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1.
Proc Natl Acad Sci U S A ; 121(25): e2321441121, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38861597

RESUMO

Legacy effects describe the persistent, long-term impacts on an ecosystem following the removal of an abiotic or biotic feature. Redlining, a policy that codified racial segregation and disinvestment in minoritized neighborhoods, has produced legacy effects with profound impacts on urban ecosystem structure and health. These legacies have detrimentally impacted public health outcomes, socioeconomic stability, and environmental health. However, the collateral impacts of redlining on wildlife communities are uncertain. Here, we investigated whether faunal biodiversity was associated with redlining. We used home-owner loan corporation (HOLC) maps [grades A (i.e., "best" and "greenlined"), B, C, and D (i.e., "hazardous" and "redlined")] across four cities in California and contributory science data (iNaturalist) to estimate alpha and beta diversity across six clades (mammals, birds, insects, arachnids, reptiles, and amphibians) as a function of HOLC grade. We found that in greenlined neighborhoods, unique species were detected with less sampling effort, with redlined neighborhoods needing over 8,000 observations to detect the same number of unique species. Historically redlined neighborhoods had lower native and nonnative species richness compared to greenlined neighborhoods across each city, with disparities remaining at the clade level. Further, community composition (i.e., beta diversity) consistently differed among HOLC grades for all cities, including large differences in species assemblage observed between green and redlined neighborhoods. Our work spotlights the lasting effects of social injustices on the community ecology of cities, emphasizing that urban conservation and management efforts must incorporate an antiracist, justice-informed lens to improve biodiversity in urban environments.


Assuntos
Animais Selvagens , Biodiversidade , Cidades , Animais , California , Ecossistema , Humanos , Conservação dos Recursos Naturais
2.
Proc Natl Acad Sci U S A ; 120(35): e2305050120, 2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37603760

RESUMO

Primary productivity response to climatic drivers varies temporally, indicating state-dependent interactions between climate and productivity. Previous studies primarily employed equation-based approaches to clarify this relationship, ignoring the state-dependent nature of ecological dynamics. Here, using 40 y of climate and productivity data from 48 grassland sites across Mongolia, we applied an equation-free, nonlinear time-series analysis to reveal sensitivity patterns of productivity to climate change and variability and clarify underlying mechanisms. We showed that productivity responded positively to annual precipitation in mesic regions but negatively in arid regions, with the opposite pattern observed for annual mean temperature. Furthermore, productivity responded negatively to decreasing annual aridity that integrated precipitation and temperature across Mongolia. Productivity responded negatively to interannual variability in precipitation and aridity in mesic regions but positively in arid regions. Overall, interannual temperature variability enhanced productivity. These response patterns are largely unrecognized; however, two mechanisms are inferable. First, time-delayed climate effects modify annual productivity responses to annual climate conditions. Notably, our results suggest that the sensitivity of annual productivity to increasing annual precipitation and decreasing annual aridity can even be negative when the negative time-delayed effects of annual precipitation and aridity on productivity prevail across time. Second, the proportion of plant species resistant to water and temperature stresses at a site determines the sensitivity of productivity to climate variability. Thus, we highlight the importance of nonlinear, state-dependent sensitivity of productivity to climate change and variability, accurately forecasting potential biosphere feedback to the climate system.

3.
Diabetologia ; 2024 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-39155282

RESUMO

A panel of primary care and diabetes specialists conducted focused literature searches on the current role of glycaemic control in the management of type 2 diabetes and revisited the evolution of evidence supporting the importance of early and intensive blood glucose control as a central strategy to reduce the risk of adverse long-term outcomes. The optimal approach to type 2 diabetes management has evolved over time as the evidence base has expanded from data from trials that established the role of optimising glycaemic control to recent data from cardiovascular outcomes trials (CVOTs) demonstrating organ-protective effects of newer glucose-lowering drugs (GLDs). The results from these CVOTs were derived mainly from people with type 2 diabetes and prior cardiovascular and kidney disease or multiple risk factors. In more recent years, earlier diagnosis in high-risk individuals has contributed to the large proportion of people with type 2 diabetes who do not have complications. In these individuals, a legacy effect of early and optimal control of blood glucose and cardiometabolic risk factors has been proven to reduce cardiovascular and kidney disease events and all-cause mortality. As there is a lack of RCTs investigating the potential synergistic effects of intensive glucose control and organ-protective effects of newer GLDs, this article re-evaluates the evolution of the scientific evidence and highlights the importance of integrating glycaemic control as a pivotal early therapeutic goal in most people with type 2 diabetes, while targeting existing cardiovascular and kidney disease. We also emphasise the importance of implementing multifactorial management using a multidisciplinary approach to facilitate regular review, patient empowerment and the possibility of tailoring interventions to account for the heterogeneity of type 2 diabetes.

4.
Ecol Lett ; 27(3): e14384, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38426584

RESUMO

Although native species diversity is frequently reported to enhance invasion resistance, within-species diversity of native plants can also moderate invasions. While the positive diversity-invasion resistance relationship is often attributed to competition, indirect effects mediated through plant-soil feedbacks can also influence the relationship. We manipulated the genotypic diversity of an endemic species, Scirpus mariqueter, and evaluated the effects of abiotic versus biotic feedbacks on the performance of a global invader, Spartina alterniflora. We found that invader performance on live soils decreased non-additively with genotypic diversity of the native plant that trained the soils, but this reversed when soils were sterilized to eliminate feedbacks through soil biota. The influence of soil biota on the feedback was primarily associated with increased levels of microbial biomass and fungal diversity in soils trained by multiple-genotype populations. Our findings highlight the importance of plant-soil feedbacks mediating the positive relationship between genotypic diversity and invasion resistance.


Assuntos
Plantas , Solo , Retroalimentação , Poaceae , Genótipo , Microbiologia do Solo , Espécies Introduzidas
5.
Proc Biol Sci ; 291(2015): 20231887, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38228179

RESUMO

Arctic birds and mammals are physiologically adapted to survive in cold environments but live in the fastest warming region on the planet. They should therefore be most threatened by climate change. We fitted a phylogenetic model of upper critical temperature (TUC) in 255 bird species and determined that TUC for dovekies (Alle alle; 22.4°C)-the most abundant seabird in the Arctic-is 8.8°C lower than predicted for a bird of its body mass (150 g) and habitat latitude. We combined our comparative analysis with in situ physiological measurements on 36 dovekies from East Greenland and forward-projections of dovekie energy and water expenditure under different climate scenarios. Based on our analyses, we demonstrate that cold adaptation in this small Arctic seabird does not handicap acute tolerance to air temperatures up to at least 15°C above their current maximum. We predict that climate warming will reduce the energetic costs of thermoregulation for dovekies, but their capacity to cope with rising temperatures will be constrained by water intake and salt balance. Dovekies evolved 15 million years ago, and their thermoregulatory physiology might also reflect adaptation to a wide range of palaeoclimates, both substantially warmer and colder than the present day.


Assuntos
Charadriiformes , Ecossistema , Animais , Filogenia , Charadriiformes/fisiologia , Aves , Mudança Climática , Mamíferos , Regiões Árticas
6.
New Phytol ; 242(3): 858-869, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38375596

RESUMO

A conceptual understanding on how the vegetation's carbon (C) balance is determined by source activity and sink demand is important to predict its C uptake and sequestration potential now and in the future. We have gathered trajectories of photosynthesis and growth as a function of environmental conditions described in the literature and compared them with current concepts of source and sink control. There is no clear evidence for pure source or sink control of the C balance, which contradicts recent hypotheses. Using model scenarios, we show how legacy effects via structural and functional traits and antecedent environmental conditions can alter the plant's carbon balance. We, thus, combined the concept of short-term source-sink coordination with long-term environmentally driven legacy effects that dynamically acclimate structural and functional traits over time. These acclimated traits feedback on the sensitivity of source and sink activity and thus change the plant physiological responses to environmental conditions. We postulate a whole plant C-coordination system that is primarily driven by stomatal optimization of growth to avoid a C source-sink mismatch. Therefore, we anticipate that C sequestration of forest ecosystems under future climate conditions will largely follow optimality principles that balance water and carbon resources to maximize growth in the long term.


Assuntos
Carbono , Ecossistema , Fotossíntese/fisiologia , Clima , Fenótipo , Dióxido de Carbono , Sequestro de Carbono
7.
New Phytol ; 241(6): 2575-2588, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38087806

RESUMO

Plants can suppress the growth of other plants by modifying soil properties. These negative plant-soil feedbacks are often species-specific, suggesting that some plants possess resistance strategies. However, the underlying mechanisms remain largely unknown. Here, we investigated whether benzoxazinoids, a class of dominant secondary metabolites that are exuded into the soil by maize and other cereals, allow maize plants to cope with plant-soil feedbacks. We find that three out of five tested crop species reduce maize (Zea mays L.) performance via negative plant-soil feedbacks relative to the mean across species. This effect is partially alleviated by the capacity of maize plants to produce benzoxazinoids. Soil complementation with purified benzoxazinoids restores the protective effect for benzoxazinoid-deficient mutants. Sterilization and reinoculation experiments suggest that benzoxazinoid-mediated protection acts via changes in soil biota. Substantial variation of the protective effect between experiments and soil types illustrates context dependency. In conclusion, exuded plant secondary metabolites allow plants to cope with plant-soil feedbacks. These findings expand the functional repertoire of plant secondary metabolites and reveal a mechanism by which plants can resist negative effects of soil feedbacks. The uncovered phenomenon may represent a promising avenue to stabilize plant performance in crop rotations.


Assuntos
Benzoxazinas , Solo , Benzoxazinas/farmacologia , Benzoxazinas/metabolismo , Retroalimentação , Plantas/metabolismo , Zea mays/metabolismo
8.
New Phytol ; 242(5): 2223-2236, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38548693

RESUMO

Microbial communities can rapidly respond to stress, meaning plants may encounter altered soil microbial communities in stressful environments. These altered microbial communities may then affect natural selection on plants. Because stress can cause lasting changes to microbial communities, microbes may also cause legacy effects on plant selection that persist even after the stress ceases. To explore how microbial responses to stress and persistent microbial legacy effects of stress affect natural selection, we grew Chamaecrista fasciculata plants in stressful (salt, herbicide, or herbivory) or nonstressful conditions with microbes that had experienced each of these environments in the previous generation. Microbial community responses to stress generally counteracted the effects of stress itself on plant selection, thereby weakening the strength of stress as a selective agent. Microbial legacy effects of stress altered plant selection in nonstressful environments, suggesting that stress-induced changes to microbes may continue to affect selection after stress is lifted. These results suggest that soil microbes may play a cryptic role in plant adaptation to stress, potentially reducing the strength of stress as a selective agent and altering the evolutionary trajectory of plant populations.


Assuntos
Seleção Genética , Estresse Fisiológico , Microbiologia do Solo , Herbivoria , Herbicidas/farmacologia
9.
New Phytol ; 242(6): 2495-2509, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38641748

RESUMO

Extreme droughts can have long-lasting effects on forest community dynamics and species interactions. Yet, our understanding of how drought legacy modulates ecological relationships is just unfolding. We tested the hypothesis that leaf chemistry and herbivory show long-term responses to premature defoliation caused by an extreme drought event in European beech (Fagus sylvatica L.). For two consecutive years after the extreme European summer drought in 2018, we collected leaves from the upper and lower canopy of adjacently growing drought-stressed and unstressed trees. Leaf chemistry was analyzed and leaf damage by different herbivore-feeding guilds was quantified. We found that drought had lasting impacts on leaf nutrients and on specialized metabolomic profiles. However, drought did not affect the primary metabolome. Drought-related phytochemical changes affected damage of leaf-chewing herbivores whereas damage caused by other herbivore-feeding guilds was largely unaffected. Drought legacy effects on phytochemistry and herbivory were often weaker than between-year or between-canopy strata variability. Our findings suggest that a single extreme drought event bears the potential to long-lastingly affect tree-herbivore interactions. Drought legacy effects likely become more important in modulating tree-herbivore interactions since drought frequency and severity are projected to globally increase in the coming decades.


Assuntos
Secas , Fagus , Herbivoria , Compostos Fitoquímicos , Folhas de Planta , Fagus/fisiologia , Herbivoria/fisiologia , Folhas de Planta/fisiologia , Animais , Metaboloma
10.
Glob Chang Biol ; 30(1): e17048, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37988193

RESUMO

Understanding the mechanisms by which individual organisms respond and populations adapt to global climate change is a critical challenge. The role of plasticity and acclimation, within and across generations, may be essential given the pace of change. We investigated plasticity across generations and life stages in response to ocean acidification (OA), which poses a growing threat to both wild populations and the sustainable aquaculture of shellfish. Most studies of OA on shellfish focus on acute effects, and less is known regarding the longer term carryover effects that may manifest within or across generations. We assessed these longer term effects in red abalone (Haliotis rufescens) using a multi-generational split-brood experiment. We spawned adults raised in ambient conditions to create offspring that we then exposed to high pCO2 (1180 µatm; simulating OA) or low pCO2 (450 µatm; control or ambient conditions) during the first 3 months of life. We then allowed these animals to reach maturity in ambient common garden conditions for 4 years before returning the adults into high or low pCO2 treatments for 11 months and measuring growth and reproductive potential. Early-life exposure to OA in the F1 generation decreased adult growth rate even after 5 years especially when abalone were re-exposed to OA as adults. Adult but not early-life exposure to OA negatively impacted fecundity. We then exposed the F2 offspring to high or low pCO2 treatments for the first 3 months of life in a fully factorial, split-brood design. We found negative transgenerational effects of parental OA exposure on survival and growth of F2 offspring, in addition to significant direct effects of OA on F2 survival. These results show that the negative impacts of OA can last within and across generations, but that buffering against OA conditions at critical life-history windows can mitigate these effects.


Assuntos
Gastrópodes , Água do Mar , Animais , Concentração de Íons de Hidrogênio , Acidificação dos Oceanos , Dióxido de Carbono/efeitos adversos , Reprodução , Gastrópodes/fisiologia
11.
Glob Chang Biol ; 30(6): e17376, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38923195

RESUMO

A defining feature of the Anthropocene is the distortion of the biosphere phosphorus (P) cycle. A relatively sudden acceleration of input fluxes without a concomitant increase in output fluxes has led to net accumulation of P in the terrestrial-aquatic continuum. Over the past century, P has been mined from geological deposits to produce crop fertilizers. When P inputs are not fully removed with harvest of crop biomass, the remaining P accumulates in soils. This residual P is a uniquely anthropogenic pool of P, and its management is critical for agronomic and environmental sustainability. Managing residual P first requires its quantification-but measuring residual P is challenging. In this review, we synthesize approaches to quantifying residual P, with emphasis on advantages, disadvantages, and complementarity. Common approaches to estimate residual P are mass balances, long-term experiments, soil test P trends and chronosequences, with varying suitability or even limitations to distinct spatiotemporal scales. We demonstrate that individual quantification approaches are (i) constrained, (ii) often complementary, and (iii) may be feasible at only certain time-space scales. While some of these challenges are inherent to the quantification approach, in many cases there are surmountable challenges that can be addressed by unifying existing P pool and flux datasets, standardizing and synchronizing data collection on pools and fluxes, and quantifying uncertainty. Though defined as a magnitude, the distribution and speciation of residual P is relatively less understood but shapes its utilization and environmental impacts. The form of residual P will vary by agroecosystem context due to edaphoclimatic-specific transformation of the accumulated P, which has implications for management (e.g., crop usage) and future policies (e.g., lag times in P loading from non-point sources). Quantifying the uncertainty in measuring residual P holds value beyond scientific understanding, as it supports prioritization of monitoring and management resources and inform policy.


Assuntos
Fósforo , Fósforo/análise , Solo/química , Monitoramento Ambiental/métodos , Fertilizantes/análise , Ecossistema , Agricultura/métodos
12.
Glob Chang Biol ; 30(5): e17287, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38695768

RESUMO

While droughts predominantly induce immediate reductions in plant carbon uptake, they can also exert long-lasting effects on carbon fluxes through associated changes in leaf area, soil carbon, etc. Among other mechanisms, shifts in carbon allocation due to water stress can contribute to the legacy effects of drought on carbon fluxes. However, the magnitude and impact of these allocation shifts on carbon fluxes and pools remain poorly understood. Using data from a wet tropical flux tower site in French Guiana, we demonstrate that drought-induced carbon allocation shifts can be reliably inferred by assimilating Net Biosphere Exchange (NBE) and other observations within the CARbon DAta MOdel fraMework. This model-data fusion system allows inference of optimized carbon and water cycle parameters and states from multiple observational data streams. We then examined how these inferred shifts affected the duration and magnitude of drought's impact on NBE during and after the extreme event. Compared to a static allocation scheme analogous to those typically implemented in land surface models, dynamic allocation reduced average carbon uptake during drought recovery by a factor of 2.8. Additionally, the dynamic model extended the average recovery time by 5 months. The inferred allocation shifts influenced the post-drought period by altering foliage and fine root pools, which in turn modulated gross primary productivity and heterotrophic respiration for up to a decade. These changes can create a bust-boom cycle where carbon uptake is enhanced some years after a drought, compared to what would have occurred under drought-free conditions. Overall, allocation shifts accounted for 65% [45%-75%] of drought legacy effects in modeled NBE. In summary, drought-induced carbon allocation shifts can play a substantial role in the enduring influence of drought on cumulative land-atmosphere CO2 exchanges and should be accounted for in ecosystem models.


Assuntos
Ciclo do Carbono , Secas , Clima Tropical , Guiana Francesa , Florestas , Carbono/metabolismo , Modelos Teóricos
13.
Diabetes Metab Res Rev ; 40(1): e3711, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37634071

RESUMO

AIMS: To examine whether early treatment intensification using dipeptidyl-peptidase 4 inhibitors (DPP4i) delays insulin initiation in Chinese patients diagnosed with type 2 diabetes for less than 5 years. MATERIALS AND METHODS: In a territory-wide prospective cohort study, patients with type 2 diabetes initiating DPP4i at diabetes duration <2 years (early intensification) and 3-5 years (late intensification) were matched using 1:1 propensity-score matching (n = 908 in each arm). We used Cox regression to compare the risk of insulin initiation between the two groups. We explored the interactive and mediation effects of glycated haemoglobin (HbA1c) variability score (HVS), defined as the percentage of HbA1c varying by ≥0.5% compared with preceding values. RESULTS: Of 1816 patients (60.7% men, mean age 54.4 ± 11.9 years), 92.4% and 71.9% were treated with metformin and sulphonylureas respectively at DPP4i initiation. Early DPP4i intensification [hazard ratio (HR) 0.71, (95% CI 0.58-0.68)] and low HVS (<50%) (HR = 0.40, 0.33-0.50) were associated with delayed insulin initiation during a median 4.08 years of follow-up. Early intensification with low HVS had the lowest risk versus late intensification with high HVS (HR = 0.30, 0.22-0.40) (pinteraction  = 0.013). HVS mediated 19.5% of the total effect of early DPP4i intensification on delaying insulin initiation. The late and early intensification groups had similar HbA1c at month 0 (8.4 ± 1.3% vs. 8.4 ± 1.5%) and month 3 (7.6 ± 1.2% vs. 7.6 ± 1.3%) after DPP4i initiation. By month 12, HbA1c in the late intensification group deteriorated (7.9 ± 1.4%) but remained stable in the early intensification group (7.6 ± 1.4%, p = 0.001) with persistent between-group difference over 72 months (8.2 ± 1.7% vs. 7.7 ± 1.6%, p = 0.001). CONCLUSIONS: In type 2 diabetes, early DPP4i intensification delayed insulin initiation, partially explained by reduced glycaemic variability.


Assuntos
Diabetes Mellitus Tipo 2 , Inibidores da Dipeptidil Peptidase IV , Masculino , Humanos , Adulto , Pessoa de Meia-Idade , Idoso , Feminino , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/diagnóstico , Inibidores da Dipeptidil Peptidase IV/uso terapêutico , Estudos de Coortes , Insulina/uso terapêutico , Hipoglicemiantes/uso terapêutico , Hipoglicemiantes/farmacologia , Hemoglobinas Glicadas , Pontuação de Propensão , Estudos Prospectivos , Estudos Retrospectivos , Insulina Regular Humana
14.
Ecol Appl ; : e3006, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39030911

RESUMO

Enhancing resilience in formerly degraded ecosystems is an important goal of restoration ecology. However, evidence for the recovery of resilience and its underlying mechanisms require long-term experiments and comparison with reference ecosystems. We used data from an experimental prairie restoration that featured long-term soil heterogeneity manipulations and data from two long-term experiments located in a comparable remnant (reference) prairie to (1) quantify the recovery of ecosystem functioning (i.e., productivity) relative to remnant prairie, (2) compare the resilience of restored and remnant prairies to a natural drought, and (3) test whether soil heterogeneity enhances resilience of restored prairie. We compared sensitivity and legacy effects between prairie types (remnant and restored) and among four prairie sites that included two remnant prairie sites and prairie restored under homogeneous and heterogeneous soil conditions. We measured sensitivity and resilience as the proportional change in aboveground net primary productivity (ANPP) during and following drought (sensitivity and legacy effects, respectively) relative to average ANPP based on 4 pre-drought years (2014-2017). In nondrought years, total ANPP was similar between remnant and restored prairie, but remnant prairie had higher grass productivity and lower forb productivity compared with restored prairie. These ANPP patterns generally persisted during drought. The sensitivity of total ANPP to drought was similar between restored and remnant prairie, but grasses in the restored prairie were more sensitive to drought. Post-drought legacy effects were more positive in the restored prairie, and we attributed this to the more positive and less variable legacy response of forb ANPP in the restored prairie, especially in the heterogeneous soil treatment. Our results suggest that productivity recovers in restored prairie and exhibits similar sensitivity to drought as in remnant prairie. Furthermore, creating heterogeneity promotes forb productivity and enhances restored prairie resilience to drought.

15.
Ecol Appl ; : e3007, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38982756

RESUMO

Humans have profoundly altered phosphorus (P) cycling across scales. Agriculturally driven changes (e.g., excessive P-fertilization and manure addition), in particular, have resulted in pronounced P accumulations in soils, often known as "soil legacy P." These legacy P reserves serve as persistent and long-term nonpoint sources, inducing downstream eutrophication and ecosystem services degradation. While there is considerable scientific and policy interest in legacy P, its fine-scale spatial heterogeneity, underlying drivers, and scales of variance remain unclear. Here we present an extensive field sampling (150-m interval grid) and analysis of 1438 surface soils (0-15 cm) in 2020 for two typical subtropical grassland types managed for livestock production: Intensively managed (IM) and Semi-natural (SN) pastures. We ask the following questions: (1) What is the spatial variability, and are there hotspots of soil legacy P? (2) Does soil legacy P vary primarily within pastures, among pastures, or between pasture types? (3) How does soil legacy P relate to pasture management intensity, soil and geographic characteristics? and (4) What is the relationship between soil legacy P and aboveground plant tissue P concentration? Our results showed that three measurements of soil legacy P (total P, Mehlich-1, and Mehlich-3 extractable P representing labile P pools) varied substantially across the landscape. Spatial autoregressive models revealed that soil organic matter, pH, available Fe and Al, elevation, and pasture management intensity were crucial predictors for spatial patterns of soil P, although models were more reliable for predicting total P (68.9%) than labile P. Our analysis further demonstrated that total variance in soil legacy P was greater in IM than SN pastures, and intensified pasture management rescaled spatial patterns of soil legacy P. In particular, after controlling for sample size, soil P was extremely variable at small scales, with variance diminished as spatial scale increased. Our results suggest that broad pasture- or farm-level best management practices may be limited and less efficient, especially for more IM pastures. Rather, management to curtail soil legacy P and mitigate P loading and losses should be implemented at fine scales designed to target spatially distinct P hotspots across the landscape.

16.
J Anim Ecol ; 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39138820

RESUMO

Body size and growth rate can influence individual and population success by mediating fitness. Understanding the factors that influence growth can be difficult to disentangle, however, because growth can be shaped by environmental conditions recently experienced, as well as legacy effects from conditions experienced earlier in life and by parents (via parental effects). To improve understanding of growth among annual cohorts (1982-2015) of Lake Erie Walleye (Sander vitreus), a species with life-history and growth characteristics similar to many other long-lived, iteroparous fishes, we determined the role of the following hypothesised factors: (H1) recent environmental conditions; (H2) traits and experiences of the cohort, including growth, in the previous year; (H3) early-life cohort density; (H4) early-life body size; and (H5) parental composition and environment. We evaluated the relative importance of these hypothesised factors using piecewise structural equation modelling in an information-theoretic framework. Our results indicated that cohort-specific growth of Lake Erie Walleye was most strongly influenced by traits (growth) and experiences of the cohort during the previous year (H2) and parental composition and environment (H5). The observed negative relationship with growth during the previous year may indicate that Walleye exhibit compensatory growth. The relationships with parental sizes and environments may mean that parental contributions to offspring affects cohorts into adulthood, with serious implications for the effects of climate change. Warm winters appear to negatively influence offspring growth performance for many years. Legacy effects had a stronger influence on cohort growth than recent environmental conditions, providing new understanding of how somatic growth is regulated in Lake Erie's Walleye population. Specifically, the parental composition and environment appear important via epigenetic and/or egg-provisioning legacies, with carryover effects modifying growth among years. Ultimately, our findings demonstrate that understanding recent growth in animal populations similar to Lake Erie Walleye may require knowledge of past conditions, including those experienced by parents.

17.
Pediatr Blood Cancer ; 71(8): e31066, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38757484

RESUMO

BACKGROUND: Legacy-oriented interventions have the potential to offer pediatric oncology patients and families comfort at end of life and during bereavement. Certified child life specialists often provide these services, and presently little is known about whether disparities exist in the provision of legacy-oriented interventions. METHODS: In this retrospective decedent cohort study, we examined demographic and clinical characteristics from a sample of 678 pediatric oncology patients who died between 2015 and 2019. Bivariate analysis assessed differences between patients who received any versus no legacy-oriented intervention. Uni- and multivariable logistic regression models assessed associations of baseline characteristics and likelihood of receiving legacy-oriented intervention. Further multivariable analysis explored joint effects of significant variables identified in the univariable analysis. RESULTS: Fifty-two percent of patients received a legacy-oriented intervention. Older adolescents (≥13 years) were less likely (odds ratio [OR]: 1.73, p = .007) to receive legacy-oriented interventions than younger ones. Patients with home/hospice deaths were also less likely (OR: 19.98, p < .001) to receive interventions compared to patients who passed away at SJCRH locations. Hispanic patients (OR: 1.53, p = .038) and those in palliative care (OR: 10.51, p < .001) were more likely to receive interventions. No significant race association was noted. CONCLUSION: All children and adolescents with cancer deserve quality care at end of life, including access to legacy-oriented interventions, yet nearly half of patients in this cohort did not receive these services. By identifying demographic and clinical characteristics associated with decreased odds of receiving legacy-oriented interventions, healthcare professionals can modify end-of-life care processes to improve access. Introducing legacy-oriented interventions early and increasing exposure in community spaces may enhance access to legacy-oriented interventions for pediatric oncology patients.


Assuntos
Neoplasias , Assistência Terminal , Humanos , Masculino , Feminino , Criança , Adolescente , Estudos Retrospectivos , Neoplasias/terapia , Neoplasias/mortalidade , Pré-Escolar , Lactente , Acessibilidade aos Serviços de Saúde , Cuidados Paliativos , Seguimentos , Recém-Nascido , Prognóstico , Oncologia , Luto
18.
Pediatr Blood Cancer ; : e31272, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39138603

RESUMO

Honoring a child's legacy is an essential aspect of meaning-making for bereaved parents, yet little is known about storytelling as a mechanism. Through narrative analysis of 19 bereaved parent interviews focused on legacy, we examined the role of storytelling in creating and sustaining legacy. Most participants (89%) told stories centered around the child's impact and parent's coping, including the child's character and interpersonal relationships during and after their lifetime as well as how the child's legacy influenced parents' grief experiences. Future research is needed to explore the potential impact of storytelling initiatives to support legacy-making for bereaved caregivers.

19.
Environ Sci Technol ; 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39136670

RESUMO

Surface water and sediments from the Jackpile mine, St. Anthony mine, Rio Paguate, Rio Moquino, and Mesita Dam areas near Pueblo of Laguna, New Mexico, were analyzed for 226Ra and U using gamma (γ) spectroscopy and inductively coupled plasma mass spectroscopy, respectively. Activity ratios for 226Ra/238U for solid samples range from 0.34 ± 0.13 to 16 ± 2.9, which reflect uranium transport and accumulation (<1), relatively pristine material in secular equilibrium (1), and removal of uranium by weathering (>1). Concentrations ranging from 80 to 225 µg L-1 U were detected in unfiltered water samples near the Jackpile mine. Water samples upstream and downstream from the mine contained concentrations ranging from 12 to 15 µg L-1 U. Water samples collected from the North Pit standing pond in the Jackpile mine contained as much as 1560 pCi L-1 of 226Ra, and passing the water through a 0.2 µM filter did not substantially reduce the activity of 226Ra in the water. 234Th and 226Ra are in secular equilibrium in this water, while radon gas was lost from the water. The results of the current study provide insight into the distribution of U-series radionuclides in the Pueblo of Laguna area, including detection of high levels of radioactivity in water at some locations within the Jackpile mine.

20.
Environ Sci Technol ; 58(24): 10806-10816, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38829301

RESUMO

Temporal and spatial variability of per- and polyfluoroalkyl substances (PFASs) in herring, cod, eelpout, and guillemot covering four decades and more than 1000 km in the Baltic Sea was investigated to evaluate the effect of PFAS regulations and residence times of PFASs. Overall, PFAS concentrations responded rapidly to recent regulations but with some notable basin- and homologue-specific variability. The well-ventilated Kattegat and Bothnian Bay showed a faster log-linear decrease for most PFASs than the Baltic Proper, which lacks a significant loss mechanism. PFOS and FOSA, for example, have decreased with 0-7% y-1 in the Baltic Proper and 6-16% y-1 in other basins. PFNA and partly PFOA are exceptions and continue to show stagnant or increasing concentrations. Further, we found that Bothnian Bay herring contained the highest concentrations of >C12 perfluoroalkyl carboxylic acids (PFCAs), likely from rivers with high loads of dissolved organic carbon. In the Kattegat, low PFAS concentrations, but a high FOSA fraction, could be due to influence from the North Sea inflow below the halocline and possibly a local source of FOSA and/or isomer-specific biotransformation. This study represents the most comprehensive spatial and temporal investigation of PFASs in Baltic wildlife while providing new insights into cycling of PFASs within the Baltic Sea ecosystem.


Assuntos
Monitoramento Ambiental , Fluorocarbonos , Poluentes Químicos da Água , Poluentes Químicos da Água/análise , Fluorocarbonos/análise , Oceanos e Mares , Animais
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