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1.
PLoS Comput Biol ; 20(5): e1012071, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38814981

RESUMO

Many social interactions happen indirectly via modifications of the environment, e.g. through the secretion of functional compounds or the depletion of renewable resources. Here, we derive the selection gradient on a quantitative trait affecting dynamical environmental variables that feed back on reproduction and survival in a finite patch-structured population subject to isolation by distance. Our analysis shows that the selection gradient depends on how a focal individual influences the fitness of all future individuals in the population through modifications of the environmental variables they experience, weighted by the neutral relatedness between recipients and the focal. The evolutionarily relevant trait-driven environmental modifications are formalized as the extended phenotypic effects of an individual, quantifying how a trait change in an individual in the present affects the environmental variables in all patches at all future times. When the trait affects reproduction and survival through a payoff function, the selection gradient can be expressed in terms of extended phenotypic effects weighted by scaled relatedness. We show how to compute extended phenotypic effects, relatedness, and scaled relatedness using Fourier analysis, which allow us to investigate a broad class of environmentally mediated social interactions in a tractable way. We use our approach to study the evolution of a trait controlling the costly production of some lasting commons (e.g. a common-pool resource or a toxic compound) that can diffuse in space and persist in time. We show that indiscriminate posthumous spite readily evolves in this scenario. More generally, whether selection favours environmentally mediated altruism or spite is determined by the spatial correlation between an individual's lineage and the commons originating from its patch. The sign of this correlation depends on interactions between dispersal patterns and the commons' renewal dynamics. More broadly, we suggest that selection can favour a wide range of social behaviours when these have carry-over effects in space and time.


Assuntos
Evolução Biológica , Interação Social , Biologia Computacional , Fenótipo , Animais , Meio Ambiente , Humanos
2.
Theor Popul Biol ; 155: 10-23, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38000514

RESUMO

Cooperation usually becomes harder to sustain as groups become larger because incentives to shirk increase with the number of potential contributors to collective action. But is this always the case? Here we study a binary-action cooperative dilemma where a public good is provided as long as not more than a given number of players shirk from a costly cooperative task. We find that at the stable polymorphic equilibrium, which exists when the cost of cooperation is low enough, the probability of cooperating increases with group size and reaches a limit of one when the group size tends to infinity. Nevertheless, increasing the group size may increase or decrease the probability that the public good is provided at such an equilibrium, depending on the cost value. We also prove that the expected payoff to individuals at the stable polymorphic equilibrium (i.e., their fitness) decreases with group size. For low enough costs of cooperation, both the probability of provision of the public good and the expected payoff converge to positive values in the limit of large group sizes. However, we also find that the basin of attraction of the stable polymorphic equilibrium is a decreasing function of group size and shrinks to zero in the limit of very large groups. Overall, we demonstrate non-trivial comparative statics with respect to group size in an otherwise simple collective action problem.


Assuntos
Comportamento Cooperativo , Teoria dos Jogos , Humanos , Evolução Biológica , Probabilidade
3.
J Am Chem Soc ; 145(4): 2461-2472, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36656167

RESUMO

A mixed-ligand phthalocyanine/porphyrin yttrium(III) radical double-decker complex (DD) was synthesized using the custom-made 5,10,15-tris(4-methoxyphenyl)-20-(4-((trimethylsilyl)ethynyl)phenyl)porphyrin. The trimethylsilyl functionality was then used to couple two such complexes into biradicals through rigid tethers. Glaser coupling was used to synthesize a short-tethered biradical (C1) and Sonogashira coupling to synthesize longer-tethered ones (C2 and C3). Field-swept echo-detected (FSED), saturation recovery, and spin nutation-pulsed electron paramagnetic resonance experiments revealed marked similarities of the magnetic properties of DD with those of the parent [Y(pc)2]• complex, both in the solid state and in CD2Cl2/CDCl3 4:1 frozen glasses. FSED experiments on the biradicals C2 and C3 revealed a spectral broadening with respect to the spectra of DD and [Y(pc)2]• assigned to the effect of dipolar interactions in solution. Apart from the main resonance, satellite features were also observed, which were simulated with dipole-dipole pairs of shortest distances, suggesting spin delocalization on the organic tether. FSED experiments on C1 yielded spectral line shapes that could not be simulated as the integration of the off-resonance echoes was complicated by field-dependent modulations. While, for all dimers, the on-resonance spin nutation experiments yielded Rabi oscillations of the same frequencies, off-resonance nutations on C1 yielded Rabi oscillations that could be assigned to a MS = -1 to MS = 0 transition within a S = 1 multiplet. The DFT calculations showed that the trans conformation of the complexes was significantly more stable than the cis one and that it induced a marked spin delocalization over the rigid organic tether. This "spin leakage" was most pronounced for the shortest biradical C1.

4.
Health Commun ; : 1-12, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37941378

RESUMO

This study investigated how visual messages conveying stereotype threat or lift influenced physical activity performance. Participants (N = 380) were exposed to a stereotype threat, lift, or control condition image and then engaged in a running task. Accelerometers recorded forward-backward movement, upward-downward movement, and sideways balance. Stereotype threat exposure increased state anxiety relative to the control condition. In addition, forward-backward movement was linked to state anxiety and participants' sex. Moreover, women exposed to stereotype threat who experienced increased state anxiety showed reduced forward-backward movement. Men exposed to stereotype lift displayed higher forward-backward movement. Additionally, stereotype threat visual message exposure increased sideways balance activity for women but not for men. Upward-downward movement was unaffected by stereotype threat or lift. We discuss theoretical and practical implications of how exposure to visual stereotypes can influence physical activity performance.

5.
Aten Primaria ; 55(5): 102604, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37002981

RESUMO

OBJECTIVE: To identify the association between glycemia control with level of diabetes knowledge, diabetes education, and lifestyle variables in patients with type 2 diabetes. DESIGN: Cross-sectional analytical study. SITE: Clinics of the Mexican Institute of Social Security (IMSS), Mexico. PARTICIPANTS: Patients with type 2 diabetes. MAIN MEASUREMENTS: Glycated hemoglobin (HbA1c), glucose, and lipid profile levels were measured from fasting venous blood samples. Assessment of disease knowledge was performed using the Diabetes Knowledge Questionnaire (DKQ-24). Systolic and diastolic blood pressure was measured. Weight and abdominal circumference were measured, as well as body composition using bioimpedance. Sociodemographic, clinical, and lifestyle variables were obtained. RESULTS: A total of 297 patients were included, sixty-seven percent (67%) were women with a median of six years since the diagnosis of diabetes. Only 7% of patients had adequate diabetes knowledge, and 56% had regular knowledge. Patients with adequate diabetes knowledge had a lower body mass index (p=0.016), lower percentage of fat (p=0.008), and lower fat mass (p=0.018); followed a diet (p=0.004) and had received diabetes education (p=0.002), and to obtain information about their illness (p=0.001). Patients with low levels of diabetes knowledge had a higher risk of HbA1c≥7% (OR: 4.68; 95% CI: 1.48,14.86; p=0.009), as well as those who did not receive diabetes education (OR: 2.17; 95% CI: 1.21-3.90; p=0.009) and those who did not follow a diet (OR: 2.37; 95% CI: 1.01,5.55; p=0.046). CONCLUSION: Inadequate knowledge of diabetes, lack of diabetes education, and dietary adherence are associated with poor glycemia control in patients with diabetes.


Assuntos
Diabetes Mellitus Tipo 2 , Hiperglicemia , Humanos , Feminino , Masculino , Diabetes Mellitus Tipo 2/complicações , Hemoglobinas Glicadas , Glicemia , Estudos Transversais
6.
Gac Med Mex ; 159(2): 110-115, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37094231

RESUMO

BACKGROUND: The impact of diabetes mellitus has been shown to be differentially expressed between social groups. OBJECTIVE: To estimate inequality gaps in diabetes mellitus mortality through absolute and relative measures according to geographic distribution and social conditions. MATERIAL AND METHODS: Diabetes mellitus-related deaths recorded in Mexico between 2010 and 2019 were analyzed, and inequality measurements at the state level were calculated by gender. RESULTS: National age-adjusted diabetes mellitus mortality rate showed an increase during the study period. CONCLUSION: The inequalities present in diabetes mortality should be considered for the design of health strategies.


ANTECEDENTES: Se ha demostrado que el impacto de la diabetes mellitus se expresa de manera diferenciada entre los grupos sociales. OBJETIVO: Estimar las brechas en la desigualdad en la mortalidad por diabetes mellitus a través de medidas absolutas y relativas según distribución geográfica y condiciones sociales. MATERIAL Y MÉTODOS: Se analizaron las muertes registradas en México por diabetes mellitus entre 2010 y 2019 y se calcularon las mediciones de desigualdad a nivel estatal por sexo. RESULTADOS: La tasa de mortalidad nacional por diabetes mellitus ajustada por edad mostró un incremento durante el periodo estudiado. CONCLUSIÓN: Las desigualdades presentes en la mortalidad por diabetes deben considerarse para el diseño de estrategias de salud.


Assuntos
Diabetes Mellitus , Humanos , Fatores Socioeconômicos , México , Grupo Social , Mortalidade
7.
Gac Med Mex ; 2023 Mar 01.
Artigo em Espanhol | MEDLINE | ID: mdl-36857699

RESUMO

Background: The impact of diabetes mellitus has been shown to be differentially expressed between social groups. Objective: To estimate inequality gaps in diabetes mellitus mortality through absolute and relative measures according to geographic distribution and social conditions. Material and methods: Diabetes mellitus-related deaths recorded in Mexico between 2010 and 2019 were analyzed, and inequality measurements at the state level were calculated by gender. Results: National age-adjusted diabetes mellitus mortality rate showed an increase during the study period. Conclusion: The inequalities present in diabetes mortality should be considered for the design of health strategies.


Antecedentes: Se ha demostrado que el impacto de la diabetes mellitus se expresa de manera diferenciada entre los grupos sociales. Objetivo: Estimar las brechas en la desigualdad en la mortalidad por diabetes mellitus a través de medidas absolutas y relativas según distribución geográfica y condiciones sociales. Material y métodos: Se analizaron las muertes registradas en México por diabetes mellitus entre 2010 y 2019 y se calcularon las mediciones de desigualdad a nivel estatal por sexo. Resultados: La tasa de mortalidad nacional por diabetes mellitus ajustada por edad mostró un incremento durante el periodo estudiado. Conclusión: Las desigualdades presentes en la mortalidad por diabetes deben considerarse para el diseño de estrategias de salud.

8.
Health Commun ; 37(2): 222-229, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-33054371

RESUMO

This study combined user-avatar similarity and Proteus effect predictions to incentivize physical activity. 305 participants ran while wearing accelerometers and a heart rate monitor. They were randomly assigned to onscreen motion-capturing avatars displaying either participant or stranger faces dressed in sports or formal clothes. Participants assigned to avatars displaying their own face showed increased cardiac frequency compared with those exposed to avatars with a stranger's face. Relative to the remaining conditions, participants assigned to avatars with their own face also wearing sports clothes showed increased cardiac frequency but participants assigned to avatars with a stranger's face wearing formal clothes showed decreased cardiac frequency. The results imply that user-avatar similarity and the Proteus effect can be harnessed to influence physical activity.


Assuntos
Exercício Físico , Interface Usuário-Computador , Humanos , Proteus
9.
Actas Esp Psiquiatr ; 50(6): 276-286, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36622715

RESUMO

There is a high prevalence of comorbid psychiatric disorders in alcohol abuse disorder. The presence of dual diagnosis in patients decreases the maintenance of abstinence and increases the likelihood of relapse, which makes treatment more complicated.


Assuntos
Alcoolismo , Transtornos Mentais , Transtornos Relacionados ao Uso de Substâncias , Humanos , Alcoolismo/complicações , Alcoolismo/terapia , Alcoolismo/epidemiologia , Diagnóstico Duplo (Psiquiatria) , Seguimentos , Comorbidade , Transtornos Relacionados ao Uso de Substâncias/psicologia , Transtornos Mentais/epidemiologia
10.
Proc Biol Sci ; 288(1949): 20210386, 2021 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-33878926

RESUMO

Eusociality, where largely unreproductive offspring help their mothers reproduce, is a major form of social organization. An increasingly documented feature of eusociality is that mothers induce their offspring to help by means of hormones, pheromones or behavioural displays, with evidence often indicating that offspring help voluntarily. The co-occurrence of maternal influence and offspring voluntary help may be explained by what we call the converted helping hypothesis, whereby maternally manipulated helping subsequently becomes voluntary. Such hypothesis requires that parent-offspring conflict is eventually dissolved-for instance, if the benefit of helping increases sufficiently over evolutionary time. We show that help provided by maternally manipulated offspring can enable the mother to sufficiently increase her fertility to transform parent-offspring conflict into parent-offspring agreement. This conflict-dissolution mechanism requires that helpers alleviate maternal life-history trade-offs, and results in reproductive division of labour, high queen fertility and honest queen signalling suppressing worker reproduction-thus exceptionally recovering diverse features of eusociality. As such trade-off alleviation seemingly holds widely across eusocial taxa, this mechanism offers a potentially general explanation for the origin of eusociality, the prevalence of maternal influence, and the offspring's willingness to help. Overall, our results explain how a major evolutionary transition can happen from ancestral conflict.


Assuntos
Evolução Biológica , Comportamento Social , Feminino , Feromônios , Reprodução , Solubilidade
11.
Physiol Plant ; 171(4): 728-738, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33159334

RESUMO

Light is a main environmental factor that determines leaf microclimate within the vine, as well as its photosynthesis and carbohydrate metabolism. This study aimed to examine the relationships between photosynthesis, carbohydrate metabolism, and the expression of related genes in leaves of grapevine grown under different radiation regimes. During the 2014/2015 growing season, an experiment was conducted on a Malbec vineyard (Vitis vinifera L.) in which four radiation exposure treatments were established on the leaves: (1) East, (2) West, (3) Sun, and (4) Shade (i.e., reduction in light intensity). Diurnal dynamics of photosynthesis and non-structural carbohydrates were measured and leaf export rates were calculated. Transcript profiles of leaf sugar transporters (VvHT1, VvHT3, VvSUC27), a sucrose phosphate synthase enzyme (VvSPS), and invertases (VvGIN1, VvCWI) were also examined. We showed that East and Sun leaves had higher daily photosynthetic and export rates than West leaves, which was mainly explained by the environmental conditions (air and leaf temperature, VPDleaf-air ) and leaf water status. Shade leaves accumulated less starch and soluble sugars than exposed leaves, which correlated with a higher expression of hexose transporters and invertases. The hypotheses that these sugars in Shade leaves would play a role as signaling molecules and/or have increased sink strength and phloem unloading are discussed. These results allow us to understand the physiological and molecular behavior of leaves exposed to different radiation regimes, which can be used to design appropriate vineyard management practices.


Assuntos
Folhas de Planta , Vitis , Carboidratos , Hexoses , Fotossíntese
12.
Actas Esp Psiquiatr ; 49(3): 114-123, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33969471

RESUMO

In recent decades the immigrant population has increased significantly in Western countries, which not only influences the former culturally but also in their alcohol consumption patterns. The course of immigration can cause social stress, which can lead to uprooting, frustration of their expectations or marginality, which are risk factors for an increase in alcohol consumption, possibly in order to face their different problems. The aims of this study are: to investigate the progression along two years of treatment of a sample of immigrant patients with Alcohol Use Disorder, to compare it with a sample of Spanish natives and to analyze the evolution of immigrant patients according to the geographical area of origin.


Assuntos
Alcoolismo , Emigrantes e Imigrantes , Emigração e Imigração , Seguimentos , Humanos , Fatores de Risco
13.
Am Nat ; 195(3): 524-533, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32097042

RESUMO

Egg trading-whereby simultaneous hermaphrodites exchange each other's eggs for fertilization-constitutes one of the few rigorously documented and most widely cited examples of direct reciprocity among unrelated individuals. Yet how egg trading may initially invade a population of nontrading simultaneous hermaphrodites is still unresolved. Here, we address this question with an analytical model that considers mate encounter rates and costs of egg production in a population that may include traders (who provide eggs for fertilization only if their partners also have eggs to reciprocate), providers (who provide eggs regardless of whether their partners have eggs to reciprocate), and withholders (cheaters who mate only in the male role and just use their eggs to elicit egg release from traders). Our results indicate that a combination of intermediate mate encounter rates, sufficiently high costs of egg production, and a sufficiently high probability that traders detect withholders (in which case eggs are not provided) is conducive to the evolution of egg trading. Under these conditions, traders can invade-and resist invasion from-providers and withholders alike. The prediction that egg trading evolves only under these specific conditions is consistent with the rare occurrence of this mating system among simultaneous hermaphrodites.


Assuntos
Evolução Biológica , Organismos Hermafroditas/fisiologia , Óvulo , Comportamento Sexual Animal , Animais , Feminino , Masculino , Modelos Biológicos , Reprodução
14.
Ann Bot ; 126(4): 647-660, 2020 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-31837221

RESUMO

BACKGROUND AND AIMS: Scaling from single-leaf to whole-canopy photosynthesis faces several complexities related to variations in light interception and leaf properties. To evaluate the impact of canopy strucuture on gas exchange, we developed a functional-structural plant model to upscale leaf processes to the whole canopy based on leaf N content. The model integrates different models that calculate intercepted radiation, leaf traits and gas exchange for each leaf in the canopy. Our main objectives were (1) to introduce the gas exchange model developed at the plant level by integrating the leaf-level responses related to canopy structure, (2) to test the model against an independent canopy gas exchange dataset recorded on different plant architectures, and (3) to quantify the impact of intra-canopy N distribution on crop photosynthesis. METHODS: The model combined a 3D reconstruction of grapevine (Vitis vinifera) canopy architecture, a light interception model, and a coupled photosynthesis and stomatal conductance model that considers light-driven variations in N distribution. A portable chamber device was constructed to measure whole-plant gas exchange to validate the model outputs with data collected on different training systems. Finally, a sensitivity analysis was performed to evaluate the impact on C assimilation of different N content distributions within the canopy. KEY RESULTS: By considering a non-uniform leaf N distribution within the canopy, our model accurately reproduced the daily pattern of gas exchange of different canopy architectures. The gain in photosynthesis permitted by the non-uniform compared with a theoretical uniform N distribution was about 18 %, thereby contributing to the maximization of C assimilation. By contrast, considering a maximal N content for all leaves in the canopy overestimated net CO2 exchange by 28 % when compared with the non-uniform distribution. CONCLUSIONS: The model reproduced the gas exchange of plants under different training systems with a low error (10 %). It appears to be a reliable tool to evaluate the impact of a grapevine training system on water use efficiency at the plant level.


Assuntos
Vitis , Fotossíntese , Folhas de Planta , Água
15.
BMC Public Health ; 20(1): 761, 2020 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-32448139

RESUMO

BACKGROUND: Health beliefs are relevant to consider in patients with type 2 diabetes since disease control depends mainly on the patient's behaviour. The aim of this study was to assess the association between health beliefs and glycated hemoglobin levels in Mexican patients with type 2 diabetes. METHODS: An analytical cross-sectional study was conducted, and 336 patients were included. Fasting blood levels of glycated hemoglobin, glucose, cholesterol; triglycerides, high-density lipoprotein cholesterol (HDL-c), and low-density lipoprotein cholesterol (LDL-c) were measured. Body fat percentage, weight, height; waist circumference, and systolic and diastolic blood pressures were also obtained. A previously validated self-administered questionnaire was used to assess the health beliefs with regards to non-pharmacological treatment. Health beliefs were classified as positive, neutral, and negative. RESULTS: The average age of patients was 54.7 ± 8.5 years, with a higher proportion of females (69%). The questionnaire had a good internal consistency with a Cronbach's alpha score of 0.83. More than 90% of patients attributed a health benefit to diet and exercise, 30 to 40% experienced barriers, and more than 80% had a perception of complications associated to uncontrolled diabetes. Patients with positive health beliefs had lower HbA1c levels (8.2 ± 1.7%) compared to those with neutral (9.0 ± 2.3%), or negative (8.8 ± 1.8%; p = 0.042). The LDL-c levels were lower (p = 0.03), and HDL-c levels were higher (0.002) in patients with positive heath beliefs. CONCLUSIONS: Positive health beliefs are associated with better metabolic control indicators in patients with type 2 diabetes.


Assuntos
Glicemia/análise , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Colesterol/sangue , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/metabolismo , Hemoglobinas Glicadas/análise , Lipoproteínas LDL/sangue , Triglicerídeos/sangue , Pressão Sanguínea , Índice de Massa Corporal , Estudos Transversais , Dieta , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Inquéritos Epidemiológicos , Humanos , Masculino , México , Pessoa de Meia-Idade
16.
Health Commun ; 35(6): 731-738, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-30887854

RESUMO

This study examined how exposure to online pictures of male models with different body sizes (thin, overweight) and physical attractiveness levels (attractive, unattractive) affected men's self-esteem (appearance- and weight-related self-esteem). Men exposed to attractive model pictures showed lower appearance-related self-esteem compared with those exposed to unattractive models. Among participants who were exposed to overweight models, those who were exposed to attractive models showed lower appearance- and weight-related self-esteem compared with those exposed to unattractive models. Men who saw themselves as more attractive or thinner than the models showed higher appearance- or weight-related self-esteem. The results imply a downward social comparison effect in which men reported higher self-esteem when exposed to model pictures they found less attractive or heavier compared with themselves.


Assuntos
Homens , Autoimagem , Imagem Corporal , Emoções , Humanos , Masculino
17.
J Theor Biol ; 457: 211-220, 2018 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-30172687

RESUMO

How the size of social groups affects the evolution of cooperative behaviors is a classic question in evolutionary biology. Here we investigate group size effects in the evolutionary dynamics of games in which individuals choose whether to cooperate or defect and payoffs do not depend directly on the size of the group. We find that increasing the group size decreases the proportion of cooperators at both stable and unstable rest points of the replicator dynamics. This implies that larger group sizes can have negative effects (by reducing the amount of cooperation at stable polymorphisms) and positive effects (by enlarging the basin of attraction of more cooperative outcomes) on the evolution of cooperation. These two effects can be simultaneously present in games whose evolutionary dynamics feature both stable and unstable rest points, such as public goods games with participation thresholds. Our theory recovers and generalizes previous results and is applicable to a broad variety of social interactions that have been studied in the literature.


Assuntos
Comportamento Animal , Evolução Biológica , Comportamento Cooperativo , Relações Interpessoais , Modelos Biológicos , Animais , Humanos , Dinâmica Populacional
18.
PLoS Comput Biol ; 13(11): e1005860, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29166656

RESUMO

Reproduction is a defining feature of living systems. To reproduce, aggregates of biological units (e.g., multicellular organisms or colonial bacteria) must fragment into smaller parts. Fragmentation modes in nature range from binary fission in bacteria to collective-level fragmentation and the production of unicellular propagules in multicellular organisms. Despite this apparent ubiquity, the adaptive significance of fragmentation modes has received little attention. Here, we develop a model in which groups arise from the division of single cells that do not separate but stay together until the moment of group fragmentation. We allow for all possible fragmentation patterns and calculate the population growth rate of each associated life cycle. Fragmentation modes that maximise growth rate comprise a restrictive set of patterns that include production of unicellular propagules and division into two similar size groups. Life cycles marked by single-cell bottlenecks maximise population growth rate under a wide range of conditions. This surprising result offers a new evolutionary explanation for the widespread occurrence of this mode of reproduction. All in all, our model provides a framework for exploring the adaptive significance of fragmentation modes and their associated life cycles.


Assuntos
Evolução Biológica , Fenômenos Fisiológicos Celulares/fisiologia , Estágios do Ciclo de Vida/fisiologia , Modelos Biológicos , Animais , Bactérias/citologia , Biologia Computacional , Reprodução/fisiologia
19.
PLoS Comput Biol ; 12(8): e1005059, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27513946

RESUMO

There has been much interest in studying evolutionary games in structured populations, often modeled as graphs. However, most analytical results so far have only been obtained for two-player or linear games, while the study of more complex multiplayer games has been usually tackled by computer simulations. Here we investigate evolutionary multiplayer games on graphs updated with a Moran death-Birth process. For cycles, we obtain an exact analytical condition for cooperation to be favored by natural selection, given in terms of the payoffs of the game and a set of structure coefficients. For regular graphs of degree three and larger, we estimate this condition using a combination of pair approximation and diffusion approximation. For a large class of cooperation games, our approximations suggest that graph-structured populations are stronger promoters of cooperation than populations lacking spatial structure. Computer simulations validate our analytical approximations for random regular graphs and cycles, but show systematic differences for graphs with many loops such as lattices. In particular, our simulation results show that these kinds of graphs can even lead to more stringent conditions for the evolution of cooperation than well-mixed populations. Overall, we provide evidence suggesting that the complexity arising from many-player interactions and spatial structure can be captured by pair approximation in the case of random graphs, but that it need to be handled with care for graphs with high clustering.


Assuntos
Evolução Biológica , Simulação por Computador , Comportamento Cooperativo , Teoria dos Jogos , Biologia Computacional , Humanos
20.
BMC Neurol ; 17(1): 161, 2017 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-28841856

RESUMO

BACKGROUND: Neuropathy is one of the major complications of type 2 diabetes mellitus. Our first aim was to determine the clinical characteristics of a population of diabetic patients with different types of neuropathy. Our next goal was to characterize the cytokine profile (IL-6 and IL-10), nerve growth factor (NGF) and circulating cell-adhesion molecules in these patients. Finally, we aimed to compare the renal function among the groups of neuropathic patients. METHODS: In a cross-sectional study, we included 217 diabetic patients classified in three groups: sensory polyneuropathy with hypoesthesia (DShP) or hyperesthesia (DSHP), and motor neuropathy (DMN). Two control groups were included: one of 26 diabetic non-neuropathic patients (DNN), and the other of 375 non-diabetic (ND) healthy subjects. The participants were attending to the Mexican Institute of Social Security. RESULTS: The circulating levels of NGF were significantly lower in diabetic patients, compared to healthy subjects. The range of IL-6 and IL-10 levels in neuropathic patients was higher than the control groups; however, several samples yielded null measurements. Neuropathic patients also showed increased circulating levels of the adhesion molecules ICAM, VCAM, and E-Selectin, compared to the ND group. Moreover, neuropathic patients showed reduced glomerular filtration rates compared to healthy subjects (82-103 ml/min per 1.73 m2, data as range from 25th-75th percentiles), especially in the group with DMN (45-76 ml/min per 1.73 m2). CONCLUSIONS: Some particular alterations in neuropathic patients included -but were not limited to- changes in circulating NGF, cell adhesion molecules, inflammation, and the worsening of the renal function. This study supports the need for further clinical surveillance and interventions considering a neuropathy-related basis.


Assuntos
Diabetes Mellitus Tipo 2 , Neuropatias Diabéticas , Indígenas Norte-Americanos/estatística & dados numéricos , Estudos Transversais , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/epidemiologia , Neuropatias Diabéticas/sangue , Neuropatias Diabéticas/epidemiologia , Humanos , Interleucina-10/sangue , Interleucina-6/sangue , México , Fator de Crescimento Neural/sangue
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