Repositorio Digital Ikiam (Univ. Regional Amazónica)
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Altitude and life-history shape the evolution of Heliconius wings
Get PDFPhenotypic divergence between closely related species has long interested biologists. Taxa that inhabit a range of environments and have diverse natural histories can help understand how selection drives phenotypic divergence. In butterflies, wing color patterns have been extensively studied but diversity in wing shape and size is less well understood. Here, we assess the relative importance of phylogenetic relatedness, natural history, and habitat on shaping wing morphology in a large dataset of over 3500 individuals, representing 13 Heliconius species from across the Neotropics. We find that both larval and adult behavioral ecology correlate with patterns of wing sexual dimorphism and adult size. Species with solitary larvae have larger adult males, in contrast to gregarious Heliconius species, and indeed most Lepidoptera, where females are larger. Species in the pupal-mating clade are smaller than those in the adult-mating clade. Interestingly, we find that high-altitude species tend to have rounder wings and, in one of the two major Heliconius clades, are also bigger than their lowland relatives. Furthermore, within two widespread species, we find that high-altitude populations also have rounder wings. Thus, we reveal novel adaptive wing morphological divergence among Heliconius species beyond that imposed by natural selection on aposematic wing coloration
Experiencias Latino Americanas en la democratización de los biodigestores: Aportes a Ecuador
Get PDFEl objetivo de este documento es presentar las experiencias internacionales,
principalmente latinoamericanas, respecto las estrategias de democratización
de los biodigestores dirigidos a pequeños y medianos productores. Inicialmente,
se presentarán los biodigestores, su funcionamiento, productos y tipos de
sistemas. Posteriormente, se explicará en qué se basan los programas
nacionales de biogás y cómo funcionan estos. Consecutivamente, se presentará
la única experiencia latinoamericana de este tipo de programas que fue en
Nicaragua y se complementará con otras iniciativas de democratización de los
biodigestores fuera del contexto de los programas nacionales de biogás, en
países como México, Costa Rica, Colombia y Bolivia. Finalmente, se pondrán
a consideración algunos aspectos específicos de los programas nacionales
de biogás y experiencias regionales, para evaluar el contexto ecuatoriano y
sus potencialidades para el desarrollo de una estrategia de democratización
de los biodigestores entre pequeños y medianos productores agropecuario
Priorities and Interactions of Sustainable Development Goals (SDGs) with Focus on Wetlands
Get PDFWetlands are often vital physical and social components of a country’s natural capital, as well as providers of ecosystem services to local and national communities. We performed a network analysis to prioritize Sustainable Development Goal (SDG) targets for sustainable development in iconic wetlands and wetlandscapes around the world. The analysis was based on the information and perceptions on 45 wetlandscapes worldwide by 49 wetland researchers of the Global Wetland Ecohydrological Network (GWEN). We identified three 2030 Agenda targets of high priority across the wetlandscapes needed to achieve sustainable development: Target 6.3—“Improve water quality”; 2.4—“Sustainable food production”; and 12.2—“Sustainable management of resources”. Moreover, we found specific feedback mechanisms and synergies between SDG targets in the context of wetlands. The most consistent reinforcing interactions were the influence of Target 12.2 on 8.4—“Efficient resource consumption”; and that of Target 6.3 on 12.2. The wetlandscapes could be differentiated in four bundles of distinctive priority SDG-targets: “Basic human needs”, “Sustainable tourism”, “Environmental impact in urban wetlands”, and “Improving and conserving environment”. In general, we find that the SDG groups, targets, and interactions stress that maintaining good water quality and a “wise use” of wetlandscapes are vital to attaining sustainable development within these sensitive ecosystems.Stockholm Resilience Centre - Stockholm Universit
Combined effects of temperature and copper on oxygen consumption and antioxidant responses in the mudflat fiddler crab Minuca rapax (Brachyura, Ocypodidae)
Get PDFThis study investigates the combined effects of waterborne copper exposure and acute temperature change on oxygen consumption and the oxidative stress biomarkers, glutathione S-transferase (GST) and glutathione peroxidase (GPx), in the gills and hepatopancreas of the fiddler crab Minuca rapax. Crabs held at 25 °C were acclimated to 0 (control), 50, 250 or 500 μg Cu L−1 for 21 days, and were then subjected to 15, 25 and 35 °C for 24 h. Aerial oxygen consumption rates of crabs in copper free media increased with increasing temperature from 15 to 35 °C, Q10 values reaching ≈3. Crabs exposed to increasing copper concentrations exhibited variable responses, Q10 values falling to ≈1.5. Copper had no effect on oxygen consumption at 25 °C. However, at 35 °C, rates decreased in a clear concentration-response manner in the copper exposed crabs, revealing impaired aerobic capability. At 15 °C, oxygen consumption rates increased with copper concentration, except for a decrease at 500 μg Cu L−1. Gill GST activity was ≈2-fold that of the hepatopancreas, while hepatopancreas GPx activity was 3-fold that of the gills. Gill GST activities were reduced by copper exposure only at 25 °C while hepatopancreas GST activities were altered by copper at all temperatures. Hepatopancreas GST and GPx activities increased in crabs exposed to copper at 35 °C, revealing oxidative stress induction. Hepatopancreas GST and GPx activities were reduced in copper exposed crabs at 15 °C, suggesting a diminished capability to mitigate the effects of copper exposure at low temperature. These findings reveal that copper exposure increases oxygen consumption at low temperatures but decreases consumption at high temperature. Hepatopancreas GPx activities decreased at low temperature and increased at high temperature. These novel findings demonstrate that the interaction between copper exposure and temperature should be considered when evaluating biomarker activities in semi-terrestrial crabs
Biodigestores Tubulares: Guía de diseño y Manual de instalación
Get PDFEspero que este libro sirva para que más personas puedan introducirse al mundo de los biodigestores, y los que ya estaban en este mundo, les pueda aportar alguna nueva idea.
Espero haber logrado el objetivo de hacer accesible una metodología rigurosa de diseño de biodigestores tubulares, de modo que cualquiera que sea capaz de manejar una calculadora, pueda hacer sus propios diseños. El manual de instalación es solo uno más, pues ya existen otros libre por internet que recomiendo consultar, pues siempre hay otras formas de explicar cada proceso y algunas ideas diferentes.
Espero también, que se use con responsabilidad la información aportada en este libro. Saber diseñar e instalar biodigestores no es garantía de lograr procesos sostenibles de democratización de la tecnología. Lo que se muestra en este libro es principalmente la parte técnica, pero la democratización de la tecnología es mucho más que eso. Al final, los usuarios, las familias campesinas, son el centro y por ello es necesario tener muy claro los procesos sociales necesarios, justos y participativos, para democratizar la tecnología. Por favor, si vas a comenzar a diseñar e instalar biodigestores, comienza de forma piloto, para que te sirva a ti mismo de aprendizaje, y no generes expectativas en otros que no estés seguro de poder cumplir. Poco a poco. Aprende de otras experiencias, únete a otros en este proceso, y comparte tus aciertos y errores
Discovering floristic and geoecological gradients across Amazonia
Get PDFAim: To map and interpret floristic and geoecological patterns across the Amazon basin by combining extensive field data with basin-wide Landsat imagery and climatic data Location: Amazonia Taxon: Ground truth data on ferns and lycophytes; remote sensing results reflect forest canopy properties Methods: We used field plot data to assess main ecological gradients across Amazonia and to relate floristic ordination axes to soil base cation concentration, CHELSA climatic variables and reflectance values from a basin-wide Landsat image composite with generalized linear models (GLM). Ordination axes were then predicted across all Amazonia using Landsat and CHELSA, and a regional subdivision was obtained using k-medoid classification. Results: The primary floristic gradient was strongly related to base cation concentration in the soil, and the secondary gradient to climatic variables. The Landsat image composite revealed a tapestry of broad-scale variation in canopy reflectance characteristics across Amazonia. Ordination axis scores predicted using Landsat and CHELSA variables produced spatial patterns consistent with existing knowledge on soils, geology and vegetation, but also suggested new floristic patterns. The clearest dichotomy was between central Amazonia and the peripheral areas, and the available data supported a classification into at least eight subregions. Main conclusions Landsat data are capable of predicting soil-related species compositional patterns of understory ferns and lycophytes across the Amazon basin with surprisingly high accuracy. Although the exact floristic relationships may differ among plant groups, the observed ecological gradients must be relevant for other plants as well, since surface reflectance recorded by satellites is mostly influenced by the tree canopy. This opens exciting prospects for species distribution modelling, conservation planning, and biogeographical and ecological studies on Amazonian biota. Our maps provide a preliminary geoecological subdivision of Amazonia that can now be tested and refined using field data of other plant groups and from hitherto unsampled areas
Perceptions of a curriculum vitae clinic for conservation science students
Get PDFWe led a curriculum vitae (CV) clinic aimed at student participants attending the
28th International Congress for Conservation Biology (ICCB 2017) in Cartagena, Colombia. The CV Clinic was a pilot program consisting of resources to assist with developing an effective CV and involving preconference and at-conference reviews of student attendees' CVs. Here, we explore our experiences in organizing the CV Clinic as well as nonparticipant and participant perceptions of the clinic. We used an online standardized interview form to gather qualitative data on nonparticipant and participant perceptions of the CV Clinic, and to explore how such a CV Clinic program could best align with student needs. Most respondents who submitted their CV for review ahead of ICCB 2017 (n = 9) found the template and guidance useful. Half of the respondents who did not participate in the CV Clinic perceived the clinic as duplicating services provided by their academic institutions. Both par- ticipant and nonparticipant respondents perceived value in such a CV Clinic, but also believed that adjustments could be made to make the CV review part of a broader professional development program lead by Society for Conservation Biol- ogy (SCB). Key lessons learned from the CV Clinic include the need to: (a) document and evaluate professional development initiatives within SCB; (b) better understand and account for the diversity of student needs before program creation; and (c) pilot and evaluate appropriateness of different locations, fre- quency, and duration of professional development programs.John Wiley & Son
Embryogenic competence of microspores is associated with their ability to form a callosic, osmoprotective subintinal layer
Get PDFMicrospore embryogenesis is an experimental morphogenic pathway with important applications in basic research and applied plant breeding, but its genetic, cellular, and molecular bases are poorly understood. We applied a multi- disciplinary approach using confocal and electron microscopy, detection of Ca2+, callose, and cellulose, treatments with caffeine, digitonin, and endosidin7, morphometry, qPCR, osmometry, and viability assays in order to study the dynamics of cell wall formation during embryogenesis induction in a high-response rapeseed (Brassica napus) line and two recalcitrant rapeseed and eggplant (Solanum melongena) lines. Formation of a callose-rich subintinal layer (SL) was common to microspore embryogenesis in the different genotypes. However, this process was directly related to embryogenic response, being greater in high-response genotypes. A link could be established between Ca2+ influx, abnormal callose/cellulose deposition, and the genotype-specific embryogenic competence. Callose deposition in inner walls and SLs are independent processes, regulated by different callose synthases. Viability and control of internal osmolality are also related to SL formation. In summary, we identified one of the causes of recalcitrance to embryogenesis induction: a reduced or absent protective SL. In responding genotypes, SLs are markers for changes in cell fate and serve as osmoprotective barriers to increase viability in imbalanced in vitro environments. Genotype- specific differences relate to different responses against abiotic (heat/osmotic) stresses.Oxford University Pres
Structure−Activity Relationships of Pentacyclic Triterpenoids as Inhibitors of Cyclooxygenase and Lipoxygenase Enzymes
Get PDFPentacyclic triterpenes may be active agentsand provide a rich natural resource of promising compoundsfor drug development. The inhibitory activities of 29 naturaloleanane and ursane pentacyclic triterpenes were evaluatedagainst four major enzymes involved in the inflammatoryprocess: 5-LOX, 15-LOX-2, COX-1, and COX-2. It was foundthat 3-O-acetyl-β-boswellic acid potently inhibited human 15-LOX-2 (IC50= 12.2±0.47μM). Analysis of the structure−activity relationships revealed that the presence of a hydroxygroup at position 24 was beneficial in terms of both 5-LOXand COX-1 inhibition. Notably, the introduction of acarboxylic acid group at position 30 was important for dual5-LOX/COX inhibitory activity; furthermore, its combination with a carbonyl group at C-11 considerably increased 5-LOXinhibition. Also, the presence of anα-hydroxy group at C-2 or a carboxylic acid group at C-23 markedly suppressed the 5-LOXactivity. The presentfindings reveal that the types and configurations of polar moieties at positions C-2, -3, -11, -24, and -30 areimportant structural aspects of pentacyclic triterpenes for their potential as anti-inflammatory lead compounds
Skin secretion transcriptome remains in chromatographic fractions suitable for molecular cloning
Get PDFTraditional sources of mRNA for molecular cloning on amphibian skin secretion studies have been the frog's skin and skin secretions. Here, we demonstrate that mRNA isolated from chromatographic fractions of skin secretions is amenable for molecular cloning assays. We identified precursor sequences of the Arg0, Trp5, Leu8-bradykinin and six antimicrobial peptides of Pelophylax esculentus (Ranidae). These results show that both transcriptomic and peptidomic analyses can be performed with a single sample reducing in half the amount of starting skin secretion required. This is a significant advantage when working with endangered or very rare amphibian species, where minimal samples are available