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1.
Chaos ; 34(2)2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38377296

RESUMO

While quite a few recent papers have explored game-resource feedback using the framework of evolutionary game theory, almost all the studies are confined to using time-continuous dynamical equations. Moreover, in such literature, the effect of ubiquitous chaos in the resulting eco-evolutionary dynamics is rather missing. Here, we present a deterministic eco-evolutionary discrete-time dynamics in generation-wise non-overlapping population of two types of harvesters-one harvesting at a faster rate than the other-consuming a self-renewing resource capable of showing chaotic dynamics. In the light of our finding that sometimes chaos is confined exclusively to either the dynamics of the resource or that of the consumer fractions, an interesting scenario is realized: The resource state can keep oscillating chaotically, and hence, it does not vanish to result in the tragedy of the commons-extinction of the resource due to selfish indiscriminate exploitation-and yet the consumer population, whose dynamics depends directly on the state of the resource, may end up being composed exclusively of defectors, i.e., high harvesters. This appears non-intuitive because it is well known that prevention of tragedy of the commons usually requires substantial cooperation to be present.


Assuntos
Evolução Biológica , Teoria dos Jogos , Dinâmica Populacional , Comportamento Cooperativo
2.
Sci Rep ; 14(1): 12380, 2024 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-38811599

RESUMO

Chest Radiography is a non-invasive imaging modality for diagnosing and managing chronic lung disorders, encompassing conditions such as pneumonia, tuberculosis, and COVID-19. While it is crucial for disease localization and severity assessment, existing computer-aided diagnosis (CAD) systems primarily focus on classification tasks, often overlooking these aspects. Additionally, prevalent approaches rely on class activation or saliency maps, providing only a rough localization. This research endeavors to address these limitations by proposing a comprehensive multi-stage framework. Initially, the framework identifies relevant lung areas by filtering out extraneous regions. Subsequently, an advanced fuzzy-based ensemble approach is employed to categorize images into specific classes. In the final stage, the framework identifies infected areas and quantifies the extent of infection in COVID-19 cases, assigning severity scores ranging from 0 to 3 based on the infection's severity. Specifically, COVID-19 images are classified into distinct severity levels, such as mild, moderate, severe, and critical, determined by the modified RALE scoring system. The study utilizes publicly available datasets, surpassing previous state-of-the-art works. Incorporating lung segmentation into the proposed ensemble-based classification approach enhances the overall classification process. This solution can be a valuable alternative for clinicians and radiologists, serving as a secondary reader for chest X-rays, reducing reporting turnaround times, aiding clinical decision-making, and alleviating the workload on hospital staff.


Assuntos
COVID-19 , Radiografia Torácica , Índice de Gravidade de Doença , Humanos , COVID-19/diagnóstico por imagem , COVID-19/diagnóstico , Radiografia Torácica/métodos , SARS-CoV-2/isolamento & purificação , Pulmão/diagnóstico por imagem , Pulmão/patologia , Diagnóstico por Computador/métodos , Tomografia Computadorizada por Raios X/métodos , Algoritmos
3.
Phys Rev E ; 104(4-1): 044407, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34781515

RESUMO

The tragedy of the commons (TOC) is an unfortunate situation where a shared resource is exhausted due to uncontrolled exploitation by the selfish individuals of a population. Recently, the paradigmatic replicator equation has been used in conjunction with a phenomenological equation for the state of the shared resource to gain insight into the influence of the games on the TOC. The replicator equation, by construction, models a fixed infinite population undergoing microevolution. Thus, it is unable to capture any effect of the population growth and the carrying capacity of the population although the TOC is expected to be dependent on the size of the population. Therefore, in this paper, we present a mathematical framework that incorporates the density dependent payoffs and the logistic growth of the population in the eco-evolutionary dynamics modeling the game-resource feedback. We discover a bistability in the dynamics: a finite carrying capacity can either avert or cause the TOC depending on the initial states of the resource and the initial fraction of cooperators. In fact, depending on the type of strategic game-theoretic interaction, a finite carrying capacity can either avert or cause the TOC when it is exactly the opposite for the corresponding case with infinite carrying capacity.

4.
J Colloid Interface Sci ; 569: 244-253, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32114103

RESUMO

HYPOTHESIS: Lubricating fluid coated slippery (LCS) surfaces offer a new scope to study the evaporation of sessile drops due to pinning free motion of the three-phase contact line (TPCL). This work aims to experimentally demonstrate the different evaporation behavior of water and binary mixture drops on dry and LCS surfaces. EXPERIMENTS: Evaporation study on dry and LCS surfaces is performed by capturing top and side views of evaporating drops to extract various parameters which are subsequently used to distinguish between different evaporation modes. FINDINGS: Formation of a wetting ridge and cloaking of water drops on LCS surfaces affect the overall evaporation process and make it different compared to that on dry surfaces. Evaporation dynamics on LCS surfaces reveal that wetting ridge height of an evaporating drop varies non-monotonically compared to the drop height. Diffusion based theoretical model is used to predict the role of various system parameters on the evaporation process. In contrast to dry solid surfaces, where coffee ring effects are commonly observed towards the end of the evaporation process, LCS surfaces show the formation of a wrinkle like pattern of the lubricating fluid which disappears at long times.

5.
Interdiscip Sci ; 12(4): 537-546, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32193856

RESUMO

Many kinds of disease-related data are now available and researchers are constantly attempting to mine useful information out of these. Medical data are not always homogeneous and in structured form, and mostly they are time-stamped data. Thus, special care is required to prevent any kind of information loss during mining such data. Mining medical data is challenging as predicting the non-accurate result is often not acceptable in this domain. In this paper, we have analyzed a partially annotated coronary artery disease (CAD) dataset which was originally in a semi-structured form. We have created a set of some well-defined features from the dataset, and then build predictive models for CAD risk identification using different supervised learning algorithms. We then further enhanced the performances of the models using a feature selection technique. Experiments show that results are quite interesting, and are expected to help medical practitioners for investigating CAD risk in patients.


Assuntos
Doença da Artéria Coronariana , Algoritmos , Humanos
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