The objective of this study was to develop the capabilities to determine the effect of operational parameters on the morphology of powders produced by spray drying. A device used for monitoring morphological characteristics of a single suspended droplet was constructed. It allowed for monitoring and recording the images of a drying droplet as a function of time. The experimental drying was carried out for a number of systems that highlighted the effects of different controlling parameters, such as drying temperature and initial solute concentration. The experiments demonstrated that the shell structure of a drying droplet played an important role in determining the final dried particle morphology. In addition, the shell structure of a drying droplet varies from material to material, which increases the difficulty in the modeling prediction. Several materials with different physical properties, such as solubility and latent heat of crystallization, were investigated. Two sets of experiments, Ca(C 2 H 3 O 2 ) 2 versus NaC 2 H 3 O 2 and K 2 CO 3 versus Na 2 CO 3 , were run to examine the effect of material solubility. The effect of latent heat of crystallization was examined by experiment with NH 4 Cl versus NaCl.In summary, low drying temperature and material with high latent heat of crystallization (i.e., endothermic crystallization) were favorable for small, dense, and regularly-shaped particles. Materials that formed an elastic shell structure such as ammonium chloride led to hollow particle formation. Material with high solubility led to small, dense, irregularly-shaped particles. A higher initial solute concentration was favorable for the formation of a large dense particle.

The aluminum-doped ZnO (AZO) nanostructures with different Al concentrations were synthesized on AZO/glass substrate via a simple hydrothermal growth method at a temperature as low as 85 degrees C. The morphologies, crystallinity, optical emission properties, and chemical bonding states of AZO nanostructures show evident dependence on the aluminum dosage. The morphologies of AZO nanostructures were changed from vertically aligned nanowires (NWs), and NWs coexisted with nanosheets (NSs), to complete NSs in respect of the Al-dosages of 0-3 at.%, 5 at.%, and 7 at.%, correspondingly. The undoped ZnO and lightly Al-doped AZO (< or = 3 at.%) NWs are single-crystalline wurtzite structure. In contrast, heavily Al-doped AZO sample is polycrystalline. The AZO nanostructure with 3 at.% Al-dosages reveals the optimal crystallinity and less structural defects, reflecting the longest carrier lifetime and highest conductivity. Consequently, the field-emission characteristics of such an AZO emitter can exhibit the higher current density, larger field-enhancement factor (beta) of 3131, lower turn-on field of 2.17 V/microm, and lower threshold field of 3.43 V/microm.

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This paper presents the design of a low-cost programmable controller integrated circuit (IC) for general power electronics applications. The architecture of the programmable controller IC consists of 10-bit ADC and DAC, programmable counter array (PCA), which is configured to function as PWM, and a control unit (processor) for regulation. The processor unit is configured as digital compensator, through fewer program steps to perform accurate compensation on the voltage control loop of the converter system. Limit-cycle oscillation is minimized through inclusion of a sufficiently low integral gain term in the control law. A hybrid control method is first used to control the input voltage and current waveforms to achieve a unity power factor correction. It is observed that the programmable converter achieves the high efficiency power conversion. The conversion efficiency of the digital controlled boost converter is 91% with a 0.8 % ripple voltage performance. While in power factor correction (PFC) circuit application, the power factor and output ripple voltage of converter are 0.995 and 0.93%, respectively. The chip is implemented with TSMC 0.25 um CMOS process.

Background/purpose: In this study, we evaluated the effectiveness of oral uracil etegafur (UFUR) as a postoperative adjuvant treatment for patients with advanced oral squamous cell carcinoma (OSCC). Materials and methods: The study cohort consisted 80 patients with advance cancer treated between January 2003 and December 2007. Half of the patients received oral UFUR as postoperative metronomic adjuvant chemotherapy, while the other half received no treatment. No patients received postoperative radiotherapy or other systemic chemotherapy. Disease-free survival and toxicity were evaluated in these two groups. Twenty-two patients were assessed pre-and postoperatively for viable circulating endothelial progenitor cells using flow cytometry. Results: The disease-free survival rates at 4 years were 84.6% with oral UFUR treatment and 60.9% without UFUR therapy (P Z 0.02). The toxicity and disease progression profiles did not differ significantly between the two groups, but viable circulating endothelial progenitor cell counts decreased after the administration of oral UFUR. Advanced OSCC patients who received oral UFUR had a better prognosis than those who did not. Conclusion: Oral UFUR is a promising postoperative metronomic adjuvant chemotherapy regimen for advanced OSCC.Please cite this article in press as: Lin J-S, et al., Oral uracil and tegafur as postoperative adjuvant metronomic chemotherapy in patients with advanced oral squamous cell carcinoma, Journal of Dental Sciences (2015), http://dx.