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Willow silvopastoral systems as a strategy to reduce methane emissions while maintaining cattle performance
Get PDFWillow (Salix sp.) is a common tree used in agroforestry for biofuel production and contains condensed tannins (CTs). This study investigated, for the first time, the feasibility of using willow grazing in a silvopastoral system to improve ruminant productivity while minimizing environmental impact. The specific objectives were to: a) characterise willow’s CTs, and b) explore their effect on methane emissions and animal performance. Twenty growing castrated beef cattle (steers) were used in a two-treatment study comparing grazing systems: a willow fodder mix with a grass understory (WFG) and perennial ryegrass grazing (PRG). The study was conducted using a two-period Latin square design. Steers grazing on WFG had an average daily CT intake of 617 g/d. For CTs, the mean degree of polymerisation was 10.6, and the ratio of procyanidin to prodelphinidin was 28.9:71.2. No significant differences were observed between the two treatments in metabolisable energy intake (P=0.0728), nitrogen intake (P=0.844), forage dry matter intake (P=0.100), or total dry matter intake (P=0.0591). A 27% reduction in methane production was observed for the WFG treatment relative to PRG (P<0.001; 173 vs. 273 g/d). This study is the first to provide evidence of the significant potential that willow could have in sustainable livestock production systems worldwide
Do major corporate customers deter supplier misconduct?
No full textWe examine whether major corporate customers can deter misconduct among their suppliers. Our findings indicate that firms with concentrated customer bases are less likely to commit misconduct and face lower penalties in equilibrium. We also observe a significant decline in supplier misconduct following the establishment of a major customer relationship. Furthermore, the deterrent effect of major customers is more pronounced when customer pressure to reduce supplier misconduct risk is higher. Additional analyses suggest that major customers exercise their exit option to penalize suppliers after acute violations. Overall, our results suggest that major customers play a crucial role in deterring supplier misconduct
Acute effects of an anthocyanin-rich blackcurrant beverage on markers of cardiovascular disease risk in healthy adults: a randomized, double-blind, placebo-controlled, crossover trial
Get PDFBackground: Epidemiological evidence suggests an inverse association between anthocyanin consumption and cardiovascular disease (CVD) risk. Modulation of vascular function and hemostasis may contribute to this, but there is limited clinical evidence.
Objective: The present study investigated the acute effects of an anthocyanin-rich blackcurrant beverage, compared with a matched placebo, on selected markers of CVD risk in healthy middle-aged subjects in response to a high-fat meal.
Methods: Twenty-three volunteers aged 39.9 ± 8.1 years (BMI 22.9 ± 2.3 kg/m2) completed a double-blind, randomized, placebo-controlled, crossover trial. Volunteers consumed either 200 mL blackcurrant beverage (744 mg polyphenols comprising 711 mg anthocyanins and 32 mg procyanidins) or a placebo, together with a high-fat breakfast (52.3 g fat) followed by a lunch (30 g fat) at 3 h, and the postprandial vascular response was compared. The primary endpoints were the assessment of vascular function by flow-mediated dilation (FMD) and the inhibition of collagen- and adenosine diphosphate-induced platelet aggregation. Secondary outcomes included blood pressure (BP), digital volume pulse waveforms, circulating numbers of endothelium- and platelet-derived extracellular vesicles (EVs), plasma concentrations of interleukin (IL)-8, and plasma and urinary concentrations of polyphenols and their metabolites were also evaluated.
Results:
There was a significant cumulative improvement in FMD following consumption of an anthocyanin-rich blackcurrant beverage compared with a matched placebo in conjunction with a high-fat meal over a 6 h postprandial period. There was a trend for an inhibitory effect of the blackcurrant beverage on agonist-induced platelet aggregation and significant effects on the secondary outcomes, SBP and IL-8, although these were exploratory and not adjusted for multiple testing. Plasma concentrations of hippuric acid and isovanillic acid were strong independent predictors of FMD and 4-hydroxybenzaldehyde and isoferulic acid glucuronide were predictors of SBP and DBP.
Conclusions: An anthocyanin-rich blackcurrant beverage mitigated the effects of a high fat meal on vascular function and markers of CVD risk, and this is associated with the appearance of specific plasma anthocyanin phenolic metabolites
A molecular toxicological study to explore potential health risks associated with ultrafine particle exposure in cold and humid indoor environments
Get PDFEnvironmental pollutants including ultrafine particulate matter (UFPs) and adverse meteorological conditions pose significant public health impacts, particularly affecting respiratory health. This study aims to elucidate the synergistic effects of cold-humid conditions and UFPs exposure on respiratory health, utilizing Carbon Black Nanoparticles (CB-NPs) as surrogates for UFPs. Through comprehensive lung function tests, histopathological examinations, and biomarker analyses, this research focuses on the modulation of oxidative stress signaling pathways and NF-κB activation. Male Balb/c mice were exposed to specific concentrations of CB-NPs (30-50 nm in diameter, 0.184 mg/(kg·day)) in a controlled environmental chamber mimicking cold (10°C/14°C) and humid (90% RH) conditions over three weeks. The results indicate that exposure to CB-NPs alone increased lung function, oxidative stress (ROS, GSH, MDA), inflammation (IL-6, TNF-α, IL-1β), apoptosis (Caspase 3, Caspase 8, Caspase 9), and histopathological alterations in lung tissue. Furthermore, these effects were notably more severe under combined exposure with cold-humid conditions. These results suggest that the adverse effects of pollutants are not solely concentration-dependent but are exacerbated by specific environmental contexts. It is evident that Vitamin E (100 mg/kg/day) can attenuate these adverse effects, underscoring its potential as a protective agent against environmental stressor-induced air pollutants and cold humid conditions. Our findings suggest that the synergistic effects of environmental factors and pollutant exposure significantly impact respiratory health, providing valuable insights for the design of healthier indoor environments and the development of strategies to mitigate these risks
Developing risk-based approaches to modelling phosphorus contamination in agricultural catchments
Get PDFBayesian Belief Networks (BBNs) are a promising but underutilized probabilistic graphical tool for
modelling water quality for Environmental Impact Assessment, with their ability to include uncertainty
in the predictions being relevant to catchment and water managers. This thesis explores the application
of these tools to predict phosphorus (P) losses in terms of total reactive phosphorus (TRP)
concentrations in four Irish agricultural catchments, with high P concentrations being a major concern
in at least three of them. A hybrid Bayesian Belief Network combining discrete and continuous variables
was developed for a surface hydrology-dominated grassland catchment, using daily concentration data
to build the BBN priors and assess model performance. The step-wise introduction of different P
sources, combined with high-frequency data and detailed catchment understanding improved the first
model iteration’s predictive ability. In all model applications, the models’ predictions presented wider
distributions than the observations, which was noted in similar work, and remains a property of BBNs.
Transferring the BBN across catchments allowed testing the model’s structural uncertainty and showed
that the developed BBN could perform well in surface-driven catchments. The BBN was enhanced by
improved process representation and catchment-specific parameterization. Model transferability across
catchment typologies (surface vs groundwater-dominated, grassland vs tillage land use) is explored,
and the BBNs are used to predict future P concentrations under climate change scenarios. The
application of the catchment-specific BBNs to predict future P concentrations under climate change
revealed the need for further BBN sensitivity analysis to aid result interpretation. The potential for
BBNs to be used as a tool to inform compliance with regulatory standards is discussed. The discussion
considers learnings from current BBN research, P processes represented in both BBNs and process-based models, and the model application in this study. Limitations of the approach and future research
avenues are explored
ENSO-induced latitudinal variation of the subtropical jet modulates extreme winter precipitation over the Western Himalaya
Get PDFIn this study, we investigate the complex relationship between western disturbances (WDs), the El Niño–Southern Oscillation (ENSO), and extreme precipitation events (EPEs) in the western Himalaya (WH) during the extended winter season (November–March). WDs west of WH coincide with 97% of recorded EPEs, contributing substantially (32% in winter, 11% annually) to total precipitation within WH. WDs are 6% less frequent and 4% more intense during El Niño than La Niña to the west of WH. During El Niño (compared to La Niña) years, WDs co-occurring with EPEs are significantly more intense and associated with 17% higher moisture transport over “WH box” (the selected region where most of the winter precipitation over WH occurs). This results in twice the EPE frequency during El Niño periods than La Niña periods. A substantial southward shift (∼180 km) of the subtropical jet (STJ) axis during El Niño brings WD tracks further south towards their primary moisture sources, especially the Arabian Sea. We have shown that WDs that are both more intense and pass to the south of their typical latitudes have higher levels of vertically integrated moisture flux (VIMF) within them. VIMF convergence in the most intense pentile of WDs is 5.7 times higher than in the weakest, and is 3.4 times higher in the second lowest latitude pentile than in the highest. Overall, this study demonstrates a direct link between changes in the latitudinal position and intensity of WDs associated with the winter STJ, and moisture convergence, which leads to the occurrence of EPEs over WH during ENSO phases
Mediating digital literacies across transnational refugee networks: language and resilience inside and outside Syria
Get PDFThe challenges encountered by refugees in resource-low settings has led to increased calls for new approaches to understanding the role of digital literacies in enhancing resilience by building on the experiences of refugees in the Global South. Moreover, there have been repeated calls from within academic circles and the humanitarian sector for more inclusive approaches which de-centre outsider assumptions about refugees’ lived experience. This paper addresses these gaps in the current landscape of migration studies with an account of refugee-led participatory research with a focus on how language as a source of capital is used to enhance resilience across refugee networks when mediating health literacies. Drawing on concepts from critical multilingualism which deconstruct and decentre otherwise privileged language practices, the study illustrates how refugee family members outside Syria mediate complex health literacies as part of their everyday digital literacies for non-refugee members inside Syria, thereby enhancing the resilience of transnational family members across the network. The findings reveal how refugee-led research is best facilitated when refugees’ own language practices are a priority in research design. Working in this way illustrates how research teams negotiate power relations in their research by foregrounding research dynamics and structural hierarchies within interdisciplinary research
Species‐habitat networks reveal conservation implications that other community analyses do not detect
Get PDFGrassland restoration is an important conservation intervention supporting declining insect pollinators in threatened calcareous grassland landscapes. While the success of restoration is often quantified using simple measures of diversity or similarity to target communities, these measures do not capture all fundamental aspects of community reconstruction. Here, we develop species–habitat networks that aim to define habitat-level foraging dependencies of pollinators across restored grassland landscapes and compare their value to these more conventional measures of community restoration. We assessed this across Salisbury Plain (UK), which represents the largest area of chalk grassland in northwestern Europe, encompassing six distinct management types aimed at the restoration and maintenance of species-rich calcareous grassland. Sites that were previously disturbed or reverting from arable agriculture were comparable with those of ancient grasslands in terms of pollinator abundance and species richness. However, intensively managed grasslands exhibited notably lower values across nearly all measured indicators, including flower and pollinator richness and abundance, than ancient grasslands, with unmanaged grasslands following closely behind. This underscores the need for caution with both long-term neglect and highly intensive management. Applying our species–habitat network approach, we found that pollinator communities in grasslands recovering from past military disturbance showed stronger modular associations with those in ancient grasslands than areas recovering from intensive agriculture. This highlights the importance of habitat history in shaping restoration trajectories. We propose that species–habitat networks should be part of the standard analytical toolkit assessing the effectiveness of restoration at landscape scale, particularly for mobile species such as insects
Sample size matters when estimating test-retest reliability of behaviour
Get PDFIntraclass correlation coefficients (ICCs) are a commonly used metric in test-retest reliability research to assess a measure’s ability to quantify systematic between-subject differences. However, estimates of between-subject differences are also influenced by factors including within-subject variability, random errors, and measurement bias. Here, we use data collected from a large online sample (N=150) to: 1. Quantify test-retest reliability of behavioural and computational measures of reversal learning using ICCs. 2. Use our dataset as the basis of a simulation study investigating effects of sample size on variance component estimation, and the association between estimates of variance components and ICC measures. In line with previously published work we find reliable behavioural and computational measures of reversal learning, a commonly used assay of behavioural flexibility. Reliable estimates of between-subjects, within-subjects (across-session), and error variance components for behavioural and computational measures (with ± .05 precision and 80% confidence) required sample sizes ranging from 10 to >300 (behavioural median N: between-subjects=167, within-subjects=34, error=103; computational median N: between-subjects=68, within-subjects=20, error=45). These sample sizes exceed those often used in reliability studies, suggesting larger sample sizes than are commonly used for reliability studies (circa 30) are required to robustly estimate reliability of task performance measures. Additionally, we found that ICC estimates showed highly positive and highly negative correlations respectively with between-subject and error variance components as might be expected, which remained relatively stable across sample sizes. However, ICC estimates were weakly or not correlated with within-subjects variance, providing evidence for the importance of variance decomposition for reliability studies
Doing cybersecurity at home: a human-centred approach for mitigating attacks in AI-enabled home devices
Get PDFAI-enabled devices are increasingly introduced in the home context and cyber-attacks targeting their AI component are becoming more frequent. Moving away from seeing the user as the problem to recognising the user as part of the solution, our research reports on a novel cybersecurity intervention (comprising Explainable AI features, assisted remediation) designed to support users to identify, diagnose and mitigate cyber-attacks on the AI component of their smart devices. We carried out a case study of a bespoke smart heating device inclusive of this intervention and conducted fieldwork with ten households who experienced simulated integrity cyber-attacks over a month. Our research contributes an understanding of how to design AI-enabled devices and their ecosystems to support users to perceive integrity cyber-attacks, offering new considerations for intervention
design that exploits multimodal indicators and supports users to troubleshoot themselves the causes as well as actions of cyber-attacks. Contributing to the growing area of human-centred cybersecurity, we evidence the distinctive challenges users face when evaluating integrity attacks on the AI component in the home context