Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 11 de 11
Filtrar
1.
Sci Rep ; 14(1): 7903, 2024 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-38570552

RESUMO

In Public Goods Games (PGG), the temptation to free-ride on others' contributions poses a significant threat to the sustainability of cooperative societies. Therefore, societies strive to mitigate this through incentive systems, employing rewards and punishments to foster cooperative behavior. Thus, peer punishment, in which cooperators sanction defectors, as well as pool punishment, where a centralized punishment institution executes the punishment, is deeply analyzed in previous works. Although the literature indicates that these methods may enhance cooperation on social dilemmas under particular contexts, there are still open questions, for instance, the structural connection between graduated punishment and the monitoring of public goods games. Our investigation proposes a compulsory PGG framework under Panoptical surveillance. Inspired by Foucault's theories on disciplinary mechanisms and biopower, we present a novel mathematical model that scrutinizes the balance between the severity and scope of punishment to catalyze cooperative behavior. By integrating perspectives from evolutionary game theory and Foucault's theories of power and discipline, this research uncovers the theoretical foundations of mathematical frameworks involved in punishment and discipline structures. We show that well-calibrated punishment and discipline schemes, leveraging the panoptical effect for universal oversight, can effectively mitigate the free-rider dilemma, fostering enhanced cooperation. This interdisciplinary approach not only elucidates the dynamics of cooperation in societal constructs but also underscores the importance of integrating diverse methodologies to address the complexities of fostering cooperative evolution.


Assuntos
Comportamento Cooperativo , Punição , Modelos Teóricos , Teoria dos Jogos , Grupo Associado
2.
Med. clín. soc ; 7(3)dic. 2023.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1528990

RESUMO

Introducción: La transmisión viral a menudo se propaga en grupos, donde las infecciones se pueden rastrear hasta un caso índice o una ubicación geográfica, para así poder tomar medidas de prevención al respecto. Entender el perfil de transmisión del SARS-CoV-2 es esencial para desarrollar estrategias efectivas de prevención y control de la enfermedad. Objetivo: Determinar el perfil de transmisión del Sars-Cov-2, a partir de clúster con casos índices identificados, en la V región sanitaria (Caaguazu) del Paraguay, entre julio y octubre del 2020. Metodología: Se realizó un estudio observacional, descriptivo, de corte transversal, con fichas de notificación de casos de COVID-19 y resultados laboratoriales de la RT_PCR en pacientes diagnosticados con COVID-19 en la V Región Sanitaria entrejulio y octubre del 2020. Resultados: Fueron identificadas 703 personas con Sars-Cov-2 positivo. El 55,49 % de las personas no reconoció algún nexo de contagio. Con respecto al tipo de evento donde ocurrían con mayor frecuencia los contagios, ocurrieron en Eventos Sociales en 58,14 % de los casos y en el Ambiente Familiar en el 33,89 %. La transmisión secundaria se observó en el 17,40 % de los casos. Fueron identificados 58 Clústers, con una mediana de tamaño de los mismos de 3 (RIQ 2-4), y 267 personas (37,98 %) asociadas a los mismos. Discusión: La mayoría de las personas no reconocieron su nexo de contagio, sin embargo, en los que, si conocieron, se puede observar que la participación en eventos sociales fue el principal nexo, por lo que es fundamental realizar este tipo de ejercicios para hacer el seguimiento oportuno de los casos.


Introduction: Viral transmission often spreads in clusters, where infections can be traced to an index case or a geographic location, in order to take preventive measures in this regard, understanding the transmission profile of SARS-CoV-2 is essential. to develop effective disease prevention and control strategies. Objective: to determine the transmission profile of Sars-Cov-2, from clusters with identified index cases, in the V health region (Caaguazú) of Paraguay, between July and October 2020. Methodology: We carried out an observational, descriptive, cross-sectional study, with notification sheets of COVID-19 cases and laboratory results of the RT_PCR in patients diagnosed with COVID-19 in the V Sanitary Region between July and October 2020. Results: We identified 703 people with positive Sars-Cov-2. 55.49% of people did not recognize any contagion link. Regarding the type of event where infections occurred most frequently, was in Social Events in 58.14% of the cases and the Family Environment in 33.89%, secondary transmission was observed in 17.40% of the cases. 58 Clusters were identified, with a median size of 3 (IQR 2-4), and 267 people (37.98%) associated with them. Discussion: Most of the people did not recognize their contagion link, however, in those who did know, the main link was because they participated in social events, so it is essential to carry out this type of exercise to do timely follow-up. of the cases.

3.
HIV Med ; 24(9): 990-999, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37128161

RESUMO

INTRODUCTION: HIV prevalence among transgender women is high worldwide. The objectives of the present study were to estimate the current prevalence of HIV and identify factors associated with high HIV burden among transgender women in Paraguay. METHODS: Transgender women aged ≥15 years in four regions of Paraguay were recruited by Starfish sampling between February and March 2021. RESULTS: In total, 322 transgender women were included. Mean age was 31 years (range 15-67), and 102 had positive HIV test results (31.7%, 95% confidence interval [CI] 26.6-37.1). In multivariable analysis, factors associated with HIV infection were age at first intercourse ≤17 years (adjusted odds ratio [aOR] 5.47; 95% CI 1.05-28.42), >10 years difference in age with the last sexual partner (aOR 1.60; 95% CI 1.04-2.46), substance use (mostly cocaine) (aOR 3.00; 95% CI 1.47-6.12), higher risk perception (aOR 3.08; 95% CI 1.53-6.17), not testing for HIV (aOR 1.23; 95% CI 1.09-1.39), and accessed by a peer educator (aOR 3.86; 95% CI 1.77-8.38). CONCLUSIONS: Sexual debut as a minor and a large age difference with sexual partners are associated with high burden of HIV among transgender women in Paraguay. Our study corroborates the finding of cocaine use during sex as a risk factor for HIV. Prevention programmes must address structural and social vulnerabilities to stem the tragically high burden of HIV among transgender women.


Assuntos
Infecções por HIV , Soropositividade para HIV , HIV-1 , Pessoas Transgênero , Humanos , Feminino , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Infecções por HIV/epidemiologia , Paraguai/epidemiologia , Comportamento Sexual , Fatores de Risco , Prevalência
4.
PLoS One ; 18(4): e0284263, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37053225

RESUMO

INTRODUCTION: Dengue is transmitted by the Aedes aegypti mosquito as a vector, and a recent outbreak was reported in several districts of Lima, Peru. We conducted a modeling study to explain the transmission dynamics of dengue in three of these districts according to the demographics and climatology. METHODOLOGY: We used the weekly distribution of dengue cases in the Comas, Lurigancho, and Puente Piedra districts, as well as the temperature data to investigate the transmission dynamics. We used maximum likelihood minimization and the human susceptible-infected-recovered and vector susceptible-infected (SIR-SI) model with a Gaussian function for the infectious rate to consider external non-modeled variables. RESULTS/PRINCIPAL FINDINGS: We found that the adjusted SIR-SI model with the Gaussian transmission rate (for modelling the exogenous variables) captured the behavior of the dengue outbreak in the selected districts. The model explained that the transmission behavior had a strong dependence on the weather, cultural, and demographic variables while other variables determined the start of the outbreak. CONCLUSION/SIGNIFICANCE: The experimental results showed good agreement with the data and model results when a Bayesian-Gaussian transmission rate was employed. The effect of weather was also observed, and a strong qualitative relationship was obtained between the transmission rate and computed effective reproduction number Rt.


Assuntos
Aedes , Bivalves , Vírus da Dengue , Dengue , Animais , Humanos , Dengue/epidemiologia , Peru/epidemiologia , Teorema de Bayes , Mosquitos Vetores , Surtos de Doenças
5.
Int J STD AIDS ; 33(14): 1212-1222, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36257834

RESUMO

BACKGROUND: Our study aimed to measure HIV prevalence and associated risk factors among men who have sex with men (MSM) in three regions of Paraguay in 2020. METHODS: MSM were recruited for cross-sectional surveys in three regions of Paraguay using respondent-driven sampling. Interview were conducted face-to-face to collect demographic characteristics and risk and preventive behaviors. The analysis assessed HIV prevalence and associated risk factors in the three samples of MSM within each region. RESULTS: A total of 1,207 MSM were recruited, including 559 in Asunción-Central, 245 in Alto Paraná, and 403 in Caaguazú. HIV prevalence was 24.2% (95% CI 20.6-27.9) in Asunción-Central, 10.2% (95% CI 6.7-14.6) in Alto Paraná, and 3.2% (95% CI 1.7-5.4) in Caaguazú. In Asunción-Central, associations with HIV were age ≥25 years (1.86, 95% CI 1.15-3.00), being employed (1.82, 95% CI 1.07-3.11), self-reporting as homosexual (1.90, 95% CI 1.06-3.43), having sex with a known HIV-positive partner acquisition (4.19, 95% CI 2.37-7.43), self-perceived as being at higher risk for HIV acquisition (4.15, 95% CI 2.54-6.77), and able to access condoms and lubricants (1.82, 95% CI 1.08-3.05). In Alto Paraná, associations with HIV were self-reporting as homosexual (4.33, 95% CI 1.19-15.65) and having higher HIV knowledge (2.53, 95% CI 0.97-6.61). In Caaguazú, associations with HIV were self-reporting as homosexual (7.06, 95% CI 1.53-32.46) and being diagnosed with depression (4.68, 95% CI 0.89-24.43). CONCLUSIONS: HIV prevalence among MSM in Paraguay varied by region, being highest in the capital and major metropolitan area of Asunción-Central, followed by the border area of Alto Paraná. While being self-identified as homosexual was associated with HIV in all three regions, other associations differed, indicating prevention programs need to be tailored to the locale.


Assuntos
Infecções por HIV , Minorias Sexuais e de Gênero , Masculino , Humanos , Adulto , Homossexualidade Masculina , Comportamento Sexual , Prevalência , Estudos Transversais , Paraguai/epidemiologia , Infecções por HIV/diagnóstico , Fatores de Risco , Inquéritos e Questionários , Assunção de Riscos
6.
Entropy (Basel) ; 24(1)2021 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-35052090

RESUMO

Interaction between variables is often found in statistical models, and it is usually expressed in the model as an additional term when the variables are numeric. However, when the variables are categorical (also known as nominal or qualitative) or mixed numerical-categorical, defining, detecting, and measuring interactions is not a simple task. In this work, based on an entropy-based correlation measure for n nominal variables (named as Multivariate Symmetrical Uncertainty (MSU)), we propose a formal and broader definition for the interaction of the variables. Two series of experiments are presented. In the first series, we observe that datasets where some record types or combinations of categories are absent, forming patterns of records, which often display interactions among their attributes. In the second series, the interaction/non-interaction behavior of a regression model (entirely built on continuous variables) gets successfully replicated under a discretized version of the dataset. It is shown that there is an interaction-wise correspondence between the continuous and the discretized versions of the dataset. Hence, we demonstrate that the proposed definition of interaction enabled by the MSU is a valuable tool for detecting and measuring interactions within linear and non-linear models.

7.
J Biomol Struct Dyn ; 39(6): 2266-2277, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32238092

RESUMO

DNA topology changes continuously as replication proceeds. Unwinding of the DNA duplex by helicases is favored by negative supercoiling but it causes the progressive accumulation of positive supercoiling ahead of the fork. This torsional stress must be removed for the fork to keep advancing. Elimination of this positive torsional stress may be accomplished by topoisomerases acting solely ahead of the fork or simultaneously in the un-replicated and replicated regions after diffusion of some positive torsional strain from the un-replicated to the replicated regions by swivelling of the replication forks. In any case, once replication is completed fully replicated molecules are known to be heavily catenated and this catenation derives from pre-catenanes formed during replication. Although there is still controversy as to whether fork swiveling redistributes this positive torsional stress continuously or only as termination approaches, the forces that cause fork rotation and the generation of pre-catenanes are still poorly characterized. Here we used a numerical simulation, based on the worm-like chain model and the Metropolis Monte Carlo method, to study the interchange of supercoiling and pre-catenation in a naked circular DNA molecule of 4,440 bp partially replicated in vivo and in vitro. We propose that a dynamic gradient of torsional stress between the un-replicated and replicated regions drives fork swiveling allowing the interchange of supercoiling and pre-catenation.Communicated by Ramaswamy H. Sarma.


Assuntos
Replicação do DNA , DNA Super-Helicoidal , DNA/genética , Conformação de Ácido Nucleico
8.
Theor Popul Biol ; 135: 32-48, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32791081

RESUMO

Resistance to insecticide is considered nowadays one of the major threats to insect control, as its occurrence reduces drastically the efficiency of chemical control campaigns, and may also perturb the application of other control methods, like biological and genetic control. In order to account for the emergence and spread of such phenomenon as an effect of exposition to larvicide and/or adulticide, we develop in this paper a general time-continuous population model with two life phases, subsequently simplified through slow manifold theory. The derived models present density-dependent recruitment and mortality rates in a non-conventional way. We show that in absence of selection, they evolve in compliance with Hardy-Weinberg law; while in presence of selection and in the dominant or codominant cases, convergence to the fittest genotype occurs. The proposed mathematical models should allow for the study of several issues of importance related to the use of insecticides and other adaptive phenomena.


Assuntos
Resistência a Inseticidas , Inseticidas , Resistência a Inseticidas/genética
10.
J Biol Chem ; 290(22): 13725-35, 2015 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-25829493

RESUMO

The dynamics of DNA topology during replication are still poorly understood. Bacterial plasmids are negatively supercoiled. This underwinding facilitates strand separation of the DNA duplex during replication. Leading the replisome, a DNA helicase separates the parental strands that are to be used as templates. This strand separation causes overwinding of the duplex ahead. If this overwinding persists, it would eventually impede fork progression. In bacteria, DNA gyrase and topoisomerase IV act ahead of the fork to keep DNA underwound. However, the processivity of the DNA helicase might overcome DNA gyrase and topoisomerase IV. It was proposed that the overwinding that builds up ahead of the fork could force it to swivel and diffuse this positive supercoiling behind the fork where topoisomerase IV would also act to maintain replicating the DNA underwound. Putative intertwining of sister duplexes in the replicated region are called precatenanes. Fork swiveling and the formation of precatenanes, however, are still questioned. Here, we used classical genetics and high resolution two-dimensional agarose gel electrophoresis to examine the torsional tension of replication intermediates of three bacterial plasmids with the fork stalled at different sites before termination. The results obtained indicated that precatenanes do form as replication progresses before termination.


Assuntos
Replicação do DNA , DNA Bacteriano/genética , Catálise , Meios de Cultura/química , DNA Topoisomerase IV/química , DNA Super-Helicoidal/genética , Desenho de Fármacos , Eletroforese em Gel de Ágar , Escherichia coli/genética , Escherichia coli/metabolismo , Conformação de Ácido Nucleico , Hibridização de Ácido Nucleico , Plasmídeos/metabolismo
11.
Nucleic Acids Res ; 43(4): e24, 2015 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-25414338

RESUMO

We systematically varied conditions of two-dimensional (2D) agarose gel electrophoresis to optimize separation of DNA topoisomers that differ either by the extent of knotting, the extent of catenation or the extent of supercoiling. To this aim we compared electrophoretic behavior of three different families of DNA topoisomers: (i) supercoiled DNA molecules, where supercoiling covered the range extending from covalently closed relaxed up to naturally supercoiled DNA molecules; (ii) postreplicative catenanes with catenation number increasing from 1 to ∼15, where both catenated rings were nicked; (iii) knotted but nicked DNA molecules with a naturally arising spectrum of knots. For better comparison, we studied topoisomer families where each member had the same total molecular mass. For knotted and supercoiled molecules, we analyzed dimeric plasmids whereas catenanes were composed of monomeric forms of the same plasmid. We observed that catenated, knotted and supercoiled families of topoisomers showed different reactions to changes of agarose concentration and voltage during electrophoresis. These differences permitted us to optimize conditions for their separation and shed light on physical characteristics of these different types of DNA topoisomers during electrophoresis.


Assuntos
DNA Catenado/química , DNA Super-Helicoidal/química , DNA/química , Eletroforese em Gel de Ágar/métodos , Eletroforese em Gel Bidimensional/métodos , DNA/isolamento & purificação , DNA Catenado/isolamento & purificação , DNA Super-Helicoidal/isolamento & purificação , Conformação de Ácido Nucleico
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA