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Glass-ceramic materials exhibit versatile properties which may be utilized in various unique ways, especially in biomedical applications. The first bioactive glass manufactured, 45S5, was used to promote the repair and regeneration of damaged bones. However, the process of melt quench synthesis in the manufacture of 45S5 caused the chemical reactivity to weaken and reduced the porosity. In this study, nanoscale bioactive glass with added Ca and P ions and mesoporous structures was developed by the sol-gel method. It was established that the microstructures of the bioactive glasses proposed in this study had a particle size of about several hundred nm. The phase structures and chemical compositions were determined to demonstrate the feasibility for biomimetic mineral deposition after soaking in simulated body fluid solution. Lastly, the Brunauer-Emmett-Teller nitrogen adsorption-desorption isotherm patterns showed the hysteresis loop for confirming the mesoporous structures. This study presents the process of manufacture of nanoscale bioactive glass and examines its potential utility which would fuel subsequent research in this area.

Many liposomal drug carriers have shown great promise in the clinic. To ensure the efficient preclinical development of drug-loaded liposomes, the drug retention and circulation properties of these systems should be characterized. Iron oxide (Fe3O4) magnetic nanoparticles (MNPs) are used as T2 contrast agents in magnetic resonance imaging (MRI). Gold nanoclusters (GNCs) contain tens of atoms with subnanometer dimensions; they have very low cytotoxicity and possess superb red emitting fluorescent properties, which prevents in vivo background autofluorescence. The aim of this study was to develop dual imaging, nanocomposite, multifunctional liposome drug carriers (Fe3O4-GNCs) comprising MNPs of iron oxide and GNCs. First, MNPs of iron oxide were synthesized by co-precipitation. The MNP surfaces were modified with amine groups using 3-aminopropyltriethoxysilane (APTES). Second, GNCs were synthesized by reducing HAuCl4·3H2O with NaBH4 in the presence of lipoic acid (as a stabilizer and nanosynthetic template). The GNCs were grown by adsorption onto particles to control the size and stability of the resultant colloids. Subsequently, dual Fe3O4-GNCs imaging probes were fabricated by conjugating the iron oxide MNPs with the GNCs via amide bonds. Finally, liposome nanocarriers were used to enclose the Fe3O4-GNCs in an inner phase (liposome@Fe3O4-GNCs) by reverse phase evaporation. These nanocarriers were characterized by dynamic light scattering (DLS), fluorescence spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared (FT-IR) spectrophotometry, superconducting quantum interference device (SQUID), nuclear magnetic resonance (NMR) imaging and in vivo imaging systems (IVIS). These multifunctional liposomal drug delivery systems with dual probes are expected to prove useful in preclinical trials for cancer diagnosis and therapy.

This work develops a dual-function thermosensitive hydrogel to prevent overheating, a side effect of focused ultrasound therapy. The proposed hydrogel has the components of chitosan, β-glycerophosphate, and glycerol. Its thermosensitive sol-to-gel transition gives an instant signal of overheating without the need of any awkward sensing device. Impacts of varying component concentrations on the sol-to-gel temperature, rate, and degree of transparency are also investigated. Chemical structures and ultrasonic coefficients after heating are obtained with a Fourier transform infrared spectroscopy and ultrasonic measurement, respectively. Optimized formula of the proposed hydrogel is 0.5% chitosan, 5% β-glycerophosphate, and 25% glycerol. This hydrogel has a high acoustic impedance (Z=1.8 Mrayl) close to that of human skin, high ultrasonic transmission (T=99%, which is normalized to water) from 25 to 55°C, and low attenuation coefficient (α=4.0Np/m). These properties assure the success of dual functions of the hydrogel developed in this work.

A new type of energy-saving glass, Ag inlaid with SiO 2 nano-structures (Inlay SiO 2 ), is numerically developed here to offer modern buildings a passive but promising way of saving power under sunlight. The profile of glass is identified after optimizing optical responses using the genetic algorithm and a fitness function. Wavelength-selective reflectance ( R ) and transmittance ( T ) are demonstrated with validated programs based on the rigorous coupled-wave analysis algorithm. The high T and low R in the visible range not only saves energy for lighting but diminishes reflected and stray light. The low T and high R in the near-infrared reduce the cost for air-conditioning. Besides the cost can be further reduced, the superiority of this glass over current commercially available products includes the material commonness, light weight, and freedom from adhesion as well as oxidation. The fabrication tolerance of each dimension is further investigated to determine the key one. Other structure configurations are also approached to explore possibilities of alternates.

Chitosan has excellent biodegradable, biocompatible and bio-absorbable properties and has been found increasing use in the biomedical field in recent decades. The linear birefringence (LB), linear diattenuation (LD), circular birefringence (CB), circular diattenuation (CD), and depolarization properties of chitosan hydrogel films crosslinked in citrate acid buffer solution (CBS) are extracted using an analytical Mueller matrix method. It is shown that the optical phase retardance property of the hydrogel films provides a reliable indication of both the chitosan concentration of the film and the pH value of the CBS crosslinking environment. In addition, chitosan hydrogel suspension with low-concentration crosslinked in CBS environments with various pH values are studied by the speckle contrast of the projected images obtained when illuminating the suspension with a scanned laser pico-projector (SLPP). It is found that for the samples crosslinked in an acidic environment, the speckle contrast decreases with an increasing pH value. By contrast, for the samples crosslinked in an alkaline CBS environment, the speckle contrast increases as the pH value increases. It is concluded that both the phase retardance and the speckle contrast enable the pH value of the CBS crosslinking solution to be reliably determined. However, of the two methods, the SLPP method yields improved measurement sensitivity. Overall, the results presented in this study show that the analytical Mueller matrix method and SLPP method provide an effective means of characterizing the optical properties, concentration and crosslinking environment of chitosan hydrogel films and suspensions.

The images projected by scanned laser pico-projectors (SLPPs) contain speckle noise caused by the reflection of the high coherent laser light source from the projection screen. The speckle contrast varies in accordance with the volume roughness of the screen and can be applied for relative two-dimensional (2-D) nanoparticle concentration measurement in both solid and liquid solutions. The great advantage in this study is that it can measure several samples simultaneously. The experimental results show that the green laser within the SLPP provides a better measurement sensitivity and resolution than the red or blue lasers. In solid solution measurement, different concentrations of nanoparticles embedded in a poly (methyl methacrylate) (PMMA) matrix are tested and the maximum sensitivity and resolution are found to be −8.59 ((speckle contrast %)/(wt%)) and 0.013 (wt%), respectively. In liquid solution measurement, different concentrations of nanoparticles dissolved in deionized water are also tested and the maximum sensitivity and resolution of green laser in SLPP are found to be −2050 ((speckle contrast %)/(molar concentration (M)) and 7.51 × 10−5 M, respectively. Finally, the system shows ability to measure the collagen concentrations from 0.125 to 0.025%. Accordingly, the proposed system provides a viable, low-cost solution for high-sensitivity in biomedical, chemical and environmental applications.

The natural frequency of the flapwise bending vibration, and coupled lagwise bending and axial vibration is investigated for the rotating beam. A method based on the power series solution is proposed to solve the natural frequency of very slender rotating beam at high angular velocity. The rotating beam is subdivided into several equal segments. The governing equations of each segment are solved by a power series. Numerical examples are studied to demonstrate the accuracy and efficiency of the proposed method. The effect of Coriolis force, angular velocity, and slenderness ratio on the natural frequency of rotating beams is investigated.

Chitosan is widely recognized as a natural and proper scaffold material; however, as a base substrate, it shows little promotion effect for the growth of cultured fibroblast cells. In this study, chitosan in a film form was prepared and used as a cell-culturing matrix, followed by patterning the evaporated Au upon it. Micro-scale Au clusters of ≈ 150 μm in diameter and ≈ 20 nm in thickness were then patterned and adhered upon the chitosan matrix. Physical and chemical properties of Au/chitosan were characterized. In particular, nano-indentation with dynamic contact module was applied to measure the nano-hardness of the tailored surfaces on Au/chitosan. Fibroblast cells were thereafter cultured on Au/chitosan. Experimental results demonstrated that as compared with the chitosan matrix, Au clusters and their boundary area exhibited favorable to promote cell adhesion, spreading, and growth. As well, nano-hardness on the boundary area of Au/chitosan significantly enhanced, while the cultured fibroblast cells aggregated upon Au clusters and the boundary area. In combination with the possible chemical and mechanical changes resulted by the evaporation of Au clusters upon the chitosan matrix, a selectively-enhanced Au/chitosan to promote fibroblast cells proliferation was created. Such design is anticipated for enabling a surface for scaffold materials with the cell-guidable function.

This study examined the psychometric properties of the Chinese version of the Fagerstrom Test for Nicotine Dependence (FTND). Criterion validity, factorial structure, and construct reliability were conducted using PRELIS 2 and LISREL 8.7 software. Two hundred and forty-five adult smokers were recruited from April to August 2005 in Taiwan. Because some items of the FTND are dichotomous and ordinal, biserial and polyserial correlations between the items and saliva cotinine levels were utilized. Confirmatory factor analyses (CFA) were performed to compare the relative fit of three competing models. Computation of the construct reliability was necessitated by a lack of tau-equivalence. The results demonstrated that the Chinese version has satisfactory validity and reliability. One item, "Smoke more in the morning," had low correlations with saliva cotinine. CFA found the items of the Chinese version were best modeled as two correlated factors without a cross-loading. These findings differ from the previous research testing the English version. Studies addressing the specific features of cigarette dependence in different socio-cultural contexts are needed.