2,488 research outputs found
Pair Production Constraints on Superluminal Neutrinos Revisited
We revisit the pair creation constraint on superluminal neutrinos considered
by Cohen and Glashow in order to clarify which types of superluminal models are
constrained. We show that a model in which the superluminal neutrino is
effectively light-like can evade the Cohen-Glashow constraint.Comment: 5 pages, typo fixed, footnote on sterile neutrinos added, refs. adde
Semyotique Project| Reflections on improvisation in the creative process of teaching and learning
Recommended from our members
Nitrogen cycling in Sabine Lake
As a part of continuing efforts to investigate nitrogen cycling in Texas estuaries, denitrification, nitrogen fixation, dissimilatory nitrate reduction to ammonium (DNRA), and sediment oxygen demand were measured in Sabine Lake, Texas. Estuarine phytoplankton production can be limited by N availability, and sediments often are an important source of dissolved inorganic N ... . Denitrification transforms combined N to gaseous forms ... . These end-products represent unavailable nutrient sources to most estuarine producers (e.g., phytoplankton and bacteria; Howarth et al. 1988). Thus, denitrification may drive systems toward N limitation (Seitzinger 1990). The purposes of this study were to evaluate the importance of denitrification in nitrogen cycling and examine environmental conditions influencing nitrogen cycling in Sabine Lake. A membrane inlet mass spectrometer (MIMS) for dissolved gas measurement and high performance liquid chromatography (HPLC) system for ammonium isotope measurements were used to quantify denitrification, N-fixation, DNRA, and sediment oxygen demand. Four sampling trips to Sabine Lake were made in June, September, December 2000 and March 2001. Here, we report water column measurements and incubation experiment results.Final report submitted to: The Texas Water Development Board, contract #2000-483-337July 2001Marine Scienc
Comment on “New Limits on Intrinsic Charm in the Nucleon from Global Analysis of Parton Distributions”
The complexities of 'otherness': reflections on embodiment of a young White British woman engaged in cross-generation research involving older people in Indonesia
This article has been made available through the Brunel Open Access Publishing Fund.If interviews are to be considered embodied experiences, than the potential influence of the embodied researcher must be explored. A focus on specific attributes such as age or ethnicity belies the complex and negotiated space that both researcher and participant inhabit simultaneously. Drawing on empirical research with stroke survivors in an ethnically mixed area of Indonesia, this paper highlights the importance of considering embodiment as a specific methodological concern. Three specific interactions are described and analysed, illustrating the active nature of the embodied researcher in narrative production and development. The intersectionality of embodied features is evident, alongside their fluctuating influence in time and place. These interactions draw attention to the need to consider the researcher within the interview process and the subsequent analysis and presentation of narrative findings. The paper concludes with a reinforcement of the importance of ongoing and meaningful reflexivity in research, a need to consider the researcher as the other participant, and specifically a call to engage with and present the dynamic nature of embodiment
Discrete Symmetries on the Light Front and a General Relation Connecting Nucleon Electric Dipole and Anomalous Magnetic Moments
We consider the electric dipole form factor, F_3(q^2), as well as the Dirac
and Pauli form factors, F_1(q^2) and F_2(q^2), of the nucleon in the
light-front formalism. We derive an exact formula for F_3(q^2) to complement
those known for F_1(q^2) and F_2(q^2). We derive the light-front representation
of the discrete symmetry transformations and show that time-reversal- and
parity-odd effects are captured by phases in the light-front wave functions. We
thus determine that the contributions to F_2(q^2) and F_3(q^2), Fock state by
Fock state, are related, independent of the fundamental mechanism through which
CP violation is generated. Our relation is not specific to the nucleon, but,
rather, is true of spin-1/2 systems in general, be they lepton or baryon. The
empirical values of the anomalous magnetic moments, in concert with empirical
bounds on the associated electric dipole moments, can better constrain theories
of CP violation. In particular, we find that the neutron and proton electric
dipole moments echo the isospin structure of the anomalous magnetic moments,
kappa^n ~ - kappa^p.Comment: 25 pages, 1 figure. Published version. Ref. adde
Youth, caregiver, and prescriber experiences of antipsychotic-related weight gain
Objectives. To explore the lived experience of youth, caregivers, and prescribers with antipsychotic medications. Design. We conducted a qualitative interpretive phenomenology study. Youth aged 11 to 25 with recent experience taking antipsychotics, the caregivers of youth taking antipsychotics, and the prescribers of antipsychotics were recruited. Subjects. Eighteen youth, 10 caregivers (parents), and 11 prescribers participated. Results. Eleven of 18 youth, six of ten parents, and all prescribers discussed antipsychotic-related weight gain. Participants were attuned to the numeric weight changes usually measured in pounds. Significant discussions occurred around weight changes in the context of body image, adherence and persistence, managing weight increases, and metabolic effects. These concepts were often inextricably linked but maintained the significance as separate issues. Participants discussed tradeoffs regarding the perceived benefits and risks of weight gain, often with uncertainty and inadequate information regarding the short- and long-term consequences. Conclusion. Antipsychotic-related weight gain in youth influences body image and weight management strategies and impacts treatment courses with respect to adherence and persistence. In our study, the experience of monitoring for weight and metabolic changes was primarily reactive in nature. Participants expressed ambiguity regarding the short- and long-term consequences of weight and metabolic changes
Two dimensionality in quasi one-dimensional cobalt oxides
By means of muon spin rotation and relaxation (SR) techniques, we have
investigated the magnetism of quasi one-dimensional (1D) cobalt oxides
CoO (=Ca, Sr and Ba, =1, 2, 3, 5 and
), in which the 1D CoO chain is surrounded by six equally spaced
chains forming a triangular lattice in the -plane, using polycrystalline
samples, from room temperature down to 1.8 K. For the compounds with =1 - 5,
transverse field SR experiments showed the existence of a magnetic
transition below 100 K. The onset temperature of the transition () was found to decrease with ; from 100 K for =1 to 60 K for
=5. A damped muon spin oscillation was observed only in the sample with
=1 (CaCoO), whereas only a fast relaxation obtained even at 1.8
K in the other three samples. In combination with the results of susceptibility
measurements, this indicates that a two-dimensional short-range
antiferromagnetic (AF) order appears below for all
compounds with =1 - 5; but quasi-static long-range AF order formed only in
CaCoO, below 25 K. For BaCoO (=), as decreased
from 300 K, 1D ferromagnetic (F) order appeared below 53 K, and a sharp 2D AF
transition occurred at 15 K.Comment: 12 pages, 14 figures, and 2 table
- …