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1.
Nutrients ; 15(20)2023 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-37892418

RESUMO

Obesity in adolescence is associated with significant morbidity and predisposes adolescents to the development of cardiovascular disease (CVD). Although a number of traditional CVD risk factors have been identified in youth, limited data exist regarding non-traditional CVD risk factors. In 89 adolescents with metabolic syndrome (MetS), with 60 age-, gender-, and BMI-matched controls, we determined the non-traditional CVD risk factors (hs-CRP, TG/HDL ratio, ApoB/ApoA1 ratio, NAFLD) in order to investigate whether they may be used as biomarkers for predicting future CVD, and we evaluated their response to the implementation of a multidisciplinary, personalized, lifestyle intervention program for 1 year. We demonstrated that the TG/HDL ratio, IL-2, IL-6, IL-17A, and INF-γ were significantly increased in subjects with MetS than in controls, and may be used as biomarkers to predict future CVD. Subjects with MetS had an increased mean carotid intima-media thickness (cIMT) and prevalence of NAFLD than the controls, while the prevalence of NAFLD correlated strongly with cIMT and IL-6 concentrations. Most of the non-traditional cardiovascular risk factors improved following the implementation of a lifestyle intervention program. These findings indicate that adolescents with MetS may have a greater risk for developing atherosclerosis early in life, while early lifestyle intervention is crucial for preventing the arteriosclerotic process in youth.


Assuntos
Doenças Cardiovasculares , Síndrome Metabólica , Hepatopatia Gordurosa não Alcoólica , Obesidade Infantil , Adolescente , Humanos , Síndrome Metabólica/complicações , Síndrome Metabólica/epidemiologia , Obesidade Infantil/complicações , Obesidade Infantil/epidemiologia , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/complicações , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Hepatopatia Gordurosa não Alcoólica/complicações , Fatores de Risco , Espessura Intima-Media Carotídea , Interleucina-6 , Fatores de Risco de Doenças Cardíacas , Biomarcadores
2.
Philos Trans R Soc Lond B Biol Sci ; 378(1874): 20220068, 2023 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-36802781

RESUMO

Most studies of collective animal behaviour rely on short-term observations, and comparisons of collective behaviour across different species and contexts are rare. We therefore have a limited understanding of intra- and interspecific variation in collective behaviour over time, which is crucial if we are to understand the ecological and evolutionary processes that shape collective behaviour. Here, we study the collective motion of four species: shoals of stickleback fish (Gasterosteus aculeatus), flocks of homing pigeons (Columba livia), a herd of goats (Capra aegagrus hircus) and a troop of chacma baboons (Papio ursinus). First, we describe how local patterns (inter-neighbour distances and positions), and group patterns (group shape, speed and polarization) during collective motion differ across each system. Based on these, we place data from each species within a 'swarm space', affording comparisons and generating predictions about the collective motion across species and contexts. We encourage researchers to add their own data to update the 'swarm space' for future comparative work. Second, we investigate intraspecific variation in collective motion over time and provide guidance for researchers on when observations made over different time scales can result in confident inferences regarding species collective motion. This article is part of a discussion meeting issue 'Collective behaviour through time'.


Assuntos
Columbidae , Smegmamorpha , Animais , Comportamento Animal , Movimento (Física) , Evolução Biológica
3.
R Soc Open Sci ; 9(2): 211898, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35223068

RESUMO

Complex patterns of collective behaviour may emerge through self-organization, from local interactions among individuals in a group. To understand what behavioural rules underlie these patterns, computational models are often necessary. These rules have not yet been systematically studied for bird flocks under predation. Here, we study airborne flocks of homing pigeons attacked by a robotic falcon, combining empirical data with a species-specific computational model of collective escape. By analysing GPS trajectories of flocking individuals, we identify two new patterns of collective escape: early splits and collective turns, occurring even at large distances from the predator. To examine their formation, we extend an agent-based model of pigeons with a 'discrete' escape manoeuvre by a single initiator, namely a sudden turn interrupting the continuous coordinated motion of the group. Both splits and collective turns emerge from this rule. Their relative frequency depends on the angular velocity and position of the initiator in the flock: sharp turns by individuals at the periphery lead to more splits than collective turns. We confirm this association in the empirical data. Our study highlights the importance of discrete and uncoordinated manoeuvres in the collective escape of bird flocks and advocates the systematic study of their patterns across species.

4.
PLoS Comput Biol ; 18(1): e1009772, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-35007287

RESUMO

Bird flocks under predation demonstrate complex patterns of collective escape. These patterns may emerge by self-organization from local interactions among group-members. Computational models have been shown to be valuable for identifying what behavioral rules may govern such interactions among individuals during collective motion. However, our knowledge of such rules for collective escape is limited by the lack of quantitative data on bird flocks under predation in the field. In the present study, we analyze the first GPS trajectories of pigeons in airborne flocks attacked by a robotic falcon in order to build a species-specific model of collective escape. We use our model to examine a recently identified distance-dependent pattern of collective behavior: the closer the prey is to the predator, the higher the frequency with which flock members turn away from it. We first extract from the empirical data of pigeon flocks the characteristics of their shape and internal structure (bearing angle and distance to nearest neighbors). Combining these with information on their coordination from the literature, we build an agent-based model adjusted to pigeons' collective escape. We show that the pattern of turning away from the predator with increased frequency when the predator is closer arises without prey prioritizing escape when the predator is near. Instead, it emerges through self-organization from a behavioral rule to avoid the predator independently of their distance to it. During this self-organization process, we show how flock members increase their consensus over which direction to escape and turn collectively as the predator gets closer. Our results suggest that coordination among flock members, combined with simple escape rules, reduces the cognitive costs of tracking the predator while flocking. Such escape rules that are independent of the distance to the predator can now be investigated in other species. Our study showcases the important role of computational models in the interpretation of empirical findings of collective behavior.


Assuntos
Columbidae/fisiologia , Reação de Fuga/fisiologia , Comportamento de Massa , Animais , Biologia Computacional , Simulação por Computador , Especificidade da Espécie
5.
Nutrients ; 13(8)2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-34444842

RESUMO

Leucocyte telomere length (LTL) is a robust marker of biological aging and is associated with obesity and cardiometabolic risk factors in childhood and adolescence. We investigated the effect of a structured, comprehensive, multidisciplinary, personalized, lifestyle intervention program of healthy diet and physical exercise on LTL in 508 children and adolescents (239 males, 269 females; 282 prepubertal, 226 pubertal), aged 10.14 ± 0.13 years. Participants were classified as obese (n = 267, 52.6%), overweight (n = 174, 34.2%), or of normal BMI (n = 67, 13.2%) according to the International Obesity Task Force (IOTF) cutoff points and were studied prospectively for one year. We demonstrated that LTL increased significantly after 1 year of the lifestyle interventions, irrespective of gender, pubertal status, or body mass index (BMI). Waist circumference was the best negative predictor of LTL at initial assessment. The implementation of the lifestyle interventions also resulted in a significant improvement in clinical (BMI, BMI z-score and waist to height ratio) and body composition indices of obesity, inflammatory markers, hepatic enzymes, glycated hemoglobin (HbA1C), quantitative insulin sensitivity check index (QUICKI), and lipid profile in all participants. These findings indicate that the increased LTL may be associated with a more favorable metabolic profile and decreased morbidity later in life.


Assuntos
Envelhecimento/genética , Leucócitos/patologia , Obesidade Infantil/genética , Telômero/patologia , Programas de Redução de Peso/métodos , Adolescente , Terapia Comportamental/métodos , Composição Corporal , Índice de Massa Corporal , Criança , Exercício Físico/fisiologia , Feminino , Humanos , Estilo de Vida , Masculino , Obesidade Infantil/sangue , Obesidade Infantil/terapia , Avaliação de Programas e Projetos de Saúde , Estudos Prospectivos , Resultado do Tratamento , Circunferência da Cintura
6.
Conserv Biol ; 34(3): 721-732, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31702070

RESUMO

Conservation biology was founded on the idea that efforts to save nature depend on a scientific understanding of how it works. It sought to apply ecological principles to conservation problems. We investigated whether the relationship between these fields has changed over time through machine reading the full texts of 32,000 research articles published in 16 ecology and conservation biology journals. We examined changes in research topics in both fields and how the fields have evolved from 2000 to 2014. As conservation biology matured, its focus shifted from ecology to social and political aspects of conservation. The 2 fields diverged and now occupy distinct niches in modern science. We hypothesize this pattern resulted from increasing recognition that social, economic, and political factors are critical for successful conservation and possibly from rising skepticism about the relevance of contemporary ecological theory to practical conservation.


Relaciones entre la Biología de la Conservación y la Ecología Mostradas a través de la Lectura Mediante Máquina de 32,000 Artículos Resumen La biología de la conservación se fundó a partir de la idea de que los esfuerzos para salvar a la naturaleza dependen del entendimiento científico de cómo funciona. La biología de la conservación buscaba aplicar los principios ecológicos a los problemas de conservación. En este trabajo investigamos si la relación entre estos ámbitos ha cambiado con el tiempo al realizar una lectura mediante máquina de 32,000 textos completos de artículos de investigación publicados en 16 revistas sobre ecología y biología de la conservación. También examinamos los cambios en los temas de investigación en ambos ámbitos y cómo éstos han evolucionado desde el año 2000 hasta el 2014. Conforme ha madurado la biología de la conservación, su enfoque se ha movido de los aspectos ecológicos de la conservación a los aspectos políticos y sociales. La ecología y la biología de la conservación se han separado y ahora ocupan nichos distintos dentro de la ciencia moderna. Nuestra hipótesis considera que este patrón resultó de incrementar el reconocimiento de que los factores sociales, económicos y políticos son muy importantes para una conservación exitosa. Posiblemente el patrón también proviene del creciente escepticismo acerca de la relevancia que la teoría ecológica contemporánea tiene para la conservación en práctica.


Assuntos
Conservação dos Recursos Naturais , Ecologia
7.
J Affect Disord ; 97(1-3): 187-95, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16844229

RESUMO

INTRODUCTION: Although a great number of depressive scales were developed during the last decades, there are only a few studies that compare them in terms of reliability and validity. The current study aimed to compare the properties of some of the most popular of these scales. MATERIALS AND METHODS: The study sample included 40 depressed patients 29.65+/-9.38 years old, and 120 normal comparison subjects 27.23+/-10.62 years old. The clinical diagnosis was reached by consensus of two examiners with the use of the SCAN v.2.0. The scales compared were the CES-D, ZDRS, BDI-I, and the KSQ. The STAI, the Life Change Scale (Holms and Rahe), and the EPQ were also administered. The analysis included the comparison of psychometric properties and the use of Pearson correlation coefficient and factor analysis. RESULTS: The results suggested that no scale was clearly superior to the others. All scales correlated to anxiety measurements, sociodemographic variables, personality dimensions and non-specific indices. The results reported here include an appendix with algorithms that help transforming one scale score into other scales scores. These algorithms can be useful for comparison purposes in meta-analytic studies. DISCUSSION: The comparison of several depressive scales provided no impressive results on the superiority or inferiority of a specific scale in comparison to the others.


Assuntos
Transtornos de Ansiedade/diagnóstico , Caráter , Transtorno Depressivo/diagnóstico , Acontecimentos que Mudam a Vida , Inventário de Personalidade/estatística & dados numéricos , Adolescente , Adulto , Algoritmos , Transtornos de Ansiedade/psicologia , Transtorno Depressivo/psicologia , Feminino , Grécia , Humanos , Masculino , Pessoa de Meia-Idade , Psicometria/estatística & dados numéricos , Reprodutibilidade dos Testes , Estatística como Assunto
8.
Ann Gen Psychiatry ; 5: 2, 2006 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-16448554

RESUMO

BACKGROUND: The State-Trait Anxiety Inventory form Y is a brief self-rating scale for the assessment of state and trait anxiety. The aim of the current preliminary study was to assess the psychometric properties of its Greek translation. MATERIALS AND METHODS: 121 healthy volunteers 27.22 +/- 10.61 years old, and 22 depressed patients 29.48 +/- 9.28 years old entered the study. In 20 of them the instrument was re-applied 1-2 days later. Translation and Back Translation was made. The clinical diagnosis was reached with the SCAN v.2.0 and the IPDE. The Symptoms Rating Scale for Depression and Anxiety (SRSDA) and the EPQ were applied for cross-validation purposes. The Statistical Analysis included the Pearson Correlation Coefficient and the calculation of Cronbach's alpha. RESULTS: The State score for healthy subjects was 34.30 +/- 10.79 and the Trait score was 36.07 +/- 10.47. The respected scores for the depressed patients were 56.22 +/- 8.86 and 53.83 +/- 10.87. Both State and Trait scores followed the normal distribution in control subjects. Cronbach's alpha was 0.93 for the State and 0.92 for the Trait subscale. The Pearson Correlation Coefficient between State and Trait subscales was 0.79. Both subscales correlated fairly with the anxiety subscale of the SRSDA. Test-retest reliability was excellent, with Pearson coefficient being between 0.75 and 0.98 for individual items and equal to 0.96 for State and 0.98 for Trait. CONCLUSION: The current study provided preliminary evidence concerning the reliability and the validity of the Greek translation of the STAI-form Y. Its properties are generally similar to those reported in the international literature, but further research is necessary.

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