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In the pursuit of new lead compounds with fewer side effects than opioids, the novel synthetic phytochemical core, 3,3-dibromoflavanone (3,3-DBF), has emerged as a promising candidate for pain management. Acute assays demonstrated dose-dependent central and peripheral antinociceptive activity of 3,3-DBF through the µ-opioid receptor. This study aimed to explore repeated administration effects of 3,3-DBF in mice and compare them with morphine. Mice were treated with 3,3-DBF (30 mg/kg), morphine (6 mg/kg), or vehicle for 10 days, alongside single-treatment groups. Unlike morphine, 3,3-DBF demonstrated antinociceptive effects in the hot plate test without inducing tolerance. Locomotor activity and motor coordination tests (evaluated through the inverted screen and rotarod tests) revealed no significant differences between the 3,3-DBF-treated and control groups. The gastrointestinal transit assay indicated that 3,3-DBF did not induce constipation, in contrast to morphine. Furthermore, withdrawal signs assessed with the Gellert-Holtzman scale were not comparable to morphine. Additionally, 3,3-DBF exhibited antidepressant-like activity, reducing immobility time in the forced swimming and tail suspension tests, akin to imipramine. In summary, 3,3-DBF demonstrated antinociceptive effects without inducing tolerance or dependence and exhibited antidepressant properties. These findings highlight the potential of 3,3-DBF as a promising therapeutic agent for pain management and its comorbidities, offering advantages over morphine by minimizing side effects.

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Despite prenol emerging as a next-generation biofuel, some questions about its mechanism still need to be adequately proposed to rationalize its consumption and evaluate its efficiency in spark-ignition (SI) engines. Here, we present new insights into the reaction mechanism of prenol (3-methyl-2-buten-1-ol) with OH radicals as a function of temperature and pressure. We have determined that the different temperature and pressure conditions control the preferred products. At combustion temperatures and low pressures, OH-addition adducts are suppressed, increasing the formation of α and δ allylic radicals responsible for the auto-ignition.

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Lianas are major contributors to tropical forest dynamics, yet we know little about their mortality. Using overlapping censuses of the lianas and trees across a 50 ha stand of moist tropical forest, we contrasted community-wide patterns of liana mortality with relatively well-studied patterns of tree mortality to quantify patterns of liana death and identify contributing factors. Liana mortality rates were 172% higher than tree mortality rates, but species-level mortality rates of lianas were similar to trees with 'fast' life-history strategies and both growth forms exhibited similar spatial and size-dependent patterns. The mortality rates of liana saplings (<2.1 cm in diameter), which represent about 50% of liana individuals, decreased with increasing disturbance severity and remained consistently low during post-disturbance stand thinning. In contrast, larger liana individuals and trees of all sizes had elevated mortality rates in response to disturbance and their mortality rates decreased over time since disturbance. Within undisturbed forest patches, liana mortality rates increased with increasing soil fertility in a manner similar to trees. The distinct responses of liana saplings to disturbance appeared to distinguish liana mortality from that of trees, whereas similarities in their patterns of death suggest that there are common drivers of woody plant mortality.

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Negative density dependence (NDD) in biotic interactions of interference such as plant-plant competition, granivory and herbivory are well-documented mechanisms that promote species' coexistence in diverse plant communities worldwide. Here, we investigated the generality of a novel type of NDD mechanism that operates through the mutualistic interactions of frugivory and seed dispersal among fruit-eating birds and plants. By sampling community-wide frugivory interactions at high spatial and temporal resolution in Pennsylvania, Puerto Rico, Peru, Brazil and Argentina, we evaluated whether interaction frequencies between birds and fruit resources occurred more often (selection), as expected, or below expectations (under-utilization) set by the relative fruit abundance of the fruit resources of each plant species. Our models considered the influence of temporal scales of fruit availability and bird phylogeny and diets, revealing that NDD characterizes frugivory across communities. Irrespective of taxa or dietary guild, birds tended to select fruits of plant species that were proportionally rare in their communities, or that became rare following phenological fluctuations, while they mostly under-utilized abundant fruit resources. Our results demonstrate that negative density-dependence in frugivore-plant interactions provides a strong equalizing mechanism for the dispersal processes of fleshy-fruited plant species in temperate and tropical communities, likely contributing to building and sustaining plant diversity. This article is part of the theme issue 'Diversitydependence of dispersal: interspecific interactions determine spatial dynamics'.

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Dementia is a syndrome characterized by cognitive and neuropsychiatric symptoms associated with progressive functional decline (FD). FD is a core diagnostic criterion for dementia, setting the threshold between its prodromal stages and the full-blown disease. The operationalization of FD continues to generate a great deal of controversy. For instance, the threshold of FD for the diagnosis of dementia varies across diagnostic criteria, supporting the need for standardization of this construct. Moreover, there is a need to reconsider how we are measuring FD to set boundaries between normal aging, mild cognitive impairment, and dementia. In this paper, we propose a multidimensional framework that addresses outstanding issues in the assessment of FD: i) What activities of daily living (ADLs) are necessary to sustain an independent living in aging? ii) How to assess FD in individuals with suspected neurocognitive disorders? iii) To whom is the assessment directed? and iv) How much does FD differentiate healthy aging from mild and major neurocognitive disorders? Importantly, the To Whom Question introduces a person-centered approach that regards patients and caregivers as active agents in the assessment process of FD. Thus, once impaired ADLs have been identified, patients can indicate how significant such impairments are for them in daily life. We envisage that this new framework will guide future strategies to enhance functional assessment and treatment of patients with dementia and their caregivers.

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The aim of the present study was to evaluate and compare exercise addiction (EA) between runners, cyclists, swimmers, and triathletes. Took part in this study 39 runners, 32 cyclists, 30 swimmers and 38 triathletes. Exercise Dependence Scale (EDS), and the Exercise Addiction Inventory (EAI) was used to evaluate the EA and classified the participants into: at-risk for EA, nondependent-symptomatic, and nondependent-asymptomatic. Most participants were classified as nondependent symptomatic for EA. The EDS total score was significantly lower in the swimmers compared to the cyclists and triathletes and the EAI total score was significantly higher for cyclists compared to runners. Therefore, in both instruments, the majority of participants was nondependent symptomatic for EA (AU).

O objetivo do presente estudo foi avaliar e comparar a dependência ao exercício (DE) entre corredores, ciclistas, nadadores e triatletas. Participaram do estudo 39 corredores, 32 ciclistas, 30 nadadores e 38 triatletas. As escalas Exercise Dependence Scale (EDS) e Exercise Addiction Inventory (EAI) foram usadas para a avaliação da DE e classificaram os participantes em três categorias: em risco de DE, não dependente sintomático e não dependente assintomático. A maioria dos participantes foram classificadas como não dependentes sintomáticos para DE. O escore da EDS foi significativamente menor nos nadadores comparado aos ciclistas e triatletas e o escore total da EAI foi significantemente maior nos ciclistas comparado aos corredores. Portanto, em ambos os instrumentos, a maioria dos participantes foi não dependente sintomático para DE (AU).

El objetivo del presente estudio fue evaluar y comparar la adicción al ejercicio (AE) entre corredores, ciclistas, nadadores y triatletas. Participaron de este estudio 39 corredores, 32 ciclistas, 30 nadadores y 38 triatletas. La Escala de Dependencia al Ejercicio (EDS) y el Inventario de Adicción al Ejercicio (EAI) fueron utilizados para evaluar la AE y clasificaron a los participantes en tres categorías: en riesgo de AE, no dependiente-sintomático y no dependiente-asintomático. La mayoría de los participantes se clasificaron como no dependiente-sintomático para AE. La puntuación EDS fue significativamente menor en nadadores en comparación con ciclistas y triatletas y la puntuación EAI total fue significativamente mayor en ciclistas en comparación con corredores. Por lo tanto, en ambos instrumentos, la mayoría de los participantes eran sintomáticos no dependientes para AE

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The aim of the present study was to evaluate and compare exercise addiction (EA) between runners, cyclists, swimmers, and triathletes. Took part in this study 39 runners, 32 cyclists, 30 swimmers and 38 triathletes. Exercise Dependence Scale (EDS), and the Exercise Addiction Inventory (EAI) was used to evaluate the EA and classified the participants into: at-risk for EA, nondependent-symptomatic, and nondependent-asymptomatic. Most participants were classified as nondependent symptomatic for EA. The EDS total score was significantly lower in the swimmers compared to the cyclists and triathletes and the EAI total score was significantly higher for cyclists compared to runners. Therefore, in both instruments, the majority of participants was nondependent symptomatic for EA.

O objetivo do presente estudo foi avaliar e comparar a dependência ao exercício (DE) entre corredores, ciclistas, nadado-res e triatletas. Participaram do estudo 39 corredores, 32 ciclistas, 30 nadadores e 38 triatletas. As escalas Exercise Dependence Scale (EDS) e Exercise Addiction Inventory (EAI) foram usadas para a ava-liação da DE e classificaram os participantes em três categorias: em risco de DE, não dependente sintomático e não dependente assintomático. A maioria dos participantes foram classificadas como não dependentes sintomáticos para DE. O escore da EDS foi significativamente menor nos nadadores comparado aos ciclistas e triatletas e o escore total da EAI foi significantemente maior nos ciclistas comparado aos corredores. Portanto, em ambos os ins-trumentos, a maioria dos participantes foi não dependente sinto-mático para DE.

El objetivo del presente estudio fue evaluar y comparar la adicción al ejercicio (AE) entre corredores, ciclistas, nadadores y triatletas. Participaron de este estudio 39 corredores, 32 ciclistas, 30 nadadores y 38 triatletas. La Escala de Dependencia al Ejercicio (EDS) y el Inventario de Adicción al Ejercicio (EAI) fueron utilizados para evaluar la AE y clasificaron a los participantes en tres categorías: en riesgo de AE, no dependiente-sintomático y no dependiente-asintomático. La mayoría de los participantes se clasificaron como no dependiente-sintomático para AE. La puntuación EDS fue significativamente menor en nadadores en comparación con ciclistas y triatletas y la puntuación EAI total fue significativamente mayor en ciclistas en comparación con corredores. Por lo tanto, en ambos instrumentos, la mayoría de los participantes eran sintomáticos no dependientes para AE.

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The effects of biodiversity on ecological processes have been experimentally evaluated mainly at the local scale under homogeneous conditions. To scale up experimentally based biodiversity-functioning relationships, there is an urgent need to understand how such relationships are affected by the environmental heterogeneity that characterizes larger spatial scales. Here, we tested the effects of an 800-m elevation gradient (a large-scale environmental factor) and forest habitat (a fine-scale factor) on litter diversity-decomposition relationships. To better understand local and landscape scale mechanisms, we partitioned net biodiversity effects into complementarity, selection, and insurance effects as applicable at each scale. We assembled different litter mixtures in aquatic microcosms that simulated natural tree holes, replicating mixtures across blocks nested within forest habitats (edge, interior) and elevations (low, mid, high). We found that net biodiversity and complementarity effects increased over the elevation gradient, with their strength modified by forest habitat and the identity of litter in mixtures. Complementarity effects at local and landscape scales were greatest for combinations of nutrient-rich and nutrient-poor litters, consistent with nutrient transfer mechanisms. By contrast, selection effects were consistently weak and negative at both scales. Selection effects at the landscape level were due mainly to nonrandom overyielding rather than spatial insurance effects. Our findings demonstrate that the mechanisms by which litter diversity affects decomposition are sensitive to environmental heterogeneity at multiple scales. This has implications for the scaling of biodiversity-ecosystem function relationships and suggests that future shifts in environmental conditions due to climate change or land use may impact the functioning of aquatic ecosystems.

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The aim of this study was to analyse the relationship between dating violence and emotional dependence in young university students in Ecuador by identifying differences based on sex. Using purposive non-probabilistic sampling, 3203 students were selected, of which 35.7% were men and 64.3% were women aged 16 to 48 (M = 21.50; SD = 2.82). Two psychological scales were applied: Questionnaire on Violence in Couples (CUVINO) and Questionnaire on Emotional Dependence (EDQ). According to the results obtained, based on sex, it was found that dating violence is a severe problem that both men and women experience. With regard to emotional dependence, women scored higher than men. In addition, emotional dependence was linked to dating violence. The implications of the results obtained for further research and for prevention and intervention programmes are presented, and the strengths and limitations of this study are detailed.

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Introducción: El consumo de drogas es un problema de salud que se presenta con mayor frecuencia en la población joven, pues su prevalencia aumenta cada día. En la actualidad existe preocupación sobre la percepción de riesgo del consumo de drogas en estudiantes universitarios. Objetivo: Describir la percepción de riesgo sobre el consumo de drogas en estudiantes universitarios de la provincia Manabí en Ecuador. Métodos: Investigación descriptiva y transversal; universo de 787 estudiantes universitarios de la provincia Manabí en Ecuador. La muestra quedó conformada por 259 estudiantes. Se utilizó la encuesta como técnica de recolección de datos. Como instrumento de investigación se utilizaron las encuestas escolares sobre el uso indebido de drogas de la oficina de las Naciones Unidas contra la droga y el delito. Se utilizó la estadística descriptiva para el procesamiento de los datos. Resultados: Se obtuvo una media de edad de 22,37 años, predominio del sexo femenino (65,25 %) y de estudiantes que consumen algún tipo de droga (79,92 %). El 91,30 % refirió consumo de drogas lícitas (tabaco 43,63 % y alcohol 61,39 %); el 31,26 % consumían drogas medicamentosas y el 23,29 % drogas ilícitas; de ellos, el 85,42 % refirió consumo de marihuana. El 32,04 % tenía una percepción baja sobre el riesgo de consumo de drogas. Conclusiones: En el grupo de estudiantes universitarios de la provincia Manabí que son investigados, existe un aumento del consumo de drogas lícitas, medicamentosas e ilícitas debido a una percepción deficiente del riesgo de consumo de estas sustancias.

Introduction: Drug use is a health problem that occurs more frequently in the young population; its prevalence increases every day. Currently, there is concern about the perception of risk of drug use in university students. Objective: Describe the risk perception of drug consumption in university students from the Manabí province in Ecuador. Methods: Descriptive and cross-sectional research; universe of 787 university students from the Manabí province in Ecuador. The sample was made up of 259 students. The survey was used as a data collection technique. The School Surveys on Drug Abuse from the United Nations Office on Drugs and Crime were used as a research instrument. Descriptive statistics were used to process the data. Results: An average age of 22.37 years was obtained, predominance of the female sex (65.25%) and students who consume some type of drug (79.92%). 91.30% reported consumption of legal drugs (tobacco 43.63% and alcohol 61.39%); 31.26% used medicinal drugs and 23.29% used illicit drugs; Of them, 85.42% reported marijuana use. 32.04% had a low perception of the risk of drug use. Conclusions: In the group of university students from the Manabí province who are investigated, there is an increase in the consumption of licit, medicinal and illicit drugs due to a poor perception of the risk of consumption of these substances.