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The blood-sucking tick Ixodes hexagonus reveals dietary stable isotope signatures of mammalian hosts
Get PDFTicks are obligate haematophagous ('blood-sucking') ectoparasites that are capable of retaining host dietary traces post-moult, providing an opportunity to investigate parasite-host interactions and explore their potential as non-invasive subsampling techniques. However, research on the preservation of biochemical host signatures within whole engorged parasites remains limited. Here, we examine stable isotope ratios of nitrogen (δ15N) and carbon (δ13C) across different tick tissues (exoskeleton vs. blood meal) and between whole ticks and one of their hosts, the European polecat Mustela putorius. Additionally, carbon and nitrogen weight percentages (wt%) are assessed to explore potential biochemical changes linked to blood meal digestion. Our findings showed that the isotopic composition of tick exoskeleton and blood meal differed significantly, with exoskeletons potentially reflecting a previous host. Whole engorged ticks showed a close δ15N relationship to their host, consistent with that of trophic enrichment, while the observed δ13C values were more variable. These findings enhance our understanding of how haematophagous parasites preserve host dietary signatures and, with further research, could support their use as a valuable alternative to invasive sampling methods, particularly when destructive sampling is not feasible
Forecast error growth: a dynamic–stochastic model
No full textThere is a history of simple forecast error growth models designed to capture the key properties of error growth in operational numerical weather prediction (NWP) models. We propose here such a scalar model that relies on the previous ones and incorporates multiplicative noise in a nonlinear stochastic differential equation (SDE). We analyze the properties of this SDE, including the shape of the error growth curve for small times and its stationary distribution, and prove well-posedness and positivity of solutions. Next, we fit this model to operational NWP error growth curves and show good agreement with both the mean and probabilistic features of the error growth. These results suggest that the dynamic–stochastic error growth model proposed herein and similar ones could play a role in many other areas of the sciences that involve prediction
Technology-enhanced vocabulary learning: the role of self-regulation and prior knowledge
Get PDFTechnology-enhanced vocabulary learning has gained increasing attention, yet its effectiveness remains inconclusive, with studies reporting mixed findings. Additionally, whether integrating self-regulated learning mechanism (SLM) into such type of learning can further enhance its effectiveness remains underexplored. This study examines the impact of two approaches, digital flashcards (DF) and video enhancement (VE), with and without SLM on vocabulary learning. It also investigates how pre-existing vocabulary knowledge (PVK) and self-regulation moderate these effects. Conducted with 132 junior high Chinese EFL learners over six weeks, pre- and post-tests measured written and aural form recognition and meaning recall across four experimental conditions and a control group. Results indicated that all interventions significantly improved vocabulary learning, with VE outperforming DF. The SLM was effective for supporting form recognition, particularly in VE, but its effectiveness diminished for the more demanding task of meaning recall. Self-regulation did not moderate learning outcomes, but PVK did for meaning recall within DF. Higher PVK learners benefited more from additional SLM, as it allowed them to integrate prior knowledge, whereas learners with limited PVK preferred DF alone. These findings highlight the need to align technology-enhanced vocabulary learning with task complexity and individual differences, offering practical insights for more adaptive instructional design
Effect of processing on the composition, structure and digestibility of cow’s milk protein
Get PDFMilk provides essential nutrients and serves as an energy source in our diet. The quality of protein in milk is closely linked to its nutritive value, which reflects its ability to support key metabolic functions essential for optimal health. Important aspects of dietary protein quality include amino acid composition, protein digestibility, and amino acid bioavailability. Before consumption, commercial milk undergoes various processing methods for safety and improving shelf-life, which can significantly alter its nutritional protein value. Processing techniques may impact the nutritional quality of milk proteins, either positively or negatively. Given the necessity of processing, it is essential to manage these methods carefully to preserve the protein functionality and nutritional value of milk, especially as it is a core component of many healthy and functional foods and beverages. Microfiltration of fresh milk is a relatively new commercial process designed to extend its shelf life in combination with pasteurisation. The aim of this study is to expand our understanding of the effects of microfiltration on milk proteins. This work could facilitate research and development of food products containing milk protein as a crucial nutritional component, as well as improve processing methods to optimize milk protein attributes. This thesis specifically addresses changes in protein structure, digestibility, and peptide profiles in commercially available filtered milk in the UK market, in comparison to pasteurized milk. By 2024, the production of filtered semi-skimmed milk had increased by about 25 %, representing 83 % of the brands available in the UK market, according to the data collected in this study. Meanwhile, filtered whole milk saw a 58 % increase, now comprising approximately 66 % of brands that sell fresh milk, as observed in this research. The combination of particle size measurements, thiol content analysis, and Confocal Laser Scanning Microscopy (CLSM) provided a comprehensive understanding of how microfiltration influences milk's structural properties in comparison to pasteurisation. A significant increase in Z-average particle size (average ~+12 %) and reduction in thiol content (average ~-24 %) indicate that filtration promotes the formation of larger aggregates, potentially through thiol-disulphide exchange interactions. CLSM imaging further revealed enhanced protein-fat interactions in filtered milk, suggesting a strengthened association between milk proteins and fat globule membrane proteins. Protein digestibility and peptides released after in vitro digestion were analysed by examining the static in vitro gastrointestinal digested milk samples using high-resolution quadrupole time of flight instruments (TOF LC/MS). Although no significant differences were observed in the in vitro gastrointestinal digestion between filtered and pasteurised milk, notable changes in peptide distribution were identified. These variations suggest that the filtration process may influence the types or quantities of peptides released. First, β-casomorphin 7 (BCM7), is an opioid peptide released during the digestion of β-casein, which has been associated with various health concerns, was measured in filtered and pasteurised samples following the in vitro digestion. Interestingly, the presence of fat appears to limit BCM7 release and has a greater impact on BCM7 release than microfiltration alone, suggesting that fat content may play a more prominent role in moderating bioactive peptide release. Microfiltration appears to influence BCM7 release more significantly when fat is present. In semi-skimmed filtered milk, quantification of BCM7 revealed no significant difference in levels compared to pasteurised milk, though correlations between fat content, processing methods, and protein digestion percentages highlighted distinct impacts of microfiltration. Comparing the percentage increase in BCM7 release between filtered and pasteurized milk of the same fat content (indicating the effect of processing) and between semi-skimmed and whole milk under the same process (indicating the effect of fat content) provides clearer insight into how these factors individually affect BCM7 production. This finding warrants further investigation to understand the mechanisms behind these differences in protein structure and peptide distribution and their potential implications for milk's bioactivity and nutritional properties
UK air quality showed clear improvement from 2015 to 2024 but breaching of targets remains very common
Get PDFThe impact of poor air quality (AQ) on public health has long been recognised and considerable efforts have been made to improve it across the UK. The UK has a far reaching AQ monitoring network and this study summarises the evolution of UK AQ over the period 2015–2024, focusing on the pollutants NO 2 , O 3 and PM 2 . 5 and exploring their drivers. Concentrations of NO 2 and PM 2 . 5 exhibit robust negative trends across the whole country while concentrations of O 3 increase. Comparing 2015–2016 to 2023–2024, the median number of days per year for which DEFRA AQ sites breached the WHO 2021 target decreased from 136 to 40 (−70%) for NO 2 and from 60 to 22 (−63%) for PM 2 . 5 . This trend was mirrored in other AQ monitoring networks and highlights that, while progress is being made, acceptable levels of AQ are yet to be reached. Over the same period, median O 3 exceedances increased from 7 to 14 days per year. Nationwide analysis of diurnal variation in the pollutants and the use of airmass back trajectory clustering and statistical modelling for three locations – Reading, Sheffield and Glasgow – suggests that local traffic plays a dominant role in NO 2 pollution, PM 2 . 5 is influenced more by long range transport and O 3 increases are being driven in part by decreases in NO 2 . From an AQ policy perspective, this suggests continued focus on traffic emissions will reduce NO 2 , (inter)national rather than local efforts are most critical for PM 2 . 5 improvements, and reductions to VOC emissions must accompany NO 2 if further O 3 increases are to be avoided
How mycorrhizal fungi could extend plant cognitive processes
Get PDFTraditionally, mycorrhizas are studied for their role in plant health and nutrition through a mutually beneficial exchange of solutes. Recent research has revealed additional roles for mycorrhizas, including shaping plant communities and enhancing stress resistance. However, a critical aspect for the survival of organisms remains largely ignored in the study of mycorrhizal symbioses: cognition. This review explores the possibility that plants benefit from the cognition and behaviour of mycorrhizal fungi to enhance their own survival. We examine four case studies that are suggestive of plants extending their cognition through mycorrhizal associations: i) foraging complementarity between roots and mycorrhizal fungi; ii) recruitment and abandonment of mycorrhizal fungi depending on the host plant nutritional status; iii) expanded perception of the belowground environment; and iv) shaping the mycorrhizal community to meet survival needs. Whilst extended plant cognition is implied, direct experimental evidence corroborating this hypothesis is needed, and we propose a delimiting criterion with suggestions of experiments to test this hypothesis
Backlot connections
Get PDFThe video essay investigates the standing sets of the Universal Studios Backlot. The reuse and adaptation of such sets is a pragmatic reality of production but sometimes the relationships between spaces, through time and project, become suggestive or surprising in the meanings and experiences they produce. Drawing on films made or set in the 1950s, the video maps the artificial geography of a small town, encountering characters from different stories and genres, drawing out overlooked and uncanny links between films shot in the same or neighbouring spaces
Constructive engagement in cognitive stimulation therapy groups among people with dementia: a mixed‐methods study
Get PDFIntroduction: Clinical guidelines recommend personalized activities and group cognitive stimulation therapy (CST) for promoting cognition, independence, and well‐being in persons with dementia. Constructive engagement (CE), the state of being occupied positively in purposeful activities, is theoretically an essential process in personalized activities and CST. However, whether CE develops over time and what contributes to it are unknown. We investigated changes in CE during CST and its contributors. Methods: This is a mixed‐methods study. We used time sampling to record the time proportion of persons with dementia (n = 113) spent in constructive, passive, non–task‐related engagement and non‐engagement during early, middle, and late phases in a 14‐session group CST. We tested changes in time proportion between phases using repeated analysis of variance (ANOVA). We analyzed qualitative interviews of CST facilitators (n = 12) thematically to explore contributors to CE. Results: Persons with dementia spent 51% and 46% of their time in constructive and passive engagement, respectively. Time of engagement in non–task‐related activities and non‐engagement was minimal. CE remained stable at around 50% of activity time throughout the intervention course, except for a slight increase from the early to middle phase (48% to 55%, F (2224) = 3.779, p < 0.05). Age (r = −0.26, p < 0.01), cognitive function (r = −0.29, p < 0.01), and activities of daily living (r = 0.20, p < 0.05) at baseline were significantly correlated with CE, but gender and education were not. Contributors to CE include (1) tailoring activities, (2) using group dynamics, and (3) promoting positive experiences. Discussions: Group CST engages persons with dementia well, regardless of their differences in gender and literacy levels. CE remained relatively stable during CST, and younger, more physically and cognitively able people showed slightly greater CE. In group‐based interventions, facilitators' skills and techniques could enhance CE. Future studies may focus on how CE as a plausible change mechanism further improves the intervention outcomes of persons with dementia. Highlights: Cognitive stimulation therapy (CST) is a non‐pharmacological intervention that involves group‐based activities and exercises to improve cognition and quality of life for persons with dementia, but the specific mechanisms behind it are not yet fully understood. This study is the first to investigate constructive engagement (CE), which describes active involvement in meaningful activities or complex interventions, specifically CST, for persons with dementia. CST engages them well, regardless of gender and literacy differences. CE time increases at the early intervention phase and stabilizes later on. CE occupies around half of the intervention time throughout CST, which can still be further increased by activity design and facilitators' skills
Spatiotemporal variations of temperature in Jupiter’s upper atmosphere
Get PDFGlobal temperatures in Jupiter's upper atmosphere are poorly constrained. Other than an in situ measurement by the Galileo Probe, all temperature data come from remote-sensing methods that primarily rely on emissions from H3+, the dominant molecular ion in giant planet ionospheres. While H3+ temperature serves as a proxy for thermospheric temperature under specific conditions, the available H3+ observations at Jupiter have limited spatial coverage and a wide range of reported temperatures that complicate analysis of atmospheric temperatures. We present high-resolution H3+ temperature maps near local solar noon collected over 3 half-nights in 2022 and 2023. Pole-to-pole temperature structure is consistent across time spans of 1 month to 1 yr. Median equatorial (±25° latitude) temperature across all three nights is 762 ± 43 K, with night-to-night differences of <75 K. Temperatures within the statistical locations of the northern and southern auroral ovals are 1200 ± 96 K and 1143 ± 120 K, respectively. A region ∼30 K cooler than its surroundings is found near 20° N, 90° W System III longitude, roughly coincident with a magnetic field anomaly, providing additional evidence for magnetic influence on Jupiter's upper atmosphere. Temperatures generally decrease smoothly from auroral to equatorial latitudes, consistent with the expected gradient if Jupiter's nonauroral latitudes are heated primarily by dynamical redistribution of auroral energy
Government spending reallocations and inequality: evidence from middle-income countries
Get PDFWe assess the impact of spending reallocations on inequality in a fiscally-neutral scenario for a sample of 51 middle-income countries over the period between 2005 and 2015. This is relevant given that developing countries that aim to address increasing inequalities cannot easily rely on either deficit and debts nor increased revenues to finance social spending sectors, such as education, health and social protection. We also look at the impact on different parts of the income distribution and at the role of the Great Financial Crisis of 2007-08. Overall, we find that reallocations to the education sector are associated with a reduction in income inequality. These benefit all subgroups across the population, including the poor and the relatively rich within a country’s income distribution. Reallocation of spending in favour of health, social protection and agriculture are more nuanced and less generalised across the sample of countries. We therefore conclude that greater consideration should be given to the redistributive effects of government budget reallocations than is typically the case