Behavioural robustness and the distributed mechanisms hypothesis

A current challenge in neuroscience and systems biology is to better understand properties that allow organisms to exhibit and sustain appropriate behaviours despite the effects of perturbations (behavioural robustness). There are still significant theoretical difficulties in this endeavour, mainly due to the context-dependent nature of the problem. Biological robustness, in general, is considered in the literature as a property that emerges from the internal structure of organisms, rather than being a dynamical phenomenon involving agent-internal controls, the organism body, and the environment. Our hypothesis is that the capacity for behavioural robustness is rooted in dynamical processes that are distributed between agent ‘brain’, body, and environment, rather than warranted exclusively by organisms’ internal mechanisms. Distribution is operationally defined here based on perturbation analyses. Evolutionary Robotics (ER) techniques are used here to construct four computational models to study behavioural robustness from a systemic perspective. Dynamical systems theory provides the conceptual framework for these investigations. The first model evolves situated agents in a goalseeking scenario in the presence of neural noise perturbations. Results suggest that evolution implicitly selects neural systems that are noise-resistant during coupling behaviour by concentrating search in regions of the fitness landscape that retain functionality for goal approaching. The second model evolves situated, dynamically limited agents exhibiting minimalcognitive behaviour (categorization task). Results indicate a small but significant tendency toward better performance under most types of perturbations by agents showing further cognitivebehavioural dependency on their environments. The third model evolves experience-dependent robust behaviour in embodied, one-legged walking agents. Evidence suggests that robustness is rooted in both internal and external dynamics, but robust motion emerges always from the systemin-coupling. The fourth model implements a historically dependent, mobile-object tracking task under sensorimotor perturbations. Results indicate two different modes of distribution, one in which inner controls necessarily depend on a set of specific environmental factors to exhibit behaviour, then these controls will be more vulnerable to perturbations on that set, and another for which these factors are equally sufficient for behaviours. Vulnerability to perturbations depends on the particular distribution. In contrast to most existing approaches to the study of robustness, this thesis argues that behavioural robustness is better understood in the context of agent-environment dynamical couplings, not in terms of internal mechanisms. Such couplings, however, are not always the full determinants of robustness. Challenges and limitations of our approach are also identified for future studies

Functionally different PIN proteins control auxin flux during bulbil development in Agave tequilana

In Agave tequilana, reproductive failure or inadequate flower development stimulates the formation of vegetative bulbils at the bracteoles, ensuring survival in a hostile environment. Little is known about the signals that trigger this probably unique phenomenon in agave species. Here we report that auxin plays a central role in bulbil development and show that the localization of PIN1-related proteins is consistent with altered auxin transport during this process. Analysis of agave transcriptome data led to the identification of the A. tequilana orthologue of PIN1 (denoted AtqPIN1) and a second closely related gene from a distinct clade reported as ‘Sister of PIN1’ (denoted AtqSoPIN1). Quantitative real-time reverse transcription–PCR (RT-qPCR) analysis showed different patterns of expression for each gene during bulbil formation, and heterologous expression of the A. tequilana PIN1 and SoPIN1 genes in Arabidopsis thaliana confirmed functional differences between these genes. Although no free auxin was detected in induced pedicel samples, changes in the levels of auxin precursors were observed. Taken as a whole, the data support the model that AtqPIN1 and AtqSoPIN1 have co-ordinated but distinct functions in relation to auxin transport during the initial stages of bulbil formation

Mind over mood: exploring the executive function’s role in downregulation

Emotion regulation plays a key role in well adapted behaviour, however, factors influencing individual differences in ER are still under investigation. Across two studies we investigate the complex relationship between executive functions (EFs) and emotional downregulation through two complementary research designs. The focus lies on key components of EFs—working memory, inhibitory control, and switching—and their relationship with effective emotional regulation. Surprisingly, switching emerged as the sole significant predictor in two multiple linear regression models, challenging the conventional belief that all major EFs broadly contribute to emotional downregulation. The first study, involving 248 Ecuadorian adults between 18 and 60 years old, used experimental tasks to assess the association between EFs and emotional regulation, aligning with existing literature that posits a link between EFs and emotional control. The second study, involving 180 Ecuadorian adults between 18 and 43 years old, added depth by incorporating self-report measures, providing a broader, ecologically valid perspective. However, these measures did not significantly predict downregulation, highlighting a gap between self-perception and actual cognitive abilities. Additionally, demographic predictors varied between the two studies, urging future research to consider methodological design and task selection carefully. The study also raises questions about the validity of commonly used measures, emphasising the need for more nuanced tools to capture the complexity of EFs and emotional regulation. Our findings suggest a targeted research avenue focusing on EFs for both future research and clinical interventions. Attention is called to the methodological decisions that can influence the observed associations, and the need for broader demographic representation in future studies

Collective excitations in liquid D2 confined within the mesoscopic pores of a MCM-41 molecular sieve

We present a comparative study of the excitations in bulk and liquid D2 confined within the pores of MCM-41. The material (Mobile Crystalline Material-41) is a silicate obtained by means of a template that yields a partially crystalline structure composed by arrays of nonintersecting hexagonal channels of controlled width having walls made of amorphous SiO2. Its porosity was characterized by means of adsorption isotherms and found to be composed by a regular array of pores having a narrow distribution of sizes with a most probable value of 2.45 nm. The assessment of the precise location of the sample within the pores is carried out by means of pressure isotherms. The study was conducted at two pressures which correspond to pore fillings above the capillary condensation regime. Within the range of wave vectors where collective excitations can be followed up (0.3<Q<3.0 $\AA$&#8722;1), we found confinement brings forward a large shortening of the excitation lifetimes that shifts the characteristic frequencies to higher energies. In addition, the coherent quasielastic scattering shows signatures of reduced diffusivity.Comment: 6 page

Pattern of Activated Pathways and Quality of Collateral Status in Patients with Symptomatic Internal Carotid Artery Occlusion

Background: Internal carotid artery occlusion (ICAO) is an important risk factor for stroke. Cerebral hemodynamics in patients with ICAO depends on the individual capacity to activate sufficient collateral pathways. Therefore, the assessment of intracranial collaterals is essential for the acute and long-term management of these patients and accurate estimation of further stroke risk. Methods: Acute stroke patients with unilateral ICAO were prospectively enrolled. We assessed the following collaterals by transcranial color-coded sonography (TCCS): the anterior and posterior communicating artery (ACoA, PCoA), the ophthalmic artery (OA), and leptomeningeal collaterals of the posterior cerebral artery (LMC). We subdivided the flow pattern of the Doppler spectrum in the middle cerebral artery (MCA) into 3 categories: (1) good, (2) moderate, and (3) bad according to the hemodynamic effects on the ipsilateral MCA flow. Finally, we compared the individual TCCS results with the stroke pattern detected on CT or MRI scan. Results: One hundred thirteen patients (age 66 +/- 12 years; female 24) were included. The collateral status was good, moderate, and bad in 59 (52%), 37 (33%), and 17 (15%) patients, respectively. The ACoA collateral was most frequently activated (81%), followed by the OA (63%), the PCoA (53%), and the LMC (22%). The quality of the collateral status was determined by the type (p = 0.0003) but not by the number (p = 0.19) of activated collateral pathways. Good collateral function was highly associated with primary collaterals (ACoA > PCoA). Best parameter for a good collateral status was an antegrade flow in the OA, indicating a high blood supply via the communicating arteries. Conclusions: TCCS allows the assessment of intracranial collaterals and their hemodynamic capacity. Prevalence of collateral sufficiency in ICAO seems to be higher than previously reported. ACoA cross flow is essential for the optimal hemodynamic compensation of ICAO. Antegrade OA flow indicates good collateral status

Personality Disorders and Health Problems Distinguish Suicide Attempters from Completers in a Direct Comparison

Background Whether suicide attempters and completers represent the same population evaluated at different points along a progression towards suicide death, overlapping populations, or completely different populations is a problem still unresolved. Methods 446 Adult suicide attempters and knowledgeable collateral informants for 190 adult suicide probands were interviewed. Sociodemographic and clinical data was collected for both groups using semi-structured interviews and structured assessments. Univariate analyses and logistic regression models were conducted to explore the similarities and differences between suicide attempters and completers. Results Univariate analyses yielded significant differences in sociodemographics, recent life events, impulsivity, suicide intent, and distribution of Axis I and II disorders. A logistic regression model aimed at distinguishing suicide completers from attempters properly classified 90% of subjects. The most significant variables that distinguished suicide from attempted suicide were the presence of narcissistic personality disorder (OR=21.4; 95% CI=6.8–67.7), health problems (OR=20.6; 95% CI=5.6–75.9), male sex (OR=9.6; 95% CI=4.42–20.9), and alcohol abuse (OR=5.5; 95% CI=2.3–14.2). Limitations Our study shares the limitations of studies comparing suicide attempters and completers, namely that information from attempters can be obtained from the subject himself, whereas the assessment of completers depends on information from close family or friends. Furthermore, different semi-structured instruments assessed Axis I and Axis II disorders in suicide attempters and completers. Finally, we have no data on inter-rater reliability data. Conclusions Suicide completers are more likely to be male and suffer from alcohol abuse, health problems (e.g. somatic illness), and narcissistic personality disorder. The findings emphasize the importance of implementing suicide prevention programs tailored to suicide attempters and completers

Low transmission risk of African swine fever virus between wild boar infected by an attenuated isolate and susceptible domestic pigs

African swine fever (ASF) is a lethal infectious disease that affects domestic and wild pigs. This complex virus has already affected five continents and more than 70 countries and is considered to be the main threat to the global swine industry. The disease can potentially be transmitted directly through contact with infectious animals, or indirectly by means of contaminated feed or environments. Nevertheless, the knowledge regarding the transmission patterns of different ASF virus isolates at the wildlife-livestock interface is still limited. We have, therefore, assessed the potential transmission of an attenuated ASF virus isolate between infectious wild boar and directly exposed domestic pig. We registered 3,369 interspecific interactions between animals, which were brief and mostly initiated by wild boar. The major patterns observed during the study were head-to-head contact owing to sniffing, thus suggesting a high probability of pathogen transmission. However, only one of the five domestic pigs had a short period of viremia and became serologically positive for ASF virus antibodies. It was additionally discovered that the wild boar did not transmit the virulent virus isolate to the domestic pigs, which suggests that the presence of attenuated ASF virus isolates in affected areas may control the spreading of other more virulent isolates. These outcomes may help make decisions related to large-scale targeted management actions against ASF in field conditions

Trichomonas vaginalis Infection and Associated Risk Factors in a Socially-Marginalized Female Population in Coastal Peru

Objective. The epidemiology of Trichomonas vaginalis infection among sexually active socially-marginalized women in three urban, coastal Peruvian cities was examined in order to quantify the prevalence of trichomonas infection and identify associated risk factors. Methods. We conducted a cross-sectional, venue-based study of women from socially-marginalized populations in three coastal Peruvian cities. Results. Among the 319 women enrolled, the overall prevalence of trichomonal infection was 9.1% (95% CI, 5.9%–12.3%). The mean age was 26.3 years, and 35.5% reported having had unprotected intercourse with nonprimary partners and 19.8% reported two or more sex partners in the last three months. Trichomonal infection was associated with increased number of sex partners (PR 2.5, 95% CI 1.4–4.6) and unprotected sex with nonprimary partner in the last three months (PR 2.3, 95% CI 1.1–4.9). Conclusions. A moderately high prevalence of trichomonal infection was found among women in our study. Trichomonal infection was associated with unprotected sex and multiple sex partners. Efforts to control the continued spread of trichomonal infection are warranted

Satisfacao dos profissionais e da comunidade com a estrategia da saude da familia

OBJETIVO: Analisar as limitações e os pontos positivos da Estratégia de Saúde da Família na perspectiva dos profissionais da saúde e da comunidade. MÉTODOS: Estudo realizado entre os meses de junho e agosto de 2009, na cidade de Vespasiano, MG, localizada na região Sudeste do Brasil. Para avaliar a Estratégia de Saúde da Família (ESF), foi aplicado questionário em 77 profissionais da saúde e 293 cuidadores de crianças menores de cinco anos. Variáveis como o treinamento das equipes de saúde, acesso da comunidade aos serviços prestados pelas equipes de ESF, comunicação com os pacientes, a atenção prestada à criança e as informações de saúde passadas aos cuidadores foram alguns dos pontos de interesse da investigação. Análises de regressão logística foram utilizadas para se avaliar a significância estatística das variáveis estudadas, bem como os valores de odds ratio e intervalo de confiança. RESULTADOS: A maioria dos profissionais relatou que seus treinamentos foram insuficientes em quantidade, conteúdo e metodologia utilizada. Os cuidadores e profissionais identificaram semelhantes limitações da Estratégia de Saúde da Família (os serviços inacessíveis à comunidade, falta de treinamento e número insuficiente de profissionais) e também pontos fortes semelhantes (a comunicação entre agentes comunitários e comunidade, fornecimento de informações educacionais e foco na atenção à criança). Como recomendações para a melhoria do programa foram apontados: a necessidade de mais médicos e especialistas, treinamentos em maior quantidade e qualidade e melhoria na marcação de consultas. A satisfação dos cuidadores foi relacionada aos benefícios ofertados, como as visitas dos profissionais às casas (OR 5,8; IC95% 2,8;12,1), boa relação entre comunidade e profissionais (OR 4,8; IC95% 2,5;9,3) e foco na saúde da família (OR 4,1; IC95% 1,6;10,2). Problemas como número insuficiente de profissionais (OR 0,3; IC95% 0,2;0,6), dificuldade de acesso aos serviços prestados pela ESF (OR 0,2; IC95% 0,1;0,4) e qualidade ruim dos serviços ofertados (OR 0,3; IC95% 0,1;0,6) foram relacionados à insatisfação da comunidade com a ESF. De uma maneira geral, a maioria dos cuidadores (62%) mostraram estar satisfeitos com os serviços prestados pela ESF. CONCLUSÕES: Identificar as limitações e os pontos positivos da ESF pode gerar uma valiosa informação, que auxiliará na melhoria dessa estratégia para a atenção primária no Brasil.OBJETIVO: Analizar las limitaciones y los puntos positivos de la Estrategia de Salud de la Familia en la perspectiva de los profesionales de la salud y de la comunidad. MÉTODOS: Estudio realizado entre los meses de Junio y Agosto de 2009, en la ciudad de Vespasiano, MG, localizada en el la región sureste de Brasil. Para evaluar la Estrategia de la Salud de la Familia (ESF), se aplicó cuestionario en 77 profesionales de la salud y 293 cuidadores de niños menores de cinco años. Las Variables, entrenamiento de los grupos de salud, acceso de la comunidad a los servicios suministrados por los grupos de ESF, comunicación con los pacientes, la atención suministrada al niño y las informaciones de salud entregadas a los cuidadores, fueron algunos de los puntos de interés de la investigación. Los análisis de regresión logística se utilizaron para evaluar la significancia estadística de las variables estudiadas, así como los valores de odds ratio (OR) e intervalo de confianza (IC). RESULTADOS: La mayoría de los profesionales mencionó que sus entrenamientos fueron insuficientes en cantidad, contenido y metodología utilizada. Los cuidadores y profesionales identificaron limitaciones semejantes de la ESF (los servicios inaccesibles a la comunidad, falta de entrenamiento e insuficiente número de profesionales) y también semejantes puntos fuertes (la comunicación entre agentes comunitarios y comunidad, suministro de informaciones educativas y énfasis en la atención del niño). Como recomendaciones para mejorar el programa fueron señalados: la necesidad de más médicos y especialistas, entrenamientos en mayor cantidad y calidad y mejoría al concertar cita con médicos. La satisfacción de los cuidadores fue relacionada con los beneficios ofertados, como las visitas de los profesionales a las casas (OR 5,8; IC95% 2,8;12,1), buena relación entre comunidad y profesionales (OR 4,8; IC95% 2,5;9,3) y, énfasis en la salud de la familia (OR 4,1; IC 95% 1,6; 10,2). Problemas como insuficiente número de profesionales (OR 0,3; IC95% 0,2;0,6), dificultad en el acceso a los servicios suministrados por la ESF (OR 0,2; IC95% 0,1;0,4) y mala calidad de los servicios ofertados (OR 0,3; IC95% 0,1;0,6) se relacionaron con la insatisfacción de la comunidad con la ESF. De una forma general, la mayoría de los cuidadores (62%) mostraron estar satisfechos con los servicios suministrados por la ESF. CONCLUSIONES: Identificar las limitaciones y los puntos positivos de la ESF puede generar una información valiosa que ayudará en la mejoría de ésta estrategia de atención primaria en Brasil.OBJECTIVE: To analyze the strengths and limitations of the Family Health Strategy from the perspective of health care professionals and the community. METHODS: Between June-August 2009, in the city of Vespasiano, Minas Gerais State, Southeastern Brazil, a questionnaire was used to evaluate the Family Health Strategy (ESF) with 77 healthcare professionals and 293 caregivers of children under five. Health care professional training, community access to health care, communication with patients and delivery of health education and pediatric care were the main points of interest in the evaluation. Logistic regression analysis was used to obtain odds ratios and 95% confidence intervals as well as to assess the statistical significance of the variables studied. RESULTS: The majority of health care professionals reported their program training was insufficient in quantity, content and method of delivery. Caregivers and professionals identified similar weaknesses (services not accessible to the community, lack of healthcare professionals, poor training for professionals) and strengths (community health worker-patient communications, provision of educational information, and pediatric care). Recommendations for improvement included: more doctors and specialists, more and better training, and scheduling improvements. Caregiver satisfaction with the ESF was found to be related to perceived benefits such as community health agent household visits (OR 5.8, 95%CI 2.8;12.1), good professional-patient relationships (OR 4.8, 95%CI 2.5;9.3), and family-focused health (OR 4.1, 95%CI 1.6;10.2); and perceived problems such as lack of personnel (OR 0.3, 95%CI 0.2;0.6), difficulty with access (OR 0.2, 95%CI 0.1;0.4), and poor quality of care (OR 0.3, 95%CI 0.1;0.6). Overall, 62% of caregivers reported being generally satisfied with the ESF services. CONCLUSIONS: Identifying the limitations and strengths of the Family Health Strategy from the healthcare professional and caregiver perspective may serve to advance primary community healthcare in Brazil