159370 research outputs found
Sort by
Phanerozoic icehouse climates as the result of multiple solid-Earth cooling mechanisms
Get PDFThe Phanerozoic climate has been interrupted by two long “icehouse” intervals, including the current icehouse of the last ~34 million years. While these cool intervals correspond to lower atmospheric CO2, it is unclear why CO2 levels fell, with hypotheses suggesting changes in CO2 degassing rates or modification of silicate weathering through changing continental lithology or paleogeography. Here, we construct an Earth System Model that integrates these proposed cooling mechanisms in detail. The model can reproduce the broad geologic record of ice cap expansion, allowing us to infer the primary drivers of long-term climate change. Our results indicate that recent icehouse climates required a combination of different cooling mechanisms acting simultaneously and were not driven by a single known process, potentially explaining why icehouses have been rarer than greenhouses over Earth history
Antiferroelectric Order in Nematic Liquids: Flexoelectricity Versus Electrostatics
Get PDFThe recent discovery of ferroelectric nematic liquid crystalline phases marks a major breakthrough in soft matter research. An intermediate phase, often observed between the nonpolar and the ferroelectric nematic phase, shows a distinct antiferroelectric response to electric fields. However, its structure and formation mechanisms remain debated, with flexoelectric and electrostatics effects proposed as competing mechanisms. By controlling the magnitude of electrostatic forces through ion addition in two representative ferroelectric nematic materials, it is shown that the primary mechanism for the emergence of antiferroelectric order is the flexoelectric coupling between electric polarization and splay deformation of the nematic director. The addition of ions significantly expands the temperature range over which the antiferroelectric phase is observed, with this range increasing with increasing ion concentration. Polarizing optical microscopy studies and second harmonic generation (SHG) microscopy reveal the splayed structure modulated in 2D, while SHG interferometry confirms its antiferroelectric character. The model previously used to describe pretransitional behavior is extended by incorporating the electrostatic contribution of ions. The model shows qualitative agreement with the experiments, accurately reproducing the phase diagram and temperature-dependent evolution of the modulation period of the observed structure
Resolving the contrasting leaf hydraulic adaptation of C3 and C4 grasses
Get PDFGrasses are exceptionally productive, yet their hydraulic adaptation is paradoxical. Among C3 grasses, a high photosynthetic rate (Aarea) may depend on higher vein density (Dv) and hydraulic conductance (Kleaf). However, the higher Dv of C4 grasses suggests a hydraulic surplus, given their reduced need for high Kleaf resulting from lower stomatal conductance (gs).
Combining hydraulic and photosynthetic physiological data for diverse common garden C3 and C4 species with data for 332 species from the published literature, and mechanistic modeling, we validated a framework for linkages of photosynthesis with hydraulic transport, anatomy, and adaptation to aridity.
C3 and C4 grasses had similar Kleaf in our common garden, but C4 grasses had higher Kleaf than C3 species in our meta-analysis. Variation in Kleaf depended on outside-xylem pathways. C4 grasses have high Kleaf : gs, which modeling shows is essential to achieve their photosynthetic advantage.
Across C3 grasses, higher Aarea was associated with higher Kleaf, and adaptation to aridity, whereas for C4 species, adaptation to aridity was associated with higher Kleaf : gs. These associations are consistent with adaptation for stress avoidance.
Hydraulic traits are a critical element of evolutionary and ecological success in C3 and C4 grasses and are crucial avenues for crop design and ecological forecasting
Towards developing a “baby translator” - an exploration of how infant appetite cues are understood.
No full textCaregivers’ feeding practices shape their child's eating patterns and subsequent health. Research shows that sensitive feeding is linked to healthy development and self-regulation but depends on caregiver responsiveness to infant needs and appetite cues. Responsive feeding (RF) is influenced both by characteristics of the caregiver and expressiveness of the infant. To investigate how infant communication is understood and whether recognition of appetite cues is associated with the viewer’s eating traits, mental health and wellbeing, an online study was conducted. Participants (N = 200) aged 18 – 55 years were recruited in June 2022 via Prolific. Recognition of infant appetite cues was measured by participant responses to video clips of infants (N = 10) being fed during mealtimes (sampled at the start and end of a meal). Caregiver satiety responsiveness, intuitive eating, alexithymia, autism spectrum disorder, and mental health were assessed by validated questionnaires. Results showed a high consensus in identifying infant appetite cues, with no significant correlations with parenting status, eating traits or mental health, except for one subscale of alexithymia - Difficulty Describing Feelings (r = -.15, p = .03). Open-ended descriptions of mealtime cues showed that positive affect was observed early in the meal and more negative affect at the end of the meal. Infant cues signalling interest in eating were generally well recognised and were not significantly correlated with individual differences of the viewer except alexithymia. Further research to assess the association between alexithymia, responsiveness to infant communication cues and RF practices is warranted
Does tight control of disease impede radiological progression? The radiographic outcomes of the TICOPA study
No full textObjective
The Tight Control of Psoriatic Arthritis (TICOPA) study was the first to undertake the treat-to-target approach in psoriatic arthritis (PsA). Our aim was to further investigate the radiographic changes in the TICOPA study.
Methods
The TICOPA trial recruited patients with early treatment-naïve PsA. Plain radiographs of the hands and feet were taken at weeks 0 and 48. Clinical outcomes were recorded by a blinded assessor every 12 weeks. In post hoc analysis, bootstrapped quantile regression, adjusting for baseline values and minimization factors, was used to compare radiographic scores (modified Sharp/van der Heijde [mSvdH]), defined according to treatment arm or disease activity states.
Results
Paired baseline and week 48 radiographs were available for 169/206 (82%) at week 48 (84 tight control [TC] arm, 85 standard care [StdC] arm). There was no difference in change in total mSvdH score seen with TC compared to StdC (median [IQR] 0.0 [–2.0 to 0.5] vs 0.0 [–2.0 to 0.0]; difference 0.0 [95% CI 0.0-0.0]). Median total mSvdH score change was lower in those achieving minimal disease activity, Disease Activity in Psoriatic Arthritis remission, and very low disease activity. The number of people with radiographic progression (total erosion score of ≥ 2 at week 48) was numerically lower in the TC group (5/84 [5.9%] vs 12/85 [14.1%]). Patients with radiographical progression presented with polyarticular disease and high C-reactive protein, and had poorer clinical outcomes at weeks 12 and 24.
Conclusion
These data confirm the benefit of achieving low disease activity states on subsequent radiographic outcomes but did not show a significant impact related to a TC management approach
Cell-free expression and SMA copolymer encapsulation of a functional receptor tyrosine kinase disease variant, FGFR3-TACC3
Get PDFDespite their high clinical relevance, obtaining structural and biophysical data on transmembrane proteins has been hindered by challenges involved in their expression and extraction in a homogeneous, functionally-active form. The inherent enzymatic activity of receptor tyrosine kinases (RTKs) presents additional challenges. Oncogenic fusions of RTKs with heterologous partners represent a particularly difficult-to-express protein subtype due to their high flexibility, aggregation propensity and the lack of a known method for extraction within the native lipid environment. One such protein is the fibroblast growth factor receptor 3 fused with transforming acidic coiled-coil-containing protein 3 (FGFR3-TACC3), which has failed to express to sufficient quality or functionality in traditional expression systems. Cell-free protein expression (CFPE) is a burgeoning arm of synthetic biology, enabling the rapid and efficient generation of recombinant proteins. This platform is characterised by utilising an optimised solution of cellular machinery to facilitate protein synthesis in vitro. In doing so, CFPE can act as a surrogate system for a range of proteins that are otherwise difficult to express through traditional host cell-based approaches. Here, functional FGFR3-TACC3 was expressed through a novel cell-free expression system in under 48 h. The resultant protein was reconstituted using SMA copolymers with a specific yield of 300 µg/mL of lysate. Functionally, the protein demonstrated significant kinase domain phosphorylation (t < 0.0001). Currently, there is no published, high-resolution structure of any full-length RTK. These findings form a promising foundation for future research on oncogenic RTKs and the application of cell-free systems for synthesising functional membrane proteins
Long term health outcomes in people with diabetes 12 months after hospitalisation with COVID-19 in the UK: a prospective cohort study
Get PDFBackground
People with diabetes are at increased risk of hospitalisation, morbidity, and mortality following SARS-CoV-2 infection. Long-term outcomes for people with diabetes previously hospitalised with COVID-19 are, however, unknown. This study aimed to determine the longer-term physical and mental health effects of COVID-19 in people with and without diabetes.
Methods
The PHOSP-COVID study is a multicentre, long-term follow-up study of adults discharged from hospital between 1 February 2020 and 31 March 2021 in the UK following COVID-19, involving detailed assessment at 5 and 12 months after discharge. The association between diabetes status and outcomes were explored using multivariable linear and logistic regressions.
Findings
People with diabetes who survived hospital admission with COVID-19 display worse physical outcomes compared to those without diabetes at 5- and 12-month follow-up. People with diabetes displayed higher fatigue (only at 5 months), frailty, lower physical performance, and health-related quality of life and poorer cognitive function. Differences in outcomes between diabetes status groups were largely consistent from 5 to 12-months. In regression models, differences at 5 and 12 months were attenuated after adjustment for BMI and presence of other long-term conditions.
Interpretation
People with diabetes reported worse physical outcomes up to 12 months after hospital discharge with COVID-19 compared to those without diabetes. These data support the need to reduce inequalities in long-term physical and mental health effects of SARS-CoV-2 infection in people with diabetes.
Funding
UK Research and Innovation and National Institute for Health Research. The study was approved by the Leeds West Research Ethics Committee (20/YH/0225) and is registered on the ISRCTN Registry (ISRCTN10980107)
Silent registered EU GIs: what is at stake?
Get PDFThe present paper investigates the topic of ‘silent registered Geographical Indications’ (GIs), defined as GIs that after their registration, or nonetheless during a relevant period of time, have fallen into disuse or are employed considerably beyond their expected potential. In particular, by applying an empirical methodology, the research will constitute the first attempt to analyse and measure this phenomenon from an EU perspective, especially, although not exclusively, in the context of Italian GIs. First results highlight the extent of the silent GIs phenomenon and the need for further investigation to understand the reasons behind it. The issue of silent GIs can be tackled from two diverging perspectives: one considers silent GIs as detrimental to the GI system as a whole, while the second argues the need to maintain their protection in view of the prevention of generalisation of GIs and the indirect economic effects they can still play
Data sources:
Access Repository Dashboard
Do you manage Open Research Online? Become a CORE Member to access insider analytics, issue reports and manage access to outputs from your repository in the CORE Repository Dashboard! 👇