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1.
Exp Hematol ; 138: 104587, 2024 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-39074529

RESUMEN

A diverse array of protocols have been established for the directed differentiation of human pluripotent stem cells (hPSCs) into a variety of cell types, including blood cells, for modeling development and disease, and for the development of cell-based therapeutics. These protocols recapitulate various signaling requirements essential for the establishment of the hematopoietic systems during embryonic development. However, in many instances, the functional properties of those progenitors, and their relevance to human development, remains unclear. The human embryo, much like other vertebrate model organisms, generates hematopoietic cells via successive anatomical location- and time-specific waves, each yielding cells with distinct functional and molecular characteristics. Each of these progenitor "waves" is characterized at the time of emergence of the direct hematopoietic progenitor in the vasculature, the hemogenic endothelial cell (HEC). Critically, despite decades of study in model organisms, the origins of each of these HEC populations remain unclear. Fortunately, through the directed differentiation of hPSCs, recent insights have been made into the earliest origins of each HEC population, revealing that each arises from transcriptionally and phenotypically distinct subsets of nascent mesoderm. Here, we outline the protocols to generate each mesodermal and HEC population via the formation of embryoid bodies and subsequent stage-specific signal manipulation. Through implementation of these discrete signal manipulations, it is possible to obtain human HEC populations that are exclusively extraembryonic-like or exclusively intraembryonic-like, enabling comparative developmental biology studies or specific translational applications.

2.
Bioscience ; 74(6): 383-392, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-39055369

RESUMEN

The scarcity of long-term observational data has limited the use of statistical or machine-learning techniques for predicting intraannual ecological variation. However, time-stamped citizen-science observation records, supported by media data such as photographs, are increasingly available. In the present article, we present a novel framework based on the concept of relative phenological niche, using machine-learning algorithms to model observation records as a temporal sample of environmental conditions in which the represented ecological phenomenon occurs. Our approach accurately predicts the temporal dynamics of ecological events across large geographical scales and is robust to temporal bias in recording effort. These results highlight the vast potential of citizen-science observation data to predict ecological phenomena across space, including in near real time. The framework is also easily applicable for ecologists and practitioners already using machine-learning and statistics-based predictive approaches.

7.
Nat Commun ; 14(1): 4304, 2023 07 20.
Artículo en Inglés | MEDLINE | ID: mdl-37474503

RESUMEN

Climate change has been associated with both latitudinal and elevational shifts in species' ranges. The extent, however, to which climate change has driven recent range shifts alongside other putative drivers remains uncertain. Here, we use the changing distributions of 378 European breeding bird species over 30 years to explore the putative drivers of recent range dynamics, considering the effects of climate, land cover, other environmental variables, and species' traits on the probability of local colonisation and extinction. On average, species shifted their ranges by 2.4 km/year. These shifts, however, were significantly different from expectations due to changing climate and land cover. We found that local colonisation and extinction events were influenced primarily by initial climate conditions and by species' range traits. By contrast, changes in climate suitability over the period were less important. This highlights the limitations of using only climate and land cover when projecting future changes in species' ranges and emphasises the need for integrative, multi-predictor approaches for more robust forecasting.


Asunto(s)
Aves , Cambio Climático , Animales , Ecosistema
8.
Med. segur. trab ; 69(271): 108-123, 30 jun 2023. tab
Artículo en Español | IBECS | ID: ibc-228167

RESUMEN

Introducción: El berilio es un metal que por sus propiedades físico-químicas es utilizado en la industria para la fabricación de diferentes productos comerciales y de alta tecnología. La exposición laboral al berilio se relaciona con la aparición de neoplasia de pulmón, siendo esta enfermedad la primera causa de muerte por cáncer a nivel mundial.Objetivos: Revisar la literatura científica existente en relación con la exposición laboral al berilio y/o sus compues-tos y la neoplasia de pulmón.Método: Revisión sistemática de la literatura científica recogida en las bases de datos bibliográficas MEDLINE (vía PubMed), EMBASE, Web Of Science, Scopus, Cochrane Library, Índice Bibliográfico Español en Ciencias de la Salud (IBECS), Literatura Latinoamericana y del Caribe en Ciencias de la Salud (LILACS) y Medicina en Español (MEDES). Los términos utilizados como descriptores fueron: “Occupational Exposure”, “Occupational Diseases”, “Beryllium” y “Lung Neoplasms”. La búsqueda se completó con otros términos en texto libre y no se emplearon filtros (límites). La determinación de la calidad de los artículos seleccionados se llevó a cabo empleando la guía STROBE.Resultados: Se recuperaron 180 referencias, de las que se seleccionaron a texto completo 11 artículos tras aplicar los criterios de inclusión y exclusión. En estos estudios se describe la asociación entre exposición laboral al berilio y el desarrollo de neoplasia de pulmón.Conclusiones: Existe una asociación entre la exposición laboral al berilio y/o sus compuestos y la neoplasia de pulmón. Considerando el bajo número de estudios publicados y sus limitaciones, sería necesario realizar nuevos estudios que se adapten a las condiciones de la industria actual del berilio, teniendo en cuenta la solubilidad de sus compuestos, así como la identificación de sectores industriales y colectivos de trabajadores expuestos al mismo que aún no hayan sido estudiados (AU)


Introduction: Beryllium is an element that, due to its physical and chemical characteristics, is used in the manufac-turing of different commercial products and the high-tech industry. Laboral exposure to beryllium is associated with higher incidence of lung cancer, being this disease the leading cause of cancer death worldwide.Objectives: To review the existing scientific literature on the occurrence of occupational exposure to beryllium and/or its compounds and lung cancer.Method: Systematic review of the scientific literature collected in the bibliographic databases MEDLINE (via PubMed), EMBASE, Web Of Science, Scopus, Cochrane Library, Spanish Bibliographic Index in Health Sciences (IBECS), Latin American and Caribbean Literature in Health Sciences (LILACS) and Medicine in Spanish (MEDES). The terms used as descriptors were: “Occupational Exposure”, “Occupational Diseases”, “Beryllium” and “Lung Neo-plasms”. The search was completed with other terms in free text and no filters (limits) were used. The determination of the quality of the selected articles was carried out using the STROBE guide.Results: 180 references were retrieved, of which 11 articles could be obtained in full text after applying the inclusion and exclusion criteria. These studies describe the association between occupational exposure to beryllium and the development of lung cancer.Conclusions: There is an association between exposure to beryllium and/or its compounds and the development of lung cancer. However, considering the low number of published studies and their limitations, further studies should be carried out, which may be adapted to the current circumstances of the beryllium industry, taking into account the solubility of the beryllium compounds and the identification of industries and populations of workers exposed to beryllium that have not yet been studied (AU)


Asunto(s)
Humanos , Enfermedades Profesionales/inducido químicamente , Exposición Profesional/efectos adversos , Neoplasias Pulmonares/inducido químicamente , Berilio/efectos adversos
10.
Nat Commun ; 13(1): 7837, 2022 12 22.
Artículo en Inglés | MEDLINE | ID: mdl-36550094

RESUMEN

Ungulate populations are increasing across Europe with important implications for forest plant communities. Concurrently, atmospheric nitrogen (N) deposition continues to eutrophicate forests, threatening many rare, often more nutrient-efficient, plant species. These pressures may critically interact to shape biodiversity as in grassland and tundra systems, yet any potential interactions in forests remain poorly understood. Here, we combined vegetation resurveys from 52 sites across 13 European countries to test how changes in ungulate herbivory and eutrophication drive long-term changes in forest understorey communities. Increases in herbivory were associated with elevated temporal species turnover, however, identities of winner and loser species depended on N levels. Under low levels of N-deposition, herbivory favored threatened and small-ranged species while reducing the proportion of non-native and nutrient-demanding species. Yet all these trends were reversed under high levels of N-deposition. Herbivores also reduced shrub cover, likely exacerbating N effects by increasing light levels in the understorey. Eutrophication levels may therefore determine whether herbivory acts as a catalyst for the "N time bomb" or as a conservation tool in temperate forests.


Asunto(s)
Bosques , Herbivoria , Plantas , Biodiversidad , Nitrógeno
12.
Proc Biol Sci ; 288(1958): 20211394, 2021 09 08.
Artículo en Inglés | MEDLINE | ID: mdl-34465240

RESUMEN

Human encroachment into natural habitats is typically followed by conflicts derived from wildlife damage to agriculture and livestock. Spatial risk modelling is a useful tool to gain the understanding of wildlife damage and mitigate conflicts. Although resource selection is a hierarchical process operating at multiple scales, risk models usually fail to address more than one scale, which can result in the misidentification of the underlying processes. Here, we addressed the multi-scale nature of wildlife damage occurrence by considering ecological and management correlates interacting from household to landscape scales. We studied brown bear (Ursus arctos) damage to apiaries in the North-eastern Carpathians as our model system. Using generalized additive models, we found that brown bear tendency to avoid humans and the habitat preferences of bears and beekeepers determine the risk of bear damage at multiple scales. Damage risk at fine scales increased when the broad landscape context also favoured damage. Furthermore, integrated-scale risk maps resulted in more accurate predictions than single-scale models. Our results suggest that principles of resource selection by animals can be used to understand the occurrence of damage and help mitigate conflicts in a proactive and preventive manner.


Asunto(s)
Animales Salvajes , Ursidae , Agricultura , Animales , Ecosistema , Humanos
15.
Nat Ecol Evol ; 5(7): 896-906, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33986541

RESUMEN

Monitoring global biodiversity from space through remotely sensing geospatial patterns has high potential to add to our knowledge acquired by field observation. Although a framework of essential biodiversity variables (EBVs) is emerging for monitoring biodiversity, its poor alignment with remote sensing products hinders interpolation between field observations. This study compiles a comprehensive, prioritized list of remote sensing biodiversity products that can further improve the monitoring of geospatial biodiversity patterns, enhancing the EBV framework and its applicability. The ecosystem structure and ecosystem function EBV classes, which capture the biological effects of disturbance as well as habitat structure, are shown by an expert review process to be the most relevant, feasible, accurate and mature for direct monitoring of biodiversity from satellites. Biodiversity products that require satellite remote sensing of a finer resolution that is still under development are given lower priority (for example, for the EBV class species traits). Some EBVs are not directly measurable by remote sensing from space, specifically the EBV class genetic composition. Linking remote sensing products to EBVs will accelerate product generation, improving reporting on the state of biodiversity from local to global scales.


Asunto(s)
Benchmarking , Ecosistema , Biodiversidad
16.
Medisur ; 18(2): 177-184, mar.-abr. 2020. tab, graf
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1125193

RESUMEN

RESUMEN Introducción: Las arbovirosis son enfermedades que han emergido como problema de salud pública. Objetivo: Identificar modificaciones en indicadores hospitalarios en relación con la aparición de eventos de arbovirosis en la provincia. Metodo: indicadores hospitalarios seleccionados en el período 2014-2018: índice ocupacional, estadía hospitalaria, índice de rotación e intervalo de sustitución. Los métodos matemáticos utilizados para el procesamiento de la información fueron la Mediana y la Media aritmética. Los resultados se expresaron en gráficos y tablas. Resultados: El índice ocupacional experimentó una tendencia al ascenso al ser el más elevado en el año 2018 con un 66.9% afectando los servicios de neuropediatría (88.1) y pediatría general (78). La estadía hospitalaria mostró un notable incremento en el año 2018 aunque no sobrepasó los 4 días ni en los servicios que atendieron a estos pacientes, lo cual pudo corresponderse con dificultades en la vigilancia activa de casos. El índice de rotación e intervalo de sustitución estuvieron acorde al índice ocupacional, estadía hospitalaria y al tipo de hospital. Conclusiones: Se advirtieron modificaciones en los indicadores hospitalarios relacionados con el uso eficiente del recurso cama siendo más evidentes en el año 2018, período en el que se declararon casos de dengue en la provincia.


ABSTRACT Introduction: Arboviruses have emerged as a public health problem. Objective: To identify modifications in hospital indicators in relation to the occurrence of arbovirus events in the province. Method: hospital indicators selected in the 2014-2018 period: occupational index, hospital stay, turnover rate and replacement interval. Median and arithmetic mean were used. The results were expressed in graphs and tables. Results: The occupational index experienced a rising trend as it was the highest in 2018 with 66.9% affecting the services of neuropediatrics (88.1) and general pediatrics (78). Hospital stay showed a significant increase in 2018 although it did not exceed 4 days or in the services that treated these patients, which could correspond to difficulties in active case surveillance. The turnover rate and replacement interval were consistent with the occupational index, hospital stay and type of hospital. Conclusions: Changes in hospital indicators related to the efficient use of the bed resource were noticed, being more evident in 2018, a period in which dengue cases were reported in the province.

18.
Zootaxa ; 4619(3): zootaxa.4619.3.1, 2019 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-31716287

RESUMEN

Diplobodes africanus Mahunka, 1987, is redescribed by using Scanning Electron Microscopy (SEM) in order to complement optical microscopy. Diplobodes thailande sp. nov. from Thailand is described. For both species we include inclined views, to permit detailed analysis of ventral regions and to aid understanding of the complex relationships between elevated and depressed zones. Diplobodes thailande sp. nov. presents previously undescribed structures on legs III, which are involved in the leg folding process. Rwandabodes kayoveae gen. nov., sp. nov. presents a series of particular characteristics, such as: elevated interlamellar process on prodorsum, composed of a triangular structure, externally delimited by a low lamellar furrow; in setae inserted on elevated interlamellar process; large free lamellar tip; notogaster lacking ridges; anterior genital furrow extends into an oblique lateral depression; depressed area anterior to anal zone; both zones clearly delimited. These characteristics permit easy differentiation from related genera.


Asunto(s)
Ácaros , Animales , Microscopía , Rwanda , Tailandia
20.
Science ; 364(6438)2019 04 26.
Artículo en Inglés | MEDLINE | ID: mdl-31023897

RESUMEN

The practice of rewilding has been both promoted and criticized in recent years. Benefits include flexibility to react to environmental change and the promotion of opportunities for society to reconnect with nature. Criticisms include the lack of a clear conceptualization of rewilding, insufficient knowledge about possible outcomes, and the perception that rewilding excludes people from landscapes. Here, we present a framework for rewilding that addresses these concerns. We suggest that rewilding efforts should target trophic complexity, natural disturbances, and dispersal as interacting processes that can improve ecosystem resilience and maintain biodiversity. We propose a structured approach to rewilding projects that includes assessment of the contributions of nature to people and the social-ecological constraints on restoration.


Asunto(s)
Restauración y Remediación Ambiental , Vida Silvestre , Animales
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