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Low-frequency contributions in the radiative efficiencies of HFC-236fa, HFC-245fa and HFC-43-10mee over the 225–298 K temperature range
Full text linkHydrofluorocarbons (HFCs) are used as substitutes for ozone-depleting substances regulated under the Montreal Protocol. While having zero ozone depletion potential, HFCs strongly absorb infrared (IR) radiation, making them potent greenhouse gases. Vibrational modes associated with C–F stretching absorb strongly within the atmospheric window (750–1250 cm−1), contributing substantially to radiative forcing. The low-frequency region (<500 cm−1), which accounts for approximately 16% of the Earth’s thermal emission, has however remained largely unexplored mainly due to instrumental challenges. Here, we present the first experimental measurements of IR absorption cross-sections in the 150–500 cm−1 range for HFC-236fa, HFC-245fa, and HFC-43-10mee — three industrially relevant compounds with high global warming potentials (GWPs). The spectra were recorded at the Rutherford Appleton Laboratory using a high-resolution Fourier-transform infrared (FTIR) spectrometer in the temperature range between 225 and 298 K at resolution of 0.25 cm
. In addition, IR cross section spectra were simulated through quantum chemical (QC) calculations including a non-empirical treatment of anharmonic effects.
From the experimental results, we derived effective radiative efficiencies (EREs) in the low-frequency region of 0.001, 0.005, and 0.003 W m−2 ppb−1 for HFC-236fa, HFC-245fa, and HFC-43-10mee, respectively, and revised global warming potentials over 20-, 100-, and 500-year time horizons. Comparison with values reported in the WMO Ozone Assessment Report 2022 reveals minor differences for HFC-245fa and HFC-43-10mee, whereas their value for HFC-236fa shows a significant overestimation, corresponding to a discrepancy of approximately 360 units in the 100-year GWP. Theoretical predictions reproduced experimental band strengths with an overall average deviation of 4%, confirming the reliability of the computational approach even in the low-frequency region. This indicates that the QC technique is likely to provide reliable estimates for RE and GWP for similar compounds where measurements are not available.
These findings highlight that small variations in the treatment of low-frequency absorptions can propagate into substantial contributions in climate metrics, particularly for long-lived compounds. Overall, this study provides a consistent experimental–theoretical framework for quantifying the radiative forcing of HFCs and similar compounds and reduces current uncertainties in the estimation of their climate-relevant parameters
Far-right against green: the re-emergence of geographically defined voting patterns and the new environment cleavage in Western Europe
Full text linkThis article argues that opposition to environmental protection is key to understanding the development of new voting patterns in Western Europe. We theorize climate change as a collective action problem with diffuse benefits and concentrated costs and develop a range of hypotheses about the ways in which concentrated resistance to climate change measures may be channelled into electoral behaviour. We test our hypotheses using data from the European Social Survey. Our results suggest that the backlash against environmental protection is triggered by the potential ‘losers’ of these processes, contributing to the emergence of a territorial cleavage between green voters residing in metropolitical areas, and far-right voters residing in rural and peripheral areas. Our argument explains the development of new political alliances and highlights the importance of green attitudes for the emergence of societal cleavages
Development of a competency framework for healthcare safety investigators: a modified e-Delphi study
Full text linkBackground:
Systems-based healthcare safety investigation is an important initiative to improve patient safety worldwide. It requires the use of credible methods and approaches by competent investigators. There is currently no empirically developed competency framework for the healthcare safety investigator role. We developed a competency framework for healthcare safety investigators using an empirical research approach.
Method: We used a two-round modified Delphi technique electronically. Two web-based surveys were sent to a panel of experts in healthcare safety investigations in England. The panel rated the relevance of a proposed set of competencies and provided qualitative comments. Strength of agreement was assessed using the interquartile range (IQR), the median and percentage agreement. Participants’ comments were reviewed, with reference to the contemporary healthcare safety literature and practice.
Results: A total of 28 participants completed the round-one survey. In round two, 24 of the 28 participants completed the survey. At the end of the round-two survey, 38 competencies and 82 corresponding descriptors were agreed as relevant with high agreement levels (IQR ≤ 1.25, median ≥ 4, percentage agreement ≥ 70%). These were organised in four domains: 1. Personal qualities, 2. Investigation knowledge and skill application, 3. Effective and compassionate engagement, and 4. Manages investigation lifecycle.
Conclusion: To our knowledge, this is the first empirically derived competency framework specifically focused on the healthcare safety investigator role. The high levels of agreement among participants give credibility to the findings. This competency framework provides an evidence base to inform the scope and requirements of the healthcare safety investigator workforce
Assessing students working on an authentic mock case via an evaluative and reflective report
No full textResponsible leadership: a systematic literature review, theoretical framework, and future research directions
Full text linkThis systematic literature review critically examines recent developments in research on responsible leadership (RL) through a framework that combines the core elements of leadership theory: motive, mode and mindset (MMM) along with their antecedents, decisions, and outcomes (ADO). It covers studies published from 2004 to 2024, drawing from interdisciplinary literature across fifty-three academic journals and 140 articles. The review defines RL as a distinct concept and highlights its influence on the individual- (micro), team- (meso), and macro-organizational and societal levels. It provides an overview of the research domain, focusing on trends in RL research, discussing its definition, and distinguishing it from other leadership theories. Additionally, it outlines key characteristics, moderators, causal mechanisms that reinforce the relationship between RL and long-term organizational outcomes. The review also proposes a framework, illustrative propositions, and potential themes and research questions for further investigation
Aviation meteorology | clear-air turbulence
No full textThe development of the scientific understanding of clear-air turbulence (CAT) as an aviation hazard is described in this article. Topics range from the discovery of CAT during World War II to modern techniques to observe and predict conditions conducive to CAT formation, as well as the role of climate change in increasing CAT occurrence. Important physical processes leading to Kelvin–Helmholtz instability (KHI), a primary producer of CAT, are explained. The frequency of occurrence of KHI is shown to be a maximum near synoptic-scale upper-level frontal zones near jet streams, with mountain waves, and in the vicinity of the tops of severe thunderstorms. Several current physical and statistical approaches to CAT prediction based on this knowledge are described. The impact of climate change on CAT has become an active area of research recently, with evidence that the amount of CAT in the atmosphere has increased over the past few decades, and with projections of further large increases in future
Mulch quality regulates soil fertility and microbial communities during a crop cycle
Full text linkContext
The benefits of plant-based mulch extend beyond improving soil physical properties as mulches hold value as a fertiliser and in maintaining robust soil microbial communities throughout the crop cultivation period.
Aims
We investigated the impact of plant-based mulch quality (comprising contrasting hemicellulose, cellulose, and lignin components) sourced from single and diverse species mixtures on soil fertility, microbial communities, crop yield, and seed quality by growing barley from seed to maturity in rhizotrons.
Methods
The treatments consisted of residue mixtures containing 17, 12, 6, and 1 grassland plant species, as well as wood chips, with a control group receiving no residues. Soil samples were collected at two time points, 69 and 195 days after mulch application, for nutrient and microbial phospholipid fatty acid analysis. Residues were analysed for hemicellulose, cellulose, and lignin content.
Key results
We found that high-quality residues, with low carbon:nitrogen ratio, low recalcitrance, and the highest nitrogen content decomposed most quickly and increased available soil potassium concentrations compared to residues of lower quality. The lower-quality residues retained a greater proportion of their initial fertilisation capacity, which was released gradually. There was a concomitant increase in soil microbial biomass at later stages of decomposition in residues of lower quality. Residue quality significantly affected crop seed quality but not yield.
Conclusions
Lower-quality residues can maintain their fertilisation capacity over a longer time horizon than higher-quality residues. Plant residue mulch can influence soil microbial biomass throughout the cultivation period, regardless of its initial quality, and can affect crop quality although this effect is slow and not always readily detectable.
Implications
These findings emphasise the importance of considering plant-based mulch quality in enhancing soil fertility and crop quality
D-amino acid substitution and cyclization enhance the stability and antimicrobial activity of arginine-rich peptides
Full text linkCationic peptides, particularly those rich in arginine and/or lysine residues, are usually promising antimicrobial agents effective at low concentrations in laboratory settings. However, their applicability in pharmaceutics and biotechnology is currently limited due to their susceptibility to biological enzymatic processes and (in some cases) toxicity to host cells. To address this, we screened eight linear arginine-rich peptides for their haemolytic properties and antimicrobial activity using a set of computational and experimental assays. Inspired by our previous results on R4F4, we then designed three modified peptides based on an R4F4 backbone, R4F4-C16, D-R4F4 and cyclic R4F4, and one based on R4 (R4-C16). Amongst the tested linear peptides containing only natural amino acids, R4F4 exhibited the strongest antibacterial activity; however, this effect was reduced in the presence of human serum and trypsin. Conversely, our study demonstrated that cyclization and substitution to its d-amino acid enantiomer significantly enhanced stability and activity of R4F4, whilst in the presence of proteases. As revealed by fluorescence imaging, microscopy RNA sequencing analysis, the mode of action involves complex and dynamic events. This multifaceted antimicrobial mechanism integrates alterations in membrane permeability, modulation of intracellular reactive oxygen species levels and changes in transcriptomic signature profiles. At the molecular level, notable changes were observed in the bacterial expression of genes associated with metabolic pathways and biological processes. Furthermore, R4F4-derived peptides showed substantial antibiofilm activity in preventing the formation and disruption of mature biofilms, together with good cytocompatibility, highlighting the potential for clinical applicability. In conclusion, this study emphasizes the importance of optimizing the stability of peptide-based antimicrobials, particularly those rich in arginine, and highlights the advantages of incorporating d-amino acids and cyclization for enhanced performance. This information will prove useful in the future design of antimicrobial peptides. In addition, the molecular perspective on peptide-induced gene expression changes, as identified by RNA-seq, broadens our understanding of antimicrobial peptides’ activities and provides a clearer picture of their versatile mechanisms