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Abnormal visual experience during development resulting from an imbalance in the activity of the two eyes can lead to permanent severe visual deficits, a pathology called amblyopia (lazy eye). While this condition is extremely difficult to treat in adults, current interventions can elicit significant amounts of visual recovery when performed in juveniles before the end of the critical period, even if the achievable results can be unsatisfactory due to the progressive decline in visual cortical plasticity. Similarly to human subjects, rodents becoming amblyopic due to early visual deprivation can display spontaneous functional recovery if the deprivation ends within the critical period time window. With the aim to investigate the impact of non-invasive strategies able to increase this spontaneous potential for plasticity, we wondered whether physical exercise could speed up spontaneous recovery of visual functions in juvenile amblyopic rats. Our results show that physical exercise accelerates visual recovery in adolescent rats, encouraging application of behavioral plasticizing treatments to promote recovery in young individuals.

Tropical forests have high species richness, being considered the most diverse and complex ecosystems in the world. Research on the variation and maintenance of biodiversity in these ecosystems is important for establishing conservation strategies. The main objective of this study was to test the Spectral Variation Hypothesis through associations between species diversity and richness measured in the field and hyperspectral data collected by a Remotely Piloted Aircraft (RPA) in areas with secondary tropical forest in the Brazilian Atlantic Forest biome. Specific objectives were to determine which dispersion measurements, standard deviation (SD) or coefficient of variation (CV), estimated for the n pixels occurring within each sampling unit, better explains species diversity; the effects of pixel size on the direction and intensity of this relationship; and the effects of shaded pixels within each sampling unit. The spectral variability hypothesis was confirmed for the Atlantic Forest biome, with R2 of 0.83 for species richness and 0.76 and 0.69 for the Shannon and Simpson diversity indices, respectively, using 1.0 m illuminated pixels. The dispersion (CV and SD) of hyperspectral bands were most strongly correlated with taxonomic diversity and richness in the red-edge and near-infrared (NIR) regions of the electromagnetic spectrum. Pixel size affected R2 values, which were higher for 1.0 m pixels (0.83) and lower for 10.0 m pixels (0.71). Additionally, illuminated pixels had higher R2 values than those under shadow effects. The main dispersion variables selected as metrics for regression models were mean CV, CV for the 726.7 nm band, and SD for the 742.3 and 933.4 nm bands. Our results suggest that spectral diversity can serve as a proxy for species diversity in the Atlantic Forest. However, factors that can affect this relationship, such as taxonomic and spectral diversity metrics used, pixel size, and shadow effects in images, should be considered.

We differentiate the event-by-event n-γ multiplicity data from Cf252(sf) with respect to the energies of the emitted particles as well as their relative angles of emission. We determine that neutron emission enhances γ-ray emission around 0.7 and 1.2 MeV, but the only directional alignment was observed for Eγ≤0.7 MeV and tended to be parallel and antiparallel to neutrons emitted in the same event. The emission of γ rays at other energies was determined to be nearly isotropic. The presence of the emission and alignment enhancements is explained by positive correlations between neutron emission and quadrupole γ-ray emission along rotational bands in the de-exciting fragments. This observation corroborates the hypothesis of positive correlations between the angular momentum of a fragment and its intrinsic excitation energy. The results of this work are especially relevant in view of the recent theoretical and experimental interest in the generation of angular momentum in fission. Specifically, we have determined an alignment of the fragment's angular momenta in a direction perpendicular to the direction of motion. We interpret the lack of n-γ angular correlations for fission fragments near closed shells as a weakening of the alignment process for spherical nuclei. Lastly, we have observed that statistical γ rays are emitted isotropically, indicating that the average angular momentum removed by this radiation is small. These results, and the analysis tools presented in this work, represent a stepping stone for future analysis of n-γ emission correlations and their connection to angular momentum properties.

The emission of neutrons and γ rays by fission fragments reveal important information about the properties of fragments immediately following scission. The initial fragment properties, correlations between fragments, and emission competition give rise to correlations in neutron-γ emission. Recent theoretical and experimental advances have been proposed to explain the mechanism of angular momentum generation in fission, which would result in observable signature in neutron-γ emission correlations. In this paper, we present a novel analysis method of neutrons and γ rays emitted by fission fragments that allows us to discern structure in the observed correlations. We have analyzed data collected on Cf252(sf) at the Chi-Nu array at the Los Alamos Neutron Science Center. Through our analysis of the energy-differential neutron-γ multiplicity covariance, we have observed enhanced neutron-γ correlations, corresponding to rotational band γ-ray transitions, at γ-ray energies of 0.7 and 1.2 MeV. To shed light on the origin of this structure, we compare the experimental data with the predictions of three model calculations. The origin of the observed correlation structure is understood in terms of a positive spin-energy correlation in the generation of angular momentum in fission.

Abnormal visual experience during development resulting from an imbalance in the activity of the two eyes can lead to permanent severe visual deficits, a pathology called amblyopia (lazy eye). While this condition is extremely difficult to treat in adults, current interventions can elicit significant amounts of visual recovery when performed in juveniles before the end of the critical period, even if the achievable results can be unsatisfactory due to the progressive decline in visual cortical plasticity. Similarly to human subjects, rodents becoming amblyopic due to early visual deprivation can display spontaneous functional recovery if the deprivation ends within the critical period time window. With the aim to investigate the impact of non-invasive strategies able to increase this spontaneous potential for plasticity, we wondered whether physical exercise could speed up spontaneous recovery of visual functions in juvenile amblyopic rats. Our results show that physical exercise accelerates visual recovery in adolescent rats, encouraging application of behavioral plasticizing treatments to promote recovery in young individuals. [ABSTRACT FROM AUTHOR]

The phenomenon of neural plasticity pertains to the intrinsic capacity of neurons to undergo structural and functional reconfiguration through learning and experiential interaction with the environment. These changes could manifest themselves not only as a consequence of various life experiences but also following therapeutic interventions, including the application of noninvasive brain stimulation (NIBS) and psychotherapy. As standalone therapies, both NIBS and psychotherapy have demonstrated their efficacy in the amelioration of psychiatric disorders' symptoms, with a certain variability in terms of effect sizes and duration. Consequently, scholars suggested the convenience of integrating the two interventions into a multimodal treatment to boost and prolong the therapeutic outcomes. Such an approach is still in its infancy, and the physiological underpinnings substantiating the effectiveness and utility of combined interventions are still to be clarified. Therefore, this opinion paper aims to provide a theoretical framework consisting of compelling arguments as to why adding NIBS to psychotherapy can promote therapeutic change. Namely, we will discuss the physiological effects of the two interventions, thus providing a rationale to explain the potential advantages of a combined approach. [ABSTRACT FROM AUTHOR]

Tropical forests have high species richness, being considered the most diverse and complex ecosystems in the world. Research on the variation and maintenance of biodiversity in these ecosystems is important for establishing conservation strategies. The main objective of this study was to test the Spectral Variation Hypothesis through associations between species diversity and richness measured in the field and hyperspectral data collected by a Remotely Piloted Aircraft (RPA) in areas with secondary tropical forest in the Brazilian Atlantic Forest biome. Specific objectives were to determine which dispersion measurements, standard deviation (SD) or coefficient of variation (CV), estimated for the n pixels occurring within each sampling unit, better explains species diversity; the effects of pixel size on the direction and intensity of this relationship; and the effects of shaded pixels within each sampling unit. The spectral variability hypothesis was confirmed for the Atlantic Forest biome, with R2 of 0.83 for species richness and 0.76 and 0.69 for the Shannon and Simpson diversity indices, respectively, using 1.0 m illuminated pixels. The dispersion (CV and SD) of hyperspectral bands were most strongly correlated with taxonomic diversity and richness in the red-edge and near-infrared (NIR) regions of the electromagnetic spectrum. Pixel size affected R2 values, which were higher for 1.0 m pixels (0.83) and lower for 10.0 m pixels (0.71). Additionally, illuminated pixels had higher R2 values than those under shadow effects. The main dispersion variables selected as metrics for regression models were mean CV, CV for the 726.7 nm band, and SD for the 742.3 and 933.4 nm bands. Our results suggest that spectral diversity can serve as a proxy for species diversity in the Atlantic Forest. However, factors that can affect this relationship, such as taxonomic and spectral diversity metrics used, pixel size, and shadow effects in images, should be considered. [ABSTRACT FROM AUTHOR]

Beatrice Vignoli et al. examine potential molecular mechanisms of long-term storage information in mice. Their results suggest that astrocytes may help convert neuronal BDNF precursor into active prodomain and mature forms to enhance post-synaptic signaling and memory, providing further insight into the development of memory circuits.

RESUMO O monitoramento das práticas de restauração é um processo caro, mas essencial para verificar o seu sucesso. Uma forma de reduzir os custos amostrais é por meio da utilização de indicadores de biodiversidade, termo utilizado para um grupo funcional ou taxonômico que é concordante com outro grupo. O objetivo deste trabalho foi avaliar a concordância entre a riqueza e a composição de plantas regenerantes, formigas e outros artrópodes sob o dossel de quatro espécies arbóreas em uma área de restauração na Mata Atlântica, Brasil, bem como determinar a relação das comunidades biológicas com parâmetros ambientais e espaciais. Foi encontrado que as variáveis ambientais, muitas vezes ligadas a identidade da árvore, são preponderantes para determinar a relação entre formigas, outros artrópodes e plantas regenerantes. Além disso, as formigas demonstraram ser indicadores fracos da diversidade e composição de plantas regenerantes e outros artrópodes e essa relação não foi guiada pelas variáveis ambientais e espaciais. Assim, os resultados aqui encontrados recomendam cautela ao utilizar formigas como indicadores de biodiversidade de plantas e outros artrópodes em programas de monitoramento na Mata Atlântica.

Disentangling the mechanisms that shape community assembly across diversity gradients is a central matter in ecology. While many studies have explored community assembly through species average trait values, there is a growing understanding that intraspecific trait variation (ITV) can also play a critical role in species coexistence. Classic biodiversity theory hypothesizes that higher diversity at species-rich sites can arise from narrower niches relative to species-poor sites, which would be reflected in reduced ITV as species richness increases. To explore how ITV in woody plant communities changes with species richness, we compiled leaf trait data (leaf size and specific leaf area) in a total of 521 woody plant species from 21 forest communities that differed dramatically in species richness, ranging from boreal to tropical rainforests. At each forest, we assessed ITV as an estimate of species niche breadth and we quantified the degree of trait overlap among co-occurring species as a measure of species functional similarity. We found ITV was relatively invariant across the species richness gradient. In addition, we found that species functional similarity increased with diversity. Contrary to the expectation from classic biodiversity theory, our results rather suggest that neutral processes or equalizing mechanisms can be acting as potential drivers shaping community assembly in hyperdiverse forests.

An abnormal visual experience early in life, caused by strabismus, unequal refractive power of the eyes, or eye occlusion, is a major cause of amblyopia (lazy eye), a highly diffused neurodevelopmental disorder severely affecting visual acuity and stereopsis abilities. Current treatments for amblyopia, based on a penalization of the fellow eye, are only effective when applied during the juvenile critical period of primary visual cortex plasticity, resulting mostly ineffective at older ages. Here, we developed a new paradigm of operant visual perceptual learning performed under conditions of conventional (binocular) vision in adult amblyopic rats. We report that visual perceptual learning induced a marked and long-lasting recovery of visual acuity, visual depth perception abilities and binocular matching of orientation preference, and we provide a link between the last two parameters.

Background: Physical activity has been recently shown to enhance adult visual cortical plasticity, both in human subjects and animal models. While physical activity activates mitochondrial oxidative metabolism leading to a transient production of reactive oxygen species, it remains unknown whether this process is involved in the plasticizing effects elicited at the visual cortical level. Results: Here, we investigated whether counteracting oxidative stress through a dietary intervention with antioxidants (vitamins E and C) interferes with the impact of physical exercise on visual cortex plasticity in adult rats. Antioxidant supplementation beyond the closure of the critical period blocked ocular dominance plasticity in response to eye deprivation induced by physical activity in adult rats. Conclusions: Antioxidants exerted their action through a mithormetic effect that involved dampening of oxidative stress and insulin-like growth factor 1 (IGF-1) signaling in the brain.

In the last decades, the effects of sedentary lifestyles have emerged as a critical aspect of modern society. Interestingly, recent evidence demonstrated that physical exercise plays an important role not only in maintaining peripheral health but also in the regulation of central nervous system function. Many studies have shown that physical exercise promotes the release of molecules, involved in neuronal survival, differentiation, plasticity and neurogenesis, from several peripheral organs. Thus, aerobic exercise has emerged as an intriguing tool that, on one hand, could serve as a therapeutic protocol for diseases of the nervous system, and on the other hand, could help to unravel potential molecular targets for pharmacological approaches. In the present review, we will summarize the cellular interactions that mediate the effects of physical exercise on brain health, starting from the factors released in myocytes during muscle contraction to the cellular pathways that regulate higher cognitive functions, in both health and disease.

Durante toda a sua exposição sobre o juízo de gosto, que ocupa majoritariamente a primeira parte (§1 - §60) da CRÍTICA DA FACULDADE DO JUÍZO (CRITIQUE OF JUDGMENT), Kant só abre espaço para investigação da figura do gênio ao tratar da arte, no §43. Neste artigo pretendo mostrar que a investigação sobre a arte traz um problema considerável para a estrutura do que foi antes exposto sobre o juízo de gosto. Este problema pode ser expresso na seguinte pergunta: como conciliar beleza e regra, dentro do pensamento kantiano sobre o belo? Através da relação entre arte e natureza na noção kantiana de gênio.

Abstract: Introduction: Assessment is a critical part of learning and validity is arguably its most important aspect. However, different views and beliefs led to a fragmented conception of the validity meaning, with an excessive focus on psychometric methods and scores, neglecting the consequences and utility of the test. The last decades witnessed the creation of a significant number of tests to assess different aspects of the medical profession formation, but researchers frequently limit their conclusions to the consistency of their measurements, without any further analysis on the educational and social impacts of the test. The objective of this work is to determine the predominant concept of validity in medical education assessment studies. Method: The authors conducted a bibliometric research of the literature about studies on the assessment of learning of medical students, to determine the prevalent concept of validity. The research covered a period from January 2001 to august 2019. The studies were classified in two categories based on their approach to validity: (1)” fragmented validity concept” and (2)” unified validity concept”. To help with validity arguments, the studies were also classified based on Miller’s framework for clinical assessment. Results: From an initial search resulting in 2823 studies, 716 studies were selected based on the eligibility criteria, and from the selected list, of which 693 (96,7%) were considered studies of the fragmented validity concept, which prioritized score results over an analysis of the test's utility, and only 23 studies (3,2%) were aligned with a unified view of validity, showing an explicit analysis of the consequences and utility of the test. Although the last decade witnessed a significant increase in the number of assessment studies, this increase was not followed by a significant change in the validity concept. Conclusions: This bibliometric analysis demonstrated that assessment studies in medical education still have a fragmented concept of validity, restricted to psychometric methods and scores. The vast majority of studies are not committed to the analysis about the utility and educational impact of an assessment policy. This restrictive view can lead to the waste of valuable time and resources related to assessment methods without significant educational consequences.

Fire may divert or arrest natural regeneration in abandoned pastures throughout the tropics, transforming them to low-resilience systems that do not recover even in the absence of disturbances. Understanding regeneration in degraded landscapes is crucial to decision-making and predicting the outcome of passive or active restoration actions. We aimed to understand the effects of intensifying fire regimes on post-fire natural regeneration in sites degraded by logging and fire in the Brazilian Atlantic Forest. We studied five areas with different fire regimes (i.e., different fire frequencies and post-fire regeneration time), dominated by Moquiniastrum polymorphum (Asteraceae), a widely-distributed species with fire resistance traits. We analyzed differences in structure, diversity, the amplitude of the species' geographic distribution, and floristic composition. We recorded Leaf Area Index and grass cover to understand the effect of canopy closure on fire exclusion and analyzed functional traits related to succession and response to fire (specific leaf area, height, wood density, bark thickness, seed mass). Post-fire regeneration was slow and fire-prone and dominance by M. polymorphum decreased with less disturbance, as other species entered the communities. Structure, diversity, and functional composition recovered along the gradient but did not reach old-growth values. The taxonomic composition was strikingly different in burned areas and forests, irrespective of fire history. Natural regeneration followed a divergent trajectory, marked by the establishment of other widely-distributed species, which suggests a long-term floristic impoverishment. The establishment of M. polymorphum allows these pastures to exit grass-fire cycles. Longer post-fire recovery and fewer fire events allow for canopy closure, grass exclusion, and eventually fire suppression. This two-step dynamic breaks a crucial barrier for restoration from degraded pastures and represents a more desirable state than pastures. However, relying only upon natural regeneration results in impoverished secondary forests. Given the pervasive effects of deforestation and fire, natural regeneration observed in tropical landscapes may correspond to impoverished new secondary forests that fail to attain conservation targets for the biome. Preventing future fires and controlling grass cover in the understory is crucial to avoid their retrogression to pastures and to treat them as regeneration templates for active restoration.

Introdução: A procura excessiva nos serviços de urgência/emergência geralmente se dá devido a problemas que poderiam ser solucionados nos serviços de atenção básica à saúde. Os usuários procuram o serviço de emergência muitas vezes por desconhecerem a finalidade deste, gerando enormes filas de espera. Objetivos: Descrever o perfil sociodemográfico e clínico dos usuários de um pronto socorro (PS) de uma instituição do Vale do Paraíba. Métodos: O estudo segue a abordagem quantitativa, do tipo descritivo, transversal e de caráter documental, fundamentado na análise de dados coletados diretamente das Fichas de Atendimentos dos pacientes atendidos no PS. A amostra consistiu de 774 atendimentos nos meses de janeiro, fevereiro e março de 2015. Resultados: Observou-se que 39% dos pacientes tinham entre 19 e 25 anos de idade, 55% eram do sexo feminino, 63% eram pertencentes à cidade de Aparecida, 82% eram da zona urbana, 98% tinham prescrição médica, 34% não realizaram os exames, 29% tinham hipótese diagnóstica de sintomas gripais, 81% dos pacientes tiveram alta e 16% dos pacientes tinham histórico clínico de cefaleia. Conclusão: Os atendimentos apontaram para a necessidade de orientação dos usuários na utilização do serviço de atenção básica. Palavras-Chave: Urgência e emergência; Atendimento em pronto-socorro; Enfermagem em emergência ABSTRACT Introduction: The over going in the emer-gency service is usually because of the problems which could be solved at the primary health service. The patients look for the emergency service many times because they do not know exactly the finality, which results in a huge waiting line. Aims: To describe the clinic and soci-odemographic profile of the emergency users in an institution in Vale do Paraíba, São Paulo, Brazil. Methods: A quantitative, descriptive, transversal, the character documental, based on the data analysis collected from the attendance sheets of the patients who went to the emergency. The sample of this study was 774 attendances in the months of January, February, and March of 2015. Results: It was observed that 39% of the patients were between 19 and 25 years old, 55% female gender, 63% were from the city of Aparecida (Brazil), 82% were from the urban area, 98% had medical recipe, 34% did not do the exami-nation, 29% had symptoms of flu, 81% of the patients had been discharged from the hospital, and 16% of the patients had got a headache. Conclusion: The attendance showed the need of clients’ education to use the services in the primary health area. Keywords: Emergency department; ER visits; Emergency nursing

The Brazilian Atlantic Forest has undergone adverse land-use change due to deforestation for urbanization and agriculture. Numerous restoration initiatives have been taken to restore its ecosystem services. Deforested areas have been restored through active intervention or natural regeneration. Understanding the impact of those different reforestation approaches on soil quality should provide important scientific and practical conclusions on increasing forest cover in the Brazilian Atlantic Forest biome. However, studies evaluating active planting versus natural regeneration in terms of soil recovery are scarce. We evaluate soil dynamics under those two contrasting strategies at an early stage (