1,030 research outputs found
Optimizing gravitational-wave searches for a population of coalescing binaries: Intrinsic parameters
We revisit the problem of searching for gravitational waves from inspiralling
compact binaries in Gaussian coloured noise. For binaries with quasicircular
orbits and non-precessing component spins, considering dominant mode emission
only, if the intrinsic parameters of the binary are known then the optimal
statistic for a single detector is the well-known two-phase matched filter.
However, the matched filter signal-to-noise ratio is /not/ in general an
optimal statistic for an astrophysical population of signals, since their
distribution over the intrinsic parameters will almost certainly not mirror
that of noise events, which is determined by the (Fisher) information metric.
Instead, the optimal statistic for a given astrophysical distribution will be
the Bayes factor, which we approximate using the output of a standard template
matched filter search. We then quantify the possible improvement in number of
signals detected for various populations of non-spinning binaries: for a
distribution of signals uniformly distributed in volume and with component
masses distributed uniformly over the range ,
at fixed expected SNR, we find more
signals at a false alarm threshold of Hz in a single detector. The
method may easily be generalized to binaries with non-precessing spins.Comment: Version accepted by Phys. Rev.
The calculation of convective and condensation heat transfer coefficient to surfaces held in an acoustic field or subjected to mechanical oscillations
The work described in this thesis falls into five parts. Four
of these parts deal with the extension of the Danckwerts–Mickley
surface renewal concept for turbulent mixing, to the problem of
calculating the convective and condensation· heat transfer coefficients
from surfaces which are in mechanical oscillation, or are maintained
in an acoustic field. The fifth part discusses experiments carried
out by the author on the condensation of steam at atmospheric pressure
on a horizontal tube subjected to mechanical oscillations in the
vertical plane. A perturbation analysis of the problem has also been
carried out and compared with experiment. [Continues.
The blind leading the blind: Mutual refinement of approximate theories
The mutual refinement theory, a method for refining world models in a reactive system, is described. The method detects failures, explains their causes, and repairs the approximate models which cause the failures. The approach focuses on using one approximate model to refine another
The ASPIRE-to-Excellence Initiative:Can We recognize Excellence in Student Engagement with the Curriculum?
Highest weight vectors for classical reductive groups
A result by Tange from 2015 gave bases for the spaces of highest weight vectors for the action of GL_r×GL_s on k[Mat_{rs}^m] over a field of characteristic zero, and in arbitrary characteristic for certain weights; here, we generalise this to give bases for the spaces of highest weight vectors in k[Mat_{rs}^m] of any given weight in arbitrary characteristic. The motivation for this is to apply the technique of transmutation to describe the highest weight vectors for the conjugation action of GL_n on k[Mat_n]. Then, we use similar methods but in characteristic zero to describe finite spanning sets for the spaces of highest weight vectors for a certain polynomial action of GL_r on k[Mat_r^l] (derived from the GL_r-action on Mat_r given by g·A=gAg^T), and apply this to the conjugation action of the symplectic group Sp_n on k[sp_n]
Higher Education outreach to widen participation: toolkits for practitioners. Overview
The toolkits are a distillation of the learning, methods and resources developed by Aimhigher and the Lifelong Learning Network programmes to support the effective strategy, management and delivery of outreach work to encourage progression to higher education for under-represented groups. The toolkits recontextualise the learning from these programmes to fit the current higher education environment. The toolkits form a suite of four (see links to right). They include: • Toolkit 1 Partnership • Toolkit 2 Targeting • Toolkit 3 Programmes • Toolkit 4 Evaluation • Resources and glossary.This is the second and updated edition, the first edition of the Toolkits was published in December 2012.Higher Education Funding Council for England (HEFCE
The Examination Effect: A Comparison of the Outcome of Patent Examination in the US, Europe and Australia, 16 J. Marshall Rev. Intell. Prop. L. 21 (2016)
The article provides an answer to a question that, rather surprisingly, has not been addressed in the academic literature to date: What is the practical effect of patent examination? It does so by undertaking an empirical analysis of the examination of nearly 500 patent applications, filed in identical form, in three patent offices: the United States Patent and Trademark Office (USPTO), the European Patent Office (EPO), and the Australian Patent Office (APO). By comparing the form of claim 1 as granted with claim 1 in the patent application, we can identify whether there is any meaningful difference between the two and, if so, what is the type of difference. Any identifiable difference will show both the extent to which, and the way in which, the examination process within each office has a practical effect. Furthermore, by comparing the frequency with which each office effects meaningful change to claim 1, we can identify in which of the offices the process of examination has the greatest practical effect. We find that the routine effect of patent examination is to produce meaningful change, specifically a narrowing, to the definition of the invention contained in claim 1 of the patent. Importantly, this effect occurs more often in the USPTO than in the EPO, and more often in both of those offices than in the APO. Notably, our findings suggest that the quality of patents granted by the USPTO is higher than those granted by the other two offices despite its reputation for issuing many bad quality patents
To Follow Up or Not? A new model of supportive care for early breast cancer: Interim Results
To Follow Up or Not? A New Model of Supportive Care for Early Breast Cancer Background: Routine follow-up after curative treatment for early breast cancer exists to monitor for local recurrence and provide support for patients. Hospital visits can be stressful for patients and evidence indicates most recurrences are first identified by the patient. The value of resource-intense clinical follow-up is constantly being questioned. Many believe that time spent seeing essentially well-women is not clinically beneficial or an efficient use of time. Methods: This pilot study tested the feasibility and acceptability of a new supportive model of follow-up using quality-of-life (QOL) questionnaires plus qualitative diary evaluations. All patients attended four half day patient education workshops with course evaluations, followed by randomised to open access (OA) or hospital follow up (HFU). QOL including Hospital Anxiety and Depression Score (HADS), EORTC QLQ-C30 and BR23 were performed at baseline and 6 months, with further results awaited for 12, 18 and 24 months. Results: 106 women were recruited to the pilot study. 53 were randomised to HFU and 53 to OA. Multivariate analyses of covariance (MANCOVA) tests were conducted on all QOL data. Age was included as a covariate. Follow-up ANCOVAs on individual function and symptom outcomes were also conducted. The MANCOVA analyses indicated no statistically significant differences in change scores between HFU and OA groups, or between patients of different ages, on any of the three questionnaires. In all cases the effect of group had a greater effect on change (baseline-6 months) scores than the effect of age. Univariate ANCOVA tests and descriptive analyses showed performance improvement in many of the individual function and symptom scales in the OA group. Conclusions: While open access patients showed greater mean improvements in more scales than patients seen in clinic, follow-up method does not appear to significantly affect overall outcomes on any of the three questionnaires. As an influencing factor, the patients' age is less significant than the assigned group. This new model is feasible and acceptable. It is being adopted as standard across the Yorkshire Cancer Network
Evaluation of a novel assay for detection of the fetal marker RASSF1A: facilitating improved diagnostic reliability of noninvasive prenatal diagnosis
BackgroundAnalysis of cell free fetal (cff) DNA in maternal plasma is used routinely for non invasive prenatal diagnosis (NIPD) of fetal sex determination, fetal rhesus D status and some single gene disorders. True positive results rely on detection of the fetal target being analysed. No amplification of the target may be interpreted either as a true negative result or a false negative result due to the absence or very low levels of cffDNA. The hypermethylated RASSF1A promoter has been reported as a universal fetal marker to confirm the presence of cffDNA. Using methylation-sensitive restriction enzymes hypomethylated maternal sequences are digested leaving hypermethylated fetal sequences detectable. Complete digestion of maternal sequences is required to eliminate false positive results.MethodscfDNA was extracted from maternal plasma (n = 90) and digested with methylation-sensitive and insensitive restriction enzymes. Analysis of RASSF1A, SRY and DYS14 was performed by real-time PCR.ResultsHypermethylated RASSF1A was amplified for 79 samples (88%) indicating the presence of cffDNA. SRY real time PCR results and fetal sex at delivery were 100% accurate. Eleven samples (12%) had no detectable hypermethylated RASSF1A and 10 of these (91%) had gestational ages less than 7 weeks 2 days. Six of these samples were male at delivery, five had inconclusive results for SRY analysis and one sample had no amplifiable SRY.ConclusionUse of this assay for the detection of hypermethylated RASSF1A as a universal fetal marker has the potential to improve the diagnostic reliability of NIPD for fetal sex determination and single gene disorders
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