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Bile acids and the gut microbiome: an emerging therapeutic
No full textAge-related diseases, including Type 2 diabetes mellitus and metabolic syndrome are a pressing
global health challenge that is expected to rise. They are associated with the composition of the gut
microbiome, which has roles in metabolism, inflammation, and the immune system. Recent research
has unveiled that bile acids, in addition to their well-established roles in maintaining metabolic
homeostasis, can significantly impact the composition and function of the gut microbiome and hold
potential as therapeutic agents that can promote the growth of beneficial gut bacteria, thereby
conferring health benefits.
Using batch culture in vitro fermentation models, several bile acids were screened for their effects on
beneficial bacterial species and corresponding short chain fatty acids (SCFAs). From the bile acids
screened, 7-KLCA, UDCA and UCA were found to increase the numbers of probiotic bacterial groups,
with subsequent three-stage continuous culture fermentations demonstrating the differing effects of
these bile acids on the gut microbiota. 7-KLCA was found to promote the growth of important
butyrate-producing bacterial species, including Faecalibacterium prausnitzii, Eubacterium rectale,
and Roseburia species. Bile acid profiling results elucidated to the rapid metabolism of 7-KLCA to
UDCA by bacterial species with cell culture studies suggesting that bile acid treatment can lead to
expression changes in genes associated with a healthier metabolic phenotype.
Taken collectively, these findings suggest that 7-KLCA may exert therapeutic effects with the
potential to modulate gut microbiota, promote the production of health-promoting SCFAs and
regulate gene expression. They highlight its promise as a novel agent in the prevention, as a
nutraceutical supplement, and even as a possible therapeutic agent, in the treatment of metabolic
diseases, including prediabetes and T2DM
Net surface energy flux over the globe and Asian monsoon region in CMIP6 high-resolution models
No full textThe net surface energy flux (Fs) is critical to the Earth’s energy budget and surface processes, but there are still simulation uncertainties at global and regional scales. This study investigates simulated Fs biases and sources over the Asian monsoon region (AMR) in CMIP6 HighResMIP atmospheric models. The global state is investigated first to check if there is any systematic model bias which can affect the AMR as well. In the AMR, the Fs is predominantly upward during winter and downward during summer owing to the seasonal variation in SWs and THF. 95% of the winter Fs bias over the AMR comes from THF, primarily because of the latent heat flux bias. SWs and THF contribute 40–90% and 70–90%, respectively, to the summer Fs bias. The systematic biases of SWs and LWs can be attributed to biases in circulation patterns and cloud cover, whereas biases in THF are influenced primarily by near-surface processes. The high-resolution models perform well in terms of Fs, THF, and the circulation (wind speed at 850 hPa and 10 m) in the low-level troposphere, particularly in winter. The winter multimodel mean error is reduced by 21.5–63.6% in Fs and 25.5–76.7% in THF across the three AMR subregions. Seven out of the nine high-resolution models have higher skill scores for winter Fs and THF than their low-resolution counterparts do in South Asia (SA), with corresponding model numbers of 8 (Fs) and 7 (THF) in East Asia (EA) and the western North Pacific (WNP). This study reveals the advantages of increased horizonal resolution in Fs simulations
Making sense of uncertainties: ask the right question
Get PDFEarth observation data should inform decision making, but good decisions can only be made if the uncertainties in the data are taken into account. Making sense of uncertainty information can be difficult, however, because uncertainties represent the statistical spread in the observations (e.g., expressed as x +/- y), which does not relate directly to one specific use case of the data. Here, we propose a Bayesian framework to transform Earth observation product uncertainties into actionable information, i.e., estimates of how confident one can be in the occurrence of specific events of interest given the data and their uncertainty. We demonstrate this framework using two case examples: (i) monitoring drought severity based on soil moisture; and (ii) estimating coral bleaching risk based on sea surface temperature. In both cases, we show that ignoring uncertainties can easily lead to misinterpretation of the data, making any decisions based on these data unlikely to be the best course of action. The proposed framework is general and can, in principle, be applied to a wide range of applications. Doing so requires a careful dialogue between data users, to formulate meaningful use cases and decision criteria, and data producers, to provide a rigorous description of their data and its uncertainties. The next step would then be to confront the uncertainty-informed estimates of event probabilities (created by the framework proposed here) with the costs and benefits of possible courses of action in order to make the best possible decisions that maximise socioeconomic merit
Generalized Hilbert matrix operators acting on Bergman spaces
Get PDFIn this article, we study the generalized Hilbert matrix
operator Γμ acting on the Bergman spaces Ap of the unit disc
for 1 ≤ p < ∞. In particular, we characterize the measures
μ for which the operator Γμ is bounded, determine the exact
value of the norm for p ≥ 4, and provide norm estimates for
the other values of p. Additionally, we observe an unexpected
behavior in the case p = 2. Finally, we characterize the
measures μ for which Γμ is compact by calculating its exact
essential norm
The effects of the correlated colour temperature of light on thermal sensation in the built environment: a systematic review and meta-analysis
Get PDFRecently, the effect of the correlated colour temperature (CCT) of light on human thermal sensation has drawn much attention from the built environment area because of its potential application to change indoor comfortable temperature set points and save energy in buildings. Many studies have been conducted on this topic, and the results have proved inconsistent, making them difficult to use in actual practice. To further understand the validity and application range of the effect, it is urgent to research and reflect on a heterogenous selection of relevant studies. Thus, this paper aims to conduct a systematic review of existing studies, investigate the reasons for heterogeneity and explore the effect of moderators on experimental results. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) method was used for the systematic review, while the method of Meta-analysis was utilised to investigate the reasons for heterogeneity and the effect of moderators. The meta-analysis found that a higher CCT can lead to a cooler thermal sensation, while environmental factors, such as the background thermal environment, temperature and exposure duration, moderate the effect's magnitude. The results of the meta-analysis suggest that in the thermally neutral environment, the effect of CCT on thermal sensation is most significant. Meanwhile, the magnitude of the effect diminishes with the duration of exposure. For the first time, this study explains the reasons for the heterogeneity of existing studies and reveals the influence of moderators on the thermal effect of CCT
Evaluating the use of perennial flower margins for sustainable aphid pest control services
Get PDFApple is a globally important crop that is suscepMble to many pests and diseases. PromoMng natural
pest control could increase crop yield and quality and reduce reliance on harmful pesMcides. The
addiMon of nectar and pollen rich floral habitat is a commonly used management pracMce in
agricultural ecosystems. This pracMce has been demonstrated to increase the abundance of predators
and parasites of orchard pests(natural enemies), although there is less evidence of the extent to which
this could improve pest control services, yield or profit. This thesis aimed to evaluate the ecological
and economic effects of perennial flower margins in UK apple orchards for control of an economically
significant global crop pest, Dysaphis plantaginea, rosy apple aphid.
Empirical data collected over two years from different locaMons in commercial orchards, either with or
without flower margins, revealed that flower margins provided a disMnct plant community, and their
presence increased natural enemy diversity in orchard ground vegetaMon compared to orchards
without flower margins. However, there was no evidence of broad differences between natural enemy
taxa abundance, diversity, or community structure on the apple trees. Despite this, there was reduced
spread of D. plantaginea on aphid infested trees in orchards with flower margins, and subsequently a
reduced number of trees with fruit damage, from 80% to 48%, with effects seen up to 50 m from the
flower margin during a year with higher aphid infestaMon levels. The reducMon in the spread of D.
plantaginea, and percentage of trees with apple damage, varied between the two years and at
different distances from the orchard edge. An economic model of these benefits when compared to
the costs associated with flower margins, revealed that flower strips bordering the crop area could be
a promising economic investment for D. plantaginea control if they do not replace apple trees. If non-crop land were not available and apple trees were being replaced by the flowers, establishment of a
flower strip in the centre of an orchard instead of the edge, could recoup opportunity costs. The
economic model showed that installing a flower strip in the centre of the orchard for 5 years could
return £2997 per hectare per year if aphid infestaMon levels were high. However, the results suggest
that this is context-dependent, and a similar flower strip could cost £210 if placed on crop land as a
margin instead of in the orchard centre.
This work is the first to demonstrate a reducMon in fruit damage by D. plantaginea at harvest in
orchards with a flower margin compared to a control orchards with mown primarily grass margins, and
one of few to evaluate the economic effect. The results highlight the potenMal for established perennial
flower margins to deliver orchard-scale, sustainable, economically viable D. plantaginea control
benefits, and provides insights into the spill-over distance of the effects. Flower margins could be used
as a tool to support more sustainable producMon in apple orchards. The factors that influence the
extent of these potenMal benefits are discussed
Training human super-recognisers’ detection and discrimination of AI-generated faces
No full textGenerative Adversarial Networks (GANs) can create realistic synthetic faces, which have the potential to be used for nefarious purposes. The synthetic faces produced by GANs are difficult to detect and are often judged to be more realistic than real faces. Training programmes have been developed to improve human synthetic face detection accuracy, with mixed results. Here we investigate synthetic face detection and discrimination in super-recognisers (who have exceptional face recognition skills), and typical-ability control participants. We also devised a training
procedure which sought to highlight rendering artifacts. In two different experimental designs, we found that super-recognisers (total N = 283) were better at detecting and discriminating synthetic faces than controls (total N = 381), where control participants were below chance without training. Trained super-recognisers and controls had significantly better performance than those without
training, and the magnitude of the training effect was similar in both groups. Our results suggest that super-recognisers are using cues unrelated to rendering artifacts to detect and discriminate synthetic faces, and that an easily implementable training procedure increases their performance to above chance levels. These results have implications for real-world scenarios, where trained
super-recognisers' performance could be harnessed for synthetic face detection
Perceptual decision-making in autistic and non-autistic adults and relationship with autism- and ADHD-related traits
Get PDFAutistic individuals respond to sensory information in perceptual tasks differently than non-autistic individuals. However, it is unclear which component processes are altered, and how other aspects of neurodiversity (e.g., ADHD traits) affect these processing stages. Here, we applied diffusion models to decompose numerosity task performance into distinct processing stages, across two pre-registered studies with rigorous blinded analyses. In Study 1, we validated our approach and investigated relationships between diffusion-model parameters and autism- and ADHD-related traits in the general population ( n = 130). Study 2 investigated group differences between diagnosed autistic ( n = 100) and non-autistic ( n = 100) adults with comparable non-verbal reasoning ability, and assessed relationships with ADHD traits. Study 1 found no relationships between diffusion-model parameters and autism and ADHD-related traits in the general population. Study 2 revealed that autistic individuals had shorter non-decision times than non-autistic individuals, reflecting less time taken for sensory encoding and/or response generation, with no group differences in sensory evidence accumulation or response caution. We also found that individuals with higher motor hyperactivity-impulsivity had lower non-decision times and that individuals with higher verbal hyperactivity-impulsivity accumulated evidence more slowly. The diffusion model, therefore, reveals the convergence and divergence of processing stages in autism and across ADHD-related traits
Crafting solitude: an intentional approach to solitude in emerging adults’ everyday life
Get PDFSolitude is often stigmatized, yet research suggests intentional time
alone can be beneficial. This research tests “Solitude Crafting,” a novel
two-part intervention to reshape emerging adults’ experiences by destigmatizing solitude and guiding meaningful solitary activities. Pilot
study (N = 120) assessed the intervention’s feasibility and impact over
five days. The full study (N = 75) tested the intervention, examining
Solitude Crafting alongside a comparison time point in a staggered,
within-subject design. Results indicated post-intervention improvements
in emotional well-being, with participants attributing these benefits to
the intervention. Our findings present Solitude Crafting as a promising
avenue for reframing attitudes toward solitude and enhancing well-being
when alone
Extratropical cyclones act as a ‘bridge’ to the concurrent impact of ENSO on the Arctic oscillation during boreal winter
Get PDFThis study demonstrates that the concurrent influence of ENSO caused by the poleward translation of extra-tropical cyclones (ECs) over the North Atlantic is more significant than the 1-year lagged impact of ENSO through poleward propagating atmospheric angular momentum. Specific results show that during El Niño (La Niña) winter, the anomalous atmospheric horizontal heat advection from the Pacific to the Atlantic, which is caused by the southward (northward) displacement of the westerly jet stream, enhances (weakens) the atmospheric baroclinicity over the subtropical North Atlantic. Subsequently, the modified baroclinicity drives intensified (reduced) baroclinic energy conversion from the eddy available potential energy to the eddy kinetic energy, which shifts the genesis locations of ECs southward (northward) and suppresses (enhances) their poleward translation into the Arctic. Ultimately, through the combined thermodynamic and dynamical forcing inherent to ECs activity, the negative (positive) AO pattern is generated in the concurrent El Niño (La Niña) winter