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1.
Public Health ; 185: 209-211, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32653630

RESUMO

OBJECTIVES: The objective of the study was to estimate associations between health locus of control (HLC) and mortality. STUDY DESIGN & METHODS: The public health survey in Scania 2008 was linked to the Swedish cause of death register. In this study of 10,757 men and 12,322 women aged 18-80 years, 421 men and 235 women died during the 5.3-year follow-up. Survival analyses were conducted. RESULTS: Respondents with only some or no internal HLC had significantly higher hazard rate ratios (HRRs) compared with respondents with high HLC. For women, the HRRs of those with low HLC did not significantly differ from the reference group after final adjustments for health-related behaviours. CONCLUSIONS: HLC is a predictor of mortality, and this association is to an important extent mediated by health-related behaviours.


Assuntos
Comportamentos Relacionados com a Saúde , Controle Interno-Externo , Mortalidade , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Atitude Frente a Saúde , Causas de Morte , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Estudos Prospectivos , Inquéritos e Questionários , Análise de Sobrevida , Suécia , Adulto Jovem
2.
Public Health ; 182: 77-79, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32199308

RESUMO

OBJECTIVES: To investigate associations between sexual identity and low leisure-time physical activity (LTPA). STUDY DESIGN: Cross-sectional study. METHODS: The 2012 public health survey was conducted with a postal questionnaire in southern Sweden with 28,029 respondents, aged 18-80 years. Analyses were conducted with logistic regressions. RESULTS: The prevalence of low LTPA among men and women were as follows: 13.9% and 12.3% among heterosexuals, 26.1% and 18.5% among bisexuals, 19.5% and 15.6% among homosexuals, 26.6% and 18.5% among others. Bisexual men and women and other men had higher odds ratio of low LTPA than heterosexuals in the final models, whereas gay and lesbian participants did not differ. CONCLUSIONS: The results should guide health promotion and prevention.


Assuntos
Exercício Físico , Atividades de Lazer , Comportamento Sexual/estatística & dados numéricos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Bissexualidade/estatística & dados numéricos , Estudos Transversais , Feminino , Inquéritos Epidemiológicos , Heterossexualidade/estatística & dados numéricos , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Atividade Motora , Prevalência , Minorias Sexuais e de Gênero/estatística & dados numéricos , Suécia , Adulto Jovem
3.
Public Health ; 178: 78-81, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31627055

RESUMO

OBJECTIVES: The purpose of this study was to analyse associations between sexual orientation and poor psychological health. STUDY DESIGN: This was a cross-sectional study. METHODS: The 2012 public health survey in Scania, Southern Sweden, is a cross-sectional population-based study with 28,029 participants aged 18-80 years. Logistic regression analyses were performed. RESULTS: The prevalence of poor psychological health (measured using the General Health Questionnaire [GHQ]-12) was 16.3% among men and 22.4% among women. Bisexual men and women had significantly higher odds ratios of poor psychological health throughout the multiple analyses than heterosexual individuals. In contrast, the odds ratios of poor psychological health among gay men and lesbian women were not significantly higher. CONCLUSIONS: Respondents with bisexual orientation have increased risk of poor psychological health.


Assuntos
Transtornos Mentais/epidemiologia , Comportamento Sexual/estatística & dados numéricos , Minorias Sexuais e de Gênero/psicologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Inquéritos Epidemiológicos , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Minorias Sexuais e de Gênero/estatística & dados numéricos , Suécia/epidemiologia , Adulto Jovem
4.
Public Health ; 170: 45-48, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30928612

RESUMO

OBJECTIVES: The aim was to investigate the association between baseline marital status and mortality using survival (Cox-regression) analysis. STUDY DESIGN: This is a prospective cohort study. METHODS: The public health survey by Scania in 2008 was linked to the Swedish cause of death register. This prospective cohort study includes 12,245 men and 14,969 women aged 18-80 years, and 538 men and 362 women of them died during the 5.3-year follow-up. RESULTS: Unmarried, divorced, and widowed men had significantly higher hazard rate ratios (HRRs) of all-cause mortality than married/cohabitating men. For women, the HRRs of these groups did not significantly differ from those of the married/cohabitating reference group. CONCLUSIONS: The results are in accordance with a previous study that only compared those living alone with those cohabitating.


Assuntos
Estado Civil/estatística & dados numéricos , Mortalidade/tendências , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Estudos Prospectivos , Análise de Sobrevida , Suécia/epidemiologia , Adulto Jovem
5.
Public Health ; 163: 42-45, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30059807

RESUMO

OBJECTIVES: To investigate associations between economic stress in childhood and suicide thoughts and attempts. STUDY DESIGN: The 2012 public health survey in Scania, Sweden, is a cross-sectional postal questionnaire study including 28,029 participants, aged 18-80 years. METHODS: Associations were analyzed in logistic regressions. RESULTS: A 12.1% prevalence of men and 15.5% of women had ever experienced suicide thoughts, while 3.2% of men and 5.3% of women had experienced suicide attempt. Roughly 24% had experienced less severe and 8% severe economic problems in childhood. Significant associations between economic stress in childhood and suicide thoughts and attempts remained throughout the age-adjusted and multiple adjusted analyses. CONCLUSIONS: Economic stress in childhood is associated with self-reported suicide thoughts and suicide attempts in an adult general population.


Assuntos
Adultos Sobreviventes de Eventos Adversos na Infância/psicologia , Pobreza/psicologia , Estresse Psicológico/psicologia , Ideação Suicida , Tentativa de Suicídio/estatística & dados numéricos , Adolescente , Adulto , Adultos Sobreviventes de Eventos Adversos na Infância/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Inquéritos e Questionários , Suécia/epidemiologia , Adulto Jovem
6.
Public Health ; 155: 129-132, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29353186

RESUMO

OBJECTIVES: The aim was to investigate associations between e-cigarette use and social and psychosocial factors and cigarette smoking, alcohol consumption, and narcotics use among adolescents attending 9th grade in primary school and 2nd grade in secondary school. STUDY DESIGN: Cross-sectional study. METHODS: The public health survey among adolescents in Scania in 2016 includes pupils in grades 9 and 2. The associations between e-cigarette use and lifestyle, social and psychosocial factors, and trust were investigated with logistic regressions. RESULTS: In 9th grade, 32% of male pupils and 27% of female pupils had ever used e-cigarettes, and in 2nd grade, 43% of males and 31% of females had ever used e-cigarettes. E-cigarette use was significantly associated with current smoking, snus (a moist powder tobacco product originating in Sweden) use, water pipe use, intensive alcohol consumption, and narcotics and also with psychosocial conditions related to home and parents, peers, and school. CONCLUSIONS: The prevalence of ever e-cigarette use was high among adolescents attending both grades. E-cigarette use was most strongly associated with health-related lifestyles. It was also associated with psychosocial factors such as study difficulties, school stress, problems talking with parents, and generalized trust.


Assuntos
Comportamento do Adolescente/psicologia , Comportamento Aditivo/psicologia , Vaping/psicologia , Vaping/estatística & dados numéricos , Adolescente , Consumo de Bebidas Alcoólicas/epidemiologia , Consumo de Bebidas Alcoólicas/psicologia , Fumar Cigarros/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Entorpecentes , Fatores de Risco , Instituições Acadêmicas , Suécia/epidemiologia
7.
Acta Paediatr ; 104(5): 508-13, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25619631

RESUMO

AIM: This study investigated the impact of being in family foster care on selected health determinants and participation in Child Health Services (CHS). METHODS: Two groups of 100 children, born between 1992 and 2008, were studied using data from Swedish Child Health Services for the preschool period up to the age of six. The first group had been in family foster care, and the controls, matched for age, sex and geographic location, had not. Descriptive statistics were used to describe differences in health determinants and participation in Child Health Services between the two groups. RESULTS: The foster care group had higher health risks, with lower rates of breastfeeding and higher levels of parental smoking. They were less likely to have received immunisations and attended key nurse or physician visits and speech and vision screening. Missing data for the phenylketonuria test were more common in children in family foster care. CONCLUSION: Children in family foster care were exposed to more health risks than the control children and had lower participation in the universal child health programme during the preschool period. These results call for secure access to high-quality preventive health care for this particularly vulnerable group of children.


Assuntos
Serviços de Saúde da Criança/estatística & dados numéricos , Cuidados no Lar de Adoção , Adulto , Aleitamento Materno/estatística & dados numéricos , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Estudos Retrospectivos , Suécia , Poluição por Fumaça de Tabaco/estatística & dados numéricos
8.
Diabetologia ; 56(7): 1494-502, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23568273

RESUMO

AIMS/HYPOTHESIS: The aim of this work was to investigate whether measurement of the mean common carotid intima-media thickness (CIMT) improves cardiovascular risk prediction in individuals with diabetes. METHODS: We performed a subanalysis among 4,220 individuals with diabetes in a large ongoing individual participant data meta-analysis involving 56,194 subjects from 17 population-based cohorts worldwide. We first refitted the risk factors of the Framingham heart risk score on the individuals without previous cardiovascular disease (baseline model) and then expanded this model with the mean common CIMT (CIMT model). The absolute 10 year risk for developing a myocardial infarction or stroke was estimated from both models. In individuals with diabetes we compared discrimination and calibration of the two models. Reclassification of individuals with diabetes was based on allocation to another cardiovascular risk category when mean common CIMT was added. RESULTS: During a median follow-up of 8.7 years, 684 first-time cardiovascular events occurred among the population with diabetes. The C statistic was 0.67 for the Framingham model and 0.68 for the CIMT model. The absolute 10 year risk for developing a myocardial infarction or stroke was 16% in both models. There was no net reclassification improvement with the addition of mean common CIMT (1.7%; 95% CI -1.8, 3.8). There were no differences in the results between men and women. CONCLUSIONS/INTERPRETATION: There is no improvement in risk prediction in individuals with diabetes when measurement of the mean common CIMT is added to the Framingham risk score. Therefore, this measurement is not recommended for improving individual cardiovascular risk stratification in individuals with diabetes.


Assuntos
Doenças Cardiovasculares/epidemiologia , Espessura Intima-Media Carotídea , Diabetes Mellitus/epidemiologia , Humanos , Infarto do Miocárdio/epidemiologia , Fatores de Risco , Acidente Vascular Cerebral/epidemiologia
9.
Public Health ; 126(9): 790-5, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22925881

RESUMO

OBJECTIVES: To investigate the association between marital status and lack of internal health locus of control (HLC), taking economic stress and trust into account. STUDY DESIGN: Cross-sectional study. METHODS: The public health survey Skåne 2008 is a postal questionnaire study (55% participation rate). A random sample was invited to participate, and 28,198 individuals aged 18-80 years agreed. Logistic regression models were used to discern associations between marital status and lack of internal HLC. The multiple regression analyses included age, country of birth, education, economic stress and 'horizontal' trust. RESULTS: In total, 33.7% of the men and 31.8% of the women lacked internal HLC. After age-adjustments, the unmarried and divorced men and the widowed women displayed significantly higher odds ratios of lack of internal HLC. The significantly higher odds ratios only remained for unmarried men throughout the multiple analyses. In contrast, divorced women had significantly lower odds ratios of lack of internal HLC than married women after adjustments for economic stress. CONCLUSIONS: Health promotion regarding HLC and related behaviours should consider men and women who are not cohabiting. Health promotion should particularly consider unmarried men due to their higher propensity to lack internal HLC. The economic conditions and exposure to economic stress among widowed and divorced women should also be highlighted.


Assuntos
Comportamentos Relacionados com a Saúde , Controle Interno-Externo , Estado Civil , Apoio Social , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Inquéritos Epidemiológicos , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores Socioeconômicos , Suécia , Confiança , Adulto Jovem
10.
Vaccine ; 40(46): 6640-6648, 2022 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-36210254

RESUMO

BACKGROUND: Studies on sociodemographic disparities in Covid-19 vaccination uptake in the general population are still limited and mostly focused on older adults. This study examined sociodemographic differences in Covid-19 vaccination uptake in the total Swedish population aged 18-64 years. METHODS: National Swedish register data within the SCIFI-PEARL project were used to cross-sectionally investigate sociodemographic differences in Covid-19 vaccination among Swedish adults aged 18-64 years (n = 5,987,189) by 12 October 2021. Using logistic regression models, analyses were adjusted for sociodemographic factors, region of residence, history of Covid-19, and comorbidities. An intersectional analysis approach including several cross-classified subgroups was used to further address the complexity of sociodemographic disparities in vaccination uptake. FINDINGS: By 12 October 2021, 76·0% of the Swedish population 18-64 years old had received at least two doses of Covid-19 vaccine, an additional 5·5% had received only one dose, and 18·5% were non-vaccinated. Non-vaccinated individuals were, compared to vaccinated, more often younger, male, had a lower income, were not gainfully employed, and/or were born outside Sweden. The social patterning for vaccine dose two was similar, but weaker, than for dose one. After multivariable adjustments, findings remained but were attenuated indicating the need to consider different sociodemographic factors simultaneously. The intersectional analysis showed a large variation in vaccine uptake ranging from 32% to 96% in cross-classified subgroups, reflecting considerable sociodemographic heterogeneity in vaccination coverage. INTERPRETATION: Our study, addressing the entire Swedish population aged 18-64 years, showed broad sociodemographic disparities in Covid-19 vaccine uptake but also wide heterogeneities in coverage. The intersectional analysis approach indicates that focusing on specific sociodemographic factors in isolation and group average risks without considering the heterogeneity within such groups will risk missing the full variability of vaccine coverage. FUNDING: SciLifeLab / Knut & Alice Wallenberg Foundation, Swedish Research Council, Swedish government ALF agreement, FORMAS.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Humanos , Masculino , Idoso , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Suécia/epidemiologia , COVID-19/epidemiologia , COVID-19/prevenção & controle , Vacinação , Cobertura Vacinal
11.
J Psychosom Res ; 152: 110663, 2021 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-34798453

RESUMO

BACKGROUND: There is an increasing interest in the potential health benefits of positive psychological states, especially with regard to cardiovascular health. Life satisfaction is thought to be a constituent component of psychological well-being; however, among the few previous studies that have investigated its associations with early stages of the cardiovascular disease process, only one small study has focused on coronary atherosclerosis. The present study aimed to explore associations between life satisfaction and coronary artery disease. METHODS: The study used cross-sectional data from SCAPIS Malmö (n = 6251 randomly selected men and women, aged 50-64 years), including assessment of life satisfaction and coronary artery calcification. Adjustments were made for sociodemographic factors, depression, and cardiovascular risk factors as assessed with the SCORE instrument. RESULTS: Higher levels of life satisfaction were associated with lower odds of increased coronary artery calcification. This association persisted after adjusting for sociodemographic factors and depression, but lost significance after adjusting for cardiovascular risk factors. Sub-analyses revealed a significant dose-response relationship between higher life satisfaction and lower grade of coronary calcification in all investigated coronary artery regions. CONCLUSION: In this population-based sample, life satisfaction was associated with better coronary artery health. However, this association was largely explained by cardiovascular risk factors, indicating that life satisfaction is linked to coronary atherosclerosis through a decreased load of cardiovascular risk factors.

12.
Phys Rev Lett ; 104(4): 040603, 2010 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-20366697

RESUMO

The distribution of information is essential for a living system's ability to coordinate and adapt. Random walkers are often used to model this distribution process and, in doing so, one effectively assumes that information maintains its relevance over time. But the value of information in social and biological systems often decays and must continuously be updated. To capture the spatial dynamics of aging information, we introduce time walkers. A time walker moves like a random walker, but interacts with traces left by other walkers, some representing older information, some newer. The traces form a navigable information landscape which we visualize as a river network. We quantify the dynamical properties of time walkers, and the quality of the information left behind, on a two-dimensional lattice. We show that searching in this landscape is superior to random searching.

13.
J Psychosom Res ; 132: 109973, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32146250

RESUMO

BACKGROUND: Increasing psychosocial stress may underlie contemporary obesity trends. We investigate cross-sectional and prospective associations between negative life events (NLEs) and anthropometric indicators, and whether these are explained by lifestyle, depression and sleeping problems. METHODS: Participants in the Swedish INTERGENE cohort answered questions about ten types of NLE, and indicated whether they occurred during the last year or earlier (2001-04, n = 2706). Body mass index (BMI) and waist-to-hip ratio (WHR) were measured at baseline, and at follow-up (2014-16, n = 974). Numbers of recent and distant NLE were related to anthropometric variables using linear models including age, sex, and education, and further adjusted for lifestyle, and psychological problems. Prospective models were adjusted for baseline anthropometric values. RESULTS: Participants reported on average 3.6 types of NLEs, of which 70% were experienced more than one year ago. At baseline, distant but not recent NLEs were associated with higher values of both BMI and WHR. These associations were explained in part by lifestyle and depression assessed at baseline. Recent but not distant NLEs predicted gain in BMI, 0.19 (0.07, 0.30) kg/m2, and WHR, 0.005 (0.002, 0.007), per event and independent of baseline covariates. The largest associations were seen for job insecurity and financial worries, with 0.35 (0.17, 0.52) kg/m2 increase in BMI corresponding to approximately 1.2 kg per event, in both sexes. CONCLUSION: We observed positive associations between NLEs and weight gain over 13 years including signs of latency and recovery regarding adverse weight development.


Assuntos
Estilo de Vida/etnologia , Aumento de Peso/genética , Adulto , Idoso , Estudos de Coortes , Estudos Transversais , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Suécia
14.
J Psychosom Res ; 129: 109888, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31835155

RESUMO

OBJECTIVE: The contemporary increase in psychological distress observed in many countries is, by itself, a public health issue of great concern. The present study aims to investigate associations between self-reported negative emotional states and negative life events, and cardiovascular disease (CVD). METHODS: Prospective cohort study based on the Swedish INTERGENE cohort comprising 3614 men and women, aged 25 to 75. Baseline examinations during 2001-2004 included self-rating depression and anxiety scales, life stress, as well as a wide range of physiological and behavioral parameters, which allowed for relevant adjustments. Cox proportion hazard was used to predict incident CVD, CVD mortality as well as all-cause mortality. RESULTS: The results showed a dose-response relationship between depressiveness, anxiety and negative life events on the one hand, and increased risk of CVD. Most of these associations persisted in the fully adjusted models. Furthermore, the youngest age group (25-44 years) generally showed the highest prevalence of psychosocial distress, and also had the highest risks of incident CVD with regard to depression and anxiety. CONCLUSION: The associations between psychological distress and later life cardiovascular disease calls for enhanced public health efforts aiming at ameliorating psychological health, not least in younger age groups.


Assuntos
Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/psicologia , Emoções/fisiologia , Estresse Psicológico/epidemiologia , Adulto , Estudos de Coortes , Feminino , Humanos , Masculino , Estudos Prospectivos , Fatores de Risco
15.
Phys Rev E Stat Nonlin Soft Matter Phys ; 79(2 Pt 2): 026111, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19391810

RESUMO

To investigate the role of information flow in group formation, we introduce a model of communication and social navigation. We let agents gather information in an idealized network society and demonstrate that heterogeneous groups can evolve without presuming that individuals have different interests. In our scenario, individuals' access to global information is constrained by local communication with the nearest neighbors on a dynamic network. The result is reinforced interests among like-minded agents in modular networks; the flow of information works as a glue that keeps individuals together. The model explains group formation in terms of limited information access and highlights global broadcasting of information as a way to counterbalance this fragmentation. To illustrate how the information constraints imposed by the communication structure affects future development of real-world systems, we extrapolate dynamics from the topology of four social networks.


Assuntos
Biofísica/métodos , Comunicação , Comportamento Social , Algoritmos , Simulação por Computador , Humanos , Relações Interpessoais , Modelos Biológicos , Modelos Teóricos
16.
J Epidemiol Community Health ; 62(1): 62-8, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18079335

RESUMO

STUDY OBJECTIVE: Previous studies of neighbourhood effects on ischaemic heart disease (IHD) have used census or administrative data to characterise the residential context, most commonly its socioeconomic level. Using the ecometric approach to define neighbourhood social interaction variables that may be relevant to IHD, neighbourhood social cohesion and safety were examined to see how they related to acute myocardial infarction (AMI) mortality, after adjustment for individual and neighbourhood confounders. DESIGN: To construct social interaction variables, multilevel models were used to aggregate individual perceptions of safety and cohesion at the neighbourhood level. Linking data from the Health Survey in Scania, Sweden, and the Population, Hospital, and Mortality Registers, multilevel survival models were used to investigate determinants of AMI mortality over a three year and nine month period. PARTICIPANTS: 7791 Individuals aged 45 years and over. MAIN RESULTS: The rate of AMI mortality increased with decreasing neighbourhood safety and cohesion. After adjustment for individual health and socioeconomic variables, low neighbourhood cohesion, and to a lesser extent low safety, were associated with higher AMI mortality. Neighbourhood cohesion effects persisted after adjustment for various neighbourhood confounding factors (income, population density, percentage of residents from low-income countries, residential stability) and distance to the hospital. There was some evidence that neighbourhood cohesion effects on AMI mortality were caused by effects on one-day case-fatality, rather than on incidence. CONCLUSIONS: Beyond commonly evoked effects of the physical environment, neighbourhood social interaction patterns may have a decisive influence on IHD, with a particularly strong effect on survival after AMI.


Assuntos
Relações Interpessoais , Infarto do Miocárdio/mortalidade , Características de Residência , Idoso , Idoso de 80 Anos ou mais , Métodos Epidemiológicos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/etiologia , Infarto do Miocárdio/psicologia , Segurança/estatística & dados numéricos , Suécia/epidemiologia
17.
Phys Rev E Stat Nonlin Soft Matter Phys ; 74(1 Pt 2): 016108, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16907152

RESUMO

This paper introduces a model of self-organization between communication and topology in social networks, with a feedback between different communication habits and the topology. To study this feedback, we let agents communicate to build a perception of a network and use this information to create strategic links. We observe a narrow distribution of links when the communication is low and a system with a broad distribution of links when the communication is high. We also analyze the outcome of chatting, cheating, and lying, as strategies to get better access to information in the network. Chatting, although only adopted by a few agents, gives a global gain in the system. Contrary, a global loss is inevitable in a system with too many liars.

18.
Atherosclerosis ; 179(2): 325-31, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15777549

RESUMO

BACKGROUND: The carotid intima-media thickness (IMT) has been associated with incidence of stroke. Whether this association is independent of carotid plaque is controversial. METHODS AND RESULTS: The associations among B-mode ultrasound determined common carotid IMT, carotid plaque (focal IMT>1.2mm) and incident stroke, were investigated in 5163 Swedish middle-aged men and women over a median follow-up of 7 years. Age and sex-adjusted carotid IMT, and carotid plaque were significantly (p<0.05) related to future stroke. Adjustment for cardiovascular risk factors generally reduced the hazard rate ratios, however more prominently so with regard to the carotid measure of plaque than with IMT. The associations between carotid IMT and stroke remained after adjustment for presence of carotid plaque, and graded associations between carotid IMT and stroke was found both among those with and without carotid plaque. CONCLUSIONS: In this population-based study, common carotid IMT was associated with incidence of stroke. This relation was independent of presence of carotid plaque.


Assuntos
Artérias Carótidas/patologia , Artérias Carótidas/ultraestrutura , Acidente Vascular Cerebral/etiologia , Túnica Íntima/patologia , Túnica Íntima/ultraestrutura , Arteriosclerose/complicações , Artérias Carótidas/diagnóstico por imagem , Feminino , Seguimentos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Acidente Vascular Cerebral/epidemiologia , Túnica Íntima/diagnóstico por imagem , Ultrassonografia de Intervenção
19.
Phys Rev E Stat Nonlin Soft Matter Phys ; 71(6 Pt 2): 066111, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16089824

RESUMO

We study navigation with limited information in networks and demonstrate that many real-world networks have a structure which can be described as favoring communication at short distance at the cost of constraining communication at long distance. This feature, which is robust and more evident with limited than with complete information, reflects both topological and possibly functional design characteristics. For example, the characteristics of the networks studied derived from a city and from the Internet are manifested through modular network designs. We also observe that directed navigation in typical networks requires remarkably little information on the level of individual nodes. By studying navigation or specific signaling, we take a complementary approach to the common studies of information transfer devoted to broadcasting of information in studies of virus spreading and the like.

20.
Phys Rev E Stat Nonlin Soft Matter Phys ; 72(4 Pt 2): 046117, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16383478

RESUMO

We investigate the searchability of complex systems in terms of their interconnectedness. Associating searchability with the number and size of branch points along the paths between the nodes, we find that scale-free networks are relatively difficult to search, and thus that the abundance of scale-free networks in nature and society may reflect an attempt to protect local areas in a highly interconnected network from nonrelated communication. In fact, starting from a random node, real-world networks with higher order organization like modular or hierarchical structure are even more difficult to navigate than random scale-free networks. The searchability at the node level opens the possibility for a generalized hierarchy measure that captures both the hierarchy in the usual terms of trees as in military structures, and the intrinsic hierarchical nature of topological hierarchies for scale-free networks as in the Internet.

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