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Relationship between p16 and tumor-infiltrating lymphocytes in Peruvian patients with head and neck cancer
No full textFONDECYT 096-2017.Human papillomavirus-16 (HPV-16) infection in Head and Neck Squamous Cell Carcinoma (HNSCC) has a different prevalence through worldwide regions, it influences prognosis and treatment response and p16 staining is its surrogate biomarker. The density and composition of tumor-infiltrating lymphocytes (TIL) reflect biology and prognosis in different malignancies. We characterize TIL in Peruvian patients with HNSCC. We evaluate the influence of clinicopathological features including p16 & ki67 staining in tumor cells over TIL level.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Whole Blood Mycobacterial Growth Assays for Assessing Human Tuberculosis Susceptibility: A Systematic Review and Meta-Analysis
No full textFunding is gratefully acknowledged from: the Wellcome Trust (awards 057434/Z/99/Z, 070005/Z/02/Z, 078340/Z/05/Z, 105788/Z/14/Z, and 201251/Z/16/Z); UK-AID DFID-CSCF; the Joint Global Health Trials Scheme (award MR/K007467/1) with funding from the UK Foreign, Commonwealth and Development Office, the UK Medical Research Council, the UK Department of Health and Social Care through the National Institute of Health Research (NIHR) and Wellcome; the STOP TB partnership's TB REACH initiative funded by the Government of Canada and the Bill & Melinda Gates Foundation (awards W5_PER_CDT1_PRISMA and OPP1118545); CONCYTEC/FONDECYT award code E067-2020-02-01 number 083-2020; and the charity IFHAD: Innovation For Health And Development.Background Whole blood mycobacterial growth assays (WBMGA) quantify mycobacterial growth in fresh blood samples and may have potential for assessing tuberculosis vaccines and identifying individuals at risk of tuberculosis. We evaluated the evidence for the underlying assumption that in vitro WBMGA results can predict in vivo tuberculosis susceptibility. Methods A systematic search was done for studies assessing associations between WBMGA results and tuberculosis susceptibility. Meta-analyses were performed for eligible studies by calculating population-weighted averages. Results No studies directly assessed whether WBMGA results predicted tuberculosis susceptibility. 15 studies assessed associations between WBMGA results and proven correlates of tuberculosis susceptibility, which we divided in two categories. Firstly, WBMGA associations with factors believed to reduce tuberculosis susceptibility were statistically significant in all eight studies of: BCG vaccination; vitamin D supplementation; altitude; and HIV-negativity/therapy. Secondly, WBMGA associations with probable correlates of tuberculosis susceptibility were statistically significant in three studies of tuberculosis disease, in a parasitism study and in two of the five studies of latent tuberculosis infection. Meta-analyses for associations between WBMGA results and BCG vaccination, tuberculosis infection, tuberculosis disease and HIV infection revealed consistent effects. There was considerable methodological heterogeneity. Conclusions The study results generally showed significant associations between WBMGA results and correlates of tuberculosis susceptibility. However, no study directly assessed whether WBMGA results predicted actual susceptibility to tuberculosis infection or disease. We recommend optimization and standardization of WBMGA methodology and prospective studies to determine whether WBMGA predict susceptibility to tuberculosis disease.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
A method to include life cycle assessment results in choosing by advantage (Cba) multicriteria decision analysis. a case study for seismic retrofit in peruvian primary schools
No full textThis research was partially funded by the Consejo Nacional de Ciencia, Tecnolog?a e Innovaci?n Tecnol?gica del Per?, according to the Convenio de Gesti?n N 232-2015-FONDECYT.Building information modeling (BIM) is an emerging technology that improves visualization, understanding, and transparency in construction projects. Its use in Latin America and the Caribbean (LA&C), while still scarce, is developing in combination with multi-criteria decision-making (MCDM) methods, such as the choosing by advantages (CBA) method. Despite the holistic nature of MCDM methods, the inclusion of life cycle environmental metrics is lagging in construction projects in LA&C. However, recent studies point toward the need to optimize the synergies between BIM and life cycle assessment (LCA), in which a method like CBA could allow improving the quality of the decisions. Therefore, the main objective of this study is to integrate LCA and CBA methods to identify the effect that the inclusion of environmental impacts can have on decision-making in public procurement, as well as comparing how this final decision differs from an exclusively LCA-oriented interpretation of the results. Once the LCA was performed, a set of additional criteria for the CBA method were fixed, including transparency, technical, and social indicators. Thereafter, a stakeholder participative workshop was held in order to gather experts to elucidate on the final decision. The methodology was applied to a relevant construction sector problem modelled with BIM in the city of Lima (Peru), which consisted of three different construction techniques needed to retrofit educational institutions. Results from the LCA-oriented assessment, which was supported by Monte Carlo simulation, revealed a situation in which the masonry-based technique showed significantly lower environmental impacts than the remaining two options. However, when a wider range of technical, social, and transparency criteria are added to the environmental indicators, this low-carbon technique only prevailed in those workshop tables in which environmental experts were present and under specific computational assumptions, whereas teams with a higher proportion of government members were inclined to foster alternatives that imply less bureaucratic barriers. Finally, the results constitute an important milestone when it comes to including environmental factors in public procurement in LA&C. © 2021 by the author. Licensee MDPI, Basel, Switzerland.Fondo Nacional de Desarrollo Científico y Tecnológico - Fondecy
Baccharis genistelloides (Lam.) Pers. "carqueja": A review of uses in traditional medicine, phytochemical composition and pharmacological studies [Baccharis genistelloides (lam.) Pers. “carqueja”: Una revisión de usos en medicina tradicinal, composición fitoquímica y estudios farmacológicos]
No full textEste trabajo fue financiado por el CONCYTEC-FONDECYT en el marco de la convocatoria E041-01 [114-2018-FONDECYT-BM-IADT-MU].Background: Baccharis genistelloides (Lam.) Pers. "carqueja" is a species native to South America. The best-known synonyms are B. trimera and B. crispa, used mainly against diabetes, obesity, gastrointestinal and liver problems. The objective of this review is to collect information on its uses in traditional medicine, phytochemical composition, and pharmacological studies. Method: 104 papers, 5 books and 11 theses were obtained from different scientific databases and search engines, referring to Baccharis genistelloides and 13 synonyms, between 1996 and 2020, mainly in English. Results: B. genistelloides is traditionally used in diabetes and obesity. More than 107 compounds have been found in its essential oil, with carquejil acetate as the main compound. 12 flavonoids, 8 clerodan diterpenes and 5 derivatives of caffeoylquinic acid have been reported. The most studied pharmacological activities are the antioxidant capacity and the antibacterial effect. Conclusions: Carquejil acetate is the phytochemical marker for B. genistelloides. Rutin, quercetin, ?-pinene, ?-humulene and trans-caryophyllene have pharmacological activity. It is necessary to carry out pharmacological studies to support its traditional use in diabetes and obesity. © 2021, Ilia State University, Institute of Botany, Department of Ethnobotany. All rights reserved.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Conservation status assessment of the highest forests in the world: Polylepis flavipila forests as a case study
No full textThis research was supported by Consejo Nacional de Ciencia, Tecnolog?a e Innovaci?n Tecnol?gica-CONCYTEC, under Grant 382-2019-FONDECYT-DE; Fondo Nacional de Desarrollo Cient?fico, Tecnol?gico y de Innovaci?n Tecnol?gica [382-2019-FONDECYT]; We thank the ?Servicio Nacional Forestal y de Fauna Silvestre? and the ?Servicio Nacional de ?reas Naturales Protegidas por el Estado? for providing authorizations for research under R.D.G. No. 037-2017-SERFOR/DGGSPFFS and R.D. 009-2018-SERNANP-DGANP, respectively. Likewise, we are grateful to Wendy Carolay Navarro Romo, Ciro Ricardo Paredes Huam?n (Negrito) and Jimy Ronie Llacuachaqui Rodr?guez (Timys) for contributing to field work and making it so much fun.Polylepis forests are one of the most threatened high Andean ecosystems, with 15 species and eight subspecies being categorized as critically endangered, vulnerable or near threatened by IUCN. However, their conservation status is poorly evaluated and could be outdated. As a case study, we evaluated Polylepis flavipila, a species endemic to the Peruvian central Andes, that is categorized as Vulnerable in Peru and is not mentioned in the Global Threatened Species Red List. We used two methods to categorize P. flavipila: (1) a species-level assessment using criteria proposed by IUCN and (2) a population-level assessment of four forests using the more specific criteria proposed by Navarro and collaborators. We recorded 350 relicts of P. flavipila forests as identified from herbariums and other sources. Forest cover was reduced 53% over 45 years as evaluated using satellite images from 1975 and 2020 and we estimated a total area of 458 and 216 km2, respectively. Thus, according to the IUCN criteria, P. flavipila should be classified as Endangered. At the population level, the application of the criteria of Navarro and collaborators results in different threat categories: one of the studied forests is classified as Critically Endangered, two forests as Vulnerable and one as Least Concern. We stress the need for updated categorizations for the 45 described Polylepis tree and shrub species based on the following facts: the only species we tested should change category, the IUCN categorizations were performed 16 to 22 years ago, and there have been many changes in the taxonomy of the genus. The assessment using IUCN criteria should also be complemented with more detailed evaluations at the population level since important differences were detected at a smaller scale, which could help target conservation and restoration resources more efficiently. © 2021 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Fine root dynamics across pantropical rainforest ecosystems
No full textThis study is a product of the Global Ecosystem Monitoring network (GEM), Andes Biodiversity and Ecosystem Research Group (ABERG), Amazon Forest Inventory Network (RAINFOR), Stability of Altered Forest Ecosystem (SAFE), and Instituto de Investigaciones de la Amazonia Peruana (IIAP). WHH was funded by Peruvian FONDECYT/CONCYTEC (grant contract number 213-2015-FONDECYT). The GEM network was supported by a European Research Council Advanced Investigator Grant to YM (GEM-TRAITS: 321131) under the European Union's Seventh Framework Programme (FP7/2007-2013). The field data collection was funded NERC Grants NE/D014174/1 and NE/J022616/1 for in Peru, BALI (NE/K016369/1) for work in Malaysia, the Royal Society-Leverhulme Africa Capacity Building Programme for work in Ghana and Gabon and ESPA-ECOLIMITS (NE/1014705/1) in Ghana and Ethiopia. Plot inventories in South America were supported by funding from the US National Science Foundation Long-Term Research in Environmental Biology program (LTREB; DEB 1754647) and the Gordon and Betty Moore Foundation Andes-Amazon Program. GEM data in Gabon were collected under authorization to YM and supported by the Gabon National Parks Agency. Y.M. is supported by the Jackson Foundation. We would like to acknowledge the GEM team across the tropical regions and countries of Bolivia, Brazil, Ghana, Gabon, Ethiopia, Malaysia, and Peru.Fine roots constitute a significant component of the net primary productivity (NPP) of forest ecosystems but are much less studied than aboveground NPP. Comparisons across sites and regions are also hampered by inconsistent methodologies, especially in tropical areas. Here, we present a novel dataset of fine root biomass, productivity, residence time, and allocation in tropical old-growth rainforest sites worldwide, measured using consistent methods, and examine how these variables are related to consistently determined soil and climatic characteristics. Our pantropical dataset spans intensive monitoring plots in lowland (wet, semi-deciduous, and deciduous) and montane tropical forests in South America, Africa, and Southeast Asia (n = 47). Large spatial variation in fine root dynamics was observed across montane and lowland forest types. In lowland forests, we found a strong positive linear relationship between fine root productivity and sand content, this relationship was even stronger when we considered the fractional allocation of total NPP to fine roots, demonstrating that understanding allocation adds explanatory power to understanding fine root productivity and total NPP. Fine root residence time was a function of multiple factors: soil sand content, soil pH, and maximum water deficit, with longest residence times in acidic, sandy, and water-stressed soils. In tropical montane forests, on the other hand, a different set of relationships prevailed, highlighting the very different nature of montane and lowland forest biomes. Root productivity was a strong positive linear function of mean annual temperature, root residence time was a strong positive function of soil nitrogen content in montane forests, and lastly decreasing soil P content increased allocation of productivity to fine roots. In contrast to the lowlands, environmental conditions were a better predictor for fine root productivity than for fractional allocation of total NPP to fine roots, suggesting that root productivity is a particularly strong driver of NPP allocation in tropical mountain regions. © 2021 The Authors. Global Change Biology published by John Wiley & Sons Ltd.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
La temperatura y radiación solar explican diferencias en la distribución de dos árboles altoandinos (Polylepis spp.) localmente simpátricos en la Cordillera Blanca, Perú
No full textThis work was supported by the Consejo Nacional de Ciencia, Tecnolog?a e Innovaci?n Tecnol?gica (PE) [015-2019- FONDECYT-BM]; FONDECYT-CONCYTEC [N? 237-2015-FONDECYT].Knowledge of the ecological requirements, the current extensions, and cover of a species is important for its management conservation, but this information is lacking for many species of Polylepis (ROSACEA). Here we use niche modeling to understand the ecological requirements of two Polylepis species natively found in sympatry within the Huascarán National Park (HNP) (Cordillera Blanca, Peru), Polylepis albicans and P. webebaueri, and produce species distribution maps restricted by forest cover to estimate each species' current cover within the park. Based on presence/absence data collected systematically throughout their local elevational distribution and analyzed using a Canonical Correspondence Analysis (CCA) and generalized linear models (glm), the best models show that P. albicans and P. weberbaueri have different environmental niches and their occupation is maximized at different climatic ranges mainly associated with temperature (annual mean temperature and mean monthly temperature range) and solar radiation during the dry season. P. albicans occupies warmer and drier areas than P. weberbaueri, which leads to a spatial segregation that has implications for the conservation management of each species. However, it is necessary to evaluate if the models described here adequately capture the environmental niche of other populations of P. weberbaueri, or if these could be new species. Our results indicate that within the HNP, the extension of Polylepis forests (~ 24,000 ha; 11,361 ha of P. albicans and 12,627 ha of P. weberbaueri) is significantly greater than that previously reported and confirm that this protected area harbors the greatest extensions of both species in Peru and its proper management is key for their conservation and that of the ecosystems they constitute. © 2021 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Modulation and Control Strategy for an Isolated and Bidirectional Two-Stage DC-AC converter with a high ripple on the DC-Link to interface Battery with the Single-Phase Grid
No full textThis work was financed by CONCYTEC-FONDECYT within the call for projects E041-01 [Contract Number 176-2018-BM-FT].This paper analyzes the modulation and the control strategy for an isolated and bidirectional two-stage DC-AC converter to interface batteries with the single-phase grid. The converter is composed of a Dual-Active-Bridge Series-Resonant (DABSR) DC-DC converter cascaded with a Voltage Source Inverter (VSI). Both converters are linked by a film capacitor. The time-variant single-phase power is decoupled on the DC-link, which allows a high ripple voltage. In the VSI control, a Notch Filter (NF) is used to filter the low-frequency ripple influence in the grid power transfer. Two different modulations are analyzed to power decoupling in the DABSR DC-DC converter: (1) 50% fixed duty ratio (FDR) with time-variant phase-shift (TVPS) modulation and (2) time-variant duty ratio (TVDR) with fixed phase-shift modulation to power transfer. The analysis for different capacitance values is made considering the ripple on the DC-Link and the THD in the grid current. The results show that 50% FDR and TVPS modulation allows ZVS mode and minimum high-frequency current. However, TVDR allows a better power decoupling in the DC current. The control strategy and modulation are validated by simulation. © 2021 IEEE.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Natural Regeneration After Gold Mining in the Peruvian Amazon: Implications for Restoration of Tropical Forests
No full textWe gratefully acknowledge Laura Cutire, Laura Ramirez, Javier F. Valles, and Erika Sajami for the field work. We also thank the staff of Alwyn Gentry Herbarium of Universidad Nacional Amaz?nica de Madre de Dios and of San Marcos Herbarium of Universidad Nacional Mayor de San Marcos for their technical support in the taxonomic identification. We also thank FONDECYT-CONCYTEC (Fondo Nacional de Desarrollo Cient?fico, Tecnol?gico y de Innovaci?n Tecnol?gica, Per?, award #239-2018) for the fellowship grant to RC-L; CAPES (Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior do Governo do Brasil, Finance Code 001 and #88882.305844/2018-01), FAPESP (Funda??o de Amparo ? Pesquisa do Estado de S?o Paulo, grant #2012/24118-8), and The Royal Society for the fellowship granted to DR; and also FAPESP (grant #2018/22914-8) for the fellowship grant to DOR. Funding. Funding for the field work was provided by the Madre de Dios Consortium-USAID and IIAP (Instituto de Investigaciones de la Amazon?a Peruana).Context: Gold mining is the most destructive activity in the natural forests of the Madre de Dios region in the southeastern Peruvian Amazon. Understanding the natural regeneration process of these degraded areas is necessary to develop forest restoration projects in such conditions. Aims: We aimed to evaluate forest recovery and identify the successional and structure patterns of vegetation governing natural regeneration over time. Methods: Structure, composition, richness, diversity, and successional status were evaluated in abandoned artisanal gold mine areas in Madre de Dios, southeastern Peru. Vegetation data were recorded in 61 plots of 250 m2 established in five sites varying from 1 to 19 years of abandonment. Vegetation in abandoned areas was compared with six undisturbed forests evaluated in previous inventories. Results: In the mining lands, tree density and basal area recovered quickly, while species richness and composition were slow. Forest recovery is an initial stage of transition from pioneer to early secondary species until at least 19 years after abandonment. The most abundant and frequent species were the fast-growing species Ochroma pyramidale and Cecropia engleriana. These species could be considered potential candidates to promote restoration plans. Pioneer species represented 63% of the number of species in plots of 1–4 years, 57% in plots of 5–7 years, and 50% in plots of 8–19 years. Early and late secondary species represented 34 and 16%, respectively, of the number of species in plots of 8–19 years. Abandoned mining and reference plots present less than 5% of species in common. Conclusion: Our results highlight a slow natural regeneration process in areas for up to 19 years after gold mining. Species from different successional statuses were identified as potential candidates for recovering vegetation in such areas. Our findings may have important implications for further research focusing on the ecological restoration in tropical forests severely degraded by gold mining. © Copyright © 2021 Chambi-Legoas, Ortega Rodriguez, Figueiredo, Peña Valdeiglesias, Zevallos Pollito, Marcelo-Peña and Rother.Fondo Nacional de Desarrollo Científico y Tecnológico - Fondecy
Practical Applications of a Vision-based Robot for Security and Safety of Tailings Tunnels Infrastructure in the Mining Industry
No full textACKNOWLEDGMENT This work was financial supported by Concytec-The World Bank Project ”Improvement and Expansion of Services of the National System of Science, Technology and Technological Innovation” 8682-PE, through its executing unit Fondecyt under contract No. 054-2018-FONDECYT- BM-IADT-AV.Furthermore, the authors thank the support of the Pontificia Universidad Catolica del Peru and the Center for Autonomous Systems of the Sydney University of Technology for the support provided during the execution of the research project.In the mining industry, inspection of water recovery tunnels from tailings ponds is a critical activity in order to prevent disasters that could harm personnel, the environment and the infrastructure. Tunnel inspections are considered of high risk due to hazardous conditions such as working near water sources, inside confined spaces and the presence of toxic gases. We propose the use of a vision-based robotic vehicle for water recovery tunnels inspection, improving the security and safety of this high risk but required task. This paper describesthe experience of performing a remote inspection of a tailing pond water recovery tunnel using a robot. The identification of challenges, the establishment of a inspection plan, the remote inspection methodology and the safety regulations required in the mining industry are detailed. After evaluating the performance of the inspection robot in field, the need for a 3D reconstruction functionality in order to improve the tunnel diagnosis was identified. The design, preliminary test and results of the performance of a 3D reconstruction module for the inspection robot are presented and discussed. © 2021 IEEE.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte