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1.
Water Sci Technol ; 80(3): 517-528, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31596263

RESUMO

Selecting a proper spatial resolution for urban rainfall runoff modeling was not a trivial issue because it could affect the model outputs. Recently, the development of remote sensing technology and increasingly available data source had enabled rainfall runoff process to be modeled at detailed and microscales. However, the models with less complexity might have equally good performance with less model establishment and computation time. This study attempted to explore the impact of model spatial resolution on model performance and parameters. Models with different discretization degree were built up on the basis of actual drainage networks, urban parcels and specific land use. The results showed that there was very little difference in the total runoff volumes while peak flows showed obvious scale effects which could be up to 30%. Generally, model calibration could compensate the scale effect. The calibrated models with different resolution showed similar performances. The consideration of effective impervious area (EIA) as a calibration parameter marginally increased performance of the calibration period but also slightly decreased performance in the validation period which indicated the importance of detailed EIA identification.


Assuntos
Hidrologia , Tecnologia de Sensoriamento Remoto , Calibragem , Modelos Teóricos , Chuva , Movimentos da Água
2.
Bratisl Lek Listy ; 120(9): 650-657, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31475548

RESUMO

In this contribution we present graph theoretical approach to image processing focus on biological data. We use the graph cut algorithms and extend them for obtaining segmentation of biological data. We deal with tumor brain cells and rats brain to show the existence and presence of inflammatory molecules. We introduce a completely new method for filtering of data (Tab. 3, Schema 4, Fig. 7, Ref. 13). Keywords: graph cuts, segmentation, tumore analyses of cells, computer morphometry.


Assuntos
Algoritmos , Neoplasias Encefálicas/patologia , Processamento de Imagem Assistida por Computador , Modelos Teóricos , Animais , Encéfalo/citologia , Ratos
3.
Water Sci Technol ; 80(2): 290-299, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31537765

RESUMO

One of the most common strategies for sewer cleaning is to generate flushing flows using flushing gates to store water in the upstream sewer pipe. Therefore it is important to obtain the flow information on the flushing waves and their eroding effects. In this study, the flow characteristics of the flushing wave and the flushing effect were investigated by a transient flow calculation using a commercial computational fluid dynamics (CFD) code. The values of bottom shear stress were obtained and the effect of several factors are discussed. The water depth and the slope were related to the release rate of the storage volume, while the flushing volume determined the flushing distance at long sewer distances. The initial downstream water level was found to dramatically reduce the flushing effect. Equations based on the storage depth were developed to estimate the flushing effect, and suggestions for the installation and operation of flushing gates are provided.


Assuntos
Eliminação de Resíduos Líquidos , Movimentos da Água , Modelos Teóricos , Esgotos , Estresse Mecânico
4.
Water Sci Technol ; 80(2): 339-346, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31537770

RESUMO

In this work, the integration of dynamic bioenergetic calculations in the IWA Anaerobic Digestion Model No. 1 (ADM1) is presented. The impact of bioenergetics on kinetics was addressed via two different approaches: a thermodynamic-based inhibition function and variable microbial growth yields based on dynamic Gibbs free energy calculations. The dynamic bioenergetic calculations indicate that the standard ADM1 predicts positive reaction rates under thermodynamically unfeasible conditions. The dissolved hydrogen inhibition approach used in ADM1 is, however, deemed as adequate, offering the trade-off of not requiring dynamic bioenergetics computation despite the need of hydrogen inhibition parameters. Simulations of the model with bioenergetics showed the low amount of energy available in butyrate and propionate oxidation, suggesting that microbial growth on these substrates must be very limited or occur via alternative mechanisms rather than dissolved hydrogen.


Assuntos
Anaerobiose , Modelos Teóricos , Reatores Biológicos , Hidrogênio , Cinética , Termodinâmica
5.
Rev Med Suisse ; 15(663): 1661-1665, 2019 Sep 18.
Artigo em Francês | MEDLINE | ID: mdl-31532117

RESUMO

Substance use in adolescence can have a negative impact in the short and long terms. Fighting the deleterious effects of substance abuse is a public health issue. All adults who supervise adolescents, both specialized and not specialized professionals, can be involved in preventive actions. Young people at risk must be identified early enough and referred to appropriate care. It is therefore crucial that first-line professionals should be able to detect nascent problems and to understand signs of appeal. Professionals must be willing to raise drug consumption topics in their interviews and, thereafter, seek advice and guidance from specialized organizations. One such organization is DEPART which offers an intervention model for adolescents and their families as well as for professionals by offering them support and training.


Assuntos
Saúde Pública , Transtornos Relacionados ao Uso de Substâncias , Humanos , Modelos Teóricos , Saúde Pública/métodos , Saúde Pública/tendências , Fatores de Risco , Transtornos Relacionados ao Uso de Substâncias/prevenção & controle , Transtornos Relacionados ao Uso de Substâncias/terapia
6.
Ying Yong Sheng Tai Xue Bao ; 30(7): 2309-2319, 2019 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-31418234

RESUMO

We estimated grassland NPP using CASA model in the Loess Plateau during 2000-2015 and further analyzed the spatiotemporal dynamics, stability and persistence of grassland NPP. The driving factors of grassland NPP were analyzed from four aspects, i.e., vegetation types, topographic factors, climate change, and human activities. The results showed that the average NPP was 202.93 g C·m-2·a-1. The grassland NPP showed an increasing trend with an average increase rate of 2.43 g C·m-2·a-1. The distribution of NPP in grassland had obvious spatial heterogeneity, which was generally high in the south and low in the north. 91.2% of the total grassland area showed an increasing trend, mainly distributed in most areas of Shaanxi Province, Longdong and Longzhong areas of Gansu Province, and most parts of Qinghai Province. The regions with a stable growth condition of grassland NPP mainly located in the south of Ordos, northern Shaanxi, and Gansu. The future change trend of grassland NPP would be consistent with that of the past in most areas. The grassland NPP would continue to increase in most areas of Shaanxi Province, Longzhong and Longdong areas in Gansu Province. The average NPP of slope grassland was 703.37 g C·m-2·a-1, while that of alpine and subalpine grassland was 57.28 g C·m-2·a-1. The grassland NPP was higher in high altitude area and relative low in plain and hilly area. The increased precipitation promoted the increase of grassland NPP during the study period. Human activities such as improvement of overgrazing and returning cropland to grassland also played an important role in the increase of grassland NPP in the Loess Plateau.


Assuntos
Pradaria , Modelos Teóricos , China , Mudança Climática , Atividades Humanas
7.
Ying Yong Sheng Tai Xue Bao ; 30(7): 2329-2337, 2019 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-31418236

RESUMO

Maxent niche model was used to project the potential distribution of alien plant species Spartina alterniflora in China, with 96 S. alterniflora records and marine and climatic data along China coastal area. The results showed that suitable area for the distribution of S. alterniflora occupied 85% of coastal areas, with the highly suitable area, the medium, and low suitable area accounting for 18%, 34% and 33%, respectively. Only 15% of the coastal areas were regions with distribution possibility of less than 5%. Its distribution suitability was mainly related to annual lowest seawater temperature, annual mean seawater temperature, annual mean air temperature, and annual lowest temperature in January. However, the importance of annual mean precipitation, annual mean daily diurnal range, seawater salinity, annual highest seawater temperature, annual highest tempe-rature in June and current velocity was relatively small. At the highly suitable areas for S. alterni-flora, the annual lowest seawater temperature ranged from 0.62 to 24.81 ℃, the annual mean seawater temperature ranged from 10.46 to 27.29 ℃, the annual mean air temperature was between 9 to 25 ℃, and the annual lowest temperature in January was between -13.5 and 16.7 ℃. The distribution possibility of S. alterniflora in the northern coastal area was over 20%, indicating it has a great potential to invade further north in China, especially in Bohai Bay areas. According to the current distribution records and climatic data in China, the invasion risk of S. alterniflora in central and southern coasts of Hainan and most regions of Taiwan Province was low, but the possibility of future invasion can not be excluded.


Assuntos
Espécies Introduzidas , Modelos Teóricos , Áreas Alagadas , China , Poaceae , Taiwan
8.
J Chem Phys ; 151(7): 074903, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31438701

RESUMO

Ionic microgels are soft colloidal particles, composed of crosslinked polymer networks, which ionize and swell when dispersed in a good solvent. Swelling of these permeable, compressible particles involves a balance of electrostatic, elastic, and mixing contributions to the single-particle osmotic pressure. The electrostatic contribution depends on the distributions of mobile counterions and coions and of fixed charge on the polymers. Within the cell model, we employ two complementary methods to derive the electrostatic osmotic pressure of ionic microgels. In Poisson-Boltzmann (PB) theory, we minimize a free energy functional with respect to the electrostatic potential to obtain the bulk pressure. From the pressure tensor, we extract the electrostatic and gel contributions to the total pressure. In a statistical mechanical approach, we vary the free energy with respect to microgel size to obtain exact relations for the microgel electrostatic osmotic pressure. We present results for planar, cylindrical, and spherical geometries. For models of membranes and microgels with fixed charge uniformly distributed over their surface or volume, we derive analogs of the contact value theorem for charged colloids. We validate these relations by solving the PB equation and computing ion densities and osmotic pressures. When implemented within PB theory, the two methods yield identical electrostatic osmotic pressures for surface-charged microgels. For volume-charged microgels, the exact electrostatic osmotic pressure equals the average of the corresponding PB profile over the gel volume. We demonstrate that swelling of ionic microgels depends on the variation of the electrostatic pressure inside the particle and discuss implications for interpreting experiments.


Assuntos
Modelos Teóricos , Pressão Osmótica , Géis , Permeabilidade , Eletricidade Estática , Termodinâmica
9.
Top Curr Chem (Cham) ; 377(5): 22, 2019 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-31444578

RESUMO

A methodology for photocatalytic reactor modeling applied to advanced oxidation processes for chemical pollution abatement is presented herein. Three distinct reactor configurations typically employed in the field of air and water purification-wall reactors, slurry reactors, and fixed-bed reactors-are considered to illustrate the suggested approach. Initially, different mechanistically derived kinetic expressions to represent the photocatalytic rate of pollutant degradation are reviewed, indicating the main assumptions made by the authors in the published contributions. These kinetic expressions are needed to solve the mass balances of the reactant species in the photocatalytic reactors. As is well known, at least one of the steps of the reaction mechanism requires evaluation of the rate of electron-hole generation, which depends on the photon absorption rate: a volumetric property for reactions with the catalyst particles in aqueous suspension or a surface property for systems with a fixed catalyst deposited on an inert support. Subsequently, the different techniques for evaluating the optical properties of slurry and immobilized systems, and the numerical methods applied to calculate the photon absorption rate, are described. The experimental and theoretical results of pollutant degradation in each reactor type are then presented and analyzed. Finally, the definition, calculation, and relevance of different efficiency parameters are briefly reviewed. Using these illustrative examples, we emphasize the need for a systematic and rigorous approach for photocatalytic reactor modeling in order to overcome the inherent drawbacks of photocatalysis and to improve the overall efficiency of the process.


Assuntos
Luz , Modelos Teóricos , Poluentes Químicos da Água/química , Catálise , Ácido Clofíbrico/química , Cinética , Oxirredução , Fótons , Titânio/química
10.
Ying Yong Sheng Tai Xue Bao ; 30(8): 2783-2792, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31418204

RESUMO

In the past decade, the number of islands fixed link with mainland has been increasing rapidly. The construction of such projects improves the accessibility of islands, which results in a rapid increase of tourists and economic income. However, the rapid change of land use and increases of tourists will make the islands more vulnerable. It is urgent to formulate ecosystem management strategy for island ecosystems based on the scientifical prediction of the island ecological vulnerability and accurate identification of sensitive areas. Island ecological vulnerability assessment model was used to evaluate the ecological vulnerability of Zhujiajian Island. Taking 2015 as the starting date, we simulated the changes of tourists and land use, as well as the changes of island ecological vulnerability in the next 20 years. Then, the management strategy was formulated based on the vulnerability assessment and sensitive analysis. The results showed that the ecosystem of Zhujiajian Island was in good condition now, with limited area at moderate and severe vulnerable status. With the rapid increases of tourists and island development intensity, the ecological vulnerability of the island tended to more vulnerability with the increases of severe vulnerability and shrink of low vulnerability. According to the vulnerability assessment and sensitivity analysis, the Zhujiajian Island could be divided into prohibited development zones, restricted development zones and conditional development zones with different ecosystem management strategies.


Assuntos
Ecologia , Ecossistema , China , Conservação dos Recursos Naturais , Ilhas , Modelos Teóricos
11.
Soft Matter ; 15(33): 6630-6641, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31403143

RESUMO

The mechanics of blister delamination and growth plays a major role in a diversity of areas including medicine (skin pathology and mechanics of cell membranes), materials (adhesive and fracture) or soft robotics (actuation and morphing). The behavior of a blister in this context is typically difficult to grasp as it arises from the interplay of two highly nonlinear and time-dependent processes: membrane attachment and decohesion from a substrate. In the present work, we device a simplified approach, based on experimental systems, to predict the deformation path of a blister under various conditions. For this, we consider the problem of a growing blister made of a rubber-like membrane adhered on a rigid substrate, and develop a theoretical and experimental framework to study its stability and growth. We start by constructing a theoretical model of viscoelastic blister growth which we later validate with an experimental setup. We show that blister growth is controlled by the competition between two instabilities: one inherent to the rubber, and a second one pertaining to the adhesion with the substrate. Using these concepts, we show that a "targeted" stable blister shape can be achieved by controlling two parameters: the thickness of the film and the inflation rate.


Assuntos
Simulação por Computador , Membranas Artificiais , Modelos Teóricos , Adsorção , Elasticidade , Cinética , Propriedades de Superfície , Termodinâmica , Viscosidade
12.
Water Sci Technol ; 79(12): 2260-2270, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31411580

RESUMO

When manually calibrating water quality models, considerable time and attention are required. Hence, developing an automated model that allows for efficient and objective automatic calibration is highly desirable. The QUAL2Kw model calibrates the QUAL2K automatically using a genetic algorithm (GA). This study analyzes auto-calibration results and selects the optimal criterion for each objective function from six performance criteria. Additionally, a multi-objective auto-calibration was conducted using two kinds of performance statistics as the objective function of the GA. The auto-calibration model was applied to the Yeongsan River and the total maximum daily load (TMDL) was established to achieve water quality goals at specific target points of this river. Among the six auto-calibration results based on a single performance criterion, Nash-Sutcliffe model efficiency (NSE) was the best criterion for calculating fitness through auto-calibration. To consider the calibration accuracies of the TMDL target points and the entire river simultaneously, an objective function using multiple performance criteria, specifically the weighted average of the normalized root mean squares error (CV(RMSE)) and the ratio of the RMSE to the standard deviation of the observed data (the RSR), was selected as the final auto-calibration of the model. The model calibration performance was good across the whole region as well as at the target points.


Assuntos
Monitoramento Ambiental , Rios , Calibragem , Modelos Teóricos , Movimentos da Água , Qualidade da Água
13.
Stud Health Technol Inform ; 264: 1831-1832, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31438365

RESUMO

Observational research in cancer requires substantially more detail than most other therapeutic areas. Cancer conditions are defined through histology, affected anatomical structures, staging and grading, and biomarkers, and are treated with complex therapies. Here, we show a new cancer module as part of the OMOP CDM, allowing manual and automated abstraction and standardized analytics. We tested the model in EHR and registry data against a number of typical use cases.


Assuntos
Registros Eletrônicos de Saúde , Modelos Teóricos , Neoplasias , Pesquisa , Bases de Dados Factuais , Sistema de Registros
14.
Stud Health Technol Inform ; 264: 1843-1844, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31438371

RESUMO

A common data model for clinical NGS panel data that is used in a distributed research network to achieve large scale to make evidence for improving patient care should be developed. This study developed OMOP-CDM extension for NGS panel data and confirmed the feasibility of the model by finding the differences between a database generated by research-purpose and clinical practice. We believe this data model can be used in distributed research model and will facilitate the usage of the clinical NGS data in patient care.


Assuntos
Bases de Dados Factuais , Genômica , Modelos Teóricos , Humanos
15.
Stud Health Technol Inform ; 263: 1-8, 2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-31411148

RESUMO

This chapter introduces the idea of theories in health informatics, defines what we mean by theory and distinguishes theories from models, frameworks and predictive principles. After explaining why theories and predictive principles are needed to help us professionalize our discipline, the chapter offers five criteria for a successful predictive principle, discusses how to evaluate predictive principles and theories and links this with the emerging field of evidence-based health informatics. The chapter concludes with three actions needed to move the discipline of theory-based health informatics forward.


Assuntos
Informática Médica , Modelos Teóricos
16.
Stud Health Technol Inform ; 263: 87-97, 2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-31411155

RESUMO

This chapter introduces Actor-Network Theory, a sociotechnical approach to studying health information technology implementation. The chapter is intended as a pragmatic introduction to the field, acknowledging that there are many contested features of an Actor-Network Theory informed methodology. Nevertheless, the approach can be usefully drawn on to help to focus data collection and sampling. A case study describing the application of Actor-Network Theory to study the "failed" implementation of national electronic health records in England as part of a national "top-down" implementation program illustrates the main tenets of the approach and provides concrete examples of how Actor-Network Theory may be applied. In doing so, this chapter offers a reflexive account of how Actor-Network Theory has provided a nuanced analysis of how the implementation of national electronic health records affected different stakeholders, organizations and technology.


Assuntos
Registros Eletrônicos de Saúde , Informática Médica , Inglaterra , Modelos Teóricos
17.
Stud Health Technol Inform ; 263: 205-218, 2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-31411164

RESUMO

In this chapter, we reflect on the aim and objectives of the textbook and address known gaps in our theory coverage. We reinforce the importance of theory in health informatics and review the varying disciplinary origins of the theories considered in the book. We discuss the question of what makes a good theory and how to know which one is relevant for a given study. We recognize the limitations of the body of theory that we have presented and suggest what might be regarded as "native" theory that is original to health informatics. Finally, we propose topics to form a research agenda for theory in health informatics.


Assuntos
Informática Médica , Modelos Teóricos , Pesquisa/tendências
18.
BMC Bioinformatics ; 20(1): 409, 2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-31362694

RESUMO

BACKGROUND: Internal ribosome entry sites (IRES) are segments of mRNA found in untranslated regions that can recruit the ribosome and initiate translation independently of the 5' cap-dependent translation initiation mechanism. IRES usually function when 5' cap-dependent translation initiation has been blocked or repressed. They have been widely found to play important roles in viral infections and cellular processes. However, a limited number of confirmed IRES have been reported due to the requirement for highly labor intensive, slow, and low efficiency laboratory experiments. Bioinformatics tools have been developed, but there is no reliable online tool. RESULTS: This paper systematically examines the features that can distinguish IRES from non-IRES sequences. Sequence features such as kmer words, structural features such as QMFE, and sequence/structure hybrid features are evaluated as possible discriminators. They are incorporated into an IRES classifier based on XGBoost. The XGBoost model performs better than previous classifiers, with higher accuracy and much shorter computational time. The number of features in the model has been greatly reduced, compared to previous predictors, by including global kmer and structural features. The contributions of model features are well explained by LIME and SHapley Additive exPlanations. The trained XGBoost model has been implemented as a bioinformatics tool for IRES prediction, IRESpy (https://irespy.shinyapps.io/IRESpy/), which has been applied to scan the human 5' UTR and find novel IRES segments. CONCLUSIONS: IRESpy is a fast, reliable, high-throughput IRES online prediction tool. It provides a publicly available tool for all IRES researchers, and can be used in other genomics applications such as gene annotation and analysis of differential gene expression.


Assuntos
Biologia Computacional/métodos , Sítios Internos de Entrada Ribossomal/genética , Software , Regiões 5' não Traduzidas/genética , Algoritmos , Sequência de Bases , Humanos , Modelos Teóricos , Probabilidade , RNA Viral/genética
19.
BMC Bioinformatics ; 20(1): 419, 2019 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-31409275

RESUMO

BACKGROUND: Alignment of sequence families described by profiles provides a sensitive means for establishing homology between proteins and is important in protein evolutionary, structural, and functional studies. In the context of a steadily growing amount of sequence data, estimating the statistical significance of alignments, including profile-profile alignments, plays a key role in alignment-based homology search algorithms. Still, it is an open question as to what and whether one type of distribution governs profile-profile alignment score, especially when profile-profile substitution scores involve such terms as secondary structure predictions. RESULTS: This study presents a methodology for estimating the statistical significance of this type of alignments. The methodology rests on a new algorithm developed for generating random profiles such that their alignment scores are distributed similarly to those obtained for real unrelated profiles. We show that improvements in statistical accuracy and sensitivity and high-quality alignment rate result from statistically characterizing alignments by establishing the dependence of statistical parameters on various measures associated with both individual and pairwise profile characteristics. Implemented in the COMER software, the proposed methodology yielded an increase of up to 34.2% in the number of true positives and up to 61.8% in the number of high-quality alignments with respect to the previous version of the COMER method. CONCLUSIONS: The more accurate estimation of statistical significance is implemented in the COMER method, which is now more sensitive and provides an increased rate of high-quality profile-profile alignments. The results of the present study also suggest directions for future research.


Assuntos
Modelos Teóricos , Proteínas/química , Algoritmos , Sequência de Aminoácidos , Conformação Proteica , Alinhamento de Sequência
20.
J Environ Manage ; 248: 109052, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31466185

RESUMO

It is crucial to be able to forecast flows and overflows in urban drainage systems to build good and effective real-time control and warning systems. Due to computational constraints, it may often be unfeasible to employ detailed 1D hydrodynamic models for real-time purposes, and surrogate models can be used instead. In rural hydrology, forecast models are usually built or calibrated using long historical time series of, for example, flow or level observations, but such series are typically not available for the ever-changing urban drainage systems. In the current study, we therefore used a fast, reservoir-based surrogate forecast model constructed from a 1D hydrodynamic urban drainage model. Thus, we did not rely directly on historical time series data. Forecast models should preferably be able to update their internal states based on observations to ensure the best initial conditions for each forecast. We therefore used the Ensemble Kalman filter to update the surrogate model before each forecast. Water level or flow observations were assimilated into the model either directly, or indirectly using rating curves. The model forecasts were validated against observed flows and overflows. The results showed that model updating improved the forecasts up to 2 h ahead, but also that updating using water level observations resulted in better flow forecasts than assimilation based on flow data. Furthermore, updating with water level observations was insensitive to changes in the noise formulation used for the Ensemble Kalman filter, meaning that the method is suitable for operational settings where there is often little time and data for fine-tuning.


Assuntos
Hidrologia , Modelos Teóricos , Previsões
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