Search

Heterogeneity in organelle size has been associated with devastating human maladies such as neurodegenerative diseases or cancer. Therefore, assessing the size-based subpopulation of organelles is imperative to understand the biomolecular foundations of these diseases. Here, we demonstrated a ratchet migration mechanism using insulator-based dielectrophoresis in conjunction with a continuous flow component that allows the size-based separation of submicrometer particles. The ratchet mechanism was realized in a microfluidic device exhibiting an array of insulating posts, tailoring electrokinetic and dielectrophoretic transport. A numerical model was developed to elucidate the particle migration and the size-based separation in various conditions. Experimentally, the size-based separation of a mixture of polystyrene beads (0.28 and 0.87

Wearing a face mask is one of the most effective personal protective strategies to diminish the spread of coronavirus disease 2019 (COVID-19). Several dermatological outcomes were reported because of the prolonged use of face masks, especially due to the constant mask-on policy, but the photoprotective effect of face masks has received less attention.The aim of this study was to provide guidance in the use of face masks by comparing the photoprotective effects of routinely used masks.A total of 12 frequently used face masks were tested, including certified respirators, Korea filter (KF)94, KF-anti-droplet (KF-AD), and KF80. The amount of light that penetrates each face mask was measured using a light sensor that can quantify Ultraviolet A (UVA), visible light (VL), and infrared A (IR-A) rays.Black-colored KF94 masks and surgical masks reduced penetration of UVA, VL, and IR-A by approximately 100%. The UVA penetration decreased on average by 95.51%, 90.97%, 85.06%, and 86.41% with white-colored KF94, KF-AD, KF80, and surgical masks, respectively. The VL and IR-A were blocked by approximately 75.58%, 66.16%, 59.18%, and 64.48% with white-colored KF94, KF-AD, KF80, and surgical masks, respectively.In conclusion, the different photoprotective effectiveness of face masks was mainly determined by colors, and therefore, black-colored, multi-layered respirators can be recommended in terms of photoprotection in the COVID-19 pandemic. The quantified comparative results will be helpful to the person with pre-existing photo-aggravated dermatosis, especially in the season of the high intensity of sunlight.

Serial femtosecond crystallography (SFX) is a powerful technique that exploits X-ray free-electron lasers to determine the structure of macromolecules at room temperature. Despite the impressive exposition of structural details with this novel crystallographic approach, the methods currently available to introduce crystals into the path of the X-ray beam sometimes exhibit serious drawbacks. Samples requiring liquid injection of crystal slurries consume large quantities of crystals (at times up to a gram of protein per data set), may not be compatible with vacuum configurations on beamlines or provide a high background due to additional sheathing liquids present during the injection. Proposed and characterized here is the use of an immiscible inert oil phase to supplement the flow of sample in a hybrid microfluidic 3D-printed co-flow device. Co-flow generation is reported with sample and oil phases flowing in parallel, resulting in stable injection conditions for two different resin materials experimentally. A numerical model is presented that adequately predicts these flow-rate conditions. The co-flow generating devices reduce crystal clogging effects, have the potential to conserve protein crystal samples up to 95% and will allow degradation-free light-induced time-resolved SFX.

Three-dimensional (3-D) analysis of human epidermal melanocytes is required for deeper understanding of melanocytic disorders. The purpose of this study was to standardize 3-D imaging and quantification for the evaluation of epidermal melanocytes. The epidermal specimen was obtained using the suction blister method from a patient with melanocytic nevus on the forearm skin. Cutaneous ACT-PRESTO, the tissue-clearing and labeling technique, was subsequently performed. With the 3-D image analysis program, morphological reconstruction and quantification of selected perilesional and melanocytic nevus areas were possible. The region of melanocytic nevus showed higher numbers of total melanocytic dendrites and similar numbers of cell bodies compared with perilesional area. In addition, the mean area and volume of cell bodies increased in the melanocytic nevus area compared with the results in the perilesional area. The 3-D evaluation method of human epidermal melanocytes can be applied to investigate novel pathologies related to hyper- or hypo-pigmentary disorders.

Background Several experimental methods for evaluating dermal structures exist; however, most of these are not used in dermatology clinics because of cost and functional limitations. Objective To propose a simple, non-invasive method for dermal structure evaluation using a green light-emitting diode (LED) with cross-polarized light (CPL) imaging and compare the quality of the images taken using either green or white LED. Materials and methods Skin specimens were taken from fifteen cadavers. Images were captured using CPL photography with a green or white LED. The Commission International d'Eclairage L*a*b* (CIELAB) values were calculated for each image. The skin specimens were processed and stained with Masson's trichrome to visualize collagen fibers with major image scattering. The images were histologically analyzed, and correlational and regression analyses were performed to determine the relationship between the L* values and histologic measurements. Results The L* values for the green images were positively correlated with collagen fiber density, reticular collagen bundle diameter, and dermal thickness. They were effective for estimating dermal properties. The L* values for the white images were positively correlated with reticular collagen bundle diameter and dermal thickness. Correlational coefficients for white images were lower than those for green images. In regression analysis, green images showed a higher coefficient of determination (R2 ) for predicting reticular collagen bundle diameter than white images (0.1128 vs. 0.0827). Conclusion Cross-polarized light imaging with a green LED is a simple, non-invasive method for evaluating dermal structures. The use of a green LED was also more effective for image analysis.

A styrene-butadiene-styrene (SBS) block copolymer was utilized to fabricate the wrinkle pattern in accordance with the buckling theory, and ion-beam (IB) irradiation was applied to induce surface r...

Pityriasis rosea (PR) is a papulosquamous eruption with generally unknown origin but suspected to be related to viral etiologies. The clinicopathological spectrum of several disorders with viral etiologies has been altered after the coronavirus disease 2019 (COVID-19) pandemic. The author group could experience coherent histological alterations in PR after the COVID-19 pandemic. This study aimed to investigate how the clinicopathological findings of PR were changed after the COVID-19 pandemic.Patients (n = 11) diagnosed with PR based on the clinical manifestations and skin biopsies between February 2018 and October 2019 and 11 patients in February 2020 and October 2021 were retrospectively analyzed by investigating the medical records.The patients with PR during the COVID-19 pandemic demonstrated statistically significant histopathological alterations from classic brisk and dense infiltration pattern to dormant and sparse infiltration and psoriasiform-dominant patterns (In conclusion, PR demonstrated a significant histopathological alteration with more frequent pruritus during the COVID-19 pandemic. The comparative results about clinicopathological findings of PR will provide a useful reference for dermatologists in the diagnostic process of PR in the COVID-19 pandemic.

Nasopharyngeal swabs have been widely to prevent the spread of coronavirus disease 2019 (COVID-19). Nasopharyngeal COVID-19 testing is a generally safe and well-tolerated procedure, but numerous complications have been reported in the media. Therefore, the present study aimed to review and document adverse events and suggest procedural references to minimize preventable but often underestimated risks. A total of 27 articles were selected for the review of 842 related documents in PubMed, Embase, and KoreaMed. The complications related to nasopharyngeal COVID-19 testing were reported to be rarely happened, ranging from 0.0012 to 0.026%. Frequently documented adverse events were retained swabs, epistaxis, and cerebrospinal fluid leakage, often associated with high-risk factors, including severe septal deviations, pre-existing skull base defects, and previous sinus or transsphenoidal pituitary surgery. Appropriate techniques based on sufficient anatomical knowledge are mandatory for clinicians to perform nasopharyngeal COVID-19 testing. The nasal floor can be predicted by the line between the nostril and external ear canal. For safe testing, the angle of swab insertion in the nasal passage should remain within 30° of the nasal floor. The swab was gently inserted along the nasal septum just above the nasal floor to the nasopharynx and remained on the nasopharynx for several seconds before removal. Forceful insertion should be attempted, and alternative examinations should be considered, especially in vulnerable patients. In conclusion, patients and clinicians should be aware of rare but possible complications and associated high-risk factors. The suggested procedural pearls enable more comfortable and safe nasopharyngeal COVID-19 testing for both clinicians and patients.

Background Proper assessment of dermal collagen fibers by dermatologists and researchers is essential. Histologic evaluation methods have limitations. We present a simple method for measurement of collagen fibers in human skin using Masson's trichrome staining. Materials and methods Normal skin specimens from a cadaver were processed with Masson's trichrome, which can effectively stain collagen fibers blue with aniline dye. Optical photomicrographs of these slides were analyzed using ImageJ software. Color image processing, a histogram-based function of ImageJ for image segmentation, was performed with color moments thresholding technique. We selected blue areas by adjusting the blue channel to include specific values. The selected areas were highlighted and evaluated. We divided the image into layers of 0.09-mm2 areas from the top to bottom of the dermis. Each area was cropped and evaluated. Results Quantitative assessment yielded the quantitative size occupied by collagen fibers in an area of 0.09 mm2 . Calculation of the percentage in each area can be used to determine the density of collagen fibers. Conclusion Measurements obtained with our method can be applied to research on dermal collagen fibers. We present a convenient quantitative assessment method for the dermal constituents in Masson's trichrome-stained slides.

Decellularization of tissues provides extracellular matrix (ECM) scaffolds for regeneration therapy and an experimental model to understand ECM and cellular interactions. However, decellularization often causes microstructure disintegration and reduction of physical strength, which greatly limits the use of this technique in soft organs or in applications that require maintenance of physical strength. Here, we present a new tissue decellularization procedure, namely CASPER (Clinically and Experimentally Applicable Acellular Tissue Scaffold Production for Tissue Engineering and Regenerative Medicine), which includes infusion and hydrogel polymerization steps prior to robust chemical decellularization treatments. Polymerized hydrogels serve to prevent excessive damage to the ECM while maintaining the sophisticated structures and biological activities of ECM components in various organs, including soft tissues such as brains and embryos. CASPERized tissues were successfully recellularized to stimulate a tissue-regeneration-like process after implantation without signs of pathological inflammation or fibrosis in vivo, suggesting that CASPERized tissues can be used for monitoring cell-ECM interactions and for surrogate organ transplantation.

This study aimed to explore pharmacokinetics, pharmacodynamics, and safety/tolerability of MT921, an injectable cholic acid, after a single subcutaneous administration to healthy volunteers. A randomized, double-blinded, placebo-controlled, single dose-ascending phase 1 study enrolled 24 subjects who were assigned to three groups (60 mg, 120 mg, and 150 mg) of MT921. Blood samples were obtained for a 24-h period before and after injecting MT921 to the submental fat area. Plasma concentrations of cholic acid and deoxycholic acid were determined for pharmacokinetic analysis. Levels of free fatty acid, triglyceride, and total cholesterol were measured for pharmacodynamic analysis. Safety and tolerability were assessed until 21 days post-dose. While systemic exposure to cholic acid tended to increase as the MT921 dose increased, pharmacokinetic profiles of deoxycholic acid were similar among dose groups without showing significant changes. Pharmacodynamic profiles were comparable when measured at baseline and post-dose. The most frequent adverse events were injection site pain and edema. All adverse drug reactions resolved without treatment. MT921 appeared to be well-tolerated after an injection to the submental area at a dose up to 150 mg. Systemic exposure to cholic acid increased as the dose increased. Blood lipid profiles and deoxycholic acid levels were not affected by MT921 treatment.

We investigated homogeneous liquid crystal alignment on hafnium strontium oxide films deposited by a solution process, where the liquid crystal alignment was induced by ion-beam irradiation. Uniform liquid crystal alignment was achieved on the HfSrO films grown at 300 °C. We confirmed the effect of surface morphology and chemical composition of HfSrO films using field-emission scanning electron microscopy and X-ray photoelectron spectroscopy. In addition, we observed the electro-optical characteristics of the twisted-nematic liquid crystal cells based on hafnium strontium oxide films to verify the possibility of their application in liquid crystal displays.

The volume imaging of intact organs/tissues with singlecell resolution provides fundamental understanding of 3-dimensional (3D) organization of biological specimens. It will also improve our knowledge about generation and progression of diseases with chronic debilitating process such as neurodegenerative diseases or cancers, which is certainly helpful to the development of next generation diagnostic or treatment methods (Renier et al., 2014; Tainaka et al., 2014). The conventional approaches for volume imaging require physical section of biological tissues and subsequent multiple processing of images, because the technically accessible depth for acquiring tissue information (e.g., structure, protein distribution, etc.) is limited within hundreds of micrometers primarily due to the diffusion limit of the macromolecule probes (e.g., antibody) and the light scattering (Helmchen & Denk, 2005; Tang et al., 2012; Tomer et al., 2014). Therefore, the conventional approaches for volume imaging are laborintensive, time-consuming, requiring specialized apparatus, and essentially error-prone (Gong et al., 2013; Kim et al., 2014; Li et al., 2010). The recent advent of tissue clearing and labeling methods have been substantially resolved the above-mentioned obstacles through selective removal of lipid component in target tissues or organs without loss of the original protein

Three-dimensional microscopy provides more extended depth of penetration compared with conventional light microscopy and is known to be useful in clinical evaluation of thick biological specimens. Skin nerve biopsy together with the quantification of intraepidermal nerve fibers in multiple thick sections has been widely adopted for evaluating peripheral neuropathies. The aim of the present study was to evaluate the effectivity of three-dimensional microscopy in reducing the required time and inter-rater discrepancies, especially in the case of personnel not familiar with the quantification methods. A total of six cryo-sectioned specimens were analyzed for the study and the skin samples were collected from one patient with postherpetic neuralgia who voluntarily participated in the study. Two investigators, a physician and non-physician assessed the intraepidermal nerve fiber densities and required analysis time using three different methods including direct visualization of tissue slides, and analysis with two- and three-dimensional images. Three-dimensional microscopy could produce images that enabled reliable evaluation of intraepidermal nerve fibers; the accuracy of analysis was statistically comparable between the physician and non-physician (p > .05). Three-dimensional microscopy also enabled the non-physician to proceed meaningfully faster evaluation compared with the direct visualization method (p = .03). Three-dimensional microscopy could be one of the useful methods to improve accuracy and convenience of the analysis of intraepidermal nerve fibers especially appropriate for unaccustomed physician or non-physician. RESEARCH HIGHLIGHTS: Three-dimensional microscopy is capable of producing images with more extended depth of penetration compared with conventional light microscopy and has been known to be suitable for clinical evaluation of thick biological specimens. Cutaneous nerve biopsy and the quantification of nerve fibers in thick sections has been widely adopted for evaluating peripheral neuropathies. Three-dimensional microscopy could be especially appropriate for unaccustomed physician or non-physician to improve accuracy and convenience of the analysis of intraepidermal nerve fibers.

It is well known that doping nanoparticles (NPs) in liquid crystals (LCs) can easily change the physical and electro-optical properties of LC mixture. In this paper, we demonstrate homogeneous, aligned nematic LC (N-LC) system dispersed in iron oxide (Fe2O3) NPs. The prepared Fe2O3 NPs have an average particle size of 50 nm. By changing the doping concentration of Fe2O3 NPs, we observed the characteristics of LC systems. Electrooptical (EO) characteristics included faster rising and falling times (2.14 ms and 10.24 ms, respectively) and lower driving voltage (1.45 V) compared with a pure N-LC cell. We demonstrated these results via the relationship between dielectric con- stant and LC device properties. The results were verified by software simulation based on general physical properties. Moreover, we observed that LC system with Fe2O3 NPs could be accomplished without capacitance hysteresis by capturing charged impurities. Superior performance of LC cell with Fe2O3 NPs indicates that the proposed LC system have strong potential for use in the production of advanced LC displays.

The use of ablative lasers based on the fractional approach is a novel strategy for the treatment of postoperative and acne scars in addition to wrinkles.To evaluate and compare the efficacy of carbon dioxide ablative fractional laser (AFL) and the pulsed dye laser (PDL) for the improvement of surgical scars.Fourteen Korean patients with surgical scars were enrolled for this study. Half of each scar was treated with a 10,600-nm AFL and the contralateral half with the 595-nm PDL. For early intervention of the postoperative scar, the laser treatments were begun after 2 weeks from the Mohs micrographic surgery.Both PDL and AFL produced statistically significant improvements. However, comparatively, there was no statistical difference between them. In each variable, AFL was more effective than PDL in the improvement of pliability and thickness. In contrast, PDL was superior to AFL in the improvement of vascularity and pigmentation.Pulsed dye laser and AFL treatments for surgical scar provide significant improvement. Pulsed dye laser was more effective in color of scar compared with AFL, which showed marked improvement in the contour of scar. Overall improvement was not statistically different in the Vancouver Scar Scale.

Homogeneously aligned twisted nematic liquid crystals (TN-LCs) were produced on molybdenum trioxide (MoO3) thin films via ion beam (IB) irradiation. Control of the pretilt angle was achieved by varying the IB incident angle. X-ray photoelectron spectroscopy (XPS) analysis revealed that the intensity of the Mo-O and O-Mo bonds at various IB incident angles exhibited the tendency that was opposite to that of the pretilt angle and the lowest intensity was produced at 45°. Superior electro-optical (EO) characteristics were also observed. Furthermore, a TN-LC cell fabricated with the MoO3 thin films exhibited high thermal stability. Such stability could be maintained at temperatures greater than 150 °C.

Background The quantitative difference of the light reflected from a skin surface can be analyzed using parallel-polarized light (PPL) photography when combined with an analytic technique similar to colorimetric photography. Objective To improve the PPL photography technique as an assessment tool for the evaluation of skin condition using light-emitting diodes (LED) of different colors. Method Parallel-polarized light images were taken using white and green LED illuminators. The acquired images were transformed to CIELAB coordinates. An in-house skin conductance meter was constructed to assess skin hydration level. A dermatologist evaluated the clinical grading of dryness and glossiness. These clinical severities were also compared statistically with the CIELAB values. Results As with the green illuminator, the correlation analysis of whole sites showed that the L* value positively correlated with age (r = 0.18677, P

We report the doping effect of graphene quantum dots (QDs) in a nematic liquid crystal (NLC) device. The use of graphene QDs leads to improved electro-optical (EO) properties, such as faster response times and a decreased threshold voltage. A 14.8% reduction in the threshold voltage (3.165 V), a 30% decrease in the falling time (4.9 ms) and a 63.6% decrease in the rising time (2.4 ms) were observed for twisted nematic (TN) LC devices (LCDs) that were doped with QDs. We confirm that the doping of the TN-LCD with graphene QDs reduces the field-screening effect, which is caused by impurity ions, whereas the other properties of conventional TN-LCDs are maintained.

Recently, rubbing-free methods have been studied for liquid crystal (LC) alignment; layers generated via such methods have excellent electrical and optical characteristics compared with those obtained using the rubbing method. 1‐3 The rubbing method is a very simple process; however, this process leads to degradation of the surface quality of the alignment layer because of the direct contact of the rubbing machine fabric with the layer and the generation of electrostatic charges and debris between the sample and the rubbing machine fabric. 4‐6 In contrast, alternative methods based on non-contact process such as the ultraviolet (UV) photoalignment technique, 7 oblique deposition, 8 andion-beamirradiation 9‐12 inducefewsurfacedefectsof LC alignment layer compared with that fabricated using the rubbing method. Ion-beam irradiation is commonly used for both inorganic and organic materials; however, this technique is especially useful for inorganic alignment layers. Previously, our research group studied inorganic-based LC alignment layers using ion-beam irradiation; Ta2O5, 13 Al2O3, 14 and HfO2 15 were used for the LC alignment layer rather than rubbed-polyimide. ZrO2 has been studied for use in diverse applications such as gate insulators, sensors, and displays because of its high dielectric constant (∼25), large bandgap (∼5.1 eV), and low standard electrode potential (SEP) (−1.45 V). It has been reported that adding HfO2 to ZrO2 enhances the insulating characteristics of the material by reducing the amount of oxygen vacancies. Furthermore, ZrO2 and HfO2 have the same structure, are located in the same column in the periodic table, and have almost the same atomic radius; thus, their mixture causes no structural defects. 16 Conventional inorganic-based alignment layers typically require the use of sputtering equipment in a vacuum environment. 13‐15,17 In contrast, a solution-process offers the advantages of a relatively simple process, low cost, and easy composition ratio control of the multicomponent materials. 18 Especially, multicomponent materials with variousmoleratioscanbeeasilydepositedthroughtheirsimultaneous addition to the solvent under solution process. In addition, solutionprocessed ZnO has already been evaluated for use as an LC alignment layer in previous study and its performance was similar to that of ZnO deposited by sputtering. 19 In this study, we introduce solution-processed HfZrO-based LC cells created via ion-beam irradiation. The surface of the HfZrO film and optical characteristics of the LC cells for various Hf atomic mole ratios were investigated.

We investigated the use of solution-derived nanocrystalline SnO2 films to promote the self-alignment of liquid crystal (LC) molecules. Uniform and homogeneous LC alignment was spontaneously achieved by using these substrates. LC molecules with a preferred orientation were aligned along the filling direction, and the LC alignment was maintained via van der Waals force by nanocrystals of the solution-derived SnO2 films. This phenomenon did not occur in amorphous-phase SnO2 films. Nanocrystalline SnO2 films were grown at annealing temperatures greater than 400 °C. Although the average transmittances of the SnO2 films degraded slightly as the annealing temperature increased, the values were similar to those of conventional polyimide films. Electrically controlled birefringence mode cells fabricated using the solution-derived nanocrystalline SnO2 films exhibited superior electro-optical characteristics, indicating that this approach will allow the fabrication of advanced LC displays with high performance through a simple fabrication process.

Background and purpose Cutaneous nerve biopsies based on two-dimensional analysis have been regarded as a creditable assessment tool for diagnosing peripheral neuropathies. However, advancements in methodological imaging are required for the analysis of intact structures of peripheral nerve fibers. A tissue-clearing and labeling technique facilitates three-dimensional imaging of internal structures in unsectioned, whole biological tissues without excessive time or labor costs. We sought to establish whether a tissue-clearing and labeling technique could be used for the diagnostic evaluation of peripheral neuropathies. Methods Five healthy individuals and four patients with small-fiber neuropathy (SFN) and postherpetic neuralgia (PHN) were prospectively enrolled. The conventional methods of indirect immunofluorescence (IF) and bright-field immunohistochemistry (IHC) were adopted in addition to the tissue-clearing and labeling method called active clarity technique-pressure related efficient and stable transfer of macromolecules into organs (ACT-PRESTO) to quantify the intraepidermal nerve-fiber density (IENFD). Results The mean IENFD values obtained by IF, bright-field IHC, and ACT-PRESTO in the healthy control group were 6.54, 6.44, and 90.19 fibers/mm², respectively; the corresponding values in the patients with SFN were 1.99, 2.32, and 48.12 fibers/mm², respectively, and 3.06, 2.87, and 47.21 fibers/mm², respectively, in the patients with PHN. Conclusions This study has shown that a tissue-clearing method provided not only rapid and highly reproducible three-dimensional images of cutaneous nerve fibers but also yielded reliable quantitative IENFD data. Quantification of the IENFD using a tissue-clearing and labeling technique is a promising way to improve conventional cutaneous nerve biopsies.

Electrical performance of thin-film transistors (TFTs) is important for their applications. Solution-processed TFTs have low mobility and high sub-threshold swings (S.Ss) because there are many pores and pin-holes in the films. These characteristics are attributed to electron trapping in the YInZnO (YIZO) channel, the SiO2 gate insulator, or their interface. We fabricated hybrid YIZO TFTs with and without UV radiation, and observed that UV-curing of the film affected TFT performance through promoting a response to reactive mesogen (RM). The UV irradiated TFT showed better performance because of the alignment of the channel materials in the source-drain direction. © The Author(s) 2015. Published by ECS. This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 License (CC BY, http://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse of the work in any medium, provided the original work is properly cited. [DOI: 10.1149/2.0031503ssl] All rights reserved.

We propose a multi-walled carbon nanotube (MWCNT)-doped liquid crystal (LC) device with enhanced electro-optical properties. MWCNT-doped LC cells were successfully operated as a twisted nematic LC device with high performance. The LC cells fabricated with MWCNT-doped LCs and a polyimide layer exhibited the best electro-optical properties, such as a low threshold voltage (1.60 V) and fast response time (13.95 ms). MWCNT doping decreased the pre-tilt angles of LC mixtures. Additionally, UV-visible transmittances and photomicrograph images of LC cells indicated LCD application potential with clear and uniform LC alignment.

Effect of multi-stacked layer (MSL), 0.1 mol (M) and 0.3 mol (M) hafnium oxide () alignment layers were fabricated via a solution-process for LCs orientation. The solutions were spin-coated and annealed in a furnace. MSL consists of three sub-layers using 0.1 M solution, mono-layer (ML) is composed of 0.3 M solution. Then ion-beam irradiation was treated with 1.8 keV for 2 min. -based LC cells were investigated through photographs, pre-tilt angle using crystal rotation method, X-ray photoelectron spectroscopy (XPS) measurement, and surface roughness using atomic force microscopy(AFM) for their characteristic research. Good LC orientation characteristics were observed on MSL surface. The LC alignment mechanism on MSL and ML surfaces was attributed to van der Waals (VDW) interaction between the LC molecular and substrate surface.

In this paper we present the characteristics of molar concentration-dependent zinc oxide (ZnO) inorganic films deposited by the solution process for application in liquid crystal displays. ZnO surfaces supported homogeneously aligned liquid crystal (LC) molecules based on an ion-beam (IB) irradiation system. Uniform LC alignment was obtained at ZnO molar concentrations greater than 0.25 mol l−1. X-ray photoelectron spectroscopic (XPS) analysis revealed that changes in the orientation of LC molecules occurred on the ZnO layer. The electro-optic characteristics of the aligned homogenous LCs and twisted nematic (TN) mode based on the ZnO layer were comparable to those based on polyimide, which showed good potential as ZnO surfaces as an alignment layer.

Aim Most studies about the structures of the human skin have been on the general histologic features of the skin. The purpose of this study was to understand the relationship between the microrelief (MR) pattern and histologic structure of the human skin, and to find the usefulness of the three-dimensional reconstruction (3DR) technique of pathological skin tissue. Materials, Subjects, and Methods Human skin specimens were obtained from the medial forearm, abdomen, and volar aspects of the finger tips of cadavers. Two-dimensional surface-viewed images of the skin showing MR patterns were obtained using dry dermoscopy. Histologic structures of the skin were evaluated by 3D images obtained using the 3DR technique. Results MR was deeper and wider in the abdomen than in the medial side of the forearm. In the medial side of the forearm, 10.27 rete ridges were distributed in a plateau, on average. In the abdomen, about 14.37 rete ridges were distributed in a plateau. From 3DR technique, MR pattern thought to be a superordinate concept to rete ridges. Conclusion The 3DR technique was useful and may allow a better understanding of the pathogenetic changes in the skin surface in aging skin.

Aged skin is reported to be associated with unattractive skin color changes and solar elastosis. However, comparative studies have not documented the possible correlation between the two factors. This study investigated the plausible relationship between the facial skin color of elderly Asians and solar elastosis. A total of 22 skin specimens were collected from 22 Korean patients who underwent cheek skin biopsies. Skin color was quantitatively measured using colorimetric photography techniques to produce CIE L*a*b* values; the degree of solar elastosis was quantifiably assessed using a histologic grading scale. These values were used to investigate a correlation between the CIE L*a*b* coordinates and solar elastosis grade. The solar elastosis grade increased according to patient age (r = 0.67, p = .0006). However, the extent of solar elastosis was not statistically correlated with the CIE L*a*b* values, including L*, a*, and b* (r = 0.02, p = .95; r = 0.15, p = 0.50; r = -0.07, p = 0.76, respectively). The results showed that the solar elastosis grade increased, according to patient age, because of cumulative actinic damage. However, colorimetric skin color data did not correlate with the degree of solar elastosis. Therefore, cutaneous color changes and solar elastosis are separate, age-related phenomena. Physicians should be aware of the possible histologic changes in actinically damaged facial skin, regardless of the skin color.

The degenerative calcification of bioprosthetic heart valves remains a clinical challenge, especially among young adults and children. Animal models that are based on subcutaneous and intramuscular implantation and are typically used to assess interventions to prevent bioprosthetic heart valve calcification do not reflect actual hemodynamic stress and lack direct blood contact. Thus, the study aim was to investigate bioprosthesis calcification at different implantation sites.The calcification degrees of five valve implantation methods, namely subcutaneous, intramuscular and intravenous implantation, and arterial and venous patch angioplasty, were simultaneously investigated in 10 New Zealand White rabbits.Ultrasonography and computed tomography images showed vascular patency to be well maintained in all implanted vessels. Histologically, cellular infiltrates around the implant and within the collagen fibers were only found in the intravenous implantation group, which also had the highest calcium level among the methods.The present study was the first to compare the degree of calcification after applying five implantation methods simultaneously in one animal species. The rabbit intravenous implantation model, which involved direct contact with blood factors, is expected to serve as a useful animal model for research into the prevention of bioprosthetic heart valve degeneration.

An objective measurement of cutaneous topographical information is important for quantifying the degree of skin aging. Our aim was to improve methods for measuring microrelief patterns using a three-dimensional analysis based on silicone replicas and scanning electron microscope (SEM). Another objective was to compare the results with those obtained using a two-dimensional analysis method based on dermoscopy. Silicone replicas were obtained from forearms, dorsum of the hands and fingers of 51 volunteers. Cutaneous profiles obtained by SEM with silicone replicas showed more consistent correlations with age than data obtained by dermoscopy. This indicates the advantage of three-dimensional topography analysis using silicone replicas and SEM over the widely used dermoscopic assessment. The cutaneous age was calculated using stepwise linear regression, and the result was 57.40-9.47 × (number of furrows on dorsum of the hand) × (width of furrows on dorsum of the hand).

E-mail: khs2004@khu.ac.kr (H.S. Kim), mcheong@khu.ac.kr (M. Cheong)Received June 27, 2012, Accepted July 6, 2012Ionic liquids (ILs) have been extensively investigated as promising alternatives to conventional organicsolvents such as sulfolane and N,N-dimethylformamide for the selective extraction of aromatic hydrocarbonsfrom the C

This report discusses homogeneously aligned liquid crystals (LCs) subjected to ion-beam (IB) irradiation of the amorphous(a)-Al2O3 alignment layer. We studied the relationship between LC alignment and IB alignment conditions acting on homogeneous surfaces. We attained homogeneous LC orientations on a- Al2O3 alignment layer by optimization between the van der Waals interactions caused by Al-O bonding breaking with x-ray photoelectron spectroscopy. The voltage-transmittance characteristics of the twisted nematic – liquid crystal displays (LCDs) on the a-Al2O3 film indicate potential for use as the LC alignment layer in various LCD display applications.

This study demonstrates liquid crystal (LC) alignment on Al2O3 films using the ion-beam (IB) method as well as the optimization of the IB irradiation condition. Uniform LC alignment was achieved at an IB incident energy of 1800 eV with an IB incident angle of 45°, while inferior LC alignments were observed in other tested conditions. The pretilt angles and transmittances of the LC cell were also shown as part of the same trend for the LC alignment states. This result was subject to van der Waals forces which were caused by topographical changes during the IB process.