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We propose the measurement of cavity-enhanced parity-nonconserving (PNC) optical rotation in several transitions of metastable Xe and Hg, including Xe (2P(3/2)(o))6s(2)[3/2](2)(o)â(2P(1/2)(o))6s(2)[1/2](1)(o) and Hg 6s6p (3)P(2)(o)â6s6p (1)P(1)(o), with calculated amplitude ratios of E(1)(PNC)/M1=11×10(-8) and 10×10(-8), respectively. We demonstrate the use of a high-finesse bow-tie cavity with counterpropagating beams and a longitudinal magnetic field, which allows the absolute measurement of chiral optical rotation, with a path length enhancement of about 10(4), necessary for PNC measurement from available column densities of 10(14) cm(-2) for metastable Xe or Hg. Rapid PNC-signal reversal, allowing robust background subtraction, is achieved by shifting the cavity resonance to an opposite polarization mode or by inverting the magnetic field. The precise measurement of isotope and nuclear-spin dependent E(1)(PNC) amplitudes provides a sensitive low-energy test of the standard model.
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Since 2000 the University of Basel offers the first Bachelor-Master's education in nursing science in Switzerland. The structure, content, faculty and students of this BSN-MSN curriculum are described. An evaluation study on the basis of quantitative and qualitative data drawn from students (n = 50) and alumni, respectively (n = 15), assesses strengths and weaknesses of this new education.
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Curriculum/normas , Educación en Enfermería/normas , Evaluación Educacional , Guías como Asunto , Evaluación de Programas y Proyectos de Salud , Ciencia/educación , Universidades/normas , SuizaRESUMEN
A 1 W tapered amplifier requiring only 200 µW of injection power at 780 nm is presented in this paper. This is achieved by injecting the seeding light into the amplifier from its tapered side and feeding the amplified light back into the small side. The amplified spontaneous emission of the tapered amplifier is suppressed by 75 dB. The double-passed tapered laser, presented here, is extremely stable and reliable. The output beam remains well coupled to the optical fiber for a timescale of months, whereas the injection of the seed light did not require realignment for over a year of daily operation.
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We investigate the nonlinear dynamics of two coupled annular Bose-Einstein condensates (BECs). For certain values of the coupling strength the nonrotating state with uniform density is unstable with respect to fluctuations in the higher angular momentum modes. The Bogoliubov spectrum possesses two branches, one of which exhibits distinct regions of instability enabling one to selectively occupy certain angular momentum modes. For sufficiently long evolution times, angular momentum Josephson oscillations spontaneously appear, breaking the initial chiral symmetry of the BECs.
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The development of a psychodynamic group comprising seven female nurses was studied for 1 year (31 sessions). The group was part of a 1-year postgraduate training in patient-centred nursing. The members of the group all worked on the same unit; none of them left the unit or the group during the study. As the nurse-patient relationship is considered to be crucial for patient-centred nursing, the group sessions focused on the problems which the nurses experienced in their relationships with the patients. The objective of the group-work was to improve the nurses' ability to reflect on these relationships. The purpose of the study was to evaluate the group sessions, concentrating on the characteristics of patients selected for discussions, group process over time, and impact of specific patient characteristics on the group-work. Transcriptions of the tape-recorded group sessions were made for systematic analysis. A category system was developed and validated to rate reflection about the patient, the nurses themselves and the nurse-patient relationship. The results showed that the nurses over-proportionally selected terminally ill patients, as well as patients who were female and within a similar age range as themselves. These results could be due to an identification with these patients, causing increased psychological stress on the nurses. Throughout the year, the nurses' verbal activity and their reflections about their patients increased, whereas their reflections about themselves decreased. The need to withdraw and protect oneself by focusing more on the patient than on oneself might have been a strategy the nurses used to cope with growing stress.
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Aprendizaje , Enfermeras y Enfermeros/psicología , Atención de Enfermería/psicología , Cuidado Terminal/psicología , Adulto , Femenino , Humanos , Masculino , Relaciones Enfermero-Paciente , Terapia Psicoanalítica , Factores de TiempoRESUMEN
We have tuned the whispering-gallery modes of a fused-silica microresonator over nearly 1 nm at 800 nm, i.e., over half a free spectral range, or 10(6) linewidths of the resonator. This result has been achieved by use of a new method based on the stretching of a two-stem microsphere. We describe devices that will permit new cavity QED experiments with this high- Q optical resonator when it is desirable to optimize its coupling to emitters with given transition frequencies. The demonstrated tuning capability is compatible with both UHV and low-temperature operation, which should be useful for future experiments with laser-cooled atoms or single quantum dots.
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We demonstrate an interference method to determine the low-energy elastic scattering amplitudes of a quantum gas. We linearly accelerate two ultracold atomic clouds up to energies of 1.2 mK and observe the collision halo by direct imaging in free space. From the interference between s- and d- partial waves in the differential scattering pattern we extract the corresponding phase shifts. The method does not require knowledge of the atomic density. This allows us to infer accurate values for the s- and d-wave scattering amplitudes from the zero-energy limit up to the first Ramsauer minimum using only the van der Waals C6 coefficient as theoretical input. For the 87Rb triplet potential, the method reproduces the scattering length with an accuracy of 6%.
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We report the formation of Bose-Einstein condensates into nonequilibrium states. Our condensates are much longer than equilibrium condensates with the same number of atoms, show strong phase fluctuations, and have a dynamical evolution similar to that of quadrupole shape oscillations of regular condensates. The condensates emerge in elongated traps as the result of local thermalization when the nucleation time is short compared to the axial oscillation time. We introduce condensate focusing as a new method to extract the phase-coherence length of Bose-Einstein condensates.