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The abandonment of ancestral techniques and the incorporation of new technologies in the production systems for the cultivation of quinoa has resulted in overexploitation of soils, a loss of fertility, water imbalance, a loss of native vegetation cover in plain land areas, and other negative effects on the southern Altiplano agricultural sustainable system. One of the methods to reduce wind erosion and improve soil environmental conditions is establishing a native vegetative barrier. The effect of t’ola [Parastrephia lepidophylla (Wedd.) Cabrera] as a vegetative barrier to prevent wind erosion was evaluated using the rod method, gravimetric humidity fluctuations, and soil quality measurements in traditional quinoa Real production plots. We found significant differences (p < 0.05) for mean erosion, sedimentation, net erosion, and mobilized soil variables. The highest loss of soil was reported for December and November. Vegetative barriers comprising three meters of t’ola better protected bare soils up to 7 m from the barrier, while in bare soils, the loss values were over 5 t ha−1 month−1. Soil humidity fluctuations in plots with t’ola vegetative barriers were highly significant for the distance factors and depth levels. There was a higher accumulation of gravimetric humidity (%) in bare soils from 1.5 m to the barrier (6.95%), while the insides of the vegetative barriers retained an average soil humidity of 6.37%. After two agricultural seasons in the quinoa plots, 62 t ha−1 per year of soils were lost due to a lack of vegetative barriers. Due to the large, cultivated area with quinoa (104,000 ha in 2014) in the Intersalar zone, wind erosion causes 6.48 million tons of soil loss yearly. T’ola vegetative barriers in the southern Altiplano of Bolivia favour the retention of sediments against wind erosion and soil protection for quinoa cultivation. Furthermore, incorporating native lupine increased soil fertility by 80% and protected the soil surface cover.

Vaccine adjuvants play a crucial role in the field of vaccinology, yet they remain one of the least developed and poorly characterized components of modern biomedical research. The limited availability of clinically approved adjuvants highlights the urgent need for new molecules with well-defined mechanisms and improved safety profiles. Hemocyanins, large copper-containing metalloglycoproteins found in mollusks, represent a unique class of natural immunomodulators. Hemocyanins serve as carrier proteins that help generate antibodies against peptides and hapten molecules. They also function as non-specific protein-based adjuvants (PBAs) in both experimental human and veterinary vaccines. Their mannose-rich N-glycans allow for multivalent binding to innate immune receptors, including C-type lectin receptors (e.g., MR, DC-SIGN) and Toll-like receptor 4 (TLR4), thereby activating both MyD88- and TRIF-dependent signaling pathways. Hemocyanins consistently favor Th1-skewed immune responses, which is a key characteristic of their adjuvant potential. Remarkably, their conformational stability supports slow intracellular degradation and facilitates dual routing through MHC-II and MHC-I pathways, thereby enhancing both CD4+ and CD8+ T-cell responses. Several hemocyanins are currently being utilized in biomedical research, including Keyhole limpet hemocyanin (KLH) from Megathura crenulata, along with those from other gastropods such as Concholepas concholepas (CCH), Fissurella latimarginata (FLH), Rapana venosa (RvH), and Helix pomatia (HpH), all of which display strong immunomodulatory properties, making them promising candidates as adjuvants for next-generation vaccines against infectious diseases and therapeutic immunotherapies for cancer. However, their structural complexity has posed challenges for their recombinant production, thus limiting their availability from natural sources. This reliance introduces variability, scalability issues, and challenges related to regulatory compliance. Future research should focus on defining the hemocyanin immunopeptidome and isolating minimal peptides that retain their adjuvant activity. Harnessing advances in structural biology, immunology, and machine learning will be critical in transforming hemocyanins into safe, reproducible, and versatile immunomodulators. This review highlights recent progress in understanding how hemocyanins modulate mammalian immunity through their unique structural features and highlights their potential implications as potent PBAs for vaccine development and other biomedical applications. By addressing the urgent need for novel immunostimulatory platforms, hemocyanins could significantly advance vaccine design and immunotherapy approaches.

This work addresses the task allocation problem in spatial crowdsensing with altruistic participation, tackling challenges like declining engagement and user fatigue from task overload. Unlike typical models relying on financial incentives, this context requires alternative strategies to sustain participation. This paper presents a new solution, the Volunteer Task Allocation Engine (VTAE), to address these challenges. This solution is not based on economic incentives, and it has two primary goals. The first one is to improve user experience by limiting the workload and creating a user-centric task allocation solution. The second goal is to create an equal distribution of tasks over the spatial locations to make the solution robust against the possible decrease in participation. Two approaches are used to test the performance of this solution against different conditions: computer simulations and a real-world experiment with real users, which include a qualitative evaluation. The simulations tested system performance in controlled environments, while the real-world experiment assessed the effectiveness and usability of the VTAE with real users. This research highlights the importance of user-centered design in citizen science applications with altruistic participation. The findings demonstrate that the VTAE algorithm ensures equitable task distribution across geographical areas while actively involving users in the decision-making process.

Immigration has increased significantly in Chile. Despite that all pregnant women, regardless of nationality and immigration status, have the right to access to all healthcare services during pregnancy, childbirth, and postpartum, inequities in health care outcomes and health provision have been reported. During COVID-19 pandemic, these inequities are completely unknown. The aim of this study was to compare the incidence of c-sections according to mother's migration status, as well as other maternal care and perinatal outcomes in women giving birth at San José Hospital in Santiago, Chile, during the COVID-19 pandemic. A retrospective cohort study was designed including 10,166 registered single births at the San José Hospital between March 2020 and August 2021. To compare between groups, statistical tests such as Chi-square and Fisher's exact were used. Log Binomial regression models were performed adjusted for potential confounding variables. To estimate the strength of association the relative risk was used. Immigrant mothers account for 48.1% of the registered births. Compared to non-immigrant women, immigrants exhibit a higher proportion of c-section, specifically, emergency c-section (28.64% vs. 21.10%; -value < 0.001) but a lower proportion of and having a preterm birth (8.24% vs. 13.45%;  < 0.05), receiving personalized childbirth care (13.02% vs. 14.60%; -value < 0.05), companion during labor and childbirth (77.1% vs. 86.95%; -value < 0.001), And postpartum attachment to newborn (73% vs. 79.50%; -value < 0.001). The proportion of COVID exposure was not significant between groups, not the severity also. Haitians had a highest risk of undergoing emergency c-section (aRR = 1.61) and Venezuelans had a highest risk of elective c-section (aRR = 2.18) compared to non-immigrants. This study reports high rates of c-sections in the entire population, but in immigrant populations it is even higher. Additionally, it found gaps in maternal care and perinatal outcomes between immigrants and non-immigrants. More studies are needed to elucidate the possible causes of these differences and establish new regulations to protect the reproductive rights of the immigrant population.

This work investigates and explains the behavior of an acoustic meta-structure based on different coupled Helmholtz resonators (HR). The analytical formulation of the Maa model is used to represent both the acoustic impedance and the sound absorption mechanism of the absorber. The structures are numerically modeled using finite element method and validated experimentally in an impedance tube considering sound waves of normal incidence. The absorber samples were manufactured in ABS (acrylonitrile butadiene styrene) polymer material with the additive manufacturing technique by extrusion of material. The results of the impedance tube, numerical and theoretical tests showed agreement and the sound absorber showed a sub-wavelength scale with perfect sound absorption (  0.97) and broadband of 292 Hz in the low frequency region (200 - 600 Hz). We deduced that the excellent experimental result obtained is due to the high resolution used in the sample manufacturing (± 0.1 mm) which minimized manufacture errors. Finally, the influences of the main parameters of the HR panel (width and depth of the micro-slit) on the sound absorption coefficient of the absorber were also analyzed.

Citizen science now relies heavily on digital platforms to engage the public in environmental data collection. Yet, many projects face declining participation over time. This study examines the effect of three elements of gamification—points, daily streaks, and real-time leaderboards—on student engagement, achievement, and immersion during a five-day campus-wide intervention utilising the GAME and a spatial crowdsourcing app. Employing a convergent mixed-methods design, we combined behavioural log analysis, validated psychometric scales (GAMEFULQUEST), and post-experiment interviews to triangulate both quantitative and qualitative dimensions of engagement. Results reveal that gamified elements enhanced students’ sense of accomplishment and early-stage motivation, which is reflected in significantly higher average scores for goal-directed engagement and recurring qualitative themes related to competence and recognition. However, deeper immersion and sustained “flow” were less robust with repetitive task design. While the intervention achieved only moderate long-term participation rates, it demonstrates that thoughtfully implemented game mechanics can meaningfully enhance engagement without undermining data quality. These findings provide actionable guidance for designing more adaptive, motivating, and inclusive citizen science solutions, underscoring the importance of mixed-methods evaluation in understanding complex engagement processes. While the sample size limits the statistical generalizability, this study serves as an exploratory field trial offering valuable design insights and methodological guidance for future large-scale, controlled citizen science interventions.

La importancia de la investigación en el campo de la teoría de los grupos estratégicos (TGE) se ha incrementado notoriamente en los últimos años, gestándose innumerables trabajos que abordan estos tópicos tanto desde la mirada del pensamiento estratégico, como también, desde la óptica de una herramienta para analizar la competencia de los sectores industriales. Esta teoría parte del supuesto de que la industria es heterogénea y está compuesta por grupos, los cuales a su vez están conformados por entidades que siguen estrategias y tienen recursos similares. El objetivo central de este estudio es analizar los artículos publicados en torno al tema de grupos estratégicos, con el fin de visibilizar la producción científica que se está generando en este campo. Se realiza una búsqueda en revistas especializadas (período 1975-2019) en el Science Citation Index. Se trata de un estudio bibliométrico descriptivo-longitudinal de la producción científica de la TGE, desarrollado sobre la base de un análisis cienciométrico. Dentro de los principales resultados se pueden destacar que los autores más influyentes en grupos estratégicos se encuentran en Estados Unidos, siendo el país que más aporta a la investigación científica en este campo, generando una fuerte y consolidada posición. Por su parte, la revista Strategic Management Journal es la que ha publicado la mayor cantidad de artículos, y la University of Illinois System es la referente en cuanto a este tipo de publicaciones. En relación con las palabras claves utilizadas, se observa un alto nivel de interconexiones, siendo perfomance y strategic groups las más utilizadas.

This dissertation studies three aspects of a class of continuous-time Markov chain models frequently used to describe the stochastic dynamics of a chemical system undergoing a series of reactions which change the numbers of molecules of a finite set of species over time. We call these models Stochastic Chemical Reaction Networks (SCRNs). First, some stochastic ordering results for SCRNs are developed; these are called comparison theorems. These results provide sufficient conditions for establishing monotonic dependence on parameters for SCRNs and associated quantities such as mean first passage times and stationary distributions. Second, some results on singular perturbations for continuous-time Markov chains are developed, motivated by SCRN models for epigenetic cell memory. The focus here is on studying the behavior of the stationary distributions as functions of the singular perturbation parameter. Finally, a reflected diffusion approximation called the Constrained Langevin Approximation (CLA) is studied. Proposed by Leite and Williams, the CLA extends the traditional Langevin approximation beyond the first time some species becomes zero in number. In this dissertation, the approximation of Leite and Williams is extended to (nearly) density dependent Markov chains when the diffusion state space is one-dimensional. In this context, error bounds for the CLA are provided in the form of strong approximations.

PurposeThe Financial Stability Board (FSB) determined that entities classified as shadow banking are of a credit nature because they are capable of affecting the financial system through the entry and exit of capital. This study aims at measuring the impact of shadow banking in the systemic risk in Chile. A sample of 91 institutions (Run) belonging to the mutual funds was used, with a series showing a continuous behaviour between 2004 and 2018.Design/methodology/approachThe measurement is carried out using the conditional value at risk (CoVaR) methodology, which analyses the behaviour of an institution in a regular state against the same institution in a state of stress.FindingsThe results obtained reflect that liquidity mismatches do not have a relevant effect on the systemic risk, while the 2008 crisis does contribute to its decline.Originality/valueThere are less number of literature studies that apply statistical models regarding shadow banking, at least at a quantitative level, so this research is a beginning for other studies, supporting future authors in their new research as a basis.

La importancia de la investigación en el campo de la teoría de los grupos estratégicos (TGE) se ha incrementado notoriamente en los últimos años, gestándose innumerables trabajos que abordan estos tópicos tanto desde la mirada del pensamiento estratégico, como también, desde la óptica de una herramienta para analizar la competencia de los sectores industriales. Esta teoría parte del supuesto de que la industria es heterogénea y está compuesta por grupos, los cuales a su vez están conformados por entidades que siguen estrategias y tienen recursos similares. El objetivo central de este estudio es analizar los artículos publicados en torno al tema de grupos estratégicos, con el fin de visibilizar la producción científica que se está generando en este campo. Se realiza una búsqueda en revistas especializadas (período 1975-2019) en el Science Citation Index. Se trata de un estudio bibliométrico descriptivo-longitudinal de la producción científica de la TGE, desarrollado sobre la base de un análisis cienciométrico. Dentro de los principales resultados se pueden destacar que los autores más influyentes en grupos estratégicos se encuentran en Estados Unidos, siendo el país que más aporta a la investigación científica en este campo, generando una fuerte y consolidada posición. Por su parte, la revista Strategic Management Journal es la que ha publicado la mayor cantidad de artículos, y la University of Illinois System es la referente en cuanto a este tipo de publicaciones. En relación con las palabras claves utilizadas, se observa un alto nivel de interconexiones, siendo perfomance y strategic groups las más utilizadas.