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BACKGROUND: Uptake of mobile phone surveys (MPS) is increasing in many low- and middle-income countries, particularly within the context of data collection on non-communicable diseases (NCDs) behavioural risk factors. One barrier to collecting representative data through MPS is capturing data from older participants.Respondent driven sampling (RDS) consists of chain-referral strategies where existing study subjects recruit follow-up participants purposively based on predefined eligibility criteria. Adapting RDS strategies to MPS efforts could, theoretically, yield higher rates of participation for that age group. OBJECTIVE: To investigate factors that influence the perceived acceptability of a RDS recruitment method for MPS involving people over 45 years of age living in Colombia. METHODS: An MPS recruitment strategy deploying RDS techniques was piloted to increase participation of older populations. We conducted a qualitative study that drew from surveys with open and closed-ended items, semi-structured interviews for feedback, and focus group discussions to explore perceptions of the strategy and barriers to its application amongst MPS participants. RESULTS: The strategys success is affected by factors such as cultural adaptation, institutional credibility and public trust, data protection, and challenges with mobile phone technology. These factors are relevant to individuals willingness to facilitate RDS efforts targeting hard-to-reach people. Recruitment strategies are valuable in part because hard-to-reach populations are often most accessible through their contacts within their social network who can serve as trust liaisons and drive engagement. CONCLUSIONS: These findings may inform future studies where similar interventions are being considered to improve access to mobile phone-based data collection amongst hard-to-reach groups.

Abstract This study offers novel and valuable insights into the spontaneous production of biosurfactant extracts from olive mill waste (OMW) through a steeping process with water at 37 °C for 15 days, followed by extraction with ethyl acetate or phosphate-buffered saline (PBS). The results showed that steeping process significantly improves the extraction efficiency and produces biosurfactant extracts with more favorable critical micellar concentration (CMC) and wettability properties than those from non-steeped OMW. Under best conditions, it yielded 104.6 g/Kg of OMW. Elemental analysis and comparative ATR-FTIR spectroscopy revealed that ethyl acetate biosurfactant extracts is compatible with biosurfactant extracts that contains phospholipids and lipopeptides. It reduced water surface tension to 46.7 mN/m and exhibited a CMC of 0.22 g/L. Conversely, the biosurfactant extract obtained through solid–liquid extraction with PBS was more compatible with glycopeptides biosurfactants, reducing the water surface tension to 50.4 mN/m, similarly to the surface tension values achieved by biosurfactants produced by lactic acid bacteria, but achieving reduced CMC value (0.19 g/L). Therefore, this approach presents a sustainable method for valorizing OMW, promoting sustainability, and circular economy principles. These extracts could have potential applications in various fields, such as soil bioremediation, surface cleaning, and in cosmetic and agrochemical formulations.

Flies belonging to the families Streblidae and Nycteribiidae are highly specialized arthropods that feed on the blood of bats. Their morphology varies and has adapted throughout their coevolutionary history with hosts. Bat flies are often associated with specific bat species and can establish distinct infracommunities. Interaction networks have been used to better understand these associations, revealing interaction modules between bats and their parasites. The Magdalena River basin is the largest in Colombia, encompassing a wide variety of climatic and ecological conditions, with up to 98 bat species reported. We conducted field trips to capture bats and bat flies in different locations along the basin and reviewed literature records and biological collections to gather additional data on interactions between bats and bat flies in this region. We found a high diversity of bats and bat flies in the Magdalena River basin, revealing a medium specialization and modularity in these interactions. We identified bat fly infracommunities and negative associations between certain bat fly species, suggesting competition for resources within hosts. The specialization is similar to that reported in degraded and fragmented habitats where the availability of shelters decreases, favoring the overcrowding of bats, forming multi-species colonies. In conclusion, our study provides important information on the interactions between bats and bat flies in the Magdalena River basin, expanding knowledge about the diversity and structure of these communities in inter-Andean landscapes.

Background/aimsChemical burns to the eye cause extensive ocular surface damage, often resulting in permanent visual impairment. The amniotic membrane (AM), with its regenerative properties, has shown great potential in treating such injuries. Recent innovations, including hydrogel-based delivery systems, have been developed to improve drug retention and promote corneal healing. This study aimed to evaluate whether hydrogels loaded with proteins from human AM could enhance corneal wound healing effectively.MethodsAlkaline burns (8 mm diameter) were induced in the cornea of anesthetized male New Zealand White rabbits (n = 44) by placing filter paper soaked in 1M NaOH on them for 60 s. After rinsed the corneas immediately with a balanced salt solution, the wounds then received: (1) no treatment; (2) AM transplantation; or (3) a dynamic hyaluronic acid hydrogel based on gold thiolate loaded with an AM protein extract (AME); or (4) a physically cross-linked ocular hydrogel insert loaded with the same AME. The contralateral uninjured eye served as a control. The wound area and proportion of healed corneas was assessed in microphotographs. In addition, corneal histology was evaluated by hematoxylin–eosin and Masson’s trichrome staining, examining epithelial and stromal thickness, the endothelial layer, and inflammatory infiltration in the early (day 2) and late (day 28) phases of healing.ResultsThere was more frequent corneal wound closure in animals treated with the hydrogels (treatments 3 and 4) on day 14 (44.4 and 55.5%, respectively) than in the untreated controls (33.3%). Histologically, abnormal re-epithelialization and altered epithelial junctions were observed, with no significant differences in epithelial thickness. Endothelial damage correlated with significant thinning (p = 0.001), with treatments 2 and 3 producing significant differences in the inflammatory infiltrate (p = 0.01).ConclusionApplying new biocompatible hydrogels to the ocular surface that release AM proteins may help close corneal wounds caused by caustic burns. The aggressive nature of burns hinders the detection of differences in the wound area between treatments 28 days after injury. However, improving the adhesion of a solid hydrogel to the mucosa of the ocular surface could enhance these outcomes by keeping the implant in contact with the wound for a longer period.

Abstract Background Measuring collagenase activity is crucial in the field of joint health and disease management. Collagenases, enzymes responsible for collagen degradation, play a vital role in maintaining the balance between collagen synthesis and breakdown in joints. Dysregulation of collagenase activity leads to joint tissue degradation and diseases such as rheumatoid arthritis and osteoarthritis. The development of methods to measure collagenase activity is essential for diagnosis, disease severity assessment, treatment monitoring, and identification of therapeutic targets. Results This study aimed to validate a rapid collagenase activity detection technique using synovial fluid samples. Antibody microarray analysis was initially performed to quantify the levels of matrix metalloproteinase-9 (MMP-9), a major collagenase in joints. Subsequently, the developed gelatin-based test utilizing fluorescence measurement was used to determine collagenase activity. There was a significant correlation between the presence of MMP-9 and collagenase activity. In addition, Lower Limit of Detection and Upper Limit of Detection can be preliminary estimated as 8 ng/mL and 48 ng/mL respectively. Conclusions The developed technique offers a potential point-of-care assessment of collagenase activity, providing real-time information for clinicians and researchers. By accurately quantifying collagenase activity, healthcare professionals can optimize patient care, improve treatment outcomes, and contribute to the understanding and management of joint-related disorders. Further research and validation are necessary to establish the full potential of this rapid collagenase activity detection method in clinical practice.

Pre-season training has been demonstrated to modify the physical fitness and hormone levels in professional soccer players. The present study aimed to analyze the relationships between testosterone and cortisol with anthropometric characteristics in a professional male soccer team after the pre-season period. Fourteen volunteer professional male soccer players participated in this study. Significant decreases in anthropometric characteristics were found. For biochemical measures, cortisol (13) =-5.25, p=.001, d=-.27), testosterone (t (13) =-8.10, p=.001, d=-.65) and C/T ratio (t (13) =-4.07, p=.001, d =-0.2) significantly increased after the pre-season period. Moreover, moderate negative relationships were observed between the percentage of change in body weight, r=0.61, p=.01, body fat percentage, r=.53, p=.04, and testosterone. The present study revealed that the improvements in body composition after intense training in the pre-season period could stimulate anabolic activities such as increases in muscle mass, which is an important result in terms of quality of performance and prevention of injury risk, especially throughout the competitive soccer season. Testosterone and cortisol should be considered for future research as stress and recovery state indicators. In fact, professional soccer staff can use these parameters in combination with other indicators to optimize workloads and avoid overreaching and overtraining. Keywords: Testosterone; cortisol; professional soccer players; performance; physical fitness

Background Uptake of mobile phone surveys (MPS) is increasing in many low- and middle-income countries, particularly within the context of data collection on non-communicable diseases (NCDs) behavioural risk factors. One barrier to collecting representative data through MPS is capturing data from older participants. Respondent driven sampling (RDS) consists of chain-referral strategies where existing study subjects recruit follow-up participants purposively based on predefined eligibility criteria. Adapting RDS strategies to MPS efforts could, theoretically, yield higher rates of participation for that age group. Objective To investigate factors that influence the perceived acceptability of a RDS recruitment method for MPS involving people over 45 years of age living in Colombia. Methods An MPS recruitment strategy deploying RDS techniques was piloted to increase participation of older populations. We conducted a qualitative study that drew from surveys with open and closed-ended items, semi-structured interviews for feedback, and focus group discussions to explore perceptions of the strategy and barriers to its application amongst MPS participants. Results The strategy’s success is affected by factors such as cultural adaptation, institutional credibility and public trust, data protection, and challenges with mobile phone technology. These factors are relevant to individuals’ willingness to facilitate RDS efforts targeting hard-to-reach people. Recruitment strategies are valuable in part because hard-to-reach populations are often most accessible through their contacts within their social network who can serve as trust liaisons and drive engagement. Conclusions These findings may inform future studies where similar interventions are being considered to improve access to mobile phone-based data collection amongst hard-to-reach groups.

Background: The relationship between coronavirus disease 2019 (COVID-19) infection and multiple sclerosis (MS) relapse and disease progression remains unclear. Previous studies are limited by small sample sizes and most lack a propensity-matched control cohort. Objective: To evaluate the effect of COVID-19 infection on MS disease course with a large propensity-matched cohort. Design: This multi-centre cohort study analysed relapse and disability outcomes post-COVID-19 infection after balancing covariates using a propensity score matching method. The study period was from the 11th of September 2019 to the 16th of February 2023. The mean follow-up period was 1.7 years. Methods: Data were retrieved from the MSBase Registry. Propensity scores were obtained based on age, sex, disease duration, baseline Expanded Disability Status Scale (EDSS), MS course, relapses pre-baseline, disease-modifying therapy (DMT) class and country. Primary outcomes were time to first relapse, annualised relapse rate (ARR) and time to confirm EDSS progression. Secondary outcomes were time to EDSS of 3, 4 or 6. Sensitivity analyses with baseline DMT classes were performed. Results: The study included 2253 cases and 6441 controls. After matching, there were 2161 cases and an equal number of matched controls. Cases had a significantly higher ARR (ARR = 0.10 [95% CI 0.09–0.11]) compared to controls (ARR = 0.07 [95% CI 0.06–0.08]). Cases had a significantly greater hazard of time to first relapse compared to controls (hazard ratio (HR) = 1.54 [95% CI 1.29–1.84]). There was no association between COVID-19 infection and 24-week EDSS progression (HR = 1.18 [95% CI 0.92–1.52]), or time to EDSS of 3, 4 or 6. For patients on interferons and glatiramer acetate (BRACE), COVID-19 infection was associated with a greater hazard of time to first relapse (HR = 1.83 [95% CI 1.25–2.68]) and greater hazard of time to EDSS of 3 (HR = 2.04 [95% CI 1.06–3.90]) compared to patients on BRACE therapy without COVID-19 infection. Conclusion: COVID-19 infection was associated with a significantly increased MS relapse rate and a shorter time to first relapse. There was no effect on confirmed EDSS progression over the short term. These results support ongoing COVID-19 risk minimisation strategies to protect patients with MS.

Biosurfactants are molecules with hydrophilic and hydrophobic moieties with the capacity to reduce the surface tension of water. Given the limited quantity of biosurfactant extracts in laboratories, it is recommended to use equipment that requires minimal sample quantities for detecting the presence of biosurfactants. In this work, commercial glycolipids biosurfactants (rhamnolipids or sophorolipids) were diluted in water and subjected to different analyses to obtain their minimum surface tension (ST) reduction and their critical micellar concentration (CMC). The independent variables of the study were: the geometry of platinum plate (rectangular or cylindrical), the sample volume (2, 4 and 20 mL) and the container material consisting of either glass or polytetrafluoroethylene (PTFE). The variation of ST with biosurfactant concentration was studied based on the isotherm model proposed by Li & Lu. It was observed that the profile of ST values did not vary so much using the different independent variables described, observing that platinum rectangular plate can be used for volumes of 4 mL biosurfactants instead of cylindrical plate usually recommended for volumes lower than 20 mL, the container material was also not significant based on the Pearson and Spearman statistical treatment. Moreover, well-fitting regression model results were obtained for a non-commercial biosurfactant extract obtained from a residual stream of the dairy industry, predicting values close to the observed data.

BackgroundSyndromic surveillance for respiratory infections such as COVID-19 is a crucial part of the public health surveillance toolkit as it allows decision makers to detect and prepare for new waves of the disease in advance. However, it is labor-intensive, costly, and increases exposure to survey personnel. This study assesses the feasibility of conducting a mobile phone–based respiratory syndromic surveillance program in a middle-income country during a public health emergency, providing data to support the inclusion of this method in the standard infection control protocols at the population level. ObjectiveThis study aims to assess the feasibility of a national active syndromic surveillance system for COVID-19 disease in Colombia. MethodsIn total, 2 pilots of syndromic mobile phone surveys (MPSs) were deployed using interactive voice response technology in Colombia (367 complete surveys in March 2022 and 451 complete surveys in April and May 2022). Respondents aged 18 years and older were sampled using random digit dialing, and after obtaining consent, they were sent a 10-minute survey with modules on sociodemographic status, respiratory symptoms, past exposure to COVID-19 infection and vaccination status, preferences about COVID-19 vaccination, and information source for COVID-19. Pilot 1 used a nationally representative sample while pilot 2 used quota sampling to yield representative results at the regional level. In this work, we assessed the performance characteristics of the survey pilots and compared the demographic information collected with a nationally representative household survey. ResultsFor both pilots, contact rates were between 1% and 2%, while participation rates were above 80%. The results revealed that younger, female, and higher educated participants were more likely to participate in the syndromic survey. Survey rates as well as demographics, COVID-19 vaccination status, and prevalence of respiratory symptoms are reported for both pilots. We found that respondents of the MPSs are more likely to be younger and female. ConclusionsIn a COVID-19 pandemic setting, using an interactive voice response MPS to conduct syndromic surveillance may be a transformational, low-risk, and feasible method to detect outbreaks. This evaluation expects to provide a path forward to the inclusion of MPSs as a traditional surveillance method.

Cardiotoxicity due to anthracyclines (CDA) affects cancer patients, but we cannot predict who may suffer from this complication. CDA is a complex trait with a polygenic component that is mainly unidentified. We propose that levels of intermediate molecular phenotypes (IMPs) in the myocardium associated with histopathological damage could explain CDA susceptibility, so variants of genes encoding these IMPs could identify patients susceptible to this complication. Thus, a genetically heterogeneous cohort of mice (n = 165) generated by backcrossing were treated with doxorubicin and docetaxel. We quantified heart fibrosis using an Ariol slide scanner and intramyocardial levels of IMPs using multiplex bead arrays and QPCR. We identified quantitative trait loci linked to IMPs (ipQTLs) and cdaQTLs via linkage analysis. In three cancer patient cohorts, CDA was quantified using echocardiography or Cardiac Magnetic Resonance. CDA behaves as a complex trait in the mouse cohort. IMP levels in the myocardium were associated with CDA. ipQTLs integrated into genetic models with cdaQTLs account for more CDA phenotypic variation than that explained by cda-QTLs alone. Allelic forms of genes encoding IMPs associated with CDA in mice, including AKT1, MAPK14, MAPK8, STAT3, CAS3, and TP53, are genetic determinants of CDA in patients. Two genetic risk scores for pediatric patients (n = 71) and women with breast cancer (n = 420) were generated using machine-learning Least Absolute Shrinkage and Selection Operator (LASSO) regression. Thus, IMPs associated with heart damage identify genetic markers of CDA risk, thereby allowing more personalized patient management.

The retina is a highly heterogeneous tissue, both cell-wise but also regarding its extracellular matrix (ECM). The stiffness of the ECM is pivotal in retinal development and maturation and has also been associated with the onset and/or progression of numerous retinal pathologies, such as glaucoma, proliferative vitreoretinopathy (PVR), age-related macular degeneration (AMD), epiretinal membrane (ERM) formation or uveitis. Nonetheless, much remains unknown about the biomechanical milieu of the retina, and specifically the role that Müller glia play as principal mechanosensors and major producers of ECM constituents. So far, new approaches need to be developed to further the knowledge in the field of retinal mechanobiology for ECM-target applications to arise. In this review, we focus on the involvement of Müller glia in shaping and altering the retinal ECM under both physiological and pathological conditions and look into various biomaterial options to more accurately replicate the impact of matrix stiffness in vitro.

Currently, Gramicidin S (GR-S) is produced enzymatically with the drawback of the presence of trifluoroacetic acid (TFA) or produced by fermentation involving several separation and purification steps. Therefore, this study is focused on the use of green solvents as unique extraction step to produce Gramicidin S from microbial biomass of Aneurinibacillus aneurinilyticus. Among the tested solvents, such as ethanol, acidic ethanol or buffer phosphate, the most favorable was acidic ethanol, extracting 96% of Gramicidin S from cells with a purity of 90%. Using acidic ethanol, extraction time within the range of 30–120 min exhibited minimal impact on Gramicidin S yield, whereas the biomass-to-extractant ratio emerged as a critical parameter. Gramicidin S extracts were characterized using Fourier Transform Infrared Spectroscopy (FTIR), Matrix Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF-MS), and Electrospray Ionization Mass Spectrometry (ESI-MS) coupled with Ultra Performance Liquid Chromatography (UPLC) and compared with commercial Gramicidin S.

El trabajo busca determinar si la crisis, diagnosticada por Husserl, es un obstáculo para la felicidad. A través de esto, explicitamos conexiones entre ética y generatividad poco investigadas por la literatura especializada. Comenzamos exponiendo la teoría de la felicidad de Husserl, con el fin de utilizarla como marco teórico para el argumento posterior. Proseguimos exponiendo el concepto de crisis en Husserl como uno de carácter generativo, mostrando cómo ésta tiene consecuencias prácticas que merman la posibilidad de los individuos de alcanzar la autonomía y la felicidad. Finalizamos exponiendo el modo en que Husserl ha concebido que la fenomenología participa en la resolución de la crisis.

El presente trabajo explora el abordaje fenomenológico de la diferencia sexual en la interpretación que realiza Sara Heinämaa (2003) de la obra de Simone de Beauvoir, cuya tesis principal consiste en comprender la diferencia sexual como una diferencia de estilo, una noción de la fenomenología husserliana retomada por Merleau-Ponty, que en este contexto refiere a un modo compartido de relacionarse con las cosas y el mundo. A pesar de la riqueza de este enfoque, ciertos aspectos relativos al origen y la reproducción de ese estilo no son explícitamente explorados. Esto puede subsanarse, por un lado, atendiendo a la diferencia entre estilos y tipos; y por otro, recuperando la estrecha vinculación del estilo con la institución en la obra de Merleau-Ponty. Esto implica acercar nuestra comprensión del género a una teoría de la performatividad, entendiendo el género como estilo instituido.

Abstract Background Glaucoma, a progressive neurodegenerative disease, is a leading cause of irreversible vision loss worldwide. This study aims to elucidate the critical role of Müller glia (MG) in the context of retinal ganglion cell (RGC) death, particularly focusing on the influence of peripheral MG sensitivity to high pressure (HP). Methods Co-cultures of porcine RGCs with MG were isolated from both the central and peripheral regions of pig retinas and subjected to both normal and HP conditions. Mass spectrometry analysis of the MG-conditioned medium was conducted to identify the proteins released by MG under all conditions. Results Peripheral MG were found to secrete a higher quantity of neuroprotective factors, effectively promoting RGC survival under normal physiological conditions. However, under HP conditions, co-cultures with peripheral MG exhibited impaired RGC survival. Moreover, under HP conditions, peripheral MG significantly upregulated the secretion of proteins associated with apoptosis, oxidative stress, and inflammation. Conclusions This study provides robust evidence suggesting the involvement of MG in RGC death in glaucoma, thus paving the way for future therapeutic investigations.

Understanding the external load, particularly the peak demands (PDs), experienced by players is essential. Several factors, such as the playing time, team venue, score outcome, and match nature, can influence basketball performance. Accelerometry-based methods allow for the estimation of the load borne by athletes and the peaks they reach. The aim of this study was to analyze the influence of these factors on PDs across different time windows (30 s, 1 min, and 3 min). Eleven national-level athletes were monitored during 29 matches using measurement devices. Inertial movement units were used to measure peak PlayerLoad™ (PL) across any time window. Mixed linear models were used to compare the groups, and effect size was calculated to quantify the differences. Significant differences (p < 0.05, small effects) were found between occasional players (who play fewer minutes) and core players (who play intermediate minutes), with the latter reaching higher PDs, though with small effect sizes. Core players also reached higher PDs than top players (who play the most minutes), but the differences were not significant (p > 0.05, trivial effects). In summary, core players reach higher external PDs during competition compared to occasional players, while other contextual factors did not show a significant influence on external PDs.

Background/Objective: This study investigated the differences in acute fatigue following resistance training performed with low versus high loads in the bench press (BP). Methods: Trained males (n = 5, 21.2 ± 2.77 years; 81.86 ± 6.67 kg; 177 ± 7.52 cm) undertook three protocols with 50%RM and three with 85%RM with volume equalized between protocols: muscular failure protocols (TF, RTP1 and 2), half-maximum repetition protocols (RTP3 and 4), and cluster set protocols (RTP5 and 6). Mechanical performance, lactate, and perceptual responses were analyzed during protocols and at post 0, 24, and 48 h using frequentist (p < 0.05) and Bayesian approaches. Results: Moderate to large (ES ≥ 0.3) and trivial to moderate (ES < 0.3) effects were observed at 0 and 24 h post-session, respectively, across all protocols. TF protocols, particularly RTP1, showed the greatest impairments when compared to the other RTP (ES ≥ 0.3). The Bayesian analysis supported the frequentist results, showing strong-decisive evidence for our data under the model that included protocols as predictors for mechanical, metabolic, and perceptual variables during protocols. Inter-individual variability in responses was observed in the neuromuscular tests, potentially related to the strength level and perceptual responses. Conclusions: In summary, TF generates greater fatigue, while reducing set volume to half of maximum repetitions or including intra-set rest that helps to mitigate fatigue symptoms.

Metabolic changes that facilitate tumor growth are one of the hallmarks of cancer. These changes are not specific to tumors but also take place during the physiological growth of tissues. Indeed, the cellular and tissue mechanisms present in the tumor have their physiological counterpart in the repair of tissue lesions and wound healing. These molecular mechanisms have been acquired during metazoan evolution, first to eliminate the infection of the tissue injury, then to enter an effective regenerative phase. Cancer itself could be considered a phenomenon of antagonistic pleiotropy of the genes involved in effective tissue repair. Cancer and tissue repair are complex traits that share many intermediate phenotypes at the molecular, cellular, and tissue levels, and all of these are integrated within a Systems Biology structure. Complex traits are influenced by a multitude of common genes, each with a weak effect. This polygenic component of complex traits is mainly unknown and so makes up part of the missing heritability. Here, we try to integrate these different perspectives from the point of view of the metabolic changes observed in cancer.

Metabolic changes that facilitate tumor growth are one of the hallmarks of cancer. The triggers of these metabolic changes are located in the tumor parenchymal cells, where oncogenic mutations induce an imperative need to proliferate and cause tumor initiation and progression. Cancer cells undergo significant metabolic reorganization during disease progression that is tailored to their energy demands and fluctuating environmental conditions. Oxidative stress plays an essential role as a trigger under such conditions. These metabolic changes are the consequence of the interaction between tumor cells and stromal myofibroblasts. The metabolic changes in tumor cells include protein anabolism and the synthesis of cell membranes and nucleic acids, which all facilitate cell proliferation. They are linked to catabolism and autophagy in stromal myofibroblasts, causing the release of nutrients for the cells of the tumor parenchyma. Metabolic changes lead to an interstitium deficient in nutrients, such as glucose and amino acids, and acidification by lactic acid. Together with hypoxia, they produce functional changes in other cells of the tumor stroma, such as many immune subpopulations and endothelial cells, which lead to tumor growth. Thus, immune cells favor tissue growth through changes in immunosuppression. This review considers some of the metabolic changes described in breast cancer.

Abstract Although the characterization of the sticking and aggregation probability is essential to the description of volcanic ash dispersal and sedimentation, there is still no general model describing the sticking probability of volcanic ash. Experiments of dry particle–plate collisions in an enclosed box were carried out to characterize quantitatively the sticking efficiency of volcanic particles and silica beads in a limit case scenario where the mass of one of the particles is much greater than the others. Silica beads and volcanic particles from a Sakurajima Vulcanian eruption were filmed impacting a glass plate with a High-Speed Camera. The sticking probability is calculated from an equation depending on the particle diameter, impact velocity, and two experimental parameters (a, q). Particle size was found to dominantly control the sticking probability, with small particles more likely sticking on the glass plate than large particles. These experiments represent a significant step forward in the quantification of the sticking efficiency of fine volcanic ash (

Business survival has been a widely studied phenomenon in management literature given its impact on economic and social reality. There is some consensus that crises have a catalytic effect by driving the least efficient, productive, and profitable firms out of the market, while those best prepared with better technology, products, or business structure survive; this process is known as creative destruction. This study analyzed a sample of 5,000 firms using statistical survival models in order to identify the main factors affecting the life and disappearance of firms in periods of crisis (2008–2012) versus periods of recovery (2016–2020) to detect differentiated patterns of behavior. It was found that those firms that were driven out of the market during the crisis, unlike in the subsequent recovery period, were neither the less profitable nor the less efficient. Instead, more indebted firms or those that did not get the support of credit institutions were withdrawn from market. This result casts doubt on the effectiveness of the theorized process of creative destruction in times of economic crisis.

La industria curtidora necesita implementar cambios y adoptar tecnologías innovadoras para garantizar una gestión eficiente, enfocada en la sostenibilidad ambiental, social y económica. El trabajo se desarrolló en el año 2022, con el fin de proponer mejoras al proyecto "Arte del Cuero" en la Isla de la Juventud, especialmente para tratar las pieles de ganado vacuno generadas en la Unidad Empresarial de Base Cárnico "Abel Santamaría Cuadrado". La recopilación de datos se realizó a través de diversas fuentes, incluyendo el área de tecnología de producción, entrevistas a los productores de la minindustria y a la Unidad Empresarial de Base Cárnico "Abel Santamaría", así como mediante observaciones directas de los procesos tecnológicos. Entre los problemas identificados se encuentran: dificultades en procesamiento, equipamiento obsoleto, capacidad insuficiente, transporte limitado y falta de estudio económico. Entre los resultados destacados, se enfatiza la necesidad de coordinar con las unidades productivas pecuarias para el cuidado en el marcaje de las pieles de los animales, lo que garantiza así la utilización óptima de todos los cueros disponibles. El cumplimiento del objetivo no solo arrojó resultados concretos, sino que también se implicó en la promoción del procesamiento de pieles mediante una minindustria de tenería, con la colaboración de actores locales para fortalecer el proyecto. Se propusieron acciones específicas que no solo mejoraron la eficiencia y sostenibilidad del proceso productivo, sino que también garantizaron la disponibilidad de materia prima a nivel local para consolidar así el proyecto como un referente para el aprovechamiento de las pieles generadas por la industria cárnica.

Un agente parasitario no identificado fue analizado en un lote de Pterophyllum scalare adquiridos por el Laboratorio de Ictiología y Peces Ornamentales de la Universidad Nacional de Colombia, sede Bogotá. El lote de animales tenía como antecedente haber cursado su etapa de levante en estanques de tierra. Con el pasar de los días, durante el periodo de cuarentena en acuario, una fracción del lote, correspondiente a la variedad Koi, empezó a presentar estructuras anormales color blanco en las aletas; estructuras que tuvieron una lenta diseminación hacia la zona de la corona. Para determinar el agente causal de este fenómeno, se analizó una muestra de aleta, identificando la presencia de metacercarias del parásito Clinostomum sp. Con dicha información se procedió a realizar un tratamiento antiparasitario empleando un fármaco destinado a pequeñas especies a base de Praziquantel y Pamoato de Pirantel (Vermiplex® de Laboratorios ZOO). El fármaco fue administrado vía oral con una dosis de 25 mg totales de Praziquantel y 75 mg totales en el agua; logrando una recuperación total de los animales afectados al desaparecer completamente las estructuras parasitarias y no presentar reincidencia luego de un periodo de 20 días desde el inicio del tratamiento.