32 research outputs found
Biological invasions are a population-level rather than a species-level phenomenon
Biological invasions pose a rapidly expanding threat to the persistence, functioning and service provisioning of ecosystems globally, and to socio-economic interests. The stages of successful invasions are driven by the same mechanism that underlies adaptive changes across species in general—via natural selection on intraspecific variation in traits that influence survival and reproductive performance (i.e., fitness). Surprisingly, however, the rapid progress in the field of invasion science has resulted in a predominance of species-level approaches (such as deny lists), often irrespective of natural selection theory, local adaptation and other population-level processes that govern successful invasions. To address these issues, we analyse non-native species dynamics at the population level by employing a database of European freshwater macroinvertebrate time series, to investigate spreading speed, abundance dynamics and impact assessments among populations. Our findings reveal substantial variability in spreading speed and abundance trends within and between macroinvertebrate species across biogeographic regions, indicating that levels of invasiveness and impact differ markedly. Discrepancies and inconsistencies among species-level risk screenings and real population-level data were also identified, highlighting the inherent challenges in accurately assessing population-level effects through species-level assessments. In recognition of the importance of population-level assessments, we urge a shift in invasive species management frameworks, which should account for the dynamics of different populations and their environmental context. Adopting an adaptive, region-specific and population-focused approach is imperative, considering the diverse ecological contexts and varying degrees of susceptibility. Such an approach could improve and refine risk assessments while promoting mechanistic understandings of risks and impacts, thereby enabling the development of more effective conservation and management strategies
New aspects in the biology of fish pathogen Photobacterium damselae subsp. piscicida: pili, motility and adherence to solid surfaces
Phenotypic differentiation among native, expansive and introduced populations influences invasion success
Aim: Humans influence species distributions by modifying the environment and by dispersing species beyond their natural ranges. Populations of species that have established in disjunct regions of the world may exhibit trait differentiation from native populations due to founder effects and adaptations to selection pressures in each distributional region. We compared multiple native, expansive and introduced populations of a single species across the world, considering the influence of environmental stressors and transgenerational effects. Location: United States Gulf and Atlantic coasts, United States interior, European Atlantic and Mediterranean coasts, east coast of Australia. Taxon: Baccharis halimifolia L. (eastern baccharis). Methods: We monitored seed germination, seedling emergence, survival and early growth in a common garden experiment, conducted with over 18,200 seeds from 80 populations. We also evaluated the influence of environmental stress and maternal traits on progeny performance. Results: Introduced European Atlantic populations had faster germination and early growth than native populations. However, this was not the case for the more recently naturalized European Mediterranean populations. Introduced Australian populations grew faster than native populations in non-saline environments but had lower survival in saline conditions commonly encountered in the native range. Similarly, expansive inland US populations germinated faster than coastal native populations in non-saline environments but grew and germinated more slowly in saline environments. Maternal inflorescence and plant size were positively related with seed germination and seedling survival, whereas flower abundance was positively correlated with seedling early growth and survival. However, maternal traits explained a much lower fraction of the total variation in early demographic stages of B. halimifolia than did distributional range. Main conclusions: Phenotypic differentiation could allow B. halimifolia to adapt to different biotic and abiotic selection pressures found in each distributional range, potentially contributing to its success in introduced and expansive ranges
Obstetric complications and clinical presentation in first episode of psychosis
Objective: Psychotic disorders exhibit a complex aetiology that combines genetic and environmental factors. Among the latter, obstetric complications (OCs) have been widely studied as risk factors, but it is not yet well understood how OCs relate to the heterogeneous presentations of psychotic disorders. We assessed the clinical phenotypes of individuals with a first episode of psychosis (FEP) in relation to the presence of OCs. Methods: Two-hundred seventy-seven patients with an FEP were assessed for OCs using the Lewis–Murray scale, with data stratified into three subscales depending on the timing and the characteristics of the obstetric event, namely: complications of pregnancy, abnormal foetal growth and development and difficulties in delivery. We also considered other two groups: any complications during the pregnancy period and all OCs taken altogether. Patients were clinically evaluated with the Positive and Negative Syndrome Scale for schizophrenia. Results: Total OCs and difficulties in delivery were related to more severe psychopathology, and this remained significant after co-varying for age, sex, traumatic experiences, antipsychotic dosage and cannabis use. Conclusions: Our results highlight the relevance of OCs for the clinical presentation of psychosis. Describing the timing of the OCs is essential in understanding the heterogeneity of the clinical presentation
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Does urbanisation lead to parallel demographic shifts across the world in a cosmopolitan plant?
Urbanisation is occurring globally, leading to dramatic environmental changes that are altering the ecology and evolution of species. In particular, the expansion of human infrastructure and the loss and fragmentation of natural habitats in cities is predicted to increase genetic drift and reduce gene flow by reducing the size and connectivity of populations. Alternatively, the ‘urban facilitation model’ suggests that some species will have greater gene flow into and within cities leading to higher diversity and lower differentiation in urban populations. These alternative hypotheses have not been contrasted across multiple cities. Here, we used the genomic data from the GLobal Urban Evolution project (GLUE), to study the effects of urbanisation on non‐adaptive evolutionary processes of white clover (Trifolium repens) at a global scale. We found that white clover populations presented high genetic diversity and no evidence of reduced Ne linked to urbanisation. On the contrary, we found that urban populations were less likely to experience a recent decrease in effective population size than rural ones. In addition, we found little genetic structure among populations both globally and between urban and rural populations, which showed extensive gene flow between habitats. Interestingly, white clover displayed overall higher gene flow within urban areas than within rural habitats. Our study provides the largest comprehensive test of the demographic effects of urbanisation. Our results contrast with the common perception that heavily altered and fragmented urban environments will reduce the effective population size and genetic diversity of populations and contribute to their isolation
Biological invasions are a population-level rather than a species-level phenomenon.
Biological invasions pose a rapidly expanding threat to the persistence, functioning and service provisioning of ecosystems globally, and to socio-economic interests. The stages of successful invasions are driven by the same mechanism that underlies adaptive changes across species in general-via natural selection on intraspecific variation in traits that influence survival and reproductive performance (i.e., fitness). Surprisingly, however, the rapid progress in the field of invasion science has resulted in a predominance of species-level approaches (such as deny lists), often irrespective of natural selection theory, local adaptation and other population-level processes that govern successful invasions. To address these issues, we analyse non-native species dynamics at the population level by employing a database of European freshwater macroinvertebrate time series, to investigate spreading speed, abundance dynamics and impact assessments among populations. Our findings reveal substantial variability in spreading speed and abundance trends within and between macroinvertebrate species across biogeographic regions, indicating that levels of invasiveness and impact differ markedly. Discrepancies and inconsistencies among species-level risk screenings and real population-level data were also identified, highlighting the inherent challenges in accurately assessing population-level effects through species-level assessments. In recognition of the importance of population-level assessments, we urge a shift in invasive species management frameworks, which should account for the dynamics of different populations and their environmental context. Adopting an adaptive, region-specific and population-focused approach is imperative, considering the diverse ecological contexts and varying degrees of susceptibility. Such an approach could improve and refine risk assessments while promoting mechanistic understandings of risks and impacts, thereby enabling the development of more effective conservation and management strategies
A922 Sequential measurement of 1 hour creatinine clearance (1-CRCL) in critically ill patients at risk of acute kidney injury (AKI)
Meeting abstrac
Global urban environmental change drives adaptation in white clover.
Urbanization transforms environments in ways that alter biological evolution. We examined whether urban environmental change drives parallel evolution by sampling 110,019 white clover plants from 6169 populations in 160 cities globally. Plants were assayed for a Mendelian antiherbivore defense that also affects tolerance to abiotic stressors. Urban-rural gradients were associated with the evolution of clines in defense in 47% of cities throughout the world. Variation in the strength of clines was explained by environmental changes in drought stress and vegetation cover that varied among cities. Sequencing 2074 genomes from 26 cities revealed that the evolution of urban-rural clines was best explained by adaptive evolution, but the degree of parallel adaptation varied among cities. Our results demonstrate that urbanization leads to adaptation at a global scale
Identification of potential invasive alien species in Spain through horizon scanning
Invasive alien species have widespread impacts on native biodiversity and ecosystem services. Since the number of introductions worldwide is continuously rising, it is essential to prevent the entry, establishment and spread of new alien species through a systematic examination of future potential threats. Applying a three-step horizon scanning consensus method, we evaluated non-established alien species that could potentially arrive, establish and cause major ecological impact in Spain within the next 10 years. Overall, we identified 47 species with a very high risk (e.g. Oreochromis niloticus, Popillia japonica, Hemidactylus frenatus, Crassula helmsii or Halophila stipulacea), 61 with high risk, 93 with moderate risk, and 732 species with low risk. Many of the species categorized as very high or high risk to Spanish biodiversity are either already present in Europe and neighbouring countries or have a long invasive history elsewhere. This study provides an updated list of potential invasive alien species useful for prioritizing efforts and resources against their introduction. Compared to previous horizon scanning exercises in Spain, the current study screens potential invaders from a wider range of terrestrial, freshwater, and marine organisms, and can serve as a basis for more comprehensive risk analyses to improve management and increase the efficiency of the early warning and rapid response framework for invasive alien species. We also stress the usefulness of measuring agreement and consistency as two different properties of the reliability of expert scores, in order to more easily elaborate consensus ranked lists of potential invasive alien species.This work is one of the main results of the InvaNET network (RED2018-102571-T, RED2022-134338-T, https://invasiber.org/InvaNET/), financially supported by MCIN/AEI/10.13039/501100011033. We thank Guido Jones, funded by the Cabildo de Tenerife under the TFinnova Programme supported by MEDI and FDCAN, for revising the English.Peer reviewe
Nutrición parenteral domiciliaria en España 2018. Informe del Grupo de Nutrición Artificial Domiciliaria y Ambulatoria NADYA
Objetivo: comunicar los datos de nutrición parenteral domiciliaria (NPD) obtenidos del registro del grupo NADYA-SENPE (www.nadya-senpe.com) del año 2018.
Material y métodos: análisis descriptivo de los datos recogidos de pacientes adultos y pediátricos con NPD en el registro NADYA-SENPE del 1 de enero al 31 de diciembre de 2018.
Resultados: se registraron 278 pacientes (54, 7% mujeres), 23 niños y 255 adultos, procedentes de 45 hospitales españoles, lo que representa una tasa de prevalencia de 5, 95 pacientes/millón de habitantes/año 2018. El diagnóstico más frecuente en adultos fue “oncológico paliativo” (22, 0%), seguido de “otros”. En niños fue la enfermedad de Hirschsprung junto con la enterocolitis necrotizante, con cuatro casos (17, 4%). El primer motivo de indicación fue síndrome de intestino corto tanto en niños (60, 9%) como en adultos (35, 7%). El tipo de catéter más utilizado fue el tunelizado tanto en niños (81, 0%) como en adultos (41, 1%). Finalizaron 75 episodios, la causa más frecuente fue el fallecimiento (52, 0%) y el paso a vía oral (33, 3%).
Conclusiones: el número de centros y profesionales colaboradores en el registro de pacientes que reciben NPD se mantiene estable, así como las principales indicaciones y los motivos de finalización de la NPD.
Aim: To communicate home parenteral nutrition (HPN) data obtained from the HPN registry of the NADYA-SENPE group (www.nadya-senpe. com) for the year 2018.
Material and methods: Descriptive analysis of the data collected from adult and pediatric patients with HPN in the NADYA-SENPE group registry from January 1st, 2018 to December 31st, 2018.
Results: There were 278 patients from 45 Spanish hospitals (54.7% women), 23 children and 255 adults, which represent a prevalence rate of 5.95 patients/million inhabitants/year 2018. The most frequent diagnosis in adults was “palliative cancer” (22.0%), followed by “others”. In children it was Hirschsprung’s disease together with necrotizing enterocolitis, with four cases (17.4%). The first indication was short bowel syndrome in both children (60.9%) and adults (35.7%). The most frequently used type of catheter was tunneled in both children (81.0%) and adults (41.1%). Ending 75 episodes, the most frequent cause was death (52.0%) and change to oral feeding (33.3%).
Conclusions: The number of centers and collaborating professionals in the registry of patients receiving HPN remains stable, as well as the main indications and reasons for termination of HPN