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The sustainability of marine communities is critical for supporting many biophysical processes that provide ecosystem services that promote human well-being. It is expected that anthropogenic disturbances such as climate change and human activities will tend to create less energetically-efficient ecosystems that support less biomass per unit energy flow. It is debated, however, whether this expected development should translate into bottom-heavy (with small basal species being the most abundant) or top-heavy communities (where more biomass is supported at higher trophic levels with species having larger body sizes). Here, we combine ecological theory and empirical data to demonstrate that full marine protection promotes shifts towards top-heavy energetically-efficient structures in marine communities. First, we use metabolic scaling theory to show that protected communities are expected to display stronger top-heavy structures than disturbed communities. Similarly, we show theoretically that communities with high energy transfer efficiency display stronger top-heavy structures than communities with low transfer efficiency. Next, we use empirical structures observed within fully protected marine areas compared to disturbed areas that vary in stress from thermal events and adjacent human activity. Using a nonparametric causal-inference analysis, we find a strong, positive, causal effect between full marine protection and stronger top-heavy structures. Our work corroborates ecological theory on community development and provides a quantitative framework to study the potential restorative effects of different candidate strategies on protected areas.
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Mudança Climática , Ecossistema , Humanos , Biomassa , Tamanho CorporalRESUMO
BACKGROUND: The World Health Organization recommends to wait at least 6 months after miscarriage and induced abortion before becoming pregnant again to avoid complications in the next pregnancy, although the evidence-based underlying this recommendation is scarce. We aimed to investigate the risk of adverse pregnancy outcomes-preterm birth (PTB), spontaneous PTB, small for gestational age (SGA) birth, large for gestational age (LGA) birth, preeclampsia, and gestational diabetes mellitus (GDM)-by interpregnancy interval (IPI) for births following a previous miscarriage or induced abortion. METHODS AND FINDINGS: We conducted a cohort study using a total of 49,058 births following a previous miscarriage and 23,707 births following a previous induced abortion in Norway between 2008 and 2016. We modeled the relationship between IPI and 6 adverse pregnancy outcomes separately for births after miscarriages and births after induced abortions. We used log-binomial regression to estimate unadjusted and adjusted relative risk (aRR) and 95% confidence intervals (CIs). In the adjusted model, we included maternal age, gravidity, and year of birth measured at the time of the index (after interval) births. In a sensitivity analysis, we further adjusted for smoking during pregnancy and prepregnancy body mass index. Compared to births with an IPI of 6 to 11 months after miscarriages (10.1%), there were lower risks of SGA births among births with an IPI of <3 months (8.6%) (aRR 0.85, 95% CI: 0.79, 0.92, p < 0.01) and 3 to 5 months (9.0%) (aRR 0.90, 95% CI: 0.83, 0.97, p = 0.01). An IPI of <3 months after a miscarriage (3.3%) was also associated with lower risk of GDM (aRR 0.84, 95% CI: 0.75, 0.96, p = 0.01) as compared to an IPI of 6 to 11 months (4.5%). For births following an induced abortion, an IPI <3 months (11.5%) was associated with a nonsignificant but increased risk of SGA (aRR 1.16, 95% CI: 0.99, 1.36, p = 0.07) as compared to an IPI of 6 to 11 months (10.0%), while the risk of LGA was lower among those with an IPI 3 to 5 months (8.0%) (aRR 0.84, 95% CI: 0.72, 0.98, p = 0.03) compared to an IPI of 6 to 11 months (9.4%). There was no observed association between adverse pregnancy outcomes with an IPI >12 months after either a miscarriage or induced abortion (p > 0.05), with the exception of an increased risk of GDM among women with an IPI of 12 to 17 months (5.8%) (aRR 1.20, 95% CI: 1.02, 1.40, p = 0.02), 18 to 23 months (6.2%) (aRR 1.24, 95% CI: 1.02, 1.50, p = 0.03), and ≥24 months (6.4%) (aRR 1.14, 95% CI: 0.97, 1.34, p = 0.10) compared to an IPI of 6 to 11 months (4.5%) after a miscarriage. Inherent to retrospective registry-based studies, we did not have information on potential confounders such as pregnancy intention and health-seeking bahaviour. Furthermore, we only had information on miscarriages that resulted in contact with the healthcare system. CONCLUSIONS: Our study suggests that conceiving within 3 months after a miscarriage or an induced abortion is not associated with increased risks of adverse pregnancy outcomes. In combination with previous research, these results suggest that women could attempt pregnancy soon after a previous miscarriage or induced abortion without increasing perinatal health risks.
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Aborto Induzido , Aborto Espontâneo , Diabetes Gestacional , Doenças do Recém-Nascido , Nascimento Prematuro , Gravidez , Recém-Nascido , Feminino , Humanos , Resultado da Gravidez/epidemiologia , Aborto Espontâneo/epidemiologia , Aborto Espontâneo/etiologia , Intervalo entre Nascimentos , Estudos de Coortes , Estudos Retrospectivos , Nascimento Prematuro/epidemiologia , Nascimento Prematuro/etiologia , Retardo do Crescimento FetalRESUMO
INTRODUCTION: The benefit of smoking cessation in reducing the risk of preterm birth is well established. Relatively less well understood is the prevalence of smoking cessation maintenance at the next pregnancy and the associated preterm risk reduction. The aim of this study was to estimate the prevalence of maintenance of smoking cessation at second pregnancy and the associated relative risk of preterm birth. METHODS: This was a longitudinal study with retrospectively obtained records of births to multiparous women who smoked in the pregnancy of their first birth in New South Wales, 1994-2016 (N = 63 195 mothers). Relative risks (RR) of preterm birth of the second child were estimated for smoking cessation with adjustment for final gestational age of the first birth, maternal age at the first birth, change in socioeconomic disadvantage between the first and second pregnancy, interpregnancy interval, and calendar time. RESULTS: Approximately 34% (N = 21 540) of women who smoked during their first pregnancy did not smoke in the second pregnancy. Smoking cessation among women who smoked at first pregnancy was associated with a 26% (95% CI: 21%, 31%) decrease in risk of preterm birth at a second pregnancy. CONCLUSION: Despite smoking during the first pregnancy, smoking cessation was achieved and maintained by more than one-third of women in their second pregnancy with encouraging levels of preterm risk reduction. It is well-established that the period after birth provides an opportunity to reduce smoking-related morbidity for both the mother and neonate. Our results indicate that this period also offers an opportunity to prevent morbidity of future pregnancy. IMPLICATIONS: A considerable amount of research has been undertaken on the effects of smoking during pregnancy on birth outcomes, the influence of postpartum smoking on the health of the mother and newborn child, and postpartum smoking cessation. However, follow-up of women after giving birth does not tend to be long enough to observe smoking and outcomes of subsequent pregnancies. We show that smoking cessation in the subsequent pregnancy is achievable by a large proportion of women despite smoking in their first pregnancy, which translates to clear reductions in risk of preterm birth in the subsequent pregnancy.
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Nascimento Prematuro , Abandono do Hábito de Fumar , Feminino , Humanos , Recém-Nascido , Estudos Longitudinais , Gravidez , Nascimento Prematuro/epidemiologia , Estudos Retrospectivos , Fatores de Risco , Fumaça , Fumar/epidemiologiaRESUMO
BACKGROUND/AIMS: Given the extent of osteoporosis in people with Duchenne muscular dystrophy treated with glucocorticoids and the limited evidence of bone-protective therapies, clinical trials are needed. We conducted surveys to obtain the opinion of young people with Duchenne muscular dystrophy, parents/guardians and neuromuscular clinicians on the feasibility of osteoporosis clinical trials in this population. METHODS: Online surveys were sent to three groups: (a) people with a confirmed diagnosis of Duchenne muscular dystrophy (≥14 years), (b) parents and guardians and (c) neuromuscular clinicians in the UK NorthStar Clinical Network. Surveys (a) and (b) were distributed via the UK Duchenne muscular dystrophy Registry. RESULTS: Survey respondents included 52 people with Duchenne muscular dystrophy with a median age of 17 years (range: 14, 40) and 183 parents/guardians. Fourteen out of 23 (61%) NorthStar centres responded. Of the 52 people with Duchenne muscular dystrophy, 13 (25%) were very concerned about their bone health and 21 (40%) were slightly concerned. Of the 183 parents/guardians, 75 (41%) were very concerned about their son's bone health and 90 (49%) were slightly concerned. Fractures and quality of life were the top two main outcome measures identified by people with Duchenne muscular dystrophy. Fractures and bone density were the top two main outcome measures identified by parents/guardians and neuromuscular clinicians. Thirty percent of people with Duchenne muscular dystrophy and 40% of parents/guardians would not take part if an osteoporosis trial involved a placebo that was administered parenterally. Only 2 of the 14 NorthStar centres (14%) would enrol people with Duchenne muscular dystrophy if a parenteral placebo was used in an osteoporosis trial in Duchenne muscular dystrophy. CONCLUSION: There is great awareness of bone health and the need for bone-protective trials among people with Duchenne muscular dystrophy and their carers. However, a proportion of people with Duchenne muscular dystrophy and parents are reluctant to participate in a placebo-controlled osteoporosis trial that included a parenteral therapy. A larger proportion of health care experts are unwilling to enrol their patients in such a trial. Our finding is relevant for the design of bone-protective studies in Duchenne muscular dystrophy.
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Ensaios Clínicos como Assunto , Distrofia Muscular de Duchenne , Osteoporose , Adolescente , Estudos de Viabilidade , Humanos , Distrofia Muscular de Duchenne/tratamento farmacológico , Osteoporose/tratamento farmacológico , Participação do Paciente , Placebos , Qualidade de Vida , Inquéritos e QuestionáriosRESUMO
Routine screening of the spine for vertebral fracture is recommended in the recent international standards of care for boys with Duchenne muscular dystrophy (DMD). Recent international consensus endorses the use of dual energy absorptiometry vertebral fracture assessment for identification of vertebral fractures in children, which could be used instead of spine radiographs. This study aims to evaluate the inter-observer agreement for vertebral fracture classification in boys with DMD, and the impact on clinical management. Dual energy absorptiometry vertebral fracture assessment and morphometric analysis in 39 boys was performed by a reader with no prior experience (R1) and 2 readers with experience (R2 and R3). Inter-observer concordance of vertebral fracture grading comparing R1 with R2 and R3 was substantial (Kappa 0.66, 95% CI 0.56, 0.76). Concordance between R2 and R3 was almost perfect (Kappa 0.93, 95% CI 0.89, 0.97) which did not lead to differences in clinical management. Grading by R1 in comparison to R2 and R3 would have led to change in management of 5/39 boys (13%), according to recent standards of care guidance. Structured education programme on identification of vertebral fractures should be explored to ensure consistency of reporting of this important health outcome measure in DMD.
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Distrofia Muscular de Duchenne , Fraturas da Coluna Vertebral , Absorciometria de Fóton , Criança , Humanos , Masculino , Distrofia Muscular de Duchenne/complicações , Distrofia Muscular de Duchenne/diagnóstico por imagem , Radiografia , Fraturas da Coluna Vertebral/diagnóstico por imagem , Fraturas da Coluna Vertebral/etiologia , Coluna VertebralRESUMO
We aimed to compare body segment and bone lengths in glucocorticoid-treated boys with Duchenne muscular dystrophy (DMD) with healthy controls using dual-energy absorptiometry (DXA) images. Total height (Ht), sitting height (SH), leg length (LL) and bone lengths (femur, tibia) in boys with DMD and age-matched control boys were measured using DXA. Thirty boys with DMD (median age 10.0 years (6.1, 16.8)) were compared with 30 controls. SH in DMD was 3.3 cm lower (95% CI - 6.1, - 0.66; p = 0.016). LL in DMD was 7.3 cm lower (95% CI - 11.2, - 3.4; p < 0.0001). SH:LL of boys with DMD was higher by 0.08 (95% CI 0.04, 0.12; p < 0.0001). Femur length in DMD was 2.4 cm lower (95% CI - 4.6, - 0.12; p = 0.04), whereas tibial length in DMD was 4.8 cm lower (95% CI - 6.7, - 2.9; p < 0.0001). SH:LL was not associated with duration of glucocorticoid use (SH:LL ß = 0.003, 95% CI - 0.01 to 0.002, p = 0.72).Conclusion: Glucocorticoid-treated boys with DMD exhibit skeletal disproportion with relatively shorter leg length and more marked reduction of distal long bones. As glucocorticoid excess is not associated with such disproportion, our findings raise the possibility of an intrinsic disorder of growth in DMD. What is Known ⢠Severe growth impairment and short stature are commonly observed in boys with Duchenne muscular dystrophy (DMD), especially those treated with long-term glucocorticoids (GC). ⢠In other groups of children with chronic conditions and/or disorders of puberty, skeletal disproportion with lower spinal length has been reported. What is New ⢠Growth impairment in GC-treated boys with DMD was associated with skeletal disproportion in relation to age, with lower limbs and distal long bones affected to a greater degree.
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Tamanho Corporal , Osso e Ossos/anatomia & histologia , Glucocorticoides/uso terapêutico , Transtornos do Crescimento/etiologia , Distrofia Muscular de Duchenne/tratamento farmacológico , Absorciometria de Fóton , Adolescente , Estudos de Casos e Controles , Criança , Estudos Transversais , Transtornos do Crescimento/diagnóstico , Humanos , Modelos Lineares , Masculino , Distrofia Muscular de Duchenne/fisiopatologia , Estudos ProspectivosRESUMO
OBJECTIVE: To investigate the association of policy, systems and environmental factors with improvement in household food security among low-income Indiana households with children after a Supplemental Nutrition Assistance Program-Education (SNAP-Ed) direct nutrition education intervention. DESIGN: Household food security scores measured by the eighteen-item US Household Food Security Survey Module in a longitudinal randomized and controlled SNAP-Ed intervention study conducted from August 2013 to April 2015 were the response variable. Metrics to quantify environmental factors including classification of urban or rural county status; the number of SNAP-authorized stores, food pantries and recreational facilities; average fair market housing rental price; and natural amenity rank were collected from government websites and data sets covering the years 2012-2016 and used as covariates in mixed multiple linear regression modelling. SETTING: Thirty-seven Indiana counties, USA, 2012-2016. SUBJECTS: SNAP-Ed eligible adults from households with children (n 328). RESULTS: None of the environmental factors investigated were significantly associated with changes in household food security in this exploratory study. CONCLUSIONS: SNAP-Ed improves food security regardless of urban or rural location or the environmental factors investigated. Expansion of SNAP-Ed in rural areas may support food access among the low-income population and reduce the prevalence of food insecurity in rural compared with urban areas. Further investigation into policy, systems and environmental factors of the Social Ecological Model are warranted to better understand their relationship with direct SNAP-Ed and their impact on diet-related behaviours and food security.
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Dieta , Assistência Alimentar , Abastecimento de Alimentos , Pobreza , Avaliação de Programas e Projetos de Saúde , População Rural , População Urbana , Adolescente , Adulto , Criança , Estudos Transversais , Características da Família , Feminino , Educação em Saúde , Habitação , Humanos , Indiana , Estilo de Vida , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Inquéritos Nutricionais , Meio Social , Adulto JovemRESUMO
Comparative research on food web structure has revealed generalities in trophic organization, produced simple models, and allowed assessment of robustness to species loss. These studies have mostly focused on free-living species. Recent research has suggested that inclusion of parasites alters structure. We assess whether such changes in network structure result from unique roles and traits of parasites or from changes to diversity and complexity. We analyzed seven highly resolved food webs that include metazoan parasite data. Our analyses show that adding parasites usually increases link density and connectance (simple measures of complexity), particularly when including concomitant links (links from predators to parasites of their prey). However, we clarify prior claims that parasites "dominate" food web links. Although parasites can be involved in a majority of links, in most cases classic predation links outnumber classic parasitism links. Regarding network structure, observed changes in degree distributions, 14 commonly studied metrics, and link probabilities are consistent with scale-dependent changes in structure associated with changes in diversity and complexity. Parasite and free-living species thus have similar effects on these aspects of structure. However, two changes point to unique roles of parasites. First, adding parasites and concomitant links strongly alters the frequency of most motifs of interactions among three taxa, reflecting parasites' roles as resources for predators of their hosts, driven by trophic intimacy with their hosts. Second, compared to free-living consumers, many parasites' feeding niches appear broader and less contiguous, which may reflect complex life cycles and small body sizes. This study provides new insights about generic versus unique impacts of parasites on food web structure, extends the generality of food web theory, gives a more rigorous framework for assessing the impact of any species on trophic organization, identifies limitations of current food web models, and provides direction for future structural and dynamical models.
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Biodiversidade , Cadeia Alimentar , Parasitos/fisiologia , Animais , Modelos Lineares , Modelos Biológicos , Probabilidade , Especificidade da EspécieRESUMO
Generalities of food web structure have been identified for extant ecosystems. However, the trophic organization of ancient ecosystems is unresolved, as prior studies of fossil webs have been limited by low-resolution, high-uncertainty data. We compiled highly resolved, well-documented feeding interaction data for 700 taxa from the 48 million-year-old latest early Eocene Messel Shale, which contains a species assemblage that developed after an interval of protracted environmental and biotal change during and following the end-Cretaceous extinction. We compared the network structure of Messel lake and forest food webs to extant webs using analyses that account for scale dependence of structure with diversity and complexity. The Messel lake web, with 94 taxa, displays unambiguous similarities in structure to extant webs. While the Messel forest web, with 630 taxa, displays differences compared to extant webs, they appear to result from high diversity and resolution of insect-plant interactions, rather than substantive differences in structure. The evidence presented here suggests that modern trophic organization developed along with the modern Messel biota during an 18 Myr interval of dramatic post-extinction change. Our study also has methodological implications, as the Messel forest web analysis highlights limitations of current food web data and models.
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Cadeia Alimentar , Fósseis , Animais , Biota , Ecossistema , Florestas , Lagos , Modelos TeóricosRESUMO
Background: Delayed puberty is thought to be common in boys with Duchenne muscular dystrophy (DMD) treated with long term oral glucocorticoid. This study aims to report the frequency of delayed puberty in DMD from examination by a paediatric endocrinologist alongside detailed endocrine investigations. Methods: All boys with DMD aged at least 14 years in January 2022 known to the paediatric neuromuscular service (2016-2022) were included in this study. Delayed puberty was defined based on testicular volume and genital staging in comparison to published puberty nomogram. Results: Twenty-four out of 37 boys (65%) had evidence of delayed puberty, 23/24 (96%) of those with delayed puberty were on glucocorticoid therapy all of whom were on daily glucocorticoid. On the other hand, 7/13 (54%) of those with normal timing of puberty were on glucocorticoid; 2/7 (29%) were on the intermittent regimen. Of those who were on daily glucocorticoid therapy at the time of assessment of puberty, 23/28 (82%) had evidence of delayed puberty. In boys with delayed puberty, endocrine investigations showed low luteinizing hormone (LH) with undetectable testosterone levels, a pre-pubertal response with lutenizing hormone releasing hormone test and sub-optimal testosterone levels with prolonged human chorionic gonadotropin stimulation. Conclusion: The frequency of delayed puberty in boys with DMD was 65%. Eighty-two percent of adolescent boys with DMD on daily glucocorticoid had evidence of delayed puberty. Biochemical investigations point to functional central hypogonadism in these adolescents. Our data supports the routine monitoring of puberty in boys with DMD.
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BACKGROUND: It is important to explore factors that may hinder early childhood development in AEDC Emotional Maturity and Social Competence domains as these underpin the foundation for health, well-being, and productivity over the life course. No previous study has examined whether, or to what extent, preeclampsia increases the risk of developmental vulnerability in social and emotional domains in early childhood. METHODS: We conducted a retrospective population-based cohort study on the association between preeclampsia and childhood developmental vulnerability in emotional maturity and social competence domains in children born in Western Australia in 2009, 2012 and 2015. We obtained records of births, developmental anomalies, midwives notifications and hospitalisations. These data were linked to the Australian Early Development Census (AEDC), from which developmental vulnerability in emotional maturity and social competence domains at a median age of 5 years was ascertained. Causal relative risks (RR) were estimated with doubly robust estimation. RESULTS: A total of 64,391 mother-offspring pairs were included in the final analysis. For the whole cohort, approximately 25 % and 23 % of children were classified as developmentally vulnerable or at-risk on AEDC emotional maturity and social competence domains, respectively. Approximately 2.8 % of children were exposed in utero to preeclampsia. Children exposed to preeclampsia were more likely to be classified as developmentally vulnerable or at-risk on the emotional maturity (RR = 1.19, 95%CI:1.11-1.28) and social competence domains (RR = 1.22, 95 % CI:1.13-1.31). CONCLUSION: Children exposed to pre-eclampsia in utero were more likely to be developmentally vulnerable in emotional maturity and social competence domains in this cohort. Our findings provide new insights into the harmful effect of preeclampsia on childhood developmental vulnerability.
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Pré-Eclâmpsia , Criança , Gravidez , Feminino , Humanos , Pré-Escolar , Austrália Ocidental/epidemiologia , Austrália/epidemiologia , Pré-Eclâmpsia/epidemiologia , Estudos Retrospectivos , Estudos de Coortes , Desenvolvimento InfantilRESUMO
BACKGROUND: Multiple systematic reviews on prenatal ambient temperature and adverse birth outcomes exist, but the overall epidemiological evidence and the appropriate metric for thermal stress remain unclear. An umbrella review was performed to summarise and appraise the evidence with recommendations. METHODS: Systematic reviews and meta-analyses on the associations between ambient temperature and adverse birth outcomes (preterm birth, stillbirth, birth weight, low birth weight, and small for gestational age) up to December 20, 2023, were synthesised according to a published protocol. Databases PubMed, CINAHL, Scopus, MEDLINE/Ovid, EMBASE/Ovid, Web of Science Core Collection, systematic reviews repositories, electronic grey literature, and references were searched. Risk of bias was assessed using Joanna Briggs Institute's critical appraisal tool. RESULTS: Eleven systematic reviews, including two meta-analyses, were included. This comprised 90 distinct observational studies that employed multiple temperature assessment metrics with a very high overlap of primary studies. Primary studies were mostly from the United States while both Africa and South Asia contributed only three studies. A majority (7 out of 11) of the systematic reviews were rated as moderate risk of bias. All systematic reviews indicated that maternal exposures to both extremely high and low temperatures, particularly during late gestation are associated with increased risks of preterm birth, stillbirth, and reduced fetal growth. However, due to great differences in the exposure assessments, high heterogeneity, imprecision, and methodological limitations of the included systematic reviews, the overall epidemiological evidence was classified as probable evidence of causation. No study assessed biothermal metrics for thermal stress. CONCLUSIONS: Despite the notable methodological differences, prenatal exposure to extreme ambient temperatures, particularly during late pregnancy, was associated with adverse birth outcomes. Adhering to the appropriate systematic review guidelines for environmental health research, incorporating biothermal metrics into exposure assessment, evidence from broader geodemographic settings, and interventions are recommended in future studies.
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Exposição Materna , Nascimento Prematuro , Feminino , Humanos , Recém-Nascido , Gravidez , Peso ao Nascer , Recém-Nascido de Baixo Peso , Exposição Materna/estatística & dados numéricos , Metanálise como Assunto , Resultado da Gravidez/epidemiologia , Nascimento Prematuro/epidemiologia , Natimorto/epidemiologia , Revisões Sistemáticas como Assunto , TemperaturaRESUMO
Background: Spontaneous and induced abortions are common outcomes of pregnancy. There is inconsistent evidence of an association between early pregnancy loss and subsequent diabetic and hypertensive disorders in women. This systematic review and meta-analysis evaluated evidence on the risk of the subsequent development of pregnancy and non-pregnancy related diabetic and hypertensive disorders in women who experienced an early pregnancy loss. Methods: Systematic searches were conducted in seven electronic databases (CINAHL Plus, Ovid/EMBASE, Ovid/MEDLINE, ProQuest, PubMed, Scopus, and Web of Science) from inception to 22nd December 2023. Studies were included if they reported an exposure of spontaneous abortion (SAB), induced abortion (IA) or recurrent pregnancy loss (RPL) with an outcome of gestational diabetes mellitus, pre-eclampsia, gestational hypertension, and non-pregnancy related diabetic and hypertensive disorders. Risk of bias was assessed using Risk of Bias Instrument for Non-Randomized Studies of Exposures (ROBINS-E). Random effects meta-analysis was used to pool odds of developing diabetic and hypertensive disorders following an early pregnancy loss. This study is registered with PROSPERO (CRD42022327689). Findings: Of 20,176 records, 60 unique articles were identified for full-text review and 52 met the inclusion criteria, representing a total population of 4,132,895 women from 22 countries. Thirty-five studies were suitable for meta-analysis, resulting in a pooled odds ratio (OR) of 1.44 (95% confidence interval (CI) 1.23-1.68) for gestational diabetes mellitus following a prior SAB and a pooled OR of 1.06 (95% CI 0.90-1.26) for pre-eclampsia following a prior SAB. RPL increased the odds of developing pre-eclampsia (OR 1.37 95% CI 1.05-1.79). There was no association between IA and diabetic and hypertensive disorders. Interpretation: A prior SAB was associated with increased odds of gestational diabetes mellitus, but not pre-eclampsia. However, women who experienced RPL had an increased risk of subsequent pre-eclampsia. Future research is required to establish evidence for an association between early pregnancy loss with non-pregnancy related diabetic and hypertensive disorders. Funding: National Health and Medical Research Council.
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Plants and their insect herbivores have been a dominant component of the terrestrial ecological landscape for the past 410 million years and feature intricate evolutionary patterns and co-dependencies. A complex systems perspective allows for both detailed resolution of these evolutionary relationships as well as comparison and synthesis across systems. Using proxy data of insect herbivore damage (denoted by the damage type or DT) preserved on fossil leaves, functional bipartite network representations provide insights into how plant-insect associations depend on geological time, paleogeographical space, and environmental variables such as temperature and precipitation. However, the metrics measured from such networks are prone to sampling bias. Such sensitivity is of special concern for plant-DT association networks in paleontological settings where sampling effort is often severely limited. Here, we explore the sensitivity of functional bipartite network metrics to sampling intensity and identify sampling thresholds above which metrics appear robust to sampling effort. Across a broad range of sampling efforts, we find network metrics to be less affected by sampling bias and/or sample size than richness metrics, which are routinely used in studies of fossil plant-DT interactions. These results provide reassurance that cross-comparisons of plant-DT networks offer insights into network structure and function and support their widespread use in paleoecology. Moreover, these findings suggest novel opportunities for using plant-DT networks in neontological terrestrial ecology to understand functional aspects of insect herbivory across geological time, environmental perturbations, and geographic space.
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Benchmarking , Insetos , Animais , Viés de Seleção , Plantas , Folhas de Planta , HerbivoriaRESUMO
Earlier spring phenology observed in many plant species in recent decades provides compelling evidence that species are already responding to the rising global temperatures associated with anthropogenic climate change. There is great variability among species, however, in their phenological sensitivity to temperature. Species that do not phenologically "track" climate change may be at a disadvantage if their growth becomes limited by missed interactions with mutualists, or a shorter growing season relative to earlier-active competitors. Here, we set out to test the hypothesis that phenological sensitivity could be used to predict species performance in a warming climate, by synthesizing results across terrestrial warming experiments. We assembled data for 57 species across 24 studies where flowering or vegetative phenology was matched with a measure of species performance. Performance metrics included biomass, percent cover, number of flowers, or individual growth. We found that species that advanced their phenology with warming also increased their performance, whereas those that did not advance tended to decline in performance with warming. This indicates that species that cannot phenologically "track" climate may be at increased risk with future climate change, and it suggests that phenological monitoring may provide an important tool for setting future conservation priorities.
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Mudança Climática , Ecossistema , Desenvolvimento Vegetal , Plantas/classificação , California , Demografia , Modelos Biológicos , Especificidade da EspécieRESUMO
Darwin's classic image of an "entangled bank" of interdependencies among species has long suggested that it is difficult to predict how the loss of one species affects the abundance of others. We show that for dynamical models of realistically structured ecological networks in which pair-wise consumer-resource interactions allometrically scale to the (3/4) power--as suggested by metabolic theory--the effect of losing one species on another can be predicted well by simple functions of variables easily observed in nature. By systematically removing individual species from 600 networks ranging from 10-30 species, we analyzed how the strength of 254,032 possible pair-wise species interactions depended on 90 stochastically varied species, link, and network attributes. We found that the interaction strength between a pair of species is predicted well by simple functions of the two species' biomasses and the body mass of the species removed. On average, prediction accuracy increases with network size, suggesting that greater web complexity simplifies predicting interaction strengths. Applied to field data, our model successfully predicts interactions dominated by trophic effects and illuminates the sign and magnitude of important nontrophic interactions.
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Ecologia , Cadeia Alimentar , Dinâmica Populacional , Animais , Biomassa , Tamanho Corporal , Extinção Biológica , Comportamento Alimentar , Modelos TeóricosRESUMO
We propose defining a field of research called 'archaeoecology' that examines the past ~60 000 years of interactions between humans and ecosystems to better understand the human place within them. Archaeoecology explicitly integrates questions, data, and approaches from archaeology and ecology, and coalesces recent and future studies that demonstrate the usefulness of integrating archaeological, environmental, and ecological data for understanding the past. Defining a subfield of archaeoecology, much as the related fields of environmental archaeology and palaeoecology have emerged as distinct areas of research, provides a clear intellectual context for helping us to understand the trajectory of human-ecosystem interactions in the past, during the present, and into the future.
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Arqueologia , Ecossistema , HumanosRESUMO
Restriction to analysis of births that survive past a specified gestational age (typically 20 weeks gestation) leads to biased exposure-outcome associations. This bias occurs when the cause of restriction (early pregnancy loss) is influenced by both the exposure and unmeasured factors that also affect the outcome. The aim of this study is to estimate the magnitude of bias resulting from left truncated data in the association between advanced maternal age and stillbirth. We simulated data for the causal pathway under a collider-stratification mechanism. Simulation parameters were based on an observed birth cohort from Western Australia and a range of plausible values for the prevalence of early pregnancy loss, unmeasured factor U and the odds ratios for the selection effects. Selection effects included the effects of maternal age on early pregnancy loss, U on early pregnancy loss, and U on stillbirth. We compared the simulation scenarios to the observed birth cohort that was truncated to pregnancies that survived beyond 20 gestational weeks. We found evidence of marginal downward bias, which was most prominent for women aged 40 + years. Overall, we conclude that the magnitude of bias due to left truncation is minimal in the association between advanced maternal age and stillbirth.
Assuntos
Aborto Espontâneo , Natimorto , Gravidez , Feminino , Humanos , Natimorto/epidemiologia , Idade Materna , Aborto Espontâneo/epidemiologia , Idade Gestacional , Viés , Fatores de RiscoRESUMO
OBJECTIVE: This study examined the association between family planning counselling receipt during the 12 months preceding the survey and postpartum modern contraceptive uptake in Ethiopia. We hypothesised that receiving family planning counselling either within the community setting by a field health worker or at a health facility by a healthcare attendant during the 12 months preceding the survey improves postpartum modern contraceptive uptake. DESIGN: We used a cross-sectional study of the Ethiopian Demographic and Health Survey conducted in 2016. SETTING: Ethiopia. PARTICIPANTS: A total of 1650 women who gave birth during the 12 months and had contact with service delivery points during the 12 months preceding the survey. PRIMARY OUTCOME: A weighted modified Poisson regression model was used to estimate an adjusted relative risk (RR) of postpartum modern contraceptives. RESULTS: Approximately half (48%) of the women have missed the opportunity to receive family planning counselling at the health service contact points during the 12 months preceding the survey. The postpartum modern contraceptive uptake was 27%. Two hundred forty-two (30%) and 204 (24%) of the counselled and not counselled women used postpartum modern contraceptive methods, respectively. Compared with women who did not receive counselling for family planning, women who received counselling had higher contraceptive uptake (RR 1.32, 95% CI 1.04 to 1.67). CONCLUSION: Significant numbers of women have missed the opportunity of receiving family planning counselling during contact with health service delivery points. Modern contraceptive uptake among postpartum women was low in Ethiopia. Despite this, our findings revealed that family planning counselling was associated with improved postpartum modern contraceptive uptake.
Assuntos
Anticoncepcionais , Serviços de Planejamento Familiar , Anticoncepção/métodos , Comportamento Contraceptivo , Aconselhamento , Estudos Transversais , Etiópia , Feminino , Humanos , Masculino , Período Pós-PartoRESUMO
(1) Background: Miscarriages occur in approximately 15-25% of all pregnancies. There is limited evidence suggesting an association between history of miscarriage and the development of diabetic and hypertensive disorders in women. This systematic review aims to collate the existing literature and provide up to date epidemiological evidence on the topic. (2) Methods: We will search CINAHL Plus, Ovid/EMBASE, Ovid/MEDLINE, ProQuest, PubMed, Scopus, Web of Science, and Google Scholar, using a combination of medical subject headings, keywords, and search terms, for relevant articles related to the association between miscarriage and the risk of diabetic and hypertensive disorders. Cross-sectional, case-control, nested case-control, case-cohort, and cohort studies published from inception to April 2022 will be included in the search strategy. Three reviewers will independently screen studies and the risk of bias will be assessed using the Joanna Briggs Institute Critical Appraisal tool. Where the data permit, a meta-analysis will be conducted. (3) Results: The results of this systematic review will be submitted to a peer-reviewed journal for publication. (4) Conclusions: The findings of this systematic review will instigate efforts to manage and prevent reproductive, cardiovascular, and metabolic health consequences associated with miscarriages.