Mitigating climate change and sustainably feeding our growing population in the changing climate are 2 significant challenges facing the global community. Engineering photosynthesis, nature's carbon ...capture machinery, can help us surmount these threats.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Augmented glycolysis due to metabolic reprogramming in lung myofibroblasts is critical to their profibrotic phenotype. The primary glycolysis byproduct, lactate, is also secreted into the ...extracellular milieu, together with which myofibroblasts and macrophages form a spatially restricted site usually described as fibrotic niche. Therefore, we hypothesized that myofibroblast glycolysis might have a non-cell autonomous effect through lactate regulating the pathogenic phenotype of alveolar macrophages. Here, we demonstrated that there was a markedly increased lactate in the conditioned media of TGF-β1 (transforming growth factor-β1)-induced lung myofibroblasts and in the BAL fluids (BALFs) from mice with TGF-β1- or bleomycin-induced lung fibrosis. Importantly, the media and BALFs promoted profibrotic mediator expression in macrophages. Mechanistically, lactate induced histone lactylation in the promoters of the profibrotic genes in macrophages, consistent with the upregulation of this epigenetic modification in these cells in the fibrotic lungs. The lactate inductions of the histone lactylation and profibrotic gene expression were mediated by p300, as evidenced by their diminished concentrations in p300-knockdown macrophages. Collectively, our study establishes that in addition to protein, lipid, and nucleic acid molecules, a metabolite can also mediate intercellular regulations in the setting of lung fibrosis. Our findings shed new light on the mechanism underlying the key contribution of myofibroblast glycolysis to the pathogenesis of lung fibrosis.
Most lost fishing gear is made of non-biodegradable plastics that may sink to the sea floor or drift around in currents. It may remain unnoticed until it shows up on coral reefs, beaches and in other ...coastal habitats. Stony corals have fragile skeletons and soft tissues that can easily become damaged when they get in contact with lost fishing gear. During a dive survey around Koh Tao, a small island in the Gulf of Thailand, the impact of lost fishing gear (nets, ropes, cages, lines) was studied on corals representing six different growth forms: branching, encrusting, foliaceous, free-living, laminar, and massive. Most gear (>95%) contained plastic. Besides absence of damage (ND), three categories of coral damage were assessed: fresh tissue loss (FTL), tissue loss with algal growth (TLAG), and fragmentation (FR). The position of the corals in relation to the fishing gear was recorded as either growing underneath (Un) or on top (On), whereas corals adjacent to the gear (Ad) were used as controls. Nets formed the dominant type of lost gear, followed by ropes, lines and cages, respectively. Branching corals were most commonly found in contact with the gear and also around it. Tubastraea micranthus was the most commonly encountered coral species, either Un, On, or Ad. Corals underneath gear showed most damage, which predominantly consisted of tissue loss. Fragmentation was less common than expected, which may be related to the low fragility of T. micranthus as dominant branching species. Even if nets serve as substrate for corals, it is recommended to remove them from reefs, where they form a major component of the plastic pollution and cause damage to corals and other reef organisms.
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•Abandoned fishing gear is a major component of litter on coral reefs around Koh Tao.•The derelict gear is composed of nets, ropes and lines made of non-biodegradable plastics.•The lost fishing gear is causing tissue loss and fragmentation in reef corals.•Abandoned fishing gear is able to serve as an artificial substrate for corals.•Tubastraea micranthus and fungiids are the most common corals colonizing lost gear.
Little is known about the environmental conditions that drive the spatiotemporal patterns of SARS-CoV-2. Preliminary research suggests an association with meteorological parameters. However, the ...relationship with temperature and humidity is not yet apparent for COVID-19 cases in US cities first impacted. The objective of this study is to evaluate the association between COVID-19 cases and meteorological parameters in select US cities. A case-crossover design with a distributed lag nonlinear model was used to evaluate the contribution of ambient temperature and specific humidity on COVID-19 cases in select US cities. The case-crossover examines each COVID case as its own control at different time periods (before and after transmission occurred). We modeled the effect of temperature and humidity on COVID-19 transmission using a lag period of 7 days. A subset of 8 cities were evaluated for the relationship with meteorological parameters and 5 cities were evaluated in detail. Short-term exposure to humidity was positively associated with COVID-19 transmission in 4 cities. The associations were small with 3 out of 4 cities exhibiting higher COVID19 transmission with specific humidity that ranged from 6 to 9 g/kg. Our results suggest that weather should be considered in infectious disease modeling efforts. Future work is needed over a longer time period and across different locations to clearly establish the weather-COVID19 relationship.
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•We studied daily temperature and humidity in COVID-19 morbidity.•We used a case-crossover and distributed lag nonlinear model.•We observed non-linear associations with humidity and temperature.•Humidity was the best predictor of COVID-19 transmission.•Results varied across select US cities despite accounting for social distancing measures.
The relationship between corals and dinoflagellates of the genus Symbiodinium is fundamental to the functioning of coral ecosystems. It has been suggested that reef corals may adapt to climate change ...by changing their dominant symbiont type to a more thermally tolerant one, although the capacity for such a shift is potentially hindered by the compatibility of different host-symbiont pairings. Here we combined transcriptomic and metabolomic analyses to characterize the molecular, cellular, and physiological processes that underlie this compatibility, with a particular focus on Symbiodinium trenchii, an opportunistic, thermally tolerant symbiont that flourishes in coral tissues after bleaching events. Symbiont-free individuals of the sea anemone Exaiptasia pallida (commonly referred to as Aiptasia), an established model system for the study of the cnidarian-dinoflagellate symbiosis, were colonized with the “normal” (homologous) symbiont Symbiodinium minutum and the heterologous S. trenchii. Analysis of the host gene and metabolite expression profiles revealed that heterologous symbionts induced an expression pattern intermediate between the typical symbiotic state and the aposymbiotic state. Furthermore, integrated pathway analysis revealed that increased catabolism of fixed carbon stores, metabolic signaling, and immune processes occurred in response to the heterologous symbiont type. Our data suggest that both nutritional provisioning and the immune response induced by the foreign “invader” are important factors in determining the capacity of corals to adapt to climate change through the establishment of novel symbioses.
Rapid rotation is a fundamental characteristic of classical Be stars and a crucial property allowing for the formation of their circumstellar disks. Past evolution in a mass and angular momentum ...transferring binary system offers a plausible solution to how Be stars attained their fast rotation. Although the subdwarf remnants of mass donors in such systems should exist in abundance, only a few have been confirmed due to tight observational constraints. An indirect method of detecting otherwise hidden companions is offered by their effect on the outer parts of Be star disks, which are expected to be disrupted or truncated. In the context of the infrared and radio continuum excess radiation originating in the disk, the disk truncation can be revealed by a turndown in the spectral energy distribution due to reduced radio flux levels. In this work, we search for signs of spectral turndown in a sample of 57 classical Be stars with radio data, which include new data for 23 stars and the longest-wavelength detections so far (λ 10 cm) for two stars. We confidently detect the turndown for all 26 stars with sufficient data coverage (20 of which are not known to have close binary companions). For the remaining 31 stars, the data are inconclusive as to whether the turndown is present or not. The analysis suggests that many if not all Be stars have close companions influencing their outer disks. If confirmed to be subdwarf companions, the mass transfer spin-up scenario might explain the existence of the vast majority of classical Be stars.
Abstract
We report the detection of 15 GHz radio continuum emission associated with the classical Cepheid variable star
δ
Cephei (
δ
Cep) based on observations with the Karl G. Jansky Very Large ...Array. Our results constitute the first probable detection of radio continuum emission from a classical Cepheid. We observed the star at pulsation phase
ϕ
≈ 0.43 (corresponding to the phase of maximum radius and minimum temperature) during three pulsation cycles in late 2018 and detected statistically significant emission (>5
σ
) during one of the three epochs. The observed radio emission appears to be variable at a ≳10% level on timescales of days to weeks. We also present an upper limit on the 10 GHz flux density at pulsation phase
ϕ
= 0.31 from an observation in 2014. We discuss possible mechanisms that may produce the observed 15 GHz emission, but cannot make a conclusive identification from the present data. The emission does not appear to be consistent with originating from a close-in, late-type dwarf companion, although this scenario cannot yet be strictly excluded. Previous X-ray observations have shown that
δ
Cep undergoes periodic increases in X-ray flux during pulsation phase
ϕ
≈ 0.43. The lack of radio detection in two out of three observing epochs at
ϕ
≈ 0.43 suggests that either the radio emission is not linked with a particular pulsation phase, or else that the strength of the generated radio emission in each pulsation cycle is variable.
Summary
The intimate relationship between scleractinian corals and their associated microorganisms is fundamental to healthy coral reef ecosystems. Coral‐associated microbes (Symbiodiniaceae and ...other protists, bacteria, archaea, fungi and viruses) support coral health and resilience through metabolite transfer, inter‐partner signalling, and genetic exchange. However, much of our understanding of the coral holobiont relationship has come from studies that have investigated either coral‐Symbiodiniaceae or coral‐bacteria interactions in isolation, while relatively little research has focused on other ecological and metabolic interactions potentially occurring within the coral multi‐partner symbiotic network. Recent evidences of intimate coupling between phytoplankton and bacteria have demonstrated that obligate resource exchange between partners fundamentally drives their ecological success. Here, we posit that similar associations with bacterial consortia regulate Symbiodiniaceae productivity and are in turn central to the health of corals. Indeed, we propose that this bacteria‐Symbiodiniaceae‐coral relationship underpins the coral holobiont's nutrition, stress tolerance and potentially influences the future survival of coral reef ecosystems under changing environmental conditions. Resolving Symbiodiniaceae‐bacteria associations is therefore a logical next step towards understanding the complex multi‐partner interactions occurring in the coral holobiont.
The template update problem Matthews, L.; Ishikawa, T.; Baker, S.
IEEE transactions on pattern analysis and machine intelligence,
2004-June, 2004-Jun, 2004-06-00, 20040601, Letnik:
26, Številka:
6
Journal Article
Recenzirano
Odprti dostop
Template tracking dates back to the 1981 Lucas-Kanade algorithm. One question that has received very little attention, however, is how to update the template so that it remains a good model of the ...tracked object. We propose a template update algorithm that avoids the "drifting" inherent in the naive algorithm.
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