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Early prehistoric petrology: A case study from Leicestershire.
This research focused on the petrographic analysis of prehistoric ceramics within the East Midlands. Prior assessments have been intermittent and not drawn together by a research-based agenda, with a few notable exceptions. This research uses petrographic analysis to shed light on early prehistoric society within Leicestershire, a county overlooked in comparison to other regions. The aim of this research was to investigate the procurement of raw materials and the subsequent production of Neolithic and early Bronze Age ceramics in Leicestershire, placing the county in its regional context. Petrographic slides from several early prehistoric sites were produced and analysed to determine the presence of any non-local material within the fabric of the ceramics. Existing petrographic data from other sites in the East Midlands were used as a comparative data set to test whether the ceramics from Leicestershire were typical or atypical of the wider production and procurement pattern. The results of the petrographic analysis on the Leicestershire sites indicated that the clay and inclusions were most likely of local origin, with no definitive evidence for non-local inclusions. However, the results from the comparative petrographic data obtained from sites within the wider East Midlands does support the movement of raw materials and/or finished ceramic products within the region. Preferential sources appear to have been continually exploited, both chronologically and geographically. The prime target of the exploitation was the Charnwood Forest area of Leicestershire, with groups from Derbyshire and Nottinghamshire utilising this resource in addition to more local groups within Leicestershire
Black Holes at the IceCube Neutrino Telescope
If the fundamental Planck scale is about a TeV and the cosmic neutrino flux
is at the Waxman-Bahcall level, quantum black holes are created daily in the
Antarctic ice-cap. We re-examine the prospects for observing such black holes
with the IceCube neutrino-detection experiment. To this end, we first revise
the black hole production rate by incorporating the effects of inelasticty,
i.e., the energy radiated in gravitational waves by the multipole moments of
the incoming shock waves. After that we study in detail the process of Hawking
evaporation accounting for the black hole's large momentum in the lab system.
We derive the energy spectrum of the Planckian cloud which is swept forward
with a large, O (10^6), Lorentz factor. (It is noteworthy that the boosted
thermal spectrum is also relevant for the study of near-extremal supersymmetric
black holes, which could be copiously produced at the LHC.) In the
semiclassical regime, we estimate the average energy of the boosted particles
to be less than 20% the energy of the neutrino-progenitor. Armed with such a
constraint, we determine the discovery reach of IceCube by tagging on "soft"
(relative to what one would expect from charged current standard model
processes) muons escaping the electromagnetic shower bubble produced by the
black hole's light descendants. The statistically significant 5-sigma excess
extends up to a quantum gravity scale ~ 1.3 TeV.Comment: Matching version to be published in Phys. Rev.
Regular Language Distance and Entropy
This paper addresses the problem of determining the distance between two regular languages. It will show how to expand Jaccard distance, which works on finite sets, to potentially-infinite regular languages.
The entropy of a regular language plays a large role in the extension. Much of the paper is spent investigating the entropy of a regular language. This includes addressing issues that have required previous authors to rely on the upper limit of Shannon\u27s traditional formulation of channel capacity, because its limit does not always exist. The paper also includes proposing a new limit based formulation for the entropy of a regular language and proves that formulation to both exist and be equivalent to Shannon\u27s original formulation (when it exists). Additionally, the proposed formulation is shown to equal an analogous but formally quite different notion of topological entropy from Symbolic Dynamics -- consequently also showing Shannon\u27s original formulation to be
equivalent to topological entropy.
Surprisingly, the natural Jaccard-like entropy distance is trivial in most cases. Instead, the entropy sum distance metric is suggested, and shown to be granular in certain situations
Control via electron count of the competition between magnetism and superconductivity in cobalt and nickel doped NaFeAs
Using a combination of neutron, muon and synchrotron techniques we show how
the magnetic state in NaFeAs can be tuned into superconductivity by replacing
Fe by either Co or Ni. Electron count is the dominant factor, since Ni-doping
has double the effect of Co-doping for the same doping level. We follow the
structural, magnetic and superconducting properties as a function of doping to
show how the superconducting state evolves, concluding that the addition of 0.1
electrons per Fe atom is sufficient to traverse the superconducting domain, and
that magnetic order coexists with superconductivity at doping levels less than
0.025 electrons per Fe atom.Comment: 4 pages, 6 figure
Nanopore direct RNA sequencing maps the complexity of Arabidopsis mRNA processing and m6A modification
Understanding genome organization and gene regulation requires insight into RNA transcription, processing and modification. We adapted nanopore direct RNA sequencing to examine RNA from a wild-type accession of the model plant Arabidopsis thaliana and a mutant defective in mRNA methylation (m6A). Here we show that m6A can be mapped in full-length mRNAs transcriptome-wide and reveal the combinatorial diversity of cap-associated transcription start sites, splicing events, poly(A) site choice and poly(A) tail length. Loss of m6A from 3’ untranslated regions is associated with decreased relative transcript abundance and defective RNA 30 end formation. A functional consequence of disrupted m6A is a lengthening of the circadian period. We conclude that nanopore direct RNA sequencing can reveal the complexity of mRNA processing and modification in full-length single molecule reads. These findings can refine Arabidopsis genome annotation. Further, applying this approach to less well-studied species could transform our understanding of what their genomes encode
Extinction in Lotka-Volterra model
Competitive birth-death processes often exhibit an oscillatory behavior. We
investigate a particular case where the oscillation cycles are marginally
stable on the mean-field level. An iconic example of such a system is the
Lotka-Volterra model of predator-prey competition. Fluctuation effects due to
discreteness of the populations destroy the mean-field stability and eventually
drive the system toward extinction of one or both species. We show that the
corresponding extinction time scales as a certain power-law of the population
sizes. This behavior should be contrasted with the extinction of models stable
in the mean-field approximation. In the latter case the extinction time scales
exponentially with size.Comment: 11 pages, 17 figure
Long-term survival from gastrocolic fistula secondary to adenocarcinoma of the transverse colon
BACKGROUND: Gastrocolic fistula is a rare presentation of both benign and malignant diseases of the gastrointestinal tract. Malignant gastrocolic fistula is most commonly associated with adenocarcinoma of the transverse colon in the Western World. Despite radical approaches to treatment, long-term survival is rarely documented. CASE PRESENTATION: We report a case of a 24-year-old woman who presented with the classic triad of symptoms associated with gastrocolic fistula. Radical en-bloc surgery and adjuvant chemotherapy were performed. She is still alive ten years after treatment. CONCLUSIONS: Gastrocolic fistula is an uncommon presentation of adenocarcinoma of the transverse colon. Radical en-bloc surgery with adjuvant chemotherapy may occasionally produce long-term survival
2passtools:two-pass alignment using machine-learning-filtered splice junctions increases the accuracy of intron detection in long-read RNA sequencing
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