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Experimental induction of adaptive motivation: Proof of concept
Get PDFObjectiveA study was conducted to determine the effectiveness of an experimental procedure for inducing adaptive motivation, including its differential efficacy for light/moderate and heavy drinkers.MethodParticipants were university-student drinkers (N = 79, males = 26.1%, mean age = 19.86 years) who were randomly assigned to a control or an experimental group. The experimental group underwent an experimental induction involving Concept Identification Cards for enhancing adaptive motivation, whereas the control group received an inert induction. At baseline, all participants completed a demographics questionnaire and the Alcohol Use Questionnaire. To evaluate the effectiveness of the induction, at both baseline and post-induction, participants completed the General Self-Efficacy Scale and the Task-Specific Personal Concern Inventory (TSPCI).ResultsAt baseline, there were no differences between the two groups on Self-Efficacy or Task-Specific Adaptive Motivation. At the posttest, participants in the experimental group correctly answered more of the Concept Identification Cards than the control group ConclusionsThis study demonstrates that adaptive motivational structure can be experimentally induced, and the induction is as effective with Heavy Drinkers as with Light/Moderate Drinkers. Suggestions for future research using the induction of adaptive motivation with heavy drinkers is discussed
Aortic stiffness contributes to greater pressor responses during static hand grip exercise in healthy young and middle-aged normotensive men
Get PDFCentral arterial stiffness can influence exercise blood pressure (BP) by increasing the rise in arterial pressure per unit increase in aortic inflow. Whether central arterial stiffness influences the pressor response to isometric handgrip exercise (HG) and post-exercise muscle ischemia (PEMI), two common laboratory tests to study sympathetic control of BP, is unknown. We studied 46 healthy non-hypertensive males (23 young and 23 middle-aged) during HG (which increases in cardiac output [Q̇c]) and isolated metaboreflex activation PEMI (no change or decreases in Q̇c). Aortic stiffness (aortic pulse wave velocity [aPWV]; applanation tonometry via SphygmoCor) was measured during supine rest and was correlated to the pressor responses to HG and PEMI. BP (photoplethysmography) and muscle sympathetic nerve activity (MSNA) were continuously recorded at rest, during HG to fatigue (35 % maximal voluntary contraction) and 2-min of PEMI. aPWV was higher in middle-aged compared to young males (7.1 ± 0.9 vs 5.4 ± 0.7 m/s, P < 0.001). Middle-aged males also exhibited greater increases in systolic pressure (∆30 ± 11 vs 10 ± 8 mmHg) and MSNA (∆2313 ± 2006 vs 1387 ± 1482 %/min) compared to young males during HG (both, P < 0.03); with no difference in the Q̇c response (P = 0.090). Responses to PEMI were not different between groups. Sympathetic transduction during these stressors (MSNA-diastolic pressure slope) was not different between groups (P > 0.341). Middle-aged males displayed a greater increase in SBP per unit change of Q̇c during HG (∆SBP/∆Q̇c; 21 ± 18 vs 6 ± 10 mmHg/L/min, P = 0.004), with a strong and moderate relationship between the change in systolic (r = 0.53, P < 0.001) and diastolic pressure (r = 0.34, P = 0.023) and resting aPWV, respectively; with no correlation during PEMI. Central arterial stiffness can modulate pressor responses during stimuli associated with increases in cardiac output and sympathoexcitation in healthy males. [Abstract copyright: Copyright © 2023 Elsevier B.V. All rights reserved.
Separating N2O production and consumption in intact agricultural soil cores at different moisture contents and depths
Get PDFAgricultural soils are a major source of the potent greenhouse gas and ozone depleting substance, N2O. To implement management practices that minimize microbial N2O production and maximize its consumption (i.e., complete denitrification), we must understand the interplay between simultaneously occurring biological and physical processes, especially how this changes with soil depth. Meaningfully disentangling of these processes is challenging and typical N2O flux measurement techniques provide little insight into subsurface mechanisms. In addition, denitrification studies are often conducted on sieved soil in altered O2 environments which relate poorly to in situ field conditions. Here, we developed a novel incubation system with headspaces both above and below the soil cores and field-relevant O2 concentrations to better represent in situ conditions. We incubated intact sandy clay loam textured agricultural topsoil (0-10 cm) and subsoil (50-60 cm) cores for 3-4 days at 50% and 70% water-filled pore space, respectively. 15N-N2O pool dilution and an SF6 tracer were injected below the cores to determine the relative diffusivity and the net N2O emission and gross N2O emission and consumption fluxes. The relationship between calculated fluxes from the below and above soil core headspaces confirmed that the system performed well. Relative diffusivity did not vary with depth, likely due to the preservation of preferential flow pathways in the intact cores. Gross N2O emission and uptake also did not differ with depth but were higher in the drier cores, contrary to expectation. We speculate this was due to aerobic denitrification being the primary N2O consuming process and simultaneously occurring denitrification and nitrification both producing N2O in the drier cores. We provide further evidence of substantial N2O consumption in drier soil but without net negative N2O emissions. The results from this study are important for the future application of the 15N-N2O pool dilution method and N budgeting and modelling, as required for improving management to minimize N2O losses.</p
Optimising sustainability: Circular pathways for Scotch Whisky distillery co-products
Get PDFThe use of co-products for animal feed can potentially have a higher greenhouse gas (GHG) emission and water scarcity offset compared to bio-energy (bio-electricity/fuel) production. We cluster 136 Scotch Whisky distilleries and evaluate the co-product pathways for the production of animal-feed and/or bio-energy at centralised processing facilities. Production of animal feed, and the subsequent displacement of imported animal feed, offered the most significant GHG offset, which was between a factor of c.a. 2.5 to 8 times greater than the bio-electricity/fuel and bio-energy/feed scenarios. This offers significant potential from a global net-zero carbon emissions perspective. However, this comes at a cost to local energy security potential. Bio-electricity produced in the electricity intensive scenarios was 481 GWh per year. This would significantly increase Scotland's bio-energy production and equates to c.a. 5% of Scotland's non-commercial electricity needs
Investigating the neurocognitive bases of social cognition from a general semantics perspective
Get PDFThe Effects of Changing Livestock Practices on the Breeding Performance of the Common Raven, <i>Corvus corax</i>, in Northwest Wales
Get PDFComparing relationships between single types of adverse childhood experiences and health-related outcomes: a combined primary data study of eight cross-sectional surveys in England and Wales
Get PDFObjectives Adverse childhood experiences (ACEs) show strong cumulative associations with ill-health across the life course. Harms can arise even in those exposed to a single ACE type but few studies examine such exposure. For individuals experiencing a single ACE type, we examine which ACEs are most strongly related to different health harms.Design Secondary analysis of combined data from eight cross-sectional general population ACE surveys.Setting Households in England and Wales.Participants 20 556 residents aged 18–69 years.Measures Ten self-reported outcomes were examined: smoking, cannabis use, binge drinking, obesity, sexually transmitted infection, teenage pregnancy, mental well-being, violence perpetration, violence victimisation and incarceration. Adjusted ORs and percentage changes in outcomes were calculated for each type of ACE exposure.Results Significance and magnitude of associations between each ACE and outcome varied. Binge drinking was associated with childhood verbal abuse (VA), parental separation (PS) and household alcohol problem (AP), while obesity was linked to sexual abuse (SA) and household mental illness. SA also showed the biggest increase in cannabis use (25.5% vs 10.8%, no ACEs). Household AP was the ACE most strongly associated with violence and incarceration. PS was associated with teenage pregnancy (9.1% vs 3.7%, no ACEs) and 5 other outcomes. VA was associated with 7 of the 10 outcomes examined.Conclusion Exposure to a single ACE increases risks of poorer outcomes across health-harming behaviours, sexual health, mental well-being and criminal domains. Toxic stress can arise from ACEs such as physical and SA but other more prevalent ACEs (eg, VA, PS) may also contribute substantively to poorer life course health
Bioplastic (PHBV) addition to soil alters microbial community structure and negatively affects plant-microbial metabolic functioning in maize
Get PDFMicroplastic contamination poses a significant threat to agroecosystem functioning, provoking a move away from the use of conventional oil-based plastics in agriculture, to biodegradable alternatives that may be degraded over a shorter timescale. The impact of these bioplastics on plant and soil health, however, has received relatively little attention. Here, we investigated the effect of soil loading (0.01%, 0.1%, 1% and 10%) of biobased microplastic poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) on soil and plant (Zea mays L.) health and function. We showed that PHBV caused a dose-dependent reduction in plant growth and foliar nitrogen (N) content while untargeted metabolite analysis revealed significant shifts in foliar metabolic function. These results were also reflected in soil, where PHBV led to reduced plant availability of both ammonium and nitrate. Soil 14C-isotope tracing and 16S metabarcoding revealed that PHBV suppressed microbial activity, reduced bacterial diversity and shifted microbial community structure, inducing a major shift in soil metabolic pathways, and thus functioning. Overall, our data suggests that the bioplastic PHBV is not environmentally benign and that contamination levels as low as 0.01% (0.01 mg kg-1) can induce significant short-term changes in both plant and soil microbial functioning, with potential implications for long term agroecosystem health
