bluuebunny/crossref_metadata_2025_split huggingface dataset:
PNU‐120596, a positive allosteric modulator of mammalian α7 nicotinic acetylcholine receptor, is a negative modulator of ligand‐gated chloride‐selective channels of the gastropod Lymnaea stagnalis
Authors: Vulfius Catherine A. , Lebedev Dmitrii S. , Kryukova Elena V. , Kudryavtsev Denis S. , Kolbaev Sergey N. , Utkin Yuri N. , Tsetlin Victor I. 
Published: April 2020

AbstractExcitatory α7 neuronal nicotinic receptors (nAChR) are widely expressed in the central and peripheral nervous and immune systems and are important for learning, memory, and immune response regulation. Specific α7 nAChR ligands, including positive allosteric modulators are promising to treat cognitive disorders, inflammatory processes, and pain. One of them, PNU‐120596, highly increased the neuron response to α7 agonists and retarded desensitization, showing selectivity for α7 as compared to heteromeric nAChRs, but was not examined at the inhibitory ligand‐gated channels. We studied PNU‐120596 action on anion‐conducting channels using voltage‐clamp techniques: it slightly potentiated the response of human glycine receptors expressed in PC12 cells, of rat GABAA receptors in cerebellar Purkinje cells and mouse GABAARs heterologously expressed in Xenopus oocytes. On the contrary, PNU‐120596 exerted an inhibitory effect on the receptors mediating anion currents in Lymnaea stagnalis neurons: two nAChR subtypes, GABA and glutamate receptors. Acceleration of the current decay, contrary to slowing down desensitization in mammalian α7 nAChR, was observed in L. stagnalis neurons predominantly expressing one of the two nAChR subtypes. Thus, PNU‐120596 effect on these anion‐selective nAChRs was just opposite to the action on the mammalian cation‐selective α7 nAChRs. A comparison of PNU‐120596 molecule docked to the models of transmembrane domains of the human α7 AChR and two subunits of L. stagnalis nAChR demonstrated some differences in contacts with the amino acid residues important for PNU‐120596 action on the α7 nAChR. Thus, our results show that PNU‐120596 action depends on a particular subtype of these Cys‐loop receptors.
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Responding to Digital Transformation by External Corporate Venturing: An Enterprising Family Identity and Communication Patterns Perspective
Authors: Prügl Reinhard , Spitzley Dinah Isabel 
Published: April 2020

AbstractDigital transformation increasingly requires activities located outside firm boundaries, for example via alliances with start‐up companies. Despite this, German Mittelstand firms, primarily owned and managed by enterprising families and seen as role models of innovation, appear reluctant to place strategic emphasis on venturing outside the firm’s boundaries when it comes to digital transformation. Drawing on the concepts of identity and communication patterns, we theorize on the mechanisms behind this behaviour. Applying structural equation modelling to a sample of 254 members of the next generation in enterprising families from Germany, we find that family communication patterns impact the strategic priority for or against external corporate venturing via identity‐related considerations.
Endogenous formation of multiple social groups
Authors: Nguyen Ngoc M. , Richefort Lionel , Vallée Thomas 
Published: April 2020

AbstractThis paper explores a model of group membership formation in which agents decide to join or not multiple social groups. The membership formation process induces a bipartite graph structure with social groups listed on one side and agents listed on the other side. Among members of multiple social groups, we consider two decisive types of agents: the grand star and the mini star. The former type is the unique agent in a society who participates in all social groups. The latter type includes agents who participate in more than one, but not all, social groups such that every social group pair has one and only one common member. We analyze the efficiency and stability conditions of group membership formation, and we establish sufficient conditions under which a connected graph that contains either a grand star or a set of mini stars becomes the unique strongly efficient and stable graph.
Melanopic illuminance defines the magnitude of human circadian light responses under a wide range of conditions
Authors: Brown Timothy M. 
Published: April 2020

AbstractOcular light drives a range of nonvisual responses in humans including suppression of melatonin secretion and circadian phase resetting. These responses are driven by intrinsically photosensitive retinal ganglion cells (ipRGCs) which combine intrinsic, melanopsin‐based, phototransduction with extrinsic rod/cone‐mediated signals. As a result of this arrangement, it has remained unclear how best to quantify light to predict its nonvisual effects. To address this, we analysed data from nineteen different laboratory studies that measured melatonin suppression, circadian phase resetting and/or alerting responses in humans to a wide array of stimulus types, intensities and durations with or without pupil dilation. Using newly established SI‐compliant metrics to quantify ipRGC‐influenced responses to light, we show that melanopic illuminance consistently provides the best available predictor for responses of the human circadian system. In almost all cases, melanopic illuminance is able to fully account for differences in sensitivity to stimuli of varying spectral composition, acting to drive responses that track variations in illumination characteristic of those encountered over civil twilight (~1‐1000 lux melanopic equivalent daylight illuminance). Collectively, our data demonstrate widespread utility of melanopic illuminance as a metric for predicting the circadian impact of environmental illumination. These data therefore provide strong support for the use of melanopic illuminance as the basis for guidelines that seek to regulate light exposure to benefit human health and to inform future lighting design.
The scale dependency of trait‐based tree neighborhood models
Authors: Zambrano Jenny , Beckman Noelle G. , Marchand Philippe , Thompson Jill , Uriarte María , Zimmerman Jess K. , Umaña María N. , Swenson Nathan G. 
Published: April 2020

AbstractQuestionsWe asked: (a) whether the strength of conspecific and heterospecific neighborhood crowding effects on focal tree survival and growth vary with neighborhood radii; and (b) if the relative strength of the effect of neighborhood interactions on tree growth and survival varies with neighborhood scale.LocationLuquillo Forest Dynamics Plot, Puerto Rico.MethodsWe used tree survival and growth data and included information on species‐mean trait values related to several leaf traits, maximum height, seed mass and wood density. We incorporated a tree neighborhood modeling approach that uses an area around a focal tree with a specified radius, to describe the interactions between a focal tree and its neighbors. We constructed survival and growth models for each functional trait using a Bayesian approach, and varied the size of the radius from 5 m to 30 m, at 5‐m intervals.ResultsThe results suggested that the estimated effects of conspecific and heterospecific neighbors on tree performance do not vary based on the size of the neighborhood (5–30 m), suggesting that the effects of conspecific and heterospecific neighbors on the performance of a focal tree likely do not vary substantially beyond a neighborhood radius of 5 m in the Luquillo forest. In contrast, the estimated strength of the functional neighborhood (effect of neighbors based on their functional trait values) on tree performance was dependent on the neighborhood range. Our results also suggested that the effects of trait distances and trait hierarchies on tree survival and growth are acting simultaneously and at the same spatial scales.ConclusionFindings from this study highlight the importance of spatial scale in community assembly processes, and specifically, call for increased attention when selecting the radius that defines the neighborhood around a focal tree as the selected neighborhood radius influences the community patterns discovered, and affects the conclusions about the drivers that control community assembly.
Coronavirus disease 2019 and prevalence of chronic liver disease: A meta‐analysis
Authors: Mantovani Alessandro , Beatrice Giorgia , Dalbeni Andrea 
Published: April 2020

AbstractAt present, there is scarce information regarding the global prevalence of chronic liver disease in individuals with coronavirus disease 2019 (COVID‐19) disease, which is becoming a global pandemic. The aim of this study was to assess the overall prevalence of chronic liver disease among patients with COVID‐19 disease by meta‐analysing data in observational studies and to investigate the relationship between liver damage and COVID‐19 disease. We included 11 observational studies for a total of 2034 adult individuals (median age 49 years [IQR 45‐54], 57.2% men). The overall prevalence of chronic liver disease at baseline was 3% (95% CI 2%‐4%; I2 = 29.1%). Individuals with severe COVID‐19 disease had relevant alterations of liver enzymes and coagulative profile, probably due to the innate immune response against the virus. Further studies are needed to better investigate the causes of liver injury in patients with COVID‐19 disease and the effect of treatment for COVID‐19 on the liver.
Foraging speed and precision of arbuscular mycorrhizal fungi under field conditions: An experimental approach
Authors: Šmilauer Petr , Šmilauerová Marie , Kotilínek Milan , Košnar Jiří 
Published: April 2020

AbstractTo better understand the ecology of arbuscular mycorrhizal (AM) symbiosis, we need to measure functional traits of individual fungal virtual taxa under field conditions. The efficiency of AM fungi in locating nutrient‐rich patches in soil space is one of their central traits in this symbiotic relationship. We used plots of a long‐term field experiment in grassland with manipulated functional group composition of host plant community to establish ingrowth patches with substrate free of roots and fungi and with varying nutrient availability. Comparison of the original AM fungal community before patch creation with that present 9 weeks after patch establishment enabled us to estimate relative hyphal foraging speed for 41 fungal taxa, and a comparison of the fungal community in neighbouring patches differing in nutrient availability provided estimates of hyphal foraging precision for 22 taxa. Members of two dominant fungal families, Glomeraceae and Claroideoglomeraceae, differed in their foraging speed and precision. Glomeraceae taxa responded more slowly, but with a higher focus on enriched patches. We further demonstrated the usefulness of the obtained fungal functional traits by testing the differences between grass and dicotyledonous plant hosts using a data set obtained in another experiment at the same plots. Grass species hosted AM fungal communities with higher foraging speed, but lower foraging precision than the dicotyledonous species. Our study results support the use of field experiments for measuring comparative characteristics of AM fungi, which are highly elusive (or misrepresented) under controlled conditions.
An “omics” approach to bridge community ecology and island biogeography
Authors: Matos‐Maraví Pável 
Published: April 2020

AbstractUnderstanding the dynamics of communities in space and time requires reconciling ecological and evolutionary processes, including colonization, adaptation, speciation and extinction. In practice, this has been challenging because empirical data obtained by traditional methods and predictive models typically focus on particular processes driving local community assembly and biogeographical structure. In this issue of Molecular Ecology, by using phylogenomics, population genomics and phenomics approaches, Darwell et al. show that ant community assembly on islands is governed by predictable eco‐evolutionary trends of geographical range expansion, adaptive radiation and local population decline. The authors provide one of the most robust lines of evidence that the evolutionary progression of island communities may often be directional and repeatable, as predicted by the concept of taxon cycles.
High genomic diversity in the bank vole at the northern apex of a range expansion: The role of multiple colonizations and end‐glacial refugia
Authors: Marková Silvia , Horníková Michaela , Lanier Hayley C. , Henttonen Heikki , Searle Jeremy B. , Weider Lawrence J. , Kotlík Petr 
Published: April 2020

AbstractThe history of repeated northern glacial cycling and southern climatic stability has long dominated explanations for how genetic diversity is distributed within temperate species in Eurasia and North America. However, growing evidence indicates the importance of cryptic refugia for northern colonization dynamics. An important geographic region to assess this is Fennoscandia, where recolonization at the end of the last glaciation was restricted to specific routes and temporal windows. We used genomic data to analyse genetic diversity and colonization history of the bank vole (Myodes glareolus) throughout Europe (>800 samples) with Fennoscandia as the northern apex. We inferred that bank voles colonized Fennoscandia multiple times by two different routes; with three separate colonizations via a southern land‐bridge route deriving from a “Carpathian” glacial refugium and one via a north‐eastern route from an “Eastern” glacial refugium near the Ural Mountains. Clustering of genome‐wide SNPs revealed high diversity in Fennoscandia, with eight genomic clusters: three of Carpathian origin and five Eastern. Time estimates revealed that the first of the Carpathian colonizations occurred before the Younger Dryas (YD), meaning that the first colonists survived the YD in Fennoscandia. Results also indicated that introgression between bank and northern red‐backed voles (Myodes rutilus) took place in Fennoscandia just after end‐glacial colonization. Therefore, multiple colonizations from the same and different cryptic refugia, temporal and spatial separations and interspecific introgression have shaped bank vole genetic variability in Fennoscandia. Together, these processes drive high genetic diversity at the apex of the northern expansion in this emerging model species.
Adult‐onset frequent non‐convulsive status epilepticus in a patient with ring chromosome 20 syndrome
Authors: Liu Xia , Omote Yoshio , Ikegami Ken , Tadokoro Koh , Takemoto Mami , Hishikawa Nozomi , Yamashita Toru , Ohta Yasuyuki , Abe Koji 
Published: April 2020

AbstractWe report a 31‐year‐old woman with ring chromosome 20 syndrome who presented with epilepsy staring from 16 years old and loss of consciousness from 30 years old. Her neurological examinations and psychological testing were normal, without dysmorphic features. No abnormalities were found in neuroimaging. Electroencephalogram recording showed typical non‐convulsive status epilepticus associated with alteration of consciousness. Her diagnosis was based on the cytogenetic analysis indicating that her karyotype was 46, XX, r(20)(p13q13.3)[9]/46, XX[21]. She had refractory epilepsy and improved by a combination of valproate and lacosamide.
A theoretical and empirical assessment of stomatal optimization modeling
Authors: Wang Yujie , Sperry John S. , Anderegg William R. L. , Venturas Martin D. , Trugman Anna T. 
Published: April 2020

SummaryOptimal stomatal control models have shown great potential in predicting stomatal behavior and improving carbon cycle modeling. Basic stomatal optimality theory posits that stomatal regulation maximizes the carbon gain relative to a penalty of stomatal opening. All models take a similar approach to calculate instantaneous carbon gain from stomatal opening (the gain function). Where the models diverge is in how they calculate the corresponding penalty (the penalty function). In this review, we compare and evaluate 10 different optimization models in how they quantify the penalty and how well they predict stomatal responses to the environment. We evaluate models in two ways. First, we compare their penalty functions against seven criteria that ensure a unique and qualitatively realistic solution. Second, we quantitatively test model against multiple leaf gas‐exchange datasets. The optimization models with better predictive skills have penalty functions that meet our seven criteria and use fitting parameters that are both few in number and physiology based. The most skilled models are those with a penalty function based on stress‐induced hydraulic failure. We conclude by proposing a new model that has a hydraulics‐based penalty function that meets all seven criteria and demonstrates a highly predictive skill against our test datasets.
Rhizosphere allocation by canopy‐forming species dominates soil CO2 efflux in a subarctic landscape
Authors: Parker Thomas C. , Clemmensen Karina E. , Friggens Nina L. , Hartley Iain P. , Johnson David , Lindahl Björn D. , Olofsson Johan , Siewert Matthias B. , Street Lorna E. , Subke Jens‐Arne , Wookey Philip A. 
Published: April 2020

Summary

In arctic ecosystems, climate change has increased plant productivity. As arctic carbon (C) stocks predominantly are located belowground, the effects of greater plant productivity on soil C storage will significantly determine the net sink/source potential of these ecosystems, but vegetation controls on soil CO2 efflux remain poorly resolved.

In order to identify the role of canopy‐forming species in belowground C dynamics, we conducted a girdling experiment with plots distributed across 1 km2 of treeline birch (Betula pubescens) forest and willow (Salix lapponum) patches in northern Sweden and quantified the contribution of canopy vegetation to soil CO2 fluxes and belowground productivity.

Girdling birches reduced total soil CO2 efflux in the peak growing season by 53%, which is double the expected amount, given that trees contribute only half of the total leaf area in the forest. Root and mycorrhizal mycelial production also decreased substantially. At peak season, willow shrubs contributed 38% to soil CO2 efflux in their patches.

Our findings indicate that C, recently fixed by trees and tall shrubs, makes a substantial contribution to soil respiration. It is critically important that these processes are taken into consideration in the context of a greening arctic because productivity and ecosystem C sequestration are not synonymous.
Polyploid plants obtain greater fitness benefits from a nutrient acquisition mutualism
Authors: Forrester Nicole J. , Rebolleda‐Gómez Maria , Sachs Joel L. , Ashman Tia‐Lynn 
Published: April 2020

SummaryPolyploidy is a key driver of ecological and evolutionary processes in plants, yet little is known about its effects on biotic interactions. This gap in knowledge is especially profound for nutrient acquisition mutualisms, despite the fact that they regulate global nutrient cycles and structure ecosystems. Generalism in mutualistic interactions depends on the range of potential partners (niche breadth), the benefits obtained and ability to maintain benefits across a variety of partners (fitness plasticity). Here, we determine how each of these is influenced by polyploidy in the legume–rhizobium mutualism.We inoculated a broad geographic sample of natural diploid and autotetraploid alfalfa (Medicago sativa) lineages with a diverse panel ofSinorhizobiumbacterial symbionts. To analyze the extent and mechanism of generalism, we measured host growth benefits and functional traits.Autotetraploid plants obtained greater fitness enhancement from mutualistic interactions and were better able to maintain this across diverse rhizobial partners (i.e. low plasticity in fitness) relative to diploids. These benefits were not attributed to increases in niche breadth, but instead reflect increased rewards from investment in the mutualism.Polyploid plants displayed greater generalization in bacterial mutualisms relative to diploids, illustrating another axis of advantage for polyploids over diploids.
Changes in canine inclination after rapid and slow maxillary expansion compared to untreated controls
Authors: Caprioglio Alberto , Castiglioni Francesco , Sambataro Sergio , Giuntini Veronica , Comaglio Ilaria , Lorvetti Federica , Fastuca Rosamaria 
Published: April 2020

AbstractObjectsPalatally displaced canines (PDC) might represent condition causing several clinical problems, such as roots resorption and malocclusion, and can develop palatal canine impaction. Some interceptive treatments such as rapid maxillary expansion were suggested in order to foster maxillary canine eruption. Among expansion protocols, no data are available about differences between rapid and slow maxillary expansion on maxillary canine eruption. The aim of this study was therefore to evaluate α‐angle changes in palatally displaced canines using rapid and slow maxillary expansion compared to untreated control patients.Setting and sample populationThe final sample comprised 19 patients treated with rapid maxillary expansion (RME group), 17 treated with slow maxillary expansion (SME group) and 22 control patients (Control group).Materials and methodsα‐angle was measured on panoramic films to detect canine inclination at the beginning, and at the end of maxillary expansion treatment or observation, time and changes over time were compared.ResultsIn the comparisons among groups, RME group was the only group showing a decrease in α‐angle measurements that was statistically significant also when compared to the other groups, except for the left side when compared to SME group.ConclusionRME treatment significantly and positively affected canine position when compared to SME treatment and control group.
Three‐dimensional analyses of short‐ and long‐term effects of rapid maxillary expansion on nasal cavity and upper airway: A systematic review and meta‐analysis
Authors: Niu Xiaowen , Di Carlo Gabriele , Cornelis Marie A. , Cattaneo Paolo M. 
Published: April 2020

AbstractIntroductionThe purpose of this systematic review was to evaluate the three‐dimensional (3D) changes occurring at short‐ and long‐term follow‐up after rapid maxillary expansion (RME) in nasal cavity (NC) and upper airway (UA) in growing patients.MethodsA literature search up to 1 July 2019 was performed. Randomized and non‐randomized clinical trials and cohort studies comparing the effects of RME in a paediatric population using 3D analyses based on computed tomography (CT), cone‐beam CT and MRI were included. The risks of bias of the included studies were assessed using the Cochrane Collaboration's risk of bias tool, the GRADE approach and a customized tool. The random‐effects meta‐analyses of the mean differences and 95% confidence intervals of NC and UA volume changes were carried out, followed by subgroup analyses.ResultsTwenty‐seven studies were included, with 18 selected for quantitative synthesis. Immediately after expansion, the nasopharynx and oropharynx increased significantly. After 3 months of retention, only the NC and nasopharynx showed a significant volume increase. Two studies mentioned the use of a sleep‐disordered breathing questionnaire, and one study reported the difference before and after RME. None of the 27 articles included assessed the correlation between the skeletal widening and NC or UA volume changes after RME.ConclusionsThe existing evidence confirmed only the short‐term positive effect of RME on expanding the volume of the NC and the upper part of the UA. However, long‐term stability could not be sustained.