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This study investigates the propagation of dark Alfvén solitons in low-β magnetized plasma using Hall-magnetohydrodynamic (Hall-MHD) numerical simulations. The rational solution of the nonlinear Schr o ̈ dinger equation (NLSE) is presented, which is proposed as an effective tool for studying dark envelope solitons in plasma. Our results show a high degree of agreement between numerical simulations and analytical solutions derived from the NLSE via the reductive perturbation method. This agreement validates our modeling and computational approach. In addition, the simulations confirm the existence of dark Alfvén solitons in magnetized plasma. This work demonstrates the effectiveness of Hall-MHD simulations in studying complex plasma phenomena, contributing to the broader understanding of soliton propagation in plasma environments. [ABSTRACT FROM AUTHOR]

ABSTRACT Stimuli-sensitive hydrogels are one of the most promising and versatile materials with many potential applications. In this article, a pH-sensitive hydrogel [P(AA- co-C8PhEO10Mac)] was synthesized by the free-radical cross-linking polymerization of acrylic acid (AA) and octylphenyl polyoxyethylene methacrylate macromonomer (C8PhEO10Mac). Swelling property, swelling, and deswelling kinetics of the hydrogels in different pH media were studied and hydrogel microstructures were investigated by means of scanning electron microscopy (SEM). Theophylline was chosen as a model drug and the controlled-release properties of hydrogels were pilot studied. The results showed that the P(AA- co-C8PhEO10Mac) hydrogel has a porous structure, both the rapid swelling and deswelling rate, and good pH sensitivity characteristics; The swelling ratios of the gels in stimulated intestinal fluids (SIF, pH = 7.4) were higher than those in stimulated gastric fluids (SGF, pH = 1.4). The in vitro cumulative release data were analyzed using an empirical equation to compute the diffusion exponent ( n), whose values suggest a non-Fickian mode of transport. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 1981-1989, 2013 [ABSTRACT FROM AUTHOR]

The author reflects on the documentary film "Our Life Saving Vinegar" which tackles the issue of providing help for sex workers so they can regain their basic labor rights. The abolishment of the licensed prostitute system in Taiwan has made many sex workers unemployed. Some of these women have made a career move by establishing a vinegar production line.

Objective: To explore a gingival shade matching method and to evaluate the precision and accuracy of a dental spectrophotometer modified to be used in gingival color measurement., Methods: Crystaleye, a dental spectrophotometer (Olympus, Tokyo, Japan) with a custom shading cover was tested. For precision assessment, two experienced experimenters measured anterior maxillary incisors five times for each tooth. A total of 20 healthy gingival sites (attached gingiva, free gingiva and medial gingival papilla in anterior maxillary region) were measured,the Commission Internationale de I' Eclairage (CIE) color parameters (CIE L*a*b*) of which were analyzed using the supporting software. For accuracy assessment, a rectangular area of approximately 3 mm×3 mm was chosen in the attached gingival portion for spectral analysis. PR715 (SpectraScan;Photo Research Inc.,California, USA), a spectroradiometer, was utilized as standard control. Average color differences (ΔE) between the values from PR715 and Crystaleye were calculated., Results: In precision assessment,ΔL* between the values in all the test sites and average values were from(0.28±0.16)to(0.78±0.57), with Δa*and Δb* from(0.28±0.15)to (0.87±0.65),from(0.19±0.09)to( 0.58±0.78), respectively. Average ΔE between values in all test sites and average values were from (0.62 ± 0.17) to (1.25 ± 0.98) CIELAB units, with a total average ΔE(0.90 ± 0.18). In accuracy assessment, ΔL* with control device were from(0.58±0.50)to(2.22±1.89),with Δa*and Δb* from(1.03±0.67)to(2.99±1.32),from(0.68±0.78)to(1.26±0.83), respectively. Average ΔE with the control device were from (2.44±0.82) to (3.51±1.03) CIELAB units, with a total average ΔE (2.96 ± 1.08)., Conclusion: With appropriate modification, Crystaleye, the spectrophotometer, has demonstrated relative minor color variations that can be useful in gingival color measurement.

Objective: To investigate the effect of gingival color on spectrophotometric color measurement in a standardized model., Methods: Shofu gingival matrices were used to simulate the soft tissue and VITA Classical shade tabs were fixed into them. Both the gingival matrices and shade tabs were measured with Crystaleye spectrophotometer in a black box. Regions of the shade tabs, gingival color and their combinated effect on measurements were analyzed, Pearson correlation analysis was used to identify the correlation of the gingival color difference with the shade tabs color difference., Results: The ranges of color difference were 1.01-2.26 in the cervical, 0.93-1.27 in the body and 1.67-2.97 in the incisal regions, respectively. Statistical analysis revealed that there was significant difference among all the gingival groups in the cervical region. Color differences were similar in the body and the incisal regions. The color measurement with Crystaleye was influenced by the regions of the shade tabs, the gingival color and their combination (P<0.001). Pearson Correlation Coefficient was 0.646 in the cervical, 0.386 in the body and 0.217 in the incisal regions respectively(P<0.001)., Conclusion: The color measurement in the cervical region with the spectrophotometer was influenced by the color of the simulated gingiva. Such influence was not obvious in the body and incisal regions. Color coordinates changed regularly with the gingival color.

Objective: to develop an in vitro shade-measuring model to evaluate the reliability and accuracy of the Crystaleye spectrophotometric system, a newly developed spectrophotometer., Methods: four shade guides, VITA Classical, VITA 3D-Master, Chromascop and Vintage Halo NCC, were measured with the Crystaleye spectrophotometer in a standardised model, ten times for 107 shade tabs. The shade-matching results and the CIE L*a*b* values of the cervical, body and incisal regions for each measurement were automatically analysed using the supporting software. Reliability and accuracy were calculated for each shade tab both in percentage and in colour difference (ΔE). Difference was analysed by one-way ANOVA in the cervical, body and incisal regions., Results: range of reliability was 88.81% to 98.97% and 0.13 to 0.24 ΔE units, and that of accuracy was 44.05% to 91.25% and 1.03 to 1.89 ΔE units. Significant differences in reliability and accuracy were found between the body region and the cervical and incisal regions. Comparisons made among regions and shade guides revealed that evaluation in ΔE was prone to disclose the differences., Conclusion: measurements with the Crystaleye spectrophotometer had similar, high reliability in different shade guides and regions, indicating predictable repeated measurements. Accuracy in the body region was high and less variable compared with the cervical and incisal regions.