Species occurrence records provide the basis for many biodiversity studies. They derive from georeferenced specimens deposited in natural history collections and visual observations, such as those ...obtained through various mobile applications. Given the rapid increase in availability of such data, the control of quality and accuracy constitutes a particular concern. Automatic filtering is a scalable and reproducible means to identify potentially problematic records and tailor datasets from public databases such as the Global Biodiversity Information Facility (GBIF;
http://www.gbif.org
), for biodiversity analyses. However, it is unclear how much data may be lost by filtering, whether the same filters should be applied across all taxonomic groups, and what the effect of filtering is on common downstream analyses. Here, we evaluate the effect of 13 recently proposed filters on the inference of species richness patterns and automated conservation assessments for 18 Neotropical taxa, including terrestrial and marine animals, fungi, and plants downloaded from GBIF. We find that a total of 44.3% of the records are potentially problematic, with large variation across taxonomic groups (25–90%). A small fraction of records was identified as erroneous in the strict sense (4.2%), and a much larger proportion as unfit for most downstream analyses (41.7%). Filters of duplicated information, collection year, and basis of record, as well as coordinates in urban areas, or for terrestrial taxa in the sea or marine taxa on land, have the greatest effect. Automated filtering can help in identifying problematic records, but requires customization of which tests and thresholds should be applied to the taxonomic group and geographic area under focus. Our results stress the importance of thorough recording and exploration of the meta-data associated with species records for biodiversity research.
Resprouting is a plant persistence strategy in response to disturbance or stressful environmental conditions. Resprouters can dominate in stressful environments such as tropical dry forests (TDFs), ...but our knowledge of resprouting in TDFs is limited. Here, using a dataset of forest inventories in 16 TDF fragments (covering 15,642 trees and 321 species), we investigated patterns of resprouting in ecosystems subject to substantial seasonal water stress. We focused on two resprouting metrics: the proportion of trees that are multistemmed (resprouting frequency) and the number of stems per tree. In addition, we investigated the relative importance of environmental factors, taxonomic identity, and evolutionary history in resprouting response. Taxa with low to medium resprouting frequencies (17.19%–40.2%) are the most prevalent in TDF, compared to non‐resprouters and high‐frequency resprouters. Overall, resprouting ability appears to be an intrinsic trait that varies in response to environmental conditions but only within a range constrained by taxonomic identity. However, we found no phylogenetic signal above the genus level for any resprouting variables. Thus, the variation in resprouting across TDF lineages likely has been shaped by divergence between closely related taxa and convergence between distantly related ones, reflecting the specific environmental and disturbance factors to which they have been subjected.
Resprouting is a common ecological strategy in trees in tropical dry forest (TDF).
Resprouting by trees is a very variable ecological strategy.
The patterns of resprouting in TDF is mainly conditioned by taxonomic identify, but not present phylogenetical structure.
Global patterns of species and evolutionary diversity in plants are primarily determined by a temperature gradient, but precipitation gradients may be more important within the tropics, where plant ...species richness is positively associated with the amount of rainfall. The impact of precipitation on the distribution of evolutionary diversity, however, is largely unexplored. Here we detail how evolutionary diversity varies along precipitation gradients by bringing together a comprehensive database on the composition of angiosperm tree communities across lowland tropical South America (2,025 inventories from wet to arid biomes), and a new, large-scale phylogenetic hypothesis for the genera that occur in these ecosystems. We find a marked reduction in the evolutionary diversity of communities at low precipitation. However, unlike species richness, evolutionary diversity does not continually increase with rainfall. Rather, our results show that the greatest evolutionary diversity is found in intermediate precipitation regimes, and that there is a decline in evolutionary diversity above 1,490 mm of mean annual rainfall. If conservation is to prioritise evolutionary diversity, areas of intermediate precipitation that are found in the South American 'arc of deforestation', but which have been neglected in the design of protected area networks in the tropics, merit increased conservation attention.
Thoracic limbs are extremely versatile and exhibit informative characteristics about habits of the Carnivora order in the wild. Despite this relevance, comparative studies with quantitative variables ...on thoracic limb muscles are still scarce in carnivorans. The aims of this study were to measure the mass of the intrinsic muscles of the thoracic limb of neotropical species of the Carnivora order and to establish comparative conjectures. For this purpose, 39 thoracic limbs of 10 neotropical carnivorans species were dissected. The mass of each muscle was measured on a digital scale, muscles were grouped by function, and the mass average percentage that each functional group of muscles occupied in the thoracic limb was calculated. The data of the present study was added to that available in the literature for 22 other carnivoran species. Three groups of species were considered: Canidae, Musteloidea, and Feliformia. Comparatively, the eight canid species included in this analyses concentrate muscle mass proximally in the thoracic limb to prioritize essential cursoriality. The nine musteloids had more muscle mass in the distal muscles due to the demand for versatility and manual strength, and the 14 Feliformia species exhibited an intermediate trend. The analysis of clusters revealed a great overlap of the percentage distribution of muscle mass with the phylogeny previously established for carnivorans. It could be verified that the distribution of muscle masses meets the demand of the locomotor habits of the species up to a certain level, from which phylogeny begins to limit morphological adaptations.
Resumo
Os membros torácicos são extremamente versáteis e exibem características informativas sobre os hábitos das espécies da ordem Carnivora em vida livre. A despeito desta relevência, estudos comparativos com variéveis quantitativas dos músculos do membro torácico são escassos em carnívoros. Os objetivos deste estudo foram aferir a massa dos músculos intrínsecos do membro torácico de espécies neotropicais da ordem Carnivora e estabelecer conjecturas comparativas. Para este fim, foram dissecados 39 membros torácicos de dez espécies de carnívoros neotropicais. A massa de cada músculo foi mensurada em uma balança digital, os músculos foram agrupados por função e calculou‐se a massa percentual média a que cada grupo funcional de músculos correspondia no membro torácico. Os dados do presente estudo foram analisados conjuntamente às informações disponíveis na literatura para outras 22 espécies da ordem Carnivora. Três grupos de espécies foram considerados: Canidae, Musteloidea e Feliformia. Comparativamente, as oito espécies de canídeos incluídas nesta análise demonstraram concentração de massa muscular mais proximalmente no membro torácico em razão dos hábitos essencialmente cursoriais. As nove espécies da superfamília Musteloidea exibiram mais massa nos músculos distais devido à maior demanda por versatilidade e força manual. As 14 espécies da subordem Feliformia apresentaram um padrão intermediário. A análise de clusters revelou nítida sobreposição entre o percentual de distribuição da massa muscular com a filogenia previamente estabelecida para a ordem Carnivora. Verificou‐se que a distribuição da massa dos músculos atende à demanda dos hábitos locomotores das espécies até um certo nível, a partir do qual a filogenia começa a limitar as adaptações morfológicas.
•Site-effect induce changes on tree allometry along studied environmental gradient.•Soil properties have significant effect on tree height, volume and bark thickness.•Climate significantly influence ...height-diameter relationship and tree volume.•Bark thickness was not associated with climate across studied environmental gradient.
Tree allometric models are generally developed at local scales and thus potentially biased when used for different locations and at broader spatial scales. Because allometric relationships vary with forest structure, climatic conditions and edaphic properties, one potential way to address this issue and consistently estimate tree allometry, may involve including new explanatory variables into allometric models. Here, using an extensive dataset of 566 trees widely distributed over Rio de Janeiro state, Brazil, we investigated the influence of stand structure, climate, soil fertility and texture in tree allometry (bark thickness, height, and stem volume) in hyperdiverse and structurally complex Atlantic Forest. Water stress, soil texture and to a lesser extent basal area, soil fertility and precipitation, were strong predictors of tree height and volume. Wetter forests with richer soils support higher-statured trees with greater woody volume, whilst drier environments with moderate to low nutrient availability are associated with small-statured and low tree volume. In contrast, bark thickness was solely determined by soil fertility and ph. Negligible relationship between bark thickness and climatic variables is likely associated with our studied gradient that did not encompass dry forests that are adapted to frequent and intense fires, and where bark investment to stem protection ensures survival. These findings suggest that more appropriate approach to reliably estimate tree height, volume and bark thickness at regional and landscape scale, should incorporate environmental descriptors that are strongly associated with forest structure.
Sepsis-induced organ failure is characterized by a massive inflammatory response and oxidative stress. Acute kidney injury (AKI) occurs in approximately half of patients in septic shock, and the ...mortality associated with sepsis-induced AKI is unacceptably high. Klotho is a protein expressed by renal cells and has anti-senescence properties. Klotho has also been shown to protect the kidneys in ischemia-reperfusion injury and to have antioxidant properties. To analyze the role of Klotho in sepsis-related organ dysfunction and AKI, we used a cecal ligation and puncture (CLP) model of sepsis in heterozygous Klotho-haploinsufficient mice and their wild-type littermates (CLP- Kl/+ and CLP-WT mice, respectively). In comparison with the CLP-WT mice, CLP- Kl/+ mice showed lower survival, impaired renal function, impaired hepatic function, greater oxidative stress, upregulation of inflammatory pathways (at the systemic and kidney tissue levels), and increased NF-κB activation. It is noteworthy that CLP- Kl/+ mice also showed lower heart-rate variability, less sympathetic activity, impaired baroreflex sensitivity to sodium nitroprusside, and a blunted blood pressure response to phenylephrine. We also demonstrated that sepsis creates a state of acute Klotho deficiency. Given that low Klotho expression exacerbates sepsis and multiple organ dysfunction, Klotho might play a protective role in sepsis, especially in elderly individuals in whom Klotho expression is naturally reduced.
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.
The maned sloth (
) is an endemic and endangered species of two Brazilian states, with much unknown biological information needed to direct conservation actions. Other sloth species have been studied ...regarding anesthesia; however, there is a lack of anesthesia research for the maned sloth. Anesthetic data were collected from 12 free-range maned sloths that were immobilized for a field examination. Individuals were anesthetized using a combination of ketamine (4.0 mg/kg) and medetomidine (0.03 mg/kg), and antagonized with atipamezole (0.1 mg/kg). Time to induction and recovery were recorded and compared with sex and age classes. After the induction and until antagonist administration, physiological parameters (rectal temperature, heart rate, respiratory rate, and oxygen saturation) were recorded every 10 min during anesthesia and were statistically evaluated over time. Induction was fast (3.21 ± 0.76), but recovery was longer (113.3 ± 18) when compared to other studies. Induction and recovery times were not different across sex or age classes. Rectal temperature, heart rate, and oxygen saturation remained stable throughout the procedure. Respiratory rate significantly decreased over time, from 18.25 ± 7.03 to 13.17 ± 3.66 movements per minute. Our results indicate that the described combination of ketamine and medetomidine is a safe and effective choice for anesthesia of maned sloths.
To evaluate the association between abuse of and dependence on different psychoactive substances and the presence of anxiety disorders in a sample of young adults from a city in southern Brazil.
...Between 2007 and 2009, we carried out a cross-sectional, population-based study of individuals aged 18-24 years who lived in Pelotas, a city in southern Brazil. We evaluated anxiety disorders using the Mini International Neuropsychiatric Interview 5.0 (MINI), and use of psychoactive substances with the Alcohol, Smoking, and Substance Involvement Screening Test (ASSIST 2.0/0MS). We used Fisher's exact test for univariate analysis, and Poisson regression models with robust variance for multivariable analysis.
The sample consisted of 1,560 young adults. The overall prevalence of abuse/dependence was 26.9% for alcohol, 24.9% for tobacco, and 7.3% for illicit substances. Individuals with agoraphobia had a 32% higher prevalence of tobacco abuse/dependence (prevalence ratio PR = 1.32 95%CI 1.01-1.74). Individuals with posttraumatic stress disorder (PTSD) or generalized anxiety disorder (GAD) had a 2.41-fold (95%CI 1.22-4.77) and 1.76-fold (95%CI 1.00-3.11) higher prevalence of illicit substance abuse/dependence, respectively.
In this population-based sample, we found associations between GAD, PTSD, and increased prevalence of illicit substance abuse/dependence. In addition, individuals with agoraphobia seem to have increased tobacco abuse/dependence.
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