Effect of Fluorination Position on the Crystalline Structure and Stretchability of Intrinsically Stretchable Polymer Semiconductors.

A clear understanding of the structure-property relationship of intrinsically stretchable polymer semiconductors (ISPSs) is essential for developing high-performance polymer-based electronics. Herein, we investigate the effect of the fluorination position on the crystalline structure, charge-carrier mobility, and stretchability of polymer semiconductors based on a benzodithiophene-co-benzotriazole configuration. Although four different polymer semiconductors showed similar field-effect mobilities for holes (µ ≈ 0.1 cm2 V-1 s-1), polymer semiconductors with nonfluorinated backbones exhibited improved thin-film stretchability confirmed with crack onset strain (εc ≈ 20%-50%) over those of fluorinated counterparts (εc ≤ 10%). The enhanced stretchability of polymer semiconductors with a nonfluorinated backbone is presumably due to the higher face-on crystallite ratio and π-π stacking distance in the out-of-plane direction than those of the other polymer semiconductors. These results provide new insights into how the thin-film stretchability of polymer semiconductors can be improved by using precise molecular tailoring without deteriorating electrical properties.

Characteristics of exposure factors and inhalation exposure to selected spray consumer products in Korean population.

Many consumer spray products are sold for various purposes. Use of spray products can cause adverse health effects. This study evaluated exposure factors for consumer spray products and assessed the particle inhalation exposure. Six consumer spray products were evaluated: an automobile interior cleaner, car deodorizing spray, anti-static spray, waterproofing spray, microorganism deodorizer, and disinfectant spray. The exposure factors were based on 10,000 respondents over 15 years old. Inhalation dose was calculated from the concentration released into the room air and time used. The use rates of the spray products ranged from 0.4 to 11% and differed significantly by gender (p < 0.001). Aerosol types had a higher mass per use and longer duration of usage than trigger types. The median concentration of the trigger type ranged from 17.35 to 373.38 mg/m3, while that of the aerosol type ranged from 36.66 to 1601.97 mg/m3. The median inhalation dose of the trigger and aerosol types ranged from 2.04 × 10-3 to 0.20 and 2.60 × 10-3 to 1.71 mg/kg/day, respectively. The inhalation dose of the disinfectant spray increased with the level of education (p < 0.001), while the inhalation doses of the other spray products were not significantly associated with gender, age, income, or education.

Predictors of midpalatal suture expansion by miniscrew-assisted rapid palatal expansion in young adults: A preliminary study.

OBJECTIVE: We sought to determine the predictors of midpalatal suture expansion by miniscrew-assisted rapid palatal expansion (MARPE) in young adults. METHODS: The following variables were selected as possible predictors: chronological age, palate length and depth, midpalatal suture maturation (MPSM) stage, midpalatal suture density (MPSD) ratio, the sella-nasion (SN)-mandibular plane (MP) angle as an indicator of the vertical skeletal pattern, and the point A-nasion-point B (ANB) angle for anteroposterior skeletal classification. For 31 patients (mean age, 22.52 years) who underwent MARPE treatment, palate length and depth, MPSM stage and MPSD ratio from the initial cone-beam computed tomography images, and the SN-MP angle and ANB angle from lateral cephalograms were assessed. The midpalatal suture opening ratio was calculated from the midpalatal suture opening width measured in periapical radiographs and the MARPE screw expansion. Statistical analyses of correlations were performed for the entire patient group of 31 subjects and subgroups categorized by sex, vertical skeletal pattern, and anteroposterior skeletal classification. RESULTS: In the entire patient group, the midpalatal suture opening ratio showed statistically significant negative correlations with age, palate length, and MPSM stage (r = -0.506, -0.494, and -0.746, respectively, all p < 0.01). In subgroup analyses, a strong negative correlation was observed with the palate depth in the skeletal Class II subgroup (r = -0.900, p < 0.05). CONCLUSIONS: The findings of this study indicated that age, palate length, and MPSM stage can be predictors of midpalatal suture expansion by MARPE in young adults.

Effects of Bromelain and Double Emulsion on the Physicochemical Properties of Pork Loin.

Our aim was to investigate the effects of bromelain embedded in double emulsion (DE) on physicochemical properties of pork loin. We evaluated DE characteristics such as size, zeta potential, and microscopy after fabrication. We marinated meat with distilled water (DW), 1% (w/v) bromelain solution, blank DE, and 1% (w/v) bromelain loaded in double emulsion (DE E) for 0, 24, 48, and 72 h at 4°C, and prepared raw meat for control. The marinated samples were assessed for color, water holding capacity, cooking loss, moisture content, pH, protein solubility, Warner-Bratzler shear force (WBSF) and gel electrophoresis. The droplet size of 1% (w/v) bromelain embedded in DE was increased compared with blank DE (p<0.05) and values of zeta potential decreased. The increase in lightness and color difference range of the DE-treated group was lower than that of the DW-treated group (p<0.05). Moreover, treatment by immersion in 1% (w/v) DE E resulted in the highest water holding capacity values (p<0.05) and lower cooking loss values than water base treatment (p<0.05). Results for myofibrillar protein solubility and WBSF showed a similar trend. 1% (w/v) DE E showed degradation of myosin heavy chain after 48 h in sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Thus, bromelain-loaded DE is useful for controlling and handling enzyme activity in food industry.