Search Results (634)

Live case studies are widely used in higher education to support active learning; however, their pedagogical potential is often limited by weak integration with learning theories and assessments. This research-to-practice study examines the systematic design of live case studies by integrating Kolb’s experiential learning cycle (ELC) and authentic assessment (AA) principles. This paper presents a framework that conceptualises live cases as the learning context, ELC as the learning process, and AA as evaluative logic. The framework is illustrated through a case study of an undergraduate Quality Management module in industrial engineering at a Mexican university, involving 31 final-year students. The study is design-oriented and illustrative, aiming to demonstrate framework enactment rather than evaluating causal effectiveness. Using a case study methodology, the instructional design and enactment were documented using the ADDIE model. Data were obtained from educational artefacts, assessment results, and student feedback surveys. The findings suggest that aligning teaching and assessment activities with the ELC stages and the AA principles effectively supports learning trajectories. This support covers experience, reflection, conceptualisation, and application. Live case studies enabled the integration of multiple assessment methods around shared organisational problems and supported personalised learning through students’ case selection. This study contributes a design logic and operational framework for distributing authentic assessment across Kolb’s experiential learning stages within live case pedagogy. Rather than offering statistical generalisation, the framework serves as a foundation for adaptation and research, emphasising transferability across disciplines, educational levels, and delivery modes. Limitations are acknowledged regarding the conceptual scope, methodological design, and empirical context. Full article

Chapare virus (CHAPV) is an Arenaviridae family member and causative agent of Chapare hemorrhagic fever (CHHF). Endemic to Bolivia, CHAPV was found to be the cause of several outbreaks of CHHF in Bolivia in 2003 and 2019 with high case-fatality rates and instances of human-to-human transmission. The pathogenesis of CHAPV infection is poorly understood, and no vaccines or antivirals are available, in part due to a dearth of available animal models. Mice lacking signal transducer and activator of transcription 1 (STAT1^-/-) have been shown to succumb to infection by related arenaviruses, including Machupo virus, and were investigated for their susceptibility to CHAPV infection. Challenge with CHAPV resulted in partial lethality in STAT1^-/- mice with a biphasic disease course characterized by initial viral load and pathology in the spleen and liver followed by inflammation and high viral titers in the brain and spinal cord that immediately preceded mortality. Adaptation in the brains of STAT1^-/- mice resulted in a fully lethal mouse-adapted CHAPV variant, with a similar biphasic disease course, but virus in tissues was detected more proximal to challenge. The result of this study is a lethal small-animal rodent model for CHAPV that recapitulates many aspects of human CHAPV disease. Full article

Heavy metal pollution from mining activities and urban runoff poses a serious threat to public health and aquatic ecosystems in vulnerable communities around the Bolivia–Peru transboundary Lake Titicaca basin. This study evaluates the use of two abundant wetland plants—totora (Schoenoplectus californicus) and reed (Phragmites australis)—as low-cost, locally available biosorbents for the removal of dissolved iron (Fe²⁺) from the Pallina River, a major contaminant source to Cohana Bay. Monitoring data from Bolivia’s Ministry of Environment and Water (2019–2022) revealed Fe²⁺ concentrations exceeding the national legal limit (0.3 mg/L) by more than 20 times during the dry season. Laboratory experiments using synthetic Fe²⁺ solutions (20 mg/L) optimized biosorption conditions, identifying pH 5, 4–6 g/L biomass, fine particle size (0.15–0.212 mm), and a 3 h contact time as optimal. Both plants followed pseudo-second-order kinetics and Langmuir isotherms. Totora showed superior performance, achieving a maximum capacity of 7.8 mg/g compared to reed’s 2.9 mg/g. Continuous-flow column tests removed up to 95% of Fe²⁺ from synthetic water. When applied to real Pallina River water, totora achieved 50% Fe²⁺ removal despite reduced efficiency due to competing organic matter. The findings demonstrate the potential of totora-based biosorption as a scalable, nature-based solution for transboundary water management. The policy implications of this study are profound under the national and global water and wetland governance mechanisms and transboundary frameworks like the Binational Autonomous Authority of Lake Titicaca (ALT, est. 1996) and Ramsar Convention. Full article

Bolivia is home to approximately 20% of the tropical glaciers in South America, which are sensitive indicators of climate change and critical water resources. Glaciers in the Cordillera Real supply meltwater to Bolivia’s administrative capital, La Paz, making it important to accurately assess their evolution. This study reassesses the trajectory of glacier loss in the Cordillera Real between 1992 and 2024. We construct a time-evolving glacier inventory utilizing remote sensing data (Landsat) and techniques to limit the impact of ephemeral snow cover. Our inventory is at a temporal resolution (5- to 8-year spacing) that allows us to assess the trajectory of glacier loss using statistical models. Between 1992 and 2024, the Cordillera Real lost 103.67 ± 9.97 km² of glacierized area, representing a 42.0 ± 2.1% reduction. We find that glaciers in the Cordillera Real have been retreating at a constant absolute loss rate of 2.99 [2.32, 3.67] km² yr⁻¹ and a constant fractional loss rate of 1.6 [1.3, 1.9]% yr⁻¹, contrasting with past studies that suggest accelerating or decelerating loss rates. Our findings provide new insights into the current extent of glaciers in the Cordillera Real and their longevity. The time-evolving inventory is available for use in future studies on the evolution of glaciers in the Cordillera Real and the impacts of their continued loss. Full article

Chagas disease remains a major public health concern in Latin America, with Bolivia reporting one of the highest burdens of infection. While congenital transmission has become the predominant route of new infections in several countries, vector-borne transmission persists in rural and peri-urban regions. Postrervalle, in the department of Santa Cruz, is officially classified as a low-infestation area; however, updated community-level data remain limited. We conducted a cross-sectional study in July 2023 involving 58 mothers and 104 of their children in Postrervalle. Participants underwent serological screening with three diagnostic assays, and epidemiological data were collected via structured maternal questionnaires. Logistic regression models were used to assess associations between child Trypanosoma cruzi seropositivity and maternal or household exposures during pregnancy. Seroprevalence was 15.5% among mothers and 3.8% among children. Notably, all seropositive children were born to mothers who tested seronegative, suggesting non-congenital transmission. In multivariable analysis, living in houses with mud walls during pregnancy was strongly associated with child seropositivity (adjusted OR = 38.566), while older child age also increased the odds of infection. Other maternal exposure variables showed elevated but imprecise associations. Despite its classification as a low-infestation area, Postrervalle shows serological patterns consistent with postnatal acquisition linked to domestic structural conditions that facilitate triatomine colonization. These findings overall highlight the need for integrated serological and entomological surveillance to better characterize and prevent Chagas transmission in rural communities. Full article

The notion of complex thinking has become established as an essential competency for understanding multidimensional social phenomena and for engaging with democratic processes in diverse contexts. This study examined within-individual changes associated with participation in an educational intervention aimed at developing complex thinking among university students in Bolivia, Chile, Colombia, and Mexico, and explored their implications for intercultural citizenship education. A quasi-experimental pretest–posttest design was employed, drawing on panel data and fixed-effects regression models to estimate intraindividual variation over time, complemented by an exploratory differential analysis by sex. The findings revealed statistically significant within-individual changes across the four evaluated subdimensions, as well as differentiated patterns by sex, with women showing higher relative changes in critical and innovative thinking and men showing higher relative changes in scientific reasoning. Interpreted in dialogue with existing literature, these observed changes in complex thinking are consistent with theoretical frameworks that conceptualize such competencies as relevant cognitive foundations for intercultural citizenship. Overall, the study provides empirically grounded insights into the role of complexity-oriented learning experiences in higher education in Latin America and outlines considerations for the design of more context-sensitive and equity-oriented educational initiatives. Full article

Community-based tourism (CBT) is widely promoted as a route to inclusive growth and conservation in emerging economies, yet outcomes vary because the communities’ ability to create, scale, and sustain CBT enterprises depends on the surrounding entrepreneurial ecosystem. Building on entrepreneurial ecosystem theory and grand challenges scholarship, this article reframes CBT as a place-based entrepreneurial ecosystem that mobilizes local and external actors, resources, and institutions to advance the United Nations 2030 Agenda. The purpose of the study is to develop and illustrate an SDG-oriented CBT entrepreneurial ecosystem framework and identify the ecosystem mechanisms and boundary conditions associated with SDG contributions. Using a qualitative multiple-case design and structured document analysis of 42 public artifacts (peer-reviewed studies, program evaluations, organizational reports, and organizational webpages), three initiatives were examined: Namibia’s communal conservancies, Chi Phat community-based ecotourism in Cambodia, and Bolivia’s Chalalán Ecolodge. Cross-case synthesis showed that progress on SDG 1 (No Poverty) and SDG 8 (Decent Work and Economic Growth)—with complementary contributions to SDGs 10, 11, 12, 15, 16, and 17—emerges when ecosystems combine: (i) enforceable community rights and benefit-sharing rules; (ii) bridging organizations that provide training, finance, market access, and quality assurance; (iii) accountable local governance for transparency and conflict resolution; and (iv) reinvestment mechanisms that fund conservation and community services. The analysis also identified boundary conditions (e.g., elite capture, value leakage, donor dependence, uneven tourism potential, and demand shocks) and specific policy levers (tenure security, adaptive concession policies, blended finance, and impact monitoring) to strengthen CBT ecosystems for SDG delivery. Full article

West Nile virus (WNV) is a mosquito-borne flavivirus with one of the widest global distributions. Since its discovery in Uganda in 1937, it has become a major zoonotic pathogen, and after its introduction into the United States in 1999, it spread rapidly across the Americas, becoming the leading cause of neuroinvasive arboviral disease. Its expansion illustrates a remarkable ecological adaptability, further intensified by climate change. In Latin America and the Caribbean, WNV circulation has been consistently documented in birds, horses, and mosquitoes; however, confirmed human cases remain disproportionately scarce compared with North America and Europe. Reports include sporadic human cases in Brazil (>100 since 2014), Mexico (~13), Argentina (2006–2007), Puerto Rico (2007), Nicaragua, and Haiti, while animal and vector evidence extends to Guatemala, El Salvador, Belize, Costa Rica, Bolivia, Paraguay, Colombia, Venezuela, Cuba, and Ecuador. This paradox likely reflects structural limitations within regional health systems, including underdiagnosis, restricted diagnostic capacity, and significant surveillance gaps, particularly in contexts where mild febrile syndromes may be misclassified as dengue, Zika, or Chikungunya. The regional risk of emergence is further amplified by climatic variability, ecological change, and intensifying human–wildlife interactions. Experiences from Europe highlight the importance of early detection, transfusion safety, and integrated surveillance within a One Health framework. Strengthening preparedness in Latin America will require investments in diagnostic infrastructure, implementation of standardized seroepidemiological surveys, development of predictive models tailored to local ecological contexts, and robust intersectoral collaboration. Full article

Children living in resource-limited regions with inadequate environmental sanitation, such as the Bolivian highlands, are affected by parasitic infections that may compromise nutritional status. Objective: This study aimed to assess the prevalence of intestinal parasitic infections and their associations with nutritional status, micronutrient deficiencies, and anemia in school-aged children from La Paz, Bolivia. Methods: A cross-sectional study was conducted among 212 schoolchildren aged 5–13 years in the municipality of La Paz, in highland areas characterized by high poverty levels. Parasitological examination, anthropometric measurements, and biochemical assessment of micronutrients (vitamins A and D, zinc, iron) were performed to evaluate children’s health status. Results: Mild malnutrition was more prevalent than moderate-to-severe forms. Micronutrient analysis revealed substantial deficiencies in vitamin A (39%), zinc (25%), and vitamin D (18%). Zinc deficiency was significantly more common in children aged 11–13 years compared to younger age groups (p = 0.034). Intestinal protozoan infections showed significant associations with micronutrient deficiencies. Giardia lamblia infection was associated with both vitamin A (30.9%, p = 0.042) and vitamin D (78.9%, p = 0.001) deficiencies. Blastocystis spp. infection was similarly linked to higher prevalence of vitamin A (35.8%, p = 0.025) and vitamin D (69.7%, p = 0.004) deficiencies. Entamoeba coli infection was significantly associated with vitamin D deficiency (p = 0.021), while Iodamoeba bütschlii infection showed a significant association with zinc status (p = 0.027), with notably lower zinc deficiency prevalence in infected children (7.7%) compared to non-infected children. Among helminth infections, Ascaris lumbricoides was significantly associated with vitamin D deficiency (37%, p = 0.018). Moderate-to-severe anemia was highly prevalent, affecting over half of the children regardless of sex. Wasting (BAZ) was significantly associated with age (p = 0.030), with moderate-to-severe cases most prevalent in children aged 5–7 years and absent in older groups, while mild wasting increased with age. In univariate logistic regression analysis, zinc deficiency emerged as a significant risk factor for anemia (OR = 2.51, 95% CI: 1.19–5.29, p = 0.016). No significant associations were observed between anemia and sex, age group, vitamin A or D status, or anthropometric indicators including underweight, stunting, or wasting. Conclusions: These findings highlight the substantial burden of micronutrient deficiencies, parasitic infections, and anemia among children in this impoverished region, underscoring the urgent need for targeted public health interventions addressing nutritional supplementation, parasite control, and improved sanitation. Full article

At least seven species of wild cats inhabit Colombia, and these species are also distributed throughout Mexico, Central America, and the rest of South America (jaguar, puma, jaguarundi, ocelot, margay, tigrina, and Pampas cat). A checklist and review of phylogeographic and population genetic studies on these seven wild cat species has been conducted here, as this information is vital for effective conservation programs. The jaguar is the feline species on which the most population genetic studies have been carried out in the Neotropics. In general, little genetic structure has been found at a macro-geographic scale. Genetic diversity is high in countries such as Colombia, Peru, and Bolivia, and generally throughout the Amazon basin. However, genetic diversity is more moderate or even significantly lower in Mexico and the Brazilian Atlantic Forest. Much of the genetic research on the jaguar has focused on Brazil, Mexico, and Belize, but Colombia is also very well represented in these studies. However, there is a complete or very pronounced lack of data in other areas such as Venezuela, the Guianas, some Central American countries, Paraguay, and northern Argentina. After the jaguar, the most studied feline in Neotropics from a population genetics perspective is the puma. In North America, this species has low genetic diversity, while the diversity in Central America is moderate, and South America is where genetic diversity is highest. The countries best represented in these studies are Brazil (southern of the country), Mexico, Belize, and Argentina. However, countries like Colombia, Ecuador, Peru, and Paraguay are very poorly represented in puma genetic studies. Very few genetic studies have been conducted on the jaguarundi, despite its vast geographic distribution. In northern Mexico, its genetic diversity is very low, but in countries like Colombia, Peru, and Bolivia, genetic diversity is very high. Colombia is probably the country where jaguarundis have been genetically studied most extensively. The third wild cat species with the most molecular studies in Neotropics is the ocelot, although it lags considerably behind jaguars and pumas. Its genetic diversity is low in Texas and northern Mexico, but very high, especially in countries surrounding the Amazon basin. A good number of macro-geographic studies have been conducted on the ocelot, and these studies are very representative of ocelots in countries such as Colombia (probably the best represented country), Ecuador, Peru, Bolivia, Panama, and Costa Rica. However, there are other countries where molecular studies of the ocelot have not been carried out, such as Paraguay and Argentina, with the lack of such studies in Brazil being particularly noteworthy. Very few molecular studies have been conducted on the margay. In general, its genetic diversity is very high in all the studies performed. Colombia, Peru and Bolivia are very well represented, but the lack of molecular studies in Mexico, much of Central America, and South American countries such as Brazil, Paraguay, and Argentina is striking. The tigrina is one of the Neotropical wild cat species that requires the most molecular studies to unravel its complex systematics. Only the southern Brazilian tigrina (Leopardus guttulus), which was elevated to a new species, has generated comprehensive molecular information. Molecular studies of the Andean tigrina have revealed a very complex picture that, at present, does not allow us to know exactly how many species or taxa inhabit that area of South America and, therefore, to develop a conservation program that adequately correlates with that number of taxa. Finally, in the case of the Pampas cat, molecular studies are well represented with specimens from Peru, Bolivia, Chile, Argentina, Brazil and Uruguay. Studies are needed in Paraguay, and especially in Ecuador and southern Colombia (assuming a stable population of Pampas cats exists in the latter country), where even at the molecular level, the specific taxon (one species or five species) present has not yet been determined. All this information is essential for developing effective regional and global conservation programs for these magnificent creatures. In Colombia, the development of molecular studies with the puma, the tigrina, and the Pampas cat is of special interest. Full article

To improve crop yields and incomes, farmers consistently adapt their practices to climate and market fluctuations, resulting in highly variable crop field distribution and coverage in space and time. As these dynamics illustrate farmers’ challenges, up-to-date crop-type mapping is essential for understanding farmers’ needs and supporting their adoption of sustainable practices. With global coverage and frequent temporal observations, remote sensing data are generally integrated into machine learning models to monitor crop dynamics. Unlike physical-based models that rely on straightforward use, implementing machine learning models requires extensive user interaction. In this context, this study assesses how sensitive the models’ outputs are to feature selection and hyperparameter tuning, as both processes rely on user judgment. To achieve this, Sentinel-1 (S1) and Sentinel-2 (S2) features are integrated into five distinct models (Random Forest (RF), Support Vector Machine (SVM), Light Gradient Boosting (LGB), Histogram-based Gradient Boosting (HGB), and Extreme Gradient Boosting (XGB)), considering several features selection (Variance Inflation Factor (VIF) and Sequential Feature Selector (SFS)) and hyperparameter tuning (Grid-Search) setup. Results show that the preprocess modeling feature selection (VIF) discards the features that the wrapped method (SFS) keeps, resulting in less reliable crop-type mapping. Additionally, hyperparameter tuning appears to be sensitive to the input features, and considering it after any feature selection improved the crop-type mapping. In this context a three-step nested modeling setup, including first hyperparameter tuning, followed by a wrapped feature selection (SFS) and additional hyperparameter tuning, leads to the most reliable model outputs. For the study region, LGB and XGB (SVM) are the most (least) suitable models for crop-type mapping, and model reliability improves when integrating S1 and S2 features rather than considering S1 or S2 alone. Finally, crop-type maps are derived across different regions and time periods to highlight the benefits of the proposed method for monitoring crop dynamics in space and time. Full article

In meandering river floodplain systems, remote sensing is a valuable tool for assessing connectivity processes relevant to fish ecological functions. This study used the Google Earth Engine platform and multispectral Landsat 7 imagery. A random forest classifier was used to evaluate water types and area changes in oxbow lakes of the Beni River in Bolivia. Water type dynamics were mainly associated with lake age and distance from the main channel. Seasonal variations highlighted the role of wind-driven sediment resuspension and overflow during high discharge conditions. Long-term lake area changes reflected typical oxbow lake evolution as well as alterations caused by the main channel. Multiannual changes showed a notable area decrease during years of low discharge. Relationships between discharge and lake area dynamics allowed the classification of three lake groups with different levels of connectivity and overbank flow influence. The ecological relevance of these groups was evaluated based on fish habitat preferences and migration patterns. Results emphasize the importance of preserving natural hydrologic variability, with flooding associated with increased habitat availability. Overall, this study demonstrates the usefulness of satellite remote sensing for detecting ecohydrological processes and offers insights to preserve ecological functions in data-scarce regions. Full article

The genus Lupinus (Fabaceae) represents an exceptional model system for studying evolutionary processes mediated by pollinators and environmental factors. This review synthesizes evidence on phenotypic variability of floral traits, trait selection by biotic and abiotic factors, and the eco-evolutionary implications of these interactions. Pollinators shape floral traits through specialized selection that optimizes pollination efficiency while maintaining plasticity toward autogamy under pollinator scarcity. At the same time, abiotic pressures drive adaptations to climate and elevation, which Lupinus achieves through phenotypic plasticity, such as adjusting flowering time, and through mutualisms with soil microbes that reduce abiotic stress. Ecological implications reveal contrasting dynamics, where native species sustain specialized pollination networks, while invasive species such as L. polyphyllus Lindl. disrupt these interactions through competitive exclusion. Thus, these two factors collectively drive Lupinus phenotypic diversity through specialized adaptations and plasticity. Finally, we emphasize the need for integrated studies combining genomics and ecological modeling to decipher the adaptive mechanisms of this genus. Full article

The international literature shows significant growth in relation to sustainable rural development in response to ongoing problems. The Principles for Responsible Investment in Agriculture and Food Systems (CFS-RAI) enable projects to be aligned with the Sustainable Development Goals (SDGs). In this article, we present an empirically grounded analysis of these RAI principles based on in-depth case studies in seven countries (Spain, Ecuador, Peru, Dominican Republic, Bolivia, Colombia, and Mexico). This experience comes from an international project coordinated by the GESPLAN Research Group at the Polytechnic University of Madrid. The Working with People model is incorporated into the methodological process to analyze rural actors’ understanding of the CFS-RAI principles in different countries and in university–business relation contexts. The results show the effectiveness of the WWP model based on the integration of three dimensions—ethical–social, technical–business, and political–contextual—as an effective method for planning sustainable rural development projects in various contexts. The empirical evidence presented indicates that combining the WWP model with the principles of CFS-RAI in rural contexts allows progress toward sustainable development, balancing economic aspects with human, social, and environmental well-being. Full article

Brazil nut (Bertholletia excelsa Bonpl.) is a major non-timber forest product in the Amazon, supporting extractivist communities in Brazil, Bolivia, and Peru and contribute to forest conservation. Unlike other extractive products, Brazil nut production has not declined under commercial use and is recognized for its socioeconomic and environmental importance. Precision agriculture has been transformed by the use of unmanned aerial vehicles (UAVs) and artificial intelligence (AI), which enable monitoring efficiency and yield estimation in several crops, including the Brazil nut. This study assessed the potential of using UAV-based imagery combined with YOLOv8 object detection model to identify and quantify Brazil nut fruits in a native forest fragment in eastern Acre, Brazil. A UAV was used to capture canopy images of 20 trees with varying diameters at breast height. Images were manually annotated and used to train the YOLOv8 with an 80/20 split for training and validation/testing. Model performance was evaluated using precision, recall, F1-score, and mean Average Precision (mAP). The model achieved recall above 90%, with an F1-score of 0.88, despite challenges from canopy complexity and partial occlusion. These results indicate that UAV-based imagery combined with AI detection provides an approach for estimating Brazil nut yield, reducing manual effort and improving market strategies for extractivist communities. This technology supports sustainable forest management and socioeconomic development in the Amazon. Full article