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Abalone nacre is a natural ceramic-based composite consisting of 95 wt.% stacked CaCO3 tiles and 5 wt.% organic layers organized into a unique multilayer structure, which leads to exceptional fracture toughness. Multi-scale toughening mechanisms such as crack deflection at the organic/inorganic interfaces, viscoelastic organic glue, nano-asperities and interconnected mineral bridges between tiles, collaborate synergistically to prevent deformation and failure. Inspired from abalone nacre, multilayer coatings of zirconia and polyimide layers were synthesized by a hybrid PVD system combining sputtering and pulsed laser deposition. By introducing thin polyimide interlayers between zirconia layers, the fracture toughness of multilayer coatings (5.2 MPa·m1/2) was significantly enhanced, approaching six times higher than that of zirconia monolayer (1.0 MPa·m1/2). The thickness ratio of zirconia and polyimide was kept 10:1 while thickness and number of interfaces were altered to investigate the effect of organic/inorganic interfaces on the mechanical properties of the coatings. Results showed that multilayer structure could enhance the fracture toughness of coatings. Fracture toughness significantly increased with increasing number of interfaces yet the hardness slightly decreased. SEM observation verified that the major toughening mechanism of bio-inspired multilayer coatings was crack deflection at organic/inorganic interfaces, which prevented crack from direct propagation. With certain critical interfacial roughness, fracture toughness of multilayer can be further improved, similar to the function of nano-asperities in abalone nacre. Bio-inspired organic/inorganic multilayers could improve the toughness of intrinsically brittle ceramic or glass coatings and extend their applications in protection, wear and corrosion resistance, optical and biomedical fields.

A quad-band GSM/GPRS/EDGE cellular system, implemented in 65-nm CMOS, is integrated in a multimedia SoC with BT and FM. A low-IF receiver with digital IRR tracking is selected for its smaller area and better noise figure. The receiver achieves a sensitivity of $-$ 110 dBm, an IIP3 of $-$ 9.5 dBm, and a calibrated image rejection ratio of 65 dBc, while consuming 61 mA. The polar transmitter architecture is chosen for its SAW-less TX capability, smaller area, and low current consumption. It achieves an ORFS (output radio frequency spectrum) of $-$ 68 dB and $-$ 64 dB at 400 kHz in GMSK and EDGE mode, respectively, while consuming 61 mA. The loop gain normalization, dc offset and AM/PM delay of the polar system are compensated to be better than 1% error, 1 mV, and 1.9 ns within 170 $\mu$ s, respectively. Several techniques are employed to minimize interference coupling within the SoC; these include frequency planning, circuit implementation, transceiver architecture optimization, and digital clock selection. The measured sensitivity and the output spectrum of the three wireless systems under full-feature phone operation are virtually unchanged.

The Alexandrite laser, which has a wavelength of 755 nm, has recently been used in dermatologic and esthetic surgery. This laser was introduced to treat pigmented lesions and aid in laser hair removal. It is so used because it provides deep penetration beneficial in treating pigmented lesions such a

Novel miniature parallel-coupled bandpass filters are proposed, by using additional lumped capacitors to reduce the lengths of coupled-line sections. With the lumped-element K-inverters at the input/output and between coupled-line sections, the proposed filter may be equivalent to the quarter-wavelength resonator filter such that no repeated passband at twice the center frequency is observed. In addition, by introducing the capacitive cross-coupling effect, two transmission zeros can be achieved. The locations of the transmission zeros may be simply adjusted by varying the cross-coupling capacitance. Simple equivalent-circuit models along with design formulas are also established, from which the proposed parallel-coupled bandpass filters based on lumped-distributed coupled-line sections may be designed and investigated. Specifically, a miniature 4th-order microstrip bandpass filter with good selectivity and stopband rejection is implemented and carefully examined.

In this paper, we propose a method to vectorize Chinese characters in calligraphy documents. Our system can prevent the zigzag phenomena when the characters are enlarged. The system contains two modules: contour segment extraction and description. In the former, high curvature points on contours are detected as corner points, which divide the contour into several segments. In the latter, a contour segment can be described either by a straight line or a cubic Bezier curve. According to relations between the contour segment and the Bezier curve, control points are adjusted to fit the contour segment better. When the curve fitness cost is small enough, the shape is described well. The processing time of our curve fitting is about five seconds per A4 image, which has 4488 contour segments. Experimental results demonstrate that our system is efficient and promising.

The consistent association of elevated antibody titers to the Epstein-Barr virus associated antigens in patients with nasopharyngeal carcinoma has led to correlations of antibody titers with tumor presence and extent. Recently, serum levels of specific glycoproteins and immunoglobulins have been correlated with tumor presence and extent in patients with head and neck squamous carcinomas, and elevation of the immunoglobulin IgA has been described in patients with nasopharyngeal carcinoma. These correlations prompted a study of 69 untreated patients with nasopharyngeal carcinoma and 53 healthy normal subjects in Taiwan to determine the relations among specific proteins (haptoglobin, α1-acid glycoprotein, α1-antitrypsin, α2-HS-glycoprotein, prealbumin, and albumin), immunoglobulin levels (IgA, IgG, IgM), anti-EBV associated antibody titers, and clinical tumor stage. Elevated antibody titers to EBV-associated antigens (EBV-associated nuclear antigen, viral capsid antigen, and early antigen) were related to tumor presence but not significantly related to clinical tumor stage. Compared with the levels in normal subjects, serum levels of acute-phase proteins (haptoglobin, α1-acid glycoprotein, α1-antitrypsin) were significantly increased (p < 0.001) in patients with nasopharyngeal carcinoma, and levels of α2HS-glycoprotein were significantly decreased (p < 0.001). Uniquely, serum levels of acute-phase proteins, particularly haptoglobin, were directly related to clinical tumor stage (p < 0.05 − 0.001). Furthermore, serum haptoglobin levels correlated directly with anti-EBNA antibody titers (p < 0.03) and serum levels of IgA (p < 0.01). Serum levels of α2HS-glycoprotein correlated inversely with titers of IgA antibodies to early antigen (p < 0.03). The findings demonstrate that measurement of specific serum glycoprotein and immunoglobulin levels may be useful adjuncts to anti-EBV antibody titers in the serodiagnosis and monitoring of response to treatment of nasopharyngeal carcinoma and aid in the derivation of improved staging systems for these tumors.

Sera from 126 patients with nasopharyngeal carcinoma (NPC), 48 other cancers (OC) and 54 normal controls (NC) were collected at the National Taiwan University Hospital and tested for immunoglobulin levels as well as for IgG and IgA antibodies against Epstein-Barr virus (EBV) capsid antigen (VCA), early antigen (EA) and nuclear antigen (EBNA) by the immunofluorescence antibody technique. The mean concentrations of IgA and IgG in untreated NPC patients were higher than those of OC and NC groups, but IgM level was lower than that of OC group. The incidence and geometric mean titers (GMT) of anti-EA and anti-VCA in serum IgG and IgA, and anti-EBNA were substantially higher in NPC patients than in OC and NC groups. The GMT of anti-VCA in IgG and IgA, and anti-EA in IgG increased with advancing clinical stages of NPC but no such an increment was observed in anti-EBNA. After successful treatment the GMT of anti-VCA in IgG and IgA, anti-EA in IgG, and anti-EBNA became lower than those of pre-treatment and these antibody titers except anti-EBNA titers increased again in recurrent cases, indicating that tests for EBV-associated antibody titers are useful for monitoring the clinical status of NPC. In untreated and treated NPC patients, anti-VCA in IgG and IgA were significantly correlated (correlation coefficient r = 0.65 and 0.72 respectively, i.e. p < 0.005 in both groups). A correlation was also observed in anti-EA in IgG and IgA in untreated NPC patients (r = 0.2, p < 0.05). Among 11 throat washings of untreated NPC patients tested, anti-EA and anti-VCA in both IgG and IgA were detected in 1, 5, 1 and 2 cases, respectively.