Center Deviation Measurement of Color Contact Lenses Based on a Deep Learning Model and Hough Circle Transform.

Ensuring the quality of color contact lenses is vital, particularly in detecting defects during their production since they are directly worn on the eyes. One significant defect is the "center deviation (CD) defect", where the colored area (CA) deviates from the center point. Measuring the extent of deviation of the CA from the center point is necessary to detect these CD defects. In this study, we propose a method that utilizes image processing and analysis techniques for detecting such defects. Our approach involves employing semantic segmentation to simplify the image and reduce noise interference and utilizing the Hough circle transform algorithm to measure the deviation of the center point of the CA in color contact lenses. Experimental results demonstrated that our proposed method achieved a 71.2% reduction in error compared with existing research methods.

MRI-Based Classification of Rathke's Cleft Cyst and Its Clinical Implication.

BACKGROUND: Rathke's cleft cysts (RCCs) are benign tumors of the pituitary gland. Small, asymptomatic RCCs do not require surgical treatment, whereas surgical treatment is required for symptomatic RCCs. METHODS: We retrospectively reviewed medical records of patients with an RCC who were diagnosed and managed in our institution between April 2004 and April 2020 and generated two different cohorts: the observation (n=114) and the surgical group (n=99). Their initial MRI signal characteristics were analyzed. The natural course focusing on cyst size was observed in the observation group and postoperative visual and endocrine outcomes were evaluated in the surgical group. RESULTS: The characterization of MRI signals of cyst contents in both T1-weighted (T1W) and T2-weighted (T2W) images revealed nine combinations for our 213 patients. Among 115 patients with a high T2W signal, the cysts showed hypo-, iso-, and hyper-intensity on T1W images in 72, 39, and 44 patients, respectively; Type S-low, Type S-iso, and Type S-high. One more major group of 35 patients showed RCCs with hyperintensity on the T1W images and hypointensity on the T2W images named as Type M. In the comparison between observation and surgical groups, we identified only two major groups in which the number of patients in the surgical and observation groups was statistically different: more Type S-low in a surgical group (p<0.001) and more Type M in an observation group (p=0.007). In subgroup analysis, the range of change in the cyst size was the highest in Type S-high in the observation group (p=0.028), and intergroup differences in visual and endocrine outcomes were not evident in the surgical group. CONCLUSION: MRI characteristics help to predict the natural course of RCCs. We identified subgroups of RCCs which are more or less likely to require surgical intervention.

Retreatment of a recurrent giant aneurysm of the internal carotid artery after treatment with a flow-diverting stent.

Flow-diverting stents (FDSs) have proven advantageous for the treatment of large, fusiform, and dissecting aneurysms that are otherwise difficult to treat. Retreatment strategies for recurrent large or giant aneurysms after FDSs are limited to overlapping implantation of an additional FDS or definitive occlusion of the parent vessel. We report a recurrent giant aneurysm that was initially treated with an FDS with coils and was successfully treated with an additional FDS. Visual symptoms due to the mass effect of the recurrent aneurysm were completely resolved, and follow-up digital subtraction angiography revealed complete obliteration of the aneurysm. Additional FDS implantation for the retreatment of incompletely occluded aneurysms after the initial FDS treatment may be feasible and safe. Further studies are required to validate these results.

Engineering Silk Protein to Modulate Polymorphic Transitions for Green Lithography Resists.

Silk protein is being increasingly introduced as a prospective material for biomedical devices. However, a limited locus to intervene in nature-oriented silk protein makes it challenging to implement on-demand functions to silk. Here, we report how polymorphic transitions are related with molecular structures of artificially synthesized silk protein and design principles to construct a green-lithographic and high-performative protein resist. The repetition number and ratio of two major building blocks in synthesized silk protein are essential to determine the size and content of ß-sheet crystallites, and radicals resulting from tyrosine cleavages by the 193 nm laser irradiation induce the ß-sheet to α-helix transition. Synthesized silk is designed to exclusively comprise homogeneous building blocks and exhibit high crystallization and tyrosine-richness, thus constituting an excellent basis for developing a high-performance deep-UV photoresist. Additionally, our findings can be conjugated to design an electron-beam resist governed by the different irradiation-protein interaction mechanisms. All synthesis and lithography processes are fully water-based, promising green lithography. Using the engineered silk, a nanopatterned planar color filter showing the reduced angle dependence can be obtained. Our study provides insights into the industrial scale production of silk protein with on-demand functions.

Morphology Control of Poly(styrene-block-dimethylsiloxane) by Simple Blending with Trimethylsilylated Silicate Nanoparticles.

Trimethylsilylated silicate nanoparticle (termed MQ resin, combining M Me3SiO1/2 and Q SiO4/2 units)/poly(styrene-block-polydimethylsiloxane) (PS-PDMS, 31K-15K, polydispersity PD = 1.15, weight-average molecular weight Mw = 45.5K) blends behave similarly to block copolymers with different PS/PDMS ratios. MQ is localized in the PDMS phase virtually extending the volume fraction in the block copolymer. This allows for microdomain morphology control beyond what can be achieved with the starting block copolymer. Synthesizing siloxane-containing block copolymers targeted at certain equilibrium morphologies can be time-consuming and in some cases technically challenging. This work shows that MQ is a robust morphology modifier, not limited by the occurrence of surface segregation and the high diffusion rates typically associated with homopolymer modification, as confirmed by looking at the PDMS/PS-PDMS reference. The convenient and robust structure control MQ nanoparticle modification of PS-PDMS provides could overcome one of the hurdles to adoption of block copolymer lithography.

Nanoscale composition of biphasic polymer nanocolloids in aqueous suspension.

The molecular distribution in nanocolloids of poly(dimethyl siloxane) (PDMS) and an organic copolymer (methyl acrylate co-methyl methacrylate co-vinyl acetate) preserved in a frozen aqueous solution was investigated using cryovalence electron energy-loss spectroscopy (EELS) coupled with a scanning transmission electron microscope. Low energy-loss spectra depend upon valence electron structure, and we show that they are substantially different for the PDMS, the copolymer, and the vitrified water studied here. Combining a high efficiency detection system and the use of high-signal low-loss spectra in EELS, we achieved a spatial resolution of 8 nm without serious beam-induced specimen damage in this radiation-sensitive soft-materials system. To obtain quantitative phase maps of silicone and copolymer composition within individual nanoparticles, spectrum datasets were processed via multiple least squares fitting. Quantitative line profiles from the resulting compositional maps indicate that the PDMS lobe of biphasic nanoparticles contained a significant amount of the copolymer and a diffuse interface was formed. Since the nanoparticle synthesis involves polymerization of acrylate monomer dissolved in PDMS nanoparticle precursors, these results suggest that the evolution of the nanocolloid morphology during synthesis is kinetically frozen as the acrylate copolymer achieves some critical molecular weight.

Diffuse polymer interfaces in lobed nanoemulsions preserved in aqueous media.

Using valence electron energy loss spectroscopy (EELS) in the cryo-scanning transmission electron microscopy (STEM), we found that the polymer-polymer interface in two-phase nanocolloids of polydimethyl siloxane (PDMS) and copolymer (methyl acrylate (MA)-methyl methacrylate (MMA)-vinyl acetate (VA)) preserved in water was diffuse despite the fact that equilibrium thermodynamics indicates it should only be on the order of a few nanometers. The diffuse interface is a result of the kinetic trapping of the copolymer within the PDMS phase, and this finding suggests new nonequilibrium pathways to control interfaces during the synthesis of multicomponent polymeric nanostructures.