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Quantifying the response of bankfull channel width to active faulting in the Qianhe Graben on the southwest margin of Ordos Block, China
Full text linkRiver longitudinal profiles have been widely used to quantify the transient landscape response to active faulting, but the fluvial cross-section is often ignored, yet width can also reveal river incision and tectonic activity. Channel width responds to tectonic forcing through flow concentration effects resulting in channel narrowing where vertical incision dominates during uplift acceleration. Here we employ a novel bankfull channel width extraction method using Landsat and ZY-3 satellite images, and SRTM DEM data to evaluate the cross-section landscape response to active faulting in the Qianhe Graben of southwest Ordos, China. Although some areas are difficult to access (e.g., thick Quaternary Loess and vegetation cover), limiting the possibility of measuring river widths in the field, the remote sensing width extraction method provides a complete river width evaluation. Twenty-four rivers known to be responding to ongoing tectonic uplift that drain across normal faults were extracted, and demonstrate that the width tends to be narrower in the footwall of faults. Along strike from north to south, the channel widths varied systematically with the distance to the river source, and the normalized wideness index (kwn) of the rivers also decreases to the southeast. In combination, with the distribution of the widths, kwn, exponential of channel width (b’), the main morphologies of the study area are controlled by the lithologies and faults. Additionally, the peak of unit stream power and boundary shear stress gives a new insight into the location of an active fault in this area and overall suggest that uplift rates are higher along the southern graben margin. In regions of tectonic uplift, channel narrowing and steepening are the main modes of channel morphology adjustment, and the timescale of channel width adjustment is usually much shorter than that of gradient adjustment. All of these observations indicate the river channel widths are tracing fault evolution in Qianhe Graben
Fault tolerant adaptive control under actuator saturation for robot manipulators
No full textIn practice, actuators inherently have natural limitations that are often overlooked by theoretical control strategies, such as bounded output and discrepancies between calculated and actual responses. Consequently, reliable control techniques must be employed to ensure safe and dependable operation. We propose an adaptive control law for global regulation in the case of partial loss of effectiveness due to input faults. The proposed control strategy maintains the system at the desired configuration while accounting for the physical limitations of the actuators. Additionally, it is suitable for dealing with unknown parameters in the vector of gravitational forces, making it robust to these uncertainties. The approach treats the inputs as time-varying signals, allowing for an infinite number of faults. The methodology has the advantage of operating in continuous time. Thus, it is theoretically capable of counteracting any fault event of arbitrary magnitude, as long as the actuators are able to continue overcoming gravitational effects while maintaining inertial and gravitational counteracting responses. The closed-loop system is analyzed using Lyapunov\u27s stability theory for non-autonomous systems, concluding global asymptotic convergence of all signals. The effectiveness of the control strategy is illustrated through simulations that exhibit resilience to degradation in actuator performance
Evaluating blanket mire vegetation recovery following hydrological restoration, with specific focus on the influence of Molinia caerulea
No full textThis thesis evaluates the ecological processes involved in passive blanket peatland vegetation restoration following hydrological rewetting and evaluates the role of Molinia caerulea tussock development as a barrier to blanket mire vegetation establishment. Using data collected from restoration pools and terrestrial peat surfaces across blanket bog habitats on Dartmoor National Park, vegetation responses to rewetting over timescales of up to 10 years were evaluated. Observations were made on the restorative processes of terrestrialisation in pools and paludification of the terrestrial peat surface, and on the role of M. caerulea tussocks in shaping microclimates and vegetation assemblages. Results show that aquatic Sphagnum species had rapid colonisation potential where propagules occur in flow pathways, with 76% of pools containing Sphagnum within 18 months. Sphagnum colonisation and abundance are controlled by pool depth and rainfall consistency, with reduced cover observed as a result of low spring and summer precipitation. Paludification occurs rapidly within three years close to pool edges, but wider establishment is slower. Lawn Sphagnum and associated mire species re-colonise into the dominant dry peat vegetation simultaneously at distances up to 10m from pool edges where the water table is maintained at the near surface within 7-10 years, but plant competition from dominant Molinia caerulea tussocks remains a measurable constraint. M. caerulea tussocks create significant warming and desiccating effects, with larger tussocks and higher densities amplifying temperature and moisture differences. These microclimatic changes further promote M. caerulea preservation and expansion at the expense of Sphagnum and other mire vegetation, particularly in areas of shallow peat where water tables fluctuate. Anthropogenic induced climate change is likely to worsen these effects by further increasing suitability for M. caerulea dominance in the context of upland peatland systems. Interactions between mire vegetation and both hydrology and M. caerulea competition must not be overlooked if we are to effectively manage blanket peatland habitats in a sustainable way. Long-term successful peatland restoration will depend not only on maintaining near-surface water tables but also ensuring connectivity between restoration pools and managing M. caerulea dominance to ensure favourable conditions for aquatic and terrestrial Sphagna
A pre-operative two-week very low-calorie diet to reduce steatosis before liver resection (RESOLVE): A multi-centre randomised controlled feasibility trial
No full textBackgroundLiver surgery (LS) remains the main curative option for liver metastases and primary liver tumours. Low-calorie and very low-calorie diets (VLCDs) are routinely used for 2-4 weeks prior to bariatric and gallbladder surgery to reduce liver size and abdominal adiposity, thereby improving surgical safety. This study aimed to evaluate the feasibility of a VLCD in patients undergoing LS with hepatic steatosis (HS).MethodsIn this randomised controlled feasibility trial, 29 participants were randomised to either the intervention group (VLCD providing 800 kcal and 80 g protein for 2 weeks before LS; n = 14) or treatment as usual (n = 15). Feasibility and clinical outcomes, including operating time, blood loss, ease of surgery, length of hospital stay, readmission and mortality, were assessed.ResultsThere was no indication of a between-group difference. There was no mortality within 90 days. In the intervention group, 11 participants initiated VLCD and 6 adhered to it for at least 10 days.DiscussionAlthough this feasibility study did not demonstrate a clinical benefit due to the small sample size, a definitive trial is needed to evaluate whether a VLCD administered 2 weeks before LS reduces HS during the preoperative period
Pulpal Chamber Floor Thickness of First Molars in a Black South African Sample
No full textBackground/Objectives: Root canal procedures on multi-rooted teeth, including first molars, depend on experience, tactile perception, and anatomical knowledge to avoid perforation in the furcation region. Studies using various methodologies and populations have reported discrepant findings on pulpal floor thickness. No study using micro-computed tomography (Micro-CT), the gold standard, has been conducted on a Black South African sample to evaluate pulpal floor thickness. Methods: In this cross-sectional, descriptive,quantitative study, Micro-CT scans of 91 maxillary and 77 mandibular first molars were reconstructed in 3D and oriented according to a reference plane along the cemento-enamel junction using Avizo software. Measurements were taken from the midpoint of the pulpal chamber floor to the perpendicular point on the furcation. In maxillary molars, an additional measurement between the mesiobuccal and distobuccal roots was taken. The effects of arch, side, age, and sex were assessed. Results: Neither sex, arch, nor side had a significant influence on the pulpal floor thickness. The central mandibular and maxillary pulpal floor thicknesses increased significantly with aging, while the effect on the buccalmaxillary pulpal floor thickness was not significant. The mean central mandibular and maxillary pulpal floor thicknesses were 2.66 and 2.83 mm, respectively, while the buccal maxillary pulpal floor thickness was significantly smaller at 2.37 mm. Conclusions: More accurate and repeatable findings compared to the literature could be attributed to the use of Micro-CT, which provides higher resolution images, and to Avizo, which enables precise localization of 3D points. Variations from the literature might also be explained by differences in the age and geographical origin of the samples
Contingent value of coopetition in business clusters from a resource-based view: A moderated-mediation model
No full textThis study examines how perceived cluster resource attractiveness (PCRA) shapes coopetition among co-located firms and how coopetition translates those resource perceptions into knowledge sharing and innovation. Building on the resource-based view, we model coopetition as the mechanism through which managers leverage valuable, unique, and complementary cluster resources into firm outcomes, and we theorize that engagement mode in cluster activities conditions this translation. Using survey data from 221 firms in a business cluster, we estimate a moderated-mediation model with regression and corroborate the results with a latent-variable SEM robustness check. Findings show that PCRA increases coopetition, and coopetition in turn enhances both knowledge sharingand innovation. However, the indirect effects depend on participation type: formal participation attenuates the coopetition to outcome link, especially for innovation, informal participation is directionally positive but statistically non-significant, and an aggregate participation robustness test confirms attenuation when firms engage in formalized participation. The study introduces PCRA as an operationalization of cluster-level resource heterogeneity, positions coopetition as an RBV-consistent mechanism, and identifies governance-based boundaryconditions limiting the returns to coopetition. Practically, managers should leverage informal ties and selective formal involvement to convert cluster resources into knowledge and innovation while avoiding overformalization that can dampen coopetitive gains
Collaborating with ‘blue food’ system stakeholders to achieve optimal nutritional health and wellbeing in less affluent communities
No full textUK food system transformation is urgently needed, but to date, minimal research has investigated ‘blue foods’ probably because they are ethically nuanced. There exists a paradox whereby materially deprived communities should be eating more fish to meet nutritional requirements, yet there is a global ‘red flag’ around global overfishing. New collaborative and creative solutions are, therefore, needed to tackle such food system inequities. By working together, all voices can be equally heard when decisions are being made to improve the system. Similarly, innovation and disruption of established supply chains will enable better access to healthy, affordable and tasty food that will support better nutrition, health and wellbeing. This review paper will present a critique of the ‘The Plymouth Fish Finger’ as a collaborative social innovation case study. Part of the FoodSEqual research project, this exploratory pilot project championed ‘co-production’ approaches to achieve multiple (potential) impacts. This review will critically explore how this social innovation case study has exemplified the complex interplay between factors driving distortions in access to and availability of fish within the local food system. Through collaborative multi-stakeholder (transdisciplinary) processes, using participatory creative methods, new strategies and recommendations for research, practice, action and policy are informed, all of which offer great potential for progressive and transformative systemic (blue) food system change
Restoration enhances carbon storage in mangroves after hurricane impacts
No full textMangroves are globally important blue-carbon ecosystems, yet their resilience isthreatened by extreme weather events and hydrological alterations. Insoutheastern Mexico, a large mangrove die-off occurred in 1995 followingHurricane Roxanne and Tropical Storm Opal, linked to storm-surge–drivenhypersalinity, sedimentation, and prolonged flooding. In 2005, an ecologicalrestoration program was launched in the Términos Lagoon region, focusing onhydrological rehabilitation and reforestation with Avicennia germinans. Fourteenyears later, we assessed ecosystem recovery by quantifying total ecosystemcarbon stocks (TECS), defined as the sum of 0–50-cm soil organic carbon andtree biomass carbon, across conserved, degraded, and restored sites, and byreconstructing vegetation cover dynamics from multi-decadal satellite imagery(1984–2023). TECS differed markedly among conditions: The restored siteaccumulated 286.0 ± 32.6 Mg C ha−¹ (83% of the conserved site), whereasdegraded sites stored only 133.0 ± 26.8 Mg C ha−¹. The increase in TECS at therestored site was primarily associated with enhanced soil organic carbon stocks,consistent with improved hydroperiod, recovery of interstitial waterphysicochemical conditions, and renewed autochthonous organic matterinputs following hydrological reconnection and initial reforestation. Biomasscarbon remained lower at the restored site, reflecting younger stand age,although vegetation indices indicated rapid canopy recovery within 7 years ofthe intervention. These results show that hydrological rehabilitation cansubstantially re establish long-term carbon storage capacity in hurricane impacted mangroves and highlight the need for sustained monitoring toevaluate ecosystem service recovery and guide climate mitigation and coastalresilience strategies
Organising care for complexity: a pathways model for adult community intellectual disability services
No full textAdult community intellectual disability services in the United Kingdom (UK) are required to deliver specialist, evidence-based care for a variety of conditions while minimising restrictive practices and reliance on inpatient provision. Care pathway models have emerged as a potential mechanism to reconcile these aims yet remain under-used in care philosophies in intellectual disabilities. We propose a generalisable pathways model for community intellectual disability services and examine its implications for policy, clinical practice, and research. The model integrates care navigation, proportionate specialist input, and defined clinical condition care including behaviours that challenge, mental and physical health, forensics, neurodevelopmental conditions, epilepsy, and dementia within a community-based service architecture. It considers recent focus on digitalsation, prevention, workforce and practice innovation. The model aligns with contemporary policy priorities. We argue that pathway-based care delivery provides a pragmatic and ethically grounded framework for organising services. It supports consistency, integration, and preventative care while reducing reliance on reactive risk-based responses. By synthesising service design principles, core pathway functions, and system interfaces, this paper offers a coherent model for contemporary community intellectual disability services. Further empirical evaluation is required to assess the impact of care pathways on outcomes, patient experience, and cost-effectiveness