PSS32 Impact of dry eye on everyday life (Ideel) - Symptom bother: Estimating cut-off scores for dry eye severity groups

The aims of the study were to estimate score ranges associated with dry eye severity based on the Impact of Dry Eye on Everyday Life (IDEEL) Symptom Bother (SB) domain, and to evaluate the overall performance of the SB domain

The non-centrosymmetric lamellar phase in blends of ABC triblock and ac diblock copolymers

The phase behaviour of blends of ABC triblock and ac diblock copolymers is examined using self-consistent field theory. Several equilibrium lamellar structures are observed, depending on the volume fraction of the diblocks, phi_2, the monomer interactions, and the degrees of polymerization of the copolymers. For segregations just above the order-disorder transition the triblocks and diblocks mix together to form centrosymmetric lamellae. As the segregation is increased the triblocks and diblocks spatially separate either by macrophase-separating, or by forming a non-centrosymmetric (NCS) phase of alternating layers of triblock and diblock (...ABCcaABCca...). The NCS phase is stable over a narrow region near phi_2=0.4. This region is widest near the critical point on the phase coexistence curve and narrows to terminate at a triple point at higher segregation. Above the triple point there is two-phase coexistence between almost pure triblock and diblock phases. The theoretical phase diagram is consistent with experiments.Comment: 9 pages, 8 figures, submitted to Macromolecule

A qualitative study exploring the health-related quality of life and symptomatic experiences of adults and adolescents with ulcerative colitis

Background: Ulcerative colitis (UC) often first presents during adolescence and early adulthood. Primary symptoms of UC are well known, yet similarities and differences of disease experience in adults and adolescents are not well characterized. Methods: To understand the health-related quality of life (HRQoL) and symptomatic experience of UC, in-depth interviews were conducted in the US with 21 adults (20–70 years) and 14 adolescents (12–17 years). Eligibility and medical history were confirmed by clinician report. A previously conducted literature review and resultant conceptual model informed the discussion guide to explore symptoms and HRQoL. Age appropriate creative tasks (“animal” task and collage) were employed to facilitate discussion. Transcripts and collages were subjected to thematic analysis using ATLAS.ti software. Results: Clinician-reported UC severity included 24% mild, 38% moderate, 38% severe among adults; and 64% mild, 29% moderate, 7% severe among adolescents. Among adults, 52% were female, 67% were white. Among adolescents, 50% were female, 71% were white. During analysis it was noted that all participants reported stomach/abdominal pain. Other key symptoms identified were frequent bowel movements, diarrhea, blood in stools, sudden need for bowel movement, stomach cramping, bloating, and feeling gassy/passing gas (?75% of participants). Key impacts identified were embarrassment, dietary limitations, having to plan around UC, worry/fear, anger, low mood/depression, and relationship with others, (?75% of participants). In creative tasks, animals were chosen to represent their UC and content included in the collages reflected the most commonly discussed themes from the interviews. Only adults discussed feeling dehydrated, while only adolescents discussed the impact of UC on school life. Conclusions: Open-ended interviews highlighted the HRQoL and symptomatic experiences of UC from the patient’s perspective, which were similar between adult and adolescent UC patients

Microphase separation induced by competitive hydrogen bonding interactions in semicrystalline triblock copolymer/homopolymer complexes

Microphase separation through competitive hydrogen bonding interactions in ABC/D triblock copolymer/ homopolymer complexes is studied for the first time. This study investigated self-assembled nanostructures that are obtained in the bulk, by the complexation of a semicrystalline polystyrene-block-poly(4-vinylpyridine)-block-poly(ethylene oxide) (SVPEO) triblock copolymer with a poly(4-vinyl phenol) (PVPh) homopolymer in tetrahydrofuran (THF). In these complexes, microphase separation takes place due to the disparity in intermolecular interactions among PVPh/P4VP and PVPh/PEO pairs. At low PVPh concentrations, PEO interacts relatively weakly with PVPh, whereas in the complexes containing more than 30 wt% PVPh, the PEO block interacts considerably with PVPh, leading to the formation of composition-dependent nanostructures. SAXS and TEM results indicate that the cylindrical morphology of a neat SVPEO triblock copolymer changes into lamellae structures at 20 wt% of PVPh then to disordered lamellae with 40 wt% PVPh. Wormlike structures are obtained in the complex with 50 wt%PVPh, followed by disordered spherical microdomains with size in the order of 40–50 nm in the complexes with 60–80 wt% PVPh. Moreover, when the content of PVPh increases to 80 wt%, the complexes show a completely homogenous phase of PVPh/P4VP and PVPh/PEO with phase separated spherical PS domains. The fractional crystallization behavior in SVPEO and complexes at lower PVPh content was also examined. A structural model was proposed to explain the microphase separation and self-assembled morphologies of these complexes based on the experimental results obtained. The formation of nanostructures and changes in morphologies depend on the relative strength of hydrogen bonding interactions between each component block of the copolymer and the homopolymer