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Gender Equality Policies in STEM in Latin America -- The use of Gray and Systematic Literature Searches
(2023) Indira R. Guzman; José Viterbo; Eunice Pereira dos Santos Nunes; Franci Suni-Lopez; Elizabeth Jiménez; Ana Lara Casagrande
As more actions are needed to reduce the current gap in leadership positions in STEM and IT, it is important to systematically study existing policies and programs that promote gender equality. This research-in-progress (RIP) presents the status of one of the research activities of a larger ongoing project that seeks to advance impact research about women's leadership in STEM fields in low- and middle-income countries (LMICs) in Latin America. Specifically, this study uses two approaches: (a) gray literature search, and (b) systematic literature review search in four recognized citation databases to identify the obtaining crosscountry comparable data to assess policies and interventions to reduce the gender gap in STEM. Researchers and policy makers interested in policies that promote female participation and gender equality will benefit from the results of this study.
Control, dispute, and concentration of land during civil war: Evidence from Colombia
(Taylor & Francis, 2023) José Antonio Fortou; Sandra Lillian Johansson; Juan Carlos Muñoz
How are patterns of armed control and dispute by armed actors related to land concentration, land property rights, and distribution? We argue that armed actors affect land tenure by using different land transfer mechanisms to distribute the land, which reflects the dynamics of control and dispute during civil conflict. We test this argument by studying the case of Urabá, a region in northwestern Colombia, using a mixed-method strategy. First, using extensive qualitative fieldwork, we find that armed actors systematically applied different land transfer mechanisms in areas where they held control. Armed actors strategically changed from employing one land transfer mechanism to another in relation to the level of dispute, political and economic objectives, and alignment with the state, among others. In our fieldwork, we identify how these land transfer mechanisms led to patterns of territorial control and land tenure structure. We then analyze an original dataset of rural plot ownership in Urabá, based on official cadastral information, to empirically verify our qualitative findings. We estimate a village-level fixed effects model that shows that disputed territories and those under paramilitary control had larger plots, higher land inequality, and fewer land transfers. In contrast, territories with established control by left-wing insurgents exhibit a small landholder scheme. These results offer important insights into the relationship between civil armed conflict and land and the logic of rebel governance.¿Cómo se relacionan los patrones de control armado y de disputa por parte de los agentes armados con la concentración de tierras, los derechos de propiedad de las tierras y su distribución? Argumentamos que los agentes armados ejercen un efecto en la tenencia de tierras utilizando diversos mecanismos de transferencia de tierras para distribuir las tierras, lo que refleja la dinámica de control y de disputa durante un conflicto civil. Ponemos a prueba esta hipótesis, utilizando una estrategia de método mixto, a través del estudio del caso de Urabá, una región en el noroeste de Colombia. En primer lugar, hallamos, utilizando un extenso trabajo de campo cualitativo, que los agentes armados aplicaron sistemáticamente diferentes mecanismos de transferencia de tierras en las áreas donde tenían el control. Los agentes armados fueron cambiando, de manera estratégica, el uso entre uno u otro mecanismo de transferencia de tierras en función del nivel de disputa, de los objetivos políticos y económicos, y de la alineación con el Estado, entre otros factores. En nuestro trabajo de campo, identificamos cómo estos mecanismos de transferencia de tierras provocaron patrones de control territorial y de estructura de tenencia de la tierra. A continuación, analizamos un conjunto de datos originales, basado en información catastral oficial, de propiedades parcelarias rurales en Urabá con el fin de verificar empíricamente nuestros hallazgos cualitativos. Estimamos un modelo de efectos fijos en las aldeas que demuestra que los territorios en disputa y aquellos bajo control paramilitar tenían parcelas más grandes, mayor desigualdad de tierras y menor transferencia de tierras. En contraposición, aquellos territorios cuyo control está establecido por insurgentes de izquierdas exhiben un pequeño esquema de terratenientes. Estos resultados ofrecen información importante acerca de la relación entre el conflicto armado civil y la tierra, y acerca de la lógica de la gobernanza rebelde.Quels sont les liens qui unissent les schémas de contrôle armé et de conflits des acteurs armés à la concentration et la distribution des terres, ainsi que les droits à la propriété foncière? Selon nous, les acteurs armés ont une incidence sur le régime foncier en utilisant différents mécanismes de transfert des terres, qui reflètent la dynamique de contrôle et les oppositions lors d’un conflit civil. Afin de vérifier cette hypothèse, nous appliquons une stratégie aux méthodes mixtes pour analyser le cas d’Urabá, une région au nord-ouest de la Colombie. D’abord, à l’aide d’un travail de terrain qualitatif approfondi, nous observons que les acteurs armés ont systématiquement appliqué différents mécanismes de transfert de terres dans les régions qu’ils contrôlaient. Ils passaient stratégiquement d’un mécanisme de transfert des terres à l’autre, notamment selon l’intensité du conflit, les objectifs politiques et économiques ou leur accord avec l’État. Dans notre travail de terrain, nous identifions comment ces mécanismes de transfert de terres ont engendré des schémas de contrôle territorial et une structure de régime foncier. Ensuite, afin de vérifier empiriquement nos observations qualitatives, nous analysons un ensemble de données original de la propriété des parcelles rurales à Urabá, en nous appuyant sur les informations officielles du cadastre. Nous élaborons un modèle des effets fixe au niveau d’un village qui montre que les territoires disputés, et ceux contrôlés par des forces paramilitaires, se caractérisent par de plus grandes parcelles, une inégalité foncière plus marquée et des transferts de terres plus rares. À l’inverse, l’organisation des territoires non disputés et contrôlés par des rebelles de gauche favorise les petits propriétaires terriens. Ces résultats fournissent des renseignements importants sur la relation entre un conflit armé civil, les terres et la logique de gouvernance rebelle.
A climate justice approach to urbanisation processes in the South: Oil axis in Ecuador
(Elsevier BV, 2023) Manuel Bayón; Melissa Moreano Venegas
The Art and Science of Pediatric Tumor Reconstruction Surgery: A Comprehensive Review
(2023) Erick Josue Fabre Morales; César Augusto Guzmán Canaba; Lissette Brigitte Llerena Chicaiza; Dipaola Pamela Pino Vaca; Lenin Stalin Muñoz Villacres; Carlos Alexander Romero Córdova; Hailyn Isabella Villarreal Díaz; Andrea Mishell Rodríguez Coloma; Álvaro Andrés Lucero Carrera
Introduction: pediatric tumor reconstruction surgery stands at the intersection of multiple disciplines, demanding a unique blend of surgical expertise, technological innovation, and a thorough understanding of pediatric oncology. With the evolution of surgical techniques, advanced imaging modalities, and the advent of minimally invasive and robotic surgery, the landscape of pediatric tumor reconstruction has seen substantial transformations.Objective: this review aims to provide a comprehensive overview of the current state and future directions in pediatric tumor reconstruction surgery, shedding light on the art and science of this complex discipline, and outlining the necessity of multidisciplinary collaboration for improved patient outcomes.Methods: a systematic literature search was conducted using PubMed, MEDLINE, and Google Scholar databases with the terms "Pediatric Oncology", "Reconstructive Surgery", "Tumor Surgery", "Minimally Invasive Surgery", "Robotic Surgery", "Surgical Outcomes", and "Quality of Life". The search included articles from 2004-2023. Results: findings from the review reveal a trend towards minimally invasive and robotic surgery, offering the potential for less invasive treatment options and better recovery for patients. Advancements in technology have played a significant role, with photodynamic therapy, near-infrared photoimmunotherapy, and fluorescent-guided surgery providing new tools for local and regional cancer treatment. Conclusions: pediatric tumor reconstruction surgery continues to evolve with advancements in surgical techniques and the integration of innovative technology. The field presents promising future directions, but further research is needed, particularly concerning new treatments, understanding local relapse, and enhancing postoperative quality of life
Principios básicos de rayos X en cirugía de columna. Revisión de la literatura. Equipo Iberolatinoamericano de Investigación SILACO
(2023) Pedro Luis Bazán; Marlene Vanessa Salcido Reyna; José María Jiménez Ávila; Paulo Pereira; Roberto Muscia; Máximo Alberto Diez Ulloa; Luis Miguel Duchén Rodríguez; Cristiano Magalhães Menezes; Andrea Solorio Guerrero; Minerva Gabriela Itriago Gómez
RESUMENEl uso de rayos X es fundamental para la práctica ortopédica, especialmente para la cirugía de columna con enfoques mínimamente invasivos.La radiación se refiere a la transmisión de energía a través de cualquier medio que puede ser transportada como onda o partícula.Los rayos X y la tomografía computarizada utilizan radiación de tipo ionizante.La radiación ionizante es un riesgo potencial tanto para los pacientes como para los profesionales de la salud debido a que puede producir un aumento de radicales libres que provocan anomalías en el ADN celular, lo cual se correlaciona con diversos tipos de cáncer.Los ortopedistas tienen cinco veces más probabilidades de desarrollar cáncer en el transcurso de su vida en comparación con otras áreas del personal de salud, debido a la constante exposición a la radiación ocupacional.La Comisión Internacional de la Protección Radiológica (ICRP) establece tres principios básicos para cumplir sus objetivos: justificación, optimización y límite de dosis.La finalidad principal de la protección radiológica es proporcionar un nivel apropiado de protección para el ser humano, sin limitar indebidamente las prácticas beneficiosas que dan lugar a la exposición de la radiación ionizante.Es muy importante seguir las recomendaciones de protección y mantenimiento de los equipos para reducir en la medida de lo posible la radiación tanto en el personal de la salud como en los pacientes.
Surplus energy in solar home systems as driver for bottom-up grids: When grids emerge from the edge
(2023) Ida Fuchs; Sergio Balderrama; Pedro Crespo del Granado; Sylvain Quoilin; Jayaprakash Rajasekharan
In this paper, surplus energy (SE) from solar home systems (SHS) with energy storage is studied from the perspective of bottom-up grids. The paper addresses two central research questions: 1) How much SE do SHS generate depending on system size parameters and load metrics? and 2) Can SE provide the basis for bottom-up grids in rural swarm electrification? We first analyze different SE profiles for different stochastic demands from three households with various PV and battery system sizes. Next, we analyze how these SE profiles can be used to supply additional households with lower or equal demand. We find that the SE is highly dependent on PV size and cannot be significantly reduced by increasing battery size. Demand profiles with high Peak to Average Power Ratio (PAPR) and low Load at Day Time Ratio (LDTR) are shown to have the highest levels of SE. Simulations show that households with PV and battery system can supply several other households with its SE only. This study shows excellent potential for developing a framework model for bottom-up grids through SHS sizing and bottom-up planning of interconnections in rural communities.
Identifying Plant Physiological and Climatic Drivers in the Woody Shrub Prosopis strombulifera: Effects of Spring Traits on Flower Sprouting and Fruit Production
(Multidisciplinary Digital Publishing Institute, 2023) Felipe S. Carevic; Roberto Contreras; Erico R. Carmona; Ermindo Barrientos
Prosopis strombulifera is a widely distributed woody species distributed along arid ecosystems in America. The interannual evolution of ecophysiological parameters and their effects on fruit production and flower sprouting in Prosopis strombulifera were studied for three years in a natural population distributed in the Atacama Desert. Xylem water column tension, pressure–volume curves, specific leaf area (SLA), and chlorophyll fluorescence parameters were assessed. Flower sprouting was assessed in different weeks using tagged flowers. To assess fruit production, four small containers were placed under twenty-five individuals, allowing the estimation of total annual production and individual production. We found considerable variability between years and between individuals. Positive relationships were found between plant water parameters, SLA, and chlorophyll variables measured in spring at flower sprouting and during fruit production. A negative correlation was found between the mean of the minimum temperatures in spring and flower sprouting. These results suggest that spring ecophysiological parameters strongly affect the reproductive status of P. strombulifera. The results also reflect the potential of this species to adapt to a hyperarid climate by preserving a high relative water content before flower sprouting.
La lucha feminista de Juana Julia Guzmán
(Universidad de Los Andes, 2023) Diana Milena Patiño Niño
The article has a double purpose. The first is to sketch the Colombian and Afro-indigenous leader Juana Julia Guzmán, by circulating some excerpts from the interviews held with her by the Fundación del Caribe team in the archives of the Centro de Documentación Regional Orlando Fals Borda in Montería. This sketch could be considered, in certain aspects, divergent from the one outlined by sociologist Orlando Fals Borda in the fourth volume of his Historia doble de la costa. This forms the basis for the second objective of this article: to explore a feature of Guzmán’s feminism, namely, acuerpamiento or support. The methodology used is strategically plural, close to the multiple ones used in cultural studies. In effect, on the one hand, based on archival work, we will reproduce those parts of Guzmán’s words that contribute to create an image of the actions and some characteristics of her political trajectory, somewhat contradictory and unknown to the general public. To this end, we will also approach the discussions of the researcher Víctor Negrete in his book Origen de las luchas agrarias en Córdoba. On the other hand, and making use of a perspective that we have called mestizo philosophy, we use the tools of hermeneutics to creatively analyze Guzmán’s actions, together with the notion of agreement that finds its origin in the actions of the feminist Lorena Cabnal. Besides providing other coordinates based on which to think about Guzmán’s feminism, different from those of popular feminism that other people have pointed out in her, we hope that this exercise will also reveal the complexity of this leader, whose political actions were not inevitable, nor were they the product of the deprivation into which she was born and raised, but were determined by situations and decisions, such as supporting the political actions of others different from her.
Two new species of the ant-like spider genus Fluda Peckham &amp; Peckham, 1892 from Bolivia with first reports of potential ant models for the genus and a novel ant-resembling behavior (Araneae: Salticidae, Simonellini)
(Q15088586, 2023) Robert Perger; Gonzalo D. Rubio
In this work, the results of a survey for species of Fluda Peckham & Peckham, 1892 in primary forest in five Bolivian forest ecoregions are reported. Fluda dauca sp. nov. is described from Southwest Amazon forest and F. thuruampara sp. nov. from Bolivian Yungas forest. Fluda perdita (Peckham & Peckham, 1892) is reported from Bolivia for the first time. Both new species exhibited polymorphic mimicry; dark females of both species resembled the turtle ant Cephalotes pusillus (Klug, 1824) and dark males of F. thuruampara sp. nov. the carpenter ant Camponotus sanctaefidei Dalla Torre, 1892. Orange males and females of F. dauca sp. nov. are likely mimics of Camponotus latangulus Roger, 1863. Males of Fluda may compensate lower mimetic accuracy by the broadened femora I, resembling an ant head in lateral view and ant mandibles when moving the face towards a potential threat. As in other Simonellini, the turnover of Fluda species between the South American superregions suggests that significant shifts in seasonality and related conditions are major factors triggering speciation in the tribe Simonellini.
A Machine Learning Approach for Bitcoin Forecasting
(2023) Stefano Sossi-Rojas; Gissel Velarde; Damian Zięba
Bitcoin is one of the cryptocurrencies that has gained popularity in recent years. Previous studies have shown that closing price alone is not enough to forecast its future level, and other price-related features are necessary to improve forecast accuracy. We introduce a new set of time series and demonstrate that a subset is necessary to improve directional accuracy based on a machine learning ensemble. In our experiments, we study which time series and machine learning algorithms deliver the best results. We found that the most relevant time series that contribute to improving directional accuracy are open, high, and low, with the largest contribution of low in combination with an ensemble of a gated recurrent unit network and a baseline forecast. The relevance of other Bitcoin-related features that are not price-related is negligible. The proposed method delivers similar performance to the state of the art when observing directional accuracy.
Tropical tropospheric aerosol sources and chemical composition observed at high-altitude in the Bolivian Andes
(2023) Isabel Moreno; Radovan Krejčí; Jean‐Luc Jaffrezo; Gaëlle Uzu; Andrés Alástuey; Marcos Andrade; Valeria Mardóñez; Alkuin Maximilian Koenig; Diego Aliaga; Claudia Mohr
Abstract. The chemical composition of PM10 and PM2.5 was studied at the summit of Mt. Chacaltaya (5380 masl, lat.-16.346950º, lon. -68.128250º) providing a unique long-term record spanning from December 2011 to March 2020. The chemical composition of aerosol at the Chacaltaya GAW site is representative of the regional background, seasonally affected by biomass burning practices and by nearby anthropogenic emissions from the metropolitan area of La Paz – El Alto. Concentration levels are clearly influenced by seasons with minimum occurring during the wet season (December to March) and maxima occurring during the dry and transition seasons (April to November). Ions, total carbon (EC+OC) and saccharide concentrations range between 558–1785, 384–1120 and 4.3–25.5 ng m-3 for bulk PM10 and 917–2308, 519–1175 and 3.9–24.1 ng m-3 for PM2.5, respectively. Such concentrations are overall lower compared to other high-altitude stations around the globe, but higher than Amazonian remote sites (except for OC). For PM10, there is dominance of insoluble mineral matter (33–56 % of the mass), organic matter (7–34 %) and secondary inorganic aerosol (15–26 %). Chemical composition profiles were identified for different origins: EC, NO3-, NH4+, glucose, C2O4-2 for the nearby urban and rural areas; OC, EC, NO3-, K+, acetate, formiate, levoglucosan, some F- and Br- for biomass burning; MeSO3-, Na+, Mg2+, Br- for aged marine emissions from the Pacific Ocean; arabitol, mannitol, K+ for biogenic emissions; Na+, Ca2+, Mg2+ for soil dust, and SO42-, F-, and some Cl- for volcanism. Regional biomass-burning practices influence the soluble fraction of the aerosol particularly between July and September. The organic fraction is present all year round and has both anthropogenic (biomass burning and other combustion sources) and natural (primary and secondary biogenic emissions) origins, with the OC/EC mass ratio being practically constant all year round (10.5±38.9). Peruvian volcanism dominates the SO42- concentration since 2014, though it presents a strong temporal variability due to the intermittence of the sources and seasonal changes on the transport patterns. These measurements represent some of the first long-term observations of aerosol chemical composition at a continental high-altitude site in the tropical Southern hemisphere.
Assessing generalizability of an AI-based visual test for cervical cancer screening
(2023) Syed Rakin Ahmed; Didem Egemen; Brian Befano; Ana Cecilia Rodríguez; José Jerónimo; Kanan Desai; Carolina Terán; Karla Alfaro; Joël Fokom Domgue; Kittipat Charoenkwan
ABSTRACT A number of challenges hinder artificial intelligence (AI) models from effective clinical translation. Foremost among these challenges are: (1) reproducibility or repeatability, which is defined as the ability of a model to make consistent predictions on repeat images from the same patient taken under identical conditions; (2) the presence of clinical uncertainty or the equivocal nature of certain pathologies, which needs to be acknowledged in order to effectively, accurately and meaningfully separate true normal from true disease cases; and (3) lack of portability or generalizability, which leads AI model performance to differ across axes of data heterogeneity. We recently investigated the development of an AI pipeline on digital images of the cervix, utilizing a multi-heterogeneous dataset (“SEED”) of 9,462 women (17,013 images) and a multi-stage model selection and optimization approach, to generate a diagnostic classifier able to classify images of the cervix into “normal”, “indeterminate” and “precancer/cancer” (denoted as “precancer+”) categories. In this work, we investigated the performance of this multiclass classifier on external data (“EXT”) not utilized in training and internal validation, to assess the portability of the classifier when moving to new settings. We assessed both the repeatability and classification performance of our classifier across the two axes of heterogeneity present in our dataset: image capture device and geography, utilizing both out-of-the-box inference and retraining with “EXT”. Our results indicate strong repeatability of our multiclass model utilizing Monte-Carlo (MC) dropout, which carries over well to “EXT” (95% limit of agreement range = 0.2 - 0.4) even in the absence of retraining, as well as strong classification performance of our model on “EXT” that is achieved with retraining (% extreme misclassifications = 4.0% for n = 26 “EXT” individuals added to “SEED” in a 2n normal : 2n indeterminate : n precancer+ ratio), and incremental improvement of performance following retraining with images from additional individuals. We additionally find that device-level heterogeneity affects our model performance more than geography-level heterogeneity. Our work supports both (1) the development of comprehensively designed AI pipelines, with design strategies incorporating multiclass ground truth and MC dropout, on multi-heterogeneous data that are specifically optimized to improve repeatability, accuracy, and risk stratification; and (2) the need for optimized retraining approaches that address data heterogeneity (e.g., when moving to a new device) to facilitate effective use of AI models in new settings. AUTHOR SUMMARY Artificial intelligence (AI) model robustness has emerged as a pressing issue, particularly in medicine, where model deployment requires rigorous standards of approval. In the context of this work, model robustness refers to both the reproducibility of model predictions across repeat images, as well as the portability of model performance to external data. Real world clinical data is often heterogeneous across multiple axes, with distribution shifts in one or more of these axes often being the norm. Current deep learning (DL) models for cervical cancer and in other domains exhibit poor repeatability and overfitting, and frequently fail when evaluated on external data. As recently as March 2023, the FDA issued a draft guidance on effective implementation of AI/DL models, proposing the need for adapting models to data distribution shifts. To surmount known concerns, we conducted a thorough investigation of the generalizability of a deep learning model for cervical cancer screening, utilizing the distribution shifts present in our large, multi-heterogenous dataset. We highlight optimized strategies to adapt an AI-based clinical test, which in our case was a cervical cancer screening triage test, to external data from a new setting. Given the severe clinical burden of cervical cancer, and the fact that existing screening approaches, such as visual inspection with acetic acid (VIA), are unreliable, inaccurate, and invasive, there is a critical need for an automated, AI-based pipeline that can more consistently evaluate cervical lesions in a minimally invasive fashion. Our work represents one of the first efforts at generating and externally validating a cervical cancer diagnostic classifier that is reliable, consistent, accurate, and clinically translatable, in order to triage women into appropriate risk categories.
Workflows Community Summit 2022: A Roadmap Revolution
(Cornell University, 2023) Rafael Ferreira da Silva; Rosa M. Badía; Venkat Bala; Debbie Bard; Peer‐Timo Bremer; Ian K. Buckley; Silvina Caíno‐Lores; Kyle Chard; Carole Goble; Shantenu Jha
Scientific workflows have become integral tools in broad scientific computing use cases. Science discovery is increasingly dependent on workflows to orchestrate large and complex scientific experiments that range from execution of a cloud-based data preprocessing pipeline to multi-facility instrument-to-edge-to-HPC computational workflows. Given the changing landscape of scientific computing and the evolving needs of emerging scientific applications, it is paramount that the development of novel scientific workflows and system functionalities seek to increase the efficiency, resilience, and pervasiveness of existing systems and applications. Specifically, the proliferation of machine learning/artificial intelligence (ML/AI) workflows, need for processing large scale datasets produced by instruments at the edge, intensification of near real-time data processing, support for long-term experiment campaigns, and emergence of quantum computing as an adjunct to HPC, have significantly changed the functional and operational requirements of workflow systems. Workflow systems now need to, for example, support data streams from the edge-to-cloud-to-HPC enable the management of many small-sized files, allow data reduction while ensuring high accuracy, orchestrate distributed services (workflows, instruments, data movement, provenance, publication, etc.) across computing and user facilities, among others. Further, to accelerate science, it is also necessary that these systems implement specifications/standards and APIs for seamless (horizontal and vertical) integration between systems and applications, as well as enabling the publication of workflows and their associated products according to the FAIR principles. This document reports on discussions and findings from the 2022 international edition of the Workflows Community Summit that took place on November 29 and 30, 2022.
Unravelling large-scale patterns and drivers of biodiversity in dry rivers
(2023) Arnaud Foulquier; Thibault Datry; Roland Corti; Daniel von Schiller; Klement Tockner; Rachel Stubbington; Mark O. Gessner; Frédéric Boyer; Marc Ohlmann; Wilfried Thuiller
<title>Abstract</title> The lack of data from non-perennial rivers, which regularly cease to flow and dry up, poses a significant challenge in understanding river biodiversity. These dynamic ecosystems, accounting for over half of the global river network, remain understudied. To address this gap, we conducted a coordinated experiment and a metabarcoding approach on environmental DNA targeting multiple taxa (i.e. Archaea, Bacteria, Fungi, Algae, Protozoa, Nematoda, Arthropoda and Streptophyta). Dry sediments were collected from 84 non-perennial rivers across 19 countries on five continents to investigate biodiversity patterns and drivers. Our findings reveal that both direct (e.g., nutrient and carbon availability) and indirect (e.g., latitude and climate) drivers significantly influence local biodiversity for most taxa. In particular, we observed that low resource availability and extended dry phases promote the prevalence of oligotrophic microbial taxa, similar to soil microbial communities during drought events. Interestingly, our inferred partial correlation networks indicate that covariation among taxa, particularly Bacteria, Fungi, Algae, and Protozoa, plays a more substantial role in explaining variations in community composition than abiotic gradients. This unexpected result suggests that biotic interactions may drive community assembly in non-perennial rivers, potentially shaping biodiversity responses in the face of global changes like warming and altered hydrological patterns.
Natural Biocontrol of Athelia rolfsii isolate INVEPAR-05 in Stevia rebaudiana Bertoni: Exploring the Biocontrol Potential of Native Trichoderma spp. Strains
(2023) Luis Alfonso Rodríguéz-Páez; Juán de Diós Jaraba-Navas; Yirlis Yadeth Pineda‐Rodríguez; Mauricio Begambre-Hernandez; Marcelo F. Pompelli; Ana Melisa Jimenez-Ramirez; Anselmo Gil-Rocha; Alfredo Jarma‐Orozco; Enrique Combatt Caballero; Katia Aviña‐Padilla
Stevia rebaudiana (Bert.) is a natural sweetener with diterpenic glycosides, offering 300 times more sweetness than sucrose, and boasting low-calorie content, along with medicinal and therapeutic properties. To address a limited genetic diversity, a germplasm bank comprising 115 segregated lines of stevia was established in Colombia. Notwithstanding, the fungus Athelia rolfsii adversely impacted key stevia lines, leading to wilting and plant mortality. For this reason our study aimed to explore the biocontrol potential of native strains of Trichoderma spp., isolated from productive lots in Colombia's Cordoba department, as a solution to manage A. rolfsii. Soil samples underwent serial dilution technique (103 conidia.mL-1) to obtain Trichoderma spp. isolates, which were thoroughly morphologically and molecularly characterized. A total five native strains were identified through sequencing the PCR products using universal ITS primers, and comparisons with the GENBANK database confirmed their identity (OK310695.1, ON237703.1, ON238106.1, ON237737.1, and ON237923.1). Their biocontrol efficacy against A. rolfsii was evaluated using the dual culture technique. Remarkably, all strains exhibited significant biocontrol capacity against the A. rolfsii isolate INVEPAR-05 (OK271308.1), except for Trichoderma viride INVEPAR-T10 (ON237923.1). These findings suggest that Trichoderma spp. could be a potential option to manage the fungus in stevia.
Tailoring evidence into action: using a codesign approach for biodiversity information in the Tropical Andes
(2023) Jose W. Valdez; Henrique M. Pereira; Gustavo Francisco Morejón; Cristina Acosta‐Muñoz; Francisco Javier Bonet García; Lucía Castro Vergara; Claros R. Xavier; Michael Gill; Carmen Josse; Indyra Lafuente‐Cartagena
Abstract Biodiversity conservation is a complex and transdisciplinary problem that requires engagement and cooperation among scientific, societal, economic, and political institutions. However, historical approaches have often failed to bring together and address the needs of relevant stakeholders in decision-making processes. The Tropical Andes, a biodiversity hotspot where conservation efforts often conflict with socioeconomic issues and policies that prioritize economic development, provides an ideal model to develop and implement more effective approaches. In this study, we present a codesign approach that mainstreams and improves the flow of biodiversity information in the Tropical Andes, while creating tailored outputs that meet the needs of economic and societal stakeholders. We employed a consultative process that brought together biodiversity information users and producers at the local, national, and regional levels through a combination of surveys and workshops. This approach identified priority needs and limitations of the flow of biodiversity information in the region, which led to the co-design of user-relevant biodiversity indicators. By leveraging the existing capacities of biodiversity information users and producers, we were able to co-design multiple biodiversity indicators and prioritize two for full implementation ensuring that the data was findable, accessible, interoperable, and reusable based on the FAIR principles. This approach helped address limitations that were identified in the stakeholder engagement process, including gaps in data availability and the need for more accessible biodiversity information. Additionally, capacity-building workshops were incorporated for all stakeholders involved, which aimed to not only improve the current flow of biodiversity information in the region but also facilitate its future sustainability. Our approach can serve as a valuable blueprint for mainstreaming biodiversity information and making it more inclusive in the future, especially considering the diverse worldviews, values, and knowledge systems between science, policy, and practice.
Appendiceal Phlegmon as an intraoperative finding: A retrospective analysis
(Research Square (United States), 2023) Danny Conde; Lina Rodríguez; David Venegas; C. Rey; Ricardo E. Núñez-Rocha; Ricardo Nassar; Marco Vanegas; Catalina Monsalve; Pablo Pinzón; Felipe Girón
Abstract Background Emergency procedures due to acute surgical abdomen correspond to a great part of emergency surgeries. Appendicitis is the most common abdominal surgical emergency in the world. Intraoperative findings can represent a challenging scenario for the surgical team and its decisions. Appendiceal phlegmon/plastron presents in 3.8-7% of patients with appendicitis and can be considered as a challenging surgical scenario where expertise may gain a fundamental value in terms of decision-making process. Therefore, we present clinical courses and outcomes of 40 patients that underwent emergency surgery with these intraoperative findings from 2016 to 2018. Methods Retrospective study with a prospective database in which we described patients with emergent need for surgical procedure due to peritoneal signs with surgical findings of appendiceal phlegmon. Multivariate analysis was performed to prove the relationship between obesity, diabetes, and surgeon experience with any complication and colonic resection. Results 40 patients underwent surgical procedure due to peritoneal signs with intraoperative findings of appendiceal phlegmon. Mean age was 51.9 (± 20.4). Procedures were performed based on intraoperative findings being appendectomy the most frequent (85%), followed by right hemicolectomy (10%) and partial cecum resection (5%). Three patients required reintervention. No mortalities were documented. Surgeries performed by junior surgeons have a higher probability to require colonic resections (P = 0.05, OR 4.05 ,95% CI), also obesity is associated with complications (P = 0.04, OR 1.44, 95% CI). Conclusion Finding of appendiceal phlegmon constitute a challenging surgical scenario in daily practice. Our patient’s complication rates are similar to those described in literature despite its emergent circumstances. Surgeons' expertise appears to be associated with outcomes. Further studies are needed to give clear recommendations.
Etiology of Acute Febrile Illness in the Peruvian Amazon as determined by modular formatted quantitative PCR: A Protocol for RIVERA, a Health Facility-Based Case-Control Study
(Research Square (United States), 2023) Pablo Peñataro Yori; Maribel Paredes Olórtegui; Francesca Schiaffino; Karin Perez; Greisi Curico Huansi; Thomas G. Flynn; Jixian Zhang; Cesar Ramal Asayag; Graciela Meza‐Sánchez; Hermann Silva Delgado
Project 1791, Registro de Proyectos de Investigación en Salud Pública (PRISA), Instituto Nacional de Salud, Perú.
Aging and putative frailty biomarkers are altered by spaceflight
(2023) Andrea Camera; Marshall Tabetah; Verónica Castañeda; JangKeun Kim; Aman Singh; Alissen Haro-Vinueza; Ivonne Salinas; Allen Seylani; Shehbeel Arif; Saswati Das
<title>Abstract</title> Human space exploration is hazardous, causing molecular changes that can alter astronauts' health. This can include genomic instability, mitochondrial dysfunction, increased inflammation, homeostatic dysregulation, and epigenomic changes. These alterations are similar to changes during aging on Earth. However, little is known about the link between these changes and disease development in space. Frailty syndrome is a robust predictor associated with biological aging, however its existence during spaceflight has not been examined. We used murine data from NASA’s GeneLab and astronaut data from JAXA and Inspiration4 missions to evaluate the presence of biological markers and pathways related to frailty, aging and sarcopenia. We identified changes in gene expression that could be related to the development of a frailty-like condition. These results suggest that the parallels between spaceflight and aging may extend to frailty as well. Future studies examining the utility of a frailty index in monitoring astronaut health appear warranted.
Parasite hybridization promotes spreading of endosymbiotic viruses
(2023) Senne Heeren; Ilse Maes; Mandy Sanders; Lon‐Fye Lye; Jorge Arévalo; Alejandro Llanos‐Cuentas; Lineth García; Philippe Lemey; Stephen M. Beverley; James A. Cotton
Viruses are the most abundant biological entities on Earth and play a significant role in the evolution of many organisms and ecosystems. In pathogenic protozoa, the presence of endosymbiotic viruses has been linked to an increased risk of treatment failure and severe clinical outcome. Here, we studied the molecular epidemiology of the zoonotic disease cutaneous leishmaniasis in Peru and Bolivia through a joint evolutionary analysis of Leishmania braziliensis parasites and their endosymbiotic Leishmania RNA virus. We show that parasite populations circulate in isolated pockets of suitable habitat and are associated with single viral lineages that appear in low prevalence. In contrast, groups of hybrid parasites were geographically and ecologically dispersed, and commonly infected from a pool of genetically diverse viruses. Our results suggest that parasite hybridization, likely due to increased human migration and ecological perturbations, increased the frequency of endosymbiotic interactions known to play a key role in disease severity.