activity, provided they are associated with spatially extended generators. Using realistic simulations of epileptic activity, this study evaluates the ability of distributed source localization methods to accurately estimate the location of the generators and their sensitivity to the spatial extent of such generators when using MEG data. Source localization methods based on two types of realistic models have been investigated: (i brain activity may be modeled using cortical parcels and (ii brain activity is assumed to be locally smooth within each parcel. A Data Driven Parcellization (DDP method was used to segment the cortical surface into non-overlapping parcels and diffusion-based spatial priors were used to model local spatial smoothness within parcels. These models were implemented within the Maximum Entropy on the Mean (MEM and the Hierarchical Bayesian (HB source localization frameworks. We proposed new methods in this context and compared them with other standard ones using Monte Carlo simulations of realistic MEG data involving sources of several spatial extents and depths. Detection accuracy of each method was quantified using Receiver Operating Characteristic (ROC analysis and localization error metrics. Our results showed that methods implemented within the MEM framework were sensitive to all spatial extents of the sources ranging from 3 cm(2 to 30 cm(2, whatever were the number and size of the parcels defining the model. To reach a similar level of accuracy within the HB framework, a model using parcels larger than the size of the sources should be considered.

  6. Comparative dynamic analysis of the full Grossman model.

    Science.gov (United States)

    Ried, W

    1998-08-01

    The paper applies the method of comparative dynamic analysis to the full Grossman model. For a particular class of solutions, it derives the equations implicitly defining the complete trajectories of the endogenous variables. Relying on the concept of Frisch decision functions, the impact of any parametric change on an endogenous variable can be decomposed into a direct and an indirect effect. The focus of the paper is on marginal changes in the rate of health capital depreciation. It also analyses the impact of either initial financial wealth or the initial stock of health capital. While the direction of most effects remains ambiguous in the full model, the assumption of a zero consumption benefit of health is sufficient to obtain a definite for any direct or indirect effect.

  7. Comparing theoretical models of our galaxy with observations

    Directory of Open Access Journals (Sweden)

    Johnston K.V.

    2012-02-01

    Full Text Available With the advent of large scale observational surveys to map out the stars in our galaxy, there is a need for an efficient tool to compare theoretical models of our galaxy with observations. To this end, we describe here the code Galaxia, which uses efficient and fast algorithms for creating a synthetic survey of the Milky Way, and discuss its uses. Given one or more observational constraints like the color-magnitude bounds, a survey size and geometry, Galaxia returns a catalog of stars in accordance with a given theoretical model of the Milky Way. Both analytic and N-body models can be sampled by Galaxia. For N-body models, we present a scheme that disperses the stars spawned by an N-body particle, in such a way that the phase space density of the spawned stars is consistent with that of the N-body particles. The code is ideally suited to generating synthetic data sets that mimic near future wide area surveys such as GAIA, LSST and HERMES. In future, we plan to release the code publicly at http://galaxia.sourceforge.net. As an application of the code, we study the prospect of identifying structures in the stellar halo with future surveys that will have velocity information about the stars.

  8. Wetting and Non-Wetting Models of Black Carbon Activation

    Science.gov (United States)

    Henson, B. F.; Laura, S.

    2006-12-01

    We present the results of recent modeling studies on the activation of black carbon (BC) aerosol to form cloud condensation nuclei (CCN). We use a model of BC activation based on a general modification of the Koehler equation for insoluble activation in which we introduce a term based on the activity of water adsorbed on the particle surface. We parameterize the model using the free energy of adsorption, a parameter directly comparable to laboratory measurements of water adsorption on carbon. Although the model of the water- surface interaction is general, the form of the activation equation that results depends upon a further model of the distribution of water on the particle. One possible model involves the symmetric growth of a water shell around the isoluble particle core (wetting). This model predicts upper and lower bounding curves for the activation supersaturation given by the range of water interaction energies from hydrophobic to hydrophilic which are in agreement with a large body of recent activation data. The resulting activation diameters are from 3 to 10 times smaller than activation of soluble particles of identical dry diameter. Another possible model involves an exluded liquid droplet growing in contact with the particle (non-wetting). The geometry of this model much more resembles classic assumptions of heterogeneous nucleation theory. This model can yield extremely high activation supersaturation as a function of diameter, as has been observed in some experiments, and enables calculations in agreement with some of these results. We discuss these two geometrical models of water growth, the different behaviors predicted by the resulting activation equation, and the means to determine which model of growth is appropriate for a given BC particle characterized by either water interaction energy or morphology. These simple models enable an efficient and physically reasonable means to calculate the activation of BC aerosol to form CCN based upon a

  9. Legal regime of lobby activities. A comparative view

    Directory of Open Access Journals (Sweden)

    Ovidiu-Horia MAICAN

    2014-12-01

    Full Text Available A very important aspect is that countries with specific rules and regulations regulating the activities of lobbyists and interest groups are more the exception than the rule. The interest groups are pursuing their goals in the political arena by lobbying, or attempting to influence policy-making, are consistent with the spirit of democracy. In practice, interest group influence can sometimes lead to political corruption, the inequality of representation, and the overcrowding of political institutions. As a consequence, some political systems find it appropriate to regulate interest representation.

  10. Modeling and comparative study of fluid velocities in heterogeneous rocks

    Science.gov (United States)

    Hingerl, Ferdinand F.; Romanenko, Konstantin; Pini, Ronny; Balcom, Bruce; Benson, Sally

    2013-04-01

    Detailed knowledge of the distribution of effective porosity and fluid velocities in heterogeneous rock samples is crucial for understanding and predicting spatially resolved fluid residence times and kinetic reaction rates of fluid-rock interactions. The applicability of conventional MRI techniques to sedimentary rocks is limited by internal magnetic field gradients and short spin relaxation times. The approach developed at the UNB MRI Centre combines the 13-interval Alternating-Pulsed-Gradient Stimulated-Echo (APGSTE) scheme and three-dimensional Single Point Ramped Imaging with T1 Enhancement (SPRITE). These methods were designed to reduce the errors due to effects of background gradients and fast transverse relaxation. SPRITE is largely immune to time-evolution effects resulting from background gradients, paramagnetic impurities and chemical shift. Using these techniques quantitative 3D porosity maps as well as single-phase fluid velocity fields in sandstone core samples were measured. Using a new Magnetic Resonance Imaging technique developed at the MRI Centre at UNB, we created 3D maps of porosity distributions as well as single-phase fluid velocity distributions of sandstone rock samples. Then, we evaluated the applicability of the Kozeny-Carman relationship for modeling measured fluid velocity distributions in sandstones samples showing meso-scale heterogeneities using two different modeling approaches. The MRI maps were used as reference points for the modeling approaches. For the first modeling approach, we applied the Kozeny-Carman relationship to the porosity distributions and computed respective permeability maps, which in turn provided input for a CFD simulation - using the Stanford CFD code GPRS - to compute averaged velocity maps. The latter were then compared to the measured velocity maps. For the second approach, the measured velocity distributions were used as input for inversely computing permeabilities using the GPRS CFD code. The computed

  11. Modeling Workflow Using UML Activity Diagram

    Institute of Scientific and Technical Information of China (English)

    Wei Yinxing(韦银星); Zhang Shensheng

    2004-01-01

    An enterprise can improve its adaptability in the changing market by means of workflow technologies. In the build time, the main function of Workflow Management System (WFMS) is to model business process. Workflow model is an abstract representation of the real-world business process. The Unified Modeling Language (UML) activity diagram is an important visual process modeling language proposed by the Object Management Group (OMG). The novelty of this paper is representing workflow model by means of UML activity diagram. A translation from UML activity diagram to π-calculus is established. Using π-calculus, the deadlock property of workflow is analyzed.

  12. Activity Recognition Using Biomechanical Model Based Pose Estimation

    OpenAIRE

    Reiss, Attila; Hendeby, Gustaf; Bleser, Gabriele; Stricker, Didier

    2010-01-01

    In this paper, a novel activity recognition method based on signal-oriented and model-based features is presented. The model-based features are calculated from shoulder and elbow joint angles and torso orientation, provided by upper-body pose estimation based on a biomechanical body model. The recognition performance of signal-oriented and model-based features is compared within this paper, and the potential of improving recognition accuracy by combining the two approaches is proved: the accu...

  13. THE FLAT TAX - A COMPARATIVE STUDY OF THE EXISTING MODELS

    Directory of Open Access Journals (Sweden)

    Schiau (Macavei Laura - Liana

    2011-07-01

    Full Text Available In the two last decades the flat tax systems have spread all around the globe from East and Central Europe to Asia and Central America. Many specialists consider this phenomenon a real fiscal revolution, but others see it as a mistake as long as the new systems are just a feint of the true flat tax designed by the famous Stanford University professors Robert Hall and Alvin Rabushka. In this context this paper tries to determine which of the existing flat tax systems resemble the true flat tax model by comparing and contrasting their main characteristics with the features of the model proposed by Hall and Rabushka. The research also underlines the common features and the differences between the existing models. The idea of this kind of study is not really new, others have done it but the comparison was limited to one country. For example Emil Kalchev from New Bulgarian University has asses the Bulgarian income system, by comparing it with the flat tax and concluding that taxation in Bulgaria is not simple, neutral and non-distortive. Our research is based on several case studies and on compare and contrast qualitative and quantitative methods. The study starts form the fiscal design drawn by the two American professors in the book The Flat Tax. Four main characteristics of the flat tax system were chosen in order to build the comparison: fiscal design, simplicity, avoidance of double taxation and uniformity of the tax rates. The jurisdictions chosen for the case study are countries all around the globe with fiscal systems which are considered flat tax systems. The results obtained show that the fiscal design of Hong Kong is the only flat tax model which is built following an economic logic and not a legal sense, being in the same time a simple and transparent system. Others countries as Slovakia, Albania, Macedonia in Central and Eastern Europe fulfill the requirement regarding the uniformity of taxation. Other jurisdictions avoid the double

  14. Comparing spatial and temporal transferability of hydrological model parameters

    Science.gov (United States)

    Patil, Sopan D.; Stieglitz, Marc

    2015-06-01

    Operational use of hydrological models requires the transfer of calibrated parameters either in time (for streamflow forecasting) or space (for prediction at ungauged catchments) or both. Although the effects of spatial and temporal parameter transfer on catchment streamflow predictions have been well studied individually, a direct comparison of these approaches is much less documented. Here, we compare three different schemes of parameter transfer, viz., temporal, spatial, and spatiotemporal, using a spatially lumped hydrological model called EXP-HYDRO at 294 catchments across the continental United States. Results show that the temporal parameter transfer scheme performs best, with lowest decline in prediction performance (median decline of 4.2%) as measured using the Kling-Gupta efficiency metric. More interestingly, negligible difference in prediction performance is observed between the spatial and spatiotemporal parameter transfer schemes (median decline of 12.4% and 13.9% respectively). We further demonstrate that the superiority of temporal parameter transfer scheme is preserved even when: (1) spatial distance between donor and receiver catchments is reduced, or (2) temporal lag between calibration and validation periods is increased. Nonetheless, increase in the temporal lag between calibration and validation periods reduces the overall performance gap between the three parameter transfer schemes. Results suggest that spatiotemporal transfer of hydrological model parameters has the potential to be a viable option for climate change related hydrological studies, as envisioned in the "trading space for time" framework. However, further research is still needed to explore the relationship between spatial and temporal aspects of catchment hydrological variability.

  15. Curriculum inventory: Modeling, sharing and comparing medical education programs.

    Science.gov (United States)

    Ellaway, Rachel H; Albright, Susan; Smothers, Valerie; Cameron, Terri; Willett, Timothy

    2014-03-01

    Abstract descriptions of how curricula are structured and run. The American National Standards Institute (ANSI) MedBiquitous Curriculum Inventory Standard provides a technical syntax through which a wide range of different curricula can be expressed and subsequently compared and analyzed. This standard has the potential to shift curriculum mapping and reporting from a somewhat disjointed and institution-specific undertaking to something that is shared among multiple medical schools and across whole medical education systems. Given the current explosion of different models of curricula (time-free, competency-based, socially accountable, distributed, accelerated, etc.), the ability to consider this diversity using a common model has particular value in medical education management and scholarship. This article describes the development and structure of the Curriculum Inventory Standard as a way of standardizing the modeling of different curricula for audit, evaluation and research purposes. It also considers the strengths and limitations of the current standard and the implications for a medical education world in which this level of commonality, precision, and accountability for curricular practice is the norm rather than the exception.

  16. An overview of comparative modelling and resources dedicated to large-scale modelling of genome sequences.

    Science.gov (United States)

    Lam, Su Datt; Das, Sayoni; Sillitoe, Ian; Orengo, Christine

    2017-08-01

    Computational modelling of proteins has been a major catalyst in structural biology. Bioinformatics groups have exploited the repositories of known structures to predict high-quality structural models with high efficiency at low cost. This article provides an overview of comparative modelling, reviews recent developments and describes resources dedicated to large-scale comparative modelling of genome sequences. The value of subclustering protein domain superfamilies to guide the template-selection process is investigated. Some recent cases in which structural modelling has aided experimental work to determine very large macromolecular complexes are also cited.

  17. [Antitumor Activity of Polysaccharides from Ganoderma lucidum Mycelium: in vivo Comparative Study].

    Science.gov (United States)

    Krasnopolskaya, L M; Yarina, M S; Avtonomova, A V; Usov, A I; Isakova, E B; Bukchman, V M

    2015-01-01

    Fractions of water soluble and alkali soluble polysaccharides, as well as fucogalactan, a water soluble polysaccharide, and xylomannan, an alkali soluble polysaccharide, were isolated from the Ganoderma lucidum submerged mycelium. When administered orally, the polysaccharides showed antitumor activity in vivo on murine models of solid tumors. Xylomannan and fucogalactan showed the highest antitumor activity. Sensitivity to xylomannan was more pronounced in adenocarcinoma Ca755 as compared to the T-cell lymphocytic leukemia P388. The antitumor activity of the water soluble polysaccharides total fractions from the mycelium and fruiting bodies of the G. lucidum strain was almost identical. The maximum antitumor effect of the mycelium water soluble polysaccharides total fraction was observed with the use of the daily dose of 2 mg/kg.

  18. Discursive Positionings and Emotions in Modelling Activities

    Science.gov (United States)

    Daher, Wajeeh

    2015-01-01

    Mathematical modelling is suggested as an activity through which students engage in meaningful mathematics. In the current research, the modelling activity of a group of four seventh-grade students was analysed using the discursive analysis framework. The research findings show that the positionings and emotions of the group members during their…

  19. Students’ mathematical learning in modelling activities

    DEFF Research Database (Denmark)

    Kjeldsen, Tinne Hoff; Blomhøj, Morten

    2013-01-01

    Ten years of experience with analyses of students’ learning in a modelling course for first year university students, led us to see modelling as a didactical activity with the dual goal of developing students’ modelling competency and enhancing their conceptual learning of mathematical concepts...... involved. We argue that progress in students’ conceptual learning needs to be conceptualised separately from that of progress in their modelling competency. Findings are that modelling activities open a window to the students’ images of the mathematical concepts involved; that modelling activities can...... create and help overcome hidden cognitive conflicts in students’ understanding; that reflections within modelling can play an important role for the students’ learning of mathematics. These findings are illustrated with a modelling project concerning the world population....

  20. Modelling Typical Online Language Learning Activity

    Science.gov (United States)

    Montoro, Carlos; Hampel, Regine; Stickler, Ursula

    2014-01-01

    This article presents the methods and results of a four-year-long research project focusing on the language learning activity of individual learners using online tasks conducted at the University of Guanajuato (Mexico) in 2009-2013. An activity-theoretical model (Blin, 2010; Engeström, 1987) of the typical language learning activity was used to…

  1. Evaluating a Model of Youth Physical Activity

    Science.gov (United States)

    Heitzler, Carrie D.; Lytle, Leslie A.; Erickson, Darin J.; Barr-Anderson, Daheia; Sirard, John R.; Story, Mary

    2010-01-01

    Objective: To explore the relationship between social influences, self-efficacy, enjoyment, and barriers and physical activity. Methods: Structural equation modeling examined relationships between parent and peer support, parent physical activity, individual perceptions, and objectively measured physical activity using accelerometers among a…

  2. Comparing Transformation Possibilities of Topological Functioning Model and BPMN in the Context of Model Driven Architecture

    Directory of Open Access Journals (Sweden)

    Solomencevs Artūrs

    2016-05-01

    Full Text Available The approach called “Topological Functioning Model for Software Engineering” (TFM4SE applies the Topological Functioning Model (TFM for modelling the business system in the context of Model Driven Architecture. TFM is a mathematically formal computation independent model (CIM. TFM4SE is compared to an approach that uses BPMN as a CIM. The comparison focuses on CIM modelling and on transformation to UML Sequence diagram on the platform independent (PIM level. The results show the advantages and drawbacks the formalism of TFM brings into the development.

  3. Comparing spatial and temporal transferability of hydrological model parameters

    Science.gov (United States)

    Patil, Sopan; Stieglitz, Marc

    2015-04-01

    Operational use of hydrological models requires the transfer of calibrated parameters either in time (for streamflow forecasting) or space (for prediction at ungauged catchments) or both. Although the effects of spatial and temporal parameter transfer on catchment streamflow predictions have been well studied individually, a direct comparison of these approaches is much less documented. In our view, such comparison is especially pertinent in the context of increasing appeal and popularity of the "trading space for time" approaches that are proposed for assessing the hydrological implications of anthropogenic climate change. Here, we compare three different schemes of parameter transfer, viz., temporal, spatial, and spatiotemporal, using a spatially lumped hydrological model called EXP-HYDRO at 294 catchments across the continental United States. Results show that the temporal parameter transfer scheme performs best, with lowest decline in prediction performance (median decline of 4.2%) as measured using the Kling-Gupta efficiency metric. More interestingly, negligible difference in prediction performance is observed between the spatial and spatiotemporal parameter transfer schemes (median decline of 12.4% and 13.9% respectively). We further demonstrate that the superiority of temporal parameter transfer scheme is preserved even when: (1) spatial distance between donor and receiver catchments is reduced, or (2) temporal lag between calibration and validation periods is increased. Nonetheless, increase in the temporal lag between calibration and validation periods reduces the overall performance gap between the three parameter transfer schemes. Results suggest that spatiotemporal transfer of hydrological model parameters has the potential to be a viable option for climate change related hydrological studies, as envisioned in the "trading space for time" framework. However, further research is still needed to explore the relationship between spatial and temporal

  4. Comparative pharmacological evaluation of adaptogenic activity of Holoptelea integrifolia and Withania somnifera

    Directory of Open Access Journals (Sweden)

    Shakti Puri

    2011-03-01

    Full Text Available The present work was planned to compare adaptogenic activity of ethanolic extracts of Holoptelea integrifolia (ETHEHI 250 mg/kg and ETHEHI 500 mg/kg with Withania somnifera (ETHEWS 100 mg/kg using forced swimming endurance test and Chronic cold restraint stress models. Based on the results, it can be concluded that both 250mg/kg and 500mg/kg doses of ethanolic extract of Holoptelea integrifolia showed adaptogenic activity and this activity was closer to the activity of 100mg/kg of Withania somnifera. The adaptogenic activity was dose dependent in ethanolic extract of Holoptelea integrifolia. These effects may be due to the presence of tannins, saponins, alkaloids, phenolics, flavonoids in the extract of bark of Holoptelea integrifolia as flavonoids, tannins and phenolics are mainly responsible for adaptogenic activity. Adaptogens have not only specific therapeutic effects in some stress induced and stress related disorders, but will also have an impact on the quality of life of patients.

  5. Time-driven activity based costing: a comparative study with the activity based costing

    Directory of Open Access Journals (Sweden)

    Marina Battistella Luna

    2017-06-01

    Full Text Available The activity-based costing (ABC emerged in the 1980s to meet the new necessities of cost information facing companies, the result of continuous changes in the business environment. In the 2000s, a new costing method, known as time-driven activity-based costing (TDABC was introduced in order to simplify the ABC. This paper compares these methods in order to provide information to assist managers to decide which of these methods better suits the reality of their companies. Therefore, they were analyzed based on information obtained through a systematic search in the Scopus and Web of Knowledge databases, as well as papers from the annals of the Congresso Brasileiro de Custos, Congresso de Controladoria e Contabilidade da USP and Encontro Nacional de Engenharia de Produção (considering scientific papers published between 2004 and 2016. From this analysis, in most cases it was concluded that TDABC is a simpler and more practical option than ABC. However, it was also apparent that managers, before choosing a particular method, must verify whether the conditions that enable its applicability exist.

  6. Comparing Epileptiform Behavior of Mesoscale Detailed Models and Population Models of Neocortex

    NARCIS (Netherlands)

    Visser, Sid; Meijer, Hil G.E.; Lee, Hyong C.; Drongelen, van Wim; Putten, van Michel J.A.M; Gils, van Stephan A.

    2010-01-01

    Two models of the neocortex are developed to study normal and pathologic neuronal activity. One model contains a detailed description of a neocortical microcolumn represented by 656 neurons, including superficial and deep pyramidal cells, four types of inhibitory neurons, and realistic synaptic cont

  7. Comparing interval estimates for small sample ordinal CFA models.

    Science.gov (United States)

    Natesan, Prathiba

    2015-01-01

    Robust maximum likelihood (RML) and asymptotically generalized least squares (AGLS) methods have been recommended for fitting ordinal structural equation models. Studies show that some of these methods underestimate standard errors. However, these studies have not investigated the coverage and bias of interval estimates. An estimate with a reasonable standard error could still be severely biased. This can only be known by systematically investigating the interval estimates. The present study compares Bayesian, RML, and AGLS interval estimates of factor correlations in ordinal confirmatory factor analysis models (CFA) for small sample data. Six sample sizes, 3 factor correlations, and 2 factor score distributions (multivariate normal and multivariate mildly skewed) were studied. Two Bayesian prior specifications, informative and relatively less informative were studied. Undercoverage of confidence intervals and underestimation of standard errors was common in non-Bayesian methods. Underestimated standard errors may lead to inflated Type-I error rates. Non-Bayesian intervals were more positive biased than negatively biased, that is, most intervals that did not contain the true value were greater than the true value. Some non-Bayesian methods had non-converging and inadmissible solutions for small samples and non-normal data. Bayesian empirical standard error estimates for informative and relatively less informative priors were closer to the average standard errors of the estimates. The coverage of Bayesian credibility intervals was closer to what was expected with overcoverage in a few cases. Although some Bayesian credibility intervals were wider, they reflected the nature of statistical uncertainty that comes with the data (e.g., small sample). Bayesian point estimates were also more accurate than non-Bayesian estimates. The results illustrate the importance of analyzing coverage and bias of interval estimates, and how ignoring interval estimates can be misleading

  8. Comparing Entrepreneurship Intention: A Multigroup Structural Equation Modeling Approach

    Directory of Open Access Journals (Sweden)

    Sabrina O. Sihombing

    2012-04-01

    Full Text Available Unemployment is one of the main social and economic problems that many countries face nowadays. One strategic way to overcome this problem is by fostering entrepreneurship spirit especially for unem-ployment graduates. Entrepreneurship is becoming an alternative Job for students after they graduate. This is because entrepreneurship of fers major benefits, such as setting up one’s own business and the pos sibility of having significant financial rewards than working for others. Entrepreneurship is then offered by many universities. This research applies the theory of planned behavior (TPB by incorporating attitude toward success as an antecedent variable of the attitude to examine students’ intention to become an entrepreneur. The objective of this research is to compare entrepreneurship intention between business students and non-business students. A self-administered questionnaire was used to collect data for this study. Questionnaires were distributed to respondents by applying the drop-off/pick-up method. A number of 294 by questionnaires were used in the analysis. Data were analyzed by using structural equation modeling. Two out of four hypotheses were confirmed. These hypotheses are the relationship between the attitude toward becoming an entrepreneur and the intention to try becoming an entrepreneur, and the relationship perceived behavioral control and intention to try becoming an entrepreneur. This paper also provides a discussion and offers directions for future research.

  9. Comparing Entrepreneurship Intention: A Multigroup Structural Equation Modeling Approach

    Directory of Open Access Journals (Sweden)

    Sabrina O. Sihombing

    2012-04-01

    Full Text Available Unemployment is one of the main social and economic problems that many countries face nowadays. One strategic way to overcome this problem is by fostering entrepreneurship spirit especially for unem ployment graduates. Entrepreneurship is becoming an alternative Job for students after they graduate. This is because entrepreneurship of-fers major benefits, such as setting up one’s own business and the pos-sibility of having significant financial rewards than working for others. Entrepreneurship is then offered by many universities. This research applies the theory of planned behavior (TPB by incorporating attitude toward success as an antecedent variable of the attitude to examine students’ intention to become an entrepreneur. The objective of this research is to compare entrepreneurship intention between business students and non-business students. A self-administered questionnaire was used to collect data for this study. Questionnaires were distributed to respondents by applying the drop-off/pick-up method. A number of 294 by questionnaires were used in the analysis. Data were analyzed by using structural equation modeling. Two out of four hypotheses were confirmed. These hypotheses are the relationship between the attitude toward becoming an entrepreneur and the intention to try becoming an entrepreneur, and the relationship perceived behavioral control and intention to try becoming an entrepreneur. This paper also provides a discussion and offers directions for future research.

  10. Comparative Studies of the Adsorption of Direct Dye on Activated Carbon and Conducting Polymer Composite

    Directory of Open Access Journals (Sweden)

    J. Raffiea Baseri

    2012-01-01

    Full Text Available This study analyses the feasibility of removing Direct Blue 71 from aqueous solution by different adsorbents such as activated carbon (TPAC and Poly pyrrole polymer composite (PPC prepared from Thevetia Peruviana. Batch mode adsorption was performed to investigate the adsorption capacities of these adsorbents by varying initial dye concentration, temperature, agitation time and pH. The performance of TPAC was compared with PPC. Among the adsorbents, PPC had more adsorption capacity (88.24% than TPAC (58.82% at an initial concentration of 50 mg/L and at 30°C. The experimental data best fitted with pseudo second order kinetic model. The adsorption data fitted well for Langmuir adsorption isotherm. Thermodynamic parameters for the adsorbents were also evaluated. The carbon embedded in conducting polymers matrix show better adsorptive properties than activated carbon.

  11. Comparative metagenomics demonstrating different degradative capacity of activated biomass treating hydrocarbon contaminated wastewater.

    Science.gov (United States)

    Yadav, Trilok Chandra; Pal, Rajesh Ramavadh; Shastri, Sunita; Jadeja, Niti B; Kapley, Atya

    2015-01-01

    This study demonstrates the diverse degradative capacity of activated biomass, when exposed to different levels of total dissolved solids (TDS) using a comparative metagenomics approach. The biomass was collected at two time points to examine seasonal variations. Four metagenomes were sequenced on Illumina Miseq platform and analysed using MG-RAST. STAMP tool was used to analyse statistically significant differences amongst different attributes of metagenomes. Metabolic pathways related to degradation of aromatics via the central and peripheral pathways were found to be dominant in low TDS metagenome, while pathways corresponding to central carbohydrate metabolism, nitrogen, organic acids were predominant in high TDS sample. Seasonal variation was seen to affect catabolic gene abundance as well as diversity of the microbial community. Degradation of model compounds using activated sludge demonstrated efficient utilisation of single aromatic ring compounds in both samples but cyclic compounds were not efficiently utilised by biomass exposed to high TDS.

  12. Nanoscale charge transport in cytochrome c3/DNA network: Comparative studies between redox-active molecules

    Science.gov (United States)

    Yamaguchi, Harumasa; Che, Dock-Chil; Hirano, Yoshiaki; Suzuki, Masayuki; Higuchi, Yoshiki; Matsumoto, Takuya

    2015-09-01

    The redox-active molecule of a cytochrome c3/DNA network exhibits nonlinear current-voltage (I-V) characteristics with a threshold bias voltage at low temperature and zero-bias conductance at room temperature. I-V curves for the cytochrome c3/DNA network are well matched with the Coulomb blockade network model. Comparative studies of the Mn12 cluster, cytochrome c, and cytochrome c3, which have a wide variety of redox potentials, indicate no difference in charge transport, which suggests that the conduction mechanism is not directly related to the redox states. The charge transport mechanism has been discussed in terms of the newly-formed electronic energy states near the Fermi level, induced by the ionic interaction between redox-active molecules with the DNA network.

  13. Comparative Evaluation of the Antimicrobial Activity of Different Antimicrobial Peptides against a Range of Pathogenic Bacteria

    DEFF Research Database (Denmark)

    Ebbensgaard, Anna Elisabeth; Mordhorst, Hanne; Overgaard, Michael Toft

    2015-01-01

    The rapid emergence of resistance to classical antibiotics has increased the interest in novel antimicrobial compounds. Antimicrobial peptides (AMPs) represent an attractive alternative to classical antibiotics and a number of different studies have reported antimicrobial activity data of various...... AMPs, but there is only limited comparative data available. The mode of action for many AMPs is largely unknown even though several models have suggested that the lipopolysaccharides (LPS) play a crucial role in the attraction and attachment of the AMP to the bacterial membrane in Gram......-negative bacteria. We compared the potency of Cap18, Cap11, Cap11-1-18m2, Cecropin P1, Cecropin B, Bac2A, Bac2A-NH2, Sub5-NH2, Indolicidin, Melittin, Myxinidin, Myxinidin-NH2, Pyrrhocoricin, Apidaecin and Metalnikowin I towards Staphylococcus aureus, Enterococcus faecalis, Pseudomonas aeruginosa, Escherichia coli...

  14. Activity-based resource capability modeling

    Institute of Scientific and Technical Information of China (English)

    CHENG Shao-wu; XU Xiao-fei; WANG Gang; SUN Xue-dong

    2008-01-01

    To analyse and optimize a enterprise process in a wide scope, an activity-based method of modeling resource capabilities is presented. It models resource capabilities by means of the same structure as an activity, that is, resource capabilities are defined by input objects, actions and output objects. A set of activity-based re-source capability modeling rules and matching rules between an activity and a resource are introduced. This method can not only be used to describe capability of manufacturing tools, but also capability of persons and applications, etc. It unifies methods of modeling capability of all kinds of resources in an enterprise and supports the optimization of the resource allocation of a process.

  15. Incremental activity modeling in multiple disjoint cameras.

    Science.gov (United States)

    Loy, Chen Change; Xiang, Tao; Gong, Shaogang

    2012-09-01

    Activity modeling and unusual event detection in a network of cameras is challenging, particularly when the camera views are not overlapped. We show that it is possible to detect unusual events in multiple disjoint cameras as context-incoherent patterns through incremental learning of time delayed dependencies between distributed local activities observed within and across camera views. Specifically, we model multicamera activities using a Time Delayed Probabilistic Graphical Model (TD-PGM) with different nodes representing activities in different decomposed regions from different views and the directed links between nodes encoding their time delayed dependencies. To deal with visual context changes, we formulate a novel incremental learning method for modeling time delayed dependencies that change over time. We validate the effectiveness of the proposed approach using a synthetic data set and videos captured from a camera network installed at a busy underground station.

  16. Comparative analysis of business rules and business process modeling languages

    Directory of Open Access Journals (Sweden)

    Audrius Rima

    2013-03-01

    Full Text Available During developing an information system is important to create clear models and choose suitable modeling languages. The article analyzes the SRML, SBVR, PRR, SWRL, OCL rules specifying language and UML, DFD, CPN, EPC and IDEF3 BPMN business process modeling language. The article presents business rules and business process modeling languages theoretical comparison. The article according to selected modeling aspects of the comparison between different business process modeling languages ​​and business rules representation languages sets. Also, it is selected the best fit of language set for three layer framework for business rule based software modeling.

  17. Modeling Blood Pressure:Comparative Study Of Seemingly ...

    African Journals Online (AJOL)

    persons engaged in occupations involving little physical activity than those who are more active (Mial, 1959;. Idahosa, 1987). ..... prevalence and biosocial determinants of high blood pressure in a group of urban Nigerians. J. Hum Hypertens.

  18. Modelling constructed wetlands: scopes and aims - a comparative review

    OpenAIRE

    Meyer, D; Chazarenc, Florent; Claveau Mallet, D.; Dittmer, D; Forquet, N.; Molle, P.; Morvannou, A.; Palfy, T.; Petitjean, A; Rizzo, A.; Samso Campa, R.; Scholz, M.; Soric, Audrey; Langergraber, G.

    2015-01-01

    International audience; During the last two decades a couple of models were developed for constructed wetlands with differing purposes. Meanwhile the usage of this kind of tool is generally accepted, but the misuse of the models still confirms the skepticism. Generally three some groups of models can be distinguished: On one hand mechanistic models try to display the complex and diffuse interaction of occurring processes, on the other hand the same kind of models is are used to investigate si...

  19. Comparative study on mode split discrete choice models

    Institute of Scientific and Technical Information of China (English)

    Xianlong Chen; Xiaoqian Liu; Fazhi Li

    2013-01-01

    Discrete choice model acts as one of the most important tools for studies involving mode split in the context of transport demand forecast. As different types of discrete choice models display their merits and restrictions diversely, how to properly select the specific type among discrete choice models for realistic application still remains to be a tough problem. In this article, five typical discrete choice models for transport mode split are, respectively, discussed, which includes multinomial logit model, nested logit model (NL), heteroscedastic extreme value model, multinominal probit model and mixed multinomial logit model (MMNL). The theoretical basis and application attributes of these five models are especially analysed with great attention, and they are also applied to a realistic intercity case of mode split forecast, which results indi-cating that NL model does well in accommodating simi-larity and heterogeneity across alternatives, while MMNL model serves as the most effective method for mode choice prediction since it shows the highest reliability with the least significant prediction errors and even outperforms the other four models in solving the heterogeneity and similarity problems. This study indicates that conclusions derived from a single discrete choice model are not reli-able, and it is better to choose the proper model based on its characteristics.

  20. Comparative assessment of three-phase oil relative permeability models

    Science.gov (United States)

    Ranaee, Ehsan; Riva, Monica; Porta, Giovanni M.; Guadagnini, Alberto

    2016-07-01

    We assess the ability of 11 models to reproduce three-phase oil relative permeability (kro) laboratory data obtained in a water-wet sandstone sample. We do so by considering model performance when (i) solely two-phase data are employed to render predictions of kro and (ii) two and three-phase data are jointly used for model calibration. In the latter case, a Maximum Likelihood (ML) approach is used to estimate model parameters. The tested models are selected among (i) classical models routinely employed in practical applications and implemented in commercial reservoir software and (ii) relatively recent models which are considered to allow overcoming some drawbacks of the classical formulations. Among others, the latter set of models includes the formulation recently proposed by Ranaee et al., which has been shown to embed the critical effects of hysteresis, including the reproduction of oil remobilization induced by gas injection in water-wet media. We employ formal model discrimination criteria to rank models according to their skill to reproduce the observed data and use ML Bayesian model averaging to provide model-averaged estimates (and associated uncertainty bounds) of kro by taking advantage of the diverse interpretive abilities of all models analyzed. The occurrence of elliptic regions is also analyzed for selected models in the framework of the classical fractional flow theory of displacement. Our study confirms that model outcomes based on channel flow theory and classical saturation-weighted interpolation models do not generally yield accurate reproduction of kro data, especially in the regime associated with low oil saturations, where water alternating gas injection (WAG) techniques are usually employed for enhanced oil recovery. This negative feature is not observed in the model of Ranaee et al. (2015) due to its ability to embed key effects of pore-scale phase distributions, such as hysteresis effects and cycle dependency, for modeling kro observed

  1. Orthodontic measurements on digital study models compared with plaster models: a systematic review.

    Science.gov (United States)

    Fleming, P S; Marinho, V; Johal, A

    2011-02-01

    The aim of this study is to evaluate the validity of the use of digital models to assess tooth size, arch length, irregularity index, arch width and crowding versus measurements generated on hand-held plaster models with digital callipers in patients with and without malocclusion. Studies comparing linear and angular measurements obtained on digital and standard plaster models were identified by searching multiple databases including MEDLINE, LILACS, BBO, ClinicalTrials.gov, the National Research Register and Pro-Quest Dissertation Abstracts and Thesis database, without restrictions relating to publication status or language of publication. Two authors were involved in study selection, quality assessment and the extraction of data. Items from the Quality Assessment of Studies of Diagnostic Accuracy included in Systematic Reviews checklist were used to assess the methodological quality of included studies. No meta-analysis was conducted. Comparisons between measurements of digital and plaster models made directly within studies were reported, and the difference between the (repeated) measurement means for digital and plaster models were considered as estimates. Seventeen relevant studies were included. Where reported, overall, the absolute mean differences between direct and indirect measurements on plaster and digital models were minor and clinically insignificant. Orthodontic measurements with digital models were comparable to those derived from plaster models. The use of digital models as an alternative to conventional measurement on plaster models may be recommended, although the evidence identified in this review is of variable quality. © 2010 John Wiley & Sons A/S.

  2. Comparative Efficacies of Antibiotics in a Rat Model of Meningoencephalitis Due to Listeria monocytogenes

    OpenAIRE

    Michelet, Christian; Leib, Stephen L.; Bentue-Ferrer, Daniele; Täuber, Martin G.

    1999-01-01

    The antibacterial activities of amoxicillin-gentamicin, trovafloxacin, trimethoprim-sulfamethoxazole (TMP-SMX) and the combination of trovafloxacin with TMP-SMX were compared in a model of meningoencephalitis due to Listeria monocytogenes in infant rats. At 22 h after intracisternal infection, the cerebrospinal fluid was cultured to document meningitis, and the treatment was started. Treatment was instituted for 48 h, and efficacy was evaluated 24 h after administration of the last dose. All ...

  3. A Comparative Metroscope Model for Urban Information Flows

    Science.gov (United States)

    Fink, J. H.; Shandas, V.; Beaudoin, F.

    2011-12-01

    One of the most promising ways to achieve global sustainability goals of climate stabilization, poverty reduction, and biodiversity preservation is to make the world's cities more efficient, equitable, and healthful. While each city must follow a unique and somewhat idiosyncratic path toward these linked goals based on its history, geography, demography, and politics, movement in this direction can accelerate if cities can learn from each other more effectively. Such learning requires the identification of common characteristics and methodologies. We have created a framework for organizing and applying urban information flows, which we refer to as "Metroscopes." Metroscopes, which are analogous to the large instruments that have advanced the physical and life sciences, integrate six elements: data collection and input; classification through the use of metrics; data storage and retrieval; analytics and modeling; decision support including visualization and scenario generation; and assessment of the effectiveness of policy choices. Standards for each of these elements can be agreed upon by relevant urban science and policy sub-communities, and then can evolve as technologies and practices advance. We are implementing and calibrating this approach using data and relationships from Portland (OR), Phoenix (AZ) and London (UK). Elements that are being integrated include the Global City Indicators Facility at University of Toronto, the J-Earth database system and Decision Theater from Arizona State University, urban mobility analyses performed by the SENSEable City Lab at MIT, and Portland's Ecodistrict approach for urban management. Individual Metroscopes can be compared directly from one city to another, or with larger assemblages of cities like those being classified by ICLEI's STAR program, the Clinton Climate Initiative's C40, and Siemens Green Cities Index. This large-scale integration of urban data sets and approaches and its systematic comparison are key steps

  4. Learning models of activities involving interacting objects

    DEFF Research Database (Denmark)

    Manfredotti, Cristina; Pedersen, Kim Steenstrup; Hamilton, Howard J.;

    2013-01-01

    We propose the LEMAIO multi-layer framework, which makes use of hierarchical abstraction to learn models for activities involving multiple interacting objects from time sequences of data concerning the individual objects. Experiments in the sea navigation domain yielded learned models that were...

  5. Capturing Appearance Variation in Active Appearance Models

    NARCIS (Netherlands)

    Van der Maaten, L.J.P.; Hendriks, E.A.

    2010-01-01

    The paper presents an extension of active appearance models (AAMs) that is better capable of dealing with the large variation in face appearance that is encountered in large multi-person face data sets. Instead of the traditional PCA-based texture model, our extended AAM employs a mixture of probabi

  6. Learning models of activities involving interacting objects

    DEFF Research Database (Denmark)

    Manfredotti, Cristina; Pedersen, Kim Steenstrup; Hamilton, Howard J.

    2013-01-01

    We propose the LEMAIO multi-layer framework, which makes use of hierarchical abstraction to learn models for activities involving multiple interacting objects from time sequences of data concerning the individual objects. Experiments in the sea navigation domain yielded learned models that were t...

  7. Comparing graphene, carbon nanotubes, and superfine powdered activated carbon as adsorptive coating materials for microfiltration membranes.

    Science.gov (United States)

    Ellerie, Jaclyn R; Apul, Onur G; Karanfil, Tanju; Ladner, David A

    2013-10-15

    Multi-walled carbon nanotubes (MWCNTs), nano-graphene platelets (NGPs), and superfine powdered activated carbon (S-PAC) were comparatively evaluated for their applicability as adsorptive coatings on microfiltration membranes. The objective was to determine which materials were capable of contaminant removal while causing minimal flux reduction. Methylene blue and atrazine were the model contaminants. When applied as membrane coatings, MWCNTs had minimal retention capabilities for the model contaminants, and S-PAC had the fastest removal. The membrane coating approach was also compared with a stirred vessel configuration, in which the adsorbent was added to a stirred flask preceding the membrane cell. Direct application of the adsorbent to the membrane constituted a greater initial reduction in permeate concentrations of the model contaminants than with the stirred flask setup. All adsorbents except S-PAC showed flux reductions less than 5% after application as thin-layer membrane coatings, and flux recovery after membrane backwashing was greater than 90% for all materials and masses tested.

  8. Modelling the Active Hearing Process in Mosquitoes

    Science.gov (United States)

    Avitabile, Daniele; Homer, Martin; Jackson, Joe; Robert, Daniel; Champneys, Alan

    2011-11-01

    A simple microscopic mechanistic model is described of the active amplification within the Johnston's organ of the mosquito species Toxorhynchites brevipalpis. The model is based on the description of the antenna as a forced-damped oscillator coupled to a set of active threads (ensembles of scolopidia) that provide an impulsive force when they twitch. This twitching is in turn controlled by channels that are opened and closed if the antennal oscillation reaches a critical amplitude. The model matches both qualitatively and quantitatively with recent experiments. New results are presented using mathematical homogenization techniques to derive a mesoscopic model as a simple oscillator with nonlinear force and damping characteristics. It is shown how the results from this new model closely resemble those from the microscopic model as the number of threads approach physiologically correct values.

  9. Comparative evaluation of kinetic, equilibrium and semi-equilibrium models for biomass gasification

    Energy Technology Data Exchange (ETDEWEB)

    Buragohain, Buljit [Center for Energy, Indian Institute of Technology Guwahati, Guwahati – 781 039, Assam (India); Chakma, Sankar; Kumar, Peeush [Department of Chemical Engineering, Indian Institute of Technology Guwahati, Guwahati – 781 039, Assam (India); Mahanta, Pinakeswar [Center for Energy, Indian Institute of Technology Guwahati, Guwahati – 781 039, Assam (India); Department of Mechanical Engineering, Indian Institute of Technology Guwahati, Guwahati – 781 039, Assam (India); Moholkar, Vijayanand S. [Center for Energy, Indian Institute of Technology Guwahati, Guwahati – 781 039, Assam (India); Department of Chemical Engineering, Indian Institute of Technology Guwahati, Guwahati – 781 039, Assam (India)

    2013-07-01

    Modeling of biomass gasification has been an active area of research for past two decades. In the published literature, three approaches have been adopted for the modeling of this process, viz. thermodynamic equilibrium, semi-equilibrium and kinetic. In this paper, we have attempted to present a comparative assessment of these three types of models for predicting outcome of the gasification process in a circulating fluidized bed gasifier. Two model biomass, viz. rice husk and wood particles, have been chosen for analysis, with gasification medium being air. Although the trends in molar composition, net yield and LHV of the producer gas predicted by three models are in concurrence, significant quantitative difference is seen in the results. Due to rather slow kinetics of char gasification and tar oxidation, carbon conversion achieved in single pass of biomass through the gasifier, calculated using kinetic model, is quite low, which adversely affects the yield and LHV of the producer gas. Although equilibrium and semi-equilibrium models reveal relative insensitivity of producer gas characteristics towards temperature, the kinetic model shows significant effect of temperature on LHV of the gas at low air ratios. Kinetic models also reveal volume of the gasifier to be an insignificant parameter, as the net yield and LHV of the gas resulting from 6 m and 10 m riser is same. On a whole, the analysis presented in this paper indicates that thermodynamic models are useful tools for quantitative assessment of the gasification process, while kinetic models provide physically more realistic picture.

  10. Comparative evaluation of kinetic, equilibrium and semi-equilibrium models for biomass gasification

    Directory of Open Access Journals (Sweden)

    Buljit Buragohain, Sankar Chakma, Peeush Kumar, Pinakeswar Mahanta, Vijayanand S. Moholkar

    2013-01-01

    Full Text Available Modeling of biomass gasification has been an active area of research for past two decades. In the published literature, three approaches have been adopted for the modeling of this process, viz. thermodynamic equilibrium, semi-equilibrium and kinetic. In this paper, we have attempted to present a comparative assessment of these three types of models for predicting outcome of the gasification process in a circulating fluidized bed gasifier. Two model biomass, viz. rice husk and wood particles, have been chosen for analysis, with gasification medium being air. Although the trends in molar composition, net yield and LHV of the producer gas predicted by three models are in concurrence, significant quantitative difference is seen in the results. Due to rather slow kinetics of char gasification and tar oxidation, carbon conversion achieved in single pass of biomass through the gasifier, calculated using kinetic model, is quite low, which adversely affects the yield and LHV of the producer gas. Although equilibrium and semi-equilibrium models reveal relative insensitivity of producer gas characteristics towards temperature, the kinetic model shows significant effect of temperature on LHV of the gas at low air ratios. Kinetic models also reveal volume of the gasifier to be an insignificant parameter, as the net yield and LHV of the gas resulting from 6 m and 10 m riser is same. On a whole, the analysis presented in this paper indicates that thermodynamic models are useful tools for quantitative assessment of the gasification process, while kinetic models provide physically more realistic picture.

  11. Comparing three models to estimate transpiration of desert shrubs

    Science.gov (United States)

    Xu, Shiqin; Yu, Zhongbo; Ji, Xibin; Sudicky, Edward A.

    2017-07-01

    The role of environmental variables in controlling transpiration (Ec) is an important, but not well-understood, aspect of transpiration modeling in arid desert regions. Taking three dominant desert shrubs, Haloxylon ammodendron, Nitraria tangutorum, and Calligonum mongolicum, as examples, we aim to evaluate the applicability of three transpiration models, i.e. the modified Jarvis-Stewart model (MJS), the simplified process-based model (BTA), and the artificial neural network model (ANN) at different temporal scales. The stem sap flow of each species was monitored using the stem heat balance approach over both the 2014 and 2015 main growing seasons. Concurrent environmental variables were also measured with an automatic weather station. The ANN model generally produced better simulations of Ec than the MJS and BTA models at both hourly and daily scales, indicating its advantage in solving complicated, nonlinear problems between transpiration rate and environmental driving forces. The solar radiation and vapor pressure deficit were crucial variables in modeling Ec for all three species. The performance of the MJS and ANN models was significantly improved by incorporating root-zone soil moisture. We also found that the difference between hourly and daily fitted parameter values was considerable for the MJS and BTA models. Therefore, these models need to be recalibrated when applied at different temporal scales. This study provides insights regarding the application and performance of current transpiration models in arid desert regions, and thus provides a deeper understanding of eco-hydrological processes and sustainable ecosystem management at the study site.

  12. A Model of Comparative Ethics Education for Social Workers

    Science.gov (United States)

    Pugh, Greg L.

    2017-01-01

    Social work ethics education models have not effectively engaged social workers in practice in formal ethical reasoning processes, potentially allowing personal bias to affect ethical decisions. Using two of the primary ethical models from medicine, a new social work ethics model for education and practical application is proposed. The strengths…

  13. A comparative analysis of pricing models for enterprise cloud platforms

    CSIR Research Space (South Africa)

    Mvelase, P

    2013-09-01

    Full Text Available virtual enterprise (VE)-enabled cloud enterprise architecture for small medium and micro enterprises (SMMEs) against EC2 pricing model to prove that our pricing model is more suitable for small medium and micro enterprises (SMMEs). This model is based...

  14. Predicting the fate of biodiversity using species' distribution models: enhancing model comparability and repeatability.

    Directory of Open Access Journals (Sweden)

    Genoveva Rodríguez-Castañeda

    Full Text Available Species distribution modeling (SDM is an increasingly important tool to predict the geographic distribution of species. Even though many problems associated with this method have been highlighted and solutions have been proposed, little has been done to increase comparability among studies. We reviewed recent publications applying SDMs and found that seventy nine percent failed to report methods that ensure comparability among studies, such as disclosing the maximum probability range produced by the models and reporting on the number of species occurrences used. We modeled six species of Falco from northern Europe and demonstrate that model results are altered by (1 spatial bias in species' occurrence data, (2 differences in the geographic extent of the environmental data, and (3 the effects of transformation of model output to presence/absence data when applying thresholds. Depending on the modeling decisions, forecasts of the future geographic distribution of Falco ranged from range contraction in 80% of the species to no net loss in any species, with the best model predicting no net loss of habitat in Northern Europe. The fact that predictions of range changes in response to climate change in published studies may be influenced by decisions in the modeling process seriously hampers the possibility of making sound management recommendations. Thus, each of the decisions made in generating SDMs should be reported and evaluated to ensure conclusions and policies are based on the biology and ecology of the species being modeled.

  15. Predicting the fate of biodiversity using species' distribution models: enhancing model comparability and repeatability.

    Science.gov (United States)

    Rodríguez-Castañeda, Genoveva; Hof, Anouschka R; Jansson, Roland; Harding, Larisa E

    2012-01-01

    Species distribution modeling (SDM) is an increasingly important tool to predict the geographic distribution of species. Even though many problems associated with this method have been highlighted and solutions have been proposed, little has been done to increase comparability among studies. We reviewed recent publications applying SDMs and found that seventy nine percent failed to report methods that ensure comparability among studies, such as disclosing the maximum probability range produced by the models and reporting on the number of species occurrences used. We modeled six species of Falco from northern Europe and demonstrate that model results are altered by (1) spatial bias in species' occurrence data, (2) differences in the geographic extent of the environmental data, and (3) the effects of transformation of model output to presence/absence data when applying thresholds. Depending on the modeling decisions, forecasts of the future geographic distribution of Falco ranged from range contraction in 80% of the species to no net loss in any species, with the best model predicting no net loss of habitat in Northern Europe. The fact that predictions of range changes in response to climate change in published studies may be influenced by decisions in the modeling process seriously hampers the possibility of making sound management recommendations. Thus, each of the decisions made in generating SDMs should be reported and evaluated to ensure conclusions and policies are based on the biology and ecology of the species being modeled.

  16. A comparative study of aerosol deposition in different lung models.

    Science.gov (United States)

    Yu, C P; Diu, C K

    1982-01-01

    Theoretical calculations are made on total and regional deposition of inhaled particles in the human respiratory system based upon various current lung models. It is found that although total deposition does not vary appreciably from model to model, considerably large differences are present in regional deposition. Deposition profiles along the airways from different models also show very different patterns. These differences can be explained in terms of airway dimensions and the number of structures in different models. Extension to explain intersubject variability is also made.

  17. Lithium-ion battery models: a comparative study and a model-based powerline communication

    Science.gov (United States)

    Saidani, Fida; Hutter, Franz X.; Scurtu, Rares-George; Braunwarth, Wolfgang; Burghartz, Joachim N.

    2017-09-01

    In this work, various Lithium-ion (Li-ion) battery models are evaluated according to their accuracy, complexity and physical interpretability. An initial classification into physical, empirical and abstract models is introduced. Also known as white, black and grey boxes, respectively, the nature and characteristics of these model types are compared. Since the Li-ion battery cell is a thermo-electro-chemical system, the models are either in the thermal or in the electrochemical state-space. Physical models attempt to capture key features of the physical process inside the cell. Empirical models describe the system with empirical parameters offering poor analytical, whereas abstract models provide an alternative representation. In addition, a model selection guideline is proposed based on applications and design requirements. A complex model with a detailed analytical insight is of use for battery designers but impractical for real-time applications and in situ diagnosis. In automotive applications, an abstract model reproducing the battery behavior in an equivalent but more practical form, mainly as an equivalent circuit diagram, is recommended for the purpose of battery management. As a general rule, a trade-off should be reached between the high fidelity and the computational feasibility. Especially if the model is embedded in a real-time monitoring unit such as a microprocessor or a FPGA, the calculation time and memory requirements rise dramatically with a higher number of parameters. Moreover, examples of equivalent circuit models of Lithium-ion batteries are covered. Equivalent circuit topologies are introduced and compared according to the previously introduced criteria. An experimental sequence to model a 20 Ah cell is presented and the results are used for the purposes of powerline communication.

  18. Lithium-ion battery models: a comparative study and a model-based powerline communication

    Directory of Open Access Journals (Sweden)

    F. Saidani

    2017-09-01

    Full Text Available In this work, various Lithium-ion (Li-ion battery models are evaluated according to their accuracy, complexity and physical interpretability. An initial classification into physical, empirical and abstract models is introduced. Also known as white, black and grey boxes, respectively, the nature and characteristics of these model types are compared. Since the Li-ion battery cell is a thermo-electro-chemical system, the models are either in the thermal or in the electrochemical state-space. Physical models attempt to capture key features of the physical process inside the cell. Empirical models describe the system with empirical parameters offering poor analytical, whereas abstract models provide an alternative representation. In addition, a model selection guideline is proposed based on applications and design requirements. A complex model with a detailed analytical insight is of use for battery designers but impractical for real-time applications and in situ diagnosis. In automotive applications, an abstract model reproducing the battery behavior in an equivalent but more practical form, mainly as an equivalent circuit diagram, is recommended for the purpose of battery management. As a general rule, a trade-off should be reached between the high fidelity and the computational feasibility. Especially if the model is embedded in a real-time monitoring unit such as a microprocessor or a FPGA, the calculation time and memory requirements rise dramatically with a higher number of parameters. Moreover, examples of equivalent circuit models of Lithium-ion batteries are covered. Equivalent circuit topologies are introduced and compared according to the previously introduced criteria. An experimental sequence to model a 20 Ah cell is presented and the results are used for the purposes of powerline communication.

  19. Computational Models for Analysis of Illicit Activities

    DEFF Research Database (Denmark)

    Nizamani, Sarwat

    Numerous illicit activities happen in our society, which, from time to time affect the population by harming individuals directly or indirectly. Researchers from different disciplines have contributed to developing strategies to analyze such activities, in order to help law enforcement agents....... These models include a model for analyzing evolution of terrorist networks; a text classification model for detecting suspicious text and identification of suspected authors of anonymous emails; and a semantic analysis model for news reports, which may help analyze the illicit activities in certain area...... with location and temporal information. For the network evolution, the hierarchical agglomerative clustering approach has been applied to terrorist networks as case studies. The networks' evolutions show that how individual actors who are initially isolated from each other are converted in small groups, which...

  20. Active Gel Model of Amoeboid Cell Motility

    CERN Document Server

    Callan-Jones, A C

    2013-01-01

    We develop a model of amoeboid cell motility based on active gel theory. Modeling the motile apparatus of a eukaryotic cell as a confined layer of finite length of poroelastic active gel permeated by a solvent, we first show that, due to active stress and gel turnover, an initially static and homogeneous layer can undergo a contractile-type instability to a polarized moving state in which the rear is enriched in gel polymer. This agrees qualitatively with motile cells containing an actomyosin-rich uropod at their rear. We find that the gel layer settles into a steadily moving, inhomogeneous state at long times, sustained by a balance between contractility and filament turnover. In addition, our model predicts an optimal value of the gel-susbstrate adhesion leading to maximum layer speed, in agreement with cell motility assays. The model may be relevant to motility of cells translocating in complex, confining environments that can be mimicked experimentally by cell migration through microchannels.

  1. Accuracy of laser-scanned models compared to plaster models and cone-beam computed tomography.

    Science.gov (United States)

    Kim, Jooseong; Heo, Giseon; Lagravère, Manuel O

    2014-05-01

    To compare the accuracy of measurements obtained from the three-dimensional (3D) laser scans to those taken from the cone-beam computed tomography (CBCT) scans and those obtained from plaster models. Eighteen different measurements, encompassing mesiodistal width of teeth and both maxillary and mandibular arch length and width, were selected using various landmarks. CBCT scans and plaster models were prepared from 60 patients. Plaster models were scanned using the Ortho Insight 3D laser scanner, and the selected landmarks were measured using its software. CBCT scans were imported and analyzed using the Avizo software, and the 26 landmarks corresponding to the selected measurements were located and recorded. The plaster models were also measured using a digital caliper. Descriptive statistics and intraclass correlation coefficient (ICC) were used to analyze the data. The ICC result showed that the values obtained by the three different methods were highly correlated in all measurements, all having correlations>0.808. When checking the differences between values and methods, the largest mean difference found was 0.59 mm±0.38 mm. In conclusion, plaster models, CBCT models, and laser-scanned models are three different diagnostic records, each with its own advantages and disadvantages. The present results showed that the laser-scanned models are highly accurate to plaster models and CBCT scans. This gives general clinicians an alternative to take into consideration the advantages of laser-scanned models over plaster models and CBCT reconstructions.

  2. Comparative performance of high-fidelity training models for flexible ureteroscopy: Are all models effective?

    Directory of Open Access Journals (Sweden)

    Shashikant Mishra

    2011-01-01

    Full Text Available Objective: We performed a comparative study of high-fidelity training models for flexible ureteroscopy (URS. Our objective was to determine whether high-fidelity non-virtual reality (VR models are as effective as the VR model in teaching flexible URS skills. Materials and Methods: Twenty-one trained urologists without clinical experience of flexible URS underwent dry lab simulation practice. After a warm-up period of 2 h, tasks were performed on a high-fidelity non-VR (Uro-scopic Trainer TM ; Endo-Urologie-Modell TM and a high-fidelity VR model (URO Mentor TM . The participants were divided equally into three batches with rotation on each of the three stations for 30 min. Performance of the trainees was evaluated by an expert ureteroscopist using pass rating and global rating score (GRS. The participants rated a face validity questionnaire at the end of each session. Results: The GRS improved statistically at evaluation performed after second rotation (P<0.001 for batches 1, 2 and 3. Pass ratings also improved significantly for all training models when the third and first rotations were compared (P<0.05. The batch that was trained on the VR-based model had more improvement on pass ratings on second rotation but could not achieve statistical significance. Most of the realistic domains were higher for a VR model as compared with the non-VR model, except the realism of the flexible endoscope. Conclusions: All the models used for training flexible URS were effective in increasing the GRS and pass ratings irrespective of the VR status.

  3. Comparative Election Forecasting: Further Insights from Synthetic Models

    OpenAIRE

    Michael S. Lewis-Beck; Dassonneville, Ruth

    2015-01-01

    As an enterprise, election forecasting has spread and grown. Initial work began in the 1980s in the United States, eventually travelling to Western Europe, where it finds a current outlet in the most of the region’s democracies. However, that work has been confined to traditional approaches – statistical modeling or poll-watching. We import a new approach, which we call synthetic modeling. These forecasts come from hybrid models blending structural knowledge with contemporary p...

  4. Modeling Atmospheric Activity of Cool Stars

    Science.gov (United States)

    Schrijver, C. J.

    2003-10-01

    This review discusses a set of simple models for cool-star activity with which we compute (1) photospheric field patterns on stars of different activity levels, (2) the associated outer-atmospheric field configurations, and (3) the soft X-ray emission that is expected to result from the ensemble of loop atmospheres in the coronae of these stars. The model is based on empirically-determined properties of solar activity. It allows us to extrapolate to stars of significantly higher and lower activity than seen on the present-day Sun through its cycle. With it, we can, for example, gain insight into stellar field patterns (including a possible formation mechanism for polar starspots), as well as in the properties of coronal heating (helpful in the identification of the quiescent coronal heating mechanism). Lacking comprehensive theoretical understanding, the model's reliance on empirical solar data means that the multitude of processes involved are approximated to be independent of rotation rate, activity level, and fundamental stellar parameters, or -- where unavoidably necessary -- assumed to simply scale with activity. An evaluation of the most important processes involved guides a discussion of the limits of the model, of the limitations in our knowledge, and of future needs. "I propose to adopt such rules as will ensure the testability of scientific statements; which is to say, their falsifiability." Karl Popper (1902-1994)

  5. Mental Models about Seismic Effects: Students' Profile Based Comparative Analysis

    Science.gov (United States)

    Moutinho, Sara; Moura, Rui; Vasconcelos, Clara

    2016-01-01

    Nowadays, meaningful learning takes a central role in science education and is based in mental models that allow the representation of the real world by individuals. Thus, it is essential to analyse the student's mental models by promoting an easier reconstruction of scientific knowledge, by allowing them to become consistent with the curricular…

  6. Criteria for comparing economic impact models of tourism

    NARCIS (Netherlands)

    Klijs, J.; Heijman, W.J.M.; Korteweg Maris, D.; Bryon, J.

    2012-01-01

    There are substantial differences between models of the economic impacts of tourism. Not only do the nature and precision of results vary, but data demands, complexity and underlying assumptions also differ. Often, it is not clear whether the models chosen are appropriate for the specific situation

  7. Criteria for comparing economic impact models of tourism

    NARCIS (Netherlands)

    Klijs, J.; Heijman, W.J.M.; Korteweg Maris, D.; Bryon, J.

    2012-01-01

    There are substantial differences between models of the economic impacts of tourism. Not only do the nature and precision of results vary, but data demands, complexity and underlying assumptions also differ. Often, it is not clear whether the models chosen are appropriate for the specific situation

  8. COMPARATIVE EVALUATION OF COMMERCIAL AND SEWAGE SLUDGE BASED ACTIVATED CARBONS FOR THE REMOVAL OF TEXTILE DYES FROM AQUEOUS SOLUTIONS

    Directory of Open Access Journals (Sweden)

    S. Sreedhar Reddy, B. Kotaiah

    2006-10-01

    Full Text Available The sorption of dyes from aqueous solutions on to sludge-based activated carbon have been studied and compared with commercial activated carbon. Adsorption parameters for the Langmuir and Freundlich isotherms were determined and the effects of effluent pH, adsorbent dosage, contact time and initial dye concentration were studied. A pseudo-second order kinetic model has been proposed to correlate the experimental data.

  9. A comparative DFT study of the catalytic activity of the 3d transition metal sulphides surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Gomez-Balderas, R. (Depto de F& amp; #237; s. y Qu& amp; #237; m. Te& amp; #243; rica. Edif. B, Fac. de Qu& amp; #237; mica, UNAM ); Oviedo-Roa, R (Instituto Mexicano del Petroleo); Martinez-Magadan, J M.(Instituto Mexicano del Petroleo); Amador, C. (Depto de F& amp; #237; s. y Qu& amp; #237; m. Te& amp; #243; rica. Edif. B, Fac. de Qu& amp; #237; mica, UNAM ); Dixon, David A.(BATTELLE (PACIFIC NW LAB))

    2002-10-10

    The catalytic activity of the first transition metal series sulphides for hydrodesulfurization (HDS) reactions exhibits a particular behaviour when analysed as a function of the metal position in the Periodic Table. This work reports a comparative study of the electronic structure of the bulk and of the (0 0 1) metal surface (assumed to be the reactive surface) for the Sc-Zn monosulphides. The systems were modeled using the NiAs prototype crystal structure for the bulk and by applying the supercell model with seven atomic layers for (0 0 1) surfaces. The electronic structure of closed-packed solids code based on the density-functional theory and adopting the muffin-tin approximation to the potential was employed in the calculations of the electronic properties. For the Co and Ni sulphides, the density of states (DOS) variations between the metal atom present in the bulk and the ones exposed at the surface show that at the surface, there exists a higher DOS in the occupied states region just below the Fermi level. This feature might indicate a good performance of these two metal sulphides substrates in the HDS reactions favouring a donation, back-donation mechanism. In contrast, the DOS at the surface of Mn is increased in the unoccupied states region, just above the Fermi level. This suggests the possibility of a strong interaction with charge dontating sulphur adsorbate atoms poisoning the active substrate surface.

  10. The cost-utility of open prostatectomy compared with active surveillance in early localised prostate cancer

    Science.gov (United States)

    2014-01-01

    Background There is an on-going debate about whether to perform surgery on early stage localised prostate cancer and risk the common long term side effects such as urinary incontinence and erectile dysfunction. Alternatively these patients could be closely monitored and treated only in case of disease progression (active surveillance). The aim of this paper is to develop a decision-analytic model comparing the cost-utility of active surveillance (AS) and radical prostatectomy (PE) for a cohort of 65 year old men with newly diagnosed low risk prostate cancer. Methods A Markov model comparing PE and AS over a lifetime horizon was programmed in TreeAge from a German societal perspective. Comparative disease specific mortality was obtained from the Scandinavian Prostate Cancer Group trial. Direct costs were identified via national treatment guidelines and expert interviews covering in-patient, out-patient, medication, aids and remedies as well as out of pocket payments. Utility values were used as factor weights for age specific quality of life values of the German population. Uncertainty was assessed deterministically and probabilistically. Results With quality adjustment, AS was the dominant strategy compared with initial treatment. In the base case, it was associated with an additional 0.04 quality adjusted life years (7.60 QALYs vs. 7.56 QALYs) and a cost reduction of €6,883 per patient (2011 prices). Considering only life-years gained, PE was more effective with an incremental cost-effectiveness ratio of €96,420/life year gained. Sensitivity analysis showed that the probability of developing metastases under AS and utility weights under AS are a major sources of uncertainty. A Monte Carlo simulation revealed that AS was more likely to be cost-effective even under very high willingness to pay thresholds. Conclusion AS is likely to be a cost-saving treatment strategy for some patients with early stage localised prostate cancer. However, cost-effectiveness is

  11. How realistic are flat-ramp-flat fault kinematic models? Comparing mechanical and kinematic models

    Science.gov (United States)

    Cruz, L.; Nevitt, J. M.; Hilley, G. E.; Seixas, G.

    2015-12-01

    Rock within the upper crust appears to deform according to elasto-plastic constitutive rules, but structural geologists often employ kinematic descriptions that prescribe particle motions irrespective of these physical properties. In this contribution, we examine the range of constitutive properties that are approximately implied by kinematic models by comparing predicted deformations between mechanical and kinematic models for identical fault geometric configurations. Specifically, we use the ABAQUS finite-element package to model a fault-bend-fold geometry using an elasto-plastic constitutive rule (the elastic component is linear and the plastic failure occurs according to a Mohr-Coulomb failure criterion). We varied physical properties in the mechanical model (i.e., Young's modulus, Poisson ratio, cohesion yield strength, internal friction angle, sliding friction angle) to determine the impact of each on the observed deformations, which were then compared to predictions of kinematic models parameterized with identical geometries. We found that a limited sub-set of physical properties were required to produce deformations that were similar to those predicted by the kinematic models. Specifically, mechanical models with low cohesion are required to allow the kink at the bottom of the flat-ramp geometry to remain stationary over time. Additionally, deformations produced by steep ramp geometries (30 degrees) are difficult to reconcile between the two types of models, while lower slope gradients better conform to the geometric assumptions. These physical properties may fall within the range of those observed in laboratory experiments, suggesting that particle motions predicted by kinematic models may provide an approximate representation of those produced by a physically consistent model under some circumstances.

  12. Lattice Boltzmann modeling of directional wetting: Comparing simulations to experiments

    NARCIS (Netherlands)

    Jansen, H.P.; Sotthewes, K.; Swigchem, van J.; Zandvliet, H.J.W.; Kooij, E.S.

    2013-01-01

    Lattice Boltzmann Modeling (LBM) simulations were performed on the dynamic behavior of liquid droplets on chemically striped patterned surfaces, ultimately with the aim to develop a predictive tool enabling reliable design of future experiments. The simulations accurately mimic experimental results,

  13. Comparative model accuracy of a data-fitted generalized Aw-Rascle-Zhang model

    CERN Document Server

    Fan, Shimao; Seibold, Benjamin

    2013-01-01

    The Aw-Rascle-Zhang (ARZ) model can be interpreted as a generalization of the Lighthill-Whitham-Richards (LWR) model, possessing a family of fundamental diagram curves, each of which represents a class of drivers with a different empty road velocity. A weakness of this approach is that different drivers possess vastly different densities at which traffic flow stagnates. This drawback can be overcome by modifying the pressure relation in the ARZ model, leading to the generalized Aw-Rascle-Zhang (GARZ) model. We present an approach to determine the parameter functions of the GARZ model from fundamental diagram measurement data. The predictive accuracy of the resulting data-fitted GARZ model is compared to other traffic models by means of a three-detector test setup, employing two types of data: vehicle trajectory data, and sensor data. This work also considers the extension of the ARZ and the GARZ models to models with a relaxation term, and conducts an investigation of the optimal relaxation time.

  14. A COMPARATIVE STUDY ON THE ACTIVITY OF ALANIN-AMINOTRANSFERASE IN HYPOPHTHALMICHTHYS MOLITRIX AND ARISTICHTHYS NOBILIS

    Directory of Open Access Journals (Sweden)

    Gabriela Vasile

    2006-08-01

    Full Text Available The present paper represents a comparative study on the activity of one aminotransferase - alaninaminotransferase, in the digestive tube of Hypophthalmichthys molitrix (silver carp and Aristichthys nobilis (bighead carp. The enzymatic activity has been determined colorimetrically, with 2, 4 - dinitrophenyl hydrazine, the results obtained being expressed as UE / g / min. It was observed that, comparatively with the alanin-aminotransferase activity recorded in silver carp, in the case of bighead carp, the values recorded are much lower.

  15. The structure of common fears: comparing three different models.

    Science.gov (United States)

    de Jongh, Ad; Oosterink, Floor M D; Kieffer, Jacobien M; Hoogstraten, Johan; Aartman, Irene H A

    2011-01-01

    Previous studies showed discrepant findings regarding the factor structure of common fears. The purpose of the present study was to expand on these findings and contribute to the development of a descriptive framework for a fear classification. Using data from the Dutch general population (n = 961; 50.9% women), an exploratory factor analysis was performed to delineate the multidimensional structure of 11 common fears previously used in a factor analytic study by Fredrikson, Annas, Fischer, and Wik (1996). An independent sample (n = 998; 48.3% women) was used to confirm the newly derived model by means of confirmatory factor analysis. In addition, the model was tested against the DSM-IV-TR model and a model found earlier by Fredrikson et al. (1996). Although support was found for a 3-factor solution consisting of a blood-injection-injury factor, a situational-animal factor, and a height-related factor, confirmatory factor analysis showed that this 3-factor model and the DSM-IV-TR 4-factor model fitted the data equally well. The findings suggest that the structure of subclinical fears can be inferred from the DSM classification of phobia subtypes and that fears and phobias are two observable manifestations of a fear response along a continuum.

  16. A Comparative Study of Power Consumption Models for CPA Attack

    Directory of Open Access Journals (Sweden)

    Hassen Mestiri

    2013-03-01

    Full Text Available Power analysis attacks are types of side channel attacks that are based on analyzing the power consumption of the cryptographic devices. Correlation power analysis is a powerful and efficient cryptanalytic technique. It exploits the linear relation between the predicted power consumption and the real power consumption of cryptographic devices in order to recover the correct key. The predicted power consumption is determined by using the appropriate consumption model. Until now, only a few models have been proposed and used.In this paper, we describe the process to conduct the CPA attack against AES on SASEBO-GII board. We present a comparison between the Hamming Distance model and the Switching Distance model, in terms of number of power traces needed to recover the correct key using these models. The global successful rate achieves 100% at 11100 power traces. The power traces needed to recover the correct key have been decreased by 12.6% using a CPA attack with Switching Distance model.

  17. Comparative Analysis of Two Models of the Strouma River Ecosystem

    Directory of Open Access Journals (Sweden)

    Mitko Petrov

    2008-04-01

    Full Text Available A modified method of regression analysis for modelling of the water quality of river ecosystems is offered. The method is distinguished from the conventional regression analysis of that the factors included in the regression dependence are time functions. Two type functions are tested: polynomial and periodical. The investigations show better results the periodical functions give. In addition, a model for analysis of river quality has been developed, which is a modified method of the time series analysis. The model has been applied for an assessment of water pollution of the Strouma river. An assessment for adequately of the obtained model of the statistical criteria - correlation coefficient, Fisher function and relative error is developed and it shows that the models are adequate and they can be used for modelling of the water pollution on these indexes of the Strouma river. The analysis of the river pollution shows that there is not a materially increase of the anthropogenic impact of the Strouma river in the Bulgarian part for the period from 2001 to 2004.

  18. Comparative flood damage model assessment: towards a European approach

    Directory of Open Access Journals (Sweden)

    B. Jongman

    2012-12-01

    Full Text Available There is a wide variety of flood damage models in use internationally, differing substantially in their approaches and economic estimates. Since these models are being used more and more as a basis for investment and planning decisions on an increasingly large scale, there is a need to reduce the uncertainties involved and develop a harmonised European approach, in particular with respect to the EU Flood Risks Directive. In this paper we present a qualitative and quantitative assessment of seven flood damage models, using two case studies of past flood events in Germany and the United Kingdom. The qualitative analysis shows that modelling approaches vary strongly, and that current methodologies for estimating infrastructural damage are not as well developed as methodologies for the estimation of damage to buildings. The quantitative results show that the model outcomes are very sensitive to uncertainty in both vulnerability (i.e. depth–damage functions and exposure (i.e. asset values, whereby the first has a larger effect than the latter. We conclude that care needs to be taken when using aggregated land use data for flood risk assessment, and that it is essential to adjust asset values to the regional economic situation and property characteristics. We call for the development of a flexible but consistent European framework that applies best practice from existing models while providing room for including necessary regional adjustments.

  19. Comparative study of hypoglycemic and antibacterial activity of organic extracts of four Bangladeshi plants

    Institute of Scientific and Technical Information of China (English)

    Mohammad Shah Hafez Kabir; Shabbir Ahmad; Md. Sofi Mahamoud; Nishan Chakrabarty; Md.Akramul Hoque; Mohammed Munawar Hossain; Md.Nazim Uddin Chy; Mohammed Shoibe

    2016-01-01

    Objective:To examine hypoglycemic and antibacterial activity against some Gram-positive and Gram-negative bacteria of organic extracts of four Bangladeshi plants. Methods:Anin vivo hypoglycemic effect on mice model was used to check the hypoglycemic effect of four Bangladeshi herbal organic extractsviz., roots ofCurculigo recurvata W. T. Aiton (Satipata) (C. recurvata), leaf ofAmorphophallus bulbiferRoxb. (Olkachu) (A. bulbifer), whole plant ofThunbergia grandiflora Roxb. (Nillata) (T. grandiflora) and leaf ofSteudnera colocasiifolia K. Koch (Yunnan) (S. colocasiifolia) using glibenclamide as a positive control and water as a negative control. They were also tested for antibacterial activity on three Gram-positive and four Gram-negative bacteria by disk diffusion method.C. recurvata,A. bulbifer andT. grandiflora were extracted with methanol andS. colocasiifolia was extracted with ethanol. Results:Among all the plant extract, only ethanol extract ofS. colocasiifolia leaves at 800 mg/kg dose significantly (P Conclusions: Through our study, it was found thatS. colocasiifolia could be considered as very promising and beneficial hypoglycemic agent. AlthoughC. recurvata andS. colocasiifolia showed comparable high antibacterial activity, further studies should be needed to develop new antibacterial agent from them.S. colocasiifolia may be a potential source for the development of new oral hypoglycemic agent.

  20. Comparative evaluation of adsorption kinetics of diclofenac and isoproturon by activated carbon.

    Science.gov (United States)

    Torrellas, Silvia A; Rodriguez, Araceli R; Escudero, Gabriel O; Martín, José María G; Rodriguez, Juan G

    2015-01-01

    Adsorption mechanism of diclofenac and isoproturon onto activated carbon has been proposed using Langmuir and Freundlich isotherms. Adsorption capacity and optimum adsorption isotherms were predicted by nonlinear regression method. Different kinetic equations, pseudo-first-order, pseudo-second-order, intraparticle diffusion model and Bangham kinetic model, were applied to study the adsorption kinetics of emerging contaminants on activated carbon in two aqueous matrices.

  1. Comparative Study between Two Schemes of Active-Control-Based Mechatronic Inerter

    Directory of Open Access Journals (Sweden)

    He Lingduo

    2017-01-01

    Full Text Available Based on force-current analogy and velocity-voltage analogy in the theory of electromechanical analogy, the inerter is a device that corresponded to the capacitor completely where conquers the nature restriction of mass, what’s more, it is significant to improve the ratio of the inerter’s inertance to its mass for mechanical networks synthesis. And according to the principle of active-control-based mechatronic inerter, we present two implementation schemes. One was based on linear motor, and the other was based on the ball screw and rotary motor. We introduced the implementation methods and established theoretical model of the two schemes, then compared the ratio of the inerter’s inertance to its mass for the two schemes. Finally, we consider the scheme is better which was based on the ball screw and rotary motor.

  2. Comparing artificial neural networks, general linear models and support vector machines in building predictive models for small interfering RNAs.

    Directory of Open Access Journals (Sweden)

    Kyle A McQuisten

    Full Text Available BACKGROUND: Exogenous short interfering RNAs (siRNAs induce a gene knockdown effect in cells by interacting with naturally occurring RNA processing machinery. However not all siRNAs induce this effect equally. Several heterogeneous kinds of machine learning techniques and feature sets have been applied to modeling siRNAs and their abilities to induce knockdown. There is some growing agreement to which techniques produce maximally predictive models and yet there is little consensus for methods to compare among predictive models. Also, there are few comparative studies that address what the effect of choosing learning technique, feature set or cross validation approach has on finding and discriminating among predictive models. PRINCIPAL FINDINGS: Three learning techniques were used to develop predictive models for effective siRNA sequences including Artificial Neural Networks (ANNs, General Linear Models (GLMs and Support Vector Machines (SVMs. Five feature mapping methods were also used to generate models of siRNA activities. The 2 factors of learning technique and feature mapping were evaluated by complete 3x5 factorial ANOVA. Overall, both learning techniques and feature mapping contributed significantly to the observed variance in predictive models, but to differing degrees for precision and accuracy as well as across different kinds and levels of model cross-validation. CONCLUSIONS: The methods presented here provide a robust statistical framework to compare among models developed under distinct learning techniques and feature sets for siRNAs. Further comparisons among current or future modeling approaches should apply these or other suitable statistically equivalent methods to critically evaluate the performance of proposed models. ANN and GLM techniques tend to be more sensitive to the inclusion of noisy features, but the SVM technique is more robust under large numbers of features for measures of model precision and accuracy. Features

  3. COMPARING FINANCIAL DISTRESS PREDICTION MODELS BEFORE AND DURING RECESSION

    Directory of Open Access Journals (Sweden)

    Nataša Šarlija

    2011-02-01

    Full Text Available The purpose of this paper is to design three separate financial distress prediction models that will track the changes in a relative importance of financial ratios throughout three consecutive years. The models were based on the financial data from 2000 privately-owned small and medium-sized enterprises in Croatia from 2006 to 2009, and developed by means of logistic regression. Macroeconomic conditions as well as market dynamic have been changed over the mentioned period. Financial ratios that were less important in one period become more important in the next period. Composition of model starting in 2006 has been changed in the next years. It tells us what financial ratios are more important during the time of economic downturn. Besides, it helps us to understand behavior of small and medium-sized enterprises in the period of prerecession and in the period of recession.

  4. The activity model of legal psychologist

    Directory of Open Access Journals (Sweden)

    N.V. Bogdanovich,

    2014-08-01

    Full Text Available We propose an activity model of legal psychologist work. As a basis for the construction of the system of legal psychologist activity, we use trajectory of teenager living in the legal field. As the main activities within their respective specializations, we highlighted prevention, maintenance and rehabilitation. We define the main activities necessary for the development within the FGOSIII specialization 050407 “Pedagogy and Psychology of deviant behavior”: general and pathopsychologic diagnostics, development activity and psychological education, psycho-correction, psychological counseling. Accordingly, we define the types of psychological practices. We highlight the motivational and integrative practice (teaching introductory and trainee. We propose a system of training modules, ensuring the formation of the necessary competencies. The modules feature is their focus on practice (the association of training courses with the main types of psychological practice.

  5. Comparing Multiple Discrepancies Theory to Affective Models of Subjective Wellbeing

    Science.gov (United States)

    Blore, Jed D.; Stokes, Mark A.; Mellor, David; Firth, Lucy; Cummins, Robert A.

    2011-01-01

    The Subjective Wellbeing (SWB) literature is replete with competing theories detailing the mechanisms underlying the construction and maintenance of SWB. The current study aimed to compare and contrast two of these approaches: multiple discrepancies theory (MDT) and an affective-cognitive theory of SWB. MDT posits SWB to be the result of perceived…

  6. Comparative pharmacodynamic modeling of desflurane, sevoflurane and isoflurane.

    NARCIS (Netherlands)

    Kreuer, S.; Bruhn, J.; Wilhelm, W.; Grundmann, U.; Rensing, H.; Ziegeler, S.

    2009-01-01

    BACKGROUND: We compared dose-response curves of the hypnotic effects of desflurane, sevoflurane and isoflurane. In addition, we analyzed the k(e0) values of the different anesthetics. The EEG parameters Bispectral index (BIS, Aspect Medical Systems, Natick, MA, version XP) and Narcotrend index (Moni

  7. Maternal inflammation during late pregnancy is lower in physically active compared with inactive obese women.

    Science.gov (United States)

    Tinius, Rachel A; Cahill, Alison G; Strand, Eric A; Cade, W Todd

    2016-02-01

    The primary purpose of this study was to compare maternal plasma inflammation between physically active and inactive obese women during late pregnancy. The secondary purpose was to examine the relationships between maternal plasma inflammation and lipid metabolism and maternal and neonatal metabolic health in these women. A cross-sectional, observational study design was performed in 16 obese-inactive (OBI; means ± SD; age, 25.0 ± 4.8 years; prepregnancy body mass index (BMI), 36.3 ± 4.3 kg/m(2); body fat percentage in late gestation, 37.7% ± 3.5%) and 16 obese-active (OBA; age, 28.9 ± 4.8 years; prepregnancy BMI, 34.0 ± 3.7 kg/m(2); body fat in late gestation, 36.6% ± 3.8%) women during the third trimester of pregnancy. Maternal plasma inflammation (C -reactive protein (CRP)) and insulin resistance (Homeostatic Model Assessment-Insulin Resistance) were measured at rest. Plasma lipid concentration and metabolism (lipid oxidation and lipolysis) were measured at rest, during a 30-min bout of low-intensity (40% peak oxygen uptake) exercise, and during a resting recovery period using indirect calorimetry. Umbilical cord blood was collected for measurement of neonatal plasma insulin resistance, inflammation, and lipid concentration. Neonatal body composition was measured via air displacement plethysmography. Maternal plasma CRP concentration was significantly higher in OBI compared with OBA women (9.1 ± 4.0 mg/L vs. 6.3 ± 2.5 mg/L, p = 0.02). Maternal plasma CRP concentration was significantly associated with maternal lipolysis (r = 0.43, p = 0.02), baseline lipid oxidation rate (r = 0.39, p = 0.03), and baseline plasma free fatty acid concentration (r = 0.36, p = 0.04). In conclusion, maternal physical activity may reduce inflammation during pregnancy in obese women. Maternal lipid metabolism is related to systemic inflammation.

  8. Comparative homology modeling of human rhodopsin with several ...

    African Journals Online (AJOL)

    Yomi

    2012-01-05

    Jan 5, 2012 ... humble effort has been made to identify and remove the loopholes in the existing structure (1EDS) and model the 3D structure ... as seen in the cryo-electron microscopy studies, with the ... cannot be obtained or dissolved in large enough ... of non-bonded interaction between different atom types was done.

  9. Nature of Science and Models: Comparing Portuguese Prospective Teachers' Views

    Science.gov (United States)

    Torres, Joana; Vasconcelos, Clara

    2015-01-01

    Despite the relevance of nature of science and scientific models in science education, studies reveal that students do not possess adequate views regarding these topics. Bearing in mind that both teachers' views and knowledge strongly influence students' educational experiences, the main scope of this study was to evaluate Portuguese prospective…

  10. Comparing State SAT Scores Using a Mixture Modeling Approach

    Science.gov (United States)

    Kim, YoungKoung Rachel

    2009-01-01

    Presented at the national conference for AERA (American Educational Research Association) in April 2009. The large variability of SAT taker population across states makes state-by-state comparisons of the SAT scores challenging. Using a mixture modeling approach, therefore, the current study presents a method of identifying subpopulations in terms…

  11. Nature of Science and Models: Comparing Portuguese Prospective Teachers' Views

    Science.gov (United States)

    Torres, Joana; Vasconcelos, Clara

    2015-01-01

    Despite the relevance of nature of science and scientific models in science education, studies reveal that students do not possess adequate views regarding these topics. Bearing in mind that both teachers' views and knowledge strongly influence students' educational experiences, the main scope of this study was to evaluate Portuguese prospective…

  12. Comparing the performance of species distribution models of

    NARCIS (Netherlands)

    Valle , M.; van Katwijk, M.M.; de Jong, D.J.; Bouma, T.; Schipper, A.M.; Chust, G.; Benito, B.M.; Garmendia, J.M.; Borja, A.

    2013-01-01

    Intertidal seagrasses show high variability in their extent and location, with local extinctions and (re-)colonizations being inherent in their population dynamics. Suitable habitats are identified usually using Species Distribution Models (SDM), based upon the overall distribution of the species;

  13. Grey forecasting model for active vibration control systems

    Science.gov (United States)

    Lihua, Zou; Suliang, Dai; Butterworth, John; Ma, Xing; Dong, Bo; Liu, Aiping

    2009-05-01

    Based on the grey theory, a GM(1,1) forecasting model and an optimal GM(1,1) forecasting model are developed and assessed for use in active vibration control systems for earthquake response mitigation. After deriving equations for forecasting the control state vector, design procedures for an optimal active control method are proposed. Features of the resulting vibration control and the influence on it of time-delay based on different sampling intervals of seismic ground motion are analysed. The numerical results show that the forecasting models based on the grey theory are reliable and practical in structural vibration control fields. Compared with the grey forecasting model, the optimal forecasting model is more efficient in reducing the influences of time-delay and disturbance errors.

  14. Using nonlinear models in fMRI data analysis: model selection and activation detection.

    Science.gov (United States)

    Deneux, Thomas; Faugeras, Olivier

    2006-10-01

    There is an increasing interest in using physiologically plausible models in fMRI analysis. These models do raise new mathematical problems in terms of parameter estimation and interpretation of the measured data. In this paper, we show how to use physiological models to map and analyze brain activity from fMRI data. We describe a maximum likelihood parameter estimation algorithm and a statistical test that allow the following two actions: selecting the most statistically significant hemodynamic model for the measured data and deriving activation maps based on such model. Furthermore, as parameter estimation may leave much incertitude on the exact values of parameters, model identifiability characterization is a particular focus of our work. We applied these methods to different variations of the Balloon Model (Buxton, R.B., Wang, E.C., and Frank, L.R. 1998. Dynamics of blood flow and oxygenation changes during brain activation: the balloon model. Magn. Reson. Med. 39: 855-864; Buxton, R.B., Uludağ, K., Dubowitz, D.J., and Liu, T.T. 2004. Modelling the hemodynamic response to brain activation. NeuroImage 23: 220-233; Friston, K. J., Mechelli, A., Turner, R., and Price, C. J. 2000. Nonlinear responses in fMRI: the balloon model, volterra kernels, and other hemodynamics. NeuroImage 12: 466-477) in a visual perception checkerboard experiment. Our model selection proved that hemodynamic models better explain the BOLD response than linear convolution, in particular because they are able to capture some features like poststimulus undershoot or nonlinear effects. On the other hand, nonlinear and linear models are comparable when signals get noisier, which explains that activation maps obtained in both frameworks are comparable. The tools we have developed prove that statistical inference methods used in the framework of the General Linear Model might be generalized to nonlinear models.

  15. PATTERNS OF ACTIVITY IN A GLOBAL MODEL OF A SOLAR ACTIVE REGION

    Energy Technology Data Exchange (ETDEWEB)

    Bradshaw, S. J. [Department of Physics and Astronomy, Rice University, Houston, TX 77005 (United States); Viall, N. M., E-mail: stephen.bradshaw@rice.edu, E-mail: Nicholeen.M.Viall@nasa.gov [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States)

    2016-04-10

    In this work we investigate the global activity patterns predicted from a model active region heated by distributions of nanoflares that have a range of frequencies. What differs is the average frequency of the distributions. The activity patterns are manifested in time lag maps of narrow-band instrument channel pairs. We combine hydrodynamic and forward modeling codes with a magnetic field extrapolation to create a model active region and apply the time lag method to synthetic observations. Our aim is not to reproduce a particular set of observations in detail, but to recover some typical properties and patterns observed in active regions. Our key findings are the following. (1) Cooling dominates the time lag signature and the time lags between the channel pairs are generally consistent with observed values. (2) Shorter coronal loops in the core cool more quickly than longer loops at the periphery. (3) All channel pairs show zero time lag when the line of sight passes through coronal loop footpoints. (4) There is strong evidence that plasma must be re-energized on a timescale comparable to the cooling timescale to reproduce the observed coronal activity, but it is likely that a relatively broad spectrum of heating frequencies are operating across active regions. (5) Due to their highly dynamic nature, we find nanoflare trains produce zero time lags along entire flux tubes in our model active region that are seen between the same channel pairs in observed active regions.

  16. ON SKEW-NORMAL MODEL FOR ECONOMICALLY ACTIVE POPULATION

    Directory of Open Access Journals (Sweden)

    OLOSUNDE AKINLOLU A

    2011-04-01

    Full Text Available The literature related to skew-symmetric distribution have grown rapidly in recent years but at the moment no publication on its applications concerning the description of economically active data with this type of probability models. In this paper, we provided an extension to this skew-normal distribution, which is also part of the family of skewed class of normal but with additional shape parameters δ. Some properties of this distribution are presented and finally, we considered fitting it to economically active population data. The model exhibited a better behaviour when compared to normal and skew normal distributions.

  17. The Kolb Model Modified for Classroom Activities.

    Science.gov (United States)

    Svinicki, Marilla D.; Dixon, Nancy M.

    1987-01-01

    The experiential learning model of Kolb provides a framework for examining the selection of a broader range of classroom activities than is in current use. Experiential learning cycle, experiential learning as instructional design, and student as actor versus student as receiver are discussed. (MLW)

  18. The Seasons Explained by Refutational Modeling Activities

    Science.gov (United States)

    Frede, Valerie

    2008-01-01

    This article describes the principles and investigation of a small-group laboratory activity based on refutational modeling to teach the concept of seasons to preservice elementary teachers. The results show that these teachers improved significantly when they had to refute their initial misconceptions practically. (Contains 8 figures and 1 table.)

  19. Realistic Real World Contexts: Model Eliciting Activities

    Science.gov (United States)

    Doruk, Bekir Kürsat

    2016-01-01

    Researchers have proposed a variety of methods to make a connection between real life and mathematics so that it can be learned in a practical way and enable people to utilise mathematics in their daily lives. Model-eliciting activities (MEAs) were developed to fulfil this need and are very capable of serving this purpose. The reason MEAs are so…

  20. Estimating an Activity Driven Hidden Markov Model

    OpenAIRE

    Meyer, David A.; Shakeel, Asif

    2015-01-01

    We define a Hidden Markov Model (HMM) in which each hidden state has time-dependent $\\textit{activity levels}$ that drive transitions and emissions, and show how to estimate its parameters. Our construction is motivated by the problem of inferring human mobility on sub-daily time scales from, for example, mobile phone records.

  1. Comparative efficacies of antibiotics in a rat model of meningoencephalitis due to Listeria monocytogenes.

    Science.gov (United States)

    Michelet, C; Leib, S L; Bentue-Ferrer, D; Täuber, M G

    1999-07-01

    The antibacterial activities of amoxicillin-gentamicin, trovafloxacin, trimethoprim-sulfamethoxazole (TMP-SMX) and the combination of trovafloxacin with TMP-SMX were compared in a model of meningoencephalitis due to Listeria monocytogenes in infant rats. At 22 h after intracisternal infection, the cerebrospinal fluid was cultured to document meningitis, and the treatment was started. Treatment was instituted for 48 h, and efficacy was evaluated 24 h after administration of the last dose. All tested treatment regimens exhibited significant activities in brain, liver, and blood compared to infected rats receiving saline (P amoxicillin plus gentamicin was more active than all of the other regimens, and trovafloxacin was more active than TMP-SMX (bacterial titers of 4.1 +/- 0.5 log10 CFU/ml for amoxicillin-gentamicin, 5.0 +/- 0.4 log10 CFU/ml for trovafloxacin, and 5.8 +/- 0.5 log10 CFU/ml for TMP-SMX; P < 0.05). In liver, amoxicillin-gentamicin and trovafloxacin were similarly active (2.8 +/- 0.8 and 2.7 +/- 0.8 log10 CFU/ml, respectively) but more active than TMP-SMX (4.4 +/- 0. 6 log10 CFU/ml; P < 0.05). The combination of trovafloxacin with TMP-SMX did not alter the antibacterial effect in the brain, but it did reduce the effect of trovafloxacin in the liver. Amoxicillin-gentamicin was the most active therapy in this study, but the activity of trovafloxacin suggests that further studies with this drug for the treatment of Listeria infections may be warranted.

  2. Modelling spatial patterns of economic activity in the Netherlands

    CERN Document Server

    Yang, Jung-Hun; Frenken, Koen; Van Oort, Frank; Visser, Evert-Jan

    2012-01-01

    Understanding how spatial configurations of economic activity emerge is important when formulating spatial planning and economic policy. Not only micro-simulation and agent-based model such as UrbanSim, ILUMAS and SIMFIRMS, but also Simon's model of hierarchical concentration have widely applied, for this purpose. These models, however, have limitations with respect to simulating structural changes in spatial economic systems and the impact of proximity. The present paper proposes a model of firm development that is based on behavioural rules such as growth, closure, spin-off and relocation. An important aspect of the model is that locational preferences of firms are based on agglomeration advantages, accessibility of markets and congestion, allowing for a proper description of concentration and deconcentration tendencies. By comparing the outcomes of the proposed model with real world data, we will calibrate the parameters and assess how well the model predicts existing spatial configurations and decide. The...

  3. Modeling and Control of Active Suspensions for MDOF Vehicle

    Institute of Scientific and Technical Information of China (English)

    李克强; 郑四发; 杨殿阁; 连小珉; 永井正夫

    2003-01-01

    The conventional method for analyzing active suspension control for a vehicle is only to analyze aquarter or half car with a lower order degree-of freedom (DOF) model, but such models do not actually modelpractical applications. Accurate models of a suspension control system require a multi-degree-of-freedom(MDOF) vehicle model with a detailed model of the controller. An MDOF model was developed including theinfluence of factors such as the engine, the seats, and the passengers to describe vehicle motion using areduced order model of the controller designed by using the H∞ control method. The control systemperformance has been investigated by comparing the H∞ controller with a linear quadratic (LQ) controller.

  4. Antifibrotic activities of pirfenidone in animal models

    Directory of Open Access Journals (Sweden)

    L. Pan

    2011-06-01

    Full Text Available Pirfenidone is an orally active small molecule that has recently been evaluated in large clinical trials for the treatment of idiopathic pulmonary fibrosis, a fatal disease in which the uncontrolled deposition of extracellular matrix leads to progressive loss of lung function. This review describes the activity of pirfenidone in several well-characterised animal models of fibrosis in the lung, liver, heart and kidney. In these studies, treatment-related reductions in fibrosis are associated with modulation of cytokines and growth factors, with the most commonly reported effect being reduction of transforming growth factor-β. The consistent antifibrotic activity of pirfenidone in a broad array of animal models provides a strong preclinical rationale for the clinical characterisation of pirfenidone in pulmonary fibrosis and, potentially, other conditions with a significant fibrotic component.

  5. Comparative study and error analysis of digital elevation model interpolations

    Institute of Scientific and Technical Information of China (English)

    CHEN Ji-long; WU Wei; LIU Hong-bin

    2008-01-01

    Researchers in P.R.China commonly create triangulate irregular networks (TINs) from contours and then convert TINs into digital elevation models (DEMs). However, the DEM produced by this method can not precisely describe and simulate key hydrological features such as rivers and drainage borders. Taking a hilly region in southwestern China as a research area and using ArcGISTM software, we analyzed the errors of different interpolations to obtain distributions of the errors and precisions of different algorithms and to provide references for DEM productions. The results show that different interpolation errors satisfy normal distributions, and large error exists near the structure line of the terrain. Furthermore, the results also show that the precision of a DEM interpolated with the Australian National University digital elevation model (ANUDEM) is higher than that interpolated with TIN. The DEM interpolated with TIN is acceptable for generating DEMs in the hilly region of southwestern China.

  6. A muscle model for hybrid muscle activation

    Directory of Open Access Journals (Sweden)

    Klauer Christian

    2015-09-01

    Full Text Available To develop model-based control strategies for Functional Electrical Stimulation (FES in order to support weak voluntary muscle contractions, a hybrid model for describing joint motions induced by concurrent voluntary-and FES induced muscle activation is proposed. It is based on a Hammerstein model – as commonly used in feedback controlled FES – and exemplarily applied to describe the shoulder abduction joint angle. Main component of a Hammerstein muscle model is usually a static input nonlinearity depending on the stimulation intensity. To additionally incorporate voluntary contributions, we extended the static non-linearity by a second input describing the intensity of the voluntary contribution that is estimated by electromyography (EMG measurements – even during active FES. An Artificial Neural Network (ANN is used to describe the static input non-linearity. The output of the ANN drives a second-order linear dynamical system that describes the combined muscle activation and joint angle dynamics. The tunable parameters are adapted to the individual subject by a system identification approach using previously recorded I/O-data. The model has been validated in two healthy subjects yielding RMS values for the joint angle error of 3.56° and 3.44°, respectively.

  7. Locating Pleistocene Refugia: Comparing Phylogeographic and Ecological Niche Model Predictions

    Science.gov (United States)

    2007-07-01

    research groups [21,42–46], support the idea that the bioclimatic variables used in our ENM predictions (see Materials and Methods) are of importance to the...calibrating the downscaled LGM climate data to actual observed climate conditions. ENMs were based on the 19 bioclimatic variables in the WorldClim...phylogenetics and bioclimatic modeling. Systematic Biology 55: 785–802. 34. Graham CH, Ron SR, Santos JC, Schneider CJ, Moritz C (2004) Integrating

  8. COMPARATIVE STUDY ON ACCOUNTING MODELS "CASH" AND "ACCRUAL"

    OpenAIRE

    Tatiana Danescu; Luminita Rus

    2013-01-01

    Accounting, as a source of information, can recognize the economic transactionstaking into account the time of payment or receipt thereof, as soon as they occur. There are twobasic models of accounting: accrual basis and cash basis. In the cash accounting method thetransactions are recorded only when cash is received or paid, shall not make the difference betweenthe purchase of an asset and the payment of expenditure - both of which are considered"payments". Accrual accounting achieves this d...

  9. Concepts of disability: the Activity Space Model.

    Science.gov (United States)

    Kopec, J A

    1995-03-01

    This paper describes a new conceptual framework for functional assessment, the Activity Space Model (ASM). According to this model, functional impairments may lead to restrictions in an individual's activity space, a multidimensional space that represents human potential for activity. For each elementary ability, restrictions in the corresponding dimension of the activity space can be evaluated by deriving a difficulty curve that depicts the relationship between the level of performance and the psychophysical cost of activity. The effect of disease on daily functioning is explained in terms of a tradeoff between the psychophysical cost and the value of each act of behavior to the disabled individual. These two constructs are measured on the same scale and expressed in units of difficulty. The location of each task within the activity space in relation to the difficulty curve determines whether it will be performed or avoided at a given point in time. The ASM has both theoretical and practical implications. It offers a new, integrated perspective on disability and suggests new strategies for developing and evaluating functional assessment measures.

  10. An activation-recruitment scheme for use in muscle modeling.

    Science.gov (United States)

    Hawkins, D A; Hull, M L

    1992-12-01

    The derivation of a new activation-recruitment scheme and the results of a study designed to test its validity are presented. The activation scheme utilizes input data of processed surface EMG signals, muscle composition, muscle architecture, and experimentally determined activation coefficients. In the derivation, the relationship between muscle activation and muscle fiber recruitment was considered. In the experimental study, triceps muscle force was determined for isometric elbow extension tasks varying in intensity from 10 to 100% of a maximum voluntary contraction (MVC) using both a muscle model that incorporates the activation scheme, and inverse dynamics techniques. The forces calculated using the two methods were compared statistically. The modeled triceps force was not significantly different from the experimental results determined using inverse dynamics techniques for average activation levels greater than 25% of MVC, but was significantly different for activation levels less than 25% of MVC. These results lend support for use of the activation-recruitment scheme for moderate to large activation levels, and suggest that factors in addition to fiber recruitment play a role in force regulation at lower activation levels.

  11. Mathematical model of radon activity measurements

    Energy Technology Data Exchange (ETDEWEB)

    Paschuk, Sergei A.; Correa, Janine N.; Kappke, Jaqueline; Zambianchi, Pedro, E-mail: sergei@utfpr.edu.br, E-mail: janine_nicolosi@hotmail.com [Universidade Tecnologica Federal do Parana (UTFPR), Curitiba, PR (Brazil); Denyak, Valeriy, E-mail: denyak@gmail.com [Instituto de Pesquisa Pele Pequeno Principe, Curitiba, PR (Brazil)

    2015-07-01

    Present work describes a mathematical model that quantifies the time dependent amount of {sup 222}Rn and {sup 220}Rn altogether and their activities within an ionization chamber as, for example, AlphaGUARD, which is used to measure activity concentration of Rn in soil gas. The differential equations take into account tree main processes, namely: the injection of Rn into the cavity of detector by the air pump including the effect of the traveling time Rn takes to reach the chamber; Rn release by the air exiting the chamber; and radioactive decay of Rn within the chamber. Developed code quantifies the activity of {sup 222}Rn and {sup 220}Rn isotopes separately. Following the standard methodology to measure Rn activity in soil gas, the air pump usually is turned off over a period of time in order to avoid the influx of Rn into the chamber. Since {sup 220}Rn has a short half-life time, approximately 56s, the model shows that after 7 minutes the activity concentration of this isotope is null. Consequently, the measured activity refers to {sup 222}Rn, only. Furthermore, the model also addresses the activity of {sup 220}Rn and {sup 222}Rn progeny, which being metals represent potential risk of ionization chamber contamination that could increase the background of further measurements. Some preliminary comparison of experimental data and theoretical calculations is presented. Obtained transient and steady-state solutions could be used for planning of Rn in soil gas measurements as well as for accuracy assessment of obtained results together with efficiency evaluation of chosen measurements procedure. (author)

  12. Computational Models for Analysis of Illicit Activities

    DEFF Research Database (Denmark)

    Nizamani, Sarwat

    Numerous illicit activities happen in our society, which, from time to time affect the population by harming individuals directly or indirectly. Researchers from different disciplines have contributed to developing strategies to analyze such activities, in order to help law enforcement agents...... traditional models for both of the tasks. Apart from these globally organized crimes and cybercrimes, there happen specific world issues which affect geographic locations and take the form of bursts of public violence. These kinds of issues have received little attention by the academicians. These issues have...... to describe the phenomenon of contagious public outrage, which eventually leads to the spread of violence following a disclosure of some unpopular political decisions and/or activity. The results shed a new light on terror activity and provide some hint on how to curb the spreading of violence within...

  13. Comparing models for vesicant responses in skin cells

    Energy Technology Data Exchange (ETDEWEB)

    Mershon, M.M.; Rhoads, L.S.; Petrali, J.P.; Mills, K.R.; Kim, S.K.

    1993-05-13

    Vesicant challenges have been delivered to NHEK (normal human epidermal keratinocyes) and to artificial human epidermal tissues. Confluent NHEK, grown on plastic surfaces or gel-coated microporous membranes of Millicell CMR inserts, were challenged with vesicants diluted in cell culture medium. Testskin was provided on agarose nutrient gel as a cornified wafer of sufficient diameter to receive vesicant vapor from cups normally used to challenge animal skin. Stratum corneum of preproduction EpiDerm (PreEpiD) specimens were challenged with vesicant vapor from cups suspended inside of Millicells. Inverted phase contrast microscopy of NHEK on plastic revealed dose-related vesicant effects that could facilitate screening of antivesicants. Scanning electron microscopy (SEM) revealed vesicant effects in two distinctly different populations of NHEK on gel-coated inserts. SEM and transmission electron microscopy (TEM) of Testskin and PreEpiD disclosed structural differences between these models that became amplified in vesicant-challenged specimens. PreEpiD shows more promise than Testskin for screening of antivesicant topical skin protectants. However, both epidermal models lack the basal lamina that is needed for advanced antivesicant testing.

  14. Microbial comparative pan-genomics using binomial mixture models

    Directory of Open Access Journals (Sweden)

    Ussery David W

    2009-08-01

    Full Text Available Abstract Background The size of the core- and pan-genome of bacterial species is a topic of increasing interest due to the growing number of sequenced prokaryote genomes, many from the same species. Attempts to estimate these quantities have been made, using regression methods or mixture models. We extend the latter approach by using statistical ideas developed for capture-recapture problems in ecology and epidemiology. Results We estimate core- and pan-genome sizes for 16 different bacterial species. The results reveal a complex dependency structure for most species, manifested as heterogeneous detection probabilities. Estimated pan-genome sizes range from small (around 2600 gene families in Buchnera aphidicola to large (around 43000 gene families in Escherichia coli. Results for Echerichia coli show that as more data become available, a larger diversity is estimated, indicating an extensive pool of rarely occurring genes in the population. Conclusion Analyzing pan-genomics data with binomial mixture models is a way to handle dependencies between genomes, which we find is always present. A bottleneck in the estimation procedure is the annotation of rarely occurring genes.

  15. Comparative analysis of calculation models of railway subgrade

    Directory of Open Access Journals (Sweden)

    I.O. Sviatko

    2013-08-01

    Full Text Available Purpose. In transport engineering structures design, the primary task is to determine the parameters of foundation soil and nuances of its work under loads. It is very important to determine the parameters of shear resistance and the parameters, determining the development of deep deformations in foundation soils, while calculating the soil subgrade - upper track structure interaction. Search for generalized numerical modeling methods of embankment foundation soil work that include not only the analysis of the foundation stress state but also of its deformed one. Methodology. The analysis of existing modern and classical methods of numerical simulation of soil samples under static load was made. Findings. According to traditional methods of analysis of ground masses work, limitation and the qualitative estimation of subgrade deformations is possible only indirectly, through the estimation of stress and comparison of received values with the boundary ones. Originality. A new computational model was proposed in which it will be applied not only classical approach analysis of the soil subgrade stress state, but deformed state will be also taken into account. Practical value. The analysis showed that for accurate analysis of ground masses work it is necessary to develop a generalized methodology for analyzing of the rolling stock - railway subgrade interaction, which will use not only the classical approach of analyzing the soil subgrade stress state, but also take into account its deformed one.

  16. Lattice Boltzmann modeling of directional wetting: Comparing simulations to experiments

    Science.gov (United States)

    Jansen, H. Patrick; Sotthewes, Kai; van Swigchem, Jeroen; Zandvliet, Harold J. W.; Kooij, E. Stefan

    2013-07-01

    Lattice Boltzmann Modeling (LBM) simulations were performed on the dynamic behavior of liquid droplets on chemically striped patterned surfaces, ultimately with the aim to develop a predictive tool enabling reliable design of future experiments. The simulations accurately mimic experimental results, which have shown that water droplets on such surfaces adopt an elongated shape due to anisotropic preferential spreading. Details of the contact line motion such as advancing of the contact line in the direction perpendicular to the stripes exhibit pronounced similarities in experiments and simulations. The opposite of spreading, i.e., evaporation of water droplets, leads to a characteristic receding motion first in the direction parallel to the stripes, while the contact line remains pinned perpendicular to the stripes. Only when the aspect ratio is close to unity, the contact line also starts to recede in the perpendicular direction. Very similar behavior was observed in the LBM simulations. Finally, droplet movement can be induced by a gradient in surface wettability. LBM simulations show good semiquantitative agreement with experimental results of decanol droplets on a well-defined striped gradient, which move from high- to low-contact angle surfaces. Similarities and differences for all systems are described and discussed in terms of the predictive capabilities of LBM simulations to model direction wetting.

  17. Application of Mathematical Modeling Activities in Costarican High School Education

    Directory of Open Access Journals (Sweden)

    Karen Porras-Lizano

    2015-01-01

    Full Text Available This paper describes the experience gained in implementing mathematical modeling activities as a methodological strategy in teaching issues such as proportions, with a group of eighth year of an academic-day-school, located in the province of San Jose, Costa Rica in 2012. Different techniques for gathering information were applied, such as participant observation and questionnaires. Among the relevant results are the cyclical development of mathematical thinking of students in the stages of mathematical modeling (description, manipulation, prediction and validation for solving the problem; developing of teamwork skills; and appreciation of mathematics as a useful and effective discipline. To resolve the activities proposed in this study, social interactions such as sharing information, thoughts and ideas, were generated, stimulating the zone of proximal development of the participating students. Likewise, the mathematical modeling activities allowed students to have a positive role in mathematics classes, stimulating, in turn, a different attitude compared to regular classes.

  18. Double Modelling of the Dynamic of Activities in Rural Municipalities

    CERN Document Server

    Ternes, S; Huet, S; Deffuant, G

    2009-01-01

    Land use choices and activity prevalence in a selected territory are determined by individual preferences constrained by the characteristic of the analysed zone: population density, soil properties, urbanization level and other similar factors can drive individuals to make different kind of decisions about their occupations. Different approaches can be used to describe land use change, occupation prevalence and their reciprocal inter-relation. In this paper we describe two different kinds of approaches: an agent based model, centred on individual choices and an aggregated model describing the evolution of activity prevalence in terms of coupled differential equation. We use and we compare the two models to analyse the effect of territorial constraints, like the lack of employment in determined sectors, on the possible activity prevalence scenarios.

  19. Comparing demographic, health status and psychosocial strategies of audience segmentation to promote physical activity

    National Research Council Canada - National Science Library

    Boslaugh, Sarah E; Kreuter, Matthew W; Nicholson, Robert A; Naleid, Kimberly

    2005-01-01

    .... This study compares the results of audience segmentation for physical activity that is based on either demographic, health status or psychosocial variables alone, or a combination of all three types of variables...

  20. PROJECT ACTIVITY ANALYSIS WITHOUT THE NETWORK MODEL

    Directory of Open Access Journals (Sweden)

    S. Munapo

    2012-01-01

    Full Text Available

    ENGLISH ABSTRACT: This paper presents a new procedure for analysing and managing activity sequences in projects. The new procedure determines critical activities, critical path, start times, free floats, crash limits, and other useful information without the use of the network model. Even though network models have been successfully used in project management so far, there are weaknesses associated with the use. A network is not easy to generate, and dummies that are usually associated with it make the network diagram complex – and dummy activities have no meaning in the original project management problem. The network model for projects can be avoided while still obtaining all the useful information that is required for project management. What are required are the activities, their accurate durations, and their predecessors.

    AFRIKAANSE OPSOMMING: Die navorsing beskryf ’n nuwerwetse metode vir die ontleding en bestuur van die sekwensiële aktiwiteite van projekte. Die voorgestelde metode bepaal kritiese aktiwiteite, die kritieke pad, aanvangstye, speling, verhasing, en ander groothede sonder die gebruik van ’n netwerkmodel. Die metode funksioneer bevredigend in die praktyk, en omseil die administratiewe rompslomp van die tradisionele netwerkmodelle.

  1. Comparative modelling of chemical ordering in palladium-iridium nanoalloys

    Energy Technology Data Exchange (ETDEWEB)

    Davis, Jack B. A.; Johnston, Roy L., E-mail: r.l.johnston@bham.ac.uk [School of Chemistry, University of Birmingham, Birmingham B15 2TT (United Kingdom); Rubinovich, Leonid; Polak, Micha, E-mail: mpolak@bgu.ac.il [Department of Chemistry, Ben-Gurion University of the Negev, Beer-Sheva 84105 (Israel)

    2014-12-14

    Chemical ordering in “magic-number” palladium-iridium nanoalloys has been studied by means of density functional theory (DFT) computations, and compared to those obtained by the Free Energy Concentration Expansion Method (FCEM) using derived coordination dependent bond energy variations (CBEV), and by the Birmingham Cluster Genetic Algorithm using the Gupta potential. Several compositions have been studied for 38- and 79-atom particles as well as the site preference for a single Ir dopant atom in the 201-atom truncated octahedron (TO). The 79- and 38-atom nanoalloy homotops predicted for the TO by the FCEM/CBEV are shown to be, respectively, the global minima and competitive low energy minima. Significant reordering of minima predicted by the Gupta potential is seen after reoptimisation at the DFT level.

  2. Microbial comparative pan-genomics using binomial mixture models

    DEFF Research Database (Denmark)

    Ussery, David; Snipen, L; Almøy, T

    2009-01-01

    The size of the core- and pan-genome of bacterial species is a topic of increasing interest due to the growing number of sequenced prokaryote genomes, many from the same species. Attempts to estimate these quantities have been made, using regression methods or mixture models. We extend the latter...... approach by using statistical ideas developed for capture-recapture problems in ecology and epidemiology. RESULTS: We estimate core- and pan-genome sizes for 16 different bacterial species. The results reveal a complex dependency structure for most species, manifested as heterogeneous detection...... probabilities. Estimated pan-genome sizes range from small (around 2600 gene families) in Buchnera aphidicola to large (around 43000 gene families) in Escherichia coli. Results for Echerichia coli show that as more data become available, a larger diversity is estimated, indicating an extensive pool of rarely...

  3. Comparing and modelling land use organization in cities

    Science.gov (United States)

    Lenormand, Maxime; Picornell, Miguel; Cantú-Ros, Oliva G.; Louail, Thomas; Herranz, Ricardo; Barthelemy, Marc; Frías-Martínez, Enrique; San Miguel, Maxi; Ramasco, José J.

    2015-01-01

    The advent of geolocated information and communication technologies opens the possibility of exploring how people use space in cities, bringing an important new tool for urban scientists and planners, especially for regions where data are scarce or not available. Here we apply a functional network approach to determine land use patterns from mobile phone records. The versatility of the method allows us to run a systematic comparison between Spanish cities of various sizes. The method detects four major land use types that correspond to different temporal patterns. The proportion of these types, their spatial organization and scaling show a strong similarity between all cities that breaks down at a very local scale, where land use mixing is specific to each urban area. Finally, we introduce a model inspired by Schelling's segregation, able to explain and reproduce these results with simple interaction rules between different land uses. PMID:27019730

  4. Comparing and modeling land use organization in cities

    CERN Document Server

    Lenormand, Maxime; Cantú-Ros, Oliva G; Louail, Thomas; Herranz, Ricardo; Barthelemy, Marc; Frías-Martínez, Enrique; Miguel, Maxi San; Ramasco, José J

    2015-01-01

    The advent of geolocated ICT technologies opens the possibility of exploring how people use space in cities, bringing an important new tool for urban scientists and planners, especially for regions where data is scarce or not available. Here we apply a functional network approach to determine land use patterns from mobile phone records. The versatility of the method allows us to run a systematic comparison between Spanish cities of various sizes. The method detects four major land use types that correspond to different temporal patterns. The proportion of these types, their spatial organization and scaling show a strong similarity between all cities that breaks down at a very local scale, where land use mixing is specific to each urban area. Finally, we introduce a model inspired by Schelling's segregation, able to explain and reproduce these results with simple interaction rules between different land uses.

  5. Comparative digital cartilage histology for human and common osteoarthritis models

    Directory of Open Access Journals (Sweden)

    Pedersen DR

    2013-02-01

    Full Text Available Douglas R Pedersen, Jessica E Goetz, Gail L Kurriger, James A MartinDepartment of Orthopaedics and Rehabilitation, University of Iowa, Iowa City, IA, USAPurpose: This study addresses the species-specific and site-specific details of weight-bearing articular cartilage zone depths and chondrocyte distributions among humans and common osteoarthritis (OA animal models using contemporary digital imaging tools. Histological analysis is the gold-standard research tool for evaluating cartilage health, OA severity, and treatment efficacy. Historically, evaluations were made by expert analysts. However, state-of-the-art tools have been developed that allow for digitization of entire histological sections for computer-aided analysis. Large volumes of common digital cartilage metrics directly complement elucidation of trends in OA inducement and concomitant potential treatments.Materials and methods: Sixteen fresh human knees, 26 adult New Zealand rabbit stifles, and 104 bovine lateral plateaus were measured for four cartilage zones and the cell densities within each zone. Each knee was divided into four weight-bearing sites: the medial and lateral plateaus and femoral condyles.Results: One-way analysis of variance followed by pairwise multiple comparisons (Holm–Sidak method at a significance of 0.05 clearly confirmed the variability between cartilage depths at each site, between sites in the same species, and between weight-bearing articular cartilage definitions in different species.Conclusion: The present study clearly demonstrates multisite, multispecies differences in normal weight-bearing articular cartilage, which can be objectively quantified by a common digital histology imaging technique. The clear site-specific differences in normal cartilage must be taken into consideration when characterizing the pathoetiology of OA models. Together, these provide a path to consistently analyze the volume and variety of histologic slides necessarily generated

  6. Use of models in large-area forest surveys: comparing model-assisted, model-based and hybrid estimation

    Directory of Open Access Journals (Sweden)

    Göran Ståhl

    2016-02-01

    Full Text Available This paper focuses on the use of models for increasing the precision of estimators in large-area forest surveys. It is motivated by the increasing availability of remotely sensed data, which facilitates the development of models predicting the variables of interest in forest surveys. We present, review and compare three different estimation frameworks where models play a core role: model-assisted, model-based, and hybrid estimation. The first two are well known, whereas the third has only recently been introduced in forest surveys. Hybrid inference mixes designbased and model-based inference, since it relies on a probability sample of auxiliary data and a model predicting the target variable from the auxiliary data..We review studies on large-area forest surveys based on model-assisted, modelbased, and hybrid estimation, and discuss advantages and disadvantages of the approaches. We conclude that no general recommendations can be made about whether model-assisted, model-based, or hybrid estimation should be preferred. The choice depends on the objective of the survey and the possibilities to acquire appropriate field and remotely sensed data. We also conclude that modelling approaches can only be successfully applied for estimating target variables such as growing stock volume or biomass, which are adequately related to commonly available remotely sensed data, and thus purely field based surveys remain important for several important forest parameters. Keywords: Design-based inference, Model-assisted estimation, Model-based inference, Hybrid inference, National forest inventory, Remote sensing, Sampling

  7. A comparative QSAR study on the estrogenic activities of persistent organic pollutants by PLS and SVM

    Directory of Open Access Journals (Sweden)

    Fei Li

    2015-11-01

    Full Text Available Quantitative structure-activity relationships (QSARs were determined using partial least square (PLS and support vector machine (SVM. The predicted values by the final QSAR models were in good agreement with the corresponding experimental values. Chemical estrogenic activities are related to atomic properties (atomic Sanderson electronegativities, van der Waals volumes and polarizabilities. Comparison of the results obtained from two models, the SVM method exhibited better overall performances. Besides, three PLS models were constructed for some specific families based on their chemical structures. These predictive models should be useful to rapidly identify potential estrogenic endocrine disrupting chemicals.

  8. A Comparative Evaluation of Mixed Dentition Analysis on Reliability of Cone Beam Computed Tomography Image Compared to Plaster Model.

    Science.gov (United States)

    Gowd, Snigdha; Shankar, T; Dash, Samarendra; Sahoo, Nivedita; Chatterjee, Suravi; Mohanty, Pritam

    2017-01-01

    The aim of the study was to evaluate the reliability of cone beam computed tomography (CBCT) obtained image over plaster model for the assessment of mixed dentition analysis. Thirty CBCT-derived images and thirty plaster models were derived from the dental archives, and Moyer's and Tanaka-Johnston analyses were performed. The data obtained were interpreted and analyzed statistically using SPSS 10.0/PC (SPSS Inc., Chicago, IL, USA). Descriptive and analytical analysis along with Student's t-test was performed to qualitatively evaluate the data and P plaster model; the mean for Moyer's analysis in the left and right lower arch for CBCT and plaster model was 21.2 mm, 21.1 mm and 22.5 mm, 22.5 mm, respectively. CBCT-derived images were less reliable as compared to data obtained directly from plaster model for mixed dentition analysis.

  9. Comparative study of hypoglycemic and antibacterial activity of organic extracts of four Bangladeshi plants

    Directory of Open Access Journals (Sweden)

    Mohammad Shah Hafez Kabir

    2016-03-01

    Full Text Available Objective: To examine hypoglycemic and antibacterial activity against some Gram-positive and Gram-negative bacteria of organic extracts of four Bangladeshi plants. Methods: An in vivo hypoglycemic effect on mice model was used to check the hypoglycemic effect of four Bangladeshi herbal organic extracts viz., roots of Curculigo recurvata W. T. Aiton (Satipata (C. recurvata, leaf of Amorphophallus bulbifer Roxb. (Olkachu (A. bulbifer, whole plant of Thunbergia grandiflora Roxb. (Nillata (T. grandiflora and leaf of Steudnera colocasiifolia K. Koch (Yunnan (S. colocasiifolia using glibenclamide as a positive control and water as a negative control. They were also tested for antibacterial activity on three Grampositive and four Gram-negative bacteria by disk diffusion method. C. recurvata, A. bulbifer and T. grandiflora were extracted with methanol and S. colocasiifolia was extracted with ethanol. Results: Among all the plant extract, only ethanol extract of S. colocasiifolia leaves at 800 mg/ kg dose significantly (P < 0.01 reduced fasting glucose level in normal mice as compared to standard drug glibenclamide (5 mg/kg. Ethanol extract of S. colocasiifolia leaves at 800 mg/ kg dose decreased 20.28% of blood glucose level after 2 h of administration in normal mice, where glibenclamide decreased 39.63%. Methanol extract of T. grandiflra didn’t show any zone of inhibition against the tested bacteria, but other three extracts showed a wide range of zone of inhibition. However, none of the extract showed antibacterial activity against all the tested bacteria. Methanol extract of C. recurvata showed maximum zone of inhibition against Bacillus cereus [(10.50 ± 0.50 mm], Salmonella typhi [(16.20 ± 1.26 mm], Escherichia coli [(13.00 ± 1.00 mm] and ethanol extract of S. colocasiifolia showed maximum zone of inhibition against Staphylococcus aureus [(11.20 ± 1.26 (mm], Bacillus subtilis [(12.00 ± 0.50 (mm], Salmonella paratyphi [(10.80 ± 0.29 (mm

  10. Wind Tunnel Experiments with Active Control of Bridge Section Model

    DEFF Research Database (Denmark)

    Hansen, Henriette I.; Thoft-Christensen, Palle

    the flutter wind velocity for future ultra-long span suspension bridges. The purpose of the wind tunnel experiments is to investigate the principle to use this active flap control system. The bridge section model used in the experiments is therefore not a model of a specific bridge but it is realistic......This paper describes results of wind tunnel experiments with a bridge section model where movable flaps are integrated in the bridge girder so each flap is the streamlined part of the edge of the girder. This active control flap system is patented by COWIconsult and may be used to increase...... compared with a real bridge. Five flap configurations are investigated during the wind tunnel experiments and depending on the actual flap configuration it is possible to decrease or increase the flutter wind velocity for the model....

  11. Task decomposition: a framework for comparing diverse training models in human brain plasticity studies

    Directory of Open Access Journals (Sweden)

    Emily B. J. Coffey

    2013-10-01

    Full Text Available Training studies, in which the structural or functional neurophysiology is compared before and after expertise is acquired, are increasingly being used as models for understanding the human brain’s potential for reorganization. It is proving difficult to use these results to answer basic and important questions like how task training leads to both specific and general changes in behaviour and how these changes correspond with modifications in the brain. The main culprit is the diversity of paradigms used as complex task models. An assortment of activities ranging from juggling to deciphering Morse code has been reported. Even when working in the same general domain, few researchers use similar training models. New ways to meaningfully compare complex tasks are needed. We propose a method for characterizing and deconstructing the task requirements of complex training paradigms, which is suitable for application to both structural and functional neuroimaging studies. We believe this approach will aid brain plasticity research by making it easier to compare training paradigms, identify ‘missing puzzle pieces’, and encourage researchers to design training protocols to bridge these gaps.

  12. A Comparative Analysis of Community Wind Power DevelopmentModels

    Energy Technology Data Exchange (ETDEWEB)

    Bolinger, Mark; Wiser, Ryan; Wind, Tom; Juhl, Dan; Grace, Robert; West, Peter

    2005-05-20

    For years, farmers in the United States have looked with envy on their European counterparts ability to profitably farm the wind through ownership of distributed, utility-scale wind projects. Only within the past few years, however, has farmer- or community-owned windpower development become a reality in the United States. The primary hurdle to this type of development in the United States has been devising and implementing suitable business and legal structures that enable such projects to take advantage of tax-based federal incentives for windpower. This article discusses the limitations of such incentives in supporting farmer- or community-owned wind projects, describes four ownership structures that potentially overcome such limitations, and finally conducts comparative financial analysis on those four structures, using as an example a hypothetical 1.5 MW farmer-owned project located in the state of Oregon. We find that material differences in the competitiveness of each structure do exist, but that choosing the best structure for a given project will largely depend on the conditions at hand; e.g., the ability of the farmer(s) to utilize tax credits, preference for individual versus cooperative ownership, and the state and utility service territory in which the project will be located.

  13. Spheroid model study comparing the biocompatibility of Biodentine and MTA.

    Science.gov (United States)

    Pérard, Matthieu; Le Clerc, Justine; Watrin, Tanguy; Meary, Fleur; Pérez, Fabienne; Tricot-Doleux, Sylvie; Pellen-Mussi, Pascal

    2013-06-01

    The primary objective of this study was to assess the biological effects of a new dentine substitute based on Ca₃SiO₅ (Biodentine™) for use in pulp-capping treatment, on pseudo-odontoblastic (MDPC-23) and pulp (Od-21) cells. The secondary objective was to evaluate the effects of Biodentine and mineral trioxide aggregate (MTA) on gene expression in cultured spheroids. We used the acid phosphatase assay to compare the biocompatibility of Biodentine and MTA. Cell differentiation was investigated by RT-qPCR. We investigated the expression of genes involved in odontogenic differentiation (Runx2), matrix secretion (Col1a1, Spp1) and mineralisation (Alp). ANOVA and PLSD tests were used for data analysis. MDPC-23 cells cultured in the presence of MTA had higher levels of viability than those cultured in the presence of Biodentine and control cells on day 7 (P = 0.0065 and P = 0.0126, respectively). For Od-21 cells, proliferation rates on day 7 were significantly lower in the presence of Biodentine or MTA than for control (P MTA than in those cultured in the presence of Biodentine and in control cells. Biodentine and MTA may modify the proliferation of pulp cell lines. Their effects may fluctuate over time, depending on the cell line considered. The observed similarity between Biodentine and MTA validates the indication for direct pulp-capping claimed by the manufacturers.

  14. Comparing Two Forms of Concept Map Critique Activities to Facilitate Knowledge Integration Processes in Evolution Education

    Science.gov (United States)

    Schwendimann, Beat A.; Linn, Marcia C.

    2016-01-01

    Concept map activities often lack a subsequent revision step that facilitates knowledge integration. This study compares two collaborative critique activities using a Knowledge Integration Map (KIM), a form of concept map. Four classes of high school biology students (n?=?81) using an online inquiry-based learning unit on evolution were assigned…

  15. Comparing Primary Student Teachers' Attitudes, Subject Knowledge and Pedagogical Content Knowledge Needs in a Physics Activity

    Science.gov (United States)

    Johnston, Jane; Ahtee, Maija

    2006-01-01

    This research explores and compares primary student teachers' attitudes, subject knowledge and pedagogical content knowledge (PCK) in physics in two institutions in England and Finland, using a practical physics activity and questionnaire. Teaching of physics activities was rated unpopular both in Finland and England, although English students…

  16. Comparing Activity Patterns, Biological, and Family Factors in Children with and without Developmental Coordination Disorder

    Science.gov (United States)

    Beutum, Monique Natalie; Cordier, Reinie; Bundy, Anita

    2013-01-01

    The association between motor proficiency and moderate to vigorous physical activity (MVPA) suggests children with developmental coordination disorder (DCD) may be susceptible to inactivity-related conditions such as cardiovascular diseases. The aim of this study was to compare children with and without DCD on physical activity patterns, activity…

  17. Charcoal and activated carbon as adsorbate of phytotoxic compounds - a comparative study.

    NARCIS (Netherlands)

    Hille, M.G.; Ouden, den J.

    2005-01-01

    This study compares the potential of natural charcoal from Scots pine (Pinus sylvestris L.) and activated carbon to improve germination under the hypothesis that natural charcoal adsorbs phytotoxins produced by dwarf-shrubs, but due to it's chemical properties to a lesser extent than activated carbo

  18. Comparing Primary Student Teachers' Attitudes, Subject Knowledge and Pedagogical Content Knowledge Needs in a Physics Activity

    Science.gov (United States)

    Johnston, Jane; Ahtee, Maija

    2006-01-01

    This research explores and compares primary student teachers' attitudes, subject knowledge and pedagogical content knowledge (PCK) in physics in two institutions in England and Finland, using a practical physics activity and questionnaire. Teaching of physics activities was rated unpopular both in Finland and England, although English students…

  19. Comparing Role-Playing Activities in Second Life and Face-to-Face Environments

    Science.gov (United States)

    Gao, Fei; Noh, Jeongmin J.; Koehler, Matthew J.

    2009-01-01

    This study compared student performances in role-playing activities in both a face-to-face (FTF) environment and a virtual 3D environment, Second Life (SL). We found that students produced a similar amount of communication in the two environments, but the communication styles were different. In SL role-playing activities, students took more…

  20. Object tracking using active appearance models

    DEFF Research Database (Denmark)

    Stegmann, Mikkel Bille

    2001-01-01

    This paper demonstrates that (near) real-time object tracking can be accomplished by the deformable template model; the Active Appearance Model (AAM) using only low-cost consumer electronics such as a PC and a web-camera. Successful object tracking of perspective, rotational and translational...... transformations was carried out using a training set of five images. The tracker was automatically initialised by a described multi-scale initialisation method and achieved a performance in the range of 7-10 frames per second....

  1. COMPARATIVE SUDY OF THE ELECTROENCEPHALOGRAPHIC ACTIVITY AT PROFESSIONAL HANDBALL AND FENCERS PLAYERS

    OpenAIRE

    DENISA ENESCU BIERU; MIRELA LUCIA CĂLINA; ALICE GUSTI; VALENTINA DINU; GERMINA COSMA; MIHAI MARIAN DRAGOMIR; CĂTALIN FORłAN; CĂTĂLIN POPESCU

    2010-01-01

    Purpose. Our purpose was to study the electroencephalographic activity of professional handball and fencers players, to compare the obtained data and to identify a possible neurophysiologic pattern associate to practiced sportive activity. Material and method. The study was performed on a group of 22 male athletes, 11 handball players and 11 fencers (different stress degrees of the upper members), active for between 5 and 12 years exclusively in eitherhandball or fencing. Using Nihon-Kohden E...

  2. Modelling Proteasome and Proteasome Regulator Activities

    Directory of Open Access Journals (Sweden)

    Juliane Liepe

    2014-06-01

    Full Text Available Proteasomes are key proteases involved in a variety of processes ranging from the clearance of damaged proteins to the presentation of antigens to CD8+ T-lymphocytes. Which cleavage sites are used within the target proteins and how fast these proteins are degraded have a profound impact on immune system function and many cellular metabolic processes. The regulation of proteasome activity involves different mechanisms, such as the substitution of the catalytic subunits, the binding of regulatory complexes to proteasome gates and the proteasome conformational modifications triggered by the target protein itself. Mathematical models are invaluable in the analysis; and potentially allow us to predict the complex interactions of proteasome regulatory mechanisms and the final outcomes of the protein degradation rate and MHC class I epitope generation. The pioneering attempts that have been made to mathematically model proteasome activity, cleavage preference variation and their modification by one of the regulatory mechanisms are reviewed here.

  3. A comparative study of oxidant-antioxidant status in stable and active vitiligo patients.

    Science.gov (United States)

    Ines, Dammak; Sonia, Boudaya; Riadh, Ben Mansour; Amel, El Gaied; Slaheddine, Marrekchi; Hamida, Turki; Hamadi, Attia; Basma, Hentati

    2006-09-01

    The pathogenetic mechanisms in vitiligo have not been completely clarified. One of the major hypotheses in the pathogenesis of vitiligo is the oxidative stress hypothesis. The active or stable phase of vitiligo is defined on the basis of the progression or appearance of new lesions in the last 3 months and the absence of new lesions or their progression in the last 6 months, respectively. Eighteen patients with active vitiligo, 18 patients with stable vitiligo, and 40 controls were included in this study. We examined serum levels of malondialdehyde, selenium, vitamin E and A, and the erythrocyte activities of glutathione peroxidase, superoxide dismutase, and catalase. Our results revealed a significantly higher level of serum malondialdehyde, selenium in patients with active disease compared with the controls. Significant higher increase in erythrocytes superoxide dismutase activities was observed in active vitiligo group, erythrocyte glutathione peroxidase activity was decreased significantly in active disease, whereas erythrocyte catalase activity and plasma vitamin E and A levels were not different in vitiligo patients as compared with controls. Our study shows that oxidative stress is involved in the pathophysiology of both active and stable vitiligo but increased imbalance of antioxidants was observed in the blood of active vitiligo patients.

  4. Internal Model Based Active Disturbance Rejection Control

    OpenAIRE

    Pan, Jinwen; Wang, Yong

    2016-01-01

    The basic active disturbance rejection control (BADRC) algorithm with only one order higher extended state observer (ESO) proves to be robust to both internal and external disturbances. An advantage of BADRC is that in many applications it can achieve high disturbance attenuation level without requiring a detailed model of the plant or disturbance. However, this can be regarded as a disadvantage when the disturbance characteristic is known since the BADRC algorithm cannot exploit such informa...

  5. COMPARATIVE STUDY OF ANTI-INFLAMMATORY ACTIVITY OF NEWER MACROLIDES WITH ETORICOXIB

    Directory of Open Access Journals (Sweden)

    Gajendra Naidu

    2014-03-01

    Full Text Available The present study was designed to investigate the anti-inflammatory activity of macrolides and to compare with standard non- steroidal anti-inflammatory drug (NSAID etoricoxib. This study was conducted in male wistar albino rats by inducing edema with 1% carrageenan. Animals were divided into 5 groups with 6 in each and paw edema volume was measured by digital plethysmograph before and 3hrs after 1% carrageenan administration. Percentage of inhibition of paw edema was calculated. Results showed macrolides having significant anti-inflammatory activity & the anti-inflammatory activity of roxithromycin was almost equally comparable with etoricoxib

  6. Alkali activated fly ash binders. A comparative study between sodium and potassium activators

    Directory of Open Access Journals (Sweden)

    Criado, M.

    2006-03-01

    Full Text Available This paper shows the effect of the nature of some alkaline activators in the microstructural development of thermal-alkali activated f/y ash systems. The alkaline compounds employed in this investigation were: NaOH, KOH, Na2C03, K2C03, sodium silicate and potassium silicate. Results confirm that the main reaction product of the activation process (throughout the studied systems is the amorphous alkaline aluminosilicate gel with a three-dimensional structure already observed in earlier research. It has been proved that the type of anion and cation involved in the activation reaction of the ashes not only affects the microstructural development of the systems but the Si/Al ratio of that prezeolitic gel too. For example, in the presence of soluble silicate ions the content of Si in the final structure is notably increased (Si/Al =2.7-3.0, however carbonate ions play a different role since the formation of Sodium or Potassium carbonate/bicarbonate acidifies the system and consequently the reaction rate is considerably slowed. Finally it is evident that; when all experimental conditions are equal, sodium has a greater capacity than potassium to accelerate the setting and hardening reactions of fly ash and also to stimulate the growth of certain zeolitic crystals (reaction by-products. In general it can be affirmed that OH- ion acts as a reaction catalyst; and the alkaline metal (M+ acts as a structure-forming element.Este trabajo muestra el efecto de la naturaleza del activador alcalino en el desarrollo microestructural de sistemas de ceniza volante, activados térmica y alcalinamente. Los componentes alcalinos empleados en esta investigación fueron: NaOH, KOH, Na2C03, K2C03, silicato sódico y silicato potásico. Los resultados obtenidos confirman que el principal producto de reacción del proceso de activación (a través de los sistemas estudiados es un gel de aluminosilicato alcalino amorfo con estructura tridimensional ya observada en trabajos

  7. Relationship between disease activity and hearing impairment in patients with rheumatoid arthritis compared with controls.

    Science.gov (United States)

    Yildirim, Adem; Surucu, Gulseren; Dogan, Sedat; Karabiber, Mehmet

    2016-02-01

    The characteristics of hearing impairment (HI) in rheumatoid arthritis (RA) are still poorly understood, and their association with disease activity is based on conflicting information. This study compared HI between RA patients and controls and between active and remission RA groups using multi-frequency audiometry. This study enrolled 88 RA patients and 50 controls. The pure-tone hearing thresholds at 500 to 4000 Hz for air (AC) and bone (BC) conduction were compared between RA and controls as well as between active and remission RA patients using DAS28-CRP scores. The pure-tone hearing thresholds for AC and BC were significantly higher at high frequencies (2000 and 4000 Hz) in the RA group for both ears compared with controls. In addition, the BC threshold at 1000 Hz for the right ear was higher in the RA group than controls. When active and remission RA patients were compared, the thresholds were higher only at 4000 Hz for both ears for AC and BC in patients with active RA. The air-bone gap differed significantly at 2000 and 4000 Hz in both ears. This study demonstrated that patients with RA have a heightened risk of HI, and disease activity increases this risk, particularly at high frequencies. Clinicians who manage RA should be aware of HI and consider performing audiological evaluations in RA patients with active disease in particular.

  8. On a Quantum Model of Brain Activities

    Science.gov (United States)

    Fichtner, K.-H.; Fichtner, L.; Freudenberg, W.; Ohya, M.

    2010-01-01

    One of the main activities of the brain is the recognition of signals. A first attempt to explain the process of recognition in terms of quantum statistics was given in [6]. Subsequently, details of the mathematical model were presented in a (still incomplete) series of papers (cf. [7, 2, 5, 10]). In the present note we want to give a general view of the principal ideas of this approach. We will introduce the basic spaces and justify the choice of spaces and operations. Further, we bring the model face to face with basic postulates any statistical model of the recognition process should fulfill. These postulates are in accordance with the opinion widely accepted in psychology and neurology.

  9. Pore water pressure variations in Subpermafrost groundwater : Numerical modeling compared with experimental modeling

    Science.gov (United States)

    Rivière, Agnès.; Goncalves, Julio; Jost, Anne; Font, Marianne

    2010-05-01

    Development and degradation of permafrost directly affect numerous hydrogeological processes such as thermal regime, exchange between river and groundwater, groundwater flows patterns and groundwater recharge (Michel, 1994). Groundwater in permafrost area is subdivided into two zones: suprapermafrost and subpermafrost which are separated by permafrost. As a result of the volumetric expansion of water upon freezing and assuming ice lenses and frost heave do not form freezing in a saturated aquifer, the progressive formation of permafrost leads to the pressurization of the subpermafrost groundwater (Wang, 2006). Therefore disappearance or aggradation of permafrost modifies the confined or unconfined state of subpermafrost groundwater. Our study focuses on modifications of pore water pressure of subpermafrost groundwater which could appear during thawing and freezing of soil. Numerical simulation allows elucidation of some of these processes. Our numerical model accounts for phase changes for coupled heat transport and variably saturated flow involving cycles of freezing and thawing. The flow model is a combination of a one-dimensional channel flow model which uses Manning-Strickler equation and a two-dimensional vertically groundwater flow model using Richards equation. Numerical simulation of heat transport consisted in a two dimensional model accounting for the effects of latent heat of phase change of water associated with melting/freezing cycles which incorporated the advection-diffusion equation describing heat-transfer in porous media. The change of hydraulic conductivity and thermal conductivity are considered by our numerical model. The model was evaluated by comparing predictions with data from laboratory freezing experiments. Experimental design was undertaken at the Laboratory M2C (Univesité de Caen-Basse Normandie, CNRS, France). The device consisted of a Plexiglas box insulated on all sides except on the top. Precipitation and ambient temperature are

  10. Comparing physically-based and statistical landslide susceptibility model outputs - a case study from Lower Austria

    Science.gov (United States)

    Canli, Ekrem; Thiebes, Benni; Petschko, Helene; Glade, Thomas

    2015-04-01

    By now there is a broad consensus that due to human-induced global change the frequency and magnitude of heavy precipitation events is expected to increase in certain parts of the world. Given the fact, that rainfall serves as the most common triggering agent for landslide initiation, also an increased landside activity can be expected there. Landslide occurrence is a globally spread phenomenon that clearly needs to be handled. The present and well known problems in modelling landslide susceptibility and hazard give uncertain results in the prediction. This includes the lack of a universal applicable modelling solution for adequately assessing landslide susceptibility (which can be seen as the relative indication of the spatial probability of landslide initiation). Generally speaking, there are three major approaches for performing landslide susceptibility analysis: heuristic, statistical and deterministic models, all with different assumptions, its distinctive data requirements and differently interpretable outcomes. Still, detailed comparison of resulting landslide susceptibility maps are rare. In this presentation, the susceptibility modelling outputs of a deterministic model (Stability INdex MAPping - SINMAP) and a statistical modelling approach (generalized additive model - GAM) are compared. SINMAP is an infinite slope stability model which requires parameterization of soil mechanical parameters. Modelling with the generalized additive model, which represents a non-linear extension of a generalized linear model, requires a high quality landslide inventory that serves as the dependent variable in the statistical approach. Both methods rely on topographical data derived from the DTM. The comparison has been carried out in a study area located in the district of Waidhofen/Ybbs in Lower Austria. For the whole district (ca. 132 km²), 1063 landslides have been mapped and partially used within the analysis and the validation of the model outputs. The respective

  11. An Activation Threshold Model for Response Inhibition

    Science.gov (United States)

    MacDonald, Hayley J.; McMorland, Angus J. C.; Stinear, Cathy M.; Coxon, James P.; Byblow, Winston D.

    2017-01-01

    Reactive response inhibition (RI) is the cancellation of a prepared response when it is no longer appropriate. Selectivity of RI can be examined by cueing the cancellation of one component of a prepared multi-component response. This substantially delays execution of other components. There is debate regarding whether this response delay is due to a selective neural mechanism. Here we propose a computational activation threshold model (ATM) and test it against a classical “horse-race” model using behavioural and neurophysiological data from partial RI experiments. The models comprise both facilitatory and inhibitory processes that compete upstream of motor output regions. Summary statistics (means and standard deviations) of predicted muscular and neurophysiological data were fit in both models to equivalent experimental measures by minimizing a Pearson Chi-square statistic. The ATM best captured behavioural and neurophysiological dynamics of partial RI. The ATM demonstrated that the observed modulation of corticomotor excitability during partial RI can be explained by nonselective inhibition of the prepared response. The inhibition raised the activation threshold to a level that could not be reached by the original response. This was necessarily followed by an additional phase of facilitation representing a secondary activation process in order to reach the new inhibition threshold and initiate the executed component of the response. The ATM offers a mechanistic description of the neural events underlying RI, in which partial movement cancellation results from a nonselective inhibitory event followed by subsequent initiation of a new response. The ATM provides a framework for considering and exploring the neuroanatomical constraints that underlie RI. PMID:28085907

  12. Modelling of Activated Sludge Wastewater Treatment

    Directory of Open Access Journals (Sweden)

    Kurtanjeka, Ž.

    2008-02-01

    Full Text Available Activated sludge wastewater treatment is a highly complex physical, chemical and biological process, and variations in wastewater flow rate and its composition, combined with time-varying reactions in a mixed culture of microorganisms, make this process non-linear and unsteady. The efficiency of the process is established by measuring the quantities that indicate quality of the treated wastewater, but they can only be determined at the end of the process, which is when the water has already been processed and is at the outlet of the plant and released into the environment.If the water quality is not acceptable, it is already too late for its improvement, which indicates the need for a feed forward process control based on a mathematical model. Since there is no possibility of retracing the process steps back, all the mistakes in the control of the process could induce an ecological disaster of a smaller or bigger extent. Therefore, models that describe this process well may be used as a basis for monitoring and optimal control of the process development. This work analyzes the process of biological treatment of wastewater in the Velika Gorica plant. Two empirical models for the description of the process were established, multiple linear regression model (MLR with 16 predictor variables and piecewise linear regression model (PLR with 17 predictor variables. These models were developed with the aim to predict COD value of the effluent wastewater at the outlet, after treatment. The development of the models is based on the statistical analysis of experimental data, which are used to determine the relations among individual variables. In this work are applied linear models based on multiple linear regression (MLR and partial least squares (PLR methods. The used data were obtained by everyday measurements of the quantities that indicate the quality of the input and output water, working conditions of the plant and the quality of the activated sludge

  13. Comparative analysis of realistic CT-scan and simplified human airway models in airflow simulation.

    Science.gov (United States)

    Johari, Nasrul Hadi; Osman, Kahar; Helmi, Nor Harris N; Abdul Kadir, Mohammed A Rafiq

    2015-01-01

    Efforts to model the human upper respiratory system have undergone many phases. Geometrical proximity to the realistic shape has been the subject of many research projects. In this study, three different geometries of the trachea and main bronchus were modelled, which were reconstructed from computed tomography (CT) scan images. The geometrical variations were named realistic, simplified and oversimplified. Realistic refers to the lifelike image taken from digital imaging and communications in medicine format CT scan images, simplified refers to the reconstructed image based on natural images without realistic details pertaining to the rough surfaces, and oversimplified describes the straight wall geometry of the airway. The characteristics of steady state flows with different flow rates were investigated, simulating three varied physical activities and passing through each model. The results agree with previous studies where simplified models are sufficient for providing comparable results for airflow in human airways. This work further suggests that, under most exercise conditions, the idealised oversimplified model is not favourable for simulating either airflow regimes or airflow with particle depositions. However, in terms of immediate analysis for the prediction of abnormalities of various dimensions of human airways, the oversimplified techniques may be used.

  14. Comparing models of debris-flow susceptibility in the alpine environment

    Science.gov (United States)

    Carrara, Alberto; Crosta, Giovanni; Frattini, Paolo

    Debris-flows are widespread in Val di Fassa (Trento Province, Eastern Italian Alps) where they constitute one of the most dangerous gravity-induced surface processes. From a large set of environmental characteristics and a detailed inventory of debris flows, we developed five models to predict location of debris-flow source areas. The models differ in approach (statistical vs. physically-based) and type of terrain unit of reference (slope unit vs. grid cell). In the statistical models, a mix of several environmental factors classified areas with different debris-flow susceptibility; however, the factors that exert a strong discriminant power reduce to conditions of high slope-gradient, pasture or no vegetation cover, availability of detrital material, and active erosional processes. Since slope and land use are also used in the physically-based approach, all model results are largely controlled by the same leading variables. Overlaying susceptibility maps produced by the different methods (statistical vs. physically-based) for the same terrain unit of reference (grid cell) reveals a large difference, nearly 25% spatial mismatch. The spatial discrepancy exceeds 30% for susceptibility maps generated by the same method (discriminant analysis) but different terrain units (slope unit vs. grid cell). The size of the terrain unit also led to different susceptibility maps (almost 20% spatial mismatch). Maps based on different statistical tools (discriminant analysis vs. logistic regression) differed least (less than 10%). Hence, method and terrain unit proved to be equally important in mapping susceptibility. Model performance was evaluated from the percentages of terrain units that each model correctly classifies, the number of debris-flow falling within the area classified as unstable by each model, and through the metric of ROC curves. Although all techniques implemented yielded results essentially comparable; the discriminant model based on the partition of the study

  15. An immunological model for detecting bot activities

    Science.gov (United States)

    Karim, Md E.; Phoha, Vir V.; Sultan, Md A.

    2009-05-01

    We develop a hierarchical immunological model to detect bot activities in a computer network. In the proposed model antibody (detector)-antigen (foreign object) reactions are defined using negative selection based approach and negative systems-properties are defined by various temporal as well as non-temporal systems features. Theory of sequential hypothesis testing has been used in the literature for identifying spatial-temporal correlations among malicious remote hosts and among the bots within a botnet. We use it for combining multiple immunocomputing based decisions too. Negative selection based approach defines a self and helps identifying non-selves. We define non-selves with respect to various systems characteristics and then use different combinations of non-selves to design bot detectors. Each detector operates at the client sites of the network under surveillance. A match with any of the detectors suggests presence of a bot. Preliminary results suggest that the proposed model based solutions can improve the identification of bot activities.

  16. Carbon dioxide captured by multi-walled carbon nanotube and activated charcoal: A comparative study

    Directory of Open Access Journals (Sweden)

    Khalili Soodabeh

    2013-01-01

    Full Text Available this study, the equilibrium adsorption of CO2 on activated charcoal (AC and multi-walled carbon nanotube (MWCNT were investigated. Experiments were performed at temperature range of 298-318 K and pressures up to 40 bars. The obtained results indicated that the equilibrium uptakes of CO2 by both adsorbents increased with increasing pressure and decreasing temperature. In spite of lower specific surface area, the maximum amount of CO2 uptake achieved by MWCNT at 298K and 40 bars were twice of CO2 capture by AC (15 mmol.g-1 compared to 7.93 mmol.g-1. The higher CO2 captured by MWCNT can be attributed to its higher pore volume and specific structure of MWCN T such as hollowness and light mass which had greater influence than specific surface area. The experimental data were analyzed by means of Freundlich and Langmuir adsorption isotherm models. Following a simple acidic treatment procedure increased marginally CO2 capture by MWCNT over entire range of pressure, while for AC this effect appeared at higher pressures. Small values of isosteric heat of adsorption were evaluated based on Clausius-Clapeyron equation showed the physical nature of adsorption mechanism. The high amount of CO2 capture by MWCNT renders it as a promising carrier for practical applications such as gas separation.

  17. MultiMetEval : Comparative and Multi-Objective Analysis of Genome-Scale Metabolic Models

    NARCIS (Netherlands)

    Zakrzewski, Piotr; Medema, Marnix H.; Gevorgyan, Albert; Kierzek, Andrzej M.; Breitling, Rainer; Takano, Eriko; Fong, Stephen S.

    2012-01-01

    Comparative metabolic modelling is emerging as a novel field, supported by the development of reliable and standardized approaches for constructing genome-scale metabolic models in high throughput. New software solutions are needed to allow efficient comparative analysis of multiple models in the co

  18. Comparing trapezius muscle activity in the different planes of shoulder elevation.

    Science.gov (United States)

    Ishigaki, Tomonobu; Ishida, Tomoya; Samukawa, Mina; Saito, Hiroshi; Hirokawa, Motoki; Ezawa, Yuya; Sugawara, Makoto; Tohyama, Harukazu; Yamanaka, Masanori

    2015-05-01

    [Purpose] The purpose of this study was to compare the upper, middle, and lower trapezius muscles' activity in the different planes of shoulder elevation. [Subjects] Twenty male subjects volunteered for this study. [Methods] Surface electromyographic (EMG) activity for each of the three regions of the trapezius muscles in the three different planes of elevation were collected while the participants maintained 30, 60, and 90 degrees of elevation in each plane. The EMG data were normalized with maximum voluntary isometric contraction (%MVIC), and compared among the planes at each angle of elevation. [Results] There were significantly different muscle activities among the elevation planes at each angle. [Conclusion] This study found that the three regions of the trapezius muscles changed their activity depending on the planes of shoulder elevation. These changes in the trapezius muscles could induce appropriate scapular motion to face the glenoid cavity in the correct directions in different planes of shoulder elevation.

  19. Modeling Central Carbon Metabolic Processes in Soil Microbial Communities: Comparing Measured With Modeled

    Science.gov (United States)

    Dijkstra, P.; Fairbanks, D.; Miller, E.; Salpas, E.; Hagerty, S.

    2013-12-01

    Understanding the mechanisms regulating C cycling is hindered by our inability to directly observe and measure the biochemical processes of glycolysis, pentose phosphate pathway, and TCA cycle in intact and complex microbial communities. Position-specific 13C labeled metabolic tracer probing is proposed as a new way to study microbial community energy production, biosynthesis, C use efficiency (the proportion of substrate incorporated into microbial biomass), and enables the quantification of C fluxes through the central C metabolic network processes (Dijkstra et al 2011a,b). We determined the 13CO2 production from U-13C, 1-13C, 2-13C, 3-13C, 4-13C, 5-13C, and 6-13C labeled glucose and 1-13C and 2,3-13C pyruvate in parallel incubations in three soils along an elevation gradient. Qualitative and quantitative interpretation of the results indicate a high pentose phosphate pathway activity in soils. Agreement between modeled and measured CO2 production rates for the six C-atoms of 13C-labeled glucose indicate that the metabolic model used is appropriate for soil community processes, but that improvements can be made. These labeling and modeling techniques may improve our ability to analyze the biochemistry and (eco)physiology of intact microbial communities. Dijkstra, P., Blankinship, J.C., Selmants, P.C., Hart, S.C., Koch, G.W., Schwartz, E., Hungate, B.A., 2011a. Probing C flux patterns of soil microbial metabolic networks using parallel position-specific tracer labeling. Soil Biology & Biochemistry 43, 126-132. Dijkstra, P., Dalder, J.J., Selmants, P.C., Hart, S.C., Koch, G.W., Schwartz, E., Hungate, B.A., 2011b. Modeling soil metabolic processes using isotopologue pairs of position-specific 13C-labeled glucose and pyruvate. Soil Biology & Biochemistry 43, 1848-1857.

  20. ACTIVE AND PARTICIPATORY METHODS IN BIOLOGY: MODELING

    Directory of Open Access Journals (Sweden)

    Brînduşa-Antonela SBÎRCEA

    2011-01-01

    Full Text Available By using active and participatory methods it is hoped that pupils will not only come to a deeper understanding of the issues involved, but also that their motivation will be heightened. Pupil involvement in their learning is essential. Moreover, by using a variety of teaching techniques, we can help students make sense of the world in different ways, increasing the likelihood that they will develop a conceptual understanding. The teacher must be a good facilitator, monitoring and supporting group dynamics. Modeling is an instructional strategy in which the teacher demonstrates a new concept or approach to learning and pupils learn by observing. In the teaching of biology the didactic materials are fundamental tools in the teaching-learning process. Reading about scientific concepts or having a teacher explain them is not enough. Research has shown that modeling can be used across disciplines and in all grade and ability level classrooms. Using this type of instruction, teachers encourage learning.

  1. Activity based costing model for inventory valuation

    Directory of Open Access Journals (Sweden)

    Vineet Chouhan

    2017-03-01

    Full Text Available Activity-Based-Model (ABC is used for the purpose of significant improvement for overhead accounting systems by providing the best information required for managerial decision. This pa-per discusses implacability of ABC technique on inventory valuation as a management account-ing innovation. In order to prove the applicability of ABC for inventory control a material driven medium-sized and privately owned company from engineering (iron and steel industry is select-ed and by analysis of its production process and its material dependency and use of indirect in-ventory, an ABC model is explored for better inventory control. The case revealed that the ne-cessity of ABC in the area of inventory control is significant. The company is not only able to increase its quality of decision but also it can significantly analyze its cost of direct material cost, valuation of direct material and use its implications for better decision making.

  2. Comparing Domain-Specific Physical Activity Efficacy Level between Turkish Adolescent Girls and Boys

    Science.gov (United States)

    Çatikkas, Fatih

    2017-01-01

    The adolescence period is a very critical developmental period for personality, socializing and promotion of physical activity. In this regard, the aim of this study was to compare domain-specific physical activity efficacy level between adolescent boys and girls. A total of 219 girls (body weight: 57.50 ± 10.44 kg, height: 160.30 ± 7.40 cm, age…

  3. To evaluate and compare antidepressant activity of Rosa damascena in mice by using forced swimming test

    Directory of Open Access Journals (Sweden)

    Hemapriya Tirupathi

    2016-10-01

    Conclusions: Antidepressant activity of R. damascena was studied by forced swimming test in mice in the doses of 20 mg/kg and 40 mg/kg .This test shows that R. damascena significantly decreased the immobility time in mice. The results suggest that R. damascena has dose dependent antidepressant activity comparable with imipramine. [Int J Basic Clin Pharmacol 2016; 5(5.000: 1949-1952

  4. Comparative analysis of competitive activities of skilled players of different functions in women's and men's football

    Directory of Open Access Journals (Sweden)

    Zhurid S.

    2010-04-01

    Full Text Available The comparative analysis of results of the pedagogical looking is conducted after individual and command competition activity of footballers of professional clubs. The most characteristic are exposed technical tactical receptions. Quantitative and high-quality competition performance of sportsmen indicators are certain. In descriptions of competition activity it is necessary to take into account quantitative and high-quality indexes. Also are terms: speed, limitations, is in time and space, presence of hammerings together factors and competitor.

  5. Comparative study of the recommended methodologies by CLSI and EUCAST for activity evaluation antifungal

    OpenAIRE

    2009-01-01

    The international organizations CLSI and EUCAST developed reference methodologies for activity evaluation antifungal. The aim of this work was to compare the recommended methodologies by the CLSI and EUCAST in the antifungal activity evaluation of crude extracts of Azadirachta indica and green propolis. The results showed that the MIC values determined by the EUCAST methodology were smaller than that determined by the CLSI. Nevertheless, both methodologies were satisfactory to detect and eval...

  6. Data correction for seven activity trackers based on regression models.

    Science.gov (United States)

    Andalibi, Vafa; Honko, Harri; Christophe, Francois; Viik, Jari

    2015-08-01

    Using an activity tracker for measuring activity-related parameters, e.g. steps and energy expenditure (EE), can be very helpful in assisting a person's fitness improvement. Unlike the measuring of number of steps, an accurate EE estimation requires additional personal information as well as accurate velocity of movement, which is hard to achieve due to inaccuracy of sensors. In this paper, we have evaluated regression-based models to improve the precision for both steps and EE estimation. For this purpose, data of seven activity trackers and two reference devices was collected from 20 young adult volunteers wearing all devices at once in three different tests, namely 60-minute office work, 6-hour overall activity and 60-minute walking. Reference data is used to create regression models for each device and relative percentage errors of adjusted values are then statistically compared to that of original values. The effectiveness of regression models are determined based on the result of a statistical test. During a walking period, EE measurement was improved in all devices. The step measurement was also improved in five of them. The results show that improvement of EE estimation is possible only with low-cost implementation of fitting model over the collected data e.g. in the app or in corresponding service back-end.

  7. Inferring brain-computational mechanisms with models of activity measurements.

    Science.gov (United States)

    Kriegeskorte, Nikolaus; Diedrichsen, Jörn

    2016-10-01

    High-resolution functional imaging is providing increasingly rich measurements of brain activity in animals and humans. A major challenge is to leverage such data to gain insight into the brain's computational mechanisms. The first step is to define candidate brain-computational models (BCMs) that can perform the behavioural task in question. We would then like to infer which of the candidate BCMs best accounts for measured brain-activity data. Here we describe a method that complements each BCM by a measurement model (MM), which simulates the way the brain-activity measurements reflect neuronal activity (e.g. local averaging in functional magnetic resonance imaging (fMRI) voxels or sparse sampling in array recordings). The resulting generative model (BCM-MM) produces simulated measurements. To avoid having to fit the MM to predict each individual measurement channel of the brain-activity data, we compare the measured and predicted data at the level of summary statistics. We describe a novel particular implementation of this approach, called probabilistic representational similarity analysis (pRSA) with MMs, which uses representational dissimilarity matrices (RDMs) as the summary statistics. We validate this method by simulations of fMRI measurements (locally averaging voxels) based on a deep convolutional neural network for visual object recognition. Results indicate that the way the measurements sample the activity patterns strongly affects the apparent representational dissimilarities. However, modelling of the measurement process can account for these effects, and different BCMs remain distinguishable even under substantial noise. The pRSA method enables us to perform Bayesian inference on the set of BCMs and to recognize the data-generating model in each case.This article is part of the themed issue 'Interpreting BOLD: a dialogue between cognitive and cellular neuroscience'.

  8. Inferring brain-computational mechanisms with models of activity measurements

    Science.gov (United States)

    Diedrichsen, Jörn

    2016-01-01

    High-resolution functional imaging is providing increasingly rich measurements of brain activity in animals and humans. A major challenge is to leverage such data to gain insight into the brain's computational mechanisms. The first step is to define candidate brain-computational models (BCMs) that can perform the behavioural task in question. We would then like to infer which of the candidate BCMs best accounts for measured brain-activity data. Here we describe a method that complements each BCM by a measurement model (MM), which simulates the way the brain-activity measurements reflect neuronal activity (e.g. local averaging in functional magnetic resonance imaging (fMRI) voxels or sparse sampling in array recordings). The resulting generative model (BCM-MM) produces simulated measurements. To avoid having to fit the MM to predict each individual measurement channel of the brain-activity data, we compare the measured and predicted data at the level of summary statistics. We describe a novel particular implementation of this approach, called probabilistic representational similarity analysis (pRSA) with MMs, which uses representational dissimilarity matrices (RDMs) as the summary statistics. We validate this method by simulations of fMRI measurements (locally averaging voxels) based on a deep convolutional neural network for visual object recognition. Results indicate that the way the measurements sample the activity patterns strongly affects the apparent representational dissimilarities. However, modelling of the measurement process can account for these effects, and different BCMs remain distinguishable even under substantial noise. The pRSA method enables us to perform Bayesian inference on the set of BCMs and to recognize the data-generating model in each case. This article is part of the themed issue ‘Interpreting BOLD: a dialogue between cognitive and cellular neuroscience’. PMID:27574316

  9. Comparative in vitro activity of ceftobiprole against Gram-positive cocci.

    Science.gov (United States)

    Betriu, Carmen; Culebras, Esther; Gómez, María; López-Fabal, Fátima; Rodríguez-Avial, Iciar; Picazo, Juan J

    2010-08-01

    The activity of ceftobiprole and comparator agents was evaluated against a collection of 880 isolates, comprising 200 meticillin-susceptible Staphylococcus aureus, 200 meticillin-resistant S. aureus, 180 coagulase-negative staphylococci blood isolates, 100 Streptococcuspneumoniae and 200 macrolide-resistant beta-haemolytic streptococci (100 Streptococcus pyogenes and 100 Streptococcus agalactiae). Ceftobiprole showed excellent activity against staphylococci (minimum inhibitory concentrations Ceftobiprole was also highly active against penicillin-resistant S. pneumoniae and macrolide-resistant beta-haemolytic streptococci, inhibiting 99.6% of all streptococci tested at ceftobiprole appears to be a promising agent for the treatment of infections caused by multidrug-resistant Gram-positive pathogens.

  10. Modeling Nonlinear Power Amplifiers in OFDM Systems from Subsampled Data: A Comparative Study Using Real Measurements

    Directory of Open Access Journals (Sweden)

    Santamaría Ignacio

    2003-01-01

    Full Text Available A comparative study among several nonlinear high-power amplifier (HPA models using real measurements is carried out. The analysis is focused on specific models for wideband OFDM signals, which are known to be very sensitive to nonlinear distortion. Moreover, unlike conventional techniques, which typically use a single-tone test signal and power measurements, in this study the models are fitted using subsampled time-domain data. The in-band and out-of-band (spectral regrowth performances of the following models are evaluated and compared: Saleh's model, envelope polynomial model (EPM, Volterra model, the multilayer perceptron (MLP model, and the smoothed piecewise-linear (SPWL model. The study shows that the SPWL model provides the best in-band characterization of the HPA. On the other hand, the Volterra model provides a good trade-off between model complexity (number of parameters and performance.

  11. An approach for activity-based DEVS model specification

    DEFF Research Database (Denmark)

    Alshareef, Abdurrahman; Sarjoughian, Hessam S.; Zarrin, Bahram

    2016-01-01

    activity-based behavior modeling of parallel DEVS atomic models. We consider UML activities and actions as fundamental units of behavior modeling, especially in the presence of recent advances in the UML 2.5 specifications. We describe in detail how to approach activity modeling with a set of elemental...

  12. Antimicrobial activity and chemometric modelling of South African propolis.

    Science.gov (United States)

    Suleman, T; van Vuuren, S; Sandasi, M; Viljoen, A M

    2015-10-01

    This study reports on the inhibitory and bactericidal properties of 39 South African (SA) propolis samples and three propolis samples from Brazil. Ethanolic extracts of propolis (EEP) were prepared and their antimicrobial activities tested using the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) assays. Some samples displayed substantial antimicrobial activity with MIC and MBC values as low as 6 μg ml(-1) against Staphylococcus aureus. The correlation between liquid chromatography-mass spectrometry (LC-MS) chemical data and the antimicrobial activity of propolis extracts was investigated using multivariate data analysis tools. Orthogonal projections to latent structures (OPLS) models were created for the two Gram-positive bacteria (Enterococcus faecalis and S. aureus) and Candida albicans. Using the S-plot function, it was possible to identify the bioactive constituents in propolis as chrysin, pinocembrin, galangin and pinobanksin-3-O-acetate. The SA propolis samples tested displayed noteworthy antimicrobial activity, favourably comparable to that of the Brazilian comparator and 'gold standard'. The observed antimicrobial activity of SA propolis can possibly be attributed to its flavonoid content. Based on the good antimicrobial activity observed for SA propolis, this natural resource shows promise and should be considered for development which may contribute to growing the bio-economy in the region. © 2015 The Society for Applied Microbiology.

  13. Mathematical Modeling of Metal Active Gas (MAG) Arc Welding

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    In the present paper, a numerical model for MAG (metal active gas) arc welding of thin plate has been developed. In MAG arc welding, the electrode wire is melted and supplied into the molten pool intermittently. Accordingly, it is assumed on the modeling that the thermal energy enters the base-plates through two following mechanisms, i.e., direct heating from arc plasma and “indirect” heating from the deposited metal. In the second part of the paper, MAG arc welding process is numerically analyzed by using the model, and the calculated weld bead dimension and surface profile have been compared with the experimental MAG welds on steel plate. As the result, it is made clear that the model is capable of predicting the bead profile of thin-plate MAG arc welding , including weld bead with undercutting.

  14. Support Vector Machine active learning for 3D model retrieval

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    In this paper, we present a novel Support Vector Machine active learning algorithm for effective 3D model retrieval using the concept of relevance feedback. The proposed method learns from the most informative objects which are marked by the user, and then creates a boundary separating the relevant models from irrelevant ones. What it needs is only a small number of 3D models labelled by the user. It can grasp the user's semantic knowledge rapidly and accurately. Experimental results showed that the proposed algorithm significantly improves the retrieval effectiveness. Compared with four state-of-the-art query refinement schemes for 3D model retrieval, it provides superior retrieval performance after no more than two rounds of relevance feedback.

  15. Comparing Book- and Tablet-Based Picture Activity Schedules: Acquisition and Preference.

    Science.gov (United States)

    Giles, Aimee; Markham, Victoria

    2017-09-01

    Picture activity schedules consist of a sequence of images representing the order of tasks for a person to complete. Although, picture activity schedules have traditionally been presented in a book format, recently picture activity schedules have been evaluated on technological devices such as an iPod™ touch. The present study compared the efficiency of picture activity schedule acquisition on book- and tablet-based modalities. In addition, participant preference for each modality was assessed. Three boys aged below 5 years with a diagnosis of autism participated. Participants were taught to follow the schedules using both modalities. Following mastery of each modality of picture activity schedule, a concurrent-chains preference assessment was conducted to evaluate participant preference for each modality. Differences in acquisition rates across the two modalities were marginal. Preference for book- or tablet-based schedules was idiosyncratic across participants.

  16. MODBASE: a database of annotated comparative protein structure models and associated resources

    OpenAIRE

    Pieper, Ursula; Eswar, Narayanan; Davis, Fred P.; Braberg, Hannes; Madhusudhan, M. S.; Rossi, Andrea; Marti-Renom, Marc; Karchin, Rachel; Webb, Ben M.; Eramian, David; Shen, Min-Yi; Kelly, Libusha; Melo, Francisco; Sali, Andrej

    2005-01-01

    MODBASE () is a database of annotated comparative protein structure models for all available protein sequences that can be matched to at least one known protein structure. The models are calculated by MODPIPE, an automated modeling pipeline that relies on MODELLER for fold assignment, sequence–structure alignment, model building and model assessment (). MODBASE is updated regularly to reflect the growth in protein sequence and structure databases, and improvements in the software for calculat...

  17. Theory and modeling of active brazing.

    Energy Technology Data Exchange (ETDEWEB)

    van Swol, Frank B.; Miller, James Edward; Lechman, Jeremy B.; Givler, Richard C.

    2013-09-01

    Active brazes have been used for many years to produce bonds between metal and ceramic objects. By including a relatively small of a reactive additive to the braze one seeks to improve the wetting and spreading behavior of the braze. The additive modifies the substrate, either by a chemical surface reaction or possibly by alloying. By its nature, the joining process with active brazes is a complex nonequilibrium non-steady state process that couples chemical reaction, reactant and product diffusion to the rheology and wetting behavior of the braze. Most of the these subprocesses are taking place in the interfacial region, most are difficult to access by experiment. To improve the control over the brazing process, one requires a better understanding of the melting of the active braze, rate of the chemical reaction, reactant and product diffusion rates, nonequilibrium composition-dependent surface tension as well as the viscosity. This report identifies ways in which modeling and theory can assist in improving our understanding.

  18. Active-beam cross-sectional modeling

    Science.gov (United States)

    Cesnik, Carlos E. S.; Ortega-Morales, Miguel

    2000-06-01

    A finite-element based analysis for modeling active composite beams with embedded anisotropic actuation is presented. It is derived from three-dimensional electroelasticity, where the original problem is reduced via the variational asymptotic method. The resulting cross-sectional analysis takes into consideration passive and active anisotropic and nonhomogeneous materials, and represents general (thin-walled, thick-walled, solid) cross-sectional geometries. The formulation requires neither the costly use of 3-D finite element discretization nor the loss of accuracy inherent to any simplified representation of the cross section. The developed formulation is numerically implemented in VABS-A, and several numerical and experimental tests cases are used to support validation of the proposed theory. Also, the effect of the presence of a core in originally hallow configurations is presented and counter-intuitive conclusions are discussed. The generality of the method and accuracy of the results increase confidence at the design stage that the active beam structure will perform as expected and, consequently, should lower costs from experimental tests and further adjustments.

  19. Models of the stochastic activity of neurones

    CERN Document Server

    Holden, Arun Vivian

    1976-01-01

    These notes have grown from a series of seminars given at Leeds between 1972 and 1975. They represent an attempt to gather together the different kinds of model which have been proposed to account for the stochastic activity of neurones, and to provide an introduction to this area of mathematical biology. A striking feature of the electrical activity of the nervous system is that it appears stochastic: this is apparent at all levels of recording, ranging from intracellular recordings to the electroencephalogram. The chapters start with fluctuations in membrane potential, proceed through single unit and synaptic activity and end with the behaviour of large aggregates of neurones: L have chgaen this seque~~e\\/~~';uggest that the interesting behaviourr~f :the nervous system - its individuality, variability and dynamic forms - may in part result from the stochastic behaviour of its components. I would like to thank Dr. Julio Rubio for reading and commenting on the drafts, Mrs. Doris Beighton for producing the fin...

  20. Jackson System Development, Entity-relationship Analysis and Data Flow Models: a comparative study

    NARCIS (Netherlands)

    Wieringa, R.J.

    1994-01-01

    This report compares JSD with ER modeling and data flow modeling. It is shown that JSD can be combined with ER modeling and that the result is a richer method than either of the two. The resulting method can serve as a basis for a pratical object-oriented modeling method and has some resemblance to

  1. A Comparative Structural Equation Modeling Investigation of the Relationships among Teaching, Cognitive and Social Presence

    Science.gov (United States)

    Kozan, Kadir

    2016-01-01

    The present study investigated the relationships among teaching, cognitive, and social presence through several structural equation models to see which model would better fit the data. To this end, the present study employed and compared several different structural equation models because different models could fit the data equally well. Among…

  2. Jackson System Development, Entity-relationship Analysis and Data Flow Models: a comparative study

    NARCIS (Netherlands)

    Wieringa, Roelf J.

    1994-01-01

    This report compares JSD with ER modeling and data flow modeling. It is shown that JSD can be combined with ER modeling and that the result is a richer method than either of the two. The resulting method can serve as a basis for a pratical object-oriented modeling method and has some resemblance to

  3. Comparing of four IRT models when analyzing two tests for inductive reasoning

    NARCIS (Netherlands)

    de Koning, E.; Sijtsma, K.; Hamers, J.H.M.

    2002-01-01

    This article discusses the use of the nonparametric IRT Mokken models of monotone homogeneity and double monotonicity and the parametric Rasch and Verhelst models for the analysis of binary test data. First, the four IRT models are discussed and compared at the theoretical level, and for each model,

  4. Combining docking and comparative molecular similarity indices analysis (COMSIA) to predict estrogen activity and probe molecular mechanisms of estrogen activity for estrogen compounds

    Institute of Scientific and Technical Information of China (English)

    YANG XuShu; WANG XiaoDong; JI Li; LI Rong; SUN Cheng; WANG LianSheng

    2008-01-01

    Estrogen compounds are suspected of disrupting endocrine functions by mimicking natural hormones,and such compounds may pose a serious threat to the health of humans and wildlife. Close attention has been paid to the prediction and molecular mechanisms of estrogen activity for estrogen compounds. In this article, estrogen receptor a subtype (Era) -based comparative molecular similarity indices analysis (COMSIA) was performed on 44 estrogen compounds with structural diversity to find out the structural relationship with the activity and to predict the activity. The model with the significant correlation and the best predictive power (R2 = 0.965, (Q2LOO = 0.599, R2pred = 0.825) was achieved. The COMSIA and docking results revealed the structural features for estrogen activity and key amino acid residues in binding pocket, and provided an insight into the interaction between the ligands and these amino acid residues.

  5. Category activation effects in judgment and behaviour: the moderating role of perceived comparability.

    Science.gov (United States)

    Aarts, Henk; Dijksterhuis, Ap

    2002-03-01

    Previous research on category activation effects demonstrates that extreme exemplar priming can lead to contrast effects as well as assimilation effects in target judgments. Two experiments extended this line of research by investigating the moderating role of perceived comparability, that is, the extent to which the exemplar and target are believed to belong to the same category and thus can be compared. In both experiments, participants judged the speed of a person displayed on a picture following priming with animals exemplifying either extreme speed ('cheetah') or extreme slowness ('turtle'). In addition, in the second experiment a behavioural measure was included. In the first experiment individual differences concerning the perceived comparability between animals and humans were assessed. In the second experiment perceived comparability was experimentally varied. Results showed that the direction of category activation effects (i.e. assimilation versus contrast) depended on the extent to which the prime and target categories were seen as comparable. Contrast effects on both judgments and behaviour emerged when the prime and the target category were perceived as comparable. However, assimilation effects on judgment and behaviour ensued when the prime and target category were not perceived as comparable.

  6. A Comparative Study of Neural Networks and Fuzzy Systems in Modeling of a Nonlinear Dynamic System

    Directory of Open Access Journals (Sweden)

    Metin Demirtas

    2011-07-01

    Full Text Available The aim of this paper is to compare the neural networks and fuzzy modeling approaches on a nonlinear system. We have taken Permanent Magnet Brushless Direct Current (PMBDC motor data and have generated models using both approaches. The predictive performance of both methods was compared on the data set for model configurations. The paper describes the results of these tests and discusses the effects of changing model parameters on predictive and practical performance. Modeling sensitivity was used to compare for two methods.

  7. Screening of Plant Extracts for Antioxidant Activity: a Comparative Study on Three Testing Methods

    NARCIS (Netherlands)

    Koleva, I.; Beek, van T.A.; Linssen, J.P.H.; Groot, de Æ.; Evstatieva, L.N.

    2002-01-01

    Three methods widely employed in the evaluation of antioxidant activity, namely 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging method, static headspace gas chromatography (HS-GC) and -carotene bleaching test (BCBT), have been compared with regard to their application in the screening of pla

  8. [The comparative investigation of antihypoxia activity of glutamic and N-acetylglutamic acids].

    Science.gov (United States)

    Makarova, L M; Pogorelyĭ, V E

    2013-01-01

    Comparative study of antihypoxic activity of glutamic and N-acetylglutamic acid in doses of 1, 10, 50 and 100 mg/kg was realized. It was experimentally ascertained that the most apparent antihypoxic action of study objects occurs in conditions of hypobaric hypoxia of acetylated derivative of glutamic acid considerably exceeds glutamic acid.

  9. Comparative in vitro activity of ceftobiprole against staphylococci displaying normal and small-colony variant phenotypes

    NARCIS (Netherlands)

    von Eiff, Christof; Friedrich, Alexander W.; Becker, Karsten; Peters, Georg

    2005-01-01

    The antistaphylococcal activity of ceftobiprole was compared with those of cefuroxime, linezolid, and moxifloxacin by using the agar dilution method. Apart from three strains with small-colony variant phenotypes, all Staphylococcus aureus isolates tested were inhibited by < or =2 microg/ml of ceftob

  10. Physical activity assessment in patients with axial spondyloarthritis compared to healthy controls: a technology-based approach.

    Directory of Open Access Journals (Sweden)

    Thijs Willem Swinnen

    Full Text Available INTRODUCTION: Traditionally, assessment in axial Spondyloarthritis (aSpA includes the evaluation of the capacity to execute tasks, conceptualized as physical function. The role of physical activity, defined as movement-related energy expenditure, is largely unknown and almost exclusively studied using patient-reported outcome measures. The aims of this observational cross-sectional study are to compare physical activity between patients with aSpA and healthy controls (HC and to evaluate the contribution of disease activity to physical activity differences between groups. METHODS: Forty patients with aSpA were matched by age, gender, period of data acquisition in terms of days and season to 40 HC. Physical activity was measured during five consecutive days (three weekdays and two weekend days using ambulatory monitoring (SenseWear Armband. Self-reported disease activity was measured by the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI. Differences in physical activity between patients with aSpA and HC were examined with Wilcoxon signed-rank tests and a mixed linear model. Difference scores between patients and HC were correlated with disease activity. RESULTS: Average weekly physical activity level (Med(IQR; HC:1.54(1.41-1.73; aSpA:1.45(1.31-1.67,MET and energy expenditure (HC:36.40(33.43-41.01; aSpA:34.55(31.08-39.41,MET.hrs/day were significantly lower in patients with aSpA. Analyses across intensity levels revealed no significant differences between groups for inactivity and time spent at light or moderate physical activities. In contrast, weekly averages of vigorous (HC:4.02(1.20-12.60; aSpA:0.00(0.00-1.20,min/d, very vigorous physical activities (HC0.00(0.00-1.08; aSpA:0.00(0.00-0.00,mind/d and moderate/(veryvigorous combined (HC2.41(1.62-3.48; aSpA:1.63(1.20-2.82,hrs/d were significantly lower in patients with aSpA. Disease activity did not interact with differences in physical activity between patients with aSpA and HC

  11. Comparative modeling of biological nutrient removal from landfill leachate using a circulating fluidized bed bioreactor (CFBBR).

    Science.gov (United States)

    Eldyasti, Ahmed; Andalib, Mehran; Hafez, Hisham; Nakhla, George; Zhu, Jesse

    2011-03-15

    Steady state operational data from a pilot scale circulating fluidized bed bioreactor (CFBBR) during biological treatment of landfill leachate, at empty bed contact times (EBCTs) of 0.49, and 0.41 d and volumetric nutrients loading rates of 2.2-2.6 kg COD/(m(3)d), 0.7-0.8 kg N/(m(3)d), and 0.014-0.016 kg P/(m(3)d), was used to calibrate and compare developed process models in BioWin(®) and AQUIFAS(®). BioWin(®) and AQUIFAS(®) were both capable of predicting most of the performance parameters such as effluent TKN, NH(4)-N, NO(3)-N, TP, PO(4)-P, TSS, and VSS with an average percentage error (APE) of 0-20%. BioWin(®) underpredicted the effluent BOD and SBOD values for various runs by 80% while AQUIFAS(®) predicted effluent BOD and SBOD with an APE of 50%. Although both calibrated models, confirmed the advantages of the CFBBR technology in treating the leachate of high volumetric loading and low biomass yields due to the long solid retention time (SRT), both BioWin(®) and AQUIFAS(®) predicted the total biomass and SRT of CFBBR based on active biomass only, whereas in the CFBBR runs both active as well as inactive biomass accumulated.

  12. A comparative modeling and molecular docking study on Mycobacterium tuberculosis targets involved in peptidoglycan biosynthesis.

    Science.gov (United States)

    Fakhar, Zeynab; Naiker, Suhashni; Alves, Claudio N; Govender, Thavendran; Maguire, Glenn E M; Lameira, Jeronimo; Lamichhane, Gyanu; Kruger, Hendrik G; Honarparvar, Bahareh

    2016-11-01

    An alarming rise of multidrug-resistant Mycobacterium tuberculosis strains and the continuous high global morbidity of tuberculosis have reinvigorated the need to identify novel targets to combat the disease. The enzymes that catalyze the biosynthesis of peptidoglycan in M. tuberculosis are essential and noteworthy therapeutic targets. In this study, the biochemical function and homology modeling of MurI, MurG, MraY, DapE, DapA, Alr, and Ddl enzymes of the CDC1551 M. tuberculosis strain involved in the biosynthesis of peptidoglycan cell wall are reported. Generation of the 3D structures was achieved with Modeller 9.13. To assess the structural quality of the obtained homology modeled targets, the models were validated using PROCHECK, PDBsum, QMEAN, and ERRAT scores. Molecular dynamics simulations were performed to calculate root mean square deviation (RMSD) and radius of gyration (Rg) of MurI and MurG target proteins and their corresponding templates. For further model validation, RMSD and Rg for selected targets/templates were investigated to compare the close proximity of their dynamic behavior in terms of protein stability and average distances. To identify the potential binding mode required for molecular docking, binding site information of all modeled targets was obtained using two prediction algorithms. A docking study was performed for MurI to determine the potential mode of interaction between the inhibitor and the active site residues. This study presents the first accounts of the 3D structural information for the selected M. tuberculosis targets involved in peptidoglycan biosynthesis.

  13. Structure-activity models for contact sensitization.

    Science.gov (United States)

    Fedorowicz, Adam; Singh, Harshinder; Soderholm, Sidney; Demchuk, Eugene

    2005-06-01

    Allergic contact dermatitis (ACD) is a widespread cause of workers' disabilities. Although some substances found in the workplace are rigorously tested, the potential of the vast majority of chemicals to cause skin sensitization remains unknown. At the same time, exhaustive testing of all chemicals in workplaces is costly and raises ethical concerns. New approaches to developing information for risk assessment based on computational (quantitative) structure-activity relationship [(Q)SAR] methods may be complementary to and reduce the need for animal testing. Virtually any number of existing, de novo, and even preconceived compounds can be screened in silico at a fraction of the cost of animal testing. This work investigates the utility of ACD (Q)SAR modeling from the occupational health perspective using two leading software products, DEREK for Windows and TOPKAT, and an original method based on logistic regression methodology. It is found that the correct classification of (Q)SAR predictions for guinea pig data achieves values of 73.3, 82.9, and 87.6% for TOPKAT, DEREK for Windows, and the logistic regression model, respectively. The correct classification using LLNA data equals 73.0 and 83.2% for DEREK for Windows and the logistic regression model, respectively.

  14. Comparative study of proton pump inhibitors on dexamethasone plus pylorus ligation induced ulcer model in rats

    Directory of Open Access Journals (Sweden)

    Thippeswamy A. H. M.

    2010-01-01

    Full Text Available The present study was designed to compare ulcer protective effect of proton pump inhibitors viz. omeprazole, rabeprazole and lansoprazole against dexamethasone plus pylorus ligation induced ulcer model. Dexamethasone (5 mg/kg was used as an ulcerogen. Dexamethasone suspended in 1% CMC in water was given orally to all the rats 15 min after the pylorus ligation. Omeprazole (20 mg/kg, rabeprazole (20 mg/kg, and lansoprazole (20 mg/kg were administered by oral route 30 min prior to ligation was used for ulcer protective studies, gastric secretion and mucosal studies. Effects of proton pump inhibitors were determined by the evaluation of various biochemical parameters such as ulcer index, free and total acidity, gastric pH, mucin, pepsin and total proteins. Oral administration of proton pump inhibitors showed significant reduction in gastric acid secretion and ulcer protective activity against dexamethasone plus pylorus ligation induced ulcer model. The % protection of omeprazole, rabeprazole and lansoprazole was 84.04, 89.36 and 79.78, respectively. Rabeprazole significantly inhibited the acid-pepsin secretion and increased the gastric mucin secretion. The observations made in the present study suggest that rabeprazole is the most effective gastric antisecretory and ulcer healing agent as compared to omeprazole and lansoprazole.

  15. Comparative study of the endocrine-disrupting activity of bisphenol A and 19 related compounds.

    Science.gov (United States)

    Kitamura, Shigeyuki; Suzuki, Tomoharu; Sanoh, Seigo; Kohta, Ryuki; Jinno, Norimasa; Sugihara, Kazumi; Yoshihara, Shin'ichi; Fujimoto, Nariaki; Watanabe, Hiromitsu; Ohta, Shigeru

    2005-04-01

    The endocrine-disrupting activities of bisphenol A (BPA) and 19 related compounds were comparatively examined by means of different in vitro and in vivo reporter assays. BPA and some related compounds exhibited estrogenic activity in human breast cancer cell line MCF-7, but there were remarkable differences in activity. Tetrachlorobisphenol A (TCBPA) showed the highest activity, followed by bisphenol B, BPA, and tetramethylbisphenol A (TMBPA); 2,2-bis(4-hydroxyphenyl)-1-propanol, 1,1-bis(4-hydroxyphenyl)propionic acid and 2,2-diphenylpropane showed little or no activity. Anti-estrogenic activity against 17beta-estradiol was observed with TMBPA and tetrabromobisphenol A (TBBPA). TCBPA, TBBPA, and BPA gave positive responses in the in vivo uterotrophic assay using ovariectomized mice. In contrast, BPA and some related compounds showed significant inhibitory effects on the androgenic activity of 5alpha-dihydrotestosterone in mouse fibroblast cell line NIH3T3. TMBPA showed the highest antagonistic activity, followed by bisphenol AF, bisphenol AD, bisphenol B, and BPA. However, TBBPA, TCBPA, and 2,2-diphenylpropane were inactive. TBBPA, TCBPA, TMBPA, and 3,3'-dimethylbisphenol A exhibited significant thyroid hormonal activity towards rat pituitary cell line GH3, which releases growth hormone in a thyroid hormone-dependent manner. However, BPA and other derivatives did not show such activity. The results suggest that the 4-hydroxyl group of the A-phenyl ring and the B-phenyl ring of BPA derivatives are required for these hormonal activities, and substituents at the 3,5-positions of the phenyl rings and the bridging alkyl moiety markedly influence the activities.

  16. Comparative Study of SSVEP- and P300-Based Models for the Telepresence Control of Humanoid Robots.

    Directory of Open Access Journals (Sweden)

    Jing Zhao

    Full Text Available In this paper, we evaluate the control performance of SSVEP (steady-state visual evoked potential- and P300-based models using Cerebot-a mind-controlled humanoid robot platform. Seven subjects with diverse experience participated in experiments concerning the open-loop and closed-loop control of a humanoid robot via brain signals. The visual stimuli of both the SSVEP- and P300- based models were implemented on a LCD computer monitor with a refresh frequency of 60 Hz. Considering the operation safety, we set the classification accuracy of a model over 90.0% as the most important mandatory for the telepresence control of the humanoid robot. The open-loop experiments demonstrated that the SSVEP model with at most four stimulus targets achieved the average accurate rate about 90%, whereas the P300 model with the six or more stimulus targets under five repetitions per trial was able to achieve the accurate rates over 90.0%. Therefore, the four SSVEP stimuli were used to control four types of robot behavior; while the six P300 stimuli were chosen to control six types of robot behavior. Both of the 4-class SSVEP and 6-class P300 models achieved the average success rates of 90.3% and 91.3%, the average response times of 3.65 s and 6.6 s, and the average information transfer rates (ITR of 24.7 bits/min 18.8 bits/min, respectively. The closed-loop experiments addressed the telepresence control of the robot; the objective was to cause the robot to walk along a white lane marked in an office environment using live video feedback. Comparative studies reveal that the SSVEP model yielded faster response to the subject's mental activity with less reliance on channel selection, whereas the P300 model was found to be suitable for more classifiable targets and required less training. To conclude, we discuss the existing SSVEP and P300 models for the control of humanoid robots, including the models proposed in this paper.

  17. Comparative Study of SSVEP- and P300-Based Models for the Telepresence Control of Humanoid Robots.

    Science.gov (United States)

    Zhao, Jing; Li, Wei; Li, Mengfan

    2015-01-01

    In this paper, we evaluate the control performance of SSVEP (steady-state visual evoked potential)- and P300-based models using Cerebot-a mind-controlled humanoid robot platform. Seven subjects with diverse experience participated in experiments concerning the open-loop and closed-loop control of a humanoid robot via brain signals. The visual stimuli of both the SSVEP- and P300- based models were implemented on a LCD computer monitor with a refresh frequency of 60 Hz. Considering the operation safety, we set the classification accuracy of a model over 90.0% as the most important mandatory for the telepresence control of the humanoid robot. The open-loop experiments demonstrated that the SSVEP model with at most four stimulus targets achieved the average accurate rate about 90%, whereas the P300 model with the six or more stimulus targets under five repetitions per trial was able to achieve the accurate rates over 90.0%. Therefore, the four SSVEP stimuli were used to control four types of robot behavior; while the six P300 stimuli were chosen to control six types of robot behavior. Both of the 4-class SSVEP and 6-class P300 models achieved the average success rates of 90.3% and 91.3%, the average response times of 3.65 s and 6.6 s, and the average information transfer rates (ITR) of 24.7 bits/min 18.8 bits/min, respectively. The closed-loop experiments addressed the telepresence control of the robot; the objective was to cause the robot to walk along a white lane marked in an office environment using live video feedback. Comparative studies reveal that the SSVEP model yielded faster response to the subject's mental activity with less reliance on channel selection, whereas the P300 model was found to be suitable for more classifiable targets and required less training. To conclude, we discuss the existing SSVEP and P300 models for the control of humanoid robots, including the models proposed in this paper.

  18. Protocol: Entrepreneurship in the area of Marketing. Comparing PBL vs active lectures

    Directory of Open Access Journals (Sweden)

    Virginia Rincón Diez

    2017-06-01

    Full Text Available This protocol presents a research process which aims to analyze the impact of an active learning model on entrepreneurship of university students of Marketing. First, a learning model is proposed which allows to jointly conducting the content of different subjects and which provides an integrated vision of Marketing. Subsequently, the concept of entrepreneurship is defined and a measuring instrument is mentioned. Through this instrument the information needed to analyze to what extent the new learning model promotes students’ entrepreneurship is gathered. Finally, several possibilities to perform the data analysis are presented.

  19. Inhibition of pancreatic lipase by black tea theaflavins: Comparative enzymology and in silico modeling studies.

    Science.gov (United States)

    Glisan, Shannon L; Grove, Kimberly A; Yennawar, Neela H; Lambert, Joshua D

    2017-02-01

    Few studies have examined the effect of black tea (Camellia sinensis) theaflavins on obesity-related targets. Pancreatic lipase (PL) plays a central role in fat metabolism and is a validated target for weight loss. We compared the inhibitory efficacy of individual theaflavins and explored the underlying mechanism. Theaflavin-3,3'-digallate (TFdiG), theaflavin-3'-gallate, theaflavin-3-gallate, and theaflavin inhibited PL with IC50 of 1.9, 4.2, 3.0, and >10μmol/L. The presence and location of the galloyl ester moiety were essential for inhibitory potency. TFdiG exhibited mixed inhibition with respect to substrate concentration. In silico modeling showed that theaflavins bind to Asn263 and Asp206, which form a pocket adjacent to the active site, and galloyl-containing theaflavins are then predicted to perturb the protonation of His264. These data provide a putative mechanism to explain the anti-obesity effects of tea.

  20. [Comparative analysis of activity of different promoters for NIS gene expression in melanoma cells].

    Science.gov (United States)

    Kuz'mich, A I; Kopantsev, E P; Vinogradova, T V; Sverdlov, E D

    2014-01-01

    Development of targeted drug delivery system is key problem of cancer gene therapy. To ensure specific delivery of these therapeutic compounds to the tumor it is preferable for therapeutic gene expression to occur predominantly in cancer cells. Therefore, when testing drug in vivo, it is necessary to study distribution of therapeutic gene expression products in different tissues of the organism. Sodium iodide symporter (NIS) is attractive reporter because its tissue level is easily quantitatively detected by noninvasive imaging methods. Different promoters are used to direct expression of therapeutic genes in tumor cells: strong nonspecific, moderate tissue-specific and tumor-specific. Tumor-specific promoters function in wide range of tumor cells, however they are relatively weak. Relationship between promoter and sodium iodide symporter activity is unclear to date. In this report we examined activity of different promoters in two melanoma cell lines, functional activity of NIS driven by these promoters, also we compared promoter strength and NIS activity. We demonstrated that in spite of strong differences in promoter activity functional activity of NIS directed by these promoters varies weakly. Relatively weak melanoma-specific promoter directs high NIS activity in melanoma cell, however weaker cancer-specific promoters drive high NIS activity only in certain melanoma cell line.

  1. Comparing Levels of Depression in Healthy Active and Inactive Elders versus Those with Knee Osteoarthritis Disease

    Directory of Open Access Journals (Sweden)

    Amir Shams

    2016-04-01

    Full Text Available Knee osteoarthritis can have negative effects on the physical and mental conditions, social and family relations, general health and positive feelings of elders. For example, severe limitation of motion and increased depression, which are results of this disease, can have negative impacts on elders. The purpose of this study was to compare the levels of depression in healthy active and inactive elders versus those with knee osteoarthritis disease. Two hundred and twenty (220 elders with knee osteoarthritis disease (110 active and 110 inactive patients and 220 healthy elders (110 active and 110 inactive were voluntarily selected, and they filled the questionnaire about elders’ personal characteristics, physical activity and depression levels. Four groups had differences with respect to education, age and gender. The results of chi-square test revealed that women with knee osteoarthritis disease had increased levels of depression compared to men with the same condition (p<0.05. Older patients had increased levels of depression and educated elders reported lower levels of depression. The results of the one way analysis of variance (ANOVA revealed that there exist a significant difference in depression scores of healthy active and healthy inactive elders and those with knee osteoarthritis disease. The results of Tukey’s test revealed that healthy active elder had lower depression scores compared to inactive elders with knee osteoarthritis disease. Carrying out exercises and physical activities can help improve the health state of patients with knee osteoarthritis problem and can also improve the elders’ mental condition and thus decrease their pain and depression.

  2. Cross-border merger & acquisition activity and revealed comparative advantage in manufacturing industries

    NARCIS (Netherlands)

    Brakman, Steven; Garretsen, Harry; van Marrewijk, Charles; van Witteloostuijn, Arjen

    2013-01-01

    We estimate an important implication of oligopolistic international trade modeling for the predicted pattern of cross-border mergers and acquisitions (M&As). Our core argument is that cross-border M&As are, among other factors, driven by cross-country differences in comparative advantage. We find

  3. Cross-border merger & acquisition activity and revealed comparative advantage in manufacturing industries

    NARCIS (Netherlands)

    Brakman, Steven; Garretsen, Harry; van Marrewijk, Charles; van Witteloostuijn, Arjen

    2013-01-01

    We estimate an important implication of oligopolistic international trade modeling for the predicted pattern of cross-border mergers and acquisitions (M&As). Our core argument is that cross-border M&As are, among other factors, driven by cross-country differences in comparative advantage. We find st

  4. COMPARATIVE MODELLING AND LIGAND BINDING SITE PREDICTION OF A FAMILY 43 GLYCOSIDE HYDROLASE FROM Clostridium thermocellum

    Directory of Open Access Journals (Sweden)

    Shadab Ahmed

    2012-06-01

    Full Text Available The phylogenetic analysis of Clostridium thermocellum family 43 glycoside hydrolase (CtGH43 showed close evolutionary relation with carbohydrate binding family 6 proteins from C. cellulolyticum, C. papyrosolvens, C. cellulyticum, and A. cellulyticum. Comparative modeling of CtGH43 was performed based on crystal structures with PDB IDs 3C7F, 1YIF, 1YRZ, 2EXH and 1WL7. The structure having lowest MODELLER objective function was selected. The three-dimensional structure revealed typical 5-fold beta–propeller architecture. Energy minimization and validation of predicted model with VERIFY 3D indicated acceptability of the proposed atomic structure. The Ramachandran plot analysis by RAMPAGE confirmed that family 43 glycoside hydrolase (CtGH43 contains little or negligible segments of helices. It also showed that out of 301 residues, 267 (89.3% were in most favoured region, 23 (7.7% were in allowed region and 9 (3.0% were in outlier region. IUPred analysis of CtGH43 showed no disordered region. Active site analysis showed presence of two Asp and one Glu, assumed to form a catalytic triad. This study gives us information about three-dimensional structure and reaffirms the fact that it has the similar core 5-fold beta–propeller architecture and so probably has the same inverting mechanism of action with the formation of above mentioned catalytic triad for catalysis of polysaccharides.

  5. Developing a multidisciplinary model of comparative effectiveness research within a clinical and translational science award.

    Science.gov (United States)

    Marantz, Paul R; Strelnick, A Hal; Currie, Brian; Bhalla, Rohit; Blank, Arthur E; Meissner, Paul; Selwyn, Peter A; Walker, Elizabeth A; Hsu, Daphne T; Shamoon, Harry

    2011-06-01

    The Clinical and Translational Science Awards (CTSAs) were initiated to improve the conduct and impact of the National Institutes of Health's research portfolio, transforming training programs and research infrastructure at academic institutions and creating a nationwide consortium. They provide a model for translating research across disciplines and offer an efficient and powerful platform for comparative effectiveness research (CER), an effort that has long struggled but enjoys renewed hope under health care reform. CTSAs include study design and methods expertise, informatics, and regulatory support; programs in education, training, and career development in domains central to CER; and programs in community engagement.Albert Einstein College of Medicine of Yeshiva University and Montefiore Medical Center have entered a formal partnership that places their CTSA at a critical intersection for clinical and translational research. Their CTSA leaders were asked to develop a strategy for enhancing CER activities, and in 2010 they developed a model that encompasses four broadly defined "compartments" of research strength that must be coordinated for this enterprise to succeed: evaluation and health services research, biobehavioral research and prevention, efficacy studies and clinical trials, and social science and implementation research.This article provides historical context for CER, elucidates Einstein-Montefiore's CER model and strategic planning efforts, and illustrates how a CTSA can provide vision, leadership, coordination, and services to support an academic health center's collaborative efforts to develop a robust CER portfolio and thus contribute to the national effort to improve health and health care.

  6. Model-based Comparative Prediction of Transcription-Factor Binding Motifs in Anabolic Responses in Bone

    Institute of Scientific and Technical Information of China (English)

    Andy; B.; Chen; Kazunori; Hamamura; Guohua; Wang; Weirong; Xing; Subburaman; Mohan; Hiroki; Yokota; Yunlong; Liu

    2007-01-01

    Understanding the regulatory mechanism that controls the alteration of global gene expression patterns continues to be a challenging task in computational biology. We previously developed an ant algorithm, a biologically-inspired computational technique for microarray data, and predicted putative transcription-factor binding motifs (TFBMs) through mimicking interactive behaviors of natural ants. Here we extended the algorithm into a set of web-based software, Ant Modeler, and applied it to investigate the transcriptional mechanism underlying bone formation. Mechanical loading and administration of bone morphogenic proteins (BMPs) are two known treatments to strengthen bone. We addressed a question: Is there any TFBM that stimulates both "anabolic responses of mechanical loading" and "BMP-mediated osteogenic signaling"? Although there is no significant overlap among genes in the two responses, a comparative model-based analysis suggests that the two independent osteogenic processes employ common TFBMs, such as a stress responsive element and a motif for peroxisome proliferator-activated recep- tor (PPAR). The post-modeling in vitro analysis using mouse osteoblast cells sup- ported involvements of the predicted TFBMs such as PPAR, Ikaros 3, and LMO2 in response to mechanical loading. Taken together, the results would be useful to derive a set of testable hypotheses and examine the role of specific regulators in complex transcriptional control of bone formation.

  7. An Active Model for Facial Feature Tracking

    Directory of Open Access Journals (Sweden)

    Jörgen Ahlberg

    2002-06-01

    Full Text Available We present a system for finding and tracking a face and extract global and local animation parameters from a video sequence. The system uses an initial colour processing step for finding a rough estimate of the position, size, and inplane rotation of the face, followed by a refinement step drived by an active model. The latter step refines the pre­vious estimate, and also extracts local animation parame­ters. The system is able to track the face and some facial features in near real-time, and can compress the result to a bitstream compliant to MPEG-4 face and body animation.

  8. Applying fuzzy logic to comparative distribution modelling: a case study with two sympatric amphibians.

    Science.gov (United States)

    Barbosa, A Márcia; Real, Raimundo

    2012-01-01

    We modelled the distributions of two toads (Bufo bufo and Epidalea calamita) in the Iberian Peninsula using the favourability function, which makes predictions directly comparable for different species and allows fuzzy logic operations to relate different models. The fuzzy intersection between individual models, representing favourability for the presence of both species simultaneously, was compared with another favourability model built on the presences shared by both species. The fuzzy union between individual models, representing favourability for the presence of any of the two species, was compared with another favourability model based on the presences of either or both of them. The fuzzy intersections between favourability for each species and the complementary of favourability for the other (corresponding to the logical operation "A and not B") were compared with models of exclusive presence of one species versus the exclusive presence of the other. The results of modelling combined species data were highly similar to those of fuzzy logic operations between individual models, proving fuzzy logic and the favourability function valuable for comparative distribution modelling. We highlight several advantages of fuzzy logic over other forms of combining distribution models, including the possibility to combine multiple species models for management and conservation planning.

  9. Comparative Studies of Clustering Techniques for Real-Time Dynamic Model Reduction

    CERN Document Server

    Hogan, Emilie; Halappanavar, Mahantesh; Huang, Zhenyu; Lin, Guang; Lu, Shuai; Wang, Shaobu

    2015-01-01

    Dynamic model reduction in power systems is necessary for improving computational efficiency. Traditional model reduction using linearized models or offline analysis would not be adequate to capture power system dynamic behaviors, especially the new mix of intermittent generation and intelligent consumption makes the power system more dynamic and non-linear. Real-time dynamic model reduction emerges as an important need. This paper explores the use of clustering techniques to analyze real-time phasor measurements to determine generator groups and representative generators for dynamic model reduction. Two clustering techniques -- graph clustering and evolutionary clustering -- are studied in this paper. Various implementations of these techniques are compared and also compared with a previously developed Singular Value Decomposition (SVD)-based dynamic model reduction approach. Various methods exhibit different levels of accuracy when comparing the reduced model simulation against the original model. But some ...

  10. Comparative study of model prediction of diffuse nutrient losses in response to changes in agricultural practices

    NARCIS (Netherlands)

    Vagstad, N.; French, H.K.; Andersen, H.E.; Groenendijk, P.; Siderius, C.

    2009-01-01

    This article presents a comparative study of modelled changes in nutrient losses from two European catchments caused by modifications in agricultural practices. The purpose was not to compare the actual models used, but rather to assess the uncertainties a manager may be faced with after receiving d

  11. Comparing responses to horticultural-based and traditional activities in dementia care programs.

    Science.gov (United States)

    Jarrott, Shannon E; Gigliotti, Christina M

    2010-12-01

    Engaging persons with dementia in meaningful activities supports well-being; however, care staff are challenged to implement age- and ability-appropriate activities in a group setting. We compared a randomly assigned treatment group, who received horticultural therapy-based (HT-based) programming to a comparison group, who engaged in traditional activities (TA) programming, on engagement and affect. Horticultural therapy-based programming was implemented twice weekly at 4 treatment sites for 6 weeks, while regular TA were observed at comparison sites. Results revealed no differences between groups on affective domains. Levels of adaptive behavior differed between the groups, with the treatment group demonstrating higher levels of active, passive, and other engagement and the comparison group demonstrating higher levels of self-engagement. Our results highlight the value of HT-based programs and the importance of simultaneously capturing participants' affective and behavioral responses. Theoretical and practical considerations about the facilitation of and context in which the programming occurs are discussed.

  12. Antimicrobial Activity of Ceftriaxone Compared with Cefotaxime in the Presence of Serum Albumin

    Directory of Open Access Journals (Sweden)

    Swapan K Nath

    1995-01-01

    Full Text Available The effect of serum albumin on the antimicrobial activity of ceftriaxone, cefotaxime, and a 1:1 ratio of cefotaxime and its desacetyl metabolite against nonpseudomonal Gram-negative bacilli was determined. Antimicrobial activity of drugs was evaluated by measuring minimum inhibitory (mic and bactericidal (mbc concentrations in broth with and without human serum albumin. The analysis of logarithmically transformed mean mics and mbcs showed that there was a highly significant interaction between drug and serum albumin (P<0.0001. The inhibitory and bactericidal activities were greatest for cefotaxime followed by cefotaxime/desacetylcefotaxime and ceftriaxone (P<0.01. Time-kill kinetics demonstrated that ceftriaxone was less bactericidal than cefotaxime in broth with albumin. On the basis of these results it was concluded that the in vitro antimicrobial activity of ceftriaxone compared with that of cefotaxime was significantly diminished in the presence of serum albumin.

  13. A Comparative Study of the Jerome Model and the Horace Model

    Institute of Scientific and Technical Information of China (English)

    李子英

    2014-01-01

    For many years, the two important translation styles, the Jerome model and the Horace model, are widely studied. Consisting of four parts, this paper will focus on making a comparison between the two translation models.

  14. Comparative toxicity and efficacy of engineered anthrax lethal toxin variants with broad anti-tumor activities

    Energy Technology Data Exchange (ETDEWEB)

    Peters, Diane E. [Proteases and Tissue Remodeling Section, Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD (United States); Program of Pharmacology and Experimental Therapeutics, Tufts University School of Medicine, Boston, MA (United States); Hoover, Benjamin [Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD (United States); Cloud, Loretta Grey [Proteases and Tissue Remodeling Section, Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD (United States); Liu, Shihui [Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD (United States); Molinolo, Alfredo A. [Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD (United States); Leppla, Stephen H. [Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD (United States); Bugge, Thomas H., E-mail: thomas.bugge@nih.go [Proteases and Tissue Remodeling Section, Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD (United States)

    2014-09-01

    We have previously designed and characterized versions of anthrax lethal toxin that are selectively cytotoxic in the tumor microenvironment and which display broad and potent anti-tumor activities in vivo. Here, we have performed the first direct comparison of the safety and efficacy of three engineered anthrax lethal toxin variants requiring activation by either matrix-metalloproteinases (MMPs), urokinase plasminogen activator (uPA) or co-localized MMP/uPA activities. C57BL/6J mice were challenged with six doses of engineered toxins via intraperitoneal (I.P.) or intravenous (I.V.) dose routes to determine the maximum tolerated dose for six administrations (MTD6) and dose-limiting toxicities. Efficacy was evaluated using the B16-BL6 syngraft model of melanoma; mice bearing established tumors were treated with six I.P. doses of toxin and tumor measurements and immunohistochemistry, paired with terminal blood work, were used to elaborate upon the anti-tumor mechanism and relative efficacy of each variant. We found that MMP-, uPA- and dual MMP/uPA-activated anthrax lethal toxins exhibited the same dose-limiting toxicity; dose-dependent GI toxicity. In terms of efficacy, all three toxins significantly reduced primary B16-BL6 tumor burden, ranging from 32% to 87% reduction, and they also delayed disease progression as evidenced by dose-dependent normalization of blood work values. While target organ toxicity and effective doses were similar amongst the variants, the dual MMP/uPA-activated anthrax lethal toxin exhibited the highest I.P. MTD6 and was 1.5–3-fold better tolerated than the single MMP- and uPA-activated toxins. Overall, we demonstrate that this dual MMP/uPA-activated anthrax lethal toxin can be administered safely and is highly effective in a preclinical model of melanoma. This modified bacterial cytotoxin is thus a promising candidate for further clinical development and evaluation for use in treating human cancers. - Highlights: • Toxicity and anti

  15. Comparative modeling analyses of Cs-137 fate in the rivers impacted by Chernobyl and Fukushima accidents

    Energy Technology Data Exchange (ETDEWEB)

    Zheleznyak, M.; Kivva, S. [Institute of Environmental Radioactivity, Fukushima University (Japan)

    2014-07-01

    The consequences of two largest nuclear accidents of the last decades - at Chernobyl Nuclear Power Plant (ChNPP) (1986) and at Fukushima Daiichi NPP (FDNPP) (2011) clearly demonstrated that radioactive contamination of water bodies in vicinity of NPP and on the waterways from it, e.g., river- reservoir water after Chernobyl accident and rivers and coastal marine waters after Fukushima accident, in the both cases have been one of the main sources of the public concerns on the accident consequences. The higher weight of water contamination in public perception of the accidents consequences in comparison with the real fraction of doses via aquatic pathways in comparison with other dose components is a specificity of public perception of environmental contamination. This psychological phenomenon that was confirmed after these accidents provides supplementary arguments that the reliable simulation and prediction of the radionuclide dynamics in water and sediments is important part of the post-accidental radioecological research. The purpose of the research is to use the experience of the modeling activities f conducted for the past more than 25 years within the Chernobyl affected Pripyat River and Dnieper River watershed as also data of the new monitoring studies in Japan of Abukuma River (largest in the region - the watershed area is 5400 km{sup 2}), Kuchibuto River, Uta River, Niita River, Natsui River, Same River, as also of the studies on the specific of the 'water-sediment' {sup 137}Cs exchanges in this area to refine the 1-D model RIVTOX and 2-D model COASTOX for the increasing of the predictive power of the modeling technologies. The results of the modeling studies are applied for more accurate prediction of water/sediment radionuclide contamination of rivers and reservoirs in the Fukushima Prefecture and for the comparative analyses of the efficiency of the of the post -accidental measures to diminish the contamination of the water bodies. Document

  16. Active microrheology of a model of the nuclear micromechanical environment

    Science.gov (United States)

    Byrd, Henry; Kilfoil, Maria

    2014-03-01

    In order to successfully complete the final stages of chromosome segregation, eukaryotic cells require the motor enzyme topoisomerase II, which can resolve topological constraints between entangled strands of duplex DNA. We created an in vitro model of a close approximation of the nuclear micromechanical environment in terms of DNA mass and entanglement density, and investigated the influence of this motor enzyme on the DNA mechanics. Topoisomerase II is a non-processive ATPase which we found significantly increases the motions of embedded microspheres in the DNA network. Because of this activity, we study the mechanical properties of our model system by active microrheology by optical trapping. We test the limits of fluctuation dissipation theorem (FDT) under this type of activity by comparing the active microrheology to passive measurements, where thermal motion alone drives the beads. We can relate any departure from FDT to the timescale of topoisomerase II activity in the DNA network. These experiments provide insight into the physical necessity of this motor enzyme in the cell.

  17. COMPARISON BETWEEN DIFFERENT MODELS FOR RHEOLOGICAL CHARACTERIZATION OF ACTIVATED SLUDGE

    Directory of Open Access Journals (Sweden)

    A. H. Khalili Garakani

    2011-09-01

    Full Text Available Activated sludge flow rheology is a very complicated phenomenon. Studies related to activated sludge tend to classify sludge as non-Newtonian fluid. Until now, several theories have been built to describe the complex behavior of activated sludge with varying degrees of success. In this article, seven different models for viscosity of non-Newtonian fluids (i.e., Power law, Bingham plastic, Herschel-Bulkley, Casson, Sisko, Carreau and Cross were considered to evaluate their predictive capability of apparent viscosity of activated sludge. Results showed that although evaluating the constants in the four-parameter models is difficult, they provide the best prediction of viscosity in the whole range of shear rates for activated sludge. For easier prediction of viscosity at different mixed liquor suspended solids (2.74-31g/L, temperature (15-25°C and shear rate (1-1000/s, simple correlations were proposed. Comparing the results with the experimental data revealed that the proposed correlations are in good agreement with real apparent viscosities.

  18. Business model in research-development activity

    Directory of Open Access Journals (Sweden)

    Koszałka Jerzy

    2016-09-01

    Full Text Available The partners and allies of business practice in the processes of modernization of the economy are scientific-research institutions, such as scientific institutes, research-development units and universities. A market on which companies can look for the solutions they need and scientific-research institutions can look for inspiration, partners and capital is being formed. The market provides conditions for operation, development and implementation of developed solutions. Taking into consideration the complexity of market, technical, legal, financial, or intellectual property protection issues, research-development units are more and more frequently unable to function efficiently without a clear and unequivocal definition of goals, methods and conditions of activity. Their market offer has to take into consideration not just scientific-research, or methodological aspects. Taking into consideration continuously growing demands of the clients and pressure of the competition, scientific-research institutions have to pay attention also to market, information, personnel, or financial aspects typical of strictly commercial ventures. What may support a comprehensive preparation and implementation of scientific-research activities under market conditions are tools successfully used in trade and economy, such as business models. These issues are the basis of deliberations contained in this work.

  19. Modeling and experimental vibration analysis of nanomechanical cantilever active probes

    Science.gov (United States)

    Salehi-Khojin, Amin; Bashash, Saeid; Jalili, Nader

    2008-08-01

    Nanomechanical cantilever (NMC) active probes have recently received increased attention in a variety of nanoscale sensing and measurement applications. Current modeling practices call for a uniform cantilever beam without considering the intentional jump discontinuities associated with the piezoelectric layer attachment and the NMC cross-sectional step. This paper presents a comprehensive modeling framework for modal characterization and dynamic response analysis of NMC active probes with geometrical discontinuities. The entire length of the NMC is divided into three segments of uniform beams followed by applying appropriate continuity conditions. The characteristics matrix equation is then used to solve for system natural frequencies and mode shapes. Using an equivalent electromechanical moment of a piezoelectric layer, forced motion analysis of the system is carried out. An experimental setup consisting of a commercial NMC active probe from Veeco and a state-of-the-art microsystem analyzer, the MSA-400 from Polytec, is developed to verify the theoretical developments proposed here. Using a parameter estimation technique based on minimizing the modeling error, optimal values of system parameters are identified. Mode shapes and the modal frequency response of the system for the first three modes determined from the proposed model are compared with those obtained from the experiment and commonly used theory for uniform beams. Results indicate that the uniform beam model fails to accurately predict the actual system response, especially in multiple-mode operation, while the proposed discontinuous beam model demonstrates good agreement with the experimental data. Such detailed and accurate modeling framework can lead to significant enhancement in the sensitivity of piezoelectric-based NMC sensors for use in variety of sensing and imaging applications.

  20. Comparative Studies on Polyphenolic Composition, Antioxidant and Antimicrobial Activities of Schisandra chinensis Leaves and Fruits

    Directory of Open Access Journals (Sweden)

    Andrei Mocan

    2014-09-01

    Full Text Available The aim of this paper was to evaluate the antioxidant and antimicrobial activities and the polyphenolic content of Schisandra chinensis (Turcz. Baill. leaves and fruits. The leaves are an important source of flavonoids (35.10 ± 1.23 mg RE/g plant material. Qualitative and quantitative analyses of the polyphenolic compounds were achieved using a HPLC-UV-MS method. The main flavonoid from the leaves was isoquercitrin (2486.18 ± 5.72 μg/g plant material, followed by quercitrin (1645.14 ± 2.12 μg/g plant material. Regarding the fruit composition, the dominant compound there was rutin (13.02 ± 0.21 μg/g plant material, but comparing with the leaves, fruits can be considered a poor source of phenolic compounds. The antioxidant activity was evaluated by DPPH, TEAC, hemoglobin ascorbate peroxidase activity inhibition (HAPX, inhibition of lipid peroxidation catalyzed by cytochrome c and EPR spectroscopic assays, revealing a better antioxidant activity for the S. chinensis leaves extract. In the antimicrobial assay, S. chinensis leaves extract showed efficient activities against the targeted bacteria, being more active than the fruits extract. The results suggest the leaves of S. chinensis as a valuable source of antioxidant compounds with significant antioxidant activity.

  1. Comparative studies on polyphenolic composition, antioxidant and antimicrobial activities of Schisandra chinensis leaves and fruits.

    Science.gov (United States)

    Mocan, Andrei; Crișan, Gianina; Vlase, Laurian; Crișan, Ovidiu; Vodnar, Dan Cristian; Raita, Oana; Gheldiu, Ana-Maria; Toiu, Anca; Oprean, Radu; Tilea, Ioan

    2014-01-01

    The aim of this paper was to evaluate the antioxidant and antimicrobial activities and the polyphenolic content of Schisandra chinensis (Turcz.) Baill. leaves and fruits. The leaves are an important source of flavonoids (35.10 ± 1.23 mg RE/g plant material). Qualitative and quantitative analyses of the polyphenolic compounds were achieved using a HPLC-UV-MS method. The main flavonoid from the leaves was isoquercitrin (2486.18 ± 5.72 μg/g plant material), followed by quercitrin (1645.14 ± 2.12 μg/g plant material). Regarding the fruit composition, the dominant compound there was rutin (13.02 ± 0.21 μg/g plant material), but comparing with the leaves, fruits can be considered a poor source of phenolic compounds. The antioxidant activity was evaluated by DPPH, TEAC, hemoglobin ascorbate peroxidase activity inhibition (HAPX), inhibition of lipid peroxidation catalyzed by cytochrome c and EPR spectroscopic assays, revealing a better antioxidant activity for the S. chinensis leaves extract. In the antimicrobial assay, S. chinensis leaves extract showed efficient activities against the targeted bacteria, being more active than the fruits extract. The results suggest the leaves of S. chinensis as a valuable source of antioxidant compounds with significant antioxidant activity.

  2. Enhanced adsorption of humic acids on ordered mesoporous carbon compared with microporous activated carbon.

    Science.gov (United States)

    Liu, Fengling; Xu, Zhaoyi; Wan, Haiqin; Wan, Yuqiu; Zheng, Shourong; Zhu, Dongqiang

    2011-04-01

    Humic acids are ubiquitous in surface and underground waters and may pose potential risk to human health when present in drinking water sources. In this study, ordered mesoporous carbon was synthesized by means of a hard template method and further characterized by X-ray diffraction, N2 adsorption, transition electron microscopy, elemental analysis, and zeta-potential measurement. Batch experiments were conducted to evaluate adsorption of two humic acids from coal and soil, respectively, on the synthesized carbon. For comparison, a commercial microporous activated carbon and nonporous graphite were included as additional adsorbents; moreover, phenol was adopted as a small probe adsorbate. Pore size distribution characterization showed that the synthesized carbon had ordered mesoporous structure, whereas the activated carbon was composed mainly of micropores with a much broader pore size distribution. Accordingly, adsorption of the two humic acids was substantially lower on the activated carbon than on the synthesized carbon, because of the size-exclusion effect. In contrast, the synthesized carbon and activated carbon showed comparable adsorption for phenol when the size-exclusion effect was not in operation. Additionally, we verified by size-exclusion chromatography studies that the synthesized carbon exhibited greater adsorption for the large humic acid fraction than the activated carbon. The pH dependence of adsorption on the three carbonaceous adsorbents was also compared between the two test humic acids. The findings highlight the potential of using ordered mesoporous carbon as a superior adsorbent for the removal of humic acids.

  3. Comparing different Ultraviolet Imaging Spectrograph (UVIS) occultation observations using modeling of water vapor jets

    Science.gov (United States)

    Portyankina, Ganna; Esposito, Larry W.; Hansen, Candice; Aye, Klaus-Michael

    2016-10-01

    Motivation: On March 11, 2016 the Cassini UVIS observed its 6th star occultation by Enceladus' plume. This observation was aimed to determine variability in the total gas flux from the Enceladus' southern polar region. The analysis of the received data suggests that the total gas flux is moderately increased comparing to the average gas flux observed by UVIS from 2005 to 2011 [1]. However, UVIS detected variability in individual jets. In particular, Baghdad 1 is more collimated in 2016 than in 2005, meaning its gas escapes at higher velocity.Model and fits: We use 3D DSMC model for water vapor jets to compare different UVIS occultation observations from 2005 to 2016. The model traces test articles from jets' sources [2] into space and results in coordinates and velocities for a set of test particles. We convert particle positions into the particle number density and integrate along UVIS line of sight (LoS) for each time step of the UVIS observation using precise observational geometry derived from SPICE [3]. We integrate all jets that are crossed by the LoS and perform constrained least-squares fit of resulting modeled opacities to the observed data to solved for relative strengths of jets. The geometry of each occultation is specific, for example, during solar occultation in 2010 UVIS LoS was almost parallel to tiger stripes, which made it possible to distinguish jets venting from different tiger stripes. In 2011 Eps Orionis occultation LoS was perpendicular to tiger stripes and thus many of the jets were geometrically overlapping. Solar occultation provided us with the largest inventory of active jets - our model fit detects at least 43 non-zero jet contributions. Stellar occultations generally have lower temporal resolution and observe only a sub-set of these jets: 2011 Eps Orionis needs minimum 25 non-zero jets to fit UVIS data. We will discuss different occultations and models fits, including the most recent Epsilon Orionis occultation of 2016.[1] Hansen et al

  4. [In vitro activity of roxithromycin compared to 5 other macrolides against staphylococci].

    Science.gov (United States)

    Brun, Y; Coulet, M; Forey, F; Fleurette, J

    1988-06-01

    This study aimed to compare the bacteriostatic activity of roxithromycin (RU) to those of erythromycin (ERY), troleandomycin (TAO), spiramycin (SPI), josamycin (JOS) and midekamycin (MID) against staphylococci strains. 239 strains of hospital origin were analysed: S. aureus (139), coagulase negative staphylococci (CNS) (100). The MIC were determined by the agar dilution method. The modal MIC, the MIC 50 and 90 observed for the both groups of strains are given according to species and antibiotics. This study gives the opportunity to classify the 6 antibiotics in a decreasing order considering their antistaphylococcal activity: RU = ERY, TAO = SPI, JOS = MID. No difference was noticeable between S. aureus and CNS strains.

  5. Continuous Molecular Fields Approach Applied to Structure-Activity Modeling

    CERN Document Server

    Baskin, Igor I

    2013-01-01

    The Method of Continuous Molecular Fields is a universal approach to predict various properties of chemical compounds, in which molecules are represented by means of continuous fields (such as electrostatic, steric, electron density functions, etc). The essence of the proposed approach consists in performing statistical analysis of functional molecular data by means of joint application of kernel machine learning methods and special kernels which compare molecules by computing overlap integrals of their molecular fields. This approach is an alternative to traditional methods of building 3D structure-activity and structure-property models based on the use of fixed sets of molecular descriptors. The methodology of the approach is described in this chapter, followed by its application to building regression 3D-QSAR models and conducting virtual screening based on one-class classification models. The main directions of the further development of this approach are outlined at the end of the chapter.

  6. Material Models Used to Predict Spring-in of Composite Elements: a Comparative Study

    Science.gov (United States)

    Galińska, Anna

    2017-02-01

    There have been several approaches used in the modelling of the process-induced deformations of composite parts developed so far. The most universal and most frequently used approach is the FEM modelling. In the scope of the FEM modelling several material models have been used to model the composite behaviour. In the present work two of the most popular material models: elastic and CHILE (cure hardening instantaneous linear elastic) are used to model the spring-in deformations of composite specimens and a structure fragment. The elastic model is more effective, whereas the CHILE model is considered more accurate. The results of the models are compared with each other and with the measured deformations of the real composite parts. Such a comparison shows that both models allow to predict the deformations reasonably well and that there is little difference between their results. This leads to a conclusion that the use of the simpler elastic model is a valid engineering practice.

  7. Active contour model based on force field analysis

    Institute of Scientific and Technical Information of China (English)

    HOU Zhi-qiang; HAN Chong-zhao

    2006-01-01

    The traditional snake initial contour should be close to the true boundary of an object of interest in an image;otherwise,an incorrect result will be obtained.Next,active contours have difficulties progressing into boundary concavities.Moreover,the traditional snake as well as almost all of its improved methods can be easily obtained from the local minimum because snake models are nonconvex.An active contour model based on force field analysis (FFA),namely,FFA snake model,is presented in this paper.Based on analyzing force distribution rules of the distance potential force field,a standard is introduced here to distinguish the false one from contour points.The result is not considered as the final solution when the snake energy is minimal.Furthermore,estimation and calculation should be made according to the established standard;only then can the result be considered final.Thus,the snake is prevented from running into the local minimum.The simulation results show that the FFA snake model has a large capture range and can move a snake into the boundary concavities,and that it is able to obtain the object of interest's contour precisely.Compared with the gradient vector flow snake,this new model has a low computational cost.

  8. Comparing modelled and remotely sensed leaf area dynamics in an Aleppo pine semiarid forest

    Science.gov (United States)

    Pasquato, Marta; Medici, Chiara; Friend, Andrew D.; Francés, Félix

    2013-04-01

    Much of the Earth's terrestrial surface is subject to arid climatic water stress. In these regions, plant ecosystems are controlled by water availability, inducing a tight interconnection between the hydrological cycle and the vegetation dynamics. For this reason, and to fully reproduce water-controlled ecosystems' behaviour, it is essential to jointly model vegetation and the hydrological cycle. In this work, the performance of a parsimonious dynamic vegetation model, suitable for the inclusion in a conceptual ecohydrological model, is tested in a semi-arid Aleppo Pine forest area in the south-east of Spain. The model simulates gross primary production (GPP) as a function of absorbed photosynthetically active radiation (APAR) and the light use efficiency (LUE). Net primary production (NPP) is then calculated taking into account maintenance respiration. The modelling is focused particularly on simulating foliar biomass, which is obtained from NPP through an allocation equation based on the maximum LAI sustainable by the system, and considering turnover. An analysis of the information offered by MODIS EVI, NDVI, and LAI products was performed in order to investigate vegetation dynamics in the study site and to select the best indices to be used to evaluate the ecohydrological model's performance. EVI is reported in literature (Huete et al., 2002) to be sensitive to canopy structure, particularly to leaf area index (LAI). In accordance with the phenological cycle timing described for the Aleppo pine in similar climates (Muñoz et al., 2003), the EVI showed maximum values in spring and minimum values in winter. Similar results were found applying the aforementioned vegetation model to the study area. Contrasting simulated LAI with the EVI series, a correlation coefficient r = 0.57 was found. Concerning NDVI, its own definition links this index to the "greenness" of the target, so that it appears highly linked to chlorophyll content and vegetation condition, but only

  9. The influence comparing of activated biochar and conventional biochar on the soil biological properties

    Science.gov (United States)

    Dvořáčková, Helena; Mykajlo, Irina; Záhora, Jaroslav

    2016-04-01

    In our experiment we have used biochar. This material is the product of the pyrolysis that has shown a positive effect on numerous physical and chemical soil properties. However, its influence on the biological component of the soil is very variable. A number of toxic substances that inhibit the soil productivity may be produced during pyrolysis process. The experiment dealt with the hypothesis concerning biochar toxicity reduction by simulating natural processes in the soil. Biochar has been exposed to aeration in the aquatic environment, enriched with nutrients and a source of native soil microflora. It has been created 6 variants in total, each with four replications. The soils samples have been placed in a phytotron for 90 days. Variants consisted of the soil with fertilizers adding (compost, biochar, activated biochar) and have been prepared as well as variants containing compost and biochar and activated biochar optionally. The highest aboveground biomass production has been estimated in variants containing compost, while the lowest production - in the variants containing conventional biochar. During production comparing of the variants with the conventional biochar, activated biochar and control samples it has been evident that activated biochar promotes plant growth, and in contradiction conventional biochar inhibits it. We will approach to the same conclusions when comparing variants with a combination of conventional biochar + compost and activated biochar + compost. Mineral nitrogen leaching has been another investigated parameter. The highest leaching has occurred in the control variant, while the lowest - in the variant with activated biochar (the leaching of nitrate nitrogen has been negligeable). Our results suggest that activated biochar has the potential; however, it is necessary to carry out similar experiments in the field conditions.

  10. Modelling and Experimental Investigation of an Active Damper

    Directory of Open Access Journals (Sweden)

    Rafael Luís Teixeira

    2006-01-01

    Full Text Available This paper presents a validation methodology of the dynamic behavior of an active viscous damper. The damper has two flexible metallic bellows connected to a rigid reservoir filled with fluid. When one of the bellows is connected to a vibrating structure a periodic flow passes through a variable internal orifice and the damping effect is produced. The size of the orifice is adjusted by a controlled linear piezoelectric actuator that positions the conical core into a conical cavity. The device finite element structural model consists of the valve body and its conical core that are assumed rigid and the flexible bellows are represented by two pistons with elastic suspensions. The flow developed inside the damper is modeled considering the fluid-structure interation, using the Lagrangean-Eulerian formulation. To validate the proposed model a prototype was constructed and experimental tests and numerical simulations are accomplished in the time domain, applying harmonic excitations. The results are compared using curves that relate the damping coefficient with the orifice size and with the input velocity applied at the bellows face. However, for the proper control design and system operation, the direct use of the finite element model becomes unviable due to its high computational time. Then, a reduced second order discrete dynamic model for the damper was developed. The model parameters are identified by analysis in the frequency domain, using impulsive excitation force, for constant and variable orifice sizes. At low excitation frequencies, the damper prototype behaves like a single degree of freedom system which damping factor changes with the orifice size A fuzzy controller was designed and it generates the orifice reference size associated to the desired damping factor. The active system presented better performance when compared to the passive one.

  11. Functional properties of soybean nodulin 26 from a comparative three-dimensional model.

    Science.gov (United States)

    Biswas, Sampa

    2004-01-30

    A model of the nodulin 26 channel protein has been constructed based on comparative modeling and molecular dynamics simulations. Structural features of the protein indicate a selectivity filter that differs from those of the known structures of Escherichia coli glycerol facilitator and mammalian aquaporin 1. The model structure also reveals important roles of Ser207 and Phe96 in ligand binding and transport.

  12. Comparative Analysis of Smart Meters Deployment Business Models on the Example of the Russian Federation Markets

    Science.gov (United States)

    Daminov, Ildar; Tarasova, Ekaterina; Andreeva, Tatyana; Avazov, Artur

    2016-02-01

    This paper presents the comparison of smart meter deployment business models to determine the most suitable option providing smart meters deployment. Authors consider 3 main business model of companies: distribution grid company, energy supplier (energosbyt) and metering company. The goal of the article is to compare the business models of power companies from massive smart metering roll out in power system of Russian Federation.

  13. Modeling and vibration control of an active membrane mirror

    Science.gov (United States)

    Ruggiero, Eric J.; Inman, Daniel J.

    2009-09-01

    The future of space satellite technology lies in ultra-large mirrors and radar apertures for significant improvements in imaging and communication bandwidths. The availability of optical-quality membranes drives a parallel effort for structural models that can capture the dominant dynamics of large, ultra-flexible satellite payloads. Unfortunately, the inherent flexibility of membrane mirrors wreaks havoc with the payload's on-orbit stability and maneuverability. One possible means of controlling these undesirable dynamics is by embedding active piezoelectric ceramics near the boundary of the membrane mirror. In doing so, active feedback control can be used to eliminate detrimental vibration, perform static shape control, and evaluate the health of the structure. The overall motivation of the present work is to design a control system using distributed bimorph actuators to eliminate any detrimental vibration of the membrane mirror. As a basis for this study, a piezoceramic wafer was attached in a bimorph configuration near the boundary of a tensioned rectangular membrane sample. A finite element model of the system was developed to capture the relevant system dynamics from 0 to 300 Hz. The finite element model was compared against experimental results, and fair agreement found. Using the validated finite element models, structural control using linear quadratic regulator control techniques was then used to numerically demonstrate effective vibration control. Typical results show that less than 12 V of actuation voltage is required to eliminate detrimental vibration of the membrane samples in less than 15 ms. The functional gains of the active system are also derived and presented. These spatially descriptive control terms dictate favorable regions within the membrane domain for placing sensors and can be used as a design guideline for structural control applications. The results of the present work demonstrate that thin plate theory is an appropriate modeling

  14. Modeling and simulation of fish swimming with active muscles.

    Science.gov (United States)

    Curatolo, Michele; Teresi, Luciano

    2016-11-21

    Our goal is to reproduce the key features of carangiform swimming by modeling muscle functioning using the notion of active distortions, thus emphasizing the kinematical role of muscle, the generation of movement, rather than the dynamical one, the production of force. This approach, already proposed to model the action of muscles in different contexts, is here tested again for the problem of developing an effective and reliable framework to model and simulate swimming. A proper undulatory movement of a fish-like body is reproduced by defining a pattern of distortions, tuned in both space and time, meant to model the muscles activation which produce the flexural motion of body fish; eventually, interactions with the surrounding water yields the desired thrust. Carangiform swimmers have a relatively inflexible anterior body section and a generally flat, flexible posterior section. Because of this configuration, undulations sent rearward along the body attain a significant amplitude only in the posterior section. We compare the performances of different swimming gaits, and we are able to find some important relations between key parameters such as frequencies, wavelength, tail amplitude, and the achieved swim velocity, or the generated thrust, which summarize the swimming performance. In particular, an interesting relation is found between the Strouhal number and the wavelength of muscles activation. We highlight the muscle function during fish locomotion describing the activation of muscles and the relation between the force production and the shortening-lengthening cycle of muscle. We found a great accordance between results and empirical relations, giving an implicit validation of our models. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Comparative Antianaerobic Activities of Doripenem Determined by MIC and Time-Kill Analysis▿

    Science.gov (United States)

    Credito, Kim L.; Ednie, Lois M.; Appelbaum, Peter C.

    2008-01-01

    Against 447 anaerobe strains, the investigational carbapenem doripenem had an MIC50 of 0.125 μg/ml and an MIC90 of 1 μg/ml. Results were similar to those for imipenem, meropenem, and ertapenem. Time-kill studies showed that doripenem had very good bactericidal activity compared to other carbapenems, with 99.9% killing of 11 strains at 2× MIC after 48 h. PMID:17938185

  16. Comparative antianaerobic activities of doripenem determined by MIC and time-kill analysis.

    Science.gov (United States)

    Credito, Kim L; Ednie, Lois M; Appelbaum, Peter C

    2008-01-01

    Against 447 anaerobe strains, the investigational carbapenem doripenem had an MIC 50 of 0.125 microg/ml and an MIC 90 of 1 microg/ml. Results were similar to those for imipenem, meropenem, and ertapenem. Time-kill studies showed that doripenem had very good bactericidal activity compared to other carbapenems, with 99.9% killing of 11 strains at 2x MIC after 48 h.

  17. Comparative estrogenic activity of wine extracts and organochlorine pesticide residues in food.

    OpenAIRE

    Gaido, K.; Dohme, L; Wang, F.; Chen, I; Blankvoort, B; Ramamoorthy, K; Safe, S.

    1998-01-01

    The human diet contains industrial-derived, endocrine-active chemicals and higher levels of naturally occurring compounds that modulate multiple endocrine pathways. Hazard and risk assessment of these mixtures is complicated by noadditive interactions between different endocrine-mediated responses. This study focused on estrogenic chemicals in the diet and compared the relative potencies or estrogen equivalents (EQs) of the daily consumption of xenoestrogenic organochlorine pesticides in food...

  18. Comparative activation states of tumor-associated and peritoneal macrophages from mice bearing an induced fibrosarcoma.

    Science.gov (United States)

    Valdez, J C; de Alderete, N; Meson, O E; Sirena, A; Perdigon, G

    1990-11-01

    Balb/c mice bearing a methylcholanthrene-induced fibrosarcoma were used to compare the activation levels of tumor-associated and peritoneal macrophages. Two stages of tumor growth were examined, namely "small" and "large" tumors, with average diameters of 10 and 30 mm, respectively. The activation state, determined by measurement of both phagocytic index and beta-glucuronidase content, was found to be markedly higher in tumor-associated macrophages than in their peritoneal counterparts and it was, in addition, independent of tumor progression. The percentage of tumor-associated macrophages, which were detected on the basis of Fc receptor expression, remained constant in the growing neoplasm, at approximately 23% of total cell population. None of these parameters were affected by inoculation with an immunopotentiating dose of heat-killed Candida albicans which, on the other hand, seemed not to alter the course of the tumor. These data suggest that within the tumor microenvironment macrophages would somehow be maintained at a constant proportion and at a highly activated state, while outside the tumor they would be at a lower activation level. Our results also suggest that TAM would not possess antitumor activity in vivo, although we have found this activity in vitro.

  19. Anti-granuloma activity of Coriandrum sativum in experimental models

    Directory of Open Access Journals (Sweden)

    Vinod Nair

    2013-01-01

    Full Text Available Background: Coriandrum sativum has been used in the traditional systems of medicine for management of arthritis and other inflammatory disorders. Objectives: In this study, we have evaluated the anti-inflammatory and anti-granuloma activities of Coriandrum sativum hydroalcoholic extract (CSHE in experimental models. Materials and Methods: The anti-inflammatory activity of CSHE was evaluated using carrageenan-induced paw edema model and the anti-granuloma activity of CSHE was evaluated using the subcutaneous cotton pellet implantation-induced granuloma formation and stimulation of peritoneal macrophages with complete Freund′s adjuvant. Serum tumor necrosis factor-α (TNF-α, IL-6, IL-1 β levels, and peritoneal macrophage expression of TNF-R1 were evaluated as markers of global inflammation. Results: CSHE at the highest dose tested (32 mg/kg produced a significant reduction (P < 0.05 in paw edema after carrageenan administration. CSHE treatment also reduced dry granuloma weight in all treated animals. Serum IL-6 and IL-1 β levels were significantly ( P < 0.05 lower in the CSHE (32 mg/kg-treated group as compared to control. Although there was an increase in serum TNF-α level in the CSHE-treated group as compared to control, TNF-R1 expression on peritoneal macrophages was found to be reduced. Conclusion: Thus, the result of this study demonstrates the anti-inflammatory and anti-granuloma activities of CSHE in experimental models, and validates its traditional use for the management of arthritis and other inflammatory disorders.

  20. Comparative evaluation of the use of artificial neural networks for modelling the epidemiology of schistosomiasis mansoni.

    Science.gov (United States)

    Hammad, T A; Abdel-Wahab, M F; DeClaris, N; El-Sahly, A; El-Kady, N; Strickland, G T

    1996-01-01

    There has been a marked increase in the application of approaches based on artificial intelligence (AI) in the field of computer science and medical diagnosis, but AI is still relatively unused in epidemiological settings. In this study we report results of the application of neural networks (NN; a special category of AI) to schistosomiasis. It was possible to design an NN structure which can process and fit epidemiological data collected from 251 schoolchildren in Egypt using the first year's data to predict second and third years' infection rates. Data collected over 3 years included age, gender, exposure to canal water and agricultural activities, medical history and examination, and stool and urine parasitology. Schistosoma mansoni infection rates were 50%, 78% and 66% at the baseline and the 2 follow-up periods, respectively. NN modelling was based on the standard back-propagation algorithm, in which we built a suitable configuration of the network, using the first year's data, that optimized performance. It was implemented on an IBM compatible computer using commercially available software. The performance of the NN model in the first year compared favourably with logistic regression (NN sensitivity = 83% (95% confidence interval [CI] 78-88%) and positive predictive value (PPV) = 63% (95% CI 57-69%); logistic regression sensitivity = 66% (95% CI 60%-72%) and PPV = 59% (95% CI 53%-65%). The NN model generalized the criteria for predicting infection over time better than logistic regression and showed more stability over time, as it retained its sensitivity and specificity and had better false positive and negative profiles than logistic regression. The potential of NN-based models to analyse and predict wide-scale control programme data, which are inevitably based on unstable egg excretion rates and insensitive laboratory techniques, is promising but still untapped.

  1. Latitudinal characteristics of GPS derived ionospheric TEC: a comparative study with IRI 2012 model

    Directory of Open Access Journals (Sweden)

    Monti Chakraborty

    2014-10-01

    Full Text Available The present study investigates the variation of Total Electron Content (TEC using Global Positioning System (GPS satellites from four equatorial to mid-latitudes stations over a period of one year. The stations are Port Blair (11.63°N, 92.70°E, Agartala (23.75°N, 91.25°E, Lhasa (29.65°N, 91.10°E and Urumqi (43.46°N, 87.16°E. The diurnal, monthly and seasonal variations of TEC have been explored to study its latitudinal characteristics. Analysis of TEC data from these stations reveals the characteristics of latitudinal variation of Equatorial Ionospheric Anomaly (EIA. To validate the latest IRI 2012 model, the monthly and seasonal variations of GPS-TEC at all the four stations have been compared with the model for three different topside options of electron density, namely, NeQuick, IRI-01-corr and IRI-2001. TEC predictions from IRI-2001 top side electron density option using IRI 2012 model overestimates the observed TEC especially at the low latitudes. TEC from IRI- NeQuick and IRI-01-corr options shows a tendency to underestimate the observed TEC during the day time particularly in low latitude region in the high solar activity period. The agreement between the model and observed values are reasonable in mid latitude regions. However, a discrepancy between IRI 2012 derived TEC with the ground based observations at low latitude regions is found. The discrepancy appears to be higher in low-latitude regions in comparison to mid latitude regions. It is concluded that largest discrepancy in TEC occur as a result of poor estimation of the hmF2 and foF2 from the coefficients.

  2. Treatment of industrial effluents using electron beam accelerator and adsorption with activated carbon: a comparative study

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira Sampa, M.H. de E-mail: mhosampa@ipen.br; Rela, Paulo Roberto; Las Casas, Alexandre; Nunes Mori, Manoel; Lopes Duarte, Celina

    2004-10-01

    This paper presents preliminary results of a study that compares the use of electron beam processing and activated carbon adsorption to clean up a standardized organic aqueous solution and a real industrial effluent. The electron beam treatment was performed in a batch system using the IPEN's Electron Beam Accelerators from Radiation Dynamics Inc., Dynamitron 37.5 kW. The granular activated carbon removal treatment was performed using charcoal made from wood 'pinus'. If the adequate irradiation dose is delivered to the organic pollutant, it is possible to conclude for the studied compounds that the Electron Beam Process is similar to the activated carbon process in organic removal efficiency.

  3. [In vitro comparative activity of five macrolides against 190 Branhamella catarrhalis strains].

    Science.gov (United States)

    Chardon, H; Bellon, O; Bourgeois, F; Lagier, E

    1989-05-01

    We compared the in vitro activity of 5 macrolides against 190 strains of Branhamella catarrhalis; 48 strains were isolated at Centre Hospitalier, Aix-en-Provence, the 142 others were isolated during 1987, in 15 different Centres-Hospitaliers-Généraux in France. 153 strains were betalactamase producing strains; no difference in susceptibility to erythromycin was observed on betalactamase producing and non producing strains. Three active macrolides against 100% of strains were: erythromycin (MIC 50 = 0.25 mg/l - MIC 90 = 0.50 mg/l), roxithromycin (MIC 50 = 0.50 mg/l - MIC 90 = 0.50 mg/l) and josamycin (MIC 50 = 0.50 mg/l - MIC 90 = 1 mg/l); A lower activity was noted on midecamycin (mic 50 = 2 mg/l - MIC 90 = 2 mg/l) and spiramycin (MIC 50 = 4 mg/l - MIC 90 = 8 mg/l).

  4. Comparative analysis of competitive activity parameters of amateur boxers high qualification

    Directory of Open Access Journals (Sweden)

    Martsiv V.P.

    2014-11-01

    Full Text Available Purpose : analyze competitive activity of boxers of high qualifications in different time periods in the development of boxing. Material : 142 analyzed boxing matches at the Olympic Games 2012. Results : present indicators of competitive activity of boxers. Shows the comparative characteristics of the battles that took place under different formulas of competitive activity in different periods of the development of amateur boxing. It is shown that increasing the skills of athletes appear to increase the density of hits in combat. As a result of innovations in the rules of the competition, boxing match was different higher intensity combat, attacking actions began to perform at a higher speed mode. Conclusions : As a result of the transition to the new formula of fighting to increase the density of the match. Also a 3-fold increase in the number of strikes indicator, surviving on target. Increased efficiency factor strikes, which leads to the expansion of effective technical and tactical actions.

  5. Neutron-activation revisited: the depletion and depletion-activation models.

    Science.gov (United States)

    Abdel-Rahman, Wamied; Podgorsak, Ervin B

    2005-02-01

    The growth of a radioactive daughter in neutron activation is commonly described with the saturation model that ignores the consumption of parent nuclei during the radio-activation process. This approach is not valid when radioactive sources with high specific activities are produced or when the particle fluence rates used are very high. Assuming a constant neutron fluence rate throughout the activation target, a neutron-activation model that accounts for the depletion in parent nuclei is introduced. This depletion model is governed by relationships similar to those describing the parent-daughter-granddaughter decay series, and, in contrast to the saturation model, correctly predicts the practical limit of the daughter specific activity, irrespective of the particle fluence rate. Also introduced is a neutron-activation model that in addition to parent depletion accounts for the neutron activation of daughter nuclei in situations where the cross section for this effect is high. The model is referred to as the depletion-activation model and it provides the most realistic description for the daughter specific activity in neutron activation. Three specific neutron activation examples of interest to medical physics are presented: activation of molybdenum-98 into molybdenum-99 described by the saturation model; activation of cobalt-59 into cobalt-60 described by the depletion model; and activation of iridium-191 into iridium-192 described by the depletion-activation model.

  6. Pain Sensitisation in Women with Active Rheumatoid Arthritis: A Comparative Cross-Sectional Study.

    Science.gov (United States)

    Vladimirova, Nora; Jespersen, Anders; Bartels, Else Marie; Christensen, Anton W; Bliddal, Henning; Danneskiold-Samsøe, Bente

    2015-01-01

    Objectives. In some rheumatoid arthritis (RA) patients, joint pain persists without signs of inflammation. This indicates that central pain sensitisation may play a role in the generation of chronic pain in a subgroup of RA. Our aim was to assess the degree of peripheral and central pain sensitisation in women with active RA compared to healthy controls (HC). Methods. 38 women with active RA (DAS28 > 2.6) and 38 female HC were included in, and completed, the study. Exclusion criteria were polyneuropathy, pregnancy, and no Danish language. Cuff Pressure Algometry measurements were carried out on the dominant lower leg. Pain threshold, pain tolerance, and pain sensitivity during tonic painful stimulation were recorded. Results. Women with active RA had significantly lower pain threshold (p < 0.01) and pain tolerance (p < 0.01) than HC. The mean temporal summation- (TS-) index in RA patients was 0.98 (SEM: 0.09) and 0.71 (SEM: 0.04) in HC (p < 0.01). Conclusion. Patients with active RA showed decreased pressure-pain threshold compared to HC. In addition, temporal summation of pressure-pain was increased, indicating central pain sensitization, at least in some patients. Defining this subgroup of patients may be of importance when considering treatment strategies.

  7. Pain Sensitisation in Women with Active Rheumatoid Arthritis: A Comparative Cross-Sectional Study

    Directory of Open Access Journals (Sweden)

    Nora Vladimirova

    2015-01-01

    Full Text Available Objectives. In some rheumatoid arthritis (RA patients, joint pain persists without signs of inflammation. This indicates that central pain sensitisation may play a role in the generation of chronic pain in a subgroup of RA. Our aim was to assess the degree of peripheral and central pain sensitisation in women with active RA compared to healthy controls (HC. Methods. 38 women with active RA (DAS28>2.6 and 38 female HC were included in, and completed, the study. Exclusion criteria were polyneuropathy, pregnancy, and no Danish language. Cuff Pressure Algometry measurements were carried out on the dominant lower leg. Pain threshold, pain tolerance, and pain sensitivity during tonic painful stimulation were recorded. Results. Women with active RA had significantly lower pain threshold (p<0.01 and pain tolerance (p<0.01 than HC. The mean temporal summation- (TS- index in RA patients was 0.98 (SEM: 0.09 and 0.71 (SEM: 0.04 in HC (p<0.01. Conclusion. Patients with active RA showed decreased pressure-pain threshold compared to HC. In addition, temporal summation of pressure-pain was increased, indicating central pain sensitization, at least in some patients. Defining this subgroup of patients may be of importance when considering treatment strategies.

  8. Speech recognition in noise with active and passive hearing protectors: a comparative study.

    Science.gov (United States)

    Bockstael, Annelies; De Coensel, Bert; Botteldooren, Dick; D'Haenens, Wendy; Keppler, Hannah; Maes, Leen; Philips, Birgit; Swinnen, Freya; Bart, Vinck

    2011-06-01

    The perceived negative influence of standard hearing protectors on communication is a common argument for not wearing them. Thus, "augmented" protectors have been developed to improve speech intelligibility. Nevertheless, their actual benefit remains a point of concern. In this paper, speech perception with active earplugs is compared to standard passive custom-made earplugs. The two types of active protectors included amplify the incoming sound with a fixed level or to a user selected fraction of the maximum safe level. For the latter type, minimal and maximal amplification are selected. To compare speech intelligibility, 20 different speech-in-noise fragments are presented to 60 normal-hearing subjects and speech recognition is scored. The background noise is selected from realistic industrial noise samples with different intensity, frequency, and temporal characteristics. Statistical analyses suggest that the protectors' performance strongly depends on the noise condition. The active protectors with minimal amplification outclass the others for the most difficult and the easiest situations, but they also limit binaural listening. In other conditions, the passive protectors clearly surpass their active counterparts. Subsequently, test fragments are analyzed acoustically to clarify the results. This provides useful information for developing prototypes, but also indicates that tests with human subjects remain essential. © 2011 Acoustical Society of America

  9. Comparative Study of Chemical Composition and Biological Activity of Yellow, Green, Brown, and Red Brazilian Propolis

    Science.gov (United States)

    Machado, Christiane Schineider; Mokochinski, João Benhur; de Lira, Tatiana Onofre; de Oliveira, Fátima de Cassia Evangelista; Cardoso, Magda Vieira; Ferreira, Roseane Guimarães; Sawaya, Alexandra Christine Helena Frankland; Ferreira, Antonio Gilberto; Pessoa, Cláudia; Cuesta-Rubio, Osmany; Monteiro, Marta Chagas; de Campos, Mônica Soares

    2016-01-01

    The chemical composition and biological activity of a sample of yellow propolis from Mato Grosso do Sul, Brazil (EEP-Y MS), were investigated for the first time and compared with green, brown, and red types of Brazilian propolis and with a sample of yellow propolis from Cuba. Overall, EEP-Y MS had different qualitative chemical profiles, as well as different cytotoxic and antimicrobial activities when compared to the other types of propolis assessed in this study and it is a different chemotype of Brazilian propolis. Absence of phenolic compounds and the presence of mixtures of aliphatic compounds in yellow propolis were determined by analysing 1H-NMR spectra and fifteen terpenes were identified by GC-MS. EEP-Y MS showed cytotoxic activity against human tumour strain OVCAR-8 but was not active against Gram-negative or Gram-positive bacteria. Our results confirm the difficulty of establishing a uniform quality standard for propolis from diverse geographical origins. The most appropriate pharmacological applications of yellow types of propolis must be further investigated. PMID:27525023

  10. Effects of an occlusal splint compared with cognitive-behavioral treatment on sleep bruxism activity.

    Science.gov (United States)

    Ommerborn, Michelle A; Schneider, Christine; Giraki, Maria; Schäfer, Ralf; Handschel, Jörg; Franz, Matthias; Raab, Wolfgang H-M

    2007-02-01

    The impact of an occlusal splint (OS) compared with cognitive-behavioral treatment (CBT) on the management of sleep bruxism (SB) has been poorly investigated. The aim of this study was to evaluate the efficacy of an OS with CBT in SB patients. Following a randomized assignment, the OS group consisted of 29, and the CBT group of 28, SB patients. The CBT comprised problem-solving, progressive muscle relaxation, nocturnal biofeedback, and training of recreation and enjoyment. The treatment took place over a period of 12 wk, and the OS group received an OS over the same time period. Both groups were examined pretreatment, post-treatment, and at 6 months of follow-up for SB activity, self-assessment of SB activity and associated symptoms, psychological impairment, and individual stress-coping strategies. The analyses demonstrated a significant reduction in SB activity, self-assessment of SB activity, and psychological impairment, as well as an increase of positive stress-coping strategies in both groups. However, the effects were small and no group-specific differences were seen in any dependent variable. This is an initial attempt to compare CBT and OS in SB patients, and the data collected substantiate the need for further controlled evaluations, using a three-group randomized design with repeated measures to verify treatment effects.

  11. Comparative Study of Chemical Composition and Biological Activity of Yellow, Green, Brown, and Red Brazilian Propolis.

    Science.gov (United States)

    Machado, Christiane Schineider; Mokochinski, João Benhur; de Lira, Tatiana Onofre; de Oliveira, Fátima de Cassia Evangelista; Cardoso, Magda Vieira; Ferreira, Roseane Guimarães; Sawaya, Alexandra Christine Helena Frankland; Ferreira, Antonio Gilberto; Pessoa, Cláudia; Cuesta-Rubio, Osmany; Monteiro, Marta Chagas; de Campos, Mônica Soares; Torres, Yohandra Reyes

    2016-01-01

    The chemical composition and biological activity of a sample of yellow propolis from Mato Grosso do Sul, Brazil (EEP-Y MS), were investigated for the first time and compared with green, brown, and red types of Brazilian propolis and with a sample of yellow propolis from Cuba. Overall, EEP-Y MS had different qualitative chemical profiles, as well as different cytotoxic and antimicrobial activities when compared to the other types of propolis assessed in this study and it is a different chemotype of Brazilian propolis. Absence of phenolic compounds and the presence of mixtures of aliphatic compounds in yellow propolis were determined by analysing (1)H-NMR spectra and fifteen terpenes were identified by GC-MS. EEP-Y MS showed cytotoxic activity against human tumour strain OVCAR-8 but was not active against Gram-negative or Gram-positive bacteria. Our results confirm the difficulty of establishing a uniform quality standard for propolis from diverse geographical origins. The most appropriate pharmacological applications of yellow types of propolis must be further investigated.

  12. Comparative Study of Chemical Composition and Biological Activity of Yellow, Green, Brown, and Red Brazilian Propolis

    Directory of Open Access Journals (Sweden)

    Christiane Schineider Machado

    2016-01-01

    Full Text Available The chemical composition and biological activity of a sample of yellow propolis from Mato Grosso do Sul, Brazil (EEP-Y MS, were investigated for the first time and compared with green, brown, and red types of Brazilian propolis and with a sample of yellow propolis from Cuba. Overall, EEP-Y MS had different qualitative chemical profiles, as well as different cytotoxic and antimicrobial activities when compared to the other types of propolis assessed in this study and it is a different chemotype of Brazilian propolis. Absence of phenolic compounds and the presence of mixtures of aliphatic compounds in yellow propolis were determined by analysing 1H-NMR spectra and fifteen terpenes were identified by GC-MS. EEP-Y MS showed cytotoxic activity against human tumour strain OVCAR-8 but was not active against Gram-negative or Gram-positive bacteria. Our results confirm the difficulty of establishing a uniform quality standard for propolis from diverse geographical origins. The most appropriate pharmacological applications of yellow types of propolis must be further investigated.

  13. A comparative study of graph-based, eikonal, and monodomain simulations for the estimation of cardiac activation times.

    Science.gov (United States)

    Wallman, Mikael; Smith, Nicolas P; Rodriguez, Blanca

    2012-06-01

    The bidomain and monodomain equations are well established as the standard set of equations for the simulation of cardiac electrophysiological behavior. However, the computational cost of detailed bidomain/monodomain simulations limits their applicability in scenarios where a large number of simulations needs to be performed (e.g., parameter estimation). In this study, we present a graph-based method, which relies on point-to-point path finding to estimate activation times for single points in cardiac tissue with minimal computational costs. To validate our approach, activation times are compared to monodomain simulation results for an anatomically based rabbit ventricular model, incorporating realistic fiber orientation and conduction heterogeneities. Differences in activation times between the graph-based method and monodomain results are less than 10% of the total activation time, and computational performance is orders of magnitude faster with the proposed method when calculating activation times at single points. These results suggest that the graph-based method is well suited for estimating activation times when the need for fast performance justifies a limited loss of accuracy.

  14. Comparative antipyretic activity of methanolic extracts of some species of Amaranthus

    Institute of Scientific and Technical Information of China (English)

    Bagepalli Srinivas Ashok Kumar; Kuruba Lakshman; Jayaveera KN

    2011-01-01

    Objective: To provide scientific validation for the antipyretic activities of Amaranthus viridis (Linn.), Amaranthus caudatus (Linn.) and Amaranthus spinosus (Linn.). Methods: The antipyretic activity of methanol extracts of all three plants at doses of 200 and 400 mg/kg was investigated by yeast induced pyrexia in rats. Paracetamol (150 mg/kg, p.o.) was used as reference drug and control group received distilled water. Rectal temperatures of all the rats were recorded and compared at 19 h, immediately before extract or vehicle or paracetamol administration, and again at 1 h interval up to 24 h by thermal probe Eliab themistor thermometer. Results: At 400 mg/kg dose all the three methanolic extracts showed significant (P<0.01) reduction in yeast provoked elevated temperature as compared with that of standard drug paracetamol, whereas 200 mg/kg dose is less effective when compared with higher dose (P<0.05). Conclusions: The results show that methanol extract of three plants of Amaranthus possesses a significant antipyretic effect in maintaining reducing yeast-induced elevated body temperature in rats and their effects were comparable to that of the standard antipyretic drug paracetamol.

  15. Comparative postantibacterial activities of pefloxacin, ciprofloxacin, and ofloxacin against intracellular multiplication of Legionella pneumophila serogroup 1.

    OpenAIRE

    Rajagopalan-Levasseur, P; Dournon, E; Dameron, G; Vilde, J. L.; Pocidalo, J J

    1990-01-01

    The inhibitory and postantibacterial activities of pefloxacin, ciprofloxacin, and ofloxacin against virulent Legionella pneumophila serogroup 1 were evaluated in cell-free and cellular models. In the absence of macrophages (with the tissue culture medium alone), bacterial numbers remained unchanged at 24 h in the presence of 0.1 microgram of pefloxacin, ciprofloxacin, or ofloxacin per ml and 1.0 microgram of pefloxacin per ml, whereas they were reduced in the presence of 1.0 microgram of cipr...

  16. Cardiac modeling using active appearance models and morphological operators

    Science.gov (United States)

    Pfeifer, Bernhard; Hanser, Friedrich; Seger, Michael; Hintermueller, Christoph; Modre-Osprian, Robert; Fischer, Gerald; Muehlthaler, Hannes; Trieb, Thomas; Tilg, Bernhard

    2005-04-01

    We present an approach for fast reconstructing of cardiac myocardium and blood masses of a patient's heart from morphological image data, acquired either MRI or CT, in order to estimate numerically the spread of electrical excitation in the patient's atria and ventricles. The approach can be divided into two main steps. During the first step the ventricular and atrial blood masses are extracted employing Active Appearance Models (AAM). The left and right ventricular blood masses are segmented automatically after providing the positions of the apex cordis and the base of the heart. Because of the complex geometry of the atria the segmentation process of the atrial blood masses requires more information as the ventricular blood mass segmentation process of the ventricles. We divided, for this reason, the left and right atrium into three divisions of appearance. This proved sufficient for the 2D AAM model to extract the target blood masses. The base of the heart, the left upper and left lower pulmonary vein from its first up to its last appearance in the image stack, and the right upper and lower pulmonary vein have to be marked. After separating the volume data into these divisions the 2D AAM search procedure extracts the blood masses which are the main input for the second and last step in the myocardium extraction pipeline. This step uses morphologically-based operations in order to extract the ventricular and atrial myocardium either directly by detecting the myocardium in the volume block or by reconstructing the myocardium using mean model information, in case the algorithm fails to detect the myocardium.

  17. Comparative characterization of the leukocidic and hemolytic activity of Moraxella bovis.

    Science.gov (United States)

    Hoien-Dalen, P S; Rosenbusch, R F; Roth, J A

    1990-02-01

    The cytotoxic effect of Moraxella bovis 118F on bovine neutrophils was evaluated and characterized by use of a 51Cr release assay. Neutrophils harvested from healthy adult cattle were labeled with 51Cr. The leukocidic activity produced by M bovis 118F, a hemolytic strain of M bovis, was heat-labile. A live culture of strain 118F, at a ratio of 100 bacteria/neutrophil, released 97.7% of the 51Cr from labeled neutrophils. Neither a heat-killed preparation of M bovis 118F nor a live or heat-killed preparation of M bovis IBH63 (a nonhemolytic and nonpathogenic strain) induced significant (P greater than 0.05) release of 51Cr. Moraxella bovis 118F broth culture filtrates prepared for evaluation of leukocidic activity also were evaluated for hemolytic activity. These 2 toxic activities had several characteristics in common. Both were filterable, heat-labile, produced by a hemolytic strain, and were released during early logarithmic phase growth from broth cultures. Leukocidic and hemolytic activities were protected from degradation by phenylmethyl sulfonyl fluoride, a serine protease inhibitor. Leukocidic and hemolytic activities were dependent on calcium ions. Filtrate resulted in 54.1% 51Cr release from labeled neutrophils and contained 646.7 hemolytic U/ml, respectively, when saline (0.85% NaCl) + 10 mM CaCl2 solution was used as diluent. Neither saline solution nor saline + 10 mM MgCl2 solution supported leukocidic or hemolytic activity. Serum, obtained from several calves 10 to 38 days after M bovis inoculation, substantially neutralized leukocidic and hemolytic activities, compared with paired preinoculation serum samples.(ABSTRACT TRUNCATED AT 250 WORDS)

  18. Physical activity of young overweight and obese children: parent reports of child activity level compared with objective measures.

    Science.gov (United States)

    Small, Leigh; Bonds-McClain, Darya; Gannon, Alex M

    2013-05-01

    The purpose of this study was to compare objectively measured physical activity (PA) and parent-reported assessments of the children's PA in an overweight/obese child sample. A total of 67 child-parent dyads were recruited for study participation. Child anthropometric measures and parent-reported questionnaires were completed, and then PA was measured by accelerometers for 48 consecutive hours. These children demonstrated moderate-to-vigorous PA for 17.32 min per day on average. The children spent 86.7% of their time in sedentary activities. Parents' reports of hyperactivity were significantly related to the objectively measured PA; however, the parents significantly overestimated the average amount of time children spent in each activity level. These findings suggest that although parents may be able to generally characterize their child's PA, they may not be able to accurately report specific information and thus may struggle to identify clear activity goals for their child and/or be unable to assess intervention effects.

  19. A comparative study of carbon dioxide adsorption on multi-walled carbon nanotubes versus activated charcoal

    Science.gov (United States)

    Khalili, S.; Ghoreyshi, A. A.; Jahanshahi, M.; Davoodi, M.

    2012-09-01

    In this study, the quilibrium adsorption of CO2 on activated charcoal and multi-walled carbon nanotube (MWCNT) were experimentally investigated at temperature range of 298-318 K and pressures up to 40 bars. The maximum storage capacity for both materials was obtained at lowest temperature and highest pressure under study. The amount of CO2 adsorbed on MWCNT is 2 times higher than that of activated Charcoal whereas the specific surface area of activated carbon is aboute 2 times higher than MWNT. The experimental data of CO2 adsorption have been analyzed using different model isotherms such as the Freundlich and Langmuir. Heat of adsorption evaluated from a set of isotherms based on the Clausius-Clapeyron equation indicated physical nature of adsorption mechanism.

  20. Experimental and modelling results of a parallel-plate based active magnetic regenerator

    DEFF Research Database (Denmark)

    Tura, A.; Nielsen, Kaspar Kirstein; Rowe, A.

    2012-01-01

    The performance of a permanent magnet magnetic refrigerator (PMMR) using gadolinium parallel plates is described. The configuration and operating parameters are described in detail. Experimental results are compared to simulations using an established twodimensional model of an active magnetic...

  1. Exploration of freely available web-interfaces for comparative homology modelling of microbial proteins.

    Science.gov (United States)

    Nema, Vijay; Pal, Sudhir Kumar

    2013-01-01

    This study was conducted to find the best suited freely available software for modelling of proteins by taking a few sample proteins. The proteins used were small to big in size with available crystal structures for the purpose of benchmarking. Key players like Phyre2, Swiss-Model, CPHmodels-3.0, Homer, (PS)2, (PS)(2)-V(2), Modweb were used for the comparison and model generation. Benchmarking process was done for four proteins, Icl, InhA, and KatG of Mycobacterium tuberculosis and RpoB of Thermus Thermophilus to get the most suited software. Parameters compared during analysis gave relatively better values for Phyre2 and Swiss-Model. This comparative study gave the information that Phyre2 and Swiss-Model make good models of small and large proteins as compared to other screened software. Other software was also good but is often not very efficient in providing full-length and properly folded structure.

  2. Comparative analysis of mathematical models of the matrix photodetector used in digital holography

    Science.gov (United States)

    Grebenyuk, K. A.

    2017-08-01

    It is established, that in modern works on digital holography, three fundamentally different mathematical models of a matrix photodetector are used. Comparative analysis of these models, including analysis of the formula of each model and test calculations, has been conducted. The possibility of using these models to account for the influence of geometrical parameters of a matrix photodetector on the properties of recorded digital holograms is considered.

  3. The Fracture Mechanical Markov Chain Fatigue Model Compared with Empirical Data

    DEFF Research Database (Denmark)

    Gansted, L.; Brincker, Rune; Hansen, Lars Pilegaard

    The applicability of the FMF-model (Fracture Mechanical Markov Chain Fatigue Model) introduced in Gansted, L., R. Brincker and L. Pilegaard Hansen (1991) is tested by simulations and compared with empirical data. Two sets of data have been used, the Virkler data (aluminium alloy) and data...... that the FMF-model gives adequate description of the empirical data using model parameters characteristic of the material....

  4. Comparing clouds and their seasonal variations in 10 atmospheric general circulation models with satellite measurements

    OpenAIRE

    Zhang, M.; Lin, W.; Klein, S.; J. Bacmeister; Bony, S.; Cederwall, R.; Del Genio, A; Hack, J.; Loeb, N.; Lohmann, U.; P. Minnis; Musat, I.; Pincus, R; Stier, P.; Suarez, M.

    2005-01-01

    To assess the current status of climate models in simulating clouds, basic cloud climatologies from ten atmospheric general circulation models are compared with satellite measurements from the International Satellite Cloud Climatology Project (ISCCP) and the Clouds and Earth's Radiant Energy System (CERES) program. An ISCCP simulator is employed in all models to facilitate the comparison. Models simulated a four-fold difference in high-top clouds. There are also, however, large uncertainties ...

  5. EMG-normalised kinase activation during exercise is higher in human gastrocnemius compared to soleus muscle.

    Directory of Open Access Journals (Sweden)

    Thomas E Jensen

    Full Text Available In mice, certain proteins show a highly confined expression in specific muscle groups. Also, resting and exercise/contraction-induced phosphorylation responses are higher in rat skeletal muscle with low mitochondrial content compared to muscles with high mitochondrial content, possibly related to differential reactive oxygen species (ROS-scavenging ability or resting glycogen content. To evaluate these parameters in humans, biopsies from soleus, gastrocnemius and vastus lateralis muscles were taken before and after a 45 min inclined (15% walking exercise bout at 69% VO2(max aimed at simultaneously activating soleus and gastrocnemius in a comparable dynamic work-pattern. Hexokinase II and GLUT4 were 46-59% and 26-38% higher (p<0.05 in soleus compared to the two other muscles. The type I muscle fiber percentage was highest in soleus and lowest in vastus lateralis. No differences were found in protein expression of signalling proteins (AMPK subunits, eEF2, ERK1/2, TBC1D1 and 4, mitochondrial markers (F1 ATPase and COX1 or ROS-handling enzymes (SOD2 and catalase. Gastrocnemius was less active than soleus measured as EMG signal and glycogen use yet gastrocnemius displayed larger increases than soleus in phosphorylation of AMPK Thr172, eEF2 Thr56 and ERK 1/2 Thr202/Tyr204 when normalised to the mean relative EMG-signal. In conclusion, proteins with muscle-group restricted expression in mice do not show this pattern in human lower extremity muscle groups. Nonetheless the phosphorylation-response is greater for a number of kinase signalling pathways in human gastrocnemius than soleus at a given activation-intensity. This may be due to the combined subtle effects of a higher type I muscle fiber content and higher training status in soleus compared to gastrocnemius muscle.

  6. Identification of contrastive and comparable school neighborhoods for childhood obesity and physical activity research

    Directory of Open Access Journals (Sweden)

    Christoffel Katherine

    2006-03-01

    Full Text Available Abstract The neighborhood social and physical environments are considered significant factors contributing to children's inactive lifestyles, poor eating habits, and high levels of childhood obesity. Understanding of neighborhood environmental profiles is needed to facilitate community-based research and the development and implementation of community prevention and intervention programs. We sought to identify contrastive and comparable districts for childhood obesity and physical activity research studies. We have applied GIS technology to manipulate multiple data sources to generate objective and quantitative measures of school neighborhood-level characteristics for school-based studies. GIS technology integrated data from multiple sources (land use, traffic, crime, and census tract and available social and built environment indicators theorized to be associated with childhood obesity and physical activity. We used network analysis and geoprocessing tools within a GIS environment to integrate these data and to generate objective social and physical environment measures for school districts. We applied hierarchical cluster analysis to categorize school district groups according to their neighborhood characteristics. We tested the utility of the area characterizations by using them to select comparable and contrastive schools for two specific studies. Results We generated school neighborhood-level social and built environment indicators for all 412 Chicago public elementary school districts. The combination of GIS and cluster analysis allowed us to identify eight school neighborhoods that were contrastive and comparable on parameters of interest (land use and safety for a childhood obesity and physical activity study. Conclusion The combination of GIS and cluster analysis makes it possible to objectively characterize urban neighborhoods and to select comparable and/or contrasting neighborhoods for community-based health studies.

  7. Comparing mirror neuron system activity between sporadic and familial cases of schizophrenia.

    Science.gov (United States)

    Mitra, Sayantanava; Nizamie, S Haque; Goyal, Nishant; Tikka, Sai Krishna; Kavoor, Anjana Rao

    2016-06-01

    Schizophrenia is a heterogenous disorder, and has often been subtyped on the basis of family history of psychotic disorders. Compared to those without, a positive family history is associated with an earlier age of onset, greater structural brain abnormalities and poorer clinical course. Given recent emphasis on mirror neuron system (MNS) in attempting to explain psychopathology in schizophrenia; present analysis tried to tease out differences in MNS functioning between these two groups. With ethical approval, 10 consenting right-handed patients with schizophrenia (ICD-10-DCR; M=8; Drug-naïve=2) were recruited and divided into two groups of five each (M=4, F=1): those with (age 29.40±5.85 years, duration of illness 50.80±30.84 months) and without (age 29.60±5.77 years, duration of illness 43.20±43.76 months) family history of schizophrenic illness (group difference p>0.05). MNS activity was assessed using event-related desynchronization of EEG Mu waves in response to biological motion on 192-channel EEG Neurofax EEG-1100K. On comparison, while patients had significantly lower mu suppression compared to controls (pschizophrenia groups did not differ between themselves, neither on MNS activity nor on psychopathology (p>0.05). Present study replicates finding of a dysfunctional MNS in schizophrenia patients, and represents a preliminary attempt at comparing two groups of symptomatic schizophrenia patients. In both these groups, MNS dysfunctions were comparable, and commensurate with respect to psychopathology. Thus, MNS dysfunction in schizophrenia might either be inherited or acquired. However, this abnormality forms a common base, and ultimate vulnerability marker, for development of psychopathology during active disease states. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. Comparative toxicity of chlorpyrifos and its oxon derivatives to soil microbial activity by combined methods.

    Science.gov (United States)

    Wang, Fei; Yao, Jun; Chen, Huilun; Chen, Ke; Trebse, Polonca; Zaray, Gyula

    2010-01-01

    The inhibitory effects of the pesticide Chlorpyrifos (CPF) and its oxon derivative (CPO) on soil microbial activity were evaluated through the measurement of metabolic parameters and the microbial urease enzyme. The thermodynamic parameters related to microbial activity were measured and recorded as power-time curves. Microbial growth rate constant k, total heat evolution Q(T), metabolic enthalpy DeltaH(met), mass specific heat rate J(Q/S), microbial biomass C and inhibitory ratio I were calculated. They showed the linear relationship with doses of CPF and CPO. Thereinto, the linear correlations, k versus biomass C and DeltaH(met) versus biomass C, elucidated that k and DeltaH(met) were growth yield dependent. In this work, 20% inhibitory ratio IC(20) was obtained with 9.8 microg g(-1) for CPF and 0.37 microg g(-1) CPO, meaning that the acute toxicity of CPO was 26 times that of CPF, since the CPO had more potent toxicity to living organism due to its active functional group. Comparing the change tendency of DeltaH(met) and other parameter, the values almost kept constant when exposure to CPF (<5.0 microg g(-1)). It illustrates that individual reacted to stress resulted from environment change by shifting resources from other biological activities (such as reproduction or growth) toward survival to some extent. Urease activity responses in relation to the CPF and CPO exposure were observed and consistent with above thermodynamic parameters.

  9. Comparative analysis on the distribution of protease activities among fruits and vegetable resources.

    Science.gov (United States)

    Sun, Qian; Zhang, Bin; Yan, Qiao-Juan; Jiang, Zheng-Qiang

    2016-12-15

    In this study, a comparative analysis on the distribution of protease activities among 90 plant resources, including fruits and vegetables, has been performed. Protease activities of plant extracts were assayed at different pH values (pH 3.0, pH 7.5 and pH 10.5) using casein as a substrate. Ten fruits and thirteen vegetables show protease activities above 10U/g. Pineapple, fig and papaya, which are used for commercial protease production, exhibited high protease activities. Additionally, high protease activities were detected in kiwifruit (28.8U/g), broccoli (16.9U/g), ginger (16.6U/g), leek (32.7U/g) and red pepper (15.8U/g) at different pH values. SDS-PAGE and zymograms confirmed that various types of proteases existed in the five plant extracts and might be explored. Furthermore, five plant extracts were treated by different protease inhibitors. These results show that there are still many plant resources unexplored, which may be promising candidates for plant-derived protease production.

  10. Comparative study of PEM fuel cell models for integration in propulsion systems of urban public transport

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, P.; Fernandez, L.M.; Garcia, C.A. [Department of Electrical Engineering, University of Cadiz, EPS Algeciras, Avda. Ramon Puyol, s/n. 11202 Algeciras (Cadiz) (Spain); Jurado, F. [Department of Electrical Engineering, University of Jaen, EPS Linares, C/ Alfonso X, n 28. 23700 Linares (Jaen) (Spain)

    2010-12-15

    Steady state and dynamic simulations are performed in order to compare the models. Considering the external response of FC system integrated in the tramway hybrid system, both reduced models show similar results with an important reduction of computation time with respect to the complete model. However, the reduced model 1 shows better results than the reduced model 2 when representing the internal behaviour of FC system, so that this model is considered the most appropriate for propulsion system applications. (Copyright copyright 2010 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  11. Jackson System Development, Entity-relationship Analysis and Data Flow Models: a comparative study

    OpenAIRE

    Wieringa, R.J.

    1994-01-01

    This report compares JSD with ER modeling and data flow modeling. It is shown that JSD can be combined with ER modeling and that the result is a richer method than either of the two. The resulting method can serve as a basis for a pratical object-oriented modeling method and has some resemblance to parts of well-known methods, like OMT. It is also argued that JSD and data flow modeling rest on opposite philosophies and cannot be combined in one modeling effort. This is illustrated by transfor...

  12. Comparing predictive validity of four ballistic swing phase models of human walking.

    Science.gov (United States)

    Selles, R W; Bussmann, J B; Wagenaar, R C; Stam, H J

    2001-09-01

    It is unclear to what extent ballistic walking models can be used to qualitatively predict the swing phase at comfortable walking speed. Different study findings regarding the accuracy of the predictions of the swing phase kinematics may have been caused by differences in (1) kinematic input, (2) model characteristics (e.g. the number of segments), and (3) evaluation criteria. In the present study, the predictive validity of four ballistic swing phase models was evaluated and compared, that is, (1) the ballistic walking model as originally introduced by Mochon and McMahon, (2) an extended version of this model in which heel-off of the stance leg is added, (3) a double pendulum model, consisting of a two-segment swing leg with a prescribed hip trajectory, and (4) a shank pendulum model consisting of a shank and rigidly attached foot with a prescribed knee trajectory. The predictive validity was evaluated by comparing the outcome of the model simulations with experimentally derived swing phase kinematics of six healthy subjects. In all models, statistically significant differences were found between model output and experimental data. All models underestimated swing time and step length. In addition, statistically significant differences were found between the output of the different models. The present study shows that although qualitative similarities exist between the ballistic models and normal gait at comfortable walking speed, these models cannot adequately predict swing phase kinematics.

  13. Modeling Mixed Bicycle Traffic Flow: A Comparative Study on the Cellular Automata Approach

    Directory of Open Access Journals (Sweden)

    Dan Zhou

    2015-01-01

    Full Text Available Simulation, as a powerful tool for evaluating transportation systems, has been widely used in transportation planning, management, and operations. Most of the simulation models are focused on motorized vehicles, and the modeling of nonmotorized vehicles is ignored. The cellular automata (CA model is a very important simulation approach and is widely used for motorized vehicle traffic. The Nagel-Schreckenberg (NS CA model and the multivalue CA (M-CA model are two categories of CA model that have been used in previous studies on bicycle traffic flow. This paper improves on these two CA models and also compares their characteristics. It introduces a two-lane NS CA model and M-CA model for both regular bicycles (RBs and electric bicycles (EBs. In the research for this paper, many cases, featuring different values for the slowing down probability, lane-changing probability, and proportion of EBs, were simulated, while the fundamental diagrams and capacities of the proposed models were analyzed and compared between the two models. Field data were collected for the evaluation of the two models. The results show that the M-CA model exhibits more stable performance than the two-lane NS model and provides results that are closer to real bicycle traffic.

  14. Dynamic viscosity modeling of methane plus n-decane and methane plus toluene mixtures: Comparative study of some representative models

    DEFF Research Database (Denmark)

    Baylaucq, A.; Boned, C.; Canet, X.;

    2005-01-01

    .15 and for several methane compositions. Although very far from real petroleum fluids, these mixtures are interesting in order to study the potential of extending various models to the simulation of complex fluids with asymmetrical components (light/heavy hydrocarbon). These data (575 data points) have been...... discussed in the framework of recent representative models (hard sphere scheme, friction theory, and free volume model) and with mixing laws and two empirical models (particularly the LBC model which is commonly used in petroleum engineering, and the self-referencing model). This comparative study shows...

  15. Food reward in active compared to inactive men: Roles for gastric emptying and body fat.

    Science.gov (United States)

    Horner, Katy M; Finlayson, Graham; Byrne, Nuala M; King, Neil A

    2016-06-01

    Habitual exercise could contribute to weight management by altering processes of food reward via the gut-brain axis. We investigated hedonic processes of food reward in active and inactive men and characterised relationships with gastric emptying and body fat. Forty-four men (active: n=22; inactive: n=22, BMI range 21-36kg/m(2); percent fat mass range 9-42%) were studied. Participants were provided with a standardised fixed breakfast and an ad libitum lunch meal 5h later. Explicit liking, implicit wanting and preference among high-fat, low-fat, sweet and savoury food items were assessed immediately post-breakfast (fed state) and again pre-lunch (hungry state) using the Leeds Food Preference Questionnaire. Gastric emptying was assessed by (13)C-octanoic acid breath test. Active individuals exhibited a lower liking for foods overall and a greater implicit wanting for low-fat savoury foods in the fed state, compared to inactive men. Differences in the fed state remained significant after adjusting for percent fat mass. Active men also had a greater increase in liking for savoury foods in the interval between breakfast and lunch. Faster gastric emptying was associated with liking for savoury foods and with an increase in liking for savoury foods in the postprandial interval. In contrast, greater implicit wanting for high-fat foods was associated with slower gastric emptying. These associations were independent of each other, activity status and body fat. In conclusion, active and inactive men differ in processes of food reward. The rate of gastric emptying may play a role in the association between physical activity status and food reward, via the gut-brain axis.

  16. Comparing effects of active and passive restoration on the Middle Fork John Day River, NE Oregon

    Science.gov (United States)

    McDowell, P. F.; Goslin, M.

    2015-12-01

    Since 2000, cattle grazing has been eliminated on over 14 km of the upper Middle Fork John Day. Starting in 2008, active restoration (log structures with dug pools, woody vegetation planting, and modifications to increase channel-floodplain hydrologic connectivity) was implemented on nearly 6 km within the cattle exclosure length. Implementation of active and passive restoration strategies in the same and adjacent reaches allows comparison of these two approaches. We have been monitoring these reaches since 2008. Unexpectedly in response to grazing exclosure, a native sedge, Carex nudata (torrent sedge), has exploded in population. C. nudata grows in the active channel, anchoring itself tightly to the gravel-cobble river bed with a dense root network. As a result, C. nudata has changed erosion and sedimentation patterns including bank erosion, channel bed scour, and island formation. We present data on fish cover increases due to C. nudata and log structures, and on channel complexity before and after restoration. Both active and passive restorations are increasing channel complexity and juvenile fish cover, although in different ways. Fish cover provided by active and passive restoration are similar in area but different in depth and position, with C. nudata fish cover generally shallower and partly mid-channel. Residual pool depth is larger in log structure pools than in C. nudata scour pools, but C. nudata pools are more numerous in some reaches. By producing frequent, small scour features and small islands, it can be argued that C. nudata is increasing hydraulic complexity more than the large, meander-bend pools at log structures, but this is hard to quantify. C. nudata has also stabilized active bars, perhaps changing the bedload sediment budget. Positive habitat benefits of active restoration appear to be greater in the short term, but over the long term (20 years or more) effects of C. nudata may be comparable or greater.

  17. Comparing Models of Helper Behavior to Actual Practice in Telephone Crisis Intervention: A Silent Monitoring Study of Calls to the U.S. 1-800-SUICIDE Network

    Science.gov (United States)

    Mishara, Brian L.; Chagnon, Francois; Daigle, Marc; Balan, Bogdan; Raymond, Sylvaine; Marcoux, Isabelle; Bardon, Cecile; Campbell, Julie K.; Berman, Alan

    2007-01-01

    Models of telephone crisis intervention in suicide prevention and best practices were developed from a literature review and surveys of crisis centers. We monitored 2,611 calls to 14 centers using reliable behavioral ratings to compare actual interventions with the models. Active listening and collaborative problem-solving models describe help…

  18. 3D active workspace of human hand anatomical model

    Directory of Open Access Journals (Sweden)

    Ungureanu Loredana

    2007-05-01

    Full Text Available Abstract Background If the model of the human hand is created with accuracy by respecting the type of motion provided by each articulation and the dimensions of articulated bones, it can function as the real organ providing the same motions. Unfortunately, the human hand is hard to model due to its kinematical chains submitted to motion constraints. On the other hand, if an application does not impose a fine manipulation it is not necessary to create a model as complex as the human hand is. But always the hand model has to perform a certain space of motions in imposed workspace architecture no matter what the practical application does. Methods Based on Denavit-Hartenberg convention, we conceived the kinematical model of the human hand, having in mind the structure and the behavior of the natural model. We obtained the kinematical equations describing the motion of every fingertip with respect to the general coordinate system, placed on the wrist. For every joint variable, a range of motion was established. Dividing these joint variables to an appropriate number of intervals and connecting them, the complex surface bordering the active hand model workspace was obtained. Results Using MATLAB 7.0, the complex surface described by fingertips, when hand articulations are all simultaneously moving, was obtained. It can be seen that any point on surface has its own coordinates smaller than the maximum length of the middle finger in static position. Therefore, a sphere having the centre in the origin of the general coordinate system and the radius which equals this length covers the represented complex surface. Conclusion We propose a human hand model that represents a new solution compared to the existing ones. This model is capable to make special movements like power grip and dexterous manipulations. During them, the fingertips do not exceed the active workspace encapsulated by determined surfaces. The proposed kinematical model can help to choose

  19. Comparative Antimicrobial Activities of Aerosolized Sodium Hypochlorite, Chlorine Dioxide, and Electrochemically Activated Solutions Evaluated Using a Novel Standardized Assay

    Science.gov (United States)

    Thorn, R. M. S.; Robinson, G. M.

    2013-01-01

    The main aim of this study was to develop a standardized experimental assay to enable differential antimicrobial comparisons of test biocidal aerosols. This study represents the first chlorine-matched comparative assessment of the antimicrobial activities of aerosolized sodium hypochlorite, chlorine dioxide, and electrochemically activated solution (ECAS) to determine their relative abilities to decontaminate various surface-associated health care-relevant microbial challenges. Standard microbiological challenges were developed by surface-associating typed Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus subtilis spores, or a clinical methicillin-resistant S. aureus (MRSA) strain on stainless steel, polypropylene, or fabric. All test coupons were subjected to 20-min biocidal aerosols of chlorine-matched (100 ppm) sodium hypochlorite, chlorine dioxide, or ECAS within a standard aerosolization chamber using a commercial humidifier under defined conditions. Biocidal treatment type and material surface had a significant effect on the number of microorganisms recovered from various material surfaces following treatment exposure. Under the conditions of the assay, the order of antimicrobial efficacy of biocidal aerosol treatment was as follows: ECAS > chlorine dioxide > sodium hypochlorite. For all biocides, greater antimicrobial reductions were seen when treating stainless steel and fabric than when treating plastic-associated microorganisms. The experimental fogging system and assay protocol designed within this study were shown capable of differentiating the comparative efficacies of multiple chlorine-matched biocidal aerosols against a spectrum of target organisms on a range of test surface materials and would be appropriate for testing other biocidal aerosol treatments or material surfaces. PMID:23459480

  20. Comparative antimicrobial activities of aerosolized sodium hypochlorite, chlorine dioxide, and electrochemically activated solutions evaluated using a novel standardized assay.

    Science.gov (United States)

    Thorn, R M S; Robinson, G M; Reynolds, D M

    2013-05-01

    The main aim of this study was to develop a standardized experimental assay to enable differential antimicrobial comparisons of test biocidal aerosols. This study represents the first chlorine-matched comparative assessment of the antimicrobial activities of aerosolized sodium hypochlorite, chlorine dioxide, and electrochemically activated solution (ECAS) to determine their relative abilities to decontaminate various surface-associated health care-relevant microbial challenges. Standard microbiological challenges were developed by surface-associating typed Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus subtilis spores, or a clinical methicillin-resistant S. aureus (MRSA) strain on stainless steel, polypropylene, or fabric. All test coupons were subjected to 20-min biocidal aerosols of chlorine-matched (100 ppm) sodium hypochlorite, chlorine dioxide, or ECAS within a standard aerosolization chamber using a commercial humidifier under defined conditions. Biocidal treatment type and material surface had a significant effect on the number of microorganisms recovered from various material surfaces following treatment exposure. Under the conditions of the assay, the order of antimicrobial efficacy of biocidal aerosol treatment was as follows: ECAS > chlorine dioxide > sodium hypochlorite. For all biocides, greater antimicrobial reductions were seen when treating stainless steel and fabric than when treating plastic-associated microorganisms. The experimental fogging system and assay protocol designed within this study were shown capable of differentiating the comparative efficacies of multiple chlorine-matched biocidal aerosols against a spectrum of target organisms on a range of test surface materials and would be appropriate for testing other biocidal aerosol treatments or material surfaces.

  1. Comparing large-scale computational approaches to epidemic modeling: Agent-based versus structured metapopulation models

    Directory of Open Access Journals (Sweden)

    Merler Stefano

    2010-06-01

    Full Text Available Abstract Background In recent years large-scale computational models for the realistic simulation of epidemic outbreaks have been used with increased frequency. Methodologies adapt to the scale of interest and range from very detailed agent-based models to spatially-structured metapopulation models. One major issue thus concerns to what extent the geotemporal spreading pattern found by different modeling approaches may differ and depend on the different approximations and assumptions used. Methods We provide for the first time a side-by-side comparison of the results obtained with a stochastic agent-based model and a structured metapopulation stochastic model for the progression of a baseline pandemic event in Italy, a large and geographically heterogeneous European country. The agent-based model is based on the explicit representation of the Italian population through highly detailed data on the socio-demographic structure. The metapopulation simulations use the GLobal Epidemic and Mobility (GLEaM model, based on high-resolution census data worldwide, and integrating airline travel flow data with short-range human mobility patterns at the global scale. The model also considers age structure data for Italy. GLEaM and the agent-based models are synchronized in their initial conditions by using the same disease parameterization, and by defining the same importation of infected cases from international travels. Results The results obtained show that both models provide epidemic patterns that are in very good agreement at the granularity levels accessible by both approaches, with differences in peak timing on the order of a few days. The relative difference of the epidemic size depends on the basic reproductive ratio, R0, and on the fact that the metapopulation model consistently yields a larger incidence than the agent-based model, as expected due to the differences in the structure in the intra-population contact pattern of the approaches. The age

  2. On Comparing NWP and Radar Nowcast Models for Forecasting of Urban Runoff

    DEFF Research Database (Denmark)

    Thorndahl, Søren Liedtke; Bøvith, T.; Rasmussen, Michael R.;

    2012-01-01

    The paper compares quantitative precipitation forecasts using weather radars and numerical weather prediction models. In order to test forecasts under different conditions, point-comparisons with quantitative radar precipitation estimates and raingauges are presented. Furthermore, spatial...

  3. Using Graph and Vertex Entropy to Compare Empirical Graphs with Theoretical Graph Models

    Directory of Open Access Journals (Sweden)

    Tomasz Kajdanowicz

    2016-09-01

    Full Text Available Over the years, several theoretical graph generation models have been proposed. Among the most prominent are: the Erdős–Renyi random graph model, Watts–Strogatz small world model, Albert–Barabási preferential attachment model, Price citation model, and many more. Often, researchers working with real-world data are interested in understanding the generative phenomena underlying their empirical graphs. They want to know which of the theoretical graph generation models would most probably generate a particular empirical graph. In other words, they expect some similarity assessment between the empirical graph and graphs artificially created from theoretical graph generation models. Usually, in order to assess the similarity of two graphs, centrality measure distributions are compared. For a theoretical graph model this means comparing the empirical graph to a single realization of a theoretical graph model, where the realization is generated from the given model using an arbitrary set of parameters. The similarity between centrality measure distributions can be measured using standard statistical tests, e.g., the Kolmogorov–Smirnov test of distances between cumulative distributions. However, this approach is both error-prone and leads to incorrect conclusions, as we show in our experiments. Therefore, we propose a new method for graph comparison and type classification by comparing the entropies of centrality measure distributions (degree centrality, betweenness centrality, closeness centrality. We demonstrate that our approach can help assign the empirical graph to the most similar theoretical model using a simple unsupervised learning method.

  4. Latitudinal variations in seasonal activity of influenza and respiratory syncytial virus (RSV: a global comparative review.

    Directory of Open Access Journals (Sweden)

    Kimberly Bloom-Feshbach

    Full Text Available There is limited information on influenza and respiratory syncytial virus (RSV seasonal patterns in tropical areas, although there is renewed interest in understanding the seasonal drivers of respiratory viruses.We review geographic variations in seasonality of laboratory-confirmed influenza and RSV epidemics in 137 global locations based on literature review and electronic sources. We assessed peak timing and epidemic duration and explored their association with geography and study settings. We fitted time series model to weekly national data available from the WHO influenza surveillance system (FluNet to further characterize seasonal parameters.Influenza and RSV activity consistently peaked during winter months in temperate locales, while there was greater diversity in the tropics. Several temperate locations experienced semi-annual influenza activity with peaks occurring in winter and summer. Semi-annual activity was relatively common in tropical areas of Southeast Asia for both viruses. Biennial cycles of RSV activity were identified in Northern Europe. Both viruses exhibited weak latitudinal gradients in the timing of epidemics by hemisphere, with peak timing occurring later in the calendar year with increasing latitude (P<0.03. Time series model applied to influenza data from 85 countries confirmed the presence of latitudinal gradients in timing, duration, seasonal amplitude, and between-year variability of epidemics. Overall, 80% of tropical locations experienced distinct RSV seasons lasting 6 months or less, while the percentage was 50% for influenza.Our review combining literature and electronic data sources suggests that a large fraction of tropical locations experience focused seasons of respiratory virus activity in individual years. Information on seasonal patterns remains limited in large undersampled regions, included Africa and Central America. Future studies should attempt to link the observed latitudinal gradients in

  5. Quantitative modeling of the ionospheric response to geomagnetic activity

    Directory of Open Access Journals (Sweden)

    T. J. Fuller-Rowell

    Full Text Available A physical model of the coupled thermosphere and ionosphere has been used to determine the accuracy of model predictions of the ionospheric response to geomagnetic activity, and assess our understanding of the physical processes. The physical model is driven by empirical descriptions of the high-latitude electric field and auroral precipitation, as measures of the strength of the magnetospheric sources of energy and momentum to the upper atmosphere. Both sources are keyed to the time-dependent TIROS/NOAA auroral power index. The output of the model is the departure of the ionospheric F region from the normal climatological mean. A 50-day interval towards the end of 1997 has been simulated with the model for two cases. The first simulation uses only the electric fields and auroral forcing from the empirical models, and the second has an additional source of random electric field variability. In both cases, output from the physical model is compared with F-region data from ionosonde stations. Quantitative model/data comparisons have been performed to move beyond the conventional "visual" scientific assessment, in order to determine the value of the predictions for operational use. For this study, the ionosphere at two ionosonde stations has been studied in depth, one each from the northern and southern mid-latitudes. The model clearly captures the seasonal dependence in the ionospheric response to geomagnetic activity at mid-latitude, reproducing the tendency for decreased ion density in the summer hemisphere and increased densities in winter. In contrast to the "visual" success of the model, the detailed quantitative comparisons, which are necessary for space weather applications, are less impressive. The accuracy, or value, of the model has been quantified by evaluating the daily standard deviation, the root-mean-square error, and the correlation coefficient between the data and model predictions. The modeled quiet-time variability, or standard

  6. What controls biological productivity in coastal upwelling systems? Insights from a comparative modeling study

    Science.gov (United States)

    Lachkar, Z.; Gruber, N.

    2011-06-01

    The magnitude of the biological productivity in Eastern Boundary Upwelling Systems (EBUS) is traditionally viewed as directly reflecting the upwelling intensity. Yet, different EBUS show different sensitivities of productivity to upwelling-favorable winds (Carr and Kearns, 2003). Here, using a comparative modeling study of the California Current System (California CS) and Canary Current System (Canary CS), we show how physical and environmental factors, such as light, temperature and cross-shore circulation modulate the response of biological productivity to upwelling strength. To this end, we made a series of eddy-resolving simulations of the California CS and Canary CS using the Regional Ocean Modeling System (ROMS), coupled to a nitrogen based Nutrient-Phytoplankton-Zooplankton-Detritus (NPZD) ecosystem model. We find the nutrient content of the euphotic zone to be 20 % smaller in the Canary CS relative to the California CS. Yet, the biological productivity is 50 % smaller in the latter. This is due to: (1) a faster nutrient-replete growth in the Canary CS relative to the California CS, related to a more favorable light and temperature conditions in the Canary CS, and (2) the longer nearshore water residence times in the Canary CS which lead to larger buildup of biomass in the upwelling zone, thereby enhancing the productivity. The longer residence times in the Canary CS appear to be associated with the wider continental shelves and the lower eddy activity characterizing this upwelling system. This results in a weaker offshore export of nutrients and organic matter, thereby increasing local nutrient recycling and enhancing the coupling between new and export production in the Northwest African system. Our results suggest that climate change induced perturbations such as upwelling favorable wind intensification might lead to contrasting biological responses in the California CS and the Canary CS, with major implications for the biogeochemical cycles and fisheries

  7. What controls biological productivity in coastal upwelling systems? Insights from a comparative modeling study

    Directory of Open Access Journals (Sweden)

    Z. Lachkar

    2011-06-01

    Full Text Available The magnitude of the biological productivity in Eastern Boundary Upwelling Systems (EBUS is traditionally viewed as directly reflecting the upwelling intensity. Yet, different EBUS show different sensitivities of productivity to upwelling-favorable winds (Carr and Kearns, 2003. Here, using a comparative modeling study of the California Current System (California CS and Canary Current System (Canary CS, we show how physical and environmental factors, such as light, temperature and cross-shore circulation modulate the response of biological productivity to upwelling strength. To this end, we made a series of eddy-resolving simulations of the California CS and Canary CS using the Regional Ocean Modeling System (ROMS, coupled to a nitrogen based Nutrient-Phytoplankton-Zooplankton-Detritus (NPZD ecosystem model. We find the nutrient content of the euphotic zone to be 20 % smaller in the Canary CS relative to the California CS. Yet, the biological productivity is 50 % smaller in the latter. This is due to: (1 a faster nutrient-replete growth in the Canary CS relative to the California CS, related to a more favorable light and temperature conditions in the Canary CS, and (2 the longer nearshore water residence times in the Canary CS which lead to larger buildup of biomass in the upwelling zone, thereby enhancing the productivity. The longer residence times in the Canary CS appear to be associated with the wider continental shelves and the lower eddy activity characterizing this upwelling system. This results in a weaker offshore export of nutrients and organic matter, thereby increasing local nutrient recycling and enhancing the coupling between new and export production in the Northwest African system. Our results suggest that climate change induced perturbations such as upwelling favorable wind intensification might lead to contrasting biological responses in the California CS and the Canary CS, with major implications for the biogeochemical cycles

  8. [Living environment and activation of early maladaptive schemas specific to the elderly: Comparative study among 80 individuals].

    Science.gov (United States)

    Obeid, S; Kazour, F; Kazour, G

    2015-06-01

    Early maladaptive schemas described by Young may be identified in the elderly. They represent models and themes of emotions, memories, thoughts and bodily sensations experienced by the individual. This study aims to evaluate the activation of early maladaptive thoughts in the elderly depending on their living environment. The Young Schema Questionnaire--short form--was administered to 80 elderly individuals (40 living in a nursing home, and 40 in their own home with at least one person). The studied schemas that were most relevant to the elderly were the maladaptive schemas of abandonment, emotional deprivation, mistrust, exclusion, dependency, vulnerability and emotional overcontrol. The Mini-Mental State Examination (MMSE) and the Geriatric Depression Scale were administered to eliminate dementia or depression among individuals. Individuals living in a nursing home, compared to their controls had increased activation of schemas of emotional deprivation (22.5% vs. 7.5%), abandonment (15% vs. 0%), mistrust (32.5% vs. 2.5%), exclusion (7.5% vs. 0%), and emotional overcontrol (25% vs. 2.5%). The activation of maladaptive schemas was significantly elevated in nursing homes for those 5 schemas, while there was no difference in activation between the 2 groups concerning the schemas of dependency and vulnerability. The activation of early maladaptive schemas of emotional deprivation, abandonment, mistrust, exclusion, and emotional overcontrol is higher in individuals living in nursing homes compared to a control group of individuals living in their homes with at least one companion. This schema activation may be related to a lack of emotional and family support in the elderly. Copyright © 2015 L’Encéphale, Paris. Published by Elsevier Masson SAS. All rights reserved.

  9. AeroCom INSITU Project: Comparing modeled and measured aerosol optical properties

    Science.gov (United States)

    Andrews, Elisabeth; Schmeisser, Lauren; Schulz, Michael; Fiebig, Markus; Ogren, John; Bian, Huisheng; Chin, Mian; Easter, Richard; Ghan, Steve; Kokkola, Harri; Laakso, Anton; Myhre, Gunnar; Randles, Cynthia; da Silva, Arlindo; Stier, Phillip; Skeie, Ragnehild; Takemura, Toshihiko; van Noije, Twan; Zhang, Kai

    2016-04-01

    AeroCom, an open international collaboration of scientists seeking to improve global aerosol models, recently initiated a project comparing model output to in-situ, surface-based measurements of aerosol optical properties. The model/measurement comparison project, called INSITU, aims to evaluate the performance of a suite of AeroCom aerosol models with site-specific observational data in order to inform iterative improvements to model aerosol modules. Surface in-situ data has the unique property of being traceable to physical standards, which is an asset in accomplishing the overall goal of bettering the accuracy of aerosols processes and the predicative capability of global climate models. Here we compare dry, in-situ aerosol scattering and absorption data from ~75 surface, in-situ sites from various global aerosol networks (including NOAA, EUSAAR/ACTRIS and GAW) with a simulated optical properties from a suite of models participating in the AeroCom project. We report how well models reproduce aerosol climatologies for a variety of time scales, aerosol characteristics and behaviors (e.g., aerosol persistence and the systematic relationships between aerosol optical properties), and aerosol trends. Though INSITU is a multi-year endeavor, preliminary phases of the analysis suggest substantial model biases in absorption and scattering coefficients compared to surface measurements, though the sign and magnitude of the bias varies with location. Spatial patterns in the biases highlight model weaknesses, e.g., the inability of models to properly simulate aerosol characteristics at sites with complex topography. Additionally, differences in modeled and measured systematic variability of aerosol optical properties suggest that some models are not accurately capturing specific aerosol behaviors, for example, the tendency of in-situ single scattering albedo to decrease with decreasing aerosol extinction coefficient. The endgoal of the INSITU project is to identify specific

  10. Aspartic acid aminotransferase activity is increased in actively spiking compared with non-spiking human epileptic cortex.

    Science.gov (United States)

    Kish, S J; Dixon, L M; Sherwin, A L

    1988-01-01

    Increased concentration of the excitatory neurotransmitter aspartic acid in actively spiking human epileptic cerebral cortex was recently described. In order to further characterise changes in the aspartergic system in epileptic brain, the behaviour of aspartic acid aminotransferase (AAT), a key enzyme involved in aspartic acid metabolism has now been examined. Electrocorticography performed during surgery was employed to identify cortical epileptic spike foci in 16 patients undergoing temporal lobectomy for intractable seizures. Patients with spontaneously spiking lateral temporal cortex (n = 8) were compared with a non-spiking control group (n = 8) of patients in whom the epileptic lesions were confined to the hippocampus sparing the temporal convexity. Mean activity of AAT in spiking cortex was significantly elevated by 16-18%, with aspartic acid concentration increased by 28%. Possible explanations for the enhanced AAT activity include increased proliferation of cortical AAT-containing astrocytes at the spiking focus and/or a generalised increase in neuronal or extraneuronal metabolism consequent to the ongoing epileptic discharge. It is suggested that the data provide additional support for a disturbance of central excitatory aspartic acid mechanisms in human epileptic brain. PMID:2898010

  11. Comparative study of active and inactive elderly persons through the assessment of activities of daily living and quality of life

    Directory of Open Access Journals (Sweden)

    S. Caporicci

    2011-01-01

    Full Text Available This study aimed at evaluating the activities of daily living and quality of active and inactive seniors’ life. This is a descriptive research of a quantitative nature. Participants were 24 seniors, 12 physical activity practitioners (PPA and 12 non-practitioners (NPPA. The instrument was a demographic questionnaire and SF-36 for measuring the quality of life and tests proposed by GDLAM. SPSS 15.0 was used for data analysis. The results obtained by the sociodemographic questionnaire for PPA and NPPA groups were, respectively: age − 69.5 and 70.0 years, marital status − 50.0% widower and 41.7% were married; education − 50.0% with complete elementary school and 58.3% with incomplete elementary school; health problems − 25.0% and 58.33% hypertension. In functional autonomy tests, the PPA group had shorter execution time when compared with the NPPA group; however, both groups found themselves in the rating of "weak" according to the protocol GDLAM. We concluded that there was no statistical difference between groups.

  12. HbIDI, SlIDI and EcIDI: A comparative study of isopentenyl diphosphate isomerase activity and structure.

    Science.gov (United States)

    Berthelot, Karine; Estevez, Yannick; Quiliano, Miguel; Baldera-Aguayo, Pedro A; Zimic, Mirko; Pribat, Anne; Bakleh, Marc-Elias; Teyssier, Emeline; Gallusci, Philippe; Gardrat, Christian; Lecomte, Sophie; Peruch, Frédéric

    2016-08-01

    In this study, we cloned, expressed and purified the isopentenyl diphosphate isomerases (IDIs) from two plants, Hevea brasiliensis and Solanum lycopersicum, and compared them to the already well characterized Escherichia coli IDI. Phylogenetic analysis showed high homology between the three enzymes. Their catalytic activity was investigated in vitro with recombinant purified enzymes and in vivo by complementation colorimetric tests. The three enzymes displayed consistent activities both in vitro and in vivo. In term of structure, studied by ATR-FTIR and molecular modeling, it is clear that both plant enzymes are more related to their human homologue than to E. coli IDI. But it is assumed that EcIDI represent the minimalistic part of the catalytic core, as both plant enzymes present a supplementary sequence forming an extra α-helice surrounding the catalytic site that could facilitate the biocatalysis. New potential biotechnological applications may be envisaged.

  13. Comparative experimental evaluation of the efficacy of Prostamol Uno and Samprost on rat model of chronic aseptic prostate inflammation.

    Science.gov (United States)

    Pahomova, A V; Borovskaja, T G; Fomina, T I; Ermolaeva, L A; Vychuzhanina, A V; Rumpel, O A; Granstrem, O K; Baranova, O V

    2011-11-01

    Comparative experimental evaluation of the efficiency of prostatotropic drugs Prostamol Uno and Samprost on the model of the chronic aseptic prostate inflammation in rats was performed. It was established that peptide drug Samprost decelerates sclerotic processes in the prostate gland to a greater extent than herbal preparation Prostamol Uno. Both products equally stimulate secretory activity of the gland. Prostamol Uno, unlike Samprost, prevents the development of reduced sexual motivation, one of the complications of chronic prostatitis.

  14. The utility of comparative models and the local model quality for protein crystal structure determination by Molecular Replacement

    Directory of Open Access Journals (Sweden)

    Pawlowski Marcin

    2012-11-01

    Full Text Available Abstract Background Computational models of protein structures were proved to be useful as search models in Molecular Replacement (MR, a common method to solve the phase problem faced by macromolecular crystallography. The success of MR depends on the accuracy of a search model. Unfortunately, this parameter remains unknown until the final structure of the target protein is determined. During the last few years, several Model Quality Assessment Programs (MQAPs that predict the local accuracy of theoretical models have been developed. In this article, we analyze whether the application of MQAPs improves the utility of theoretical models in MR. Results For our dataset of 615 search models, the real local accuracy of a model increases the MR success ratio by 101% compared to corresponding polyalanine templates. On the contrary, when local model quality is not utilized in MR, the computational models solved only 4.5% more MR searches than polyalanine templates. For the same dataset of the 615 models, a workflow combining MR with predicted local accuracy of a model found 45% more correct solution than polyalanine templates. To predict such accuracy MetaMQAPclust, a “clustering MQAP” was used. Conclusions Using comparative models only marginally increases the MR success ratio in comparison to polyalanine structures of templates. However, the situation changes dramatically once comparative models are used together with their predicted local accuracy. A new functionality was added to the GeneSilico Fold Prediction Metaserver in order to build models that are more useful for MR searches. Additionally, we have developed a simple method, AmIgoMR (Am I good for MR?, to predict if an MR search with a template-based model for a given template is likely to find the correct solution.

  15. Complex human activities recognition using interval temporal syntactic model

    Institute of Scientific and Technical Information of China (English)

    夏利民; 韩芬; 王军

    2016-01-01

    A novel method based on interval temporal syntactic model was proposed to recognize human activities in video flow. The method is composed of two parts: feature extract and activities recognition. Trajectory shape descriptor, speeded up robust features (SURF) and histograms of optical flow (HOF) were proposed to represent human activities, which provide more exhaustive information to describe human activities on shape, structure and motion. In the process of recognition, a probabilistic latent semantic analysis model (PLSA) was used to recognize sample activities at the first step. Then, an interval temporal syntactic model, which combines the syntactic model with the interval algebra to model the temporal dependencies of activities explicitly, was introduced to recognize the complex activities with a time relationship. Experiments results show the effectiveness of the proposed method in comparison with other state-of-the-art methods on the public databases for the recognition of complex activities.

  16. Comparative analysis of modified PMV models and SET models to predict human thermal sensation in naturally ventilated buildings

    DEFF Research Database (Denmark)

    Gao, Jie; Wang, Yi; Wargocki, Pawel

    2015-01-01

    In this paper, a comparative analysis was performed on the human thermal sensation estimated by modified predicted mean vote (PMV) models and modified standard effective temperature (SET) models in naturally ventilated buildings; the data were collected in field study. These prediction models were...... between the measured and predicted values using the modified PMV models exceeded 25%, while the difference between the measured thermal sensation and the predicted thermal sensation using modified SET models was approximately less than 25%. It is concluded that the modified SET models can predict human...... developed on the basis of the original PMV/SET models and consider the influence of occupants' expectations and human adaptive functions, including the extended PMV/SET models and the adaptive PMV/SET models. The results showed that when the indoor air velocity ranged from 0 to 0.2m/s and from 0.2 to 0.8m...

  17. A Comparative Study of Successful Central Nervous System Drugs Using Molecular Modeling

    Science.gov (United States)

    Kim, Hyosub; Sulaimon, Segun; Menezes, Sandra; Son, Anne; Menezes, Warren J. C.

    2011-01-01

    Molecular modeling is a powerful tool used for three-dimensional visualization and for exploring electrostatic forces involved in drug transport. This tool enhances student understanding of structure-property relationships, as well as actively engaging them in class. Molecular modeling of several central nervous system (CNS) drugs is used to…

  18. A Comparative Study of Successful Central Nervous System Drugs Using Molecular Modeling

    Science.gov (United States)

    Kim, Hyosub; Sulaimon, Segun; Menezes, Sandra; Son, Anne; Menezes, Warren J. C.

    2011-01-01

    Molecular modeling is a powerful tool used for three-dimensional visualization and for exploring electrostatic forces involved in drug transport. This tool enhances student understanding of structure-property relationships, as well as actively engaging them in class. Molecular modeling of several central nervous system (CNS) drugs is used to…

  19. A comparative study on immunomodulatory activity of polysaccharides from two official species of Ganoderma (Lingzhi).

    Science.gov (United States)

    Meng, Lan-Zhen; Xie, Jing; Lv, Guang-Ping; Hu, De-Jun; Zhao, Jing; Duan, Jin-Ao; Li, Shao-Ping

    2014-01-01

    Two Ganoderma species, G. lucidum and G. sinense, are listed as Lingzhi in Chinese Pharmacopoeia and they are considered to have the same therapeutic effects. Polysaccharides were the main immunomodulatory and anticancer components in Ganoderma. In this study, the chemical characters and the effects of polysaccharides from G. lucidum (GLPS) and G. sinense (GSPS) on macrophage functions were investigated and compared. Chemical studies showed that GLPS and GSPS were different, displaying various molecular weight distribution and ratio of monosaccharide components. In vitro pharmacological studies showed that both GLPS and GSPS had potent effects on macrophage functions, such as promoting macrophage phagocytosis, increasing their release of nitric oxide and cytokines interleukin (IL)-1α, IL-6, IL-10, and tumor necrosis factor-α. Generally, GLPS was more powerful than GSPS. This study is helpful to elucidate the active components and pharmacological variation between the 2 Ganoderma species. The structure-activity relationship of polysaccharides from Ganoderma needs further study.

  20. Comparative inhibition of tetrameric carbonyl reductase activity in pig heart cytosol by alkyl 4-pyridyl ketones.

    Science.gov (United States)

    Shimada, Hideaki; Tanigawa, Takahiro; Matayoshi, Kazunori; Katakura, Kazufumi; Babazono, Ken; Takayama, Hiroyuki; Murahashi, Tsuyoshi; Akita, Hiroyuki; Higuchi, Toshiyuki; Eto, Masashi; Imamura, Yorishige

    2014-06-01

    The present study is to elucidate the comparative inhibition of tetrameric carbonyl reductase (TCBR) activity by alkyl 4-pyridyl ketones, and to characterize its substrate-binding domain. The inhibitory effects of alkyl 4-pyridyl ketones on the stereoselective reduction of 4-benzoylpyridine (4-BP) catalyzed by TCBR were examined in the cytosolic fraction of pig heart. Of alkyl 4-pyridyl ketones, 4-hexanoylpyridine, which has a straight-chain alkyl group of five carbon atoms, inhibited most potently TCBR activity and was a competitive inhibitor. Furthermore, cyclohexyl pentyl ketone, which is substituted by cyclohexyl group instead of phenyl group of hexanophenone, had much lower ability to be reduced than hexanophenone. These results suggest that in addition to a hydrophobic cleft corresponding to a straight-chain alkyl group of five carbon atoms, a hydrophobic pocket with affinity for an aromatic group is located in the substrate-binding domain of TCBR.

  1. Comparative Study on Schizontocidal Activity of Recrystallized or Crude Daphnetin Against Malaria Parasites

    Institute of Scientific and Technical Information of China (English)

    QIN-MEI WANG; YI-CHANG NI; JIAN GUO; JIA-TONG WU; YING-JUN QIAN

    2004-01-01

    To compare the schizontocidal activity of recrystallized or crude daphnetin against malaria parasites in vivo. Methods Schizontocidal activity of recrystallized or crude daphnetin at various dosages was assessed in mice infected with Plasmodium berghei ANKA using a "4-day suppress assay". Results The comparison of the reduction rate of parasitemia caused by either recrystallized or crude dephnetin showed that ED50 of crude daphnetin was 18.36 mg/kg, with 95% confidence limit of 5.96-56.54 mg/kg while ED50 of recrystallized daphnetin was 11.46 mg/kg, with 95% confidence limit of 8.63-15.22 mg/kg. Conclution The results indicate that the efficacy of recrystallized daphnetin is 37.6% higher than that of crude daphnetin.

  2. Novel Control Strategy for VSI and CSI Active Filters and Comparing These Two Types of Filters

    Directory of Open Access Journals (Sweden)

    Gholam Reza Arab

    2014-10-01

    Full Text Available Recently to eliminate the harmonics and improve the power factor of the power networks, much attention has been attracted to active filters. The advantages of these filters are lower volume and their better compensating characteristics than the passive filters. In conventional sliding mode controllers, the source current waveform is fluctuated in near to zero values. In this paper, using a new sliding technique, lower Total Harmonic Distortion (THD in source current is obtained and the current waveform is improved. As well as, two novel control strategies for two types of active filters, VSI and CSI is proposed and then these two types of filters are compared to reduce THD value of source current.The proposed controlled strategies are simulated by MATLAB/Simulink. The Simulation results confirm that the proposed strategies reduce the THD of source current more than other strategies, and active filter based on CSI has a better performance than active filter based on VSI with a dead time area (for avoiding short circuit of the source in high powers.

  3. Comparative study on the antioxidant and anti-Toxoplasma activities of vanillin and its resorcinarene derivative.

    Science.gov (United States)

    Oliveira, Claudio B S; Meurer, Ywlliane S R; Oliveira, Marianne G; Medeiros, Wendy M T Q; Silva, Francisco O N; Brito, Ana C F; Pontes, Daniel de L; Andrade-Neto, Valter F

    2014-05-07

    A resorcinarene derivative of vanillin, resvan, was synthesized and characterized by spectroscopic techniques. We measured the cytotoxicity (in vivo and in vitro), antioxidant and anti-Toxoplasma activities of vanillin and the resorcinarene compound. Here we show that vanillin has a dose-dependent behavior with IC50 of 645 µg/mL through an in vitro cytotoxicity assay. However, we could not observe any cytotoxic response at higher concentrations of resvan (IC50 > 2,000 µg/mL). The in vivo acute toxicity assays of vanillin and resvan exhibited a significant safety margin indicated by a lack of systemic and behavioral toxicity up to 300 mg/kg during the first 30 min, 24 h or 14 days after administration. The obtained derivative showed greater antioxidative activity (84.9%) when comparing to vanillin (19.4%) at 1,000 μg/mL. In addition, vanillin presents anti-Toxoplasma activity, while resvan does not show that feature. Our findings suggest that this particular derivative has an efficient antioxidant activity and a negligible cytotoxic effect, making it a potential target for further biological investigations.

  4. Active learning on the ward: outcomes from a comparative trial with traditional methods.

    Science.gov (United States)

    Melo Prado, Hegla; Hannois Falbo, Gilliatt; Rodrigues Falbo, Ana; Natal Figueirôa, José

    2011-03-01

    Academic activity during internship is essentially practical and ward rounds are traditionally considered the cornerstone of clinical education. However, the efficacy and effectiveness of ward rounds for learning purposes have been under-investigated and it is necessary to assess alternative educational paradigms for this activity. This study aimed to compare the educational effectiveness of ward rounds conducted with two different learning methodologies. Student subjects were first tested on 30 true/false questions to assess their initial degree of knowledge on pneumonia and diarrhoea. Afterwards, they attended ward rounds conducted using an active and a traditional learning methodology. The participants were submitted to a second test 48hours later in order to assess knowledge acquisition and were asked to answer two questions about self-directed learning and their opinions on the two learning methodologies used. Seventy-two medical students taking part in a paediatric clinic rotation were enrolled. The active methodology proved to be more effective than the traditional methodology for the three outcomes considered: knowledge acquisition (33 students [45.8%] versus 21 students [29.2%]; p=0.03); self-directed learning (38 students [52.8%] versus 11 students [15.3%]; pactive methodology produced better results than the traditional methodology in a ward-based context. This study seems to be valuable in terms of the new evidence it demonstrates on learning methodologies in the context of the ward round. © Blackwell Publishing Ltd 2011.

  5. COMPARATIVE SUDY OF THE ELECTROENCEPHALOGRAPHIC ACTIVITY AT PROFESSIONAL HANDBALL AND FENCERS PLAYERS

    Directory of Open Access Journals (Sweden)

    DENISA ENESCU BIERU

    2010-12-01

    Full Text Available Purpose. Our purpose was to study the electroencephalographic activity of professional handball and fencers players, to compare the obtained data and to identify a possible neurophysiologic pattern associate to practiced sportive activity. Material and method. The study was performed on a group of 22 male athletes, 11 handball players and 11 fencers (different stress degrees of the upper members, active for between 5 and 12 years exclusively in eitherhandball or fencing. Using Nihon-Kohden EEG-9200 device, was recorded EEG line during some activities (relaxation-contraction,which can emphasize possible characteristic cerebral patterns, EEG analyze was made by assessing the classic rhythms and synthetic indexes as edge frequency. To perform spectral analyze was used fast Fourier transformation and for wave values comparison was used Pearson correlation coefficient. Results. For both groups was remarked a slight increase of the theta wave values and for handball players a high degree of correlation for theta and beta indexes and also a correlation in the dominant hemisphere for alpha1 and 2.Conclusions. EEG complex testing of professional sportsmen, as well as the outlining of an EEG pattern specific to studied sportive discipline, represent an original aspect of this study

  6. Activated sludge model No. 2d, ASM2d

    DEFF Research Database (Denmark)

    Henze, M.

    1999-01-01

    The Activated Sludge Model No. 2d (ASM2d) presents a model for biological phosphorus removal with simultaneous nitrification-denitrification in activated sludge systems. ASM2d is based on ASM2 and is expanded to include the denitrifying activity of the phosphorus accumulating organisms (PAOs...

  7. Comparing habitat suitability and connectivity modeling methods for conserving pronghorn migrations.

    Directory of Open Access Journals (Sweden)

    Erin E Poor

    Full Text Available Terrestrial long-distance migrations are declining globally: in North America, nearly 75% have been lost. Yet there has been limited research comparing habitat suitability and connectivity models to identify migration corridors across increasingly fragmented landscapes. Here we use pronghorn (Antilocapra americana migrations in prairie habitat to compare two types of models that identify habitat suitability: maximum entropy (Maxent and expert-based (Analytic Hierarchy Process. We used distance to wells, distance to water, NDVI, land cover, distance to roads, terrain shape and fence presence to parameterize the models. We then used the output of these models as cost surfaces to compare two common connectivity models, least-cost modeling (LCM and circuit theory. Using pronghorn movement data from spring and fall migrations, we identified potential migration corridors by combining each habitat suitability model with each connectivity model. The best performing model combination was Maxent with LCM corridors across both seasons. Maxent out-performed expert-based habitat suitability models for both spring and fall migrations. However, expert-based corridors can perform relatively well and are a cost-effective alternative if species location data are unavailable. Corridors created using LCM out-performed circuit theory, as measured by the number of pronghorn GPS locations present within the corridors. We suggest the use of a tiered approach using different corridor widths for prioritizing conservation and mitigation actions, such as fence removal or conservation easements.

  8. Modeling discourse management compared to other classroom management styles in university physics

    Science.gov (United States)

    Desbien, Dwain Michael

    2002-01-01

    A classroom management technique called modeling discourse management was developed to enhance the modeling theory of physics. Modeling discourse management is a student-centered management that focuses on the epistemology of science. Modeling discourse is social constructivist in nature and was designed to encourage students to present classroom material to each other. In modeling discourse management, the instructor's primary role is of questioner rather than provider of knowledge. Literature is presented that helps validate the components of modeling discourse. Modeling discourse management was compared to other classroom management styles using multiple measures. Both regular and honors university physics classes were investigated. This style of management was found to enhance student understanding of forces, problem-solving skills, and student views of science compared to traditional classroom management styles for both honors and regular students. Compared to other reformed physics classrooms, modeling discourse classes performed as well or better on student understanding of forces. Outside evaluators viewed modeling discourse classes to be reformed, and it was determined that modeling discourse could be effectively disseminated.

  9. Comparing Habitat Suitability and Connectivity Modeling Methods for Conserving Pronghorn Migrations

    Science.gov (United States)

    Poor, Erin E.; Loucks, Colby; Jakes, Andrew; Urban, Dean L.

    2012-01-01

    Terrestrial long-distance migrations are declining globally: in North America, nearly 75% have been lost. Yet there has been limited research comparing habitat suitability and connectivity models to identify migration corridors across increasingly fragmented landscapes. Here we use pronghorn (Antilocapra americana) migrations in prairie habitat to compare two types of models that identify habitat suitability: maximum entropy (Maxent) and expert-based (Analytic Hierarchy Process). We used distance to wells, distance to water, NDVI, land cover, distance to roads, terrain shape and fence presence to parameterize the models. We then used the output of these models as cost surfaces to compare two common connectivity models, least-cost modeling (LCM) and circuit theory. Using pronghorn movement data from spring and fall migrations, we identified potential migration corridors by combining each habitat suitability model with each connectivity model. The best performing model combination was Maxent with LCM corridors across both seasons. Maxent out-performed expert-based habitat suitability models for both spring and fall migrations. However, expert-based corridors can perform relatively well and are a cost-effective alternative if species location data are unavailable. Corridors created using LCM out-performed circuit theory, as measured by the number of pronghorn GPS locations present within the corridors. We suggest the use of a tiered approach using different corridor widths for prioritizing conservation and mitigation actions, such as fence removal or conservation easements. PMID:23166656

  10. The use of discrete-event simulation modeling to compare handwritten and electronic prescribing systems.

    Science.gov (United States)

    Ghany, Ahmad; Vassanji, Karim; Kuziemsky, Craig; Keshavjee, Karim

    2013-01-01

    Electronic prescribing (e-prescribing) is expected to bring many benefits to Canadian healthcare, such as a reduction in errors and adverse drug reactions. As there currently is no functioning e-prescribing system in Canada that is completely electronic, we are unable to evaluate the performance of a live system. An alternative approach is to use simulation modeling for evaluation. We developed two discrete-event simulation models, one of the current handwritten prescribing system and one of a proposed e-prescribing system, to compare the performance of these two systems. We were able to compare the number of processes in each model, workflow efficiency, and the distribution of patients or prescriptions. Although we were able to compare these models to each other, using discrete-event simulation software was challenging. We were limited in the number of variables we could measure. We discovered non-linear processes and feedback loops in both models that could not be adequately represented using discrete-event simulation software. Finally, interactions between entities in both models could not be modeled using this type of software. We have come to the conclusion that a more appropriate approach to modeling both the handwritten and electronic prescribing systems would be to use a complex adaptive systems approach using agent-based modeling or systems-based modeling.

  11. Modeling crustal deformation near active faults and volcanic centers: a catalog of deformation models and modeling approaches

    Science.gov (United States)

    Battaglia, Maurizio; ,; Peter, F.; Murray, Jessica R.

    2013-01-01

    This manual provides the physical and mathematical concepts for selected models used to interpret deformation measurements near active faults and volcanic centers. The emphasis is on analytical models of deformation that can be compared with data from the Global Positioning System (GPS) receivers, Interferometric synthetic aperture radar (InSAR), leveling surveys, tiltmeters and strainmeters. Source models include pressurized spherical, ellipsoidal, and horizontal penny-shaped geometries in an elastic, homogeneous, flat half-space. Vertical dikes and faults are described following the mathematical notation for rectangular dislocations in an elastic, homogeneous, flat half-space. All the analytical expressions were verified against numerical models developed by use of COMSOL Multyphics, a Finite Element Analysis software (http://www.comsol.com). In this way, typographical errors present were identified and corrected. Matlab scripts are also provided to facilitate the application of these models.

  12. Comparative Analysis of Immune Cells Activation and Cytotoxicity upon Exposure Pathogen and Glycoconjugates

    Science.gov (United States)

    Saheb, Entsar; Tarasenko, Olga

    2010-04-01

    Peripheral mononuclear cells (PMNC) including macrophages are key players in the immune responses against pathogens. Any infection could be attenuated if PMNC would be activated and capable to kill pathogen on exposure. It was shown that glycoconjugates (GCs) play an important role in adhesion to, activation, and recognition of pathogens. Nitric oxide (NO) is a regulatory molecule released by immune cells against pathogens that include bacteria, protozoa, helminthes, and fungi. NO is a highly reactive and diffusible molecule that controls replication or intracellular killing of pathogens during infection and immune responses against infections caused by pathogens. Avirulent Bacillus anthracis Sterne spores were used as a model in our study. The purpose of this study was two-fold: A) to analyze PMNC activation through NO production and B) to determine the cytotoxicity effect based on lactate dehydrogenase (LDH) upon exposure to pathogen exerted by GCs. The latter were used "prior to," "during," and "following" PMNC exposure to pathogen in order to modulate immune responses to spores during phagocytosis. Post-phagocytosis study involved the assessment of NO and LDH release by macrophages upon exposure to spores. Results have shown that untreated PMNC released low levels of NO. However, in the presence of GCs, PMNC were activated and produced high levels of NO under all experimental conditions. In addition, the results showed that GC1, GC3 are capable of increasing PMNC activity as evidenced by higher NO levels under the "prior," "during" and "following" to pathogen exposure conditions. On the other hand, GCs were capable of controlling cytotoxicity and decreased LDH levels during phagocytosis of spores. Our findings suggest that GCs stimulate NO production by activating PMNC and decrease cytotoxicity caused by pathogens on PMNC.

  13. Regional disaster impact analysis: comparing input-output and computable general equilibrium models

    Science.gov (United States)

    Koks, Elco E.; Carrera, Lorenzo; Jonkeren, Olaf; Aerts, Jeroen C. J. H.; Husby, Trond G.; Thissen, Mark; Standardi, Gabriele; Mysiak, Jaroslav

    2016-08-01

    A variety of models have been applied to assess the economic losses of disasters, of which the most common ones are input-output (IO) and computable general equilibrium (CGE) models. In addition, an increasing number of scholars have developed hybrid approaches: one that combines both or either of them in combination with noneconomic methods. While both IO and CGE models are widely used, they are mainly compared on theoretical grounds. Few studies have compared disaster impacts of different model types in a systematic way and for the same geographical area, using similar input data. Such a comparison is valuable from both a scientific and policy perspective as the magnitude and the spatial distribution of the estimated losses are born likely to vary with the chosen modelling approach (IO, CGE, or hybrid). Hence, regional disaster impact loss estimates resulting from a range of models facilitate better decisions and policy making. Therefore, this study analyses the economic consequences for a specific case study, using three regional disaster impact models: two hybrid IO models and a CGE model. The case study concerns two flood scenarios in the Po River basin in Italy. Modelling results indicate that the difference in estimated total (national) economic losses and the regional distribution of those losses may vary by up to a factor of 7 between the three models, depending on the type of recovery path. Total economic impact, comprising all Italian regions, is negative in all models though.

  14. Modeling organic nitrogen conversions in activated sludge bioreactors.

    Science.gov (United States)

    Makinia, Jacek; Pagilla, Krishna; Czerwionka, Krzysztof; Stensel, H David

    2011-01-01

    For biological nutrient removal (BNR) systems designed to maximize nitrogen removal, the effluent total nitrogen (TN) concentration may range from 2.0 to 4.0 g N/m(3) with about 25-50% in the form of organic nitrogen (ON). In this study, current approaches to modeling organic N conversions (separate processes vs. constant contents of organic fractions) were compared. A new conceptual model of ON conversions was developed and combined with Activated Sludge Model No. 2d (ASM2d). The model addresses a new insight into the processes of ammonification, biomass decay and hydrolysis of particulate and colloidal ON (PON and CON, respectively). Three major ON fractions incorporated are defined as dissolved (DON) (model parameter set, the behaviors of both inorganic N forms (NH4-N, NOX-N) and ON forms (DON, CON) in the batch experiments were predicted. The challenges to accurately simulate and predict effluent ON levels from BNR systems are due to analytical methods of direct ON measurement (replacing TKN) and lack of large enough database (in-process measurements, dynamic variations of the ON concentrations) which can be used to determine parameter value ranges.

  15. Model predictions of metal speciation in freshwaters compared to measurements by in situ techniques.

    NARCIS (Netherlands)

    Unsworth, Emily R; Warnken, Kent W; Zhang, Hao; Davison, William; Black, Frank; Buffle, Jacques; Cao, Jun; Cleven, Rob; Galceran, Josep; Gunkel, Peggy; Kalis, Erwin; Kistler, David; Leeuwen, Herman P van; Martin, Michel; Noël, Stéphane; Nur, Yusuf; Odzak, Niksa; Puy, Jaume; Riemsdijk, Willem van; Sigg, Laura; Temminghoff, Erwin; Tercier-Waeber, Mary-Lou; Toepperwien, Stefanie; Town, Raewyn M; Weng, Liping; Xue, Hanbin

    2006-01-01

    Measurements of trace metal species in situ in a softwater river, a hardwater lake, and a hardwater stream were compared to the equilibrium distribution of species calculated using two models, WHAM 6, incorporating humic ion binding model VI and visual MINTEQ incorporating NICA-Donnan. Diffusive gra

  16. On Applications of Rasch Models in International Comparative Large-Scale Assessments: A Historical Review

    Science.gov (United States)

    Wendt, Heike; Bos, Wilfried; Goy, Martin

    2011-01-01

    Several current international comparative large-scale assessments of educational achievement (ICLSA) make use of "Rasch models", to address functions essential for valid cross-cultural comparisons. From a historical perspective, ICLSA and Georg Rasch's "models for measurement" emerged at about the same time, half a century ago. However, the…

  17. A comparative study between EGB gravity and GTR by modelling compact stars

    CERN Document Server

    Bhar, Piyali; Sharma, Ranjan

    2016-01-01

    In this paper we utilise the Krori-Barua ansatz to model compact stars within the framework of Einstein- Gauss-Bonnet (EGB) gravity. The thrust of our investigation is to carry out a comparative analysis of the physical properties of our models in EGB and classical general relativity theory.

  18. A comparative study between EGB gravity and GTR by modeling compact stars

    Energy Technology Data Exchange (ETDEWEB)

    Bhar, Piyali [Government General Degree College, Department of Mathematics, Hooghly, West Bengal (India); Govender, Megan [Durban University of Technology, Department of Mathematics, Faculty of Applied Sciences, Durban (South Africa); Sharma, Ranjan [P. D. Women' s College, Department of Physics, Jalpaiguri (India)

    2017-02-15

    In this paper we utilise the Krori-Barua ansatz to model compact stars within the framework of Einstein-Gauss-Bonnet (EGB) gravity. The thrust of our investigation is to carry out a comparative analysis of the physical properties of our models in EGB and classical general relativity theory with the help of graphical representation. From our analysis we have shown that the central density and central pressure of EGB star model is higher than the GTR star model. The most notable feature is that for both GTR and the EGB star model the compactness factor crosses the Buchdahl (Phys Rev 116:1027, 1959) limit. (orig.)

  19. Aligning Learning Activities with Instructional Models

    Science.gov (United States)

    Gurvitch, Rachel; Metzler, Michael

    2013-01-01

    Model-based instruction has been increasingly used in physical education for the past two decades. Metzler (2011) identified eight instructional models that are commonly used in physical education today. Each model is designed to promote certain kinds of learning outcomes for students and to address different combinations of the national…

  20. Active orientation models for face alignment in-the-wild

    NARCIS (Netherlands)

    Tzimiropoulos, Georgios; Alabort-i-Medina, Joan; Zafeiriou, Stefanos; Pantic, Maja

    2014-01-01

    We present Active Orientation Models (AOMs), generative models of facial shape and appearance, which extend the well-known paradigm of Active Appearance Models (AAMs) for the case of generic face alignment under unconstrained conditions. Robustness stems from the fact that the proposed AOMs employ a

  1. "Active" and "Passive" Lava Resurfacing Processes on Io: A Comparative Study of Loki Patera and Prometheus

    Science.gov (United States)

    Davies, A. G.; Matson, D. L.; Leone, G.; Wilson, L.; Keszthelyi, L. P.

    2004-01-01

    Studies of Galileo Near Infrared Mapping Spectrometer (NIMS) data and ground based data of volcanism at Prometheus and Loki Patera on Io reveal very different mechanisms of lava emplacement at these two volcanoes. Data analyses show that the periodic nature of Loki Patera s volcanism from 1990 to 2001 is strong evidence that Loki s resurfacing over this period resulted from the foundering of a crust on a lava lake. This process is designated passive , as there is no reliance on sub-surface processes: the foundering of the crust is inevitable. Prometheus, on the other hand, displays an episodicity in its activity which we designate active . Like Kilauea, a close analog, Prometheus s effusive volcanism is dominated by pulses of magma through the nearsurface plumbing system. Each system affords views of lava resurfacing processes through modelling.

  2. The Consensus String Problem and the Complexity of Comparing Hidden Markov Models

    DEFF Research Database (Denmark)

    Lyngsø, Rune Bang; Pedersen, Christian Nørgaard Storm

    2002-01-01

    The basic theory of hidden Markov models was developed and applied to problems in speech recognition in the late 1960s, and has since then been applied to numerous problems, e.g. biological sequence analysis. Most applications of hidden Markov models are based on efficient algorithms for computing...... the probability of generating a given string, or computing the most likely path generating a given string. In this paper we consider the problem of computing the most likely string, or consensus string, generated by a given model, and its implications on the complexity of comparing hidden Markov models. We show...... that computing the consensus string, and approximating its probability within any constant factor, is NP-hard, and that the same holds for the closely related labeling problem for class hidden Markov models. Furthermore, we establish the NP-hardness of comparing two hidden Markov models under the L∞- and L1...

  3. The Consensus String Problem and the Complexity of Comparing Hidden Markov Models

    DEFF Research Database (Denmark)

    Lyngsø, Rune Bang; Pedersen, Christian Nørgaard Storm

    2002-01-01

    The basic theory of hidden Markov models was developed and applied to problems in speech recognition in the late 1960s, and has since then been applied to numerous problems, e.g. biological sequence analysis. Most applications of hidden Markov models are based on efficient algorithms for computing...... the probability of generating a given string, or computing the most likely path generating a given string. In this paper we consider the problem of computing the most likely string, or consensus string, generated by a given model, and its implications on the complexity of comparing hidden Markov models. We show...... that computing the consensus string, and approximating its probability within any constant factor, is NP-hard, and that the same holds for the closely related labeling problem for class hidden Markov models. Furthermore, we establish the NP-hardness of comparing two hidden Markov models under the L∞- and L1...

  4. Comparative study on different models for estimation of direct normal irradiance (DNI) over Egypt atmosphere

    Energy Technology Data Exchange (ETDEWEB)

    Madkour, M.A.; Hamed, A.B. [Physics Department, Faculty of Science, Mansoura University (Egypt); El-Metwally, M. [Physics Department, Faculty of Education at Suez, Suez Canal University, Suez (Egypt)

    2006-03-01

    The results obtained by using seven-parameterization broadband models to estimate Direct Normal Irradiance (DNI) along with two spectral models for four sites in Egypt atmosphere were compared with ground DNI measurements. Some statistical indicators (MBE, RMSE and R{sup 2}) have been used to measure the performance of the used models. MBE for all dataset is <1% to both spectral models (SPCTRAL2, SMARTS2) and broadband models (MLWT1, MLWT2 and REST) while is equal to 1.2% to YANG model. However, RMSE are around 2% for spectral models and 3% to the broadband models. The error in prediction of DNI to such models is below experimental errors a part from the big number of observations. On the other hand, Louche, Dogniaux and Rodgers models provide relatively bad performance, RMSE are at most cases >4%. Determination coefficient (R{sup 2}) results to all models are near 1.0. If we excluded spectral models, the broadband models MLWT1, MLWT2 and REST along with YANG models provide the best performance in all tests, therefore, those models can be used in Egypt atmosphere. (author)

  5. Quantification of the accuracy of MRI generated 3D models of long bones compared to CT generated 3D models.

    Science.gov (United States)

    Rathnayaka, Kanchana; Momot, Konstantin I; Noser, Hansrudi; Volp, Andrew; Schuetz, Michael A; Sahama, Tony; Schmutz, Beat

    2012-04-01

    Orthopaedic fracture fixation implants are increasingly being designed using accurate 3D models of long bones based on computer tomography (CT). Unlike CT, magnetic resonance imaging (MRI) does not involve ionising radiation and is therefore a desirable alternative to CT. This study aims to quantify the accuracy of MRI-based 3D models compared to CT-based 3D models of long bones. The femora of five intact cadaver ovine limbs were scanned using a 1.5 T MRI and a CT scanner. Image segmentation of CT and MRI data was performed using a multi-threshold segmentation method. Reference models were generated by digitising the bone surfaces free of soft tissue with a mechanical contact scanner. The MRI- and CT-derived models were validated against the reference models. The results demonstrated that the CT-based models contained an average error of 0.15 mm while the MRI-based models contained an average error of 0.23 mm. Statistical validation shows that there are no significant differences between 3D models based on CT and MRI data. These results indicate that the geometric accuracy of MRI based 3D models was comparable to that of CT-based models and therefore MRI is a potential alternative to CT for generation of 3D models with high geometric accuracy.

  6. A comparative study of the modeled effects of atrazine on aquatic plant communities in midwestern streams.

    Science.gov (United States)

    Nair, Shyam K; Bartell, Steven M; Brain, Richard A

    2015-11-01

    Potential effects of atrazine on the nontarget aquatic plants characteristic of lower-order streams in the Midwestern United States were previously assessed using the Comprehensive Aquatic System Model (CASMATZ ). Another similar bioenergetics-based, mechanistic model, AQUATOX, was examined in the present study, with 3 objectives: 1) to develop an AQUATOX model simulation similar to the CASMATZ model reference simulation in describing temporal patterns of biomass production by modeled plant populations, 2) to examine the implications of the different approaches used by the models in deriving plant community-based levels of concern (LOCs) for atrazine, and 3) to determine the feasibility of implementing alternative ecological models to assess ecological impacts of atrazine on lower-order Midwestern streams. The results of the present comparative modeling study demonstrated that a similar reference simulation to that from the CASMATZ model could be developed using the AQUATOX model. It was also determined that development of LOCs and identification of streams with exposures in excess of the LOCs were feasible with the AQUATOX model. Compared with the CASMATZ model results, however, the AQUATOX model consistently produced higher estimates of LOCs and generated non-monotonic variations of atrazine effects with increasing exposures. The results of the present study suggest an opportunity for harmonizing the treatments of toxicity and toxicity parameter estimation in the CASMATZ and the AQUATOX models. Both models appear useful in characterizing the potential impacts of atrazine on nontarget aquatic plant populations in lower-order Midwestern streams. The present model comparison also suggests that, with appropriate parameterization, these process-based models can be used to assess the potential effects of other xenobiotics on stream ecosystems.

  7. What can be learned from computer modeling? Comparing expository and modeling approaches to teaching dynamic systems behavior

    NARCIS (Netherlands)

    van Borkulo, S.P.|info:eu-repo/dai/nl/297554727; van Joolingen, W.R.; Savelsbergh, E.R.|info:eu-repo/dai/nl/17345853X; de Jong, T.

    2012-01-01

    Computer modeling has been widely promoted as a means to attain higher order learning outcomes. Substantiating these benefits, however, has been problematic due to a lack of proper assessment tools. In this study, we compared computer modeling with expository instruction, using a tailored assessment

  8. Comparing Video Modeling and Graduated Guidance Together and Video Modeling Alone for Teaching Role Playing Skills to Children with Autism

    Science.gov (United States)

    Akmanoglu, Nurgul; Yanardag, Mehmet; Batu, E. Sema

    2014-01-01

    Teaching play skills is important for children with autism. The purpose of the present study was to compare effectiveness and efficiency of providing video modeling and graduated guidance together and video modeling alone for teaching role playing skills to children with autism. The study was conducted with four students. The study was conducted…

  9. What can be learned from computer modeling? Comparing expository and modeling approaches to teaching dynamic systems behavior

    NARCIS (Netherlands)

    van Borkulo, S.P.; van Joolingen, W.R.; Savelsbergh, E.R.; de Jong, T.

    2012-01-01

    Computer modeling has been widely promoted as a means to attain higher order learning outcomes. Substantiating these benefits, however, has been problematic due to a lack of proper assessment tools. In this study, we compared computer modeling with expository instruction, using a tailored assessment

  10. Epidemiological models to support animal disease surveillance activities

    DEFF Research Database (Denmark)

    Willeberg, Preben; Paisley, Larry; Lind, Peter

    2011-01-01

    Epidemiological models have been used extensively as a tool in improving animal disease surveillance activities. A review of published papers identified three main groups of model applications: models for planning surveillance, models for evaluating the performance of surveillance systems...... and models for interpreting surveillance data as part of ongoing control or eradication programmes. Two Danish examples are outlined. The first illustrates how models were used in documenting country freedom from disease (trichinellosis) and the second demonstrates how models were of assistance in predicting...

  11. Explaining Japan's Innovation and Trade: A Model of Quality Competition and Dynamic Comparative Advantage

    OpenAIRE

    Grossman, Gene M.

    1990-01-01

    In this paper, I develop a model of dynamic comparative advantage based on endogenous innovation. Firms devote resources to R&D in order to improve the quality of high-technology products. Research successes generate profit opportunities in the world market. The model predicts that a country such as Japan, with an abundance of skilled labor and scarcity of natural resources, will specialize relatively in industrial innovation and in the production of high-technology goods. I use the model to ...

  12. Comparative Analysis of Smart Meters Deployment Business Models on the Example of the Russian Federation Markets

    Directory of Open Access Journals (Sweden)

    Daminov Ildar

    2016-01-01

    Full Text Available This paper presents the comparison of smart meter deployment business models to determine the most suitable option providing smart meters deployment. Authors consider 3 main business model of companies: distribution grid company, energy supplier (energosbyt and metering company. The goal of the article is to compare the business models of power companies from massive smart metering roll out in power system of Russian Federation.

  13. Comparative epigenomics in distantly related teleost species identifies conserved cis-regulatory nodes active during the vertebrate phylotypic period

    Science.gov (United States)

    Tena, Juan J.; González-Aguilera, Cristina; Fernández-Miñán, Ana; Vázquez-Marín, Javier; Parra-Acero, Helena; Cross, Joe W.; Rigby, Peter W.J.; Carvajal, Jaime J.; Wittbrodt, Joachim; Gómez-Skarmeta, José L.; Martínez-Morales, Juan R.

    2014-01-01

    The complex relationship between ontogeny and phylogeny has been the subject of attention and controversy since von Baer’s formulations in the 19th century. The classic concept that embryogenesis progresses from clade general features to species-specific characters has often been revisited. It has become accepted that embryos from a clade show maximum morphological similarity at the so-called phylotypic period (i.e., during mid-embryogenesis). According to the hourglass model, body plan conservation would depend on constrained molecular mechanisms operating at this period. More recently, comparative transcriptomic analyses have provided conclusive evidence that such molecular constraints exist. Examining cis-regulatory architecture during the phylotypic period is essential to understand the evolutionary source of body plan stability. Here we compare transcriptomes and key epigenetic marks (H3K4me3 and H3K27ac) from medaka (Oryzias latipes) and zebrafish (Danio rerio), two distantly related teleosts separated by an evolutionary distance of 115–200 Myr. We show that comparison of transcriptome profiles correlates with anatomical similarities and heterochronies observed at the phylotypic stage. Through comparative epigenomics, we uncover a pool of conserved regulatory regions (≈700), which are active during the vertebrate phylotypic period in both species. Moreover, we show that their neighboring genes encode mainly transcription factors with fundamental roles in tissue specification. We postulate that these regulatory regions, active in both teleost genomes, represent key constrained nodes of the gene networks that sustain the vertebrate body plan. PMID:24709821

  14. A Comparative Analysis of the New Five-Pole and Three-Pole Active Magnet Bearing

    Directory of Open Access Journals (Sweden)

    Pedram Vakili

    2012-07-01

    Full Text Available In recent years, more attention has been given to the active AMBs thanks to their low maintenance cost, suitability for clean environments, and high speed. One of the popular types of AMBs is the three-pole type with integrated and separate cores. Some deficiencies of this type of bearing are its high oscillation, low stability and low efficiency. This paper seeks to analyse the three-pole AMBs and describe their deficiencies and introduce and analyse a new five-pole AMB. The model thus proposed has lower oscillation as well as more stability and efficiency. The five-pole AMB has been simulated by a controller in the presence of disturbance. The results of simulation demonstrate lower vibration and oscillation in the five-pole AMB in comparison with the three-pole model.

  15. Comparative MD Simulations Indicate a Dual Role for Arg1323.50 in Dopamine-Dependent D2R Activation.

    Directory of Open Access Journals (Sweden)

    Ralf C Kling

    Full Text Available Residue Arg3.50 belongs to the highly conserved DRY-motif of class A GPCRs, which is located at the bottom of TM3. On the one hand, Arg3.50 has been reported to help stabilize the inactive state of GPCRs, but on the other hand has also been shown to be crucial for stabilizing active receptor conformations and mediating receptor-G protein coupling. The combined results of these studies suggest that the exact function of Arg3.50 is likely to be receptor-dependent and must be characterized independently for every GPCR. Consequently, we now present comparative molecular-dynamics simulations that use our recently described inactive-state and Gα-bound active-state homology models of the dopamine D2 receptor (D2R, which are either bound to dopamine or ligand-free, performed to identify the function of Arg1323.50 in D2R. Our results are consistent with a dynamic model of D2R activation in which Arg1323.50 adopts a dual role, both by stabilizing the inactive-state receptor conformation and enhancing dopamine-dependent D2R-G protein coupling.

  16. Optimal pricing decision model based on activity-based costing

    Institute of Scientific and Technical Information of China (English)

    王福胜; 常庆芳

    2003-01-01

    In order to find out the applicability of the optimal pricing decision model based on conventional costbehavior model after activity-based costing has given strong shock to the conventional cost behavior model andits assumptions, detailed analyses have been made using the activity-based cost behavior and cost-volume-profitanalysis model, and it is concluded from these analyses that the theory behind the construction of optimal pri-cing decision model is still tenable under activity-based costing, but the conventional optimal pricing decisionmodel must be modified as appropriate to the activity-based costing based cost behavior model and cost-volume-profit analysis model, and an optimal pricing decision model is really a product pricing decision model construc-ted by following the economic principle of maximizing profit.

  17. Comparing predictive models of glioblastoma multiforme built using multi-institutional and local data sources.

    Science.gov (United States)

    Singleton, Kyle W; Hsu, William; Bui, Alex A T

    2012-01-01

    The growing amount of electronic data collected from patient care and clinical trials is motivating the creation of national repositories where multiple institutions share data about their patient cohorts. Such efforts aim to provide sufficient sample sizes for data mining and predictive modeling, ultimately improving treatment recommendations and patient outcome prediction. While these repositories offer the potential to improve our understanding of a disease, potential issues need to be addressed to ensure that multi-site data and resultant predictive models are useful to non-contributing institutions. In this paper we examine the challenges of utilizing National Cancer Institute datasets for modeling glioblastoma multiforme. We created several types of prognostic models and compared their results against models generated using data solely from our institution. While overall model performance between the data sources was similar, different variables were selected during model generation, suggesting that mapping data resources between models is not a straightforward issue.

  18. A comparative study of velocity increment generation between the rigid body and flexible models of MMET

    Energy Technology Data Exchange (ETDEWEB)

    Ismail, Norilmi Amilia, E-mail: aenorilmi@usm.my [School of Aerospace Engineering, Engineering Campus, Universiti Sains Malaysia, 14300 Nibong Tebal, Pulau Pinang (Malaysia)

    2016-02-01

    The motorized momentum exchange tether (MMET) is capable of generating useful velocity increments through spin–orbit coupling. This study presents a comparative study of the velocity increments between the rigid body and flexible models of MMET. The equations of motions of both models in the time domain are transformed into a function of true anomaly. The equations of motion are integrated, and the responses in terms of the velocity increment of the rigid body and flexible models are compared and analysed. Results show that the initial conditions, eccentricity, and flexibility of the tether have significant effects on the velocity increments of the tether.

  19. Antibiotic Resistances in Livestock: A Comparative Approach to Identify an Appropriate Regression Model for Count Data

    Directory of Open Access Journals (Sweden)

    Anke Hüls

    2017-05-01

    Full Text Available Antimicrobial resistance in livestock is a matter of general concern. To develop hygiene measures and methods for resistance prevention and control, epidemiological studies on a population level are needed to detect factors associated with antimicrobial resistance in livestock holdings. In general, regression models are used to describe these relationships between environmental factors and resistance outcome. Besides the study design, the correlation structures of the different outcomes of antibiotic resistance and structural zero measurements on the resistance outcome as well as on the exposure side are challenges for the epidemiological model building process. The use of appropriate regression models that acknowledge these complexities is essential to assure valid epidemiological interpretations. The aims of this paper are (i to explain the model building process comparing several competing models for count data (negative binomial model, quasi-Poisson model, zero-inflated model, and hurdle model and (ii to compare these models using data from a cross-sectional study on antibiotic resistance in animal husbandry. These goals are essential to evaluate which model is most suitable to identify potential prevention measures. The dataset used as an example in our analyses was generated initially to study the prevalence and associated factors for the appearance of cefotaxime-resistant Escherichia coli in 48 German fattening pig farms. For each farm, the outcome was the count of samples with resistant bacteria. There was almost no overdispersion and only moderate evidence of excess zeros in the data. Our analyses show that it is essential to evaluate regression models in studies analyzing the relationship between environmental factors and antibiotic resistances in livestock. After model comparison based on evaluation of model predictions, Akaike information criterion, and Pearson residuals, here the hurdle model was judged to be the most appropriate

  20. Comparative hypoglycemic activity of different fractions of Thymus serpyllum L. in alloxan induced diabetic rabbits.

    Science.gov (United States)

    Alamgeer, -; Mushtaq, Muhammad Naveed; Bashir, Sajid; Ullah, Ikram; Karim, Sabeha; Rashid, Muhammad; Malik, Muhammad Nasir Hayat; Rashid, Haroonur

    2016-09-01

    The aim of present study was to evaluate and compare the hypoglycemic activity of different solvents extracts of Thymus serpyllum in rabbits. Diabetes was induced with single intravenous injection of alloxan monohydrate (150mg/kg). Glibenclamide and acarbose were used as standard drugs. The crude powder of Thymus serpyllum (500 mg/kg b.w) significantly reduced blood glucose level in both normal and diabetic rabbits. Various extracts of Thymus serpyllum were compared for their hypoglycemic activity in diabetic rabbits. Ether and aqueous extracts significantly reduced the blood glucose level with maximum effect (p<0.001) produced by aqueous extract, which was selected for further study. Aqueous extract significantly inhibited the rise in glucose level in oral glucose tolerance test. The extract showed synergistic effect with different doses of insulin; however serum insulin level of the diabetic rabbits was not significantly increased by the extract. HbA1c level was significantly (p<0.05) reduced whereas hemoglobin level was significantly increased in three months study. Phytochemical screening of the aqueous extract showed the presence of alkaloids, flavonoids, tannins, terpinoids, reducing sugar and cardiac glycosides. It is concluded that the aqueous extract might be used alone or in combination with insulin to manage diabetes and its associated complications.