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1.
Parasit Vectors ; 17(1): 166, 2024 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-38556881

RESUMEN

BACKGROUND: Malaria is a major public health concern in Ethiopia, and its incidence could worsen with the spread of the invasive mosquito species Anopheles stephensi in the country. This study aimed to provide updates on the distribution of An. stephensi and likely household exposure in Ethiopia. METHODS: Entomological surveillance was performed in 26 urban settings in Ethiopia from 2021 to 2023. A kilometer-by-kilometer quadrant was established per town, and approximately 20 structures per quadrant were surveyed every 3 months. Additional extensive sampling was conducted in 50 randomly selected structures in four urban centers in 2022 and 2023 to assess households' exposure to An. stephensi. Prokopack aspirators and CDC light traps were used to collect adult mosquitoes, and standard dippers were used to collect immature stages. The collected mosquitoes were identified to species level by morphological keys and molecular methods. PCR assays were used to assess Plasmodium infection and mosquito blood meal source. RESULTS: Catches of adult An. stephensi were generally low (mean: 0.15 per trap), with eight positive sites among the 26 surveyed. This mosquito species was reported for the first time in Assosa, western Ethiopia. Anopheles stephensi was the predominant species in four of the eight positive sites, accounting for 75-100% relative abundance of the adult Anopheles catches. Household-level exposure, defined as the percentage of households with a peridomestic presence of An. stephensi, ranged from 18% in Metehara to 30% in Danan. Anopheles arabiensis was the predominant species in 20 of the 26 sites, accounting for 42.9-100% of the Anopheles catches. Bovine blood index, ovine blood index and human blood index values were 69.2%, 32.3% and 24.6%, respectively, for An. stephensi, and 65.4%, 46.7% and 35.8%, respectively, for An. arabiensis. None of the 197 An. stephensi mosquitoes assayed tested positive for Plasmodium sporozoite, while of the 1434 An. arabiensis mosquitoes assayed, 62 were positive for Plasmodium (10 for P. falciparum and 52 for P. vivax). CONCLUSIONS: This study shows that the geographical range of An. stephensi has expanded to western Ethiopia. Strongly zoophagic behavior coupled with low adult catches might explain the absence of Plasmodium infection. The level of household exposure to An. stephensi in this study varied across positive sites. Further research is needed to better understand the bionomics and contribution of An. stephensi to malaria transmission.


Asunto(s)
Anopheles , Malaria Falciparum , Malaria Vivax , Malaria , Animales , Bovinos , Ecología , Etiopía/epidemiología , Malaria/epidemiología , Malaria Falciparum/epidemiología , Mosquitos Vectores
2.
3.
Philos Trans R Soc Lond B Biol Sci ; 379(1902): 20230010, 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38583479

RESUMEN

In the Anthropocene, intensifying ecological disturbances pose significant challenges to our predictive capabilities for ecosystem responses. Macroecology-which focuses on emergent statistical patterns in ecological systems-unveils consistent regularities in the organization of biodiversity and ecosystems. These regularities appear in terms of abundance, body size, geographical range, species interaction networks, or the flux of matter and energy. This paper argues for moving beyond qualitative resilience metaphors, such as the 'ball and cup', towards a more quantitative macroecological framework. We suggest a conceptual and theoretical basis for ecological resilience that integrates macroecology with a stochastic diffusion approximation constrained by principles of biological symmetry. This approach provides an alternative novel framework for studying ecological resilience in the Anthropocene. We demonstrate how our framework can effectively quantify the impacts of major disturbances and their extensive ecological ramifications. We further show how biological scaling insights can help quantify the consequences of major disturbances, emphasizing their cascading ecological impacts. The nature of these impacts prompts a re-evaluation of our understanding of resilience. Emphasis on regularities of ecological assemblages can help illuminate resilience dynamics and offer a novel basis to predict and manage the impacts of disturbance in the Anthropocene more efficiently. This article is part of the theme issue 'Ecological novelty and planetary stewardship: biodiversity dynamics in a transforming biosphere'.


Asunto(s)
Ecosistema , Resiliencia Psicológica , Biodiversidad , Geografía , Ecología
5.
PLoS One ; 19(4): e0298318, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38564574

RESUMEN

Cliodynamics is a still a relatively new research area with the purpose of investigating and modelling historical processes. One of its first important mathematical models was proposed by Turchin and called "Demographic-Fiscal Model" (DFM). This DFM was one of the first and is one of a few models that link population with state dynamics. In this work, we propose a possible alternative to the classical Turchin DFM, which contributes to further model development and comparison essential for the field of cliodynamics. Our "Demographic-Wealth Model" (DWM) aims to also model link between population and state dynamics but makes different modelling assumptions, particularly about the type of possible taxation. As an important contribution, we employ tools from nonlinear dynamics, e.g., existence theory for periodic orbits as well as analytical and numerical bifurcation analysis, to analyze the DWM. We believe that these tools can also be helpful for many other current and future models in cliodynamics. One particular focus of our analysis is the occurrence of Hopf bifurcations. Therefore, a detailed analysis is developed regarding equilibria and their possible bifurcations. Especially noticeable is the behavior of the so-called coexistence point. While changing different parameters, a variety of Hopf bifurcations occur. In addition, it is indicated, what role Hopf bifurcations may play in the interplay between population and state dynamics. There are critical values of different parameters that yield periodic behavior and limit cycles when exceeded, similar to the "paradox of enrichment" known in ecology. This means that the DWM provides one possible avenue setup to explain in a simple format the existence of secular cycles, which have been observed in historical data. In summary, our model aims to balance simplicity, linking to the underlying processes and the goal to represent secular cycles.


Asunto(s)
Modelos Biológicos , Modelos Teóricos , Ecología , Dinámicas no Lineales , Dinámica Poblacional
6.
Sci Rep ; 14(1): 7918, 2024 04 04.
Artículo en Inglés | MEDLINE | ID: mdl-38575633

RESUMEN

Generalist species, which exploit a wide range of food resources, are expected to be able to combine available resources as to attain their specific macronutrient ratio (percentage of caloric intake of protein, lipids and carbohydrates). Among mammalian predators, the red fox Vulpes vulpes is a widespread, opportunistic forager: its diet has been largely studied, outlining wide variation according to geographic and climatic factors. We aimed to check if, throughout the species' European range, diets vary widely in macronutrient composition or foxes can combine complementary foods to gain the same nutrient intake. First, we assessed fox's intake target in the framework of nutritional geometry. Secondly, we aimed to highlight the effects of unbalanced diets on fox density, which was assumed as a proxy for Darwinian fitness, as assessed in five areas of the western Italian Alps. Unexpectedly, the target macronutrient ratio of the fox (52.4% protein-, 38.7% lipid- and 8.9% carbohydrate energy) was consistent with that of hypercarnivores, such as wolves and felids, except for carbohydrate intakes in urban and rural habitats. The inverse relation between density and the deviation of observed macronutrient ratios from the intake target suggests that fox capability of surviving in a wide range of habitats may not be exempt from fitness costs and that nutrient availability should be regarded among the biotic factors affecting animal abundance and distribution.


Asunto(s)
Ecología , Zorros , Animales , Ecosistema , Carbohidratos
7.
Biom J ; 66(3): e2300279, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38576312

RESUMEN

Reduced major axis (RMA) regression, widely used in the fields of zoology, botany, ecology, biology, spectroscopy, and among others, outweighs the ordinary least square regression by relaxing the assumption that the covariates are without measurement errors. A Bayesian implementation of the RMA regression is presented in this paper, and the equivalence of the estimates of the parameters under the Bayesian and the frequentist frameworks is proved. This model-based Bayesian RMA method is advantageous since the posterior estimates, the standard deviations, as well as the credible intervals of the estimates can be obtained through Markov chain Monte Carlo methods directly. In addition, it is straightforward to extend to the multivariate RMA case. The performance of the Bayesian RMA approach is evaluated in the simulation study, and, finally, the proposed method is applied to analyze a dataset in the plantation.


Asunto(s)
Ecología , Teorema de Bayes , Simulación por Computador , Cadenas de Markov , Método de Montecarlo
8.
New Phytol ; 242(4): 1448-1475, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38581203

RESUMEN

Research on mycorrhizal symbiosis has been slowed by a lack of established study systems. To address this challenge, we have been developing Suillus, a widespread ecologically and economically relevant fungal genus primarily associated with the plant family Pinaceae, into a model system for studying ectomycorrhizal (ECM) associations. Over the last decade, we have compiled extensive genomic resources, culture libraries, a phenotype database, and protocols for manipulating Suillus fungi with and without their tree partners. Our efforts have already resulted in a large number of publicly available genomes, transcriptomes, and respective annotations, as well as advances in our understanding of mycorrhizal partner specificity and host communication, fungal and plant nutrition, environmental adaptation, soil nutrient cycling, interspecific competition, and biological invasions. Here, we highlight the most significant recent findings enabled by Suillus, present a suite of protocols for working with the genus, and discuss how Suillus is emerging as an important model to elucidate the ecology and evolution of ECM interactions.


Asunto(s)
Evolución Biológica , Modelos Biológicos , Micorrizas , Micorrizas/fisiología , Micorrizas/genética , Ecología , Simbiosis/genética , Basidiomycota/fisiología , Basidiomycota/genética
9.
PLoS Biol ; 22(4): e3002593, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38603520

RESUMEN

Understanding the evolution of coral endosymbiosis requires a predictive framework that integrates life-history theory and ecology with cell biology. The time has come to bridge disciplines and use a model systems approach to achieve this aim.


Asunto(s)
Antozoos , Animales , Antozoos/genética , Simbiosis , Ecología , Arrecifes de Coral , Evolución Biológica
10.
Parasitol Res ; 123(4): 187, 2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38634931

RESUMEN

Co-exposure to multiple parasites can alter parasite success and host life history when compared to single infections. These infection outcomes can be affected by the order of parasite arrival, the host immune response, and the interspecific interactions among co-infecting parasites. In this study, we examined how the arrival order of two trematode parasites, Schistosoma mansoni and Echinostoma caproni, influenced parasite ecology and the life history of their snail host, Biomphalaria glabrata. Snail hosts were exposed to E. caproni cercariae before, with, and after their exposure to S. mansoni miracidia. We then measured the effects of this timing on infection prevalence, infection intensity of E. caproni metacercariae, and cercarial output of S. mansoni, as well as on snail reproduction and survival. Snails infected only with S. mansoni and snails exposed to E. caproni after S. mansoni both shed more cercariae than simultaneously exposed snails. Additionally, S. mansoni prevalence was lower in snails that were first exposed to E. caproni compared to snails that were exposed to E. caproni after S. mansoni. Moreover, snails exposed to E. caproni before S. mansoni did not differ in their survival compared to control snails, whereas simultaneously exposed snails and snails exposed to E. caproni after S. mansoni had lower survival than control snails. Combined, this prevalence and survival data suggest a potential protective role of early E. caproni exposure. The timing of E. caproni exposure impacts S. mansoni establishment and reproduction, but host survival patterns are likely driven by S. mansoni prevalence alone.


Asunto(s)
Biomphalaria , Echinostoma , Parásitos , Animales , Cercarias , Ecología
11.
Fam Med Community Health ; 12(Suppl 3)2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38609088

RESUMEN

Storylines of Family Medicine is a 12-part series of thematically linked mini-essays with accompanying illustrations that explore the many dimensions of family medicine, as interpreted by individual family physicians and medical educators in the USA and elsewhere around the world. In 'I: framing family medicine-history, values, and perspectives', the authors address the following themes: 'Notes on Storylines of Family Medicine', 'Family medicine-the generalist specialty', 'Family medicine's achievements-a glass half full assessment', 'Family medicine's next 50 years-toward filling our glasses', 'Four enduring truths of family medicine', 'Names matter', 'Family medicine at its core' and 'The ecology of medical care.' May readers find much food for thought in these essays.


Asunto(s)
Medicina Familiar y Comunitaria , Médicos de Familia , Humanos , Ecología , Alimentos , Sistemas de Lectura
12.
Bull Environ Contam Toxicol ; 112(4): 61, 2024 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-38602522

RESUMEN

Total mercury (Hg) concentrations and carbon (δ13C) and nitrogen (δ15N) stable isotopes were quantified among aquatic invertebrate and sediment samples collected from Keuka Lake in New York's Finger Lakes region to evaluate temporal and spatial variability in Hg bioaccumulation and trophic ecology among these lower trophic levels. Hg concentrations ranged from 6.3 to 158.8 ng/g (dry wt) across dreissenid mussel, zooplankton, and juvenile (< 10 mm) and adult (≥ 10 mm) mysid shrimp (Mysis diluviana) samples. Hg concentrations were higher in samples collected from the western basin in 2015 relative to those for samples collected from this basin in 2022 (p < 0.001). While no specific mechanisms could be identified to explain this difference, higher δ15N values for zooplankton collected in 2015 support conclusions regarding the role of zooplankton trophic status on Hg concentrations in these populations. Spatial patterns in Hg concentrations were of generally low variability among samples collected from the lake's east, west and south basins in 2022. Trophic positions as inferred by δ15N were represented by adult mysids > juvenile mysids > large zooplankton (≥ 500 µm) > dreissenid mussels ≥ small zooplankton (64-500 µm). Differences were evident among the regression slopes describing the relationships between sample Hg concentrations and δ15N values across the lake's three basins (p = 0.028). However, this was primarily attributed to high δ15N values measured in dreissenid mussels collected from the south basin in 2022. Biota sediment accumulation factors ranged from 0.2 to 2.3 and were highest for adult M. diluviana but mysid δ13C values generally supported a pelagic pathway of Hg exposure relative to benthic sediments. Overall, these results provide additional support regarding the contributions of lower trophic levels to Hg biomagnification in aquatic food-webs.


Asunto(s)
Cadena Alimentaria , Mercurio , Animales , Bioacumulación , Lagos , Ecología , Zooplancton
13.
Curr Biol ; 34(7): R269-R270, 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38593767

RESUMEN

High-resolution object vision - the ability to separate, classify, and interact with specific objects in the environment against the visual background - has only been conclusively shown to have evolved in three of the thirty-five animal phyla: chordates, arthropods, and mollusks (cephalopods)1. However, alciopid polychaetes (Phyllodocidae, Alciopini), which possess a pair of bulbous camera-type eyes, have also been hypothesized to achieve high acuity. In this study, we examined three species of night-active pelagic alciopids from the Mediterranean Sea. Our optical, morphological, and electrophysiological investigations show that their eyes have high spatial acuity and temporal resolution, supporting the notion that they are capable of active, high-resolution object vision. These results encourage interesting hypotheses about the visual ecology of these enigmatic polychaetes.


Asunto(s)
Artrópodos , Visión Ocular , Animales , Ojo/anatomía & histología , Moluscos , Ecología
14.
Curr Biol ; 34(7): R273-R275, 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38593769

RESUMEN

Local and indigenous communities often have an intimate connection to nature that is reflected in their ecological knowledge and practices. A new study shows that local ecological knowledge can transform the scientific understanding of an ecological network.


Asunto(s)
Frutas , Conocimiento , Ecología , Conservación de los Recursos Naturales
15.
Naturwissenschaften ; 111(3): 22, 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38607380

RESUMEN

Documentation of cryptic trilobite behavior has presented important insights into the paleoecology of this fully extinct arthropod group. One such example is the preservation of trilobites inside the remains of larger animals. To date, evidence for trilobites within cephalopods, gastropods, hyoliths, and other trilobites has been presented. Importantly, most of these interactions show trilobite molts, suggesting that trilobites used larger animals for protection during molting. To expand the record of molted trilobites within cephalopods, we present a unique case of a Toxochasmops vormsiensis trilobite within the body chamber of a Gorbyoceras textumaraneum nautiloid from the Upper Ordovician Kõrgessaare Formation of Estonia. By examining this material, we present new insights into the ecology of pterygometopid trilobites, highlighting how these forms used large cephalopods as areas to successfully molt.


Asunto(s)
Artrópodos , Muda , Animales , Estonia , Ecología
16.
PLoS One ; 19(4): e0298953, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38635571

RESUMEN

The Great Wall Villages (GWVs) are linked to the Great Wall in history, culture, and ecology. The cultural landscape resilience of Great Wall Villages (CLRGWVs) is distinctly significant. However, it is influenced by urbanization, pollution, and a lack of awareness of cultural landscape protection. Therefore, conservation and development practices still lack scientific strategies and guidance. This study proposes a new assessment system to quantify CLRGWVs, an analysis of the main influencing factors of resilience, and optimization paths to maintain sustainable development. Based on the socio-ecological system, this research designed the assessment with three criteria, eleven factors, and thirty-three indexes from the perspective of CLRGWVs. Furthermore, a demonstration test was constructed in Ningyuanbao Village, Dushikou Village, and Longmensuo Village in Chicheng County, Hebei Province, China. The results showed that there is some disparity between the three GWVs, with the resilience score of Dushikou Village being the highest in terms of resistance and learning. In contrast, Ningyuanbao Village's resilience score is the lowest since resistance, recovery, and learning capacity are lower than in Dushikou and Longmensuo. Some influencing factors were found to be highly related to adaptive capacity. Lastly, some low-resilience aspects were identified as critical improvement targets for which corresponding optimization strategies should be proposed. This could be applied to streamline resilience optimization paths according to local conditions. This paper provides new ideas and directions for dealing with the sustainable development of villages and the conservation of cultural landscapes. It will also help villages deal with the relationship between socio-economic development and the conservation of cultural landscapes.


Asunto(s)
Conservación de los Recursos Naturales , Resiliencia Psicológica , Ecología , Ecosistema , Desarrollo Sostenible , China
17.
PeerJ ; 12: e17221, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38638157

RESUMEN

Background: Soil organic nitrogen (SON) levels can respond effectively to crop metabolism and are directly related to soil productivity. However, simultaneous comparisons of SON dynamics using isotopic tracing in diverse agroecosystems are lacking, especially in karst areas with fragile ecology. Methods: To better understand the response of SON dynamics to environmental changes under the coupling of natural and anthropogenic disturbances, SON contents and their stable N isotope (δ15NSON) compositions were determined in abandoned cropland (AC, n = 16), grazing shrubland (GS, n = 11), and secondary forest land (SF, n = 20) from a typical karst area in southwest China. Results: The SON contents in the SF (mean: 0.09%) and AC (mean: 0.10%) profiles were obviously lower than those in the GS profile (mean: 0.31%). The δ15NSON values ranged from 4.35‰-7.59‰, 3.79‰-7.23‰, and 1.87‰-7.08‰ for the SF, AC, and GS profiles, respectively. Decomposition of organic matter controlled the SON variations in the secondary forest land by the covered vegetation, and that in the grazing shrubland by goat excreta. δ15NSON ranges were controlled by the covered vegetation, and the δ15NSON fractionations during SON transformation were influenced by microorganisms in all surface soil. Conclusions: The excreta of goats that contained 15N-enriched SON induced a heavier δ15NSON composition in the grazed shrubland. Long-term cultivation consumes SON, whereas moderate grazing increases SON content to reduce the risk of soil degradation. This study suggests that optimized crop-livestock production may benefit the sustainable development of agroecosystems in karst regions.


Asunto(s)
Nitrógeno , Suelo , Nitrógeno/análisis , Suelo/química , Bosques , Ecología , China
18.
Proc Biol Sci ; 291(2021): 20231422, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38654647

RESUMEN

Researchers in the biological and behavioural sciences are increasingly conducting collaborative, multi-sited projects to address how phenomena vary across ecologies. These types of projects, however, pose additional workflow challenges beyond those typically encountered in single-sited projects. Through specific attention to cross-cultural research projects, we highlight four key aspects of multi-sited projects that must be considered during the design phase to ensure success: (1) project and team management; (2) protocol and instrument development; (3) data management and documentation; and (4) equitable and collaborative practices. Our recommendations are supported by examples from our experiences collaborating on the Evolutionary Demography of Religion project, a mixed-methods project collecting data across five countries in collaboration with research partners in each host country. To existing discourse, we contribute new recommendations around team and project management, introduce practical recommendations for exploring the validity of instruments through qualitative techniques during piloting, highlight the importance of good documentation at all steps of the project, and demonstrate how data management workflows can be strengthened through open science practices. While this project was rooted in cross-cultural human behavioural ecology and evolutionary anthropology, lessons learned from this project are applicable to multi-sited research across the biological and behavioural sciences.


Asunto(s)
Ciencias de la Conducta , Recolección de Datos , Humanos , Recolección de Datos/métodos , Comparación Transcultural , Proyectos de Investigación , Ecología/métodos
19.
Nature ; 628(8009): 692, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38658681
20.
Ying Yong Sheng Tai Xue Bao ; 35(3): 769-779, 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38646765

RESUMEN

Exploring the correlations between ecosystem service value (ESV) and landscape ecological risk and the driving factors of their spatial variations is crucial for maintaining regional ecological security and promoting sustainable human well-being. We carried out a grid resampling size of 5 km×5 km assessment units of Jilin Pro-vince based on the remote sensing monitoring data of land use in 2000, 2005, 2010, 2015, and 2020. We quantitatively evaluated the landscape ecological risk and ESV, and analyzed their spatial-temporal variations. Employing bivariate spatial autocorrelation analysis and the geographical detector models, we examined the correlation between the landscape ecological risk and ESV and explored the driving factors for their spatial variations. The results showed that ESV in Jilin Province decreased from 385.895 billion yuan to 378.211 billion yuan during 2000-2020. The eastern region was dominated by extremely low risk, medium risk, and low risk areas. In contrast, the western region was mainly composed of extremely high risk and high risk areas. There was a significant negative correlation and spatial negative correlation between landscape ecological risk and ESV in Jilin Province. Human activity and land use type were the important driving factors for spatial differentiation in both landscape ecological risk and ESV. Our findings suggested that scientific land use regulation and appropriate control of human activities are critically needed to optimize Jilin Province's ecological environment.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Monitoreo del Ambiente , China , Monitoreo del Ambiente/métodos , Tecnología de Sensores Remotos , Medición de Riesgo , Ecología , Análisis Espacial , Actividades Humanas
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