WorldWideScience

Sample records for model systematically underestimates

  1. CMIP5 land surface models systematically underestimate inter-annual variability of net ecosystem exchange in semi-arid southwestern North America.

    Science.gov (United States)

    MacBean, N.; Scott, R. L.; Biederman, J. A.; Vuichard, N.; Hudson, A.; Barnes, M.; Fox, A. M.; Smith, W. K.; Peylin, P. P.; Maignan, F.; Moore, D. J.

    2017-12-01

    Recent studies based on analysis of atmospheric CO2 inversions, satellite data and terrestrial biosphere model simulations have suggested that semi-arid ecosystems play a dominant role in the interannual variability and long-term trend in the global carbon sink. These studies have largely cited the response of vegetation activity to changing moisture availability as the primary mechanism of variability. However, some land surface models (LSMs) used in these studies have performed poorly in comparison to satellite-based observations of vegetation dynamics in semi-arid regions. Further analysis is therefore needed to ensure semi-arid carbon cycle processes are well represented in global scale LSMs before we can fully establish their contribution to the global carbon cycle. In this study, we evaluated annual net ecosystem exchange (NEE) simulated by CMIP5 land surface models using observations from 20 Ameriflux sites across semi-arid southwestern North America. We found that CMIP5 models systematically underestimate the magnitude and sign of NEE inter-annual variability; therefore, the true role of semi-arid regions in the global carbon cycle may be even more important than previously thought. To diagnose the factors responsible for this bias, we used the ORCHIDEE LSM to test different climate forcing data, prescribed vegetation fractions and model structures. Climate and prescribed vegetation do contribute to uncertainty in annual NEE simulations, but the bias is primarily caused by incorrect timing and magnitude of peak gross carbon fluxes. Modifications to the hydrology scheme improved simulations of soil moisture in comparison to data. This in turn improved the seasonal cycle of carbon uptake due to a more realistic limitation on photosynthesis during water stress. However, the peak fluxes are still too low, and phenology is poorly represented for desert shrubs and grasses. We provide suggestions on model developments needed to tackle these issues in the future.

  2. Family and professionals underestimate quality of life across diverse cultures and health conditions: systematic review.

    Science.gov (United States)

    Crocker, Thomas F; Smith, Jaime K; Skevington, Suzanne M

    2015-05-01

    To examine how accurately proxies evaluate quality of life (QoL) in people they know, using cross-cultural data from the multidimensional, multilingual World Health Organization Quality of Life assessment short-form (the WHOQOL-BREF) and whether accuracy varies by health condition or proxy type (eg, family/professional). Systematic review with meta-analysis: We searched five databases for reports of proxy-completed WHOQOL-BREF scores and aggregated results using a random-effects model. Minimal clinically important difference values were calculated. Analyses included nine studies (1980 dyads) of physical (n = 762) or mental (n = 604) health conditions, or intellectual disability (n = 614), in 10 countries. Mean person-proxy correlations ranged from 0.28 (social QoL) to 0.44 (physical QoL). Proxy measures were underestimates (ie, significantly lower than persons reported for themselves) for social [mean difference (MD) = 4.7, 95% confidence interval (CI): 1.8, 7.6], psychological (MD = 3.7, 95% CI: 0.6, 6.8), and physical (MD = 3.1, 95% CI: 0.6, 5.6) QoL. Underestimates varied significantly between health conditions for social (P Family members assessed psychological and environmental QoL better than professionals. Proxies tend to be imprecise, underestimating QoL, and should be aware of this tendency. Where health care is decided for others, family members' views about QoL should be prioritized. Copyright © 2015 Elsevier Inc. All rights reserved.

  3. Midlatitude Summer Drying: An Underestimated Threat in CMIP5 Models?

    Science.gov (United States)

    Douville, H.; Plazzotta, M.

    2017-10-01

    Early assessments of the hydrological impacts of global warming suggested both an intensification of the global water cycle and an expansion of dry areas. Yet these alarming conclusions were challenged by a number of latter studies emphasizing the lack of evidence in observations and historical simulations, as well as the large uncertainties in climate projections from the fifth phase of the Coupled Model Intercomparison Project (CMIP5). Here several aridity indices and a two-tier attribution strategy are used to demonstrate that a summer midlatitude drying has recently emerged over the northern continents, which is mainly attributable to anthropogenic climate change. This emerging signal is shown to be the harbinger of a long-term drying in the CMIP5 projections. Linear trends in the observed aridity indices can therefore be used as observational constraints and suggest that the projected midlatitude summer drying was underestimated by most CMIP5 models. Mitigating global warming therefore remains a priority to avoid dangerous impacts on global water and food security.

  4. Earth System Models Underestimate Soil Carbon Diagnostic Times in Dry and Cold Regions.

    Science.gov (United States)

    Jing, W.; Xia, J.; Zhou, X.; Huang, K.; Huang, Y.; Jian, Z.; Jiang, L.; Xu, X.; Liang, J.; Wang, Y. P.; Luo, Y.

    2017-12-01

    Soils contain the largest organic carbon (C) reservoir in the Earth's surface and strongly modulate the terrestrial feedback to climate change. Large uncertainty exists in current Earth system models (ESMs) in simulating soil organic C (SOC) dynamics, calling for a systematic diagnosis on their performance based on observations. Here, we built a global database of SOC diagnostic time (i.e.,turnover times; τsoil) measured at 320 sites with four different approaches. We found that the estimated τsoil was comparable among approaches of 14C dating () (median with 25 and 75 percentiles), 13C shifts due to vegetation change () and the ratio of stock over flux (), but was shortest from laboratory incubation studies (). The state-of-the-art ESMs underestimated the τsoil in most biomes, even by >10 and >5 folds in cold and dry regions, respectively. Moreover,we identified clear negative dependences of τsoil on temperature and precipitation in both of the observational and modeling results. Compared with Community Land Model (version 4), the incorporation of soil vertical profile (CLM4.5) could substantially extend the τsoil of SOC. Our findings suggest the accuracy of climate-C cycle feedback in current ESMs could be enhanced by an improved understanding of SOC dynamics under the limited hydrothermal conditions.

  5. Maximum rates of climate change are systematically underestimated in the geological record.

    Science.gov (United States)

    Kemp, David B; Eichenseer, Kilian; Kiessling, Wolfgang

    2015-11-10

    Recently observed rates of environmental change are typically much higher than those inferred for the geological past. At the same time, the magnitudes of ancient changes were often substantially greater than those established in recent history. The most pertinent disparity, however, between recent and geological rates is the timespan over which the rates are measured, which typically differ by several orders of magnitude. Here we show that rates of marked temperature changes inferred from proxy data in Earth history scale with measurement timespan as an approximate power law across nearly six orders of magnitude (10(2) to >10(7) years). This scaling reveals how climate signals measured in the geological record alias transient variability, even during the most pronounced climatic perturbations of the Phanerozoic. Our findings indicate that the true attainable pace of climate change on timescales of greatest societal relevance is underestimated in geological archives.

  6. Evidence for link between modelled trends in Antarctic sea ice and underestimated westerly wind changes.

    Science.gov (United States)

    Purich, Ariaan; Cai, Wenju; England, Matthew H; Cowan, Tim

    2016-02-04

    Despite global warming, total Antarctic sea ice coverage increased over 1979-2013. However, the majority of Coupled Model Intercomparison Project phase 5 models simulate a decline. Mechanisms causing this discrepancy have so far remained elusive. Here we show that weaker trends in the intensification of the Southern Hemisphere westerly wind jet simulated by the models may contribute to this disparity. During austral summer, a strengthened jet leads to increased upwelling of cooler subsurface water and strengthened equatorward transport, conducive to increased sea ice. As the majority of models underestimate summer jet trends, this cooling process is underestimated compared with observations and is insufficient to offset warming in the models. Through the sea ice-albedo feedback, models produce a high-latitude surface ocean warming and sea ice decline, contrasting the observed net cooling and sea ice increase. A realistic simulation of observed wind changes may be crucial for reproducing the recent observed sea ice increase.

  7. How systematic age underestimation can impede understanding of fish population dynamics: Lessons learned from a Lake Superior cisco stock

    Science.gov (United States)

    Yule, D.L.; Stockwell, J.D.; Black, J.A.; Cullis, K.I.; Cholwek, G.A.; Myers, J.T.

    2008-01-01

    Systematic underestimation of fish age can impede understanding of recruitment variability and adaptive strategies (like longevity) and can bias estimates of survivorship. We suspected that previous estimates of annual survival (S; range = 0.20-0.44) for Lake Superior ciscoes Coregonus artedi developed from scale ages were biased low. To test this hypothesis, we estimated the total instantaneous mortality rate of adult ciscoes from the Thunder Bay, Ontario, stock by use of cohort-based catch curves developed from commercial gill-net catches and otolith-aged fish. Mean S based on otolith ages was greater for adult females (0.80) than for adult males (0.75), but these differences were not significant. Applying the results of a study of agreement between scale and otolith ages, we modeled a scale age for each otolith-aged fish to reconstruct catch curves. Using modeled scale ages, estimates of S (0.42 for females, 0.36 for males) were comparable with those reported in past studies. We conducted a November 2005 acoustic and midwater trawl survey to estimate the abundance of ciscoes when the fish were being harvested for roe. Estimated exploitation rates were 0.085 for females and 0.025 for males, and the instantaneous rates of fishing mortality were 0.089 for females and 0.025 for males. The instantaneous rates of natural mortality were 0.131 and 0.265 for females and males, respectively. Using otolith ages, we found that strong year-classes at large during November 2005 were caught in high numbers as age-1 fish in previous annual bottom trawl surveys, whereas weak or absent year-classes were not. For decades, large-scale fisheries on the Great Lakes were allowed to operate because ciscoes were assumed to be short lived and to have regular recruitment. We postulate that the collapse of these fisheries was linked in part to a misunderstanding of cisco biology driven by scale-ageing error. ?? Copyright by the American Fisheries Society 2008.

  8. Global models underestimate large decadal declining and rising water storage trends relative to GRACE satellite data.

    Science.gov (United States)

    Scanlon, Bridget R; Zhang, Zizhan; Save, Himanshu; Sun, Alexander Y; Müller Schmied, Hannes; van Beek, Ludovicus P H; Wiese, David N; Wada, Yoshihide; Long, Di; Reedy, Robert C; Longuevergne, Laurent; Döll, Petra; Bierkens, Marc F P

    2018-02-06

    Assessing reliability of global models is critical because of increasing reliance on these models to address past and projected future climate and human stresses on global water resources. Here, we evaluate model reliability based on a comprehensive comparison of decadal trends (2002-2014) in land water storage from seven global models (WGHM, PCR-GLOBWB, GLDAS NOAH, MOSAIC, VIC, CLM, and CLSM) to trends from three Gravity Recovery and Climate Experiment (GRACE) satellite solutions in 186 river basins (∼60% of global land area). Medians of modeled basin water storage trends greatly underestimate GRACE-derived large decreasing (≤-0.5 km 3 /y) and increasing (≥0.5 km 3 /y) trends. Decreasing trends from GRACE are mostly related to human use (irrigation) and climate variations, whereas increasing trends reflect climate variations. For example, in the Amazon, GRACE estimates a large increasing trend of ∼43 km 3 /y, whereas most models estimate decreasing trends (-71 to 11 km 3 /y). Land water storage trends, summed over all basins, are positive for GRACE (∼71-82 km 3 /y) but negative for models (-450 to -12 km 3 /y), contributing opposing trends to global mean sea level change. Impacts of climate forcing on decadal land water storage trends exceed those of modeled human intervention by about a factor of 2. The model-GRACE comparison highlights potential areas of future model development, particularly simulated water storage. The inability of models to capture large decadal water storage trends based on GRACE indicates that model projections of climate and human-induced water storage changes may be underestimated. Copyright © 2018 the Author(s). Published by PNAS.

  9. Use of the LQ model with large fraction sizes results in underestimation of isoeffect doses

    International Nuclear Information System (INIS)

    Sheu, Tommy; Molkentine, Jessica; Transtrum, Mark K.; Buchholz, Thomas A.; Withers, Hubert Rodney; Thames, Howard D.; Mason, Kathy A.

    2013-01-01

    Purpose: To test the appropriateness of the linear-quadratic (LQ) model to describe survival of jejunal crypt clonogens after split doses with variable (small 1–6 Gy, large 8–13 Gy) first dose, as a model of its appropriateness for both small and large fraction sizes. Methods: C3Hf/KamLaw mice were exposed to whole body irradiation using 300 kVp X-rays at a dose rate of 1.84 Gy/min, and the number of viable jejunal crypts was determined using the microcolony assay. 14 Gy total dose was split into unequal first and second fractions separated by 4 h. Data were analyzed using the LQ model, the lethal potentially lethal (LPL) model, and a repair-saturation (RS) model. Results: Cell kill was greater in the group receiving the larger fraction first, creating an asymmetry in the plot of survival vs size of first dose, as opposed to the prediction of the LQ model of a symmetric response. There was a significant difference in the estimated βs (higher β after larger first doses), but no significant difference in the αs, when large doses were given first vs small doses first. This difference results in underestimation (based on present data by approximately 8%) of isoeffect doses using LQ model parameters based on small fraction sizes. While the LPL model also predicted a symmetric response inconsistent with the data, the RS model results were consistent with the observed asymmetry. Conclusion: The LQ model underestimates doses for isoeffective crypt-cell survival with large fraction sizes (in the present setting, >9 Gy)

  10. Low modeled ozone production suggests underestimation of precursor emissions (especially NOx in Europe

    Directory of Open Access Journals (Sweden)

    E. Oikonomakis

    2018-02-01

    Full Text Available High surface ozone concentrations, which usually occur when photochemical ozone production takes place, pose a great risk to human health and vegetation. Air quality models are often used by policy makers as tools for the development of ozone mitigation strategies. However, the modeled ozone production is often not or not enough evaluated in many ozone modeling studies. The focus of this work is to evaluate the modeled ozone production in Europe indirectly, with the use of the ozone–temperature correlation for the summer of 2010 and to analyze its sensitivity to precursor emissions and meteorology by using the regional air quality model, the Comprehensive Air Quality Model with Extensions (CAMx. The results show that the model significantly underestimates the observed high afternoon surface ozone mixing ratios (≥  60 ppb by 10–20 ppb and overestimates the lower ones (<  40 ppb by 5–15 ppb, resulting in a misleading good agreement with the observations for average ozone. The model also underestimates the ozone–temperature regression slope by about a factor of 2 for most of the measurement stations. To investigate the impact of emissions, four scenarios were tested: (i increased volatile organic compound (VOC emissions by a factor of 1.5 and 2 for the anthropogenic and biogenic VOC emissions, respectively, (ii increased nitrogen oxide (NOx emissions by a factor of 2, (iii a combination of the first two scenarios and (iv increased traffic-only NOx emissions by a factor of 4. For southern, eastern, and central (except the Benelux area Europe, doubling NOx emissions seems to be the most efficient scenario to reduce the underestimation of the observed high ozone mixing ratios without significant degradation of the model performance for the lower ozone mixing ratios. The model performance for ozone–temperature correlation is also better when NOx emissions are doubled. In the Benelux area, however, the third scenario

  11. Modeling microelectrode biosensors: free-flow calibration can substantially underestimate tissue concentrations.

    Science.gov (United States)

    Newton, Adam J H; Wall, Mark J; Richardson, Magnus J E

    2017-03-01

    Microelectrode amperometric biosensors are widely used to measure concentrations of analytes in solution and tissue including acetylcholine, adenosine, glucose, and glutamate. A great deal of experimental and modeling effort has been directed at quantifying the response of the biosensors themselves; however, the influence that the macroscopic tissue environment has on biosensor response has not been subjected to the same level of scrutiny. Here we identify an important issue in the way microelectrode biosensors are calibrated that is likely to have led to underestimations of analyte tissue concentrations. Concentration in tissue is typically determined by comparing the biosensor signal to that measured in free-flow calibration conditions. In a free-flow environment the concentration of the analyte at the outer surface of the biosensor can be considered constant. However, in tissue the analyte reaches the biosensor surface by diffusion through the extracellular space. Because the enzymes in the biosensor break down the analyte, a density gradient is set up resulting in a significantly lower concentration of analyte near the biosensor surface. This effect is compounded by the diminished volume fraction (porosity) and reduction in the diffusion coefficient due to obstructions (tortuosity) in tissue. We demonstrate this effect through modeling and experimentally verify our predictions in diffusive environments. NEW & NOTEWORTHY Microelectrode biosensors are typically calibrated in a free-flow environment where the concentrations at the biosensor surface are constant. However, when in tissue, the analyte reaches the biosensor via diffusion and so analyte breakdown by the biosensor results in a concentration gradient and consequently a lower concentration around the biosensor. This effect means that naive free-flow calibration will underestimate tissue concentration. We develop mathematical models to better quantify the discrepancy between the calibration and tissue

  12. Low modeled ozone production suggests underestimation of precursor emissions (especially NOx) in Europe

    Science.gov (United States)

    Oikonomakis, Emmanouil; Aksoyoglu, Sebnem; Ciarelli, Giancarlo; Baltensperger, Urs; Prévôt, André Stephan Henry

    2018-02-01

    High surface ozone concentrations, which usually occur when photochemical ozone production takes place, pose a great risk to human health and vegetation. Air quality models are often used by policy makers as tools for the development of ozone mitigation strategies. However, the modeled ozone production is often not or not enough evaluated in many ozone modeling studies. The focus of this work is to evaluate the modeled ozone production in Europe indirectly, with the use of the ozone-temperature correlation for the summer of 2010 and to analyze its sensitivity to precursor emissions and meteorology by using the regional air quality model, the Comprehensive Air Quality Model with Extensions (CAMx). The results show that the model significantly underestimates the observed high afternoon surface ozone mixing ratios (≥ 60 ppb) by 10-20 ppb and overestimates the lower ones (emissions, four scenarios were tested: (i) increased volatile organic compound (VOC) emissions by a factor of 1.5 and 2 for the anthropogenic and biogenic VOC emissions, respectively, (ii) increased nitrogen oxide (NOx) emissions by a factor of 2, (iii) a combination of the first two scenarios and (iv) increased traffic-only NOx emissions by a factor of 4. For southern, eastern, and central (except the Benelux area) Europe, doubling NOx emissions seems to be the most efficient scenario to reduce the underestimation of the observed high ozone mixing ratios without significant degradation of the model performance for the lower ozone mixing ratios. The model performance for ozone-temperature correlation is also better when NOx emissions are doubled. In the Benelux area, however, the third scenario (where both NOx and VOC emissions are increased) leads to a better model performance. Although increasing only the traffic NOx emissions by a factor of 4 gave very similar results to the doubling of all NOx emissions, the first scenario is more consistent with the uncertainties reported by other studies than

  13. Terrestrial biosphere models underestimate photosynthetic capacity and CO2 assimilation in the Arctic.

    Science.gov (United States)

    Rogers, Alistair; Serbin, Shawn P; Ely, Kim S; Sloan, Victoria L; Wullschleger, Stan D

    2017-12-01

    Terrestrial biosphere models (TBMs) are highly sensitive to model representation of photosynthesis, in particular the parameters maximum carboxylation rate and maximum electron transport rate at 25°C (V c,max.25 and J max.25 , respectively). Many TBMs do not include representation of Arctic plants, and those that do rely on understanding and parameterization from temperate species. We measured photosynthetic CO 2 response curves and leaf nitrogen (N) content in species representing the dominant vascular plant functional types found on the coastal tundra near Barrow, Alaska. The activation energies associated with the temperature response functions of V c,max and J max were 17% lower than commonly used values. When scaled to 25°C, V c,max.25 and J max.25 were two- to five-fold higher than the values used to parameterize current TBMs. This high photosynthetic capacity was attributable to a high leaf N content and the high fraction of N invested in Rubisco. Leaf-level modeling demonstrated that current parameterization of TBMs resulted in a two-fold underestimation of the capacity for leaf-level CO 2 assimilation in Arctic vegetation. This study highlights the poor representation of Arctic photosynthesis in TBMs, and provides the critical data necessary to improve our ability to project the response of the Arctic to global environmental change. No claim to original US Government works. New Phytologist © 2017 New Phytologist Trust.

  14. Method for activity measurement in large packages of radioactive wastes. Is the overall activity stored inside a final repository systematically under-estimated?

    International Nuclear Information System (INIS)

    Rottner, B.

    2005-01-01

    The activity of a rad waste package is usually evaluated from gamma spectrometry measurements or dose rates emitted by the package, associated with transfer functions. These functions are calculated assuming that both activity and mass distributions are homogeneous. The proposed method, OPROF-STAT (patented) evaluates the error arising from this homogeneous assumption. This error has a systematic part, leading to an over or underestimation of the overall activity in a family of similar waste packages, and a stochastic part, whose mean effect on the overall activity of the family is null. The method consists in building a virtual family of packages, by numeric simulation of the filling of each package of the family. The simulated filling has a stochastic part, so that the mass and activity distributions inside a package are different from one package to another. The virtual packages are wholly known, which is not the case for the real family, and it is then possible to compute the result of a measurement, and the associated error, for each package of the virtual family. A way to fit and demonstrate the representativeness of the virtual is described. The main trends and parameters modifying the error are explored: a systematic underestimation of the activity in a large family of rad waste packages is possible. (author)

  15. Underestimation of Project Costs

    Science.gov (United States)

    Jones, Harry W.

    2015-01-01

    Large projects almost always exceed their budgets. Estimating cost is difficult and estimated costs are usually too low. Three different reasons are suggested: bad luck, overoptimism, and deliberate underestimation. Project management can usually point to project difficulty and complexity, technical uncertainty, stakeholder conflicts, scope changes, unforeseen events, and other not really unpredictable bad luck. Project planning is usually over-optimistic, so the likelihood and impact of bad luck is systematically underestimated. Project plans reflect optimism and hope for success in a supposedly unique new effort rather than rational expectations based on historical data. Past project problems are claimed to be irrelevant because "This time it's different." Some bad luck is inevitable and reasonable optimism is understandable, but deliberate deception must be condemned. In a competitive environment, project planners and advocates often deliberately underestimate costs to help gain project approval and funding. Project benefits, cost savings, and probability of success are exaggerated and key risks ignored. Project advocates have incentives to distort information and conceal difficulties from project approvers. One naively suggested cure is more openness, honesty, and group adherence to shared overall goals. A more realistic alternative is threatening overrun projects with cancellation. Neither approach seems to solve the problem. A better method to avoid the delusions of over-optimism and the deceptions of biased advocacy is to base the project cost estimate on the actual costs of a large group of similar projects. Over optimism and deception can continue beyond the planning phase and into project execution. Hard milestones based on verified tests and demonstrations can provide a reality check.

  16. Effects of underestimating the kinematics of trunk rotation on simultaneous reaching movements: predictions of a biomechanical model.

    Science.gov (United States)

    Simoneau, Martin; Guillaud, Étienne; Blouin, Jean

    2013-06-12

    Rotation of the torso while reaching produces torques (e.g., Coriolis torque) that deviate the arm from its planned trajectory. To ensure an accurate reaching movement, the brain may take these perturbing torques into account during movement planning or, alternatively, it may correct hand trajectory during movement execution. Irrespective of the process selected, it is expected that an underestimation of trunk rotation would likely induce inaccurate shoulder and elbow torques, resulting in hand deviation. Nonetheless, it is still undetermined to what extent a small error in the perception of trunk rotations, translating into an inappropriate selection of motor commands, would affect reaching accuracy. To investigate, we adapted a biomechanical model (J Neurophysiol 89: 276-289, 2003) to predict the consequences of underestimating trunk rotations on right hand reaching movements performed during either clockwise or counter clockwise torso rotations. The results revealed that regardless of the degree to which the torso rotation was underestimated, the amplitude of hand deviation was much larger for counter clockwise rotations than for clockwise rotations. This was attributed to the fact that the Coriolis and centripetal joint torques were acting in the same direction during counter clockwise rotation yet in opposite directions during clockwise rotations, effectively cancelling each other out. These findings suggest that in order to anticipate and compensate for the interaction torques generated during torso rotation while reaching, the brain must have an accurate prediction of torso rotation kinematics. The present study proposes that when designing upper limb prostheses controllers, adding a sensor to monitor trunk kinematics may improve prostheses control and performance.

  17. Low modeled ozone production suggests underestimation of precursor emissions (especially NOx) in Europe

    OpenAIRE

    Oikonomakis, Emmanouil; Aksoyoglu, Sebnem; Ciarelli, Giancarlo; Baltensperger, Urs; Prévôt, André Stephan Henry

    2018-01-01

    High surface ozone concentrations, which usually occur when photochemical ozone production takes place, pose a great risk to human health and vegetation. Air quality models are often used by policy makers as tools for the development of ozone mitigation strategies. However, the modeled ozone production is often not or not enough evaluated in many ozone modeling studies. The focus of this work is to evaluate the modeled ozone production in Europe indirectly, with the use of t...

  18. How coagulation zone size is underestimated in computer modeling of RF ablation by ignoring the cooling phase just after RF power is switched off.

    Science.gov (United States)

    Irastorza, Ramiro M; Trujillo, Macarena; Berjano, Enrique

    2017-11-01

    All the numerical models developed for radiofrequency ablation so far have ignored the possible effect of the cooling phase (just after radiofrequency power is switched off) on the dimensions of the coagulation zone. Our objective was thus to quantify the differences in the minor radius of the coagulation zone computed by including and ignoring the cooling phase. We built models of RF tumor ablation with 2 needle-like electrodes: a dry electrode (5 mm long and 17G in diameter) with a constant temperature protocol (70°C) and a cooled electrode (30 mm long and 17G in diameter) with a protocol of impedance control. We observed that the computed coagulation zone dimensions were always underestimated when the cooling phase was ignored. The mean values of the differences computed along the electrode axis were always lower than 0.15 mm for the dry electrode and 1.5 mm for the cooled electrode, which implied a value lower than 5% of the minor radius of the coagulation zone (which was 3 mm for the dry electrode and 30 mm for the cooled electrode). The underestimation was found to be dependent on the tissue characteristics: being more marked for higher values of specific heat and blood perfusion and less marked for higher values of thermal conductivity. Copyright © 2017 John Wiley & Sons, Ltd.

  19. Low modeled ozone production suggests underestimation of precursor emissions (especially NOx) in Europe

    OpenAIRE

    E. Oikonomakis; S. Aksoyoglu; G. Ciarelli; U. Baltensperger; A. S. H. Prévôt

    2018-01-01

    High surface ozone concentrations, which usually occur when photochemical ozone production takes place, pose a great risk to human health and vegetation. Air quality models are often used by policy makers as tools for the development of ozone mitigation strategies. However, the modeled ozone production is often not or not enough evaluated in many ozone modeling studies. The focus of this work is to evaluate the modeled ozone production in Europe indirectly, with the use of t...

  20. Underestimation of adolescent obesity.

    Science.gov (United States)

    Buttenheim, Alison M; Goldman, Noreen; Pebley, Anne R

    2013-01-01

    Previous studies assessing the validity of adolescent self-reported height and weight for estimating obesity prevalence have not accounted for, potential bias due to nonresponse in self-reports. The aim of this study was to assess the implications of selective nonresponse in self-reports of height and weight for estimates of adolescent obesity. The authors analyzed 613 adolescents ages 12-17 years from the 2006-2008 Los Angeles Family and Neighborhood Survey, a longitudinal study of Los Angeles County households with an oversample of poor neighborhoods. Obesity prevalence estimates were compared based on (a) self-report, (b) measured height and weight for those who did report, and (c) measured height and weight for those who did report. Among younger teens, measured obesity prevalence was higher for those who did not report height and weight compared with those who did (40% vs. 30%). Consequently, obesity prevalence based on self-reported height and weight underestimated measured prevalence by 12 percentage points (when accounting for nonresponse) versus 9 percentage points (when nonresponse was not accounted for). Results were robust to the choice of difference child growth references. Adolescent obesity surveillance and prevention efforts must take into account selective nonresponse for self-reported height and weight, particularly for younger teens. Results should be replicated in a nationally representative sample.

  1. Underestimation of Adolescent Obesity

    Science.gov (United States)

    Buttenheim, Alison M.; Gol, Noreen; Pebley, Anne R.

    2014-01-01

    Background Previous studies assessing the validity of adolescent self-reported height and weight for estimating obesity prevalence have not accounted for potential bias due to non-response in self-reports. Objectives The purpose of this study was to assess the implications of selective non-response in self-reports of height and weight for estimates of adolescent obesity. Methods The authors analyzed 613 adolescents ages 12-17 from the 2006-08 Los Angeles Family and Neighborhood Survey, a longitudinal study of Los Angeles County households with an oversample of poor neighborhoods. Obesity prevalence estimates based on (1) self-report, (2) measured height and weight for those who did report, and (3) measured height and weight for those who did not report were compared. Results Among younger teens, measured obesity prevalence was higher for those who did not report height and weight compared to those who did (40% vs. 30). Consequently, obesity prevalence based on self-reported height and weight underestimated measured prevalence by 12 percentage points (when accounting for non-response) vs. 9 percentage points (when non-response was not accounted for). Results were robust to the choice of difference child growth references (i.e,, CDC vs. International Obesity Task Force). Discussion Adolescent obesity surveillance and prevention efforts must take into account selective non-response for self-reported height and weight, particularly for younger teens. Results should be replicated in a nationally-representative sample. PMID:23636345

  2. Underestimating Costs in Public Works Projects

    DEFF Research Database (Denmark)

    Flyvbjerg, Bent; Holm, Mette K. Skamris; Buhl, Søren L.

    2002-01-01

    questions of cost underestimation and escalation for different project types, different geographical regions, and different historical periods. Four kinds of explanation of cost underestimation are examined: technical, economic, psychological, and political. Underestimation cannot be explained by error......This article presents results from the first statistically significant study of cost escalation in transportation infrastructure projects. Based on a sample of 258 transportation infrastructure projects worth $90 billion (U.S.), it is found with overwhelming statistical significance that the cost...... estimates used to decide whether important infrastructure should be built are highly and systematically misleading. The result is continuous cost escalation of billions of dollars. The sample used in the study is the largest of its kind, allowing for the first time statistically valid conclusions regarding...

  3. Cost Underestimation in Public Works Projects

    DEFF Research Database (Denmark)

    Flyvbjerg, Bent; Holm, Mette K. Skamris; Buhl, Søren L.

    questions of cost underestimation and escalation for different project types, different geographical regions, and different historical periods. Four kinds of explanation of cost underestimation are examined: technical, economic, psychological, and political. Underestimation cannot be explained by error......This article presents results from the first statistically significant study of cost escalation in transportation infrastructure projects. Based on a sample of 258 transportation infrastructure projects worth $90 billion (U.S.), it is found with overwhelming statistical significance that the cost...... estimates used to decide whether important infrastructure should be built are highly and systematically misleading. The result is continuous cost escalation of billions of dollars. The sample used in the study is the largest of its kind, allowing for the first time statistically valid conclusions regarding...

  4. Development and evaluation of a prediction model for underestimated invasive breast cancer in women with ductal carcinoma in situ at stereotactic large core needle biopsy.

    Directory of Open Access Journals (Sweden)

    Suzanne C E Diepstraten

    Full Text Available BACKGROUND: We aimed to develop a multivariable model for prediction of underestimated invasiveness in women with ductal carcinoma in situ at stereotactic large core needle biopsy, that can be used to select patients for sentinel node biopsy at primary surgery. METHODS: From the literature, we selected potential preoperative predictors of underestimated invasive breast cancer. Data of patients with nonpalpable breast lesions who were diagnosed with ductal carcinoma in situ at stereotactic large core needle biopsy, drawn from the prospective COBRA (Core Biopsy after RAdiological localization and COBRA2000 cohort studies, were used to fit the multivariable model and assess its overall performance, discrimination, and calibration. RESULTS: 348 women with large core needle biopsy-proven ductal carcinoma in situ were available for analysis. In 100 (28.7% patients invasive carcinoma was found at subsequent surgery. Nine predictors were included in the model. In the multivariable analysis, the predictors with the strongest association were lesion size (OR 1.12 per cm, 95% CI 0.98-1.28, number of cores retrieved at biopsy (OR per core 0.87, 95% CI 0.75-1.01, presence of lobular cancerization (OR 5.29, 95% CI 1.25-26.77, and microinvasion (OR 3.75, 95% CI 1.42-9.87. The overall performance of the multivariable model was poor with an explained variation of 9% (Nagelkerke's R(2, mediocre discrimination with area under the receiver operating characteristic curve of 0.66 (95% confidence interval 0.58-0.73, and fairly good calibration. CONCLUSION: The evaluation of our multivariable prediction model in a large, clinically representative study population proves that routine clinical and pathological variables are not suitable to select patients with large core needle biopsy-proven ductal carcinoma in situ for sentinel node biopsy during primary surgery.

  5. SU-F-T-132: Variable RBE Models Predict Possible Underestimation of Vaginal Dose for Anal Cancer Patients Treated Using Single-Field Proton Treatments

    Energy Technology Data Exchange (ETDEWEB)

    McNamara, A; Underwood, T; Wo, J; Paganetti, H [Massachusetts General Hospital & Harvard Medical School, Boston, MA (United States)

    2016-06-15

    Purpose: Anal cancer patients treated using a posterior proton beam may be at risk of vaginal wall injury due to the increased linear energy transfer (LET) and relative biological effectiveness (RBE) at the beam distal edge. We investigate the vaginal dose received. Methods: Five patients treated for anal cancer with proton pencil beam scanning were considered, all treated to a prescription dose of 54 Gy(RBE) over 28–30 fractions. Dose and LET distributions were calculated using the Monte Carlo simulation toolkit TOPAS. In addition to the standard assumption of a fixed RBE of 1.1, variable RBE was considered via the application of published models. Dose volume histograms (DVHs) were extracted for the planning treatment volume (PTV) and vagina, the latter being used to calculate the vaginal normal tissue complication probability (NTCP). Results: Compared to the assumption of a fixed RBE of 1.1, the variable RBE model predicts a dose increase of approximately 3.3 ± 1.7 Gy at the end of beam range. NTCP parameters for the vagina are incomplete in the current literature, however, inferring value ranges from the existing data we use D{sub 50} = 50 Gy and LKB model parameters a=1–2 and m=0.2–0.4. We estimate the NTCP for the vagina to be 37–48% and 42–47% for the fixed and variable RBE cases, respectively. Additionally, a difference in the dose distribution was observed between the analytical calculation and Monte Carlo methods. We find that the target dose is overestimated on average by approximately 1–2%. Conclusion: For patients treated with posterior beams, the vaginal wall may coincide with the distal end of the proton beam and may receive a substantial increase in dose if variable RBE models are applied compared to using the current clinical standard of RBE equal to 1.1. This could potentially lead to underestimating toxicities when treating with protons.

  6. A Bayesian model to correct underestimated 3-D wind speeds from sonic anemometers increases turbulent components of the surface energy balance

    Science.gov (United States)

    John M. Frank; William J. Massman; Brent E. Ewers

    2016-01-01

    Sonic anemometers are the principal instruments in micrometeorological studies of turbulence and ecosystem fluxes. Common designs underestimate vertical wind measurements because they lack a correction for transducer shadowing, with no consensus on a suitable correction. We reanalyze a subset of data collected during field experiments in 2011 and 2013 featuring two or...

  7. Systematic modelling and simulation of refrigeration systems

    DEFF Research Database (Denmark)

    Rasmussen, Bjarne D.; Jakobsen, Arne

    1998-01-01

    The task of developing a simulation model of a refrigeration system can be very difficult and time consuming. In order for this process to be effective, a systematic method for developing the system model is required. This method should aim at guiding the developer to clarify the purpose of the s......The task of developing a simulation model of a refrigeration system can be very difficult and time consuming. In order for this process to be effective, a systematic method for developing the system model is required. This method should aim at guiding the developer to clarify the purpose...... of the simulation, to select appropriate component models and to set up the equations in a well-arranged way. In this paper the outline of such a method is proposed and examples showing the use of this method for simulation of refrigeration systems are given....

  8. Underestimation of risk due to exposure misclassification

    DEFF Research Database (Denmark)

    Grandjean, Philippe; Budtz-Jørgensen, Esben; Keiding, Niels

    2004-01-01

    . These findings illustrate that measurement error may be greatly underestimated if judged solely from reproducibility or laboratory quality data. Adjustment by sensitivity analysis is meaningful only if realistic measurement errors are applied. When exposure measurement errors are overlooked or underestimated...

  9. A SYSTEMATIC STUDY OF SOFTWARE QUALITY MODELS

    OpenAIRE

    Dr.Vilas. M. Thakare; Ashwin B. Tomar

    2011-01-01

    This paper aims to provide a basis for software quality model research, through a systematic study ofpapers. It identifies nearly seventy software quality research papers from journals and classifies paper asper research topic, estimation approach, study context and data set. The paper results combined withother knowledge provides support for recommendations in future software quality model research, toincrease the area of search for relevant studies, carefully select the papers within a set ...

  10. Thermal sensation models: a systematic comparison.

    Science.gov (United States)

    Koelblen, B; Psikuta, A; Bogdan, A; Annaheim, S; Rossi, R M

    2017-05-01

    Thermal sensation models, capable of predicting human's perception of thermal surroundings, are commonly used to assess given indoor conditions. These models differ in many aspects, such as the number and type of input conditions, the range of conditions in which the models can be applied, and the complexity of equations. Moreover, the models are associated with various thermal sensation scales. In this study, a systematic comparison of seven existing thermal sensation models has been performed with regard to exposures including various air temperatures, clothing thermal insulation, and metabolic rate values after a careful investigation of the models' range of applicability. Thermo-physiological data needed as input for some of the models were obtained from a mathematical model for human physiological responses. The comparison showed differences between models' predictions for the analyzed conditions, mostly higher than typical intersubject differences in votes. Therefore, it can be concluded that the choice of model strongly influences the assessment of indoor spaces. The issue of comparing different thermal sensation scales has also been discussed. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  11. Malnutrition in older persons: underestimated, underdiagnosed and ...

    African Journals Online (AJOL)

    The right of older persons to enjoy optimal health and live in a dignified manner is protected in various international ... multi-model interventions that target frail and pre-disabled older persons could prevent or reverse ... to hospital admissions.20 Systematic inspection of the oral cavity is, therefore, crucial as a part of the ...

  12. Post-stroke seizures are clinically underestimated.

    Science.gov (United States)

    Bentes, Carla; Martins, Hugo; Peralta, Ana Rita; Casimiro, Carlos; Morgado, Carlos; Franco, Ana Catarina; Fonseca, Ana Catarina; Geraldes, Ruth; Canhão, Patrícia; Pinho E Melo, Teresa; Paiva, Teresa; Ferro, José M

    2017-09-01

    Cerebrovascular disease is the leading cause of epilepsy in adults, although post-stroke seizures reported frequency is variable and few studies used EEG in their identification. To describe and compare EEG and clinical epileptic manifestations frequency in patients with an anterior circulation ischaemic stroke. Prospective study of acute anterior circulation ischaemic stroke patients, consecutively admitted to a Stroke Unit over 24 months and followed-up for 1 year. All patients underwent standardized clinical and diagnostic assessment. Seizure occurrence was clinically evaluated during hospitalization and by a telephone interview at 6 months and a clinical appointment at 12 months after stroke. Video-EEG was performed in the first 72 h (1st EEG), daily after the 1st EEG for the first 7 days after the stroke, or later if neurological worsening, at discharge, and at 12 months. 151 patients were included (112 men) with a mean age of 67.4 (11.9) years. In the 1st year after stroke, 38 patients (25.2%) had an epileptic seizure. During hospitalization, 27 patients (17.9%) had epileptiform activity (interictal or ictal) in the EEG, 7 (25.9%) of them electrographic seizures. During the first week after stroke, 22 (14.6%) patients had a seizure and 4 (2.6%) non-convulsive status epilepticus criteria. Five (22.7%) acute symptomatic seizures were exclusively electrographic. At least one remote symptomatic seizure occurred in 23 (16%) patients. In the first 7 days after stroke, more than one-fifth of patients with seizures had exclusively electrographic seizures. Without a systematic neurophysiological evaluation the frequency of post-stroke seizures are clinically underestimated.

  13. Systematic model building with flavor symmetries

    Energy Technology Data Exchange (ETDEWEB)

    Plentinger, Florian

    2009-12-19

    The observation of neutrino masses and lepton mixing has highlighted the incompleteness of the Standard Model of particle physics. In conjunction with this discovery, new questions arise: why are the neutrino masses so small, which form has their mass hierarchy, why is the mixing in the quark and lepton sectors so different or what is the structure of the Higgs sector. In order to address these issues and to predict future experimental results, different approaches are considered. One particularly interesting possibility, are Grand Unified Theories such as SU(5) or SO(10). GUTs are vertical symmetries since they unify the SM particles into multiplets and usually predict new particles which can naturally explain the smallness of the neutrino masses via the seesaw mechanism. On the other hand, also horizontal symmetries, i.e., flavor symmetries, acting on the generation space of the SM particles, are promising. They can serve as an explanation for the quark and lepton mass hierarchies as well as for the different mixings in the quark and lepton sectors. In addition, flavor symmetries are significantly involved in the Higgs sector and predict certain forms of mass matrices. This high predictivity makes GUTs and flavor symmetries interesting for both, theorists and experimentalists. These extensions of the SM can be also combined with theories such as supersymmetry or extra dimensions. In addition, they usually have implications on the observed matter-antimatter asymmetry of the universe or can provide a dark matter candidate. In general, they also predict the lepton flavor violating rare decays {mu} {yields} e{gamma}, {tau} {yields} {mu}{gamma}, and {tau} {yields} e{gamma} which are strongly bounded by experiments but might be observed in the future. In this thesis, we combine all of these approaches, i.e., GUTs, the seesaw mechanism and flavor symmetries. Moreover, our request is to develop and perform a systematic model building approach with flavor symmetries and

  14. Systematic comparison of model polymer nanocomposite mechanics.

    Science.gov (United States)

    Xiao, Senbo; Peter, Christine; Kremer, Kurt

    2016-09-13

    Polymer nanocomposites render a range of outstanding materials from natural products such as silk, sea shells and bones, to synthesized nanoclay or carbon nanotube reinforced polymer systems. In contrast to the fast expanding interest in this type of material, the fundamental mechanisms of their mixing, phase behavior and reinforcement, especially for higher nanoparticle content as relevant for bio-inorganic composites, are still not fully understood. Although polymer nanocomposites exhibit diverse morphologies, qualitatively their mechanical properties are believed to be governed by a few parameters, namely their internal polymer network topology, nanoparticle volume fraction, particle surface properties and so on. Relating material mechanics to such elementary parameters is the purpose of this work. By taking a coarse-grained molecular modeling approach, we study an range of different polymer nanocomposites. We vary polymer nanoparticle connectivity, surface geometry and volume fraction to systematically study rheological/mechanical properties. Our models cover different materials, and reproduce key characteristics of real nanocomposites, such as phase separation, mechanical reinforcement. The results shed light on establishing elementary structure, property and function relationship of polymer nanocomposites.

  15. Systematic simulations of modified gravity: chameleon models

    Energy Technology Data Exchange (ETDEWEB)

    Brax, Philippe [Institut de Physique Theorique, CEA, IPhT, CNRS, URA 2306, F-91191Gif/Yvette Cedex (France); Davis, Anne-Christine [DAMTP, Centre for Mathematical Sciences, University of Cambridge, Wilberforce Road, Cambridge CB3 0WA (United Kingdom); Li, Baojiu [Institute for Computational Cosmology, Department of Physics, Durham University, Durham DH1 3LE (United Kingdom); Winther, Hans A. [Institute of Theoretical Astrophysics, University of Oslo, 0315 Oslo (Norway); Zhao, Gong-Bo, E-mail: philippe.brax@cea.fr, E-mail: a.c.davis@damtp.cam.ac.uk, E-mail: baojiu.li@durham.ac.uk, E-mail: h.a.winther@astro.uio.no, E-mail: gong-bo.zhao@port.ac.uk [Institute of Cosmology and Gravitation, University of Portsmouth, Portsmouth PO1 3FX (United Kingdom)

    2013-04-01

    In this work we systematically study the linear and nonlinear structure formation in chameleon theories of modified gravity, using a generic parameterisation which describes a large class of models using only 4 parameters. For this we have modified the N-body simulation code ecosmog to perform a total of 65 simulations for different models and parameter values, including the default ΛCDM. These simulations enable us to explore a significant portion of the parameter space. We have studied the effects of modified gravity on the matter power spectrum and mass function, and found a rich and interesting phenomenology where the difference with the ΛCDM paradigm cannot be reproduced by a linear analysis even on scales as large as k ∼ 0.05 hMpc{sup −1}, since the latter incorrectly assumes that the modification of gravity depends only on the background matter density. Our results show that the chameleon screening mechanism is significantly more efficient than other mechanisms such as the dilaton and symmetron, especially in high-density regions and at early times, and can serve as a guidance to determine the parts of the chameleon parameter space which are cosmologically interesting and thus merit further studies in the future.

  16. Systematic simulations of modified gravity: chameleon models

    International Nuclear Information System (INIS)

    Brax, Philippe; Davis, Anne-Christine; Li, Baojiu; Winther, Hans A.; Zhao, Gong-Bo

    2013-01-01

    In this work we systematically study the linear and nonlinear structure formation in chameleon theories of modified gravity, using a generic parameterisation which describes a large class of models using only 4 parameters. For this we have modified the N-body simulation code ecosmog to perform a total of 65 simulations for different models and parameter values, including the default ΛCDM. These simulations enable us to explore a significant portion of the parameter space. We have studied the effects of modified gravity on the matter power spectrum and mass function, and found a rich and interesting phenomenology where the difference with the ΛCDM paradigm cannot be reproduced by a linear analysis even on scales as large as k ∼ 0.05 hMpc −1 , since the latter incorrectly assumes that the modification of gravity depends only on the background matter density. Our results show that the chameleon screening mechanism is significantly more efficient than other mechanisms such as the dilaton and symmetron, especially in high-density regions and at early times, and can serve as a guidance to determine the parts of the chameleon parameter space which are cosmologically interesting and thus merit further studies in the future

  17. Underestimation of risk due to exposure misclassification

    DEFF Research Database (Denmark)

    Grandjean, Philippe; Budtz-Jørgensen, Esben; Keiding, Niels

    2004-01-01

    Exposure misclassification constitutes a major obstacle when developing dose-response relationships for risk assessment. A non-differentional error results in underestimation of the risk. If the degree of misclassification is known, adjustment may be achieved by sensitivity analysis. The purpose...... of this study was to examine the full magnitude of measurement error in determining the prenatal exposure to methylmercury. We used data from a prospective study of a Faroese birth cohort. Two biomarkers of methylmercury exposure were available, i.e., the mercury concentrations in cord blood and in maternal....... These findings illustrate that measurement error may be greatly underestimated if judged solely from reproducibility or laboratory quality data. Adjustment by sensitivity analysis is meaningful only if realistic measurement errors are applied. When exposure measurement errors are overlooked or underestimated...

  18. Mechanism for underestimation of isotopically determined glucose disposal

    International Nuclear Information System (INIS)

    Yki-Jaervinen, H.C.; Consoli, A.; Nurjhan, N.; Young, A.A.; Gerich, J.E.

    1989-01-01

    Use of [3H]glucose and a one-compartment model to determine glucose kinetics frequently underestimates the rate of glucose production (Ra). To assess to what extent an isotope effect, a tracer contaminant, or inadequacy of the model was responsible, we measured glucose Ra and forearm clearance of tracer and unlabeled glucose at various concentrations of plasma insulin (approximately 50, approximately 160, and approximately 1800 microU/ml) and plasma glucose (approximately 90, approximately 160, approximately 250, and approximately 400 mg/dl) under steady-state and non-steady-state conditions. Under isotopic steady-state conditions, the clearances of tracer and unlabeled glucose across the forearm were identical, and exogenous glucose infusion rates did not differ significantly from the isotopically determined glucose Ra (10.0 +/- 1.3 vs. 10.5 +/- 1.0 mg.kg-1 fat-free mass.min-1, respectively). However, under isotopic non-steady-state conditions, the isotopically determined Ra was significantly lower than the glucose infusion rate (11.5 +/- 1.3 vs. 13.7 +/- 1.5 mg.kg-1 fat-free mass.min-1, respectively, P less than .001), and the underestimation was related to the deviation from the isotopic steady state. When [3H]glucose specific activity of plasma samples from experiments with the greatest underestimation of Ra was determined by high-performance liquid chromatography, less than 7% of the underestimation could be accounted for by a contaminant. These results indicate that inadequacy of the one-compartment model is responsible for underestimation of glucose Ra under non-steady-state conditions and that there is no detectable isotopic effect or appreciable contaminant of [3-3H]glucose. We conclude that under isotopic steady-state conditions, [3-3H]glucose is a reliable tracer for glucose kinetic studies in humans

  19. Systematic identification of crystallization kinetics within a generic modelling framework

    DEFF Research Database (Denmark)

    Abdul Samad, Noor Asma Fazli Bin; Meisler, Kresten Troelstrup; Gernaey, Krist

    2012-01-01

    A systematic development of constitutive models within a generic modelling framework has been developed for use in design, analysis and simulation of crystallization operations. The framework contains a tool for model identification connected with a generic crystallizer modelling tool-box, a tool...

  20. Systematic effects in CALOR simulation code to model experimental configurations

    International Nuclear Information System (INIS)

    Job, P.K.; Proudfoot, J.; Handler, T.

    1991-01-01

    CALOR89 code system is being used to simulate test beam results and the design parameters of several calorimeter configurations. It has been bench-marked against the ZEUS, Dθ and HELIOS data. This study identifies the systematic effects in CALOR simulation to model the experimental configurations. Five major systematic effects are identified. These are the choice of high energy nuclear collision model, material composition, scintillator saturation, shower integration time, and the shower containment. Quantitative estimates of these systematic effects are presented. 23 refs., 6 figs., 7 tabs

  1. Conceptual Model for Systematic Construction Waste Management

    OpenAIRE

    Abd Rahim Mohd Hilmi Izwan; Kasim Narimah

    2017-01-01

    Development of the construction industry generated construction waste which can contribute towards environmental issues. Weaknesses of compliance in construction waste management especially in construction site have also contributed to the big issues of waste generated in landfills and illegal dumping area. This gives sign that construction projects are needed a systematic construction waste management. To date, a comprehensive criteria of construction waste management, particularly for const...

  2. Simulation models in population breast cancer screening : A systematic review

    NARCIS (Netherlands)

    Koleva-Kolarova, Rositsa G; Zhan, Zhuozhao; Greuter, Marcel J W; Feenstra, Talitha L; De Bock, Geertruida H

    The aim of this review was to critically evaluate published simulation models for breast cancer screening of the general population and provide a direction for future modeling. A systematic literature search was performed to identify simulation models with more than one application. A framework for

  3. Systematic reviews of animal models: methodology versus epistemology.

    Science.gov (United States)

    Greek, Ray; Menache, Andre

    2013-01-01

    Systematic reviews are currently favored methods of evaluating research in order to reach conclusions regarding medical practice. The need for such reviews is necessitated by the fact that no research is perfect and experts are prone to bias. By combining many studies that fulfill specific criteria, one hopes that the strengths can be multiplied and thus reliable conclusions attained. Potential flaws in this process include the assumptions that underlie the research under examination. If the assumptions, or axioms, upon which the research studies are based, are untenable either scientifically or logically, then the results must be highly suspect regardless of the otherwise high quality of the studies or the systematic reviews. We outline recent criticisms of animal-based research, namely that animal models are failing to predict human responses. It is this failure that is purportedly being corrected via systematic reviews. We then examine the assumption that animal models can predict human outcomes to perturbations such as disease or drugs, even under the best of circumstances. We examine the use of animal models in light of empirical evidence comparing human outcomes to those from animal models, complexity theory, and evolutionary biology. We conclude that even if legitimate criticisms of animal models were addressed, through standardization of protocols and systematic reviews, the animal model would still fail as a predictive modality for human response to drugs and disease. Therefore, systematic reviews and meta-analyses of animal-based research are poor tools for attempting to reach conclusions regarding human interventions.

  4. Poverty Underestimation in Rural India- A Critique

    OpenAIRE

    Sivakumar, Marimuthu; Sarvalingam, A

    2010-01-01

    When ever the Planning Commission of India releases the poverty data, that data is being criticised by experts and economists. The main criticism is underestimation of poverty especially in rural India by the Planning Commission. This paper focuses on that criticism and compares the Indian Planning Commission’s 2004-05 rural poverty data with the India’s 2400 kcal poverty norms, World Bank’s US $1.08 poverty concept and Asian Development Bank’s US $1.35 poverty concept.

  5. A Unified Framework for Systematic Model Improvement

    DEFF Research Database (Denmark)

    Kristensen, Niels Rode; Madsen, Henrik; Jørgensen, Sten Bay

    2003-01-01

    A unified framework for improving the quality of continuous time models of dynamic systems based on experimental data is presented. The framework is based on an interplay between stochastic differential equation (SDE) modelling, statistical tests and multivariate nonparametric regression...

  6. Systematic experimental based modeling of a rotary piezoelectric ultrasonic motor

    DEFF Research Database (Denmark)

    Mojallali, Hamed; Amini, Rouzbeh; Izadi-Zamanabadi, Roozbeh

    2007-01-01

    In this paper, a new method for equivalent circuit modeling of a traveling wave ultrasonic motor is presented. The free stator of the motor is modeled by an equivalent circuit containing complex circuit elements. A systematic approach for identifying the elements of the equivalent circuit is sugg...

  7. Models as instruments for optimizing hospital processes: a systematic review

    NARCIS (Netherlands)

    van Sambeek, J. R. C.; Cornelissen, F. A.; Bakker, P. J. M.; Krabbendam, J. J.

    2010-01-01

    PURPOSE: The purpose of this article is to find decision-making models for the design and control of processes regarding patient flows, considering various problem types, and to find out how usable these models are for managerial decision making. DESIGN/METHODOLOGY/APPROACH: A systematic review of

  8. A Systematic Identification Method for Thermodynamic Property Modelling

    DEFF Research Database (Denmark)

    Ana Perederic, Olivia; Cunico, Larissa; Sarup, Bent

    2017-01-01

    In this work, a systematic identification method for thermodynamic property modelling is proposed. The aim of the method is to improve the quality of phase equilibria prediction by group contribution based property prediction models. The method is applied to lipid systems where the Original UNIFAC...

  9. Models as instruments for optimizing hospital processes: a systematic review.

    Science.gov (United States)

    van Sambeek, J R C; Cornelissen, F A; Bakker, P J M; Krabbendam, J J

    2010-01-01

    The purpose of this article is to find decision-making models for the design and control of processes regarding patient flows, considering various problem types, and to find out how usable these models are for managerial decision making. A systematic review of the literature was carried out. Relevant literature from three databases was selected based on inclusion and exclusion criteria and the results were analyzed. A total of 68 articles were selected. Of these, 31 contained computer simulation models, ten contained descriptive models, and 27 contained analytical models. The review showed that descriptive models are only applied to process design problems, and that analytical and computer simulation models are applied to all types of problems to approximately the same extent. Only a few models have been validated in practice, and it seems that most models are not used for their intended purpose: to support management in decision making. The comparability of the relevant databases appears to be limited and there is an insufficient number of suitable keywords and MeSH headings, which makes searching systematically within the broad field of health care management relatively hard to accomplish. The findings give managers insight into the characteristics of various types of decision-support models and into the kinds of situations in which they are used. This is the first time literature on various kinds of models for supporting managerial decision making in hospitals has been systematically collected and assessed.

  10. Fatigue - an underestimated symptom in psoriatic arthritis.

    Science.gov (United States)

    Krajewska-Włodarczyk, Magdalena; Owczarczyk-Saczonek, Agnieszka; Placek, Waldemar

    2017-01-01

    The nature of fatigue is very complex and involves physiological, psychological and social phenomena at the same time, and the mechanisms leading to occurrence and severity of fatigue are still poorly understood. The condition of chronic inflammation associated with psoriatic arthritis can be regarded as a potential factor affecting development of fatigue. Only a few studies so far have focused on the occurrence of fatigue in psoriatic arthritis. The problem of chronic fatigue is underestimated in everyday clinical practice. Identification and analysis of subjective fatigue components in each patient can provide an objective basis for optimal fatigue treatment in daily practice. This review presents a definition of chronic fatigue and describes mechanisms that may be associated with development of fatigue, highlighting the role of chronic inflammation, selected fatigue measurement methods and relations of fatigue occurrence with clinical aspects of psoriatic arthritis.

  11. Fishermen´s underestimation of risk

    DEFF Research Database (Denmark)

    Knudsen, Fabienne; Grøn, Sisse

    2009-01-01

      Fishermen's underestimation of risk   Background: In order to understand the effect of footwear and flooring on slips, trips and falls, 1st author visited 4 fishing boats.  An important spinoff of the study was to get an in situ insight in the way, fishermen perceive risk.   Objectives......: The presentation will analyse fishermen's risk perception, its causes and consequences.   Methods: The first author participated in 3 voyages at sea on fishing vessels (from 1 to 10 days each and from 2 to 4 crewmembers) where  interviews and participant observation was undertaken. A 4th fishing boat was visited...... on dock and the crew interviewed. Based on notes, diary, interviews and photo/video documentation, records related to the fishermen's risk perception were compiled, and then analysed by means of theories of risk perception.   Results: Fishermen tend partly to underrate the risks they are running, partly...

  12. [Pica during pregnancy: a frequently underestimated problem].

    Science.gov (United States)

    López, Laura Beatriz; Ortega Soler, Carlos Rafael; de Portela, María Luz Pita Martín

    2004-03-01

    Pica is the compulsive intake of non-nutritive substances such as earth, clay, chalk, soap and ice. The most common forms of pica are geophagia or the intake of earth and pagophagia or the intake of ice. The description of this peculiar phenomenon dates back to the Greco-Roman civilization. Its prevalence during pregnancy is generally underestimated. Published data reveal a prevalence of between 8% and 65%. Investigations from Latin America indicate a prevalence of 23% to 44%. It is not clear yet which are the causes that predispose to pica, but they are frequently associated with anemia or iron deficiency during pregnancy. Its diagnosis, which only consists in questioning pregnant women, is generally omitted during prenatal care, probably because health professionals have no knowledge about this disorder. The identification of pica in pregnant women could contribute to the detection of a risk group where it is necessary to implement strategies as regards both the evaluation and the nutritional education.

  13. Systematic Methods and Tools for Computer Aided Modelling

    DEFF Research Database (Denmark)

    Fedorova, Marina

    Models are playing important roles in design and analysis of chemicals/bio-chemicals based products and the processes that manufacture them. Model-based methods and tools have the potential to decrease the number of experiments, which can be expensive and time consuming, and point to candidates......, where the experimental effort could be focused. In this project a general modelling framework for systematic model building through modelling templates, which supports the reuse of existing models via its new model import and export capabilities, have been developed. The new feature for model transfer...... has been developed by establishing a connection with an external modelling environment for code generation. The main contribution of this thesis is a creation of modelling templates and their connection with other modelling tools within a modelling framework. The goal was to create a user...

  14. Prediction models in women with postmenopausal bleeding: a systematic review

    NARCIS (Netherlands)

    van Hanegem, Nehalennia; Breijer, Maria C.; Opmeer, Brent C.; Mol, Ben W. J.; Timmermans, Anne

    2012-01-01

    Postmenopausal bleeding is associated with an elevated risk of having endometrial cancer. The aim of this review is to give an overview of existing prediction models on endometrial cancer in women with postmenopausal bleeding. In a systematic search of the literature, we identified nine prognostic

  15. The Social Relations Model in Family Studies: A Systematic Review

    Science.gov (United States)

    Eichelsheim, Veroni I.; Dekovic, Maja; Buist, Kirsten L.; Cook, William L.

    2009-01-01

    The Social Relations Model (SRM) allows for examination of family relations on three different levels: the individual level (actor and partner effects), the dyadic level (relationship effects), and the family level (family effect). The aim of this study was to present a systematic review of SRM family studies and identify general patterns in the…

  16. Hospitality and Tourism Online Review Research: A Systematic Analysis and Heuristic-Systematic Model

    Directory of Open Access Journals (Sweden)

    Sunyoung Hlee

    2018-04-01

    Full Text Available With tremendous growth and potential of online consumer reviews, online reviews of hospitality and tourism are now playing a significant role in consumer attitude and buying behaviors. This study reviewed and analyzed hospitality and tourism related articles published in academic journals. The systematic approach was used to analyze 55 research articles between January 2008 and December 2017. This study presented a brief synthesis of research by investigating content-related characteristics of hospitality and tourism online reviews (HTORs in different market segments. Two research questions were addressed. Building upon our literature analysis, we used the heuristic-systematic model (HSM to summarize and classify the characteristics affecting consumer perception in previous HTOR studies. We believe that the framework helps researchers to identify the research topic in extended HTORs literature and to point out possible direction for future studies.

  17. Maxillofacial trauma - Underestimation of cervical spine injury.

    Science.gov (United States)

    Reich, Waldemar; Surov, Alexey; Eckert, Alexander Walter

    2016-09-01

    Undiagnosed cervical spine injury can have devastating results. The aim of this study was to analyse patients with primary maxillofacial trauma and a concomitant cervical spine injury. It is hypothetised that cervical spine injury is predictable in maxillofacial surgery. A monocentric clinical study was conducted over a 10-year period to analyse patients with primary maxillofacial and associated cervical spine injuries. Demographic data, mechanism of injury, specific trauma and treatments provided were reviewed. Additionally a search of relevant international literature was conducted in PubMed by terms "maxillofacial" AND "cervical spine" AND "injury". Of 3956 patients, n = 3732 (94.3%) suffered from craniomaxillofacial injuries only, n = 174 (4.4%) from cervical spine injuries only, and n = 50 (1.3%) from both craniomaxillofacial and cervical spine injuries. In this study cohort the most prevalent craniofacial injuries were: n = 41 (44%) midfacial and n = 21 (22.6%) skull base fractures. Cervical spine injuries primarily affected the upper cervical spine column: n = 39 (58.2%) vs. n = 28 (41.8%). Only in 3 of 50 cases (6%), the cervical spine injury was diagnosed coincidentally, and the cervical spine column was under immobilised. The operative treatment rate for maxillofacial injuries was 36% (n = 18), and for cervical spine injuries 20% (n = 10). The overall mortality rate was 8% (n = 4). The literature search yielded only 12 papers (11 retrospective and monocentric cohort studies) and is discussed before our own results. In cases of apparently isolated maxillofacial trauma, maxillofacial surgeons should be aware of a low but serious risk of underestimating an unstable cervical spine injury. Copyright © 2016 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

  18. Business model framework applications in health care: A systematic review.

    Science.gov (United States)

    Fredriksson, Jens Jacob; Mazzocato, Pamela; Muhammed, Rafiq; Savage, Carl

    2017-11-01

    It has proven to be a challenge for health care organizations to achieve the Triple Aim. In the business literature, business model frameworks have been used to understand how organizations are aligned to achieve their goals. We conducted a systematic literature review with an explanatory synthesis approach to understand how business model frameworks have been applied in health care. We found a large increase in applications of business model frameworks during the last decade. E-health was the most common context of application. We identified six applications of business model frameworks: business model description, financial assessment, classification based on pre-defined typologies, business model analysis, development, and evaluation. Our synthesis suggests that the choice of business model framework and constituent elements should be informed by the intent and context of application. We see a need for harmonization in the choice of elements in order to increase generalizability, simplify application, and help organizations realize the Triple Aim.

  19. The underestimated potential of solar energy to mitigate climate change

    Science.gov (United States)

    Creutzig, Felix; Agoston, Peter; Goldschmidt, Jan Christoph; Luderer, Gunnar; Nemet, Gregory; Pietzcker, Robert C.

    2017-09-01

    The Intergovernmental Panel on Climate Change's fifth assessment report emphasizes the importance of bioenergy and carbon capture and storage for achieving climate goals, but it does not identify solar energy as a strategically important technology option. That is surprising given the strong growth, large resource, and low environmental footprint of photovoltaics (PV). Here we explore how models have consistently underestimated PV deployment and identify the reasons for underlying bias in models. Our analysis reveals that rapid technological learning and technology-specific policy support were crucial to PV deployment in the past, but that future success will depend on adequate financing instruments and the management of system integration. We propose that with coordinated advances in multiple components of the energy system, PV could supply 30-50% of electricity in competitive markets.

  20. Simulation models in population breast cancer screening: A systematic review.

    Science.gov (United States)

    Koleva-Kolarova, Rositsa G; Zhan, Zhuozhao; Greuter, Marcel J W; Feenstra, Talitha L; De Bock, Geertruida H

    2015-08-01

    The aim of this review was to critically evaluate published simulation models for breast cancer screening of the general population and provide a direction for future modeling. A systematic literature search was performed to identify simulation models with more than one application. A framework for qualitative assessment which incorporated model type; input parameters; modeling approach, transparency of input data sources/assumptions, sensitivity analyses and risk of bias; validation, and outcomes was developed. Predicted mortality reduction (MR) and cost-effectiveness (CE) were compared to estimates from meta-analyses of randomized control trials (RCTs) and acceptability thresholds. Seven original simulation models were distinguished, all sharing common input parameters. The modeling approach was based on tumor progression (except one model) with internal and cross validation of the resulting models, but without any external validation. Differences in lead times for invasive or non-invasive tumors, and the option for cancers not to progress were not explicitly modeled. The models tended to overestimate the MR (11-24%) due to screening as compared to optimal RCTs 10% (95% CI - 2-21%) MR. Only recently, potential harms due to regular breast cancer screening were reported. Most scenarios resulted in acceptable cost-effectiveness estimates given current thresholds. The selected models have been repeatedly applied in various settings to inform decision making and the critical analysis revealed high risk of bias in their outcomes. Given the importance of the models, there is a need for externally validated models which use systematical evidence for input data to allow for more critical evaluation of breast cancer screening. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Systematic reduction of a detailed atrial myocyte model

    Science.gov (United States)

    Lombardo, Daniel M.; Rappel, Wouter-Jan

    2017-09-01

    Cardiac arrhythmias are a major health concern and often involve poorly understood mechanisms. Mathematical modeling is able to provide insights into these mechanisms which might result in better treatment options. A key element of this modeling is a description of the electrophysiological properties of cardiac cells. A number of electrophysiological models have been developed, ranging from highly detailed and complex models, containing numerous parameters and variables, to simplified models in which variables and parameters no longer directly correspond to electrophysiological quantities. In this study, we present a systematic reduction of the complexity of the detailed model of Koivumaki et al. using the recently developed manifold boundary approximation method. We reduce the original model, containing 42 variables and 37 parameters, to a model with only 11 variables and 5 parameters and show that this reduced model can accurately reproduce the action potential shape and restitution curve of the original model. The reduced model contains only five currents and all variables and parameters can be directly linked to electrophysiological quantities. Due to its reduction in complexity, simulation times of our model are decreased more than three-fold. Furthermore, fitting the reduced model to clinical data is much more efficient, a potentially important step towards patient-specific modeling.

  2. The underestimation of egocentric distance: evidence from frontal matching tasks

    Science.gov (United States)

    Li, Zhi; Phillips, John

    2011-01-01

    There is controversy over the existence, nature, and cause of error in egocentric distance judgments. One proposal is that the systematic biases often found in explicit judgments of egocentric distance along the ground may be related to recently observed biases in the perceived declination of gaze (Durgin & Li, Attention, Perception, & Psychophysics, in press), To measure perceived egocentric distance nonverbally, observers in a field were asked to position themselves so that their distance from one of two experimenters was equal to the frontal distance between the experimenters. Observers placed themselves too far away, consistent with egocentric distance underestimation. A similar experiment was conducted with vertical frontal extents. Both experiments were replicated in panoramic virtual reality. Perceived egocentric distance was quantitatively consistent with angular bias in perceived gaze declination (1.5 gain). Finally, an exocentric distance-matching task was contrasted with a variant of the egocentric matching task. The egocentric matching data approximate a constant compression of perceived egocentric distance with a power function exponent of nearly 1; exocentric matches had an exponent of about 0.67. The divergent pattern between egocentric and exocentric matches suggests that they depend on different visual cues. PMID:21735313

  3. Phosphate Kinetic Models in Hemodialysis: A Systematic Review.

    Science.gov (United States)

    Laursen, Sisse H; Vestergaard, Peter; Hejlesen, Ole K

    2018-01-01

    Understanding phosphate kinetics in dialysis patients is important for the prevention of hyperphosphatemia and related complications. One approach to gain new insights into phosphate behavior is physiologic modeling. Various models that describe and quantify intra- and/or interdialytic phosphate kinetics have been proposed, but there is a dearth of comprehensive comparisons of the available models. The objective of this analysis was to provide a systematic review of existing published models of phosphate metabolism in the setting of maintenance hemodialysis therapy. Systematic review. Hemodialysis patients. Studies published in peer-reviewed journals in English about phosphate kinetic modeling in the setting of hemodialysis therapy. Modeling equations from specific reviewed studies. Changes in plasma phosphate or serum phosphate concentrations. Of 1,964 nonduplicate studies evaluated, 11 were included, comprising 9 different phosphate models with 1-, 2-, 3-, or 4-compartment assumptions. Between 2 and 11 model parameters were included in the models studied. Quality scores of the studies using the Newcastle-Ottawa Scale ranged from 2 to 11 (scale, 0-14). 2 studies were considered low quality, 6 were considered medium quality, and 3 were considered high quality. Only English-language studies were included. Many parameters known to influence phosphate balance are not included in existing phosphate models that do not fully reflect the physiology of phosphate metabolism in the setting of hemodialysis. Moreover, models have not been sufficiently validated for their use as a tool to simulate phosphate kinetics in hemodialysis therapy. Copyright © 2017 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

  4. A systematic review of current osteoporotic metaphyseal fracture animal models.

    Science.gov (United States)

    Wong, R M Y; Choy, M H V; Li, M C M; Leung, K-S; K-H Chow, S; Cheung, W-H; Cheng, J C Y

    2018-01-01

    The treatment of osteoporotic fractures is a major challenge, and the enhancement of healing is critical as a major goal in modern fracture management. Most osteoporotic fractures occur at the metaphyseal bone region but few models exist and the healing is still poorly understood. A systematic review was conducted to identify and analyse the appropriateness of current osteoporotic metaphyseal fracture animal models. A literature search was performed on the Pubmed, Embase, and Web of Science databases, and relevant articles were selected. A total of 19 studies were included. Information on the animal, induction of osteoporosis, fracture technique, site and fixation, healing results, and utility of the model were extracted. Fracture techniques included drill hole defects (3 of 19), bone defects (3 of 19), partial osteotomy (1 of 19), and complete osteotomies (12 of 19). Drill hole models and incomplete osteotomy models are easy to perform and allow the study of therapeutic agents but do not represent the usual clinical setting. Additionally, biomaterials can be filled into drill hole defects for analysis. Complete osteotomy models are most commonly used and are best suited for the investigation of therapeutic drugs or noninvasive interventions. The metaphyseal defect models allow the study of biomaterials, which are associated with complex and comminuted osteoporotic fractures. For a clinically relevant model, we propose that an animal model should satisfy the following criteria to study osteoporotic fracture healing: 1) induction of osteoporosis, 2) complete osteotomy or defect at the metaphysis unilaterally, and 3) internal fixation. Cite this article : R. M. Y. Wong, M. H. V. Choy, M. C. M. Li, K-S. Leung, S. K-H. Chow, W-H. Cheung, J. C. Y. Cheng. A systematic review of current osteoporotic metaphyseal fracture animal models. Bone Joint Res 2018;7:6-11. DOI: 10.1302/2046-3758.71.BJR-2016-0334.R2. © 2018 Wong et al.

  5. Systematic integration of experimental data and models in systems biology.

    Science.gov (United States)

    Li, Peter; Dada, Joseph O; Jameson, Daniel; Spasic, Irena; Swainston, Neil; Carroll, Kathleen; Dunn, Warwick; Khan, Farid; Malys, Naglis; Messiha, Hanan L; Simeonidis, Evangelos; Weichart, Dieter; Winder, Catherine; Wishart, Jill; Broomhead, David S; Goble, Carole A; Gaskell, Simon J; Kell, Douglas B; Westerhoff, Hans V; Mendes, Pedro; Paton, Norman W

    2010-11-29

    The behaviour of biological systems can be deduced from their mathematical models. However, multiple sources of data in diverse forms are required in the construction of a model in order to define its components and their biochemical reactions, and corresponding parameters. Automating the assembly and use of systems biology models is dependent upon data integration processes involving the interoperation of data and analytical resources. Taverna workflows have been developed for the automated assembly of quantitative parameterised metabolic networks in the Systems Biology Markup Language (SBML). A SBML model is built in a systematic fashion by the workflows which starts with the construction of a qualitative network using data from a MIRIAM-compliant genome-scale model of yeast metabolism. This is followed by parameterisation of the SBML model with experimental data from two repositories, the SABIO-RK enzyme kinetics database and a database of quantitative experimental results. The models are then calibrated and simulated in workflows that call out to COPASIWS, the web service interface to the COPASI software application for analysing biochemical networks. These systems biology workflows were evaluated for their ability to construct a parameterised model of yeast glycolysis. Distributed information about metabolic reactions that have been described to MIRIAM standards enables the automated assembly of quantitative systems biology models of metabolic networks based on user-defined criteria. Such data integration processes can be implemented as Taverna workflows to provide a rapid overview of the components and their relationships within a biochemical system.

  6. Systematic evaluation of atmospheric chemistry-transport model CHIMERE

    Science.gov (United States)

    Khvorostyanov, Dmitry; Menut, Laurent; Mailler, Sylvain; Siour, Guillaume; Couvidat, Florian; Bessagnet, Bertrand; Turquety, Solene

    2017-04-01

    Regional-scale atmospheric chemistry-transport models (CTM) are used to develop air quality regulatory measures, to support environmentally sensitive decisions in the industry, and to address variety of scientific questions involving the atmospheric composition. Model performance evaluation with measurement data is critical to understand their limits and the degree of confidence in model results. CHIMERE CTM (http://www.lmd.polytechnique.fr/chimere/) is a French national tool for operational forecast and decision support and is widely used in the international research community in various areas of atmospheric chemistry and physics, climate, and environment (http://www.lmd.polytechnique.fr/chimere/CW-articles.php). This work presents the model evaluation framework applied systematically to the new CHIMERE CTM versions in the course of the continuous model development. The framework uses three of the four CTM evaluation types identified by the Environmental Protection Agency (EPA) and the American Meteorological Society (AMS): operational, diagnostic, and dynamic. It allows to compare the overall model performance in subsequent model versions (operational evaluation), identify specific processes and/or model inputs that could be improved (diagnostic evaluation), and test the model sensitivity to the changes in air quality, such as emission reductions and meteorological events (dynamic evaluation). The observation datasets currently used for the evaluation are: EMEP (surface concentrations), AERONET (optical depths), and WOUDC (ozone sounding profiles). The framework is implemented as an automated processing chain and allows interactive exploration of the results via a web interface.

  7. Models Predicting Success of Infertility Treatment: A Systematic Review

    Science.gov (United States)

    Zarinara, Alireza; Zeraati, Hojjat; Kamali, Koorosh; Mohammad, Kazem; Shahnazari, Parisa; Akhondi, Mohammad Mehdi

    2016-01-01

    Background: Infertile couples are faced with problems that affect their marital life. Infertility treatment is expensive and time consuming and occasionally isn’t simply possible. Prediction models for infertility treatment have been proposed and prediction of treatment success is a new field in infertility treatment. Because prediction of treatment success is a new need for infertile couples, this paper reviewed previous studies for catching a general concept in applicability of the models. Methods: This study was conducted as a systematic review at Avicenna Research Institute in 2015. Six data bases were searched based on WHO definitions and MESH key words. Papers about prediction models in infertility were evaluated. Results: Eighty one papers were eligible for the study. Papers covered years after 1986 and studies were designed retrospectively and prospectively. IVF prediction models have more shares in papers. Most common predictors were age, duration of infertility, ovarian and tubal problems. Conclusion: Prediction model can be clinically applied if the model can be statistically evaluated and has a good validation for treatment success. To achieve better results, the physician and the couples’ needs estimation for treatment success rate were based on history, the examination and clinical tests. Models must be checked for theoretical approach and appropriate validation. The privileges for applying the prediction models are the decrease in the cost and time, avoiding painful treatment of patients, assessment of treatment approach for physicians and decision making for health managers. The selection of the approach for designing and using these models is inevitable. PMID:27141461

  8. Probabilistic modeling of systematic errors in two-hybrid experiments.

    Science.gov (United States)

    Sontag, David; Singh, Rohit; Berger, Bonnie

    2007-01-01

    We describe a novel probabilistic approach to estimating errors in two-hybrid (2H) experiments. Such experiments are frequently used to elucidate protein-protein interaction networks in a high-throughput fashion; however, a significant challenge with these is their relatively high error rate, specifically, a high false-positive rate. We describe a comprehensive error model for 2H data, accounting for both random and systematic errors. The latter arise from limitations of the 2H experimental protocol: in theory, the reporting mechanism of a 2H experiment should be activated if and only if the two proteins being tested truly interact; in practice, even in the absence of a true interaction, it may be activated by some proteins - either by themselves or through promiscuous interaction with other proteins. We describe a probabilistic relational model that explicitly models the above phenomenon and use Markov Chain Monte Carlo (MCMC) algorithms to compute both the probability of an observed 2H interaction being true as well as the probability of individual proteins being self-activating/promiscuous. This is the first approach that explicitly models systematic errors in protein-protein interaction data; in contrast, previous work on this topic has modeled errors as being independent and random. By explicitly modeling the sources of noise in 2H systems, we find that we are better able to make use of the available experimental data. In comparison with Bader et al.'s method for estimating confidence in 2H predicted interactions, the proposed method performed 5-10% better overall, and in particular regimes improved prediction accuracy by as much as 76%. http://theory.csail.mit.edu/probmod2H

  9. Did the Stern Review underestimate US and global climate damages?

    International Nuclear Information System (INIS)

    Ackerman, Frank; Stanton, Elizabeth A.; Hope, Chris; Alberth, Stephane

    2009-01-01

    The Stern Review received widespread attention for its innovative approach to the economics of climate change when it appeared in 2006, and generated controversies that have continued to this day. One key controversy concerns the magnitude of the expected impacts of climate change. Stern's estimates, based on results from the PAGE2002 model, sounded substantially greater than those produced by many other models, leading several critics to suggest that Stern had inflated his damage figures. We reached the opposite conclusion in a recent application of PAGE2002 in a study of the costs to the US economy of inaction on climate change. This article describes our revisions to the PAGE estimates, and explains our conclusion that the model runs used in the Stern Review may well underestimate US and global damages. Stern's estimates from PAGE2002 implied that mean business-as-usual damages in 2100 would represent just 0.4 percent of GDP for the United States and 2.2 percent of GDP for the world. Our revisions and reinterpretation of the PAGE model imply that climate damages in 2100 could reach 2.6 percent of GDP for the United States and 10.8 percent for the world.

  10. Coronary heart disease policy models: a systematic review

    Directory of Open Access Journals (Sweden)

    Capewell Simon

    2006-08-01

    Full Text Available Abstract Background The prevention and treatment of coronary heart disease (CHD is complex. A variety of models have therefore been developed to try and explain past trends and predict future possibilities. The aim of this systematic review was to evaluate the strengths and limitations of existing CHD policy models. Methods A search strategy was developed, piloted and run in MEDLINE and EMBASE electronic databases, supplemented by manually searching reference lists of relevant articles and reviews. Two reviewers independently checked the papers for inclusion and appraisal. All CHD modelling studies were included which addressed a defined population and reported on one or more key outcomes (deaths prevented, life years gained, mortality, incidence, prevalence, disability or cost of treatment. Results In total, 75 articles describing 42 models were included; 12 (29% of the 42 models were micro-simulation, 8 (19% cell-based, and 8 (19% life table analyses, while 14 (33% used other modelling methods. Outcomes most commonly reported were cost-effectiveness (36%, numbers of deaths prevented (33%, life-years gained (23% or CHD incidence (23%. Among the 42 models, 29 (69% included one or more risk factors for primary prevention, while 8 (19% just considered CHD treatments. Only 5 (12% were comprehensive, considering both risk factors and treatments. The six best-developed models are summarised in this paper, all are considered in detail in the appendices. Conclusion Existing CHD policy models vary widely in their depth, breadth, quality, utility and versatility. Few models have been calibrated against observed data, replicated in different settings or adequately validated. Before being accepted as a policy aid, any CHD model should provide an explicit statement of its aims, assumptions, outputs, strengths and limitations.

  11. Maturity Models in Supply Chain Sustainability: A Systematic Literature Review

    Directory of Open Access Journals (Sweden)

    Elisabete Correia

    2017-01-01

    Full Text Available A systematic literature review of supply chain maturity models with sustainability concerns is presented. The objective is to give insights into methodological issues related to maturity models, namely the research objectives; the research methods used to develop, validate and test them; the scope; and the main characteristics associated with their design. The literature review was performed based on journal articles and conference papers from 2000 to 2015 using the SCOPUS, Emerald Insight, EBSCO and Web of Science databases. Most of the analysed papers have as main objective the development of maturity models and their validation. The case study is the methodology that is most widely used by researchers to develop and validate maturity models. From the sustainability perspective, the scope of the analysed maturity models is the Triple Bottom Line (TBL and environmental dimension, focusing on a specific process (eco-design and new product development and without a broad SC perspective. The dominant characteristics associated with the design of the maturity models are the maturity grids and a continuous representation. In addition, results do not allow identifying a trend for a specific number of maturity levels. The comprehensive review, analysis, and synthesis of the maturity model literature represent an important contribution to the organization of this research area, making possible to clarify some confusion that exists about concepts, approaches and components of maturity models in sustainability. Various aspects associated with the maturity models (i.e., research objectives, research methods, scope and characteristics of the design of models are explored to contribute to the evolution and significance of this multidimensional area.

  12. A Systematic Literature Review of Agile Maturity Model Research

    Directory of Open Access Journals (Sweden)

    Vaughan Henriques

    2017-02-01

    Full Text Available Background/Aim/Purpose: A commonly implemented software process improvement framework is the capability maturity model integrated (CMMI. Existing literature indicates higher levels of CMMI maturity could result in a loss of agility due to its organizational focus. To maintain agility, research has focussed attention on agile maturity models. The objective of this paper is to find the common research themes and conclusions in agile maturity model research. Methodology: This research adopts a systematic approach to agile maturity model research, using Google Scholar, Science Direct, and IEEE Xplore as sources. In total 531 articles were initially found matching the search criteria, which was filtered to 39 articles by applying specific exclusion criteria. Contribution:: The article highlights the trends in agile maturity model research, specifically bringing to light the lack of research providing validation of such models. Findings: Two major themes emerge, being the coexistence of agile and CMMI and the development of agile principle based maturity models. The research trend indicates an increase in agile maturity model articles, particularly in the latter half of the last decade, with concentrations of research coinciding with version updates of CMMI. While there is general consensus around higher CMMI maturity levels being incompatible with true agility, there is evidence of the two coexisting when agile is introduced into already highly matured environments. Future Research:\tFuture research direction for this topic should include how to attain higher levels of CMMI maturity using only agile methods, how governance is addressed in agile environments, and whether existing agile maturity models relate to improved project success.

  13. Systematic approach to verification and validation: High explosive burn models

    Energy Technology Data Exchange (ETDEWEB)

    Menikoff, Ralph [Los Alamos National Laboratory; Scovel, Christina A. [Los Alamos National Laboratory

    2012-04-16

    , run a simulation, and generate a comparison plot showing simulated and experimental velocity gauge data. These scripts are then applied to several series of experiments and to several HE burn models. The same systematic approach is applicable to other types of material models; for example, equations of state models and material strength models.

  14. Systematic Analysis of Hollow Fiber Model of Tuberculosis Experiments.

    Science.gov (United States)

    Pasipanodya, Jotam G; Nuermberger, Eric; Romero, Klaus; Hanna, Debra; Gumbo, Tawanda

    2015-08-15

    The in vitro hollow fiber system model of tuberculosis (HFS-TB), in tandem with Monte Carlo experiments, was introduced more than a decade ago. Since then, it has been used to perform a large number of tuberculosis pharmacokinetics/pharmacodynamics (PK/PD) studies that have not been subjected to systematic analysis. We performed a literature search to identify all HFS-TB experiments published between 1 January 2000 and 31 December 2012. There was no exclusion of articles by language. Bias minimization was according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Steps for reporting systematic reviews were followed. There were 22 HFS-TB studies published, of which 12 were combination therapy studies and 10 were monotherapy studies. There were 4 stand-alone Monte Carlo experiments that utilized quantitative output from the HFS-TB. All experiments reported drug pharmacokinetics, which recapitulated those encountered in humans. HFS-TB studies included log-phase growth studies under ambient air, semidormant bacteria at pH 5.8, and nonreplicating persisters at low oxygen tension of ≤ 10 parts per billion. The studies identified antibiotic exposures associated with optimal kill of Mycobacterium tuberculosis and suppression of acquired drug resistance (ADR) and informed predictions about optimal clinical doses, expected performance of standard doses and regimens in patients, and expected rates of ADR, as well as a proposal of new susceptibility breakpoints. The HFS-TB model offers the ability to perform PK/PD studies including humanlike drug exposures, to identify bactericidal and sterilizing effect rates, and to identify exposures associated with suppression of drug resistance. Because of the ability to perform repetitive sampling from the same unit over time, the HFS-TB vastly improves statistical power and facilitates the execution of time-to-event analyses and repeated event analyses, as well as dynamic system pharmacology mathematical

  15. The Application of Adaptive Behaviour Models: A Systematic Review

    Directory of Open Access Journals (Sweden)

    Jessica A. Price

    2018-01-01

    Full Text Available Adaptive behaviour has been viewed broadly as an individual’s ability to meet the standards of social responsibilities and independence; however, this definition has been a source of debate amongst researchers and clinicians. Based on the rich history and the importance of the construct of adaptive behaviour, the current study aimed to provide a comprehensive overview of the application of adaptive behaviour models to assessment tools, through a systematic review. A plethora of assessment measures for adaptive behaviour have been developed in order to adequately assess the construct; however, it appears that the only definition on which authors seem to agree is that adaptive behaviour is what adaptive behaviour scales measure. The importance of the construct for diagnosis, intervention and planning has been highlighted throughout the literature. It is recommended that researchers and clinicians critically review what measures of adaptive behaviour they are utilising and it is suggested that the definition and theory is revisited.

  16. Systematic review of model-based cervical screening evaluations.

    Science.gov (United States)

    Mendes, Diana; Bains, Iren; Vanni, Tazio; Jit, Mark

    2015-05-01

    Optimising population-based cervical screening policies is becoming more complex due to the expanding range of screening technologies available and the interplay with vaccine-induced changes in epidemiology. Mathematical models are increasingly being applied to assess the impact of cervical cancer screening strategies. We systematically reviewed MEDLINE®, Embase, Web of Science®, EconLit, Health Economic Evaluation Database, and The Cochrane Library databases in order to identify the mathematical models of human papillomavirus (HPV) infection and cervical cancer progression used to assess the effectiveness and/or cost-effectiveness of cervical cancer screening strategies. Key model features and conclusions relevant to decision-making were extracted. We found 153 articles meeting our eligibility criteria published up to May 2013. Most studies (72/153) evaluated the introduction of a new screening technology, with particular focus on the comparison of HPV DNA testing and cytology (n = 58). Twenty-eight in forty of these analyses supported HPV DNA primary screening implementation. A few studies analysed more recent technologies - rapid HPV DNA testing (n = 3), HPV DNA self-sampling (n = 4), and genotyping (n = 1) - and were also supportive of their introduction. However, no study was found on emerging molecular markers and their potential utility in future screening programmes. Most evaluations (113/153) were based on models simulating aggregate groups of women at risk of cervical cancer over time without accounting for HPV infection transmission. Calibration to country-specific outcome data is becoming more common, but has not yet become standard practice. Models of cervical screening are increasingly used, and allow extrapolation of trial data to project the population-level health and economic impact of different screening policy. However, post-vaccination analyses have rarely incorporated transmission dynamics. Model calibration to country

  17. Testing flow diversion in animal models: a systematic review.

    Science.gov (United States)

    Fahed, Robert; Raymond, Jean; Ducroux, Célina; Gentric, Jean-Christophe; Salazkin, Igor; Ziegler, Daniela; Gevry, Guylaine; Darsaut, Tim E

    2016-04-01

    Flow diversion (FD) is increasingly used to treat intracranial aneurysms. We sought to systematically review published studies to assess the quality of reporting and summarize the results of FD in various animal models. Databases were searched to retrieve all animal studies on FD from 2000 to 2015. Extracted data included species and aneurysm models, aneurysm and neck dimensions, type of flow diverter, occlusion rates, and complications. Articles were evaluated using a checklist derived from the Animal Research: Reporting of In Vivo Experiments (ARRIVE) guidelines. Forty-two articles reporting the results of FD in nine different aneurysm models were included. The rabbit elastase-induced aneurysm model was the most commonly used, with 3-month occlusion rates of 73.5%, (95%CI [61.9-82.6%]). FD of surgical sidewall aneurysms, constructed in rabbits or canines, resulted in high occlusion rates (100% [65.5-100%]). FD resulted in modest occlusion rates (15.4% [8.9-25.1%]) when tested in six complex canine aneurysm models designed to reproduce more difficult clinical contexts (large necks, bifurcation, or fusiform aneurysms). Adverse events, including branch occlusion, were rarely reported. There were no hemorrhagic complications. Articles complied with 20.8 ± 3.9 of 41 ARRIVE items; only a small number used randomization (3/42 articles [7.1%]) or a control group (13/42 articles [30.9%]). Preclinical studies on FD have shown various results. Occlusion of elastase-induced aneurysms was common after FD. The model is not challenging but standardized in many laboratories. Failures of FD can be reproduced in less standardized but more challenging surgical canine constructions. The quality of reporting could be improved.

  18. Stem cells in animal asthma models: a systematic review.

    Science.gov (United States)

    Srour, Nadim; Thébaud, Bernard

    2014-12-01

    Asthma control frequently falls short of the goals set in international guidelines. Treatment options for patients with poorly controlled asthma despite inhaled corticosteroids and long-acting β-agonists are limited, and new therapeutic options are needed. Stem cell therapy is promising for a variety of disorders but there has been no human clinical trial of stem cell therapy for asthma. We aimed to systematically review the literature regarding the potential benefits of stem cell therapy in animal models of asthma to determine whether a human trial is warranted. The MEDLINE and Embase databases were searched for original studies of stem cell therapy in animal asthma models. Nineteen studies were selected. They were found to be heterogeneous in their design. Mesenchymal stromal cells were used before sensitization with an allergen, before challenge with the allergen and after challenge, most frequently with ovalbumin, and mainly in BALB/c mice. Stem cell therapy resulted in a reduction of bronchoalveolar lavage fluid inflammation and eosinophilia as well as Th2 cytokines such as interleukin-4 and interleukin-5. Improvement in histopathology such as peribronchial and perivascular inflammation, epithelial thickness, goblet cell hyperplasia and smooth muscle layer thickening was universal. Several studies showed a reduction in airway hyper-responsiveness. Stem cell therapy decreases eosinophilic and Th2 inflammation and is effective in several phases of the allergic response in animal asthma models. Further study is warranted, up to human clinical trials. Copyright © 2014 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

  19. Background model systematics for the Fermi GeV excess

    Energy Technology Data Exchange (ETDEWEB)

    Calore, Francesca; Cholis, Ilias; Weniger, Christoph

    2015-03-01

    The possible gamma-ray excess in the inner Galaxy and the Galactic center (GC) suggested by Fermi-LAT observations has triggered a large number of studies. It has been interpreted as a variety of different phenomena such as a signal from WIMP dark matter annihilation, gamma-ray emission from a population of millisecond pulsars, or emission from cosmic rays injected in a sequence of burst-like events or continuously at the GC. We present the first comprehensive study of model systematics coming from the Galactic diffuse emission in the inner part of our Galaxy and their impact on the inferred properties of the excess emission at Galactic latitudes 2° < |b| < 20° and 300 MeV to 500 GeV. We study both theoretical and empirical model systematics, which we deduce from a large range of Galactic diffuse emission models and a principal component analysis of residuals in numerous test regions along the Galactic plane. We show that the hypothesis of an extended spherical excess emission with a uniform energy spectrum is compatible with the Fermi-LAT data in our region of interest at 95% CL. Assuming that this excess is the extended counterpart of the one seen in the inner few degrees of the Galaxy, we derive a lower limit of 10.0° (95% CL) on its extension away from the GC. We show that, in light of the large correlated uncertainties that affect the subtraction of the Galactic diffuse emission in the relevant regions, the energy spectrum of the excess is equally compatible with both a simple broken power-law of break energy E(break) = 2.1 ± 0.2 GeV, and with spectra predicted by the self-annihilation of dark matter, implying in the case of bar bb final states a dark matter mass of m(χ)=49(+6.4)(-)(5.4)  GeV.

  20. Underestimation of hepatic glucose production by radioactive and stable tracers

    International Nuclear Information System (INIS)

    Argoud, G.M.; Schade, D.S.; Eaton, R.P.

    1987-01-01

    Although negative hepatic glucose production rates are physiologically impossible, they have been observed when hepatic glucose production is measured with the tracer-dilution technique during the hyperinsulinemic, euglycemic glucose clamp. Because hepatic glucose production is determined from the difference between tracer-derived glucose disposal and the known exogenous glucose infusion rate, the negative values for hepatic glucose production must result from an underestimation of glucose disposal by the tracer technique. In the current investigation, tracer-derived glucose disposal was measured in 25 subjects undergoing hyperinsulinemic, euglycemic clamps. Glucose disposal was measured with both radioactive and stable isotopes that utilize different methodologies, to determine whether discriminant metabolism of the isotopes versus methodological error leads to underestimation of tracer-derived glucose disposal. Both the radioactive and stable methodologies underestimated the exogenous glucose infusion rate during the hyperinsulinemic euglycemic clamp by 27 and 17%, respectively. Mean hepatic glucose production was -2.1 +/- 0.2 and -1.3 +/- 0.2 mg X kg-1 X min-1 as determined by the radioactive and stable isotope methodologies, respectively. Methodological error was an unlikely cause of this underestimation because it occurred with two different methodologies. The most likely explanation for underestimated rates of glucose disposal determined by the two types of isotope methodologies is discrepant metabolism of glucose tracers in comparison with unlabeled glucose

  1. Systematic review: Health care transition practice service models.

    Science.gov (United States)

    Betz, Cecily L; O'Kane, Lisa S; Nehring, Wendy M; Lobo, Marie L

    2016-01-01

    Nearly 750,000 adolescents and emerging adults with special health care needs (AEA-SHCN) enter into adulthood annually. The linkages to ensure the seamless transfer of care from pediatric to adult care and transition to adulthood for AEA-SHCN have yet to be realized. The purpose of this systematic review was to investigate the state of the science of health care transition (HCT) service models as described in quantitative investigations. A four-tier screening approach was used to obtain reviewed articles published from 2004 to 2013. A total of 17 articles were included in this review. Transfer of care was the most prominent intervention feature. Overall, using the Effective Public Health Practice Project criteria, the studies were rated as weak. Limitations included lack of control groups, rigorous designs and methodology, and incomplete intervention descriptions. As the findings indicate, HCT is an emerging field of practice that is largely in the exploratory stage of model development. Copyright © 2016 Elsevier Inc. All rights reserved.

  2. Modeling Systematicity and Individuality in Nonlinear Second Language Development: The Case of English Grammatical Morphemes

    Science.gov (United States)

    Murakami, Akira

    2016-01-01

    This article introduces two sophisticated statistical modeling techniques that allow researchers to analyze systematicity, individual variation, and nonlinearity in second language (L2) development. Generalized linear mixed-effects models can be used to quantify individual variation and examine systematic effects simultaneously, and generalized…

  3. A systematic approach for model verification: application on seven published activated sludge models.

    Science.gov (United States)

    Hauduc, H; Rieger, L; Takács, I; Héduit, A; Vanrolleghem, P A; Gillot, S

    2010-01-01

    The quality of simulation results can be significantly affected by errors in the published model (typing, inconsistencies, gaps or conceptual errors) and/or in the underlying numerical model description. Seven of the most commonly used activated sludge models have been investigated to point out the typing errors, inconsistencies and gaps in the model publications: ASM1; ASM2d; ASM3; ASM3 + Bio-P; ASM2d + TUD; New General; UCTPHO+. A systematic approach to verify models by tracking typing errors and inconsistencies in model development and software implementation is proposed. Then, stoichiometry and kinetic rate expressions are checked for each model and the errors found are reported in detail. An attached spreadsheet (see http://www.iwaponline.com/wst/06104/0898.pdf) provides corrected matrices with the calculations of all stoichiometric coefficients for the discussed biokinetic models and gives an example of proper continuity checks.

  4. Systematic development of reduced reaction mechanisms for dynamic modeling

    Science.gov (United States)

    Frenklach, M.; Kailasanath, K.; Oran, E. S.

    1986-01-01

    A method for systematically developing a reduced chemical reaction mechanism for dynamic modeling of chemically reactive flows is presented. The method is based on the postulate that if a reduced reaction mechanism faithfully describes the time evolution of both thermal and chain reaction processes characteristic of a more complete mechanism, then the reduced mechanism will describe the chemical processes in a chemically reacting flow with approximately the same degree of accuracy. Here this postulate is tested by producing a series of mechanisms of reduced accuracy, which are derived from a full detailed mechanism for methane-oxygen combustion. These mechanisms were then tested in a series of reactive flow calculations in which a large-amplitude sinusoidal perturbation is applied to a system that is initially quiescent and whose temperature is high enough to start ignition processes. Comparison of the results for systems with and without convective flow show that this approach produces reduced mechanisms that are useful for calculations of explosions and detonations. Extensions and applicability to flames are discussed.

  5. Systematic flood modelling to support flood-proof urban design

    Science.gov (United States)

    Bruwier, Martin; Mustafa, Ahmed; Aliaga, Daniel; Archambeau, Pierre; Erpicum, Sébastien; Nishida, Gen; Zhang, Xiaowei; Pirotton, Michel; Teller, Jacques; Dewals, Benjamin

    2017-04-01

    Urban flood risk is influenced by many factors such as hydro-meteorological drivers, existing drainage systems as well as vulnerability of population and assets. The urban fabric itself has also a complex influence on inundation flows. In this research, we performed a systematic analysis on how various characteristics of urban patterns control inundation flow within the urban area and upstream of it. An urban generator tool was used to generate over 2,250 synthetic urban networks of 1 km2. This tool is based on the procedural modelling presented by Parish and Müller (2001) which was adapted to generate a broader variety of urban networks. Nine input parameters were used to control the urban geometry. Three of them define the average length, orientation and curvature of the streets. Two orthogonal major roads, for which the width constitutes the fourth input parameter, work as constraints to generate the urban network. The width of secondary streets is given by the fifth input parameter. Each parcel generated by the street network based on a parcel mean area parameter can be either a park or a building parcel depending on the park ratio parameter. Three setback parameters constraint the exact location of the building whithin a building parcel. For each of synthetic urban network, detailed two-dimensional inundation maps were computed with a hydraulic model. The computational efficiency was enhanced by means of a porosity model. This enables the use of a coarser computational grid , while preserving information on the detailed geometry of the urban network (Sanders et al. 2008). These porosity parameters reflect not only the void fraction, which influences the storage capacity of the urban area, but also the influence of buildings on flow conveyance (dynamic effects). A sensitivity analysis was performed based on the inundation maps to highlight the respective impact of each input parameter characteristizing the urban networks. The findings of the study pinpoint

  6. Black carbon in the Arctic: the underestimated role of gas flaring and residential combustion emissions

    Directory of Open Access Journals (Sweden)

    A. Stohl

    2013-09-01

    annual mean Arctic BC surface concentrations due to residential combustion by 68% when using daily emissions. A large part (93% of this systematic increase can be captured also when using monthly emissions; the increase is compensated by a decreased BC burden at lower latitudes. In a comparison with BC measurements at six Arctic stations, we find that using daily-varying residential combustion emissions and introducing gas flaring emissions leads to large improvements of the simulated Arctic BC, both in terms of mean concentration levels and simulated seasonality. Case studies based on BC and carbon monoxide (CO measurements from the Zeppelin observatory appear to confirm flaring as an important BC source that can produce pollution plumes in the Arctic with a high BC / CO enhancement ratio, as expected for this source type. BC measurements taken during a research ship cruise in the White, Barents and Kara seas north of the region with strong flaring emissions reveal very high concentrations of the order of 200–400 ng m−3. The model underestimates these concentrations substantially, which indicates that the flaring emissions (and probably also other emissions in northern Siberia are rather under- than overestimated in our emission data set. Our results suggest that it may not be "vertical transport that is too strong or scavenging rates that are too low" and "opposite biases in these processes" in the Arctic and elsewhere in current aerosol models, as suggested in a recent review article (Bond et al., Bounding the role of black carbon in the climate system: a scientific assessment, J. Geophys. Res., 2013, but missing emission sources and lacking time resolution of the emission data that are causing opposite model biases in simulated BC concentrations in the Arctic and in the mid-latitudes.

  7. [Rational structures in health education models: basics and systematization].

    Science.gov (United States)

    Sánchez Moreno, A; Ramos García, E; Sánchez Estévez, V; Marset Campos, P

    1995-01-01

    The different Health Education (HE) models appeared in the scientific literature are analyzed, trying to eliminate the confusion produced by its great diversity, applying a general and systematic point of view. Due to the relevance of that topic in the activities of Health Promotion in Primary Health Care it is urgent a deep reappraisal due the heterogeneity of scientific papers dealing with that topic. The curriculum, as the confluence of thought and action in Health Education, is the basic concept thanks to which it is possible to integrate both scientific logic, the biological one and that pertaining to the social sciences. Of particular importance have been the different paradigms that have emerged in the field of HE from the beginning of the present century: a first generation with a "normative" point of view, a second one orientated from positivistic bases, and a third generation adopting an hermeneutic and critic nature. This third generation of paradigms in HE has taken distances from the behaviouristic and cognitive perspectives being more critical and participative. The principal scientific contributors in the field of HE, internationals as well as spaniards are studied and classified. The main conclusions obtained from this Health Education paradigm controversy are referred to both aspects: 1) planning, programming and evaluating activities, and 2) models, qualitative and quantitative methodologies. Emphasis is given to the need of including Community Participation in all phases of the process in critic methodologies of HE. It is postulated the critic paradigm as the only one able to integrate the rest of the scientific approaches in Health Education.

  8. the Underestimation of Isorene in Houston during the Texas 2013 DISCOVER-AQ Campaign

    Science.gov (United States)

    Choi, Y.; Diao, L.; Czader, B.; Li, X.; Estes, M. J.

    2014-12-01

    This study applies principal component analysis to aircraft data from the Texas 2013 DISCOVER-AQ (Deriving Information on Surface Conditions from Column and Vertically Resolved Observations Relevant to Air Quality) field campaign to characterize isoprene sources over Houston during September 2013. The biogenic isoprene signature appears in the third principal component and anthropogenic signals in the following two. Evaluations of the Community Multiscale Air Quality (CMAQ) model simulations of isoprene with airborne measurements are more accurate for suburban areas than for industrial areas. This study also compares model outputs to eight surface automated gas chromatograph (Auto-GC) measurements near the Houston ship channel industrial area during the nighttime and shows that modeled anthropogenic isoprene is underestimated by a factor of 10.60. This study employs a new simulation with a modified anthropogenic emissions inventory (constraining using the ratios of observed values versus simulated ones) that yields closer isoprene predictions at night with a reduction in the mean bias by 56.93%, implying that model-estimated isoprene emissions from the 2008 National Emission Inventory are underestimated in the city of Houston and that other climate models or chemistry and transport models using the same emissions inventory might also be underestimated in other Houston-like areas in the United States.

  9. BMI may underestimate the socioeconomic gradient in true obesity

    NARCIS (Netherlands)

    van den Berg, G.; van Eijsden, M.; Vrijkotte, T. G. M.; Gemke, R. J. B. J.

    2013-01-01

    Body mass index (BMI) does not make a distinction between fat mass and lean mass. In children, high fat mass appears to be associated with low maternal education, as well as low lean mass because maternal education is associated with physical activity. Therefore, BMI might underestimate true obesity

  10. Factors associated with parental underestimation of child's weight status.

    Science.gov (United States)

    Warkentin, Sarah; Mais, Laís A; Latorre, Maria do Rosário D O; Carnell, Susan; Taddei, José Augusto A C

    2017-08-18

    The aim of this study was to examine the prevalence of parental misperception of child weight status, and identify socioeconomic, anthropometric, behavioral and dietary factors associated with underestimation. Cross-sectional study. Data was collected in 14 Brazilian private schools. Parents of children aged 2-8 years (n=976) completed a self-reported questionnaire assessing their perception of their child's weight status, and sociodemographic, anthropometric, behavioral and dietary information. To measure the agreement between parental perception about child weight status and actual child weight status, the Kappa coefficient was estimated, and to investigate associations between parental underestimation and independent variables, chi-squared tests were performed, followed by multiple logistic regression, considering p≤0.05 for statistical significance. Overall, 48.05% of the parents incorrectly classified their child's weight. Specifically, 45.08% underestimated their child's weight status, with just 3% of parents overestimating. Children with higher body mass index (OR=2.03; p<0.001) and boys (OR=1.70; p<0.001) were more likely to have their weight status underestimated by parents. Since awareness of weight problems is essential for prevention and treatment, clinical practitioners should help parents at high risk of misperception to correctly evaluate their child's weight status. Copyright © 2017 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.

  11. Heritability: An Underestimated Effect in the Actiotope Model

    Science.gov (United States)

    Duan, Xiaoju

    2012-01-01

    A promising future has been drawn by Ziegler and Phillipson through illustrating how gifted education works as a system to be beneficial to everyone. Gifted education is individually designed and fostered. The whole system requires continuous adaptation and adjustment of both the individual and environment including schools, teachers, parents, and…

  12. What Pacific tsunamis tell us about underestimating hazard and risk

    Science.gov (United States)

    Goff, J. R.

    2011-12-01

    occurred in prehistory than have occurred in historic time. Larger events have occurred in prehistory than have been modelled in any probabilistic tsunami hazard assessment. This talk presents work that draws together much of the geological, TEK and archaeological evidence for such events and makes one key point - palaeotsunamis have had significant impact upon prehistoric coastal settlements and culture. We are currently underestimating the hazard and this does little to help in our assessment of the risk.

  13. Robust Underestimation of Speed During Driving: A Field Study.

    Science.gov (United States)

    Schütz, Alexander C; Billino, Jutta; Bodrogi, Peter; Polin, Dmitrij; Khanh, Tran Q; Gegenfurtner, Karl R

    2015-12-01

    Traffic reports consistently identify speeding as a substantial source of accidents. Adequate driving speeds require reliable speed estimation; however, there is still a lack of understanding how speed perception is biased during driving. Therefore, we ran three experiments measuring speed estimation under controlled driving and lighting conditions. In the first experiment, participants had to produce target speeds as drivers or had to judge driven speed as passengers. Measurements were performed at daylight and at night. In the second experiment, participants were required to produce target speeds at dusk, under rapidly changing lighting conditions. In the third experiment, we let two cars approach and pass each other. Drivers were instructed to produce target speeds as well as to judge the speed of the oncoming vehicle. Here measurements were performed at daylight and at night, with full or dipped headlights. We found that passengers underestimated driven speed by about 20% and drivers went over the instructed speed by roughly the same amount. Interestingly, the underestimation of speed extended to oncoming cars. All of these effects were independent of lighting conditions. The consistent underestimation of speed could lead to potentially fatal situations where drivers go faster than intended and judge oncoming traffic to approach slower than it actually is. © The Author(s) 2015.

  14. Critical appraisal and data extraction for systematic reviews of prediction modelling studies: the CHARMS checklist.

    Directory of Open Access Journals (Sweden)

    Karel G M Moons

    2014-10-01

    Full Text Available Carl Moons and colleagues provide a checklist and background explanation for critically appraising and extracting data from systematic reviews of prognostic and diagnostic prediction modelling studies. Please see later in the article for the Editors' Summary.

  15. Systematic approach for the identification of process reference models

    CSIR Research Space (South Africa)

    Van Der Merwe, A

    2009-02-01

    Full Text Available Process models are used in different application domains to capture knowledge on the process flow. Process reference models (PRM) are used to capture reusable process models, which should simplify the identification process of process models...

  16. Empathy gaps for social pain: why people underestimate the pain of social suffering.

    Science.gov (United States)

    Nordgren, Loran F; Banas, Kasia; MacDonald, Geoff

    2011-01-01

    In 5 studies, the authors examined the hypothesis that people have systematically distorted beliefs about the pain of social suffering. By integrating research on empathy gaps for physical pain (Loewenstein, 1996) with social pain theory (MacDonald & Leary, 2005), the authors generated the hypothesis that people generally underestimate the severity of social pain (ostracism, shame, etc.)--a biased judgment that is only corrected when people actively experience social pain for themselves. Using a social exclusion manipulation, Studies 1-4 found that nonexcluded participants consistently underestimated the severity of social pain compared with excluded participants, who had a heightened appreciation for social pain. This empathy gap for social pain occurred when participants evaluated both the pain of others (interpersonal empathy gap) as well as the pain participants themselves experienced in the past (intrapersonal empathy gap). The authors argue that beliefs about social pain are important because they govern how people react to socially distressing events. In Study 5, middle school teachers were asked to evaluate policies regarding emotional bullying at school. This revealed that actively experiencing social pain heightened the estimated pain of emotional bullying, which in turn led teachers to recommend both more comprehensive treatment for bullied students and greater punishment for students who bully. (PsycINFO Database Record (c) 2010 APA, all rights reserved).

  17. Individuals underestimate moderate and vigorous intensity physical activity.

    Directory of Open Access Journals (Sweden)

    Karissa L Canning

    Full Text Available BACKGROUND: It is unclear whether the common physical activity (PA intensity descriptors used in PA guidelines worldwide align with the associated percent heart rate maximum method used for prescribing relative PA intensities consistently between sexes, ethnicities, age categories and across body mass index (BMI classifications. OBJECTIVES: The objectives of this study were to determine whether individuals properly select light, moderate and vigorous intensity PA using the intensity descriptions in PA guidelines and determine if there are differences in estimation across sex, ethnicity, age and BMI classifications. METHODS: 129 adults were instructed to walk/jog at a "light," "moderate" and "vigorous effort" in a randomized order. The PA intensities were categorized as being below, at or above the following %HRmax ranges of: 50-63% for light, 64-76% for moderate and 77-93% for vigorous effort. RESULTS: On average, people correctly estimated light effort as 51.5±8.3%HRmax but underestimated moderate effort as 58.7±10.7%HRmax and vigorous effort as 69.9±11.9%HRmax. Participants walked at a light intensity (57.4±10.5%HRmax when asked to walk at a pace that provided health benefits, wherein 52% of participants walked at a light effort pace, 19% walked at a moderate effort and 5% walked at a vigorous effort pace. These results did not differ by sex, ethnicity or BMI class. However, younger adults underestimated moderate and vigorous intensity more so than middle-aged adults (P<0.05. CONCLUSION: When the common PA guideline descriptors were aligned with the associated %HRmax ranges, the majority of participants underestimated the intensity of PA that is needed to obtain health benefits. Thus, new subjective descriptions for moderate and vigorous intensity may be warranted to aid individuals in correctly interpreting PA intensities.

  18. Guiding exploration in conformational feature space with Lipschitz underestimation for ab-initio protein structure prediction.

    Science.gov (United States)

    Hao, Xiaohu; Zhang, Guijun; Zhou, Xiaogen

    2018-04-01

    Computing conformations which are essential to associate structural and functional information with gene sequences, is challenging due to the high dimensionality and rugged energy surface of the protein conformational space. Consequently, the dimension of the protein conformational space should be reduced to a proper level, and an effective exploring algorithm should be proposed. In this paper, a plug-in method for guiding exploration in conformational feature space with Lipschitz underestimation (LUE) for ab-initio protein structure prediction is proposed. The conformational space is converted into ultrafast shape recognition (USR) feature space firstly. Based on the USR feature space, the conformational space can be further converted into Underestimation space according to Lipschitz estimation theory for guiding exploration. As a consequence of the use of underestimation model, the tight lower bound estimate information can be used for exploration guidance, the invalid sampling areas can be eliminated in advance, and the number of energy function evaluations can be reduced. The proposed method provides a novel technique to solve the exploring problem of protein conformational space. LUE is applied to differential evolution (DE) algorithm, and metropolis Monte Carlo(MMC) algorithm which is available in the Rosetta; When LUE is applied to DE and MMC, it will be screened by the underestimation method prior to energy calculation and selection. Further, LUE is compared with DE and MMC by testing on 15 small-to-medium structurally diverse proteins. Test results show that near-native protein structures with higher accuracy can be obtained more rapidly and efficiently with the use of LUE. Copyright © 2018 Elsevier Ltd. All rights reserved.

  19. Underestimating nearby nature: affective forecasting errors obscure the happy path to sustainability.

    Science.gov (United States)

    Nisbet, Elizabeth K; Zelenski, John M

    2011-09-01

    Modern lifestyles disconnect people from nature, and this may have adverse consequences for the well-being of both humans and the environment. In two experiments, we found that although outdoor walks in nearby nature made participants much happier than indoor walks did, participants made affective forecasting errors, such that they systematically underestimated nature's hedonic benefit. The pleasant moods experienced on outdoor nature walks facilitated a subjective sense of connection with nature, a construct strongly linked with concern for the environment and environmentally sustainable behavior. To the extent that affective forecasts determine choices, our findings suggest that people fail to maximize their time in nearby nature and thus miss opportunities to increase their happiness and relatedness to nature. Our findings suggest a happy path to sustainability, whereby contact with nature fosters individual happiness and environmentally responsible behavior.

  20. Consequences of Underestimating Impalement Bicycle Handlebar Injuries in Children.

    Science.gov (United States)

    Ramos-Irizarry, Carmen T; Swain, Shakeva; Troncoso-Munoz, Samantha; Duncan, Malvina

    Impalement bicycle handlebar trauma injuries are rare; however, on initial assessment, they have the potential of being underestimated. We reviewed our prospective trauma database of 3,894 patients for all bicycle injuries from January 2010 to May 2015. Isolated pedal bike injuries were reported in 2.6% (N = 101) of the patients who were admitted to the trauma service. Fifteen patients suffered direct handlebar trauma. Patients were grouped into blunt trauma (n = 12) and impalement trauma (n = 3). We examined gender, age, injury severity score (ISS), Glasgow Coma Scale score, use of protective devices, need for surgical intervention, need for intensive care (ICU), and hospital length of stay. Mean age was 9.6 years. All children with penetrating injuries were males. Mean ISS was less than 9 in both groups. None of the children were wearing bicycle helmets. Three patients who sustained blunt injuries required ICU care due to associated injuries. All of the children with impalement injuries required several surgical interventions. These injuries included a traumatic direct inguinal hernia, a medial groin and thigh laceration with resultant femoral hernia, and a lateral deep thigh laceration. Impalement bicycle handlebar injuries must be thoroughly evaluated, with a similar importance given to blunt injuries. A high index of suspicion must be maintained when examining children with handlebar impalement injuries, as they are at risk for missed or underestimation of their injuries.

  1. Systematic and reliable multiscale modelling of lithium batteries

    Science.gov (United States)

    Atalay, Selcuk; Schmuck, Markus

    2017-11-01

    Motivated by the increasing interest in lithium batteries as energy storage devices (e.g. cars/bycicles/public transport, social robot companions, mobile phones, and tablets), we investigate three basic cells: (i) a single intercalation host; (ii) a periodic arrangement of intercalation hosts; and (iii) a rigorously upscaled formulation of (ii) as initiated in. By systematically accounting for Li transport and interfacial reactions in (i)-(iii), we compute the associated chracteristic current-voltage curves and power densities. Finally, we discuss the influence of how the intercalation particles are arranged. Our findings are expected to improve the understanding of how microscopic properties affect the battery behaviour observed on the macroscale and at the same time, the upscaled formulation (iii) serves as an efficient computational tool. This work has been supported by EPSRC, UK, through the Grant No. EP/P011713/1.

  2. Simulation Models for Socioeconomic Inequalities in Health: A Systematic Review

    Directory of Open Access Journals (Sweden)

    Niko Speybroeck

    2013-11-01

    Full Text Available Background: The emergence and evolution of socioeconomic inequalities in health involves multiple factors interacting with each other at different levels. Simulation models are suitable for studying such complex and dynamic systems and have the ability to test the impact of policy interventions in silico. Objective: To explore how simulation models were used in the field of socioeconomic inequalities in health. Methods: An electronic search of studies assessing socioeconomic inequalities in health using a simulation model was conducted. Characteristics of the simulation models were extracted and distinct simulation approaches were identified. As an illustration, a simple agent-based model of the emergence of socioeconomic differences in alcohol abuse was developed. Results: We found 61 studies published between 1989 and 2013. Ten different simulation approaches were identified. The agent-based model illustration showed that multilevel, reciprocal and indirect effects of social determinants on health can be modeled flexibly. Discussion and Conclusions: Based on the review, we discuss the utility of using simulation models for studying health inequalities, and refer to good modeling practices for developing such models. The review and the simulation model example suggest that the use of simulation models may enhance the understanding and debate about existing and new socioeconomic inequalities of health frameworks.

  3. The Chain Information Model: a systematic approach for food product development

    NARCIS (Netherlands)

    Benner, M.

    2005-01-01

    The chain information model has been developed to increase the success rate of new food products. The uniqueness of this approach is that it approaches the problem from a chain perspective and starts with the consumer. The model can be used to analyse the production chain in a systematic way. This

  4. In vitro biofilm models to study dental caries: a systematic review

    NARCIS (Netherlands)

    Maske, T.T.; Sande, F.H. van de; Arthur, R.A.; Huysmans, M.C.; Cenci, M.S.

    2017-01-01

    The aim of this systematic review is to characterize and discuss key methodological aspects of in vitro biofilm models for caries-related research and to verify the reproducibility and dose-response of models considering the response to anti-caries and/or antimicrobial substances. Inclusion criteria

  5. Multivariate models of subjective caregiver burden in dementia: A systematic review

    NARCIS (Netherlands)

    van der Lee, J.H.; Bakker, T.J.E.M.; Duivenvoorden, H.J.; Dröes, R.M.

    2014-01-01

    Background: Burden in dementia caregivers is a complex and multidimensional construct. Several models of burden and other representations of burden like depression or mental health are described in literature. To clarify the state of science, we systematically reviewed complex models that include

  6. A digital tool set for systematic model design in process-engineering education

    NARCIS (Netherlands)

    Schaaf, van der H.; Tramper, J.; Hartog, R.J.M.; Vermuë, M.H.

    2006-01-01

    One of the objectives of the process technology curriculum at Wageningen University is that students learn how to design mathematical models in the context of process engineering, using a systematic problem analysis approach. Students find it difficult to learn to design a model and little material

  7. Underestimating our influence over others' unethical behavior and decisions.

    Science.gov (United States)

    Bohns, Vanessa K; Roghanizad, M Mahdi; Xu, Amy Z

    2014-03-01

    We examined the psychology of "instigators," people who surround an unethical act and influence the wrongdoer (the "actor") without directly committing the act themselves. In four studies, we found that instigators of unethical acts underestimated their influence over actors. In Studies 1 and 2, university students enlisted other students to commit a "white lie" (Study 1) or commit a small act of vandalism (Study 2) after making predictions about how easy it would be to get their fellow students to do so. In Studies 3 and 4, online samples of participants responded to hypothetical vignettes, for example, about buying children alcohol and taking office supplies home for personal use. In all four studies, instigators failed to recognize the social pressure they levied on actors through simple unethical suggestions, that is, the discomfort actors would experience by making a decision that was inconsistent with the instigator's suggestion.

  8. Zinc deficiency: a frequent and underestimated complication after bariatric surgery.

    Science.gov (United States)

    Sallé, Agnès; Demarsy, Delphine; Poirier, Anne Lise; Lelièvre, Bénédicte; Topart, Philippe; Guilloteau, Gérard; Bécouarn, Guillaume; Rohmer, Vincent

    2010-12-01

    Although zinc deficiency is common after bariatric surgery, its incidence is underestimated. The objective was to monitor zinc and nutritional status before and 6, 12 and 24 months (M6, M12 and M24) after gastric bypass (Roux-en-Y gastric bypass), sleeve gastrectomy and biliopancreatic diversion with duodenal switch (DS) in patients receiving systematised nutritional care. Data for 324 morbidly obese patients (mean body mass index 46.2 ± 7.3 kg/m(2)) were reviewed retrospectively. The follow-up period was 6 months for 272 patients, 12 months for 175, and 24 months for 70. Anthropometric, dietary and serum albumin, prealbumin, zinc, iron and transferrin saturation measures were determined at each timepoint. Nine percent of patients had zinc deficiency pre-operatively. Zinc deficiency was present in 42.5% of the population at M12 and then remained stable. Zinc deficiency was significantly more frequent after DS, with a prevalence of 91.7% at M12. Between M0 and M6, variation in plasma prealbumin, surgery type and zinc supplementation explained 27.2% of the variance in plasma zinc concentration. Surgery type explained 22.1% of this variance between M0 and M24. Mean supplemental zinc intake was low (22 mg/day). The percentage of patients taking zinc supplementation at M6, M12 and M24 was 8.9%, 20.6% and 29%, respectively. Reduced protein intake, impaired zinc absorption and worsening compensatory mechanisms contribute to zinc deficiency. The mechanisms involved differ according to the type of surgery and time since surgery. Zinc supplementation is necessary early after bariatric surgery, but this requirement is often underestimated or is inadequate.

  9. A Systematic Literature Review of Agile Maturity Model Research

    OpenAIRE

    Vaughan Henriques; Maureen Tanner

    2017-01-01

    Background/Aim/Purpose: A commonly implemented software process improvement framework is the capability maturity model integrated (CMMI). Existing literature indicates higher levels of CMMI maturity could result in a loss of agility due to its organizational focus. To maintain agility, research has focussed attention on agile maturity models. The objective of this paper is to find the common research themes and conclusions in agile maturity model research. Methodology: This research adop...

  10. Systematic modeling for free stators of rotary - Piezoelectric ultrasonic motors

    DEFF Research Database (Denmark)

    Mojallali, Hamed; Amini, Rouzbeh; Izadi-Zamanabadi, Roozbeh

    2007-01-01

    An equivalent circuit model with complex elements is presented in this paper to describe the free stator model of traveling wave piezoelectric motors. The mechanical, dielectric and piezoelectric losses associated with the vibrator are considered by introducing the imaginary part to the equivalent...... the measurements of a recently developed piezoelectric motor and a well known USR60....

  11. Model uncertainty and systematic risk in US banking

    NARCIS (Netherlands)

    Baele, L.T.M.; De Bruyckere, Valerie; De Jonghe, O.G.; Vander Vennet, Rudi

    This paper uses Bayesian Model Averaging to examine the driving factors of equity returns of US Bank Holding Companies. BMA has as an advantage over OLS that it accounts for the considerable uncertainty about the correct set (model) of bank risk factors. We find that out of a broad set of 12 risk

  12. Bayesian Network Models in Cyber Security: A Systematic Review

    NARCIS (Netherlands)

    Chockalingam, S.; Pieters, W.; Herdeiro Teixeira, A.M.; van Gelder, P.H.A.J.M.; Lipmaa, Helger; Mitrokotsa, Aikaterini; Matulevicius, Raimundas

    2017-01-01

    Bayesian Networks (BNs) are an increasingly popular modelling technique in cyber security especially due to their capability to overcome data limitations. This is also instantiated by the growth of BN models development in cyber security. However, a comprehensive comparison and analysis of these

  13. Using logic model methods in systematic review synthesis: describing complex pathways in referral management interventions.

    Science.gov (United States)

    Baxter, Susan K; Blank, Lindsay; Woods, Helen Buckley; Payne, Nick; Rimmer, Melanie; Goyder, Elizabeth

    2014-05-10

    There is increasing interest in innovative methods to carry out systematic reviews of complex interventions. Theory-based approaches, such as logic models, have been suggested as a means of providing additional insights beyond that obtained via conventional review methods. This paper reports the use of an innovative method which combines systematic review processes with logic model techniques to synthesise a broad range of literature. The potential value of the model produced was explored with stakeholders. The review identified 295 papers that met the inclusion criteria. The papers consisted of 141 intervention studies and 154 non-intervention quantitative and qualitative articles. A logic model was systematically built from these studies. The model outlines interventions, short term outcomes, moderating and mediating factors and long term demand management outcomes and impacts. Interventions were grouped into typologies of practitioner education, process change, system change, and patient intervention. Short-term outcomes identified that may result from these interventions were changed physician or patient knowledge, beliefs or attitudes and also interventions related to changed doctor-patient interaction. A range of factors which may influence whether these outcomes lead to long term change were detailed. Demand management outcomes and intended impacts included content of referral, rate of referral, and doctor or patient satisfaction. The logic model details evidence and assumptions underpinning the complex pathway from interventions to demand management impact. The method offers a useful addition to systematic review methodologies. PROSPERO registration number: CRD42013004037.

  14. Physiologically Based Pharmacokinetic (PBPK) Modeling and Simulation Approaches: A Systematic Review of Published Models, Applications, and Model Verification

    Science.gov (United States)

    Sager, Jennifer E.; Yu, Jingjing; Ragueneau-Majlessi, Isabelle

    2015-01-01

    Modeling and simulation of drug disposition has emerged as an important tool in drug development, clinical study design and regulatory review, and the number of physiologically based pharmacokinetic (PBPK) modeling related publications and regulatory submissions have risen dramatically in recent years. However, the extent of use of PBPK modeling by researchers, and the public availability of models has not been systematically evaluated. This review evaluates PBPK-related publications to 1) identify the common applications of PBPK modeling; 2) determine ways in which models are developed; 3) establish how model quality is assessed; and 4) provide a list of publically available PBPK models for sensitive P450 and transporter substrates as well as selective inhibitors and inducers. PubMed searches were conducted using the terms “PBPK” and “physiologically based pharmacokinetic model” to collect published models. Only papers on PBPK modeling of pharmaceutical agents in humans published in English between 2008 and May 2015 were reviewed. A total of 366 PBPK-related articles met the search criteria, with the number of articles published per year rising steadily. Published models were most commonly used for drug-drug interaction predictions (28%), followed by interindividual variability and general clinical pharmacokinetic predictions (23%), formulation or absorption modeling (12%), and predicting age-related changes in pharmacokinetics and disposition (10%). In total, 106 models of sensitive substrates, inhibitors, and inducers were identified. An in-depth analysis of the model development and verification revealed a lack of consistency in model development and quality assessment practices, demonstrating a need for development of best-practice guidelines. PMID:26296709

  15. Models of care in nursing: a systematic review.

    Science.gov (United States)

    Fernandez, Ritin; Johnson, Maree; Tran, Duong Thuy; Miranda, Charmaine

    2012-12-01

    This review investigated the effect of the various models of nursing care delivery using the diverse levels of nurses on patient and nursing outcomes. All published studies that investigated patient and nursing outcomes were considered. Studies were included if the nursing delivery models only included nurses with varying skill levels. A literature search was performed using the following databases: Medline (1985-2011), CINAHL (1985-2011), EMBASE (1985 to current) and the Cochrane Controlled Studies Register (Issue 3, 2011 of Cochrane Library). In addition, the reference lists of relevant studies and conference proceedings were also scrutinised. Two reviewers independently assessed the eligibility of the studies for inclusion in the review, the methodological quality and extracted details of eligible studies. Data were analysed using the RevMan software (Nordic Cochrane Centre, Copenhagen, Denmark). Fourteen studies were included in this review. The results reveal that implementation of the team nursing model of care resulted in significantly decreased incidence of medication errors and adverse intravenous outcomes, as well as lower pain scores among patients; however, there was no effect of this model of care on the incidence of falls. Wards that used a hybrid model demonstrated significant improvement in quality of patient care, but no difference in incidence of pressure areas or infection rates. There were no significant differences in nursing outcomes relating to role clarity, job satisfaction and nurse absenteeism rates between any of the models of care. Based on the available evidence, a predominance of team nursing within the comparisons is suggestive of its popularity. Patient outcomes, nurse satisfaction, absenteeism and role clarity/confusion did not differ across model comparisons. Little benefit was found within primary nursing comparisons and the cost effectiveness of team nursing over other models remains debatable. Nonetheless, team nursing does

  16. Quality of life and time to death: have the health gains of preventive interventions been underestimated?

    Science.gov (United States)

    Gheorghe, Maria; Brouwer, Werner B F; van Baal, Pieter H M

    2015-04-01

    This article explores the implications of the relation between quality of life (QoL) and time to death (TTD) for economic evaluations of preventive interventions. By using health survey data on QoL for the general Dutch population linked to the mortality registry, we quantify the magnitude of this relationship. For addressing specific features of the nonstandard QoL distribution such as boundness, skewness, and heteroscedasticity, we modeled QoL using a generalized additive model for location, scale, and shape (GAMLSS) with a β inflated outcome distribution. Our empirical results indicate that QoL decreases when approaching death, suggesting that there is a strong relationship between TTD and QoL. Predictions of different regression models revealed that ignoring this relationship results in an underestimation of the quality-adjusted life year (QALY) gains for preventive interventions. The underestimation ranged between 3% and 7% and depended on age, the number of years gained from the intervention, and the discount rate used. © The Author(s) 2014.

  17. A Systematic Modelling Framework for Phase Transfer Catalyst Systems

    DEFF Research Database (Denmark)

    Anantpinijwatna, Amata; Sales-Cruz, Mauricio; Hyung Kim, Sun

    2016-01-01

    equilibria, as well as kinetic mechanisms and rates. This paper presents a modelling framework for design and analysis of PTC systems that requires a minimum amount of experimental data to develop and employ the necessary thermodynamic and reaction models and embeds them into a reactor model for simulation...... in an aqueous phase. These reacting systems are receiving increased attention as novel organic synthesis options due to their flexible operation, higher product yields, and ability to avoid hazardous or expensive solvents. Major considerations in the design and analysis of PTC systems are physical and chemical....... The application of the framework is made to two cases in order to highlight the performance and issues of activity coefficient models for predicting design and operation and the effects when different organic solvents are employed....

  18. Insights on the impact of systematic model errors on data assimilation performance in changing catchments

    Science.gov (United States)

    Pathiraja, S.; Anghileri, D.; Burlando, P.; Sharma, A.; Marshall, L.; Moradkhani, H.

    2018-03-01

    The global prevalence of rapid and extensive land use change necessitates hydrologic modelling methodologies capable of handling non-stationarity. This is particularly true in the context of Hydrologic Forecasting using Data Assimilation. Data Assimilation has been shown to dramatically improve forecast skill in hydrologic and meteorological applications, although such improvements are conditional on using bias-free observations and model simulations. A hydrologic model calibrated to a particular set of land cover conditions has the potential to produce biased simulations when the catchment is disturbed. This paper sheds new light on the impacts of bias or systematic errors in hydrologic data assimilation, in the context of forecasting in catchments with changing land surface conditions and a model calibrated to pre-change conditions. We posit that in such cases, the impact of systematic model errors on assimilation or forecast quality is dependent on the inherent prediction uncertainty that persists even in pre-change conditions. Through experiments on a range of catchments, we develop a conceptual relationship between total prediction uncertainty and the impacts of land cover changes on the hydrologic regime to demonstrate how forecast quality is affected when using state estimation Data Assimilation with no modifications to account for land cover changes. This work shows that systematic model errors as a result of changing or changed catchment conditions do not always necessitate adjustments to the modelling or assimilation methodology, for instance through re-calibration of the hydrologic model, time varying model parameters or revised offline/online bias estimation.

  19. Body Size Estimation from Early to Middle Childhood: Stability of Underestimation, BMI, and Gender Effects

    Directory of Open Access Journals (Sweden)

    Silje Steinsbekk

    2017-11-01

    Full Text Available Individuals who are overweight are more likely to underestimate their body size than those who are normal weight, and overweight underestimators are less likely to engage in weight loss efforts. Underestimation of body size might represent a barrier to prevention and treatment of overweight; thus insight in how underestimation of body size develops and tracks through the childhood years is needed. The aim of the present study was therefore to examine stability in children’s underestimation of body size, exploring predictors of underestimation over time. The prospective path from underestimation to BMI was also tested. In a Norwegian cohort of 6 year olds, followed up at ages 8 and 10 (analysis sample: n = 793 body size estimation was captured by the Children’s Body Image Scale, height and weight were measured and BMI calculated. Overall, children were more likely to underestimate than overestimate their body size. Individual stability in underestimation was modest, but significant. Higher BMI predicted future underestimation, even when previous underestimation was adjusted for, but there was no evidence for the opposite direction of influence. Boys were more likely than girls to underestimate their body size at ages 8 and 10 (age 8: 38.0% vs. 24.1%; Age 10: 57.9% vs. 30.8% and showed a steeper increase in underestimation with age compared to girls. In conclusion, the majority of 6, 8, and 10-year olds correctly estimate their body size (prevalence ranging from 40 to 70% depending on age and gender, although a substantial portion perceived themselves to be thinner than they actually were. Higher BMI forecasted future underestimation, but underestimation did not increase the risk for excessive weight gain in middle childhood.

  20. Body Size Estimation from Early to Middle Childhood: Stability of Underestimation, BMI, and Gender Effects.

    Science.gov (United States)

    Steinsbekk, Silje; Klöckner, Christian A; Fildes, Alison; Kristoffersen, Pernille; Rognsås, Stine L; Wichstrøm, Lars

    2017-01-01

    Individuals who are overweight are more likely to underestimate their body size than those who are normal weight, and overweight underestimators are less likely to engage in weight loss efforts. Underestimation of body size might represent a barrier to prevention and treatment of overweight; thus insight in how underestimation of body size develops and tracks through the childhood years is needed. The aim of the present study was therefore to examine stability in children's underestimation of body size, exploring predictors of underestimation over time. The prospective path from underestimation to BMI was also tested. In a Norwegian cohort of 6 year olds, followed up at ages 8 and 10 (analysis sample: n = 793) body size estimation was captured by the Children's Body Image Scale, height and weight were measured and BMI calculated. Overall, children were more likely to underestimate than overestimate their body size. Individual stability in underestimation was modest, but significant. Higher BMI predicted future underestimation, even when previous underestimation was adjusted for, but there was no evidence for the opposite direction of influence. Boys were more likely than girls to underestimate their body size at ages 8 and 10 (age 8: 38.0% vs. 24.1%; Age 10: 57.9% vs. 30.8%) and showed a steeper increase in underestimation with age compared to girls. In conclusion, the majority of 6, 8, and 10-year olds correctly estimate their body size (prevalence ranging from 40 to 70% depending on age and gender), although a substantial portion perceived themselves to be thinner than they actually were. Higher BMI forecasted future underestimation, but underestimation did not increase the risk for excessive weight gain in middle childhood.

  1. Business process maturity models : A systematic literature review

    NARCIS (Netherlands)

    Tarhan, Ayca; Turetken, Oktay; Reijers, Hajo A.

    2016-01-01

    Context The number of maturity models proposed in the area of Business Process Management (BPM) has increased considerably in the last decade. However, there are a number of challenges, such as the limited empirical studies on their validation and a limited extent of actionable properties of these

  2. The Use of Decision-Analytic Models in Atopic Eczema: A Systematic Review and Critical Appraisal.

    Science.gov (United States)

    McManus, Emma; Sach, Tracey; Levell, Nick

    2018-01-01

    The objective of this systematic review was to identify and assess the quality of published economic decision-analytic models within atopic eczema against best practice guidelines, with the intention of informing future decision-analytic models within this condition. A systematic search of the following online databases was performed: MEDLINE, EMBASE, Cumulative Index to Nursing and Allied Health Literature (CINAHL), Cochrane Central Register of Controlled Trials, Database of Abstracts of Reviews of Effects, Cochrane Database of Systematic Reviews, NHS Economic Evaluation Database, EconLit, Scopus, Health Technology Assessment, Cost-Effectiveness Analysis Registry and Web of Science. Papers were eligible for inclusion if they described a decision-analytic model evaluating both the costs and benefits associated with an intervention or prevention for atopic eczema. Data were extracted using a standardised form by two independent reviewers, whilst quality was assessed using the model-specific Philips criteria. Twenty-four models were identified, evaluating either preventions (n = 12) or interventions (n = 12): 14 reported using a Markov modelling approach, four utilised decision trees and one a discrete event simulation, whilst five did not specify the approach. The majority, 22 studies, reported that the intervention was dominant or cost effective, given the assumptions and analytical perspective taken. Notably, the models tended to be short-term (16 used a time horizon of ≤1 year), often providing little justification for the limited time horizon chosen. The methodological and reporting quality of the studies was generally weak, with only seven studies fulfilling more than 50% of their applicable Philips criteria. This is the first systematic review of decision models in eczema. Whilst the majority of models reported favourable outcomes in terms of the cost effectiveness of the new intervention, the usefulness of these findings for decision-making is

  3. Underestimated interannual variability of East Asian summer rainfall under climate change

    Science.gov (United States)

    Ren, Yongjian; Song, Lianchun; Xiao, Ying; Du, Liangmin

    2018-02-01

    This study evaluates the performance of climate models in simulating the climatological mean and interannual variability of East Asian summer rainfall (EASR) using Coupled Model Intercomparison Project Phase 5 (CMIP5). Compared to the observation, the interannual variability of EASR during 1979-2005 is underestimated by the CMIP5 with a range of 0.86 16.08%. Based on bias correction of CMIP5 simulations with historical data, the reliability of future projections will be enhanced. The corrected EASR under representative concentration pathways (RCPs) 4.5 and 8.5 increases by 5.6 and 7.5% during 2081-2100 relative to the baseline of 1986-2005, respectively. After correction, the areas with both negative and positive anomalies decrease, which are mainly located in the South China Sea and central China, and southern China and west of the Philippines, separately. In comparison to the baseline, the interannual variability of EASR increases by 20.8% under RCP4.5 but 26.2% under RCP8.5 in 2006-2100, which is underestimated by 10.7 and 11.1% under both RCPs in the original CMIP5 simulation. Compared with the mean precipitation, the interannual variability of EASR is notably larger under global warming. Thus, the probabilities of floods and droughts may increase in the future.

  4. Systematic design of a sawtooth period feedback controller using a Kadomtsev-Porcelli sawtooth model

    NARCIS (Netherlands)

    Witvoet, G.; Baar, M.R. de; Westerhof, E.; Steinbuch, M.; Doelman, N.J.

    2011-01-01

    A systematic methodology for structured design of feedback controllers for the sawtooth period is presented, based on dedicated identification of the sawtooth dynamics. Therefore, a combined Kadomtsev-Porcelli model of a sawtoothing plasma actuated by an electron cyclotron current drive system has

  5. The Psychology Department Model Advisement Procedure: A Comprehensive, Systematic Approach to Career Development Advisement

    Science.gov (United States)

    Howell-Carter, Marya; Nieman-Gonder, Jennifer; Pellegrino, Jennifer; Catapano, Brittani; Hutzel, Kimberly

    2016-01-01

    The MAP (Model Advisement Procedure) is a comprehensive, systematic approach to developmental student advisement. The MAP was implemented to improve advisement consistency, improve student preparation for internships/senior projects, increase career exploration, reduce career uncertainty, and, ultimately, improve student satisfaction with the…

  6. Topic Modeling in Sentiment Analysis: A Systematic Review

    Directory of Open Access Journals (Sweden)

    Toqir Ahmad Rana

    2016-06-01

    Full Text Available With the expansion and acceptance of Word Wide Web, sentiment analysis has become progressively popular research area in information retrieval and web data analysis. Due to the huge amount of user-generated contents over blogs, forums, social media, etc., sentiment analysis has attracted researchers both in academia and industry, since it deals with the extraction of opinions and sentiments. In this paper, we have presented a review of topic modeling, especially LDA-based techniques, in sentiment analysis. We have presented a detailed analysis of diverse approaches and techniques, and compared the accuracy of different systems among them. The results of different approaches have been summarized, analyzed and presented in a sophisticated fashion. This is the really effort to explore different topic modeling techniques in the capacity of sentiment analysis and imparting a comprehensive comparison among them.

  7. The risk of sustained sexual transmission of Zika is underestimated.

    Directory of Open Access Journals (Sweden)

    Antoine Allard

    2017-09-01

    Full Text Available Pathogens often follow more than one transmission route during outbreaks-from needle sharing plus sexual transmission of HIV to small droplet aerosol plus fomite transmission of influenza. Thus, controlling an infectious disease outbreak often requires characterizing the risk associated with multiple mechanisms of transmission. For example, during the Ebola virus outbreak in West Africa, weighing the relative importance of funeral versus health care worker transmission was essential to stopping disease spread. As a result, strategic policy decisions regarding interventions must rely on accurately characterizing risks associated with multiple transmission routes. The ongoing Zika virus (ZIKV outbreak challenges our conventional methodologies for translating case-counts into route-specific transmission risk. Critically, most approaches will fail to accurately estimate the risk of sustained sexual transmission of a pathogen that is primarily vectored by a mosquito-such as the risk of sustained sexual transmission of ZIKV. By computationally investigating a novel mathematical approach for multi-route pathogens, our results suggest that previous epidemic threshold estimates could under-estimate the risk of sustained sexual transmission by at least an order of magnitude. This result, coupled with emerging clinical, epidemiological, and experimental evidence for an increased risk of sexual transmission, would strongly support recent calls to classify ZIKV as a sexually transmitted infection.

  8. Evidence that protein requirements have been significantly underestimated.

    Science.gov (United States)

    Elango, Rajavel; Humayun, Mohammad A; Ball, Ronald O; Pencharz, Paul B

    2010-01-01

    This review discusses recent evidence that suggests a significant underestimation of protein requirements in adult humans. Traditionally, total protein requirements for humans have been determined using nitrogen balance. The recent Dietary Reference Intake recommendations for mean and population-safe intakes of 0.66 and 0.8 g/kg/day, respectively, of high-quality protein in adult humans are based on a meta-analysis of nitrogen balance studies using single linear regression analysis. We reanalyzed existing nitrogen balance studies using two-phase linear regression analysis and obtained mean and safe protein requirements of 0.91 and 0.99 g/kg/day, respectively. The two-phase linear regression analysis is considered more appropriate for biological analysis of dose-response curves. Considering the inherent problems associated with the nitrogen balance method, we developed an alternative method, the indicator amino acid oxidation technique, to determine protein requirements The mean and population-safe requirements in adult men were determined to be 0.93 and 1.2 g/kg/day and are 41 and 50%, respectively, higher than the current Dietary Reference Intakes recommendations. The indicator amino acid oxidation-based requirement values of 0.93 and 1.2 g protein/kg/day and the reanalysis of existing nitrogen balance studies are significantly higher than current recommendations. Therefore, there is an urgent need to reassess recommendations for protein intake in adult humans.

  9. Does I-131-MIBG underestimate skeletal disease burden in neuroblastoma?

    Directory of Open Access Journals (Sweden)

    Barai Sukanta

    2004-10-01

    Full Text Available Background: Controversy persists as to the need for both MIBG and bone scanning in routine evaluation of neuroblastoma. Aim: To compare the efficacy of I-131- metaiodobenzylguanidine (MIBG scan against that of conventional Tc99m- methylene diphosphonate (MDP bone scan for the detection of skeletal deposition of neuroblastoma. Methods and Material: The study included 57 patients (36 boys, 21 girls: age range 1-14 years of neuroblastoma who underwent both bone scan with Tc99m-MDP and I-131-MIBG scan within 15 days of each other at presentation and during follow-up. Results: At presentation 11(19.2% patients had evidence of skeletal metastases on MDP scan against 7 patients who showed bony secondaries on MIBG scan. Of the 7 patients, with positive MIBG and MDP scans, MDP scan detected 11 sites whereas MIBG scan detected 7 sites. On follow-up study, 3 patients with initial abnormal MDP scan but normal MIBG scan, developed skeletal metastases detectable on MIBG scan, whereas 3 of the 46 patients who had normal MDP and MIBG scan at presentation; developed skeletal metastases detectable on MDP scan. MIBG scan was concordant in 2 of them but was normal in the third patient. Conclusion: I-131-MIBG underestimates skeletal disease burden in neuroblastoma. Therefore, Tc99m-MDP bone scan should remain a part of routine assessment of patients with neuroblastoma.

  10. Congenital cytomegalovirus infection in Central Germany: an underestimated risk.

    Science.gov (United States)

    Rütten, Hannah; Rissmann, Anke; Brett, Birgit; Costa, Serban-Dan; Doßow, Birgit; Färber, Jacqueline; Fest, Stefan; Fritzsch, Christiane; Lux, Anke; Päge, Ilona; Spillner, Claudia; Redlich, Anke

    2017-08-01

    This is the first study to determine the cytomegalovirus (CMV) seronegativity rate for women of childbearing age in Saxony-Anhalt and to determine the prevalence of clinically relevant congenital CMV (cCMV) infection in Central Germany, because there are no valid data available. The retrospective study was undertaken between January 2005 and December 2015. For the first time in Germany, the following seven data sources were used to analyze the prevalence of clinically relevant cCMV infection and the rate of CMV seronegative women of childbearing age: CMV Screening in maternity unit, University Women's Hospital, Social Paediatrics Centre (SPC), Malformation Monitoring Centre (MMC), Newborn Hearing Screening (NHS), Neonatal Intensive Care Unit (NICU), and In-house Doctor Department. Key parameters were anti-CMV IgG and IgM, CMV PCR of urine, and clinically relevant symptoms caused by CMV. Between 46 and 52% of women of childbearing age were CMV seronegative. The prevalence of clinically relevant cCMV infection was between 0.008 and 0.04%. The CMV seronegativity rate of women of childbearing age was confirmed to be in the middle range of estimated data from other sources in Germany. Data from the NICU, SPC, NHS, and MMC show the prevalence of clinically relevant cCMV infection. The risk of all cCMV infections is underestimated. Thus, the true prevalence of clinically relevant and subclinical cCMV infections is >0.04%.

  11. Are We Underestimating Microplastic Contamination in Aquatic Environments?

    Science.gov (United States)

    Conkle, Jeremy L.; Báez Del Valle, Christian D.; Turner, Jeffrey W.

    2018-01-01

    Plastic debris, specifically microplastic in the aquatic environment, is an escalating environmental crisis. Efforts at national scales to reduce or ban microplastics in personal care products are starting to pay off, but this will not affect those materials already in the environment or those that result from unregulated products and materials. To better inform future microplastic research and mitigation efforts this study (1) evaluates methods currently used to quantify microplastics in the environment and (2) characterizes the concentration and size distribution of microplastics in a variety of products. In this study, 50 published aquatic surveys were reviewed and they demonstrated that most ( 80%) only account for plastics ≥ 300 μm in diameter. In addition, we surveyed 770 personal care products to determine the occurrence, concentration and size distribution of polyethylene microbeads. Particle concentrations ranged from 1.9 to 71.9 mg g-1 of product or 1649 to 31,266 particles g-1 of product. The large majority ( > 95%) of particles in products surveyed were less than the 300 μm minimum diameter, indicating that previous environmental surveys could be underestimating microplastic contamination. To account for smaller particles as well as microfibers from synthetic textiles, we strongly recommend that future surveys consider methods that materials < 300 μm in diameter.

  12. Confounding environmental colour and distribution shape leads to underestimation of population extinction risk.

    Directory of Open Access Journals (Sweden)

    Mike S Fowler

    Full Text Available The colour of environmental variability influences the size of population fluctuations when filtered through density dependent dynamics, driving extinction risk through dynamical resonance. Slow fluctuations (low frequencies dominate in red environments, rapid fluctuations (high frequencies in blue environments and white environments are purely random (no frequencies dominate. Two methods are commonly employed to generate the coloured spatial and/or temporal stochastic (environmental series used in combination with population (dynamical feedback models: autoregressive [AR(1] and sinusoidal (1/f models. We show that changing environmental colour from white to red with 1/f models, and from white to red or blue with AR(1 models, generates coloured environmental series that are not normally distributed at finite time-scales, potentially confounding comparison with normally distributed white noise models. Increasing variability of sample Skewness and Kurtosis and decreasing mean Kurtosis of these series alter the frequency distribution shape of the realised values of the coloured stochastic processes. These changes in distribution shape alter patterns in the probability of single and series of extreme conditions. We show that the reduced extinction risk for undercompensating (slow growing populations in red environments previously predicted with traditional 1/f methods is an artefact of changes in the distribution shapes of the environmental series. This is demonstrated by comparison with coloured series controlled to be normally distributed using spectral mimicry. Changes in the distribution shape that arise using traditional methods lead to underestimation of extinction risk in normally distributed, red 1/f environments. AR(1 methods also underestimate extinction risks in traditionally generated red environments. This work synthesises previous results and provides further insight into the processes driving extinction risk in model populations. We

  13. Systematic Methods and Tools for Computer Aided Modelling

    OpenAIRE

    Fedorova, Marina; Gani, Rafiqul; Sin, Gürkan

    2015-01-01

    Modeller spiller vigtige roller til design og analyse af kemi- og biokemibaserede produkter samt til processerne, der fremstille dem. Modelbaserede metoder og værktøjer har potentialet til at formindske antallet af eksperimenter, som kan være dyre og tidskrævende, og til at udvælge kandidater, hvorpå den eksperimentelle indsats bør fokuseres. I dette projekt blev en generel modelleringsramme udviklet til en systematisk modelopsætning ved hjælp af modelskabeloner. Modelrammen understøtter en n...

  14. Understanding in vivo modelling of depression in non-human animals: a systematic review protocol

    DEFF Research Database (Denmark)

    Bannach-Brown, Alexandra; Liao, Jing; Wegener, Gregers

    2016-01-01

    experimental model(s) to induce or mimic a depressive-like phenotype. Data that will be extracted include the model or method of induction; species and gender of the animals used; the behavioural, anatomical, electrophysiological, neurochemical or genetic outcome measure(s) used; risk of bias......The aim of this study is to systematically collect all published preclinical non-human animal literature on depression to provide an unbiased overview of existing knowledge. A systematic search will be carried out in PubMed and Embase. Studies will be included if they use non-human animal......-analysis of the preclinical studies modelling depression-like behaviours and phenotypes in animals....

  15. A Systematic Approach to Modelling Change Processes in Construction Projects

    Directory of Open Access Journals (Sweden)

    Ibrahim Motawa

    2012-11-01

    Full Text Available Modelling change processes within construction projects isessential to implement changes efficiently. Incomplete informationon the project variables at the early stages of projects leads toinadequate knowledge of future states and imprecision arisingfrom ambiguity in project parameters. This lack of knowledge isconsidered among the main source of changes in construction.Change identification and evaluation, in addition to predictingits impacts on project parameters, can help in minimising thedisruptive effects of changes. This paper presents a systematicapproach to modelling change process within construction projectsthat helps improve change identification and evaluation. Theapproach represents the key decisions required to implementchanges. The requirements of an effective change processare presented first. The variables defined for efficient changeassessment and diagnosis are then presented. Assessmentof construction changes requires an analysis for the projectcharacteristics that lead to change and also analysis of therelationship between the change causes and effects. The paperconcludes that, at the early stages of a project, projects with a highlikelihood of change occurrence should have a control mechanismover the project characteristics that have high influence on theproject. It also concludes, for the relationship between changecauses and effects, the multiple causes of change should bemodelled in a way to enable evaluating the change effects moreaccurately. The proposed approach is the framework for tacklingsuch conclusions and can be used for evaluating change casesdepending on the available information at the early stages ofconstruction projects.

  16. Effects of Photobiomodulation Therapy on Oxidative Stress in Muscle Injury Animal Models: A Systematic Review

    OpenAIRE

    dos Santos, Solange Almeida; Serra, Andrey Jorge; Stancker, Tatiane Garcia; Simões, Maíra Cecília Brandão; dos Santos Vieira, Marcia Ataíze; Leal-Junior, Ernesto Cesar; Prokic, Marko; Vasconsuelo, Andrea; Santos, Simone Silva; de Carvalho, Paulo de Tarso Camillo

    2017-01-01

    This systematic review was performed to identify the role of photobiomodulation therapy on experimental muscle injury models linked to induce oxidative stress. EMBASE, PubMed, and CINAHL were searched for studies published from January 2006 to January 2016 in the areas of laser and oxidative stress. Any animal model using photobiomodulation therapy to modulate oxidative stress was included in analysis. Eight studies were selected from 68 original articles targeted on laser irradiation and oxi...

  17. Decision modelling of non-pharmacological interventions for individuals with dementia: a systematic review of methodologies

    DEFF Research Database (Denmark)

    Sopina, Liza; Sørensen, Jan

    2018-01-01

    Abstract Objectives: The main objective of this study is to conduct a systematic review to identify and discuss methodological issues surrounding decision modelling for economic evaluation of non-pharmacological interventions (NPIs) in dementia. Methods: A systematic search was conducted for publ......Abstract Objectives: The main objective of this study is to conduct a systematic review to identify and discuss methodological issues surrounding decision modelling for economic evaluation of non-pharmacological interventions (NPIs) in dementia. Methods: A systematic search was conducted...... of challenging methodological issues were identified, including the use of MMSE-score as the main outcome measure, limited number of strategies compared, restricted time horizons, and limited or dated data on dementia onset, progression and mortality. Only one of the three tertiary prevention studies explicitly...... impact of NPIs for dementia in future decision models. It is also important to account for the effects of pharmacological therapies alongside the NPIs in economic evaluations. Access to more localised and up-to-date data on dementia onset, progression and mortality is a priority for accurate prediction....

  18. The role of underestimating body size for self-esteem and self-efficacy among grade five children in Canada.

    Science.gov (United States)

    Maximova, Katerina; Khan, Mohammad K A; Austin, S Bryn; Kirk, Sara F L; Veugelers, Paul J

    2015-10-01

    Underestimating body size hinders healthy behavior modification needed to prevent obesity. However, initiatives to improve body size misperceptions may have detrimental consequences on self-esteem and self-efficacy. Using sex-specific multiple mixed-effect logistic regression models, we examined the association of underestimating versus accurate body size perceptions with self-esteem and self-efficacy in a provincially representative sample of 5075 grade five school children. Body size perceptions were defined as the standardized difference between the body mass index (BMI, from measured height and weight) and self-perceived body size (Stunkard body rating scale). Self-esteem and self-efficacy for physical activity and healthy eating were self-reported. Most of overweight boys and girls (91% and 83%); and most of obese boys and girls (93% and 90%) underestimated body size. Underestimating weight was associated with greater self-efficacy for physical activity and healthy eating among normal-weight children (odds ratio: 1.9 and 1.6 for boys, 1.5 and 1.4 for girls) and greater self-esteem among overweight and obese children (odds ratio: 2.0 and 6.2 for boys, 2.0 and 3.4 for girls). Results highlight the importance of developing optimal intervention strategies as part of targeted obesity prevention efforts that de-emphasize the focus on body weight, while improving body size perceptions. Copyright © 2015 Elsevier Inc. All rights reserved.

  19. Predictive equations underestimate resting energy expenditure in female adolescents with phenylketonuria

    Science.gov (United States)

    Quirk, Meghan E.; Schmotzer, Brian J.; Schmotzer, Brian J.; Singh, Rani H.

    2010-01-01

    Resting energy expenditure (REE) is often used to estimate total energy needs. The Schofield equation based on weight and height has been reported to underestimate REE in female children with phenylketonuria (PKU). The objective of this observational, cross-sectional study was to evaluate the agreement of measured REE with predicted REE for female adolescents with PKU. A total of 36 females (aged 11.5-18.7 years) with PKU attending Emory University’s Metabolic Camp (June 2002 – June 2008) underwent indirect calorimetry. Measured REE was compared to six predictive equations using paired Student’s t-tests, regression-based analysis, and assessment of clinical accuracy. The differences between measured and predicted REE were modeled against clinical parameters to determine to if a relationship existed. All six selected equations significantly under predicted measured REE (P< 0.005). The Schofield equation based on weight had the greatest level of agreement, with the lowest mean prediction bias (144 kcal) and highest concordance correlation coefficient (0.626). However, the Schofield equation based on weight lacked clinical accuracy, predicting measured REE within ±10% in only 14 of 36 participants. Clinical parameters were not associated with bias for any of the equations. Predictive equations underestimated measured REE in this group of female adolescents with PKU. Currently, there is no accurate and precise alternative for indirect calorimetry in this population. PMID:20497783

  20. Tundra water budget and implications of precipitation underestimation

    Science.gov (United States)

    Liljedahl, Anna K.; Hinzman, Larry D.; Kane, Douglas L.; Oechel, Walter C.; Tweedie, Craig E.; Zona, Donatella

    2017-08-01

    Difficulties in obtaining accurate precipitation measurements have limited meaningful hydrologic assessment for over a century due to performance challenges of conventional snowfall and rainfall gauges in windy environments. Here, we compare snowfall observations and bias adjusted snowfall to end-of-winter snow accumulation measurements on the ground for 16 years (1999-2014) and assess the implication of precipitation underestimation on the water balance for a low-gradient tundra wetland near Utqiagvik (formerly Barrow), Alaska (2007-2009). In agreement with other studies, and not accounting for sublimation, conventional snowfall gauges captured 23-56% of end-of-winter snow accumulation. Once snowfall and rainfall are bias adjusted, long-term annual precipitation estimates more than double (from 123 to 274 mm), highlighting the risk of studies using conventional or unadjusted precipitation that dramatically under-represent water balance components. Applying conventional precipitation information to the water balance analysis produced consistent storage deficits (79 to 152 mm) that were all larger than the largest actual deficit (75 mm), which was observed in the unusually low rainfall summer of 2007. Year-to-year variability in adjusted rainfall (±33 mm) was larger than evapotranspiration (±13 mm). Measured interannual variability in partitioning of snow into runoff (29% in 2008 to 68% in 2009) in years with similar end-of-winter snow accumulation (180 and 164 mm, respectively) highlights the importance of the previous summer's rainfall (25 and 60 mm, respectively) on spring runoff production. Incorrect representation of precipitation can therefore have major implications for Arctic water budget descriptions that in turn can alter estimates of carbon and energy fluxes.

  1. THE TEXTBOOK AS A PRODUCT OF SCHOOL GEOGRAPHY: underestimated work?

    Directory of Open Access Journals (Sweden)

    José Eustáquio de Sene

    2014-01-01

    Full Text Available ABSTRACT: This article will address the textbook as a specific cultural production of school disciplines having as reference the theoretical debate that opposed the conceptions of "didactic transposition" (CHEVALLARD, 1997 and "school culture" (CHERVEL, 1990. Based on this debate, characteristic of the curriculum field, this article aims to understand why, historically, the textbook has been underestimated and even considered a "less important work” within the limits of the academy (BITTENCOURT, 2004. The examples used will always be of the Geography discipline – both school and academic, as well as the relations between this two fields – having in mind their "multiplicity of paradigms" (LESTEGÁS, 2002. The analysis will also take into account the historic process of institutionalization of academic Geography based on "Layton’s stages" (GOODSON, 2005. RESUMO: Este artigo abordará o livro didático como uma produção cultural específica das disciplinas escolares tendo como referência o debate teórico que opõem as concepções de “transposição didática” (CHEVALLARD, 1997 e de “cultura escolar” (CHERVEL, 1990. Com base em tal debate, próprio do campo curricular, procurará compreender porque historicamente o livro didático tem sido pouco valorizado e até mesmo considerado uma “obra menor” nos limites da academia (BITTENCOURT, 2004. Os exemplos utilizados serão sempre da disciplina Geografia – tanto a escolar quanto a acadêmica, assim como das relações entre ambas – tendo em vista sua “multiplicidade de paradigmas” (LESTEGÁS, 2002. A análise também levará em conta o histórico processo de institucionalização da Geografia acadêmica com base nos “estágios de Layton” (GOODSON, 2005.

  2. Scaling analysis in modeling transport and reaction processes a systematic approach to model building and the art of approximation

    CERN Document Server

    Krantz, William B

    2007-01-01

    This book is unique as the first effort to expound on the subject of systematic scaling analysis. Not written for a specific discipline, the book targets any reader interested in transport phenomena and reaction processes. The book is logically divided into chapters on the use of systematic scaling analysis in fluid dynamics, heat transfer, mass transfer, and reaction processes. An integrating chapter is included that considers more complex problems involving combined transport phenomena. Each chapter includes several problems that are explained in considerable detail. These are followed by several worked examples for which the general outline for the scaling is given. Each chapter also includes many practice problems. This book is based on recognizing the value of systematic scaling analysis as a pedagogical method for teaching transport and reaction processes and as a research tool for developing and solving models and in designing experiments. Thus, the book can serve as both a textbook and a reference boo...

  3. Simulation Modelling in Healthcare: An Umbrella Review of Systematic Literature Reviews.

    Science.gov (United States)

    Salleh, Syed; Thokala, Praveen; Brennan, Alan; Hughes, Ruby; Booth, Andrew

    2017-09-01

    Numerous studies examine simulation modelling in healthcare. These studies present a bewildering array of simulation techniques and applications, making it challenging to characterise the literature. The aim of this paper is to provide an overview of the level of activity of simulation modelling in healthcare and the key themes. We performed an umbrella review of systematic literature reviews of simulation modelling in healthcare. Searches were conducted of academic databases (JSTOR, Scopus, PubMed, IEEE, SAGE, ACM, Wiley Online Library, ScienceDirect) and grey literature sources, enhanced by citation searches. The articles were included if they performed a systematic review of simulation modelling techniques in healthcare. After quality assessment of all included articles, data were extracted on numbers of studies included in each review, types of applications, techniques used for simulation modelling, data sources and simulation software. The search strategy yielded a total of 117 potential articles. Following sifting, 37 heterogeneous reviews were included. Most reviews achieved moderate quality rating on a modified AMSTAR (A Measurement Tool used to Assess systematic Reviews) checklist. All the review articles described the types of applications used for simulation modelling; 15 reviews described techniques used for simulation modelling; three reviews described data sources used for simulation modelling; and six reviews described software used for simulation modelling. The remaining reviews either did not report or did not provide enough detail for the data to be extracted. Simulation modelling techniques have been used for a wide range of applications in healthcare, with a variety of software tools and data sources. The number of reviews published in recent years suggest an increased interest in simulation modelling in healthcare.

  4. Design of roundness measurement model with multi-systematic error for cylindrical components with large radius.

    Science.gov (United States)

    Sun, Chuanzhi; Wang, Lei; Tan, Jiubin; Zhao, Bo; Tang, Yangchao

    2016-02-01

    The paper designs a roundness measurement model with multi-systematic error, which takes eccentricity, probe offset, radius of tip head of probe, and tilt error into account for roundness measurement of cylindrical components. The effects of the systematic errors and radius of components are analysed in the roundness measurement. The proposed method is built on the instrument with a high precision rotating spindle. The effectiveness of the proposed method is verified by experiment with the standard cylindrical component, which is measured on a roundness measuring machine. Compared to the traditional limacon measurement model, the accuracy of roundness measurement can be increased by about 2.2 μm using the proposed roundness measurement model for the object with a large radius of around 37 mm. The proposed method can improve the accuracy of roundness measurement and can be used for error separation, calibration, and comparison, especially for cylindrical components with a large radius.

  5. Complete Systematic Error Model of SSR for Sensor Registration in ATC Surveillance Networks.

    Science.gov (United States)

    Jarama, Ángel J; López-Araquistain, Jaime; Miguel, Gonzalo de; Besada, Juan A

    2017-09-21

    In this paper, a complete and rigorous mathematical model for secondary surveillance radar systematic errors (biases) is developed. The model takes into account the physical effects systematically affecting the measurement processes. The azimuth biases are calculated from the physical error of the antenna calibration and the errors of the angle determination dispositive. Distance bias is calculated from the delay of the signal produced by the refractivity index of the atmosphere, and from clock errors, while the altitude bias is calculated taking into account the atmosphere conditions (pressure and temperature). It will be shown, using simulated and real data, that adapting a classical bias estimation process to use the complete parametrized model results in improved accuracy in the bias estimation.

  6. Systematic Multi‐Scale Model Development Strategy for the Fragrance Spraying Process and Transport

    DEFF Research Database (Denmark)

    Heitzig, M.; Rong, Y.; Gregson, C.

    2012-01-01

    The fast and efficient development and application of reliable models with appropriate degree of detail to predict the behavior of fragrance aerosols are challenging problems of high interest to the related industries. A generic modeling template for the systematic derivation of specific fragrance...... aerosol models is proposed. The main benefits of the fragrance spraying template are the speed‐up of the model development/derivation process, the increase in model quality, and the provision of structured domain knowledge where needed. The fragrance spraying template is integrated in a generic computer......‐aided modeling framework, which is structured based on workflows for different general modeling tasks. The benefits of the fragrance spraying template are highlighted by a case study related to the derivation of a fragrance aerosol model that is able to reflect measured dynamic droplet size distribution profiles...

  7. Systematic errors in temperature estimates from MODIS data covering the western Palearctic and their impact on a parasite development model

    Directory of Open Access Journals (Sweden)

    Jorge Alonso-Carné

    2013-11-01

    Full Text Available The modelling of habitat suitability for parasites is a growing area of research due to its association with climate change and ensuing shifts in the distribution of infectious diseases. Such models depend on remote sensing data and require accurate, high-resolution temperature measurements. The temperature is critical for accurate estimation of development rates and potential habitat ranges for a given parasite. The MODIS sensors aboard the Aqua and Terra satellites provide high-resolution temperature data for remote sensing applications. This paper describes comparative analysis of MODISderived temperatures relative to ground records of surface temperature in the western Palaearctic. The results show that MODIS overestimated maximum temperature values and underestimated minimum temperatures by up to 5-6 ºC. The combined use of both Aqua and Terra datasets provided the most accurate temperature estimates around latitude 35-44º N, with an overestimation during spring-summer months and an underestimation in autumn-winter. Errors in temperature estimation were associated with specific ecological regions within the target area as well as technical limitations in the temporal and orbital coverage of the satellites (e.g. sensor limitations and satellite transit times. We estimated error propagation of temperature uncertainties in parasite habitat suitability models by comparing outcomes of published models. Error estimates reached 36% of annual respective measurements depending on the model used. Our analysis demonstrates the importance of adequate image processing and points out the limitations of MODIS temperature data as inputs into predictive models concerning parasite lifecycles.

  8. Asymmetries of poverty: why global burden of disease valuations underestimate the burden of neglected tropical diseases.

    Directory of Open Access Journals (Sweden)

    Charles H King

    2008-03-01

    Full Text Available The disability-adjusted life year (DALY initially appeared attractive as a health metric in the Global Burden of Disease (GBD program, as it purports to be a comprehensive health assessment that encompassed premature mortality, morbidity, impairment, and disability. It was originally thought that the DALY would be useful in policy settings, reflecting normative valuations as a standardized unit of ill health. However, the design of the DALY and its use in policy estimates contain inherent flaws that result in systematic undervaluation of the importance of chronic diseases, such as many of the neglected tropical diseases (NTDs, in world health. The conceptual design of the DALY comes out of a perspective largely focused on the individual risk rather than the ecology of disease, thus failing to acknowledge the implications of context on the burden of disease for the poor. It is nonrepresentative of the impact of poverty on disability, which results in the significant underestimation of disability weights for chronic diseases such as the NTDs. Finally, the application of the DALY in policy estimates does not account for the nonlinear effects of poverty in the cost-utility analysis of disease control, effectively discounting the utility of comprehensively treating NTDs. The present DALY framework needs to be substantially revised if the GBD is to become a valid and useful system for determining health priorities.

  9. Asymmetries of poverty: why global burden of disease valuations underestimate the burden of neglected tropical diseases.

    Science.gov (United States)

    King, Charles H; Bertino, Anne-Marie

    2008-03-26

    The disability-adjusted life year (DALY) initially appeared attractive as a health metric in the Global Burden of Disease (GBD) program, as it purports to be a comprehensive health assessment that encompassed premature mortality, morbidity, impairment, and disability. It was originally thought that the DALY would be useful in policy settings, reflecting normative valuations as a standardized unit of ill health. However, the design of the DALY and its use in policy estimates contain inherent flaws that result in systematic undervaluation of the importance of chronic diseases, such as many of the neglected tropical diseases (NTDs), in world health. The conceptual design of the DALY comes out of a perspective largely focused on the individual risk rather than the ecology of disease, thus failing to acknowledge the implications of context on the burden of disease for the poor. It is nonrepresentative of the impact of poverty on disability, which results in the significant underestimation of disability weights for chronic diseases such as the NTDs. Finally, the application of the DALY in policy estimates does not account for the nonlinear effects of poverty in the cost-utility analysis of disease control, effectively discounting the utility of comprehensively treating NTDs. The present DALY framework needs to be substantially revised if the GBD is to become a valid and useful system for determining health priorities.

  10. FROM ATOMISTIC TO SYSTEMATIC COARSE-GRAINED MODELS FOR MOLECULAR SYSTEMS

    KAUST Repository

    Harmandaris, Vagelis

    2017-10-03

    The development of systematic (rigorous) coarse-grained mesoscopic models for complex molecular systems is an intense research area. Here we first give an overview of methods for obtaining optimal parametrized coarse-grained models, starting from detailed atomistic representation for high dimensional molecular systems. Different methods are described based on (a) structural properties (inverse Boltzmann approaches), (b) forces (force matching), and (c) path-space information (relative entropy). Next, we present a detailed investigation concerning the application of these methods in systems under equilibrium and non-equilibrium conditions. Finally, we present results from the application of these methods to model molecular systems.

  11. Systematic model development for partial nitrification of landfill leachate in a SBR

    DEFF Research Database (Denmark)

    Ganigue, R.; Volcke, E.I.P.; Puig, S.

    2010-01-01

    This study deals with partial nitrification in a sequencing batch reactor (PN-SBR) treating raw urban landfill leachate. In order to enhance process insight (e.g. quantify interactions between aeration, CO2 stripping, alkalinity, pH, nitrification kinetics), a mathematical model has been set up....... Following a systematic procedure, the model was successfully constructed, calibrated and validated using data from short-term (one cycle) operation of the PN-SBR. The evaluation of the model revealed a good fit to the main physical-chemical measurements (ammonium, nitrite, nitrate and inorganic carbon...

  12. Acute kidney injury following liver transplantation: a systematic review of published predictive models.

    Science.gov (United States)

    Caragata, R; Wyssusek, K H; Kruger, P

    2016-03-01

    Acute kidney injury is a frequent postoperative complication amongst liver transplant recipients and is associated with increased morbidity and mortality. This systematic review analysed the existing predictive models, in order to solidify current understanding. Articles were selected for inclusion if they described the primary development of a clinical prediction model (either an algorithm or risk score) to predict AKI post liver transplantation. The database search yielded a total of seven studies describing the primary development of a prediction model or risk score for the development of AKI following liver transplantation. The models span thirteen years of clinical research and highlight a gradual change in the definitions of AKI, emphasising the need to employ standardised definitions for subsequent studies. Collectively, the models identify a diverse range of predictive factors with several common trends. They emphasise the impact of preoperative renal dysfunction, liver disease severity and aetiology, metabolic risk factors as well as intraoperative variables including measures of haemodynamic instability and graft quality. Although several of the models address postoperative parameters, their utility in predictive modelling seems to be of questionable relevance. The common risk factors identified within this systematic review provide a minimum list of variables, which future studies should address. Research in this area would benefit from prospective, multi-site studies with larger cohorts as well as the subsequent internal and external validation of predictive models. Ultimately, the ability to identify patients at high risk of post-transplant AKI may enable early intervention and perhaps prevention.

  13. Decoding β-decay systematics: A global statistical model for β- half-lives

    International Nuclear Information System (INIS)

    Costiris, N. J.; Mavrommatis, E.; Gernoth, K. A.; Clark, J. W.

    2009-01-01

    Statistical modeling of nuclear data provides a novel approach to nuclear systematics complementary to established theoretical and phenomenological approaches based on quantum theory. Continuing previous studies in which global statistical modeling is pursued within the general framework of machine learning theory, we implement advances in training algorithms designed to improve generalization, in application to the problem of reproducing and predicting the half-lives of nuclear ground states that decay 100% by the β - mode. More specifically, fully connected, multilayer feed-forward artificial neural network models are developed using the Levenberg-Marquardt optimization algorithm together with Bayesian regularization and cross-validation. The predictive performance of models emerging from extensive computer experiments is compared with that of traditional microscopic and phenomenological models as well as with the performance of other learning systems, including earlier neural network models as well as the support vector machines recently applied to the same problem. In discussing the results, emphasis is placed on predictions for nuclei that are far from the stability line, and especially those involved in r-process nucleosynthesis. It is found that the new statistical models can match or even surpass the predictive performance of conventional models for β-decay systematics and accordingly should provide a valuable additional tool for exploring the expanding nuclear landscape.

  14. Comparison of two stochastic techniques for reliable urban runoff prediction by modeling systematic errors

    DEFF Research Database (Denmark)

    Del Giudice, Dario; Löwe, Roland; Madsen, Henrik

    2015-01-01

    In urban rainfall-runoff, commonly applied statistical techniques for uncertainty quantification mostly ignore systematic output errors originating from simplified models and erroneous inputs. Consequently, the resulting predictive uncertainty is often unreliable. Our objective is to present two ....... These properties make it more suitable for off-line applications. The IND can help in diagnosing the causes of output errors and is computationally inexpensive. It produces best results on short forecast horizons that are typical for online applications.......In urban rainfall-runoff, commonly applied statistical techniques for uncertainty quantification mostly ignore systematic output errors originating from simplified models and erroneous inputs. Consequently, the resulting predictive uncertainty is often unreliable. Our objective is to present two...

  15. Systematic Assessment of Neutron and Gamma Backgrounds Relevant to Operational Modeling and Detection Technology Implementation

    Energy Technology Data Exchange (ETDEWEB)

    Archer, Daniel E. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Hornback, Donald Eric [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Johnson, Jeffrey O. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Nicholson, Andrew D. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Patton, Bruce W. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Peplow, Douglas E. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Miller, Thomas Martin [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Ayaz-Maierhafer, Birsen [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-01-01

    This report summarizes the findings of a two year effort to systematically assess neutron and gamma backgrounds relevant to operational modeling and detection technology implementation. The first year effort focused on reviewing the origins of background sources and their impact on measured rates in operational scenarios of interest. The second year has focused on the assessment of detector and algorithm performance as they pertain to operational requirements against the various background sources and background levels.

  16. Evaluation models and criteria of the quality of hospital websites: a systematic review study

    OpenAIRE

    Jeddi, Fatemeh Rangraz; Gilasi, Hamidreza; Khademi, Sahar

    2017-01-01

    Introduction Hospital websites are important tools in establishing communication and exchanging information between patients and staff, and thus should enjoy an acceptable level of quality. The aim of this study was to identify proper models and criteria to evaluate the quality of hospital websites. Methods This research was a systematic review study. The international databases such as Science Direct, Google Scholar, PubMed, Proquest, Ovid, Elsevier, Springer, and EBSCO together with regiona...

  17. Minimal Requirements for Primary HIV Latency Models Based on a Systematic Review.

    Science.gov (United States)

    Bonczkowski, Pawel; De Scheerder, Marie-Angélique; De Spiegelaere, Ward; Vandekerckhove, Linos

    2016-01-01

    Due to the scarcity of HIV-1 latently infected cells in patients, in vitro primary latency models are now commonly used to study the HIV-1 reservoir. To this end, a number of experimental systems have been developed. Most of these models differ based on the nature of the primary CD4+ T-cell type, the used HIV strains, activation methods, and latency assessment strategies. Despite these differences, most models share some common characteristics. Here, we provide a systematic review covering the primary HIV latency models that have been used to date with the aim to compare these models and identify minimal requirements for such experiments. A systematic search on PubMed and Web of Science databases generated a short list of 17 unique publications that propose new in vitro latency models. Based on the described methods, we propose and discuss a generalized workflow, visualizing all the necessary steps to perform such an in vitro study, with the key choices and validation steps that need to be made; from cell type selection until the model readout.

  18. Surgeons underestimate their influence on medical students entering surgery.

    NARCIS (Netherlands)

    Quillin 3rd, R.C.; Pritts, T.A.; Davis, B.R.; Hanseman, D.; Collins, J.M.; Athota, K.P.; Edwards, M.J.R.; Tevar, A.D.

    2012-01-01

    BACKGROUND: Positive surgical role models influence medical students to pursue a career in surgery. However, the perception by role models of their own effectiveness has yet to be examined. In this study, we evaluated the influence of surgical role models on medical student career choice, and how

  19. Mathematical Modeling in Tobacco Control Research: Initial Results From a Systematic Review.

    Science.gov (United States)

    Feirman, Shari P; Donaldson, Elisabeth; Glasser, Allison M; Pearson, Jennifer L; Niaura, Ray; Rose, Shyanika W; Abrams, David B; Villanti, Andrea C

    2016-03-01

    The US Food and Drug Administration has expressed interest in using mathematical models to evaluate potential tobacco policies. The goal of this systematic review was to synthesize data from tobacco control studies that employ mathematical models. We searched five electronic databases on July 1, 2013 to identify published studies that used a mathematical model to project a tobacco-related outcome and developed a data extraction form based on the ISPOR-SMDM Modeling Good Research Practices. We developed an organizational framework to categorize these studies and identify models employed across multiple papers. We synthesized results qualitatively, providing a descriptive synthesis of included studies. The 263 studies in this review were heterogeneous with regard to their methodologies and aims. We used the organizational framework to categorize each study according to its objective and map the objective to a model outcome. We identified two types of study objectives (trend and policy/intervention) and three types of model outcomes (change in tobacco use behavior, change in tobacco-related morbidity or mortality, and economic impact). Eighteen models were used across 118 studies. This paper extends conventional systematic review methods to characterize a body of literature on mathematical modeling in tobacco control. The findings of this synthesis can inform the development of new models and the improvement of existing models, strengthening the ability of researchers to accurately project future tobacco-related trends and evaluate potential tobacco control policies and interventions. These findings can also help decision-makers to identify and become oriented with models relevant to their work. © The Author 2015. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  20. Coordinating the Provision of Health Services in Humanitarian Crises: a Systematic Review of Suggested Models.

    Science.gov (United States)

    Lotfi, Tamara; Bou-Karroum, Lama; Darzi, Andrea; Hajjar, Rayan; El Rahyel, Ahmed; El Eid, Jamale; Itani, Mira; Brax, Hneine; Akik, Chaza; Osman, Mona; Hassan, Ghayda; El-Jardali, Fadi; Akl, Elie

    2016-08-03

    Our objective was to identify published models of coordination between entities funding or delivering health services in humanitarian crises, whether the coordination took place during or after the crises. We included reports describing models of coordination in sufficient detail to allow reproducibility. We also included reports describing implementation of identified models, as case studies. We searched Medline, PubMed, EMBASE, Cochrane Central Register of Controlled Trials, CINAHL, PsycINFO, and the WHO Global Health Library. We also searched websites of relevant organizations. We followed standard systematic review methodology. Our search captured 14,309 citations. The screening process identified 34 eligible papers describing five models of coordination of delivering health services: the "Cluster Approach" (with 16 case studies), the 4Ws "Who is Where, When, doing What" mapping tool (with four case studies), the "Sphere Project" (with two case studies), the "5x5" model (with one case study), and the "model of information coordination" (with one case study). The 4Ws and the 5x5 focus on coordination of services for mental health, the remaining models do not focus on a specific health topic. The Cluster approach appears to be the most widely used. One case study was a mixed implementation of the Cluster approach and the Sphere model. We identified no model of coordination for funding of health service. This systematic review identified five proposed coordination models that have been implemented by entities funding or delivering health service in humanitarian crises. There is a need to compare the effect of these different models on outcomes such as availability of and access to health services.

  1. Economic Evaluations of Multicomponent Disease Management Programs with Markov Models: A Systematic Review.

    Science.gov (United States)

    Kirsch, Florian

    2016-12-01

    Disease management programs (DMPs) for chronic diseases are being increasingly implemented worldwide. To present a systematic overview of the economic effects of DMPs with Markov models. The quality of the models is assessed, the method by which the DMP intervention is incorporated into the model is examined, and the differences in the structure and data used in the models are considered. A literature search was conducted; the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement was followed to ensure systematic selection of the articles. Study characteristics e.g. results, the intensity of the DMP and usual care, model design, time horizon, discount rates, utility measures, and cost-of-illness were extracted from the reviewed studies. Model quality was assessed by two researchers with two different appraisals: one proposed by Philips et al. (Good practice guidelines for decision-analytic modelling in health technology assessment: a review and consolidation of quality asessment. Pharmacoeconomics 2006;24:355-71) and the other proposed by Caro et al. (Questionnaire to assess relevance and credibility of modeling studies for informing health care decision making: an ISPOR-AMCP-NPC Good Practice Task Force report. Value Health 2014;17:174-82). A total of 16 studies (9 on chronic heart disease, 2 on asthma, and 5 on diabetes) met the inclusion criteria. Five studies reported cost savings and 11 studies reported additional costs. In the quality, the overall score of the models ranged from 39% to 65%, it ranged from 34% to 52%. Eleven models integrated effectiveness derived from a clinical trial or a meta-analysis of complete DMPs and only five models combined intervention effects from different sources into a DMP. The main limitations of the models are bad reporting practice and the variation in the selection of input parameters. Eleven of the 14 studies reported cost-effectiveness results of less than $30,000 per quality-adjusted life-year and

  2. Primary Health Care Models Addressing Health Equity for Immigrants: A Systematic Scoping Review.

    Science.gov (United States)

    Batista, Ricardo; Pottie, Kevin; Bouchard, Louise; Ng, Edward; Tanuseputro, Peter; Tugwell, Peter

    2018-02-01

    To examine two healthcare models, specifically "Primary Medical Care" (PMC) and "Primary Health Care" (PHC) in the context of immigrant populations' health needs. We conducted a systematic scoping review of studies that examined primary care provided to immigrants. We categorized studies into two models, PMC and PHC. We used subjects of access barriers and preventive interventions to analyze the potential of PMC/PHC to address healthcare inequities. From 1385 articles, 39 relevant studies were identified. In the context of immigrant populations, the PMC model was found to be more oriented to implement strategies that improve quality of care of the acute and chronically ill, while PHC models focused more on health promotion and strategies to address cultural and access barriers to care, and preventive strategies to address social determinants of health. Primary Health Care models may be better equipped to address social determinants of health, and thus have more potential to reduce immigrant populations' health inequities.

  3. A Novel, Physics-Based Data Analytics Framework for Reducing Systematic Model Errors

    Science.gov (United States)

    Wu, W.; Liu, Y.; Vandenberghe, F. C.; Knievel, J. C.; Hacker, J.

    2015-12-01

    Most climate and weather models exhibit systematic biases, such as under predicted diurnal temperatures in the WRF (Weather Research and Forecasting) model. General approaches to alleviate the systematic biases include improving model physics and numerics, improving data assimilation, and bias correction through post-processing. In this study, we developed a novel, physics-based data analytics framework in post processing by taking advantage of ever-growing high-resolution (spatial and temporal) observational and modeling data. In the framework, a spatiotemporal PCA (Principal Component Analysis) is first applied on the observational data to filter out noise and information on scales that a model may not be able to resolve. The filtered observations are then used to establish regression relationships with archived model forecasts in the same spatiotemporal domain. The regressions along with the model forecasts predict the projected observations in the forecasting period. The pre-regression PCA procedure strengthens regressions, and enhances predictive skills. We then combine the projected observations with the past observations to apply PCA iteratively to derive the final forecasts. This post-regression PCA reconstructs variances and scales of information that are lost in the regression. The framework was examined and validated with 24 days of 5-minute observational data and archives from the WRF model at 27 stations near Dugway Proving Ground, Utah. The validation shows significant bias reduction in the diurnal cycle of predicted surface air temperature compared to the direct output from the WRF model. Additionally, unlike other post-processing bias correction schemes, the data analytics framework does not require long-term historic data and model archives. A week or two of the data is enough to take into account changes in weather regimes. The program, written in python, is also computationally efficient.

  4. Eating disorders among fashion models: a systematic review of the literature.

    Science.gov (United States)

    Zancu, Simona Alexandra; Enea, Violeta

    2017-09-01

    In the light of recent concerns regarding the eating disorders among fashion models and professional regulations of fashion model occupation, an examination of the scientific evidence on this issue is necessary. The article reviews findings on the prevalence of eating disorders and body image concerns among professional fashion models. A systematic literature search was conducted using ProQUEST, EBSCO, PsycINFO, SCOPUS, and Gale Canage electronic databases. A very low number of studies conducted on fashion models and eating disorders resulted between 1980 and 2015, with seven articles included in this review. Overall, results of these studies do not indicate a higher prevalence of eating disorders among fashion models compared to non-models. Fashion models have a positive body image and generally do not report more dysfunctional eating behaviors than controls. However, fashion models are on average slightly underweight with significantly lower BMI than controls, and give higher importance to appearance and thin body shape, and thus have a higher prevalence of partial-syndrome eating disorders than controls. Despite public concerns, research on eating disorders among professional fashion models is extremely scarce and results cannot be generalized to all models. The existing research fails to clarify the matter of eating disorders among fashion models and given the small number of studies, further research is needed.

  5. A comprehensive and systematic evaluation framework for a parsimonious daily rainfall field model

    Science.gov (United States)

    Bennett, Bree; Thyer, Mark; Leonard, Michael; Lambert, Martin; Bates, Bryson

    2018-01-01

    The spatial distribution of rainfall has a significant influence on catchment dynamics and the generation of streamflow time series. However, there are few stochastic models that can simulate long sequences of stochastic rainfall fields continuously in time and space. To address this issue, the first goal of this study was to present a new parsimonious stochastic model that produces daily rainfall fields across the catchment. To achieve parsimony, the model used the latent-variable approach (because this parsimoniously simulates rainfall occurrences as well as amounts) and several other assumptions (including contemporaneous and separable spatiotemporal covariance structures). The second goal was to develop a comprehensive and systematic evaluation (CASE) framework to identify model strengths and weaknesses. This included quantitative performance categorisation that provided a systematic, succinct and transparent method to assess and summarise model performance over a range of statistics, sites, scales and seasons. The model is demonstrated using a case study from the Onkaparinga catchment in South Australia. The model showed many strengths in reproducing the observed rainfall characteristics with the majority of statistics classified as either statistically indistinguishable from the observed or within 5% of the observed across the majority of sites and seasons. These included rainfall occurrences/amounts, wet/dry spell distributions, annual volumes/extremes and spatial patterns, which are important from a hydrological perspective. One of the few weaknesses of the model was that the total annual rainfall in dry years (lower 5%) was overestimated by 15% on average over all sites. An advantage of the CASE framework was that it was able to identify the source of this overestimation was poor representation of the annual variability of rainfall occurrences. Given the strengths of this continuous daily rainfall field model it has a range of potential hydrological

  6. A Model of Consultation in Prostate Cancer Care: Evidence From a Systematic Review.

    Science.gov (United States)

    Paterson, Catherine; Nabi, Ghulam

    There has been an evolution of various consultation models in the literature. Men affected by prostate cancer can experience a range of unmet supportive care needs. Thus, effective consultations are paramount in the delivery of supportive care to optimize tailored self-management plans at the individual level of need. The aim of this study is to critically appraise existing models of consultation and make recommendations for a model of consultation within the scope of clinical practice for prostate cancer care. A systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Statement Guidelines. Electronic databases were searched using a wide range of keywords and free text items to increase the sensitivity and inclusiveness of the searches. Findings were integrated in a narrative synthesis. A total of 1829 articles were retrieved and 17 papers were included. Beneficial features ranged across a number of models that included a person-centered consultation, shared management plans, and safety netting. None of the reviewed models of consultation are suitable for use in prostate cancer care because of a range of limitations and the clinical context in which models were developed. A Cancer Care Consultation Model was informed from critical appraisal of the evidence and expert clinical and service user comment. Further research is needed to empirically test consultation models in routine clinical practice, specifically for advanced cancer specialist nurses. The Prostate Cancer Model of Consultation can be used to structure clinical consultations to target self-management care plans at the individual level of need over the cancer care continuum.

  7. Systematic review and overview of health economic evaluation models in obesity prevention and therapy.

    Science.gov (United States)

    Schwander, Bjoern; Hiligsmann, Mickaël; Nuijten, Mark; Evers, Silvia

    2016-10-01

    Given the increasing clinical and economic burden of obesity, it is of major importance to identify cost-effective approaches for obesity management. Areas covered: This study aims to systematically review and compile an overview of published decision models for health economic assessments (HEA) in obesity, in order to summarize and compare their key characteristics as well as to identify, inform and guide future research. Of the 4,293 abstracts identified, 87 papers met our inclusion criteria. A wide range of different methodological approaches have been identified. Of the 87 papers, 69 (79%) applied unique /distinctive modelling approaches. Expert commentary: This wide range of approaches suggests the need to develop recommendations /minimal requirements for model-based HEA of obesity. In order to reach this long-term goal, further research is required. Valuable future research steps would be to investigate the predictiveness, validity and quality of the identified modelling approaches.

  8. In vitro biofilm models to study dental caries: a systematic review.

    Science.gov (United States)

    Maske, T T; van de Sande, F H; Arthur, R A; Huysmans, M C D N J M; Cenci, M S

    2017-09-01

    The aim of this systematic review is to characterize and discuss key methodological aspects of in vitro biofilm models for caries-related research and to verify the reproducibility and dose-response of models considering the response to anti-caries and/or antimicrobial substances. Inclusion criteria were divided into Part I (PI): an in vitro biofilm model that produces a cariogenic biofilm and/or caries-like lesions and allows pH fluctuations; and Part II (PII): models showing an effect of anti-caries and/or antimicrobial substances. Within PI, 72.9% consisted of dynamic biofilm models, while 27.1% consisted of batch models. Within PII, 75.5% corresponded to dynamic models, whereas 24.5% corresponded to batch models. Respectively, 20.4 and 14.3% of the studies reported dose-response validations and reproducibility, and 32.7% were classified as having a high risk of bias. Several in vitro biofilm models are available for caries-related research; however, most models lack validation by dose-response and reproducibility experiments for each proposed protocol.

  9. Systematic narrative review of decision frameworks to select the appropriate modelling approaches for health economic evaluations.

    Science.gov (United States)

    Tsoi, B; O'Reilly, D; Jegathisawaran, J; Tarride, J-E; Blackhouse, G; Goeree, R

    2015-06-17

    In constructing or appraising a health economic model, an early consideration is whether the modelling approach selected is appropriate for the given decision problem. Frameworks and taxonomies that distinguish between modelling approaches can help make this decision more systematic and this study aims to identify and compare the decision frameworks proposed to date on this topic area. A systematic review was conducted to identify frameworks from peer-reviewed and grey literature sources. The following databases were searched: OVID Medline and EMBASE; Wiley's Cochrane Library and Health Economic Evaluation Database; PubMed; and ProQuest. Eight decision frameworks were identified, each focused on a different set of modelling approaches and employing a different collection of selection criterion. The selection criteria can be categorized as either: (i) structural features (i.e. technical elements that are factual in nature) or (ii) practical considerations (i.e. context-dependent attributes). The most commonly mentioned structural features were population resolution (i.e. aggregate vs. individual) and interactivity (i.e. static vs. dynamic). Furthermore, understanding the needs of the end-users and stakeholders was frequently incorporated as a criterion within these frameworks. There is presently no universally-accepted framework for selecting an economic modelling approach. Rather, each highlights different criteria that may be of importance when determining whether a modelling approach is appropriate. Further discussion is thus necessary as the modelling approach selected will impact the validity of the underlying economic model and have downstream implications on its efficiency, transparency and relevance to decision-makers.

  10. A systematic literature review of open source software quality assessment models.

    Science.gov (United States)

    Adewumi, Adewole; Misra, Sanjay; Omoregbe, Nicholas; Crawford, Broderick; Soto, Ricardo

    2016-01-01

    Many open source software (OSS) quality assessment models are proposed and available in the literature. However, there is little or no adoption of these models in practice. In order to guide the formulation of newer models so they can be acceptable by practitioners, there is need for clear discrimination of the existing models based on their specific properties. Based on this, the aim of this study is to perform a systematic literature review to investigate the properties of the existing OSS quality assessment models by classifying them with respect to their quality characteristics, the methodology they use for assessment, and their domain of application so as to guide the formulation and development of newer models. Searches in IEEE Xplore, ACM, Science Direct, Springer and Google Search is performed so as to retrieve all relevant primary studies in this regard. Journal and conference papers between the year 2003 and 2015 were considered since the first known OSS quality model emerged in 2003. A total of 19 OSS quality assessment model papers were selected. To select these models we have developed assessment criteria to evaluate the quality of the existing studies. Quality assessment models are classified into five categories based on the quality characteristics they possess namely: single-attribute, rounded category, community-only attribute, non-community attribute as well as the non-quality in use models. Our study reflects that software selection based on hierarchical structures is found to be the most popular selection method in the existing OSS quality assessment models. Furthermore, we found that majority (47%) of the existing models do not specify any domain of application. In conclusion, our study will be a valuable contribution to the community and helps the quality assessment model developers in formulating newer models and also to the practitioners (software evaluators) in selecting suitable OSS in the midst of alternatives.

  11. Systematic iteration between model and methodology: A proposed approach to evaluating unintended consequences.

    Science.gov (United States)

    Morell, Jonathan A

    2017-09-18

    This article argues that evaluators could better deal with unintended consequences if they improved their methods of systematically and methodically combining empirical data collection and model building over the life cycle of an evaluation. This process would be helpful because it can increase the timespan from when the need for a change in methodology is first suspected to the time when the new element of the methodology is operational. The article begins with an explanation of why logic models are so important in evaluation, and why the utility of models is limited if they are not continually revised based on empirical evaluation data. It sets the argument within the larger context of the value and limitations of models in the scientific enterprise. Following will be a discussion of various issues that are relevant to model development and revision. What is the relevance of complex system behavior for understanding predictable and unpredictable unintended consequences, and the methods needed to deal with them? How might understanding of unintended consequences be improved with an appreciation of generic patterns of change that are independent of any particular program or change effort? What are the social and organizational dynamics that make it rational and adaptive to design programs around single-outcome solutions to multi-dimensional problems? How does cognitive bias affect our ability to identify likely program outcomes? Why is it hard to discern change as a result of programs being embedded in multi-component, continually fluctuating, settings? The last part of the paper outlines a process for actualizing systematic iteration between model and methodology, and concludes with a set of research questions that speak to how the model/data process can be made efficient and effective. Copyright © 2017. Published by Elsevier Ltd.

  12. Systematical calculation of α decay half-lives with a generalized liquid drop model

    Energy Technology Data Exchange (ETDEWEB)

    Bao, Xiaojun [School of Nuclear Science and Technology, Lanzhou University, Lanzhou 730000 (China); Zhang, Hongfei, E-mail: zhanghongfei@lzu.edu.cn [School of Nuclear Science and Technology, Lanzhou University, Lanzhou 730000 (China); Zhang, Haifei [School of Nuclear Science and Technology, Lanzhou University, Lanzhou 730000 (China); Royer, G. [Laboratoire Subatech, UMR, IN2P3/CNRS, Université – Ecole des Mines, 44 Nantes (France); Li, Junqing [School of Nuclear Science and Technology, Lanzhou University, Lanzhou 730000 (China); Institute of Modern Physics, Chinese Academy of Science, Lanzhou 730000 (China)

    2014-01-15

    A systematic calculation of α decay half-lives is presented for even–even nuclei between Te and Z=118 isotopes. The potential energy governing α decay has been determined within a liquid drop model including proximity effects between the α particle and the daughter nucleus and taking into account the experimental Q value. The α decay half-lives have been deduced from the WKB barrier penetration probability. The α decay half-lives obtained agree reasonably well with the experimental data.

  13. Systematic Wind Farm Measurement Data Filtering Tool for Wake Model Calibration

    DEFF Research Database (Denmark)

    Rethore, Pierre-Elouan Mikael; Johansen, Nicholas Alan; Frandsen, Sten Tronæs

    A set of systematic methods for characterizing the sensors of a wind farm and using these sensors to filter more accurately large volumes of measurement data is proposed. These methods are based on the experience accumulated while processing datasets from two large offshore wind farms in Denmark....... Both wake model developers and wind farm operators seeking to determine how the wind farm operates under specific conditions can find these methods valuable. The methods are general and can be applied successfully to any wind farm by taking into consideration the specific aspects of each wind farm....

  14. Physical activity: an underestimated investment in human capital?

    Science.gov (United States)

    Bailey, Richard; Hillman, Charles; Arent, Shawn; Petitpas, Albert

    2013-03-01

    Despite the fact that physical activity is universally acknowledged to be an important part of healthy functioning and well-being, the full scope of its value is rarely appreciated. This article introduces a novel framework for understanding the relationships between physical activity (and specifically sport-related forms of physical activity) and different aspects of human development. It proposes that the outcomes of physical activity can be framed as differential 'capitals' that represent investments in domain-specific assets: Emotional, Financial, Individual, Intellectual, Physical, and Social. These investments, especially when made early in the life course, can yield significant rewards, both at that time and for years to come. The paper presents a new model-the Human Capital Model-that makes sense of these effects, outlines the different capitals, and briefly articulates the conditions necessary for the realization of Human Capital growth through physical activity.

  15. Dynamic epidemiological models for dengue transmission: a systematic review of structural approaches.

    Directory of Open Access Journals (Sweden)

    Mathieu Andraud

    Full Text Available Dengue is a vector-borne disease recognized as the major arbovirose with four immunologically distant dengue serotypes coexisting in many endemic areas. Several mathematical models have been developed to understand the transmission dynamics of dengue, including the role of cross-reactive antibodies for the four different dengue serotypes. We aimed to review deterministic models of dengue transmission, in order to summarize the evolution of insights for, and provided by, such models, and to identify important characteristics for future model development. We identified relevant publications using PubMed and ISI Web of Knowledge, focusing on mathematical deterministic models of dengue transmission. Model assumptions were systematically extracted from each reviewed model structure, and were linked with their underlying epidemiological concepts. After defining common terms in vector-borne disease modelling, we generally categorised fourty-two published models of interest into single serotype and multiserotype models. The multi-serotype models assumed either vector-host or direct host-to-host transmission (ignoring the vector component. For each approach, we discussed the underlying structural and parameter assumptions, threshold behaviour and the projected impact of interventions. In view of the expected availability of dengue vaccines, modelling approaches will increasingly focus on the effectiveness and cost-effectiveness of vaccination options. For this purpose, the level of representation of the vector and host populations seems pivotal. Since vector-host transmission models would be required for projections of combined vaccination and vector control interventions, we advocate their use as most relevant to advice health policy in the future. The limited understanding of the factors which influence dengue transmission as well as limited data availability remain important concerns when applying dengue models to real-world decision problems.

  16. Systematic model for lean product development implementation in an automotive related company

    Directory of Open Access Journals (Sweden)

    Daniel Osezua Aikhuele

    2017-07-01

    Full Text Available Lean product development is a major innovative business strategy that employs sets of practices to achieve an efficient, innovative and a sustainable product development. Despite the many benefits and high hopes in the lean strategy, many companies are still struggling, and unable to either achieve or sustain substantial positive results with their lean implementation efforts. However, as the first step towards addressing this issue, this paper seeks to propose a systematic model that considers the administrative and implementation limitations of lean thinking practices in the product development process. The model which is based on the integration of fuzzy Shannon’s entropy and Modified Technique for Order Preference by Similarity to the Ideal Solution (M-TOPSIS model for the lean product development practices implementation with respective to different criteria including management and leadership, financial capabilities, skills and expertise and organization culture, provides a guide or roadmap for product development managers on the lean implementation route.

  17. [Model for the systematic classification of outcomes in health promotion and prevention].

    Science.gov (United States)

    Cloetta, Bernhard; Spencer, Brenda; Spörri, Adrian; Ruckstuhl, Brigitte; Broesskamp-Stone, Ursel; Ackermann, Günter

    2005-01-01

    Successful demonstration of the effects of health promotion calls for systematic documentation and comparison of the outcome of different measures and projects. A model has been developed in the form of an outcome categorisation system for this purpose and is presented here. The model includes four categories covering the intermediate outcomes of health promotion measures, and three categories for outcomes at the level of health determinants (conditions necessary for health). Each category includes three to four sub-categories, for which examples of possible indicators are presented. The model can be applied both in the planning and in the evaluation stage of a project. This makes it possible for health promotion agencies and institutions responsible for funding and promotion to obtain a general overview of the outcome of their work.

  18. Risk Prediction Models for Incident Heart Failure: A Systematic Review of Methodology and Model Performance.

    Science.gov (United States)

    Sahle, Berhe W; Owen, Alice J; Chin, Ken Lee; Reid, Christopher M

    2017-09-01

    Numerous models predicting the risk of incident heart failure (HF) have been developed; however, evidence of their methodological rigor and reporting remains unclear. This study critically appraises the methods underpinning incident HF risk prediction models. EMBASE and PubMed were searched for articles published between 1990 and June 2016 that reported at least 1 multivariable model for prediction of HF. Model development information, including study design, variable coding, missing data, and predictor selection, was extracted. Nineteen studies reporting 40 risk prediction models were included. Existing models have acceptable discriminative ability (C-statistics > 0.70), although only 6 models were externally validated. Candidate variable selection was based on statistical significance from a univariate screening in 11 models, whereas it was unclear in 12 models. Continuous predictors were retained in 16 models, whereas it was unclear how continuous variables were handled in 16 models. Missing values were excluded in 19 of 23 models that reported missing data, and the number of events per variable was models. Only 2 models presented recommended regression equations. There was significant heterogeneity in discriminative ability of models with respect to age (P prediction models that had sufficient discriminative ability, although few are externally validated. Methods not recommended for the conduct and reporting of risk prediction modeling were frequently used, and resulting algorithms should be applied with caution. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Satellite data for systematic validation of wave model results in the Black Sea

    Science.gov (United States)

    Behrens, Arno; Staneva, Joanna

    2017-04-01

    The Black Sea is with regard to the availability of traditional in situ wave measurements recorded by usual waverider buoys a data sparse semi-enclosed sea. The only possibility for systematic validations of wave model results in such a regional area is the use of satellite data. In the frame of the COPERNICUS Marine Evolution System for the Black Sea that requires wave predictions, the third-generation spectral wave model WAM is used. The operational system is demonstrated based on four years' systematic comparisons with satellite data. The aim of this investigation was to answer two questions. Is the wave model able to provide a reliable description of the wave conditions in the Black Sea and are the satellite measurements suitable for validation purposes on such a regional scale ? Detailed comparisons between measured data and computed model results for the Black Sea including yearly statistics have been done for about 300 satellite overflights per year. The results discussed the different verification schemes needed to review the forecasting skills of the operational system. The good agreement between measured and modeled data supports the expectation that the wave model provides reasonable results and that the satellite data is of good quality and offer an appropriate validation alternative to buoy measurements. This is the required step towards further use of those satellite data for assimilation into the wave fields to improve the wave predictions. Additional support for the good quality of the wave predictions is provided by comparisons between ADCP measurements that are available for a short time period in February 2012 and the corresponding model results at a location near the Bulgarian coast in the western Black Sea. Sensitivity tests with different wave model options and different driving wind fields have been done which identify the appropriate model configuration that provides the best wave predictions. In addition to the comparisons between measured

  20. Transition between process models (BPMN and service models (WS-BPEL and other standards: A systematic review

    Directory of Open Access Journals (Sweden)

    Marko Jurišić

    2011-12-01

    Full Text Available BPMN and BPEL have become de facto standards for modeling of business processes and imple-mentation of business processes via Web services. There is a quintessential problem of discrep-ancy between these two approaches as they are applied in different phases of lifecycle and theirfundamental concepts are different — BPMN is a graph based language while BPEL is basicallya block-based programming language. This paper shows basic concepts and gives an overviewof research and ideas which emerged during last two years, presents state of the art and possiblefuture research directions. Systematic literature review was performed and critical review wasgiven regarding the potential of the given solutions.

  1. What Makes Hydrologic Models Differ? Using SUMMA to Systematically Explore Model Uncertainty and Error

    Science.gov (United States)

    Bennett, A.; Nijssen, B.; Chegwidden, O.; Wood, A.; Clark, M. P.

    2017-12-01

    Model intercomparison experiments have been conducted to quantify the variability introduced during the model development process, but have had limited success in identifying the sources of this model variability. The Structure for Unifying Multiple Modeling Alternatives (SUMMA) has been developed as a framework which defines a general set of conservation equations for mass and energy as well as a common core of numerical solvers along with the ability to set options for choosing between different spatial discretizations and flux parameterizations. SUMMA can be thought of as a framework for implementing meta-models which allows for the investigation of the impacts of decisions made during the model development process. Through this flexibility we develop a hierarchy of definitions which allows for models to be compared to one another. This vocabulary allows us to define the notion of weak equivalence between model instantiations. Through this weak equivalence we develop the concept of model mimicry, which can be used to investigate the introduction of uncertainty and error during the modeling process as well as provide a framework for identifying modeling decisions which may complement or negate one another. We instantiate SUMMA instances that mimic the behaviors of the Variable Infiltration Capacity (VIC) model and the Precipitation Runoff Modeling System (PRMS) by choosing modeling decisions which are implemented in each model. We compare runs from these models and their corresponding mimics across the Columbia River Basin located in the Pacific Northwest of the United States and Canada. From these comparisons, we are able to determine the extent to which model implementation has an effect on the results, as well as determine the changes in sensitivity of parameters due to these implementation differences. By examining these changes in results and sensitivities we can attempt to postulate changes in the modeling decisions which may provide better estimation of

  2. Health literacy and public health: A systematic review and integration of definitions and models

    Science.gov (United States)

    2012-01-01

    Background Health literacy concerns the knowledge and competences of persons to meet the complex demands of health in modern society. Although its importance is increasingly recognised, there is no consensus about the definition of health literacy or about its conceptual dimensions, which limits the possibilities for measurement and comparison. The aim of the study is to review definitions and models on health literacy to develop an integrated definition and conceptual model capturing the most comprehensive evidence-based dimensions of health literacy. Methods A systematic literature review was performed to identify definitions and conceptual frameworks of health literacy. A content analysis of the definitions and conceptual frameworks was carried out to identify the central dimensions of health literacy and develop an integrated model. Results The review resulted in 17 definitions of health literacy and 12 conceptual models. Based on the content analysis, an integrative conceptual model was developed containing 12 dimensions referring to the knowledge, motivation and competencies of accessing, understanding, appraising and applying health-related information within the healthcare, disease prevention and health promotion setting, respectively. Conclusions Based upon this review, a model is proposed integrating medical and public health views of health literacy. The model can serve as a basis for developing health literacy enhancing interventions and provide a conceptual basis for the development and validation of measurement tools, capturing the different dimensions of health literacy within the healthcare, disease prevention and health promotion settings. PMID:22276600

  3. Health literacy and public health: A systematic review and integration of definitions and models

    LENUS (Irish Health Repository)

    Sorensen, Kristine

    2012-01-25

    Abstract Background Health literacy concerns the knowledge and competences of persons to meet the complex demands of health in modern society. Although its importance is increasingly recognised, there is no consensus about the definition of health literacy or about its conceptual dimensions, which limits the possibilities for measurement and comparison. The aim of the study is to review definitions and models on health literacy to develop an integrated definition and conceptual model capturing the most comprehensive evidence-based dimensions of health literacy. Methods A systematic literature review was performed to identify definitions and conceptual frameworks of health literacy. A content analysis of the definitions and conceptual frameworks was carried out to identify the central dimensions of health literacy and develop an integrated model. Results The review resulted in 17 definitions of health literacy and 12 conceptual models. Based on the content analysis, an integrative conceptual model was developed containing 12 dimensions referring to the knowledge, motivation and competencies of accessing, understanding, appraising and applying health-related information within the healthcare, disease prevention and health promotion setting, respectively. Conclusions Based upon this review, a model is proposed integrating medical and public health views of health literacy. The model can serve as a basis for developing health literacy enhancing interventions and provide a conceptual basis for the development and validation of measurement tools, capturing the different dimensions of health literacy within the healthcare, disease prevention and health promotion settings.

  4. A critical comparison of systematic calibration protocols for activated sludge models: a SWOT analysis.

    Science.gov (United States)

    Sin, Gürkan; Van Hulle, Stijn W H; De Pauw, Dirk J W; van Griensven, Ann; Vanrolleghem, Peter A

    2005-07-01

    Modelling activated sludge systems has gained an increasing momentum after the introduction of activated sludge models (ASMs) in 1987. Application of dynamic models for full-scale systems requires essentially a calibration of the chosen ASM to the case under study. Numerous full-scale model applications have been performed so far which were mostly based on ad hoc approaches and expert knowledge. Further, each modelling study has followed a different calibration approach: e.g. different influent wastewater characterization methods, different kinetic parameter estimation methods, different selection of parameters to be calibrated, different priorities within the calibration steps, etc. In short, there was no standard approach in performing the calibration study, which makes it difficult, if not impossible, to (1) compare different calibrations of ASMs with each other and (2) perform internal quality checks for each calibration study. To address these concerns, systematic calibration protocols have recently been proposed to bring guidance to the modeling of activated sludge systems and in particular to the calibration of full-scale models. In this contribution four existing calibration approaches (BIOMATH, HSG, STOWA and WERF) will be critically discussed using a SWOT (Strengths, Weaknesses, Opportunities, Threats) analysis. It will also be assessed in what way these approaches can be further developed in view of further improving the quality of ASM calibration. In this respect, the potential of automating some steps of the calibration procedure by use of mathematical algorithms is highlighted.

  5. A systematic procedure for the incorporation of common cause events into risk and reliability models

    International Nuclear Information System (INIS)

    Fleming, K.N.; Mosleh, A.; Deremer, R.K.

    1986-01-01

    Common cause events are an important class of dependent events with respect to their contribution to system unavailability and to plant risk. Unfortunately, these events have not been treated with any king of consistency in applied risk studies over the past decade. Many probabilistic risk assessments (PRA) have not included these events at all, and those that have did not employ the kind of systematic procedures that are needed to achieve consistency, accuracy, and credibility in this area of PRA methodology. In this paper, the authors report on the progress recently made in the development of a systematic approach for incorporating common cause events into applied risk and reliability evaluations. This approach takes advantage of experience from recently completed PRAs and is the result of a project, sponsored by the Electric Power Research Institute (EPRI), in which procedures for dependent events analysis are being developed. Described in this paper is a general framework for system-level common cause failure (CCF) analysis and its application to a three-train auxiliary feedwater system. Within this general framework, three parametric CCF models are compared, including the basic parameter (BP), multiple Greek letter (MGL), and binominal failure rate (BFR) models. Pitfalls of not following the recommended procedure are discussed, and some old issues, such as the benefits of redundancy and diversity, are reexamined. (orig.)

  6. Mathematical Models in Humanitarian Supply Chain Management: A Systematic Literature Review

    Directory of Open Access Journals (Sweden)

    Muhammad Salman Habib

    2016-01-01

    Full Text Available In the past decade the humanitarian supply chain (HSC has attracted the attention of researchers due to the increasing frequency of disasters. The uncertainty in time, location, and severity of disaster during predisaster phase and poor conditions of available infrastructure during postdisaster phase make HSC operations difficult to handle. In order to overcome the difficulties during these phases, we need to assure that HSC operations are designed in an efficient manner to minimize human and economic losses. In the recent times, several mathematical optimization techniques and algorithms have been developed to increase the efficiency of HSC operations. These techniques and algorithms developed for the field of HSC motivate the need of a systematic literature review. Owing to the importance of mathematical modelling techniques, this paper presents the review of the mathematical contributions made in the last decade in the field of HSC. A systematic literature review methodology is used for this paper due to its transparent procedure. There are two objectives of this study: the first one is to conduct an up-to-date survey of mathematical models developed in HSC area and the second one is to highlight the potential research areas which require attention of the researchers.

  7. A comprehensive model for executing knowledge management audits in organizations: a systematic review.

    Science.gov (United States)

    Shahmoradi, Leila; Ahmadi, Maryam; Sadoughi, Farahnaz; Piri, Zakieh; Gohari, Mahmood Reza

    2015-01-01

    A knowledge management audit (KMA) is the first phase in knowledge management implementation. Incomplete or incomprehensive execution of the KMA has caused many knowledge management programs to fail. A study was undertaken to investigate how KMAs are performed systematically in organizations and present a comprehensive model for performing KMAs based on a systematic review. Studies were identified by searching electronic databases such as Emerald, LISA, and the Cochrane library and e-journals such as the Oxford Journal and hand searching of printed journals, theses, and books in the Tehran University of Medical Sciences digital library. The sources used in this study consisted of studies available through the digital library of the Tehran University of Medical Sciences that were published between 2000 and 2013, including both Persian- and English-language sources, as well as articles explaining the steps involved in performing a KMA. A comprehensive model for KMAs is presented in this study. To successfully execute a KMA, it is necessary to perform the appropriate preliminary activities in relation to the knowledge management infrastructure, determine the knowledge management situation, and analyze and use the available data on this situation.

  8. The Perception of Time Is Underestimated in Adolescents With Anorexia Nervosa

    Directory of Open Access Journals (Sweden)

    Carmelo M. Vicario

    2018-04-01

    Full Text Available Research has revealed reduced temporal discounting (i.e., increased capacity to delay reward and altered interoceptive awareness in anorexia nervosa (AN. In line with the research linking temporal underestimation with a reduced tendency to devalue a reward and reduced interoceptive awareness, we tested the hypothesis that time duration might be underestimated in AN. Our findings revealed that patients with AN displayed lower timing accuracy in the form of timing underestimation compared with controls. These results were not predicted by clinical, demographic factors, attention, and working memory performance of the participants. The evidence of a temporal underestimation bias in AN might be clinically relevant to explain their abnormal motivation in pursuing a long-term restrictive diet, in line with the evidence that increasing the subjective temporal proximity of remote future goals can boost motivation and the actual behavior to reach them.

  9. Stress Underestimation and Mental Health Outcomes in Male Japanese Workers: a 1-Year Prospective Study.

    Science.gov (United States)

    Izawa, Shuhei; Nakamura-Taira, Nanako; Yamada, Kosuke Chris

    2016-12-01

    Being appropriately aware of the extent of stress experienced in daily life is essential in motivating stress management behaviours. Excessive stress underestimation obstructs this process, which is expected to exert adverse effects on health. We prospectively examined associations between stress underestimation and mental health outcomes in Japanese workers. Web-based surveys were conducted twice with an interval of 1 year on 2359 Japanese male workers. Participants were asked to complete survey items concerning stress underestimation, depressive symptoms, sickness absence, and antidepressant use. Multiple logistic regression analysis revealed that high baseline levels of 'overgeneralization of stress' and 'insensitivity to stress' were significantly associated with new-onset depressive symptoms (OR = 2.66 [95 % CI, 1.54-4.59], p stress underestimation, including stress insensitivity and the overgeneralization of stress, could exert adverse effects on mental health.

  10. Influenza pneumonia surveillance among hospitalized adults may underestimate the burden of severe influenza disease.

    Directory of Open Access Journals (Sweden)

    Justin R Ortiz

    Full Text Available Studies seeking to estimate the burden of influenza among hospitalized adults often use case definitions that require presence of pneumonia. The goal of this study was to assess the extent to which restricting influenza testing to adults hospitalized with pneumonia could underestimate the total burden of hospitalized influenza disease.We conducted a modelling study using the complete State Inpatient Databases from Arizona, California, and Washington and regional influenza surveillance data acquired from CDC from January 2003 through March 2009. The exposures of interest were positive laboratory tests for influenza A (H1N1, influenza A (H3N2, and influenza B from two contiguous US Federal Regions encompassing the study area. We identified the two outcomes of interest by ICD-9-CM code: respiratory and circulatory hospitalizations, as well as critical illness hospitalizations (acute respiratory failure, severe sepsis, and in-hospital death. We linked the hospitalization datasets with the virus surveillance datasets by geographic region and month of hospitalization. We used negative binomial regression models to estimate the number of influenza-associated events for the outcomes of interest. We sub-categorized these events to include all outcomes with or without pneumonia diagnosis codes.We estimated that there were 80,834 (95% CI 29,214-174,033 influenza-associated respiratory and circulatory hospitalizations and 26,760 (95% CI 14,541-47,464 influenza-associated critical illness hospitalizations. When a pneumonia diagnosis was excluded, the estimated number of influenza-associated respiratory and circulatory hospitalizations was 24,816 (95% CI 6,342-92,624. The estimated number of influenza-associated critical illness hospitalizations was 8,213 (95% CI 3,764-20,799. Around 30% of both influenza-associated respiratory and circulatory hospitalizations, as well as influenza-associated critical illness hospitalizations did not have pneumonia diagnosis

  11. Systematics of nuclear densities, deformations and excitation energies within the context of the generalized rotation-vibration model

    Energy Technology Data Exchange (ETDEWEB)

    Chamon, L.C., E-mail: luiz.chamon@dfn.if.usp.b [Departamento de Fisica Nuclear, Instituto de Fisica da Universidade de Sao Paulo, Caixa Postal 66318, 05315-970, Sao Paulo, SP (Brazil); Carlson, B.V. [Departamento de Fisica, Instituto Tecnologico de Aeronautica, Centro Tecnico Aeroespacial, Sao Jose dos Campos, SP (Brazil)

    2010-11-30

    We present a large-scale systematics of charge densities, excitation energies and deformation parameters for hundreds of heavy nuclei. The systematics is based on a generalized rotation-vibration model for the quadrupole and octupole modes and takes into account second-order contributions of the deformations as well as the effects of finite diffuseness values for the nuclear densities. We compare our results with the predictions of classical surface vibrations in the hydrodynamical approximation.

  12. Boulder-based wave hindcasting underestimates storm size

    Science.gov (United States)

    Kennedy, David; Woods, Joesphine; Rosser, Nick; Hansom, James; Naylor, Larissa

    2017-04-01

    Large boulder-size clasts represent an important archive of erosion and wave activity on the coast. From tropical coral reefs to eroding cliffs in the high-latitudes, boulders have been used to hindcast the frequency and magnitude of cyclones and tsunami. Such reconstructions are based on the balance between the hydrodynamic forces acting on individual clasts and the counteracting resistive forces of friction and gravity. Here we test the three principle hindcasting relationships on nearly 1000 intertidal boulders in North Yorkshire, U.K using a combination of field and airborne terrestrial LiDAR data. We quantify the predicted versus actual rates of movement and the degree to which local geomorphology can retard or accelerate transport. Actual clast movement is significantly less than predicted values, regardless of boulder volume, shape or location. In situ cementation of clasts to the substrate by marine organisms and clustering of clasts increases friction thereby preventing transport. The implication is that boulders do not always provide a reliable estimation of wave height on the coast and reliance solely on hindcasting relationships leads to an under prediction of the frequency and magnitude of past storm wave activity. The crucial need for process field studies to refine boulder transport models is thus demonstrated.

  13. Selective IgM Deficiency—An Underestimated Primary Immunodeficiency

    Directory of Open Access Journals (Sweden)

    Sudhir Gupta

    2017-09-01

    Full Text Available Although selective IgM deficiency (SIGMD was described almost five decades ago, it was largely ignored as a primary immunodeficiency. SIGMD is defined as serum IgM levels below two SD of mean with normal serum IgG and IgA. It appears to be more common than originally realized. SIGMD is observed in both children and adults. Patients with SIGMD may be asymptomatic; however, approximately 80% of patients with SIGMD present with infections with bacteria, viruses, fungi, and protozoa. There is an increased frequency of allergic and autoimmune diseases in SIGMD. A number of B cell subset abnormalities have been reported and impaired specific antibodies to Streptococcus pneumoniae responses are observed in more than 45% of cases. Innate immunity, T cells, T cell subsets, and T cell functions are essentially normal. The pathogenesis of SIGMD remains unclear. Mice selectively deficient in secreted IgM are also unable to control infections from bacterial, viral, and fungal pathogens, and develop autoimmunity. Immunological and clinical similarities and differences between mouse models of deficiency of secreted IgM and humans with SIGMD have been discussed. Patients with SIGMD presenting with recurrent infections and specific antibody deficiency responses appear to improve clinically on immunoglobulin therapy.

  14. Effects of Photobiomodulation Therapy on Oxidative Stress in Muscle Injury Animal Models: A Systematic Review.

    Science.gov (United States)

    Dos Santos, Solange Almeida; Serra, Andrey Jorge; Stancker, Tatiane Garcia; Simões, Maíra Cecília Brandão; Dos Santos Vieira, Marcia Ataíze; Leal-Junior, Ernesto Cesar; Prokic, Marko; Vasconsuelo, Andrea; Santos, Simone Silva; de Carvalho, Paulo de Tarso Camillo

    2017-01-01

    This systematic review was performed to identify the role of photobiomodulation therapy on experimental muscle injury models linked to induce oxidative stress. EMBASE, PubMed, and CINAHL were searched for studies published from January 2006 to January 2016 in the areas of laser and oxidative stress. Any animal model using photobiomodulation therapy to modulate oxidative stress was included in analysis. Eight studies were selected from 68 original articles targeted on laser irradiation and oxidative stress. Articles were critically assessed by two independent raters with a structured tool for rating the research quality. Although the small number of studies limits conclusions, the current literature indicates that photobiomodulation therapy can be an effective short-term approach to reduce oxidative stress markers (e.g., thiobarbituric acid-reactive) and to increase antioxidant substances (e.g., catalase, glutathione peroxidase, and superoxide dismutase). However, there is a nonuniformity in the terminology used to describe the parameters and dose for low-level laser treatment.

  15. Religion and Spirituality's Influences on HIV Syndemics Among MSM: A Systematic Review and Conceptual Model.

    Science.gov (United States)

    Lassiter, Jonathan M; Parsons, Jeffrey T

    2016-02-01

    This paper presents a systematic review of the quantitative HIV research that assessed the relationships between religion, spirituality, HIV syndemics, and individual HIV syndemics-related health conditions (e.g. depression, substance abuse, HIV risk) among men who have sex with men (MSM) in the United States. No quantitative studies were found that assessed the relationships between HIV syndemics, religion, and spirituality. Nine studies, with 13 statistical analyses, were found that examined the relationships between individual HIV syndemics-related health conditions, religion, and spirituality. Among the 13 analyses, religion and spirituality were found to have mixed relationships with HIV syndemics-related health conditions (6 nonsignificant associations; 5 negative associations; 2 positive associations). Given the overall lack of inclusion of religion and spirituality in HIV syndemics research, a conceptual model that hypothesizes the potential interactions of religion and spirituality with HIV syndemics-related health conditions is presented. The implications of the model for MSM's health are outlined.

  16. Stress underestimation and mental health literacy of depression in Japanese workers: A cross-sectional study.

    Science.gov (United States)

    Nakamura-Taira, Nanako; Izawa, Shuhei; Yamada, Kosuke Chris

    2018-04-01

    Appropriately estimating stress levels in daily life is important for motivating people to undertake stress-management behaviors or seek out information on stress management and mental health. People who exhibit high stress underestimation might not be interested in information on mental health, and would therefore have less knowledge of it. We investigated the association between stress underestimation tendency and mental health literacy of depression (i.e., knowledge of the recognition, prognosis, and usefulness of resources of depression) in Japanese workers. We cross-sectionally surveyed 3718 Japanese workers using a web-based questionnaire on stress underestimation, mental health literacy of depression (vignettes on people with depression), and covariates (age, education, depressive symptoms, income, and worksite size). After adjusting for covariates, high stress underestimation was associated with greater odds of not recognizing depression (i.e., choosing anything other than depression). Furthermore, these individuals had greater odds of expecting the case to improve without treatment and not selecting useful sources of support (e.g. talk over with friends/family, see a psychiatrist, take medication, see a counselor) compared to those with moderate stress underestimation. These relationships were all stronger among males than among females. Stress underestimation was related to poorer mental health literacy of depression. Copyright © 2018 Elsevier B.V. All rights reserved.

  17. A systematic review of predictive models for asthma development in children.

    Science.gov (United States)

    Luo, Gang; Nkoy, Flory L; Stone, Bryan L; Schmick, Darell; Johnson, Michael D

    2015-11-28

    Asthma is the most common pediatric chronic disease affecting 9.6 % of American children. Delay in asthma diagnosis is prevalent, resulting in suboptimal asthma management. To help avoid delay in asthma diagnosis and advance asthma prevention research, researchers have proposed various models to predict asthma development in children. This paper reviews these models. A systematic review was conducted through searching in PubMed, EMBASE, CINAHL, Scopus, the Cochrane Library, the ACM Digital Library, IEEE Xplore, and OpenGrey up to June 3, 2015. The literature on predictive models for asthma development in children was retrieved, with search results limited to human subjects and children (birth to 18 years). Two independent reviewers screened the literature, performed data extraction, and assessed article quality. The literature search returned 13,101 references in total. After manual review, 32 of these references were determined to be relevant and are discussed in the paper. We identify several limitations of existing predictive models for asthma development in children, and provide preliminary thoughts on how to address these limitations. Existing predictive models for asthma development in children have inadequate accuracy. Efforts to improve these models' performance are needed, but are limited by a lack of a gold standard for asthma development in children.

  18. Behavioural change models for infectious disease transmission: a systematic review (2010–2015)

    Science.gov (United States)

    2016-01-01

    We review behavioural change models (BCMs) for infectious disease transmission in humans. Following the Cochrane collaboration guidelines and the PRISMA statement, our systematic search and selection yielded 178 papers covering the period 2010–2015. We observe an increasing trend in published BCMs, frequently coupled to (re)emergence events, and propose a categorization by distinguishing how information translates into preventive actions. Behaviour is usually captured by introducing information as a dynamic parameter (76/178) or by introducing an economic objective function, either with (26/178) or without (37/178) imitation. Approaches using information thresholds (29/178) and exogenous behaviour formation (16/178) are also popular. We further classify according to disease, prevention measure, transmission model (with 81/178 population, 6/178 metapopulation and 91/178 individual-level models) and the way prevention impacts transmission. We highlight the minority (15%) of studies that use any real-life data for parametrization or validation and note that BCMs increasingly use social media data and generally incorporate multiple sources of information (16/178), multiple types of information (17/178) or both (9/178). We conclude that individual-level models are increasingly used and useful to model behaviour changes. Despite recent advancements, we remain concerned that most models are purely theoretical and lack representative data and a validation process. PMID:28003528

  19. Computer simulation models of pre-diabetes populations: a systematic review protocol.

    Science.gov (United States)

    Leal, Jose; Khurshid, Waqar; Pagano, Eva; Feenstra, Talitha

    2017-10-05

    Diabetes is a major public health problem and prediabetes (intermediate hyperglycaemia) is associated with a high risk of developing diabetes. With evidence supporting the use of preventive interventions for prediabetes populations and the discovery of novel biomarkers stratifying the risk of progression, there is a need to evaluate their cost-effectiveness across jurisdictions. In diabetes and prediabetes, it is relevant to inform cost-effectiveness analysis using decision models due to their ability to forecast long-term health outcomes and costs beyond the time frame of clinical trials. To support good implementation and reimbursement decisions of interventions in these populations, models should be clinically credible, based on best available evidence, reproducible and validated against clinical data. Our aim is to identify recent studies on computer simulation models and model-based economic evaluations of populations of individuals with prediabetes, qualify them and discuss the knowledge gaps, challenges and opportunities that need to be addressed for future evaluations. A systematic review will be conducted in MEDLINE, Embase, EconLit and National Health Service Economic Evaluation Database. We will extract peer-reviewed studies published between 2000 and 2016 that describe computer simulation models of the natural history of individuals with prediabetes and/or decision models to evaluate the impact of interventions, risk stratification and/or screening on these populations. Two reviewers will independently assess each study for inclusion. Data will be extracted using a predefined pro forma developed using best practice. Study quality will be assessed using a modelling checklist. A narrative synthesis of all studies will be presented, focussing on model structure, quality of models and input data, and validation status. This systematic review is exempt from ethics approval because the work is carried out on published documents. The findings of the review

  20. Theories, models and frameworks used in capacity building interventions relevant to public health: a systematic review.

    Science.gov (United States)

    Bergeron, Kim; Abdi, Samiya; DeCorby, Kara; Mensah, Gloria; Rempel, Benjamin; Manson, Heather

    2017-11-28

    There is limited research on capacity building interventions that include theoretical foundations. The purpose of this systematic review is to identify underlying theories, models and frameworks used to support capacity building interventions relevant to public health practice. The aim is to inform and improve capacity building practices and services offered by public health organizations. Four search strategies were used: 1) electronic database searching; 2) reference lists of included papers; 3) key informant consultation; and 4) grey literature searching. Inclusion and exclusion criteria are outlined with included papers focusing on capacity building, learning plans, professional development plans in combination with tools, resources, processes, procedures, steps, model, framework, guideline, described in a public health or healthcare setting, or non-government, government, or community organizations as they relate to healthcare, and explicitly or implicitly mention a theory, model and/or framework that grounds the type of capacity building approach developed. Quality assessment were performed on all included articles. Data analysis included a process for synthesizing, analyzing and presenting descriptive summaries, categorizing theoretical foundations according to which theory, model and/or framework was used and whether or not the theory, model or framework was implied or explicitly identified. Nineteen articles were included in this review. A total of 28 theories, models and frameworks were identified. Of this number, two theories (Diffusion of Innovations and Transformational Learning), two models (Ecological and Interactive Systems Framework for Dissemination and Implementation) and one framework (Bloom's Taxonomy of Learning) were identified as the most frequently cited. This review identifies specific theories, models and frameworks to support capacity building interventions relevant to public health organizations. It provides public health practitioners

  1. Endogenous opioid antagonism in physiological experimental pain models: a systematic review.

    Directory of Open Access Journals (Sweden)

    Mads U Werner

    Full Text Available Opioid antagonists are pharmacological tools applied as an indirect measure to detect activation of the endogenous opioid system (EOS in experimental pain models. The objective of this systematic review was to examine the effect of mu-opioid-receptor (MOR antagonists in placebo-controlled, double-blind studies using 'inhibitory' or 'sensitizing', physiological test paradigms in healthy human subjects. The databases PubMed and Embase were searched according to predefined criteria. Out of a total of 2,142 records, 63 studies (1,477 subjects [male/female ratio = 1.5] were considered relevant. Twenty-five studies utilized 'inhibitory' test paradigms (ITP and 38 studies utilized 'sensitizing' test paradigms (STP. The ITP-studies were characterized as conditioning modulation models (22 studies and repetitive transcranial magnetic stimulation models (rTMS; 3 studies, and, the STP-studies as secondary hyperalgesia models (6 studies, 'pain' models (25 studies, summation models (2 studies, nociceptive reflex models (3 studies and miscellaneous models (2 studies. A consistent reversal of analgesia by a MOR-antagonist was demonstrated in 10 of the 25 ITP-studies, including stress-induced analgesia and rTMS. In the remaining 14 conditioning modulation studies either absence of effects or ambiguous effects by MOR-antagonists, were observed. In the STP-studies, no effect of the opioid-blockade could be demonstrated in 5 out of 6 secondary hyperalgesia studies. The direction of MOR-antagonist dependent effects upon pain ratings, threshold assessments and somatosensory evoked potentials (SSEP, did not appear consistent in 28 out of 32 'pain' model studies. In conclusion, only in 2 experimental human pain models, i.e., stress-induced analgesia and rTMS, administration of MOR-antagonist demonstrated a consistent effect, presumably mediated by an EOS-dependent mechanisms of analgesia and hyperalgesia.

  2. External validation of multivariable prediction models: a systematic review of methodological conduct and reporting

    Science.gov (United States)

    2014-01-01

    Background Before considering whether to use a multivariable (diagnostic or prognostic) prediction model, it is essential that its performance be evaluated in data that were not used to develop the model (referred to as external validation). We critically appraised the methodological conduct and reporting of external validation studies of multivariable prediction models. Methods We conducted a systematic review of articles describing some form of external validation of one or more multivariable prediction models indexed in PubMed core clinical journals published in 2010. Study data were extracted in duplicate on design, sample size, handling of missing data, reference to the original study developing the prediction models and predictive performance measures. Results 11,826 articles were identified and 78 were included for full review, which described the evaluation of 120 prediction models. in participant data that were not used to develop the model. Thirty-three articles described both the development of a prediction model and an evaluation of its performance on a separate dataset, and 45 articles described only the evaluation of an existing published prediction model on another dataset. Fifty-seven percent of the prediction models were presented and evaluated as simplified scoring systems. Sixteen percent of articles failed to report the number of outcome events in the validation datasets. Fifty-four percent of studies made no explicit mention of missing data. Sixty-seven percent did not report evaluating model calibration whilst most studies evaluated model discrimination. It was often unclear whether the reported performance measures were for the full regression model or for the simplified models. Conclusions The vast majority of studies describing some form of external validation of a multivariable prediction model were poorly reported with key details frequently not presented. The validation studies were characterised by poor design, inappropriate handling

  3. Self-reported versus measured body height and weight in Polish adult men: the risk of underestimating obesity rates.

    Science.gov (United States)

    Łopuszańska, Monika; Lipowicz, Anna; Kołodziej, Halina; Szklarska, Alicja; Bielicki, Tadeusz

    2015-01-01

    In some epidemiological studies, self-reported height and weight are often used to save time and money. Self-reported height and weight are commonly used to assess the prevalence of obesity. The aim of this study was to assess the differences between self-reported and measured height and weight in adult men, and to determine how the accuracy of self-reported data depended on age and education. The prevalence of obesity was also calculated based both on self-reported and measured data. Data were collected during two population studies carried out in Wroclaw in 2010. One study included 1,194 19-year-old males who reported for the health examination mandated by the National Conscription Board (younger group). The other group included 355 men between 35 and 80 years old who reported for a ten-year follow-up (older group). Data were analyzed separately for both age groups. Both younger and older subjects overestimated their height by 1.4 cm and 1.0 cm (1.4 cm, 95 % CI: 1.26, 1.51, and 1.0 cm, 95 % CI: 0.85, 1.26, respectively). On average, younger subjects overestimated their weight by 0.7 kilograms (95 % CI: 0.55, 0.92), whereas older subjects underestimated their weight by 0.9 kilograms (95 % CI: -1.15, -0.48). The lower the level of education, the more the subjects overestimated their height. Adult men systematically overestimate their height and underestimate their weight. The magnitude of the inaccuracy depends on level of education. When self-reported data are used, the prevalence of obesity is generally underestimated. Using self-reported data to calculate BMI can lead to a substantial underestimation of the proportion of underweight and obese individuals in a population. Finally, using self-reported values for height in studies on social inequality may lead to false conclusions. Background: In some epidemiological studies, self-reported height and weight are often used to save time and money. Self-reported height and weight are commonly used to assess the

  4. Systematizing Web Search through a Meta-Cognitive, Systems-Based, Information Structuring Model (McSIS)

    Science.gov (United States)

    Abuhamdieh, Ayman H.; Harder, Joseph T.

    2015-01-01

    This paper proposes a meta-cognitive, systems-based, information structuring model (McSIS) to systematize online information search behavior based on literature review of information-seeking models. The General Systems Theory's (GST) prepositions serve as its framework. Factors influencing information-seekers, such as the individual learning…

  5. A systematic study of multiple minerals precipitation modelling in wastewater treatment.

    Science.gov (United States)

    Kazadi Mbamba, Christian; Tait, Stephan; Flores-Alsina, Xavier; Batstone, Damien J

    2015-11-15

    Mineral solids precipitation is important in wastewater treatment. However approaches to minerals precipitation modelling are varied, often empirical, and mostly focused on single precipitate classes. A common approach, applicable to multi-species precipitates, is needed to integrate into existing wastewater treatment models. The present study systematically tested a semi-mechanistic modelling approach, using various experimental platforms with multiple minerals precipitation. Experiments included dynamic titration with addition of sodium hydroxide to synthetic wastewater, and aeration to progressively increase pH and induce precipitation in real piggery digestate and sewage sludge digestate. The model approach consisted of an equilibrium part for aqueous phase reactions and a kinetic part for minerals precipitation. The model was fitted to dissolved calcium, magnesium, total inorganic carbon and phosphate. Results indicated that precipitation was dominated by the mineral struvite, forming together with varied and minor amounts of calcium phosphate and calcium carbonate. The model approach was noted to have the advantage of requiring a minimal number of fitted parameters, so the model was readily identifiable. Kinetic rate coefficients, which were statistically fitted, were generally in the range 0.35-11.6 h(-1) with confidence intervals of 10-80% relative. Confidence regions for the kinetic rate coefficients were often asymmetric with model-data residuals increasing more gradually with larger coefficient values. This suggests that a large kinetic coefficient could be used when actual measured data is lacking for a particular precipitate-matrix combination. Correlation between the kinetic rate coefficients of different minerals was low, indicating that parameter values for individual minerals could be independently fitted (keeping all other model parameters constant). Implementation was therefore relatively flexible, and would be readily expandable to include other

  6. SModelS: A Tool for Making Systematic Use of Simplified Models Results

    Science.gov (United States)

    Waltenberger, Wolfgang; SModelS Group

    2016-10-01

    We present an automated software tool ”SModelS” to systematically confront theories Beyond the Standard Model (BSM) with experimental data. The tool consists of a general procedure to decompose such BSM theories into their Simplified Models Spectra (SMS). In addition, SModelS features a database containing the majority of the published SMS results of CMS and ATLAS. These results consist of the 95% confidence level upper limits on signal production cross sections. The two components together allow us to quickly confront any BSM model with LHC results. As a show-case example we will briefly discuss an application of our procedure to a specific supersymmetric model. It is one of our ongoing efforts to extend the framework to include also efficiency maps produced either by the experimental collaborations, by efforts performed within the phenomenological groups, or possibly also by ourselves. While the current implementation can handle null results only, it is our ultimate goal to build the Next Standard Model in a bottom-up fashion from both negative and positive results of several experiments. The implementation is open source, written in python, and available from http://smodels.hephy.at.

  7. Anxiety in the context of cancer: A systematic review and development of an integrated model.

    Science.gov (United States)

    Curran, Leah; Sharpe, Louise; Butow, Phyllis

    2017-08-01

    Anxiety is common in the context of cancer, but there are few theoretical models that apply to people with cancer across the trajectory of their illness. The aims of this review are to identify existing theories and to propose an integrated model of cancer-related anxiety. Using a systematic literature search of Medline, Premedline and PsycINFO databases, we identified nine theoretical models of anxiety in the context of cancer. We reviewed these for psychological concepts that fell under five themes: pre-existing schema, the inherent nature of cancer, cognitive factors, coping responses and contextual factors. From these themes, we integrated concepts from different models to develop a theoretical framework to explain the development and maintenance of anxiety in the context of cancer. The resulting model suggests that pre-existing schema, past experiences of cancer, an intolerance of uncertainty and meta-cognitive beliefs about worry interact with the inherent nature of cancer to produce overwhelming distress. The distress activates cognitive processes characterized by vigilance, worry and rumination. Attempts to cope by re-establishing control, and a pattern of vigilance to cancer-related cues and/or avoidance reinforce anxiety, in the context of a range of systemic factors that can either buffer against or worsen the anxiety. Copyright © 2017. Published by Elsevier Ltd.

  8. An extended systematic mapping study about the scalability of i* Models

    Directory of Open Access Journals (Sweden)

    Paulo Lima

    2016-12-01

    Full Text Available i* models have been used for requirements specification in many domains, such as healthcare, telecommunication, and air traffic control. Managing the scalability and the complexity of such models is an important challenge in Requirements Engineering (RE. Scalability is also one of the most intractable issues in the design of visual notations in general: a well-known problem with visual representations is that they do not scale well. This issue has led us to investigate scalability in i* models and its variants by means of a systematic mapping study. This paper is an extended version of a previous paper on the scalability of i* including papers indicated by specialists. Moreover, we also discuss the challenges and open issues regarding scalability of i* models and its variants. A total of 126 papers were analyzed in order to understand: how the RE community perceives scalability; and which proposals have considered this topic. We found that scalability issues are indeed perceived as relevant and that further work is still required, even though many potential solutions have already been proposed. This study can be a starting point for researchers aiming to further advance the treatment of scalability in i* models.

  9. [Skilled communication as "intervention" : Models for systematic communication in the healthcare system].

    Science.gov (United States)

    Weinert, M; Mayer, H; Zojer, E

    2015-02-01

    Specific communication training is currently not integrated into anesthesiology curricula. At the same time communication is an important key factor when working with colleagues, in the physician-patient relationship, during management of emergencies and in avoiding or reducing the legal consequences of adverse medical events. Therefore, focused attention should be brought to this area. In other high risk industries, specific communication training has been standard for a long time and in medicine there is an approach to teach and train these soft skills by simulation. Systematic communication training, however, is rarely an established component of specialist training. It is impossible not to communicate whereby nonverbal indications, such as gestures, mimic expression, posture and tone play an important part. Miscommunication, however, is common and leads to unproductive behavior. The cause of this is not always obvious. This article provides an overview of the communication models of Shannon, Watzlawick et al. and Schulz von Thun et al. and describes their limitations. The "Process Communication Model®" (PCM) is also introduced. An overview is provided with examples of how this tool can be used to look at the communication process from a systematic point of view. People have different psychological needs. Not taking care of these needs will result in individual stress behavior, which can be graded into first, second and third degrees of severity (driver behavior, mask behavior and desperation). These behavior patterns become exposed in predictable sequences. Furthermore, on the basis of this model, successful communication can be established while unproductive behavior that occurs during stress can be dealt with appropriately. Because of the importance of communication in all areas of medical care, opportunities exist to focus research on the influence of targeted communication on patient outcome, complications and management of emergencies.

  10. Mesenchymal Stromal Cells in Animal Bleomycin Pulmonary Fibrosis Models: A Systematic Review.

    Science.gov (United States)

    Srour, Nadim; Thébaud, Bernard

    2015-12-01

    Idiopathic pulmonary fibrosis is an inexorably progressive lung disease with few available treatments. New therapeutic options are needed. Stem cells have generated much enthusiasm for the treatment of several conditions, including lung diseases. Human trials of mesenchymal stromal cell (MSC) therapy for pulmonary fibrosis are under way. To shed light on the potential usefulness of MSCs for human disease, we aimed to systematically review the preclinical literature to determine if MSCs are beneficial in animal bleomycin pulmonary fibrosis models. The MEDLINE and Embase databases were searched for original studies of stem cell therapy in animal bleomycin models of pulmonary fibrosis. Studies using embryonic stem cells or induced pluripotent stem cells were excluded. Seventeen studies were selected, all of which used MSCs in rodents. MSC therapy led to an improvement in bleomycin-induced lung collagen deposition in animal lungs and in the pulmonary fibrosis Ashcroft score in most studies. MSC therapy improved histopathology in almost all studies in which it was evaluated qualitatively. Furthermore, MSC therapy was found to improve 14-day survival in animals with bleomycin-induced pulmonary fibrosis. Bronchoalveolar lavage total and neutrophil counts, as well as transforming growth factor-β levels, were also reduced by MSCs. MSCs are beneficial in rodent bleomycin pulmonary fibrosis models. Since most studies examined the initial inflammatory phase rather than the chronic fibrotic phase, preclinical data offer better support for human trials of MSCs in acute exacerbations of pulmonary fibrosis rather than the chronic phase of the disease. There has been increased interest in mesenchymal stromal cell therapy for lung diseases. A few small clinical trials are under way in idiopathic pulmonary fibrosis. Preclinical evidence was assessed in a systematic review, as is often done for clinical studies. The existing studies offer better support for efficacy in the initial

  11. Periodontal ligament-derived cells for periodontal regeneration in animal models: a systematic review.

    Science.gov (United States)

    Bright, R; Hynes, K; Gronthos, S; Bartold, P M

    2015-04-01

    Implantation of periodontal ligament stem cells is emerging as a potential periodontal regenerative procedure. This systematic review considers the evidence from animal models investigating the use of periodontal ligament stem cells for successful periodontal regeneration. PubMed, Embase, MEDLINE and Google Scholar were searched to December 2013 for quantitative studies examining the outcome of implanting periodontal ligament stem cells into experimental periodontal defects in animals. Inclusion criteria were: implantation of periodontal ligament stem cells into surgically created periodontal defects for periodontal regeneration; animal models only; source of cells either human or animal; and published in English. We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. From the literature search, 43 studies met the inclusion criteria. A wide variety of surgical defects were created in four species of animal (dog, rat, pig and sheep). Owing to wide variability in defect type, cell source and cell scaffold, no meta-analysis was possible. Outcome measures included new bone, new cementum and new connective tissue formation. In 70.5% of the results, statistically significant improvements of these measures was recorded. These results are notable in that they indicate that irrespective of the defect type and animal model used, periodontal ligament stem cell implantation can be expected to result in a beneficial outcome for periodontal regeneration. It is recommended that there is sufficient evidence from preclinical animal studies to warrant moving to human studies to examine the efficacy, safety, feasibility (autologous vs. allogeneic transplantation) and delivery of periodontal ligament stem cells for periodontal regeneration. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  12. Policy-Relevant Systematic Reviews to Strengthen Health Systems: Models and Mechanisms to Support Their Production

    Science.gov (United States)

    Oliver, Sandra; Dickson, Kelly

    2016-01-01

    Support for producing systematic reviews about health systems is less well developed than for those about clinical practice. From interviewing policy makers and systematic reviewers we identified institutional mechanisms which bring systematic reviews and policy priorities closer by harnessing organisational and individual motivations, emphasising…

  13. Mathematical models used to inform study design or surveillance systems in infectious diseases: a systematic review.

    Science.gov (United States)

    Herzog, Sereina A; Blaizot, Stéphanie; Hens, Niel

    2017-12-18

    Mathematical models offer the possibility to investigate the infectious disease dynamics over time and may help in informing design of studies. A systematic review was performed in order to determine to what extent mathematical models have been incorporated into the process of planning studies and hence inform study design for infectious diseases transmitted between humans and/or animals. We searched Ovid Medline and two trial registry platforms (Cochrane, WHO) using search terms related to infection, mathematical model, and study design from the earliest dates to October 2016. Eligible publications and registered trials included mathematical models (compartmental, individual-based, or Markov) which were described and used to inform the design of infectious disease studies. We extracted information about the investigated infection, population, model characteristics, and study design. We identified 28 unique publications but no registered trials. Focusing on compartmental and individual-based models we found 12 observational/surveillance studies and 11 clinical trials. Infections studied were equally animal and human infectious diseases for the observational/surveillance studies, while all but one between humans for clinical trials. The mathematical models were used to inform, amongst other things, the required sample size (n = 16), the statistical power (n = 9), the frequency at which samples should be taken (n = 6), and from whom (n = 6). Despite the fact that mathematical models have been advocated to be used at the planning stage of studies or surveillance systems, they are used scarcely. With only one exception, the publications described theoretical studies, hence, not being utilised in real studies.

  14. A systematic comparison of recurrent event models for application to composite endpoints.

    Science.gov (United States)

    Ozga, Ann-Kathrin; Kieser, Meinhard; Rauch, Geraldine

    2018-01-04

    Many clinical trials focus on the comparison of the treatment effect between two or more groups concerning a rarely occurring event. In this situation, showing a relevant effect with an acceptable power requires the observation of a large number of patients over a long period of time. For feasibility issues, it is therefore often considered to include several event types of interest, non-fatal or fatal, and to combine them within a composite endpoint. Commonly, a composite endpoint is analyzed with standard survival analysis techniques by assessing the time to the first occurring event. This approach neglects that an individual may experience more than one event which leads to a loss of information. As an alternative, composite endpoints could be analyzed by models for recurrent events. There exists a number of such models, e.g. regression models based on count data or Cox-based models such as the approaches of Andersen and Gill, Prentice, Williams and Peterson or, Wei, Lin and Weissfeld. Although some of the methods were already compared within the literature there exists no systematic investigation for the special requirements regarding composite endpoints. Within this work a simulation-based comparison of recurrent event models applied to composite endpoints is provided for different realistic clinical trial scenarios. We demonstrate that the Andersen-Gill model and the Prentice- Williams-Petersen models show similar results under various data scenarios whereas the Wei-Lin-Weissfeld model delivers effect estimators which can considerably deviate under commonly met data scenarios. Based on the conducted simulation study, this paper helps to understand the pros and cons of the investigated methods in the context of composite endpoints and provides therefore recommendations for an adequate statistical analysis strategy and a meaningful interpretation of results.

  15. Interventions directed at eating habits and physical activity using the Transtheoretical Model: a systematic review.

    Science.gov (United States)

    Carvalho de Menezes, Mariana; Bedeschi, Lydiane Bragunci; Santos, Luana Caroline Dos; Lopes, Aline Cristine Souza

    2016-09-20

    The multi-behavioral Transtheoretical Model (TTM) addresses multiple behaviors and it is a promising strategy to control multifactorial morbidities, such as chronic diseases. The results obtained using the TTM are positive, but are not consistently methodical. The aim of this study was to systematically review the effectiveness of the Transtheoretical Model in multi-behavioral interventions for changing eating habits and levels of physical activity. A search on PubMed and SciELO databases was performed with inclusion criteria set for intervention studies before 2016 using the Transtheoretical Model for more than one behavior, including eating habits and/or engaging in physical activity. Eighteen studies were identified; there was a predominance of randomized clinical trials, studies conducted in the United States, and the use of the Internet and/or telephone. The selected studies were aimed at changing eating behaviors; five of the studies did not address physical activity. The main results were reduction of fat consumption, an increase in the consumption of fruit and vegetables, and increases in physical activity, which are progressions in the stages of change and weight loss identified by the Transtheoretical Model. However, the studies showed methodological weaknesses, including high participant loss and the omission of information about randomization and blinding.

  16. Systematic prediction error correction: a novel strategy for maintaining the predictive abilities of multivariate calibration models.

    Science.gov (United States)

    Chen, Zeng-Ping; Li, Li-Mei; Yu, Ru-Qin; Littlejohn, David; Nordon, Alison; Morris, Julian; Dann, Alison S; Jeffkins, Paul A; Richardson, Mark D; Stimpson, Sarah L

    2011-01-07

    The development of reliable multivariate calibration models for spectroscopic instruments in on-line/in-line monitoring of chemical and bio-chemical processes is generally difficult, time-consuming and costly. Therefore, it is preferable if calibration models can be used for an extended period, without the need to replace them. However, in many process applications, changes in the instrumental response (e.g. owing to a change of spectrometer) or variations in the measurement conditions (e.g. a change in temperature) can cause a multivariate calibration model to become invalid. In this contribution, a new method, systematic prediction error correction (SPEC), has been developed to maintain the predictive abilities of multivariate calibration models when e.g. the spectrometer or measurement conditions are altered. The performance of the method has been tested on two NIR data sets (one with changes in instrumental responses, the other with variations in experimental conditions) and the outcomes compared with those of some popular methods, i.e. global PLS, univariate slope and bias correction (SBC) and piecewise direct standardization (PDS). The results show that SPEC achieves satisfactory analyte predictions with significantly lower RMSEP values than global PLS and SBC for both data sets, even when only a few standardization samples are used. Furthermore, SPEC is simple to implement and requires less information than PDS, which offers advantages for applications with limited data.

  17. Application of marginal structural models in pharmacoepidemiologic studies: a systematic review.

    Science.gov (United States)

    Yang, Shibing; Eaton, Charles B; Lu, Juan; Lapane, Kate L

    2014-06-01

    We systematically reviewed pharmacoepidemiologic studies published in 2012 that used inverse probability weighted (IPW) estimation of marginal structural models (MSM) to estimate the effect from a time-varying treatment. Potential studies were retrieved through a citation search within Web of Science and a keyword search within PubMed. Eligibility of retrieved studies was independently assessed by at least two reviewers. One reviewer performed data extraction, and a senior epidemiologist confirmed the extracted information for all eligible studies. Twenty pharmacoepidemiologic studies were eligible for data extraction. The majority of reviewed studies did not report whether the positivity assumption was checked. Six studies performed intention-to-treat analyses, but none of them reported adherence levels after treatment initiation. Eight studies chose an as-treated analytic strategy, but only one of them reported modeling the multiphase of treatment use. Almost all studies performing as-treated analyses chose the most recent treatment status as the functional form of exposure in the outcome model. Nearly half of the studies reported that the IPW estimate was substantially different from the estimate derived from a standard regression model. The use of IPW method to control for time-varying confounding is increasing in medical literature. However, reporting of the application of the technique is variable and suboptimal. It may be prudent to develop best practices in reporting complex methods in epidemiologic research. Copyright © 2014 John Wiley & Sons, Ltd.

  18. Extensive and systematic rewiring of histone post-translational modifications in cancer model systems.

    Science.gov (United States)

    Noberini, Roberta; Osti, Daniela; Miccolo, Claudia; Richichi, Cristina; Lupia, Michela; Corleone, Giacomo; Hong, Sung-Pil; Colombo, Piergiuseppe; Pollo, Bianca; Fornasari, Lorenzo; Pruneri, Giancarlo; Magnani, Luca; Cavallaro, Ugo; Chiocca, Susanna; Minucci, Saverio; Pelicci, Giuliana; Bonaldi, Tiziana

    2018-03-29

    Histone post-translational modifications (PTMs) generate a complex combinatorial code that regulates gene expression and nuclear functions, and whose deregulation has been documented in different types of cancers. Therefore, the availability of relevant culture models that can be manipulated and that retain the epigenetic features of the tissue of origin is absolutely crucial for studying the epigenetic mechanisms underlying cancer and testing epigenetic drugs. In this study, we took advantage of quantitative mass spectrometry to comprehensively profile histone PTMs in patient tumor tissues, primary cultures and cell lines from three representative tumor models, breast cancer, glioblastoma and ovarian cancer, revealing an extensive and systematic rewiring of histone marks in cell culture conditions, which includes a decrease of H3K27me2/me3, H3K79me1/me2 and H3K9ac/K14ac, and an increase of H3K36me1/me2. While some changes occur in short-term primary cultures, most of them are instead time-dependent and appear only in long-term cultures. Remarkably, such changes mostly revert in cell line- and primary cell-derived in vivo xenograft models. Taken together, these results support the use of xenografts as the most representative models of in vivo epigenetic processes, suggesting caution when using cultured cells, in particular cell lines and long-term primary cultures, for epigenetic investigations.

  19. Closed system respirometry may underestimate tissue gas exchange and bias the respiratory exchange ratio (RER).

    Science.gov (United States)

    Malte, Christian Lind; Nørgaard, Simon; Wang, Tobias

    2016-02-01

    Closed respirometry is a commonly used method to measure gas exchange in animals due to its apparent simplicity. Typically, the rates of O2 uptake and CO2 excretion (VO2 and VCO2, respectively) are assumed to be in steady state, such that the measured rates of gas exchange equal those at tissue level. In other words, the respiratory gas exchange ratio (RER) is assumed to equal the respiratory quotient (RQ). However, because the gas concentrations change progressively during closure, the animal inspires air with a progressively increasing CO2 concentration and decreasing O2 concentration. These changes will eventually affect gas exchange causing the O2 and CO2 stores within the animal to change. Because of the higher solubility/capacitance of CO2 in the tissues of the body, VCO2 will be more affected than VO2, and we hypothesize therefore that RER will become progressively underestimated as closure time is prolonged. This hypothesis was addressed by a combination of experimental studies involving closed respirometry on ball pythons (Python regius) as well as mathematical models of gas exchange. We show that increased closed duration of the respirometer reduces RER by up to 13%, and these findings may explain previous reports of RER values being below 0.7. Our model reveals that the maximally possible reduction in RER is determined by the storage capacity of the body for CO2 (product of size and specific capacitance) relative to the respirometer storage capacity. Furthermore, modeling also shows that pronounced ventilatory and circulatory response to hypercapnia can alleviate the reduction in RER. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. Systematic Evaluation of Methods for Integration of Transcriptomic Data into Constraint-Based Models of Metabolism

    DEFF Research Database (Denmark)

    Machado, Daniel; Herrgard, Markus

    2014-01-01

    of these methods has not been critically evaluated and compared. This work presents a survey of recently published methods that use transcript levels to try to improve metabolic flux predictions either by generating flux distributions or by creating context-specific models. A subset of these methods...... is then systematically evaluated using published data from three different case studies in E. coli and S. cerevisiae. The flux predictions made by different methods using transcriptomic data are compared against experimentally determined extracellular and intracellular fluxes (from 13C-labeling data). The sensitivity...... of the results to method-specific parameters is also evaluated, as well as their robustness to noise in the data. The results show that none of the methods outperforms the others for all cases. Also, it is observed that for many conditions, the predictions obtained by simple flux balance analysis using growth...

  1. A Systematic Review of the Anxiolytic-Like Effects of Essential Oils in Animal Models

    Directory of Open Access Journals (Sweden)

    Damião Pergentino de Sousa

    2015-10-01

    Full Text Available The clinical efficacy of standardized essential oils (such as Lavender officinalis, in treating anxiety disorders strongly suggests that these natural products are an important candidate source for new anxiolytic drugs. A systematic review of essential oils, their bioactive constituents, and anxiolytic-like activity is conducted. The essential oil with the best profile is Lavendula angustifolia, which has already been tested in controlled clinical trials with positive results. Citrus aurantium using different routes of administration also showed significant effects in several animal models, and was corroborated by different research groups. Other promising essential oils are Citrus sinensis and bergamot oil, which showed certain clinical anxiolytic actions; along with Achillea wilhemsii, Alpinia zerumbet, Citrus aurantium, and Spiranthera odoratissima, which, like Lavendula angustifolia, appear to exert anxiolytic-like effects without GABA/benzodiazepine activity, thus differing in their mechanisms of action from the benzodiazepines. The anxiolytic activity of 25 compounds commonly found in essential oils is also discussed.

  2. Randomised Controlled Trials May Underestimate Drug Effects: Balanced Placebo Trial Design

    Science.gov (United States)

    Lund, Karen; Vase, Lene; Petersen, Gitte L.; Jensen, Troels S.; Finnerup, Nanna B.

    2014-01-01

    Background It is an inherent assumption in randomised controlled trials that the drug effect can be estimated by subtracting the response during placebo from the response during active drug treatment. Objective To test the assumption of additivity. The primary hypothesis was that the total treatment effect is smaller than the sum of the drug effect and the placebo effect. The secondary hypothesis was that non-additivity was most pronounced in participants with large placebo effects. Methods We used a within-subject randomised blinded balanced placebo design and included 48 healthy volunteers (50% males), mean (SD) age 23.4 (6.2) years. Experimental pain was induced by injections of hypertonic saline into the masseter muscle. Participants received four injections with hypertonic saline along with lidocaine or matching placebo in randomised order: A: received hypertonic saline/told hypertonic saline; B: received hypertonic saline+lidocaine/told hypertonic saline; C: received hypertonic saline+placebo/told hypertonic saline+pain killer; D: received hypertonic saline+lidocaine/told hypertonic saline+pain killer. The primary outcome measure was the area under the curve (AUC, mm2) of pain intensity during injections. Results There was a significant difference between the sum of the drug effect and the placebo effect (mean AUC 6279 mm2 (95% CI, 4936–7622)) and the total treatment effect (mean AUC 5455 mm2 (95% CI, 4585–6324)) (P = 0.049). This difference was larger for participants with large versus small placebo effects (P = 0.015), and the difference correlated significantly with the size of the placebo effect (r = 0.65, P = 0.006). Conclusion Although this study examined placebo effects and not the whole placebo response as in randomised controlled trials, it does suggest that the additivity assumption may be incorrect, and that the estimated drug effects in randomised controlled trials may be underestimated, particularly in studies reporting large

  3. Systematic Assessment Through Mathematical Model For Sustainability Reporting In Malaysia Context

    Science.gov (United States)

    Lanang, Wan Nurul Syahirah Wan; Turan, Faiz Mohd; Johan, Kartina

    2017-08-01

    Sustainability assessment have been studied and increasingly recognized as a powerful and valuable tool to measure the performance of sustainability in a company or industry. Nowadays, there are many existing tools that the users can use for sustainable development. There are various initiatives exists on tools for sustainable development, though most of the tools focused on environmental, economy and social aspects. Using the Green Project Management (GPM) P5 concept that suggests the firms not only needs to engage in mainly 3Ps principle: planet, profit, people responsible behaviours, but also, product and process need to be included in the practices, this study will introduce a new mathematical model for assessing the level of sustainability practice in the company. Based on multiple case studies, involving in-depth interviews with senior directors, feedback from experts, and previous engineering report, a systematic approach is done with the aims to obtain the respective data from the feedbacks and to be developed into a new mathematical model. By reviewing on the methodology of this research it comprises of several phases where it starts with the analyzation of the parameters and criteria selection according to the Malaysian context of industry. Moving on to the next step is data analysis involving regression and finally the normalisation process will be done to determine the result of this research either succeeded or not. Lastly, this study is expected to provide a clear guideline to any company or organization to assimilate the sustainability assessment in their development stage. In future, the better understanding towards the sustainability assessment is attained to be aligned unitedly in order to integrated the process approach into the systematic approach for the sustainability assessment.

  4. An appointment-based model to systematically assess and administer vaccinations.

    Science.gov (United States)

    Luder, Heidi R; Kunze, Natalie; Heaton, Pamela C; Frede, Stacey M

    2018-03-27

    To incorporate the assessment of vaccination status and administration of vaccines in an appointment-based model (ABM) and measure the impact on vaccinations administered and patient and pharmacist satisfaction with the appointment-based model. An ABM was implemented to systematically assess vaccination status and administer vaccines. Patients made an appointment to pick up synchronized prescriptions, and pharmacists assessed vaccination histories and administered vaccinations during the appointment. In addition, pharmacists could access the statewide immunization information system to objectively determine vaccination histories and document administered vaccines. This project was conducted at 24 Kroger Pharmacies in the Cincinnati-Dayton Area. Any patient filling more than 1 maintenance medication was eligible for the ABM program. Pharmacists were encouraged to target patients at high risk for medication problems and vaccine-preventable diseases, including patients 60 years of age or older with more than 5 medications and high-risk disease states such as diabetes, asthma, and chronic obstructive pulmonary disease. Pharmacies were randomized, and an a priori analysis was conducted to ensure that the 24 intervention and 78 control stores were similar at baseline. Postimplementation data on the mean number of vaccines per store were compared between the intervention stores and the control stores from September 2014 through December 2015. Patient and pharmacist satisfaction with the ABM was assessed via surveys. The pharmacist vaccine assessment as part of the ABM program showed higher overall mean vaccinations per store compared with the control group during the project period (1810.71 ± 500.88 vs. 1455.09 ± 754.43; P = 0.01). Patients and pharmacists felt that the ABM program facilitated vaccine discussions. The ABM program with a focus on vaccinations allowed pharmacists to systematically assess patient vaccination histories and administer vaccines in the

  5. Health literacy in childhood and youth: a systematic review of definitions and models

    Directory of Open Access Journals (Sweden)

    Janine Bröder

    2017-04-01

    Full Text Available Abstract Background Children and young people constitute a core target group for health literacy research and practice: during childhood and youth, fundamental cognitive, physical and emotional development processes take place and health-related behaviours and skills develop. However, there is limited knowledge and academic consensus regarding the abilities and knowledge a child or young person should possess for making sound health decisions. The research presented in this review addresses this gap by providing an overview and synthesis of current understandings of health literacy in childhood and youth. Furthermore, the authors aim to understand to what extent available models capture the unique needs and characteristics of children and young people. Method Six databases were systematically searched with relevant search terms in English and German. Of the n = 1492 publications identified, N = 1021 entered the abstract screening and N = 340 full-texts were screened for eligibility. A total of 30 articles, which defined or conceptualized generic health literacy for a target population of 18 years or younger, were selected for a four-step inductive content analysis. Results The systematic review of the literature identified 12 definitions and 21 models that have been specifically developed for children and young people. In the literature, health literacy in children and young people is described as comprising variable sets of key dimensions, each appearing as a cluster of related abilities, skills, commitments, and knowledge that enable a person to approach health information competently and effectively and to derive at health-promoting decisions and actions. Discussion Identified definitions and models are very heterogeneous, depicting health literacy as multidimensional, complex construct. Moreover, health literacy is conceptualized as an action competence, with a strong focus on personal attributes, while also recognising its

  6. Characteristics of Indigenous primary health care service delivery models: a systematic scoping review.

    Science.gov (United States)

    Harfield, Stephen G; Davy, Carol; McArthur, Alexa; Munn, Zachary; Brown, Alex; Brown, Ngiare

    2018-01-25

    Indigenous populations have poorer health outcomes compared to their non-Indigenous counterparts. The evolution of Indigenous primary health care services arose from mainstream health services being unable to adequately meet the needs of Indigenous communities and Indigenous peoples often being excluded and marginalised from mainstream health services. Part of the solution has been to establish Indigenous specific primary health care services, for and managed by Indigenous peoples. There are a number of reasons why Indigenous primary health care services are more likely than mainstream services to improve the health of Indigenous communities. Their success is partly due to the fact that they often provide comprehensive programs that incorporate treatment and management, prevention and health promotion, as well as addressing the social determinants of health. However, there are gaps in the evidence base including the characteristics that contribute to the success of Indigenous primary health care services in providing comprehensive primary health care. This systematic scoping review aims to identify the characteristics of Indigenous primary health care service delivery models. This systematic scoping review was led by an Aboriginal researcher, using the Joanna Briggs Institute Scoping Review Methodology. All published peer-reviewed and grey literature indexed in PubMed, EBSCO CINAHL, Embase, Informit, Mednar, and Trove databases from September 1978 to May 2015 were reviewed for inclusion. Studies were included if they describe the characteristics of service delivery models implemented within an Indigenous primary health care service. Sixty-two studies met the inclusion criteria. Data were extracted and then thematically analysed to identify the characteristics of Indigenous PHC service delivery models. Culture was the most prominent characteristic underpinning all of the other seven characteristics which were identified - accessible health services, community

  7. Health literacy in childhood and youth: a systematic review of definitions and models.

    Science.gov (United States)

    Bröder, Janine; Okan, Orkan; Bauer, Ullrich; Bruland, Dirk; Schlupp, Sandra; Bollweg, Torsten M; Saboga-Nunes, Luis; Bond, Emma; Sørensen, Kristine; Bitzer, Eva-Maria; Jordan, Susanne; Domanska, Olga; Firnges, Christiane; Carvalho, Graça S; Bittlingmayer, Uwe H; Levin-Zamir, Diane; Pelikan, Jürgen; Sahrai, Diana; Lenz, Albert; Wahl, Patricia; Thomas, Malcolm; Kessl, Fabian; Pinheiro, Paulo

    2017-04-26

    Children and young people constitute a core target group for health literacy research and practice: during childhood and youth, fundamental cognitive, physical and emotional development processes take place and health-related behaviours and skills develop. However, there is limited knowledge and academic consensus regarding the abilities and knowledge a child or young person should possess for making sound health decisions. The research presented in this review addresses this gap by providing an overview and synthesis of current understandings of health literacy in childhood and youth. Furthermore, the authors aim to understand to what extent available models capture the unique needs and characteristics of children and young people. Six databases were systematically searched with relevant search terms in English and German. Of the n = 1492 publications identified, N = 1021 entered the abstract screening and N = 340 full-texts were screened for eligibility. A total of 30 articles, which defined or conceptualized generic health literacy for a target population of 18 years or younger, were selected for a four-step inductive content analysis. The systematic review of the literature identified 12 definitions and 21 models that have been specifically developed for children and young people. In the literature, health literacy in children and young people is described as comprising variable sets of key dimensions, each appearing as a cluster of related abilities, skills, commitments, and knowledge that enable a person to approach health information competently and effectively and to derive at health-promoting decisions and actions. Identified definitions and models are very heterogeneous, depicting health literacy as multidimensional, complex construct. Moreover, health literacy is conceptualized as an action competence, with a strong focus on personal attributes, while also recognising its interrelatedness with social and contextual determinants. Life phase

  8. Academic self-concept, learning motivation, and test anxiety of the underestimated student.

    Science.gov (United States)

    Urhahne, Detlef; Chao, Sheng-Han; Florineth, Maria Luise; Luttenberger, Silke; Paechter, Manuela

    2011-03-01

    BACKGROUND. Teachers' judgments of student performance on a standardized achievement test often result in an overestimation of students' abilities. In the majority of cases, a larger group of overestimated students and a smaller group of underestimated students are formed by these judgments. AIMS. In this research study, the consequences of the underestimation of students' mathematical performance potential were examined. SAMPLE. Two hundred and thirty-five fourth grade students and their fourteen mathematics teachers took part in the investigation. METHOD. Students worked on a standardized mathematics achievement test and completed a self-description questionnaire about motivation and affect. Teachers estimated each individual student's potential with regard to mathematics test performance as well as students' expectancy for success, level of aspiration, academic self-concept, learning motivation, and test anxiety. The differences between teachers' judgments on students' test performance and students' actual performance were used to build groups of underestimated and overestimated students. RESULTS. Underestimated students displayed equal levels of test performance, learning motivation, and level of aspiration in comparison with overestimated students, but had lower expectancy for success, lower academic self-concept, and experienced more test anxiety. Teachers expected that underestimated students would receive lower grades on the next mathematics test, believed that students were satisfied with lower grades, and assumed that the students have weaker learning motivation than their overestimated classmates. CONCLUSION. Teachers' judgment error was not confined to test performance but generalized to motivational and affective traits of the students. © 2010 The British Psychological Society.

  9. Simple way to avoid underestimating uncertainties of the evaluated values for sets of consistent data: a proposal for an improvement of the evaluations

    International Nuclear Information System (INIS)

    Chechev, V.P.

    2001-01-01

    To avoid underestimating the uncertainty of the evaluated values for sets of consistent data the following rule is proposed: if the smallest of the input measurement uncertainties (σ min ) is more than the uncertainty obtained from statistical data processing, the σ min should be used as a final uncertainty of the evaluated value. This rule is justified by the fact that almost any measurement is indirect and the total uncertainty of any precise measurement includes mainly the systematic error of the measurement method. Exceptions can be only for measured data obtained by essentially different methods (for example, half life measurements by calorimetry and specific activity determination)

  10. Dynamic modeling approaches to characterize the functioning of health systems: A systematic review of the literature.

    Science.gov (United States)

    Chang, Angela Y; Ogbuoji, Osondu; Atun, Rifat; Verguet, Stéphane

    2017-12-01

    Universal Health Coverage (UHC) is one of the targets for the United Nations Sustainable Development Goal 3. The impetus for UHC has led to an increased demand for time-sensitive tools to enhance our knowledge of how health systems function and to evaluate impact of system interventions. We define the field of "health system modeling" (HSM) as an area of research where dynamic mathematical models can be designed in order to describe, predict, and quantitatively capture the functioning of health systems. HSM can be used to explore the dynamic relationships among different system components, including organizational design, financing and other resources (such as investments in resources and supply chain management systems) - what we call "inputs" - on access, coverage, and quality of care - what we call "outputs", toward improved health system "outcomes", namely increased levels and fairer distributions of population health and financial risk protection. We undertook a systematic review to identify the existing approaches used in HSM. We identified "systems thinking" - a conceptual and qualitative description of the critical interactions within a health system - as an important underlying precursor to HSM, and collated a critical collection of such articles. We then reviewed and categorized articles from two schools of thoughts: "system dynamics" (SD)" and "susceptible-infected-recovered-plus" (SIR+). SD emphasizes the notion of accumulations of stocks in the system, inflows and outflows, and causal feedback structure to predict intended and unintended consequences of policy interventions. The SIR + models link a typical disease transmission model with another that captures certain aspects of the system that impact the outcomes of the main model. These existing methods provide critical insights in informing the design of HSM, and provide a departure point to extend this research agenda. We highlight the opportunity to advance modeling methods to further understand

  11. Correction Model of BeiDou Code Systematic Multipath Errors and Its Impacts on Single-frequency PPP

    Directory of Open Access Journals (Sweden)

    WANG Jie

    2017-07-01

    Full Text Available There are systematic multipath errors on BeiDou code measurements, which are range from several decimeters to larger than 1 meter. They can be divided into two categories, which are systematic variances in IGSO/MEO code measurement and in GEO code measurement. In this contribution, a methodology of correcting BeiDou GEO code multipath is proposed base on Kalman filter algorithm. The standard deviation of GEO MP Series decreases about 10%~16% after correction. The weight of code in single-frequency PPP is great, therefore, code systematic multipath errors have impact on single-frequency PPP. Our analysis indicate that about 1 m bias will be caused by these systematic errors. Then, we evaluated the improvement of single-frequency PPP accuracy after code multipath correction. The systematic errors of GEO code measurements are corrected by applying our proposed Kalman filter method. The systematic errors of IGSO and MEO code measurements are corrected by applying elevation-dependent model proposed by Wanninger and Beer. Ten days observations of four MGEX (Multi-GNSS Experiment stations are processed. The results indicate that the single-frequency PPP accuracy can be improved remarkably by applying code multipath correction. The accuracy in up direction can be improved by 65% after IGSO and MEO code multipath correction. By applying GEO code multipath correction, the accuracy in up direction can be further improved by 15%.

  12. Scaling up depot medroxyprogesterone acetate (DMPA): a systematic literature review illustrating the AIDED model.

    Science.gov (United States)

    Curry, Leslie; Taylor, Lauren; Pallas, Sarah Wood; Cherlin, Emily; Pérez-Escamilla, Rafael; Bradley, Elizabeth H

    2013-08-02

    Use of depot medroxyprogesterone acetate (DMPA), often known by the brand name Depo-Provera, has increased globally, particularly in multiple low- and middle-income countries (LMICs). As a reproductive health technology that has scaled up in diverse contexts, DMPA is an exemplar product innovation with which to illustrate the utility of the AIDED model for scaling up family health innovations. We conducted a systematic review of the enabling factors and barriers to scaling up DMPA use in LMICs. We searched 11 electronic databases for academic literature published through January 2013 (n = 284 articles), and grey literature from major health organizations. We applied exclusion criteria to identify relevant articles from peer-reviewed (n = 10) and grey literature (n = 9), extracting data on scale up of DMPA in 13 countries. We then mapped the resulting factors to the five AIDED model components: ASSESS, INNOVATE, DEVELOP, ENGAGE, and DEVOLVE. The final sample of sources included studies representing variation in geographies and methodologies. We identified 15 enabling factors and 10 barriers to dissemination, diffusion, scale up, and/or sustainability of DMPA use. The greatest number of factors were mapped to the ASSESS, DEVELOP, and ENGAGE components. Findings offer early empirical support for the AIDED model, and provide insights into scale up of DMPA that may be relevant for other family planning product innovations.

  13. Underestimated seismic hazard in the south of the Issyk-Kul Lake region (northern Tian Shan

    Directory of Open Access Journals (Sweden)

    A.M. Korzhenkov

    2017-05-01

    Full Text Available The Tian Shan Mountains were formed in the result of the India–Eurasia collision, which leads to creation of contrast high-mountain relief and world known seismic activity. The seismic catastrophes, recorded instrumentally, have occurred to the north of the Issyk-Kul Lake region. There are also known significant earthquakes with magnitude being about 7 in western and eastern parts of the mentioned lake region. Only in the south of the Issyk-Kul depression the strong earthquakes recorded by the seismic network were not known. Our recent study in the south of the Issyk-Kul Lake region has revealed numerous active tectonic structures related to South Issyk-Kul Fault: faults and folds, responsible for strong earthquakes' occurrence. These were historical and paleoseismic deformations which led to changes in relief: fault scarps and significant rockslides. We have also found spectacular deformations in archeological monuments. All these deformations testify the location of epicentral areas of two strong historic (about 11th and 16th (? centuries AD and paleoearthquakes (Holocene and Late Pleistocene. Magnitude of ancient seismic events, according to parameters of the revealed fault scarps, were Ms ≥ 7 and seismic intensity I ≥ IX. All revealed seismic deformations are located to adyrs (piedmonts of the Terskey Ala-Too range bordered of the Issyk-Kul Lake depression in the south. Their formation is described by the model of a fault which rupture plane becomes shallower southward. This model is complicated by the presence of reverse thrusts. Here, we should admit the existence of a single zone of South Issyk-Kul Fault which is a long-lived feature which separates the structures with the different regime of movements during the Neotectonic time. All obtained data led us to a conclusion of significant underestimation of the seismic hazard in southern Issyk-Kul Lake region.

  14. Disk Masses around Solar-mass Stars are Underestimated by CO Observations

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Mo; Evans II, Neal J. [Astronomy Department, University of Texas, 2515 Speedway, Stop C1400, Austin, TX 78712 (United States); Dodson-Robinson, Sarah E. [University of Delaware, Department of Physics and Astronomy, 217 Sharp Lab, Newark, DE 19716 (United States); Willacy, Karen; Turner, Neal J. [Mail Stop 169-506, Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109 (United States)

    2017-05-20

    Gas in protostellar disks provides the raw material for giant planet formation and controls the dynamics of the planetesimal-building dust grains. Accurate gas mass measurements help map the observed properties of planet-forming disks onto the formation environments of known exoplanets. Rare isotopologues of carbon monoxide (CO) have been used as gas mass tracers for disks in the Lupus star-forming region, with an assumed interstellar CO/H{sub 2} abundance ratio. Unfortunately, observations of T-Tauri disks show that CO abundance is not interstellar, a finding reproduced by models that show CO abundance decreasing both with distance from the star and as a function of time. Here, we present radiative transfer simulations that assess the accuracy of CO-based disk mass measurements. We find that the combination of CO chemical depletion in the outer disk and optically thick emission from the inner disk leads observers to underestimate gas mass by more than an order of magnitude if they use the standard assumptions of interstellar CO/H{sub 2} ratio and optically thin emission. Furthermore, CO abundance changes on million-year timescales, introducing an age/mass degeneracy into observations. To reach a factor of a few accuracy for CO-based disk mass measurements, we suggest that observers and modelers adopt the following strategies: (1) select low- J transitions; (2) observe multiple CO isotopologues and use either intensity ratios or normalized line profiles to diagnose CO chemical depletion; and (3) use spatially resolved observations to measure the CO-abundance distribution.

  15. Misery Has More Company Than People Think: Underestimating the Prevalence of Others’ Negative Emotions

    Science.gov (United States)

    Jordan, Alexander H.; Monin, Benoît; Dweck, Carol S.; Lovett, Benjamin J.; John, Oliver P.; Gross, James J.

    2014-01-01

    Four studies document underestimations of the prevalence of others’ negative emotions, and suggest causes and correlates of these erroneous perceptions. In Study 1A, participants reported that their negative emotions were more private or hidden than their positive emotions; in Study 1B, participants underestimated the peer prevalence of common negative, but not positive, experiences described in Study 1A. In Study 2, people underestimated negative emotions and overestimated positive emotions even for well-known peers, and this effect was partially mediated by the degree to which those peers reported suppression of negative (vs. positive) emotions. Study 3 showed that lower estimations of the prevalence of negative emotional experiences predicted greater loneliness and rumination and lower life satisfaction, and that higher estimations for positive emotional experiences predicted lower life satisfaction. Taken together, these studies suggest that people may think they are more alone in their emotional difficulties than they really are. PMID:21177878

  16. Maternal Underestimation of Child's Weight Status and Health Behaviors as Risk Factors for Overweight in Children.

    Science.gov (United States)

    Vallejo, Maite; Cortes-Rodríguez, Beatriz A; Colin-Ramirez, Eloisa

    2015-01-01

    To evaluate children's risk of being overweight associated with maternal underestimation of weight status and health behaviors. One hundred forty mother-child dyads were included. Children whose weight status was underestimated by their mothers were at greater risks of being overweight compared to those whose weigh status was correctly perceived (adjusted OR 2.31, 95% CI 1.11-4.81). Less television viewing time was associated with a 63% reduced risk of being overweight (adjusted OR .37, 95% CI .17-.83). Maternal underestimation of weight status was common among overweight and normal-weight children, and it was associated with an increased children's risk of being overweight. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. Animal models of bone cancer pain: systematic review and meta-analyses.

    Science.gov (United States)

    Currie, Gillian L; Delaney, Ada; Bennett, Michael I; Dickenson, Anthony H; Egan, Kieren J; Vesterinen, Hanna M; Sena, Emily S; Macleod, Malcolm R; Colvin, Lesley A; Fallon, Marie T

    2013-06-01

    Pain can significantly decrease the quality of life of patients with advanced cancer. Current treatment strategies often provide inadequate analgesia and unacceptable side effects. Animal models of bone cancer pain are used in the development of novel pharmacological approaches. Here we conducted a systematic review and meta-analysis of publications describing in vivo modelling of bone cancer pain in which behavioural, general health, macroscopic, histological, biochemical, or electrophysiological outcomes were reported and compared to appropriate controls. In all, 150 publications met our inclusion criteria, describing 38 different models of bone cancer pain. Reported methodological quality was low; only 31% of publications reported blinded assessment of outcome, and 11% reported random allocation to group. No publication reported a sample size calculation. Studies that reported measures to reduce bias reported smaller differences in behavioural outcomes between tumour-bearing and control animals, and studies that presented a statement regarding a conflict of interest reported larger differences in behavioural outcomes. Larger differences in behavioural outcomes were reported in female animals, when cancer cells were injected into either the tibia or femur, and when MatLyLu prostate or Lewis Lung cancer cells were used. Mechanical-evoked pain behaviours were most commonly reported; however, the largest difference was observed in spontaneous pain behaviours. In the spinal cord astrocyte activation and increased levels of Substance P receptor internalisation, c-Fos, dynorphin, tumor necrosis factor-α and interleukin-1β have been reported in bone cancer pain models, suggesting several potential therapeutic targets. However, the translational impact of animal models on clinical pain research could be enhanced by improving methodological quality. Copyright © 2013. Published by Elsevier B.V.

  18. An integrative model of patient-centeredness - a systematic review and concept analysis.

    Directory of Open Access Journals (Sweden)

    Isabelle Scholl

    Full Text Available Existing models of patient-centeredness reveal a lack of conceptual clarity. This results in a heterogeneous use of the term, unclear measurement dimensions, inconsistent results regarding the effectiveness of patient-centered interventions, and finally in difficulties in implementing patient-centered care. The aim of this systematic review was to identify the different dimensions of patient-centeredness described in the literature and to propose an integrative model of patient-centeredness based on these results.Protocol driven search in five databases, combined with a comprehensive secondary search strategy. All articles that include a definition of patient-centeredness were eligible for inclusion in the review and subject to subsequent content analysis. Two researchers independently first screened titles and abstracts, then assessed full texts for eligibility. In each article the given definition of patient-centeredness was coded independently by two researchers. We discussed codes within the research team and condensed them into an integrative model of patient-centeredness.4707 records were identified through primary and secondary search, of which 706 were retained after screening of titles and abstracts. 417 articles (59% contained a definition of patient-centeredness and were coded. 15 dimensions of patient-centeredness were identified: essential characteristics of clinician, clinician-patient relationship, clinician-patient communication, patient as unique person, biopsychosocial perspective, patient information, patient involvement in care, involvement of family and friends, patient empowerment, physical support, emotional support, integration of medical and non-medical care, teamwork and teambuilding, access to care, coordination and continuity of care. In the resulting integrative model the dimensions were mapped onto different levels of care.The proposed integrative model of patient-centeredness allows different stakeholders to speak

  19. Do small samples underestimate mean abundance? It depends on what type of bias we consider.

    Science.gov (United States)

    Reiczigel, Jeno; Rozsa, Lajos

    2017-07-26

    Former authors claimed that, due to parasites' aggregated distribution, small samples underestimate the true population mean abundance. Here we show that this claim is false or true, depending on what is meant by 'underestimate' or, mathematically speaking, how we define 'bias'. The 'how often' and 'on average' views lead to different conclusions because sample mean abundance itself exhibits an aggregated distribution: most often it falls slightly below the true population mean, while sometimes greatly exceeds it. Since the several small negative deviations are compensated by a few greater positive ones, the average of sample means approximates the true population mean.

  20. Calorie Underestimation When Buying High-Calorie Beverages in Fast-Food Contexts.

    Science.gov (United States)

    Franckle, Rebecca L; Block, Jason P; Roberto, Christina A

    2016-07-01

    We asked 1877 adults and 1178 adolescents visiting 89 fast-food restaurants in New England in 2010 and 2011 to estimate calories purchased. Calorie underestimation was greater among those purchasing a high-calorie beverage than among those who did not (adults: 324 ±698 vs 102 ±591 calories; adolescents: 360 ±602 vs 198 ±509 calories). This difference remained significant for adults but not adolescents after adjusting for total calories purchased. Purchasing high-calorie beverages may uniquely contribute to calorie underestimation among adults.

  1. Calorie Underestimation When Buying High-Calorie Beverages in Fast-Food Contexts

    Science.gov (United States)

    Block, Jason P.; Roberto, Christina A.

    2016-01-01

    We asked 1877 adults and 1178 adolescents visiting 89 fast-food restaurants in New England in 2010 and 2011 to estimate calories purchased. Calorie underestimation was greater among those purchasing a high-calorie beverage than among those who did not (adults: 324 ±698 vs 102 ±591 calories; adolescents: 360 ±602 vs 198 ±509 calories). This difference remained significant for adults but not adolescents after adjusting for total calories purchased. Purchasing high-calorie beverages may uniquely contribute to calorie underestimation among adults. PMID:27196648

  2. Disassembly for remanufacturing: A systematic literature review, new model development and future research needs

    International Nuclear Information System (INIS)

    Priyono, A.; Ijomah, W.; Bititci, U.

    2016-01-01

    Purpose: Disassembly is an important process that distinguishes remanufacturing from conventional manufacturing. It is a unique process that becomes focus of investigation from many scholars. Yet, most scholars investigate disassembly from technical and operational standpoint that lack of strategic perspective. This paper attempts to fill this gap by looking at disassembly from a strategic perspective by considering organisational characteristics, process choices and product attributes. To be more specific, this paper has three objectives. First, to gain understanding what has been done, and what need to be done in the field of disassembly in remanufacturing. Second, to conduct a systematic literature review for identifying the factors affecting disassembly for remanufacturing. Third, to propose a new model of disassembly for remanufacturing and also to provide avenues for future research. Design/methodology/approach: This study used a systematic literature review method. A series of steps were undertaken during the review. The study was started with determining the purpose of the study, selecting appropriate keywords, and reducing the selected papers using a number of criteria. A deeper analysis was carried out on the final paper that meets the criteria for this review. Findings: There are two main findings of this study. First, a list of factors affecting disassembly in remanufacturing is identified. The factors can be categorised into three groups: organisational factors, process choices and product attributes. Second, using factors that have been identified, a new model of disassembly process for remanufacturing is developed. Current studies only consider disassembly as a physical activity to break down products into components. In the new model, disassembly is viewed as a process that converts into into output, which consist of a series of steps. Research limitations/implications: The opportunities for future research include: the need to develop an index of

  3. Disassembly for remanufacturing: A systematic literature review, new model development and future research needs

    Directory of Open Access Journals (Sweden)

    Anjar Priyono

    2016-11-01

    Full Text Available Purpose: Disassembly is an important process that distinguishes remanufacturing from conventional manufacturing. It is a unique process that becomes focus of investigation from many scholars. Yet, most scholars investigate disassembly from technical and operational standpoint that lack of strategic perspective. This paper attempts to fill this gap by looking at disassembly from a strategic perspective by considering organisational characteristics, process choices and product attributes. To be more specific, this paper has three objectives. First, to gain understanding what has been done, and what need to be done in the field of disassembly in remanufacturing. Second, to conduct a systematic literature review for identifying the factors affecting disassembly for remanufacturing. Third, to propose a new model of disassembly for remanufacturing and also to provide avenues for future research. Design/methodology/approach: This study used a systematic literature review method. A series of steps were undertaken during the review. The study was started with determining the purpose of the study, selecting appropriate keywords, and reducing the selected papers using a number of criteria. A deeper analysis was carried out on the final paper that meets the criteria for this review. Findings: There are two main findings of this study. First, a list of factors affecting disassembly in remanufacturing is identified. The factors can be categorised into three groups: organisational factors, process choices and product attributes. Second, using factors that have been identified, a new model of disassembly process for remanufacturing is developed. Current studies only consider disassembly as a physical activity to break down products into components. In the new model, disassembly is viewed as a process that converts into into output, which consist of a series of steps. Research limitations/implications: The opportunities for future research include: the need to

  4. Disassembly for remanufacturing: A systematic literature review, new model development and future research needs

    Energy Technology Data Exchange (ETDEWEB)

    Priyono, A.; Ijomah, W.; Bititci, U.

    2016-07-01

    Purpose: Disassembly is an important process that distinguishes remanufacturing from conventional manufacturing. It is a unique process that becomes focus of investigation from many scholars. Yet, most scholars investigate disassembly from technical and operational standpoint that lack of strategic perspective. This paper attempts to fill this gap by looking at disassembly from a strategic perspective by considering organisational characteristics, process choices and product attributes. To be more specific, this paper has three objectives. First, to gain understanding what has been done, and what need to be done in the field of disassembly in remanufacturing. Second, to conduct a systematic literature review for identifying the factors affecting disassembly for remanufacturing. Third, to propose a new model of disassembly for remanufacturing and also to provide avenues for future research. Design/methodology/approach: This study used a systematic literature review method. A series of steps were undertaken during the review. The study was started with determining the purpose of the study, selecting appropriate keywords, and reducing the selected papers using a number of criteria. A deeper analysis was carried out on the final paper that meets the criteria for this review. Findings: There are two main findings of this study. First, a list of factors affecting disassembly in remanufacturing is identified. The factors can be categorised into three groups: organisational factors, process choices and product attributes. Second, using factors that have been identified, a new model of disassembly process for remanufacturing is developed. Current studies only consider disassembly as a physical activity to break down products into components. In the new model, disassembly is viewed as a process that converts into into output, which consist of a series of steps. Research limitations/implications: The opportunities for future research include: the need to develop an index of

  5. An evaluation of a model for the systematic documentation of hospital based health promotion activities: results from a multicentre study

    DEFF Research Database (Denmark)

    Tønnesen, Hanne; Christensen, Mette E; Groene, Oliver

    2007-01-01

    of two parts; first part includes motivational counselling (7 codes) and the second part comprehends intervention, rehabilitation and after treatment (8 codes).The objective was to evaluate in an international study the usefulness, applicability and sufficiency of a simple model for the systematic...

  6. Systematic characterization of myocardial inflammation, repair, and remodeling in a mouse model of reperfused myocardial infarction.

    Science.gov (United States)

    Christia, Panagiota; Bujak, Marcin; Gonzalez-Quesada, Carlos; Chen, Wei; Dobaczewski, Marcin; Reddy, Anilkumar; Frangogiannis, Nikolaos G

    2013-08-01

    Mouse models of myocardial infarction are essential tools for the study of cardiac injury, repair, and remodeling. Our current investigation establishes a systematic approach for quantitative evaluation of the inflammatory and reparative response, cardiac function, and geometry in a mouse model of reperfused myocardial infarction. Reperfused mouse infarcts exhibited marked induction of inflammatory cytokines that peaked after 6 hr of reperfusion. In the infarcted heart, scar contraction and chamber dilation continued for at least 28 days after reperfusion; infarct maturation was associated with marked thinning of the scar, accompanied by volume loss and rapid clearance of cellular elements. Echocardiographic measurements of end-diastolic dimensions correlated well with morphometric assessment of dilative remodeling in perfusion-fixed hearts. Hemodynamic monitoring was used to quantitatively assess systolic and diastolic function; the severity of diastolic dysfunction following myocardial infarction correlated with cardiomyocyte hypertrophy and infarct collagen content. Expression of molecular mediators of inflammation and cellular infiltration needs to be investigated during the first 72 hr, whereas assessment of dilative remodeling requires measurement of geometric parameters for at least four weeks after the acute event. Rapid initiation and resolution of the inflammatory response, accelerated scar maturation, and extensive infarct volume loss are important characteristics of infarct healing in mice.

  7. Effects of Photobiomodulation Therapy on Oxidative Stress in Muscle Injury Animal Models: A Systematic Review

    Directory of Open Access Journals (Sweden)

    Solange Almeida dos Santos

    2017-01-01

    Full Text Available This systematic review was performed to identify the role of photobiomodulation therapy on experimental muscle injury models linked to induce oxidative stress. EMBASE, PubMed, and CINAHL were searched for studies published from January 2006 to January 2016 in the areas of laser and oxidative stress. Any animal model using photobiomodulation therapy to modulate oxidative stress was included in analysis. Eight studies were selected from 68 original articles targeted on laser irradiation and oxidative stress. Articles were critically assessed by two independent raters with a structured tool for rating the research quality. Although the small number of studies limits conclusions, the current literature indicates that photobiomodulation therapy can be an effective short-term approach to reduce oxidative stress markers (e.g., thiobarbituric acid-reactive and to increase antioxidant substances (e.g., catalase, glutathione peroxidase, and superoxide dismutase. However, there is a nonuniformity in the terminology used to describe the parameters and dose for low-level laser treatment.

  8. Integration of statistical modeling and high-content microscopy to systematically investigate cell-substrate interactions.

    Science.gov (United States)

    Chen, Wen Li Kelly; Likhitpanichkul, Morakot; Ho, Anthony; Simmons, Craig A

    2010-03-01

    Cell-substrate interactions are multifaceted, involving the integration of various physical and biochemical signals. The interactions among these microenvironmental factors cannot be facilely elucidated and quantified by conventional experimentation, and necessitate multifactorial strategies. Here we describe an approach that integrates statistical design and analysis of experiments with automated microscopy to systematically investigate the combinatorial effects of substrate-derived stimuli (substrate stiffness and matrix protein concentration) on mesenchymal stem cell (MSC) spreading, proliferation and osteogenic differentiation. C3H10T1/2 cells were grown on type I collagen- or fibronectin-coated polyacrylamide hydrogels with tunable mechanical properties. Experimental conditions, which were defined according to central composite design, consisted of specific permutations of substrate stiffness (3-144 kPa) and adhesion protein concentration (7-520 microg/mL). Spreading area, BrdU incorporation and Runx2 nuclear translocation were quantified using high-content microscopy and modeled as mathematical functions of substrate stiffness and protein concentration. The resulting response surfaces revealed distinct patterns of protein-specific, substrate stiffness-dependent modulation of MSC proliferation and differentiation, demonstrating the advantage of statistical modeling in the detection and description of higher-order cellular responses. In a broader context, this approach can be adapted to study other types of cell-material interactions and can facilitate the efficient screening and optimization of substrate properties for applications involving cell-material interfaces. Copyright 2009 Elsevier Ltd. All rights reserved.

  9. The JOINT model of nurse absenteeism and turnover: a systematic review.

    Science.gov (United States)

    Daouk-Öyry, Lina; Anouze, Abdel-Latef; Otaki, Farah; Dumit, Nuhad Yazbik; Osman, Ibrahim

    2014-01-01

    Absenteeism and turnover among healthcare workers have a significant impact on overall healthcare system performance. The literature captures variables from different levels of measurement and analysis as being associated with attendance behavior among nurses. Yet, it remains unclear how variables from different contextual levels interact to impact nurses' attendance behaviors. The purpose of this review is to develop an integrative multilevel framework that optimizes our understanding of absenteeism and turnover among nurses in hospital settings. We therefore systematically examine English-only studies retrieved from two major databases, PubMed and CINAHL Plus and published between January, 2007 and January, 2013 (inclusive). Our review led to the identification of 7619 articles out of which 41 matched the inclusion criteria. The analysis yielded a total of 91 antecedent variables and 12 outcome variables for turnover, and 29 antecedent variables and 9 outcome variables for absenteeism. The various manifested variables were analyzed using content analysis and grouped into 11 categories, and further into five main factors: Job, Organization, Individual, National and inTerpersonal (JOINT). Thus, we propose the JOINT multilevel conceptual model for investigating absenteeism and turnover among nurses. The JOINT model can be adapted by researchers for fitting their hypothesized multilevel relationships. It can also be used by nursing managers as a lens for holistically managing nurses' attendance behaviors. Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. Evaluating the effectiveness of health belief model interventions in improving adherence: a systematic review.

    Science.gov (United States)

    Jones, Christina Jane; Smith, Helen; Llewellyn, Carrie

    2014-01-01

    Lack of adherence to health-promoting advice challenges the successful prevention and management of many conditions. The Health Belief Model (HBM) was developed in 1966 to predict health-promoting behaviour and has been used in patients with wide variety of disease. The HBM has also been used to inform the development of interventions to improve health behaviours. Several reviews have documented the HBM's performance in predicting behaviour, but no review has addressed its utility in the design of interventions or the efficacy of these interventions. A systematic review was conducted to identify interventional studies which use the HBM as the theoretical basis for intervention design. The HBM has been used continuously in the development of behaviour change interventions for 40 years. Of 18 eligible studies, 14 (78%) reported significant improvements in adherence, with 7 (39%) showing moderate to large effects. However, only six studies used the HBM in its entirety and five different studies measured health beliefs as outcomes. Intervention success appeared to be unrelated to HBM construct addressed challenging the utility of this model as the theoretical basis for adherence-enhancing interventions. Interventions need to be described in full to allow for the identification of effective components and replication of studies.

  11. A Systematic Review of Marine-Based Species Distribution Models (SDMs with Recommendations for Best Practice

    Directory of Open Access Journals (Sweden)

    Néstor M. Robinson

    2017-12-01

    Full Text Available In the marine environment Species Distribution Models (SDMs have been used in hundreds of papers for predicting the present and future geographic range and environmental niche of species. We have analyzed ways in which SDMs are being applied to marine species in order to recommend best practice in future studies. This systematic review was registered as a protocol on the Open Science Framework: https://osf.io/tngs6/. The literature reviewed (236 papers was published between 1992 and July 2016. The number of papers significantly increased through time (R2 = 0.92, p < 0.05. The studies were predominantly carried out in the Temperate Northern Atlantic (45% followed by studies of global scale (11% and studies in Temperate Australasia (10%. The majority of studies reviewed focused on theoretical ecology (37% including investigations of biological invasions by non-native organisms, conservation planning (19%, and climate change predictions (17%. Most of the studies were published in ecological, multidisciplinary, or biodiversity conservation journals. Most of the studies (94% failed to report the amount of uncertainty derived from data deficiencies and model parameters. Best practice recommendations are proposed here to ensure that novice and advanced SDM users can (a understand the main elements of SDMs, (b reproduce standard methods and analysis, and (c identify potential limitations with their data. We suggest that in the future, studies of marine SDMs should report on key features of the approaches employed, data deficiencies, the selection of the best explanatory model, and the approach taken to validate the SDM results. In addition, based on the literature reviewed, we suggest that future marine SDMs should account for uncertainty levels as part of the modeling process.

  12. Numerical Studies of Thermal Conditions in Cities - Systematic Model Simulations of Idealized Urban Domains

    Science.gov (United States)

    Heene, V.; Buchholz, S.; Kossmann, M.

    2016-12-01

    Numerical studies of thermal conditions in cities based on model simulations of idealized urban domains are carried out to investigate how changes in the characteristics of urban areas influence street level air temperatures. The simulated modifications of the urban characteristics represent possible adaptation measures for heat reduction in cities, which are commonly used in urban planning. Model simulations are performed with the thermodynamic version of the 3-dimensional micro-scale urban climate model MUKLIMO_3. The simulated idealized urban areas are designed in a simplistic way, i. e. defining homogeneous squared cities of one settlement type, without orography and centered in the model domain. To assess the impact of different adaptation measures the characteristics of the urban areas have been systematically modified regarding building height, albedo of building roof and impervious surfaces, fraction of impervious surfaces between buildings, and percentage of green roofs. To assess the impact of green and blue infrastructure in cities, different configurations for parks and lakes have been investigated - e. g. varying size and distribution within the city. The experiments are performed for different combinations of typical German settlement types and surrounding rural types under conditions of a typical summer day in July. The adaptation measures implemented in the experiments show different impacts for different settlement types mainly due to the differences in building density, building height or impervious surface fraction. Parks and lakes implemented as adaptation measure show strong potential to reduce daytime air temperature, with cooling effects on their built-up surroundings. At night lakes generate negative and positive effects on air temperature, depending on water temperature. In general, all adaptation measures implemented in experiments reveal different impacts on day and night air temperature.

  13. Evaluation models and criteria of the quality of hospital websites: a systematic review study.

    Science.gov (United States)

    Jeddi, Fatemeh Rangraz; Gilasi, Hamidreza; Khademi, Sahar

    2017-02-01

    Hospital websites are important tools in establishing communication and exchanging information between patients and staff, and thus should enjoy an acceptable level of quality. The aim of this study was to identify proper models and criteria to evaluate the quality of hospital websites. This research was a systematic review study. The international databases such as Science Direct, Google Scholar, PubMed, Proquest, Ovid, Elsevier, Springer, and EBSCO together with regional database such as Magiran, Scientific Information Database, Persian Journal Citation Report (PJCR) and IranMedex were searched. Suitable keywords including website, evaluation, and quality of website were used. Full text papers related to the research were included. The criteria and sub criteria of the evaluation of website quality were extracted and classified. To evaluate the quality of the websites, various models and criteria were presented. The WEB-Q-IM, Mile, Minerva, Seruni Luci, and Web-Qual models were the designed models. The criteria of accessibility, content and apparent features of the websites, the design procedure, the graphics applied in the website, and the page's attractions have been mentioned in the majority of studies. The criteria of accessibility, content, design method, security, and confidentiality of personal information are the essential criteria in the evaluation of all websites. It is suggested that the ease of use, graphics, attractiveness and other apparent properties of websites are considered as the user-friendliness sub criteria. Further, the criteria of speed and accessibility of the website should be considered as sub criterion of efficiency. When determining the evaluation criteria of the quality of websites, attention to major differences in the specific features of any website is essential.

  14. Scale interactions on diurnal toseasonal timescales and their relevanceto model systematic errors

    Directory of Open Access Journals (Sweden)

    G. Yang

    2003-06-01

    Full Text Available Examples of current research into systematic errors in climate models are used to demonstrate the importance of scale interactions on diurnal,intraseasonal and seasonal timescales for the mean and variability of the tropical climate system. It has enabled some conclusions to be drawn about possible processes that may need to be represented, and some recommendations to be made regarding model improvements. It has been shown that the Maritime Continent heat source is a major driver of the global circulation but yet is poorly represented in GCMs. A new climatology of the diurnal cycle has been used to provide compelling evidence of important land-sea breeze and gravity wave effects, which may play a crucial role in the heat and moisture budget of this key region for the tropical and global circulation. The role of the diurnal cycle has also been emphasized for intraseasonal variability associated with the Madden Julian Oscillation (MJO. It is suggested that the diurnal cycle in Sea Surface Temperature (SST during the suppressed phase of the MJO leads to a triggering of cumulus congestus clouds, which serve to moisten the free troposphere and hence precondition the atmosphere for the next active phase. It has been further shown that coupling between the ocean and atmosphere on intraseasonal timescales leads to a more realistic simulation of the MJO. These results stress the need for models to be able to simulate firstly, the observed tri-modal distribution of convection, and secondly, the coupling between the ocean and atmosphere on diurnal to intraseasonal timescales. It is argued, however, that the current representation of the ocean mixed layer in coupled models is not adequate to represent the complex structure of the observed mixed layer, in particular the formation of salinity barrier layers which can potentially provide much stronger local coupling between the atmosphere and ocean on diurnal to intraseasonal timescales.

  15. Tissue Engineering in Animal Models for Urinary Diversion: A Systematic Review

    Science.gov (United States)

    Sloff, Marije; de Vries, Rob; Geutjes, Paul; IntHout, Joanna; Ritskes-Hoitinga, Merel

    2014-01-01

    Tissue engineering and regenerative medicine (TERM) approaches may provide alternatives for gastrointestinal tissue in urinary diversion. To continue to clinically translatable studies, TERM alternatives need to be evaluated in (large) controlled and standardized animal studies. Here, we investigated all evidence for the efficacy of tissue engineered constructs in animal models for urinary diversion. Studies investigating this subject were identified through a systematic search of three different databases (PubMed, Embase and Web of Science). From each study, animal characteristics, study characteristics and experimental outcomes for meta-analyses were tabulated. Furthermore, the reporting of items vital for study replication was assessed. The retrieved studies (8 in total) showed extreme heterogeneity in study design, including animal models, biomaterials and type of urinary diversion. All studies were feasibility studies, indicating the novelty of this field. None of the studies included appropriate control groups, i.e. a comparison with the classical treatment using GI tissue. The meta-analysis showed a trend towards successful experimentation in larger animals although no specific animal species could be identified as the most suitable model. Larger animals appear to allow a better translation to the human situation, with respect to anatomy and surgical approaches. It was unclear whether the use of cells benefits the formation of a neo urinary conduit. The reporting of the methodology and data according to standardized guidelines was insufficient and should be improved to increase the value of such publications. In conclusion, animal models in the field of TERM for urinary diversion have probably been chosen for reasons other than their predictive value. Controlled and comparative long term animal studies, with adequate methodological reporting are needed to proceed to clinical translatable studies. This will aid in good quality research with the reduction in

  16. Parameters for the mathematical modelling of Clostridium difficile acquisition and transmission: a systematic review.

    Directory of Open Access Journals (Sweden)

    Eroboghene H Otete

    Full Text Available INTRODUCTION: Mathematical modelling of Clostridium difficile infection dynamics could contribute to the optimisation of strategies for its prevention and control. The objective of this systematic review was to summarise the available literature specifically identifying the quantitative parameters required for a compartmental mathematical model of Clostridium difficile transmission. METHODS: Six electronic healthcare databases were searched and all screening, data extraction and study quality assessments were undertaken in duplicate. Results were synthesised using a narrative approach. RESULTS: Fifty-four studies met the inclusion criteria. Reproduction numbers for hospital based epidemics were described in two studies with a range from 0.55 to 7. Two studies provided consistent data on incubation periods. For 62% of cases, symptoms occurred in less than 4 weeks (3-28 days after infection. Evidence on contact patterns was identified in four studies but with limited data reported for populating a mathematical model. Two studies, including one without clinically apparent donor-recipient pairs, provided information on serial intervals for household or ward contacts, showing transmission intervals of <1 week in ward based contacts compared to up to 2 months for household contacts. Eight studies reported recovery rates of between 75%-100% for patients who had been treated with either metronidazole or vancomycin. Forty-nine studies gave recurrence rates of between 3% and 49% but were limited by varying definitions of recurrence. No study was found which specifically reported force of infection or net reproduction numbers. CONCLUSIONS: There is currently scant literature overtly citing estimates of the parameters required to inform the quantitative modelling of Clostridium difficile transmission. Further high quality studies to investigate transmission parameters are required, including through review of published epidemiological studies where these

  17. Primary care models for treating opioid use disorders: What actually works? A systematic review.

    Directory of Open Access Journals (Sweden)

    Pooja Lagisetty

    Full Text Available Primary care-based models for Medication-Assisted Treatment (MAT have been shown to reduce mortality for Opioid Use Disorder (OUD and have equivalent efficacy to MAT in specialty substance treatment facilities.The objective of this study is to systematically analyze current evidence-based, primary care OUD MAT interventions and identify program structures and processes associated with improved patient outcomes in order to guide future policy and implementation in primary care settings.PubMed, EMBASE, CINAHL, and PsychInfo.We included randomized controlled or quasi experimental trials and observational studies evaluating OUD treatment in primary care settings treating adult patient populations and assessed structural domains using an established systems engineering framework.We included 35 interventions (10 RCTs and 25 quasi-experimental interventions that all tested MAT, buprenorphine or methadone, in primary care settings across 8 countries. Most included interventions used joint multi-disciplinary (specialty addiction services combined with primary care and coordinated care by physician and non-physician provider delivery models to provide MAT. Despite large variability in reported patient outcomes, processes, and tasks/tools used, similar key design factors arose among successful programs including integrated clinical teams with support staff who were often advanced practice clinicians (nurses and pharmacists as clinical care managers, incorporating patient "agreements," and using home inductions to make treatment more convenient for patients and providers.The findings suggest that multidisciplinary and coordinated care delivery models are an effective strategy to implement OUD treatment and increase MAT access in primary care, but research directly comparing specific structures and processes of care models is still needed.

  18. Tissue engineering in animal models for urinary diversion: a systematic review.

    Directory of Open Access Journals (Sweden)

    Marije Sloff

    Full Text Available Tissue engineering and regenerative medicine (TERM approaches may provide alternatives for gastrointestinal tissue in urinary diversion. To continue to clinically translatable studies, TERM alternatives need to be evaluated in (large controlled and standardized animal studies. Here, we investigated all evidence for the efficacy of tissue engineered constructs in animal models for urinary diversion. Studies investigating this subject were identified through a systematic search of three different databases (PubMed, Embase and Web of Science. From each study, animal characteristics, study characteristics and experimental outcomes for meta-analyses were tabulated. Furthermore, the reporting of items vital for study replication was assessed. The retrieved studies (8 in total showed extreme heterogeneity in study design, including animal models, biomaterials and type of urinary diversion. All studies were feasibility studies, indicating the novelty of this field. None of the studies included appropriate control groups, i.e. a comparison with the classical treatment using GI tissue. The meta-analysis showed a trend towards successful experimentation in larger animals although no specific animal species could be identified as the most suitable model. Larger animals appear to allow a better translation to the human situation, with respect to anatomy and surgical approaches. It was unclear whether the use of cells benefits the formation of a neo urinary conduit. The reporting of the methodology and data according to standardized guidelines was insufficient and should be improved to increase the value of such publications. In conclusion, animal models in the field of TERM for urinary diversion have probably been chosen for reasons other than their predictive value. Controlled and comparative long term animal studies, with adequate methodological reporting are needed to proceed to clinical translatable studies. This will aid in good quality research with

  19. Random variables in forest policy: A systematic sensitivity analysis using CGE models

    International Nuclear Information System (INIS)

    Alavalapati, J.R.R.

    1999-01-01

    Computable general equilibrium (CGE) models are extensively used to simulate economic impacts of forest policies. Parameter values used in these models often play a central role in their outcome. Since econometric studies and best guesses are the main sources of these parameters, some randomness exists about the 'true' values of these parameters. Failure to incorporate this randomness into these models may limit the degree of confidence in the validity of the results. In this study, we conduct a systematic sensitivity analysis (SSA) to assess the economic impacts of: 1) a 1 % increase in tax on Canadian lumber and wood products exports to the United States (US), and 2) a 1% decrease in technical change in the lumber and wood products and pulp and paper sectors of the US and Canada. We achieve this task by using an aggregated version of global trade model developed by Hertel (1997) and the automated SSA procedure developed by Arndt and Pearson (1996). The estimated means and standard deviations suggest that certain impacts are more likely than others. For example, an increase in export tax is likely to cause a decrease in Canadian income, while an increase in US income is unlikely. On the other hand, a decrease in US welfare is likely, while an increase in Canadian welfare is unlikely, in response to an increase in tax. It is likely that income and welfare both fall in Canada and the US in response to a decrease in the technical change in lumber and wood products and pulp and paper sectors 21 refs, 1 fig, 5 tabs

  20. Are the impacts of land use on warming underestimated in climate policy?

    Science.gov (United States)

    Mahowald, Natalie M.; Ward, Daniel S.; Doney, Scott C.; Hess, Peter G.; Randerson, James T.

    2017-09-01

    While carbon dioxide emissions from energy use must be the primary target of climate change mitigation efforts, land use and land cover change (LULCC) also represent an important source of climate forcing. In this study we compute time series of global surface temperature change separately for LULCC and non-LULCC sources (primarily fossil fuel burning), and show that because of the extra warming associated with the co-emission of methane and nitrous oxide with LULCC carbon dioxide emissions, and a co-emission of cooling aerosols with non-LULCC emissions of carbon dioxide, the linear relationship between cumulative carbon dioxide emissions and temperature has a two-fold higher slope for LULCC than for non-LULCC activities. Moreover, projections used in the Intergovernmental Panel on Climate Change (IPCC) for the rate of tropical land conversion in the future are relatively low compared to contemporary observations, suggesting that the future projections of land conversion used in the IPCC may underestimate potential impacts of LULCC. By including a ‘business as usual’ future LULCC scenario for tropical deforestation, we find that even if all non-LULCC emissions are switched off in 2015, it is likely that 1.5 °C of warming relative to the preindustrial era will occur by 2100. Thus, policies to reduce LULCC emissions must remain a high priority if we are to achieve the low to medium temperature change targets proposed as a part of the Paris Agreement. Future studies using integrated assessment models and other climate simulations should include more realistic deforestation rates and the integration of policy that would reduce LULCC emissions.

  1. Dual-energy X-ray absorptiometry underestimates in vivo lumbar spine bone mineral density in overweight rats.

    Science.gov (United States)

    Cherif, Rim; Vico, Laurence; Laroche, Norbert; Sakly, Mohsen; Attia, Nebil; Lavet, Cedric

    2018-01-01

    Dual-energy X-ray absorptiometry (DXA) is currently the most widely used technique for measuring areal bone mineral density (BMD). However, several studies have shown inaccuracy, with either overestimation or underestimation of DXA BMD measurements in the case of overweight or obese individuals. We have designed an overweight rat model based on junk food to compare the effect of obesity on in vivo and ex vivo BMD and bone mineral content measurements. Thirty-eight 6-month old male rats were given a chow diet (n = 13) or a high fat and sucrose diet (n = 25), with the calorie amount being kept the same in the two groups, for 19 weeks. L1 BMD, L1 bone mineral content, amount of abdominal fat, and amount of abdominal lean were obtained from in vivo DXA scan. Ex vivo L1 BMD was also measured. A difference between in vivo and ex vivo DXA BMD measurements (P body weight, perirenal fat, abdominal fat, and abdominal lean. Multiple linear regression analysis shows that body weight, abdominal fat, and abdominal lean were independently related to ex vivo BMD. DXA underestimated lumbar in vivo BMD in overweight rats, and this measurement error is related to body weight and abdominal fat. Therefore, caution must be used when one is interpreting BMD among overweight and obese individuals.

  2. A systematic review of land use regression models for volatile organic compounds

    Science.gov (United States)

    Amini, Heresh; Yunesian, Masud; Hosseini, Vahid; Schindler, Christian; Henderson, Sarah B.; Künzli, Nino

    2017-12-01

    Various aspects of land use regression (LUR) models for volatile organic compounds (VOCs) were systematically reviewed. Sixteen studies were identified published between 2002 and 2017. Of these, six were conducted in Canada, five in the USA, two in Spain, and one each in Germany, Italy, and Iran. They were developed for 14 different individual VOCs or groupings: benzene; toluene; ethylbenzene; m-xylene; p-xylene; (m/p)-xylene; o-xylene; total BTEX; 1,3-butadiene; formaldehyde; n-hexane; total hydro carbons; styrene; and acrolein. The models were based on measurements ranging from 22 sites in El Paso (USA) to 179 sites in Tehran (Iran). Only four studies in Rome (Italy), Sabadell (Spain), Tehran, and Windsor (Canada) met the Cocheo's criterion of having at least one passive sampler per 3.4 km2 of study area. The range of R2 values across all models was from 0.26 for 1,3-butadiene in Dallas (USA) to 0.93 for benzene in El Paso. The average R2 values among two or more studies of the same VOCs were as follows: benzene (0.70); toluene (0.60); ethylbenzene (0.66); (m/p)-xylene (0.65); o-xylene (0.61); total BTEX (0.66); 1,3-butadiene (0.46); and formaldehyde (0.56). The common spatial predictors of studied VOC concentrations were dominated by traffic-related variables, but they also included proximity to ports in the USA, number of chimneys in Canada, altitude in Spain, northern latitudes in Italy, and proximity to sewage treatment plants and to gas filling stores in Iran. For the traffic-related variables, the review suggests that large buffers, up to 5,000 m, should be considered in large cities. Although most studies reported logical directions of association for predictors, some reported inconsistent results. Some studies included log-transformed predictors while others divided one variable by another. Only six studies provided the p-values of predictors. Future work may incorporate chemistry-transport models, satellite observations, meteorological variables

  3. Prediction models for the mortality risk in chronic dialysis patients: a systematic review and independent external validation study.

    Science.gov (United States)

    Ramspek, Chava L; Voskamp, Pauline Wm; van Ittersum, Frans J; Krediet, Raymond T; Dekker, Friedo W; van Diepen, Merel

    2017-01-01

    In medicine, many more prediction models have been developed than are implemented or used in clinical practice. These models cannot be recommended for clinical use before external validity is established. Though various models to predict mortality in dialysis patients have been published, very few have been validated and none are used in routine clinical practice. The aim of the current study was to identify existing models for predicting mortality in dialysis patients through a review and subsequently to externally validate these models in the same large independent patient cohort, in order to assess and compare their predictive capacities. A systematic review was performed following the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. To account for missing data, multiple imputation was performed. The original prediction formulae were extracted from selected studies. The probability of death per model was calculated for each individual within the Netherlands Cooperative Study on the Adequacy of Dialysis (NECOSAD). The predictive performance of the models was assessed based on their discrimination and calibration. In total, 16 articles were included in the systematic review. External validation was performed in 1,943 dialysis patients from NECOSAD for a total of seven models. The models performed moderately to well in terms of discrimination, with C -statistics ranging from 0.710 (interquartile range 0.708-0.711) to 0.752 (interquartile range 0.750-0.753) for a time frame of 1 year. According to the calibration, most models overestimated the probability of death. Overall, the performance of the models was poorer in the external validation than in the original population, affirming the importance of external validation. Floege et al's models showed the highest predictive performance. The present study is a step forward in the use of a prediction model as a useful tool for nephrologists, using evidence-based medicine that

  4. Service-Oriented Enterprise Architecture (SoEA) Adoption and Maturity Measurement Model: A Systematic Literature Review

    OpenAIRE

    Nur Azaliah Abu Bakar; Harihodin Selamat; Mohd Nazri Kama

    2013-01-01

    This article provides a systematic review of existing research related to the Service-oriented Enterprise Architecture (SoEA) adoption and maturity measurement model. The review’s main goals are to support research; to facilitate other researchers’ search for relevant studies; and to propose areas for future studies within this area. In addition, this article provides useful information on SoEA adoption issues and its related maturity model, based on research-based knowledge. The review resul...

  5. Factors associated with adoption of health information technology: a conceptual model based on a systematic review.

    Science.gov (United States)

    Kruse, Clemens Scott; DeShazo, Jonathan; Kim, Forest; Fulton, Lawrence

    2014-05-23

    The Health Information Technology for Economic and Clinical Health Act (HITECH) allocated $19.2 billion to incentivize adoption of the electronic health record (EHR). Since 2009, Meaningful Use Criteria have dominated information technology (IT) strategy. Health care organizations have struggled to meet expectations and avoid penalties to reimbursements from the Center for Medicare and Medicaid Services (CMS). Organizational theories attempt to explain factors that influence organizational change, and many theories address changes in organizational strategy. However, due to the complexities of the health care industry, existing organizational theories fall short of demonstrating association with significant health care IT implementations. There is no organizational theory for health care that identifies, groups, and analyzes both internal and external factors of influence for large health care IT implementations like adoption of the EHR. The purpose of this systematic review is to identify a full-spectrum of both internal organizational and external environmental factors associated with the adoption of health information technology (HIT), specifically the EHR. The result is a conceptual model that is commensurate with the complexity of with the health care sector. We performed a systematic literature search in PubMed (restricted to English), EBSCO Host, and Google Scholar for both empirical studies and theory-based writing from 1993-2013 that demonstrated association between influential factors and three modes of HIT: EHR, electronic medical record (EMR), and computerized provider order entry (CPOE). We also looked at published books on organizational theories. We made notes and noted trends on adoption factors. These factors were grouped as adoption factors associated with various versions of EHR adoption. The resulting conceptual model summarizes the diversity of independent variables (IVs) and dependent variables (DVs) used in articles, editorials, books, as

  6. The psychoneuroimmunological effects of music: a systematic review and a new model.

    Science.gov (United States)

    Fancourt, Daisy; Ockelford, Adam; Belai, Abi

    2014-02-01

    There has been a growing interest over the past decade into the health benefits of music, in particular examining its psychological and neurological effects. Yet this is the first attempt to systematically review publications on the psychoneuroimmunology of music. Of the selected sixty-three studies published over the past 22 years, a range of effects of music on neurotransmitters, hormones, cytokines, lymphocytes, vital signs and immunoglobulins as well as psychological assessments are cataloged. Research so far points to the pivotal role of stress pathways in linking music to an immune response. However, several challenges to this research are noted: (1) there is very little discussion on the possible mechanisms by which music is achieving its neurological and immunological impact; (2) the studies tend to examine biomarkers in isolation, without taking into consideration the interaction of the biomarkers in question with other physiological or metabolic activities of the body, leading to an unclear understanding of the impact that music may be having; (3) terms are not being defined clearly enough, such as distinctions not being made between different kinds of stress and 'music' being used to encompass a broad spectrum of activities without determining which aspects of musical engagement are responsible for alterations in biomarkers. In light of this, a new model is presented which provides a framework for developing a taxonomy of musical and stress-related variables in research design, and tracing the broad pathways that are involved in its influence on the body. Copyright © 2013 Elsevier Inc. All rights reserved.

  7. Enamel matrix derivative for replanted teeth in animal models: a systematic review and meta-analysis

    Directory of Open Access Journals (Sweden)

    Sahng G. Kim

    2013-11-01

    Full Text Available Objectives To investigate the effect of enamel matrix derivative (EMD on periodontal healing of replanted teeth in animal models. Materials and Methods The authors searched MEDLINE, PubMed, EMBASE, Cochrane Library, Web of Knowledge and Scopus for articles published up to Oct 2012. Animal studies in which EMD was applied in transplanted or replanted teeth with adequate controls and histological data were considered. Normal periodontal healing or root resorption determined by histology after EMD was applied in replanted teeth with adequate controls was used as outcome measures. The following search strategy was used: ('Emdogain' OR 'enamel matrix proteins' OR 'enamel matrix derivative' AND ('avulsion' OR 'transplantion' OR 'autotransplantation' OR 'replantation'. Results Six animal studies were included in the final review. There was great heterogeneity in study design among included studies. Two studies with similar study designs were identified and analyzed by a meta-analysis. The pooled estimates showed a significantly higher normal healing and surface resorption and significantly less inflammatory and replacement resorption in EMD-treated groups compared with non-EMD-treated groups. Conclusions With the limitations of this systematic review, the use of EMD led to greater normal periodontal healing and surface root resorption and less inflammatory and replacement root resorption in the presence of periodontal ligaments. However, no definite conclusion could be drawn with regard to the effect of EMD on periodontal healing and root resorption when no periodontal ligaments exist.

  8. Genetics of borderline personality disorder: systematic review and proposal of an integrative model.

    Science.gov (United States)

    Amad, Ali; Ramoz, Nicolas; Thomas, Pierre; Jardri, Renaud; Gorwood, Philip

    2014-03-01

    Borderline personality disorder (BPD) is one of the most common mental disorders and is characterized by a pervasive pattern of emotional lability, impulsivity, interpersonal difficulties, identity disturbances, and disturbed cognition. Here, we performed a systematic review of the literature concerning the genetics of BPD, including familial and twin studies, association studies, and gene-environment interaction studies. Moreover, meta-analyses were performed when at least two case-control studies testing the same polymorphism were available. For each gene variant, a pooled odds ratio (OR) was calculated using fixed or random effects models. Familial and twin studies largely support the potential role of a genetic vulnerability at the root of BPD, with an estimated heritability of approximately 40%. Moreover, there is evidence for both gene-environment interactions and correlations. However, association studies for BPD are sparse, making it difficult to draw clear conclusions. According to our meta-analysis, no significant associations were found for the serotonin transporter gene, the tryptophan hydroxylase 1 gene, or the serotonin 1B receptor gene. We hypothesize that such a discrepancy (negative association studies but high heritability of the disorder) could be understandable through a paradigm shift, in which "plasticity" genes (rather than "vulnerability" genes) would be involved. Such a framework postulates a balance between positive and negative events, which interact with plasticity genes in the genesis of BPD. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Identification of cutoff points for Homeostatic Model Assessment for Insulin Resistance index in adolescents: systematic review

    Science.gov (United States)

    de Andrade, Maria Izabel Siqueira; Oliveira, Juliana Souza; Leal, Vanessa Sá; da Lima, Niedja Maria Silva; Costa, Emília Chagas; de Aquino, Nathalia Barbosa; de Lira, Pedro Israel Cabral

    2016-01-01

    Abstract Objective: To identify cutoff points of the Homeostatic Model Assessment for Insulin Resistance (HOMA-IR) index established for adolescents and discuss their applicability for the diagnosis of insulin resistance in Brazilian adolescents. Data source: A systematic review was performed in the PubMed, Lilacs and SciELO databases, using the following descriptors: "adolescents", "insulin resistance" and "Receiver Operating Characteristics Curve". Original articles carried out with adolescents published between 2005 and 2015 in Portuguese, English or Spanish languages, which included the statistical analysis using Receiver Operating Characteristics Curve to determine the index cutoff (HOMA-IR) were included. Data synthesis: A total of 184 articles were identified and after the study phases were applied, seven articles were selected for the review. All selected studies established their cutoffs using a Receiver Operating Characteristics Curve, with the lowest observed cutoff of 1.65 for girls and 1.95 for boys and the highest of 3.82 for girls and 5.22 for boys. Of the studies analyzed, one proposed external validity, recommending the use of the HOMA-IR cutoff>2.5 for both genders. Conclusions: The HOMA-IR index constitutes a reliable method for the detection of insulin resistance in adolescents, as long as it uses cutoffs that are more adequate for the reality of the study population, allowing early diagnosis of insulin resistance and enabling multidisciplinary interventions aiming at health promotion of this population. PMID:26559605

  10. A systematic model to compare nurses' optimal and actual competencies in the clinical setting.

    Science.gov (United States)

    Meretoja, Riitta; Koponen, Leena

    2012-02-01

    This paper is a report of a study to develop a model to compare nurses' optimal and actual competencies in the clinical setting.   Although future challenge is to focus the developmental and educational targets in health care, limited information is available on methods for how to predict optimal competencies. A multidisciplinary group of 24 experts on perioperative care were recruited to this study. They anticipated the effects of future challenges on perioperative care and specified the level of optimal competencies by using the Nurse Competence Scale before and after group discussions. The expert group consensus discussions were held to achieve the highest possible agreement on the overall level of optimal competencies. Registered Nurses (n = 87) and their nurse managers from five different units conducted assessments of the actual level of nurse competence with the Nurse Competence Scale instrument. Data were collected in 2006-2007. Group consensus discussions solidified experts' anticipations about the optimal competence level. This optimal competence level was significantly higher than the nurses' self-reported actual or nurse managers' assessed level of actual competence. The study revealed some competence items that were seen as key challenges for future education of professional nursing practice. It is important that the multidisciplinary experts in a particular care context develop a share understanding of the future competency requirements of patient care. Combining optimal competence profiles to systematic competence assessments contribute to targeted continual learning and educational interventions. © 2011 Blackwell Publishing Ltd.

  11. Implementation of the Crisis Resolution Team model in adult mental health settings: a systematic review.

    Science.gov (United States)

    Wheeler, Claire; Lloyd-Evans, Brynmor; Churchard, Alasdair; Fitzgerald, Caroline; Fullarton, Kate; Mosse, Liberty; Paterson, Bethan; Zugaro, Clementina Galli; Johnson, Sonia

    2015-04-08

    Crisis Resolution Teams (CRTs) aim to offer an alternative to hospital admission during mental health crises, providing rapid assessment, home treatment, and facilitation of early discharge from hospital. CRTs were implemented nationally in England following the NHS Plan of 2000. Single centre studies suggest CRTs can reduce hospital admissions and increase service users' satisfaction: however, there is also evidence that model implementation and outcomes vary considerably. Evidence on crucial characteristics of effective CRTs is needed to allow team functioning to be optimised. This review aims to establish what evidence, if any, is available regarding the characteristics of effective and acceptable CRTs. A systematic review was conducted. MEDLINE, Embase, PsycINFO, CINAHL and Web of Science were searched to November 2013. A further web-based search was conducted for government and expert guidelines on CRTs. We analysed studies separately as: comparing CRTs to Treatment as Usual; comparing two or more CRT models; national or regional surveys of CRT services; qualitative studies of stakeholders' views regarding best practice in CRTs; and guidelines from government and expert organisations regarding CRT service delivery. Quality assessment and narrative synthesis were conducted. Statistical meta-analysis was not feasible due to the variety of design of retrieved studies. Sixty-nine studies were included. Studies varied in quality and in the composition and activities of the clinical services studied. Quantitative studies suggested that longer opening hours and the presence of a psychiatrist in the team may increase CRTs' ability to prevent hospital admissions. Stakeholders emphasised communication and integration with other local mental health services; provision of treatment at home; and limiting the number of different staff members visiting a service user. Existing guidelines prioritised 24-hour, seven-day-a-week CRT service provision (including psychiatrist and

  12. Patient neglect in healthcare institutions: a systematic review and conceptual model

    Science.gov (United States)

    2013-01-01

    Background Patient neglect is an issue of increasing public concern in Europe and North America, yet remains poorly understood. This is the first systematic review on the nature, frequency and causes of patient neglect as distinct from patient safety topics such as medical error. Method The Pubmed, Science Direct, and Medline databases were searched in order to identify research studies investigating patient neglect. Ten articles and four government reports met the inclusion criteria of reporting primary data on the occurrence or causes of patient neglect. Qualitative and quantitative data extraction investigated (1) the definition of patient neglect, (2) the forms of behaviour associated with neglect, (3) the reported frequency of neglect, and (4) the causes of neglect. Results Patient neglect is found to have two aspects. First, procedure neglect, which refers to failures of healthcare staff to achieve objective standards of care. Second, caring neglect, which refers to behaviours that lead patients and observers to believe that staff have uncaring attitudes. The perceived frequency of neglectful behaviour varies by observer. Patients and their family members are more likely to report neglect than healthcare staff, and nurses are more likely to report on the neglectful behaviours of other nurses than on their own behaviour. The causes of patient neglect frequently relate to organisational factors (e.g. high workloads that constrain the behaviours of healthcare staff, burnout), and the relationship between carers and patients. Conclusion A social psychology-based conceptual model is developed to explain the occurrence and nature of patient neglect. This model will facilitate investigations of i) differences between patients and healthcare staff in how they perceive neglect, ii) the association with patient neglect and health outcomes, iii) the relative importance of system and organisational factors in causing neglect, and iv) the design of interventions and

  13. Systematic Review of Health Economic Impact Evaluations of Risk Prediction Models: Stop Developing, Start Evaluating.

    Science.gov (United States)

    van Giessen, Anoukh; Peters, Jaime; Wilcher, Britni; Hyde, Chris; Moons, Carl; de Wit, Ardine; Koffijberg, Erik

    2017-04-01

    Although health economic evaluations (HEEs) are increasingly common for therapeutic interventions, they appear to be rare for the use of risk prediction models (PMs). To evaluate the current state of HEEs of PMs by performing a comprehensive systematic review. Four databases were searched for HEEs of PM-based strategies. Two reviewers independently selected eligible articles. A checklist was compiled to score items focusing on general characteristics of HEEs of PMs, model characteristics and quality of HEEs, evidence on PMs typically used in the HEEs, and the specific challenges in performing HEEs of PMs. After screening 791 abstracts, 171 full texts, and reference checking, 40 eligible HEEs evaluating 60 PMs were identified. In these HEEs, PM strategies were compared with current practice (n = 32; 80%), to other stratification methods for patient management (n = 19; 48%), to an extended PM (n = 9; 23%), or to alternative PMs (n = 5; 13%). The PMs guided decisions on treatment (n = 42; 70%), further testing (n = 18; 30%), or treatment prioritization (n = 4; 7%). For 36 (60%) PMs, only a single decision threshold was evaluated. Costs of risk prediction were ignored for 28 (46%) PMs. Uncertainty in outcomes was assessed using probabilistic sensitivity analyses in 22 (55%) HEEs. Despite the huge number of PMs in the medical literature, HEE of PMs remains rare. In addition, we observed great variety in their quality and methodology, which may complicate interpretation of HEE results and implementation of PMs in practice. Guidance on HEE of PMs could encourage and standardize their application and enhance methodological quality, thereby improving adequate use of PM strategies. Copyright © 2017 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

  14. Molecular structure based property modeling: Development/ improvement of property models through a systematic property-data-model analysis

    DEFF Research Database (Denmark)

    Hukkerikar, Amol Shivajirao; Sarup, Bent; Sin, Gürkan

    2013-01-01

    The objective of this work is to develop a method for performing property-data-model analysis so that efficient use of knowledge of properties could be made in the development/improvement of property prediction models. The method includes: (i) analysis of property data and its consistency check; ......, a method for selecting a minimum data-set for the parameter regression is also discussed for the cases where it is preferred to retain some data-points from the total data-set to test the reliability of predictions for validation purposes.......; (ii) selection of the most appropriate form of the property model; (iii) selection of the data-set for performing parameter regression and uncertainty analysis; and (iv) analysis of model prediction errors to take necessary corrective steps to improve the accuracy and the reliability of property...

  15. Observational studies using propensity score analysis underestimated the effect sizes in critical care medicine.

    Science.gov (United States)

    Zhang, Zhongheng; Ni, Hongying; Xu, Xiao

    2014-08-01

    Propensity score (PS) analysis has been increasingly used in critical care medicine; however, its validation has not been systematically investigated. The present study aimed to compare effect sizes in PS-based observational studies vs. randomized controlled trials (RCTs) (or meta-analysis of RCTs). Critical care observational studies using PS were systematically searched in PubMed from inception to April 2013. Identified PS-based studies were matched to one or more RCTs in terms of population, intervention, comparison, and outcome. The effect sizes of experimental treatments were compared for PS-based studies vs. RCTs (or meta-analysis of RCTs) with sign test. Furthermore, ratio of odds ratio (ROR) was calculated from the interaction term of treatment × study type in a logistic regression model. A ROR analysis of RCTs) were more likely to report beneficial effect for the experimental treatment than PS-based studies. The result remained unchanged in sensitivity analysis and meta-regression. In critical care literature, PS-based observational study is likely to report less beneficial effect of experimental treatment compared with RCTs (or meta-analysis of RCTs). Copyright © 2014 Elsevier Inc. All rights reserved.

  16. An evaluation of a model for the systematic documentation of hospital based health promotion activities: results from a multicentre study

    DEFF Research Database (Denmark)

    Tønnesen, Hanne; Christensen, Mette E; Groene, Oliver

    2007-01-01

    and in patient administrative systems have been sparse. Therefore, the activities are mostly invisible in the registers of hospital services as well as in budgets and balances.A simple model has been described to structure the registration of the HP procedures performed by the clinical staff. The model consists...... of two parts; first part includes motivational counselling (7 codes) and the second part comprehends intervention, rehabilitation and after treatment (8 codes).The objective was to evaluate in an international study the usefulness, applicability and sufficiency of a simple model for the systematic...

  17. A systematic methodology to extend the applicability of a bioconversion model for the simulation of various co-digestion scenarios

    DEFF Research Database (Denmark)

    Kovalovszki, Adam; Alvarado-Morales, Merlin; Fotidis, Ioannis

    2017-01-01

    was extended to various co-digestion scenarios. More specifically, the application of the step-by-step methodology led to the estimation of a general and reduced set of parameters, for the simulation of scenarios where either manure or wastewater were co-digested with different organic substrates. Validation......Detailed simulation of anaerobic digestion (AD) requires complex mathematical models and the optimization of numerous model parameters. By performing a systematic methodology and identifying parameters with the highest impact on process variables in a well-established AD model, its applicability...

  18. Neural systems language: a formal modeling language for the systematic description, unambiguous communication, and automated digital curation of neural connectivity.

    Science.gov (United States)

    Brown, Ramsay A; Swanson, Larry W

    2013-09-01

    Systematic description and the unambiguous communication of findings and models remain among the unresolved fundamental challenges in systems neuroscience. No common descriptive frameworks exist to describe systematically the connective architecture of the nervous system, even at the grossest level of observation. Furthermore, the accelerating volume of novel data generated on neural connectivity outpaces the rate at which this data is curated into neuroinformatics databases to synthesize digitally systems-level insights from disjointed reports and observations. To help address these challenges, we propose the Neural Systems Language (NSyL). NSyL is a modeling language to be used by investigators to encode and communicate systematically reports of neural connectivity from neuroanatomy and brain imaging. NSyL engenders systematic description and communication of connectivity irrespective of the animal taxon described, experimental or observational technique implemented, or nomenclature referenced. As a language, NSyL is internally consistent, concise, and comprehensible to both humans and computers. NSyL is a promising development for systematizing the representation of neural architecture, effectively managing the increasing volume of data on neural connectivity and streamlining systems neuroscience research. Here we present similar precedent systems, how NSyL extends existing frameworks, and the reasoning behind NSyL's development. We explore NSyL's potential for balancing robustness and consistency in representation by encoding previously reported assertions of connectivity from the literature as examples. Finally, we propose and discuss the implications of a framework for how NSyL will be digitally implemented in the future to streamline curation of experimental results and bridge the gaps among anatomists, imagers, and neuroinformatics databases. Copyright © 2013 Wiley Periodicals, Inc.

  19. Dual-use tools and systematics-aware analysis workflows in the ATLAS Run-2 analysis model

    CERN Document Server

    FARRELL, Steven; The ATLAS collaboration; Calafiura, Paolo; Delsart, Pierre-Antoine; Elsing, Markus; Koeneke, Karsten; Krasznahorkay, Attila; Krumnack, Nils; Lancon, Eric; Lavrijsen, Wim; Laycock, Paul; Lei, Xiaowen; Strandberg, Sara Kristina; Verkerke, Wouter; Vivarelli, Iacopo; Woudstra, Martin

    2015-01-01

    The ATLAS analysis model has been overhauled for the upcoming run of data collection in 2015 at 13 TeV. One key component of this upgrade was the Event Data Model (EDM), which now allows for greater flexibility in the choice of analysis software framework and provides powerful new features that can be exploited by analysis software tools. A second key component of the upgrade is the introduction of a dual-use tool technology, which provides abstract interfaces for analysis software tools to run in either the Athena framework or a ROOT-based framework. The tool interfaces, including a new interface for handling systematic uncertainties, have been standardized for the development of improved analysis workflows and consolidation of high-level analysis tools. This paper will cover the details of the dual-use tool functionality, the systematics interface, and how these features fit into a centrally supported analysis environment.

  20. Dual-use tools and systematics-aware analysis workflows in the ATLAS Run-II analysis model

    CERN Document Server

    FARRELL, Steven; The ATLAS collaboration

    2015-01-01

    The ATLAS analysis model has been overhauled for the upcoming run of data collection in 2015 at 13 TeV. One key component of this upgrade was the Event Data Model (EDM), which now allows for greater flexibility in the choice of analysis software framework and provides powerful new features that can be exploited by analysis software tools. A second key component of the upgrade is the introduction of a dual-use tool technology, which provides abstract interfaces for analysis software tools to run in either the Athena framework or a ROOT-based framework. The tool interfaces, including a new interface for handling systematic uncertainties, have been standardized for the development of improved analysis workflows and consolidation of high-level analysis tools. This presentation will cover the details of the dual-use tool functionality, the systematics interface, and how these features fit into a centrally supported analysis environment.

  1. Quantification of Underestimation of Physical Activity During Cycling to School When Using Accelerometry

    DEFF Research Database (Denmark)

    Tarp, Jakob; Andersen, Lars B; Østergaard, Lars

    2015-01-01

    Background: Cycling to and from school is an important source of physical activity (PA) in youth but it is not captured by the dominant objective method to quantify PA. The aim of this study was to quantify the underestimation of objectively assessed PA caused by cycling when using accelerometry....... Methods: Participants were 20 children aged 11-14 years from a randomized controlled trial performed in 2011. Physical activity was assessed by accelerometry with the addition of heart rate monitoring during cycling to school. Global positioning system (GPS) was used to identify periods of cycling...... to school. Results: Mean (95% CI) minutes of moderate-to-vigorous physical activity (MVPA) during round-trip commutes was 10.8 (7.1 - 16.6). Each kilometre of cycling meant an underestimation of 9314 (95%CI: 7719 - 11238) counts and 2.7 (95%CI: 2.1 - 3.5) minutes of MVPA. Adjusting for cycling to school...

  2. A Systematic Approach for Model-Based Aircraft Engine Performance Estimation

    Science.gov (United States)

    Simon, Donald L.; Garg, Sanjay

    2010-01-01

    A requirement for effective aircraft engine performance estimation is the ability to account for engine degradation, generally described in terms of unmeasurable health parameters such as efficiencies and flow capacities related to each major engine module. This paper presents a linear point design methodology for minimizing the degradation-induced error in model-based aircraft engine performance estimation applications. The technique specifically focuses on the underdetermined estimation problem, where there are more unknown health parameters than available sensor measurements. A condition for Kalman filter-based estimation is that the number of health parameters estimated cannot exceed the number of sensed measurements. In this paper, the estimated health parameter vector will be replaced by a reduced order tuner vector whose dimension is equivalent to the sensed measurement vector. The reduced order tuner vector is systematically selected to minimize the theoretical mean squared estimation error of a maximum a posteriori estimator formulation. This paper derives theoretical estimation errors at steady-state operating conditions, and presents the tuner selection routine applied to minimize these values. Results from the application of the technique to an aircraft engine simulation are presented and compared to the estimation accuracy achieved through conventional maximum a posteriori and Kalman filter estimation approaches. Maximum a posteriori estimation results demonstrate that reduced order tuning parameter vectors can be found that approximate the accuracy of estimating all health parameters directly. Kalman filter estimation results based on the same reduced order tuning parameter vectors demonstrate that significantly improved estimation accuracy can be achieved over the conventional approach of selecting a subset of health parameters to serve as the tuner vector. However, additional development is necessary to fully extend the methodology to Kalman filter

  3. Nootropic potential of Bauhinia variegata: A systematic study on murine model

    Directory of Open Access Journals (Sweden)

    Nishikant Jatav

    2014-01-01

    Full Text Available Objectives: Bauhinia variegata Linn (leguminosae is one of the important medicinal herbs used traditionally to treat fever, as tonic, astringent, diarrhea, dysentery, hemorrhoids, piles, edema. Recent findings on Bauhinia variegata Linn have demonstrated its antioxidant, anti-hyperlipidemic, and hepatoprotective potential. The present work is focused to evaluate nootropic potential of Bauhinia variegata Linn in rats. Materials and Methods: The leaves of Bauhinia variegata were collected in the month of January from Jawaharlal Nehru Krishi Vishwavidyalaya Jabalpur (Madhya Pradesh. Leaves were subjected for isolation of crude flavonoids and characterized by total flavonoid content assay. Flavonoid-rich extract of Bauhinia variegata was studied for acute oral toxicity as per revised Organization for Economic Cooperation & Development guidelines No. 423. Nootropic activity was determined by elevated plus maze, rotating rod apparatus, baclofen-induced catatonia, diazepam-induced amnesia. Results: Flavonoid-rich fraction of Bauhinia variegata caused no alteration in locomotion in animals. In the current study, animals treated with flavonoid-rich fraction of Bauhinia variegata (400 mg/kg showed a significant decrease in transfer latency as compared to the control group, which indicates cognitive enhancement effect flavonoid-rich fraction of Bauhinia variegata. In rota rod studies, flavonoid-rich fraction of Bauhinia variegata increased fall of time as compared to diazepam. In baclofen-induced catatonia, administration of flavonoid-rich fraction of Bauhinia variegata demonstrated protective effect on rats. Over all, flavonoid-rich fraction of Bauhinia variegata was found to enhance the performance of murine models. Conclusion: Thus, it could be concluded that flavonoids from Bauhinia variegata possess nootropic potential. However, more systematic studies are required to determine its exact mechanism of action.

  4. A fatal case of empyema thoracis: the price for underestimating odontogenic infections

    OpenAIRE

    Rowland Agbara; Athanasius Chukwudi Obiadazie; Sunday Ediagbini; Ikekhuamen Ernest

    2016-01-01

    Most dental infections are often underestimated by both patients and professional health care givers. When poorly managed, odontogenic infections may result in serious morbidity and life-threatening conditions. This article reports a fatal case of empyema thoracis in a 16-year-old male after an odontogenic infection. The challenges of management in our environment are discussed. Furthermore, the importance of understanding the route of spread after odontogenic infections is highlighted.

  5. A fatal case of empyema thoracis: the price for underestimating odontogenic infections

    Directory of Open Access Journals (Sweden)

    Rowland Agbara

    2016-06-01

    Full Text Available Most dental infections are often underestimated by both patients and professional health care givers. When poorly managed, odontogenic infections may result in serious morbidity and life-threatening conditions. This article reports a fatal case of empyema thoracis in a 16-year-old male after an odontogenic infection. The challenges of management in our environment are discussed. Furthermore, the importance of understanding the route of spread after odontogenic infections is highlighted.

  6. A systematic review of repetitive functional task practice with modelling of resource use, costs and effectiveness.

    Science.gov (United States)

    French, B; Leathley, M; Sutton, C; McAdam, J; Thomas, L; Forster, A; Langhorne, P; Price, C; Walker, A; Watkins, C

    2008-07-01

    To determine whether repetitive functional task practice (RFTP) after stroke improves limb-specific or global function or activities of daily living and whether treatment effects are dependent on the amount of practice, or the type or timing of the intervention. Also to provide estimates of the cost-effectiveness of RFTP. The main electronic databases were searched from inception to week 4, September 2006. Searches were also carried out on non-English-language databases and for unpublished trials up to May 2006. Standard quantitative methods were used to conduct the systematic review. The measures of efficacy of RFTP from the data synthesis were used to inform an economic model. The model used a pre-existing data set and tested the potential impact of RFTP on cost. An incremental cost per quality-adjusted life-year (QALY) gained for RFTP was estimated from the model. Sensitivity analyses around the assumptions made for the model were used to test the robustness of the estimates. Thirty-one trials with 34 intervention-control pairs and 1078 participants were included. Overall, it was found that some forms of RFTP resulted in improvement in global function, and in both arm and lower limb function. Overall standardised mean difference in data suitable for pooling was 0.38 [95% confidence interval (CI) 0.09 to 0.68] for global motor function, 0.24 (95% CI 0.06 to 0.42) for arm function and 0.28 (95% CI 0.05 to 0.51) for functional ambulation. Results suggest that training may be sufficient to have an impact on activities of daily living. Retention effects of training persist for up to 6 months, but whether they persist beyond this is unclear. There was little or no evidence that treatment effects overall were modified by time since stroke or dosage of task practice, but results for upper limb function were modified by type of intervention. The economic modelling suggested that RFTP was cost-effective. Given a threshold for cost-effectiveness of 20,000 pounds per QALY

  7. Is dream recall underestimated by retrospective measures and enhanced by keeping a logbook? An empirical investigation.

    Science.gov (United States)

    Aspy, Denholm J

    2016-05-01

    In a recent review, Aspy, Delfabbro, and Proeve (2015) highlighted the tendency for retrospective measures of dream recall to yield substantially lower recall rates than logbook measures, a phenomenon they termed the retrospective-logbook disparity. One explanation for this phenomenon is that retrospective measures underestimate true dream recall. Another explanation is that keeping a logbook tends to enhance dream recall. The present study provides a thorough empirical investigation into the retrospective-logbook disparity using a range of retrospective and logbook measures and three different types of logbook. Retrospective-logbook disparities were correlated with a range of variables theoretically related to the retrospective underestimation effect, and retrospective-logbook disparities were greater among participants that reported improved dream recall during the logbook period. These findings indicate that dream recall is underestimated by retrospective measures and enhanced by keeping a logbook. Recommendations for the use of retrospective and logbook measures of dream recall are provided. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. Sap flow is Underestimated by Thermal Dissipation Sensors due to Alterations of Wood Anatomy

    Science.gov (United States)

    Marañón-Jiménez, S.; Wiedemann, A.; van den Bulcke, J.; Cuntz, M.; Rebmann, C.; Steppe, K.

    2014-12-01

    The thermal dissipation technique (TD) is one of the most commonly adopted methods for sap flow measurements. However, underestimations of up to 60% of the tree transpiration have been reported with this technique, although the causes are not certainly known. The insertion of TD sensors within the stems causes damage of the wood tissue and subsequent healing reactions, changing wood anatomy and likely the sap flow path. However, the anatomical changes in response to the insertion of sap flow sensors and the effects on the measured flow have not been assessed yet. In this study, we investigate the alteration of vessel anatomy on wounds formed around TD sensors. Our main objectives were to elucidate the anatomical causes of sap flow underestimation for ring-porous and diffuse-porous species, and relate these changes to sap flow underestimations. Successive sets of TD probes were installed in early, mid and end of the growing season in Fagus sylvatica (diffuse-porous) and Quercus petraea (ring-porous) trees. They were logged after the growing season and additional sets of sensors were installed in the logged stems with presumably no healing reaction. The wood tissue surrounding each sensor was then excised and analysed by X-ray computed microtomography (X-ray micro CT). This technique allowed the quantification of vessel anatomical characteristics and the reconstruction of the 3-D internal microstructure of the xylem vessels so that extension and shape of the altered area could be determined. Gels and tyloses clogged the conductive vessels around the sensors in both beech and oak. The extension of the affected area was larger for beech although these anatomical changes led to similar sap flow underestimations in both species. The higher vessel size in oak may explain this result and, therefore, larger sap flow underestimation per area of affected conductive tissue. The wound healing reaction likely occurred within the first weeks after sensor installation, which

  9. How Much Do rRNA Gene Surveys Underestimate Extant Bacterial Diversity?

    Science.gov (United States)

    Rodriguez-R, Luis M; Castro, Juan C; Kyrpides, Nikos C; Cole, James R; Tiedje, James M; Konstantinidis, Konstantinos T

    2018-03-15

    The most common practice in studying and cataloguing prokaryotic diversity involves the grouping of sequences into operational taxonomic units (OTUs) at the 97% 16S rRNA gene sequence identity level, often using partial gene sequences, such as PCR-generated amplicons. Due to the high sequence conservation of rRNA genes, organisms belonging to closely related yet distinct species may be grouped under the same OTU. However, it remains unclear how much diversity has been underestimated by this practice. To address this question, we compared the OTUs of genomes defined at the 97% or 98.5% 16S rRNA gene identity level against OTUs of the same genomes defined at the 95% whole-genome average nucleotide identity (ANI), which is a much more accurate proxy for species. Our results show that OTUs resulting from a 98.5% 16S rRNA gene identity cutoff are more accurate than 97% compared to 95% ANI (90.5% versus 89.9% accuracy) but indistinguishable from any other threshold in the 98.29 to 98.78% range. Even with the more stringent thresholds, however, the 16S rRNA gene-based approach commonly underestimates the number of OTUs by ∼12%, on average, compared to the ANI-based approach (∼14% underestimation when using the 97% identity threshold). More importantly, the degree of underestimation can become 50% or more for certain taxa, such as the genera Pseudomonas , Burkholderia , Escherichia , Campylobacter , and Citrobacter These results provide a quantitative view of the degree of underestimation of extant prokaryotic diversity by 16S rRNA gene-defined OTUs and suggest that genomic resolution is often necessary. IMPORTANCE Species diversity is one of the most fundamental pieces of information for community ecology and conservational biology. Therefore, employing accurate proxies for what a species or the unit of diversity is are cornerstones for a large set of microbial ecology and diversity studies. The most common proxies currently used rely on the clustering of 16S r

  10. Prediction models for the mortality risk in chronic dialysis patients: a systematic review and independent external validation study

    Directory of Open Access Journals (Sweden)

    Ramspek CL

    2017-09-01

    Full Text Available Chava L Ramspek,1 Pauline WM Voskamp,1 Frans J van Ittersum,2 Raymond T Krediet,3 Friedo W Dekker,1 Merel van Diepen1 On behalf of the NECOSAD study group 1Department of Clinical Epidemiology, Leiden University Medical Center, Leiden, 2Department of Nephrology, VU University Medical Center, 3Department of Nephrology, Academic Medical Center, Amsterdam, The Netherlands Objective: In medicine, many more prediction models have been developed than are implemented or used in clinical practice. These models cannot be recommended for clinical use before external validity is established. Though various models to predict mortality in dialysis patients have been published, very few have been validated and none are used in routine clinical practice. The aim of the current study was to identify existing models for predicting mortality in dialysis patients through a review and subsequently to externally validate these models in the same large independent patient cohort, in order to assess and compare their predictive capacities.Methods: A systematic review was performed following the preferred reporting items for systematic reviews and meta-analyses (PRISMA guidelines. To account for missing data, multiple imputation was performed. The original prediction formulae were extracted from selected studies. The probability of death per model was calculated for each individual within the Netherlands Cooperative Study on the Adequacy of Dialysis (NECOSAD. The predictive performance of the models was assessed based on their discrimination and calibration.Results: In total, 16 articles were included in the systematic review. External validation was performed in 1,943 dialysis patients from NECOSAD for a total of seven models. The models performed moderately to well in terms of discrimination, with C-statistics ranging from 0.710 (interquartile range 0.708–0.711 to 0.752 (interquartile range 0.750–0.753 for a time frame of 1 year. According to the calibration, most

  11. More Use of Peritoneal Dialysis Gives Significant Savings: A Systematic Review and Health Economic Decision Model.

    Science.gov (United States)

    Pike, Eva; Hamidi, Vida; Ringerike, Tove; Wisloff, Torbjorn; Klemp, Marianne

    2017-02-01

    Patients with end-stage renal disease (ESRD) are in need of renal replacement therapy as dialysis and/or transplantation. The prevalence of ESRD and, thus, the need for dialysis are constantly growing. The dialysis modalities are either peritoneal performed at home or hemodialysis (HD) performed in-center (hospital or satellite) or home. We examined effectiveness and cost-effectiveness of HD performed at different locations (hospital, satellite, and home) and peritoneal dialysis (PD) at home in the Norwegian setting. We conducted a systematic review for patients above 18 years with end-stage renal failure requiring dialysis in several databases and performed several meta-analyses of existing literature. Mortality and major complications that required were our main clinical outcomes. The quality of the evidence for each outcome was evaluated using GRADE. Cost-effectiveness was assessed by developing a probabilistic Markov model. The analysis was carried out from a societal perspective, and effects were expressed in quality-adjusted life-years. Uncertainties in the base-case parameter values were explored with a probabilistic sensitivity analysis. Scenario analyses were conducted by increasing the proportion of patients receiving PD with a corresponding reduction in HD patients in-center both for Norway and Europian Union. We assumed an annual growth rate of 4% in the number of dialysis patients, and a relative distribution between PD and HD in-center of 30% and 70%, respectively. From a societal perspective and over a 5-year time horizon, PD was the most cost-effective dialysis alternative. We found no significant difference in mortality between peritoneal and HD modalities. Our scenario analyses showed that a shift toward more patients on PD (as a first choice) with a corresponding reduction in HD in-center gave a saving over a 5-year period of 32 and 10,623 million EURO, respectively, for Norway and the European Union. PD was the most cost-effective dialysis

  12. Regional estimation of groundwater arsenic concentrations through systematical dynamic-neural modeling

    Science.gov (United States)

    Chang, Fi-John; Chen, Pin-An; Liu, Chen-Wuing; Liao, Vivian Hsiu-Chuan; Liao, Chung-Min

    2013-08-01

    Arsenic (As) is an odorless semi-metal that occurs naturally in rock and soil, and As contamination in groundwater resources has become a serious threat to human health. Thus, assessing the spatial and temporal variability of As concentration is highly desirable, particularly in heavily As-contaminated areas. However, various difficulties may be encountered in the regional estimation of As concentration such as cost-intensive field monitoring, scarcity of field data, identification of important factors affecting As, over-fitting or poor estimation accuracy. This study develops a novel systematical dynamic-neural modeling (SDM) for effectively estimating regional As-contaminated water quality by using easily-measured water quality variables. To tackle the difficulties commonly encountered in regional estimation, the SDM comprises of a neural network and four statistical techniques: the Nonlinear Autoregressive with eXogenous input (NARX) network, Gamma test, cross-validation, Bayesian regularization method and indicator kriging (IK). For practical application, this study investigated a heavily As-contaminated area in Taiwan. The backpropagation neural network (BPNN) is adopted for comparison purpose. The results demonstrate that the NARX network (Root mean square error (RMSE): 95.11 μg l-1 for training; 106.13 μg l-1 for validation) outperforms the BPNN (RMSE: 121.54 μg l-1 for training; 143.37 μg l-1 for validation). The constructed SDM can provide reliable estimation (R2 > 0.89) of As concentration at ungauged sites based merely on three easily-measured water quality variables (Alk, Ca2+ and pH). In addition, risk maps under the threshold of the WHO drinking water standard (10 μg l-1) are derived by the IK to visually display the spatial and temporal variation of the As concentration in the whole study area at different time spans. The proposed SDM can be practically applied with satisfaction to the regional estimation in study areas of interest and the

  13. A permutation test to analyse systematic bias and random measurement errors of medical devices via boosting location and scale models.

    Science.gov (United States)

    Mayr, Andreas; Schmid, Matthias; Pfahlberg, Annette; Uter, Wolfgang; Gefeller, Olaf

    2017-06-01

    Measurement errors of medico-technical devices can be separated into systematic bias and random error. We propose a new method to address both simultaneously via generalized additive models for location, scale and shape (GAMLSS) in combination with permutation tests. More precisely, we extend a recently proposed boosting algorithm for GAMLSS to provide a test procedure to analyse potential device effects on the measurements. We carried out a large-scale simulation study to provide empirical evidence that our method is able to identify possible sources of systematic bias as well as random error under different conditions. Finally, we apply our approach to compare measurements of skin pigmentation from two different devices in an epidemiological study.

  14. Using Multimodal Learning Analytics to Model Student Behaviour: A Systematic Analysis of Behavioural Framing

    Science.gov (United States)

    Andrade, Alejandro; Delandshere, Ginette; Danish, Joshua A.

    2016-01-01

    One of the challenges many learning scientists face is the laborious task of coding large amounts of video data and consistently identifying social actions, which is time consuming and difficult to accomplish in a systematic and consistent manner. It is easier to catalog observable behaviours (e.g., body motions or gaze) without explicitly…

  15. Systematic screening for Chlamydia trachomatis : Estimating cost-effectiveness using dynamic modeling and Dutch data

    NARCIS (Netherlands)

    de Vries, R.; Van Bergen, J.E.A.M.; de Jong-van den Berg, Lolkje; Postma, Maarten

    2006-01-01

    To estimate the cost-effectiveness of a systematic one-off Chlamydia trachomatis (CT) screening program including partner treatment for Dutch young adults. Data on infection prevalence, participation rates, and sexual behavior were obtained from a large pilot study conducted in The Netherlands.

  16. Systematic screening for Chlamydia trachomatis: estimating cost-effectiveness using dynamic modeling and Dutch data

    NARCIS (Netherlands)

    de Vries, Robin; van Bergen, Jan E. A. M.; de Jong-van den Berg, Lolkje T. W.; Postma, Maarten J.

    2006-01-01

    To estimate the cost-effectiveness of a systematic one-off Chlamydia trachomatis (CT) screening program including partner treatment for Dutch young adults. Data on infection prevalence, participation rates, and sexual behavior were obtained from a large pilot study conducted in The Netherlands.

  17. Models and Theories of Health Education and Health Promotion in Physical Activity Interventions for Women: a Systematic Review

    Directory of Open Access Journals (Sweden)

    Seyed Mohammad Mehdi Hazavehei

    2014-09-01

    Full Text Available Introduction: The present study as a systematic review investigated and analyzed interventions based on models and theories of health education and promotion in the field of physical activity in women. Materials and Methods: Three electronic databases, including Springer, Biomed Central and Science Direct were searched systematically. Only studies were selected that were quantitative, interventional and in English language as well as those that used at least one of the models and theories of health education and health promotion. Finally, 13 studies were reviewed that met the inclusion criteria and published from 2000 to 2013. Results: Of 13 studies reviewed, 10 studies measured levels of physical activity before and after the intervention, which nine interventions increased physical activity in the intervention group compared to the control group. Studies were conducted in different settings of health promotion including health care centers, community setting and workplace. The most widely used model was the Transtheoretical Model applied in eight of investigations. Conclusion: It is suggested to focus more on physical activity and duration of interventions to increase the efficacy of interventions. It is suggested to measure changes of physical activity habits in experimental and control groups in interventions based on the transtheoretical model to prepare a complementary scale to assess the efficacy of interventions. According to the results, no study had focused on changes in institutional policies or general health or providing changes in environment related to physical activity.

  18. Screening and vaccination as determined by the Social Ecological Model and the Theory of Triadic Influence: a systematic review.

    Science.gov (United States)

    Nyambe, Anayawa; Van Hal, Guido; Kampen, Jarl K

    2016-11-17

    Vaccination and screening are forms of primary and secondary prevention methods. These methods are recommended for controlling the spread of a vast number of diseases and conditions. To determine the most effective preventive methods to be used by a society, multi-level models have shown to be more effective than models that focus solely on individual level characteristics. The Social Ecological Model (SEM) and the Theory of Triadic Influence (TTI) are such models. The purpose of this systematic review was to identify main differences and similarities of SEM and TTI regarding screening and vaccination in order to prepare potentially successful prevention programs for practice. A systematic review was conducted. Separate literature searches were performed during January and February 2015 using Medline, Ovid, Proquest, PubMed, University of Antwerp Discovery Service and Web of Science, for articles that apply the SEM and TTI. A Data Extraction Form with mostly closed-end questions was developed to assist with data extraction. Aggregate descriptive statistics were utilized to summarize the general characteristics of the SEM and TTI as documented in the scientific literature. A total of 290 potentially relevant articles referencing the SEM were found. As for the TTI, a total of 131 potentially relevant articles were found. After strict evaluation for inclusion and exclusion criteria, 40 SEM studies and 46 TTI studies were included in the systematic review. The SEM and TTI are theoretical frameworks that share many theoretical concepts and are relevant for several types of health behaviors. However, they differ in the structure of the model, and in how the variables are thought to interact with each other, the TTI being a matrix while the SEM has a ring structure. The main difference consists of the division of the TTI into levels of causation (ultimate, distal and proximal) which are not considered within the levels of the SEM. It was further found that in the articles

  19. Commonly used reference values underestimate oxygen uptake in healthy, 50-year-old Swedish women.

    Science.gov (United States)

    Genberg, M; Andrén, B; Lind, L; Hedenström, H; Malinovschi, A

    2018-01-01

    Cardiopulmonary exercise testing (CPET) is the gold standard among clinical exercise tests. It combines a conventional stress test with measurement of oxygen uptake (V O 2 ) and CO 2 production. No validated Swedish reference values exist, and reference values in women are generally understudied. Moreover, the importance of achieved respiratory exchange ratio (RER) and the significance of breathing reserve (BR) at peak exercise in healthy individuals are poorly understood. We compared V O 2 at maximal load (peakV O 2 ) and anaerobic threshold (V O 2@ AT ) in healthy Swedish individuals with commonly used reference values, taking gender into account. Further, we analysed maximal workload and peakV O 2 with regard to peak RER and BR. In all, 181 healthy, 50-year-old individuals (91 women) performed CPET. PeakV O 2 was best predicted using Jones et al. (100·5%), while SHIP reference values underestimated peakV O 2 most: 112·5%. Furthermore, underestimation of peakV O 2 in women was found for all studied reference values (P 1·1 (2 328·7 versus 2 176·7 ml min -1 , P = 0·11). Lower BR (≤30%) related to significantly higher peakV O 2 (Pvalues underestimated oxygen uptake in women. No evidence for demanding RER > 1·1 in healthy individuals was found. A lowered BR is probably a normal response to higher workloads in healthy individuals. © 2016 Scandinavian Society of Clinical Physiology and Nuclear Medicine. Published by John Wiley & Sons Ltd.

  20. Attaining Performance with Building Information Modelling : A systematic literature review of product and process modelling in AEC

    NARCIS (Netherlands)

    Papadonikolaki, E.; Koutamanis, A.; Wamelink, J.W.F.

    2013-01-01

    The paper presents the findings of a systematic literature review of approximately 200 scientific sources. It is designed with the aim to identify the current benefits and factors of high performance in Architecture, Engineering, Construction (AEC) since the introduction of Building Information

  1. Whole-word response scoring underestimates functional spelling ability for some individuals with global agraphia

    Directory of Open Access Journals (Sweden)

    Andrew Tesla Demarco

    2015-05-01

    These data suggest that conventional whole-word scoring may significantly underestimate functional spelling performance. Because by-letter scoring boosted pre-treatment scores to the same extent as post-treatment scores, the magnitude of treatment gains was no greater than estimates from conventional whole-word scoring. Nonetheless, the surprisingly large disparity between conventional whole-word scoring and by-letter scoring suggests that by-letter scoring methods may warrant further investigation. Because by-letter analyses may hold interest to others, we plan to make the software tool used in this study available on-line for use to researchers and clinicians at large.

  2. Tumor cells growth and survival time with the ketogenic diet in animal models: A systematic review

    Directory of Open Access Journals (Sweden)

    Soheila Khodadadi

    2017-01-01

    Full Text Available Recently, interest in targeted cancer therapies via metabolic pathways has been renewed with the discovery that many tumors become dependent on glucose uptake during anaerobic glycolysis. Also the inability of ketone bodies metabolization due to various deficiencies in mitochondrial enzymes is the major metabolic changes discovered in malignant cells. Therefore, administration of a ketogenic diet (KD which is based on high in fat and low in carbohydrates might inhibit tumor growth and provide a rationale for therapeutic strategies. So, we conducted this systematic review to assess the effects of KD on the tumor cells growth and survival time in animal studies. All databases were searched from inception to November 2015. We systematically searched the PubMed, Scopus, Google Scholars, Science Direct and Cochrane Library according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. To assess the quality of included studies we used SYRCLE's RoB tool. 268 articles were obtained from databases by primary search. Only 13 studies were eligible according to inclusion criteria. From included studies, 9 articles indicate that KD had a beneficial effect on tumor growth and survival time. Tumor types were included pancreatic, prostate, gastric, colon, brain, neuroblastoma and lung cancers. In conclusions, although studies in this field are rare and inconsistence, recent findings have demonstrated that KD can potentially inhibit the malignant cell growth and increase the survival time. Because of differences physiology between animals and humans, future studies in cancer patients treated with a KD are needed.

  3. Tumor Cells Growth and Survival Time with the Ketogenic Diet in Animal Models: A Systematic Review.

    Science.gov (United States)

    Khodadadi, Soheila; Sobhani, Nafiseh; Mirshekar, Somaye; Ghiasvand, Reza; Pourmasoumi, Makan; Miraghajani, Maryam; Dehsoukhteh, Somayeh Shahraki

    2017-01-01

    Recently, interest in targeted cancer therapies via metabolic pathways has been renewed with the discovery that many tumors become dependent on glucose uptake during anaerobic glycolysis. Also the inability of ketone bodies metabolization due to various deficiencies in mitochondrial enzymes is the major metabolic changes discovered in malignant cells. Therefore, administration of a ketogenic diet (KD) which is based on high in fat and low in carbohydrates might inhibit tumor growth and provide a rationale for therapeutic strategies. So, we conducted this systematic review to assess the effects of KD on the tumor cells growth and survival time in animal studies. All databases were searched from inception to November 2015. We systematically searched the PubMed, Scopus, Google Scholars, Science Direct and Cochrane Library according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. To assess the quality of included studies we used SYRCLE's RoB tool. 268 articles were obtained from databases by primary search. Only 13 studies were eligible according to inclusion criteria. From included studies, 9 articles indicate that KD had a beneficial effect on tumor growth and survival time. Tumor types were included pancreatic, prostate, gastric, colon, brain, neuroblastoma and lung cancers. In conclusions, although studies in this field are rare and inconsistence, recent findings have demonstrated that KD can potentially inhibit the malignant cell growth and increase the survival time. Because of differences physiology between animals and humans, future studies in cancer patients treated with a KD are needed.

  4. A systematic review of approaches to modelling lower limb muscle forces during gait: Applicability to clinical gait analyses.

    Science.gov (United States)

    Trinler, Ursula; Hollands, Kristen; Jones, Richard; Baker, Richard

    2018-03-01

    Computational methods to estimate muscle forces during walking are becoming more common in biomechanical research but not yet in clinical gait analysis. This systematic review aims to identify the current state-of-the-art, examine the differences between approaches, and consider applicability of the current approaches in clinical gait analysis. A systematic database search identified studies including estimated muscle force profiles of the lower limb during healthy walking. These were rated for quality and the muscle force profiles digitised for comparison. From 13.449 identified studies, 22 were finally included which used four modelling approaches: static optimisation, enhanced static optimisation, forward dynamics and EMG-driven. These used a range of different musculoskeletal models, muscle-tendon characteristics and cost functions. There is visually broad agreement between and within approaches about when muscles are active throughout the gait cycle. There remain, considerable differences (CV 7%-151%, range of timing of peak forces in gait cycle 1%-31%) in patterns and magnitudes of force between and within modelling approaches. The main source of this variability is not clear. Different musculoskeletal models, experimental protocols, and modelling approaches will clearly have an effect as will the variability of joint kinetics between healthy individuals. Limited validation of modelling approaches, particularly at the level of individual participants, makes it difficult to conclude if any of the approaches give consistently better estimates than others. While muscle force modelling has clear potential to enhance clinical gait analyses future research is needed to improve validation, accuracy and feasibility of implementation in clinical practice. Copyright © 2018 Elsevier B.V. All rights reserved.

  5. Drastic underestimation of amphipod biodiversity in the endangered Irano-Anatolian and Caucasus biodiversity hotspots.

    Science.gov (United States)

    Katouzian, Ahmad-Reza; Sari, Alireza; Macher, Jan N; Weiss, Martina; Saboori, Alireza; Leese, Florian; Weigand, Alexander M

    2016-03-01

    Biodiversity hotspots are centers of biological diversity and particularly threatened by anthropogenic activities. Their true magnitude of species diversity and endemism, however, is still largely unknown as species diversity is traditionally assessed using morphological descriptions only, thereby ignoring cryptic species. This directly limits evidence-based monitoring and management strategies. Here we used molecular species delimitation methods to quantify cryptic diversity of the montane amphipods in the Irano-Anatolian and Caucasus biodiversity hotspots. Amphipods are ecosystem engineers in rivers and lakes. Species diversity was assessed by analysing two genetic markers (mitochondrial COI and nuclear 28S rDNA), compared with morphological assignments. Our results unambiguously demonstrate that species diversity and endemism is dramatically underestimated, with 42 genetically identified freshwater species in only five reported morphospecies. Over 90% of the newly recovered species cluster inside Gammarus komareki and G. lacustris; 69% of the recovered species comprise narrow range endemics. Amphipod biodiversity is drastically underestimated for the studied regions. Thus, the risk of biodiversity loss is significantly greater than currently inferred as most endangered species remain unrecognized and/or are only found locally. Integrative application of genetic assessments in monitoring programs will help to understand the true magnitude of biodiversity and accurately evaluate its threat status.

  6. Quantifying the underestimation of relative risks from genome-wide association studies.

    Directory of Open Access Journals (Sweden)

    Chris Spencer

    2011-03-01

    Full Text Available Genome-wide association studies (GWAS have identified hundreds of associated loci across many common diseases. Most risk variants identified by GWAS will merely be tags for as-yet-unknown causal variants. It is therefore possible that identification of the causal variant, by fine mapping, will identify alleles with larger effects on genetic risk than those currently estimated from GWAS replication studies. We show that under plausible assumptions, whilst the majority of the per-allele relative risks (RR estimated from GWAS data will be close to the true risk at the causal variant, some could be considerable underestimates. For example, for an estimated RR in the range 1.2-1.3, there is approximately a 38% chance that it exceeds 1.4 and a 10% chance that it is over 2. We show how these probabilities can vary depending on the true effects associated with low-frequency variants and on the minor allele frequency (MAF of the most associated SNP. We investigate the consequences of the underestimation of effect sizes for predictions of an individual's disease risk and interpret our results for the design of fine mapping experiments. Although these effects mean that the amount of heritability explained by known GWAS loci is expected to be larger than current projections, this increase is likely to explain a relatively small amount of the so-called "missing" heritability.

  7. Underestimated risks of recurrent long-range ash dispersal from northern Pacific Arc volcanoes

    Science.gov (United States)

    Bourne, A. J.; Abbott, P. M.; Albert, P. G.; Cook, E.; Pearce, N. J. G.; Ponomareva, V.; Svensson, A.; Davies, S. M.

    2016-07-01

    Widespread ash dispersal poses a significant natural hazard to society, particularly in relation to disruption to aviation. Assessing the extent of the threat of far-travelled ash clouds on flight paths is substantially hindered by an incomplete volcanic history and an underestimation of the potential reach of distant eruptive centres. The risk of extensive ash clouds to aviation is thus poorly quantified. New evidence is presented of explosive Late Pleistocene eruptions in the Pacific Arc, currently undocumented in the proximal geological record, which dispersed ash up to 8000 km from source. Twelve microscopic ash deposits or cryptotephra, invisible to the naked eye, discovered within Greenland ice-cores, and ranging in age between 11.1 and 83.7 ka b2k, are compositionally matched to northern Pacific Arc sources including Japan, Kamchatka, Cascades and Alaska. Only two cryptotephra deposits are correlated to known high-magnitude eruptions (Towada-H, Japan, ca 15 ka BP and Mount St Helens Set M, ca 28 ka BP). For the remaining 10 deposits, there is no evidence of age- and compositionally-equivalent eruptive events in regional volcanic stratigraphies. This highlights the inherent problem of under-reporting eruptions and the dangers of underestimating the long-term risk of widespread ash dispersal for trans-Pacific and trans-Atlantic flight routes.

  8. Application of analytic hierarchy process-grey target theory systematic model in comprehensive evaluation of water environmental quality.

    Science.gov (United States)

    Wu, Jun; Tian, Xiaogang; Tang, Ya; Zhao, Yujie; Hu, Yandi; Fang, Zili

    2010-07-01

    Comprehensive evaluation of the water environment for effective water quality management is complicated by a considerable number of factors and uncertainties. It is difficult to combine micro-evaluation with the macro-evaluation process. To effectively eliminate the subjective errors of the traditional analytic hierarchy process (AHP), a new modeling approach--the analytic hierarchy process and grey target theory (AHP-GTT) systematic model--is presented in this study to evaluate water quality in a certain watershed. A case study of applying the AHP-GTT systematic model to the evaluation and analysis of the water environment was conducted in the Yibin section of the Yangtze River, China. The micro-evaluation is based on defining the weights of indices of the water quality (IWQ) of each water cross-section, while the macro-evaluation is based on calculating the comprehensive indices of water environmental quality and analyzing the tendency of the water environment of each cross-section. The results indicated that the Baixi and Shuidongmen sections are seriously polluted areas, with the tendencies of becoming worse. Also, the key IWQs of these two cross-sections are 5-day biochemical oxygen demand and chemical oxygen demand of permanganate, respectively.

  9. Few promising multivariable prognostic models exist for recovery of people with non-specific neck pain in musculoskeletal primary care: A systematic review

    NARCIS (Netherlands)

    R.W. Wingbermühle (Roel); E. van Trijffel (Emiel); Nelissen, P.M. (Paul M.); B.W. Koes (Bart); A.P. Verhagen (Arianne)

    2017-01-01

    markdownabstractQuestion: Which multivariable prognostic model(s) for recovery in people with neck pain can be used in primary care? Design: Systematic review of studies evaluating multivariable prognostic models. Participants: People with non-specific neck pain presenting at primary care.

  10. Individual, premigration and postsettlement factors, and academic achievement in adolescents from refugee backgrounds: A systematic review and model.

    Science.gov (United States)

    Wong, Charissa W S; Schweitzer, Robert D

    2017-01-01

    We have limited understanding of the precursors of academic achievement in resettled adolescents from refugee backgrounds. To date, no clear model has been developed to conceptualise the academic trajectories of adolescents from refugee backgrounds at postsettlement. The current review had two aims. First, to propose an integrated adaptive model to conceptualise the impact of individual, premigration, and postsettlement factors on academic achievement at postsettlement; and second, to critically examine the literature on factors that predict academic achievement in adolescents from refugee backgrounds in relation to the proposed model and highlight issues deserving future exploration. Following the protocol of a systematic literature review, 13 studies were identified for full-text review. Gender, ethnicity, English proficiency, psychological distress, premigration trauma, premigration loss, postsettlement social support, and postsettlement school connectedness, were found to predict academic achievement in adolescents from refugee backgrounds.

  11. Immunosuppressive therapy for kidney transplantation in adults: a systematic review and economic model.

    Science.gov (United States)

    Jones-Hughes, Tracey; Snowsill, Tristan; Haasova, Marcela; Coelho, Helen; Crathorne, Louise; Cooper, Chris; Mujica-Mota, Ruben; Peters, Jaime; Varley-Campbell, Jo; Huxley, Nicola; Moore, Jason; Allwood, Matt; Lowe, Jenny; Hyde, Chris; Hoyle, Martin; Bond, Mary; Anderson, Rob

    2016-08-01

    End-stage renal disease is a long-term irreversible decline in kidney function requiring renal replacement therapy: kidney transplantation, haemodialysis or peritoneal dialysis. The preferred option is kidney transplantation, followed by immunosuppressive therapy (induction and maintenance therapy) to reduce the risk of kidney rejection and prolong graft survival. To review and update the evidence for the clinical effectiveness and cost-effectiveness of basiliximab (BAS) (Simulect(®), Novartis Pharmaceuticals UK Ltd) and rabbit anti-human thymocyte immunoglobulin (rATG) (Thymoglobulin(®), Sanofi) as induction therapy, and immediate-release tacrolimus (TAC) (Adoport(®), Sandoz; Capexion(®), Mylan; Modigraf(®), Astellas Pharma; Perixis(®), Accord Healthcare; Prograf(®), Astellas Pharma; Tacni(®), Teva; Vivadex(®), Dexcel Pharma), prolonged-release tacrolimus (Advagraf(®) Astellas Pharma), belatacept (BEL) (Nulojix(®), Bristol-Myers Squibb), mycophenolate mofetil (MMF) (Arzip(®), Zentiva; CellCept(®), Roche Products; Myfenax(®), Teva), mycophenolate sodium (MPS) (Myfortic(®), Novartis Pharmaceuticals UK Ltd), sirolimus (SRL) (Rapamune(®), Pfizer) and everolimus (EVL) (Certican(®), Novartis) as maintenance therapy in adult renal transplantation. Clinical effectiveness searches were conducted until 18 November 2014 in MEDLINE (via Ovid), EMBASE (via Ovid), Cochrane Central Register of Controlled Trials (via Wiley Online Library) and Web of Science (via ISI), Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effects and Health Technology Assessment (The Cochrane Library via Wiley Online Library) and Health Management Information Consortium (via Ovid). Cost-effectiveness searches were conducted until 18 November 2014 using a costs or economic literature search filter in MEDLINE (via Ovid), EMBASE (via Ovid), NHS Economic Evaluation Database (via Wiley Online Library), Web of Science (via ISI), Health Economic Evaluations

  12. redGEM: Systematic reduction and analysis of genome-scale metabolic reconstructions for development of consistent core metabolic models.

    Directory of Open Access Journals (Sweden)

    Meric Ataman

    2017-07-01

    Full Text Available Genome-scale metabolic reconstructions have proven to be valuable resources in enhancing our understanding of metabolic networks as they encapsulate all known metabolic capabilities of the organisms from genes to proteins to their functions. However the complexity of these large metabolic networks often hinders their utility in various practical applications. Although reduced models are commonly used for modeling and in integrating experimental data, they are often inconsistent across different studies and laboratories due to different criteria and detail, which can compromise transferability of the findings and also integration of experimental data from different groups. In this study, we have developed a systematic semi-automatic approach to reduce genome-scale models into core models in a consistent and logical manner focusing on the central metabolism or subsystems of interest. The method minimizes the loss of information using an approach that combines graph-based search and optimization methods. The resulting core models are shown to be able to capture key properties of the genome-scale models and preserve consistency in terms of biomass and by-product yields, flux and concentration variability and gene essentiality. The development of these "consistently-reduced" models will help to clarify and facilitate integration of different experimental data to draw new understanding that can be directly extendable to genome-scale models.

  13. Study on the systematic approach of Markov modeling for dependability analysis of complex fault-tolerant features with voting logics

    International Nuclear Information System (INIS)

    Son, Kwang Seop; Kim, Dong Hoon; Kim, Chang Hwoi; Kang, Hyun Gook

    2016-01-01

    The Markov analysis is a technique for modeling system state transitions and calculating the probability of reaching various system states. While it is a proper tool for modeling complex system designs involving timing, sequencing, repair, redundancy, and fault tolerance, as the complexity or size of the system increases, so does the number of states of interest, leading to difficulty in constructing and solving the Markov model. This paper introduces a systematic approach of Markov modeling to analyze the dependability of a complex fault-tolerant system. This method is based on the decomposition of the system into independent subsystem sets, and the system-level failure rate and the unavailability rate for the decomposed subsystems. A Markov model for the target system is easily constructed using the system-level failure and unavailability rates for the subsystems, which can be treated separately. This approach can decrease the number of states to consider simultaneously in the target system by building Markov models of the independent subsystems stage by stage, and results in an exact solution for the Markov model of the whole target system. To apply this method we construct a Markov model for the reactor protection system found in nuclear power plants, a system configured with four identical channels and various fault-tolerant architectures. The results show that the proposed method in this study treats the complex architecture of the system in an efficient manner using the merits of the Markov model, such as a time dependent analysis and a sequential process analysis. - Highlights: • Systematic approach of Markov modeling for system dependability analysis is proposed based on the independent subsystem set, its failure rate and unavailability rate. • As an application example, we construct the Markov model for the digital reactor protection system configured with four identical and independent channels, and various fault-tolerant architectures. • The

  14. Integrated methodological frameworks for modelling agent-based advanced supply chain planning systems: A systematic literature review

    Directory of Open Access Journals (Sweden)

    Luis Antonio Santa-Eulalia

    2011-12-01

    Full Text Available Purpose: The objective of this paper is to provide a systematic literature review of recent developments in methodological frameworks for the modelling and simulation of agent-based advanced supply chain planning systems.Design/methodology/approach: A systematic literature review is provided to identify, select and make an analysis and a critical summary of all suitable studies in the area. It is organized into two blocks: the first one covers agent-based supply chain planning systems in general terms, while the second one specializes the previous search to identify those works explicitly containing methodological aspects.Findings: Among sixty suitable manuscripts identified in the primary literature search, only seven explicitly considered the methodological aspects. In addition, we noted that, in general, the notion of advanced supply chain planning is not considered unambiguously, that the social and individual aspects of the agent society are not taken into account in a clear manner in several studies and that a significant part of the works are of a theoretical nature, with few real-scale industrial applications. An integrated framework covering all phases of the modelling and simulation process is still lacking in the literature visited.Research limitations/implications: The main research limitations are related to the period covered (last four years, the selected scientific databases, the selected language (i.e. English and the use of only one assessment framework for the descriptive evaluation part.Practical implications: The identification of recent works in the domain and discussion concerning their limitations can help pave the way for new and innovative researches towards a complete methodological framework for agent-based advanced supply chain planning systems.Originality/value: As there are no recent state-of-the-art reviews in the domain of methodological frameworks for agent-based supply chain planning, this paper contributes to

  15. Life course socio-economic position and quality of life in adulthood: a systematic review of life course models

    Science.gov (United States)

    2012-01-01

    Background A relationship between current socio-economic position and subjective quality of life has been demonstrated, using wellbeing, life and needs satisfaction approaches. Less is known regarding the influence of different life course socio-economic trajectories on later quality of life. Several conceptual models have been proposed to help explain potential life course effects on health, including accumulation, latent, pathway and social mobility models. This systematic review aimed to assess whether evidence supported an overall relationship between life course socio-economic position and quality of life during adulthood and if so, whether there was support for one or more life course models. Methods A review protocol was developed detailing explicit inclusion and exclusion criteria, search terms, data extraction items and quality appraisal procedures. Literature searches were performed in 12 electronic databases during January 2012 and the references and citations of included articles were checked for additional relevant articles. Narrative synthesis was used to analyze extracted data and studies were categorized based on the life course model analyzed. Results Twelve studies met the eligibility criteria and used data from 10 datasets and five countries. Study quality varied and heterogeneity between studies was high. Seven studies assessed social mobility models, five assessed the latent model, two assessed the pathway model and three tested the accumulation model. Evidence indicated an overall relationship, but mixed results were found for each life course model. Some evidence was found to support the latent model among women, but not men. Social mobility models were supported in some studies, but overall evidence suggested little to no effect. Few studies addressed accumulation and pathway effects and study heterogeneity limited synthesis. Conclusions To improve potential for synthesis in this area, future research should aim to increase study

  16. Risk prediction models for delirium in the intensive care unit after cardiac surgery: a systematic review and independent external validation.

    Science.gov (United States)

    Lee, A; Mu, J L; Joynt, G M; Chiu, C H; Lai, V K W; Gin, T; Underwood, M J

    2017-03-01

    Numerous risk prediction models are available for predicting delirium after cardiac surgery, but few have been directly compared with one another or been validated in an independent data set. We conducted a systematic review to identify validated risk prediction models of delirium (using the Confusion Assessment Method-Intensive Care Unit tool) after cardiac surgery and assessed the transportability of the risk prediction models on a prospective cohort of 600 consecutive patients undergoing cardiac surgery at a university hospital in Hong Kong from July 2013 to July 2015. The discrimination (c-statistic), calibration (GiViTI calibration belt), and clinical usefulness (decision curve analysis) of the risk prediction models were examined in a stepwise manner. Three published high-quality intensive care unit delirium risk prediction models (n=5939) were identified: Katznelson, the original PRE-DELIRIC, and the international recalibrated PRE-DELIRIC model. Delirium occurred in 83 patients (13.8%, 95% CI: 11.2-16.9%). After updating the intercept and regression coefficients in the Katznelson model, there was fair discrimination (0.62, 95% CI: 0.58-0.66) and good calibration. As the original PRE-DELIRIC model was already validated externally and recalibrated in six countries, we performed a logistic calibration on the recalibrated model and found acceptable discrimination (0.75, 95% CI: 0.72-0.79) and good calibration. Decision curve analysis demonstrated that the recalibrated PRE-DELIRIC risk model was marginally more clinically useful than the Katznelson model. Current models predict delirium risk in the intensive care unit after cardiac surgery with only fair to moderate accuracy and are insufficient for routine clinical use. © The Author 2017. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  17. Methodologies used in cost-effectiveness models for evaluating treatments in major depressive disorder: a systematic review

    Directory of Open Access Journals (Sweden)

    Zimovetz Evelina A

    2012-02-01

    Full Text Available Abstract Background Decision makers in many jurisdictions use cost-effectiveness estimates as an aid for selecting interventions with an appropriate balance between health benefits and costs. This systematic literature review aims to provide an overview of published cost-effectiveness models in major depressive disorder (MDD with a focus on the methods employed. Key components of the identified models are discussed and any challenges in developing models are highlighted. Methods A systematic literature search was performed to identify all primary model-based economic evaluations of MDD interventions indexed in MEDLINE, the Cochrane Library, EMBASE, EconLit, and PsycINFO between January 2000 and May 2010. Results A total of 37 studies were included in the review. These studies predominantly evaluated antidepressant medications. The analyses were performed across a broad set of countries. The majority of models were decision-trees; eight were Markov models. Most models had a time horizon of less than 1 year. The majority of analyses took a payer perspective. Clinical input data were obtained from pooled placebo-controlled comparative trials, single head-to-head trials, or meta-analyses. The majority of studies (24 of 37 used treatment success or symptom-free days as main outcomes, 14 studies incorporated health state utilities, and 2 used disability-adjusted life-years. A few models (14 of 37 incorporated probabilities and costs associated with suicide and/or suicide attempts. Two models examined the cost-effectiveness of second-line treatment in patients who had failed to respond to initial therapy. Resource use data used in the models were obtained mostly from expert opinion. All studies, with the exception of one, explored parameter uncertainty. Conclusions The review identified several model input data gaps, including utility values in partial responders, efficacy of second-line treatments, and resource utilisation estimates obtained from

  18. Surgeons often underestimate the amount of blood loss in replacement surgeries

    Directory of Open Access Journals (Sweden)

    Ram Ganesan Ganesan

    2014-07-01

    Full Text Available 【Abstract】Objective:To assess the accuracy of the clinically estimated blood loss (EBL when compared with the actual blood loss (ABL in replacement surgeries. Methods: This prospective study was done in Sri Ramachandra Medical Centre from April 2011 to April 2013. Altogether 140 patients undergoing total hip replacement or total knee replacement were included with the inclusion criteria being patients with haemoglobin higher than 100 g/ml and coagulation profile within normal limits. Exclusion criteria were intake of antiplatelet drug or anti-coagulant, bleeding disorders, thrombotic episode, and haematological disorders. There were 65 men and 75 women. In this study, the consultants were free to use any clinical method to estimate the blood loss, including counting the blood-soaked mops and gauze pieces (estimating the volume of blood carried in all the mops and gauzes, measuring blood lost to suction bottles and blood in and around the operative field. The ABL was calculated based on a modification of the Gross’s formula using haematocrit values. Results: In 42 of the 140 cases, the EBL exceeded the ABL. These cases had a negative difference in blood loss (or DIFF-BL<0 and were included in the overestimation group, which accounted for 30% of the study population. Of the remaining 98 cases (70%, the ABL exceeded the EBL. Therefore they were put into the underestimation group who had a positive difference in blood loss (DIFF-BL>0. We found that when the average blood loss was small, the accuracy of estimation was high. But when the average blood loss exceeded 500 ml, the accuracy rate decreased significantly. This suggested that clinical estimation is inaccurate with the increase of blood loss. Conclusion:This study has shown that using clinical estimation alone to guide blood transfusion is inadequate. In this study, 70% of patients had their blood loss underestimated, proving that surgeons often underestimate blood loss in replacement

  19. Leaders' experiences and perceptions implementing activity-based funding and pay-for-performance hospital funding models: A systematic review.

    Science.gov (United States)

    Baxter, Pamela E; Hewko, Sarah J; Pfaff, Kathryn A; Cleghorn, Laura; Cunningham, Barbara J; Elston, Dawn; Cummings, Greta G

    2015-08-01

    Providing cost-effective, accessible, high quality patient care is a challenge to governments and health care delivery systems across the globe. In response to this challenge, two types of hospital funding models have been widely implemented: (1) activity-based funding (ABF) and (2) pay-for-performance (P4P). Although health care leaders play a critical role in the implementation of these funding models, to date their perspectives have not been systematically examined. The purpose of this systematic review was to gain a better understanding of the experiences of health care leaders implementing hospital funding reforms within Organisation for Economic Cooperation and Development countries. We searched literature from 1982 to 2013 using: Medline, EMBASE, CINAHL, Academic Search Complete, Academic Search Elite, and Business Source Complete. Two independent reviewers screened titles, abstracts and full texts using predefined criteria. We included 2 mixed methods and 12 qualitative studies. Thematic analysis was used in synthesizing results. Five common themes and multiple subthemes emerged. Themes include: pre-requisites for success, perceived benefits, barriers/challenges, unintended consequences, and leader recommendations. Irrespective of which type of hospital funding reform was implemented, health care leaders described a complex process requiring the following: organizational commitment; adequate infrastructure; human, financial and information technology resources; change champions and a personal commitment to quality care. Crown Copyright © 2015. Published by Elsevier Ireland Ltd. All rights reserved.

  20. Efficient trawl avoidance by mesopelagic fishes causes large underestimation of their biomass

    KAUST Repository

    Kaartvedt, Stein

    2012-06-07

    Mesopelagic fishes occur in all the world’s oceans, but their abundance and consequently their ecological significance remains uncertain. The current global estimate based on net sampling prior to 1980 suggests a global abundance of one gigatonne (109 t) wet weight. Here we report novel evidence of efficient avoidance of such sampling by the most common myctophid fish in the Northern Atlantic, i.e. Benthosema glaciale. We reason that similar avoidance of nets may explain consistently higher acoustic abundance estimates of mesopelagic fish from different parts of the world’s oceans. It appears that mesopelagic fish abundance may be underestimated by one order of magnitude, suggesting that the role of mesopelagic fish in the oceans might need to be revised.

  1. Does the Congressional Budget Office underestimate savings from reform? A review of the historical record.

    Science.gov (United States)

    Gabel, Jon R

    2010-01-01

    When the Congressional Budget Office (CBO) "scores" legislation, or assesses the likely cost impact, it requires substantial evidence that a cost-saving initiative has historically achieved savings. The agency has difficulty addressing the impact of multiple changes made simultaneously without historical precedent where there is an interaction effect among proposed changes. This study examines CBO scoring of major reform legislation enacted during each of the past three decades, including the prospective payment system for hospitals in the 1980s, the Balanced Budget Act of the 1990s, and the Medicare Modernization Act of 2003. In contrasting actual spending with predicted spending, CBO, in all three cases, substantially underestimated savings from these reform measures.

  2. Dynamic left ventricular outflow tract obstruction: underestimated cause of hypotension and hemodynamic instability

    Directory of Open Access Journals (Sweden)

    Dorota Sobczyk

    2014-12-01

    Full Text Available Left ventricular outflow tract obstruction, which is typically associated with hypertrophic cardiomyopathy, is the third most frequent cause of unexplained hypotension. This underestimated problem may temporarily accompany various diseases (it is found in even <1% of patients with no tangible cardiac disease and clinical situations (hypovolemia, general anesthesia. It is currently assumed that left ventricular outflow tract obstruction is a dynamic phenomenon, the occurrence of which requires the coexistence of predisposing anatomic factors and a physiological condition that induces it. The diagnosis of left ventricular outflow tract obstruction should entail immediate implementation of the therapy to eliminate the factors that can potentially intensify the obstruction. Echocardiography is the basic modality in the diagnosis and treatment of left ventricular outflow tract obstruction. This paper presents four patients in whom the immediate implementation of bedside echocardiography enabled a rapid diagnosis of left ventricular outflow tract obstruction and implementation of proper treatment.

  3. How and why DNA barcodes underestimate the diversity of microbial eukaryotes.

    Directory of Open Access Journals (Sweden)

    Gwenael Piganeau

    Full Text Available BACKGROUND: Because many picoplanktonic eukaryotic species cannot currently be maintained in culture, direct sequencing of PCR-amplified 18S ribosomal gene DNA fragments from filtered sea-water has been successfully used to investigate the astounding diversity of these organisms. The recognition of many novel planktonic organisms is thus based solely on their 18S rDNA sequence. However, a species delimited by its 18S rDNA sequence might contain many cryptic species, which are highly differentiated in their protein coding sequences. PRINCIPAL FINDINGS: Here, we investigate the issue of species identification from one gene to the whole genome sequence. Using 52 whole genome DNA sequences, we estimated the global genetic divergence in protein coding genes between organisms from different lineages and compared this to their ribosomal gene sequence divergences. We show that this relationship between proteome divergence and 18S divergence is lineage dependent. Unicellular lineages have especially low 18S divergences relative to their protein sequence divergences, suggesting that 18S ribosomal genes are too conservative to assess planktonic eukaryotic diversity. We provide an explanation for this lineage dependency, which suggests that most species with large effective population sizes will show far less divergence in 18S than protein coding sequences. CONCLUSIONS: There is therefore a trade-off between using genes that are easy to amplify in all species, but which by their nature are highly conserved and underestimate the true number of species, and using genes that give a better description of the number of species, but which are more difficult to amplify. We have shown that this trade-off differs between unicellular and multicellular organisms as a likely consequence of differences in effective population sizes. We anticipate that biodiversity of microbial eukaryotic species is underestimated and that numerous "cryptic species" will become

  4. Parenting practices, parents' underestimation of daughters' risks, and alcohol and sexual behaviors of urban girls.

    Science.gov (United States)

    O'Donnell, Lydia; Stueve, Ann; Duran, Richard; Myint-U, Athi; Agronick, Gail; San Doval, Alexi; Wilson-Simmons, Renée

    2008-05-01

    In urban economically distressed communities, high rates of early sexual initiation combined with alcohol use place adolescent girls at risk for myriad negative health consequences. This article reports on the extent to which parents of young teens underestimate both the risks their daughters are exposed to and the considerable influence that they have over their children's decisions and behaviors. Surveys were conducted with more than 700 sixth-grade girls and their parents, recruited from seven New York City schools serving low-income families. Bivariate and multivariate analyses examined relationships among parents' practices and perceptions of daughters' risks, girls' reports of parenting, and outcomes of girls' alcohol use, media and peer conduct, and heterosexual romantic and social behaviors that typically precede sexual intercourse. Although only four parents thought that their daughters had used alcohol, 22% of the daughters reported drinking in the past year. Approximately 5% of parents thought that daughters had hugged and kissed a boy for a long time or had "hung out" with older boys, whereas 38% of girls reported these behaviors. Parents' underestimation of risk was correlated with lower reports of positive parenting practices by daughters. In multivariate analyses, girls' reports of parental oversight, rules, and disapproval of risk are associated with all three behavioral outcomes. Adult reports of parenting practices are associated with girls' conduct and heterosexual behaviors, but not with their alcohol use. Creating greater awareness of the early onset of risk behaviors among urban adolescent girls is important for fostering positive parenting practices, which in turn may help parents to support their daughters' healthier choices.

  5. Early warning systems for the management of chronic heart failure: a systematic literature review of cost-effectiveness models.

    Science.gov (United States)

    Albuquerque De Almeida, Fernando; Al, Maiwenn; Koymans, Ron; Caliskan, Kadir; Kerstens, Ankie; Severens, Johan L

    2018-04-01

    Describing the general and methodological characteristics of decision-analytical models used in the economic evaluation of early warning systems for the management of chronic heart failure patients and performing a quality assessment of their methodological characteristics is expected to provide concise and useful insight to inform the future development of decision-analytical models in the field of heart failure management. Areas covered: The literature on decision-analytical models for the economic evaluation of early warning systems for the management of chronic heart failure patients was systematically reviewed. Nine electronic databases were searched through the combination of synonyms for heart failure and sensitive filters for cost-effectiveness and early warning systems. Expert commentary: The retrieved models show some variability with regards to their general study characteristics. Overall, they display satisfactory methodological quality, even though some points could be improved, namely on the consideration and discussion of any competing theories regarding model structure and disease progression, identification of key parameters and the use of expert opinion, and uncertainty analyses. A comprehensive definition of early warning systems and further research under this label should be pursued. To improve the transparency of economic evaluation publications, authors should make available detailed technical information regarding the published models.

  6. Composition effects on chemical durability and viscosity of nuclear waste glasses - systematic studies and structural thermodynamic models

    International Nuclear Information System (INIS)

    Feng, X.

    1988-01-01

    Two of the primary criteria for the acceptability of nuclear waste glasses are their durability, i.e. chemical resistance to aqueous attack for 10 4 to 10 5 years, and processability, which requires their viscosity at the desired melt temperature to be sufficiently low. Chapter 3 presents the results of systematic composition variation studies around the preliminary reference glass composition WV205 and an atomistic interpretation of the effects of individual oxides. Chapter 4 is concerned with modifications of the Jantzen-Plodinec hydration model which takes into account formation of complex aluminosilicate compounds in the glass. Chapter 5 is devoted to the development and validation of the structural-thermodynamic model for both durability and viscosity. This model assumes the strength of bonds between atoms to be the controlling factor in the composition dependence of these glass properties. The binding strengths are derived from the known heats of formation and the structural roles of constituent oxides. Since the coordination state of various oxides in the glass is temperature dependent and cation size has opposite effects on the two properties, the correlation between melt viscosity and rate of corrosion at low temperature is not simply linear. Chapter 6 surveys the effects of aqueous phase composition on the leach behavior of glasses. These studies provide a comprehensive view of the effects of both glass composition and leachant composition on leaching. The models developed correlate both durability and viscosity with glass composition. A major implication is that these findings can be used in the systematic optimization of the properties of complex oxide glasses

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

    Science.gov (United States)

    Hoang, Ha; Le, Quynh; Ogden, Kathryn

    2014-12-01

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

  8. SEMI-EMPIRICAL WHITE DWARF INITIAL-FINAL MASS RELATIONSHIPS: A THOROUGH ANALYSIS OF SYSTEMATIC UNCERTAINTIES DUE TO STELLAR EVOLUTION MODELS

    International Nuclear Information System (INIS)

    Salaris, Maurizio; Serenelli, Aldo; Weiss, Achim; Miller Bertolami, Marcelo

    2009-01-01

    Using the most recent results about white dwarfs (WDs) in ten open clusters, we revisit semiempirical estimates of the initial-final mass relation (IFMR) in star clusters, with emphasis on the use of stellar evolution models. We discuss the influence of these models on each step of the derivation. One intention of our work is to use consistent sets of calculations both for the isochrones and the WD cooling tracks. The second one is to derive the range of systematic errors arising from stellar evolution theory. This is achieved by using different sources for the stellar models and by varying physical assumptions and input data. We find that systematic errors, including the determination of the cluster age, are dominating the initial mass values, while observational uncertainties influence the final mass primarily. After having determined the systematic errors, the initial-final mass relation allows us finally to draw conclusions about the physics of the stellar models, in particular about convective overshooting.

  9. A systematic multiscale modeling and experimental approach to protect grain boundaries in magnesium alloys from corrosion

    Energy Technology Data Exchange (ETDEWEB)

    Horstemeyer, Mark R. [Mississippi State Univ., Mississippi State, MS (United States); Chaudhuri, Santanu [Univ. of Illinois, Urbana-Champaign, IL (United States)

    2015-09-30

    A multiscale modeling Internal State Variable (ISV) constitutive model was developed that captures the fundamental structure-property relationships. The macroscale ISV model used lower length scale simulations (Butler-Volmer and Electronics Structures results) in order to inform the ISVs at the macroscale. The chemomechanical ISV model was calibrated and validated from experiments with magnesium (Mg) alloys that were investigated under corrosive environments coupled with experimental electrochemical studies. Because the ISV chemomechanical model is physically based, it can be used for other material systems to predict corrosion behavior. As such, others can use the chemomechanical model for analyzing corrosion effects on their designs.

  10. THE SYSTEMATICS OF STRONG LENS MODELING QUANTIFIED: THE EFFECTS OF CONSTRAINT SELECTION AND REDSHIFT INFORMATION ON MAGNIFICATION, MASS, AND MULTIPLE IMAGE PREDICTABILITY

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Traci L.; Sharon, Keren, E-mail: tljohn@umich.edu [University of Michigan, Department of Astronomy, 1085 South University Avenue, Ann Arbor, MI 48109-1107 (United States)

    2016-11-20

    Until now, systematic errors in strong gravitational lens modeling have been acknowledged but have never been fully quantified. Here, we launch an investigation into the systematics induced by constraint selection. We model the simulated cluster Ares 362 times using random selections of image systems with and without spectroscopic redshifts and quantify the systematics using several diagnostics: image predictability, accuracy of model-predicted redshifts, enclosed mass, and magnification. We find that for models with >15 image systems, the image plane rms does not decrease significantly when more systems are added; however, the rms values quoted in the literature may be misleading as to the ability of a model to predict new multiple images. The mass is well constrained near the Einstein radius in all cases, and systematic error drops to <2% for models using >10 image systems. Magnification errors are smallest along the straight portions of the critical curve, and the value of the magnification is systematically lower near curved portions. For >15 systems, the systematic error on magnification is ∼2%. We report no trend in magnification error with the fraction of spectroscopic image systems when selecting constraints at random; however, when using the same selection of constraints, increasing this fraction up to ∼0.5 will increase model accuracy. The results suggest that the selection of constraints, rather than quantity alone, determines the accuracy of the magnification. We note that spectroscopic follow-up of at least a few image systems is crucial because models without any spectroscopic redshifts are inaccurate across all of our diagnostics.

  11. Effects of waveform model systematics on the interpretation of GW150914

    NARCIS (Netherlands)

    Abbott, B. P.; Abbott, R.; Abbott, T. D.; Abernathy, M. R.; Acernese, F.; Ackley, K.; Adams, C.; Phythian-Adams, A.T.; Addesso, P.; Adhikari, R. X.; Adya, V. B.; Affeldt, C.; Agathos, M.; Agatsuma, K.; Aggarwal, N.T.; Aguiar, O. D.; Aiello, L.; Ain, A.; Ajith, P.; Allen, B.; Allocca, A.; Altin, P. A.; Ananyeva, A.; Anderson, S. B.; Anderson, W. G.; Appert, S.; Arai, K.; Araya, M. C.; Areeda, J. S.; Arnaud, N.; Arun, K. G.; Ascenzi, S.; Ashton, G.; Ast, M.; Aston, S. M.; Astone, P.; Aufmuth, P.; Aulbert, C.; Avila-Alvarez, A.; Babak, S.; Bacon, P.; Bader, M. K.M.; Baker, P. T.; Baldaccini, F.; Ballardin, G.; Ballmer, S. W.; Barayoga, J. C.; Barclay, S. E.; Barish, B. C.; Barker, R.D.; Barone, F.; Barr, B.; Barsotti, L.; Barsuglia, M.; Barta, D.; Bartlett, J.; Bartos, I.; Bassiri, R.; Basti, A.; Batch, J. C.; Baune, C.; Bavigadda, V.; Bazzan, M.; Beer, C.; Bejger, M.; Belahcene, I.; Belgin, M.; Bell, A. S.; Berger, B. K.; Bergmann, G.; Berry, C. P. L.; Bersanetti, D.; Bertolini, A.; Betzwieser, J.; Bhagwat, S.; Bhandare, R.; Bilenko, I. A.; Billingsley, G.; Billman, C. R.; Birch, M.J.; Birney, R.; Birnholtz, O.; Biscans, S.; Bisht, A.; Bitossi, M.; Biwer, C.; Bizouard, M. A.; Blackburn, J. K.; Blackman, J.; Blair, C. D.; Blair, D. G.; Blair, R. M.; Bloemen, A.L.S.; Bock, O.; Boer, M.; Bogaert, J.G.; Bohe, A.; Bondu, F.; Bonnand, R.; Boom, B. A.; Bork, R.; Boschi, V.; Bose, S.; Bouffanais, Y.; Bozzi, A.; Bradaschia, C.; Brady, P. R.; Braginsky, V. B.; Branchesi, M.; Brau, J. E.; Briant, T.; Brillet, A.; Brinkmann, M.; Brisson, V.; Brockill, P.; Broida, J. E.; Brooks, A. F.; Brown, A.D.; Brown, D.; Brown, N. M.; Brunett, S.; Buchanan, C. C.; Buikema, A.; Bulik, T.; Bulten, H. J.; Buonanno, A.; Buskulic, D.; Buy, C.; Byer, R. L.; Cabero, M.; Cadonati, L.; Cagnoli, G.; Cahillane, C.; Calderón Bustillo, J.; Callister, T. A.; Calloni, E.; Camp, J. B.; Cannon, K. C.; Cao, H.; Cao, J.; Capano, C. D.; Capocasa, E.; Carbognani, F.; Caride, S.; Casanueva Diaz, J.; Casentini, C.; Caudill, S.; Cavaglià, M.; Cavalier, F.; Cavalieri, R.; Cella, G.; Cepeda, C. B.; Cerboni Baiardi, L.; Cerretani, G.; Cesarini, E.; Chamberlin, S. J.; Chan, M.; Chao, D. S.; Charlton, P.; Chassande-Mottin, E.; Cheeseboro, B. D.; Chen, H. Y.; Chen, Y; Cheng, H. -P.; Chincarini, A.; Chiummo, A.; Chmiel, T.; Cho, H. S.; Cho, M.; Chow, J. H.; Christensen, N.; Chu, Qian; Chua, A. J. K.; Chua, S. S. Y.; Chung, E.S.; Ciani, G.; Clara, F.; Clark, J. A.; Cleva, F.; Cocchieri, C.; Coccia, E.; Cohadon, P. -F.; Colla, A.; Collette, C. G.; Cominsky, L.; Constancio, M., Jr.; Conti, L.; Cooper, S. J.; Corbitt, T. R.; Cornish, N.; Corsi, A.; Cortese, S.; Costa, A.C.; Coughlin, M. W.; Coughlin, S. B.; Coulon, J. -P.; Countryman, S. T.; Couvares, P.; Covas, P. B.; Cowan, E. E.; Coward, D. M.; Cowart, M. J.; Coyne, D. C.; Coyne, R.; Creighton, J. D. E.; Creighton, T. D.; Cripe, J.; Crowder, S. G.; Cullen, T. J.; Cumming, A.; Cunningham, Laura; Cuoco, E.; Dal Canton, T.; Danilishin, S. L.; D'Antonio, S.; Danzmann, K.; Dasgupta, A.; Da Silva Costa, C. F.; Dattilo, V.; Dave, I.; Davier, M.; Davies, G. S.; Davis, D.; Daw, E. J.; Day, B.; Day, R.; De, S.; Debra, D.; Debreczeni, G.; Degallaix, J.; De laurentis, M.; Deléglise, S.; Del Pozzo, W.; Denker, T.; Dent, T.; Dergachev, V.A.; Rosa, R.; DeRosa, R. T.; DeSalvo, R.; Devenson, J.; Devine, R. C.; Dhurandhar, S.; Díaz, M. C.; Di Fiore, L.; Giovanni, M. Di; Di Girolamo, T.; Di Lieto, A.; Di Pace, S.; Di Palma, I.; Di Virgilio, A.; Doctor, Z.; Dolique, V.; Donovan, F.; Dooley, K. L.; Doravari, S.; Dorrington, I.; Douglas, R.; Dovale Álvarez, M.; Downes, T. P.; Drago, M.; Drever, R. W. P.; Driggers, J. C.; Du, Z.; Ducrot, M.; Dwyer, S. E.; Edo, T. B.; Edwards, M. C.; Effler, A.; Eggenstein, H. -B.; Ehrens, P.; Eichholz, J.; Eikenberry, S. S.; Eisenstein, R. A.; Essick, R. C.; Etienne, Z.; Etzel, T.; Evans, T. M.; Evans, T. M.; Everett, R.; Factourovich, M.; Fafone, V.; Fair, H.; Fairhurst, S.; Fan, X.M.; Farinon, S.; Farr, B.; Farr, W. M.; Fauchon-Jones, E. J.; Favata, M.; Fays, M.; Fehrmann, H.; Fejer, M. M.; Fernández Galiana, A.; Ferrante, I.; Ferreira, E. C.; Ferrini, F.; Fidecaro, F.; Fiori, I.; Fiorucci, D.; Fisher, R. P.; Flaminio, R.; Fletcher, M; Fong, H.; Forsyth, S. S.; Fournier, J. -D.; Frasca, S.; Frasconi, F.; Frei, Z.; Freise, A.; Frey, R.; Frey, V.; Fries, E. M.; Fritschel, P.; Frolov, V. V.; Fulda, P.; Fyffe, M.; Gabbard, H.; Gadre, B. U.; Gaebel, S. M.; Gair, J. R.; Gammaitoni, L.; Gaonkar, S. G.; Garufi, F.; Gaur, G.; Gayathri, V.; Gehrels, N.; Gemme, G.; Genin, E.; Gennai, A.; George, J.; Gergely, L.; Germain, V.; Ghonge, S.; Ghosh, Abhirup; Ghosh, Archisman; Ghosh, S.; Giaime, J. A.; Giardina, K. D.; Giazotto, A.; Gill, K.P.; Glaefke, A.; Goetz, E.; Goetz, R.; Gondan, L.; González, G.; Gonzalez Castro, J. M.; Gopakumar, A.; Gorodetsky, M. L.; Gossan, S. E.; Lee-Gosselin, M.; Gouaty, R.; Grado, A.; Graef, C.; Granata, M.; Grant, A.; Gras, S.; Gray, C.M.; Greco, G.; Green, A. C.; Groot, P.; Grote, H.; Grunewald, S.; Guidi, G. M.; Guo, X.; Gupta, A.; Gupta, M. K.; Gushwa, K. E.; Gustafson, E. K.; Gustafson, R.; Hacker, J. J.; Buffoni-Hall, R.; Hall, E. D.; Hammond, G.L.; Haney, M.; Hanke, M. M.; Hanks, J.; Hanna, C.; Hannam, M. D.; Hanson, P.J.; Hardwick, T.; Harms, J.; Harry, G. M.; Harry, I. W.; Hart, M. J.; Hartman, M. T.; Haster, C. -J.; Haughian, K.; Healy, J.; Heidmann, A.; Heintze, M. C.; Heitmann, H.; Hello, P.; Hemming, G.; Hendry, M.; Heng, I. S.; Hennig, J.; Henry, J.A.; Heptonstall, A. W.; Heurs, M.; Hild, S.; Hoak, D.; Hofman, D.; Holt, K.; Holz, D. E.; Hopkins, P.; Hough, J.; Houston, E. A.; Howell, E. J.; Hu, Y. M.; Huerta, E. A.; Huet, D.; Hughey, B.; Husa, S.; Huttner, S. H.; Huynh-Dinh, T.; Indik, N.; Ingram, D. R.; Inta, R.; Isa, H. N.; Isac, J. -M.; Isi, M.; Isogai, T.; Iyer, B. R.; Izumi, K.; Jacqmin, T.; Jani, K.; Jaranowski, P.; Jawahar, S.; Jiménez-Forteza, F.; Johnson, W.; Jones, I.D.; Jones, R.; Jonker, R. J.G.; Ju, L.; Junker, J.; Kalaghatgi, C. V.; Kalogera, V.; Kandhasamy, S.; Kang, G.H.; Kanner, J. B.; Karki, S.; Karvinen, K. S.; Kasprzack, M.; Katsavounidis, E.; Katzman, W.; Kaufer, S.; Kaur, T.; Kawabe, K.; Kéfélian, F.; Keitel, D.; Kelley, D. B.; Kennedy, R.E.; Key, J. S.; Khalili, F. Y.; Khan, I.; Khan., S.; Khan, Z.; Khazanov, E. A.; Kijbunchoo, N.; Kim, Chunglee; Kim, J. C.; Kim, Whansun; Kim, W.; Kim, Y.M.; Kimbrell, S. J.; King, E. J.; King, P. J.; Kirchhoff, R.; Kissel, J. S.; Klein, B.; Kleybolte, L.; Klimenko, S.; Koch, P.; Koehlenbeck, S. M.; Koley, S.; Kondrashov, V.; Kontos, A.; Korobko, M.; Korth, W. Z.; Kowalska, I.; Kozak, D. B.; Krämer, C.; Kringel, V.; Krishnan, B.; Królak, A.; Kuehn, G.; Kumar, P.; Kumar, R.; Kuo, L.; Kutynia, A.; Lackey, B. D.; Landry, M.; Lang, R. N.; Lange, J.; Lantz, B.; Lanza, R. K.; Lartaux-Vollard, A.; Lasky, P. D.; Laxen, M.; Lazzarini, A.; Lazzaro, C.; Leaci, P.; Leavey, S.; Lebigot, E. O.; Lee, C.H.; Lee, K.H.; Lee, M.H.; Lee, K.; Lehmann, J.; Lenon, A.; Leonardi, M.; Leong, J. R.; Leroy, N.; Letendre, N.; Levin, Y.; Li, T. G.F.; Libson, A.; Littenberg, T. B.; Liu, J.; Lockerbie, N. A.; Lombardi, A. L.; London, L. T.; Lord, J. E.; Lorenzini, M.; Loriette, V.; Lormand, M.; Losurdo, G.; Lough, J. D.; Lovelace, G.; Lück, H.; Lundgren, A. P.; Lynch, R.; Ma, Y.; Macfoy, S.; Machenschalk, B.; MacInnis, M.; Macleod, D. M.; Magaña-Sandoval, F.; Majorana, E.; Maksimovic, I.; Malvezzi, V.; Man, N.; Mandic, V.; Mangano, V.; Mansell, G. L.; Manske, M.; Mantovani, M.; Marchesoni, F.; Marion, F.; Márka, S.; Márka, Z.; Markosyan, A. S.; Maros, E.; Martelli, F.; Martellini, L.; Martin, I. W.; Martynov, D. V.; Mason, K.; Masserot, A.; Massinger, T. J.; Masso-Reid, M.; Mastrogiovanni, S.; Matichard, F.; Matone, L.; Mavalvala, N.; Mazumder, N.; McCarthy, R.; McClelland, D. E.; McCormick, S.; McGrath Hoareau, C.; McGuire, S. C.; McIntyre, G.; McIver, J.; McManus, D. J.; McRae, T.; McWilliams, S. T.; Meacher, D.; Meadors, G. D.; Meidam, J.; Melatos, A.; Mendell, G.; Mendoza-Gandara, D.; Mercer, R. A.; Merilh, E. L.; Merzougui, M.; Meshkov, S.; Messenger, C.; Messick, C.; Metzdorff, R.; Meyers, P. M.; Mezzani, F.; Miao, H.; Michel, C.; Middleton, H.; Mikhailov, E. E.; Milano, L.; Miller, A. L.; Miller, A. L.; Miller, B.; Miller, J.; Millhouse, M.; Minenkov, Y.; Ming, J.; Mirshekari, S.; Mishra, C.; Mitra, S.; Mitrofanov, V. P.; Mitselmakher, G.; Mittleman, R.; Moggi, A.; Mohan, M.; Mohapatra, S. R. P.; Montani, M.; Moore, B.C.; Moore, Brian C J; Moraru, D.; Gutierrez Moreno, M.; Morriss, S. R.; Mours, B.; Mow-Lowry, C. M.; Mueller, G.; Muir, A. W.; Mukherjee, Arunava; Mukherjee, S.D.; Mukherjee, S.; Mukund, N.; Mullavey, A.; Munch, J.; Muniz, E. A. M.; Murray, P.G.; Mytidis, A.; Napier, K.; Nardecchia, I.; Naticchioni, L.; Nelemans, G.; Nelson, T. J. N.; Gutierrez-Neri, M.; Nery, M.; Neunzert, A.; Newport, J. M.; Newton-Howes, G.; Nguyen, T. T.; Nielsen, A. B.; Nissanke, S.; Nitz, A.; Noack, A.; Nocera, F.; Nolting, D.; Normandin, M. E. N.; Nuttall, L. K.; Oberling, J.; Ochsner, E.; Oelker, E.; Ogin, G. H.; Oh, J.; Oh, S. H.; Ohme, F.; Oliver, M. B.; Oppermann, P.; Oram, Richard J.; O'Reilly, B.; O'Shaughnessy, R.; Ottaway, D. J.; Overmier, H.; Owen, B. J.; Pace, A. E.; Page, J.; Pai, A.; Pai, S. A.; Palamos, J. R.; Palashov, O.; Palomba, C.; Pal-Singh, A.; Pan, H.; Pankow, C.; Pannarale, F.; Pant, B. C.; Paoletti, F.; Paoli, A.; Papa, M. A.; Paris, H. R.; Parker, W.S; Pascucci, D.; Pasqualetti, A.; Passaquieti, R.; Passuello, D.; Patricelli, B.; Pearlstone, B. L.; Pedraza, M.; Pedurand, R.; Pekowsky, L.; Pele, A.; Penn, S.; Castro-Perez, J.; Perreca, A.; Perri, L. M.; Pfeiffer, H. P.; Phelps, M.; Piccinni, O. J.; Pichot, M.; Piergiovanni, F.; Pierro, V.; Pillant, G.; Pinard, L.; Pinto, I. M.; Pitkin, M.; Poe, M.; Poggiani, R.; Popolizio, P.; Post, A.; Powell, J.; Prasad, J.; Pratt, J. W. W.; Predoi, V.; Prestegard, T.; Prijatelj, M.; Principe, M.; Privitera, S.; Prodi, G. A.; Prokhorov, L. G.; Puncken, O.; Punturo, M.; Puppo, P.; Pürrer, M.; Qi, H.; Qin, J.; Qiu, S.; Quetschke, V.; Quintero, E. A.; Quitzow-James, R.; Raab, F. J.; Rabeling, D. S.; Radkins, H.; Raffai, P.; Raja, S.; Rajan, C.; Rakhmanov, M.; Rapagnani, P.; Raymond, V.; Razzano, M.; Re, V.; Read, J.; Regimbau, T.; Rei, L.; Reid, S.; Reitze, D. H.; Rew, H.; Reyes, S. D.; Rhoades, E.; Ricci, F.; Riles, K.; Rizzo, D.M.; Robertson, N. A.; Robie, R.; Robinet, F.; Rocchi, A.; Rolland, L.; Rollins, J. G.; Roma, V. J.; Romano, J. D.; Romano, R.; Romie, J. H.; Rosińska, D.; Rowan, S.; Rüdiger, A.; Ruggi, P.; Ryan, K.A.; Sachdev, Perminder S; Sadecki, T.; Sadeghian, L.; Sakellariadou, M.; Salconi, L.; Saleem, M.; Salemi, F.; Samajdar, A.; Sammut, L.; Sampson, L. M.; Sanchez, E. J.; Sandberg, V.; Sanders, J. R.; Sassolas, B.; Sathyaprakash, B. S.; Saulson, P. R.; Sauter, O.; Savage, R. L.; Sawadsky, A.; Schale, P.; Scheuer, J.; Schmidt, E.; Schmidt, J; Schmidt, P.; Schnabel, R.B.; Schofield, R. M. S.; Schönbeck, A.; Schreiber, K.E.C.; Schuette, D.; Schutz, B. F.; Schwalbe, S. G.; Scott, J.; Scott, M.S.; Sellers, D.; Sengupta, A. S.; Sentenac, D.; Sequino, V.; Sergeev, A.; Setyawati, Y.; Shaddock, D. A.; Shaffer, T. J.; Shahriar, M. S.; Shapiro, B.; Shawhan, P.; Sheperd, A.; Shoemaker, D. H.; Shoemaker, D. M.; Siellez, K.; Siemens, X.; Sieniawska, M.; Sigg, D.; Silva, António Dias da; Singer, A; Singer, L. P.; Singh, A.; Singh, R.; Singhal, A.; Sintes, A. M.; Slagmolen, B. J. J.; Smith, B.; Smith, R. J. E.; Smith, R. J. E.; Son, E. J.; Sorazu, B.; Sorrentino, F.; Souradeep, T.; Spencer, A. P.; Srivastava, A. K.; Staley, A.; Steinke, M.; Steinlechner, J.; Steinlechner, S.; Steinmeyer, D.; Stephens, B. C.; Stevenson-Moore, P.; Stone, J.R.; Strain, K. A.; Straniero, N.; Stratta, G.; Strigin, S. E.; Sturani, R.; Stuver, A. L.; Summerscales, T. Z.; Sun, L.; Sunil, S.; Sutton, P. J.; Swinkels, B. L.; Szczepańczyk, M. J.; Tacca, M.D.; Talukder, D.; Tanner, D. B.; Tápai, M.; Taracchini, A.; Taylor, W.R.; Theeg, T.; Thomas, E. G.; Thomas, M.; Thomas, P.; Thorne, K. A.; Thrane, E.; Tippens, T.; Tiwari, S.; Tiwari, V.; Tokmakov, K. V.; Toland, K.; Tomlinson, C.; Tonelli, M.; Tornasi, Z.; Torrie, C. I.; Töyrä, D.; Travasso, F.; Traylor, G.; Trifir, D.; Trinastic, J.; Tringali, M. C.; Trozzo, L.; Tse, M.; Tso, R.; Turconi, M.; Tuyenbayev, D.; Ugolini, D.; Unnikrishnan, C. S.; Urban, A. L.; Usman, S. A.; Vahlbruch, H.; Vajente, G.; Valdes, G.; Van Bakel, N.; Van Beuzekom, Martin; Van Den Brand, J. F.J.; Van Den Broeck, C.F.F.; Vander-Hyde, D. C.; van der Schaaf, L.; van Heijningen, J. V.; van Veggel, A. A.; Vardaro, M.; Varma, V.; Vass, S.; Vasúth, M.; Vecchio, A.; Vedovato, G.; Veitch, J.; Veitch, P.J.; Venkateswara, K.; Venugopalan, G.; Verkindt, D.; Vetrano, F.; Viceré, A.; Viets, A. D.; Vinciguerra, S.; Vine, D. J.; Vinet, J. -Y.; Vitale, S.; Vo, T.; Vocca, H.; Vorvick, C.; Voss, D. V.; Vousden, W. D.; Vyatchanin, S. P.; Wade, A. R.; Wade, L. E.; Wade, MT; Walker, M.; Wallace, L.; Walsh, S.; Wang, G.; Wang, H.; Wang, M.; Wang, Y.; Ward, R. L.; Warner, J.; Was, M.; Watchi, J.; Weaver, B.; Wei, L. -W.; Weinert, M.; Weinstein, A. J.; Weiss, R.; Wen, L.M.; Weßels, P.; Westphal, T.; Wette, K.; Whelan, J. T.; Whiting, B. F.; Whittle, C.; Williams, D.; Williams, D.R.; Williamson, A. R.; Willis, J. L.; Willke, B.; Wimmer, M. H.; Winkler, W.; Wipf, C. C.; Wittel, H.; Woan, G.; Woehler, J.; Worden, J.; Wright, J.L.; Wu, D.S.; Wu, G.; Yam, W.; Yamamoto, H.; Yancey, C. C.; Yap, M. J.; Yu, Hang; Yu, Haocun; Yvert, M.; Zadrożny, A.; Zangrando, L.; Zanolin, M.; Zendri, J. -P.; Zevin, M.; Zhang, L.; Zhang, M.; Zhang, T.; Zhang, Y.; Zhao, C.; Zhou, M.; Zhou, Z.; Zhu, S.J.; Zhu, X. J.; Zucker, M. E.; Zweizig, J.; Boyle, M.; Chu, I.W.T.; Hemberger, D.; Hinder, I.; Kidder, L. E.; Ossokine, S.; Scheel, M.; Szilagyi, B.; Teukolsky, S.; Vano-Vinuales, A.

    2017-01-01

    Parameter estimates of GW150914 were obtained using Bayesian inference, based on three semi-analytic waveform models for binary black hole coalescences. These waveform models differ from each other in their treatment of black hole spins, and all three models make some simplifying assumptions,

  12. A Systematic Review of Studies on Leadership Models in Educational Research from 1980 to 2014

    Science.gov (United States)

    Gumus, Sedat; Bellibas, Mehmet Sukru; Esen, Murat; Gumus, Emine

    2018-01-01

    The purpose of this study is to reveal the extent to which different leadership models in education are studied, including the change in the trends of research on each model over time, the most prominent scholars working on each model, and the countries in which the articles are based. The analysis of the related literature was conducted by first…

  13. Diagnostic models of the pre-test probability of stable coronary artery disease: A systematic review

    Directory of Open Access Journals (Sweden)

    Ting He

    Full Text Available A comprehensive search of PubMed and Embase was performed in January 2015 to examine the available literature on validated diagnostic models of the pre-test probability of stable coronary artery disease and to describe the characteristics of the models. Studies that were designed to develop and validate diagnostic models of pre-test probability for stable coronary artery disease were included. Data regarding baseline patient characteristics, procedural characteristics, modeling methods, metrics of model performance, risk of bias, and clinical usefulness were extracted. Ten studies involving the development of 12 models and two studies focusing on external validation were identified. Seven models were validated internally, and seven models were validated externally. Discrimination varied between studies that were validated internally (C statistic 0.66-0.81 and externally (0.49-0.87. Only one study presented reclassification indices. The majority of better performing models included sex, age, symptoms, diabetes, smoking, and hyperlipidemia as variables. Only two diagnostic models evaluated the effects on clinical decision making processes or patient outcomes. Most diagnostic models of the pre-test probability of stable coronary artery disease have had modest success, and very few present data regarding the effects of these models on clinical decision making processes or patient outcomes.

  14. Prediction Models for Prolonged Intensive Care Unit Stay after Cardiac Surgery: Systematic Review and Validation Study

    NARCIS (Netherlands)

    Linda Peelen; Karel Moons; Cor Kalkman; Prof. Dr. Marieke J. Schuurmans; Roelof G.A. Ettema; Arno Nierich

    2010-01-01

    Several models have been developed to predict prolonged stay in the intensive care unit (ICU) after cardiac surgery. However, no extensive quantitative validation of these models has yet been conducted. This study sought to identify and validate existing prediction models for prolonged ICU length of

  15. Population-level impact, herd immunity, and elimination after human papillomavirus vaccination: a systematic review and meta-analysis of predictions from transmission-dynamic models.

    NARCIS (Netherlands)

    Brisson, Marc; Bénard, Élodie; Drolet, Mélanie; Bogaards, Johannes A; Baussano, Iacopo; Vänskä, Simopekka; Jit, Mark; Boily, Marie-Claude; Smith, Megan A; Berkhof, Johannes; Canfell, Karen; Chesson, Harrell W; Burger, Emily A; Choi, Yoon H; De Blasio, Birgitte Freiesleben; De Vlas, Sake J; Guzzetta, Giorgio; Hontelez, Jan A C; Horn, Johannes; Jepsen, Martin R; Kim, Jane J; Lazzarato, Fulvio; Matthijsse, Suzette M; Mikolajczyk, Rafael; Pavelyev, Andrew; Pillsbury, Matthew; Shafer, Leigh Anne; Tully, Stephen P; Turner, Hugo C; Usher, Cara; Walsh, Cathal

    2016-01-01

    Modelling studies have been widely used to inform human papillomavirus (HPV) vaccination policy decisions; however, many models exist and it is not known whether they produce consistent predictions of population-level effectiveness and herd effects. We did a systematic review and meta-analysis of

  16. Using a Systematic Conceptual Model for a Process Evaluation of a Middle School Obesity Risk-Reduction Nutrition Curriculum Intervention: "Choice, Control & Change"

    Science.gov (United States)

    Lee, Heewon; Contento, Isobel R.; Koch, Pamela

    2013-01-01

    Objective: To use and review a conceptual model of process evaluation and to examine the implementation of a nutrition education curriculum, "Choice, Control & Change", designed to promote dietary and physical activity behaviors that reduce obesity risk. Design: A process evaluation study based on a systematic conceptual model. Setting: Five…

  17. Evidence used in model-based economic evaluations for evaluating pharmacogenetic and pharmacogenomic tests: a systematic review protocol.

    Science.gov (United States)

    Peters, Jaime L; Cooper, Chris; Buchanan, James

    2015-11-11

    Decision models can be used to conduct economic evaluations of new pharmacogenetic and pharmacogenomic tests to ensure they offer value for money to healthcare systems. These models require a great deal of evidence, yet research suggests the evidence used is diverse and of uncertain quality. By conducting a systematic review, we aim to investigate the test-related evidence used to inform decision models developed for the economic evaluation of genetic tests. We will search electronic databases including MEDLINE, EMBASE and NHS EEDs to identify model-based economic evaluations of pharmacogenetic and pharmacogenomic tests. The search will not be limited by language or date. Title and abstract screening will be conducted independently by 2 reviewers, with screening of full texts and data extraction conducted by 1 reviewer, and checked by another. Characteristics of the decision problem, the decision model and the test evidence used to inform the model will be extracted. Specifically, we will identify the reported evidence sources for the test-related evidence used, describe the study design and how the evidence was identified. A checklist developed specifically for decision analytic models will be used to critically appraise the models described in these studies. Variations in the test evidence used in the decision models will be explored across the included studies, and we will identify gaps in the evidence in terms of both quantity and quality. The findings of this work will be disseminated via a peer-reviewed journal publication and at national and international conferences. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  18. Neuroprotective properties of curcumin in toxin-base animal models of Parkinson's disease: a systematic experiment literatures review.

    Science.gov (United States)

    Wang, Xin-Shi; Zhang, Zeng-Rui; Zhang, Man-Man; Sun, Miao-Xuan; Wang, Wen-Wen; Xie, Cheng-Long

    2017-08-17

    Curcumin (diferuloylmethane), a polyphenol extracted from the plant Curcuma longa, is widely used in Southeast Asia, China and India in food preparation and for medicinal purposes. Meanwhile, the neuroprotective actions of curcumin have been documented for experimental therapy in Parkinson's disease (PD). In this study, we used a systematic review to comprehensively assess the efficacy of curcumin in experimental PD. Using electronic and manual search for the literatures, we identified studies describing the efficacy of curcumin in animal models of PD. We identified 13 studies with a total of 298 animals describing the efficacy of curcumin in animal models of PD. The methodological quality of all preclinical trials is ranged from 2 to 5. The majority of the experiment studies demonstrated that curcumin was more significantly neuroprotection effective than control groups for treating PD. Among them, five studies indicated that curcumin had an anti-inflammatory effect in the PD animal models (p curcumin, by which it protected substantia nigra neurons and improved striatal dopamine levels. Furthermore, two studies in this review displayed that curcumin treatment was also effective in reducing neuronal apoptosis and improving functional outcome in animal models of PD. Most of the preclinical studies demonstrated the positive findings while one study reported that curcumin had no beneficial effects against Mn-induced disruption of hippocampal metal and neurotransmitter homeostasis. The results demonstrated a marked efficacy of curcumin in experimental model of PD, suggesting curcumin probably a candidate neuroprotective drug for human PD patients.

  19. A systematic review of the application of Wilson and Cleary health-related quality of life model in chronic diseases.

    Science.gov (United States)

    Ojelabi, Adedokun Oluwafemi; Graham, Yitka; Haighton, Catherine; Ling, Jonathan

    2017-12-11

    A conceptual model approach to clarify the elements of health-related quality of life (HRQL), their determinants and causal pathways is needed to aid researchers, health practitioners and policy makers in their bid to improve HRQL outcomes in patients. The aim of this systematic review was to appraise empirical evidence on the performance of the Wilson and Cleary Model of HRQL. We conducted a search of MEDLINE, Science Direct, PsyARTICLES and CINAHL databases to identify articles that used Wilson and Cleary model to examine HRQL in chronic diseases. A narrative synthesis was employed in the review of the articles. Evidence supports linkages between adjacent concepts and between non-adjacent concepts of the Wilson and Cleary model indicating that in practice there is a need to examine relationships among constructs - or to consider interventions in terms of - both with and without mediators. Symptoms status has the highest magnitude of relative impact on health-related quality of life. The Wilson and Cleary model demonstrated good features suitable for evaluating health-related quality of life in chronic diseases.

  20. Scientific Message Translation and the Heuristic Systematic Model: Insights for Designing Educational Messages About Progesterone and Breast Cancer Risks.

    Science.gov (United States)

    Hitt, Rose; Perrault, Evan; Smith, Sandi; Keating, David M; Nazione, Samantha; Silk, Kami; Russell, Jessica

    2016-06-01

    Results of ongoing scientific research on environmental determinants of breast cancer are not typically presented to the public in ways they can easily understand and use to take preventive actions. In this study, results of scientific studies on progesterone exposure as a risk factor for breast cancer were translated into high and low literacy level messages. Using the heuristic systematic model, this study examined how ability, motivation, and message processing (heuristic and systematic) influenced perceptions of risk beliefs and negative attitudes about progesterone exposure among women who read the translated scientific messages. Among the 1254 participants, those given the higher literacy level message had greater perceptions of risk about progesterone. Heuristic message cues of source credibility and perceived message quality, as well as motivation, also predicted risk beliefs. Finally, risk beliefs were a strong predictor of negative attitudes about exposure to progesterone. The results can help improve health education message design in terms of practitioners having better knowledge of message features that are the most persuasive to the target audiences on this topic.

  1. Effective interventions for cumulative trauma disorders of the upper extremity in computer users: practice models based on systematic review.

    Science.gov (United States)

    Goodman, Glenn; Kovach, Laura; Fisher, April; Elsesser, Elizabeth; Bobinski, Daniel; Hansen, Jessica

    2012-01-01

    A systematic review of over 4600 abstracts was performed to address the effectiveness of the current cumulative trauma disorder (CTD) interventions focused on the upper extremities of computer users. The researchers were the study participants. They included one Professor of Occupational Therapy and five Masters of Occupational Therapy Students from a Midwestern University. The Professor of Occupational Therapy has been practicing for 29 years. The researchers employed stringent inclusion criteria for this review based on similar systematic review papers. Criteria for high quality qualitative research were incorporated to include studies other than randomized-controlled trials. This approach considered knowledge gained from specific interventions that were studied in greater detail with fewer clients. The results of this study identified 25 articles that met the inclusion criteria. Further review ranked the selected articles into high, medium, or low quality based on criteria adapted from other studies. The highest levels of evidence were found for education and training in ergonomics, forearm supports, ergonomic keyboards, ergonomic mice, and exercise/rest breaks. Two models of practice were created from this review to assist occupational therapists or other professionals with intervention strategies for computer users with CTDs.

  2. Global CO2 flux inversions from remote-sensing data with systematic errors using hierarchical statistical models

    Science.gov (United States)

    Zammit-Mangion, Andrew; Stavert, Ann; Rigby, Matthew; Ganesan, Anita; Rayner, Peter; Cressie, Noel

    2017-04-01

    The Orbiting Carbon Observatory-2 (OCO-2) satellite was launched on 2 July 2014, and it has been a source of atmospheric CO2 data since September 2014. The OCO-2 dataset contains a number of variables, but the one of most interest for flux inversion has been the column-averaged dry-air mole fraction (in units of ppm). These global level-2 data offer the possibility of inferring CO2 fluxes at Earth's surface and tracking those fluxes over time. However, as well as having a component of random error, the OCO-2 data have a component of systematic error that is dependent on the instrument's mode, namely land nadir, land glint, and ocean glint. Our statistical approach to CO2-flux inversion starts with constructing a statistical model for the random and systematic errors with parameters that can be estimated from the OCO-2 data and possibly in situ sources from flasks, towers, and the Total Column Carbon Observing Network (TCCON). Dimension reduction of the flux field is achieved through the use of physical basis functions, while temporal evolution of the flux is captured by modelling the basis-function coefficients as a vector autoregressive process. For computational efficiency, flux inversion uses only three months of sensitivities of mole fraction to changes in flux, computed using MOZART; any residual variation is captured through the modelling of a stochastic process that varies smoothly as a function of latitude. The second stage of our statistical approach is to simulate from the posterior distribution of the basis-function coefficients and all unknown parameters given the data using a fully Bayesian Markov chain Monte Carlo (MCMC) algorithm. Estimates and posterior variances of the flux field can then be obtained straightforwardly from this distribution. Our statistical approach is different than others, as it simultaneously makes inference (and quantifies uncertainty) on both the error components' parameters and the CO2 fluxes. We compare it to more classical

  3. Efficacy and safety of regenerative cell therapy for pulmonary arterial hypertension in animal models: a preclinical systematic review protocol.

    Science.gov (United States)

    Suen, Colin M; Zhai, Alex; Lalu, Manoj M; Welsh, Christopher; Levac, Brendan M; Fergusson, Dean; McIntyre, Lauralyn; Stewart, Duncan J

    2016-05-25

    Pulmonary arterial hypertension (PAH) is a rare disease (15 cases per million) that is characterized by widespread loss of the pulmonary microcirculation and elevated pulmonary vascular resistance leading to pathological right ventricular remodeling and ultimately right heart failure. Regenerative cell therapies (i.e., therapies involving cells with stem or progenitor-like properties) could potentially restore the effective lung microcirculation and provide a curative therapy for PAH. Preclinical evidence suggests that regenerative cell therapy using endothelial progenitor cells or mesenchymal stem cells may be beneficial in the treatment of PAH. These findings have led to the completion of a small number of human clinical trials, albeit with modest effect compared to animal studies. The objective of this systematic review is to compare the efficacy and safety of regenerative cell therapies in preclinical models of PAH as well as assess study quality to inform future clinical studies. We will include preclinical studies of PAH in which a regenerative cell type was administered and outcomes compared to a disease control. The primary outcome will be pulmonary hemodynamics as assessed by measurement of right ventricular systolic pressure and/or mean pulmonary arterial pressure. Secondary outcomes will include mortality, survival, right ventricular remodeling, pulmonary vascular resistance, cardiac output, cardiac index, pulmonary acceleration time, tricuspid annular systolic excursion, and right ventricular wall thickness. Electronic searches of MEDLINE and EMBASE databases will be constructed and reviewed by the Peer Review of Electronic Search Strategies (PRESS) process. Search results will be screened independently in duplicate. Data from eligible studies will be extracted, pooled, and analyzed using random effects models. Risk of bias will be assessed using the SYstematic Review Centre for Laboratory animal Experimentation (SYRCLE) risk of bias tool, and

  4. Systematic validation of non-equilibrium thermochemical models using Bayesian inference

    KAUST Repository

    Miki, Kenji

    2015-10-01

    © 2015 Elsevier Inc. The validation process proposed by Babuška et al. [1] is applied to thermochemical models describing post-shock flow conditions. In this validation approach, experimental data is involved only in the calibration of the models, and the decision process is based on quantities of interest (QoIs) predicted on scenarios that are not necessarily amenable experimentally. Moreover, uncertainties present in the experimental data, as well as those resulting from an incomplete physical model description, are propagated to the QoIs. We investigate four commonly used thermochemical models: a one-temperature model (which assumes thermal equilibrium among all inner modes), and two-temperature models developed by Macheret et al. [2], Marrone and Treanor [3], and Park [4]. Up to 16 uncertain parameters are estimated using Bayesian updating based on the latest absolute volumetric radiance data collected at the Electric Arc Shock Tube (EAST) installed inside the NASA Ames Research Center. Following the solution of the inverse problems, the forward problems are solved in order to predict the radiative heat flux, QoI, and examine the validity of these models. Our results show that all four models are invalid, but for different reasons: the one-temperature model simply fails to reproduce the data while the two-temperature models exhibit unacceptably large uncertainties in the QoI predictions.

  5. Animal models of prenatal immune challenge and their contribution to the study of schizophrenia: a systematic review

    Directory of Open Access Journals (Sweden)

    D.S. Macêdo

    2012-03-01

    Full Text Available Prenatal immune challenge (PIC in pregnant rodents produces offspring with abnormalities in behavior, histology, and gene expression that are reminiscent of schizophrenia and autism. Based on this, the goal of this article was to review the main contributions of PIC models, especially the one using the viral-mimetic particle polyriboinosinic-polyribocytidylic acid (poly-I:C, to the understanding of the etiology, biological basis and treatment of schizophrenia. This systematic review consisted of a search of available web databases (PubMed, SciELO, LILACS, PsycINFO, and ISI Web of Knowledge for original studies published in the last 10 years (May 2001 to October 2011 concerning animal models of PIC, focusing on those using poly-I:C. The results showed that the PIC model with poly-I:C is able to mimic the prodrome and both the positive and negative/cognitive dimensions of schizophrenia, depending on the specific gestation time window of the immune challenge. The model resembles the neurobiology and etiology of schizophrenia and has good predictive value. In conclusion, this model is a robust tool for the identification of novel molecular targets during prenatal life, adolescence and adulthood that might contribute to the development of preventive and/or treatment strategies (targeting specific symptoms, i.e., positive or negative/cognitive for this devastating mental disorder, also presenting biosafety as compared to viral infection models. One limitation of this model is the incapacity to model the full spectrum of immune responses normally induced by viral exposure.

  6. Methodological quality and reporting of generalized linear mixed models in clinical medicine (2000-2012): a systematic review.

    Science.gov (United States)

    Casals, Martí; Girabent-Farrés, Montserrat; Carrasco, Josep L

    2014-01-01

    Modeling count and binary data collected in hierarchical designs have increased the use of Generalized Linear Mixed Models (GLMMs) in medicine. This article presents a systematic review of the application and quality of results and information reported from GLMMs in the field of clinical medicine. A search using the Web of Science database was performed for published original articles in medical journals from 2000 to 2012. The search strategy included the topic "generalized linear mixed models","hierarchical generalized linear models", "multilevel generalized linear model" and as a research domain we refined by science technology. Papers reporting methodological considerations without application, and those that were not involved in clinical medicine or written in English were excluded. A total of 443 articles were detected, with an increase over time in the number of articles. In total, 108 articles fit the inclusion criteria. Of these, 54.6% were declared to be longitudinal studies, whereas 58.3% and 26.9% were defined as repeated measurements and multilevel design, respectively. Twenty-two articles belonged to environmental and occupational public health, 10 articles to clinical neurology, 8 to oncology, and 7 to infectious diseases and pediatrics. The distribution of the response variable was reported in 88% of the articles, predominantly Binomial (n = 64) or Poisson (n = 22). Most of the useful information about GLMMs was not reported in most cases. Variance estimates of random effects were described in only 8 articles (9.2%). The model validation, the method of covariate selection and the method of goodness of fit were only reported in 8.0%, 36.8% and 14.9% of the articles, respectively. During recent years, the use of GLMMs in medical literature has increased to take into account the correlation of data when modeling qualitative data or counts. According to the current recommendations, the quality of reporting has room for improvement regarding the

  7. A systematic stiffness-temperature model for polymers and applications to the prediction of composite behavior

    Science.gov (United States)

    Mahieux, Celine Agnes

    Polymer matrix composites (PMC's) are now being used more and more extensively and over wider ranges of service conditions. Large changes in pressure, chemical environment or temperature influence the mechanical response of such composites. In the present effort, we focus on temperature, a parameter of primary interest in almost all engineering applications. In order to design composite structures without having to perform extensive experiments (virtual design), the necessity of establishing theoretical models that relate the macroscopic response of the structure to the microscopic properties of the constituents arises. In the first part of the present work, a new stiffness versus temperature model is established. The model is validated using data from the literature. The influence of the different polymer's properties (Molecular weight, crystallinity, and filler content) on the model are studied by performing experiments on different grades of four polymers PMMA, PEEK, PPS, and PB. This statistical model is proven to be applicable to very different polymers (elastomers, thermoplastics, crystalline, amorphous, cross-linked, linear, filled, unfilled...) over wide temperature ranges (from the glassy state to the flow region). The most attractive feature of the proposed model is the capability to enable a description of the polymer's mechanical behavior within and across the property transition regions. In order to validate the feasibility of using the model to predict the mechanical response of polymer matrix composites, the stiffness-temperature model is used in various micromechanical models (rule of mixtures, compression models for the life prediction of unidirectional PMC's in end-loaded bending...). The model is also inserted in the MRLife prediction code to predict the remaining strength and life of unidirectional PMC's in fatigue bending. End-loaded fatigue experiments were performed. A good correlation between theoretical and experimental results is observed

  8. A systematic approach to the modelling of measurements for uncertainty evaluation

    International Nuclear Information System (INIS)

    Sommer, K D; Weckenmann, A; Siebert, B R L

    2005-01-01

    The evaluation of measurement uncertainty is based on both, the knowledge about the measuring process and the quantities which influence the measurement result. The knowledge about the measuring process is represented by the model equation which expresses the interrelation between the measurand and the input quantities. Therefore, the modelling of the measurement is a key element of modern uncertainty evaluation. A modelling concept has been developed that is based on the idea of the measuring chain. It gets on with only a few generic model structures. From this concept, a practical stepwise procedure has been derived

  9. A Systematic Review of the Effect of Therapists' Internalized Models of Relationships on the Quality of the Therapeutic Relationship.

    Science.gov (United States)

    Steel, Catherine; Macdonald, James; Schroder, Thomas

    2018-01-01

    Previous reviews have found equivocal evidence of an association between therapists' internalized relational models and the therapeutic relationship and have neglected empirical literature based on Sullivan's notion of introject. This review expanded upon previous reviews to examine the effect of therapist internalized relational models on a broader conceptualization of the therapeutic relationship. Systematic search processes identified 22 papers measuring therapist attachment and/or introject and therapeutic relationship: 19 on therapist attachment, 5 on introject with 2 overlapping. Overall, despite heterogeneity in design and variable methodological quality, evidence suggests that therapist attachment affects therapeutic relationship quality, observed in client-rated evaluation, therapist negative countertransference, empathy, and problems in therapy. Interaction effects between client and therapist attachment style were also found. Evidence suggesting that therapist introject also affects therapeutic relationship quality, including therapists' manner and feelings toward their clients, was stronger. Evidence clearly shows that therapists' internalized relational models affect the therapeutic relationship. More research is necessary to clarify exactly how therapist and client internalized relational models interact and translate these findings into clinical practice. © 2017 Wiley Periodicals, Inc.

  10. A trans-Amazonian screening of mtDNA reveals deep intraspecific divergence in forest birds and suggests a vast underestimation of species diversity.

    Directory of Open Access Journals (Sweden)

    Borja Milá

    Full Text Available The Amazonian avifauna remains severely understudied relative to that of the temperate zone, and its species richness is thought to be underestimated by current taxonomy. Recent molecular systematic studies using mtDNA sequence reveal that traditionally accepted species-level taxa often conceal genetically divergent subspecific lineages found to represent new species upon close taxonomic scrutiny, suggesting that intraspecific mtDNA variation could be useful in species discovery. Surveys of mtDNA variation in Holarctic species have revealed patterns of variation that are largely congruent with species boundaries. However, little information exists on intraspecific divergence in most Amazonian species. Here we screen intraspecific mtDNA genetic variation in 41 Amazonian forest understory species belonging to 36 genera and 17 families in 6 orders, using 758 individual samples from Ecuador and French Guiana. For 13 of these species, we also analyzed trans-Andean populations from the Ecuadorian Chocó. A consistent pattern of deep intraspecific divergence among trans-Amazonian haplogroups was found for 33 of the 41 taxa, and genetic differentiation and genetic diversity among them was highly variable, suggesting a complex range of evolutionary histories. Mean sequence divergence within families was the same as that found in North American birds (13%, yet mean intraspecific divergence in Neotropical species was an order of magnitude larger (2.13% vs. 0.23%, with mean distance between intraspecific lineages reaching 3.56%. We found no clear relationship between genetic distances and differentiation in plumage color. Our results identify numerous genetically and phenotypically divergent lineages which may result in new species-level designations upon closer taxonomic scrutiny and thorough sampling, although lineages in the tropical region could be older than those in the temperate zone without necessarily representing separate species. In

  11. Sleep Deprivation and Oxidative Stress in Animal Models: A Systematic Review

    Directory of Open Access Journals (Sweden)

    Gabriel Villafuerte

    2015-01-01

    Full Text Available Because the function and mechanisms of sleep are partially clear, here we applied a meta-analysis to address the issue whether sleep function includes antioxidative properties in mice and rats. Given the expansion of the knowledge in the sleep field, it is indeed ambitious to describe all mammals, or other animals, in which sleep shows an antioxidant function. However, in this paper we reviewed the current understanding from basic studies in two species to drive the hypothesis that sleep is a dynamic-resting state with antioxidative properties. We performed a systematic review of articles cited in Medline, Scopus, and Web of Science until March 2015 using the following search terms: Sleep or sleep deprivation and oxidative stress, lipid peroxidation, glutathione, nitric oxide, catalase or superoxide dismutase. We found a total of 266 studies. After inclusion and exclusion criteria, 44 articles were included, which are presented and discussed in this study. The complex relationship between sleep duration and oxidative stress is discussed. Further studies should consider molecular and genetic approaches to determine whether disrupted sleep promotes oxidative stress.

  12. Overview of data-synthesis in systematic reviews of studies on outcome prediction models

    NARCIS (Netherlands)

    T. van den Berg (Tobias); M.W. Heymans (Martijn); O. Leone; D. Vergouw (David); J. Hayden (Jill); A.P. Verhagen (Arianne); H.C. de Vet (Henrica C)

    2013-01-01

    textabstractBackground: Many prognostic models have been developed. Different types of models, i.e. prognostic factor and outcome prediction studies, serve different purposes, which should be reflected in how the results are summarized in reviews. Therefore we set out to investigate how authors of

  13. Teaching Personal and Social Responsibility Model-Based Programmes in Physical Education: A Systematic Review

    Science.gov (United States)

    Pozo, Pablo; Grao-Cruces, Alberto; Pérez-Ordás, Raquel

    2018-01-01

    The purpose of this study was to conduct a review of research on the Teaching Personal and Social Responsibility model-based programme within physical education. Papers selected for analysis were found through searches of Web of Science, SportDiscus (EBSCO), SCOPUS, and ERIC (ProQuest) databases. The keywords "responsibility model" and…

  14. Developing and Optimising the Use of Logic Models in Systematic Reviews: Exploring Practice and Good Practice in the Use of Programme Theory in Reviews

    Science.gov (United States)

    Kneale, Dylan; Thomas, James; Harris, Katherine

    2015-01-01

    Background Logic models are becoming an increasingly common feature of systematic reviews, as is the use of programme theory more generally in systematic reviewing. Logic models offer a framework to help reviewers to ‘think’ conceptually at various points during the review, and can be a useful tool in defining study inclusion and exclusion criteria, guiding the search strategy, identifying relevant outcomes, identifying mediating and moderating factors, and communicating review findings. Methods and Findings In this paper we critique the use of logic models in systematic reviews and protocols drawn from two databases representing reviews of health interventions and international development interventions. Programme theory featured only in a minority of the reviews and protocols included. Despite drawing from different disciplinary traditions, reviews and protocols from both sources shared several limitations in their use of logic models and theories of change, and these were used almost unanimously to solely depict pictorially the way in which the intervention worked. Logic models and theories of change were consequently rarely used to communicate the findings of the review. Conclusions Logic models have the potential to be an aid integral throughout the systematic reviewing process. The absence of good practice around their use and development may be one reason for the apparent limited utility of logic models in many existing systematic reviews. These concerns are addressed in the second half of this paper, where we offer a set of principles in the use of logic models and an example of how we constructed a logic model for a review of school-based asthma interventions. PMID:26575182

  15. Biofeedback as complementary treatment in patients with epilepsy – an underestimated therapeutic option? Review, results, discussion

    Directory of Open Access Journals (Sweden)

    Uhlmann Carmen

    2016-12-01

    Full Text Available Background. Biofeedback methods represent side effect free complementary options in the treatment of epilepsy. In this paper we review the current status of these methods in terms of clinical study results and their evaluation by systematic review papers. Possible mechanisms of action in biofeedback methods are discussed.

  16. Systematic review of the synergist muscle ablation model for compensatory hypertrophy.

    Science.gov (United States)

    Terena, Stella Maris Lins; Fernandes, Kristianne Porta Santos; Bussadori, Sandra Kalill; Deana, Alessandro Melo; Mesquita-Ferrari, Raquel Agnelli

    2017-02-01

    The aim was to evaluate the effectiveness of the experimental synergists muscle ablation model to promote muscle hypertrophy, determine the period of greatest hypertrophy and its influence on muscle fiber types and determine differences in bilateral and unilateral removal to reduce the number of animals used in this model. Following the application of the eligibility criteria for the mechanical overload of the plantar muscle in rats, nineteen papers were included in the review. The results reveal a greatest hypertrophy occurring between days 12 and 15, and based on the findings, synergist muscle ablation is an efficient model for achieving rapid hypertrophy and the contralateral limb can be used as there was no difference between unilateral and bilateral surgery, which reduces the number of animals used in this model. This model differs from other overload models (exercise and training) regarding the characteristics involved in the hypertrophy process (acute) and result in a chronic muscle adaptation with selective regulation and modification of fast-twitch fibers in skeletal muscle. This is an efficient and rapid model for compensatory hypertrophy.

  17. Systematic review of the synergist muscle ablation model for compensatory hypertrophy

    Directory of Open Access Journals (Sweden)

    Stella Maris Lins Terena

    Full Text Available Summary Objective: The aim was to evaluate the effectiveness of the experimental synergists muscle ablation model to promote muscle hypertrophy, determine the period of greatest hypertrophy and its influence on muscle fiber types and determine differences in bilateral and unilateral removal to reduce the number of animals used in this model. Method: Following the application of the eligibility criteria for the mechanical overload of the plantar muscle in rats, nineteen papers were included in the review. Results: The results reveal a greatest hypertrophy occurring between days 12 and 15, and based on the findings, synergist muscle ablation is an efficient model for achieving rapid hypertrophy and the contralateral limb can be used as there was no difference between unilateral and bilateral surgery, which reduces the number of animals used in this model. Conclusion: This model differs from other overload models (exercise and training regarding the characteristics involved in the hypertrophy process (acute and result in a chronic muscle adaptation with selective regulation and modification of fast-twitch fibers in skeletal muscle. This is an efficient and rapid model for compensatory hypertrophy.

  18. Model-Based Economic Evaluation of Treatments for Depression: A Systematic Literature Review

    DEFF Research Database (Denmark)

    Kolovos, Spyros; Bosmans, Judith E.; Riper, Heleen

    2017-01-01

    eligible if they used a health economic model with quality-adjusted life-years or disability-adjusted life-years as an outcome measure. Data related to various methodological characteristics were extracted from the included studies. The available modelling techniques were evaluated based on 11 predefined......, and DES models in seven.ConclusionThere were substantial methodological differences between the studies. Since the individual history of each patient is important for the prognosis of depression, DES and ISM simulation methods may be more appropriate than the others for a pragmatic representation...

  19. International BMI-for-age references underestimate thinness and overestimate overweight and obesity in Bolivian adolescents.

    Science.gov (United States)

    Baya Botti, A; Pérez-Cueto, F J A; Vasquez Monllor, P A; Kolsteren, P W

    2010-01-01

    Since no growth standards for adolescents exist and a single reference applicable everywhere is still in debate, it is recognized that the best reference should be derived from the growth pattern of the healthy population that will use it. In 2007 a study developed references for body mass index for 12th to 18th y Bolivian school adolescent (BAP. To compare nutritional status outcomes applying BMI references from the BAP, the Center for Disease Control and Prevention CDC 2000, the International Task Force (IOTF), and the 2007 WHO, to determine appropriateness of use in Bolivian adolescents. References were applied in 3306 adolescents, 45.0% male, 55% female, 12th to 18th y selected from a nationally representative sample. Main findings reveal that the CDC and the 2007 WHO underestimate underweight (preferences overestimate overweight (preferences for the use of BAP in Bolivia which reflects its healthy adolescent population growth pattern. International references may lead to incorrect conclusions when applied on Bolivian adolescents. They could deflect efforts from population which need prompt intervention and mislead treatments and budget to unnecessary ones. We recommend validation of international references where appropriate until a standard is released.

  20. Panoramic radiographs underestimate extensions of the anterior loop and mandibular incisive canal

    Energy Technology Data Exchange (ETDEWEB)

    De Brito, Ana Caroline Ramos; Nejaim, Yuri; De Freitas, Deborah Queiroz [Dept. of Oral Diagnosis, Division of Oral Radiology, Piracicaba Dental School, University of Campinas, Sao Paulo (Brazil); De Oliveira Santos, Christiano [Dept. of Stomatology, Public Oral Health and Forensic Dentistry, School of Dentistry of Ribeirao Preto, University of Sao Paulo, Sao Paulo (Brazil)

    2016-09-15

    The purpose of this study was to detect the anterior loop of the mental nerve and the mandibular incisive canal in panoramic radiographs (PAN) and cone-beam computed tomography (CBCT) images, as well as to determine the anterior/mesial extension of these structures in panoramic and cross-sectional reconstructions using PAN and CBCT images. Images (both PAN and CBCT) from 90 patients were evaluated by 2 independent observers. Detection of the anterior loop and the incisive canal were compared between PAN and CBCT. The anterior/mesial extension of these structures was compared between PAN and both cross-sectional and panoramic CBCT reconstructions. In CBCT, the anterior loop and the incisive canal were observed in 7.7% and 24.4% of the hemimandibles, respectively. In PAN, the anterior loop and the incisive canal were detected in 15% and 5.5% of cases, respectively. PAN presented more difficulties in the visualization of structures. The anterior/mesial extensions ranged from 0.0 mm to 19.0 mm on CBCT. PAN underestimated the measurements by approximately 2.0 mm. CBCT appears to be a more reliable imaging modality than PAN for preoperative workups of the anterior mandible. Individual variations in the anterior/mesial extensions of the anterior loop of the mental nerve and the mandibular incisive canal mean that is not prudent to rely on a general safe zone for implant placement or bone surgery in the interforaminal region.

  1. Physician's manual reporting underestimates mortality: evidence from a population-based HIV/AIDS treatment program

    Directory of Open Access Journals (Sweden)

    Yip Benita

    2010-10-01

    Full Text Available Abstract Background In clinical and cohort research, mortality estimates are often derived from manual reports generated by physicians or electronic reports from vital event registries. We examined the rate of underreporting of deaths by manual methods as compared with electronic reports from a vital event registry. Methods The retrospective analyses included deaths among participants registered in an observational cohort who initiated highly-active antiretroviral therapy (HAART between August 1, 1996 and June 30, 2006. Deaths were routinely reported manually by physicians and through annual electronic record linkages with a population-based vital event registry. Multivariate logistic regression was carried out to assess independent predictors of death reporting by manual methods. Results Of the 3,116 individuals included in the analyses, 622 (20.0% died during follow-up. Manual reporting by physicians only identified 377 (60.6%, while electronic linkages captured 598 (96.1% of all deaths. Multivariate analysis indicated that deaths among individuals with lower CD4 cell count, higher HIV plasma viral load, a history of injection drug use, and under the care of an HIV-experienced physicians were more likely to be reported manually. Furthermore, non-accidental deaths were more likely to be reported manually, and manual reporting of deaths increased over time. Conclusions Relying only on manual reports to ascertain deaths significantly underestimates the total number of deaths in the population. This can generate important biases when evaluating the impact of therapeutic interventions in the populational setting.

  2. Age, risk assessment, and sanctioning: Overestimating the old, underestimating the young.

    Science.gov (United States)

    Monahan, John; Skeem, Jennifer; Lowenkamp, Christopher

    2017-04-01

    While many extoll the potential contribution of risk assessment to reducing the human and fiscal costs of mass incarceration without increasing crime, others adamantly oppose the incorporation of risk assessment in sanctioning. The principal concern is that any benefits in terms of reduced rates of incarceration achieved through the use of risk assessment will be offset by costs to social justice-which are claimed to be inherent in any risk assessment process that relies on variables for which offenders bear no responsibility, such as race, gender, and age. Previous research has addressed the variables of race and gender. Here, based on a sample of 7,350 federal offenders, we empirically test the predictive fairness of an instrument-the Post Conviction Risk Assessment (PCRA)-that includes the variable of age. We found that the strength of association between PCRA scores and future arrests was similar across younger (i.e., 25 years and younger), middle (i.e., 26-40 years), and older (i.e., 41 years and older) age groups (AUC values .70 or higher). Nevertheless, rates of arrest within each PCRA risk category were consistently lower for older than for younger offenders. Despite its inclusion of age as a risk factor, PCRA scores overestimated rates of recidivism for older offenders and underestimated rates of recidivism for younger offenders. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  3. Consequences of neurologic lesions assessed by Barthel Index after Botox® injection may be underestimated

    Directory of Open Access Journals (Sweden)

    Dionyssiotis Y

    2012-10-01

    Full Text Available Y Dionyssiotis,1,2 D Kiourtidis,3 A Karvouni,3 A Kaliontzoglou,3 I Kliafas31Medical Department, Rehabilitation Center Amyntaio, General Hospital of Florina, Amyntaio, Florina, 2Physical Medicine and Rehabilitation Department, Rhodes General Hospital, Rhodes, Dodecanese, 3Neurologic Department, Rhodes General Hospital, Rhodes, Dodecanese, GreecePurpose: The aim of this study was to investigate whether the consequences of neurologic lesions are underestimated when the Barthel Index (BI is used to assess the clinical outcome of botulinum toxin injection.Patients and methods: The records for all in- and outpatients with various neurologic lesions (stroke, multiple sclerosis, spinal cord injury, traumatic brain injury, and so forth who had been referred to the authors’ departments and who had received botulinum toxin type A (Botox® for spasticity within a 4-year period (2008–2011 were examined retrospectively. BI data were collected and analyzed.Results: The BI score was found to have increased in follow-up assessments (P = 0.048. No correlation was found between the degree of spasticity and the BI score.Conclusion: The specific injection of Botox in patients with neurologic lesions was not strongly correlated with a significant functional outcome according to the BI. The results of this study suggest that clinicians need to look at other measurement scales for the assessment of significant outcomes of Botox in the rehabilitation process after neurologic lesions.Keywords: botulinum toxin type A, spasticity, stroke, multiple sclerosis

  4. Underestimated effects of sediments on enhanced startup performance of biofilm systems for polluted source water pretreatment.

    Science.gov (United States)

    Lv, Zheng-Hui; Wang, Jing; Yang, Guang-Feng; Feng, Li-Juan; Mu, Jun; Zhu, Liang; Xu, Xiang-Yang

    2018-02-01

    In order to evaluate the enhancement mechanisms of enhanced startup performance in biofilm systems for polluted source water pretreatment, three lab-scale reactors with elastic stereo media (ESM) were operated under different enhanced sediment and hydraulic agitation conditions. It is interesting to found the previously underestimated or overlooked effects of sediment on the enhancement of pollutants removal performance and enrichment of functional bacteria in biofilm systems. The maximum NH 4 + -N removal rate of 0.35 mg L -1 h -1 in sediment enhanced condition was 2.19 times of that in control reactor. Sediment contributed to 42.0-56.5% of NH 4 + -N removal and 15.4-41.2% of total nitrogen removal in different reactors under different operation conditions. The enhanced hydraulic agitation with sediment further improved the operation performance and accumulation of functional bacteria. Generally, Proteobacteria (48.9-52.1%), Bacteroidetes (18.9-20.8%) and Actinobacteria (15.7-18.5%) were dominant in both sediment and ESM bioiflm at  phylum level. The potentially functional bacteria found in sediment and ESM biofilm samples with some functional bacteria mainly presented in sediment samples only (e.g., Genera Bacillus and Lactococcus of Firmicutes phylum) may commonly contribute to the removal of nitrogen and organics.

  5. Underestimated Halogen Bonds Forming with Protein Backbone in Protein Data Bank.

    Science.gov (United States)

    Zhang, Qian; Xu, Zhijian; Shi, Jiye; Zhu, Weiliang

    2017-07-24

    Halogen bonds (XBs) are attracting increasing attention in biological systems. Protein Data Bank (PDB) archives experimentally determined XBs in biological macromolecules. However, no software for structure refinement in X-ray crystallography takes into account XBs, which might result in the weakening or even vanishing of experimentally determined XBs in PDB. In our previous study, we showed that side-chain XBs forming with protein side chains are underestimated in PDB on the basis of the phenomenon that the proportion of side-chain XBs to overall XBs decreases as structural resolution becomes lower and lower. However, whether the dominant backbone XBs forming with protein backbone are overlooked is still a mystery. Here, with the help of the ratio (R F ) of the observed XBs' frequency of occurrence to their frequency expected at random, we demonstrated that backbone XBs are largely overlooked in PDB, too. Furthermore, three cases were discovered possessing backbone XBs in high resolution structures while losing the XBs in low resolution structures. In the last two cases, even at 1.80 Å resolution, the backbone XBs were lost, manifesting the urgent need to consider XBs in the refinement process during X-ray crystallography study.

  6. Field Measurements Indicate Unexpected, Serious Underestimation of Mussel Heart Rates and Thermal Tolerance by Laboratory Studies.

    Directory of Open Access Journals (Sweden)

    Morgana Tagliarolo

    Full Text Available Attempts to predict the response of species to long-term environmental change are generally based on extrapolations from laboratory experiments that inevitably simplify the complex interacting effects that occur in the field. We recorded heart rates of two genetic lineages of the brown mussel Perna perna over a full tidal cycle in-situ at two different sites in order to evaluate the cardiac responses of the two genetic lineages present on the South African coast to temperature and the immersion/emersion cycle. "Robomussel" temperature loggers were used to monitor thermal conditions at the two sites over one year. Comparison with live animals showed that robomussels provided a good estimate of mussel body temperatures. A significant difference in estimated body temperatures was observed between the sites and the results showed that, under natural conditions, temperatures regularly approach or exceed the thermal limits of P. perna identified in the laboratory. The two P. perna lineages showed similar tidal and diel patterns of heart rate, with higher cardiac activity during daytime immersion and minimal values during daytime emersion. Comparison of the heart rates measured in the field with data previously measured in the laboratory indicates that laboratory results seriously underestimate heart rate activity, by as much as 75%, especially during immersion. Unexpectedly, field estimates of body temperatures indicated an ability to tolerate temperatures considered lethal on the basis of laboratory measurements. This suggests that the interaction of abiotic conditions in the field does not necessarily raise vulnerability to high temperatures.

  7. 5-FU-induced cardiac toxicity - an underestimated problem in radiooncology?

    Directory of Open Access Journals (Sweden)

    Steger Felix

    2012-12-01

    Full Text Available Abstract Background 5-Fluorouracil (5-FU is an antimetabolite, which is frequently used as chemotherapeutic agent for combined chemoradiotherapy. The purpose of this study was to present the clinical course of three patients who developed severe cardiac toxicity by 5-FU and to give a review of the literature on the cardiotoxic potential of 5-FU. Results Cardiotoxicity is a rare, but relevant side effect of fluoropyrimidines. It comprehends a wide spectrum of side effects, from electrocardiogram changes (69% of cardiac events to myocardial infarction (22% and cardiogenic shock (1%. In this case series three patients with cardiotoxic events during chemoradiotherapy including 5-FU, the reaction's characteristics and their influence on further therapy are described. Two of the patients could not be treated with 5-FU any more because they had developed a myocardial ischemia, which was most likely caused by fluorouracil. Another patient, who complained about typical angina pectoris during 5-FU-infusion and had a new left anterior hemiblock, was reexposed with prophylactic administration of nitrendipine. Conclusion Cardiotoxicity caused by 5-FU is an underestimated problem in radiooncology. Especially patients without history of cardiac disease are often treated as out-patients and therefore without cardiac monitoring. Consequently asymptomatic and symptomatic cardiac events may be overlooked. The benefit of prophylactic agents remains unclear, so close cardiac monitoring is the most established method to prevent manifest cardiotoxic events.

  8. 5-FU-induced cardiac toxicity - an underestimated problem in radiooncology?

    International Nuclear Information System (INIS)

    Steger, Felix; Hautmann, Matthias G; Kölbl, Oliver

    2012-01-01

    5-Fluorouracil (5-FU) is an antimetabolite, which is frequently used as chemotherapeutic agent for combined chemoradiotherapy. The purpose of this study was to present the clinical course of three patients who developed severe cardiac toxicity by 5-FU and to give a review of the literature on the cardiotoxic potential of 5-FU. Cardiotoxicity is a rare, but relevant side effect of fluoropyrimidines. It comprehends a wide spectrum of side effects, from electrocardiogram changes (69% of cardiac events) to myocardial infarction (22%) and cardiogenic shock (1%). In this case series three patients with cardiotoxic events during chemoradiotherapy including 5-FU, the reaction's characteristics and their influence on further therapy are described. Two of the patients could not be treated with 5-FU any more because they had developed a myocardial ischemia, which was most likely caused by fluorouracil. Another patient, who complained about typical angina pectoris during 5-FU-infusion and had a new left anterior hemiblock, was reexposed with prophylactic administration of nitrendipine. Cardiotoxicity caused by 5-FU is an underestimated problem in radiooncology. Especially patients without history of cardiac disease are often treated as out-patients and therefore without cardiac monitoring. Consequently asymptomatic and symptomatic cardiac events may be overlooked. The benefit of prophylactic agents remains unclear, so close cardiac monitoring is the most established method to prevent manifest cardiotoxic events

  9. Have we underestimated the kinematic and kinetic benefits of non-ballistic motion?

    Science.gov (United States)

    Frost, David M; Cronin, John B; Newton, Robert U

    2008-09-01

    Explosive upper-body movements, with which the load is not thrown (non-ballistic), may comprise a phase during which forces are produced in opposition to the motion of the load. Thirty men completed three test sessions (free weight, ballistic, and pneumatic), each consisting of a one-repetition maximum (1-RM) and four explosive repetitions of a bench press at six loads (15, 30, 45, 60, 75, and 90% 1-RM). The end of the lifting phase for the non-ballistic conditions (free weight and pneumatic) was defined by: the point of peak barbell displacement and the point at which the vertical force became negative (positive work). When analysed by peak displacement, the ballistic condition elicited significantly greater mean velocity, force, and power at loads of 15-60% 1-RM compared with the free weight condition. When the period of negative work was removed, the mean free weight velocity, force, and power at loads below 60% 1-RM increased. Consequently, the only differences between the free weight and ballistic conditions were found at loads of 15% and 30% 1-RM. Including a period of negative work may underestimate all kinematic and kinetic variables dependent on the time to, or position of, the end of the lifting phase, for non-ballistic efforts.

  10. Modeling of systematic retention of beryllium in rats. Extrapolation to humans

    International Nuclear Information System (INIS)

    Montero Prieto, M.; Vidania Munoz, R. de.

    1994-01-01

    In this work, we analyzed different approaches, assayed in order to numerically describe the systemic behaviour of Beryllium. The experimental results used in this work, were previously obtained by Furchner et al. (1973), using Sprague-Dawley rats, and other animal species. Furchner's work includes the obtained model for whole body retention in rats but not for each target organ. In this work we present the results obtained by modeling the kinetic behaviour of Beryllium in several target organs. The results of this kind of models were used in order to establish correlations among the estimated kinetic constants. The parameters of the model were extrapolated to humans and, finally, compared with other previously published

  11. Systematic Identification of Stakeholders for Engagement with Systems Modeling Efforts in the Snohomish Basin, Washington, USA

    Science.gov (United States)

    Even as stakeholder engagement in systems dynamic modeling efforts is increasingly promoted, the mechanisms for identifying which stakeholders should be included are rarely documented. Accordingly, for an Environmental Protection Agency’s Triple Value Simulation (3VS) mode...

  12. Intra-arch dimensional measurement validity of laser-scanned digital dental models compared with the original plaster models: a systematic review.

    Science.gov (United States)

    De Luca Canto, G; Pachêco-Pereira, C; Lagravere, M O; Flores-Mir, C; Major, P W

    2015-05-01

    A systematic review was undertaken to evaluate the validity of intra-arch dimensional measurements made from laser-scanned digital dental models in comparison with measurements directly obtained from the original plaster casts (gold standard). Finally included articles were only those reporting studies that compared measurements from digital models produced from laser scanning against their plaster models. Measurements from the original plaster models should have been made using a manual or digital caliper (gold standard). Articles that used scans from impressions or digital photographs were discarded. Detailed individual search strategies for Cochrane, EMBASE, MEDLINE, PubMed, and LILACS were developed. The references cited in the selected articles were also checked for any references that could have been missed in the electronic database searches. A partial gray literature search was undertaken using Google Scholar. The methodology of selected studies was evaluated using the 14-item quality assessment tool for diagnostic accuracy studies (QUADAS). Only 16 studies were finally included for the qualitative/quantitative synthesis. The selected studies consistently agree that the validity of measurements obtained after using a laser scanner from plaster models is similar to direct measurements. Any stated differences would be unlikely clinically relevant. There is consistent scientific evidence to support the validity of measurements from digital dental models in comparison with intra-arch dimensional measurements directly obtained from them. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  13. A systematic model identification method for chemical transformation pathways - the case of heroin biomarkers in wastewater.

    Science.gov (United States)

    Ramin, Pedram; Valverde-Pérez, Borja; Polesel, Fabio; Locatelli, Luca; Plósz, Benedek Gy

    2017-08-24

    This study presents a novel statistical approach for identifying sequenced chemical transformation pathways in combination with reaction kinetics models. The proposed method relies on sound uncertainty propagation by considering parameter ranges and associated probability distribution obtained at any given transformation pathway levels as priors for parameter estimation at any subsequent transformation levels. The method was applied to calibrate a model predicting the transformation in untreated wastewater of six biomarkers, excreted following human metabolism of heroin and codeine. The method developed was compared to parameter estimation methods commonly encountered in literature (i.e., estimation of all parameters at the same time and parameter estimation with fix values for upstream parameters) by assessing the model prediction accuracy, parameter identifiability and uncertainty analysis. Results obtained suggest that the method developed has the potential to outperform conventional approaches in terms of prediction accuracy, transformation pathway identification and parameter identifiability. This method can be used in conjunction with optimal experimental designs to effectively identify model structures and parameters. This method can also offer a platform to promote a closer interaction between analytical chemists and modellers to identify models for biochemical transformation pathways, being a prominent example for the emerging field of wastewater-based epidemiology.

  14. Development of systematic models for aerosol agglomeration and spray removal under severe accident conditions

    International Nuclear Information System (INIS)

    Kajimoto, Mitsuhiro

    2008-01-01

    Radionuclide behavior during various severe accident conditions has been addressed as one of the important issues to discuss environmental safety in nuclear power plants. The present paper deals with the development of analytical models and their validations for the agglomeration of multiple-component aerosol and spray removal that controls source terms to the environment of both aerosols and gaseous radionuclides during recirculation mode operation in a containment system for a light water reactor. As for aerosol agglomeration, the single collision kernel model that can cover all types of two-body collision of aerosol was developed. In addition, the dynamic model that can treat aerosol and vapor transfer leading to the equilibrium condition under the containment spray operation was developed. The validations of the present models for multiple-component aerosol growth by agglomeration were performed by comparisons with Nuclear Safety Pilot Plant (NSPP) experiments at Oak Ridge National Laboratory (ORNL) and AB experiments at Hanford Engineering National Laboratory (HEDL). In addition, the spray removal models were applied to the analysis of containment spray experiment (CSE) at HEDL. The results calculated by the models showed good agreements with experimental results. (author)

  15. Pathway-Consensus Approach to Metabolic Network Reconstruction for Pseudomonas putida KT2440 by Systematic Comparison of Published Models.

    Science.gov (United States)

    Yuan, Qianqian; Huang, Teng; Li, Peishun; Hao, Tong; Li, Feiran; Ma, Hongwu; Wang, Zhiwen; Zhao, Xueming; Chen, Tao; Goryanin, Igor

    2017-01-01

    Over 100 genome-scale metabolic networks (GSMNs) have been published in recent years and widely used for phenotype prediction and pathway design. However, GSMNs for a specific organism reconstructed by different research groups usually produce inconsistent simulation results, which makes it difficult to use the GSMNs for precise optimal pathway design. Therefore, it is necessary to compare and identify the discrepancies among networks and build a consensus metabolic network for an organism. Here we proposed a process for systematic comparison of metabolic networks at pathway level. We compared four published GSMNs of Pseudomonas putida KT2440 and identified the discrepancies leading to inconsistent pathway calculation results. The mistakes in the models were corrected based on information from literature so that all the calculated synthesis and uptake pathways were the same. Subsequently we built a pathway-consensus model and then further updated it with the latest genome annotation information to obtain modelPpuQY1140 for P. putida KT2440, which includes 1140 genes, 1171 reactions and 1104 metabolites. We found that even small errors in a GSMN could have great impacts on the calculated optimal pathways and thus may lead to incorrect pathway design strategies. Careful investigation of the calculated pathways during the metabolic network reconstruction process is essential for building proper GSMNs for pathway design.

  16. Supplementation with Curcuma longa reverses neurotoxic and behavioral damage in models of Alzheimer's disease: A systematic review.

    Science.gov (United States)

    da Costa, Ianara Mendonca; de Moura Freire, Marco Aurelio; de Paiva Cavalcanti, Jose Rodolfo Lopes; Pessoa de Araujo, Dayane; Norrara, Bianca; Rosa, Isleania Maria Marques Moreira; Pereira de Azevedo, Eduardo; Meneses do Rego, Amalia Cinthia; Filho, Irami Araujo; Guzen, Fausto Pierdona

    2018-01-16

    The formation of senile plaques and neurofibrillary tangles of the tau protein are the main pathological mechanism of Alzheimer's disease (AD). Current therapies for AD offer discrete benefits to the clinical symptoms and do not prevent the continuing degeneration of neuronal cells. Therefore, novel therapeutic strategies have long been investigated, where curcumin (Curcuma longa) has shown some properties that can prevent the deleterious processes involved in neurodegenerative diseases. The aim of the present work is to review studies that addressed the effects of curcumin in experimental models (in vivo and in vitro) for AD. This study is a systematic review conducted between January and June 2017, in which a consultation of scientific articles from indexed periodicals was carried out in Science Direct, United States National Library of Medicine (PubMed), Cochrane Library and Scielo databases, using the following descriptors: "Curcuma longa", "Curcumin" and "Alzheimer's disease". A total of 32 studies were analyzed, which indicated that curcumin supplementation reverses neurotoxic and behavioral damages in both in vivo and in vitro models of AD. The administration of curcumin in experimental models seems to be a promising approach in AD, even though it is suggested that additional studies must be conducted using distinct doses and through other routes of administration. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  17. The Efficacy of Trastuzumab in Animal Models of Breast Cancer: A Systematic Review and Meta-Analysis.

    Directory of Open Access Journals (Sweden)

    Jiarong Chen

    Full Text Available Breast cancer is the most frequent cancers and is the second leading cause of cancer death among women. Trastuzumab is an effective treatment, the first monoclonal antibody directed against the human epidermal growth factor receptor 2 (HER2. To inform the development of other effective treatments we report summary estimates of efficacy of trastuzumab on survival and tumour volume in animal models of breast cancer.We searched PubMed and EMBASE systematically to identify publications testing trastuzumab in animal models of breast cancer. Data describing tumour volume, median survival and animal features were extracted and we assessed quality using a 12-item checklist. We analysed the impact of study design and quality and evidence for publication bias.We included data from 83 studies reporting 169 experiments using 2076 mice. Trastuzumab treatment caused a substantial reduction in tumour growth, with tumours in treated animals growing to 32.6% of the volume of tumours in control animals (95%CI 27.8%-38.2%. Median survival was prolonged by a factor of 1.45 (1.30-1.62. Many study design and quality features accounted for between-study heterogeneity and we found evidence suggesting publication bias.We have found trastuzumab to be effective in animal breast cancer models across a range of experimental circumstances. However the presence of publication bias and a low prevalence of measures to reduce bias provide a focus for future improvements in preclinical breast cancer research.

  18. Pathway-Consensus Approach to Metabolic Network Reconstruction for Pseudomonas putida KT2440 by Systematic Comparison of Published Models.

    Directory of Open Access Journals (Sweden)

    Qianqian Yuan

    Full Text Available Over 100 genome-scale metabolic networks (GSMNs have been published in recent years and widely used for phenotype prediction and pathway design. However, GSMNs for a specific organism reconstructed by different research groups usually produce inconsistent simulation results, which makes it difficult to use the GSMNs for precise optimal pathway design. Therefore, it is necessary to compare and identify the discrepancies among networks and build a consensus metabolic network for an organism. Here we proposed a process for systematic comparison of metabolic networks at pathway level. We compared four published GSMNs of Pseudomonas putida KT2440 and identified the discrepancies leading to inconsistent pathway calculation results. The mistakes in the models were corrected based on information from literature so that all the calculated synthesis and uptake pathways were the same. Subsequently we built a pathway-consensus model and then further updated it with the latest genome annotation information to obtain modelPpuQY1140 for P. putida KT2440, which includes 1140 genes, 1171 reactions and 1104 metabolites. We found that even small errors in a GSMN could have great impacts on the calculated optimal pathways and thus may lead to incorrect pathway design strategies. Careful investigation of the calculated pathways during the metabolic network reconstruction process is essential for building proper GSMNs for pathway design.

  19. Modeling companion diagnostics in economic evaluations of targeted oncology therapies: systematic review and methodological checklist.

    Science.gov (United States)

    Doble, Brett; Tan, Marcus; Harris, Anthony; Lorgelly, Paula

    2015-02-01

    The successful use of a targeted therapy is intrinsically linked to the ability of a companion diagnostic to correctly identify patients most likely to benefit from treatment. The aim of this study was to review the characteristics of companion diagnostics that are of importance for inclusion in an economic evaluation. Approaches for including these characteristics in model-based economic evaluations are compared with the intent to describe best practice methods. Five databases and government agency websites were searched to identify model-based economic evaluations comparing a companion diagnostic and subsequent treatment strategy to another alternative treatment strategy with model parameters for the sensitivity and specificity of the companion diagnostic (primary synthesis). Economic evaluations that limited model parameters for the companion diagnostic to only its cost were also identified (secondary synthesis). Quality was assessed using the Quality of Health Economic Studies instrument. 30 studies were included in the review (primary synthesis n = 12; secondary synthesis n = 18). Incremental cost-effectiveness ratios may be lower when the only parameter for the companion diagnostic included in a model is the cost of testing. Incorporating the test's accuracy in addition to its cost may be a more appropriate methodological approach. Altering the prevalence of the genetic biomarker, specific population tested, type of test, test accuracy and timing/sequence of multiple tests can all impact overall model results. The impact of altering a test's threshold for positivity is unknown as it was not addressed in any of the included studies. Additional quality criteria as outlined in our methodological checklist should be considered due to the shortcomings of standard quality assessment tools in differentiating studies that incorporate important test-related characteristics and those that do not. There is a need to refine methods for incorporating the characteristics

  20. A systematic review of the main factors that determine agility in sport using structural equation modeling

    Directory of Open Access Journals (Sweden)

    Hojka Vladimir

    2016-09-01

    Full Text Available While tests of basic motor abilities such as speed, maximum strength or endurance are well recognized, testing of complex motor functions such as agility remains unresolved in current literature. Therefore, the aim of this review was to evaluate which main factor or factor structures quantitatively determine agility. In methodological detail, this review focused on research that explained or described the relationships between latent variables in a factorial model of agility using approaches such as principal component analysis, factor analysis and structural equation modeling. Four research studies met the defined inclusion criteria. No quantitative empirical research was found that tried to verify the quality of the whole suggested model of the main factors determining agility through the use of a structural equation modeling (SEM approach or a confirmatory factor analysis. From the whole structure of agility, only change of direction speed (CODS and some of its subtests were appropriately analyzed. The combination of common CODS tests is reliable and useful to estimate performance in sub-elite athletes; however, for elite athletes, CODS tests must be specific to the needs of a particular sport discipline. Sprinting and jumping tests are stronger factors for CODS than explosive strength and maximum strength tests. The authors suggest the need to verify the agility factorial model by a second generation data analysis technique such as SEM.

  1. Diagnostic accuracy and measurement sensitivity of digital models for orthodontic purposes: A systematic review.

    Science.gov (United States)

    Rossini, Gabriele; Parrini, Simone; Castroflorio, Tommaso; Deregibus, Andrea; Debernardi, Cesare L

    2016-02-01

    Our objective was to assess the accuracy, validity, and reliability of measurements obtained from virtual dental study models compared with those obtained from plaster models. PubMed, PubMed Central, National Library of Medicine Medline, Embase, Cochrane Central Register of Controlled Clinical trials, Web of Knowledge, Scopus, Google Scholar, and LILACs were searched from January 2000 to November 2014. A grading system described by the Swedish Council on Technology Assessment in Health Care and the Cochrane tool for risk of bias assessment were used to rate the methodologic quality of the articles. Thirty-five relevant articles were selected. The methodologic quality was high. No significant differences were observed for most of the studies in all the measured parameters, with the exception of the American Board of Orthodontics Objective Grading System. Digital models are as reliable as traditional plaster models, with high accuracy, reliability, and reproducibility. Landmark identification, rather than the measuring device or the software, appears to be the greatest limitation. Furthermore, with their advantages in terms of cost, time, and space required, digital models could be considered the new gold standard in current practice. Copyright © 2016 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

  2. A systematic review of the main factors that determine agility in sport using structural equation modeling.

    Science.gov (United States)

    Hojka, Vladimir; Stastny, Petr; Rehak, Tomas; Gołas, Artur; Mostowik, Aleksandra; Zawart, Marek; Musálek, Martin

    2016-09-01

    While tests of basic motor abilities such as speed, maximum strength or endurance are well recognized, testing of complex motor functions such as agility remains unresolved in current literature. Therefore, the aim of this review was to evaluate which main factor or factor structures quantitatively determine agility. In methodological detail, this review focused on research that explained or described the relationships between latent variables in a factorial model of agility using approaches such as principal component analysis, factor analysis and structural equation modeling. Four research studies met the defined inclusion criteria. No quantitative empirical research was found that tried to verify the quality of the whole suggested model of the main factors determining agility through the use of a structural equation modeling (SEM) approach or a confirmatory factor analysis. From the whole structure of agility, only change of direction speed (CODS) and some of its subtests were appropriately analyzed. The combination of common CODS tests is reliable and useful to estimate performance in sub-elite athletes; however, for elite athletes, CODS tests must be specific to the needs of a particular sport discipline. Sprinting and jumping tests are stronger factors for CODS than explosive strength and maximum strength tests. The authors suggest the need to verify the agility factorial model by a second generation data analysis technique such as SEM.

  3. Systematic analysis of a xenograft mice model for KSHV+ primary effusion lymphoma (PEL.

    Directory of Open Access Journals (Sweden)

    Lu Dai

    Full Text Available Kaposi's sarcoma-associated herpesvirus is the causative agent of primary effusion lymphoma (PEL, which arises preferentially in the setting of infection with human immunodeficiency virus (HIV. Even with standard cytotoxic chemotherapy, PEL continues to cause high mortality rates, requiring the development of novel therapeutic strategies. PEL xenograft models employing immunodeficient mice have been used to study the in vivo effects of a variety of therapeutic approaches. However, it remains unclear whether these xenograft models entirely reflect clinical presentations of KSHV(+ PEL, especially given the recent description of extracavitary solid tumor variants arising in patients. In addition, effusion and solid tumor cells propagated in vivo exhibit unique biology, differing from one another or from their parental cell lines propagated through in vitro culture. Therefore, we used a KSHV(+ PEL/BCBL-1 xenograft model involving non-obese diabetic/severe-combined immunodeficient (NOD/SCID mice, and compared characteristics of effusion and solid tumors with their parent cell culture-derived counterparts. Our results indicate that although this xenograft model can be used for study of effusion and solid lymphoma observed in patients, tumor cells in vivo display unique features to those passed in vitro, including viral lytic gene expression profile, rate of solid tumor development, the host proteins and the complex of tumor microenvironment. These items should be carefully considered when the xenograft model is used for testing novel therapeutic strategies against KSHV-related lymphoma.

  4. Hormone-induced rat model of polycystic ovary syndrome: A systematic review.

    Science.gov (United States)

    Noroozzadeh, Mahsa; Behboudi-Gandevani, Samira; Zadeh-Vakili, Azita; Ramezani Tehrani, Fahimeh

    2017-12-15

    Despite polycystic ovary syndrome (PCOS) being one of the most common endocrine disorders affecting reproductive-aged women, the etiopathogenesis and mechanisms of this syndrome remain unclear. Considering the ethical limitations in human studies, animal models that reflect many features of PCOS are crucial resources to investigate this syndrome. We aimed to introduce the most suitable rat model of PCOS that closely mimics the endocrine, ovarian and metabolic disturbances of human PCOS phenotype, while maintaining normal reproductive system morphology in adulthood, in order to further more detailed investigations about PCOS. We searched Pubmed, Science direct, and Web of science between 1990 and 2016, for relevant English manuscripts, using keywords including the "Polycystic Ovary Syndrome AND Rat Model" to generate a subset of citations relevant to our research. Included were those articles that compared at least both ovarian histology or estrous cycle and reproductive hormonal profiles in hormone-induced rat model of PCOS and controls. Differences in the findings between hormone-induced PCOS rats appear to be a result of the degree of transplacental transfer of the steroid administered into the fetus, dose and type of hormone, route of administration and timing and duration of exposure. We conclude that prenatal hormone-induced rat model with a lower dose and shorter time of exposure during the critical period of fetal development that exhibits endocrine, ovarian and metabolic disturbances similar to PCOS in women, while maintaining normal reproductive system morphology in adulthood is more suitable than postnatal hormone-induced rat model to facilitate studies regarding PCOS. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. The Effect of ISO 9001 and the EFQM Model on Improving Hospital Performance: A Systematic Review.

    Science.gov (United States)

    Yousefinezhadi, Taraneh; Mohamadi, Efat; Safari Palangi, Hossein; Akbari Sari, Ali

    2015-12-01

    This study aimed to explore the effect of the International Organization for Standardization (ISO) ISO 9001 standard and the European foundation for quality management (EFQM) model on improving hospital performance. PubMed, Embase and the Cochrane Library databases were searched. In addition, Elsevier and Springer were searched as main publishers in the field of health sciences. We included empirical studies with any design that had used ISO 9001 or the EFQM model to improve the quality of healthcare. Data were collected and tabulated into a data extraction sheet that was specifically designed for this study. The collected data included authors' names, country, year of publication, intervention, improvement aims, setting, length of program, study design, and outcomes. Seven out of the 121 studies that were retrieved met the inclusion criteria. Three studies assessed the EFQM model and four studies assessed the ISO 9001 standard. Use of the EFQM model increased the degree of patient satisfaction and the number of hospital admissions and reduced the average length of stay, the delay on the surgical waiting list, and the number of emergency re-admissions. ISO 9001 also increased the degree of patient satisfaction and patient safety, increased cost-effectiveness, improved the hospital admissions process, and reduced the percentage of unscheduled returns to the hospital. Generally, there is a lack of robust and high quality empirical evidence regarding the effects of ISO 9001 and the EFQM model on the quality care provided by and the performance of hospitals. However, the limited evidence shows that ISO 9001 and the EFQM model might improve hospital performance.

  6. Systematic studies of micro-channel plate tubes model PP0365G from Photonis

    CERN Document Server

    Castillo García, Lucía

    2013-01-01

    As part of the R&D phase of the TORCH (Time Of internally Reflected Cherenkov light) project, two micro-channel plate (MCP) photon detectors model PP0365G from Photonis have been characterized. The performance of each tube is shown. Timing properties of the tubes have been investigated with a pulsed laser diode in single photon regime. An excellent timing resolution of <40 ps is achieved. Back-scattering and laser light source effects are discussed. The corresponding results for Planacon tubes model XP85012/A1 from Photonis are given in appendix.

  7. Systematic study of baryons in a three-body quark model

    Science.gov (United States)

    Aslanzadeh, M.; Rajabi, A. A.

    2016-09-01

    We investigated the structure of baryons within a three-body quark model based on hypercentral approach. We considered an SU(6)-invariant potential consisting of the well-known "Coulomb-plus-linear" potential plus some multipole interactions as V ( x) ∝ x - n with n > 2. Then, through an analytical solution, we obtained the energy eigenvalues and eigenfunctions of the three-body problem and evaluated some observables such as the mass spectrum of light baryons and both the electromagnetic elastic form factors, and the charge radii of nucleons. We compared our results with the experimental data and showed that the present model provides a good description of the observed resonances.

  8. A more realistic estimate of the variances and systematic errors in spherical harmonic geomagnetic field models

    DEFF Research Database (Denmark)

    Lowes, F.J.; Olsen, Nils

    2004-01-01

    , led to quite inaccurate variance estimates. We estimate correction factors which range from 1/4 to 20, with the largest increases being for the zonal, m = 0, and sectorial, m = n, terms. With no correction, the OSVM variances give a mean-square vector field error of prediction over the Earth's surface......Most modern spherical harmonic geomagnetic models based on satellite data include estimates of the variances of the spherical harmonic coefficients of the model; these estimates are based on the geometry of the data and the fitting functions, and on the magnitude of the residuals. However...

  9. The attributes of the clinical trainer as a role model: a systematic review

    NARCIS (Netherlands)

    Jochemsen-van der Leeuw, H. G. A. Ria; van Dijk, Nynke; van Etten-Jamaludin, Faridi S.; Wieringa-de Waard, Margreet

    2013-01-01

    Medical trainees (interns and residents) and their clinical trainers need to be aware of the differences between positive and negative role modeling to ensure that trainees imitate and that trainers demonstrate the professional behavior required to provide high-quality patient care. The authors

  10. In-Service Training of Teachers in Multicultural Urban Schools: A Systematic Model.

    Science.gov (United States)

    Nickolai-Mays, Susanne; Davis, Jerry L.

    1986-01-01

    Presents seven guidelines for developing effective teacher in-service training programs. Describes a training model for multicultural urban schools which addresses these topics: instructional methods; curriculum; interpersonal relations in the classroom; classroom management and discipline; parent-teacher-student involvement; and multicultural…

  11. Anti-tumor effects of metformin in animal models of hepatocellular carcinoma: a systematic review and meta-analysis.

    Directory of Open Access Journals (Sweden)

    Juan Li

    Full Text Available Several studies have reported that metformin can reduce the risk of hepatocellular carcinoma (HCC in diabetes patients. However, the direct anti-HCC effects of metformin have hardly been studied in patients, but have been extensively investigated in animal models of HCC. We therefore performed a systematic review and meta-analysis of animal studies evaluating the effects of metformin on HCC.We collected the relevant studies by searching EMBASE, Medline (OvidSP, Web of Science, Scopus, PubMed Publisher, and Google Scholar. Studies were included according to the following inclusion criteria: HCC, animal study, and metformin intervention. Study quality was assessed using SYRCLE's risk of bias tool. A meta-analysis was performed for the outcome measures: tumor growth (tumor volume, weight and size, tumor number and incidence.The search resulted in 573 references, of which 13 could be included in the review and 12 included in the meta-analysis. The study characteristics of the included studies varied considerably. Two studies used rats, while the others used mice. Only one study used female animals, nine used male, and three studies didn't mention the gender of animals in their experiments. The quality of the included studies was low to moderate based on the assessment of their risk of bias. The meta-analysis showed that metformin significantly inhibited the growth of HCC tumour (SMD -2.20[-2.96,-1.43]; n=16, but no significant effect on the number of tumors (SMD-1.05[-2.13,0.03]; n=5 or the incidence of HCC was observed (RR 0.62[0.33,1.16]; n=6. To investigate the potential sources of significant heterogeneities found in outcome of tumor growth (I2=81%, subgroup analyses of scales of growth measures and of types of animal models used were performed.Metformin appears to have a direct anti-HCC effect in animal models. Although the intrinsic limitations of animal studies, this systematic review could provide an important reference for future

  12. Dermatologists across Europe underestimate depression and anxiety: results from 3635 dermatological consultations.

    Science.gov (United States)

    Dalgard, F J; Svensson, Å; Gieler, U; Tomas-Aragones, L; Lien, L; Poot, F; Jemec, G B E; Misery, L; Szabo, C; Linder, D; Sampogna, F; Evers, A W M; Anders Halvorsen, J; Balieva, F; Szepietowski, J; Lvov, A; Marron, S E; Alturnay, I K; Finlay, A Y; Salek, S S; Kupfer, J

    2017-12-16

    It was recently demonstrated that a significant number of patients with common skin diseases across Europe are clinically depressed and anxious. Studies have shown that physicians not trained as psychiatrist underdiagnose depression. This has not been explored among dermatologists. To estimate the concordance between clinical assessment of depression and anxiety by a dermatologist and assessment with the Hospital Anxiety and Depression Scale. The study was an observational cross-sectional multi-centre study of prevalent cases of skin diseases in 13 countries in Europe. Consecutive patients were recruited in out-patient clinics and filled in questionnaires prior to clinical examination by a dermatologist who reported any diagnosis of skin disease and signs of mood disorders. Analysis of the 3635 consultations showed that the agreement between dermatologist and HADS was poor to fair (lower than 0.4) for all diagnose categories. The true positive rate (represented by the percentage of dermatologists recognizing signs of depression or anxiety in depressed or anxious patients defined by HADS-value >=11) was 44.0% for depression and 35.6% for anxiety. The true negative rate (represented by the percentage of dermatologists not detecting signs of depression or anxiety in non-depressed or non-anxious patients defined byHADS-value < 11) was 56.0% for depression and 64.4% for anxiety. Dermatologists in Europe tend to underestimate mood disorders. The results point out that further training for dermatologists to improve their skills in diagnosing depression and anxiety might be appropriate. The psychological suffering of dermatological patients needs to be addressed when present. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  13. Reanalysis data underestimate significant changes in growing season weather in Kazakhstan

    International Nuclear Information System (INIS)

    Wright, C K; Henebry, G M; De Beurs, K M; Akhmadieva, Z K; Groisman, P Y

    2009-01-01

    We present time series analyses of recently compiled climate station data which allowed us to assess contemporary trends in growing season weather across Kazakhstan as drivers of a significant decline in growing season normalized difference vegetation index (NDVI) recently observed by satellite remote sensing across much of Central Asia. We used a robust nonparametric time series analysis method, the seasonal Kendall trend test to analyze georeferenced time series of accumulated growing season precipitation (APPT) and accumulated growing degree-days (AGDD). Over the period 2000-2006 we found geographically extensive, statistically significant (p<0.05) decreasing trends in APPT and increasing trends in AGDD. The temperature trends were especially apparent during the warm season and coincided with precipitation decreases in northwest Kazakhstan, indicating that pervasive drought conditions and higher temperature excursions were the likely drivers of NDVI declines observed in Kazakhstan over the same period. We also compared the APPT and AGDD trends at individual stations with results from trend analysis of gridded monthly precipitation data from the Global Precipitation Climatology Centre (GPCC) Full Data Reanalysis v4 and gridded daily near surface air temperature from the National Centers for Climate Prediction Reanalysis v2 (NCEP R2). We found substantial deviation between the station and the reanalysis trends, suggesting that GPCC and NCEP data substantially underestimate the geographic extent of recent drought in Kazakhstan. Although gridded climate products offer many advantages in ease of use and complete coverage, our findings for Kazakhstan should serve as a caveat against uncritical use of GPCC and NCEP reanalysis data and demonstrate the importance of compiling and standardizing daily climate data from data-sparse regions like Central Asia.

  14. An underestimated issue: unsuspected decrease of sound processor microphone sensitivity, technical, and clinical evaluation.

    Science.gov (United States)

    Razza, Sergio; Burdo, Sandro

    2011-05-01

    To describe the rate of occurrence of unsuspected decrease in sensitivity of the sound processor microphone and to evaluate its effect on the patient's audiological performance in terms of reduction in speech recognition scores. Speech processor microphones were tested by connecting the speech processor acoustic monitor circuit to a hearing aid analyzer. The response curves were compared with those obtained from fully working microphones. During a 6-month investigation period, microphone response curves were measured from a group of cochlear implant recipients who had not reported any problems. Despite the absence of any subjective problem, some microphones were found to show a loss of sensitivity. Their users, aged between 4 and 67 years, were tested both with the defective and a working microphone in order to calculate the correlation between the degree of microphone failure and the decline in audiological performance. To quantify the effect of microphone failure, patients' speech recognition skills were measured by live voice connected discourse tracking series administered in different conditions and by recorded sentences lists. A total of 120 apparently fully functioning sound processors were tested in the investigation: 33 (27.5%) were affected by a subjectively unreported sensitivity decrease. Speech-tracking scores correlated significantly with the loss of microphone sensitivity in all test conditions (r = 0.69-0.77, P processor microphone sensitivity causes a degree of hearing decline that negatively affects the cochlear recipient's clinical performance. Microphone faults are often unreported events, and their occurrence rate is underestimated. To establish that the microphone is providing correct input to the speech processor a standard control procedure, including technical and clinical checks, is needed in clinical practice.

  15. Seabird bycatch in pelagic longline fisheries is grossly underestimated when using only haul data.

    Directory of Open Access Journals (Sweden)

    Nigel Brothers

    Full Text Available Hundreds of thousands of seabirds are killed each year as bycatch in longline fisheries. Seabirds are predominantly caught during line setting but bycatch is generally recorded during line hauling, many hours after birds are caught. Bird loss during this interval may lead to inaccurate bycatch information. In this 15 year study, seabird bycatch was recorded during both line setting and line hauling from four fishing regions: Indian Ocean, Southern Ocean, Coral Sea and central Pacific Ocean. Over 43,000 albatrosses, petrels and skuas representing over 25 species were counted during line setting of which almost 6,000 seabirds attempted to take the bait. Bait-taking interactions were placed into one of four categories. (i The majority (57% of bait-taking attempts were "unsuccessful" involving seabirds that did not take the bait nor get caught or hooked. (ii One-third of attempts were "successful" with seabirds removing the bait while not getting caught. (iii One-hundred and seventy-six seabirds (3% of attempts were observed being "caught" during line setting, with three albatross species - Laysan (Phoebastria immutabilis, black-footed (P. nigripes and black-browed (Thalassarche melanophrys- dominating this category. However, of these, only 85 (48% seabird carcasses were retrieved during line hauling. Most caught seabirds were hooked through the bill. (iv The remainder of seabird-bait interactions (7% was not clearly observed, but likely involved more "caught" seabirds. Bait taking attempts and percentage outcome (e.g. successful, caught varied between seabird species and was not always related to species abundance around fishing vessels. Using only haul data to calculate seabird bycatch grossly underestimates actual bycatch levels, with the level of seabird bycatch from pelagic longline fishing possibly double what was previously thought.

  16. Standardized MET Value Underestimates the Energy Cost of Treadmill Running in Men.

    Science.gov (United States)

    Ázara, Helouane M; Farinatti, Paulo T V; Midgley, Adrian W; Vasconcellos, Fabrício; Vigário, Patrícia; Cunha, Felipe A

    2017-11-01

    The main purpose of the present study was to compare the reference metabolic equivalent (MET) value and observed resting oxygen uptake (VO 2 ) for defining cardiorespiratory fitness (VO 2max ) and characterizing the energy cost of treadmill running. A heterogeneous cohort of 114 healthy men volunteered to participate. In Part 1 of the study, 114 men [mean±SD, age: 24±5 years; height: 177.1±7.9 cm; body mass: 75.0±10.0 kg] visited the laboratory twice for assessment of resting and maximal VO 2 values to compare the reference MET value vs. observed resting VO 2 and to investigate the association between resting VO 2 and VO 2max . In Part 2, 14 of the 114 men visited the laboratory once more to perform a 30-min bout of running at 8.0 km∙h -1 /8.3 METs. The mean observed resting VO 2 of 3.26 mL·kg -1 ·min -1 was lower than the reference MET value of 3.5 mL·kg -1 ·min -1 (Pvalues relative to total body mass and fat-free mass were positively correlated (R=0.71 and 0.60, respectively; Pvalue only for those with low VO 2max (P=0.005 to Pvalue considerably overestimated observed resting VO 2 in men with low VO 2max , resulting in underestimations of the maximal MET, exercise intensity prescription, and the energy cost of running. © Georg Thieme Verlag KG Stuttgart · New York.

  17. Underestimation of homeless clients' interest in quitting smoking: a case for routine tobacco assessment.

    Science.gov (United States)

    Maddox, Sarah; Segan, Catherine

    2017-08-01

    Issue addressed In Australia smoking rates among the homeless are extremely high; however, little is known about their interest in quitting and few homeless services offer cessation assistance. In an Australian homeless service, this research examined the clients' smoking from the client, staff and organisational perspectives in order to assess the need for cessation assistance for clients and identify opportunities to increase access to it. Methods Twenty-six nurses completed an anonymous survey describing their attitudes to providing smoking-cessation support, current practices and estimates of client smoking and interest in quitting. Subsequently, nurses administered a survey to 104 clients to determine their smoking prevalence and interest in quitting. Organisation-wide tobacco-related policy and practices were audited. Results Most clients (82%) smoked, half of these (52%) reported wanting to quit and 64% reported trying to quit or reduce their smoking in the previous 3 months. Nurses approximated clients' smoking prevalence (88% vs 82% reported by clients), but underestimated interest in quitting (33% vs 52% reported by clients). Among nurses 93% agreed that cessation support should be part of normal client care. The organisation's client-assessment form contained fields for 'respiratory issues' and 'drug issues', but no specific field for smoking status. The organisation's smoking policy focused on providing a smoke-free work environment. Conclusions Many smokers using homeless services want to quit and are actively trying to reduce and quit smoking. Smoking-cessation assistance that meets the needs of people experiencing homelessness is clearly warranted. So what? Homeless services should develop, and include in their smoking policy and intake processes, a practice of routinely assessing tobacco use, offering brief interventions and referral to appropriately tailored services.

  18. On the underestimated impact of the gelation temperature on macro- and mesoporosity in monolithic silica.

    Science.gov (United States)

    Meinusch, Rafael; Ellinghaus, Rüdiger; Hormann, Kristof; Tallarek, Ulrich; Smarsly, Bernd M

    2017-06-07

    The preparation of monolithic SiO 2 with bimodal porosity using a special sol-gel procedure ("Nakanishi process") generally shows a pronounced sensitivity towards several physico-chemical parameters of the initial solution (concentrations, precursors, pH, temperature, etc.). Thus, temporal and spatial variations of these parameters during the sol-gel reactions can affect the final meso- and macropore space with respect to the pore size distributions and homogeneity. In this study we thoroughly examine the sol-gel reaction in terms of the impact of temperature accuracy and homogeneity during the gelation and their effect on meso- and macropore space. The in-depth characterization of the macroporosity in monolithic SiO 2 rods, prepared by utilizing a highly homogeneous and accurate temperature profile, shows that a decrease of only 1.5 °C during the reaction doubles the mean size of the macropores in the analyzed temperature ranges (22.0-28.0 °C and 33.5-36.5 °C). Rheological measurements of the gelation points and the viscosity of the starting solutions prove that a higher reaction rate is the main reason for this marked temperature-sensitivity. Furthermore, the mesoporosity is affected to a surprising extent by the applied small temperature differences during the gelation reaction. This phenomenon is shown to be mainly caused by the temperature-dependent differences in macropore and skeleton dimensions and an inhomogeneous distribution of mesopore sizes within the skeleton. In essence, our study reveals that the impact of temperature on the formation of meso- and macroscale dimensions during the sol-gel process has been underestimated so far. The impact of a poor temperature homogeneity during monolith synthesis is exemplarily demonstrated by the application of monolithic silica capillary columns in HPLC.

  19. Citation analysis may severely underestimate the impact of clinical research as compared to basic research.

    Science.gov (United States)

    van Eck, Nees Jan; Waltman, Ludo; van Raan, Anthony F J; Klautz, Robert J M; Peul, Wilco C

    2013-01-01

    Citation analysis has become an important tool for research performance assessment in the medical sciences. However, different areas of medical research may have considerably different citation practices, even within the same medical field. Because of this, it is unclear to what extent citation-based bibliometric indicators allow for valid comparisons between research units active in different areas of medical research. A visualization methodology is introduced that reveals differences in citation practices between medical research areas. The methodology extracts terms from the titles and abstracts of a large collection of publications and uses these terms to visualize the structure of a medical field and to indicate how research areas within this field differ from each other in their average citation impact. Visualizations are provided for 32 medical fields, defined based on journal subject categories in the Web of Science database. The analysis focuses on three fields: Cardiac & cardiovascular systems, Clinical neurology, and Surgery. In each of these fields, there turn out to be large differences in citation practices between research areas. Low-impact research areas tend to focus on clinical intervention research, while high-impact research areas are often more oriented on basic and diagnostic research. Popular bibliometric indicators, such as the h-index and the impact factor, do not correct for differences in citation practices between medical fields. These indicators therefore cannot be used to make accurate between-field comparisons. More sophisticated bibliometric indicators do correct for field differences but still fail to take into account within-field heterogeneity in citation practices. As a consequence, the citation impact of clinical intervention research may be substantially underestimated in comparison with basic and diagnostic research.

  20. Neglecting rice milling yield and quality underestimates economic losses from high-temperature stress.

    Directory of Open Access Journals (Sweden)

    Nathaniel B Lyman

    Full Text Available Future increases in global surface temperature threaten those worldwide who depend on rice production for their livelihoods and food security. Past analyses of high-temperature stress on rice production have focused on paddy yield and have failed to account for the detrimental impact of high temperatures on milling quality outcomes, which ultimately determine edible (marketable rice yield and market value. Using genotype specific rice yield and milling quality data on six common rice varieties from Arkansas, USA, combined with on-site, half-hourly and daily temperature observations, we show a nonlinear effect of high-temperature stress exposure on yield and milling quality. A 1 °C increase in average growing season temperature reduces paddy yield by 6.2%, total milled rice yield by 7.1% to 8.0%, head rice yield by 9.0% to 13.8%, and total milling revenue by 8.1% to 11.0%, across genotypes. Our results indicate that failure to account for changes in milling quality leads to understatement of the impacts of high temperatures on rice production outcomes. These dramatic losses result from reduced paddy yield and increased percentages of chalky and broken kernels, which together decrease the quantity and market value of milled rice. Recently published estimates show paddy yield reductions of up to 10% across the major rice-producing regions of South and Southeast Asia due to rising temperatures. The results of our study suggest that the often-cited 10% figure underestimates the economic implications of climate change for rice producers, thus potentially threatening future food security for global rice producers and consumers.

  1. The selection, optimization, and compensation model in the work context : A systematic review and meta-analysis of two decades of research

    NARCIS (Netherlands)

    Moghimi, Darya; Zacher, Hannes; Scheibe, Susanne; Van Yperen, Nico W.

    Over the past two decades, the selection, optimization, and compensation (SOC) model has been applied in the work context to investigate antecedents and outcomes of employees’ use of action regulation strategies. We systematically review, meta-analyze, and critically discuss the literature on SOC

  2. A systematic study of the low energy effects of heavy particles in the standard model

    International Nuclear Information System (INIS)

    Flores, E.V.

    1989-01-01

    In this approach, at any loop order, the low energy effects of a heavy Higgs boson and a heavy fermion can be summarized by an effective lagrangian. To the one-loop order, an effective lagrangian for the bosonic sector of the theory is constructed. One fermion mass is light (m) and the other is heavy (M). At the one-loop level heavy fermion mass effects proportional to M 2 and ln(M/m) have been found. It is shown here that in the presence of gauge fields, the infinities 1/ε of the nonlinear σ-model do not fully reproduce the ln(M H ) of the linear σ-model. (orig.)

  3. Using the Soil and Water Assessment Tool (SWAT) to model ecosystem services: A systematic review

    Science.gov (United States)

    Francesconi, Wendy; Srinivasan, Raghavan; Pérez-Miñana, Elena; Willcock, Simon P.; Quintero, Marcela

    2016-04-01

    SWAT, a watershed modeling tool has been proposed to help quantify ecosystem services. The concept of ecosystem services incorporates the collective benefits natural systems provide primarily to human beings. It is becoming increasingly important to track the impact that human activities have on the environment in order to determine its resilience and sustainability. The objectives of this paper are to provide an overview of efforts using SWAT to quantify ecosystem services, to determine the model's capability examining various types of services, and to describe the approach used by various researchers. A literature review was conducted to identify studies in which SWAT was explicitly used for quantifying ecosystem services in terms of provisioning, regulating, supporting, and cultural aspects. A total of 44 peer reviewed publications were identified. Most of these used SWAT to quantify provisioning services (34%), regulating services (27%), or a combination of both (25%). While studies using SWAT for evaluating ecosystem services are limited (approximately 1% of SWAT's peered review publications), and usage (vs. potential) of services by beneficiaries is a current model limitation, the available literature sets the stage for the continuous development and potential of SWAT as a methodological framework for quantifying ecosystem services to assist in decision-making.

  4. Effect of a high-fat diet and alcohol on cutaneous repair: A systematic review of murine experimental models.

    Directory of Open Access Journals (Sweden)

    Daiane Figueiredo Rosa

    Full Text Available Chronic alcohol intake associated with an inappropriate diet can cause lesions in multiple organs and tissues and complicate the tissue repair process. In a systematic review, we analyzed the relevance of alcohol and high fat consumption to cutaneous and repair, compared the main methodologies used and the most important parameters tested. Preclinical investigations with murine models were assessed to analyze whether the current evidence support clinical trials.The studies were selected from MEDLINE/PubMed and Scopus databases, according to Fig 1. All 15 identified articles had their data extracted. The reporting bias was investigated according to the ARRIVE (Animal Research: Reporting of in Vivo Experiments strategy.In general, animals offered a high-fat diet and alcohol showed decreased cutaneous wound closure, delayed skin contraction, chronic inflammation and incomplete re-epithelialization.In further studies, standardized experimental design is needed to establish comparable study groups and advance the overall knowledge background, facilitating data translatability from animal models to human clinical conditions.

  5. Comparison of effects of LLLT and LIPUS on fracture healing in animal models and patients: A systematic review.

    Science.gov (United States)

    Bayat, Mohammad; Virdi, Amarjit; Jalalifirouzkouhi, Reza; Rezaei, Fatemehalsadat

    2018-01-01

    The aim of this paper is to study the in vivo potency of low-level laser therapy (LLLT) and low intensity pulsed ultrasound (LIPUS) alone, accompanied by bone grafts, or accompanied by other factors on fracture healing in animal models and patients. In this paper, we aim to systematically review the published scientific literature regarding the use of LLLT and LIPUS to accelerate fracture healing in animal models and patients. We searched the PubMed database for the terms LLLT or LIPUS and/or bone, and fracture. Our analysis also suggests that both LIPUS and LLLT may be beneficial to fracture healing in patients, and that LIPUS is more effective. These finding are of considerable importance in those treatments with a LIPUS, as a laser device may reduce healing time. The most clinically relevant impact of the LIPUS treatment could be a significant reduction in the proportion of patients who go on to develop a nonunion. If it is confirmed that the therapeutic influence is true and reliable, patients will obtain benefits from LIPUS and LLLT. Further clinical trials of high methodological quality are needed in order to determine the optimal role of LIPUS and LLLT in fracture healing in patients. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Preclinical evaluation of cell-based strategies to prevent or treat bronchopulmonary dysplasia in animal models: a systematic review.

    Science.gov (United States)

    Lesage, Flore; Jimenez, Julio; Toelen, Jaan; Deprest, Jan

    2018-04-01

    Bronchopulmonary dysplasia (BPD) remains the most common complication of extreme prematurity as no effective treatment is available to date. This calls for the exploration of new therapeutic options like cell therapy, which is already effective for various human (lung) disorders. We systematically searched the MEDLINE, Embase, and Web of Science databases from the earliest date till January 2017 and included original studies on the perinatal use of cell-based therapies (i.e. cells and/or cell-derivatives) to treat BDP in animal models. Fourth publications describing 47 interventions were retrieved. Newborn mice/rats raised in a hyperoxic environment were studied in most interventions. Different cell types - either intact cells or their conditioned medium - were administered, but bone marrow and umbilical cord blood derived mesenchymal stem cells were most prevalent. All studies reported positive effects on outcome parameters including alveolar and vascular morphometry, lung function, and inflammation. Cell homing to the lungs was demonstrated in some studies, but the therapeutic effects seemed to be mostly mediated via paracrine modulation of inflammation, fibrosis and angiogenesis. Multiple rat/mouse studies show promise for cell therapy for BPD. Yet careful study of action mechanisms and side effects in large animal models is imperative before clinical translation can be achieved.

  7. Religion and Spirituality’s Influences on HIV Syndemics Among MSM: A Systematic Review and Conceptual Model

    Science.gov (United States)

    Parsons, Jeffrey T.

    2015-01-01

    This paper presents a systematic review of the quantitative HIV research that assessed the relationships between religion, spirituality, HIV syndemics, and individual HIV syndemics-related health conditions (e.g. depression, substance abuse, HIV risk) among men who have sex with men (MSM) in the United States. No quantitative studies were found that assessed the relationships between HIV syndemics, religion, and spirituality. Nine studies, with 13 statistical analyses, were found that examined the relationships between individual HIV syndemics-related health conditions, religion, and spirituality. Among the 13 analyses, religion and spirituality were found to have mixed relationships with HIV syndemics-related health conditions (6 nonsignificant associations; 5 negative associations; 2 positive associations). Given the overall lack of inclusion of religion and spirituality in HIV syndemics research, a conceptual model that hypothesizes the potential interactions of religion and spirituality with HIV syndemics-related health conditions is presented. The implications of the model for MSM’s health are outlined. PMID:26319130

  8. Animal-Assisted Therapies and Dementia: A Systematic Mapping Review Using the Lived Environment Life Quality (LELQ) Model.

    Science.gov (United States)

    Wood, Wendy; Fields, Beth; Rose, Michelle; McLure, Merinda

    The authors mapped the literature on animal-assisted therapies (AATs) and institutionalized adults with dementia onto the Lived Environment Life Quality (LELQ) Model as a guide for future services and research. Refereed literature addressing AATs and institutionalized people with dementia was comprehensively gathered, described, categorized, and synthesized in this systematic mapping review. From 1,342 screened records, the authors included 10 research articles that incorporated dogs in therapy for institutionalized adults with dementia. These canine-assisted therapies offered occupational opportunities and environmental supports conducive to experiences of relative well-being, occupational engagement, and optimal functioning. The findings offer proof of the concept that canine-assisted therapies are feasible and can elicit positive quality-of-life experiences in institutionalized people with dementia. Researchers and practitioners need to elucidate the theoretical foundations of AATs. The LELQ Model may serve as a guide for client-centered, occupation-focused, and ecologically valid approaches to animal-assisted occupational therapy. Copyright © 2017 by the American Occupational Therapy Association, Inc.

  9. How to Assess the External Validity and Model Validity of Therapeutic Trials: A Conceptual Approach to Systematic Review Methodology

    Science.gov (United States)

    2014-01-01

    Background. Evidence rankings do not consider equally internal (IV), external (EV), and model validity (MV) for clinical studies including complementary and alternative medicine/integrative medicine (CAM/IM) research. This paper describe this model and offers an EV assessment tool (EVAT©) for weighing studies according to EV and MV in addition to IV. Methods. An abbreviated systematic review methodology was employed to search, assemble, and evaluate the literature that has been published on EV/MV criteria. Standard databases were searched for keywords relating to EV, MV, and bias-scoring from inception to Jan 2013. Tools identified and concepts described were pooled to assemble a robust tool for evaluating these quality criteria. Results. This study assembled a streamlined, objective tool to incorporate for the evaluation of quality of EV/MV research that is more sensitive to CAM/IM research. Conclusion. Improved reporting on EV can help produce and provide information that will help guide policy makers, public health researchers, and other scientists in their selection, development, and improvement in their research-tested intervention. Overall, clinical studies with high EV have the potential to provide the most useful information about “real-world” consequences of health interventions. It is hoped that this novel tool which considers IV, EV, and MV on equal footing will better guide clinical decision making. PMID:24734111

  10. A systematic survey of the response of a model NF-κB signalling pathway to TNFα stimulation.

    Science.gov (United States)

    Wang, Yunjiao; Paszek, Pawel; Horton, Caroline A; Yue, Hong; White, Michael R H; Kell, Douglas B; Muldoon, Mark R; Broomhead, David S

    2012-03-21

    White's lab established that strong, continuous stimulation with tumour necrosis factor-α (TNFα) can induce sustained oscillations in the subcellular localisation of the transcription factor nuclear factor κB (NF-κB). But the intensity of the TNFα signal varies substantially, from picomolar in the blood plasma of healthy organisms to nanomolar in diseased states. We report on a systematic survey using computational bifurcation theory to explore the relationship between the intensity of TNFα stimulation and the existence of sustained NF-κB oscillations. Using a deterministic model developed by Ashall et al. in 2009, we find that the system's responses to TNFα are characterised by a supercritical Hopf bifurcation point: above a critical intensity of TNFα the system exhibits sustained oscillations in NF-kB localisation. For TNFα below this critical value, damped oscillations are observed. This picture depends, however, on the values of the model's other parameters. When the values of certain reaction rates are altered the response of the signalling pathway to TNFα stimulation changes: in addition to the sustained oscillations induced by high-dose stimulation, a second oscillatory regime appears at much lower doses. Finally, we define scores to quantify the sensitivity of the dynamics of the system to variation in its parameters and use these scores to establish that the qualitative dynamics are most sensitive to the details of NF-κB mediated gene transcription. Copyright © 2011 Elsevier Ltd. All rights reserved.

  11. Methodological quality and reporting of generalized linear mixed models in clinical medicine (2000-2012: a systematic review.

    Directory of Open Access Journals (Sweden)

    Martí Casals

    Full Text Available BACKGROUND: Modeling count and binary data collected in hierarchical designs have increased the use of Generalized Linear Mixed Models (GLMMs in medicine. This article presents a systematic review of the application and quality of results and information reported from GLMMs in the field of clinical medicine. METHODS: A search using the Web of Science database was performed for published original articles in medical journals from 2000 to 2012. The search strategy included the topic "generalized linear mixed models","hierarchical generalized linear models", "multilevel generalized linear model" and as a research domain we refined by science technology. Papers reporting methodological considerations without application, and those that were not involved in clinical medicine or written in English were excluded. RESULTS: A total of 443 articles were detected, with an increase over time in the number of articles. In total, 108 articles fit the inclusion criteria. Of these, 54.6% were declared to be longitudinal studies, whereas 58.3% and 26.9% were defined as repeated measurements and multilevel design, respectively. Twenty-two articles belonged to environmental and occupational public health, 10 articles to clinical neurology, 8 to oncology, and 7 to infectious diseases and pediatrics. The distribution of the response variable was reported in 88% of the articles, predominantly Binomial (n = 64 or Poisson (n = 22. Most of the useful information about GLMMs was not reported in most cases. Variance estimates of random effects were described in only 8 articles (9.2%. The model validation, the method of covariate selection and the method of goodness of fit were only reported in 8.0%, 36.8% and 14.9% of the articles, respectively. CONCLUSIONS: During recent years, the use of GLMMs in medical literature has increased to take into account the correlation of data when modeling qualitative data or counts. According to the current recommendations, the

  12. Forecasting Optimal Solar Energy Supply in Jiangsu Province (China: A Systematic Approach Using Hybrid of Weather and Energy Forecast Models

    Directory of Open Access Journals (Sweden)

    Xiuli Zhao

    2014-01-01

    Full Text Available The idea of aggregating information is clearly recognizable in the daily lives of all entities whether as individuals or as a group, since time immemorial corporate organizations, governments, and individuals as economic agents aggregate information to formulate decisions. Energy planning represents an investment-decision problem where information needs to be aggregated from credible sources to predict both demand and supply of energy. To do this there are varying methods ranging from the use of portfolio theory to managing risk and maximizing portfolio performance under a variety of unpredictable economic outcomes. The future demand for energy and need to use solar energy in order to avoid future energy crisis in Jiangsu province in China require energy planners in the province to abandon their reliance on traditional, “least-cost,” and stand-alone technology cost estimates and instead evaluate conventional and renewable energy supply on the basis of a hybrid of optimization models in order to ensure effective and reliable supply. Our task in this research is to propose measures towards addressing optimal solar energy forecasting by employing a systematic optimization approach based on a hybrid of weather and energy forecast models. After giving an overview of the sustainable energy issues in China, we have reviewed and classified the various models that existing studies have used to predict the influences of the weather influences and the output of solar energy production units. Further, we evaluate the performance of an exemplary ensemble model which combines the forecast output of two popular statistical prediction methods using a dynamic weighting factor.

  13. Forecasting optimal solar energy supply in Jiangsu Province (China): a systematic approach using hybrid of weather and energy forecast models.

    Science.gov (United States)

    Zhao, Xiuli; Asante Antwi, Henry; Yiranbon, Ethel

    2014-01-01

    The idea of aggregating information is clearly recognizable in the daily lives of all entities whether as individuals or as a group, since time immemorial corporate organizations, governments, and individuals as economic agents aggregate information to formulate decisions. Energy planning represents an investment-decision problem where information needs to be aggregated from credible sources to predict both demand and supply of energy. To do this there are varying methods ranging from the use of portfolio theory to managing risk and maximizing portfolio performance under a variety of unpredictable economic outcomes. The future demand for energy and need to use solar energy in order to avoid future energy crisis in Jiangsu province in China require energy planners in the province to abandon their reliance on traditional, "least-cost," and stand-alone technology cost estimates and instead evaluate conventional and renewable energy supply on the basis of a hybrid of optimization models in order to ensure effective and reliable supply. Our task in this research is to propose measures towards addressing optimal solar energy forecasting by employing a systematic optimization approach based on a hybrid of weather and energy forecast models. After giving an overview of the sustainable energy issues in China, we have reviewed and classified the various models that existing studies have used to predict the influences of the weather influences and the output of solar energy production units. Further, we evaluate the performance of an exemplary ensemble model which combines the forecast output of two popular statistical prediction methods using a dynamic weighting factor.

  14. Assessment of perioperative stress in colorectal cancer by use of in vitro cell models: a systematic review

    Directory of Open Access Journals (Sweden)

    Tove Kirkegaard

    2017-11-01

    Full Text Available Background The perioperative period is important for patient outcome. Colorectal cancer surgery can lead to metastatic disease due to release of disseminated tumor cells and the induction of surgical stress response. To explore the overall effects on surgically-induced changes in serum composition, in vitro model systems are useful. Methods A systematic search in PubMed and EMBASE was performed to identify studies describing in vitro models used to investigate cancer cell growth/proliferation, cell migration, cell invasion and cell death of serum taken pre- and postoperatively from patients undergoing colorectal tumor resection. Results Two authors (MG and TK independently reviewed 984 studies and identified five studies, which fulfilled the inclusion criteria. Disagreements were solved by discussion. All studies investigated cell proliferation and cell invasion, whereas three studies investigated cell migration, and only one study investigated cell death/apoptosis. One study investigated postoperative peritoneal infection due to anastomotic leak, one study investigated mode of anesthesia (general anesthesia with volatile or intravenous anesthetics, and one study investigated preoperative intervention with granulocyte macrophage colony stimulating factor (GMCSF. In all studies an increased proliferation, cell migration and invasion was demonstrated after surgery. Anesthetics with propofol and intervention with GMCSF significantly reduced postoperative cell proliferation, whereas peritoneal infection enhanced the invasive capability of tumor cells. Conclusion This study suggests that in vitro cell models are useful and reliable tools to explore the effect of surgery on colorectal cancer cell proliferation and metastatic ability. The models should therefore be considered as additional tests to investigate the effects of perioperative interventions.

  15. Model-based economic evaluations in smoking cessation and their transferability to new contexts: a systematic review.

    Science.gov (United States)

    Berg, Marrit L; Cheung, Kei Long; Hiligsmann, Mickaël; Evers, Silvia; de Kinderen, Reina J A; Kulchaitanaroaj, Puttarin; Pokhrel, Subhash

    2017-06-01

    To identify different types of models used in economic evaluations of smoking cessation, analyse the quality of the included models examining their attributes and ascertain their transferability to a new context. A systematic review of the literature on the economic evaluation of smoking cessation interventions published between 1996 and April 2015, identified via Medline, EMBASE, National Health Service (NHS) Economic Evaluation Database (NHS EED), Health Technology Assessment (HTA). The checklist-based quality of the included studies and transferability scores was based on the European Network of Health Economic Evaluation Databases (EURONHEED) criteria. Studies that were not in smoking cessation, not original research, not a model-based economic evaluation, that did not consider adult population and not from a high-income country were excluded. Among the 64 economic evaluations included in the review, the state-transition Markov model was the most frequently used method (n = 30/64), with quality adjusted life years (QALY) being the most frequently used outcome measure in a life-time horizon. A small number of the included studies (13 of 64) were eligible for EURONHEED transferability checklist. The overall transferability scores ranged from 0.50 to 0.97, with an average score of 0.75. The average score per section was 0.69 (range = 0.35-0.92). The relative transferability of the studies could not be established due to a limitation present in the EURONHEED method. All existing economic evaluations in smoking cessation lack in one or more key study attributes necessary to be fully transferable to a new context. © 2017 The Authors. Addiction published by John Wiley & Sons Ltd on behalf of Society for the Study of Addiction.

  16. Efficacy of Mesenchymal Stromal Cell Therapy for Acute Lung Injury in Preclinical Animal Models: A Systematic Review.

    Directory of Open Access Journals (Sweden)

    Lauralyn A McIntyre

    Full Text Available The Acute Respiratory Distress Syndrome (ARDS is a devastating clinical condition that is associated with a 30-40% risk of death, and significant long term morbidity for those who survive. Mesenchymal stromal cells (MSC have emerged as a potential novel treatment as in pre-clinical models they have been shown to modulate inflammation (a major pathophysiological hallmark of ARDS while enhancing bacterial clearance and reducing organ injury and death. A systematic search of MEDLINE, EMBASE, BIOSIS and Web of Science was performed to identify pre-clinical studies that examined the efficacy MSCs as compared to diseased controls for the treatment of Acute Lung Injury (ALI (the pre-clinical correlate of human ARDS on mortality, a clinically relevant outcome. We assessed study quality and pooled results using random effect meta-analysis. A total of 54 publications met our inclusion criteria of which 17 (21 experiments reported mortality and were included in the meta-analysis. Treatment with MSCs, as compared to controls, significantly decreased the overall odds of death in animals with ALI (Odds Ratio 0.24, 95% Confidence Interval 0.18-0.34, I2 8%. Efficacy was maintained across different types of animal models and means of ALI induction; MSC origin, source, route of administration and preparation; and the clinical relevance of the model (timing of MSC administration, administration of fluids and or antibiotics. Reporting of standard MSC characterization for experiments that used human MSCs and risks of bias was generally poor, and although not statistically significant, a funnel plot analysis for overall mortality suggested the presence of publication bias. The results from our meta-analysis support that MSCs substantially reduce the odds of death in animal models of ALI but important reporting elements were sub optimal and limit the strength of our conclusions.

  17. Systematic investigation on the turning point of over-inflammation to immunosuppression in CLP mice model and their characteristics.

    Science.gov (United States)

    Deng, Dongmei; Li, Xiaoli; Liu, Chao; Zhai, Zhaoxia; Li, Bin; Kuang, Mei; Li, Pan; Shang, Shenglan; Song, Yi; Cen, Yanyan; Qin, Rongxin; Lu, Yonglin; Zhao, Yibo; Cheng, Hao; Zheng, Jiang; Zhou, Hong

    2017-01-01

    Immunosuppression is involved in refractory innate and adaptive immune responses and is considered to be the predominant driving force for mortality in sepsis. The cecal ligation and puncture (CLP) model is regarded as a golden standard model for sepsis study, but the turning point of over-inflammation to immunosuppression was reported differently. Herein, systematic investigation on the turning point of over-inflammation to immunosuppression in CLP mice model was carried out. The results showed only the mortality of mice challenged with of Pseudomonas aeruginosa on Day 1 not other days after the surgery was higher than that of other mice with Sham surgery, suggesting Day 1 after the CLP surgery might be the turning point. There was very low mortality even without death in Sham mice but the mortality was 80% after mice were challenged with 2.5×10 7 , 5.0×10 6 and 1.0×10 6 CFU/10g of Pseudomonas aeruginosa, further demonstrating Day 1 after the CLP surgery was the turning point. And, CLP mice presented low levels of pro-inflammatory and anti-inflammatory cytokines, and high bacterial loads on Day 1. Additionally, the amounts and proportion of blood cells and monocytes significantly changed, too. In conclusion, Day 1 after the CLP surgery was the turning point of over-inflammation to immunosuppression, and low levels of cytokines and high bacterial loads were the characteristics of this model on Day 1, which is significant for pharmacological investigation on sepsis. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Alveolar bone tissue engineering in critical-size defects of experimental animal models: a systematic review and meta-analysis.

    Science.gov (United States)

    Shanbhag, Siddharth; Pandis, Nikolaos; Mustafa, Kamal; Nyengaard, Jens R; Stavropoulos, Andreas

    2017-10-01

    Regeneration of large, 'critical-size' bone defects remains a clinical challenge. Bone tissue engineering (BTE) is emerging as a promising alternative to autogenous, allogeneic and biomaterial-based bone grafting. The objective of this systematic review was to answer the focused question: in animal models, do cell-based BTE strategies enhance regeneration in alveolar bone critical-size defects (CSDs), compared with grafting with only biomaterial scaffolds or autogenous bone? Following PRISMA guidelines, electronic databases were searched for controlled animal studies reporting maxillary or mandibular CSD and implantation of mesenchymal stem cells (MSCs) or osteoblasts (OBs) seeded on biomaterial scaffolds. A random effects meta-analysis was performed for the outcome histomorphometric new bone formation (%NBF). Thirty-six studies were included that reported on large- (monkeys, dogs, sheep, minipigs) and small-animal (rabbits, rats) models. On average, studies presented with an unclear-to-high risk of bias and short observation times. In most studies, MSCs or OBs were used in combination with alloplastic mineral-phase scaffolds. In five studies, cells were modified by ex vivo gene transfer of bone morphogenetic proteins (BMPs). The meta-analysis indicated statistically significant benefits in favour of: (1) cell-loaded vs. cell-free scaffolds [weighted mean difference (WMD) 15.59-49.15% and 8.60-13.85% NBF in large- and small-animal models, respectively]; and (2) BMP-gene-modified vs. unmodified cells (WMD 10.06-20.83% NBF in small-animal models). Results of cell-loaded scaffolds vs. autogenous bone were inconclusive. Overall, heterogeneity in the meta-analysis was high (I 2  > 90%). In summary, alveolar bone regeneration is enhanced by addition of osteogenic cells to biomaterial scaffolds. The direction and estimates of treatment effect are useful to predict therapeutic efficacy and guide future clinical trials of BTE. Copyright © 2016 John Wiley & Sons, Ltd

  19. Telehealth in Schools Using a Systematic Educational Model Based on Fiction Screenplays, Interactive Documentaries, and Three-Dimensional Computer Graphics.

    Science.gov (United States)

    Miranda, Diogo Julien; Chao, Lung Wen

    2018-03-01

    Preliminary studies suggest the need of a global vision in academic reform, leading to education re-invention. This would include problem-based education using transversal topics, developing of thinking skills, social interaction, and information-processing skills. We aimed to develop a new educational model in health with modular components to be broadcast and applied as a tele-education course. We developed a systematic model based on a "Skills and Goals Matrix" to adapt scientific contents on fictional screenplays, three-dimensional (3D) computer graphics of the human body, and interactive documentaries. We selected 13 topics based on youth vulnerabilities in Brazil to be disseminated through a television show with 15 episodes. We developed scientific content for each theme, naturally inserting it into screenplays, together with 3D sequences and interactive documentaries. The modular structure was then adapted to a distance-learning course. The television show was broadcast on national television for two consecutive years to an estimated audience of 30 million homes, and ever since on an Internet Protocol Television (IPTV) channel. It was also reorganized as a tele-education course for 2 years, reaching 1,180 subscriptions from all 27 Brazilian states, resulting in 240 graduates. Positive results indicate the feasibility, acceptability, and effectiveness of a model of modular entertainment audio-visual productions using health and education integrated concepts. This structure also allowed the model to be interconnected with other sources and applied as tele-education course, educating, informing, and stimulating the behavior change. Future works should reinforce this joint structure of telehealth, communication, and education.

  20. Disguised Distress in Children and Adolescents "Flying under the Radar": Why Psychological Problems Are Underestimated and How Schools Must Respond

    Science.gov (United States)

    Flett, Gordon L.; Hewitt, Paul L.

    2013-01-01

    It is now recognized that there is a very high prevalence of psychological disorders among children and adolescents and relatively few receive psychological treatment. In the current article, we present the argument that levels of distress and dysfunction among young people are substantially underestimated and the prevalence of psychological…

  1. Non-differential underestimation may cause a threshold effect of exposure to appear as a dose-response relationship

    NARCIS (Netherlands)

    Verkerk, P. H.; Buitendijk, S. E.

    1992-01-01

    It is generally believed that non-differential misclassification will lead to a bias toward the null-value. However, using one graphical and one numerical example, we show that in situations where underestimation more than overestimation is the problem, non-differential misclassification may lead to

  2. Accuracy and bias of ICT self-efficacy: an empirical study into students' over- and underestimation of their ICT competences

    NARCIS (Netherlands)

    Aesaert, K.; Voogt, J.; Kuiper, E.; van Braak, J.

    2017-01-01

    Most studies on the assessment of ICT competences use measures of ICT self-efficacy. These studies are often accused that they suffer from self-reported bias, i.e. students can over- and/or underestimate their ICT competences. As such, taking bias and accuracy of ICT self-efficacy into account,

  3. Underestimates of sensible heat flux due to vertical velocity measurement errors in non-orthogonal sonic anemometers

    Science.gov (United States)

    John M. Frank; William J. Massman; Brent E. Ewers

    2013-01-01

    Sonic thermometry and anemometry are fundamental to all eddy-covariance studies of surface energy balance. Recent studies have suggested that sonic anemometers with non-orthogonal transducers can underestimate vertical wind velocity (w) and sensible heat flux (H) when compared to orthogonal designs. In this study we tested whether a non-orthogonal sonic anemometer (...

  4. Distorted self-perceived weight status and underestimation of weight status in diabetes mellitus type 2 patients.

    Directory of Open Access Journals (Sweden)

    Victor Mogre

    Full Text Available OBJECTIVES: Diabetes mellitus type 2 (DM 2 patients' self-perception of their weight status is very critical in diabetes care. We sought to investigate perception of weight status in a sample of 200 DM 2 patients attending an outpatient clinic at a Teaching Hospital and compared it with their BMI-measured weight status, with a focus on underestimation of their weight status. Factors associated with underestimation of weight status in this sample were also explored. METHODS: Using a cross-sectional design, anthropometric and clinical variables were assessed using appropriate tools. Questionnaires were used to collect socio-demographic data and self-perception of weight status. Self-perceived weight status was compared to BMI-measured weight status by cross-tabulation, Kappa statistics of agreement and χ2 for trend analysis. Both univariate and multiple logistic regression analysis were conducted to identify factors associated with underestimation of weight status. RESULTS: The prevalence of general overweight/obesity and abdominal obesity was 32.0% (n = 64 and 58.0% (n = 116 respectively. Generally, 58.0% (n = 116 of the participants had a distorted weight perceived weight status in which 77.6% (n = 90 underestimated their weight status. Factors associated with underestimation of weight status were being overweight/obese (AOR = 22.9, 95% CI = 8.30-63.07, p<0.001, not married (AOR = 3.7, 95% CI = 1.50-9.17, p = 0.005 and never tried to lose weight (AOR = 6.9, 95% CI = 2.35-19.97, p<0.001. Participants aged over 40 years and those being hyperglycaemic were not significantly associated to underestimation of weight status. CONCLUSION: We found a substantial discordance between BMI-measured and self-perceived weight status. Factors that were associated with underestimation of weight status were being; overweight/obese, not married and never tried to lose weight. Diabetes patients should be provided with

  5. Regularities in hadron systematics, Regge trajectories and a string quark model

    International Nuclear Information System (INIS)

    Chekanov, S.V.; Levchenko, B.B.

    2006-08-01

    An empirical principle for the construction of a linear relationship between the total angular momentum and squared-mass of baryons is proposed. In order to examine linearity of the trajectories, a rigorous least-squares regression analysis was performed. Unlike the standard Regge-Chew-Frautschi approach, the constructed trajectories do not have non-linear behaviour. A similar regularity may exist for lowest-mass mesons. The linear baryonic trajectories are well described by a semi-classical picture based on a spinning relativistic string with tension. The obtained numerical solution of this model was used to extract the (di)quark masses. (orig.)

  6. On underestimation of global vulnerability to tree mortality and forest die-off from hotter drought in the Anthropocene

    Science.gov (United States)

    Allen, Craig D.; Breshears, David D.; McDowell, Nathan G.

    2015-01-01

    Patterns, mechanisms, projections, and consequences of tree mortality and associated broad-scale forest die-off due to drought accompanied by warmer temperatures—“hotter drought”, an emerging characteristic of the Anthropocene—are the focus of rapidly expanding literature. Despite recent observational, experimental, and modeling studies suggesting increased vulnerability of trees to hotter drought and associated pests and pathogens, substantial debate remains among research, management and policy-making communities regarding future tree mortality risks. We summarize key mortality-relevant findings, differentiating between those implying lesser versus greater levels of vulnerability. Evidence suggesting lesser vulnerability includes forest benefits of elevated [CO2] and increased water-use efficiency; observed and modeled increases in forest growth and canopy greening; widespread increases in woody-plant biomass, density, and extent; compensatory physiological, morphological, and genetic mechanisms; dampening ecological feedbacks; and potential mitigation by forest management. In contrast, recent studies document more rapid mortality under hotter drought due to negative tree physiological responses and accelerated biotic attacks. Additional evidence suggesting greater vulnerability includes rising background mortality rates; projected increases in drought frequency, intensity, and duration; limitations of vegetation models such as inadequately represented mortality processes; warming feedbacks from die-off; and wildfire synergies. Grouping these findings we identify ten contrasting perspectives that shape the vulnerability debate but have not been discussed collectively. We also present a set of global vulnerability drivers that are known with high confidence: (1) droughts eventually occur everywhere; (2) warming produces hotter droughts; (3) atmospheric moisture demand increases nonlinearly with temperature during drought; (4) mortality can occur faster in

  7. Flavonoids Effects on Hepatocellular Carcinoma in Murine Models: A Systematic Review

    Directory of Open Access Journals (Sweden)

    Estefanny Ruiz García

    2018-01-01

    Full Text Available The hepatocellular carcinoma (HCC is the second most common cause of cancer deaths worldwide. It occurs primarily as manifestation of other pathological processes, such as viral hepatitis, cirrhosis, and toxin exposure that affect directly the cellular process. Studies were selected from PubMed and Scopus databases according to the PRISMA statement. The research filters were constructed using three parameters: flavonoids, hepatocellular carcinoma, and animal model. The bias analysis of the 34 selected works was done using the ARRIVE guidelines. The most widely used flavonoid in the studies was epigallocatechin gallate extracted from green tea. In general, the treatment with different flavonoids presented inhibition of tumor growth and antiangiogenic, antimetastatic, antioxidant, and anti-inflammatory activities. The bias analysis evidenced the absence of methodological processes in all studies, such as the age or weight of the animals, the method of flavonoids’ extraction, or the experimental designs, analytical methods, and outcome measures. It has been known that flavonoids have a protective effect against HCC. However, the absence or incomplete characterization of the animal models, treatment protocols, and phytochemical and toxicity analyses impaired the internal validity of the individual studies, making it difficult to determine the effectiveness of plant-derived products in the treatment of HCC.

  8. Towards Systematic Prediction of Urban Heat Islands: Grounding Measurements, Assessing Modeling Techniques

    Directory of Open Access Journals (Sweden)

    Jackson Voelkel

    2017-06-01

    Full Text Available While there exists extensive assessment of urban heat, we observe myriad methods for describing thermal distribution, factors that mediate temperatures, and potential impacts on urban populations. In addition, the limited spatial and temporal resolution of satellite-derived heat measurements may limit the capacity of decision makers to take effective actions for reducing mortalities in vulnerable populations whose locations require highly-refined measurements. Needed are high resolution spatial and temporal information for urban heat. In this study, we ask three questions: (1 how do urban heat islands vary throughout the day? (2 what statistical methods best explain the presence of temperatures at sub-meter spatial scales; and (3 what landscape features help to explain variation in urban heat islands? Using vehicle-based temperature measurements at three periods of the day in the Pacific Northwest city of Portland, Oregon (USA, we incorporate LiDAR-derived datasets, and evaluate three statistical techniques for modeling and predicting variation in temperatures during a heat wave. Our results indicate that the random forest technique best predicts temperatures, and that the evening model best explains the variation in temperature. The results suggest that ground-based measurements provide high levels of accuracy for describing the distribution of urban heat, its temporal variation, and specific locations where targeted interventions with communities can reduce mortalities from heat events.

  9. Emotion regulation model in binge eating disorder and obesity--a systematic review.

    Science.gov (United States)

    Leehr, Elisabeth J; Krohmer, Kerstin; Schag, Kathrin; Dresler, Thomas; Zipfel, Stephan; Giel, Katrin E

    2015-02-01

    Deficits in emotion regulation processes are a common and widely used explanation for the development and maintenance of binge eating disorder (BED). It is assumed that BED patients - as they have difficulty regulating their negative emotions - use binge eating to cope with these emotions and to find relief. However, the number of experimental studies investigating this assumption is scarce and the differentiation of obese individuals with and without BED regarding the emotion regulation model is not verified. We reviewed literature for experimental studies investigating the emotion regulation model in obese patients (OB) with and without BED. Our search resulted in 18 experimental studies examining the triggering effect of negative emotions for binge eating or its effects on subsequent relief. We found evidence indicating that negative emotion serves as a trigger for binge eating in the BED group unlike the obese group without BED. Considering the small number of studies, we found evidence for a (short-term) improvement of mood through food intake, irrespective of group. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Essential value of cocaine and food in rats: tests of the exponential model of demand.

    Science.gov (United States)

    Christensen, Chesley J; Silberberg, Alan; Hursh, Steven R; Huntsberry, Mary E; Riley, Anthony L

    2008-06-01

    To provide a prospective test of the predictive adequacy of the exponential model of demand (Hursh and Silberberg, Psych Rev 115(1):186-198, 2008). In Experiment 1, to measure the 'essential value' (the propensity to defend consumption with changes in price) of cocaine and food in a demand analysis (functional relation between price and consumption) by means of the exponential model; in Experiment 2, to test whether the model's systematic underestimation of cocaine consumption in Experiment 1 was due to weight loss; and in Experiment 3, to evaluate the effects of cocaine on the essential value of food. In Experiment 1, demand curves for food and cocaine were determined by measuring consumption of these goods in a multiple schedule over a range of fixed ratios; in Experiment 2, a demand curve for only cocaine was determined; and in Experiment 3, demand for food was determined in the absence of cocaine. In Experiment 1, the exponential equation accommodated high portions of variance for both curves, but systematically underestimated cocaine demand; in Experiment 2, this predictive underestimation of the equation was eliminated; and in Experiment 3, the essential value of food was greater than in Experiment 1. The exponential model of demand accommodated the data variance for all cocaine and food demand curves. Compared to food, cocaine is a good of lower essential value.

  11. [A model of world population growth as an experiment in systematic research].

    Science.gov (United States)

    Kapitsa, S

    1997-01-01

    A mathematical model was developed for the estimation of global population growth, and the estimates were compared with those of the UN and covered the stretch of 4.4 million years B.C. to the years 2175 and 2500 A.D. The estimates were also broken down into human, geological, and technological historical periods. The model showed that human population would stabilize at the level of 14 billion around 2500 A.D. and 13 billion around 2200 A.D., in accordance with UN projections. It also revealed the history of human population growth through the following stages (UN figures are listed in parentheses): 100,000, about 1.6 million years ago; 5 (1-5) million, 35,000 B.C.; 21 (10-15) million, 7000 B.C.; 46 (47) million, 2000 B.C.; 93 (100-230) million, at the time of Christ; 185 (275-345) million, 1000 A.D.; 366 (450-540) million, 1500 A.D.; 887 (907) million, 1800 A.D.; 1158 (1170) million, 1850 A.D.; 1656 (1650-1710) million, 1900 A.D.; 2812 (2515) million, 1950 A.D.; 5253 (5328) million, 1990 A.D.; 6265 (6261) million, 2000 A.D.; 10,487 (10,019) million, 2050 A.D.; 12,034 (11,186) million, 2100 A.D.; 12,648 (11,543) million, 2150 A.D.; 12,946 (11,600) million, 2200 A.D.; and 13,536 million, 2500 A.D. The model advanced the investigation of phenomena by studying the interactions between economical, technological, social, cultural, and biological processes. The analysis showed that humanity has reached a critical phase in its growth and that development in each period depended on external, not internal, factors. This permits the formulation of the principle of demographic imperative (distinct from the Malthusian principle), which states that resources determine the speed and extent of the growth of population.

  12. Systematic synergy modeling: understanding drug synergy from a systems biology perspective.

    Science.gov (United States)

    Chen, Di; Liu, Xi; Yang, Yiping; Yang, Hongjun; Lu, Peng

    2015-09-16

    Owing to drug synergy effects, drug combinations have become a new trend in combating complex diseases like cancer, HIV and cardiovascular diseases. However, conventional synergy quantification methods often depend on experimental dose-response data which are quite resource-demanding. In addition, these methods are unable to interpret the explicit synergy mechanism. In this review, we give representative examples of how systems biology modeling offers strategies toward better understanding of drug synergy, including the protein-protein interaction (PPI) network-based methods, pathway dynamic simulations, synergy network motif recognitions, integrative drug feature calculations, and "omic"-supported analyses. Although partially successful in drug synergy exploration and interpretation, more efforts should be put on a holistic understanding of drug-disease interactions, considering integrative pharmacology and toxicology factors. With a comprehensive and deep insight into the mechanism of drug synergy, systems biology opens a novel avenue for rational design of effective drug combinations.

  13. Modelling systematics of ground-based transit photometry I. Implications on transit timing variations

    DEFF Research Database (Denmark)

    von Essen, C.; Cellone, S.; Mallonn, M.

    2016-01-01

    The transit timing variation technique (TTV) has been widely used to detect and characterize multiple planetary systems. Due to the observational biases imposed mainly by the photometric conditions and instrumentation and the high signal-to-noise required to produce primary transit observations...... the observing time at hand carrying out such follow-ups, or if the use of medium-to-low quality transit light curves, combined with current standard techniques of data analysis, could be playing a main role against exoplanetary search via TTVs. The purpose of this work is to investigate to what extent ground......-based observations treated with current modelling techniques are reliable to detect and characterize additional planets in already known planetary systems. To meet this goal, we simulated typical primary transit observations of a hot Jupiter mimicing an existing system, Qatar-1. To resemble ground-based observations...

  14. Associations between psychological variables and pain in experimental pain models. A systematic review

    DEFF Research Database (Denmark)

    Hansen, M S; Horjales-Araujo, E; Dahl, J B

    2015-01-01

    in healthy volunteers were considered for inclusion. RESULTS: Twenty-nine trials met the inclusion criteria, with a total of 2637 healthy volunteers. The included trials investigated a total of 45 different psychological tests and 27 different types of pain models. The retrieved trials did not present......BACKGROUND: The association between pain and psychological characteristics has been widely debated. Thus, it remains unclear whether an individual's psychological profile influences a particular pain experience, or if previous pain experience contributes to a certain psychological profile....... Translational studies performed in healthy volunteers may provide knowledge concerning psychological factors in healthy individuals as well as basic pain physiology. The aim of this review was to investigate whether psychological vulnerability or specific psychological variables in healthy volunteers...

  15. Porcine familial adenomatous polyposis model enables systematic analysis of early events in adenoma progression.

    Science.gov (United States)

    Flisikowska, Tatiana; Stachowiak, Monika; Xu, Hongen; Wagner, Alexandra; Hernandez-Caceres, Alejandra; Wurmser, Christine; Perleberg, Carolin; Pausch, Hubert; Perkowska, Anna; Fischer, Konrad; Frishman, Dmitrij; Fries, Ruedi; Switonski, Marek; Kind, Alexander; Saur, Dieter; Schnieke, Angelika; Flisikowski, Krzysztof

    2017-07-26

    We compared gene expression in low and high-grade intraepithelial dysplastic polyps from pigs carrying an APC 1311 truncating mutation orthologous to human APC 1309 , analysing whole samples and microdissected dysplastic epithelium. Gene set enrichment analysis revealed differential expression of gene sets similar to human normal mucosa versus T1 stage polyps. Transcriptome analysis of whole samples revealed many differentially-expressed genes reflecting immune infiltration. Analysis of microdissected dysplastic epithelium was markedly different and showed increased expression in high-grade intraepithelial neoplasia of several genes known to be involved in human CRC; and revealed possible new roles for GBP6 and PLXND1. The pig model thus facilitates analysis of CRC pathogenesis.

  16. Health service delivery models for the provision of antiretroviral therapy in sub-Saharan Africa: a systematic review.

    Science.gov (United States)

    Lazarus, Jeffrey V; Safreed-Harmon, Kelly; Nicholson, Joey; Jaffar, Shabbar

    2014-10-01

    In response to the lack of evidence-based guidance for how to continue scaling up antiretroviral therapy (ART) in ways that make optimal use of limited resources, to assess comparative studies of ART service delivery models implemented in sub-Saharan Africa. A systematic literature search and analysis of studies that compared two or more methods of ART service delivery using either CD4 count or viral load as a primary outcome. Most studies identified in this review were small and non-randomised, with low statistical power. Four of the 30 articles identified by this review conclude that nurse management of ART compares favourably to physician management. Seven provide evidence of the viability of managing ART at lower levels within the health system, and one indicates that vertical and integrated ART programmes can achieve similar outcomes. Five articles show that community/home-based ART management can be as effective as facility-based ART management. Five of seven articles investigating community support link it to better clinical outcomes. The results of four studies suggest that directly observed therapy may not be an important component of ART programmes. Given that the scale-up of antiretroviral therapy represents the most sweeping change in healthcare delivery in sub-Saharan Africa in recent years, it is surprising to not find more evidence from comparative studies to inform implementation strategies. The studies reported on a wide range of service delivery models, making it difficult to draw conclusions about some models. The strongest evidence was related to the feasibility of decentralisation and task-shifting, both of which appear to be effective strategies. © 2014 John Wiley & Sons Ltd.

  17. Risk factors associated with iatrogenic opioid and benzodiazepine withdrawal in critically ill pediatric patients: a systematic review and conceptual model.

    Science.gov (United States)

    Best, Kaitlin M; Boullata, Joseph I; Curley, Martha A Q

    2015-02-01

    Analgesia and sedation are common therapies in pediatric critical care, and rapid titration of these medications is associated with iatrogenic withdrawal syndrome. We performed a systematic review of the literature to identify all common and salient risk factors associated with iatrogenic withdrawal syndrome and build a conceptual model of iatrogenic withdrawal syndrome risk in critically ill pediatric patients. Multiple databases, including PubMed/Medline, EMBASE, CINAHL, and the Cochrane Central Registry of Clinical Trials, were searched using relevant terms from January 1, 1980, to August 1, 2014. Articles were included if they were published in English and discussed iatrogenic withdrawal syndrome following either opioid or benzodiazepine therapy in children in acute or intensive care settings. Articles were excluded if subjects were neonates born to opioid- or benzodiazepine-dependent mothers, children diagnosed as substance abusers, or subjects with cancer-related pain; if data about opioid or benzodiazepine treatment were not specified; or if primary data were not reported. In total, 1,395 articles were evaluated, 33 of which met the inclusion criteria. To facilitate analysis, all opioid and/or benzodiazepine doses were converted to morphine or midazolam equivalents, respectively. A table of evidence was developed for qualitative analysis of common themes, providing a framework for the construction of a conceptual model. The strongest risk factors associated with iatrogenic withdrawal syndrome include duration of therapy and cumulative dose. Additionally, evidence exists linking patient, process, and system factors in the development of iatrogenic withdrawal syndrome. Most articles were prospective observational or interventional studies. Given the state of existing evidence, well-designed prospective studies are required to better characterize iatrogenic withdrawal syndrome in critically ill pediatric patients. This review provides data to support the

  18. Large-scale movements in European badgers: has the tail of the movement kernel been underestimated?

    Science.gov (United States)

    Byrne, Andrew W; Quinn, John L; O'Keeffe, James J; Green, Stuart; Sleeman, D Paddy; Martin, S Wayne; Davenport, John

    2014-07-01

    movement distribution is currently underestimated. The implications of this for understanding the spatial ecology of badger populations and for the design of disease intervention strategies are potentially significant. © 2014 The Authors. Journal of Animal Ecology © 2014 British Ecological Society.

  19. System wide analyses have underestimated protein abundances and the importance of transcription in mammals

    Directory of Open Access Journals (Sweden)

    Jingyi Jessica Li

    2014-02-01

    Full Text Available Large scale surveys in mammalian tissue culture cells suggest that the protein expressed at the median abundance is present at 8,000–16,000 molecules per cell and that differences in mRNA expression between genes explain only 10–40% of the differences in protein levels. We find, however, that these surveys have significantly underestimated protein abundances and the relative importance of transcription. Using individual measurements for 61 housekeeping proteins to rescale whole proteome data from Schwanhausser et al. (2011, we find that the median protein detected is expressed at 170,000 molecules per cell and that our corrected protein abundance estimates show a higher correlation with mRNA abundances than do the uncorrected protein data. In addition, we estimated the impact of further errors in mRNA and protein abundances using direct experimental measurements of these errors. The resulting analysis suggests that mRNA levels explain at least 56% of the differences in protein abundance for the 4,212 genes detected by Schwanhausser et al. (2011, though because one major source of error could not be estimated the true percent contribution should be higher. We also employed a second, independent strategy to determine the contribution of mRNA levels to protein expression. We show that the variance in translation rates directly measured by ribosome profiling is only 9% of that inferred by Schwanhausser et al. (2011, and that the measured and inferred translation rates correlate poorly (R2 = 0.14. Based on this, our second strategy suggests that mRNA levels explain ∼84% of the variance in protein levels. We also determined the percent contributions of transcription, RNA degradation, translation and protein degradation to the variance in protein abundances using both of our strategies. While the magnitudes of the two estimates vary, they both suggest that transcription plays a more important role than the earlier studies implied and translation

  20. Brazilian healthcare model for people with mental disorders: a systematic literature review

    Directory of Open Access Journals (Sweden)

    Marcelo Theophilo Lima

    2013-03-01

    Full Text Available Objective: To evaluate the process of implementing the Brazilian psychiatric reform, especially regarding its impact on families’ management of healthcare issues. Methods: Interpretative research performed between August 2011 and January 2012, where symbolic interactionism was used as theoretical reference and Grounded Theory was used as the methodological reference. Initially, 49 articles on the subject were selected applying as descriptors mental health, psychiatric reform and psychosocial care, in Scielo, lIlACS and university libraries’ databases. of these, 17 articles were excluded for being published prior to 2008 and 18 for having approaches not comprised in the scope of the study. Results: The power relationships in the treatment method were identified as causal conditions of the de-hospitalization process, which occurs in a context of deficiency in the network intended to replace psychiatric hospitals, therefore requiring the participation of patients’ families in their reintegration at home and treatment. This strategy to deconstruct the psychiatric hospital-based model results in an excessive burden to the families. Conclusion: If, on one hand, the shift from hospitalization to in-home care, with embracement of the disease and of patients’ suffering in their very social relationships, was to propose the recovery of patients’ civil and human rights and their remaining into the society, on the other hand, it creates another series of problems, such as the emotional and logistical burden imposed on patients’ families.

  1. Sustainable business models: systematic approach toward successful ambulatory care pharmacy practice.

    Science.gov (United States)

    Sachdev, Gloria

    2014-08-15

    This article discusses considerations for making ambulatory care pharmacist services at least cost neutral and, ideally, generate a margin that allows for service expansion. The four pillars of business sustainability are leadership, staffing, information technology, and compensation. A key facet of leadership in ambulatory care pharmacy practice is creating and expressing a clear vision for pharmacists' services. Staffing considerations include establishing training needs, maximizing efficiencies, and minimizing costs. Information technology is essential for efficiency in patient care delivery and outcomes assessment. The three domains of compensation are cost savings, pay for performance, and revenue generation. The following eight steps for designing and implementing an ambulatory care pharmacist service are discussed: (1) prepare a needs assessment, (2) analyze existing strengths, weaknesses, opportunities, and threats, (3) analyze service gaps and feasibility, (4) consider financial opportunities, (5) consider stakeholders' interests, (6) develop a business plan, (7) implement the service, and (8) measure outcomes. Potential future changes in national healthcare policy (such as pharmacist provider status and expanded pay for performance) could enhance the opportunities for sustainable ambulatory care pharmacy practice. The key challenges facing ambulatory care pharmacists are developing sustainable business models, determining which services yield a positive return on investment, and demanding payment for value-added services. Copyright © 2014 by the American Society of Health-System Pharmacists, Inc. All rights reserved.

  2. Cone beam computed tomography and periapical lesions: a systematic review analysing studies on diagnostic efficacy by a hierarchical model.

    Science.gov (United States)

    Kruse, C; Spin-Neto, R; Wenzel, A; Kirkevang, L-L

    2015-09-01

    To evaluate using a systematic review approach the diagnostic efficacy of CBCT for periapical lesions, focusing on the evidence level of the included studies using a six-tiered hierarchical model. The MEDLINE bibliographic database was searched from 2000 to July 2013 for studies evaluating the potential of CBCT imaging in the diagnosis and planning of treatment for periapical lesions. The search strategy was limited to English language publications using the following combined terms in the search strategy: apical pathology or endodontic pathology or periapical or lesion or healing and CBCT or cone beam CT. The diagnostic efficacy level of the studies was assessed independently by four reviewers. The search identified 25 publications that qualitatively or quantitatively assessed the use of CBCT for the diagnosis of periapical lesions, in which the methodology/results comprised at least one of the following parameters: the methods, the imaging protocols or qualitative/quantitative information on how CBCT influenced the diagnosis and/or treatment plan. From the assessed studies, it can be concluded that although there is a tendency for a higher accuracy for periapical lesion detection using CBCT compared to two-dimensional imaging methods, no studies have been conducted that justify the standard use of CBCT in diagnosing periapical lesions. In addition, it should be considered that, at the present time, the efficacy of CBCT as the diagnostic imaging method for periapical lesions has been assessed merely at low diagnostic efficacy levels. © 2014 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  3. Unique and Overlapping Symptoms in Schizophrenia Spectrum and Dissociative Disorders in Relation to Models of Psychopathology: A Systematic Review

    Science.gov (United States)

    Renard, Selwyn B.; Huntjens, Rafaele J. C.; Lysaker, Paul H.; Moskowitz, Andrew; Aleman, André; Pijnenborg, Gerdina H. M.

    2017-01-01

    Schizophrenia spectrum disorders (SSDs) and dissociative disorders (DDs) are described in the fifth edition of the Diagnostic and Statistical Manual for Mental Disorders (DSM-5) and tenth edition of the International Statistical Classification of Diseases and Related Health Problems (ICD-10) as 2 categorically distinct diagnostic categories. However, several studies indicate high levels of co-occurrence between these diagnostic groups, which might be explained by overlapping symptoms. The aim of this systematic review is to provide a comprehensive overview of the research concerning overlap and differences in symptoms between schizophrenia spectrum and DDs. For this purpose the PubMed, PsycINFO, and Web of Science databases were searched for relevant literature. The literature contained a large body of evidence showing the presence of symptoms of dissociation in SSDs. Although there are quantitative differences between diagnoses, overlapping symptoms are not limited to certain domains of dissociation, nor to nonpathological forms of dissociation. In addition, dissociation seems to be related to a history of trauma in SSDs, as is also seen in DDs. There is also evidence showing that positive and negative symptoms typically associated with schizophrenia may be present in DD. Implications of these results are discussed with regard to different models of psychopathology and clinical practice. PMID:27209638

  4. Determination of counterfeit medicines by Raman spectroscopy: Systematic study based on a large set of model tablets.

    Science.gov (United States)

    Neuberger, Sabine; Neusüß, Christian

    2015-08-10

    In the last decade, counterfeit pharmaceutical products have become a widespread issue for public health. Raman spectroscopy which is easy, non-destructive and information-rich is particularly suitable as screening method for fast characterization of chemicals and pharmaceuticals. Combined with chemometric techniques, it provides a powerful tool for the analysis and determination of counterfeit medicines. Here, for the first time, a systematic study of the benefits and limitations of Raman spectroscopy for the analysis of pharmaceutical samples on a large set of model tablets, varying with respect to chemical and physical properties, was performed. To discriminate between the different mixtures, a combination of dispersive Raman spectroscopy performing in backscattering mode and principal component analysis was used. The discrimination between samples with different coatings, a varying amount of active pharmaceutical ingredients and a diversity of excipients were possible. However, it was not possible to distinguish between variations of the press power, mixing quality and granulation. As a showcase, the change in Raman signals of commercial acetylsalicylic acid effervescent tablets due to five different storage conditions was monitored. It was possible to detect early small chemical changes caused by inappropriate storage conditions. These results demonstrate that Raman spectroscopy combined with multivariate data analysis provides a powerful methodology for the fast and easy characterization of genuine and counterfeit medicines. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. Systematic in vitro nanotoxicity study on anodic alumina nanotubes with engineered aspect ratio: understanding nanotoxicity by a nanomaterial model.

    Science.gov (United States)

    Wang, Ye; Kaur, Gagandeep; Zysk, Aneta; Liapis, Vasilios; Hay, Shelley; Santos, Abel; Losic, Dusan; Evdokiou, Andreas

    2015-04-01

    Here, we report a detailed and systematic approach for studying the in vitro nanotoxicity study of high aspect ratio (HAR) nanomaterials using anodic alumina nanotubes (AANTs) as a nanomaterial model. AANTs with bio-inert properties and tailored aspect ratios ranging from 7.8 to 63.3 were synthesized by an electrochemical pulse anodization process. Cytotoxicity studies were conducted with RAW 264.7 mouse macrophage cells and MDA-MB 231-TXSA human breast cancer cells through several toxicity parameters, including cell viability and morphology, pro-inflammatory response, mitochondrial depolarization, lysosomal membrane permeabilization (LMP), induction of autophagy and endoplasmic reticulum (ER) stress. The resulting toxicity patterns were cell-type dependent and strongly related with AANTs dose, length of time, and importantly the AR of AANTs. Long AANTs triggered enhanced cell death, morphological changes, tumor necrosis factor α (TNF-α) release, LMP and ER stress than short AANTs. The toxic AR window of AANTs was determined to be 7.8, which is shorter than that of other previously reported HAR nanomaterials. This toxic AR window provides a promising opportunity to control the nanotoxicity of HAR nanomaterials for their advanced drug delivery application. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Systematic Identification of Machine-Learning Models Aimed to Classify Critical Residues for Protein Function from Protein Structure.

    Science.gov (United States)

    Corral-Corral, Ricardo; Beltrán, Jesús A; Brizuela, Carlos A; Del Rio, Gabriel

    2017-10-09

    Protein structure and protein function should be related, yet the nature of this relationship remains unsolved. Mapping the critical residues for protein function with protein structure features represents an opportunity to explore this relationship, yet two important limitations have precluded a proper analysis of the structure-function relationship of proteins: (i) the lack of a formal definition of what critical residues are and (ii) the lack of a systematic evaluation of methods and protein structure features. To address this problem, here we introduce an index to quantify the protein-function criticality of a residue based on experimental data and a strategy aimed to optimize both, descriptors of protein structure (physicochemical and centrality descriptors) and machine learning algorithms, to minimize the error in the classification of critical residues. We observed that both physicochemical and centrality descriptors of residues effectively relate protein structure and protein function, and that physicochemical descriptors better describe critical residues. We also show that critical residues are better classified when residue criticality is considered as a binary attribute (i.e., residues are considered critical or not critical). Using this binary annotation for critical residues 8 models rendered accurate and non-overlapping classification of critical residues, confirming the multi-factorial character of the structure-function relationship of proteins.

  7. From lime to silica and alumina: systematic modeling of cement clinkers using a general force-field.

    Science.gov (United States)

    Freitas, A A; Santos, R L; Colaço, R; Bayão Horta, R; Canongia Lopes, J N

    2015-07-28

    Thirteen different cement-clinker crystalline phases present in the lime-silica-alumina system have been systematically modeled using a simple and general force field. This constitutes a new type of approach towards the study of lime-silica-alumina systems, where the simpler and more transferable Lennard-Jones potential was used instead of the more traditional Buckingham potential. The results were validated using experimental density and structural data. The elastic properties were also considered. Six amorphous phases (corresponding to calcium/silicon ratios corresponding to belite, rankinite, wollastonite and alumina-doped amorphous wollastonite with 5%, 10% and 15% alumina content) were also studied using molecular dynamics simulations. The obtained MD trajectories were used to characterize the different crystalline and amorphous phases in terms of the corresponding radial distribution functions, aggregate analyses and connectivity among silica groups. These studies allowed a direct comparison between the crystalline and amorphous phases and revealed how the structure of the silica network was modified in the amorphous materials or by the inclusion of other structural units such as alumina. The knowledge at an atomistic level of such modifications is paramount for the formulation of new cement-clinker phases.

  8. A Solvent-Mediated Coarse-Grained Model of DNA Derived with the Systematic Newton Inversion Method.

    Science.gov (United States)

    Naômé, Aymeric; Laaksonen, Aatto; Vercauteren, Daniel P

    2014-08-12

    We present a new class of coarse-grained (CG) force fields (FFs) for B-DNA with explicit ions suited for large-scale mesoscale simulations at microsecond-micrometer scale using a wide spectrum of particle simulation methods from molecular dynamics to dissipative particle dynamics. The effective solvent-mediated pairwise interactions making up the FFs are obtained by inverting radial distribution functions and other particle-particle distributions obtained from all-atom simulations of numbers of octadecamer DNA fragments from the Ascona B-DNA library. The inverse Monte Carlo (IMC) method, later known as Newton inversion (NI) (Lyubartsev, A. P.; Laaksonen, A. Phys. Rev. E, 1995, 52, 3730-3737), was used together with the iterative Boltzmann inversion (IBI) scheme to compute the effective CG potentials. We show that this systematic structure-based approach is capable of providing converged potentials that accurately reproduce the structural features of the underlying atomistic system within a few percents of relative difference. We also show that a simple one-site-per-nucleotide model with 10 intramolecular pair interaction potentials is able to reproduce key features of DNA, for example, the persistence length and its dependence on the ionic concentration, experimentally determined around 50 nm at physiological salt concentration.

  9. A Systematic Review of Perennial Staple Crops Literature Using Topic Modeling and Bibliometric Analysis.

    Science.gov (United States)

    Kane, Daniel A; Rogé, Paul; Snapp, Sieglinde S

    2016-01-01

    Research on perennial staple crops has increased in the past ten years due to their potential to improve ecosystem services in agricultural systems. However, multiple past breeding efforts as well as research on traditional ratoon systems mean there is already a broad body of literature on perennial crops. In this review, we compare the development of research on perennial staple crops, including wheat, rice, rye, sorghum, and pigeon pea. We utilized the advanced search capabilities of Web of Science, Scopus, ScienceDirect, and Agricola to gather a library of 914 articles published from 1930 to the present. We analyzed the metadata in the entire library and in collections of literature on each crop to understand trends in research and publishing. In addition, we applied topic modeling to the article abstracts, a type of text analysis that identifies frequently co-occurring terms and latent topics. We found: 1.) Research on perennials is increasing overall, but individual crops have each seen periods of heightened interest and research activity; 2.) Specialist journals play an important role in supporting early research efforts. Research often begins within communities of specialists or breeders for the individual crop before transitioning to a more general scientific audience; 3.) Existing perennial agricultural systems and their domesticated crop material, such as ratoon rice systems, can provide a useful foundation for breeding efforts, accelerating the development of truly perennial crops and farming systems; 4.) Primary research is lacking for crops that are produced on a smaller scale globally, such as pigeon pea and sorghum, and on the ecosystem service benefits of perennial agricultural systems.

  10. Systematic study of multi-quasiparticle K -isomeric bands in tungsten isotopes by the extended projected shell model

    Science.gov (United States)

    Wu, Xin-Yi; Ghorui, S. K.; Wang, Long-Jun; Sun, Yang; Guidry, Mike; Walker, Philip M.

    2017-06-01

    Background: The interplay between collective and single-particle degrees of freedom is an important structure aspect to study. The nuclei in the A ≈180 mass region are often denoted as good examples to study such problems because these nuclei are known to exhibit many rotational bands based on multi-quasiparticle K isomers. Purpose: A large set of high-quality experimental data on high-K isomeric states in the A ≈180 mass region has accumulated. A systematic description of them is a theoretical challenge as it requires a method going beyond the usual mean field with multi-quasiparticle configurations built in the shell-model basis. The K -isomer data provide an ideal testing ground for theoretical models. Method: The recently extended projected shell model (PSM) by the Pfaffian method is employed with a sufficiently large configuration space including up to 10 quasiparticles. The restoration of rotational symmetry which is broken in the deformed mean field is obtained by means of angular-momentum projection. With axial symmetry in the basis deformation, each multi-quasiparticle state, classified by a K quantum number, represents the major component of a rotational K band. Shell-model diagonalization in such a projected basis defines the K mixing, which is the key ingredient of the present method. Results: Quasiparticle structure and rotational properties of high-K isomers in even-even neutron-rich W-186174 isotopes are described. The rotational evolution of the yrast and near-yrast bands is discussed with successive band crossings. Multi-quasiparticle K isomers and associated rotational bands in each W isotope are studied with detailed quasiparticle configurations given. Electromagnetic transition properties are also studied and the calculated B (E 2 ),B (M 1 ) , and g -factors are compared with experiment if data exist. Conclusions: Many nuclei of the A ≈180 mass region exhibit properties of an axially symmetric shape and K is approximately a good quantum

  11. Impact of a quasi-stochastic cellular automaton backscatter scheme on the systematic error and seasonal prediction skill of a global climate model.

    Science.gov (United States)

    Berner, J; Doblas-Reyes, F J; Palmer, T N; Shutts, G; Weisheimer, A

    2008-07-28

    The impact of a nonlinear dynamic cellular automaton (CA) model, as a representation of the partially stochastic aspects of unresolved scales in global climate models, is studied in the European Centre for Medium Range Weather Forecasts coupled ocean-atmosphere model. Two separate aspects are discussed: impact on the systematic error of the model, and impact on the skill of seasonal forecasts. Significant reductions of systematic error are found both in the tropics and in the extratropics. Such reductions can be understood in terms of the inherently nonlinear nature of climate, in particular how energy injected by the CA at the near-grid scale can backscatter nonlinearly to larger scales. In addition, significant improvements in the probabilistic skill of seasonal forecasts are found in terms of a number of different variables such as temperature, precipitation and sea-level pressure. Such increases in skill can be understood both in terms of the reduction of systematic error as mentioned above, and in terms of the impact on ensemble spread of the CA's representation of inherent model uncertainty.

  12. A systematic review of primary care models for non-communicable disease interventions in Sub-Saharan Africa.

    Science.gov (United States)

    Kane, Jennifer; Landes, Megan; Carroll, Christopher; Nolen, Amy; Sodhi, Sumeet

    2017-03-23

    Chronic diseases, primarily cardiovascular disease, respiratory disease, diabetes and cancer, are the leading cause of death and disability worldwide. In sub-Saharan Africa (SSA), where communicable disease prevalence still outweighs that of non-communicable disease (NCDs), rates of NCDs are rapidly rising and evidence for primary healthcare approaches for these emerging NCDs is needed. A systematic review and evidence synthesis of primary care approaches for chronic disease in SSA. Quantitative and qualitative primary research studies were included that focused on priority NCDs interventions. The method used was best-fit framework synthesis. Three conceptual models of care for NCDs in low- and middle-income countries were identified and used to develop an a priori framework for the synthesis. The literature search for relevant primary research studies generated 3759 unique citations of which 12 satisfied the inclusion criteria. Eleven studies were quantitative and one used mixed methods. Three higher-level themes of screening, prevention and management of disease were derived. This synthesis permitted the development of a new evidence-based conceptual model of care for priority NCDs in SSA. For this review there was a near-consensus that passive rather than active case-finding approaches are suitable in resource-poor settings. Modifying risk factors among existing patients through advice on diet and lifestyle was a common element of healthcare approaches. The priorities for disease management in primary care were identified as: availability of essential diagnostic tools and medications at local primary healthcare clinics and the use of standardized protocols for diagnosis, treatment, monitoring and referral to specialist care.

  13. The potential of social enterprise to enhance health and well-being: a model and systematic review.

    Science.gov (United States)

    Roy, Michael J; Donaldson, Cam; Baker, Rachel; Kerr, Susan

    2014-12-01

    In recent years civil society organisations, associations, institutions and groups have become increasingly involved at various levels in the governance of healthcare systems around the world. In the UK, particularly in the context of recent reform of the National Health Service in England, social enterprise - that part of the third sector engaged in trading - has come to the fore as a potential model of state-sponsored healthcare delivery. However, to date, there has been no review of evidence on the outcomes of social enterprise involvement in healthcare, nor in the ability of social enterprise to address health inequalities more widely through action on the social determinants of health. Following the development of an initial conceptual model, this systematic review identifies and synthesises evidence from published empirical research on the impact of social enterprise activity on health outcomes and their social determinants. Ten health and social science databases were searched with no date delimiters set. Inclusion and exclusion criteria were applied prior to data extraction and quality appraisal. Heterogeneity in the outcomes assessed precluded meta-analysis/meta-synthesis and so the results are therefore presented in narrative form. Five studies met the inclusion criteria. The included studies provide limited evidence that social enterprise activity can impact positively on mental health, self-reliance/esteem and health behaviours, reduce stigmatization and build social capital, all of which can contribute to overall health and well-being. No empirical research was identified that examined social enterprise as an alternative mode of healthcare delivery. Due to the limited evidence available, we discuss the relationship between the evidence found and other literature not included in the review. There is a clear need for research to better understand and evidence causal mechanisms and to explore the impact of social enterprise activity, and wider civil

  14. Endogenous implementation of technology gap in energy optimization models-a systematic analysis within TIMES G5 model

    International Nuclear Information System (INIS)

    Rout, Ullash K.; Fahl, Ulrich; Remme, Uwe; Blesl, Markus; Voss, Alfred

    2009-01-01

    Evaluation of global diffusion potential of learning technologies and their timely specific cost development across regions is always a challenging issue for the future technology policy preparation. Further the process of evaluation gains interest especially by endogenous treatment of energy technologies under uncertainty in learning rates with technology gap across the regions in global regional cluster learning approach. This work devised, implemented, and examined new methodologies on technology gaps (a practical problem), using two broad concepts of knowledge deficit and time lag approaches in global learning, applying the floor cost approach methodology. The study was executed in a multi-regional, technology-rich and long horizon bottom-up linear energy system model on The Integrated MARKAL EFOM System (TIMES) framework. Global learning selects highest learning technologies in maximum uncertainty of learning rate scenario, whereas any form of technology gap retards the global learning process and discourages the technologies deployment. Time lag notions of technology gaps prefer heavy utilization of learning technologies in developed economies for early reduction of specific cost. Technology gaps of any kind should be reduced among economies through the promotion and enactment of various policies by governments, in order to utilize the technological resources by mass deployment to combat ongoing climate change.

  15. Forecasting the mortality rates using Lee-Carter model and Heligman-Pollard model

    Science.gov (United States)

    Ibrahim, R. I.; Ngataman, N.; Abrisam, W. N. A. Wan Mohd

    2017-09-01

    Improvement in life expectancies has driven further declines in mortality. The sustained reduction in mortality rates and its systematic underestimation has been attracting the significant interest of researchers in recent years because of its potential impact on population size and structure, social security systems, and (from an actuarial perspective) the life insurance and pensions industry worldwide. Among all forecasting methods, the Lee-Carter model has been widely accepted by the actuarial community and Heligman-Pollard model has been widely used by researchers in modelling and forecasting future mortality. Therefore, this paper only focuses on Lee-Carter