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Buried (drift-filled) hollows in London â a review of their location and key characteristics
All data generated or analysed during this study are included in this published article (and its supplementary information files). For several features where the raw data are confidential contact the author, Amy
Flynn, to seek permission.© 2020 The Author(s). This paper compiles new and existing information relating to features frequently referred to as drift-filled hollows located within London. The key aim of this paper is to update the article written by Berry (1979, âLate Quaternary scour-hollows and related features in central Londonâ, QJEG, 12, 9â29, doi: 10.1144/GSL.QJEG.1979.012.01.03), producing a resource for both engineering projects and academic research. Fifty-four additional drift-filled hollows have been identified and their physical characteristics are tabulated where available information allows. A case study of the Nine Elms area is presented. The drift-filled hollows have been identified through examination and critical, quality assessment of historical borehole records, site investigation records, construction records and published articles. This enlarged dataset illustrates the high level of variability between features and, as a result, it is proposed that these features did not form due to a single process, but to differing processes.Engineering and Physical Sciences Research Council (EPSRC)
Formation of methane clathrate hydrates at elevated pressures and in the presence of nanoparticles
Natural gas hydrates occur widely on the ocean-bed and in permafrost regions, and have potential as an untapped energy resource. Their formation and growth, however, poses major problems for the energy sector due to their tendency to block oil and gas pipelines, whereas their melting is viewed as a potential contributor to climate change. Although recent advances have been made in understanding bulk methane hydrate formation, the effect of impurity particles, which are always present under conditions relevant to industry and the environment, remains an open question. Here we present results from neutron scattering experiments and molecular dynamics simulations that show that the formation of methane hydrate is insensitive to the addition of a wide range of impurity particles. Our analysis shows that this is due to the different chemical natures of methane and water, with methane generally excluded from the volume surrounding the nanoparticles. This has important consequences for our understanding of the mechanism of hydrate nucleation and the design of new inhibitor molecules
Crystal Structure of the Sodium Cobaltate Deuterate Superconductor NaxCoO2o4xD2O (x=1/3)
Neutron and x-ray powder diffraction have been used to investigate the
crystal structures of a sample of the newly-discovered superconducting sodium
cobaltate deuterate compound with composition Na0.31(3)CoO2o1.25(2)D2O and its
anhydrous parent compound Na0.61(1)CoO2. The deuterate superconducting compound
is formed by coordinating four D2O molecules (two above and two below) to each
Na ion in a way that gives Na-O distances nearly equal to those in the parent
compound. One deuteron of the D2O molecule is hydrogen bonded to an oxygen atom
in the CoO2 plane and the oxygen atom and the second deuteron of each D2O
molecule lie approximately in a plane between the Na layer and the CoO2 layers.
This coordination of Na by four D2O molecules leads to ordering of the Na ions
and D2O molecules. The sample studied here, which has Tc=4.5 K, has a refined
composition of Na0.31(3)CoO2o1.25(2)D2O, in agreement with the expected 1:4
ratio of Na to D2O. These results show that the optimal superconducting
composition should be viewed as a specific hydrated compound, not a solid
solution of Na and D2O (H2O) in NaxCoO2oyD2O. Studies of physical properties
vs. Na or D2O composition should be viewed with caution until it is verified
that the compound remains in the same phase over the composition range of the
study.Comment: 22 pages, 8 figure
Measuring narrative engagement: The heart tells the story
Stories play a fundamental role in human culture. They provide a mechanism for sharing cultural identity, imparting knowledge, revealing beliefs, reinforcing social bonds and providing entertainment that is central to all human societies. Here we investigated the extent to which the delivery medium of a story (audio or visual) affected conscious and sub-conscious engagement with the narrative. Although participants self-reported greater involvement for watching video relative to listening to auditory scenes, stronger physiological responses were recorded for auditory stories. Sensors placed at their wrists showed higher and more variable heart rates, greater electrodermal activity, and even higher body temperatures. We interpret these findings as physiological evidence that the stories were more cognitively and emotionally engaging when presented in an auditory format. This may be because listening to a story, rather than watching a video, is a more active process of co-creation, and that this imaginative process in the listener's mind is detectable on the skin at their wrist
Superconductivity in the Intercalated Graphite Compounds C6Yb and C6Ca
In this letter we report the discovery of superconductivity in the
isostructural graphite intercalation compounds C6Yb and C6Ca, with transition
temperatures of 6.5K and 11.5K respectively. A structural characterisation of
these compounds shows them to be hexagonal layered systems in the same class as
other graphite intercalates. If we assume that all the outer s-electrons are
transferred from the intercalant to the graphite sheets, then the charge
transfer in these compounds is comparable to other superconducting graphite
intercalants such as C8K 1,2 . However, the superconducting transition
temperatures of C6Yb and C6Ca are up to two orders of magnitude greater.
Interestingly, superconducting upper critical field studies and resistivity
measurements suggest that these compounds are significantly more isotropic than
pure graphite. This is unexpected as the effect of introducing the intercalant
is to move the graphite layer further apart.Comment: 2 Figures. Please see accompanying theoretical manuscript,
"Electronic Structure of the Superconducting Graphite Intercalates" by Csanyi
et al., cond-mat/050356
Non-hexagonal neural dynamics in vowel space
Are the grid cells discovered in rodents relevant to human cognition? Following up on two seminal studies by others, we aimed to check whether an approximate 6-fold, grid-like symmetry shows up in the cortical activity of humans who "navigate" between vowels, given that vowel space can be approximated with a continuous trapezoidal 2D manifold, spanned by the first and second formant frequencies. We created 30 vowel trajectories in the assumedly flat central portion of the trapezoid. Each of these trajectories had a duration of 240 milliseconds, with a steady start and end point on the perimeter of a "wheel". We hypothesized that if the neural representation of this "box" is similar to that of rodent grid units, there should be an at least partial hexagonal (6-fold) symmetry in the EEG response of participants who navigate it. We have not found any dominant n-fold symmetry, however, but instead, using PCAs, we find indications that the vowel representation may reflect phonetic features, as positioned on the vowel manifold. The suggestion, therefore, is that vowels are encoded in relation to their salient sensory-perceptual variables, and are not assigned to arbitrary gridlike abstract maps. Finally, we explored the relationship between the first PCA eigenvector and putative vowel attractors for native Italian speakers, who served as the subjects in our study
Randomised controlled trial of multi-modular motion-assisted memory desensitization and reconsolidation (3MDR) for male military veterans with treatment-resistant post-traumatic stress disorder
Objective To explore the potential efficacy of multiâmodular motionâassisted memory desensitisation and reprocessing (3MDR) in British military veterans with treatmentâresistant, serviceârelated PTSD. Methods Exploratory singleâblind, randomised, parallel arm, crossâover controlled trial with nested process evaluation to assess fidelity, adherence and factors that influence outcome. Results 42 participants (all male) were randomised with 83% retention at 12 weeks and 86% at 26 weeks. The difference in mean Clinician Administered PTSD Scale for DSMâ5 scores between the immediate and delayed 3MDR arms was â9.38 (95% CI â17.33 to â1.44, p = 0.021) at 12 weeks and â3.59 (â14.39 to 7.20, p= 0.513) at 26 weeks when both groups had received 3MDR. The likely effect size of 3MDR was found to be 0.65. Improvements were maintained at 26 week followâup. 3MDR was found to be acceptable to most, but not all, participants. Several factors that may impact efficacy and acceptability of 3MDR were identified. Conclusion 3MDR is a promising new intervention for treatmentâresistant PTSD with emerging evidence of effect
Large-Scale Pathway-Based Analysis of Bladder Cancer Genome-Wide Association Data from Five Studies of European Background
Pathway analysis of genome-wide association studies (GWAS) offer a unique opportunity to collectively evaluate genetic variants with effects that are too small to be detected individually. We applied a pathway analysis to a bladder cancer GWAS containing data from 3,532 cases and 5,120 controls of European background (nâ=â5 studies). Thirteen hundred and ninety-nine pathways were drawn from five publicly available resources (Biocarta, Kegg, NCI-PID, HumanCyc, and Reactome), and we constructed 22 additional candidate pathways previously hypothesized to be related to bladder cancer. In total, 1421 pathways, 5647 genes and âŒ90,000 SNPs were included in our study. Logistic regression model adjusting for age, sex, study, DNA source, and smoking status was used to assess the marginal trend effect of SNPs on bladder cancer risk. Two complementary pathway-based methods (gene-set enrichment analysis [GSEA], and adapted rank-truncated product [ARTP]) were used to assess the enrichment of association signals within each pathway. Eighteen pathways were detected by either GSEA or ARTP at Pâ€0.01. To minimize false positives, we used the I2 statistic to identify SNPs displaying heterogeneous effects across the five studies. After removing these SNPs, seven pathways (âAromatic amine metabolismâ [PGSEAâ=â0.0100, PARTPâ=â0.0020], âNAD biosynthesisâ [PGSEAâ=â0.0018, PARTPâ=â0.0086], âNAD salvageâ [PARTPâ=â0.0068], âClathrin derived vesicle buddingâ [PARTPâ=â0.0018], âLysosome vesicle biogenesisâ [PGSEAâ=â0.0023, PARTP<0.00012], âRetrograde neurotrophin signalingâ [PGSEAâ=â0.00840], and âMitotic metaphase/anaphase transitionâ [PGSEAâ=â0.0040]) remained. These pathways seem to belong to three fundamental cellular processes (metabolic detoxification, mitosis, and clathrin-mediated vesicles). Identification of the aromatic amine metabolism pathway provides support for the ability of this approach to identify pathways with established relevance to bladder carcinogenesis
Solid-State 31P and 1H NMR Investigations of Amorphous and Crystalline Calcium Phosphates Grown Biomimetically From a Mesoporous Bioactive Glass
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