4,005 research outputs found
Transverse Galaxy Velocities from Multiple Topological Images
The study of the kinematics of galaxies within clusters or groups has the
limitation that only one of the three velocity components and only two of the
three spatial components of a galaxy position in six-dimensional phase space
can normally be measured. However, if multiple topological images of a cluster
exist, then the radial positions and sky plane mean velocities of galaxies in
the cluster may also be measurable from photometry of the two cluster images.
The vector arithmetic and principles of the analysis are presented. These are
demonstrated by assuming the suggested topological identification of the
clusters RX J1347.5-1145 and CL 09104+4109 to be correct and deducing the
sky-plane relative velocity component along the axis common to both images of
this would-be single cluster.
Three out of four of the inferred transverse velocities are consistent with
those expected in a rich cluster. A control sample of random `common' sky-plane
axes, independent of the topological hypothesis, implies that this is not
surprising. This shows that while galaxy kinematics are deducible from
knowledge of cosmological topology, it is not easy to use them to refute a
specific candidate manifold.Comment: 13 pages, 7 figures, accepted for MNRA
Celestial Landscapes and Heavenly Ascents: The Slavonic Book of the Holy Secrets of Enoch the Just (2 Enoch)
Astronomical Knowledge in the Slavonic Apocalypse of Enoch: Traces of Ancient Scientific Models
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Examining Bullying, Harassment, and Horizontal Violence (BHHV) in Student Nurses
Bullying, harassment, and horizontal violence (BHHV) is commonly reported by student nurses during their clinical education. Despite decades of mention in the literature, no instrument is available to specifically measure the student nurse’s experience of BHHV during clinical education. Purpose: The purpose of this dissertation is to examine the experience of BHHV in a population of student nurses matriculating during their clinical education in New York. The experience of BHHV is measured with the BEHAVE Survey, the instrument developed and tested for this purpose. Methods: This dissertation is presented in three-manuscripts: (1) a comprehensive review of the literature using The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) Statement as the methodological guide, (2) the initial psychometric testing of BEHAVE (Bulling, harassment, and HorizontAl ViolencE) for validity and reliability at a university-based school of nursing in New York, and (3) a descriptive, quantitative survey of baccalaureate nursing students at a university-based school of nursing in New York completed as a field test of the BEHAVE. Results: Despite variations in methodology, measurement, terms, definitions, and coding of behaviors and sources of BHHV, the findings of this literature review indicate that student nurses are common targets of BHHV during clinical education, regardless of demographic characteristics, disability, sexual orientation, geography location, academic institution or program type. Psychometric testing indicated: scale-level content validity index among experts 0.89, r = 0.97, a Cronbach’s α 0.94, and percent agreement 93% in test-retest reliability. BEHAVE was administered to a total of 32 participants (96.7% participation rate). Approximately 72% reporting current experienced or observed BHHV with 46.8% (36/77) of incidents originated from a nurse. Conclusions: The evidence from both the literature and this field trial suggests that BHHV is a common experience among nursing students. This is significant because student nurses are vulnerable to BHHV and studies including students have been limited to date. Therefore, it behooves the research community to continue to explore the impact of BHHV on the student nurse’s socialization into the professional nursing role. Further knowledge may inform targeted interventions to reduce BHHV and improve the ability of nursing students to minimize the impact of BHHV should it occur
Optimal control of a leaking qubit
Physical implementations of quantum bits can contain coherent transitions to
energetically close non-qubit states. In particular, for anharmonic oscillator
systems such as the superconducting phase qubit and the transmon a two-level
approximation is insufficient. We apply optimal control theory to the envelope
of a resonant Rabi pulse in a qubit in the presence of a single, weakly
off-resonant leakage level. The gate error of a spin flip operation reduces by
orders of magnitude compared to simple pulse shapes. Near-perfect gates can be
achieved for any pulse duration longer than an intrinsic limit given by the
nonlinearity. The pulses can be understood as composite sequences that refocus
the leakage transition. We also discuss ways to improve the pulse shapes.Comment: 4 pages, 2 figure
Why do planetary wave number one and the ozone transport vary annually in the Northern Hemisphere and semiannually in the Southern Hemisphere
Evidence is cited from these studies and those of others showing the different nature of the yearly variations of the middle atmospheres of the Northern and Southern Hemispheres. The Northern Hemisphere middle atmosphere is shown to be characterized by annual variations in planetary wave number one amplitude and the accompanying ozone transports. The Southern Hemisphere middle atmosphere is shown to be characterized by semiannual variations in the amplitude of planetary wave number one and the accompanying ozone transports. The amplitude of wave number two in both hemispheres appears to vary annually. Examination is made of the nature of the planetary wave forcing in both hemispheres as well as the planetary wave propagation characteristics in both hemispheres in an attempt to better understand this
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