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1.
J Anim Ecol ; 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38979934

RESUMO

Understanding patterns of species diversity is crucial for ecological research and conservation, and this understanding may be improved by studying patterns in the two components of species diversity, species richness and evenness of abundance of species. Variation in species richness and evenness has previously been linked to variation in total abundance of communities as well as productivity gradients. Exploring both components of species diversity is essential because these components could be unrelated or driven by different mechanisms. The aim of this study was to investigate the relationship between species richness and evenness in European bird communities along an extensive latitudinal gradient. We examined their relationships with latitude and Net Primary Productivity, which determines energy and matter availability for heterotrophs, as well as their responses to territory densities (i.e. the number of territories per area) and community biomass (i.e. the bird biomass per area). We applied a multivariate Poisson log-normal distribution to unique long-term, high-quality time-series data, allowing us to estimate species richness of the community as well as the variance of this distribution, which acts as an inverse measure of evenness. Evenness in the distribution of abundance of species in the community was independent of species richness. Species richness increased with increasing community biomass, as well as with increasing density. Since both measures of abundance were explained by NPP, species richness was partially explained by energy-diversity theory (i.e. the more energy, the more species sustained by the ecosystem). However, species richness did not increase linearly with NPP but rather showed a unimodal relationship. Evenness was not explained either by productivity nor by any of the aspects of community abundance. This study highlights the importance of considering both richness and evenness to gain a better understanding of variation in species diversity. We encourage the study of both components of species diversity in future studies, as well as use of simulation studies to verify observed patterns between richness and evenness.

2.
J Hand Surg Am ; 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38775759

RESUMO

Caring for hand and wrist injuries in the elite athlete brings distinct challenges, with case-by-case decisions regarding surgical intervention and return-to-play. Metacarpal fractures, thumb ulnar collateral ligament tears, and scaphoid fractures are common upper-extremity injuries in the elite athlete that can be detrimental to playing time and future participation. Treatment should therefore endure the demand of accelerated rehabilitation and return-to-activity without compromising long-term outcomes. Fortunately, the literature has supported emerging management options that support goals specific to the athlete. This review examined the advances in surgical and perioperative treatment of metacarpal fractures, thumb ulnar collateral ligament injuries, and scaphoid fractures in the elite athlete.

3.
Int J Cancer ; 155(5): 883-893, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38685816

RESUMO

Pembrolizumab has received approval in the UK as first-line monotherapy for recurrent and/or metastatic HNSCC (R/M HNSCC) following the results of the KEYNOTE-048 trial, which demonstrated a longer overall survival (OS) in comparison to the EXTREME chemotherapy regimen in patients with a combined positive score (CPS) ≥1. In this article, we provide retrospective real-world data on the role of pembrolizumab monotherapy as first-line systemic therapy for HNSCC across 18 centers in the UK from March 20, 2020 to May 31, 2021. 211 patients were included, and in the efficacy analysis, the objective response rate (ORR) was 24.7%, the median progression-free survival (PFS) was 4.8 months (95% confidence interval [CI]: 3.6-6.1), and the median OS was 10.8 months (95% CI 9.0-12.5). Pembrolizumab monotherapy was well tolerated, with 18 patients having to stop treatment owing to immune-related adverse events (irAEs). 53 patients proceeded to second-line treatment with a median PFS2 of 10.2 months (95% CI: 8.8-11.5). Moreover, patients with documented irAEs had a statistically significant longer median PFS (11.3 vs. 3.3 months; log-rank p value = <.001) and median OS (18.8 vs. 8.9 months; log-rank p value <.001). The efficacy and safety of pembrolizumab first-line monotherapy for HNSCC has been validated using real-world data.


Assuntos
Anticorpos Monoclonais Humanizados , Neoplasias de Cabeça e Pescoço , Carcinoma de Células Escamosas de Cabeça e Pescoço , Humanos , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais Humanizados/efeitos adversos , Masculino , Feminino , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Carcinoma de Células Escamosas de Cabeça e Pescoço/mortalidade , Pessoa de Meia-Idade , Idoso , Estudos Retrospectivos , Reino Unido/epidemiologia , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/mortalidade , Adulto , Idoso de 80 Anos ou mais , Antineoplásicos Imunológicos/uso terapêutico , Antineoplásicos Imunológicos/efeitos adversos , Intervalo Livre de Progressão
4.
Foot Ankle Spec ; : 19386400231218337, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38130108

RESUMO

BACKGROUND: First metatarsophalangeal (MTP) arthrodesis is a common surgical procedure for addressing hallux MTP pathology. In the setting of revision procedures with significant bone loss, porous titanium wedges may provide an alternative to structural bone autograft or allograft. OBJECTIVE: The purpose of this study is to report the clinical and radiographic outcomes achieved in first MTP interposition arthrodesis using porous titanium wedges. METHODS: A retrospective analysis of 9 patients with a mean age 65.4 years (45-82 years) who underwent first MTP interposition arthrodesis with the use of porous titanium wedges from February 2014 to September 2017 was performed. Outcomes were assessed using both plain-film radiographs and computed tomography (CT) scans, as well as patient-reported outcome measures, including Foot and Ankle Ability Measure (FAAM) (Sports and Activities of Daily Living), pain Visual Analogue Scale (VAS), and 36-Item Short Form Survey (SF-36). Average follow-up time was 34.2 months (14-72 months). RESULTS: At final follow-up, the average FAAM score was 91.1 ± 14.7 (75.1 ± 5.3 FAAM Activities of Daily Living; 17.9 ± 9.9 FAAM Sports). Average pain VAS score was 1.9 ± 1.7. Postoperative computed tomography (CT) imaging was obtained for 5 patients, all of which demonstrated good bony apposition or osseous integration of the wedge. Four patients underwent subsequent surgical procedures, including 3 isolated dorsal fixation revisions, and 1 complete MTP arthrodesis revision. CONCLUSION: To our knowledge, this study represents the first reported clinical and radiographic outcomes in patients undergoing first MTP interposition arthrodesis with use of porous titanium wedges. While we found this technique to be a viable alternative to bone grafting for this difficult problem, further research should focus on comparative data with other commonly performed operative techniques. LEVEL OF EVIDENCE: Level IV: Case series.

5.
ACS Energy Lett ; 8(10): 4421-4426, 2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37854051

RESUMO

In addition to their lifecycle carbon emissions, another important issue with decarbonized energy pathways is their air quality, water, or land use implications. This paper considers the air quality issue for ammonia combustion. When directly combusting ammonia, reactions of its N atom with atmospheric oxygen lead to NOx emissions that are O(103) ppm, 2 orders of magnitude higher than EPA limits or the amount emitted by current natural-gas-fired technologies. In order to provide guidance to policymakers and technologists on what is fundamentally possible, this Perspective analyzes the fundamental minimum NOx emissions that can be produced from ammonia combustion. The analysis shows that it is possible to achieve quite low NOx emission levels of O(10) ppm, but these designs differ markedly from those used in today's lean, premixed combustion systems.

6.
Nat Commun ; 14(1): 4304, 2023 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-37474503

RESUMO

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.


Assuntos
Aves , Mudança Climática , Animais , Ecossistema
7.
Nat Struct Mol Biol ; 30(6): 740-752, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37231154

RESUMO

Numerous proteins regulate gene expression by modulating mRNA translation and decay. To uncover the full scope of these post-transcriptional regulators, we conducted an unbiased survey that quantifies regulatory activity across the budding yeast proteome and delineates the protein domains responsible for these effects. Our approach couples a tethered function assay with quantitative single-cell fluorescence measurements to analyze ~50,000 protein fragments and determine their effects on a tethered mRNA. We characterize hundreds of strong regulators, which are enriched for canonical and unconventional mRNA-binding proteins. Regulatory activity typically maps outside the RNA-binding domains themselves, highlighting a modular architecture that separates mRNA targeting from post-transcriptional regulation. Activity often aligns with intrinsically disordered regions that can interact with other proteins, even in core mRNA translation and degradation factors. Our results thus reveal networks of interacting proteins that control mRNA fate and illuminate the molecular basis for post-transcriptional gene regulation.


Assuntos
Regulação da Expressão Gênica , Proteoma , RNA Mensageiro , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/análise , Proteínas de Saccharomyces cerevisiae/metabolismo , RNA Mensageiro/química , RNA Mensageiro/metabolismo , Processamento Pós-Transcricional do RNA , Estabilidade de RNA , Proteínas de Ligação a RNA/análise , Proteínas de Ligação a RNA/metabolismo
8.
Proc Natl Acad Sci U S A ; 120(21): e2216573120, 2023 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-37186854

RESUMO

Declines in European bird populations are reported for decades but the direct effect of major anthropogenic pressures on such declines remains unquantified. Causal relationships between pressures and bird population responses are difficult to identify as pressures interact at different spatial scales and responses vary among species. Here, we uncover direct relationships between population time-series of 170 common bird species, monitored at more than 20,000 sites in 28 European countries, over 37 y, and four widespread anthropogenic pressures: agricultural intensification, change in forest cover, urbanisation and temperature change over the last decades. We quantify the influence of each pressure on population time-series and its importance relative to other pressures, and we identify traits of most affected species. We find that agricultural intensification, in particular pesticides and fertiliser use, is the main pressure for most bird population declines, especially for invertebrate feeders. Responses to changes in forest cover, urbanisation and temperature are more species-specific. Specifically, forest cover is associated with a positive effect and growing urbanisation with a negative effect on population dynamics, while temperature change has an effect on the dynamics of a large number of bird populations, the magnitude and direction of which depend on species' thermal preferences. Our results not only confirm the pervasive and strong effects of anthropogenic pressures on common breeding birds, but quantify the relative strength of these effects stressing the urgent need for transformative changes in the way of inhabiting the world in European countries, if bird populations shall have a chance of recovering.


Assuntos
Agricultura , Florestas , Animais , Fazendas , Europa (Continente) , Dinâmica Populacional , Aves/fisiologia , Biodiversidade , Ecossistema , Conservação dos Recursos Naturais
9.
Philos Trans R Soc Lond B Biol Sci ; 378(1881): 20220198, 2023 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-37246375

RESUMO

Detecting biodiversity change and identifying its causes is challenging because biodiversity is multifaceted and temporal data often contain bias. Here, we model temporal change in species' abundance and biomass by using extensive data describing the population sizes and trends of native breeding birds in the United Kingdom (UK) and the European Union (EU). In addition, we explore how species' population trends vary with species' traits. We demonstrate significant change in the bird assemblages of the UK and EU, with substantial reductions in overall bird abundance and losses concentrated in a relatively small number of abundant and smaller sized species. By contrast, rarer and larger birds had generally fared better. Simultaneously, overall avian biomass had increased very slightly in the UK and was stable in the EU, indicating a change in community structure. Abundance trends across species were positively correlated with species' body mass and with trends in climate suitability, and varied with species' abundance, migration strategy and niche associations linked to diet. Our work highlights how changes in biodiversity cannot be captured easily by a single number; care is required when measuring and interpreting biodiversity change given that different metrics can provide very different insights. This article is part of the theme issue 'Detecting and attributing the causes of biodiversity change: needs, gaps and solutions'.


Assuntos
Biodiversidade , Mudança Climática , Animais , Biomassa , Reino Unido , Aves , Ecossistema
10.
Radiother Oncol ; 183: 109593, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36870609

RESUMO

BACKGROUND AND PURPOSE: This study aims to build machine learning models to predict radiation-induced rectal toxicities for three clinical endpoints and explore whether the inclusion of radiomic features calculated on radiotherapy planning computerised tomography (CT) scans combined with dosimetric features can enhance the prediction performance. MATERIALS AND METHODS: 183 patients recruited to the VoxTox study (UK-CRN-ID-13716) were included. Toxicity scores were prospectively collected after 2 years with grade ≥ 1 proctitis, haemorrhage (CTCAEv4.03); and gastrointestinal (GI) toxicity (RTOG) recorded as the endpoints of interest. The rectal wall on each slice was divided into 4 regions according to the centroid, and all slices were divided into 4 sections to calculate region-level radiomic and dosimetric features. The patients were split into a training set (75%, N = 137) and a test set (25%, N = 46). Highly correlated features were removed using four feature selection methods. Individual radiomic or dosimetric or combined (radiomic + dosimetric) features were subsequently classified using three machine learning classifiers to explore their association with these radiation-induced rectal toxicities. RESULTS: The test set area under the curve (AUC) values were 0.549, 0.741 and 0.669 for proctitis, haemorrhage and GI toxicity prediction using radiomic combined with dosimetric features. The AUC value reached 0.747 for the ensembled radiomic-dosimetric model for haemorrhage. CONCLUSIONS: Our preliminary results show that region-level pre-treatment planning CT radiomic features have the potential to predict radiation-induced rectal toxicities for prostate cancer. Moreover, when combined with region-level dosimetric features and using ensemble learning, the model prediction performance slightly improved.


Assuntos
Gastroenteropatias , Proctite , Neoplasias da Próstata , Lesões por Radiação , Masculino , Humanos , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/radioterapia , Reto/diagnóstico por imagem , Radiometria/métodos , Proctite/diagnóstico por imagem , Proctite/etiologia , Lesões por Radiação/diagnóstico por imagem , Lesões por Radiação/etiologia , Aprendizado de Máquina
11.
Acta Oncol ; 62(2): 166-173, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36802351

RESUMO

BACKGROUND: The irradiation of sub-regions of the parotid has been linked to xerostomia development in patients with head and neck cancer (HNC). In this study, we compared the xerostomia classification performance of radiomics features calculated on clinically relevant and de novo sub-regions of the parotid glands of HNC patients. MATERIAL AND METHODS: All patients (N = 117) were treated with TomoTherapy in 30-35 fractions of 2-2.167 Gy per fraction with daily mega-voltage-CT (MVCT) acquisition for image-guidance purposes. Radiomics features (N = 123) were extracted from daily MVCTs for the whole parotid gland and nine sub-regions. The changes in feature values after each complete week of treatment were considered as predictors of xerostomia (CTCAEv4.03, grade ≥ 2) at 6 and 12 months. Combinations of predictors were generated following the removal of statistically redundant information and stepwise selection. The classification performance of the logistic regression models was evaluated on train and test sets of patients using the Area Under the Curve (AUC) associated with the different sub-regions at each week of treatment and benchmarked with the performance of models solely using dose and toxicity at baseline. RESULTS: In this study, radiomics-based models predicted xerostomia better than standard clinical predictors. Models combining dose to the parotid and xerostomia scores at baseline yielded an AUCtest of 0.63 and 0.61 for xerostomia prediction at 6 and 12 months after radiotherapy while models based on radiomics features extracted from the whole parotid yielded a maximum AUCtest of 0.67 and 0.75, respectively. Overall, across sub-regions, maximum AUCtest was 0.76 and 0.80 for xerostomia prediction at 6 and 12 months. Within the first two weeks of treatment, the cranial part of the parotid systematically yielded the highest AUCtest. CONCLUSION: Our results indicate that variations of radiomics features calculated on sub-regions of the parotid glands can lead to earlier and improved prediction of xerostomia in HNC patients.


Assuntos
Neoplasias de Cabeça e Pescoço , Glândula Parótida , Xerostomia , Neoplasias de Cabeça e Pescoço/radioterapia , Xerostomia/complicações , Humanos , Radiômica , Glândula Parótida/diagnóstico por imagem , Glândula Parótida/efeitos da radiação , Dosagem Radioterapêutica , Processamento de Imagem Assistida por Computador , Masculino , Feminino , Pessoa de Meia-Idade , Idoso
12.
Phys Imaging Radiat Oncol ; 25: 100404, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36660107

RESUMO

Background and purpose: While core to the scientific approach, reproducibility of experimental results is challenging in radiomics studies. A recent publication identified radiomics features that are predictive of late irradiation-induced toxicity in head and neck cancer (HNC) patients. In this study, we assessed the generalisability of these findings. Materials and Methods: The procedure described in the publication in question was applied to a cohort of 109 HNC patients treated with 50-70 Gy in 20-35 fractions using helical radiotherapy although there were inherent differences between the two patient populations and methodologies. On each slice of the planning CT with delineated parotid and submandibular glands, the imaging features that were previously identified as predictive of moderate-to-severe xerostomia and sticky saliva 12 months post radiotherapy (Xer12m and SS12m) were calculated. Specifically, Short Run Emphasis (SRE) and maximum CT intensity (maxHU) were evaluated for improvement in prediction of Xer12m and SS12m respectively, compared to models solely using baseline toxicity and mean dose to the salivary glands. Results: None of the associations previously identified as statistically significant and involving radiomics features in univariate or multivariate models could be reproduced on our cohort. Conclusion: The discrepancies observed between the results of the two studies delineate limits to the generalisability of the previously reported findings. This may be explained by the differences in the approaches, in particular the imaging characteristics and subsequent methodological implementation. This highlights the importance of external validation, high quality reporting guidelines and standardisation protocols to ensure generalisability, replication and ultimately clinical implementation.

13.
Conserv Biol ; 37(1): e13967, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35694785

RESUMO

Although some sectors have made significant progress in learning from failure, there is currently limited consensus on how a similar transition could best be achieved in conservation and what is required to facilitate this. One of the key enabling conditions for other sectors is a widely accepted and standardized classification system for identifying and analyzing root causes of failure. We devised a comprehensive taxonomy of root causes of failure affecting conservation projects. To develop this, we solicited examples of real-life conservation efforts that were deemed to have failed in some way, identified their underlying root causes of failure, and used these to develop a generic, 3-tier taxonomy of the ways in which projects fail, at the top of which are 6 overarching cause categories that are further divided into midlevel cause categories and specific root causes. We tested the taxonomy by asking conservation practitioners to use it to classify the causes of failure for conservation efforts they had been involved in. No significant gaps or redundancies were identified during this testing phase. We then analyzed the frequency that particular root causes were encountered by projects within this test sample, which suggested that some root causes were more likely to be encountered than others and that a small number of root causes were more likely to be encountered by projects implementing particular types of conservation action. Our taxonomy could be used to improve identification, analysis, and subsequent learning from failed conservation efforts, address some of the barriers that currently limit the ability of conservation practitioners to learn from failure, and contribute to establishing an effective culture of learning from failure within conservation.


Introducción de una taxonomía común como apoyo al aprendizaje a partir del fracaso en la conservación Resumen Mientras que algunos sectores han progresado significativamente en el aprendizaje a partir del fracaso, actualmente hay un consenso limitado sobre cómo podría lograrse una transición similar en la conservación y qué se requiere para facilitarla. Una de las condiciones habilitantes más importantes en otros sectores es un sistema de clasificación estandarizado y aceptado por la mayoría para la identificación y análisis de las causas fundamentales del fracaso. Diseñamos una taxonomía completa de las causas fundamentales del fracaso que afecta a los proyectos de conservación. Para desarrollarla, solicitamos ejemplos de esfuerzos de conservación reales que de alguna manera se consideraron como fracasos, identificamos las causas fundamentales no aparentes de su fracaso y luego las usamos para desarrollar una taxonomía genérica de tres niveles de las maneras en las que fracasan los proyectos, en cuyo nivel superior están seis categorías de causas generales que después se dividen en categorías de nivel medio de categorías de causas y causas fundamentales específicas. Pusimos a prueba la taxonomía al pedirle a los practicantes de la conservación que la usaran para clasificar las causas del fracaso de los esfuerzos de conservación en los que han participado. No identificamos vacíos o redundancias importantes durante esta fase de prueba. Después, analizamos la frecuencia con la que los proyectos de esta muestra se enfrentaron a causas fundamentales particulares, lo que sugirió que algunas causas fundamentales tienen mayor probabilidad de ocurrir y que un número reducido de causas fundamentales tiene mayor probabilidad de ocurrir en proyectos que implementan ciertos tipos de acciones de conservación. Nuestra taxonomía podría usarse para mejorar el análisis, identificación y aprendizaje subsecuente a partir del fracaso de los esfuerzos de conservación; tratar algunas de las barreras que en la actualidad limitan a los practicantes de la conservación a aprender del fracaso; y contribuir al establecimiento de una cultura efectiva del aprendizaje a partir del fracaso dentro de la conservación.


Assuntos
Conservação dos Recursos Naturais , Terminologia como Assunto
14.
Phys Imaging Radiat Oncol ; 24: 95-101, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36386445

RESUMO

Background and purpose: The images acquired during radiotherapy for image-guidance purposes could be used to monitor patient-specific response to irradiation and improve treatment personalisation. We investigated whether the kinetics of radiomics features from daily mega-voltage CT image-guidance scans (MVCT) improve prediction of moderate-to-severe xerostomia compared to dose/volume parameters in radiotherapy of head-and-neck cancer (HNC). Materials and Methods: All included HNC patients (N = 117) received 30 or more fractions of radiotherapy with daily MVCTs. Radiomics features were calculated on the contra-lateral parotid glands of daily MVCTs. Their variations over time after each complete week of treatment were used to predict moderate-to-severe xerostomia (CTCAEv4.03 grade ≥ 2) at 6, 12 and 24 months post-radiotherapy. After dimensionality reduction, backward/forward selection was used to generate combinations of predictors.Three types of logistic regression model were generated for each follow-up time: 1) a pre-treatment reference model using dose/volume parameters, 2) a combination of dose/volume and radiomics-based predictors, and 3) radiomics-based predictors. The models were internally validated by cross-validation and bootstrapping and their performance evaluated using Area Under the Curve (AUC) on separate training and testing sets. Results: Moderate-to-severe xerostomia was reported by 46 %, 33 % and 26 % of the patients at 6, 12 and 24 months respectively. The selected models using radiomics-based features extracted at or before mid-treatment outperformed the dose-based models with an AUCtrain/AUCtest of 0.70/0.69, 0.76/0.74, 0.86/0.86 at 6, 12 and 24 months, respectively. Conclusion: Our results suggest that radiomics features calculated on MVCTs from the first half of the radiotherapy course improve prediction of moderate-to-severe xerostomia in HNC patients compared to a dose-based pre-treatment model.

15.
Environ Pollut ; 314: 120269, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36162558

RESUMO

Second generation anticoagulant rodenticides (SGARs) are widely used to control rodents around the world. However, contamination by SGARs is detectable in many non-target species, particularly carnivorous mammals or birds-of-prey that hunt or scavenge on poisoned rodents. The SGAR trophic transfer pathway via rodents and their predators/scavengers appears widespread, but little is known of other pathways of SGAR contamination in non-target wildlife. This is despite the detection of SGARs in predators that do not eat rodents, such as specialist bird-eating hawks. We used a Bayesian modelling framework to examine the extent and spatio-temporal trends of SGAR contamination in the livers of 259 Eurasian Sparrowhawks, a specialist bird-eating raptor, in regions of Britain during 1995-2015. SGARs, predominantly difenacoum, were detected in 81% of birds, with highest concentrations in males and adults. SGAR concentrations in birds were lowest in Scotland and higher or increasing in other regions of Britain, which had a greater arable or urban land cover where SGARs may be widely deployed for rodent control. However, there was no overall trend for Britain, and 97% of SGAR residues in Eurasian Sparrowhawks were below 100 ng/g (wet weight), which is a potential threshold for lethal effects. The results have potential implications for the population decline of Eurasian Sparrowhawks in Britain. Fundamentally, the results indicate an extensive and persistent contamination of the avian trophic transfer pathway on a national scale, where bird-eating raptors and, by extension, their prey appear to be widely exposed to SGARs. Consequently, these findings have implications for wildlife contamination worldwide, wherever these common rodenticides are deployed, as widespread exposure of non-target species can apparently occur via multiple trophic transfer pathways involving birds as well as rodents.


Assuntos
Águias , Falcões , Aves Predatórias , Rodenticidas , Masculino , Animais , Rodenticidas/metabolismo , Falcões/metabolismo , Anticoagulantes/metabolismo , Reino Unido , Teorema de Bayes , Monitoramento Ambiental , Aves Predatórias/metabolismo , Águias/metabolismo , Animais Selvagens/metabolismo , Mamíferos/metabolismo
16.
Ecology ; 103(8): e3731, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35416286

RESUMO

Our knowledge of the factors affecting species abundances is mainly based on time-series analyses of a few well-studied species at single or few localities, but we know little about whether results from such analyses can be extrapolated to the community level. We apply a joint species distribution model to long-term time-series data on British bird communities to examine the relative contribution of intra- and interspecific density dependence at different spatial scales, as well as the influence of environmental stochasticity, to spatiotemporal interspecific variation in abundance. Intraspecific density dependence has the major structuring effect on these bird communities. In addition, environmental fluctuations affect spatiotemporal differences in abundance. In contrast, species interactions had a minor impact on variation in abundance. Thus, important drivers of single-species dynamics are also strongly affecting dynamics of communities in time and space.


Assuntos
Aves , Ecossistema , Animais , Dinâmica Populacional
19.
Br J Radiol ; 95(1133): 20211175, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35220723

RESUMO

OBJECTIVES: High-energy Proton Beam Therapy (PBT) commenced in England in 2018 and NHS England commissions PBT for 1.5% of patients receiving radical radiotherapy. We sought expert opinion on the level of provision. METHODS: Invitations were sent to 41 colleagues working in PBT, most at one UK centre, to contribute by completing a spreadsheet. 39 responded: 23 (59%) completed the spreadsheet; 16 (41%) declined, arguing that clinical outcome data are lacking, but joined six additional site-specialist oncologists for two consensus meetings. The spreadsheet was pre-populated with incidence data from Cancer Research UK and radiotherapy use data from the National Cancer Registration and Analysis Service. 'Mechanisms of Benefit' of reduced growth impairment, reduced toxicity, dose escalation and reduced second cancer risk were examined. RESULTS: The most reliable figure for percentage of radical radiotherapy patients likely to benefit from PBT was that agreed by 95% of the 23 respondents at 4.3%, slightly larger than current provision. The median was 15% (range 4-92%) and consensus median 13%. The biggest estimated potential benefit was from reducing toxicity, median benefit to 15% (range 4-92%), followed by dose escalation median 3% (range 0 to 47%); consensus values were 12 and 3%. Reduced growth impairment and reduced second cancer risk were calculated to benefit 0.5% and 0.1%. CONCLUSIONS: The most secure estimate of percentage benefit was 4.3% but insufficient clinical outcome data exist for confident estimates. The study supports the NHS approach of using the evidence base and developing it through randomised trials, non-randomised studies and outcomes tracking. ADVANCES IN KNOWLEDGE: Less is known about the percentage of patients who may benefit from PBT than is generally acknowledged. Expert opinion varies widely. Insufficient clinical outcome data exist to provide robust estimates. Considerable further work is needed to address this, including international collaboration; much is already underway but will take time to provide mature data.


Assuntos
Segunda Neoplasia Primária , Terapia com Prótons , Terapia por Raios X , Humanos , Segunda Neoplasia Primária/radioterapia
20.
J Am Acad Orthop Surg ; 29(24): e1321-e1327, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34874335

RESUMO

INTRODUCTION: The coronavirus disease 2019 (COVID-19) pandemic resulted in the unprecedented widespread cancellation of scheduled elective primary total joint arthroplasty (TJA) in the United States. The impact of postponing scheduled total hip arthroplasty and total knee arthroplasty procedures on patients has not been well studied and may have physical, emotional, and financial consequences. METHODS: All patients whose elective primary TJA procedures at a tertiary academic medical center were postponed because of COVID-19 were surveyed. Seventy-four patients agreed to answer 13 questions concerning the physical, mental, and financial impact of surgery cancellation. Statistical analysis, including Pearson correlation coefficients, cross-tabulation analysis, and chi squares, was performed. RESULTS: 13.5% of patients strongly disagreed with the use of "elective" to describe their cancelled TJA surgery and 25.7% of patients reported substantial physical and/or mental deterioration due to postponement. Younger individuals experienced greater change in their symptoms (P = 0.034), anxiety about their pain (P = 0.010), and frustration/anger (P = 0.043). Poor quality of life, mood, and lower HOOS/KOOS Jr interval scores were correlated with greater financial strain, disagreement with the postponement, and disagreement with the use of "elective" to describe surgery. Disagreement with the use of "elective" to describe surgery was associated with greater financial strain (P = 0.013) and disagreement with the decision to postpone surgery (P = 0.008). In addition, greater financial strain was associated with disagreement with postponement (P = 0.014). CONCLUSION: The cancellation of elective TJA during the COVID-19 pandemic had a variety of consequences for patients. One in four patients reported experiencing substantial physical and/or emotional deterioration. Associations of poor quality of life and mood with greater financial strain and disagreement with the term "elective" were seen. These results help quantify the deleterious effects of cancelling elective surgery and identify at-risk patients should another postponement of surgery occur. LEVEL OF EVIDENCE: Level II-Prospective cohort study.


Assuntos
Artroplastia de Quadril , Artroplastia do Joelho , COVID-19 , Artroplastia de Quadril/efeitos adversos , Artroplastia do Joelho/efeitos adversos , Procedimentos Cirúrgicos Eletivos , Humanos , Pandemias , Estudos Prospectivos , Qualidade de Vida , SARS-CoV-2 , Estados Unidos/epidemiologia
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