Metal-Insulator Transition Detection of Vanadium Dioxide Thin Films by Visible Light Reflection.

Vanadium dioxide (VO2)-based thin films have received considerable attention in recent years due to their superior performance in creating next-generation color-rendering materials. The near-room-temperature metal-insulator transition of VO2 promises the advantage of active color tuning in the visible wavelength range. Although various results of dynamic color generation combined with plasmonic nanostructures are currently being investigated, so far, very few studies have addressed the visible-light optical performance of pure VO2 thin films prepared on conventional substrates. This article shows in detail the phase-transition behavior of VO2 thin films in the visible wavelength range of 400-750 nm prepared on glass with subsequent annealing at temperatures of 350, 400, 450, and 500 °C. The results show an anomalous phase transition reducing the overall RGB reflectivity correlated with the crystallization behavior of the VO2 phase and scattering effect. The sample annealed at 350 °C shows the smallest phase transition at 47 °C, correlating with a crystallite size of 7 nm. The blue band reflectivity anomaly after annealing at 450 °C was considered an effect of the secondary reflection. The results of this research could play a huge role in the production of active-switching photonic devices, color-managed reflectors, and temperature indicators.

Hair Growth-Promoting Activities of Glycosaminoglycans Extracted from the Tunics of Ascidian (Halocynthia roretzi).

Throughout the ages, hair has had psychological and sociological importance in framing the personality and general appearance of an individual. Despite efforts to solve this problem, no groundbreaking measures have been proposed. Glycosaminoglycans (GAGs) and associated proteoglycans have important functions in homeostatic maintenance and regenerative processes of the skin. However, little is known about the role of these molecules in the regulation of the hair follicle cycle. Three fractions (F1, F2 and F3) were obtained after separation and purification of GAGs from ascidian tunics. F1 was observed to contain a small amount of amino sugar while high contents of galactose and N-acetylglucosamine were noted in F2 and F3. 2-acetamido-2-deoxy-3-O-(ß-D-gluco-4-enepyranosyluronic acid)-6-O-sulfo-D-galactose (∆Di-6S) and 2-acetamido-2-deoxy-3-O-(ß-D-gluco-4-enepyranosyluronic acid)-4-O-sulfo-D-galactose (∆Di-4S) were the main disaccharide components. F3 exhibited the highest proliferation activity on human follicle dermal papilla (HFDP) cells. In addition, mixed samples (FFM) of F2 and F3 at different concentrations showed peak activities for five days. After cell culture at a concentration of 10 mg/mL and dihydrotestosterone (DHT), the inhibition effect was higher than that for Minoxidil. Application of 10 mg of FFM to the hair of mice for 28 days resulted in a hair growth effect similar to that of Minoxidil, a positive control.

Nutritional quality variation in dried Pacific Oyster (Crassostrea gigas) using hybrid-pump dryer under different heating treatment.

This study explored the potential of using hybrid pump dryer (HPD) to utilize overproduction in aquaculture of oysters, especially during winter. HPD-dried oysters maybe used as amendments for kimchi, a traditional Korean side dish, for possible nutrient source and flavor enhancer. Oysters were subjected to different heating treatments and evaluated for proximate composition, quality characteristics, and antioxidant activities. Lower lipid and higher glycogen content were observed in HPD-dried oysters processed than the samples dried with hot air (HAD). HPD-dried oysters also exhibited lesser browning activity, better surface color, and higher antioxidant activities. Ash, protein, and water activity were slightly affected by heating treatment. VBN and TBARS were found to be higher in HAD-dried oysters, indicating faster spoilage. Applying heat pattern in drying resulted to improved quality characteristics and antioxidant activities and slower degradation of dried oyster products compared to their single-temperature-drying counterparts, especially those dried at high temperatures.

Characterization of hyaluronic acid extracted from Liparis tessellatus eggs grafted with phenolic acids and nisin.

In polymer therapeutics, polymer-based carrier systems conjugated with antioxidants have been synthesized and studied to improve diagnosis and treatment of diseases, such as, in cancer and tumor. The natural bioactive compound hyaluronic acid (HA), which is essential in medical and pharmaceutical fields, is a linear polymer composed of repeating disaccharide units of ß-1,3-N-acetyl glucosamine and ß-1,4-glucuronic acid. In this study, HA fractions of enzyme-assisted glycosaminoglycans (GAGs) extract from Liparis tessellatus eggs were grafted with gallic acid (GA), caffeic acid (CA), and ferulic acid (FA) via a free radical-mediated method, and with nisin via amide bond formation. The modification has been confirmed through FTIR and 1H NMR spectroscopy and quantified by Folin-Ciocalteu and Bradford assay. FTIR spectra of grafted HA samples exhibited the typical phenolic characteristics within 1450-1650 cm-1, and the formation of amide bond in nisin-grafted HA was shown by absorption peak within 1545-1646 cm-1. 1H NMR spectra showed new peaks of phenyl protons at 6.3-7.7 ppm and new peaks at 0.9-2.9 ppm of amino acids residues protons. These results all confirmed the successful grafting of GA, CA, FA and nisin onto the HA backbone extracted from L. tessellatus eggs.

Biocompatibility and structural characterization of glycosaminoglycans isolated from heads of silver-banded whiting (Sillago argentifasciata Martin & Montalban 1935).

Glycosaminoglycans (GAGs) were extracted from heads of silver-banded whiting (SBW) fish and subjected to preliminary biocompatibility testing per ISO 10993: intracutaneous irritation, maximization sensitization, systemic toxicity, and cytotoxicity. When the GAG solution was injected intradermally, the observed irritation was within ISO limits and comparable to a marketed control. There was no evidence of sensitization, systemic toxicity, or cellular toxicity on the test organisms treated with the GAG mixture from SBW fish heads. Fractionation by size-exclusion chromatography has shown three distinct fractions: F1 as low molecular weight hyaluronic acid (190 kDa), F2 (82 kDa) and F3 (64 kDa), both as chondroitin sulfates. Structural characterization by 1D and 2D nuclear magnetic resonance spectroscopy and disaccharide analysis have shown sulfation ratios at positions C4:C6 of the F2 and F3 fractions respectively as 70:20% and 50:30%, and the balance of non-sulfated and 4,6-di-sulfated units. The preliminary results here suggest that GAG-based extracts from SBW fish heads are suitable alternative products to be used in soft tissue augmentation, although further long-term biocompatibility studies are still required.

Skin regeneration effect of the Glycosaminoglycans from Liparis tessellatus eggs.

A purified Glycosaminoglycans (GAGs) extract from L. tessellatus eggs was enzyme-hydrolyzed and then fractionated with DEAE-Sepharose column chromatography. The fractions were subsequently subjected to skin regeneration effects analysis against skin fibroblast (CCD-986sk) cell lines. Fraction 3 is evidently to have tyrosinase inhibition activity by 20.1% at concentration of 50mg/mL. DOPA oxidation assay, collagenase inhibition activity assay, fibroblast proliferation assay, and production of type I C-peptide assays were done to further proof the skin regeneration effect of GAGs fractions. Results revealed that fraction 3 has effective skin regeneration activities at a concentration of 200mg/mL.

Hyaluronidase-inhibitory activities of glycosaminoglycans from Liparis tessellatus eggs.

Polysaccharide fractions isolated from L. tessellatus eggs were purified and eluted using the DEAE-sepharose fast flow column. These were collected, tested and pooled based on their sugars content: F1, F2, and F3 which contain 26.8, 23.3, and 20.2% sulfated glycans; 34.5, 38.2, and 45.0% uronic acids; and 23.5, 19.0, and 7.5% acetylhexosamines and hexosamines, respectively. Hyaluronidase inhibitory effects of the fractions are in the order F3>F2>F1>Ascorbic acid, with F3 having the highest inhibition among the fractions and that of the standard, ascorbic acid. The electrospray ionization tandem mass spectrometry (ESI-MS/MS) confirmed the presence of uronic acids on F3, which could be a 0,2A2 fragment plus loss of methyl group which is very common among non-methylated, sulfated disaccharides.

Thermoelectric materials by using two-dimensional materials with negative correlation between electrical and thermal conductivity.

In general, in thermoelectric materials the electrical conductivity σ and thermal conductivity κ are related and thus cannot be controlled independently. Previously, to maximize the thermoelectric figure of merit in state-of-the-art materials, differences in relative scaling between σ and κ as dimensions are reduced to approach the nanoscale were utilized. Here we present an approach to thermoelectric materials using tin disulfide, SnS2, nanosheets that demonstrated a negative correlation between σ and κ. In other words, as the thickness of SnS2 decreased, σ increased whereas κ decreased. This approach leads to a thermoelectric figure of merit increase to 0.13 at 300 K, a factor ∼1,000 times greater than previously reported bulk single-crystal SnS2. The Seebeck coefficient obtained for our two-dimensional SnS2 nanosheets was 34.7 mV K(-1) for 16-nm-thick samples at 300 K.

Enzyme-assisted extraction of anticoagulant polysaccharide from Liparis tessellatus eggs.

This study aimed to recover a heparin-like anticoagulant polysaccharide from Liparis tessellatus eggs (PLE) by using enzyme-assisted extraction technique. Extraction experiments were carried out using three different enzymes (Alcalase®2.4 L, Flavourzyme®500 MG, and Protamex®) under different conditions of temperature (45, 50, and 55°C), pH (6.5, 7.0, and 7.5), incubation time (24, 36, and 48 h), and enzyme to substrate ratio (E/S=0.5, 1.0, and 1.5%, w/w), which were combined according to a D-optimal design. Statistical analysis of extraction results allowed identifying the variables with greater influence on the extraction yield, and selecting the conditions that maximize the PLE extraction. The best extraction results were achieved when using the Protamex® enzyme in an E/S ratio of 1.34% (w/w), pH 6.60, 47.40°C, during 26.50 h. Under these conditions, a polysaccharide yield of 2.10% (w/w) was obtained. Clotting time measurements, activated partial thromboplastin time, and prothrombin time for evaluation of the anticoagulant properties of PLE were determined and showed increasing activities in correlation with the concentrations used. In the final step, the heparin-like nature of PLE was confirmed by digestion with heparinases I, II, and III, which showed ΔDiHS-0S, ΔDiHS-6S, ΔDiHS-diS1, and ΔDiHS-diS2 at compositions of 0.04, 0.03, 0.35, and 0.24 mol/g, respectively.

Optical Properties of Cu-Doped ZnO Films Prepared by Cu Solution Coating.

This work demonstrates the fabrication of Cu-doped ZnO films by Cu solution coating method. Cu ink was spin coated on ZnO thin films prepared by e-beam deposition. After curing and annealing at high temperatures, structural, morphological and optical properties of the films were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and spectrofluorometer, respectively. The XRD results showed that ZnO films formed polycrystalline with a hexagonal wurtzite structure, and the grain size increased with increasing the annealing temperature from 500 to 850 °C. The changes in lattice parameters were caused by grain size, strain, and residual stress. Morphological analysis have revealed that the Cu-doped ZnO film after annealing at 500 °C has flat surface with uniformly distributed grain size, which became porous after higher temperature annealing process. Energy dispersive spectroscopy (EDS) and photoluminescence spectras have shown the presence of Zn, Cu, and O elements, and combined violet, blue, green and weak red emissions between 350 and 650 nm in the ZnO films, respectively.

Ascidian tunicate extracts attenuate rheumatoid arthritis in a collagen-induced murine model.

Murine rheumatoid arthritis models are often used to investigate the potential therapeutic effects of candidate drugs. The present study has been conducted in order to investigate the therapeutic efficacy of ascidian tunicate extracts in a collagen-induced arthritis DBA1/J mice model. Four types of formulas, ascidian tunicate extracts (ATE), crude ascidian tunicate glycans (ATEC), ascidian tunicate extracts with licorice extracts (ATEL), and crude ascidian tunicate glycans with licorice extracts (ATECL) were orally administered into DBA/1J mice for 3 weeks and paw edema and thickness were evaluated. Changes in inflammatory proteins and cytokines levels were monitored in hind leg tissues by Western blot and quantitative PCR analysis. The oral administration of ascidian tunicate extracts alleviated paw edema and improved the histological hind leg cartilage status. The extracts also reduced the matrix metalloproteinase-9 (MMP-9) protein and prostaglandin E synthase (PGES) levels. In addition, the extracts-treated groups showed increased interleukin-10 (IL-10) levels compared with the non-treated group. These findings suggest that orally administered ascidian tunicate extracts might have potential therapeutic effects for the treatment of rheumatoid arthritis.

Electrically tunable birefringence of a polymer composite with long-range orientational ordering of liquid crystals.

We report an optical film with electrically tunable birefringence in which the liquid crystals (LCs), mixed with the host polymer, form long-range ordering. The film was prepared through polymerization without phase separation between the LCs and polymers. Driving voltage below 30 V for full switching of birefringence is achieved in a 6 µm-thick film. Electro-optical investigations for the film suggest that the long-range ordering of the LCs mixed in the film caused by polymerization lead to rotations of the LCs as well as optical anisotropy in the film. These films with electrically tunable birefringence could have applications as flexible light modulators and phase retardation films for 2D-3D image switching.

Electroluminescent devices with function of electro-optic shutter.

The polymer-dispersed liquid crystal (PDLC) was used as a dielectric layer of electroluminescent (EL) device to provide multi-function of electroluminescence and electro-optic shutter. A 50 µm-thick PDLC layer was formed between a transparent electrode and a ZnS:Cu phosphor layer. The electro-optic properties of the EL device were not distorted by the introduction of the PDLC layer. The extraction efficiency of luminescence was improved by more than 14% by PDLC layer. The transmittance of the PDLC was also founded not to be degraded significantly by excitation frequency. Therefore, the electroluminescence of the device was ignited by excitation frequency at a given voltage for full transparency of the PDLC. This device has great potential for applications in transparent displays with the function of a privacy window.

Nutraceutical functionalities of polysaccharides from marine invertebrates.

Many researchers are seeking functional materials from marine resources. These marine resources can be used as traditional food additives, and specifically, these are based on polysaccharides. To date, there is a big opportunity to develop new high-value added products with indispensable functional characteristics, which can be used in nutraceuticals either as additives or supplements. Also, a crossover in the pharmaceutical market may be established. Some glycosaminoglycans (GAGs) mimetic-type molecules are already being utilized in the field of nutrition as well as in the cosmetics industry. This chemical is used as a dietary supplement to maintain the structure and function of cartilages, for the relief of pain caused by osteoarthritic joints, and can also be used as an anti-inflammatory agent. Recently, in relation to the prevalence of mad cow disease and avian influenza, the production of GAGs from marine invertebrates offers new market opportunities as compared with that obtained from bovine or avian livestock.

Synthesis and electro-optical properties of carbazole-substituted pyrene derivatives.

Mono and dicarbazole-substituted pyrene derivatives, 9H-carbazol-9-ylpyrene (MCzP) and 1,6-di(9H-carbazol-9-yl)pyrene (DCzP), with dual-purpose function as a blue emitting and charge transporting layer in organic light emitting diodes, were synthesized and characterized. These series of molecules consisted of an electron donating (D) carbazole and an electron accepting (A) pyrene in D-A and D-A-D shapes. Non-doped blue electroluminescent devices with the configurations of ITO (150 nm)/alpha-NPD (30 nm)/DCzP (40 nm)/LiF (1 nm)/Al (150 nm) (D1) and ITO (150 nm)/2-TNATA (15 nm)/alpha-NPD (20 nm)/DCzP (40 nm)/BCP (15 nm)/Alq3 (10 nm)/LiF (1 nm)/Al (120 nm) (D2) were fabricated. D1 and D2 devices showed blue emission at 492 nm and 488 nm, and maximum luminance of 840 and 7560 cd/m2 obtained at 13 V and 15 V, respectively.

The electro-optical behavior of liquid crystal molecules on the surface of SiO2 inorganic thin films.

Inorganic thin films are well known for the liquid crystal alignment layers for LCoS application due to the higher thermal and photochemical stability of inorganic materials. The switching time of liquid crystals is the important factor for the projection application and the faster switching time is required for the high quality display. The switching behavior of liquid crystal molecules on inorganic thin films might be closely related with the surface properties of the inorganic thin films. Therefore the understanding of surface properties of the inorganic thin films is required for the enhancement of the switching time of liquid crystals of LCoS devices. In this work, we prepared the SiO2 inorganic thin films and the electro-optical behavior of liquid crystal molecules on SiO2 thin film was investigated. The sputtering condition of SiO2 thin film was closely related with the thickness and the surface morphology of SiO2 thin film. The switching time of liquid crystals with negative dielectric constant on SiO2 inorganic thin films was dominantly affected by the size of protrusion on the surface of SiO2 thin film and the surface roughness of SiO2 thin film was also related with the switching time of liquid crystals. From these results, it is possible to prepare the SiO2 inorganic thin film suitable for the liquid crystal alignment layer for VAN LC mode.

Enzymatic hydrolysis of recovered protein from frozen small croaker and functional properties of its hydrolysates.

Fish protein isolate were recovered from frozen small croaker using pH shift. The partial enzymatic hydrolysates were fractionated as soluble and insoluble parts. They were dried using the drum dryer and their functional properties were examined. The total nitrogen content of the enzymatic hydrolysates ranged from 12.9% to 13.7%. The degree of hydrolysis of precipitates was 18.2% and 12.2% for croaker hydrolysates treated with Protamex 1.5 MG (Bacilllus protease complex) and Flavourzyme 500 MG (endoproteases and exoproteases, Aspergillus oryzae), respectively. The TCA supernatant, after centrifugation of hydrolysates, contained numerous peptides ranging from 100 to 4000 daltons. The solubility of the supernatants was higher than that of the precipitates at 0% to 3% NaCl and pH 2 to 10. The precipitate of Flavourzyme- and Protamex-treated hydrolysates showed a high emulsion activity index value compared to egg white and bovine plasma protein. In addition, the highest emulsion stability was observed for Protamex-treated precipitate hydrolysates. Emulsion stability of Protamex-treated precipitate hydrolysates was comparable to those of protein additives (egg white, bovine plasma protein, and soy protein concentrate). Water and fat binding capacity of precipitates were higher than those of supernatant. The results indicate that precipitate hydrolysate from undersized croaker can be used in processed muscle foods as a functional and nutritional ingredient.

Chondroitin sulfate extracted from ascidian tunic inhibits phorbol ester-induced expression of Inflammatory factors VCAM-1 and COX-2 by blocking NF-kappaB activation in mouse skin.

Inflammatory factors are known to play a key role in promoting tumorigenesis; therefore, it is a promising strategy to inhibit the inflammation for cancer prevention. The current study was performed to investigate the potential effects of chondroitin sulfate (CS) extracted from ascidian tunic on the expression of inflammatory factors induced by treatment with 12- O-tetradecanoylphorbol-13-acetate (TPA) and to elucidate the underlying molecular mechanism of CS action in mouse skin inflammation. TPA was topically applied to the shaven backs of ICR mice with or without CS (1 or 2 mg) for 4 h. The results demonstrated that CS suppressed TPA-induced edema and reduced the expression of cyclooxygenase-2, vascular cell adhesion molecule-1, and Akt signaling in mouse skin. These studies suggest that CS from ascidian tunic may be developed as an effective natural anti-inflammatory agent.

Chondroitin sulfate extracted from the Styela clava tunic suppresses TNF-alpha-induced expression of inflammatory factors, VCAM-1 and iNOS by blocking Akt/NF-kappaB signal in JB6 cells.

Inflammatory mediators are known to play a key role in tumorigenesis, therefore, it is a promising strategy to inhibit the inflammation for cancer prevention and/or treatment. Current study was performed to investigate the effects of chondroitin sulfate (CS) extracted from Styela clava tunic on TNF-alpha-induced inflammation and to elucidate the mechanism of CS on the regulation of inflammatory factors in JB6 cells. Our results showed that CS inhibited TNF-alpha-induced NF-kappaB activation and subsequent vascular cell adhesion molecule 1 and inducible nitric oxide synthase expressions by blocking Akt signals in JB6 cells. Our results suggest that CS may be developed as an effective anti-inflammatory agent in the future.