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1.
PLoS One ; 16(4): e0249519, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33798222

RESUMO

Emotional bookkeeping is the process by which primates integrate the emotional effects of social interactions to form internal representations of their affiliative relationships. The dynamics and speed of this process, which comprises the formation, maintenance and fading out of affiliative relationships, are not clear. Empirical data suggest that affiliative relationships are slowly formed and do not easily fade out. The EMO-model, an agent-based model designed to simulate the social life of primates capable of emotional bookkeeping, was used to explore the effects of different types of internal relationship dynamics and speeds of increase and decrease of relationship strength. In the original EMO-model the internal dynamics involves a fast built-up of a relationship independent of its current quality, alongside a relatively fast fading out of relationship quality. Here we explore the effect of this original dynamics and an alternative dynamics more in line with empirical data, in combination with different speeds of internal relationship quality increase and decrease, on the differentiation and stability of affiliative relationships. The alternative dynamics leads to more differentiated and stable affiliative relationships than the original dynamics, especially when the speed with which internal relationship quality increases is low and the speed with which it decreases is intermediate. Consequently, individuals can groom different group members with varying frequency and support a rich social life with stable preferred partners and attention to several others. In conclusion, differentiated and stable affiliative relationships are especially formed when friends are not made too quickly and not forgotten too easily.


Assuntos
Emoções/fisiologia , Modelos Psicológicos , Comportamento Social , Predomínio Social , Animais , Asseio Animal , Macaca mulatta
2.
Am J Primatol ; 81(6): e22996, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31192494

RESUMO

Housing primates in naturalistic groups provides social benefits relative to solitary housing. However, food intake may vary across individuals, possibly resulting in overweight and underweight individuals. Information on relative adiposity (the amount of fat tissue relative to body weight) is needed to monitor overweight and underweight of group-housed individuals. However, the upper and lower relative adiposity boundaries are currently only known for macaques living solitarily in small cages. We determined the best measure of relative adiposity and explored the boundaries of overweight and underweight to investigate their incidence in group-housed adult male and female rhesus macaques and long-tailed macaques living in spacious enclosures at the Biomedical Primate Research Centre (BPRC), the Netherlands. During yearly health checks different relative adiposity measures were obtained. For long-tailed macaques, comparable data on founder and wild animals were also available. Weight-for-height indices (WHI) with height to the power of 3.0 (WHI3.0) for rhesus macaques and 2.7 (WHI2.7) for long-tailed macaques were optimally independent of height and were highly correlated with other relative adiposity measures. The boundary for overweight was similar in group-housed and solitary-housed macaques. A lower boundary for underweight, based on 2% body fat similar to wild primates, gave a better estimate for underweight in group-housed macaques. We propose that for captive group-housed rhesus macaques relative adiposity should range between 42 and 67 (WHI3.0) and for long-tailed macaques between 39 and 62 (WHI2.7). The majority of group-housed macaques in this facility have a normal relative adiposity, a considerable proportion (17-23%) is overweight, and a few (0-3%) are underweight.


Assuntos
Macaca fascicularis/anatomia & histologia , Macaca mulatta/anatomia & histologia , Sobrepeso/veterinária , Magreza/veterinária , Animais , Feminino , Abrigo para Animais , Masculino , Sobrepeso/epidemiologia , Prevalência , Magreza/epidemiologia
3.
J Pediatr Gastroenterol Nutr ; 69(3): 310-316, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31124888

RESUMO

OBJECTIVE: Paediatric-onset inflammatory bowel disease (IBD) is different from adult-onset IBD with respect to disease severity and its effect on growth and development. Care of paediatric IBD patients in some countries is dispersed among paediatricians and adult care providers, which may result in different outcomes. This study aims to assess the effect of care setting (paediatric vs adult-oriented) on health care utilization in adolescent IBD patients. METHODS: This is a Dutch population-based cohort study based on an insurance claims database covering 4.2 million insurees (approximately 25% of the Dutch population). We identified IBD patients ages 16 to 18 years and followed them until the age of 19 years or transfer to adult care, whichever came first. We categorized patients according to care setting: paediatric versus adult-oriented. We defined outcomes as corticosteroid use, IBD-related hospital admission, IBD-related surgery, and biological use. We estimated Cox proportional hazards regression models to control for confounding by indication. RESULTS: Among 626 patients, 380 (61%) were in paediatric and 246 (39%) in adult-oriented care. In paediatric care, patients were less likely to be treated with corticosteroids (hazard ratio [HR] 0.72, 95% confidence interval [CI] 0.52-0.99) or biologicals (HR 0.57, 95% CI 0.34-0.97), and had fewer IBD-related hospital admissions (HR 0.58, 95% CI 0.37-0.92). CONCLUSION: In a large and representative community cohort of adolescents with IBD, treatment in paediatric care setting was associated with significantly lower steroid and biological use, without increase in hospital admissions. These results might be used to optimize clinical care for adolescents with IBD.


Assuntos
Serviços de Saúde do Adolescente/estatística & dados numéricos , Doenças Inflamatórias Intestinais/epidemiologia , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Adolescente , Adulto , Estudos de Coortes , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Revisão da Utilização de Seguros , Masculino , Países Baixos/epidemiologia , Modelos de Riscos Proporcionais , Transição para Assistência do Adulto/estatística & dados numéricos , Adulto Jovem
4.
PeerJ ; 4: e1488, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26839737

RESUMO

Whether and how primates are able to maintain long-term affiliative relationships is still under debate. Emotional bookkeeping (EB), the partner-specific accumulation of emotional responses to earlier interactions, is a candidate mechanism that does not require high cognitive abilities. EB is difficult to study in real animals, due to the complexity of primate social life. Therefore, we developed an agent-based model based on macaque behavior, the EMO-model, that implements arousal and two emotional dimensions, anxiety-FEAR and satisfaction-LIKE, which regulate social behavior. To implement EB, model individuals assign dynamic LIKE attitudes towards their group members, integrating partner-specific emotional responses to earlier received grooming episodes. Two key parameters in the model were varied to explore their effects on long-term affiliative relationships: (1) the timeframe over which earlier affiliation is accumulated into the LIKE attitudes; and (2) the degree of partner selectivity. EB over short and long timeframes gave rise to low variation in LIKE attitudes, and grooming partner preferences were only maintained over one to two months. Only EB over intermediate-term timeframes resulted in enough variation in LIKE attitudes, which, in combination with high partner selectivity, enables individuals to differentiate between regular and incidental grooming partners. These specific settings resulted in a strong feedback between differentiated LIKE attitudes and the distribution of grooming, giving rise to strongly reciprocated partner preferences that could be maintained for longer periods, occasionally up to one or two years. Moreover, at these settings the individual's internal, socio-emotional memory of earlier affiliative episodes (LIKE attitudes) corresponded best to observable behavior (grooming partner preferences). In sum, our model suggests that intermediate-term LIKE dynamics and high partner selectivity seem most plausible for primates relying on emotional bookkeeping to maintain their social bonds.

5.
PLoS One ; 10(8): e0133978, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26309101

RESUMO

A dominance hierarchy is an important feature of the social organisation of group living animals. Although formal and/or agonistic dominance has been found in captive wolves and free-ranging dogs, applicability of the dominance concept in domestic dogs is highly debated, and quantitative data are scarce. Therefore, we investigated 7 body postures and 24 behaviours in a group of domestic dogs for their suitability as formal status indicators. The results showed that high posture, displayed in most dyadic relationships, and muzzle bite, displayed exclusively by the highest ranking dogs, qualified best as formal dominance indicators. The best formal submission indicator was body tail wag, covering most relationships, and two low postures, covering two-thirds of the relationships. In addition, both mouth lick, as included in Schenkel's active submission, and pass under head qualified as formal submission indicators but were shown almost exclusively towards the highest ranking dogs. Furthermore, a status assessment based on changes in posture displays, i.e., lowering of posture (LoP) into half-low, low, low-on-back or on-back, was the best status indicator for most relationships as it showed good coverage (91% of the dyads), a nearly linear hierarchy (h' = 0.94, p<0.003) and strong unidirectionality (DCI = 0.97). The associated steepness of 0.79 (p<0.0001) indicated a tolerant dominance style for this dog group. No significant correlations of rank with age or weight were found. Strong co-variation between LoP, high posture, and body tail wag justified the use of dominance as an intervening variable. Our results are in line with previous findings for captive wolves and free-ranging dogs, for formal dominance with strong linearity based on submission but not aggression. They indicate that the ethogram for dogs is best redefined by distinguishing body postures from behavioural activities. A good insight into dominance hierarchies and its indicators will be helpful in properly interpreting dog-dog relationships and diagnosing problem behaviour in dogs.


Assuntos
Comportamento Animal , Predomínio Social , Agressão , Análise de Variância , Animais , Cães , Feminino , Masculino , Postura
6.
Eur Heart J ; 36(24): 1519-28, 2015 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-25888007

RESUMO

AIMS: To assess the effects of multi-disciplinary cardiac rehabilitation (CR) on survival in the full population of patients with an acute coronary syndrome (ACS) and patients that underwent coronary revascularization and/or heart valve surgery. METHODS AND RESULTS: Population-based cohort study in the Netherlands using insurance claims database covering ∼22% of the Dutch population (3.3 million persons). All patients with an ACS with or without ST elevation, and patients who underwent coronary revascularization and/or valve surgery in the period 2007-10 were included. Patients were categorized as having received CR when an insurance claim for CR was made within the first 180 days after the cardiac event or revascularization. The primary outcome was survival time from the inclusion date, limited to a total follow-up period of 4 years, with a minimum of 180 days. Propensity score weighting was used to control for confounding by indication. Among 35 919 patients with an ACS and/or coronary revascularization or valve surgery, 11 014 (30.7%) received CR. After propensity score weighting, the adjusted hazard ratio (HR) associated with receiving CR was 0.65 (95% CI 0.56-0.77). The largest benefit was observed for patients who underwent coronary artery bypass grafting (CABG) and/or valve surgery (HR = 0.55, 95% CI 0.42-0.74). CONCLUSION: In a large and representative community cohort of Dutch patients with an ACS and/or intervention, CR was associated with a substantial survival benefit up to 4 years. This survival benefit was present regardless of age, type of diagnosis, and type of intervention.


Assuntos
Síndrome Coronariana Aguda/reabilitação , Implante de Prótese de Valva Cardíaca/reabilitação , Síndrome Coronariana Aguda/mortalidade , Síndrome Coronariana Aguda/cirurgia , Idoso , Estudos de Coortes , Fatores de Confusão Epidemiológicos , Feminino , Implante de Prótese de Valva Cardíaca/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Revascularização Miocárdica/reabilitação , Países Baixos/epidemiologia , Análise de Sobrevida , Resultado do Tratamento
7.
PLoS One ; 10(3): e0118921, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25785601

RESUMO

Primate affiliative relationships are differentiated, individual-specific and often reciprocal. However, the required cognitive abilities are still under debate. Recently, we introduced the EMO-model, in which two emotional dimensions regulate social behaviour: anxiety-FEAR and satisfaction-LIKE. Emotional bookkeeping is modelled by providing each individual with partner-specific LIKE attitudes in which the emotional experiences of earlier affiliations with others are accumulated. Individuals also possess fixed partner-specific FEAR attitudes, reflecting the stable dominance hierarchy. In this paper, we focus on one key parameter of the model, namely the degree of partner selectivity, i.e. the extent to which individuals rely on their LIKE attitudes when choosing affiliation partners. Studying the effect of partner selectivity on the emergent affiliative relationships, we found that at high selectivity, individuals restricted their affiliative behaviours more to similar-ranking individuals and that reciprocity of affiliation was enhanced. We compared the emotional bookkeeping model with a control model, in which individuals had fixed LIKE attitudes simply based on the (fixed) rank-distance, instead of dynamic LIKE attitudes based on earlier events. Results from the control model were very similar to the emotional bookkeeping model: high selectivity resulted in preference of similar-ranking partners and enhanced reciprocity. However, only in the emotional bookkeeping model did high selectivity result in the emergence of reciprocal affiliative relationships that were highly partner-specific. Moreover, in the emotional bookkeeping model, LIKE attitude predicted affiliative behaviour better than rank-distance, especially at high selectivity. Our model suggests that emotional bookkeeping is a likely candidate mechanism to underlie partner-specific reciprocal affiliation.


Assuntos
Comportamento de Escolha , Emoções , Modelos Psicológicos , Primatas/psicologia , Comportamento Social , Agressão/psicologia , Animais , Ansiedade/psicologia , Atitude , Medo/psicologia , Asseio Animal
8.
Primates ; 56(1): 21-7, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25238793

RESUMO

Hundreds of rehabilitant great apes have been released into the wild, and thousands await release. However, survival rates after release can be as low as 20%. Several factors influence individuals' survival rates, one of which is the capacity to obtain an adequate diet once released. Released individuals are faced with a mixture of familiar and novel foods in an unfamiliar forest; therefore, it is important to understand how they increase acceptance and consumption of novel foods. This is especially vital for omnivorous species, such as wild great apes, which consume several hundred species of different foods. We assessed the effects of repeated exposures and sociality (i.e. co-feeding in the presence of one or more other individuals) on the acceptance and consumption of novel foods by captive orangutans (Pongo sp). Repeated exposures of food (novel, at first) did not cause an increase of acceptance of food; in other words, the orangutans did not start to eat a food item after being exposed to that food more often, but repeated exposures of food increased consumption (i.e. quantity). After repeated exposures, the orangutans also became gradually more familiar with the food, decreasing their explorative behaviour. The presence of co-feeding conspecifics resulted in an increased acceptance of the novel food by orangutans, and they ate a larger amount of said foods than when alone. Repeated exposure and sociality may benefit rehabilitant great apes in augmenting and diversifying diet and, once practiced before release, may accelerate an individuals' adaptation to their new habitat, improving survival chances. Great ape rescue, rehabilitation and reintroduction require large financial and logistic investments; however, their effectiveness may be improved at low cost and low effort through the suggested measures.


Assuntos
Comportamento Alimentar , Pongo/fisiologia , Comportamento Social , Animais , Feminino , Masculino
9.
PLoS One ; 9(2): e87955, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24504194

RESUMO

Agent-based models provide a promising tool to investigate the relationship between individuals' behavior and emerging group-level patterns. An individual's behavior may be regulated by its emotional state and its interaction history with specific individuals. Emotional bookkeeping is a candidate mechanism to keep track of received benefits from specific individuals without requiring high cognitive abilities. However, how this mechanism may work is difficult to study in real animals, due to the complexity of primate social life. To explore this theoretically, we introduce an agent-based model, dubbed EMO-model, in which we implemented emotional bookkeeping. In this model the social behaviors of primate-like individuals are regulated by emotional processes along two dimensions. An individual's emotional state is described by an aversive and a pleasant dimension (anxiety and satisfaction) and by its activating quality (arousal). Social behaviors affect the individuals' emotional state. To implement emotional bookkeeping, the receiver of grooming assigns an accumulated affiliative attitude (LIKE) to the groomer. Fixed partner-specific agonistic attitudes (FEAR) reflect the stable dominance relations between group members. While the emotional state affects an individual's general probability of executing certain behaviors, LIKE and FEAR affect the individual's partner-specific behavioral probabilities. In this way, emotional processes regulate both spontaneous behaviors and appropriate responses to received behaviors, while emotional bookkeeping via LIKE attitudes regulates the development and maintenance of affiliative relations. Using an array of empirical data, the model processes were substantiated and the emerging model patterns were partially validated. The EMO-model offers a framework to investigate the emotional bookkeeping hypothesis theoretically and pinpoints gaps that need to be investigated empirically.


Assuntos
Ansiedade , Atitude , Emoções , Modelos Psicológicos , Comportamento Social , Animais , Primatas , Reprodutibilidade dos Testes
10.
J Acoust Soc Am ; 134(3): 2326-35, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23967963

RESUMO

One of the most apparent discontinuities between non-human primate (primate) call communication and human speech concerns repertoire size. The former is essentially fixed to a limited number of innate calls, while the latter essentially consists of numerous learned components. Consequently, primates are thought to lack laryngeal control required to produce learned voiced calls. However, whether they may produce learned voiceless calls awaits investigation. Here, a case of voiceless call learning in primates is investigated--orangutan (Pongo spp.) whistling. In this study, all known whistling orangutans are inventoried, whistling-matching tests (previously conducted with one individual) are replicated with another individual using original test paradigms, and articulatory and acoustic whistle characteristics are compared between three orangutans. Results show that whistling has been reported for ten captive orangutans. The test orangutan correctly matched human whistles with significantly high levels of performance. Whistle variation between individuals indicated voluntary control over the upper lip, lower lip, and respiratory musculature, allowing individuals to produce learned voiceless calls. Results are consistent with inter- and intra-specific social transmission in whistling orangutans. Voiceless call learning in orangutans implies that some important components of human speech learning and control were in place before the homininae-ponginae evolutionary split.


Assuntos
Comportamento Imitativo , Aprendizagem , Pongo/fisiologia , Canto , Vocalização Animal , Acústica , Animais , Evolução Biológica , Fenômenos Biomecânicos , Feminino , Humanos , Lábio/anatomia & histologia , Lábio/fisiologia , Masculino , Pongo/anatomia & histologia , Pongo/psicologia , Músculos Respiratórios/anatomia & histologia , Músculos Respiratórios/fisiologia , Espectrografia do Som , Especificidade da Espécie
11.
Eur J Prev Cardiol ; 20(2): 349-56, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22345699

RESUMO

AIMS: Despite its documented efficacy, cardiac rehabilitation (CR) is still not well implemented in current clinical practice. The aims of the present study were to assess CR uptake rates in the Netherlands, and to identify factors that determine uptake. METHODS: The cohort consisted of persons insured with Achmea Zorg en Gezondheid. Based on insurance claims, we assessed CR uptake rates in 2007 among patients with an acute coronary syndrome (ACS), patients who underwent coronary artery bypass graft surgery, percutaneous coronary intervention (PCI), or valvular surgery, and patients with stable angina pectoris (AP) or chronic heart failure (CHF). In addition, we evaluated the relation between CR uptake and demographic, disease-related, and geographic factors for patients with an ACS and/or intervention. RESULTS: The CR uptake rate in the entire cohort (n = 35,752) was 11.7%. The uptake rate among patients with an ACS and/or intervention (n = 12,201) was 28.5%, as opposed to 3.0% among patients with CHF or stable AP (n = 23,551). The highest CR uptake rate was observed in patients who underwent cardiac surgery (58.7%). Factors associated with lower CR uptake were female gender, older age, elective PCI (as compared to acute PCI), unstable AP (as compared to myocardial infarction), larger distance to the nearest provider of CR, and comorbidity. CONCLUSION: A minority of Dutch patients eligible for CR received CR. Future implementation strategies should focus on females, elderly patients, patients with unstable AP and/or after elective PCI, patients with long travelling distances to the nearest CR provider, and patients with comorbidities.


Assuntos
Acessibilidade aos Serviços de Saúde , Cardiopatias/reabilitação , Padrões de Prática Médica , Síndrome Coronariana Aguda/epidemiologia , Síndrome Coronariana Aguda/reabilitação , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Angina Estável/epidemiologia , Angina Estável/reabilitação , Angina Instável/epidemiologia , Angina Instável/reabilitação , Doença Crônica , Comorbidade , Ponte de Artéria Coronária , Feminino , Fidelidade a Diretrizes , Cardiopatias/diagnóstico , Cardiopatias/epidemiologia , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/reabilitação , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Países Baixos/epidemiologia , Razão de Chances , Intervenção Coronária Percutânea , Guias de Prática Clínica como Assunto , Prognóstico , Características de Residência , Fatores de Risco , Fatores Sexuais
12.
Behav Ecol Sociobiol ; 66(6): 931-945, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22661823

RESUMO

Next to predator detection, primate vigilance also serves to keep track of relevant conspecifics. The degree of vigilance towards group members often reflects the dominance rank of an individual: subordinates pay attention to dominants. Although it has been suggested that subordinates' vigilance may result in spatial centrality of dominants, this has not been addressed in either empirical or modeling studies. Using agent-based models, we determined how social vigilance affects socio-spatial properties of primate groups. A basic model without social vigilance, where individuals avoid potential aggressors (avoidance model), was contrasted with two models that each additionally included a different type of social vigilance: a) monitoring a specific potential aggressor to remain informed on its whereabouts (monitoring model) or b) scanning the whole group to detect potential aggressors (scanning model). Adding monitoring or scanning behavior to the avoidance model reinforced spatial centrality of dominants, a pattern often observed in primates, and resulted in more spread out groups. Moreover, variation in scanning tendency alone was already sufficient to generate spatial centrality of dominants: frequently scanning subordinates could move further away from the group center than dominants, before losing sight of group members. In the monitoring model, two mechanisms caused decreased encounter frequencies among subordinates: a) increased inter-individual distances, and b) frequent monitoring of central dominants. In the scanning model, encounters among subordinates decreased due to increased inter-individual distances. This agent-based model study provides a clear indication that individual variation in social vigilance may be an important structuring feature of primate social groups.

13.
Int J Primatol ; 33(2): 287-304, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22467998

RESUMO

Meat-eating is an important aspect of human evolution, but how meat became a substantial component of the human diet is still poorly understood. Meat-eating in our closest relatives, the great apes, may provide insight into the emergence of this trait, but most existing data are for chimpanzees. We report 3 rare cases of meat-eating of slow lorises, Nycticebus coucang, by 1 Sumatran orangutan mother-infant dyad in Ketambe, Indonesia, to examine how orangutans find slow lorises and share meat. We combine these 3 cases with 2 previous ones to test the hypothesis that slow loris captures by orangutans are seasonal and dependent on fruit availability. We also provide the first (to our knowledge) quantitative data and high-definition video recordings of meat chewing rates by great apes, which we use to estimate the minimum time necessary for a female Australopithecus africanus to reach its daily energy requirements when feeding partially on raw meat. Captures seemed to be opportunistic but orangutans may have used olfactory cues to detect the prey. The mother often rejected meat sharing requests and only the infant initiated meat sharing. Slow loris captures occurred only during low ripe fruit availability, suggesting that meat may represent a filler fallback food for orangutans. Orangutans ate meat more than twice as slowly as chimpanzees (Pan troglodytes), suggesting that group living may function as a meat intake accelerator in hominoids. Using orangutan data as a model, time spent chewing per day would not require an excessive amount of time for our social ancestors (australopithecines and hominids), as long as meat represented no more than a quarter of their diet. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s10764-011-9574-z) contains supplementary material, which is available to authorized users.

14.
PLoS One ; 6(11): e26189, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22125595

RESUMO

In group-living animals, such as primates, the average spatial group structure often reflects the dominance hierarchy, with central dominants and peripheral subordinates. This central-peripheral group structure can arise by self-organization as a result of subordinates fleeing from dominants after losing a fight. However, in real primates, subordinates often avoid interactions with potentially aggressive group members, thereby preventing aggression and subsequent fleeing. Using agent-based modeling, we investigated which spatial and encounter structures emerge when subordinates also avoid known potential aggressors at a distance as compared with the model which only included fleeing after losing a fight (fleeing model). A central-peripheral group structure emerged in most conditions. When avoidance was employed at small or intermediate distances, centrality of dominants emerged similar to the fleeing model, but in a more pronounced way. This result was also found when fleeing after a fight was made independent of dominance rank, i.e. occurred randomly. Employing avoidance at larger distances yielded more spread out groups. This provides a possible explanation of larger group spread in more aggressive species. With avoidance at very large distances, spatially and socially distinct subgroups emerged. We also investigated how encounters were distributed amongst group members. In the fleeing model all individuals encountered all group members equally often, whereas in the avoidance model encounters occurred mostly among similar-ranking individuals. Finally, we also identified a very general and simple mechanism causing a central-peripheral group structure: when individuals merely differed in velocity, faster individuals automatically ended up at the periphery. In summary, a central-peripheral group pattern can easily emerge from individual variation in different movement properties in general, such as fleeing, avoidance or velocity. Moreover, avoidance behavior also affects the encounter structure and can lead to subgroup formation.


Assuntos
Modelos Biológicos , Primatas/fisiologia , Comportamento Social , Predomínio Social , Agressão , Algoritmos , Animais , Simulação por Computador , Dinâmica Populacional , Primatas/psicologia
15.
PLoS One ; 6(2): e16593, 2011 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-21359204

RESUMO

Recollecting the what-where-when of an episode, or episodic-like memory, has been established in corvids and rodents. In humans, a linkage between remembering the past and imagining the future has been recognised. While chimpanzees can plan for the future, their episodic-like memory has hardly been investigated. We tested chimpanzees (Pan troglodytes) with an adapted food-catching paradigm. They observed the baiting of two locations amongst four and chose one after a given delay (15 min, 1 h or 5 h). We used two combinations of food types, a preferred and a less preferred food that disappeared at different rates. The subjects had to base their choices on the time elapsed since baiting, and on their memory of which food was where. They could recover either their preferred food or the one that remained present. All animals failed to obtain the preferred or present foods above chance levels. They were like-wise unsuccessful at choosing baited cups above chance levels. The subjects, thus, failed to use any feature of the baiting events to guide their choices. Nonetheless, their choices were not random, but the result of a developed location-based association strategy. Choices in the second half of the study correlated with the rewards obtained at each location in the first half of the study, independent from the choices made for each location in the first half of the study. This simple location-based strategy yielded a fair amount of food. The animals' failure to remember the what-where-when in the presented set-up may be due to the complexity of the task, rather than an inability to form episodic-like memories, as they even failed to remember what was where after 15 minutes.


Assuntos
Aprendizagem por Associação/fisiologia , Memória/fisiologia , Pan troglodytes/fisiologia , Recompensa , Percepção Espacial/fisiologia , Animais , Comportamento de Escolha/fisiologia , Comportamento Alimentar/fisiologia , Comportamento Alimentar/psicologia , Feminino , Preferências Alimentares , Gestos , Masculino , Modelos Biológicos , Pan troglodytes/psicologia , Reforço Psicológico , Análise e Desempenho de Tarefas
16.
Rand Health Q ; 1(1): 13, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-28083169

RESUMO

Tobacco use is one of the largest avoidable causes of morbidity and premature death in the EU. Whilst smoking prevalence in the EU has been declining over the past 30 years, smoking has remained more prevalent among men than women in the EU-27, with some of the new Member States reporting the widest gaps between male and female smokers. For young smokers (13 to 15 years old) this situation is somewhat reversed, with slightly more girls than boys smoking. Against this background, the European Commission Directorate-General for Health and Consumer Protection (DG SANCO) considered a revision of the Tobacco Products Directive 2001/37/EC across five general areas: scope of the directive, labelling requirements, registration and market control fees, ingredients, and sales arrangements. More specifically, the types of policy options under consideration included (but were not limited to): an increase of warning label sizes on the back of packaging to 100%, a restriction for the display of products at retail outlets and an introduction of additional measurement method for TNCO (the modified ISO method) with maximum limits set accordingly. DG SANCO commissioned RAND Europe to provide support in assessing the potential health, macroeconomic, and compliance cost and administrative burden impacts of revising the Tobacco Products Directive. In addition to assessing impacts, the study provides an up-to-date overview of the evidence and basis for current tobacco product regulation that may be of interest to a wider audience interested in tobacco control policies.

17.
Psychiatry Res ; 176(2-3): 219-23, 2010 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-20219250

RESUMO

Previous studies that operationalized reactive aggression using behavioral observations in general populations have not taken into account the type of stimulus that elicits reactive aggression. In the present study we define a specific form of reactive aggression, i.e., reactive aggression in response to neutral behavior of a peer, which we will call unprovoked reactive aggression. We were specifically interested in children with severe aggressive behavior problems, since they may respond with reactive aggression even though the opponent did not clearly provoke them, but instead showed neutral behavior. Children with a disruptive behavior disorder (DBD) and normal control (NC) children participated in separate play sessions in which they played with a normal peer (NP). Children with DBD showed more unprovoked reactive aggression than NC children, during a cooperative game. Moreover, for children with DBD, unprovoked reactive aggressive behavior in this game correlated with parent-rated reactive aggression. Results of this study suggest that an unprovoked reactive form of aggression can be identified in children with DBD.


Assuntos
Agressão/fisiologia , Transtornos de Deficit da Atenção e do Comportamento Disruptivo/fisiopatologia , Transtornos de Deficit da Atenção e do Comportamento Disruptivo/psicologia , Grupo Associado , Análise de Variância , Lista de Checagem/métodos , Distribuição de Qui-Quadrado , Criança , Comportamento de Escolha/fisiologia , Comportamento Cooperativo , Humanos , Testes de Inteligência , Relações Interpessoais , Masculino , Observação/métodos , Relações Pais-Filho , Jogos e Brinquedos/psicologia , Técnicas Sociométricas
18.
Am J Manag Care ; 15(11): 842-5, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19895189

RESUMO

OBJECTIVE: To help health professionals understand and evaluate the concept of efficiency and its measurement in practice. STUDY DESIGN: We reviewed conceptual and practical analyses of healthcare efficiency and its measurement and describe our findings. METHODS: We searched the following 3 sources: the MEDLINE and EconLit databases for articles published from 1990 to 2008 using the keywords efficiency, inefficiency, productivity, and economic profiling; seminal economic studies of efficiency identified in MEDLINE or EconLit or in economics reference materials; and the "gray literature" on efficiency measures developed by private organizations. RESULTS: An essential element of efficiency is that healthcare outputs are as large as possible given their inputs. An efficiency measure specifies outputs and inputs appropriate to the goals of the assessment. Participants in the healthcare system have differing perspectives about the goals of efficiency assessments, relevant outputs and inputs, and validity of measures. CONCLUSION: The broad meaning and the value of healthcare efficiency seem uncontroversial, yet any particular application may be confronted with conflicting perspectives and with practical challenges.


Assuntos
Eficiência Organizacional , Pessoal de Saúde , Custos e Análise de Custo , Humanos , Qualidade da Assistência à Saúde
19.
Aggress Behav ; 35(5): 430-6, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19533684

RESUMO

Violence was shown to be qualitatively different from functional hyper-aggression in mice selected for high aggression namely Short Attack Latency (SAL), Turku Aggressive (TA) and North Carolina (NC900) strains. This study aimed at investigating whether this adulthood violent phenotype as seen previously in the SAL mice is fixed and hence behaviorally inflexible right from day 1 of the experiment or consequential, i.e., subject to gradual change from functional aggression to violence. The functionally hyper-aggressive strains namely TA and NC900 strains served as controls for the study. Methodologically, behavioral (in)flexibility was studied using the overall sequential structure of agonistic behavior. In particular, intra-individual variations in the overall agonistic behavior as well as offensive, pre- and post-offensive behavior transitions, directly related to the resident-intruder interactions were investigated. The SAL mice showed the least intra-individual variation in their overall sequential agonistic structure as well as a fixed offense-oriented agonistic behavior of highest magnitude when compared with the other strains. Additionally, the pre- and post- offensive transitions were most salient in the functionally hyper-aggressive TA and NC900 strains, whereas virtually absent in the SAL mice. Thus, the violent behavior of the adult SAL mice is behaviorally inflexible or fixed, whereas the functionally hyper-aggressive behavior of the adult TA and NC900 mice is behaviorally flexible and constantly adaptive to the opponent behavior, over 3 days of repeated resident-intruder interaction.


Assuntos
Comportamento Agonístico , Comportamento Animal , Genética Comportamental , Violência , Fatores Etários , Animais , Modelos Lineares , Masculino , Camundongos , Camundongos Endogâmicos , Fenótipo
20.
Genet Med ; 11(7): 510-7, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19478682

RESUMO

PURPOSE: The goal of this project was to assess genetic/genomic content in electronic health records. METHODS: Semistructured interviews were conducted with key informants. Questions addressed documentation, organization, display, decision support and security of family history and genetic test information, and challenges and opportunities relating to integrating genetic/genomics content in electronic health records. RESULTS: There were 56 participants: 10 electronic health record specialists, 18 primary care clinicians, 16 medical geneticists, and 12 genetic counselors. Few clinicians felt their electronic record met their current genetic/genomic medicine needs. Barriers to integration were mostly related to problems with family history data collection, documentation, and organization. Lack of demand for genetics content and privacy concerns were also mentioned as challenges. Data elements and functionality requirements that clinicians see include: pedigree drawing; clinical decision support for familial risk assessment and genetic testing indications; a patient portal for patient-entered data; and standards for data elements, terminology, structure, interoperability, and clinical decision support rules. Although most said that there is little impact of genetics/genomics on electronic records today, many stated genetics/genomics would be a driver of content in the next 5-10 years. CONCLUSIONS: Electronic health records have the potential to enable clinical integration of genetic/genomic medicine and improve delivery of personalized health care; however, structured and standardized data elements and functionality requirements are needed.


Assuntos
Privacidade Genética/normas , Genética Médica/métodos , Sistemas Computadorizados de Registros Médicos/organização & administração , Sistemas Computadorizados de Registros Médicos/normas , Atitude do Pessoal de Saúde , Entrevistas como Assunto , Sistemas Computadorizados de Registros Médicos/tendências , Padrões de Referência
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