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1.
Glob Chang Biol ; 30(6): e17375, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38895806

RESUMEN

Islands are biodiversity hotspots that host unique assemblages. However, a substantial proportion of island species are threatened and their long-term survival is uncertain. Identifying and preserving vulnerable species has become a priority, but it is also essential to combine this information with other facets of biodiversity like functional diversity, to understand how future extinctions might affect ecosystem stability and functioning. Focusing on mammals, we (i) assessed how much functional space would be lost if threatened species go extinct, (ii) determined the minimum number of extinctions that would cause a significant functional loss, (iii) identified the characteristics (e.g., biotic, climatic, geographic, or orographic) of the islands most vulnerable to future changes in the functional space, and (iv) quantified how much of that potential functional loss would be offset by introduced species. Using trait information for 1474 mammal species occurring in 318 islands worldwide, we built trait probability density functions to quantify changes in functional richness and functional redundancy in each island if the mammals categorized by IUCN as threatened disappeared. We found that the extinction of threatened mammals would reduce the functional space in 63% of the assessed islands, although these extinctions in general would cause a reduction of less than 15% of their overall functional space. Also, on most islands, the extinction of just a few species would be sufficient to cause a significant loss of functional diversity. The potential functional loss would be higher on small, isolated, and/or species-rich islands, and, in general, the functional space lost would not be offset by introduced species. Our results show that the preservation of native species and their ecological roles remains crucial for maintaining the current functioning of island ecosystems. Therefore, conservation measures considering functional diversity are imperative to safeguard the unique functional roles of threatened mammal species on islands.


Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales , Especies en Peligro de Extinción , Extinción Biológica , Islas , Mamíferos , Animales , Mamíferos/fisiología , Especies Introducidas
2.
Sci Data ; 11(1): 368, 2024 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-38605058

RESUMEN

Globally, there is a concerning decline in many insect populations, and this trend likely extends to all arthropods, potentially impacting unique island biota. Native non-endemic and endemic species on islands are under threat due to habitat destruction, with the introduction of exotic, and potentially invasive, species, further contributing to this decline. While long-term studies of plants and vertebrate fauna are available, long-term arthropod datasets are limited, hindering comparisons with better-studied taxa. The Biodiversity of Arthropods of the Laurisilva of the Azores (BALA) project has allowed gathering comprehensive data since 1997 in the Azorean Islands (Portugal), using standardised sampling methods across islands. The dataset includes arthropod counts from epigean (pitfall traps) and canopy-dwelling (beating samples) communities, enriched with species information, biogeographic origins, and IUCN categories. Metadata associated with the sample protocol and events, like sample identifier, archive number, sampled tree species, and trap type are also recorded. The database is available in multiple formats, including Darwin Core, which facilitates the ecological analysis of pressing environmental concerns, such as arthropod population declines and biological invasions.


Asunto(s)
Artrópodos , Bosques , Animales , Biodiversidad , Ecosistema , Especies Introducidas , Azores
3.
Plants (Basel) ; 12(11)2023 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-37299191

RESUMEN

The common bean has received attention as a model plant for legume studies, but little information is available about the morphology of its pods and the relation of this morphology to the loss of seed dispersal and/or the pod string, which are key agronomic traits of legume domestication. Dehiscence is related to the pod morphology and anatomy of pod tissues because of the weakening of the dorsal and ventral dehiscence zones and the tensions of the pod walls. These tensions are produced by the differential mechanical properties of lignified and non-lignified tissues and changes in turgor associated with fruit maturation. In this research, we histologically studied the dehiscence zone of the ventral and dorsal sutures of the pod in two contrasting genotypes for the dehiscence and string, by comparing different histochemical methods with autofluorescence. We found that the secondary cell wall modifications of the ventral suture of the pod were clearly different between the dehiscence-susceptible and stringy PHA1037 and the dehiscence-resistant and stringless PHA0595 genotypes. The susceptible genotype had cells of bundle caps arranged in a more easily breakable bowtie knot shape. The resistant genotype had a larger vascular bundle area and larger fibre cap cells (FCCs), and due to their thickness, the external valve margin cells were significantly stronger than those from PHA1037. Our findings suggest that the FCC area, and the cell arrangement in the bundle cap, might be partial structures involved in the pod dehiscence of the common bean. The autofluorescence pattern at the ventral suture allowed us to quickly identify the dehiscent phenotype and gain a better understanding of cell wall tissue modifications that took place along the bean's evolution, which had an impact on crop improvement. We report a simple autofluorescence protocol to reliably identify secondary cell wall organization and its relationship to the dehiscence and string in the common bean.

4.
Trop Med Infect Dis ; 8(4)2023 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-37104340

RESUMEN

BACKGROUND: Chikungunya virus (CHIKV) diagnosis has become a challenge for primary care physicians in areas where the Zika virus and/or Dengue virus are present. Case definitions for the three arboviral infections overlap. METHODS: A cross-sectional analysis was carried out. A bivariate analysis was made using confirmed CHIKV infection as the outcome. Variables with significant statistical association were included in an agreement consensus. Agreed variables were analyzed in a multiple regression model. The area under the receiver operating characteristic (ROC) curve was calculated to determine a cut-off value and performance. RESULTS: 295 patients with confirmed CHIKV infection were included. A screening tool was created using symmetric arthritis (4 points), fatigue (3 points), rash (2 points), and ankle joint pain (1 point). The ROC curve identified a cut-off value, and a score ≥ 5.5 was considered positive for identifying CHIKV patients with a sensibility of 64.4% and a specificity of 87.4%, positive predictive value of 85.5%, negative predictive value of 67.7%, area under the curve of 0.72, and an accuracy of 75%. CONCLUSION: We developed a screening tool for CHIKV diagnosis using only clinical symptoms as well as proposed an algorithm to aid the primary care physician.

6.
J Environ Manage ; 337: 117713, 2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-36958277

RESUMEN

Roughly 2 billion ha of land are degraded and in need of ecological restoration worldwide. Active restoration frequently involves revegetation, which leads to the dilemma of whether to conduct direct seeding or to plant nursery-grown seedlings. The choice of revegetation method can regulate plant survival and performance, with economic implications that ultimately feed back to our capacity to conduct restoration. We followed a peer-reviewed protocol to develop a systematic map that collates, describes and catalogues the available studies on how seeding compares to planting in achieving restoration targets. We compiled a database with the characteristics of all retrieved studies, which can be searched to identify studies of particular locations and habitats, objectives of restoration, plant material, technical aspects, and outcomes measured. The search was made in eight languages and retrieved 3355 publications, of which 178 were retained. The systematic map identifies research gaps, such as a lack of studies in the global South, in tropical rainforests, and covering a long time period, which represent opportunities to expand field-based research. Additionally, many studies overlooked reporting on important technical aspects such as seed provenance and nursery cultivation methods, and others such as watering or seedling protection were more frequently applied for planting than for seeding, which limits our capacity to learn from past research. Most studies measured outcomes related to the target plants but avoided measuring general restoration outcomes or economic aspects. This represents a relevant gap in research, as the choice of revegetation method is greatly based on economic aspects and the achievement of restoration goals goes beyond the establishment of plants. Finally, we identified a substantial volume of studies conducted in temperate regions and over short periods (0-5 y). This research cluster calls for a future in-depth synthesis, potentially through meta-analysis, to reveal the overall balance between seeding and planting and assess whether the response to this question is mediated by species traits, environmental characteristics, or technical aspects. Besides identifying research clusters and gaps, the systematic map database allows managers to find the most relevant scientific literature on the appropriateness of seeding vs. planting for particular conditions, such as certain species or habitats.


Asunto(s)
Ecosistema , Plantas , Plantones , Semillas
7.
BMJ Open ; 13(3): e069246, 2023 03 23.
Artículo en Inglés | MEDLINE | ID: mdl-36958782

RESUMEN

Syndemics are a framework that documents health inequities and vulnerabilities in populations with rheumatic diseases. Compared with other approaches, syndemics are able to conjunctly consider epidemiological, biological, sociodemographic and economic factors, and their interactions. OBJECTIVE: To estimate health inequity and vulnerability among Indigenous and non-Indigenous populations with rheumatic and musculoskeletal diseases (RMD) in Latin America using the syndemic approach. DESIGN: This is a secondary analysis of a previously published large-scale study on the prevalence of RMD. SETTING: Studies carried out in five Latin American countries (Argentina, Colombia, Ecuador, Mexico and Venezuela). Health inequity and vulnerability in RMD were identified through a syndemic approach using network and cluster analysis. PARTICIPANTS: A total of 44 560 individuals were studied: 29.78% self-identified as Indigenous, 60.92% were female, the mean age was 43.25 years. Twenty clusters were identified in the Indigenous population and 17 in the non-Indigenous population. RESULTS: The variables associated with RMD among Indigenous populations were rurality, public health system, high joint biomechanical stress, greater pain, disability and alcoholism; and among non-Indigenous people they were being a woman, urban origin, older age, private health system, joint biomechanical stress, greater pain and disability. We identified different health inequities among patients with RMD (ie, lower educational attainment, more comorbidities), associated with factors such as Indigenous self-identification and rural residence. CONCLUSIONS: A syndemic approach enables us to identify health inequities in RMD, as shown by higher prevalence of comorbidities, disability and socioeconomic factors like lower educational attainment. These inequities exist for the overall population of patients with RMD, although it is more evident in Indigenous groups with added layers of vulnerability.


Asunto(s)
Enfermedades Reumáticas , Sindémico , Humanos , Femenino , Adulto , Masculino , América Latina/epidemiología , Enfermedades Reumáticas/epidemiología , México , Dolor
8.
Ecol Evol ; 13(2): e9828, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36818530

RESUMEN

Species' environmental requirements and large-scale spatial and evolutionary processes determine the structure and composition of local communities. However, ecological interactions also have major effects on community assembly at landscape and local scales. We evaluate whether two xerophytic shrub communities occurring in SW Portugal follow constrained ecological assembly dynamics throughout large geographical extents, or their composition is rather driven by species' individualistic responses to environmental and macroecological constraints. Inland dune xerophytic shrub communities were characterized in 95 plots. Then, we described the main gradients of vegetation composition and assessed the relevance of biotic interactions. We also characterized the habitat suitability of the dominant species, Stauracanthus genistoides, and Ulex australis, to map the potential distribution of the xerophytic shrub communities. Finally, we examined the relationships between the vegetation gradients and a broad set of explanatory variables to identify the relative importance of each factor driving changes in community composition. We found that xerophytic shrubs follow uniform successional patterns throughout the whole geographical area studied, but each community responds differently to the main environmental gradients in each region. Soil organic matter is the main determinant of community variations in the northern region, Setúbal Peninsula, whereas aridity is so in the South/South-Western region. In contrast, in the central region, Comporta, the variation between S. genistoides and U. australis communities is explained mainly by aridity and temperature seasonality, followed by the individualistic responses of the dominant species and soil organic matter. Overall, these results indicate that, the relative importance of the main factors causing community-level responses varies according to regional processes and the suitability of the environmental conditions for the dominant species in these communities. These responses are also determined by intrinsic community mechanisms that result in a high degree of similarity in the gradient-driven community stages in different regions.

9.
J Anim Ecol ; 92(1): 44-65, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36443916

RESUMEN

Traits are key for understanding the environmental responses and ecological roles of organisms. Trait approaches to functional ecology are well established for plants, whereas consistent frameworks for animal groups are less developed. Here we suggest a framework for the study of the functional ecology of animals from a trait-based response-effect approach, using dung beetles as model system. Dung beetles are a key group of decomposers that are important for many ecosystem processes. The lack of a trait-based framework tailored to this group has limited the use of traits in dung beetle functional ecology. We review which dung beetle traits respond to the environment and affect ecosystem processes, covering the wide range of spatial, temporal and biological scales at which they are involved. Dung beetles show trait-based responses to variation in temperature, water, soil properties, trophic resources, light, vegetation structure, competition, predation and parasitism. Dung beetles' influence on ecosystem processes includes trait-mediated effects on nutrient cycling, bioturbation, plant growth, seed dispersal, other dung-based organisms and parasite transmission, as well as some cases of pollination and predation. We identify 66 dung beetle traits that are either response or effect traits, or both, pertaining to six main categories: morphology, feeding, reproduction, physiology, activity and movement. Several traits pertain to more than one category, in particular dung relocation behaviour during nesting or feeding. We also identify 136 trait-response and 77 trait-effect relationships in dung beetles. No response to environmental stressors nor effect over ecological processes were related with traits of a single category. This highlights the interrelationship between the traits shaping body-plans, the multi-functionality of traits, and their role linking responses to the environment and effects on the ecosystem. Despite current developments in dung beetle functional ecology, many knowledge gaps remain, and there are biases towards certain traits, functions, taxonomic groups and regions. Our framework provides the foundations for the thorough development of trait-based dung beetle ecology. It also serves as an example framework for other taxa.


Asunto(s)
Escarabajos , Ecosistema , Animales , Escarabajos/fisiología , Suelo/química , Plantas , Semillas , Biodiversidad , Ecología
10.
Angew Chem Int Ed Engl ; 61(42): e202206919, 2022 10 17.
Artículo en Inglés | MEDLINE | ID: mdl-35876263

RESUMEN

Points for accumulation in nanoscale topography (PAINT) allows practically unlimited measurements in localisation microscopy but is limited by background fluorescence at high probe concentrations, especially in volumetric imaging. We present reservoir-PAINT (resPAINT), which combines PAINT and active control of probe photophysics. In resPAINT, an activatable probe "reservoir" accumulates on target, enabling a 50-fold increase in localisation rate versus conventional PAINT, without compromising contrast. By combining resPAINT with large depth-of-field microscopy, we demonstrate super-resolution imaging of entire cell surfaces. We generalise the approach by implementing various switching strategies and 3D imaging techniques. Finally, we use resPAINT with a Fab to image membrane proteins, extending the operating regime of PAINT to include a wider range of biological interactions.


Asunto(s)
ADN , Imagen Individual de Molécula , Imagenología Tridimensional , Proteínas de la Membrana , Microscopía Fluorescente/métodos , Imagen Individual de Molécula/métodos
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