Despite extensive research, the pathophysiology and prevention of pre-eclampsia remain elusive, diagnosis is challenging, and pre-eclampsia remains associated with adverse maternal and perinatal outcomes. Angiogenic biomarkers, including placental growth factor (PlGF) and soluble fms-like tyrosine kinase 1 (sFlt-1), have been identified as valuable biomarkers for preterm pre-eclampsia, accelerating diagnosis and reducing maternal adverse outcomes by risk stratification, with enhanced surveillance for high-risk women. PlGF-based testing is increasingly being implemented into clinical practice in several countries. This review provides healthcare providers with an understanding of the evidence for PlGF-based testing and describes the practicalities and challenges to implementation.
Over thirty species of littoral marine Gammaridea occur along the coasts of the North Atlantic. From one to several species can coexist in a single region. There is an evident, inverse relationship between egg incubation time and temperature (from 14 to > 120 days) and consequent trends in the size of the animals on reaching maturity (from 5 mm in warmer waters to 30 mm in the coldest ones) and in lifespan (from < 6 months to > 5 years). Littoral gammarids are a good example of the shrinking size effect of increasing temperatures and size-related species diversity. In large species the annual cohorts of the population (3 to 5 annual size groups) functionally replace the adults of smaller species. The ongoing warming of the European Arctic seas may extend the distribution limits of boreal species so that more Gammarus species may appear on northern coasts hitherto occupied by just one or at most two species.
Objective: High data quality is essential to ensure the validity of clinical and research inferences based on it. However, these data quality assessments are often missing even though these data are used in daily practice and research. Our objective was to evaluate the data quality of our high-resolution electronic database (HRDB) implemented in our pediatric intensive care unit (PICU). Design: A prospective validation study of a HRDB. Setting: A 32-bed pediatric medical, surgical and cardiac PICU in a tertiary care freestanding maternal-child health center in Canada. Population: All patients admitted to the PICU with at least one vital sign monitored using a cardiorespiratory monitor connected to the central monitoring station. Interventions: None Measurements and Main Results: Between June 2017 and August 2018, data from 295 patient days were recorded from medical devices and 4,645 data points were video recorded and compared to the corresponding data collected in the HRDB. Statistical analysis showed an excellent overall correlation (R2=1), accuracy (100%), agreement (bias=0, limits of agreement=0), completeness (2% missing data) and reliability (ICC=1) between recorded and collected data within clinically significant pre-defined limits of agreement. Divergent points could all be explained. Conclusions: This prospective validation of a representative sample showed an excellent overall data quality.
The Arctic is warming at an unprecedented rate. One relatively under researched process is how seasonally frozen soils and changes thereof affect the water cycle. As frozen soils thaw, flow pathways within a watershed open, allowing for enhanced hydrologic connectivity between groundwater and rivers. As the connectivity of flow paths increase, the storage-discharge relationship of a watershed changes. The objective of this study is to quantify trends and spatio-temporal differences in the degree of linearity in the storage-discharge relationships for sixteen watersheds within Northern Sweden throughout the years of 1950 and 2018. We demonstrate a clear increase in non-linearity of the storage-discharge relationship over time for all catchments with twelve out of sixteen watersheds (75%) having a statistically significant increase in non-linearity. Springs have significantly more linear storage-discharge relationships than summer for twelve watersheds (75%), which supports the idea that seasonally frozen soil with a low degree of hydrological connectivity have a linear storage-discharge relationship. For the period considered, spring showed the greater change in storage-discharge relationship trends than summer, signifying changes in recessions are occurring during the thawing period. Separate storage-discharge analyses combined with preceding winter conditions demonstrated that especially cold winters with little snow yield springs and summers with more linear storage-discharge relationships. We show that streamflow recession analysis shows ongoing hydrological change of an arctic landscape as well as offers new metrics for tracking the change across arctic and sub-arctic landscapes.
Objective: To evaluate the effectiveness of virtual reality as a distraction technique in the management of acute pain and anxiety during outpatient hysteroscopy. Methods: A parallel group, prospective randomised controlled trial was conducted at a UK University Hospital (August to October 2018) (ClinicalTrials.gov Id: NCT03699280). Forty consenting, eligible women were randomised to virtual reality intervention (immersive video content as a distraction method) or standard care during outpatient hysteroscopy. Pain and anxiety outcomes were measured as a numeric rating score (scale of 0-10). Results: Compared to standard care, women with virtual reality intervention experienced less average pain (score 6.0 vs 3.7, mean difference 2.3, 95% CI 0.61-3.99, p=0.009) and anxiety (score 5.45 vs 3.3, mean difference 2.15, 95% CI 0.38-3.92, p=0.02). Conclusion: Virtual Reality was effective in reducing pain and anxiety during outpatient hysteroscopy in a pilot trial. Its wide potential role in ambulatory gynaecologic procedures needs further evaluation.
The Southern Ocean is one of the most isolated marine ecosystems, characterized by high levels of endemism, diversity, and biomass. Ascidians are among the dominant groups in Antarctic benthic assemblages, thus recording the evolutionary patterns of this group is crucial to improve our current understanding of the assembly of this polar ocean. We studied the genetic variation within Cnemidocarpa verrucosa sensu lato, one of the most widely distributed abundant and studied ascidian species in Antarctica. Using a mitochondrial and a nuclear gene (COI and 18S), the phylogeography of fifteen populations distributed along the Antarctic Peninsula and South America (Burdwood Bank/MPA Namuncurá) was characterized, where the bimodal distribution of the genetic distance suggested the existence of two species within the nominal C. verrucosa. When re-evaluating morphological traits to distinguish between genetically defined species, the presence of a basal disc in one of the genotypes could be a morphological trait to differentiate the species. These results are surprising due to the large research that has been carried out with the conspicuous C. verrucosa with no differentiation between species. Furthermore, it provides important tools to distinguish species in the field and laboratory. But also, these results give new insights to patterns of differentiation between closely related species that are distributed in sympatry, where the permeability of species boundaries still needs to be well understood.
Soil clay content is one of the primary intrinsic soil properties affecting soil erodibility, but few studies have tested the effects of clay amendment on soil wind erosion. The objective of this study was therefore to evaluate the effect of progressive clay amendment on soil wind erosion in the inland Pacific Northwest (iPNW), where there is a high soil erodibility risk due to the arid and semi-arid environment. Clay amendment significantly increased crust crushing energy when physical soil crusts formed after simulated rainfall. Crusts were then subject to simulated tillage to create an erodible soil surface before determining wind erosion in a wind tunnel. Soil loss significantly decreased with increasing clay amendment, even for low clay amendments (2%). In addition, the rate of change in erosion decreased with increasing amounts of clay amendment. Clay amendment was more effective in decreasing soil loss for two sandy loams or soil types with lower clay content. Clay amendment decreased soil loss primarily due to its impact on increasing aggregate geometric mean diameter (GMD), but aggregate crushing energy is also important in decreasing soil loss in terms of decreasing abrasion flux. Clay amendment is thus an effective way to restrain land deterioration in terms of increasing crust crushing energy, aggregate GMD, and decreasing abrasion flux.
It is possible to estimate the prior probability of pathogenicity for germline disease gene variants based on bioinformatic prediction of variant effect/s. However, routinely used approaches have likely led to the underestimation and underreporting of variants located outside donor and acceptor splice site motifs that affect mRNA processing. This review presents information about hereditary cancer gene germline variants, outside native splice sites, with experimentally validated splicing effects. We list 81 exonic variants that impact splicing regulatory elements in BRCA1, BRCA2, MLH1, MSH2, MSH6 and PMS2. We utilized a pre-existing large-scale BRCA1 functional dataset to map functional splicing regulatory elements, assess the relative performance of different tools to predict effects of 283 variants on such elements, and develop a generic workflow to prioritize variants that may impact splicing regulatory elements. We also describe rare examples of intronic variants that impact branchpoint sites and create pseudoexons. We discuss the challenges in predicting variant effect on branchpoint site usage and pseudoexonization, and suggest strategies to improve the bioinformatic prioritization of such variants for experimental validation. Importantly, our review highlights the importance of considering impact of variants outside donor and acceptor motifs on mRNA splicing and disease causation.
Population dynamics models combine density-dependence and environmental effects. Ignoring sampling uncertainty might lead to biased estimation of the strength of density-dependence. This is typically addressed using state-space model approaches, which integrate sampling error and population process estimates. Such models seldom include an explicit link between the sampling procedures and the true abundance, which is common in capture-recapture settings. However, many of the models proposed to estimate abundance in the presence of heterogeneity lead to incomplete likelihood functions and cannot be straightforwardly included in state-space models. We assessed the importance of estimating sampling error explicitly by taking an intermediate approach between ignoring uncertainty in abundance estimates and fully specified state-space models for density-dependence estimation based on autoregressive processes. First, we estimated individual capture probabilities based on a heterogeneity model, using a conditional multinomial likelihood, followed by a Horvitz-Thompson estimate for abundance. Second, we estimated coefficients of autoregressive models for the log abundance. Inference was performed using the methodology of integrated nested Laplace approximation (INLA). We performed an extensive simulation study to compare our approach with estimates disregarding capture history information, and using R-package VGAM, for different parameter specifications. The methods were then applied to a real dataset of gray-sided voles Myodes rufocanus from Northern Norway. We found that density-dependence estimation was improved when explicitly modelling sampling error in scenarios with low innovation variances, in which differences in coverage reached up to 8% in estimating the coefficients of the autoregressive processes. In this case, the bias also increased assuming a Poisson distribution in the observational model. For high innovation variances, the differences between methods were small and it appeared less important to model heterogeneity.
1. The reduction of plant diversity following eutrophication threatens many ecosystems worldwide. Yet, the mechanisms by which species are lost following nutrient enrichment are still not completely understood, nor are the details of when such mechanisms act during the growing season, which hampers understanding and the development of mitigation strategies. 2. Using a common garden competition experiment, we found that early-season differences in growth rates among five perennial grass species measured in monoculture predicted short-term competitive dominance in pairwise combinations and that this effect was stronger under a fertilisation treatment. 3. We also examined the role of early-season growth rate in determining the outcome of competition along an experimental nutrient gradient in an alpine meadow. Early differences in growth rate between species predicted short-term competitive dominance under both ambient and fertilized conditions and competitive exclusion under fertilized conditions. 4. The results of these two studies suggests that plant species growing faster during the early stage of the growing season gain a competitive advantage over species that initially grow more slowly, and that this advantage is magnified under fertilisation. This finding is consistent with the theory of asymmetric competition for light in which fast-growing species can intercept incident light and hence outcompete and exclude slower-growing (and hence shorter) species. We predict that the current chronic nutrient inputs into many terrestrial ecosystems worldwide will reduce plant diversity and maintain low biodiversity state by continuously favouring fast-growing species. Biodiversity management strategies should focus on controlling nutrient inputs and reducing the growth of fast-growing species early in the season.
Continuity in research group collective knowledge is critical for running a successful research program but in an undergraduate research lab, this can be particularly challenging. A wiki site dedicated to the research laboratory, a lab wiki, can bridge gaps in student-to-student knowledge transfer and contribute to longevity of a research program. A lab wiki is an organized, easily accessible, collaborative resource that can contain tutorials, group-specific directions, links to resources and guides to writing papers or proposals. The wiki language is easy for students to pick up and contributes to their participation in preserving group knowledge. This tutorial introduces the concept of a lab wiki, the advantages of it, example content and practical implementation advice.
Objective: To determine whether planned cesarean section (CS) for a second delivery protects anal continence in women with obstetrical anal sphincter lesions. Design: Randomized trial. Setting: 6 maternity units in the Paris area. Sample : Women at high risk of sphincter lesions (first delivery with 3d degree laceration and/or forceps) but no symptomatic anal incontinence. Methods : Endoanal ultrasound was performed in the third trimester of the second pregnancy. Women with sphincter lesions were randomized to planned CS or vaginal delivery (VD). Main outcome measures : Anal continence at 6 months post-partum. Secondary outcomes were urinary continence, sexual morbidity, maternal and neonatal morbidities and worsening of external sphincter lesions. Results : Anal sphincter lesions were detected by ultrasound in 264/434 women enrolled (60.8%) ; 112 were randomized to planned VD and 110 to planned CS. At 6-8 weeks after delivery, there was no significant difference in anal continence between the 2 groups. At 6 months after delivery, median Vaizey scores of anal continence were 1 [IQR 0-4] in the CS group and 1 [IQR 0-3] in the VD group (p = 0.34). There were no significant differences for urinary continence, sexual functions or for other maternal and neonatal morbidities. Conclusions : In women with asymptomatic obstetrical anal sphincter lesions diagnosed by ultrasound, planning a CS had no significant impact on anal continence 6 months after the second delivery. These results do not support advising systematic CS for this indication.
Extreme droughts of increased frequency due to climate change poses great challenges to the sustainability of plantations in drylands worldwide. Millions of plantations on China’s Loess Plateau which are mainly in drylands are threatened by serious degradation due to water scarcity. Here we aim to disentangle the impacts of combinations of terracing and mulching on water use strategy and its response to extreme droughts in a rainfed jujube (Ziziphus jujuba) plantation on the semiarid Loess Plateau, using three-year in situ field observations. Pruned jujube branches and maize straw were mulched on half-moon terraces to form two combined treatments, referred to as JBT and MST, respectively. The efficacy of these two combinations on the water use strategy of jujube trees was compared with terracing alone (SHT) and control (no terrace). We found that extreme drought clearly reduced soil water storage (SWS) under all treatments. However, the combined treatments showed significantly (P<0.05) higher SWS than the SHT and control. Furthermore, the combined treatments enhanced soil water use in deep layers during both normal and drought years, thus helping jujube trees to resist droughts. Moreover, the extreme drought significantly reduced transpiration whereas the moderate drought increased transpiration at both seasonal and annual scales. Nonetheless, the combined treatments were associated with enhanced transpiration compared to the SHT and control during drought periods. Finally, jujube trees exhibited isohydric behavior which also helped them to cope with prolonged droughts. Overall, the findings here may provide insights into land management of dryland plantations worldwide under climate change.
We investigate mixed type boundary-transmission problems of the generalized thermo-electro-magneto elasticity (GTEME) theory for complex elastic anisotropic layered structures containing interfacial cracks. This type of problems are described mathematically by systems of partial differential equations with appropriate transmission and boundary conditions for six dimensional unknown physical field (three components of the displacement vector, electric potential function, magnetic potential function, and temperature distribution function). We apply the potential method and the theory of pseudodifferential equations and prove uniqueness and existence theorems of solutions to different type mixed boundary-transmission problems in appropriate Sobolev spaces. We analyze smoothness properties of solutions near the edges of interfacial cracks and near the curves where different type boundary conditions collide.
We use adaptive dynamics models to study how changes in the abiotic environment affect patterns of evolutionary dynamics and diversity in evolving communities of organisms with complex phenotypes. The models are based on the logistic competition model and environmental changes are implemented as a temporal change of the carrying capacity as a function of phenotype. In general we observe that environmental changes cause a reduction in the number of species, in total population size, and in phenotypic diversity. The rate of environmental change is crucial for determining whether a community survives or undergoes extinction. Until some critical rate of environmental changes, species are able to follow evolutionarily the shifting phenotypic optimum of the carrying capacity, and many communities adapt to the changing conditions and converge to new stationary states. When environmental changes stop, such communities gradually restore their initial phenotypic diversity.
Satellite-based solar-induced chlorophyll fluorescence (SIF) has the potential for an early detection and accurate impact assessment of meteorological drought on vegetation photosynthesis. However, how the response of satellite SIF to meteorological drought varies under different climatic conditions and biome types remains poorly understood. In this study, we determined the drought time-scale at which the vegetation photosynthesis response was highest based on the standardized precipitation evapotranspiration index (SPEI) and satellite SIF, and examined how the sensitivity of SIF signals from different ecosystems to drought varied along an aridity gradient in northern China. The results showed that spatial variability of the annual maximum SIF was constrained by wetness conditions and biome types. Annual maximum SIF was positively correlated with SPEI in 57.9% of vegetated lands (P < 0.05). 34.8% of humid ecosystems were characterized by a significant SIF-SPEI correlation (P < 0.05). This percentage reached 44%, 71.4% and 86.2% for arid, sub-humid and semi-arid ecosystems, respectively. The variation of SIF-SPEI correlations was a Gaussian function of the aridity index (AI), with the highest SIF-SPEI correlation appearing in the AI bin of 0.4 (0.37-0.46). The drivers for this pattern were vegetation composition and water availability. The variation of SIF time-scales in response to SPEI was a linear function of the AI, but the slope varied among biomes. To summarize with increasing aridity drought-induced declines in vegetation photosynthesis will be quicker and more significant.