Evolutionary heritage shapes tree distributions along an Amazon-to-Andes elevation gradient

Understanding how evolutionary constraints shape the elevational distributions of tree lineages provides valuable insight into the future of tropical montane forests under global change. With narrow elevational ranges, high taxonomic turnover, frequent habitat specialization, and exceptional levels of endemism, tropical montane forests and trees are predicted to be highly sensitive to environmental change. Using plot census data from a gradient traversing > 3,000 m in elevation on the Amazonian flank of the Peruvian Andes, we employ phylogenetic approaches to assess the influence of evolutionary heritage on distribution trends of trees at the genus‐level. We find that closely related lineages tend to occur at similar mean elevations, with sister genera pairs occurring a mean 254 m in elevation closer to each other than the mean elevational difference between non‐sister genera pairs. We also demonstrate phylogenetic clustering both above and below 1,750 m a.s.l, corresponding roughly to the cloud‐base ecotone. Belying these general trends, some lineages occur across many different elevations. However, these highly plastic lineages are not phylogenetically clustered. Overall, our findings suggest that tropical montane forests are home to unique tree lineage diversity, constrained by their evolutionary heritage and vulnerable to substantial losses under environmental changes, such as rising temperatures or an upward shift of the cloud‐base.National Science Foundation, Grant/Award Number: NSF DEB LTREB 1754647 and NSF DEB LTREB 1754664; Natural Environment Research Council, Grant/Award Number: NE/G018278/1 and NE/L002558/1; Australian Research Council, Grant/Award Number: DP17010409

Propuesta de un programa de auditoría a los sistemas de información

  Los cambios que ocurren actualmente a nivel mundial, tales como los avances económicos, tecnológicos y las crecientes exigencias de los servicios que prestarán las organizaciones que ejercen la auditoría hacen que se necesiten cada vez más herramientas de apoyo específicas para evaluar los sistemas de información en general. En este contexto se plantea como objetivo general de esta investigación proponer un programa de auditoría a los sistemas de información adecuado a las características del sistema empresarial cubano que permita el desarrollo efectivo de acciones de control de este tipo, ya que existen limitadas experiencias en este ámbito y generalmente con poco nivel de integración. Para su elaboración se utilizaron diferentes técnicas y herramientas tales como el diagrama causa-efecto, técnicas de auditoría y método de expertos, este último por la imperiosa necesidad de considerar la experiencia acumulada de auditores e informáticos. Palabras clave: auditoría, programas, sistemas de información.   ABSTRACT    The current global changes, such as economic and technological developments and the increasing requirements of the services provided by the organizations that perform the audit, mean that more and more specific support tools are needed to evaluate the information systems in general. In this context, it is proposed as a general objective of this research to propose an audit program to the information systems appropriate to the characteristics of the Cuban business system that allows the effective development of control actions of this type, since there are limited experiences in this area and generally with little level of integration. Different techniques and tools, such as the cause-effect diagram, audit techniques and expert method, were used to elaborate the latter due to the imperative need to consider the accumulated experience of auditors and computer scientists.   Key words: audit, programs, information systems

Capacidad antioxidante: conceptos, métodos de cuantificación y su aplicación en la caracterización de frutos tropicales y productos derivados

Antioxidant capacity has become a widely demanded feature in actually foods. The knowledge of the molecules that contribute this activity, as well as the natural foods where they can be found, provides information for the correct use of these important substances. However, even today, methods for measuring antioxidant capacity in vitro remain poorly unified. Although there are at least three universally used methods, the units in which the results are expressed are heterogeneous, which makes accurate comparison between samples of a similar nature somewhat difficult. This review includes a review of basic aspects of antioxidant capacity, with an emphasis on the molecules responsible for such activity and the methods available to quantify it. Additionally, given that foods of plant origin are the main natural source of antioxidant compounds, a brief review is made of studies that quantify the antioxidant capacity of tropical fruits and their products or co-products.La capacidad antioxidante se ha convertido en una característica ampliamente demandada en los alimentos contemporáneos. El conocimiento de las moléculas que imparten esta actividad, así como los alimentos donde pueden encontrarse de manera natural, aporta información para el correcto aprovechamiento de estas importantes sustancias. Sin embargo, aún hoy día, los métodos para medir la capacidad antioxidante in vitro siguen poco unificados. Aunque existen al menos tres métodos universalmente utilizados, las unidades en la que se expresan los resultados son heterogéneas, lo que dificulta un poco la comparación certera entre muestras de naturaleza similar. El objetivo del presente artículo fue realizar una revisión sobre aspectos fundamentales de la capacidad antioxidante, con énfasis en las moléculas responsables de tal actividad y los métodos disponibles para cuantificarla. Adicionalmente, dado que los alimentos de origen vegetal son la principal fuente natural de compuestos antioxidantes, se incluyen reportes de estudios que cuantifican la capacidad antioxidante de frutos tropicales y de productos o coproductos de éstos

Evolutionary diversity peaks at mid-elevations along an Amazon-to-Andes elevation gradient

Elevation gradients present enigmatic diversity patterns, with trends often dependent on the dimension of diversity considered. However, focus is often on patterns of taxonomic diversity and interactions between diversity gradients and evolutionary factors, such as lineage age, are poorly understood. We combine forest census data with a genus level phylogeny representing tree ferns, gymnosperms, angiosperms, and an evolutionary depth of 382 million years, to investigate taxonomic and evolutionary diversity patterns across a long tropical montane forest elevation gradient on the Amazonian flank of the Peruvian Andes. We find that evolutionary diversity peaks at mid-elevations and contrasts with taxonomic richness, which is invariant from low to mid-elevation, but then decreases with elevation. We suggest that this trend interacts with variation in the evolutionary ages of lineages across elevation, with contrasting distribution trends between younger and older lineages. For example, while 53% of young lineages (originated by 10 million years ago) occur only below ∼1,750 m asl, just 13% of old lineages (originated by 110 million years ago) are restricted to below ∼1,750 m asl. Overall our results support an Environmental Crossroads hypothesis, whereby a mid-gradient mingling of distinct floras creates an evolutionary diversity in mid-elevation Andean forests that rivals that of the Amazonian lowlands

Modern pollen rain predicts shifts in plant trait composition but not plant diversity along the Andes–Amazon elevational gradient

This is the final version. Available on open access from Wiley via the DOI in this record. Aims: Terrestrial ecosystems are changing in biodiversity, species composition and functional trait composition. To understand the underlying causes of these changes and predict the long-term resilience of the ecosystem to withstand future disturbances, we can evaluate changes in diversity and composition from fossil pollen records. Although diversity can be well estimated from pollen in temperate ecosystems, this is less clear for the hyperdiverse tropics. Moreover, it remains unknown whether functional composition of plant assemblages can be accurately predicted from pollen assemblage composition. Here, we evaluate how community-weighted mean (CWM) traits and diversity indices change along elevation. Location: Amazon–Andes elevation gradient in Peru. Methods: We used 82 modern pollen samples and 59 vegetation plots along the elevation gradient, and calculated CWM traits and diversity indices for each pollen sample and vegetation plot. We also quantified the degree to which taxa are over- or underrepresented by their pollen, by dividing the relative pollen abundance by the relative basal area abundance in the nearby vegetation survey plots (i.e. the R-rel values). Results: We found that CWM wood density increased, and CWM adult height and leaf area decreased with elevation. This change was well predicted by pollen assemblages, indicating that CWM trait–environment relationships based on pollen abundance data provide meaningful results. Diversity (richness, Shannon and Simpson) decreased with elevation for vegetation plots, but these trends could not be observed from pollen assemblages. Conclusions: Our results demonstrate that more research is needed to develop methods that lead to accurate diversity estimates from pollen data in these tropical ecosystems, but that CWM traits can be calculated from pollen data to assess spatial shifts in functional composition. This opens opportunities to calculate CWM traits from fossil pollen data sets in the tropics, with broad implications for improving our understanding and predictions of forest dynamics, functioning and resilience through time.Nederlandse Organisatie voor Wetenschappelijk Onderzoe

In silico Analyses of Immune System Protein Interactome Network, Single-Cell RNA Sequencing of Human Tissues, and Artificial Neural Networks Reveal Potential Therapeutic Targets for Drug Repurposing Against COVID-19

Background: There is pressing urgency to identify therapeutic targets and drugs that allow treating COVID-19 patients effectively.Methods: We performed in silico analyses of immune system protein interactome network, single-cell RNA sequencing of human tissues, and artificial neural networks to reveal potential therapeutic targets for drug repurposing against COVID-19.Results: We screened 1,584 high-confidence immune system proteins in ACE2 and TMPRSS2 co-expressing cells, finding 25 potential therapeutic targets significantly overexpressed in nasal goblet secretory cells, lung type II pneumocytes, and ileal absorptive enterocytes of patients with several immunopathologies. Then, we performed fully connected deep neural networks to find the best multitask classification model to predict the activity of 10,672 drugs, obtaining several approved drugs, compounds under investigation, and experimental compounds with the highest area under the receiver operating characteristics.Conclusion: After being effectively analyzed in clinical trials, these drugs can be considered for treatment of severe COVID-19 patients. Scripts can be downloaded at

Large-scale patterns of turnover and basal area change in Andean forests

General patterns of forest dynamics and productivity in the Andes Mountains are poorly characterized. Here we present the first large-scale study of Andean forest dynamics using a set of 63 permanent forest plots assembled over the past two decades. In the North-Central Andes tree turnover (mortality and recruitment) and tree growth declined with increasing elevation and decreasing temperature. In addition, basal area increased in Lower Montane Moist Forests but did not change in Higher Montane Humid Forests. However, at higher elevations the lack of net basal area change and excess of mortality over recruitment suggests negative environmental impacts. In North-Western Argentina, forest dynamics appear to be influenced by land use history in addition to environmental variation. Taken together, our results indicate that combinations of abiotic and biotic factors that vary across elevation gradients are important determinants of tree turnover and productivity in the Andes. More extensive and longer-term monitoring and analyses of forest dynamics in permanent plots will be necessary to understand how demographic processes and woody biomass are responding to changing environmental conditions along elevation gradients through this century