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Chondrosarcoma is a malignant bone tumor that emerges from abnormalities in cartilaginous tissue and is related with lung metastases. Nicotinamide phosphoribosyltransferase (NAMPT) is an adipocytokine reported to enhance tumor metastasis. Our results from clinical samples and the Gene Expression Omnibus data set reveal that NAMPT levels are markedly higher in chondrosarcoma patients than in normal individuals. NAMPT stimulation significantly increased lysyl oxidase (LOX) production in chondrosarcoma cells. Additionally, NAMPT increased LOX‐dependent cell migration and invasion in chondrosarcoma by suppressing miR‐26b‐5p generation through the c‐Src and Akt signaling pathways. Overexpression of NAMPT promoted chondrosarcoma metastasis to the lung in vivo. Furthermore, knockdown of LOX counteracted NAMPT‐facilitated metastasis. Thus, the NAMPT/LOX axis presents a novel target for treating the metastasis of chondrosarcoma. [ABSTRACT FROM AUTHOR]

A wideband single chip inductor-loaded coplanar waveguide (CPW)-fed inductive slot antenna is proposed and experimentally studied in this paper. In order to have bandwidth broadened and dimensions controlled as well, an inductor with optimal value is shunt at one far end of the inductive slot antenna to help excite an additional lower resonance point. Moreover, the bandwidth is further widened by enlarging the over-the-slot ground height. With both the optimal chip inductor and ground height values, a 10 dB return loss bandwidth of (34.5%, 1756 MHz) centered at 5083 MHz is achieved, which is, in percentage, 3.7 times the (9.3%, 531 MHz) bandwidth of the 5666 MHz stand-alone CPW-fed inductive slot antenna. Index Terms--Antenna, coplanar waveguide (CPW)-fed, inductive slot antenna, inductor-loaded, wideband operation.

A dual-band coplanar waveguide (CPW)-fed hybrid antenna consisting of a 5.4 GHz high-band CPW-fed inductive slot antenna and a 2.4 GHz low-band bifurcated F-shaped monopole antenna is proposed and investigated experimentally. This antenna possesses an appealing characteristic that the CPW-fed inductive slot antenna reinforces and thus improves the radiation efficiency of the bifurcated monopole antenna. Moreover, due to field orthogonality, one band resonant frequency and return loss bandwidth of the proposed hybrid antenna allows almost independent optimbation without noticeably affecting those of the other band. Index Terms--Antenna, coplanar waveguide (CPW)-fed, dual-band, inductive slot antenna, monopole antenna, orthogonal polarizations.

A new fast-response current-mode buck converter with improved $I^{2}$ -controlled techniques is presented in this paper. First, the proposed converter uses the improved $I^{2}$ -controlled techniques to design a new current-mode buck converter. The current-sensing circuit can fully sense the inductor current. The sensing current is divided into two paths; one is flown through the dynamic-acceleration circuit, and the other is transferred to hysteretic comparator to compare with dynamic-acceleration output. The $I^{2}$ -controlled techniques increase the bandwidth of the converter’s closed-loop gain that will speed up the converter’s transient response. Second, the converter uses the phase–frequency-controlled techniques to lock the switching frequency of the adaptive on-time generator of the proposed converter and reduce the difficulty of the output filter. Third, the circuit does not need slope compensation, so that it is very simple to implement. Fourth, the proposed buck converter was implemented with TSMC 0.35- $\mu \text{m}$ CMOS 2P4M processes, which is a low-cost process. The experimental results show that the maximum load current can be up to 600 mA, the input voltage range is 2.6–4 V, the output voltage is regulated at 1.8 V, the maximum power efficiency is up to 90%, and the transient response times are 2.5 and $2.8~\mu \text{s}$ at rising and falling edges, respectively. [ABSTRACT FROM AUTHOR]

A sub-1-μs ultrafast-response buck converter utilizing improved analog-voltage-dynamic-estimation (AVDE) techniques is proposed in this letter to improve previous works. First, the improved AVDE controller uses a new pseudocurrent circuit and a new ramp generator to get low gain, wide bandwidth, wide dynamic range, and low equivalent series resistor $(R_{{\text{ESR}}})$. Second, the proposed converter has high performance, fast transient response, and low output voltage ripple. Third, the circuit does not need slope compensation so that it is very simple to implement. The switching frequency of the proposed buck converter is 1 MHz for nominal 3.3-V input and 0.8–2.5-V output range application. The experimental results prove that the proposed scheme improves the transient response within 1.2 μs and its maximum power efficiency can be up to 91.9%. The fastest transient time of the proposed converter is only 0.8 μs as the switching frequency is equal to 1 MHz. The settling time of the proposed converter is only within 0.8 cycle of the switching frequency. The maximum load current is 300 mA. The proposed buck converter has been fabricated with a commercial 0.35-μm CMOS 2P4M process, and the total chip area is about {1.46 \;\text{mm}\times 1.5} mm, including PADs. [ABSTRACT FROM PUBLISHER]

The omnipotent Li–ion battery charger with multimode control and polarity reversible techniques is presented in this article. The proposed chip is fabricated with TSMC 0.35μm 2P4M complementary metal-oxide- semiconductor processes, and the chip area including pads is 1.5 × 1.5 mm2. The structure of the omnipotent charger combines three charging modes and polarity reversible techniques, which adapt to any Li–ion batteries. The three reversible Li–ion battery charging modes, including trickle-current charging, large-current charging and constant-voltage charging, can charge in matching polarities or opposite polarities. The proposed circuit has a maximum charging current of 300 mA and the input voltage of the proposed circuit is set to 4.5 V. The maximum efficiency of the proposed charger is about 91% and its average efficiency is 74.8%. The omnipotent charger can precisely provide the charging current to the battery. [ABSTRACT FROM PUBLISHER]

SUMMARY A new fast-response buck converter using accelerated pulse-width-modulation techniques is proposed in this article. The benefits of the accelerated pulse-width-modulation technique is fast-transient response, simple-compensation design, and no requirement for slope compensation; furthermore, some power management problems are minimized, such as EMI (Electro Magnetic Interference), size, design complexity, and cost. The traditional voltage-mode speed is slower with the transient response, so an accelerated pulse-width-modulation technique is used to solve the problem of slowed transient response in this article. The proposed buck converter has excellent conversion efficiency with a wide load conditions. The proposed buck converter has been fabricated with TSMC 0.35 µm CMOS 2P4M processes, and the total chip area is 1.32 × 1.22 mm2. Maximum output current is 300 mA when the output voltage equals 1.8 V. When the supply voltage is 3.6 V, the output voltage can be 1-2.6 V. Maximum transient response is less than 5 µs. The simulation and experimental results are presented in this article. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]