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The Contact Lens Impact on Quality of Life (CLIQ) questionnaire: development and validation
NoPURPOSE. To develop and validate a questionnaire for the measurement of the impact of contact lenses on quality of life (QoL): The Contact Lens Impact on Quality of Life (CLIQ) Questionnaire. METHODS. The questionnaire was developed and validated using conventional methods and Rasch analysis to assure content validity, repeatability, construct validity, and low respondent burden. Item identification and selection (647 items) were performed with an extensive literature review, professional advice, and lay focus groups. Item reduction used focus groups and data obtained from 161 subjects completing a 90-item pilot questionnaire. Validity and reliability, from data of 128 additional subjects, were assessed using Rasch analysis, intraclass correlation coefficient, and Bland-Altman limits of agreement. RESULTS. A 28-item CLIQ Questionnaire was developed and shown to have good validity and reliability by Rasch analysis statistics: real person separation, 2.02; model person separation, 2.17; reliability, 0.80; root mean square measurement error, 2.73; mean square Ā± SD infit, 1.01 Ā± 0.18; outfit, 1.01 Ā± 0.19. The items (mean score, 49.8 Ā± 4.9) were well targeted to the subjects (mean score, 51.2 Ā± 6.2) with a mean difference of 1.35 (scale range, 0-100) units. Test-retest intraclass correlation coefficient (0.86) and coefficient of repeatability (Ā±8.00 units) demonstrated good repeatability. CONCLUSIONS. Rasch analysis and standard psychometric analyses demonstrated that the 28-item CLIQ Questionnaire is a valid and reliable measure of QoL in contact lens wearers. A scoring algorithm is provided for CLIQ Questionnaire users to convert raw scores into the Rasch analysis-derived linear person measures
Towards the asymmetric synthesis of tetrodotoxin and the design of glutamate- and lipid-based photopharmaceuticals
Resolving the obscuring torus in NGC 1068 with the power of infrared interferometry: Revealing the inner funnel of dust
We present new interferometric data obtained with MIDI (MID infrared
Interferometric instrument) for the Seyfert II galaxy NGC 1068, with an
extensive coverage of sixteen uv points. These observations resolve the nuclear
mid-infrared emission from NGC 1068 in unprecedented detail with a maximum
resolution of 7 mas. For the first time, sufficient uv points have been
obtained, allowing us to generate an image of the source using maximum entropy
image reconstruction. The features of the image are similar to those obtained
by modelling. We find that the mid-infrared emission can be represented by two
components, each with a Gaussian brightness distribution. The first, identified
as the inner funnel of the obscuring torus, is hot (800K), 1.35 parsec long,
and 0.45 parsec thick in FWHM at a PA=-42 degrees (from north to east). It has
an absorption profile different than standard interstellar dust and with
evidence for clumpiness. The second component is 3 by 4 pc in FWHM with T=300K,
and we identify it with the cooler body of the torus. The compact component is
tilted by 45 degrees with respect to the radio jet and has similar size and
orientation to the observed water maser distribution. We show how the dust
distribution relates to other observables within a few parsecs of the core of
the galaxy such as the nuclear masers, the radio jet, and the ionization cone.
We compare our findings to a similar study of the Circinus galaxy and other
relevant studies. Our findings shed new light on the relation between the
different parsec-scale components in NGC 1068 and the obscuring torus.Comment: Accepted to MNRA
A Step-Indexing Approach to Partial Functions
We describe an ACL2 package for defining partial recursive functions that
also supports efficient execution. While packages for defining partial
recursive functions already exist for other theorem provers, they often require
inductive definitions or recursion operators which are not available in ACL2
and they provide little, if any, support for executing the resulting
definitions. We use step-indexing as the underlying implementation technology,
enabling the definitions to be carried out in first order logic. We also show
how recent enhancements to ACL2's guard feature can be used to enable the
efficient execution of partial recursive functions.Comment: In Proceedings ACL2 2013, arXiv:1304.712
Destabilization of Ī±-helical structure in solution improves bactericidal activity of antimicrobial peptides: Opposing effects on bacterial and viral targets
We have previously examined the mechanism of antimicrobial peptides on the outer membrane of vaccinia virus. Here we show that the formulation of peptides LL37 and magainin-2B amide in polysorbate 20 (Tween-20ā¢) results in greater reductions in virus titre than formulation without detergent, and the effect is replicated by substitution of polysorbate 20 with high ionic strength buffer. In contrast, formulation with polysorbate 20 or high ionic strength buffer has the opposite effect on bactericidal activity of both peptides, resulting in lesser reductions in titre for both gram-positive and gram-negative bacteria. Circular dichroism spectroscopy shows that the differential action of polysorbate 20 and salt on the virucidal and bactericidal activities correlates with the Ī±-helical content of peptide secondary structure in solution, suggesting that the virucidal and bactericidal activities are mediated through distinct mechanisms. The correlation of a defined structural feature with differential activity against a host-derived viral membrane and the membranes of both gram-positive and gram-negative bacteria suggests that overall helical content in solution under physiological conditions is an important feature for consideration in the design and development of candidate peptide-based antimicrobial compounds
Refractive error changes in cortical, nuclear, and posterior subcapsular cataracts
AIMS: To determine the effect of the three main morphological types of cataract on refractive error. METHODS: Data were prospectively collected from 77 subjects (age 67 (SD 8) years) with one morphological type of cataract. 34 had cortical, 21 had nuclear, and 21 had posterior subcapsular cataract. 22 subjects with clear lenses (60 (7) years) were recruited as controls. The spherical equivalent and astigmatic vector change between spectacle correction and optimal refraction were calculated. RESULTS: The cortical cataract group showed a significant astigmatic change of 0.71 (0.67) D (mean (1 SD)) compared to the control group (0.24 (0.20) D), with 24% outside the 95% confidence limit (0.63 D). The nuclear cataract group showed a significant myopic shift of -0.38 (0.60) D compared to the control group (+0.02 (0.21) D), with 52% beyond the minus 95% confidence limit (-0.39 D). CONCLUSION: A quarter of subjects with cortical cataract showed larger changes in astigmatism than subjects with clear lenses. This is probably because of the localised refractive index changes along cortical spoke opacities within the pupillary area. The well known myopic shift of nuclear cataract was also demonstrated
The diverse nature of intestinal fibroblasts in development, homeostasis, and disease
Only in recent years have we begun to appreciate the involvement of fibroblasts in intestinal development, tissue homeostasis, and disease. These insights followed the advent of single-cell transcriptomics that allowed researchers to explore the heterogeneity of intestinal fibroblasts in unprecedented detail. Since researchers often defined cell types and their associated function based on the biological process they studied, there are a plethora of partially overlapping markers for different intestinal fibroblast populations. This ambiguity complicates putting different research findings into context. Here, we provide a census on the function and identity of intestinal fibroblasts in mouse and human. We propose a simplified framework consisting of three colonic and four small intestinal fibroblast populations to aid navigating the diversity of intestinal fibroblasts
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