Responses of a native and a recent invader snail to warming and dry conditions: the case of the lower Ebro River

Aquatic habitats have been highly modified by human actions that reduce their native diversity and create conditions suitable for tolerant alien species. Pomacea maculata was detected in 2009 in both the alluvial plain and the final stretch of the Ebro River. Since then, a permanent population has stabilized in the littoral area of the river where the water level fluctuates according to the river discharge. Melanopsis tricarinata is an endemic snail species highly affected by the reduction in its natural habitat. Currently, the two species do not share the same reaches in the river, but the possibility exists, as the distribution of the P. maculata is constantly increasing. This study aims to analyse the diets and to assess the responses of both snails to global change. The diet of both species was analysed in the field and their responses to water warming and dryness compared under laboratory conditions. This study includes the calculation of future river water temperatures based on air temperature projections. In addition, based on water discharge management scenarios, the study estimated the increase in dry river bed area. The diet of both snail species was similar and based on Cladophora. P. maculata better resisted high temperatures and dry conditions than M. tricarinata. The projections of water temperatures showed an increase in daily temperatures, especially in summer. The hydraulic model suggested that a relevant increase in dry river bed areas will occur. Overall, these results provide insight into the global change factors that could favour P. maculata spread in the river and the reduction in suitable habitat for M. tricarinata and will be useful for future decisions of water discharge management

Increasing impact of warm droughts on northern ecosystem productivity over recent decades

This is the author accepted manuscript. The final version is available from Nature Research via the DOI in this recordData availability: The data to reproduce and further interpret the main results presented are publicly available at figshare. The TRENDY v.6 datasets applied in this study have been preprocessed by M.O. and are available from the University of Exeter (https://doi.org/10.24378/exe.2883) and on request. The original TRENDY v.6 datasets can be requested from S. Sitch ([email protected]) and P. Friedlingstein ([email protected]). The FLUXCOM dataset is publicly available through the FLUXCOM data portal (https://www.bgc-jena.mpg.de/geodb/projects/FileDetails.php). The LUE datasets are provided by W.K.S. and publicly available at https://wkolby.org/data-code/. The CRUNCEP reanalysis data are available through the Climatic Research Unit data portal (https://crudata.uea.ac.uk/cru/data/ncep/#dataset_access).Code availability: All relevant codes to reproduce the figures presented in this study are publicly available at figshare (https://doi.org/10.6084/m9.figshare.14845005). Further codes and materials are available from D.G. on request.Climate extremes such as droughts and heatwaves have a large impact on terrestrial carbon uptake by reducing gross primary production (GPP). While the evidence for increasing frequency and intensity of climate extremes over the last decades is growing, potential systematic adverse shifts in GPP have not been assessed. Using observationally-constrained and process-based model data, we estimate that particularly northern midlatitude ecosystems experienced a +10.6% increase in negative GPP extremes in the period 2000–2016 compared to 1982–1998. We attribute this increase predominantly to a greater impact of warm droughts, in particular over northern temperate grasslands (+95.0% corresponding mean increase) and croplands (+84.0%), in and after the peak growing season. These results highlight the growing vulnerability of ecosystem productivity to warm droughts, implying increased adverse impacts of these climate extremes on terrestrial carbon sinks as well as a rising pressure on global food security.Swiss National Science Foundation (SNSF)Helmholtz Initiative and Networking FundNewton FundNAS

Bilinear modulation models for seasonal tables of counts

We propose generalized linear models for time or age-time tables of seasonal counts, with the goal of better understanding seasonal patterns in the data. The linear predictor contains a smooth component for the trend and the product of a smooth component (the modulation) and a periodic time series of arbitrary shape (the carrier wave). To model rates, a population offset is added. Two-dimensional trends and modulation are estimated using a tensor product B-spline basis of moderate dimension. Further smoothness is ensured using difference penalties on the rows and columns of the tensor product coefficients. The optimal penalty tuning parameters are chosen based on minimization of a quasi-information criterion. Computationally efficient estimation is achieved using array regression techniques, avoiding excessively large matrices. The model is applied to female death rate in the US due to cerebrovascular diseases and respiratory diseases

Structural insights into regulation of nuclear receptors by ligands

Nuclear receptors are DNA-binding transcription factors, the transcriptional function of many of which depends on the binding of ligands, a feature that distinguishes nuclear receptors from other transcription factors. This review will summarize recent advances in our knowledge of the interaction between selected nuclear receptors and their cognate ligands

Identification of COUP-TFII Orphan Nuclear Receptor as a Retinoic Acid–Activated Receptor

The chicken ovalbumin upstream promoter-transcription factors (COUP-TFI and II) make up the most conserved subfamily of nuclear receptors that play key roles in angiogenesis, neuronal development, organogenesis, cell fate determination, and metabolic homeostasis. Although the biological functions of COUP-TFs have been studied extensively, little is known of their structural features or aspects of ligand regulation. Here we report the ligand-free 1.48 Å crystal structure of the human COUP-TFII ligand-binding domain. The structure reveals an autorepressed conformation of the receptor, where helix α10 is bent into the ligand-binding pocket and the activation function-2 helix is folded into the cofactor binding site, thus preventing the recruitment of coactivators. In contrast, in multiple cell lines, COUP-TFII exhibits constitutive transcriptional activity, which can be further potentiated by nuclear receptor coactivators. Mutations designed to disrupt cofactor binding, dimerization, and ligand binding, substantially reduce the COUP-TFII transcriptional activity. Importantly, retinoid acids are able to promote COUP-TFII to recruit coactivators and activate a COUP-TF reporter construct. Although the concentration needed is higher than the physiological levels of retinoic acids, these findings demonstrate that COUP-TFII is a ligand-regulated nuclear receptor, in which ligands activate the receptor by releasing it from the autorepressed conformation

Low-Resolution Molecular Models Reveal the Oligomeric State of the PPAR and the Conformational Organization of Its Domains in Solution

The peroxisome proliferator-activated receptors (PPARs) regulate genes involved in lipid and carbohydrate metabolism, and are targets of drugs approved for human use. Whereas the crystallographic structure of the complex of full length PPARγ and RXRα is known, structural alterations induced by heterodimer formation and DNA contacts are not well understood. Herein, we report a small-angle X-ray scattering analysis of the oligomeric state of hPPARγ alone and in the presence of retinoid X receptor (RXR). The results reveal that, in contrast with other studied nuclear receptors, which predominantly form dimers in solution, hPPARγ remains in the monomeric form by itself but forms heterodimers with hRXRα. The low-resolution models of hPPARγ/RXRα complexes predict significant changes in opening angle between heterodimerization partners (LBD) and extended and asymmetric shape of the dimer (LBD-DBD) as compared with X-ray structure of the full-length receptor bound to DNA. These differences between our SAXS models and the high-resolution crystallographic structure might suggest that there are different conformations of functional heterodimer complex in solution. Accordingly, hydrogen/deuterium exchange experiments reveal that the heterodimer binding to DNA promotes more compact and less solvent-accessible conformation of the receptor complex

Revisiting mortality deceleration patterns in a gamma-Gompertz-Makeham framework

We calculate life-table aging rates (LARs) for overall mortality by estimating a gamma-Gompertz-Makeham (G GM) model and taking advantage of LAR’s parametric representation by Vaupel and Zhang [34]. For selected HMD countries, we study how the evolution of estimated LAR patterns could explain observed 1) longevity dynamics, and 2) mortality improvement or deterioration at different ages. Surprisingly, the age of mortality deceleration x showed almost no correlation with a number of longevity measures apart from e0. In addition, as mortality concentrates at older ages with time, its characteristic bell-shaped pattern becomes more pronounced. Moreover, in a GGM framework, we identify the impact of senescent mortality on shape of the rate of population aging. We also find evidence for a strong relationship between x and the statistically significant curvilinear changes in the evolution of e0 over time. Finally, model-based LARs appear to be consistent with point b) of the “heterogeneity hypothesis” [12]: mortality deceleration, due to selection effects, should shift to older ages as the level of total adult mortality declines

Quantifying Sources of Variability in Infancy Research Using the Infant-Directed-Speech Preference

Psychological scientists have become increasingly concerned with issues related to methodology and replicability, and infancy researchers in particular face specific challenges related to replicability: For example, high-powered studies are difficult to conduct, testing conditions vary across labs, and different labs have access to different infant populations. Addressing these concerns, we report on a large-scale, multisite study aimed at (a) assessing the overall replicability of a single theoretically important phenomenon and (b) examining methodological, cultural, and developmental moderators. We focus on infants’ preference for infant-directed speech (IDS) over adult-directed speech (ADS). Stimuli of mothers speaking to their infants and to an adult in North American English were created using seminaturalistic laboratory-based audio recordings. Infants’ relative preference for IDS and ADS was assessed across 67 laboratories in North America, Europe, Australia, and Asia using the three common methods for measuring infants’ discrimination (head-turn preference, central fixation, and eye tracking). The overall meta-analytic effect size (Cohen’s d) was 0.35, 95% confidence interval = [0.29, 0.42], which was reliably above zero but smaller than the meta-analytic mean computed from previous literature (0.67). The IDS preference was significantly stronger in older children, in those children for whom the stimuli matched their native language and dialect, and in data from labs using the head-turn preference procedure. Together, these findings replicate the IDS preference but suggest that its magnitude is modulated by development, native-language experience, and testing procedure

A multi-element psychosocial intervention for early psychosis (GET UP PIANO TRIAL) conducted in a catchment area of 10 million inhabitants: study protocol for a pragmatic cluster randomized controlled trial

Multi-element interventions for first-episode psychosis (FEP) are promising, but have mostly been conducted in non-epidemiologically representative samples, thereby raising the risk of underestimating the complexities involved in treating FEP in 'real-world' services