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Overfishing of top predators along the western Atlantic coastline has led to a trophic cascade in salt marshes, with increases in herbivorous purple marsh crab (Sesarma reticulatum (Say, 1817)) abundances in North American estuaries leading to overgrazing of cordgrass (Spartina alterniflora Loisel.) and shoreline erosion. To evaluate potential physiological limits on the range of S. reticulatum within an estuary, we evaluated survival and physiological tolerance of S. reticulatum from the Ashepoo-Combhee-Edisto (ACE) River Basin in South Carolina, USA, to combinations of salinity (5[per thousand] and 30[per thousand]) and pH (pH 6.6,7.6, and 8.6) challenges, representative of estuarine extremes. Survival, haemolymph ion concentrations, and gill [Na.sup.+],[K.sup.+]-ATPase (NKA) and vacuolar-type [H.sup.+]-ATPase (VHA) activity were measured after a 48 h exposure to each experimental condition. Survival was nearly 100% and osmoregulatory control was maintained across estuarine salinity and pH ranges. Sesarma reticulatum appeared to be robust to all potential combinations of salinity and pH stressors examined in this study, and therefore are likely unrestricted in their fundamental niche based on these stressors throughout an estuary. Key words: purple marsh crab, Sesarma reticulatum, osmoregulation, salinity, pH, estuary. La surpêche de superprédateurs le long de la côte ouest de l'Atlantique a mené à une cascade trophique dans les marais salés dans laquelle des augmentations de l'abondance du crabe violet des marécages (Sesarma reticulatum (Say, 1817)) herbivore dans les estuaires nord-américains ont entraîné une surconsommation de spartine (Spartina alterniflora Loisel.) et l'érosion des rives. Afin d'évaluer les limites physiologiques potentielles de l'aire de répartition de S. reticulatum dans un estuaire, nous avons évalué la survie et la tolérance physiologique de S. reticulatum du bassin versant des rivières Ashepoo-Combhee-Edisto (ACE) en Caroline du Sud (États-Unis) en réponse à différentes combinaisons de salinité (5 [per thousand] et 30 [per thousand]) et de pH (6,6, 7,6 et 8,6) représentatives d'extrêmes estuariens. Le taux de survie, les concentrations hémolymphatiques d'ions et l'activité de la N[a.sup.+], [K.sup.+]-ATPase (NKA) et de la [H.sup.+]-ATPase de type vacuolaire (VHA) dans les branchies ont été mesurés après une exposition de 48 h à chacune des conditions expérimentales. La survie était de près de 100 % et l'osmorégulation était maintenue dans toute la fourchette de salinités et de pH estuariens. Les S. reticulatum ont semblé résister à toutes les combinaisons possibles de facteurs de stress associés à la salinité et au pH examinés dans l'étude; par conséquent, ces facteurs de stress ne limiteraient vraisemblablement pas la niche fondamentale de l'espèce dans un estuaire. [Traduit par la Rédaction] Mots-clés : crabe violet des marécages, Sesarma reticulatum, osmorégulation, salinité, pH, estuaire., Introduction Salt marsh habitat loss along the western Atlantic coast has become an increasing problem in the last 40 years (Bertness et al. 2014). The pronounced vegetation die-off is believed [...]

A catalog of transcription factor (TF) binding sites in the genome is critical for deciphering regulatory relationships. Here, we present the culmination of the efforts of the modENCODE (model organism Encyclopedia of DNA Elements) and modERN (model organism Encyclopedia of Regulatory Networks) consortia to systematically assay TF binding events in vivo in two major model organisms, Drosophila melanogaster (fly) and Caenorhabditis elegans (worm). These data sets comprise 605 TFs identifying 3.6 M sites in the fly and 356 TFs identifying 0.9 M sites in the worm, and represent the majority of the regulatory space in each genome. We demonstrate that TFs associate with chromatin in clusters termed "metapeaks," that larger metapeaks have characteristics of high-occupancy target (HOT) regions, and that the importance of consensus sequence motifs bound by TFs depends on metapeak size and complexity. Combining ChIP-seq data with single-cell RNA-seq data in a machine-learning model identifies TFs with a prominent role in promoting target gene expression in specific cell types, even differentiating between parent-daughter cells during embryogenesis. These data are a rich resource for the community that should fuel and guide future investigations into TF function. To facilitate data accessibility and utility, all strains expressing green fluorescent protein (GFP)-tagged TFs are available at the stock centers for each organism. The chromatin immunoprecipitation sequencing data are available through the ENCODE Data Coordinating Center, GEO, and through a direct interface that provides rapid access to processed data sets and summary analyses, as well as widgets to probe the cell-type-specific TF-target relationships., (© 2024 Kudron et al.; Published by Cold Spring Harbor Laboratory Press.)

Parenting style influences a child's overall diet quality and establishes food preferences. Parenting style and "food rules" for children differ by eating at home or away from home. Eating meals away from home is increasing despite associations with consumption of unhealthy foods and higher weight status. The objective of the current study was to compare parenting practices and decision-making at restaurants versus at home. A mixed methods approach was utilized: facilitated, individual interviews to explore decision-making and parenting practices; written questionnaires for socio-demographic information; and body mass index. Summaries and emergent themes were generated based on examination of tapes and transcripts. Descriptive statistics were computed for questionnaire data. Twenty-five mothers of children of five to eight years who ate at restaurants at least two times per week participated. Mothers reported more permissive food rules at restaurants yet maintained higher behavioral expectations. Mothers were also more likely to make decisions about whether they eat out, where to eat, and children's meal selections than their children. The findings suggest that parenting practices toward overall behavior and food choices may differ at restaurants than at home, highlighting the importance of healthy menu options, further research, and educational strategies., (Copyright © 2017 Elsevier Ltd. All rights reserved.)