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Abstract Introduction: Evidence suggests that herbivores, such as peccaries, shape vegetation structure and diversity through predation, trampling, dispersal, and rooting behavior. Objective: To evaluate the impact of peccaries (Dycotiles tajacu) on the understory vegetation of the tropical rainforest in the Nogal-La Selva Local Biological Corridor, Costa Rica, comparing a site with the absence of peccaries to another with the presence of these animals. Methodology: From June to November 2021, 20 experimental exclusions and 20 free access plots, each measuring 2 m2 were used to quantify herbivory, the number of leaf blades, damaged leaves, healthy leaves, sapling height, and fallen biomass at both sites. Results: A higher sapling density was found in the Nogal Reserve, but a lower sapling diversity, while in La Selva there was a higher sapling diversity, but a lower density of seedlings. Herbivory and sapling height in La Selva exceeded those in Nogal. The exclusion of peccaries reduced seedling damage but did not affect the dynamics of fallen biomass. Conclusion: For the design, implementation, and evaluation of the effectiveness of biological corridors, it is crucial to consider plant-animal interactions to enhance the flow of ecological processes through functional and structural connectivity, analyzed from interactions such as those presented in this paper.

Resumen Introducción: Existe evidencia que herbívoros, como los saínos, dan forma a la estructura y diversidad de la vegetación a través del comportamiento de depredación, pisoteo, dispersión y enraizamiento. Objetivo: Evaluar el impacto de los saínos (Dycotiles tajacu) en la vegetación del sotobosque del bosque tropical húmedo en el Corredor Biológico Local Nogal-La Selva, Costa Rica, en un sitio con ausencia y en otro con presencia de saínos. Métodos: De junio a noviembre de 2021 se utilizaron 20 exclusiones experimentales y 20 parcelas de acceso libre de 2 m2, se cuantifico la herbivoría, número de láminas foliares, hojas dañadas, hojas sanas, altura de brinzales y biomasa caída en ambos sitios. Resultados: Se encontró una mayor densidad de brinzales en Reserva Nogal pero una menor diversidad, contrario en La Selva donde se encontró una mayor diversidad de brinzales, pero una menor densidad de plántulas. La herbivoría y la altura de brinzales en La Selva fue mayor que en Nogal. La exclusión de los saínos disminuyó el daño a las plántulas, pero no afectó la dinámica de la biomasa caída. Conclusión: Es necesario contemplar para el diseño, implementación y evaluación de la efectividad de corredores biológicos, las interacciones planta-animal, para potencializar el flujo de procesos ecológicos mediante la conectividad funcional y estructural, analizada a partir de interacciones como las presentadas en este trabajo.

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Vulnerability curves (VCs) have been measured extensively to describe the differences in plant vulnerability to cavitation. Although the roles of hydraulic conductivity (Ks,max) and hydraulic safety (P50, embolism resistance), both of which are parameters of VCs ('sigmoidal' type), in tree demography have been evaluated across different forests, the direct linkages between VCs and tree demography are rarely explored. In this study, we combined measured VCs and plot data of 16 tree species in Panamanian seasonal tropical forests to investigate the connections between VCs and tree mortality, recruitment and growth. We found that the mortality and recruitment rates of evergreen species were most significantly positively correlated with P50. However, the mortality and recruitment rates of deciduous species only exhibited significant positive correlations with parameter a, which describes the steepness of VCs and indicates the sensitivity of conductivity loss with water potential decline, but is often neglected. These differences among evergreen and deciduous species may contribute to the poor performance of existing quantitative relationships (such as the fitting relationships for all 16 species) in capturing tree mortality and recruitment dynamics. Additionally, evergreen species presented a significant positive relationship between relative growth rate (RGR) and Ks,max, while deciduous species did not display such relationship. The RGR of both evergreen and deciduous species also displayed no significant correlations with P50 and a. Further analysis demonstrated that species with steeper VCs tended to have high mortality and recruitment rates, while species with flatter VCs were usually those with low mortality and recruitment rates. Our results highlight the important role of parameter a in tree demography, especially for deciduous species. Given that VC is a key component of plant hydraulic models, integrating measured VC rather than optimizing its parameters will help improve the ability to simulate and predict forest response to water availability.

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Secondary tropical forests play an increasingly important role in carbon budgets and biodiversity conservation. Understanding successional trajectories is therefore imperative for guiding forest restoration and climate change mitigation efforts. Forest succession is driven by the demographic strategies-combinations of growth, mortality and recruitment rates-of the tree species in the community. However, our understanding of demographic diversity in tropical tree species stems almost exclusively from old-growth forests. Here, we assembled demographic information from repeated forest inventories along chronosequences in two wet (Costa Rica, Panama) and two dry (Mexico) Neotropical forests to assess whether the ranges of demographic strategies present in a community shift across succession. We calculated demographic rates for >500 tree species while controlling for canopy status to compare demographic diversity (i.e., the ranges of demographic strategies) in early successional (0-30 years), late successional (30-120 years) and old-growth forests using two-dimensional hypervolumes of pairs of demographic rates. Ranges of demographic strategies largely overlapped across successional stages, and early successional stages already covered the full spectrum of demographic strategies found in old-growth forests. An exception was a group of species characterized by exceptionally high mortality rates that was confined to early successional stages in the two wet forests. The range of demographic strategies did not expand with succession. Our results suggest that studies of long-term forest monitoring plots in old-growth forests, from which most of our current understanding of demographic strategies of tropical tree species is derived, are surprisingly representative of demographic diversity in general, but do not replace the need for further studies in secondary forests.

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In 2007, Mexico implemented a strategy to combat drug trafficking through military intervention, after which a significant increase in homicides, mainly among young men, was observed and linked to structural problems as well as organized crime, especially the recruitment of youth, with adolescents being particularly vulnerable. Through a systematic review of the literature from 2013 to 2022, we have compiled the reported factors influencing the recruitment of adolescents by organized crime in Mexico and conducted a metasynthesis of the data according to the multiple levels that affect adolescents: individual, family, community, cultural, and social. This research has shown that many of the factors reported are interrelated and need to be studied holistically. In addition, many of the factors are common to other forms of juvenile delinquency, but the main difference is the presence of organized crime itself in the community and culture.

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BACKGROUND: Human records describe pulmonary edema as a life-threatening complication of electric shock. Successful management requires prompt recognition and intensive care. However, in companion animals, electrocutions are rarely reported, even though domestic environments are full of electrical devices and there is always the possibility of accidental injury. Therefore, it is important for veterinarians to know more about this condition in order to achieve successful patient outcomes. CASE PRESENTATION: A 3-month-old male Labrador Retriever was presented with a history of transient loss of consciousness after chewing on a household electrical cord. On admission, the puppy showed an orthopneic position with moderate respiratory distress. Supplemental oxygen via nasal catheter was provided, but the patient showed marked worsening of respiratory status. Point-of-care ultrasound exams suggested neurogenic pulmonary edema due to electrical shock close to the central nervous system and increased B-lines without evidence of cardiac abnormalities. Mechanical ventilation of the patient was initiated using volume-controlled mode with a tidal volume of 9 to 15 ml/kg until reaching an end-tidal carbon dioxide ≤ 40 mm Hg, followed by a stepwise lung-recruitment maneuver in pressure-controlled mode with increases of the peak inspiratory pressure (15 to 20 cm H2O) and positive end-expiratory pressure (3 to 10 cm H2O) for 30 min, and return to volume-controlled mode with a tidal volume of 15 ml/kg until reaching a peripheral oxygen saturation ≥ 96%. Weaning from the ventilator was achieved in six hours, and the patient was discharged two days after admission without neurological or respiratory deficits. CONCLUSIONS: We present a rather unusual case of a neurogenic pulmonary edema subsequent to accidental electrocution in a dog. Timely diagnosis by ultrasound and mechanical ventilation settings are described. Our case highlights that pulmonary edema should be considered a potentially life-threatening complication of electrical shock in small animal emergency and critical care medicine.

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La atrofia muscular espinal (AME) de presentación temprana representa la variante más severa, con una expectativa de vida generalmente no mayor a dos años sin soporte ventilatorio, debido a la insuficiencia respiratoria y la dificultad para toser. Tradicionalmente, el manejo respiratorio en muchos países ha incluido la traqueostomía para proporcionar asistencia ventilatoria invasiva de manera continua. No obstante, la introducción de medicamentos de precisión ha modificado la progresión natural de la enfermedad, evidenciando mejoras significativas en los hitos motores y beneficiando también la función respiratoria. A pesar de estas mejoras, en muchos casos sigue siendo necesaria la ventilación intermitente y/o continua, además de la facilitación de la tos. Estas necesidades pueden abordarse de forma no invasiva mediante el soporte ventilatorio no invasivo (SVN), la in-exsuflación mecánica (IEM) y el reclutamiento de volumen pulmonar (RVP), que son considerados pilares del tratamiento respiratorio en enfermedades neuromusculares. Estas estrategias promueven el desarrollo y mantenimiento de la función respiratoria, reduciendo el riesgo de exacerbaciones respiratorias que podrían llevar a intubaciones evitables. Comúnmente, los pacientes con AME experimentan intentos fallidos de extubación siguiendo protocolos tradicionales, siendo catalogados como no extubables y potenciales candidatos a traqueostomía. No obstante, existen protocolos de extubación específicos para AME que emplean SVN e IEM con un alto porcentaje de éxito, evitando traqueostomías innecesarias que pueden complicar la progresión de la enfermedad y afectar la calidad de vida. El enfoque respiratorio no invasivo es una opción de manejo segura tanto en el hospital como en el hogar, ofreciendo una mejor calidad de vida para los pacientes y sus familias.

Early-onset spinal muscular atrophy (SMA) is the most severe variant, with a life expectancy generally not exceeding two years without ventilatory support due to respiratory insufficiency and difficulty in coughing. Traditionally, respiratory management in many countries has included tracheostomy to provide continuous invasive ventilatory support. However, the introduction of precision medicine has altered the natural progression of the disease, showing significant improvements in motor milestones and also benefiting respiratory function. Despite these improvements, many cases still require intermittent and/or continuous ventilation, as well as cough facilitation. These needs can be addressed non-invasively through non-invasive ventilatory support (NIV), mechanical insufflation-exsufflation (MIE), and lung volume recruitment (LVR), which are considered the pillars of respiratory treatment in neuromuscular diseases. These strategies promote the development and maintenance of respiratory function, reducing the risk of respiratory exacerbations that could lead to avoidable intubations. Commonly, SMA patients experience failed extubation attempts following traditional protocols, being labeled as non-extubatable and potential candidates for tracheostomy. Nevertheless, there are specific extubation protocols for SMA that employ NIV and MIE with a high success rate, avoiding unnecessary tracheostomies that can complicate disease progression and impact quality of life. The non-invasive respiratory approach is a safe management option both in the hospital and at home, offering a better quality of life for patients and their families.

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CONTEXT: The aim of this study was to analyze the muscle activity of the hamstring muscles and the lateral gastrocnemius during different variants of the single-leg bridge (SLB) in futsal players. DESIGN: Cross-sectional study. METHODS: Twenty-two futsal players (age = 24.8 [3.9] y) volunteered to participate in this study. The participants performed 3 variations of the SLB with the knee flexed at 45°. The first position was performed with the ankle in plantar position with flat support, the second with the ankle in dorsiflexion (DF) with heel support, and the third with the ankle in DF and external rotation (ER) with heel support. The Wilcoxon rank-sum test assessed the difference between variables for samples with the rank-biserial correlation effect size. Spearman correlation coefficients were used to examine the associations of the percentage maximal voluntary isometric contraction for each muscle with peak force and rate of force development with 3 different variances of the SLB. RESULTS: The variation of ankle DF and ER with heel support generated higher muscle activity in BF in concentric (P < .01, effect size [ES] = -0.613); isometric (P < .042, ES = -0.494); and eccentric (P < .005, ES = -0.668) contraction than ankle DF with heel support. In contrast, the variation of ankle DF and ER with heel support generated fewer muscle activity in lateral gastrocnemius in concentric (P < .001, ES = 0.779); isometric (P < .003, ES = 0.708); and eccentric (P < .014, ES = 0.589) contraction than ankle DF with heel support. CONCLUSIONS: The position of DF and ER was the best position in SLB to train the BF. It could be convenient to start rehabilitation of the BF with flat foot postition or ankle in DF with heel support and progress with the position of the ankle in DF and ER with heel support.

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Introduction: Multiple sclerosis (MS) is a chronic autoimmune disease of the central nervous system characterized by neuroinflammation leading to demyelination. The associated symptoms lead to a devastating decrease in quality of life. The cannabinoids and their derivatives have emerged as an encouraging alternative due to their management of symptom in MS. Objective: The aim of the study was to investigate the mechanism of action of cannabidiol (CBD), a nonpsychoactive cannabinoid, on molecular and cellular events associated with leukocyte recruitment induced by experimental autoimmune encephalomyelitis (EAE). Materials and Methods: C57BL/6 female mice were randomly assigned to the four experimental groups: C (control group), CBD (cannabidiol-treated group, 5 mg/kg i.p.; 14 days), EAE (experimental autoimmune encephalomyelitis-induced group), and EAE+CBD (experimental autoimmune encephalomyelitis-induced plus cannabidiol-treated group). Results: The results indicated that 5 mg/kg of CBD injected intraperitoneally between the 1st and 14th days of EAE could reduce the leukocyte rolling and adhesion into the spinal cord microvasculature as well cellular tissue infiltration. These results were supported by a decreased mRNA expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) in the spinal cord. Conclusion: Purified CBD reduces in vivo VCAM and ICAM-mediated leukocyte recruitment to the spinal cord microvasculature at EAE peak disease.

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Online surveys are routinely used in mental health screening and treatment follow-up assessment, though they can yield low response rates. We tested the effects of social psychology-informed influence strategies for increasing rates of participation in an online mental health screening survey (Experiment 1) and a treatment follow-up survey (Experiment 2). In Experiment 1 (N = 45,569), embedding one or any combination of three motivational appeals (personal gain, community gain, and inclusivity) in screening survey invitation and reminder emails unexpectedly led to lower rates of survey participation compared to when the appeals were not included (overall participation rate = 12.02%, ORs = 0.75 to 0.97, ps < .001). In Experiment 2 (N = 873), a video of a TikTok influencer encouraging survey participation embedded in treatment follow-up survey invitation and reminder emails did not significantly affect survey completion compared to a humorous gif unrelated to survey participation (overall participation rate = 47.88%, OR = 1.18, p = .200). Moderator analyses revealed that the video led to higher rates of participation than the gif among White participants (OR = 1.39, p = .031) and non-Hispanic participants (OR = 1.35, p = .029) only, whereas the video led to lower rates of participation than the gif among students who did not disclose their race (OR = 0.31, p = .010). Results suggested that efforts to improve online survey participation should be balanced with possible downsides (e.g., added email length) and should be evaluated for differential performance among population subgroups prior to widespread implementation.