3,688 research outputs found
Normal fault growth and linkage in the Gediz (Alasehir) Graben, Western Turkey, revealed by transient river long-profiles and slope-break knickpoints
The Gediz (Alaşehir) Graben is located in the highly tectonically active and seismogenic region of Western Turkey. The rivers upstream of the normal fault-bounded graben each contain a non-lithologic knickpoint, including those that drain through inferred fault segment boundaries. Knickpoint heights measured vertically from the fault scale with footwall relief and documented fault throw (vertical displacement). Consequently, we deduce these knickpoints were initiated by an increase in slip rate on the basin-bounding fault, driven by linkage of the three main fault segments of the high-angle graben bounding fault array. Fault interaction theory and ratios of channel steepness suggest that the slip rate enhancement factor on linkage was a factor of 3. We combine this information with geomorphic and structural constraints to estimate that linkage took place between 0.6 Ma and 1 Ma. Calculated pre- and post-linkage throw rates are 0.6 and 2 mm/yr respectively. Maximum knickpoint retreat rates upstream of the faults range from 4.5 to 28 mm/yr, faster than for similar catchments upstream of normal faults in the Central Apennines and the Hatay Graben of Turkey, and implying a fluvial landscape response time of 1.6 to 2.7 Myr. We explore the relative controls of drainage area and precipitation on these retreat rates, and conclude that while climate variation and fault throw rate partially explain the variations seen, lithology remains a potentially important but poorly characterised variable
Ecological IVIS design : using EID to develop a novel in-vehicle information system
New in-vehicle information systems (IVIS) are emerging which purport to encourage more environment friendly or ‘green’ driving. Meanwhile, wider concerns about road safety and in-car distractions remain. The ‘Foot-LITE’ project is an effort to balance these issues, aimed at achieving safer and greener driving through real-time driving information, presented via an in-vehicle interface which facilitates the desired behaviours while avoiding negative consequences. One way of achieving this is to use ecological interface design (EID) techniques. This article presents part of the formative human-centred design process for developing the in-car display through a series of rapid prototyping studies comparing EID against conventional interface design principles. We focus primarily on the visual display, although some development of an ecological auditory display is also presented. The results of feedback from potential users as well as subject matter experts are discussed with respect to implications for future interface design in this field
Gut microbiota of Type 1 diabetes patients with good glycaemic control and high physical fitness is similar to people without diabetes: an observational study
Type 1 diabetes is the product of a complex interplay between genetic susceptibility and exposure to environmental factors. Existing bacterial profiling studies focus on people who are most at risk at the time of diagnosis; there are limited data on the gut microbiota of people with long-standing Type 1 diabetes. This study compared the gut microbiota of patients with Type 1 diabetes and good glycaemic control and high levels of physical-fitness with that of matched controls without diabetes.Ten males with Type 1 diabetes and ten matched controls without diabetes were recruited; groups were matched for gender, age, BMI, peak oxygen uptake (VO2max ), and exercise habits. Stool samples were analysed using next-generation sequencing of the 16S rRNA gene to obtain bacterial profiles from each individual. Phylogenetic investigation of communities by reconstruction of unobserved states (PICRUSt) was implemented to predict the functional content of the bacterial operational taxonomic units.Faecalibacterium sp., Roseburia sp. and Bacteroides sp. were typically the most abundant members of the community in both patients with Type 1 diabetes and controls, and were present in every sample in the cohort. Each bacterial profile was relatively individual and no significant difference was reported between the bacterial profiles or the Shannon diversity indices of Type 1 diabetes compared with controls. The functional profiles were more conserved and the Type 1 diabetes group were comparable with the control group.We show that both gut microbiota and resulting functional bacterial profiles from patients with long-standing Type 1 diabetes in good glycaemic control and high physical fitness levels are comparable with those of matched people without diabetes. This article is protected by copyright. All rights reserved
Black Hole Thermodynamics and Heavy Fermion Metals
Heavy fermion alloys at critical doping typically exhibit non-Fermi-liquid
behavior at low temperatures, including a logarithmic or power law rise in the
ratio of specific heat to temperature as the temperature is lowered. Anomalous
specific heat of this type is also observed in a simple class of gravitational
dual models that exhibit anisotropic scaling with dynamical critical exponent z
> 1.Comment: 17 pages, 4 figures; v2: added references; v3: matches published
versio
Gauss-Bonnet Black Holes and Heavy Fermion Metals
We consider charged black holes in Einstein-Gauss-Bonnet Gravity with
Lifshitz boundary conditions. We find that this class of models can reproduce
the anomalous specific heat of condensed matter systems exhibiting
non-Fermi-liquid behaviour at low temperatures. We find that the temperature
dependence of the Sommerfeld ratio is sensitive to the choice of Gauss-Bonnet
coupling parameter for a given value of the Lifshitz scaling parameter. We
propose that this class of models is dual to a class of models of
non-Fermi-liquid systems proposed by Castro-Neto et.al.Comment: 17 pages, 6 figures, pdfLatex; small corrections to figure 10 in this
versio
Detecting and monitoring incontinence associated dermatitis: Does impedance spectroscopy have a part to play?
This is the final version. Available from SAGE Publications via the DOI in this record. In this review, current understanding of the prevention and treatment of Incontinence Associated Dermatitis (IAD) is discussed. The need for preventative measures which target specific faecal/urinary irritants is highlighted, including the role of urease inhibitors. There is no existing internationally and clinically accepted method to diagnose and categorise the severity of IAD. Diagnosis currently relies on visual inspection; non-invasive techniques to assess skin barrier function could remove subjectiveness, particularly in darker skin tones. Impedance spectroscopy is a non-invasive technique which can be used to monitor skin barrier function, supporting visual assessments. Six studies (2003-2021) which used impedance to assess dermatitis were reviewed; inflamed skin was distinguishable from healthy skin in each case. This suggests that impedance spectroscopy could be useful in diagnosis early-stage IAD, potentially enabling earlier intervention. Finally, the authors present their initial findings on the role of urease in skin breakdown in an in vivo IAD model, using impedance spectroscopy.University of BathConvaTec Ltd.Annette TrustEngineering and Physical Sciences Research Council (EPSRC
Hand harvesting of seaweed: evidence review to support sustainable management
Natural Resources Wales commissioned this literature review to improve understanding of the range of potential impacts of hand gathering seaweed and to review potential management measures. The report will support managers to provide clear, evidence based and consistent advice to applications while protecting the seaweed resource.
The majority of hand harvesting activity is for food use, with limited amount taken for cosmetics and pharmaceuticals. Little evidence for collection of beach cast weed was
found in Wales and England, which is thought to be opportunistic and seasonal following winter storms, with applications as fertilizer or soil conditioner. A small amount of mature adult plants are also hand harvested to provide fertile material for seaweed cultivation.
Commercially in Wales and England, Sea spaghetti (Himanthalia elongata), dulse
(Palmaria palmata), Ulva spp., Porphyra spp., carrageen (Chondrus crispus), Fucus
serratus (some F. vesiculosus) and the kelps Laminaria digitata and Saccharina latissima
are the key species targeted.
Recreational harvesting activity targets a range of species, with some overlaps with
commercially harvested species. Of these, Laver, (Porphyra spp). is of particular
importance to recreational harvesters in South Wales, followed by F. vesiculosus, pepper
dulse (Osmundea spp), kelps, carrageen (C. crispus and Mastocarpus stellatus) and P.
palmata).
Growth rates, life history, seasonality and reproduction underpin recovery from harvesting.
These are species and site specific and may vary over time. Dispersal potential of
propagules is poorly understood, but is a key recovery mechanism and is thought to be low
for most species. For key targeted species, evidence for distribution and these life history
parameters is presented in the appendices as a series of species dossiers. The report
identifies how management should take these into consideration and highlights differences
between species. The wrack Ascophyllum nodosum is the most slow growing and long
lived of harvested species, followed by the kelp Laminaria hyperborea, other kelp and
wrack species, and perennial red seaweeds. Conversely Ulva spp. and Porphyra spp. are
fast growing and quick to mature and able to rapidly colonise newly cleared rock.
Seaweeds support the natural ecosystem and people through primary production/ carbon
fixation and nutrient cycling that underpins marine food webs. Seaweeds provide and
modify habitats for a wide range of organisms, including commercially targeted fish and
shellfish species. The contribution to ecosystem function and services varies with kelps
and brown seaweeds being of particular ecological importance.
The impact of harvesting varies according to species, scale, technique and local
environmental conditions. By removing seaweeds, harvesting reduces growth rates and
population dynamics, this reduces nutrient cycling and reduces habitat availability and
provision. While recovery may take place in some instances, changes in community
composition can occur as a result of competition and grazing pressure. These impacts
should be considered within harvesting management plans to mitigate adverse effects.
Invasive non-native species are a key risk for native species and habitats. A rapid
evidence assessment identified 33 invasive species of concern, likely to be associated with
harvested seaweeds, these include thirteen invasive seaweeds, thirteen attached or
19
fouling species and seven mobile species that may shelter amongst seaweeds. The risks
from these were prioritised based on impact on native species and habitats, relevance of
seaweed harvesting to dispersal and current distribution. Fourteen priority species were
identified, three of which may be of commercial interest. Measures to reduce risk of spread
include avoiding or reducing by-catch and ‘check clean dry’ equipment are suggested.
Existing harvesting guidance documents are centred around codes of conduct which are
not legally binding. Effective management will be site and species specific. Management
approaches may be voluntary (e.g. codes of conduct) or statutory (e.g. quotas), and can
be summarised as follows.
• Harvesting methods
- Cutting height, leave a proportion of the plant (holdfast and some frond)
remaining at the base;
- Selectively cut with scissors rather than plucking or uprooting to support
recovery and reduce by-catch;
- Avoid by-catch of epiphytes and vulnerable species
- Avoid harvesting reproductive material if possible (or only take half from each
plant in the case of H. elongata);
- For certain species (e.g. for F. serratus and F. vesiculosus), only harvest part
of mature plants
• Harvesting period
- Harvest during active growing season;
- Avoid harvesting during the reproductive season;
• Harvesting frequency
- Fallow periods for recovery of canopy in A. nodosum and perennial kelps
• Harvest limits
- Quotas, volumes or bag limits;
- Proportion of standing stock biomass removed/left remaining
• Harvesting spatial considerations
- Harvest sparsely, leaving unharvested plants between those taken;
- Shape, size and spacing of harvested areas (i.e. between harvested plants
or patches);
Knowledge of the available resource is essential for sustainable management of hand
harvesting of seaweeds. Simple methods of assessing and monitoring biomass were
discussed and some initial estimates of biomass of intertidal seaweed provided. Due to
gaps in evidence uncertainty remains regarding the lifecycle and recovery capacity of
certain species, particularly red seaweeds and the standing stock biomass of all species
available for harvest. This report has identified management approaches that are well supported and based on ecological considerations such as life-history and recovery
mechanisms. However, it is recognised that advice and action by managers for those
seaweeds where uncertainty exists regarding biomass and recoverability will need to be
precautionary.
Effective management will be site and species specific, utilising a combination of
management approaches. Seaweed harvesting activities provide an opportunity to involve
stakeholders to conduct applied research projects, monitoring sites before, during and
after harvesting and to trial effective management issues. Continued monitoring in some
form by harvesters could be a condition of any license to exploit wild stocks
Comparison of tumour-based (Petersen Index) and inflammation-based (Glasgow Prognostic Score) scoring systems in patients undergoing curative resection for colon cancer
After resection, it is important to identify colon cancer patients, who are at a high risk of recurrence and who may benefit from adjuvant treatment. The Petersen Index (PI), a prognostic model based on pathological criteria is validated in Dukes' B and C disease. Similarly, the modified Glasgow Prognostic Score (mGPS) based on biochemical criteria has also been validated. This study compares both the scores in patients undergoing curative resection of colon cancer. A total of 244 patients underwent elective resection between 1997 and 2005. The PI was constructed from pathological reports; the mGPS was measured pre-operatively. The median follow-up was 67 months (minimum 36 months) during which 109 patients died; 68 of them from cancer. On multivariate analysis of age, Dukes' stage, PI and mGPS, age (hazard ratio, HR, 1.74, P=0.001), Dukes' stage (HR, 3.63, P<0.001), PI (HR, 2.05, P=0.010) and mGPS (HR, 2.34, P<0.001) were associated independently with cancer-specific survival. Three-year cancer-specific survival rates for Dukes' B patients with the low-risk PI were 98, 92 and 82% for the mGPS of 0, 1 and 2, respectively (P<0.05). The high-risk PI population is small, in particular for Dukes' B disease (9%). The mGPS further stratifies those patients classified as low risk by the PI. Combining both the scoring systems could identify patients who have undergone curative surgery but are at high-risk of cancer-related death, therefore guiding management and trial stratification
Changes in body weight and food choice in those attempting smoking cessation: a cluster randomised controlled trial
<p><b>Background:</b> Fear of weight gain is a barrier to smoking cessation and significant cause of relapse for many people. The provision of nutritional advice as part of a smoking cessation programme may assist some in smoking cessation and perhaps limit weight gain. The aim of this study was to determine the effect of a structured programme of dietary advice on weight change and food choice, in adults attempting smoking cessation.</p>
<p><b>Methods:</b> Cluster randomised controlled design. Classes randomised to intervention commenced a 24-week intervention, focussed on improving food choice and minimising weight gain. Classes randomised to control received "usual care".</p>
<p><b>Results:</b> Twenty-seven classes in Greater Glasgow were randomised between January and August 2008. Analysis, including those who continued to smoke, showed that actual weight gain and percentage weight gain was similar in both groups. Examination of data for those successful at giving up smoking showed greater mean weight gain in intervention subjects (3.9 (SD 3.1) vs. 2.7 (SD 3.7) kg). Between group differences were not significant (p=0.23, 95% CI -0.9 to 3.5). In comparison to baseline improved consumption of fruit and vegetables and breakfast cereal were reported in the intervention group. A higher percentage of control participants continued smoking (74% vs. 66%).</p>
<p><b>Conclusions:</b> The intervention was not successful at minimising weight gain in comparison to control but was successful in facilitating some sustained improvements in the dietary habits of intervention participants. Improved quit rates in the intervention group suggest that continued contact with advisors may have reduced anxieties regarding weight gain and encouraged cessation despite weight gain. Research should continue in this area as evidence suggests that the negative effects of obesity could outweigh the health benefits achieved through reductions in smoking prevalence.</p>
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