Agent-Based Modeling: An Innovative Opportunity for Population-Based Oral Health Promotion

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Friendship Network and Dental Brushing Behavior among Middle School Students: An Agent Based Modeling Approach.

By using a standard questionnaire, the level of dental brushing frequency was assessed among 201 adolescent female middle school students in Tehran. The initial assessment was repeated after 5 months, in order to observe the dynamics in dental health behavior level. Logistic Regression model was used to evaluate the correlation among individuals' dental health behavior in their social network. A significant correlation on dental brushing habits was detected among groups of friends. This correlation was further spread over the network within the 5 months period. Moreover, it was identified that the average brushing level was improved within the 5 months period. Given that there was a significant correlation between social network's nodes' in-degree value, and brushing level, it was suggested that the observed improvement was partially due to more popularity of individuals with better tooth brushing habit. Agent Based Modeling (ABM) was used to demonstrate the dynamics of dental brushing frequency within a sample of friendship network. Two models with static and dynamic assumptions for the network structure were proposed. The model with dynamic network structure successfully described the dynamics of dental health behavior. Based on this model, on average, every 43 weeks a student changes her brushing habit due to learning from her friends. Finally, three training scenarios were tested by these models in order to evaluate their effectiveness. When training more popular students, considerable improvement in total students' brushing frequency was demonstrated by simulation results

Alternating electric fields can improve chemotherapy treatment efficacy in blood cancer cell U937 (non-adherent cells)

Abstract Background Recent achievements in cancer therapy are the use of alternating electrical fields at intermediate frequencies (100–300 kHz) and low intensities (1–3 V/cm), which specifically target cell proliferation while affecting different cellular activities depending on the frequency used. Methods In this article, we examine the effect of electric fields on spherical suspended cells and propose the combination of Daunorubicin, a chemotherapy agent widely used in the treatment of acute myeloid leukemia, with electric field exposure. U937 cells were subjected to an electric field with a frequency of 200 kHz and an intensity of 0.75 V/cm, or to a combination of Daunorubicin and electric field exposure, resulting in a significant reduction in cell proliferation. Furthermore, the application of an electric field to U937 cells increased Daunorubicin uptake. Results Apoptosis and DNA damage were induced by the electric field or in conjunction with Daunorubicin. Notably, normal cells exposed to an electric field did not show significant damage, indicating a selective effect on dividing cancer cells (U937). Moreover, the electric field affects the U937 cell line either alone or in combination with Daunorubicin. This effect may be due to increased membrane permeability. Conclusions Our findings suggest that the use of electric fields at intermediate frequencies and low intensities, either alone or in combination with Daunorubicin, has potential as a selective anti-cancer therapy for dividing cancer cells, particularly in the treatment of acute myeloid leukemia. Further research is needed to fully understand the underlying mechanisms and to optimize the use of this therapy

Correlation between agents’ brushing frequency and their friends in different levels of friendship (distance in the network).

<p>Correlation between agents’ brushing frequency and their friends in different levels of friendship (distance in the network).</p

Frequency analysis of statistics characterizing the friendship relations.

<p>Frequency analysis of statistics characterizing the friendship relations.</p

Logistic regression model for the relationship between an agent’s brushing frequency level and the degree of her incoming connections, results are based on the data from the first round of assessment.

<p>Logistic regression model for the relationship between an agent’s brushing frequency level and the degree of her incoming connections, results are based on the data from the first round of assessment.</p

Comparison of the cross correlation values for different friendship level of empirical data and simulation.

<p>(a) static network model and (b) dynamic network model. The u, as probability of changing an agent’s brushing frequency habit in a week, was assumed to be 0.02 and 0.023 for static and dynamic network model respectively.</p

Schematic of the Agent Based Model.

<p><b>(a)</b> Four different status of agent’s brushing frequency. Nodes’ color shows the level of the agent’s brushing frequency of brushing and node’s size shows her popularity. <b>(b)</b> Changing a student’s friendship relations in the network (dynamic network model).</p

Simulation result of the three scenarios.

<p>Simulation result of the three scenarios.</p

Frequency analysis of students with different levels of brushing frequency.

<p>Frequency analysis of students with different levels of brushing frequency.</p