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Most tropical forests are threatened by a myriad of human-induced disturbances, associated with land use changes, altered fire regimes and direct deforestation. The combined effect of multiple disturbances can shift forests towards a new, resilient state that is qualitatively distinct in structure, species composition and function. We found that abandoned pastures affected by fires in the Brazilian Atlantic forest showed similarity in terms of vegetation structure and plant functional traits to a savanna-like ecosystem. Burned communities exhibited more C grass cover, higher proportion of resprouts and lower canopy cover as compared to the old-growth forest. Moreover, 79% of woody species at the burned sites are generalists with a widespread distribution, which includes the cerrado (Brazilian savanna). Woody species composition was strikingly different from old-growth forests, since burned sites were dominated by Moquiniastrum polymorphum (Less.) G. Sancho (Asteraceae), a fire-resistant species with a ruderal behavior that was absent in the old-growth forests. The results observed in this study provide biological evidence for an arrested succession with the establishment of a savanna-like ecosystem as an alternative stable state. These findings reinforce the notion that the establishment of an alternative stable state (e.g., savanna-like state) hypothesis for the Brazilian Atlantic Forest should be considered, especially under the current climate change scenarios., This researchwas partly funded by PROBIO II (BIRD/MMA/MCTI/JBRJ). Sansevero, J.B.B. received a PhD scholarship from the Coordenacão de Aperfeicoamento de Pessoal de Nível Superior(CAPES) and the Programa de Doutorado Sanduíche no Exterior(PDSE - CAPES).

The development of easily observable measures of restoration success is essential for monitoring of the ambitious proposed global restoration targets (e.g. The Bonn Challenge; New York Declaration on Forests). Systematic reviews with meta-analyses are a good way to evaluate the performance of different organisms in the monitoring of ecological restoration. Among the arthropods, ants have a long history in environmental monitoring. We compiled a data set and performed a global meta-analysis encompassing studies conducted in different ecosystems around the world to investigate whether richness and composition of species or functional groups (FG) of ant communities can be predicted during the restoration process. Moreover, we aimed to understand the influence of restoration technique (natural regeneration or active restoration), ecosystem type (temperate or tropical), and past land use (mining or pasture) on ant communities in areas undergoing restoration processes. Notwithstanding the varied conditions in which the studies were carried out, our meta-analysis showed that reestablishment of ant FG takes place more quickly than species richness. The recovery of ant diversity is faster in tropical ecosystems and areas under natural regeneration can have higher ant diversity than the reference areas. In temperate ecosystems, mined areas under restoration are less likely to recover the number of species than FG richness. Both species and FG composition were less predictable in our meta-analysis. As the publication of new datasets is increasing, we hope that future meta-analyses can build on the present study to further describe and understand the patterns in ant communities to be used as indicators of ecosystem restoration.

Human land use has extensively degraded ecosystems, leading to biodiversity losses and reducing the provision of ecosystem services (ES). Agroforestry systems have been recommended as a cost-effective strategy that integrates production and biodiversity conservation, yet few studies have quantified the capacity of agroforestry systems to conserve biodiversity and ES provision. Here we quantify the effects of different types of agroforestry systems on biodiversity and ES in the Brazilian Atlantic Forest. We compared values of biodiversity and ES in different agroforestry systems with those found in conventional production systems and in old-growth forests (reference ecosystem). We assessed 72 studies encompassing 143 study sites and 1700 quantitative comparisons. In general, agroforestry and conventional production systems had lower values of mean effect size for biodiversity and ES provision than the reference systems. However, biodiverse agroforestry systems had higher values of mean effect size for biodiversity and ES provision than simple agroforestry systems and conventional production systems. The use of biodiverse agroforestry systems as an alternative production system reduces biodiversity loss and the negative impact on ES in production areas. Agroforestry systems provide up to 45% and 65% more benefits for biodiversity and ES levels, respectively, than conventional production systems; however, these benefits differ according to the type of agroforestry system. Our findings provide empirical evidence that a biodiverse agroforestry system is the best option to enhance biodiversity and ES in degraded areas where production systems based on sustainable management of natural resources are allowed by law. Our results support environmental public policies focused on environmentally-friendly land management practice and forest landscape restoration techniques.

Amblyopia is the most common cause of visual impairment in one eye, with a prevalence of 1-5% in the world population. While amblyopia can be efficiently treated in children, it becomes irreversible in adults, due to the decline in neural plasticity past the end of the visual cortex critical period. Accordingly, no pharmacological approaches are available to rescue visual functions in adult amblyopic subjects. We report that non-invasive intranasal infusion of BDNF increased levels of this neurotrophic factor in V1 and induced a recovery of visual acuity, ocular dominance and visual depth perception in adult amblyopic rats, both in reverse-occluded animals and in those with unrestricted binocular sight. Visual recovery was long-lasting, and was prevented by pharmacological blockade of TrkB signaling in the visual cortex. These results underscore the possibility to replace invasive BDNF central administration with a safe procedure of potential interest in a number of currently still cureless central nervous system pathologies. This article is part of the Special Issue entitled "Neurobiology of Environmental Enrichment".

Fiscal modules (FMs) were created to facilitate the collection of the rural territorial tax in Brazil. In theory, the area of a FM should be enough for a family to have income, survive, and thrive. The current Native Vegetation Protection Law (Law 12.651/2012) gives equal treatment to all people who own up to four FMs through the Environmental Regularization Program for small properties and family agriculture. Thus, FMs are parameters for flexible land allocation, reducing the area in which the restoration of native vegetation is mandatory. In this study, we sought to describe the history of the creation of FMs to verify the correlations between current agricultural and socioeconomic indicators and FM size. We used a case study in the state of Rio de Janeiro in southeast Brazil to analyze how updating the FM affects the Environmental Regularization Program proposed by the Native Vegetation Protection Law. FMs were created in 1979 and set in 1980, but have never been updated. Current data on land use, rate of deforestation, and productivity in rural areas should lead to changes in the FM size and value. Analyzing the data from municipalities in the state of Rio de Janeiro, we found that the groups formed in the cluster analysis differed from the existing FM groups in the state, which range from 5 to 35 ha. This difference may be a consequence of the failure to update the FM parameters, because updating the FM definition may result in less hectares in each FM. This would result in a larger area to be restored, according to the Environmental Regularization Program, and would thus favor the overall goals of forest restoration.

We aimed to determine which factors explain the relative abundances of climbing plants in a tropical sandy coastal plant community, locally called restinga, in SE-Brazil, where facilitation is an important mechanism controlling shrub and tree diversity. The factors examined were: associations with host trees and shrubs, environmental conditions, associations with herbs and space. We surveyed a total of 84 vegetation patches within two hectares of open restinga vegetation. Climbers, trees, shrubs and herbs were sampled using an adapted cover pin frame approach. Partial constrained ordination (pRDA) was used to partition the variation of climber species relative abundances into four sources: trees and shrubs relative abundances, herb species relative abundances, environmental variables (patch architecture and size), and the spatial coordinates. Linear models were used to model the relationship of climber diversity as a function of the environmental factors. A total of 12 climber species belonging to 5 families were recorded. Associations between climber species with subordinate trees and shrubs were the major determinants of climber presence in these vegetation patches. The support for growth created by these trees and shrubs had a secondary role in explaining these patterns. We found no relationship between tree dominance and climber species dominance in each patch. However, most climbers were associated with subordinate shrubs. Trellis availability at the first stratum was related to greater climber diversity suggesting that subordinate trees and shrubs may be crucial to promote climber diversity in this plant community. Space and associations with herbs had a minor contribution to overall variation. While 15 years of research in the site associated local floristic diversity to dominant trees, our results demonstrate that climber diversity in this community is governed by interactions with subordinate host woody species related to the environmental support for growth created by such trees and shrubs.

Type I diabetes mellitus (IDDM) is associated with an increased cardiovascular risk, and eligibility protocols for simultaneous pancreas-kidney transplantation (SPKT) are consequently accurate for preoperative cardiovascular assessment. According to our algorithm, coronary angiography in SPKT candidates is indicated for patients not only experiencing previous cardiac events or symptoms, but also those with long-standing diabetes (more than 25 years) and/or age over 45 years. Furthermore, a basal transthoracic echocardiographic exam (TTE) is performed to assess cardiac volumes, left ventricular mass, systolic function, and kinesis. The aims of this study were to evaluate perioperative cardiac morbidity and mortality in 18 SPKT-eligible patients, divided into two groups on the basis of the presence/absence of angiographically evident coronary artery disease (CAD), as well as to assess the impact of left ventricular hypertrophy (LVH) on cardiac complications. Cardiac intraoperative morbidity and mortality and postoperative mortality and major morbidity were absent; minor cardiac morbidity consisted only of silent ischemic ECG alterations, without significant differences between groups, although the incidence seemed to be higher in the CAD-positive population. LVH detected preoperatively by TTE exam also failed to correlate with the incidence of such complications. Selection of SPKT candidates by coronary angiography may have positive effects on perioperative cardiac morbidity and mortality. A larger sample size is needed to give the study statistical power. Medium- and long-term follow-up studies are warranted to evaluate the effects of preoperative selection on survival rates.