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Previous work has shown that tree turnover, tree biomass and large liana densities have increased in mature tropical forest plots in the late twentieth century. These results point to a concerted shift in forest ecological processes that may already be having significant impacts on terrestrial carbon stocks, fluxes and biodiversity. However, the findings have proved controversial, partly because a rather limited number of permanent plots have been monitored for rather short periods. The aim of this paper is to characterize regional-scale patterns of 'tree turnover' (the rate with which trees die and recruit into a population) by using improved datasets now available for Amazonia that span the past 25 years. Specifically, we assess whether concerted changes in turnover are occurring, and if so whether they are general throughout the Amazon or restricted to one region or environmental zone. In addition, we ask whether they are driven by changes in recruitment, mortality or both. We find that: (i) trees 10 cm or more in diameter recruit and die twice as fast on the richer soils of southern and western Amazonia than on the poorer soils of eastern and central Amazonia; (ii) turnover rates have increased throughout Amazonia over the past two decades; (iii) mortality and recruitment rates have both increased significantly in every region and environmental zone, with the exception of mortality in eastern Amazonia; (iv) recruitment rates have consistently exceeded mortality rates; (v) absolute increases in recruitment and mortality rates are greatest in western Amazonian sites; and (vi) mortality appears to be lagging recruitment at regional scales. These spatial patterns and temporal trends are not caused by obvious artefacts in the data or the analyses. The trends cannot be directly driven by a mortality driver (such as increased drought or fragmentation-related death) because the biomass in these forests has simultaneously increased. Our findings therefore indicate that long-acting and widespread environmental changes are stimulating the growth and productivity of Amazon forests.

The high need for root canal treatments in different dental groups continues to be a challenge for professionals; since, it is necessary the knowledge of the techniques, materials, equipment and instruments, as well as of the anatomical variants on which the success or failure depends. Anatomical variations include the presence of a second root canal in lower incisors (SCRII). The present investigation is of a literature review type, articles of the type were included: literature review and descriptive studies, papers in English and Spanish were included; the search was carried out between the months of January and July 2021, in the following databases: Hinari, EBSCO host, Pubmed. The results indicate that the incidence of finding two canals in both lower incisors range from 2% to 77.9%; individually in lower central incisors the prevalence is from 11.90% to 32.50% and in lower lateral incisors, it is found between 17.50% and 58% of cases. The location of the SCRII entrance has been the subject of multiple studies, finding that there is no consensus on this point; since similar percentages have been described among the different thirds (cervical, middle and apical), an influencing factor could be ethnicity. Cone beam computed tomography has gained ground over conventional radiography and the use of magnification as the most effective diagnostic technique; however, it is suggested to carry out a study with Salvadoran patients to obtain a value that guides professionals and thus avoid endodontic treatment failures in said teeth. [ABSTRACT FROM AUTHOR]

Tree growth and longevity trade-offs fundamentally shape the terrestrial carbon balance. Yet, we lack a unified understanding of how such trade-offs vary across the world's forests. By mapping life history traits for a wide range of species across the Americas, we reveal considerable variation in life expectancies from 10 centimeters in diameter (ranging from 1.3 to 3195 years) and show that the pace of life for trees can be accurately classified into four demographic functional types. We found emergent patterns in the strength of trade-offs between growth and longevity across a temperature gradient. Furthermore, we show that the diversity of life history traits varies predictably across forest biomes, giving rise to a positive relationship between trait diversity and productivity. Our pan-latitudinal assessment provides new insights into the demographic mechanisms that govern the carbon turnover rate across forest biomes.

Objective: Describe barriers and challenges in the implementation of the global Mental Health Gap Action Program (mhGAP), and determine the association between facilitators of implementation, accessibility, acceptability, and supervision, in Chocó, Colombia., Methods: Cross-sectional evaluation study, with mixed and sequential methods. Forty-one people participated: 30 health personnel and 11 administrative workers. Five focus groups were formed within the framework of the mhGAP training. The Likert scale of implementation drivers was used to determine factors affecting the strategy, such as system facilitators, accessibility of the strategy, adaptation and acceptability, and training and supervision. Semi-structured interviews were also conducted, with a subsequent thematic analysis., Results: A statistically significant correlation was found between the components of implementation. This was reaffirmed by the information from the interviews. Notable barriers include dispersion, armed conflict, difficulty in changing one's perspective on the area where they live, and administrative problems in accessing treatment. These factors are addressed in a proposed care pathway., Conclusions: With respect to mhGAP in the department of Chocó, despite adequate acceptability, access, and supervision, there are barriers and challenges at the social, geographical, political, cultural, and health administration levels, which could be overcome through implementation of locally-built intersectoral recovery routes.

The forests of Amazonia are among the most biodiverse plant communities on Earth. Given the immediate threats posed by climate and land-use change, an improved understanding of how this extraordinary biodiversity is spatially organized is urgently required to develop effective conservation strategies. Most Amazonian tree species are extremely rare but a few are common across the region. Indeed, just 227 'hyperdominant' species account for >50% of all individuals >10 cm diameter at 1.3 m in height. Yet, the degree to which the phenomenon of hyperdominance is sensitive to tree size, the extent to which the composition of dominant species changes with size class and how evolutionary history constrains tree hyperdominance, all remain unknown. Here, we use a large floristic dataset to show that, while hyperdominance is a universal phenomenon across forest strata, different species dominate the forest understory, midstory and canopy. We further find that, although species belonging to a range of phylogenetically dispersed lineages have become hyperdominant in small size classes, hyperdominants in large size classes are restricted to a few lineages. Our results demonstrate that it is essential to consider all forest strata to understand regional patterns of dominance and composition in Amazonia. More generally, through the lens of 654 hyperdominant species, we outline a tractable pathway for understanding the functioning of half of Amazonian forests across vertical strata and geographical locations.

The sensitivity of tropical forest carbon to climate is a key uncertainty in predicting global climate change. Although short-term drying and warming are known to affect forests, it is unknown if such effects translate into long-term responses. Here, we analyze 590 permanent plots measured across the tropics to derive the equilibrium climate controls on forest carbon. Maximum temperature is the most important predictor of aboveground biomass (-9.1 megagrams of carbon per hectare per degree Celsius), primarily by reducing woody productivity, and has a greater impact per °C in the hottest forests (>32.2°C). Our results nevertheless reveal greater thermal resilience than observations of short-term variation imply. To realize the long-term climate adaptation potential of tropical forests requires both protecting them and stabilizing Earth's climate., (Copyright © 2020 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.)

Background: Ibuprofen (Motrin; Johnson & Johnson) and acetaminophen (APAP, paracetamol) are the most commonly used analgesics in the pediatric emergency department (ED) for managing a variety of acute traumatic and nontraumatic painful conditions. The multimodal pain management of using a combination of ibuprofen plus acetaminophen has the potential to result in greater analgesia., Objective: We compared the analgesic efficacy of a combination of oral ibuprofen plus acetaminophen with either analgesic alone for pediatric ED patients with acute pain., Methods: We performed a randomized, double-blind superiority trial assessing and comparing the analgesic efficacy of a combination of oral ibuprofen (10 mg/kg dose) plus acetaminophen (15 mg/kg per dose) to either analgesic alone for the treatment of acute traumatic and nontraumatic pain in the pediatric ED. Primary outcomes included a difference in pain scores among the three groups at 60 min., Results: We enrolled 90 patients (30 per group). The difference in mean pain scores at 60 min between acetaminophen and combination groups was 0.30 (95% confidence interval [CI] -0.84 to 1.83); between ibuprofen and combination groups was -0.33 (95% CI -1.47 to 0.80); and between acetaminophen and ibuprofen groups was 0.63 (95% CI -0.54 to 1.81). Reductions in pain scores from baseline to 60 min were similar for all patients in each of the three groups. No adverse events occurred in any group., Conclusions: We found similar analgesic efficacy of oral ibuprofen and acetaminophen in comparison with each analgesic alone for short-term treatment of acute pain in the pediatric ED, but the trial was underpowered to demonstrate the analgesic superiority of the combination of oral ibuprofen plus acetaminophen in comparison with each analgesic alone., (Copyright © 2020 Elsevier Inc. All rights reserved.)

We compiled a data set for all tree species collected to date in lowland Amazonian Ecuador in order to determine the number of tree species in the region. This data set has been extensively verified by taxonomists and is the most comprehensive attempt to evaluate the tree diversity in one of the richest species regions of the Amazon. We used four main sources of data: mounted specimens deposited in Ecuadorian herbaria only, specimen records of a large-scale 1-hectare-plot network (60 plots in total), data from the Missouri Botanical Garden Tropicos® database (MO), and literature sources. The list of 2,296 tree species names we provide in this data set is based on 47,486 herbarium records deposited in the following herbaria: Alfredo Paredes Herbarium (QAP), Catholic University Herbarium (QCA), Herbario Nacional del Ecuador (QCNE), Missouri Botanical Garden (MO), and records from an extensive sampling of 29,768 individuals with diameter at breast height (dbh) ≥10 cm recorded in our plot network. We also provide data for the relative abundance of species, geographic coordinates of specimens deposited in major herbaria around the world, whether the species is native or endemic, current hypothesis of geographic distribution, representative collections, and IUCN threat category for every species recorded to date in Amazonian Ecuador. These data are described in Metadata S1 and can be used for macroecological, evolutionary, or taxonomic studies. There are no copyright restrictions; data are freely available for noncommercial scientific use (CC BY 3.0). Please see Metadata S1 (Class III, Section B.1: Proprietary restrictions) for additional information on usage., (© 2019 The Authors. Ecology © 2019 The Ecological Society of America.)

Using complementary metrics to evaluate phylogenetic diversity can facilitate the delimitation of floristic units and conservation priority areas. In this study, we describe the spatial patterns of phylogenetic alpha and beta diversity, phylogenetic endemism, and evolutionary distinctiveness of the hyperdiverse Ecuador Amazon forests and define priority areas for conservation. We established a network of 62 one-hectare plots in terra firme forests of Ecuadorian Amazon. In these plots, we tagged, collected, and identified every single adult tree with dbh ≥10 cm. These data were combined with a regional community phylogenetic tree to calculate different phylogenetic diversity (PD) metrics in order to create spatial models. We used Loess regression to estimate the spatial variation of taxonomic and phylogenetic beta diversity as well as phylogenetic endemism and evolutionary distinctiveness. We found evidence for the definition of three floristic districts in the Ecuadorian Amazon, supported by both taxonomic and phylogenetic diversity data. Areas with high levels of phylogenetic endemism and evolutionary distinctiveness in Ecuadorian Amazon forests are unprotected. Furthermore, these areas are severely threatened by proposed plans of oil and mining extraction at large scales and should be prioritized in conservation planning for this region.

While studying ecological patterns at large scales, ecologists are often unable to identify all collections, forcing them to either omit these unidentified records entirely, without knowing the effect of this, or pursue very costly and time-consuming efforts for identifying them. These "indets" may be of critical importance, but as yet, their impact on the reliability of ecological analyses is poorly known. We investigated the consequence of omitting the unidentified records and provide an explanation for the results. We used three large-scale independent datasets, (Guyana/ Suriname, French Guiana, Ecuador) each consisting of records having been identified to a valid species name (identified morpho-species - IMS) and a number of unidentified records (unidentified morpho-species - UMS). A subset was created for each dataset containing only the IMS, which was compared with the complete dataset containing all morpho-species (AMS: = IMS + UMS) for the following analyses: species diversity (Fisher's alpha), similarity of species composition, Mantel test and ordination (NMDS). In addition, we also simulated an even larger number of unidentified records for all three datasets and analyzed the agreement between similarities again with these simulated datasets. For all analyses, results were extremely similar when using the complete datasets or the truncated subsets. IMS predicted ≥91% of the variation in AMS in all tests/analyses. Even when simulating a larger fraction of UMS, IMS predicted the results for AMS rather well. Using only IMS also out-performed using higher taxon data (genus-level identification) for similarity analyses. Finding a high congruence for all analyses when using IMS rather than AMS suggests that patterns of similarity and composition are very robust. In other words, having a large number of unidentified species in a dataset may not affect our conclusions as much as is often thought.

Ecological orthodoxy suggests that old-growth forests should be close to dynamic equilibrium, but this view has been challenged by recent findings that neotropical forests are accumulating carbon and biomass, possibly in response to the increasing atmospheric concentrations of carbon dioxide. However, it is unclear whether the recent increase in tree biomass has been accompanied by a shift in community composition. Such changes could reduce or enhance the carbon storage potential of old-growth forests in the long term. Here we show that non-fragmented Amazon forests are experiencing a concerted increase in the density, basal area and mean size of woody climbing plants (lianas). Over the last two decades of the twentieth century the dominance of large lianas relative to trees has increased by 1.7-4.6% a year. Lianas enhance tree mortality and suppress tree growth, so their rapid increase implies that the tropical terrestrial carbon sink may shut down sooner than current models suggest. Predictions of future tropical carbon fluxes will need to account for the changing composition and dynamics of supposedly undisturbed forests.

The purpose of this study was to characterize the injection and sexual risk behaviors of a cohort of active drug injectors who have initiated injection within the past 4 years and to compare their behaviors with the risk behaviors of long-term injectors who have been injecting drugs since 1984. A stratified, network-based sample was used to recruit injection drug users from the streets in Miami-Dade, Florida. After screening for eligibility, which included a urine test to confirm current drug use, participants were administered a structured questionnaire that included basic demographic information, drug-use history, and HIV risk behavior practices. Both injector groups displayed a high level of HIV injection risk behavior. Although new initiates into injection demonstrated lower risk behavior than long-term injectors at the first injection episode, the current risk behavior between new and long-term injectors is similar.

This exploratory study was conducted with the purpose of enumerating both particular social stressors (e.g., the presence of trauma) and the incidence of a comorbid diagnosis (i.e., personality disorder[s] and substance abuse) on a sample of women in a residential therapeutic community. The women in the study were assessed within the first 3 weeks following admission into drug treatment, and then again 6 months after leaving the program. The initial assessment generally took 2 hours and consisted of the Structured Clinical Inventory for DSM-III-R-Patient edition (SCID-II), Addiction Severity Index (ASI), and the Millon Clinical Multiaxial Inventory-II (MCMI-II). Clinically significant scores on the MCMI-II antisocial and borderline personality scales were noted in this study. This study found women with histories of delinquent and/or criminal behavior before drug use were more likely to have used more types of drugs and have used multiple drugs together. These women also tended to have had a history of being abused, either emotionally, physically, or sexually. This group was also less successful on all outcome measures during 6-month follow-up. Moreover, the lifetime incidence of emotional, physical, and sexual abuse reported for this group at the baseline assessment was high--57.1% emotional abuse, 48.9% physical abuse, and 39.7% sexual abuse. These results are consistent with the research literature that indicates abuse plays a central role in the development and chronic effect of personality disorders and, in particular, posttraumatic stress disorder.