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1.
Proc Natl Acad Sci U S A ; 121(17): e2305517121, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38621135

RESUMO

Growing crops in more diverse crop systems (i.e., intercropping) is one way to produce food more sustainably. Even though intercropping, compared to average monocultures, is generally more productive, the full yield potential of intercropping might not yet have been achieved as modern crop cultivars are bred to be grown in monoculture. Breeding plants for more familiarity in mixtures, i.e., plants that are adapted to more diverse communities (i.e., adaptation) or even to coexist with each other (i.e., coadaptation) might have the potential to sustainably enhance productivity. In this study, the productivity benefits of familiarity through evolutionary adaptation and coevolutionary coadaptation were disentangled in a crop system through an extensive common garden experiment. Furthermore, evolutionary and coevolutionary effects on species-level and community-level productivity were linked to corresponding changes in functional traits. We found evidence for higher productivity and trait convergence with increasing familiarity with the plant communities. Furthermore, our results provide evidence for the coevolution of plants in mixtures leading to higher productivity of coadapted species. However, with the functional traits measured in our study, we could not fully explain the productivity benefits found upon coevolution. Our study investigated coevolution among randomly interacting plants and was able to demonstrate that coadaptation through coevolution of coexisting species in mixtures occurs and promotes ecosystem functioning (i.e., higher productivity). This result is particularly relevant for the diversification of agricultural and forest ecosystems, demonstrating the added value of artificially selecting plants for the communities they are familiar with.


Assuntos
Ecossistema , Melhoramento Vegetal , Agricultura/métodos , Produtos Agrícolas , Evolução Biológica
2.
Proc Natl Acad Sci U S A ; 121(13): e2313334121, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38498717

RESUMO

Multiple facets of global change affect the earth system interactively, with complex consequences for ecosystem functioning and stability. Simultaneous climate and biodiversity change are of particular concern, because biodiversity may contribute to ecosystem resistance and resilience and may mitigate climate change impacts. Yet, the extent and generality of how climate and biodiversity change interact remain insufficiently understood, especially for the decomposition of organic matter, a major determinant of the biosphere-atmosphere carbon feedbacks. With an inter-biome field experiment using large rainfall exclusion facilities, we tested how drought, a common prediction of climate change models for many parts of the world, and biodiversity in the decomposer system drive decomposition in forest ecosystems interactively. Decomposing leaf litter lost less carbon (C) and especially nitrogen (N) in five different forest biomes following partial rainfall exclusion compared to conditions without rainfall exclusion. An increasing complexity of the decomposer community alleviated drought effects, with full compensation when large-bodied invertebrates were present. Leaf litter mixing increased diversity effects, with increasing litter species richness, which contributed to counteracting drought effects on C and N loss, although to a much smaller degree than decomposer community complexity. Our results show at a relevant spatial scale covering distinct climate zones that both, the diversity of decomposer communities and plant litter in forest floors have a strong potential to mitigate drought effects on C and N dynamics during decomposition. Preserving biodiversity at multiple trophic levels contributes to ecosystem resistance and appears critical to maintain ecosystem processes under ongoing climate change.


Assuntos
Secas , Ecossistema , Biodiversidade , Florestas , Folhas de Planta , Carbono
3.
Proc Natl Acad Sci U S A ; 120(30): e2213768120, 2023 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-37463211

RESUMO

Adversity exposures in the prenatal and postnatal period are associated with an increased risk for psychopathology, which can be perpetuated across generations. Nonhuman animal research highlights the gut microbiome as a putative biological mechanism underlying such generational risks. In a sample of 450 mother-child dyads living in Singapore, we examined associations between three distinct adversity exposures experienced across two generations-maternal childhood maltreatment, maternal prenatal anxiety, and second-generation children's exposure to stressful life events-and the gut microbiome composition of second-generation children at 2 y of age. We found distinct differences in gut microbiome profiles linked to each adversity exposure, as well as some nonaffected microbiome features (e.g., beta diversity). Remarkably, some of the microbial taxa associated with concurrent and prospective child socioemotional functioning shared overlapping putative functions with those affected by adversity, suggesting that the intergenerational transmission of adversity may have a lasting impact on children's mental health via alterations to gut microbiome functions. Our findings open up a new avenue of research into the underlying mechanisms of intergenerational transmission of mental health risks and the potential of the gut microbiome as a target for intervention.


Assuntos
Microbioma Gastrointestinal , Microbiota , Feminino , Animais , Gravidez , Humanos , Pré-Escolar , Estudos Prospectivos , Psicopatologia , Saúde Mental
4.
Circulation ; 149(13): e997-e1022, 2024 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-38385268

RESUMO

Over the past decade, new research has advanced scientific knowledge of neurodevelopmental trajectories, factors that increase neurodevelopmental risk, and neuroprotective strategies for individuals with congenital heart disease. In addition, best practices for evaluation and management of developmental delays and disorders in this high-risk patient population have been formulated based on literature review and expert consensus. This American Heart Association scientific statement serves as an update to the 2012 statement on the evaluation and management of neurodevelopmental outcomes in children with congenital heart disease. It includes revised risk categories for developmental delay or disorder and an updated list of factors that increase neurodevelopmental risk in individuals with congenital heart disease according to current evidence, including genetic predisposition, fetal and perinatal factors, surgical and perioperative factors, socioeconomic disadvantage, and parental psychological distress. It also includes an updated algorithm for referral, evaluation, and management of individuals at high risk. Risk stratification of individuals with congenital heart disease with the updated categories and risk factors will identify a large and growing population of survivors at high risk for developmental delay or disorder and associated impacts across the life span. Critical next steps must include efforts to prevent and mitigate developmental delays and disorders. The goal of this scientific statement is to inform health care professionals caring for patients with congenital heart disease and other key stakeholders about the current state of knowledge of neurodevelopmental outcomes for individuals with congenital heart disease and best practices for neuroprotection, risk stratification, evaluation, and management.


Assuntos
American Heart Association , Cardiopatias Congênitas , Criança , Gravidez , Feminino , Estados Unidos , Humanos , Neuroproteção , Cardiopatias Congênitas/complicações , Fatores de Risco , Algoritmos
5.
Proc Natl Acad Sci U S A ; 119(19): e2013171119, 2022 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-35500110

RESUMO

Examining the relationship between tree diversity and ecosystem functioning has been a recent focus of forest ecology. Particular emphasis has been given to the impact of tree diversity on productivity and to its potential to mitigate negative global change effects; however, little attention has been paid to tree mortality. This is critical because both tree mortality and productivity underpin forest ecosystem dynamics and therefore forest carbon sequestration. Neglecting tree mortality leaves a large part of the picture undocumented. Here we show that increasingly diverse forest stands have increasingly high mortality probabilities. We found that the most species-rich stands in temperate biomes had mortality probabilities more than sevenfold higher than monospecific stands (∼0.6% year−1 in monospecific stands to 4.0% year−1 in the most species-rich stands) while in boreal stands increases were less pronounced but still significant (∼1.1% year−1 in monospecific stands to 1.8% year−1 in the most species-rich stands). Tree species richness was the third-most-important predictor of mortality in our models in temperate forests and the fifth-most-important predictor in boreal forests. Our results highlight that while the promotion of tree diversity undoubtedly has many positive effects on ecosystem functioning and the services that trees provide to humanity, it remains important to consider all aspects of forest dynamics in order to properly predict the implications of maintaining and promoting tree diversity.


Assuntos
Biodiversidade , Ecossistema , Canadá , Florestas , Estados Unidos
6.
Diabetologia ; 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39080044

RESUMO

AIMS/HYPOTHESIS: The aim of this work was to examine the impact of hypoglycaemia on daily functioning among adults with type 1 diabetes or insulin-treated type 2 diabetes, using the novel Hypo-METRICS app. METHODS: For 70 consecutive days, 594 adults (type 1 diabetes, n=274; type 2 diabetes, n=320) completed brief morning and evening Hypo-METRICS 'check-ins' about their experienced hypoglycaemia and daily functioning. Participants wore a blinded glucose sensor (i.e. data unavailable to the participants) for the study duration. Days and nights with or without person-reported hypoglycaemia (PRH) and/or sensor-detected hypoglycaemia (SDH) were compared using multilevel regression models. RESULTS: Participants submitted a mean ± SD of 86.3±12.5% morning and 90.8±10.7% evening check-ins. For both types of diabetes, SDH alone had no significant associations with the changes in daily functioning scores. However, daytime and night-time PRH (with or without SDH) were significantly associated with worsening of energy levels, mood, cognitive functioning, negative affect and fear of hypoglycaemia later that day or while asleep. In addition, night-time PRH (with or without SDH) was significantly associated with worsening of sleep quality (type 1 and type 2 diabetes) and memory (type 2 diabetes). Further, daytime PRH (with or without SDH), was associated with worsening of fear of hyperglycaemia while asleep (type 1 diabetes), memory (type 1 and type 2 diabetes) and social functioning (type 2 diabetes). CONCLUSIONS/INTERPRETATION: This prospective, real-world study reveals impact on several domains of daily functioning following PRH but not following SDH alone. These data suggest that the observed negative impact is mainly driven by subjective awareness of hypoglycaemia (i.e. PRH), through either symptoms or sensor alerts/readings and/or the need to take action to prevent or treat episodes.

7.
Ecol Lett ; 27(1): e14338, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38030225

RESUMO

Understanding the mechanisms underlying diversity-productivity relationships (DPRs) is crucial to mitigating the effects of forest biodiversity loss. Tree-tree interactions in diverse communities are fundamental in driving growth rates, potentially shaping the emergent DPRs, yet remain poorly explored. Here, using data from a large-scale forest biodiversity experiment in subtropical China, we demonstrated that changes in individual tree productivity were driven by species-specific pairwise interactions, with higher positive net pairwise interaction effects on trees in more diverse neighbourhoods. By perturbing the interactions strength from empirical data in simulations, we revealed that the positive differences between inter- and intra-specific interactions were the critical determinant for the emergence of positive DPRs. Surprisingly, the condition for positive DPRs corresponded to the condition for coexistence. Our results thus provide a novel insight into how pairwise tree interactions regulate DPRs, with implications for identifying the tree mixtures with maximized productivity to guide forest restoration and reforestation efforts.


Assuntos
Florestas , Árvores , Árvores/fisiologia , Biodiversidade , China , Ecossistema
8.
Ecol Lett ; 27(1): e14356, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38193391

RESUMO

The relationship between biodiversity and ecosystem function (BEF) captivates ecologists, but the factors responsible for the direction of this relationship remain unclear. While higher ecosystem functioning at higher biodiversity levels ('positive BEF') is not universal in nature, negative BEF relationships seem puzzlingly rare. Here, we develop a dynamical consumer-resource model inspired by microbial decomposer communities in pitcher plant leaves to investigate BEF. We manipulate microbial diversity via controlled colonization and measure their function as total ammonia production. We test how niche partitioning among bacteria and other ecological processes influence BEF in the leaves. We find that a negative BEF can emerge from reciprocal interspecific inhibition in ammonia production causing a negative complementarity effect, or from competitive hierarchies causing a negative selection effect. Absent these factors, a positive BEF was the typical outcome. Our findings provide a potential explanation for the rarity of negative BEF in empirical data.


Assuntos
Amônia , Ecossistema , Biodiversidade , Bactérias
9.
Ecol Lett ; 27(2): e14371, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38361471

RESUMO

It is widely acknowledged that biodiversity change is affecting human well-being by altering the supply of Nature's Contributions to People (NCP). Nevertheless, the role of individual species in this relationship remains obscure. In this article, we present a framework that combines the cascade model from ecosystem services research with network theory from community ecology. This allows us to quantitatively link NCP demanded by people to the networks of interacting species that underpin them. We show that this "network cascade" framework can reveal the number, identity and importance of the individual species that drive NCP and of the environmental conditions that support them. This information is highly valuable in demonstrating the importance of biodiversity in supporting human well-being and can help inform the management of biodiversity in social-ecological systems.


Assuntos
Biodiversidade , Ecossistema , Humanos , Ecologia
10.
Am J Epidemiol ; 193(1): 214-226, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-37667811

RESUMO

Postnatal mental health is often assessed using self-assessment questionnaires in epidemiologic research. Differences in response style, influenced by language, culture, and experience, may mean that the same response may not have the same meaning in different settings. These differences need to be identified and accounted for in cross-cultural comparisons. Here we describe the development and application of anchoring vignettes to investigate the cross-cultural functioning of the Edinburgh Postnatal Depression Scale (EPDS) in urban community samples in India (n = 549) and the United Kingdom (n = 828), alongside a UK calibration sample (n = 226). Participants completed the EPDS and anchoring vignettes when their children were 12-24 months old. In an unadjusted item-response theory model, UK mothers reported higher depressive symptoms than Indian mothers (d = 0.48, 95% confidence interval: 0.358, 0.599). Following adjustment for differences in response style, these positions were reversed (d = -0.25, 95% confidence interval: -0.391, -0.103). Response styles vary between India and the United Kingdom, indicating a need to take these differences into account when making cross-cultural comparisons. Anchoring vignettes offer a valid and feasible method for global data harmonization.


Assuntos
Depressão Pós-Parto , Feminino , Criança , Humanos , Lactente , Pré-Escolar , Depressão Pós-Parto/diagnóstico , Depressão Pós-Parto/psicologia , Mães/psicologia , Reino Unido , Inquéritos e Questionários , Saúde Mental , Escalas de Graduação Psiquiátrica
11.
Eur J Neurosci ; 59(8): 1877-1888, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37386749

RESUMO

The N400 event-related brain potential (ERP) semantic priming effect reflects greater activation of contextually related versus unrelated concepts in long-term semantic memory. Deficits in this measure have been found in persons with schizophrenia and those at clinical high risk (CHR) for this disorder. In CHR patients, we previously found that these deficits predict poorer social functional outcomes after 1 year. In the present study, we tested whether these deficits predicted greater psychosis-spectrum symptom severity and functional impairment over 2 years. We measured N400 semantic priming effects at baseline in CHR patients (n = 47) who viewed prime words each followed by a related/unrelated target word at stimulus-onset asynchronies (SOAs) of 300 or 750 ms. We measured psychosis-spectrum symptoms using the Structured Interview for Prodromal Symptoms and role and social functioning with the Global Functioning: Role and Social scales, at baseline, 1 (n = 29) and 2 years (n = 25). There was a significant interaction between the N400 semantic priming effect at the 300-ms SOA and time on GF:Role scores, indicating that, contrary to expectations, smaller baseline N400 semantic priming effects were associated with more improvement in role functioning from baseline to Year 1, but baseline N400 priming effects did not predict role functioning at Year 2. N400 priming effects were not significantly associated with different trajectories in psychosis-spectrum symptoms or social functioning. Thus, CHR patients' N400 semantic priming effects did not predict clinical outcomes over 2 years, suggesting that this ERP measure may have greater value as a state or short-term prognostic neurophysiological biomarker.


Assuntos
Potenciais Evocados , Transtornos Psicóticos , Humanos , Masculino , Feminino , Potenciais Evocados/fisiologia , Semântica , Eletroencefalografia , Estudos Longitudinais , Tempo de Reação/fisiologia , Encéfalo
12.
Clin Gastroenterol Hepatol ; 22(7): 1395-1403.e3, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38309495

RESUMO

BACKGROUND & AIMS: Cognitive-affective processes, including hypervigilance and symptom-specific anxiety, may contribute to chronic laryngeal symptoms and are potentially modifiable; however, a validated instrument to assess these constructs is lacking. The aims of this study were to develop and validate the Laryngeal Cognitive-Affective Tool (LCAT) instrument. METHODS: This 2-phase single-center prospective study enrolled participants from November 2021 to June 2023. In the initial phase 1:1 patient cognitive interviews and multidisciplinary team consensus were conducted to develop the LCAT. In the second phase asymptomatic and symptomatic participants completed a series of questionnaires to examine psychometric properties of the LCAT. RESULTS: A total of 268 participants were included: 8 in the initial phase and 260 in the validation phase (56 asymptomatic; 204 symptomatic). A 15-item LCAT was developed. In the validation phase, mean total LCAT and hypervigilance/anxiety subscores were significantly higher in symptomatic versus asymptomatic participants (P < .01). The LCAT had excellent internal consistency (α = 0.942) and split-half reliability (Guttman = 0.853). Using a median split, a score of 33 or greater was defined as elevated. CONCLUSIONS: The 15-item LCAT evaluates laryngeal hypervigilance and symptom-specific anxiety among patients with laryngeal symptoms. It has excellent reliability and construct validity. The LCAT highlights burdensome cognitive-affective processes that can accordingly help tailor treatments.


Assuntos
Psicometria , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Prospectivos , Inquéritos e Questionários , Idoso , Adulto , Psicometria/métodos , Reprodutibilidade dos Testes , Ansiedade/diagnóstico , Doenças da Laringe/diagnóstico , Doenças da Laringe/psicologia , Cognição/fisiologia
13.
BMC Med ; 22(1): 40, 2024 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-38281904

RESUMO

BACKGROUND: To date, almost no research on the psychosocial implications of albinism has been conducted in France and an exploration of albinism-related experiences could be beneficial, in order to better understand this condition. The aim of this study was to examine how French people with albinism and their parents live with and adapt to this condition in all the areas of their lives. METHODS: Semi-structured phone interviews were conducted with 9 parent-child dyads, each participating separately. Participants were recruited by convenience sampling, thanks to the combined efforts of a patient association (Genespoir) and professionals from the partner medical referral centers involved in the project. Dyads in which the individual with albinism had any comorbidity were excluded. The interviews were then transcribed and subjected to in-depth thematic analysis. Two codebooks were constructed in a mirrored process: one for people with albinism; the other for their parents. They were finally merged at the end of the coding step. RESULTS: Four main categories were identified: personal perceptions and social representations of albinism, difficulties and obstacles encountered by people with albinism, resources and facilitators, and the importance of parent-child functioning. The results indicated that experiences of stigmatization during childhood and adolescence are common and that people with albinism face challenges in adapting to certain obstacles related to their visual impairments (VI) (e.g., inability to drive a car; eye strain...). Parents emerged as one, if not as the main, source of support for people with albinism throughout their development. Although external support systems exist to assist them in various aspects of their lives, some of them primarily rely on their own personal resources to cope. CONCLUSIONS: This research highlights the importance of a systemic and transdisciplinary approach to make sure families receive the support that best meets their needs.


Assuntos
Albinismo , População Europeia , Apoio Familiar , Pais , Adolescente , Adulto , Humanos , Albinismo/epidemiologia , Albinismo/psicologia , População Europeia/psicologia , França , Pais/psicologia , Pesquisa Qualitativa , Estigma Social , Apoio Social
14.
Proc Biol Sci ; 291(2014): 20232622, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38196366

RESUMO

Terrestrial wetland ecosystems challenge biodiversity-ecosystem function theory, which generally links high species diversity to stable ecosystem functions. An open question in ecosystem ecology is whether assemblages of co-occurring peat mosses contribute to the stability of peatland ecosystem processes. We conducted a two-species (Sphagnum cuspidatum, Sphagnum medium) replacement series mesocosm experiment to evaluate the resistance, resilience, and recovery rates of net ecosystem CO2 exchange (NEE) under mild and deep water table drawdown. Our results show a positive effect of mild water table drawdown on NEE with no apparent role for peat moss mixture. Our study indicates that the carbon uptake capacity by peat moss mixtures is rather resilient to mild water table drawdown, but seriously affected by deeper drought conditions. Co-occurring peat moss species seem to enhance the resilience of the carbon uptake function (i.e. ability of NEE to return to pre-perturbation levels) of peat moss mixtures only slightly. These findings suggest that assemblages of co-occurring Sphagnum mosses do only marginally contribute to the stability of ecosystem functions in peatlands under drought conditions. Above all, our results highlight that predicted severe droughts can gravely affect the sink capacity of peatlands, with only a small extenuating role for peat moss mixtures.


Assuntos
Ecossistema , Sphagnopsida , Ecologia , Biodiversidade , Carbono
15.
New Phytol ; 243(4): 1312-1328, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38934095

RESUMO

Recent droughts have strongly impacted forest ecosystems and are projected to increase in frequency, intensity, and duration in the future together with continued warming. While evidence suggests that tree diversity can regulate drought impacts in natural forests, few studies examine whether mixed tree plantations are more resistant to the impacts of severe droughts. Using natural variations in leaf carbon (C) and nitrogen (N) isotopic ratios, that is δ13C and δ15N, as proxies for drought response, we analyzed the effects of tree species richness on the functional responses of tree plantations to the pan-European 2018 summer drought in seven European tree diversity experiments. We found that leaf δ13C decreased with increasing tree species richness, indicating less drought stress. This effect was not related to drought intensity, nor desiccation tolerance of the tree species. Leaf δ15N increased with drought intensity, indicating a shift toward more open N cycling as water availability diminishes. Additionally, drought intensity was observed to alter the influence of tree species richness on leaf δ15N from weakly negative under low drought intensity to weakly positive under high drought intensity. Overall, our findings suggest that dual leaf isotope analysis helps understand the interaction between drought, nutrients, and species richness.


Assuntos
Biodiversidade , Isótopos de Carbono , Secas , Isótopos de Nitrogênio , Folhas de Planta , Estações do Ano , Árvores , Folhas de Planta/fisiologia , Árvores/fisiologia , Isótopos de Carbono/análise , Europa (Continente) , Especificidade da Espécie
16.
New Phytol ; 243(3): 1205-1219, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38855965

RESUMO

Decades of studies have demonstrated links between biodiversity and ecosystem functioning, yet the generality of the relationships and the underlying mechanisms remain unclear, especially for forest ecosystems. Using 11 tree-diversity experiments, we tested tree species richness-community productivity relationships and the role of arbuscular (AM) or ectomycorrhizal (ECM) fungal-associated tree species in these relationships. Tree species richness had a positive effect on community productivity across experiments, modified by the diversity of tree mycorrhizal associations. In communities with both AM and ECM trees, species richness showed positive effects on community productivity, which could have resulted from complementarity between AM and ECM trees. Moreover, both AM and ECM trees were more productive in mixed communities with both AM and ECM trees than in communities assembled by their own mycorrhizal type of trees. In communities containing only ECM trees, species richness had a significant positive effect on productivity, whereas species richness did not show any significant effects on productivity in communities containing only AM trees. Our study provides novel explanations for variations in diversity-productivity relationships by suggesting that tree-mycorrhiza interactions can shape productivity in mixed-species forest ecosystems.


Assuntos
Biodiversidade , Micorrizas , Árvores , Micorrizas/fisiologia , Árvores/microbiologia , Especificidade da Espécie
17.
Mol Ecol ; 33(9): e17331, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38533629

RESUMO

Marine sediments cover 70% of the Earth's surface, and harbour diverse bacterial communities critical for marine biogeochemical processes, which affect climate change, biodiversity and ecosystem functioning. Nematodes, the most abundant and species-rich metazoan organisms in marine sediments, in turn, affect benthic bacterial communities and bacterial-mediated ecological processes, but the underlying mechanisms by which they affect biogeochemical cycles remain poorly understood. Here, we demonstrate using a metatranscriptomic approach that nematodes alter the taxonomic and functional profiles of benthic bacterial communities. We found particularly strong stimulation of nitrogen-fixing and methane-oxidizing bacteria in the presence of nematodes, as well as increased functional activity associated with methane metabolism and degradation of various carbon compounds. This study provides empirical evidence that the presence of nematodes results in taxonomic and functional shifts in active bacterial communities, indicating that nematodes may play an important role in benthic ecosystem processes.


Assuntos
Bactérias , Ecossistema , Sedimentos Geológicos , Nematoides , Animais , Nematoides/microbiologia , Nematoides/genética , Bactérias/genética , Bactérias/classificação , Sedimentos Geológicos/microbiologia , Biodiversidade , Transcriptoma , Microbiota/genética , Metano/metabolismo
18.
Hum Reprod ; 39(4): 779-783, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38373211

RESUMO

STUDY QUESTION: What are parents' perceptions of their relationships with and the psychosocial adjustments of their children who are born via embryo donation? SUMMARY ANSWER: Families created through embryo donation have well-adjusted parent-child relationships and reassuring child psychosocial outcomes. WHAT IS KNOWN ALREADY: Embryo donation is an effective and growing form of third-party reproduction, but there is limited research in this field. Prior studies suggest that families created through gamete donation function well regarding parent-child relationship quality and child behavioral and socioemotional adjustment. STUDY DESIGN, SIZE, DURATION: This is a cross-sectional survey study with 187 total participants. PARTICIPANTS/MATERIALS, SETTING, METHODS: Parents of children born via embryo donation were recruited nationally by contacting all embryo donation programs registered with the Society for Assisted Reproductive Technology Clinic Outcome Reporting System (SART CORS) as well as medically directed embryo donation or 'embryo adoption' centers. Participants completed three online Qualtrics questionnaires. The first was a survey including 33 questions on demographics, the procurement process, and self-reported obstetric outcomes. Participants also completed two standardized measures assessing children's behavior and parents' adjustment to parenthood: the Strengths and Difficulties Questionnaire (SDQ) and the Parental Acceptance-Rejection Questionnaire (PARQ). Scoring of the SDQ and PARQ was totaled and compared to standardized values (SDQ) or previously published results on other forms of gamete donation (PARQ), such as oocyte donation and sperm donation. MAIN RESULTS AND THE ROLE OF CHANCE: On the SDQ (n = 46), the average total difficulties scores by age were: 8.2 ± 0.98 for ages 2-4, 7.6 ± 0.93 for ages 5-10, and 3.5 ± 0.77 for ages 11-17; this is compared to the normal reported range of 0-13, which indicates that clinically significant psychosocial problems are unlikely. Across all ages and individual categories (emotional symptoms, conduct problem, hyperactivity, peer problem, prosocial), scores on the SDQ were within the normal ranges. The average PARQ score (n = 70) for all respondents was 27.5 ± 1.18 (range: 24-96), suggesting perceived parental acceptance. LIMITATIONS, REASONS FOR CAUTION: Because this study was cross-sectional, it could not capture familial relationships over time. This survey-based study design allows for potential selection bias (parents of well-adjusted children may be more likely to participate). Additionally, the overall sample size is relatively small; however, it remains one of the largest published to date. Another significant limitation to this study is the lack of generalizability: most participants were recruited from private, faith-based, embryo donation programs who are demographically similar. WIDER IMPLICATIONS OF THE FINDINGS: Though embryo donation is an established form of third-party reproduction, it is significantly less robustly studied compared to other forms of gamete donation (oocyte or sperm donation). This study provides a larger data set with a more expanded age range of children compared to the limited number of previously published studies. Furthermore, these findings indicate a high parental disclosure rate with respect to the use of embryo donation which contrasts previous findings. STUDY FUNDING/COMPETING INTEREST(S): No external funding source was utilized for the completion of this study. No conflicts are disclosed. TRIAL REGISTRATION NUMBER: N/A.


Assuntos
Destinação do Embrião , Sêmen , Feminino , Gravidez , Humanos , Masculino , Estudos Transversais , Técnicas de Reprodução Assistida/psicologia , Pais/psicologia
19.
Glob Chang Biol ; 30(3): e17235, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38497525

RESUMO

The accelerating pace of climate change has led to unprecedented shifts in surface temperature and precipitation patterns worldwide, with African savannas being among the most vulnerable regions. Understanding the impacts of these extreme changes on ecosystem health, functioning and stability is crucial. This paper focuses on the detection of breakpoints, indicative of shifts in ecosystem functioning, while also determining relevant ecosystem characteristics and climatic drivers that increase susceptibility to these shifts within the semi-arid to arid savanna biome. Utilising a remote sensing change detection approach and rain use efficiency (RaUE) as a proxy for ecosystem functioning, spatial and temporal patterns of breakpoints in the savanna biome were identified. We then employed a novel combination of survival analysis and remote sensing time series analysis to compare ecosystem characteristics and climatic drivers in areas experiencing breakpoints versus areas with stable ecosystem functioning. Key ecosystem factors increasing savanna breakpoint susceptibility were identified, namely higher soil sand content, flatter terrain and a cooler long-term mean temperature during the wet summer season. Moreover, the primary driver of changes in ecosystem functioning in arid savannas, as opposed to wetter tropical savannas, was found to be the increased frequency and severity of rainfall events, rather than drought pressures. This research highlights the importance of incorporating wetness severity metrics alongside drought metrics to comprehensively understand climate-ecosystem interactions leading to abrupt shifts in ecosystem functioning in arid biomes. The findings also emphasise the need to consider the underlying ecosystem characteristics, including soil, topography and vegetation composition, in assessing ecosystem responses to climate change. While this research primarily concentrated on the southern African savanna as a case study, the methodological robustness of this approach enables its application to diverse arid and semi-arid biomes for the assessment of climate-ecosystem interactions that contribute to abrupt shifts.


Assuntos
Ecossistema , Pradaria , Chuva , Estações do Ano , Solo
20.
Glob Chang Biol ; 30(3): e17225, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38462708

RESUMO

It is well known that biodiversity positively affects ecosystem functioning, leading to enhanced ecosystem stability. However, this knowledge is mainly based on analyses using single ecosystem functions, while studies focusing on the stability of ecosystem multifunctionality (EMF) are rare. Taking advantage of a long-term grassland biodiversity experiment, we studied the effect of plant diversity (1-60 species) on EMF over 5 years, its temporal stability, as well as multifunctional resistance and resilience to a 2-year drought event. Using split-plot treatments, we further tested whether a shared history of plants and soil influences the studied relationships. We calculated EMF based on functions related to plants and higher-trophic levels. Plant diversity enhanced EMF in all studied years, and this effect strengthened over the study period. Moreover, plant diversity increased the temporal stability of EMF and fostered resistance to reoccurring drought events. Old plant communities with shared plant and soil history showed a stronger plant diversity-multifunctionality relationship and higher temporal stability of EMF than younger communities without shared histories. Our results highlight the importance of old and biodiverse plant communities for EMF and its stability to extreme climate events in a world increasingly threatened by global change.


Assuntos
Ecossistema , Pradaria , Biodiversidade , Plantas , Solo
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