3,456 research outputs found
Origin and stability of the dipolar response in a family of tetragonal tungsten bronze relaxors
A new family of relaxor dielectrics with the tetragonal tungsten bronze
structure (nominal composition Ba6M3+Nb9O30, M3+ = Ga, Sc or In) were studied
using dielectric spectroscopy to probe the dynamic dipole response and
correlate this with the crystal structure as determined from powder neutron
diffraction. Independent analyses of real and imaginary parts of the complex
dielectric function were used to determine characteristic temperature
parameters, TVF, and TUDR, respectively. In each composition both these
temperatures correlated with the temperature of maximum crystallographic
strain, Tc/a determined from diffraction data. The overall behaviour is
consistent with dipole freezing and the data indicate that the dipole stability
increases with increasing M3+ cation size as a result of increased
tetragonality of the unit cell. Crystallographic data suggests that these
materials are uniaxial relaxors with the dipole moment predominantly restricted
to the B1 cation site in the structure. Possible origins of the relaxor
behaviour are discussed.Comment: Main article 32 pages, 8 figures; Supplementary data 24 pages, 4
figure
Japanese version of the family dermatology life quality index: translation and validation
Skin conditions affect the quality of life (QoL) of patients and their family. To assess family members' QoL, a questionnaire uniquely designed for family members is necessary. We translated the Family Dermatology Life Quality Index (FDLQI), originally created and validated by Basra et al., into Japanese, and evaluated its reliability and validity. For psychometric evaluations, 150 dermatology patients and their family members were included. The Japanese version of the FDLQI showed high testâretest reliability (intraclass correlation coefficient = 0.95) and internal consistency reliability (Cronbach's alpha = 0.86). FDLQI scores significantly correlated with DLQI scores (r = 0.58, P < 0.01, Spearman's rho) and global question (GQ) which measured the patient's skin condition on a visual analog scale (r = 0.36, P < 0.01). Family members of patients with inflammatory skin diseases showed higher FDLQI scores than those with isolated lesions, but the difference was not statistically significant (P = 0.062, MannâWhitney U-test). Responsiveness to change was demonstrated in a group in which the patient's skin condition was assessed as improved (n = 37, r = 0.46, P < 0.01) but not in that in which it became worse. The difference of the change between the two groups was statistically significant (P < 0.01). Additionally, the change in FDLQI scores and GQ were significantly correlated (r = 0.40, P < 0.01). Exploratory factor analysis suggested essential unidimensionality of the instrument. We showed acceptable validity and responsiveness of this Japanese version of FDLQI. Further clinical epidemiological studies are required to confirm this
Predicting total reaction cross sections for nucleon-nucleus scattering
Nucleon total reaction and neutron total cross sections to 300 MeV for 12C
and 208Pb, and for 65 MeV spanning the mass range, are predicted using
coordinate space optical potentials formed by full folding of effective
nucleon-nucleon interactions with realistic nuclear ground state densities.
Good to excellent agreement is found with existing data.Comment: 10 pages, 4 figure
Salmonella Pathogenicity Island 2 Is Expressed Prior to Penetrating the Intestine
Salmonella enterica serovar Typhimurium is a facultative intracellular pathogen that causes disease in mice that resembles human typhoid. Typhoid pathogenesis consists of distinct phases in the intestine and a subsequent systemic phase in which bacteria replicate in macrophages of the liver and spleen. The type III secretion system encoded by Salmonella pathogenicity island 2 (SPI-2) is a major virulence factor contributing to the systemic phase of typhoid pathogenesis. Understanding how pathogens regulate virulence mechanisms in response to the environment, including different host tissues, is key to our understanding of pathogenesis. A recombinase-based in vivo expression technology system was developed to assess SPI-2 expression during murine typhoid. SPI-2 expression was detectable at very early times in bacteria that were resident in the lumen of the ileum and was independent of active bacterial invasion of the epithelium. We also provide direct evidence for the regulation of SPI-2 by the Salmonella transcription factors ompR and ssrB in vivo. Together these results demonstrate that SPI-2 expression precedes penetration of the intestinal epithelium. This induction of expression precedes any documented SPI-2-dependent phases of typhoid and may be involved in preparing Salmonella to successfully resist the antimicrobial environment encountered within macrophages
Comparison of Transfer-to-Continuum and Eikonal Models of Projectile Fragmentation Reactions
Spectroscopic properties of nuclei are accessible with projectile
fragmentation reactions, but approximations made in the reaction theory can
limit the accuracy of the determinations. We examine here two models that have
rather different approximations for the nucleon wave function, the target
interaction, and the treatment of the finite duration of the reaction. The
nucleon-target interaction is treated differently in the eikonal and the
transfer-to-continuum model, but the differences are more significant for light
targets. We propose a new parameterization with that in mind. We also propose a
new formula to calculate the amplitude that combines the better treatment of
the wave function in the eikonal model with the better treatment of the target
interaction in the transfer-to-continuum model.Comment: 21 pages, latex file including 3 tables. 5 figures. Submitted to
Phys. Rev.
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Sexual function and sexual satisfaction following spinal cord injury: an interpretative phenomenological analysis of partner experiences
Purpose
This study explored how partners/spouses of people with Spinal Cord Injury (SCI) experienced intimacy, sexual function, and sexual satisfaction post-SCI.
Materials and methods
Qualitative, semi-structured interviews were conducted with the partners/spouses of people with SCI living in the community in the United Kingdom. Twelve participants (7 females; 5 males) were recruited using purposive sampling. A nine-item semi-structured interview design was used. Interviews were transcribed verbatim and analysed via Interpretative Phenomenological Analysis (IPA).
Results
Three superordinate themes were demonstrated: (1) Stolen sex through unpreparedness; (2) Redefining sex; and (3) Compromised commitment. Partners struggled to come to terms with the shock of radically altered post-SCI sexual relationships, questioning how their changed sexual relationship and sexual identity conflicted with caring requirements. To minimise post-SCI relationship changes, some partners engaged in strategies to protect against, distract from and avoid sexual intimacy, whereas others were able to retain adapted pre-injury patterns of intimate behaviour.
Conclusion
Compromised sexual function and satisfaction significantly disrupt relationship dynamics post-SCI, initiate voluntary celibacy, and limit the perceived viability of continued sexual intimacy. Specialist partner-support provisions are urgently needed, recognising that partner support needs are not restricted to the inpatient rehabilitation phase but importantly extend long past discharge into the community.
Implications for Rehabilitation
Sexual function and satisfaction are highly challenging areas for partners post-spinal cord injury (SCI).
Support and education for the partner must be incorporated into SCI rehabilitation to help with both adjustment and acceptance to changes in sexual functioning post-SCI.
Partner contributions to and experiences of sexual function and satisfaction should be given more value, as these aid in the sustainability of healthy sexual relationships and psychological wellbeing following SCI
Large eddy simulation of turbulence and solute transport in a forested headwater stream
The large eddy simulation (LES) module of the Virtual StreamLab (VSL3D) model is applied to simulate the flow and transport of a conservative tracer in a headwater stream in Minnesota, located in the south Twin Cities metropolitan area. The detailed geometry of the stream reach, which is _135 m long, _2.5 m wide, and _0.15 m deep, was surveyed and used as input to the computational model. The detailed geometry and location of large woody debris and bed roughness elements up to _0.1 m in size were also surveyed and incorporated in the numerical simulation using the Curvilinear Immersed Boundary approach employed in VSL3D. The resolution of the simulation, which employs up to a total of 25 million grid nodes to discretize the flow domain, is sufficiently fine to directly account for the effect of large woody debris and small cobbles (on the streambed) on the flow patterns and transport processes of conservative solutes. Two tracer injection conditions, a pulse and a plateau release, and two cross sections of measured velocity were used to validate the LES results. The computed results are shown to be in good agreement with the field measurements and tracer concentration time series. To our knowledge, the present study is the first attempt to simulate via high-resolution LES solute transport in a natural stream environment taking into account a range of roughness length scales spanning an order of magnitude: From small cobbles on the streambed (_0.1 m in diameter) to large woody debris up to _3 m long. © 2016. American Geophysical Union. All Rights Reserved
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