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PublicaciónTotal Fat Content and Fatty Acid Profile of Fine-Aroma Cocoa From Northeastern Peru(Frontiers Media S.A., 2021)Cocoa beans are the raw material for the chocolate industry. In this study, the total fat contents and fatty acid profiles of fine-aroma cocoa beans of 30 cocoa ecotypes from northeastern Peru were evaluated. Results showed that SJJ-1 and ACJ-11 ecotypes from San Martin and Amazonas regions, respectively, presented highest percentages of total fat with an average of 30.49%. With respect to fatty acid profiles, it was found that cocoa ecotypes are composed of 10 fatty acids (C14:0, C16:0, C16:1, C18:0, C17:0, C18:1, C18:2, C18:3, C20:0, and C22:0); based on this profile, 5 clusters were determined. Cluster 5 had the highest content of C17:0 fatty acid (0.47%); however, the clusters 1, 2, 3, and 4 had the lowest content of this fatty acid (0.37%, 0.32%, 0.32%, respectively). The clusters 3 and 4 showed the highest content of C16:0 fatty acid (31.13% y 28.97%, respectively). The clusters 3 and 5 contained the highest content of the acid C18:1 (27.08% y 26.82%, respectively). The PCA found that C18:0 and C20:0 fatty acids are correlated, and are fundamentally opposite to C18:1, C16:0, and C18:3 acids. These results may be useful in identifying raw material for the development of specialty chocolates with better nutritional value than traditional cocoa. © Copyright © 2021 Oliva-Cruz, Mori-Culqui, Caetano, Goñas, Vilca-Valqui and Chavez.
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PublicaciónDetection of intracellular reactive oxygen species (superoxide anion and hydrogen peroxide) and lipid peroxidation during cryopreservation of alpaca spermatozoa(John Wiley & Sons, 2017)The objective was to detect changes in intracellular reactive oxygen species (superoxide anion and hydrogen peroxide) production and lipid peroxidation during cryopreservation of alpaca spermatozoa. Twelve alpaca semen samples were conventionally cryopreserved. Results showed that high percentage of viable alpaca spermatozoa produces intracellular reactive species oxygen (ROS) during the cryopreservation process of alpaca semen.
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PublicaciónAn ecological overview of Prosopis pallida, one of the most adapted dryland species to extreme climate events(Academic Press, 2021)Prosopis pallida (algarrobo) is a highly adapted species to extremely dry and wet conditions. Its geographic distribution at both sides of the Pacific Ocean is associated with its plastic response to El Niño event, an extreme climate event that changes precipitation regimes. In this review, we summarized the current knowledge of this versatile species based on scientific literature. Our analysis conducted identify three main research topics: geographical distribution, ecophysiology and population plasticity, and ecosystem services provision to guide the review in a methodological and unbiased way. In the geographical distribution section, we describe the origin, history, and native distribution of algarrobo, as well as the current distribution and the degree of invasiveness in some countries. In the ecophysiology and population plasticity section, we focus on the mechanisms used by algarrobo to avoid water stress during drought and maximize plant growth during El Niño. We discuss how this is reflected in the most important leaf functional traits, such as leaf mass per area (LMA) or gas exchange-related traits. We analyse the importance of phenotypic plasticity and intraspecific variability as adaptive ways to resist extreme rainfall and prolonged droughts on P. pallida growth during the last 50 years. Finally, we summarized the main ecosystem services and ecological benefits provided by P. pallida as well as its potential industrial uses. With this review, we wish to consolidate the current scientific knowledge of this species, to point out gaps of knowledge and suggest future research directions. As the world becomes a warmer place, P. pallida can be a key species to understand plant resilience to extreme events in dryland ecosystems. © 2021 Elsevier Ltd
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PublicaciónDistribution of indium, germanium, gallium and other minor and trace elements in polymetallic ores from a porphyry system: The Morococha district, Peru(Elsevier B.V., 2021)We report indium, germanium, gallium, and other minor and trace elements contents in sphalerite, chalcopyrite, galena, and tetrahedrite-tennantite occurring in skarn and skarn-free (“Cordilleran”) polymetallic mantos and vein ore bodies in the Miocene porphyry-related Morococha District, Central Peru. Among the investigated minerals, LA-ICP-MS measurements indicate that In and Ga concentrate mostly in sphalerite (Inter-Quartile Range [IQR] 217–2.7 ppm and up to 4608 ppm In; IQR 61–2.0 ppm and up to 2137 ppm Ga) and chalcopyrite (IQR 109–32 ppm and up to 1070 ppm In; IQR 62–1.5 ppm and up to 630 ppm Ga). In coeval generations of sphalerite and chalcopyrite, the contents of In and Ga in sphalerite are at least two times higher than in chalcopyrite. Germanium content is generally low in the four analyzed minerals (IQR 1.2–0.19 ppm), although late Fe-poor sphalerite may yield much higher values (IQR 129–74 ppm). Certain trace element contents appear to correlate with (i) the evolving characteristics of the hydrothermal fluids during individual mineralization events, and (ii) the location of the studied ore bodies relative to the hydrothermal feeders. The highest In values in sphalerite are found in high-sulfidation assemblages in Cordilleran polymetallic veins and, with lower amounts, in low-sulfidation assemblages in skarn bodies. In intermediate-sulfidation assemblages in Cordilleran mineralization, In content decreases from early to late generations of sphalerite, while that of Ge increases. Spatial trace-element trends in Cordilleran veins and replacement bodies formed during the so-called “Morococha district-scale polymetallic event” include, from porphyry-distal to porphyry-proximal locations: i) In and Cu, and to a lesser extent Ga, enrichment in sphalerite; ii) Se and Hg enrichment and Sn and Ag depletion in chalcopyrite; iii) In enrichment in galena; and iv) Ag depletion in tetrahedrite-tennantite. Our dataset suggests that In is incorporated in the sphalerite crystal lattice via coupled substitutions involving Cu and subordinately also Sn and Ag. Availability of Cu in the mineralizing fluids is therefore key to In enrichment in sphalerite. Progressive dilution of metal-rich magmatic-hydrothermal fluids and Cu precipitation probably account for the progressive In depletion in distal-to-porphyry Zn-Pb-Ag and Ag-Pb Cordilleran polymetallic mineralization and in late sphalerite generations in intermediate-sulfidation assemblages. © 2021 Elsevier B.V.
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PublicaciónTaxonomy of Centropomus Lacépède, 1802 (Perciformes: Centropomidae), with focus on the Atlantic species of the genus(Magnolia Press, 2021)Centropomus Lacépède, 1802 comprises 13 species of the fishes popularly knows as snooks, distributed in both Atlantic and Pacific coasts of America. Despite several studies on the group, conflicting taxonomic classifications still exist, including overlapping diagnostic characters, rendering species diagnoses extremely difficult. Herein, we review the taxonomy of Centropomus to elucidate species identities, redefine their diagnoses and to assess interspecific relationships based on the examination of 376 specimens. The study included complementary approaches, as analyses of external morphologic characters, linear and geometric morphometrics, and molecular analyses. Forty-nine characters were used for external morphology, 17 discrete plus 32 linear measurements. Shape and size were analyzed through geometric morphometrics of 185 specimens in lateral view. Partial sequences of the gene cytochrome c oxidase I were obtained for 129 specimens representing 11 species. Based on the consistent results retrieved from the morphologic and molecular analyses, we recognized six species of Centropomus from the Atlantic coast (C. ensiferus, C. irae, C. parallelus, C. pectinatus, C. poeyi and C. undecimalis). Centropomus mexicanus is treated as a junior synonym of C. parallelus. Six species from the Pacific coast are also tentatively recognized (C. armatus, C. medius, C. nigrescens, C. robalito, C. unionensis, and C. viridis), however further studies on the Pacific species are still needed. Information on type material, diagnosis, distribution, and taxonomic comments are provided for each species. An identification key to the species of Centropomus is presented. Copyright © 2021 Magnolia Press