1,044 research outputs found
Advance care planning in cystic fibrosis: Current practices, challenges, and opportunities
AbstractBackgroundStudies in cystic fibrosis (CF) report late attention to advance care planning (ACP). The purpose of this study was to examine ACP with patients receiving care at US adult CF care programs.MethodsChart abstraction was used to examine ACP with adults with CF dying from respiratory failure between 2011 and 2013.ResultsWe reviewed 210 deaths among 67 CF care programs. Median age at death was 29years (range 18–73). Median FEV1 in the year preceding death was 33% predicted (range 13–100%); 68% had severe lung disease with FEV1p=pp=0.55). The frequency of ACP varied significantly among the 29 programs contributing data from four or more deaths.ConclusionsACP in CF often occurs late in the disease course. Important decisions default to surrogates when opportunities for ACP are missed. Provision of ACP varies significantly among adult CF care programs. Careful evaluation of opportunities to enhance ACP and implementation of recommended approaches may lead to better practices in this important aspect of CF care
Possible Origin of Antimatter Regions in the Baryon Dominated Universe
We discuss the evolution of U(1) symmetric scalar field at the inflation
epoch with a pseudo Nambu-Goldstone tilt revealing after the end of exponential
expansion of the Universe. The U(1) symmetry is supposed to be associated with
baryon charge. It is shown that quantum fluctuations lead in natural way to
baryon dominated Universe with antibaryon excess regions. The range of
parameters is calculated at which the fraction of Universe occupied by
antimatter and the size of antimatter regions satisfy the observational
constraints, survive to the modern time and lead to effects, accessible to
experimental search for antimatter.Comment: 10 pages, 1 figur
Multicomplementary operators via finite Fourier transform
A complete set of d+1 mutually unbiased bases exists in a Hilbert spaces of
dimension d, whenever d is a power of a prime. We discuss a simple construction
of d+1 disjoint classes (each one having d-1 commuting operators) such that the
corresponding eigenstates form sets of unbiased bases. Such a construction
works properly for prime dimension. We investigate an alternative construction
in which the real numbers that label the classes are replaced by a finite field
having d elements. One of these classes is diagonal, and can be mapped to
cyclic operators by means of the finite Fourier transform, which allows one to
understand complementarity in a similar way as for the position-momentum pair
in standard quantum mechanics. The relevant examples of two and three qubits
and two qutrits are discussed in detail.Comment: 15 pages, no figure
Photon wave functions, wave-packet quantization of light, and coherence theory
The monochromatic Dirac and polychromatic Titulaer-Glauber quantized field
theories (QFTs) of electromagnetism are derived from a photon-energy wave
function in much the same way that one derives QFT for electrons, that is, by
quantization of a single-particle wave function. The photon wave function and
its equation of motion are established from the Einstein energy-momentum-mass
relation, assuming a local energy density. This yields a theory of photon wave
mechanics (PWM). The proper Lorentz-invariant single-photon scalar product is
found to be non-local in coordinate space, and is shown to correspond to
orthogonalization of the Titulaer-Glauber wave-packet modes. The wave functions
of PWM and mode functions of QFT are shown to be equivalent, evolving via
identical equations of motion, and completely describe photonic states. We
generalize PWM to two or more photons, and show how to switch between the PWM
and QFT viewpoints. The second-order coherence tensors of classical coherence
theory and the two-photon wave functions are shown to propagate equivalently.
We give examples of beam-like states, which can be used as photon wave
functions in PWM, or modes in QFT. We propose a practical mode converter based
on spectral filtering to convert between wave packets and their corresponding
biorthogonal dual wave packets.Comment: 34 pages, 3 figures, minor correction
Mediators of the Link Between Autistic Traits and Relationship Satisfaction in a Non-Clinical Sample
People with ASD have deficits in their social skills and may therefore experience lower relationship satisfaction. This study investigated possible mechanisms to explain whether and how autistic traits, measured with the AQ, influence relationship satisfaction in a non-clinical sample of 195 married couples. More autistic traits were associated with lower relationship satisfaction for husbands but not for wives. Multiple mediation analyses revealed that husbands’ responsiveness towards their wives, trust, and intimacy mediated this link between autistic traits and relationship satisfaction. These findings suggest that autistic traits may hamper men’s relationship satisfaction because they impede relationship-specific feelings and behavior. There was no partner-effect of autistic traits, indicating that more autistic traits do not necessarily influence the partner’s perceptions of relationship satisfaction
Size constancy is preserved but afterimages are prolonged in typical individuals with higher degrees of self-reported autistic traits
Deficits in perceptual constancies from early infancy have been proposed to contribute to autism and exacerbate its symptoms (Hellendoorn et al., Frontiers in Psychology 6:1–16, 2015). Here, we examined size constancy in adults from the general population (N = 106) with different levels of self-reported autistic traits using an approach based on negative afterimages. The afterimage strength, as indexed by duration and vividness, was also quantified. In opposition to the Hellendoorn and colleagues’ model, we were unable to demonstrate any kind of relationship between abilities in size constancy and autistic traits. However, our results demonstrated that individuals with higher degrees of autistic traits experienced more persistent afterimages. We discuss possible retinal and post-retinal explanations for prolonged afterimages in people with higher levels of autistic traits
Age-related increases in parathyroid hormone may be antecedent to both osteoporosis and dementia
<p>Abstract</p> <p>Background</p> <p>Numerous studies have reported that age-induced increased parathyroid hormone plasma levels are associated with cognitive decline and dementia. Little is known about the correlation that may exist between neurological processing speed, cognition and bone density in cases of hyperparathyroidism. Thus, we decided to determine if parathyroid hormone levels correlate to processing speed and/or bone density.</p> <p>Methods</p> <p>The recruited subjects that met the inclusion criteria (n = 92, age-matched, age 18-90 years, mean = 58.85, SD = 15.47) were evaluated for plasma parathyroid hormone levels and these levels were statistically correlated with event-related P300 potentials. Groups were compared for age, bone density and P300 latency. One-tailed tests were used to ascertain the statistical significance of the correlations. The study groups were categorized and analyzed for differences of parathyroid hormone levels: parathyroid hormone levels <30 (n = 30, mean = 22.7 ± 5.6 SD) and PTH levels >30 (n = 62, mean = 62.4 ± 28.3 SD, p ≤ 02).</p> <p>Results</p> <p>Patients with parathyroid hormone levels <30 showed statistically significantly less P300 latency (P300 = 332.7 ± 4.8 SE) relative to those with parathyroid hormone levels >30, which demonstrated greater P300 latency (P300 = 345.7 ± 3.6 SE, p = .02). Participants with parathyroid hormone values <30 (n = 26) were found to have statistically significantly higher bone density (M = -1.25 ± .31 SE) than those with parathyroid hormone values >30 (n = 48, M = -1.85 ± .19 SE, p = .04).</p> <p>Conclusion</p> <p>Our findings of a statistically lower bone density and prolonged P300 in patients with high parathyroid hormone levels may suggest that increased parathyroid hormone levels coupled with prolonged P300 latency may become putative biological markers of both dementia and osteoporosis and warrant intensive investigation.</p
Direct and cross-scheme effects in a research and development subsidy program
This study investigates the effects of an R&D subsidy scheme on participating firms’ net R&D
investment. Making use of a specific policy design in Belgium that explicitly distinguishes
between research and development grants, we estimate direct and cross-scheme effects on research
versus development intensities in recipients firms. We find positive direct effects from research
(development) subsidies on net research (development) spending. This direct effect is larger for
research grants than for development grants. We also find cross-scheme effects that may arise due
to complementarity between research and development activities. Finally, we find that the
magnitude of the treatment effects depends on firm size and age and that there is a minimum
effective grant size, especially for research projects. The results support the view that public
subsidies induce higher additional investment particularly in research where market failures are
larger, even when the subsidies are targeting development
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