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Concordance between micological culture and cytopathology in the diagnosis of dermatophytosis in Guinea pigs
No full textDermatophytosis is a disease that affects the stratum corneum of the skin, hair and nails in Guinea pigs, causing bad aspect of the carcass, affecting its commercialization and generating economic losses. For the study 189 samples of Guinea pigs with dermatological lesions were collected in intensive breeding farms; the Guinea pigs were analyzed by cytopathology and mycological culture in the Laboratory of Microbiology and Microscopy of Universidad Científica del Sur. The frecuency of dermatophytosis was 18.5 ± 5.5 % by mycological culture and 43 ± 7.1 % by cytopathology; according to the age stratum, the dermatophytosis frecuency was 0 % / 0 % in breeding, 25.6 % / 62 % in rearing, and 4.8 % / 6 % in reproductive Guinea pigs by mycological culture and cytopathology, respectively. About the location of the lessions, a frequency of 0 % / 0 % was found in cages by both techniques, while for animals raised in pools a frequency of 26.5 % / 61 % was found by culture and cytopathology, respectively. The grade of congruity between these two tests was determined by the value of Kappa (?) equal to 0.46. The result indicates that there is a moderate degree of association. © 2020 Universidad Politecnica Salesiana. All rights reserved.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Scalpel Region Detection based on the Location of Color Marks and Edge Detection
No full textThis work proposes an algorithm for scalpel region detection using color segmentation and edge detection. The input images are obtained with a fixed camera that has a line of view perpendicular to the scalpel plane. Three squares of red, green and blue colors were added to the scalpel in order to serve as fiducials. For the detection of those marks, the use of two methods was evaluated: One based on the application of thresholds to the color components, and the other based on the use of a fuzzy rule machine. The experimentation shows that both approaches provide similar results. Some morphological operations are then applied in order to detect the scalpel region. The algorithm was successfully tested in several cases, and some examples of the results are presented and analyzed. © 2020 IEEE.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Comparison of GB-SAR Imaging Algorithms for a Landslide Monitoring Application
No full textA comparative analysis of three imaging algorithms for Ground Based Synthetic Aperture Radar (GB-SAR) systems has been conducted in order to select the most appropriate algorithm to be used in a landslide monitoring application. These algorithms are Frequency Domain Back Projection (FDBP), Range Migration Algorithm (RMA), and Discrete Linear Inverse Problem (DLIP). The comparison is based on image reconstruction quality, computational efficiency, and displacement measurement accuracy. Simulated and real data were used to test and compare the algorithms. Results show that FDBP is the most appropriate method for the proposed application. © 2020 IEEE.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Detection of Helicobacter pylori in gastric cancer tissue through histopathology, immunohistochemistry and real-time reverse transcription-PCR
No full textAim: Helicobacter pylori is usually detected based on hematoxylin-eosin (H-E) features, but, immunohistochemistry (IHC) and real-time PCR (RT-PCR) are more precise in chronic-gastritis. We evaluated the relevance of these tests in Peruvian gastric cancer samples. Materials & methods: We performed and evaluated H-E, IHC staining and RT-PCR in 288 gastric tumors. Slides were independently evaluated by three pathologists. Results: H. pylori was detected in 167/287 through H-E, 140/288 through IHC and 175/288 through RT-PCR, and positive-status were associated (p < 0.001). H. pylori detection by H-E had a good concordance with IHC (kappa index = 0.632) but poor with RT-PCR (kappa index = 0.317). Higher median gene-copies were found in high H. pylori density through H-E or IHC (p < 0.001). Conclusion: H-E evaluation is accurate in gastric cancer, and IHC and RT-PCR can complement its results. © 2020 Future Medicine Ltd.. All rights reserved.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
A Network for Advancing Dendrochronology, Dendrochemistry and Dendrohydrology in South America
No full textTree-ring research (TRR) in South America (SA) continues to make important contributions in multiple sub-disciplines, including dendrochemistry and dendrohydrology. This report describes some of the advances in TRR in SA presented in a two-day International Meeting Research entitled "An International Network to Promote Advances in Dendrochronology in South America", organized by the Laboratory of Dendrochronology and Environmental Studies of the Pontifical Catholic University of Valparaíso in Valparaíso, Chile, on January 21-22, 2019. The objective of the meeting was to communicate recent advances in TRR within a network of laboratories in Argentina, Brazil, Chile, Peru, and Uruguay. Novel methodologies and results in dendrochemistry and wood anatomy were also presented by collaborating researchers from German institutions. This report describes some of the research within the subdisciplines of tree-ring science, including dendrochemistry, anatomy and dendrohydrology, and their application to understanding spatio-temporal variability in heavy metal contamination, climate, hydrology, fire regimes and other critical components of South American forest and woodland ecosystems. The meeting demonstrated expansion and diversification of inquiry and applications of TRR in SA, whereby collaboration across research centers has been critical for the advances made in broad-scale comparative studies as well as multi-proxy approaches and the study of global and hemisphere-scale climate phenomena. Copyright © 2020 by the Tree-Ring Society.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Experiments for combustion temperature measurements in a sugarcane bagasse large-scale boiler furnace
No full textThis work presents a numerical and experimental study to measure local combustion temperature from the combustion reactive zone in an industrial sugarcane. A bagasse boiler furnace is utilized preliminary step towards obtaining online three-dimensional temperature measurements. Two different methods were used for in situ measurement of local temperatures in a sugarcane bagasse flame: Spectral Analysis and Image Processing in the Visible Spectrum. The maximum instantaneous temperatures found in the focused reactive zone area of the bagasse flame were 1623 K and 1520 K by the spectrometric and imaging system respectively and the time average maximum flame temperatures measured were 1443 K and 1496 K. Additionally, a set of flame temperature measurement tests was carried out in a laboratory furnace by the spectrometric method and a time average flame temperature of 1569 K was noted. The flame temperatures found in this work show reasonable agreement with results of CFD simulations and results obtained in laboratory tests which were also reported in the literature. Intensity of emission lines of alkali metal (K) were measured in the flame spectra during the bagasse combustion. Spectral flame emissivity was estimated for an industrial level operating condition. © 2020 Elsevier LtdConsejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Andean lupin (Lupinus mutabilis Sweet): Processing effects on chemical composition, heat damage, and in vitro protein digestibility
No full textBackground and objective: Andean lupin (Lupinus mutabilis Sweet) has health benefits with promising possibilities for food industry. The aim of this research was to determine the effect of processing (water debittering, extrusion, and spray-drying) on chemical composition, heat damage and in vitro protein digestibility in Andean lupin. Findings: The processing treatment modified all the parameters while the genotype showed limited effect. The untreated lupins had high protein and lipid content (47.4 and 16.2 g/100 g dry matter). The extruded products showed higher protein content (55.7 g/100 g) and digestibility (68.1%) than the untreated lupins, along with limited heat damage (8.7 mg furosine/100 g protein). Spray-drying led to the lowest protein content (31.8 g/100 g) and, when maltodextrin was used, the highest heat damage (54.1 ± 20.7 mg furosine/100 g protein; 0.60 mg hydroxymethylfurfural/kg; 0.58 mg glycosylisomaltol/kg), but also to the maximum protein digestibility (72.8%–74.0%). Conclusions: The chemical composition of Andean lupin was improved by the technological treatments (debittering, extrusion, and spray-drying) applied. Processing enhanced nutritional value and digestibility, without inducing relevant heat damage. Significance and novelty: Extrusion and spray-drying improve the in vitro protein digestibility of Andean lupin flour causing limited heat damage. © 2020 Cereals & Grains AssociationFondo Nacional de Desarrollo Científico y Tecnológico - Fondecy
Oropouche infection a neglected arbovirus in patients with acute febrile illness from the Peruvian coast
No full textObjective: To evaluate the frequency of infection caused by the Oropouche virus (OROV) in 496 patients with acute febrile disease (AFI), whose samples were obtained for the analysis of endemic arboviruses in a previous investigation carried out in 2016. Results: OROV was detected in 26.4% (131/496) of serum samples from patients with AFI. Co-infections with Dengue virus (7.3%), Zika virus (1.8%) and Chikungunya (0.2%) were observed. The most common clinical symptoms reported among the patients with OROV infections were headache 85.5% (112/131), myalgia 80.9% (106/131), arthralgia 72.5% (95/131) and loss of appetite 67.9% (89/131). Headache and myalgia were predominant in all age groups. Both OROV infections and co-infections were more frequent in May, June and July corresponding to the dry season of the region. © 2020 The Author(s).Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Assessing soil erosion risk at national scale in developing countries: The technical challenges, a proposed methodology, and a case history
No full textThrough an extensive bibliographic review, this contribution underlines the urgency and challenges to quantify soil erosion rates (ERs) in developing countries. It subsequently elaborates on the combined application of GIS-based RUSLE, generalized likelihood uncertainty estimation (GLUE) principles and sediment delivery ratio functions (SDR) to quantify ERs at country scale for these countries, as they commonly have limited measurements to that purpose. The methodology, termed RUSLE-GGS (RUSLE-GIS-GLUE-SDR) herein, comprises the following sequence: (1) construction of ER samples using RUSLE-GIS based on freely available local/global geoenvironmental observations and field relations, (2) construction of area-specific sediment yield samples utilizing SDR transfer functions, and (3) assessment of the most behavioral samples by means of bias analysis and cross validation. Its application to Peru allows obtaining 5-km resolution ER and potential erosion maps for the years 1990, 2000, and 2010. RUSLE-GGS is highly replicable and could potentially be used as an initial standard and systematic method to estimate ERs in developing countries through the active participation of local scientists. Thus, it potentially can contribute to improve the capacity building in such countries and set an initial frame to compare the evolution of soil erosion in their territories towards attaining Goal 15 of the UN 2030 Agenda for Sustainable Development.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Change of the rainfall seasonality over central peruvian andes: Onset, end, duration and its relationship with large-scale atmospheric circulation
No full textChanges of the onset dates, end dates, and duration of the rainy season over central Peruvian Andes (Mantaro river basin, MRB) could severely affect water resources management and the main economic activities (e.g., rainfed agriculture, raising cattle, among others). Nonetheless, these changes have not been documented for the Tropical Andes. To asses that, we used daily datasets of observed rainfall during the 1965-2013 period. For this period, the average onset (end) date of the rainy season over the MRB occurs in the pentad 17 (19-23 September) [pentad 57 (7-11 April)]. The duration of the rainy season mainly is modulated by the onset dates due to it has higher variability than end dates. There is a reduction of 3 days/decade in the duration of wet season over the MRB for the last four decades due to the delay of the onset days. Furthermore, El Nino favors late-onset and early end of the rainy season, while La Nina favors early onset and late end of the rainy season in the MRB. Onset dates are related to the propagation of the convective region of the South American Monsoon System (SAMS), from the Caribbean region toward the central Amazon basin. Early (late)-onset days are associated with a southward (northward) shift of the South Atlantic Convergence Zone (SACZ) and weak (strong) convection over equatorial Atlantic that induces the southernmost propagation (eastward shift) of the SAMS. © 2020 by the authors.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte