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The global retreat of glaciers is dramatically altering mountain and high-latitude landscapes, with new ecosystems developing from apparently barren substrates1-4. The study of these emerging ecosystems is critical to understanding how climate change interacts with microhabitat and biotic communities and determines the future of ice-free terrains1,5. Here, using a comprehensive characterization of ecosystems (soil properties, microclimate, productivity and biodiversity by environmental DNA metabarcoding6) across 46 proglacial landscapes worldwide, we found that all the environmental properties change with time since glaciers retreated, and that temperature modulates the accumulation of soil nutrients. The richness of bacteria, fungi, plants and animals increases with time since deglaciation, but their temporal patterns differ. Microorganisms colonized most rapidly in the first decades after glacier retreat, whereas most macroorganisms took longer. Increased habitat suitability, growing complexity of biotic interactions and temporal colonization all contribute to the increase in biodiversity over time. These processes also modify community composition for all the groups of organisms. Plant communities show positive links with all other biodiversity components and have a key role in ecosystem development. These unifying patterns provide new insights into the early dynamics of deglaciated terrains and highlight the need for integrated surveillance of their multiple environmental properties5.
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Biodiversidade , Ecossistema , Aquecimento Global , Camada de Gelo , Animais , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Fungos/classificação , Fungos/genética , Fungos/isolamento & purificação , Camada de Gelo/microbiologia , Plantas/microbiologia , Solo/química , Microbiologia do Solo , Temperatura , Fatores de Tempo , Código de Barras de DNA Taxonômico , MicroclimaRESUMO
The development of terrestrial ecosystems depends greatly on plant mutualists such as mycorrhizal fungi. The global retreat of glaciers exposes nutrient-poor substrates in extreme environments and provides a unique opportunity to study early successions of mycorrhizal fungi by assessing their dynamics and drivers. We combined environmental DNA metabarcoding and measurements of local conditions to assess the succession of mycorrhizal communities during soil development in 46 glacier forelands around the globe, testing whether dynamics and drivers differ between mycorrhizal types. Mycorrhizal fungi colonized deglaciated areas very quickly (< 10 yr), with arbuscular mycorrhizal fungi tending to become more diverse through time compared to ectomycorrhizal fungi. Both alpha- and beta-diversity of arbuscular mycorrhizal fungi were significantly related to time since glacier retreat and plant communities, while microclimate and primary productivity were more important for ectomycorrhizal fungi. The richness and composition of mycorrhizal communities were also significantly explained by soil chemistry, highlighting the importance of microhabitat for community dynamics. The acceleration of ice melt and the modifications of microclimate forecasted by climate change scenarios are expected to impact the diversity of mycorrhizal partners. These changes could alter the interactions underlying biotic colonization and belowground-aboveground linkages, with multifaceted impacts on soil development and associated ecological processes.
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Biodiversidade , Camada de Gelo , Micorrizas , Micorrizas/fisiologia , Camada de Gelo/microbiologia , Solo/química , Microclima , Microbiologia do SoloRESUMO
The worldwide retreat of glaciers is causing a faster than ever increase in ice-free areas that are leading to the emergence of new ecosystems. Understanding the dynamics of these environments is critical to predicting the consequences of climate change on mountains and at high latitudes. Climatic differences between regions of the world could modulate the emergence of biodiversity and functionality after glacier retreat, yet global tests of this hypothesis are lacking. Nematodes are the most abundant soil animals, with keystone roles in ecosystem functioning, but the lack of global-scale studies limits our understanding of how the taxonomic and functional diversity of nematodes changes during the colonization of proglacial landscapes. We used environmental DNA metabarcoding to characterize nematode communities of 48 glacier forelands from five continents. We assessed how different facets of biodiversity change with the age of deglaciated terrains and tested the hypothesis that colonization patterns are different across forelands with different climatic conditions. Nematodes colonized ice-free areas almost immediately. Both taxonomic and functional richness quickly increased over time, but the increase in nematode diversity was modulated by climate, so that colonization started earlier in forelands with mild summer temperatures. Colder forelands initially hosted poor communities, but the colonization rate then accelerated, eventually leveling biodiversity differences between climatic regimes in the long term. Immediately after glacier retreat, communities were dominated by colonizer taxa with short generation time and r-ecological strategy but community composition shifted through time, with increased frequency of more persister taxa with K-ecological strategy. These changes mostly occurred through the addition of new traits instead of their replacement during succession. The effects of local climate on nematode colonization led to heterogeneous but predictable patterns around the world that likely affect soil communities and overall ecosystem development.
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Ecossistema , Nematoides , Animais , Solo , Camada de Gelo , BiodiversidadeRESUMO
Kelp species function as important foundation organisms in coastal marine ecosystems where they provide biogenic habitat and ameliorate environmental conditions, often facilitating the development of diverse understorey assemblages. The structure of kelp forests is influenced by a variety of environmental factors, changes in which can result in profound shifts in ecological structure and functioning. Intense storm-induced wave action in particular, can severely impact kelp forest ecosystems. Given that storms are anticipated to increase in frequency and intensity in response to anthropogenic climate change, it is critical to understand their potential impacts on kelp forest ecosystems. During the 2021/22 northeast Atlantic storm season, the United Kingdom (UK) was subject to several intense storms, of which the first and most severe was Storm Arwen. Due to the unusual northerly wind direction, the greatest impacts of Storm Arwen were felt along the northeast coast of the UK where wind gusts exceeded 90 km/h, and inshore significant wave heights of 7.2 m and wave periods of 9.3 s were recorded. Here, we investigated temporal and spatial variation in the structure of L. hyperborea forests and associated understorey assemblages along the northeast coast of the UK over the 2021/22 storm season. We found significant changes in the cover, density, length, biomass, and age structure of L. hyperborea populations and the composition of understorey assemblages following the storm season, particularly at our most north facing site. We suggest continuous monitoring of these systems to further our understanding of temporal variation and potential recovery trajectories, alongside enhanced management to promote resilience to future perturbations.
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AIMS: The aim of this propensity score matched cohort study was to assess the outcomes of telehealth-guided outpatient management of acute heart failure (HF) in our virtual ward (HFVW) compared with hospitalized acute HF patients. METHODS AND RESULTS: This cohort study (May 2022-October 2023) assessed outcomes of telehealth-guided outpatient acute HF management using bolus intravenous furosemide in a HF-specialist VW. Propensity score matching (PSM) was performed using logistic regression to adjust for potential differences in baseline patient characteristics between HFVW and standard care [Get With The Guidelines-HF score, clinical frailty score (CFS), Charlson co-morbidity index (CCI), NT-proBNP, and ejection fraction]. Clinical outcomes (re-hospitalizations and mortality) were compared at 1, 3, 6, and 12 months versus standard care-SC (acute HF patients managed without telehealth in 2021). Five hundred fifty-four HFVW ADHF patients (age 73.1 ± 10.9 years; 46% female) were compared with 404 ADHF patients (74.2 ± 11.8; P = 0.15 and 49% female) in the standard care-SC cohort. After propensity score matching for baseline patient characteristics, re-hospitalizations were significantly lower in the HFVW compared with SC (1 month-HFVW 8.6% vs. SC-21.5%, P < 0.001; 3 months-21% vs. 30%, P = 0.003; 6 months-28% vs 41%, P < 0.001 and 12 months-47% vs. 57%, P = 0.005) and mortality was also lower at 1 month (5% vs. 13.7%; P < 0.001), 3 months (9.5% vs. 15%; P = 0.001), 6 months (15% vs. 21%; P = 0.03), and 12 months (20% vs. 26%; P = 0.04). Multivariate logistic regression analysis showed that compared with standard care, HFVW management was associated with lower odds of readmission (1-month odds ratio (OR) = 0.3 [95% Confidence Interval CI 0.2-0.5], P < 0.0001; 3 month OR = 0.15 [0.1-0.3], P < 0.0001; 6-month OR = 0.35 [0.2-0.6], P = 0.0002; 12-month OR = 0.25 [0.15-0.4], P ≤ 0.001 and mortality (1-month OR = 0.26 [0.14-0.48], P < 0.0001; 3-month OR = 0.11 [0.04-0.27], P < 0.0001; 6-month OR = 0.35, [0.2; 0.61], P = 0.0002; 12-month OR = 0.6 [0.48; 0.73], P = 0.03. Higher GWTG-HF score independently predicted increased odds of re-hospitalization (1-month OR = 1.2 [1.1-1.3], P < 0.001; 3-month OR = 1.5 [1.37; 1.64], P < 0.0001; 6-month OR = 1.3 [1.2-1.4], P < 0.0001; 12-month OR = 1.1 [1.05-1.2], P = 0.03) as well as mortality (1-month OR = 1.21 [1.1-1.3], P < 0.0001; 3-month OR = 1.3 [1.2-1.4], P < 0.0001; 6-month OR = 1.2 [1.1-1.3], P < 0.0001; 12-month OR = 1.3 [1.1-1.7], P = 0.02). Similarly higher CFS also independently predicted increased odds of re-hospitalizations (1-month OR = 1.9 [1.5-2.4], P < 0.0001; 3-month OR = 1.8 [1.3-2.4], P = 0.0003; 6-month OR = 1.4 [1.1-1.8], P = 0.015; 12-month OR 1.9 [1.2-3], P = 0.01]) and mortality (1-month OR = 2.1 [1.6-2.8], P < 0.0001; 3-month OR = 1.8 [1.2-2.6], P = 0.006; 6-month OR = 2.34 [1.51-5.6], P = 0.0001; 12-month OR = 2.6 [1.6-7], P = 0.02). Increased daily step count while on HFVW independently predicted reduced odds of re-hospitalizations (1-month OR = 0.85[0.7-0.9], P = 0.005), 3-month OR = 0.95 [0.93-0.98], P = 0.003 and 1-month mortality (OR = 0.85 [0.7-0.95], P = 0.01), whereas CCI predicted adverse 12-month outcomes (OR = 1.2 [1.1-1.4], P = 0.03). CONCLUSIONS: Telehealth-guided specialist HFVW management for ADHF may offer a safe and efficacious alternative to hospitalization in suitable patients. Daily step count in HFVW can help predict risk of short-term adverse clinical outcomes.
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The mechanisms underlying plant succession remain highly debated. Due to the local scope of most studies, we lack a global quantification of the relative importance of species addition 'versus' replacement. We assessed the role of these processes in the variation (ß-diversity) of plant communities colonizing the forelands of 46 retreating glaciers worldwide, using both environmental DNA and traditional surveys. Our findings indicate that addition and replacement concur in determining community changes in deglaciated sites, but their relative importance varied over time. Taxa addition dominated immediately after glacier retreat, as expected in harsh environments, while replacement became more important for late-successional communities. These changes were aligned with total ß-diversity changes, which were more pronounced between early-successional communities than between late-successional communities (>50 yr since glacier retreat). Despite the complexity of community assembly during plant succession, the observed global pattern suggests a generalized shift from the dominance of facilitation and/or stochastic processes in early-successional communities to a predominance of competition later on.
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Camada de Gelo , PlantasRESUMO
Technological development has increased the use of chemical elements that have hitherto received scant scientific attention as environmental contaminants. Successful management of these rare trace elements (RTEs) requires elucidation of their mobility in the soil-plant system. We aimed to determine the capacity of Lolium perenne (a common pasture species) to tolerate and accumulate the RTEs Be, Ga, In, La, Ce, Nd, and Gd in a fluvial recent soil. Cadmium was used as a reference as a well-studied contaminant that is relatively mobile in the soil-plant system. Soil was spiked with 2.5-283 mg kg-1 of RTE or Cd salts, representing five, 10, 20, and 40 times their background concentrations in soil. For Be, Ce, In, and La, there was no growth reduction, even at the highest soil concentrations (76, 1132, 10.2, and 874 mg kg-1, respectively), which resulted in foliar concentrations of 7.1, 12, 0.11, and 50 mg kg-1, respectively. The maximum no-biomass reduction foliar concentrations for Cd, Gd, Nd, and Ga were 0.061, 0.1, 7.1, and 11 mg kg-1, respectively. Bioaccumulation coefficients ranged from 0.0030-0.95, and increased Ce < In < Nd â Gd < La â Be â Ga < Cd. Beryllium and La were the RTEs most at risk of entering the food chain via L. perenne, as their toxicity thresholds were not reached in the ranges tested, and the bioaccumulation coefficient (plant/soil concentration quotient) trends indicated that uptake would continue to increase at higher soil concentrations. In contrast, In and Ce were the elements least likely to enter the food chain. Further research should repeat the experiments in different soil types or with different plant species to test the robustness of the findings.
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OBJECTIVE: To assess the effect of a real world, ongoing telehealth service on the use of secondary healthcare. DESIGN: A retrospective observational study with anonymous matched controls. SETTING: Primary and community healthcare. Patients were recruited over 4 years in 89 general practices in Liverpool, UK and remotely managed by a dedicated clinical team in Liverpool Community Health. PARTICIPANTS: 5154 patients with chronic obstructive pulmonary disease, heart failure or diabetes were enrolled in the programme, of whom 3562 satisfied the inclusion criteria of this study. INTERVENTION: At least 9 weeks of telehealth including vital sign collection, questionnaires, education, support and informal coaching by clinical staff. PRIMARY OUTCOME: Reduction in the number of emergency admissions in the 12 months after start, compared with the year before start. Secondary subgroup analysis to improve future targeting and personalisation of the service. RESULT: The average number of emergency admissions for the intervention group at baseline is 0.35, 95% CI 0.32 to 0.38. The differential decrease in emergency admissions in the intervention group in comparison with the control group, the average treatment effect, is 0.08, 95 CI 0.05 to 0.11, corresponding to an average percentage decrease of 22.7%. In subgroup analysis, a score is calculated that can be used prospectively to predict individual benefit from the intervention. Patients with an above median score (37%) are predicted average reduction in emergency admissions of 0.15, 95% CI 0.09 to 0.2, corresponding to a percentage decrease in admissions of 25.3%. CONCLUSION: The telehealth intervention has a positive impact across a wide cohort of patients with different diseases. Prospective scoring of patients and allocation to targeted telehealth interventions is likely to improve the effectiveness and efficiency of the service.
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Atenção à Saúde/estatística & dados numéricos , Medicina Geral/estatística & dados numéricos , Admissão do Paciente/estatística & dados numéricos , Telemedicina/estatística & dados numéricos , Adulto , Idoso , Idoso de 80 Anos ou mais , Glicemia , Pressão Sanguínea , Peso Corporal , Diabetes Mellitus/sangue , Diabetes Mellitus/terapia , Emergências , Medicina Geral/métodos , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/terapia , Humanos , Pessoa de Meia-Idade , Oxigênio/sangue , Educação de Pacientes como Assunto , Avaliação de Programas e Projetos de Saúde , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Doença Pulmonar Obstrutiva Crônica/terapia , Estudos Retrospectivos , Inquéritos e Questionários , Telemedicina/métodos , Reino UnidoRESUMO
Iodine (I) is an essential trace element commonly deficient in agricultural systems. Whereas there is much information on I in food crops, there is a lacuna of knowledge on the environmental factors that affect pasture I concentrations. We aimed to identify the most important environmental factors affecting the concentration of I in New Zealand pastures, and the consequences to agricultural systems. Soil and pastoral samples were collected throughout the country and analyzed for I and other elements. The soils contained 1.1 to 86 mg I kg, with 0.005 to 1.4 mg kg in the pasture. In 26% of pastures, I concentrations were insufficient for sheep nutrition, whereas 87% contained insufficient I for cattle nutrition. Pasture I concentrations were negatively correlated with the distance from the sea, and the concentration of oxalate-extractable amorphous Al, Fe, and Si oxides, which immobilize soil I. Soil organic C and clay increased I retention in soil but did not significantly affect pasture I concentrations. Future work should investigate how soil properties affect pasture I uptake in inland areas.
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Iodo , Poluentes do Solo , Agricultura , Animais , Bovinos , Nova Zelândia , Ovinos , SoloRESUMO
For over 50 years, electron beams have been an important modality for providing an accurate dose of radiation to superficial cancers and disease and for limiting the dose to underlying normal tissues and structures. This review looks at many of the important contributions of physics and dosimetry to the development and utilization of electron beam therapy, including electron treatment machines, dose specification and calibration, dose measurement, electron transport calculations, treatment and treatment-planning tools, and clinical utilization, including special procedures. Also, future changes in the practice of electron therapy resulting from challenges to its utilization and from potential future technology are discussed.
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Elétrons/uso terapêutico , Física Médica/métodos , Aceleradores de Partículas/instrumentação , Planejamento da Radioterapia Assistida por Computador/instrumentação , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia/instrumentação , Radioterapia/métodos , Física Médica/instrumentação , Física Médica/tendências , Radioterapia/tendências , Planejamento da Radioterapia Assistida por Computador/tendênciasRESUMO
There is growing interest in the use of the Internet for interacting with patients, both in terms of healthcare information provision and information gathering. In this article, we examine the issues in designing healthcare websites for elderly users. In particular, this article uses a year-long case study of the development of a web-based system for self-reporting of symptoms and quality of life with a view to examine the issues relating to website design for elderly users. The issues identified included the technical, social and medical aspects of website design for elderly users. The web-based system developed was based on the European Quality of Life 5-Dimensions health-status questionnaire, a commonly used tool for patient self-reporting of quality of life, and the more specific coronary revascularisation outcome questionnaire. Currently, self-reporting is generally administered in the form of paper-based questionnaires to be completed in the outpatient clinic or at home. There are a variety of issues relating to elderly users, which imply that websites for elderly patients may involve different design considerations to other types of websites.
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Nível de Saúde , Internet , Qualidade de Vida , Autorrelato , Idoso , Idoso de 80 Anos ou mais , Atitude Frente aos Computadores , Feminino , Humanos , Masculino , Interface Usuário-ComputadorRESUMO
Evaluating conflicting theories about the influence of mountains on carbon dioxide cycling and climate requires understanding weathering fluxes from tectonically uplifting landscapes. The lack of soil production and weathering rate measurements in Earth's most rapidly uplifting mountains has made it difficult to determine whether weathering rates increase or decline in response to rapid erosion. Beryllium-10 concentrations in soils from the western Southern Alps, New Zealand, demonstrate that soil is produced from bedrock more rapidly than previously recognized, at rates up to 2.5 millimeters per year. Weathering intensity data further indicate that soil chemical denudation rates increase proportionally with erosion rates. These high weathering rates support the view that mountains play a key role in global-scale chemical weathering and thus have potentially important implications for the global carbon cycle.
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Altitude , Ciclo do Carbono , Solo/química , Tempo (Meteorologia) , Berílio/análise , Nova Zelândia , Radioisótopos/análiseRESUMO
PURPOSE: To provide historical background on the development and initial studies of the gynecological (gyn) applicators developed by Dr. Gilbert H. Fletcher, a radiation oncologist and chairperson from 1948 to 1981 of the department at the M.D. Anderson Hospital (MDAH) for Cancer Research in Houston, TX, and to acknowledge the previously unrecognized contribution that Dr. Leonard G. Grimmett, a radiation physicist and chairperson from 1949 to 1951 of the physics department at MDAH, made to the development of the gynecological applicators. METHODS AND MATERIALS: We reviewed archival materials from the Historical Resource Center and from the Department of Radiation Physics at The University of Texas M. D. Anderson Cancer Center, as well as contemporary published papers, to trace the history of the applicators. CONCLUSIONS: Dr. Fletcher's work was influenced by the work on gynecologic applicators in the 1940s in Europe, especially work done at the Royal Cancer Hospital in London. Those efforts influenced not only Dr. Fletcher's approach to the design of the applicators but also the methods used to perform in vivo measurements and determine the dose distribution. Much of the initial development of the dosimetry techniques and measurements at MDAH were carried out by Dr. Grimmett.
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Braquiterapia/história , Institutos de Câncer/história , Neoplasias do Colo do Útero/história , Braquiterapia/instrumentação , Desenho de Equipamento/história , Feminino , Ginecologia/história , Ginecologia/instrumentação , História do Século XX , Humanos , Texas , Neoplasias do Colo do Útero/radioterapiaRESUMO
In a Croatian outdoor pig breeding unit 32 sows (died between days 2 and 14 post partum) were subjected to gross pathological and further laboratory investigations. Necropsy findings revealed tympany and purple discoloration of the skin, the surface of the livers was dark and had honeycomb appearance with gas bubble infiltrations, congested lungs, hemorrhages, serosanguinous exsudates in body cavities and the stomachs were full. Gram-stains of smears revealed large numbers of Gram-positive rods. Anaerobic cultures yielded high numbers of Clostridium (C.) novyi and fluorescent antibody test (FAT) confirmed this diagnosis. Enzyme immunoassay and toxin testing by neutralisation in Chinese hamster ovary cells revealed toxin B. Based upon the clinical symptoms, gross-pathological signs, bacteriological findings and toxin testing we concluded that C. novyi caused sow mortality. Suboptimal outdoor environment and high outdoor infectious pressure might have contributed the C. novyi caused losses in this unit.