Browsing by Fecha, starting with "2018"

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Volatolome of the Female Genitourinary Area: Toward the Metabolome of Cervical Cancer
(Elsevier BV, 2018) Miriam Rodríguez-Esquivel; Juan José Rosales; Rafael López Castro; Teresa Apresa-García; Ónix Garay; Pablo Romero-Morelos; Daniel Marrero–Rodríguez; Keiko Taniguchi‐Ponciano; Ricardo López-Romero; Héctor Guerrero-Flores
Methodology to support decision-making in prioritization improvement plans aimed at agricultural sector: Case study
(National University of Colombia, 2018) Nelson Javier Tovar Perilla; Helga Patricia Bermeo Andrade; José Fidel Torres-Delgado; Miguel I. Gómez
Los países en desarrollo y aquellos con tradición agrícola tienen entre sus prioridades gubernamentales el diseño e implementación de planes de mejora para aumentar la productividad en este sector. La priorización de esos planes tiende a basarse en la evaluación de indicadores de producción, dejando de lado aspectos logísticos clave como transporte, manipulación, embalaje, entre otros. Por esta razón, este trabajo propone una metodología multicriterio, basada en el método de expertos y el método de planificación del desarrollo tecnológico en cadenas agroindustriales propuesto por ISNAR, que estiman el índice de potencial logístico (LPi) y el índice de nivel de competitividad (LCi). El análisis conjunto de ambos indicadores permitió priorizar los productos en una matriz denominada matriz de priorización. La metodología fue validada en un caso de estudio a través de la priorización de productos hortícolas y frutales en cinco zonas del Tolima - Colombia para asignar recursos con el fin de implementar estrategias logísticas.
Bibliotecas nacionales y accesibilidad web. Situación en América Latina
(Universidad de Antioquia, 2018) Yudayly Stable Rodríguez; Carlos Antonio Sam-Anlas; Carlos Antonio Sam-Anlas; Biblioteca Nacional del Perú
This study presents the accessibility situation of main pages of the websites of 16 national libraries in Latin America, taking in account its compliance with web accessibility guidelines established by the World Wide Web Consortium in recommendation 2.0. The evaluation was carried out using the web accessibility tool TAW, which allows automatic analysis of the difficulties in accessing the web, based on the four principles, guidelines, and 14 accessibility indicators. As a result it was clear that websites analyzed do not have an acceptable accessibility level, due to the fact that accessibility success rate criteria was 19.9 %, indicator that does not achieve an average result, and only two indicators achieve values over than 50 %. Taking in account all this, it is recommended to make corresponding adjustments in order to solve the problems that make difficult web accessibility to the main page of these libraries, and also to carry out periodical checks using defined tool, or others that can contribute to the solution of these problems.
Efficiency of High Altitude On-shore Wind Turbines: Air Density and Turbulence Effects—Qollpana Wind Farm (Bolivia)
(2018) Rober Mamani; Norbert Hackenberg; Patrick Hendrick
The wind energy is one of the most important alternatives for renewable and clean electricity generation. During the last decade the number of wind farms has largely increased in South America. Qollpana is only one case of an on-shore wind farm but it is located at 2900 m above sea level over a complex terrain. Due to high altitude, the air density is reduced by 27% compared with sea level and the topographic characteristics induce a high level of turbulence. Qollpana wind farm has ten wind turbines reaching 27 MW of installed capacity. October is the month of highest wind average velocity and February with the lowest one. This work analyses the capacity factor of the wind farm, also the air density and the turbulence effects on wind turbine efficiency. The main results show that monthly capacity factor varies between 0.08 and 0.67 in the wind farm. Moreover, the results have shown a considerable effect of the turbulence intensity on the turbines efficiency.
La Contabilidad de la Gestión Ambiental Empresarial y sus Paradigmas hacia la Construcción de las Bases Teóricas
(University of the Andes, 2018) Galia Beatriz Chacón Parra; Olga Paredes de Molina; María Estela Quintero de Contreras; María Zuleyma Rosales Sánchez
The environmental management is present in the financial information of companies, giving rise to the accounting of the environmental management, which is considered as the accounting that elaborates, analyzes and interprets objective and timely information for the short and long-term decision making, in a set of strategies that allow the company to achieve its objectives and goals. Therefore, it is an accounting for the control of companies that should focus their attention on making accounting records that allow the measurement and valuation of operations concerning the environment, obtaining an accounting in accordance with the norms and regulations established for that purpose, both legal and countable The objective of the article is to build the theoretical and legal foundations of corporate environmental management accounting. The methodology used is of a documentary research and content analysis was used for the analysis of the information, whose objective is the condensed representation of the information for its storage and consultation, establishing inferences or explanations in the companies. The main findings were to determine that the Constitution (1999) and the LOA (2006) are the fundamental Venezuelan legal pillars of environmental management, concluding with the need for companies to assume socially responsible behavior and account by incorporating the environmental accounting variable among other social aspects.
Leishmanicidal activity of onopordopicrin isolated from the leaves of Brachylaena discolor
(University of Bern, 2018) Julião Monjane; Diandra Capusiri; Alberto Giménez; Olov Sterner
Brachylaena discolor (Asteraceae) is a medicinal plant used in Mozambique to treat stomachache, tuberculosis, and diabetes. To discover new lead compounds with leishmanicidal activity, a methanolic extract of the leaves of this plant was investigated. Through fractionation, employing several chromatographic methods, two sesquiterpene lactones onopordopicrin (1) and its germacronolide epoxide derivative (2), together with other ten know phenolic compounds derivatives (3-12) were isolated. The structures of the isolated compounds were determined by spectroscopic methods, mainly 1D and 2D NMR experiments, as well as by comparing their spectroscopic data as reported in the literature. Compounds 1 and 2 were evaluated for their leishmanicidal activity using the Colorimetric method-XXT. Compound 1 showed a significant leishmanicidal activity against Leishmania amazonensis and L. braziliensis (IC50 values 39.6 and 27.9 μM, respectively) as compared to miltefosine (12.5 and 12.0 μM, respectively), a currently used agent to treat leishmaniosis. While compound 2 was inactive against both stains tested with IC50 values >50μM compared with the same agent. Compounds 3-12 were not assayed for leishmanicidal activity. This is the first study reporting the above-mentioned activity of onopordopicrin (1). The results could suggest that compound 1 is a promising lead structure to treat leishmaniosis.
Conocimiento popular acerca de la k’allampa de pino (Suillus luteus (L.) Roussel) en la localidad de Alalay, Mizque (Cochabamba, Bolivia): un ejemplo de diálogo de saberes
(2018) Elizabeth Melgarejo-Estrada
La etnomicología en Bolivia ha recibido poca atención a lo largo de su historia, ello se ve reflejado en la escasa y dispersa información que existe en la actualidad. Este estudio se centra en comprender la perspectiva de una comunidad quechua respecto a la K’allampa de pino (Suillus luteus) y la gestión de su aprovechamiento, como muestra de un conocimiento micológico popular en la localidad de Alalay (Mizque, Cochabamba), donde se estableció un diálogo de saberes entre comunarios y acádemicos. Se realizaron entrevistas semiestructuradas a 20 hombres y mujeres quechua, empleando muestreo tipo bola de nieve y técnicas de observación participante para aproximarnos a la percepción y usos de la K’allampa, prácticas de recolecta, aspectos económicos y transmisión del conocimiento, variables que fueron analizadas por contrastación de categorías. La recolección y el deshidratado de las K’allampas se realiza en época de lluvias y representan para la comunidad actividades de recreación, buen comer, además de ser incorporado a platos autóctonos y ser una actividad económica complementaria de gran importancia, para al menos el 80% de la comunidad. Por otra parte, la transmisión del conocimiento popular recientemente adquirido es horizontal y vertical. Este encuentro de diálogo de saberes representa un ejemplo exitoso y visible en la comunidad, ya que a partir del diálogo se establecieron mejoras en las técnicas de recolección y deshidratado, así como la promoción de una feria local autónoma que promueve el consumo de la K’allampa de pino.
Lieux d’apprentissage et dynamiques des savoirs apicoles au Maroc
(Presses de Sciences Po, 2018) Antonin Adam; Geneviève Michon; Jean-Michel Sorba; Lahoucine Amzil
Resumé Présente dans la majeure partie du monde, l’apiculture repose sur des savoirs, des objets et des cultures techniques fortement diversifiés. Sa pratique résulte tout à la fois d’un apprentissage par expérience, de lectures d’ouvrages savants et d’enseignements académiques. Ces enseignements sont érigés sur les bases de recherches scientifiques et d’un savoir technique formalisé portant notamment sur la biologie de l’abeille. Aujourd’hui, ce savoir formalisé et homogénéisé est diffusé dans des espaces où d’autres savoirs, éprouvés par le temps long, sont encore présents. C’est le cas du Maroc, où se côtoient et s’hybrident souvent, savoirs formels et expérience locale. Cet article se propose d’étudier les conséquences de cette rencontre sur les lieux d’apprentissage, les réseaux socioprofessionnels et les enseignements dispensés sous l’égide des institutions agricoles et entre pairs (associations spécialisées et apiculteurs renommés). La perspective de la recherche est l’analyse d’un processus d’hybridation et de ses effets sur la transmission des savoirs dans un contexte de circulation élargie des savoirs.
Acotaciones al estudio de Carmen Chinchilla sobre las sociedades públicas y la responsabilidad por sus deudas
(Center for Political and Constitutional Studies, 2018) Mercedes Fuertes López
Explica la autora, por un lado, su opinin sobre cundo debe trasladarse la responsabilidad por las deudas de una sociedad pblica a la Administracin matriz, as como la necesidad de exigir la debida responsabilidad contable y patrimonial a los miembros del Consejo de Administracin. Por otro, admite la existencia de una personalidad jurdica separada de las sociedades pblicas y la mixtura del rgimen jurdico aplicable. Rgimen jurdico que debe preservar algunos criterios de derecho pblico pero que ha de mantener en todo caso una indispensable esencia mercantil.
Weaving Indigenous Textile Art Into Cardiac Devices
(American Medical Association, 2018) Alexandra Heath; Alexander J. Javois; Franz Freudenthal
This Arts and Medicine essay describes how indigenous Aymara women in La Paz, Bolivia, are using traditional weaving techniques and patterns to create cardiac devices for occlusion of large congenital heart defects in children.
Bolivian anthophilous Cerambycinae (Coleoptera: Cerambycidae) host flower records
(University of Nebraska–Lincoln, 2018) Robin O. S. Clarke; Sonia Zamalloa
Clarke, Robin, Zamalloa, Sonia (2018): Bolivian anthophilous Cerambycinae (Coleoptera: Cerambycidae) host flower records. Insecta Mundi 2018 (640): 1-35, DOI: 10.5281/zenodo.4645968
Effects of grazing pressure on plant species composition and water presence on bofedales in the Andes mountain range of Bolivia
(International Mire Conservation Group and International Peat Society, 2018) N. Cochi Machaca; Bruno Condori; Adara Pardo; Fabien Anthelme; Rosa Isela Meneses; C.E. Weeda; Humberto L. Perotto‐Baldivieso; UMR AMAP, IRD, CIRAD, CNRS, INRA, Université de Montpellier, Montpellier, France; Herbario Nacional de Bolivia, Universidad Mayor de San Andrés, La Paz, Bolivia; Museo Nacional de Historia Natural, La Paz, Bolivia
Bofedales are high-Andean peatland plant communities with high capacity for water retention, which are regarded as oases of biodiversity. These areas have great social and economic value for livestock grazing, which plays an important role in their vegetation dynamics. However, the effects of increased livestock pressure on vegetation composition and surface water have not yet been clarified. The goal of this study was to assess the impact of current grazing practices on bofedal vegetation, species diversity and function. Specifically, the study aimed to (1) quantify carrying capacity and stocking rate in grazed bofedales and (2) quantify the effects of grazing pressure on plant composition and the extents of bare soil and surface water. Biomass and stocking rate estimates for 25 bofedales along the Cordillera Real (Tropical Andes, Bolivia) showed that all bofedales were overgrazed (carrying capacity/stocking rate (CC/SR) <1). Regression analyses showed significant decreases in number of plant species, species dominance, diversity and percent surface water as CC/SR declined (p < 0.05). Bofedales are negatively affected by increased grazing pressure and potentially affected by changes in livestock species. These pressures, combined with land use changes and climate change, could result in long-term negative effects for the ecological functioning and sustainability of bofedales.
Epidemiology of zoonotic tick-borne diseases in Latin America: Are we just seeing the tip of the iceberg?
(Faculty of 1000, 2018) Alfonso J. Rodríguez‐Morales; D. Katterine Bonilla‐Aldana; Samuel E. Idarraga-Bedoya; Juan Javier García-Bustos; Jaime A. Cardona‐Ospina
<ns5:p>Ticks are responsible for transmission of multiple bacterial, parasitic and viral diseases. Tick-borne diseases (TBDs) occur particularly in tropical and also subtropical areas. The frequency of these TBDs has been increasing and extending to new territories in a significant way, partly since ticks’ populations are highly favored by prevailing factors such as change in land use patterns, and climate change. Therefore, in order to obtain accurate estimates of mortality, premature mortality, and disability associated about TBDs, more molecular and epidemiological studies in different regions of the world, including Latin America, are required. In the case of this region, there is still a limited number of published studies. In addition, there is recently the emergence and discovering of pathogens not reported previously in this region but present in other areas of the world. In this article we discuss some studies and implications about TBDs in Latin America, most of them, zoonotic and with evolving taxonomical issues.</ns5:p>
Fatal Dengue, Chikungunya and Leptospirosis Co-Infection: The Febrile Patient in Tropical Areas, Importance of Co-Infection Assessment
(2018) Jaime A. Cardona‐Ospina; Carlos Eduardo Jiménez-Canizales; Heriberto Vásquez-Serna; Jesús Alberto Garzón-Ramírez; José Fair Alarcón-Robayo; Juan Alexander Cerón-Pineda; Alfonso J. Rodríguez‐Morales
Background: The febrile patient from tropical areas, in which emerging arboviruses are endemic, represent a diagnostic challenge and potential co-infections with other pathogens (i.e bacteria or parasites) are usually overlooked. Objectives: We present a case of an elderly woman diagnosed with dengue, chikungunya and Leptospira interrogans co-infection. Study Design: Case report. Results: An 87-year old woman from Colombia complained of upper abdominal pain, arthralgia, myalgia, hyporexia, malaise and intermittent fever accompanied with progressive jaundice. She had a medical history of chronic heart failure (Stage C, NYHA III), without documented cardiac murmurs, right bundle branch block, non-valvular atrial fibrillation, hypertension, and chronic venous disease. Her cardiac and pulmonary status quickly deteriorated after 24 hours of her admission without electrocardiographic changes and she required ventilatory and vasopressor support. In the next hours the patient evolved to pulseless electrical activity and then she died. Dengue IgM, NS1 ELISA, MAT for Leptospira interrogans and RT-PCR for chikungunya, were positive. Discussion: This case illustrates a multiple co-infection in a febrile patient from a tropical area of Latin America that evolved to death.
Latin Americans show wide-spread <i>Converso</i> ancestry and the imprint of local Native ancestry on physical appearance
(2018) Juan Camilo Chacón-Duque; Kaustubh Adhikari; Macarena Fuentes‐Guajardo; Javier Mendoza‐Revilla; Victor Acunñ-Alonzo; Rodrigo Barquera; Mirsha Quinto‐Sánchez; Jorge Gómez‐Valdés; Paola Everardo; Hugo Villamil‐Ramírez
Historical records and genetic analyses indicate that Latin Americans trace their ancestry mainly to the admixture of Native Americans, Europeans and Sub-Saharan Africans 1 . Using novel haplotype-based methods here we infer the sub-populations involved in admixture for over 6,500 Latin Americans and evaluate the impact of sub-continental ancestry on the physical appearance of these individuals. We find that pre-Columbian Native genetic structure is mirrored in Latin Americans and that sources of non-Native ancestry, and admixture timings, match documented migratory flows. We also detect South/East Mediterranean ancestry across Latin America, probably stemming from the clandestine colonial migration of Christian converts of non-European origin ( Conversos ). Furthermore, we find that Central Andean ancestry impacts on variation of facial features in Latin Americans, particularly nose morphology, possibly relating to environmental adaptation during the evolution of Native Americans.
Real Time PCR for the Evaluation of Treatment Response in Clinical Trials of Adult Chronic Chagas Disease: Usefulness of Serial Blood Sampling and qPCR Replicates
(2018) Rudy Parrado; Ramírez Jc; Anabelle de la Barra; Cristina Alonso‐Vega; Natalia Juiz; Lourdes Ortiz; Daniel Illanes; Faustino Torrico; Joaquím Gascón; Fabiana Alves
Abstract This work evaluated a serial blood sampling procedure to enhance the sensitivity of duplex real time PCR (qPCR) for baseline detection and quantification of parasitic loads and post-treatment identification of failure in the context of clinical trials for treatment of chronic Chagas disease, namely DNDi-CH-E1224-001 ( NCT01489228 ) and MSF-DNDi PCR sampling optimization study ( NCT01678599 ). Patients from Cochabamba (N= 294), Tarija (N = 257), and Aiquile (N= 220) were enrolled. Three serial blood samples were collected at each time-point, and qPCR triplicates were tested per sample. The first two samples were collected during the same day and the third one seven days later. A patient was considered PCR positive if at least one qPCR replicate was detectable. Cumulative results of multiple samples and qPCR replicates enhanced the proportion of pre-treatment sample positivity from 54.8 to 76.2%, 59.5 to 77.8%, and 73.5 to 90.2% in Cochabamba, Tarija, and Aiquile cohorts, respectively and increased cumulative detection of treatment failure from 72.9 to 91.7%, 77.8 to 88.9%, and 42.9 to 69.1% for E1224 low, short, and high dosage regimes, respectively; and from 4.6 to 15.9% and 9.5 to 32.1% for the benznidazole (BZN) arm in the DNDi-CH-E1224-001 and MSF-DNDi studies, respectively. The monitoring of patients treated with placebo in the DNDi-CH-E1224-001 trial revealed fluctuations in parasitic loads and occasional non-detectable results. This serial sampling strategy enhanced PCR sensitivity to detecting treatment failure during follow-up and has the potential for improving recruitment capacity in Chagas disease trials which require an initial positive qPCR result for patient admission.
DNA Methylation Explains a Subset of Placental Gene Expression Differences Based on Ancestry and Altitude
(2018) William E. Gundling; Priyadarshini Pantham; Nicholas P. Illsley; Lourdes Echalar; Stacy Zamudio; Derek E. Wildman
Abstract: Objectives : The most pronounced effect of high altitude (>2700m) on reproductive outcomes is reduced birth weight. Indigenous Bolivians (Andean Native Americans) residing for generations at high altitudes have higher birth weights relative to more recent migrants of primarily European ancestry. Previous research demonstrated that the placenta is a key contributor to the preservation of Andean birth weight at high altitude. Our current research investigated how gene expression and epigenetics contributes to the conservation of birth weight at high altitude by examining mRNA expression and DNA methylation differences between placentas of Andeans and those of European ancestry residing at high and low altitude. Methods : Genome-wide mRNA expression and DNA methylation of villous placenta tissue was quantified utilizing microarray technology. Subjects were of Andean and European ancestry and resident at high (3600m) or low (400m) altitudes. Differentially expressed genes (DEGs) associated with altitude or ancestry were identified (FDR<0.1, |fold change|>1.25). To predict which DEGs could be regulated by methylation we tested for correlation between gene expression and methylation values. Results : 69 DEGs associated with altitude (n=36) or ancestry (n=34) were identified. Altitude-associated DEGs included members of the AP-1 transcription factor family. Ancestry-associated DEGs were implicated in inflammatory pathways and associated with pro-angiogenic macrophages. More ancestry-associated DEGs correlated significantly (n=17) (FDR<0.1) with promoter or gene body methylation (p=0.0242) when compared to altitude associated DEGs (n=8). Conclusions: Compared to altitude-associated DEGs, methylation regulates more ancestry-associated DEGs, potentially allowing for rapid modification in the expression of inflammatory genes to attract pro-angiogenic macrophages as a means of promoting placental capillary growth in Andeans, regardless of altitude.
The genetic prehistory of the Andean highlands 7,000 Years BP though European contact
(2018) John Lindo; Randall Haas; Courtney A. Hofman; Mario Apata; Mauricio Moraga; Ricardo A. Verdugo; James T. Watson; Carlos Viviano Llave; David Witonsky; Enrique Pacheco
Abstract The peopling of the Andean highlands above 2500m in elevation was a complex process that included cultural, biological and genetic adaptations. Here we present a time series of ancient whole genomes from the Andes of Peru, dating back to 7,000 calendar years before present (BP), and compare them to 64 new genome-wide genetic variation datasets from both high and lowland populations. We infer three significant features: a split between low and high elevation populations that occurred between 9200-8200 BP; a population collapse after European contact that is significantly more severe in South American lowlanders than in highland populations; and evidence for positive selection at genetic loci related to starch digestion and plausibly pathogen resistance after European contact. Importantly, we do not find selective sweep signals related to known components of the human hypoxia response, which may suggest more complex modes of genetic adaptation to high altitude. One Sentence Summary Ancient DNA from the Andes reveals a complex picture of human adaptation from early settlement to the colonial period.
Mapping diversification metrics in macroecological studies: Prospects and challenges
(2018) Julián A. Velasco; Jesús N. Pinto‐Ledezma
Abstract The intersection of macroecology and macroevolution is one of the most active research areas today. Macroecological studies are increasingly using phylogenetic diversification metrics to explore the role of evolutionary processes in shaping present-day patterns of biodiversity. Evolutionary explanations of species richness gradients are key for our understanding of how diversity accumulated in a region. For instance, the present-day diversity in a region can be a result of in situ diversification, extinction, or colonization from other regions, or a combination of all of these processes. However, it is unknown whether these metrics capture well these diversification and dispersal processes across geography. Some metrics (e.g., mean root distance -MRD-; lineage diversification-rate -DR-; evolutionary distinctiveness -ED-) seem to provide very similar geographical patterns regardless of how they were calculated (e.g., using branch lengths or not). The lack of appropriate estimates of extinction and dispersal rates in phylogenetic trees can limit our conclusions about how species richness gradients emerged. With a review of the literature and complemented by an empirical comparison, we show that phylogenetic metrics by itself are not capturing well the speciation, extinction and dispersal processes across the geographical gradients. Furthermore, we show how new biogeographic methods can improve our inference of past events and therefore our conclusions about the evolutionary mechanisms driving regional species richness. Finally, we recommend that future studies include several approaches (e.g., spatial diversification modelling, parametric biogeographic methods) to disentangle the relative the role of speciation, extinction and dispersal in the generation and maintenance of species richness gradients.
Does Pre-Play Social Interaction Improve Negotiation Outcomes?
(RELX Group (Netherlands), 2018) Pablo Brañas‐Garza; Antonio Cabrales; Guillermo Mateu; Sánchez Ángel; Angela Sutan; Angela Sutan