5,244 research outputs found
Training course for radiation safety technicians
Course of instruction includes sections on basic information, natural radioactivity, properties of alpha, beta, gamma, X rays, and neutrons, concepts of radiation units and dose determinations, shielding, biological effects, background radiation, radiation protection standards, and internal dose calculation
Loss Dependence on Geometry and Applied Power in Superconducting Coplanar Resonators
The loss in superconducting microwave resonators at low-photon number and low
temperatures is not well understood but has implications for achievable
coherence times in superconducting qubits. We have fabricated single-layer
resonators with a high quality factor by patterning a superconducting aluminum
film on a sapphire substrate. Four resonator geometries were studied with
resonant frequencies ranging from 5 to 7 GHz: a quasi-lumped element resonator,
a coplanar strip waveguide resonator, and two hybrid designs that contain both
a coplanar strip and a quasi-lumped element. Transmitted power measurements
were taken at 30 mK as a function of frequency and probe power. We find that
the resonator loss, expressed as the inverse of the internal quality factor,
decreases slowly over four decades of photon number in a manner not merely
explained by loss from a conventional uniform spatial distribution of two-level
systems in an oxide layer on the superconducting surfaces of the resonator.Comment: 4 pages, 5 figures, Submitted to ASC 2010 conference proceeding
Relationship of Ethical Knowledge to Action in Senior Baccalaureate Nursing Students
Nursing educators are expected to prepare students to practice in a complex health care environment yet nursing curriculums vary in how the ethical reasoning ability of students is developed. To effectively manage clinical situations that have ethical implications, practitioners need to be able to recognizing these situations and have the ability to take action. Using an established instrument known as Ketefian’s Judgments About Nursing Decisions (JAND) to survey nursing students, this study examined the relationship between knowledge of the Code of Ethics for Nurses to choices of action in senior nursing students in baccalaureate nursing programs enrolled in the last semester of classes before graduating. The research process also included exploration of individual characteristics of the students to determine what impact, if any, these had on the relationship between knowledge and choice of action. There was a positive, significant, correlation between knowledge and action in senior baccalaureate nursing students. There was no significant difference in this relationship as a result of education or experience within the student group but a large discrepancy in the numbers of participants in each group may have impacted this finding. Thus college credit in courses on ethics, previous experience with making health care decisions, and general experience in health care did not significantly impact this relationship, but did indicate a need for further research
Habitat Preferences and Food Habits of Striped Skunks in Eastern South Dakota
Habitat preferences of striped skunks (Mephitis mephitis) in Brookings County, South Dakota, were determined rom the relationship of nighttime roadside indices to 25 habitat variables of 277, 1-square mile plots. Winter tracking was also conducted. Skunks were collected on the study area in 1972-1972, and contents of 59 stomachs and 63 colons were studied to determine food habits. Indices of prey abundance in different habitat types were obtained from snap-trap surveys. The 25 variables accounted for 14.9 percent of the variation in skunk numbers. The relationships of three of these variables to skunk numbers were significant (P\u3c0.05). The significant variables and the variation accounted for by each were: (a) number of areas of idle grassland, 6.3 percent; (b) number of rockplies, 1.5 percent; and (c) acreage of idle grassland, 1.3 percent. Idle grasslands were the main activity centers of skunks tracked during the winter. Food habits were analyzed for the periods March-April, May-June, July-August, and September-November. Insects were the most frequently found food item in al time periods except March-April, during which mammals occurred more frequently. Mammals made up the largest volume of food in March-April and May-June. Amphibians made up the greatest volume in July-August, while amphibians, mammals, and insects were found in nearly equal volumes in September-November. Bird remains occurred during all time periods. Eggs were found in May-June and July-August. Meadow voles (Microtus spp.), the most frequent mammalian food item during all time periods, were common only in habitat types having heavy residual cover. Idle grassland is an important nestling cover for gamebirds and waterfowl. Since the number of areas of this cover type apparently has a stronger relationship with skunk numbers than its total acreage, grassland nesting cover might best be managed in large, homogeneous blocks. Areas managed in this way would probably support lower skunk densities than more diverse areas containing equal acreages of idle grassland, thus reducing nest predation by skunks. Skunk control programs should be most efficient when centered around idle grassland and rockplies
Group-blind detection with very large antenna arrays in the presence of pilot contamination
Massive MIMO is, in general, severely affected by pilot contamination. As
opposed to traditional detectors, we propose a group-blind detector that takes
into account the presence of pilot contamination. While sticking to the
traditional structure of the training phase, where orthogonal pilot sequences
are reused, we use the excess antennas at each base station to partially remove
interference during the uplink data transmission phase. We analytically derive
the asymptotic SINR achievable with group-blind detection, and confirm our
findings by simulations. We show, in particular, that in an
interference-limited scenario with one dominant interfering cell, the SINR can
be doubled compared to non-group-blind detection.Comment: 5 pages, 4 figure
Responsiveness of the International Classification of Functioning, Disability and Health (ICF) Core Set for rheumatoid arthritis
Background: The comprehensive International
Classification of Functioning, Disability and Health (ICF)
Core Set for rheumatoid arthritis (RA) is a selection of 96
categories from the ICF, representing relevant aspects in
the functioning of patients with RA.
Objectives: To study the responsiveness of the ICF Core
Set for RA in rheumatological practice.
Methods: A total of 46 patients with RA (72% women,
mean (SD) age 53.6 (12.6) years, disease duration 6.3
(8.0) years) were interviewed at baseline and again after
6 months treatment with a disease-modifying antirheumatic
drug (DMARD), applying the ICF Core Set for RA
with qualifiers for problems on a modified three-point
scale (no problem, mild/moderate, severe/complete).
Patient-reported outcomes included Modified Health
Assessment Questionnaire (MHAQ) and Short-Form 36
(SF-36) health survey, and disease activity was calculated.
Responsiveness was measured as change in
qualifiers in ICF categories, and was also compared with
change in patient-reported outcomes.
Results: After 6 months of DMARD treatment,
improvement by at least one qualifier was seen in 20% of
patients (averaged across all ICF categories), 71%
experienced no change and 9% experienced worsening
symptoms. Findings were similar across the different
aspects of functioning. Mainly moderate effect sizes were
seen for 6-month changes in the ICF Core Set for RA,
especially in patients with improved health status, with
similar effect size for disease activity. The components in
the ICF Core Set for RA were only weakly associated with
patient-reported outcomes and disease activity.
Conclusions: The ICF Core Set for RA demonstrated
moderate responsiveness in this real-life setting of
patients where minor changes occurred during treatment
with DMARDs
A review of the immunomodulating components of maternal breast milk and protection against necrotizing enterocolitis
Breast milk contains immunomodulating components that are beneficial to newborns during maturation of their immune system. Human breast milk composition is influenced by an infant\u27s gestational and chronological age, lactation stage, and the mother and infant\u27s health status. Major immunologic components in human milk, such as secretory immunoglobulin A (IgA) and growth factors, have a known role in regulating gut barrier integrity and microbial colonization, which therefore protect against the development of a life-threatening gastrointestinal illness affecting newborn infants called necrotizing enterocolitis (NEC). Breast milk is a known protective factor in the prevention of NEC when compared with feeding with commercial formula. Breast milk supplements infants with human milk oligosaccharides, leukocytes, cytokines, nitric oxide, and growth factors that attenuate inflammatory responses and provide immunological defenses to reduce the incidence of NEC. This article aims to review the variety of immunomodulating components in breast milk that protect the infant from the development of NEC
Structured Near-Optimal Channel-Adapted Quantum Error Correction
We present a class of numerical algorithms which adapt a quantum error
correction scheme to a channel model. Given an encoding and a channel model, it
was previously shown that the quantum operation that maximizes the average
entanglement fidelity may be calculated by a semidefinite program (SDP), which
is a convex optimization. While optimal, this recovery operation is
computationally difficult for long codes. Furthermore, the optimal recovery
operation has no structure beyond the completely positive trace preserving
(CPTP) constraint. We derive methods to generate structured channel-adapted
error recovery operations. Specifically, each recovery operation begins with a
projective error syndrome measurement. The algorithms to compute the structured
recovery operations are more scalable than the SDP and yield recovery
operations with an intuitive physical form. Using Lagrange duality, we derive
performance bounds to certify near-optimality.Comment: 18 pages, 13 figures Update: typos corrected in Appendi
Universal dielectric loss in amorphous solids from simultaneous bias and microwave field
We derive the ac dielectric loss in glasses due to resonant processes created
by two-level systems and a swept electric field bias. It is shown that at
sufficiently large ac fields and bias sweep rates the nonequilibrium loss
tangent created by the two fields approaches a universal maximum determined by
the bare linear dielectric permittivity. In addition this nonequilibrium loss
tangent is derived for a range of bias sweep rates and ac amplitudes and show
that the loss tangent creates a predicted loss function that can be understood
in a Landau-Zener theory and which can be used to extract the TLS density,
dipole moment, and relaxation rate.Comment: To appear in Physical Review Letters, 4 pages, 3 figure
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