671 research outputs found
Positron emission tomography PET/CT harmonisation study of different clinical PET/CT scanners using commercially available software
Objectives: Harmonisation is the process whereby
standardised uptake values from different scanners can
be made comparable. This PET/CT pilot study aimed to
evaluate the effectiveness of harmonisation of a modern
scanner with image reconstruction incorporating resolution recovery (RR) with another vendor older scanner operated in two-dimensional (2D) mode, and for both against a European standard (EARL). The vendor-proprietary software EQ•PET was used, which achieves harmonisation with a Gaussian smoothing. A substudy investigated effect of RR on harmonisation.
Methods: Phantom studies on each scanner were
performed to optimise the smoothing parameters
required to achieve successful harmonisation. 80
patients were retrospectively selected; half were imaged
on each scanner. As proof of principle, a cohort of 10
patients was selected from the modern scanner subjects
to study the effects of RR on harmonisation.
Results: Before harmonisation, the modern scanner
without RR adhered to EARL specification. Using the
phantom data, filters were derived for optimal harmonisation between scanners and with and without RR as
applicable, to the EARL standard. The 80-patient
cohort did not reveal any statistically significant differences. In the 10-patient cohort SUVmax for RR > no RR irrespective of harmonisation but differences lacked statistical significance (one-way ANOVA F(3.36) = 0.37, p = 0.78). Bland-Altman analysis showed that harmonisation reduced the SUVmax ratio between RR and no RR to 1.07 (95% CI 0.96–1.18) with no outliers.
Conclusions: EQ•PET successfully enabled harmonisation
between modern and older scanners and against
the EARL standard. Harmonisation reduces SUVmax and
dependence on the use of RR in the modern scanner.
Advances in knowledge: EQ•PET is feasible to harmonise
different PET/CT scanners and reduces the effect of
RR on SUVmax
The Indian family on UK reality television: Convivial culture in salient contexts
This is the author's accepted manuscript. The final published article is available from the link below, copyright 2012 @ the author.This article demonstrates how The Family (2009), a fly-on-the wall UK reality series about a British Indian family, facilitates both current public service broadcasting requirements and mass audience appeal. From a critical cultural studies perspective, the author examines the journalistic and viewer responses to the series where authenticity, universality, and comedy emerge as major themes. Textual analysis of the racialized screen representations also helps locate the series within the contexts of contested multiculturalism, genre developments in reality television and public service broadcasting. Paul Gilroy’s concept of convivial culture is used as a frame in understanding how meanings of the series are produced within a South Asian popular representational space. The author suggests that the social comedy taxonomy is a prerequisite for the making of this particular observational documentary. Further, the popular (comedic) mode of conviviality on which the series depends is both expedient and necessary within the various sociopolitical contexts outlined
Treatment of classical Hodgkin lymphoma in young adults aged 18-30 years with a modified paediatric Hodgkin lymphoma protocol. Results of a multicentre phase II clinical trial (CRUK/08/012)
This phase II trial was designed to determine the safety and efficacy of a modified paediatric risk-stratified protocol in young adults (18-30 years) with classical Hodgkin Lymphoma. The primary end-point was neurotoxicity rate. The incidence of grade 3 neurotoxicity was 11% (80% CI, 5-19%); a true rate of neuropathy of >15% cannot be excluded. Neuropathy and associated deterioration in quality of life was largely reversible. The overall response rate was 100% with 40% complete remission (CR) rate. Twelve months disease-free survival (DFS) was 91%. We demonstrate that a risk-stratified paediatric combined modality treatment approach can be delivered to young adults without significant irreversible neuropathy
Failure of JoAnne's Global Fit to the Wilson Coefficients in Rare B Decays: A Left-Right Model Example
In the Standard Model and many of its extensions, it is well known that all
of the observables associated with the rare decays and can be expressed in terms of the three Wilson coefficients,
, together with several universal kinematic
functions. In particular it has been shown that the numerical values of these
coefficients can be uniquely extracted by a three parameter global fit to data
obtainable at future -factories given sufficient integrated luminosity. In
this paper we examine if such global fits are also sensitive to new operators
beyond those which correspond to the above coefficients, i.e., whether is it
possible that new operators can be of sufficient importance for the three
parameter fit to fail and for this to be experimentally observable. Using the
Left-Right Symmetric Model as an example of a scenario with an extended
operator basis, we demonstrate via Monte Carlo techniques that such a
possibility can indeed be realized. In some sense this potential failure of the
global fit approach can actually be one of its greatest successes in
identifying the existence of new physics.Comment: 30 pages, 6 figure
Heavy Quark Symmetry Violation in Semileptonic Decays of D Mesons
The decays of mesons to and final states exhibit
significant deviations from the predictions of heavy-quark symmetry, as one
might expect since the strange quark's mass is of the same order as the QCD
scale. Nonetheless, in order to understand where the most significant effects
might lie for heavier systems (such as and ),
the pattern of these deviations is analyzed from the standpoint of perturbative
QCD and corrections. Two main effects are noted. First, the
perturbative QCD corrections lead to an overall decrease of predicted rates,
which can be understood in terms of production of excited kaonic states.
Second, effects tend to cancel the perturbative QCD
corrections in the case of decay, while they have minimal effect in
decay.Comment: 25 pages (LaTeX) + 7 pages of Postscript figures (included at end),
EFI-92-3
A Replication Study of GWAS-Derived Lipid Genes in Asian Indians: The Chromosomal Region 11q23.3 Harbors Loci Contributing to Triglycerides
Recent genome-wide association scans (GWAS) and meta-analysis studies on European populations have identified many genes previously implicated in lipid regulation. Validation of these loci on different global populations is important in determining their clinical relevance, particularly for development of novel drug targets for treating and preventing diabetic dyslipidemia and coronary artery disease (CAD). In an attempt to replicate GWAS findings on a non-European sample, we examined the role of six of these loci (CELSR2-PSRC1-SORT1 rs599839; CDKN2A-2B rs1333049; BUD13-ZNF259 rs964184; ZNF259 rs12286037; CETP rs3764261; APOE-C1-C4-C2 rs4420638) in our Asian Indian cohort from the Sikh Diabetes Study (SDS) comprising 3,781 individuals (2,902 from Punjab and 879 from the US). Two of the six SNPs examined showed convincing replication in these populations of Asian Indian origin. Our study confirmed a strong association of CETP rs3764261 with high-density lipoprotein cholesterol (HDL-C) (p = 2.03×10−26). Our results also showed significant associations of two GWAS SNPs (rs964184 and rs12286037) from BUD13-ZNF259 near the APOA5-A4-C3-A1 genes with triglyceride (TG) levels in this Asian Indian cohort (rs964184: p = 1.74×10−17; rs12286037: p = 1.58×10−2). We further explored 45 SNPs in a ∼195 kb region within the chromosomal region 11q23.3 (encompassing the BUD13-ZNF259, APOA5-A4-C3-A1, and SIK3 genes) in 8,530 Asian Indians from the London Life Sciences Population (LOLIPOP) (UK) and SDS cohorts. Five more SNPs revealed significant associations with TG in both cohorts individually as well as in a joint meta-analysis. However, the strongest signal for TG remained with BUD13-ZNF259 (rs964184: p = 1.06×10−39). Future targeted deep sequencing and functional studies should enhance our understanding of the clinical relevance of these genes in dyslipidemia and hypertriglyceridemia (HTG) and, consequently, diabetes and CAD
P and CP violation in B physics
While the Kobayashi--Maskawa single phase origin of CP violation passed its
first crucial precision test in , the chirality of weak
-quark couplings has not yet been carefully tested. We discuss recent
proposals for studying the chiral and CP-violating structure of these couplings
in radiative and in hadronic B decays.Comment: 15 pages, talk at PASCOS'03, Tata Inst., Mumbai, Jan. 200
Keeping the faith: reflections on religious nurture among young British Sikhs
Although young Sikhs are regularly accused of not attending gurdwara and not being interested in Sikhism, many young Sikhs are now learning about Sikhism outside traditional religious institutions. Using data gathered as part of a research project studying the transmission of Sikhism among 18- to 30-year-old British Sikhs, this essay explores how young Sikhs are learning about Sikhism in their pre-adult life stage. Examining the influences of the family and the school environment and the various methods used in gurdwaras, this essay offers a retrospective look on the ways in which young Sikhs are nurtured and socialised into Sikhism, providing an understanding from the perspective of young Sikhs themselves about which methods actually work and why
VLBI Observations of a Complete Sample of Radio Galaxies. 10 Years Later
A complete sample of 27 radio galaxies was selected from the B2 and 3CR
catalogs, in order to study their properties on the milliarcsecond scale. In
the Appendix of this paper we present new radio images for 12 of them. Thanks
to the present data, all the sources in this sample have been imaged at mas
resolution. We discuss the general results. In particular we stress the
evidence for high velocity jets in low power radio galaxies, we compare high
and low power sources, and discuss the source properties in the light of the
unified scheme models. We derive that the properties of parsec scale jets are
similar in sources with different total radio power and kpc scale morphology.
From the core - total radio power correlation, we estimate that relativistic
jets with Lorentz factor in the range 3 - 10 are present in high and
low power radio sources. We discuss also the possible existence of a two
velocity structure in the jets (fast spine and lower velocity external shear
layer).Comment: 38 pages, 18 figures with an Appendix; ApJ in press (vol. 551, Apr.
20, 2001 issue
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