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Libro de ponencias: Primer Congreso Virtual Latinoamericano Mitos y Realidades de la Investigación Científica
No full textReúne las veintiocho ponencias fundamentadas a partir de investigaciones, experiencias profesionales y vivencias académicas de un grupo de colegas pertenecientes a varios países de Latinoamérica que aportaron a la reflexión crítica sobre el quehacer investigativo
Competencias esenciales del investigador científico del siglo XXI
No full textRealiza un recorrido teórico, metodológico y sistemático sobre las áreas más importantes que deben tomarse en consideración cuando hablamos del perfil de un investigador; inicia con una disertación acerca de los conceptos básicos asociados a los significados de la competencia investigativa, el rol de la epistemología como fuente de análisis del conocimiento y no menos importante una reflexión acerca de las principales corrientes filosóficas que han sustentado la producción de conocimientos a lo largo de la historia de la humanidad; sentando las bases para la comprensión de la investigación como un proceso cargado de sentido y contexto para quien lo lleva a cabo
Acylpolyamine mygalin as a TLR4 antagonist based on molecular docking and in vitro analyses
No full textToll-like receptors (TLRs) are transmembrane proteins that are key regulators of innate and adaptive immune responses, particularly TLR4, and they have been identified as potential drug targets for the treatment of disease. Several low-molecular-weight compounds are being considered as new drug targets for various applications, including as immune modulators. Mygalin, a 417 Da synthetic bis-acylpolyamine, is an analog of spermidine that has microbicidal activity. In this study, we investigated the effect of mygalin on the innate immune response based on a virtual screening (VS) and molecular docking analysis. Bone marrow-derived macrophages and the cell lines J774A.1 and RAW 264.7 stimulated with lipopolysaccharide (LPS) were used to confirm the data obtained in silico. Virtual screening and molecular docking suggested that mygalin binds to TLR4 via the protein myeloid differentiation factor 2 (MD-2) and LPS. Macrophages stimulated by mygalin plus LPS showed suppressed gene expression of tumor necrosis factor (TNF-α), interleukine 6 (IL-6), cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS), as well as inhibition of signaling protein p65 of the nuclear factor κB (NF-κB), resulting in decreased production of nitric oxide (NO) and TNF-α. These results indicate that mygalin has anti-inflammatory potential, being an attractive option to be explored. In addition, we reinforce the importance of virtual screening analysis to assist in the discovery of new drugs. © 2020 by the authors. Licensee MDPI, Basel, Switzerland.Fondo Nacional de Desarrollo Científico y Tecnológico - Fondecy
Evidence of a large “prehistorical” earthquake during Inca times? New insights from an indigenous chronicle (Cusco, Peru)
No full textA colonial chronicle written by the indigenous Peruvian author Pachacuti Yamqui Salcamaygua ([1613?]) relates a legend of the sudden appearance of a huge animal – kilometres in length and approximately 4 m in width – and described as the Andean snake-like deity amaru. Pachacuti Yamqui alleged that this fantastic event occurred on the day that the sovereign Pachacuti Inca Yupanqui's eldest son was born around 1440 CE, and was named “Amaru”. We suggest that the underlying event was an earthquake, and that the propagation of the surface rupture across the landscape resembled a sudden appearance of a snake-like being wriggling over the mountains and leaving an undulating surface trace. The concordance between the snake's route and the layout of a major fault complex above Cusco, as well as several ethnographic testimonies, support this hypothesis. Although little is known about pre-1532 CE seismicity, the current tectonic settings of the Cusco area point to seismic awareness of the Incas (ca. 1300–1532 CE). Independent results from architectural and paleoseismological fields in the Cusco area corroborate a significant impact of large earthquakes on local societies. In Peru, without pre-Hispanic written sources, the oral folklore and traditions preserved in Spanish chronicles offer a relevant, but still underexploited resource for identifying paleo-extreme events. Combining multidisciplinary geomorphic observations, archaeological evidence and historical sources, we revisit this legendary episode and its possible implications. © 2020 Elsevier LtdConsejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Validation of microbial source tracking markers for the attribution of fecal contamination in indoor-household environments of the Peruvian Amazon
No full textThe performance of eight microbial source tracking (MST) markers was evaluated in a low-resource, tropical community located in Iquitos, Peru. Fecal samples from humans, dogs, cats, rats, goats, buffalos, guinea-pigs, chickens, ducks, pigeons, and parrots were collected (n = 117). All samples were tested with human (BacHum, HF183-Taqman), dog (BactCan), pig (Pig-2-Bac), and avian (LA35, Av4143, ND5, cytB) markers using quantitative PCR (qPCR). Internal validity metrics were calculated using all animal fecal samples, as well as animal fecal samples contextually relevant for the Peruvian Amazon. Overall, Pig-2-Bac performed best, with 100% sensitivity and 88.5% specificity to detect the correct fecal source. Human-associated markers showed a sensitivity of 80.0% and 76.7%, and specificity of 66.2% and 67.6%. When limiting the analysis to contextually relevant animal fecal samples for the Peruvian Amazon, Av143 surpassed cytB with 95.7% sensitivity and 81.8% specificity. BactCan demonstrated 100% sensitivity and 47.4% specificity. The gene copy number detected by BacHum and HF183-Taqman were positively correlated (Pearson's correlation coefficient: 0.785), as well as avian markers cytB with Av4143 (Pearson's correlation coefficient: 0.508) and nd5 (Pearson's correlation coefficient: 0.949). These findings suggest that markers such as Av4143, Pig2Bac, cytb and BacHum have acceptable performance to be impactful in source attribution studies for zoonotic enteric disease transmission in this and similar low-resource communities. © 2020 The AuthorsFondo Nacional de Desarrollo Científico y Tecnológico - Fondecy
Current thermal state of permafrost in the southern Peruvian Andes and potential impact from El Niño–Southern Oscillation (ENSO)
No full textTropical high-mountain permafrost has a unique thermal regime due to its exposure to strong solar radiation and to rough surface snow morphology, which reduce ground heat transfer from the surface. Latent heat transfer and higher albedo that occur during the snow-covered season contribute to positive feedback that supports the presence of permafrost. This preliminary study reports on the thermal state characteristics of tropical mountain permafrost in Peru. This work also evaluates the potential combined impact of the El Niño–Southern Oscillation (ENSO) in the mountain permafrost of the Coropuna and Chachani volcanic complexes, both located at the western edge of the southern Peruvian Altiplano. Temperature monitoring boreholes were established at 5,217 m at Coropuna and 5,331 m at Chachani, and electrical resistivity was surveyed in both sites. This 7-year discontinuous record of permafrost temperature data encompasses historically extreme El Niño/La Niña events. Our results show that the current lower-altitude permafrost boundary (~5,100 m a.s.l.) is critically influenced by the balance of wet and dry seasons: permafrost tends to deplete during drought years. Typical permafrost thickness was 10–20 m and contained ice-rich pore spaces. The presence of permafrost and its thermal resistance depends on ice content and on higher albedo, usually due to: (a) hydrothermal alteration, which transforms the volcanic rocks into surfaces with ideal albedo for permafrost resilience; and (b) sublimation of the snow cover, forming ice-pinnacles named penitentes. © 2020 John Wiley & Sons, Ltd.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Effects of the violation of the equivalence principle at DUNE
No full textA number of different effects of the violation of the equivalence principle (VEP), taken as subleading mechanism of neutrino flavor oscillation, are examined within the framework of the DUNE experiment. We study the possibility of obtaining a misleading neutrino oscillation parameter region caused by our unawareness of VEP. Additionally, we evaluate the impact on the measurement of CP violation and the distinction of neutrino mass hierarchy at DUNE. Besides, limits on VEP for a wide variety of textures of the matrix that connects neutrino gravity eigenstates to flavor eigenstates are imposed. An extra task of our study is to set limits on Hamiltonian added terms considering different energy dependencies (Ed-3, with d=3, 4, 5, 6) that can be associated to the usual Lorentz violating terms defined in the Standard Model extension Hamiltonian. In order to understand our results, approximated analytical three neutrino oscillation probability formulae are derived. © 2020 authors. Published by the American Physical Society.Fondo Nacional de Desarrollo Científico y Tecnológico - Fondecy
Use of rita® temporary immersion system to obtain microtubers of several mashua Tropaeolum tuberosum Ruiz y Pavón morphotypes
No full textBackground. The Temporary Immersion System (TIS) is an effective strategy to obtain quality mashua microtubers through the in vitro propagation of seedlings in a small space and in a short period of time. Objective. Obtain microtubers of 27 mashua morphotypes (Tropaeolum tuberosum) using the TIS-RITA®. Methodology. The seedlings were previously propagated in MS (Murashige & Skoog) solid medium, supplemented with 3% sucrose, at 5.6 pH and 0.7% agar. After fifteen days of cultivation in this medium, the seedlings were transferred to a MS liquid. For the tuberization process, seedlings with an average size of 10 cm were transferred to TIS-RITA® systems for ten weeks, under conditions of complete darkness, at 19 ± 2 ° C, an immersion frequency of 2 minutes every 3 hours in a MS liquid medium supplemented with 8% sucrose and 2 mg.L-1 benzylamino purine (BAP). Results. The best results of microtubers were obtained with different morphotypes, which are respect to i/size, MAC 06A (1.9 cm) and MAC 056 (1.8 cm); ii / fresh weight, MAC 06A (0.2g) and MAC 092 (0.18 g); iii / quantity, MAC 08A (51 units) and MAC 048 (56 units). Implications. TIS-RITA® can be used to obtain quality and virus-free seeds of a wide variety of commercially important crops. Conclusion. The SIT-RITA® based on the intermittent contact of the explants cultivating medium, is an efficient system to obtain mashua microtubers.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Dendroclimatological assessment of Polylepis rodolfo-vasquezii: A novel Polylepis species in the Peru highlands
No full textIn spite of enormous diversity in tree species, dendrochronological records in the tropical Andes are very scarce. Therefore, it is necessary to increase the search for new tree species with high dendrochronological characteristics in the tropical Andes, including the humid Puna of Peru. We present the first tree-ring chronology from Polylepis rodolfo-vasquezii, a recently described tree species in the Central Andes of Peru between 4000 and 4400 m elevation. Fifty trees were sampled in the district of Comas, Peru. After establishing the anatomical characteristics that delimit the annual growth rings, we developed a ring-width chronology by applying conventional dendrochronological techniques. The chronology covers the period 1869–2015 (157 years) and is well replicated from 1920 to present (> 20 samples). The statistics used to evaluate the quality of the chronology indicate that the P. rodolfo-vasquezii has similar values of MS, RBAR and EPS to those shown by other Polylepis spp chronologies. To determine the main climatic factors controlling the growth of P. rodolfo-vasquezii, we compared our chronology with local and regional temperature and precipitation records. Growth season temperature (November to May) seems to be the main climatic factor modulating inter-annual variations in the growth of this species. The sensitivity to inter-annual temperature variations highlights the potential of P. rodolfo-vasquezii to provide climatically sensitive dendrochronological records in the Central Andes. To our knowledge, this is the first tree-ring record in South America displaying significant relationships with temperature over the tropical Atlantic Ocean. © 2020 Elsevier GmbHConsejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Neutralization of the lethal activity from bothrops atrox venom by hyperimune llama serum (Lama glama) [Neutralización de la actividad letal del veneno de serpiente bothrops atrox por suero hiperinmune de llama (Lama glama)]
No full textObjectives: To evaluate the capacity of the hyperimmune llama serum (Lama glama) to neutralize the lethal activity of Bothrops atrox venom in laboratory mice. Materials and methods: Mean lethal dose (LD50 ) was calculated from a Bothrops atrox venom sample pool from Peru. The antibody titers were measured by ELISA assay; and the immune serum neutralization potency was measured by calculating the mean effective dose (ED50) during the immunization period. Results: The venom’s LD50 was 3.96 ?g/g; similar to what was found in other studies about Bothrops atrox carried out in Peru. The titers of antibodies against the venom increased rapidly in the llama, demonstrating a fast immune response; however, the neutralization capacity increased slowly and required several doses and immunization reinforcements, obtaining a ED50 of 3.30 ?L/g mouse and a neutralization potency of 3.6 mg/mL after 15 immunizations. Conclusions: The hyperimmune llama serum is able to neutralize the lethality of the Bothrops atrox venom from Peru in laboratory mice.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte