Individuals and not just species are key components of biodiversity, yet the relationship between intraspecific diversity and ecosystem functioning in microbial systems remains largely untested. This ...limits our ability to understand and predict the effects of altered genetic diversity in regulating key ecosystem processes and functions. Here, we use a model fungal system to test the hypothesis that intraspecific genotypic richness of Paxillus obscurosporus stimulates biomass and CO(2) efflux, but that this is dependent on nitrogen supply. Using controlled experimental microcosms, we show that populations containing several genotypes (maximum 8) of the fungus had greater productivity and produced significantly more CO(2) than those with fewer genotypes. Moreover, intraspecific diversity had a much stronger effect than a four-fold manipulation of the carbon:nitrogen ratio of the growth medium. The effects of intraspecific diversity were underpinned by strong roles of individuals, but overall intraspecific diversity increased the propensity of populations to over-yield, indicating that both complementarity and selection effects can operate within species. Our data demonstrate the importance of intraspecific diversity over a range of nitrogen concentrations, and the need to consider fine scale phylogenetic information of microbial communities in understanding their contribution to ecosystem processes.
Abstract
The dynamics of a stratified oceanic bottom boundary layer (BBL) over an insulating, sloping surface depend critically on the intersection of density surfaces with the bottom. For an imposed ...along-slope flow, the cross-slope Ekman transport advects density surfaces and generates a near-bottom geostrophic thermal wind shear that opposes the background flow. A limiting case occurs when a momentum balance is achieved between the Coriolis force and a restoring buoyancy force in response to the displacement of stratified fluid over the slope: this is known as Ekman arrest. However, the turbulent characteristics that accompany this adjustment have received less attention. We present two estimates to characterize the state of the BBL based on the mixed layer thickness:
H
a
and
H
L
. The former characterizes the steady Ekman arrested state, and the latter characterizes a relaminarized state. The derivation of
H
L
makes use of a newly defined slope Obukhov length
L
s
that characterizes the relative importance of shear production and cross-slope buoyancy advection. The value of
H
a
can be combined with the temporally evolving depth of the mixed layer
H
to form a nondimensional variable
H
/
H
a
that provides a similarity prediction of the BBL evolution across different turbulent regimes. The length scale
L
s
can also be used to obtain an expression for the wall stress when the BBL relaminarizes. We validate these relationships using output from a suite of three-dimensional large-eddy simulations. We conclude that the BBL reaches the relaminarized state before the steady Ekman arrested state. Calculating
H
/
H
a
and
H
/
H
L
from measurements will provide information on the stage of oceanic BBL development being observed. These diagnostics may also help to improve numerical parameterizations of stratified BBL dynamics over sloping topography.
Neighborhood socioeconomic deprivation is associated with adverse health outcomes. We sought to determine if neighborhood socioeconomic deprivation was associated with adherence to immunosuppressive ...medications after liver transplantation.
We conducted a secondary analysis of a multicenter, prospective cohort of children enrolled in the medication adherence in children who had a liver transplant study (enrollment 2010-2013). Participants (N = 271) received a liver transplant ≥1 year before enrollment and were subsequently treated with tacrolimus. The primary exposure, connected to geocoded participant home addresses, was a neighborhood socioeconomic deprivation index (range 0-1, higher indicates more deprivation). The primary outcome was the medication level variability index (MLVI), a surrogate measure of adherence to immunosuppression in pediatric liver transplant recipients. Higher MLVI indicates worse adherence behavior; values ≥2.5 are predictive of late allograft rejection.
There was a 5% increase in MLVI for each 0.1 increase in deprivation index (95% confidence interval, -1% to 11%; P = 0.08). Roughly 24% of participants from the most deprived quartile had an MLVI ≥2.5 compared with 12% in the remaining 3 quartiles (P = 0.018). Black children were more likely to have high MLVI even after adjusting for deprivation (adjusted odds ratio 4.0 95% confidence interval, 1.7-10.6).
This is the first study to evaluate associations between neighborhood socioeconomic deprivation and an objective surrogate measure of medication adherence in children posttransplant. These findings suggest that neighborhood context may be an important consideration when assessing adherence. Differential rates of medication adherence may partly explain links between neighborhood factors and adverse health outcomes following pediatric liver transplantation.
The catalytic activities of eukaryotic protein kinases (EPKs) are regulated by movement of the C-helix, movement of the N and C lobes upon ATP binding, and movement of the activation loop upon ...phosphorylation. Statistical analysis of the selective constraints associated with AGC kinase functional divergence reveals conserved interactions between these regulatory regions and three regions of the C-terminal tail (C-tail): the N-lobe tether (NLT), the active-site tether (AST), and the C-lobe tether (CLT). The NLT serves as a docking site for an upstream kinase PDK1 and, upon activation, positions the C-helix within the ATP binding pocket. The AST directly interacts with the ATP binding pocket, and the CLT interacts with the interlobe linker and the αC-β4 loop, which appears to serve as a hinge for C-helix movement. The C-tail is a hallmark of AGC functional divergence inasmuch as most of the conserved core residues that distinguish AGC kinases from other EPKs are associated with the NLT, AST, or CLT. Moreover, several AGC catalytic core conserved residues that interact with the C-tail strikingly diverge from the canonical residues observed at corresponding positions in nearly all other EPKs, suggesting that the catalytic core may have coevolved with the C-tail in AGC kinases. These observations, along with the fact that the C-tail is needed for catalytic activity suggests that the C-tail is a cis-acting regulatory module that can also serve as a regulatory "handle," to which trans-acting cellular components can bind to modulate activity.
Misconceptions of photoprotection in skin of color Taylor, Susan C.; Alexis, Andrew F.; Armstrong, April W. ...
Journal of the American Academy of Dermatology,
March 2022, 2022-03-00, 20220301, Letnik:
86, Številka:
3
Journal Article
Recenzirano
Terrestrial sunlight is the portion of electromagnetic radiation that is emitted by the sun and reaches Earth's surface. It encompasses 3 major components: UV radiation (290-400 nm), visible light ...(400-700 nm), and infrared radiation. The deleterious effects of UV radiation have been appreciated for decades, particularly among those with light skin tones (Fitzpatrick skin types I-II) who primarily manifest with burns of varying degrees of severity with sun exposure. In recent years, studies have increasingly shown the negative impact of visible light on skin health, particularly in individuals with skin of color (Fitzpatrick skin types IV-VI), including the exacerbation of hyperpigmentation disorders such as melasma and post-inflammatory hyperpigmentation, as well as induction of the former. Recommendations from medical societies and the US Food and Drug Administration for photoprotection have been evolving along with the knowledge base. Yet, misconceptions about skin damage related to sunlight and the benefits of photoprotection (particularly among those with Fitzpatrick skin types V-VI) are still prevalent among both clinicians and patients. Among patients with skin of color, disorders of hyperpigmentation and other consequences from sun exposure have been associated with impaired skin health and negative burden on quality of life. This review summarizes currently available evidence of the impact of both UV and visible wavelengths and the low utilization of photoprotection measures among people with skin of color, with the goal of providing recommendations to help educate patients.
A method for the coordination of multiple battery energy storage systems (BESSs) is proposed for voltage control in low-voltage distribution networks (LVDNs). The main objective of this method is to ...solve over-voltage problems with multiple suitably sized energy storage systems. The performance of coordinated control is compared with noncoordinated control using both a real-time digital simulator and a MATLAB model of a real U.K. LVDN with a high installed capacity of solar photovoltaics. This is used to show that coordinated control is robust and effective at preventing voltage rise problems in LVDNs. The proposed coordinated control scheme is able to use the BESSs more evenly, and therefore reduces the costs of battery replacement to the storage operator in terms of both number of batteries and maintenance visits.
We show that intracellular transcription of G-rich regions produces novel DNA structures, visible by electron microscopy as large (150-500 bp) loops. These G-loops are formed cotranscriptionally, and ...they contain G4 DNA on one strand and a stable RNA/DNA hybrid on the other. G-loop formation requires a G-rich nontemplate strand and reflects the unusual stability of the rG/dC base pair. G-loops and G4 DNA form efficiently within plasmid genomes transcribed in vitro or in Escherichia coli. These results establish that G4 DNA can form in vivo, a finding with implications for stability and maintenance of all G-rich genomic regions.
This book assesses how low-carbon generation, the advance of energy storage and consumer-based models can help decarbonise electricity supplies at a national level.
This book is built around ...developing a decarbonised electricity mix for Britain which reduces fossil fuels from 50% of supply in 2018 down to levels within 2030 interim carbon goals on the way to net zero emissions. Crossland explores the idea of a future energy storage mix which blends domestic batteries, vehicles, thermal stores and pumped hydro to provide a flexible, responsive electricity system. He then goes on to look at how much storage can contribute to decarbonisation in a multitude of contexts – from domestic to national electricity. This book also discusses how efficiency and self-sufficiency can bring about a decarbonised electricity use within our homes today. Britain is used as the main example, but the themes and conclusions are applicable to a global audience, and each chapter draws on practical case studies from around the world to illustrate key ideas.
Drawing on the author’s experience in delivering and analysing low-carbon energy projects in the UK, Sub-Saharan Africa, Latin America and Oceania, this book will be of great relevance to students, scholars and industry specialists with an interest in energy technology, policy and storage.
We examined the prevalence and repeat offenses of college men, including fraternity men and student athletes, taking advantage of someone sexually while under the influence of alcohol. Preexisting ...data from the Core Alcohol and Other Drug Survey included a sample of 12,624 college men at 49 community and 4-year colleges. Results provide further evidence that the problem of campus rape is largely one of serial perpetration. More than 87% of alcohol-involved sexual assault was committed by serial perpetrators. Fraternity men and student athletes were significantly more likely to commit alcohol-involved sexual assault than other men on campus.
Bloom's helicase (BLM) is thought to prevent crossing-over during DNA double-strand-break repair (DSBR) by disassembling double-Holliday junctions (dHJs) or by preventing their formation. We show ...that the Saccharomyces cerevisiae BLM ortholog, Sgs1, prevents aberrant crossing-over during meiosis by suppressing formation of joint molecules (JMs) comprising three and four interconnected duplexes. Sgs1 and procrossover factors, Msh5 and Mlh3, are antagonistic since Sgs1 prevents dHJ formation in msh5 cells and sgs1 mutation alleviates crossover defects of both msh5 and mlh3 mutants. We propose that differential activity of Sgs1 and procrossover factors at the two DSB ends effects productive formation of dHJs and crossovers and prevents multichromatid JMs and counterproductive crossing-over. Strand invasion of different templates by both DSB ends may be a common feature of DSBR that increases repair efficiency but also the likelihood of associated crossing-over. Thus, by disrupting aberrant JMs, BLM-related helicases maximize repair efficiency while minimizing the risk of deleterious crossing-over.
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