53 research outputs found
OPERA data and The Equivalence Postulate of Quantum Mechanics
An interpretation of the recent results reported by the OPERA collaboration
is that neutrinos propagation in vacuum exceeds the speed of light. It has been
further been suggested that this interpretation can be attributed to the
variation of the particle speed arising from the Relativistic Quantum Hamilton
Jacobi Equation. I show that this is in general not the case. I derive an
expression for the quantum correction to the instantaneous relativistic
velocity in the framework of the relativistic quantum Hamilton-Jacobi equation,
which is derived from the equivalence postulate of quantum mechanics. While the
quantum correction does indicate deviations from the classical energy--momentum
relation, it does not necessarily lead to superluminal speeds. The quantum
correction found herein has a non-trivial dependence on the energy and mass of
the particle, as well as on distance travelled. I speculate on other possible
observational consequences of the equivalence postulate approach.Comment: 8 pages. Standard LaTex. References adde
Dynamic Changes in High-Sensitivity Cardiac Troponin I in Response to Anthracycline-Based Chemotherapy
Aims:
Treatment advances have improved cancer-related outcomes and shifted interest towards minimising long-term iatrogenic complications, particularly chemotherapy-related cardiotoxicity. High-sensitivity cardiac troponin I (hs-cTnI) assays accurately quantify very low concentrations of plasma troponin and enable early detection of cardiomyocyte injury prior to the development of myocardial dysfunction. The profile of hs-cTnI in response to anthracycline-based treatment has not previously been described.
Materials and methods:
This was a multicentre prospective observational cohort study. Female patients with newly diagnosed invasive breast cancer scheduled to receive anthracycline-based (epirubicin) chemotherapy were recruited. Blood sampling was carried out before and 24 h after each cycle. Hs-cTnI concentrations were measured using the Abbott ARCHITECTSTAT assay.
Results:
We recruited 78 women with a median (interquartile range) age of 52 (49–61) years. The median baseline troponin concentration was 1 (1–4) ng/l and the median cumulative epirubicin dose was 394 (300–405) mg/m2. Following an initial 33% fall 24 h after anthracycline dosing (P < 0.001), hs-cTnI concentrations increased by a median of 50% (P < 0.001) with each successive treatment cycle. In total, 45 patients had troponin measured immediately before the sixth treatment cycle, 21 (46.6%) of whom had hs-cTnI concentrations ≥16 ng/l, indicating myocardial injury. Plasma hs-cTnI concentrations before the second treatment cycle were a strong predictor of subsequent myocardial injury.
Conclusions:
Cardiotoxicity arising from anthracycline therapy is detectable in the earliest stages of breast cancer treatment and is cumulative with each treatment cycle. This injury is most reliably determined from blood sampling carried out before rather than after each treatment cycle
The effect of the endothelial glycocalyx layer on concentration polarisation of low density lipoprotein in arteries
Corrigendum: Delivery of crop pollination services is an insufficient argument for wild pollinator conservation
There is compelling evidence that more diverse ecosystems deliver greater benefits to people, and these ecosystem services have become a key argument for biodiversity conservation. However, it is unclear how much biodiversity is needed to deliver ecosystem services in a cost-effective way. Here we show that, while the contribution of wild bees to crop production is significant, service delivery is restricted to a limited subset of all known bee species. Across crops, years and biogeographical regions, crop-visiting wild bee communities are dominated by a small number of common species, and threatened species are rarely observed on crops. Dominant crop pollinators persist under agricultural expansion and many are easily enhanced by simple conservation measures, suggesting that cost-effective management strategies to promote crop pollination should target a different set of species than management strategies to promote threatened bees. Conserving the biological diversity of bees therefore requires more than just ecosystem-service-based arguments
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Measurement of the atmospheric muon charge ratio at TeV energies with MINOS
The 5.4 kton MINOS far detector has been taking charge-separated cosmic ray muon data since the beginning of August, 2003 at a depth of 2070 m.w.e. in the Soudan Underground Laboratory, Minnesota, USA. The data with both forward and reversed magnetic field running configurations were combined to minimize systematic errors in the determination of the underground muon charge ratio. When averaged, two independent analyses find the charge ratio underground to be N{sub {mu}}+/N{sub {mu}}-=1.374{+-}0.004(stat)-0.010{sup +0.012}(sys). Using the map of the Soudan rock overburden, the muon momenta as measured underground were projected to the corresponding values at the surface in the energy range 1-7 TeV. Within this range of energies at the surface, the MINOS data are consistent with the charge ratio being energy independent at the 2 standard deviation level. When the MINOS results are compared with measurements at lower energies, a clear rise in the charge ratio in the energy range 0.3-1.0 TeV is apparent. A qualitative model shows that the rise is consistent with an increasing contribution of kaon decays to the muon charge ratio
Test of Lorentz and CPT violation with Short Baseline Neutrino Oscillation Excesses
The sidereal time dependence of MiniBooNE electron neutrino and anti-electron
neutrino appearance data are analyzed to search for evidence of Lorentz and CPT
violation. An unbinned Kolmogorov-Smirnov test shows both the electron neutrino
and anti-electron neutrino appearance data are compatible with the null
sidereal variation hypothesis to more than 5%. Using an unbinned likelihood fit
with a Lorentz-violating oscillation model derived from the Standard Model
Extension (SME) to describe any excess events over background, we find that the
electron neutrino appearance data prefer a sidereal time-independent solution,
and the anti-electron neutrino appearance data slightly prefer a sidereal
time-dependent solution. Limits of order 10E-20 GeV are placed on combinations
of SME coefficients. These limits give the best limits on certain SME
coefficients for muon neutrino to electron neutrino and anti-muon neutrino to
anti-electron neutrino oscillations. The fit values and limits of combinations
of SME coefficients are provided.Comment: 14 pages, 3 figures, and 2 tables, submitted to Physics Letters
Creating the cultures of the future: cultural strategy, policy and institutions in Gramsci. Part one: Gramsci and cultural policy studies: some methodological reflections
Gramsci’s writings have rarely been discussed and used systematically by scholars in cultural policy studies, despite the fact that in cultural studies, from which the field emerged, Gramsci has been a major source of theoretical concepts. Cultural policy studies were, in fact, theorised as an anti-Gramscian project between the late 1980s and the early 1990s, when a group of scholars based in Australia advocated a major political and theoretical reorientation of cultural studies away from hegemony theory and radical politicisation, and towards reformist-technocratic engagement with the policy concerns of contemporary government and business. Their criticism of the ‘Gramscian tradition’ as inadequate for the study of cultural policy and institutions has remained largely unexamined in any detail for almost twenty years and seems to have had a significant role in the subsequent neglect of Gramsci’s contribution in this area of study. This essay, consisting of three parts, is an attempt to challenge such criticism and to provide an analysis of Gramsci’s writings, with the aim of proposing a more systematic contribution of his work to the theoretical development of cultural policy studies.
In Part One, I question the use of the notion of ‘Gramscian tradition’ made by its critics and challenge the claim that it was inadequate for the study of cultural policy and institutions.
In parts Two and Three, I consider Gramsci’s specific writings on questions of cultural strategy, policy and institutions, which have so far been overlooked by scholars, arguing that they provide further analytical insights to those offered by his more general concepts. More specifically, in Part Two, I consider Gramsci’s pre-prison writings and political practice in relation to questions of cultural strategy and institutions. I argue that the analysis of these early texts, which were written in the years in which Gramsci was active in party organisation and leadership, is fundamental not only for understanding the nature of Gramsci’s early and continued involvement with questions of cultural strategy and institutions, but also as a key for deciphering and interpreting cultural policy themes that he later developed in the prison notebooks, and which originated in earlier debates.
Finally, in Part Three, I carry out a detailed analysis of Gramsci’s prison notes on questions of cultural strategy, policy and institutions, which enrich the theoretical underpinnings for critical frameworks of analysis as well as for radical practices of cultural strategy, cultural policy-making and cultural organisation. I then answer the question of whether Gramsci’s insights amount to a theory of cultural policy
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Charge-separated atmospheric neutrino-induced muons in the MINOS far detector
We found 140 neutrino-induced muons in 854.24 live days in the MINOS far detector, which has an acceptance for neutrino-induced muons of 6.91 x 10{sup 6} cm{sup 2} sr. We looked for evidence of neutrino disappearance in this data set by computing the ratio of the number of low momentum muons to the sum of the number of high momentum and unknown momentum muons for both data and Monte Carlo expectation in the absence of neutrino oscillations. The ratio of data and Monte Carlo ratios, R, is R = 0.65{sub 0.12}{sup +0.15}(stat) {+-} 0.09(syst), a result that is consistent with an oscillation signal. A fit to the data for the oscillation parameters sin{sup 2} 2{theta}{sub 23} and {Delta}m{sub 23}{sup 2} excludes the null oscillation hypothesis at the 94% confidence level. We separated the muons into {mu}{sup -} and {mu}{sup +} in both the data and Monte Carlo events and found the ratio of the total number of {mu}{sup -} to {mu}{sup +} in both samples. The ratio of those ratios, {cflx R}{sub CPT}, is a test of CPT conservation. The result {cflx R}{sub CPT} = 0.72{sub -0.18}{sup +0.24}(stat){sub -0.04}{sup +0.08}(syst), is consistent with CPT conservation
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