Self-assembly of polyelectrolytic multilayer thin films of polyelectrolytes on quartz crystal microbalance for detecting low humidity

Low-humidity sensors were made by layer-by-layer (LBL) self-assembly of poly(4-styrenesulfonic acid-co-maleic acid) (PSSMA) or poly(styrenesulfonic acid) sodium salt (PSS) and poly(allylamine hydrochloride) (PAH) into multilayer thin films on a gold electrode of quartz crystal microbalance (QCM). The thin films were characterized by QCM and atomic force microscopy (AFM). The effects of maleic acid (MA) in PSSMA, the number of layers and the ionic strength on the low-humidity sensing properties (sensitivity) were compared with those of PSS. The sensitivity of the PSSMA/PAH multilayer thin film exceeded that of the PSS/PAH multilayer thin film when the multilayered thin films of polyelectrolytes were prepared from solutions without NaCl. The sensitivity of both PSSMA/PAH and PSS/PAH multilayered thin films was increased by increasing the number of layers and by adding salt to the deposition solution. The PSS/PAH multilayered thin film that was prepared from the solutions with NaCl had the highest sensitivity (1.923 −ΔHz/Δppm_v at 27.5 ppm_v) and a short response time. Spin-coating was also adopted to fabricate PSS-based low-humidity sensors for comparison.     

A 155.52 mbps-3.125 gbps continuous-rate clock and data recovery circuit

A 155.52 Mbps-3.125 Gbps continuous-rate clock and data recovery (CDR) circuit using the full-rate bang-bang phase detector is presented. A frequency detector is proposed to eliminate the harmonic locking problem even with a wide range of data rates and its theoretical analysis is also discussed. A quadrature divider is also presented to generate the clocks with accurate quadrature phases. This CDR circuit has been realized in a 0.18-/spl mu/m CMOS process and its die area is 1.1/spl times/0.8 mm/sup 2/. It consumes 95 mW at the highest bit rate of 3.125 Gbps. It can recover the NRZ data of a 2/sup 31/-1 PRBS with the bit rate ranging from 155.52 Mbps to 3.125Gbps for the incremental frequency acquisition and the NRZ data of a 2/sup 7/-1 PRBS for the decremental frequency acquisition. All the measured bit error rates are less than 10/sup -12/.     

Novel rapid switching and bleaching electrochromic polyimides containing triarylamine with 2-phenyl-2-isopropyl groups

A series of novel organosoluble polyimides and copolyimides with a propeller-shaped triarylamine unit were prepared from diamine and various aromatic dianhydrides via direct polycondensation. All of the polymers possessed tough, flexible, and strong films with high molecular weights. The polyimide and copolyimide films revealed electrochromic characteristics, with a color change from pale yellowish at its neutral state, to green, and finally to blue at its oxidized state, at applied potentials ranging from 0 to 1.50 V. The polyimide (Ib) film exhibited switching times of 4.5 s at 1.08 V at 424 and 877 nm and 1.9 s for fast bleaching due to a pendent substituted 2-phenyl-2-isopropyl group. Cyclic voltammetry (CV) of the polymer films showed two reversible redox couples at potentials of 0.91-0.99 V and 1.30-1.38 V, respectively. The CV results of the model compound M1 and model polyimide M2, were not a match to the oxidation peaks of polyimide Ib, indicating that the contribution of the oxidation was not only from the electron removal of nitrogen atoms.     

Growth of carbon nanotubes on cobalt catalyst film using electron cyclotron resonance chemical vapour deposition without thermal heating

This paper demonstrates that carbon nanotubes (CNTs) can be synthesized on a cobalt coated silicon substrate using electron cyclotron chemical vapour deposition and without intentionally heating the substrate. With the mixed gases of C(3)H(8)/N(2), CNTs with a multi-walled structure and a diameter up to 70?nm have been observed. Results show that the diameter of the CNTs increases with the thickness of the cobalt catalyst film and the amount of nitrogen incorporated in the CNT films considerably influences the structures of the CNTs. Vertically aligned CNTs can be fabricated with a microwave power as low as 300?W and the flow rate ratio of C(3)H(8)/N(2) = 20/20?sccm. The CNTs exhibit a turn-on field of 0.2?V?μm(-1) determined at the emission current density of 10?μA?cm(-2).     

Antinociceptive and Anti-Inflammatory Effects of Zerumbone against Mono-Iodoacetate-Induced Arthritis

The fresh rhizome of Zingiber zerumbet Smith (Zingiberaceae) is used as a food flavoring and also serves as a folk medicine as an antipyretic and for analgesics in Taiwan. Zerumbone, a monocyclic sesquiterpene was isolated from the rhizome of Z. zerumbet and is the major active compound. In this study, the anti-inflammatory and antinociceptive effects of zerumbone on arthritis were explored using in vitro and in vivo models. Results showed that zerumbone inhibited inducible nitric oxide (NO) synthase (iNOS), cyclooxygenase (COX)-2 expressions, and NO and prostaglandin E₂ (PGE₂) production, but induced heme oxygenase (HO)-1 expression in a dose-dependent manner in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. When zerumbone was co-treated with an HO-1 inhibitor (tin protoporphyrin (SnPP)), the NO inhibitory effects of zerumbone were recovered. The above results suggest that zerumbone inhibited iNOS and COX-2 through induction of the HO-1 pathway. Moreover, matrix metalloproteinase (MMP)-13 and COX-2 expressions of interleukin (IL)-1β-stimulated primary rat chondrocytes were inhibited by zerumbone. In an in vivo assay, an acetic acid-induced writhing response in mice was significantly reduced by treatment with zerumbone. Furthermore, zerumbone reduced paw edema and the pain response in a mono-iodoacetate (MIA)-induced rat osteoarthritis model. Therefore, we suggest that zerumbone possesses anti-inflammatory and antinociceptive effects which indicate zerumbone could be a potential candidate for osteoarthritis treatment.     

A 200-Mbps/spl sim/2-Gbps continuous-rate clock-and-data-recovery circuit

A 200-Mbps/spl sim/2-Gbps continuous-rate clock-and-data-recovery (CDR) circuit using half-rate clocking is presented. To detect the data with wide-range bit rates, a frequency tracing circuit (FTC) is used to aid the frequency acquisition. A wide-range and low gain voltage-controlled oscillator (VCO) is also presented by using analog and digital controlled mechanisms. A two-level bang-bang phase detector is utilized to improve the jitter performance and speed up the locking process. This CDR circuit has been realized in a 2P4M 0.35-/spl mu/m CMOS process. The experimental results show that this CDR circuit with the proposed FTC can receive 2/sup 31/-1 pseudorandom bit stream when the bit rate ranges from 200 Mbps to 2 Gbps without the harmonic-locking issue. All measured bit error rates are below 10/sup -12/. The measured root-mean-square and peak-to-peak jitters are 5.86 ps and 41.8 ps, respectively, at 2 Gbps.     

Therapeutic Effect of Platelet-Rich Plasma Improves Bladder Overactivity in the Pathogenesis of Ketamine-Induced Ulcerative Cystitis in a Rat Model

The present study attempted to elucidate whether intravesical instillation of platelet-rich plasma (PRP) could decrease bladder inflammation and ameliorate bladder hyperactivity in ketamine ulcerative cystitis (KIC) rat model. Female Sprague Dawley (S-D) rats were randomly divided into control group, ketamine-treated group, ketamine with PRP treated group, and ketamine with platelet-poor plasma (PPP) treated group. Cystometry and micturition frequency/volume studies were performed to investigate bladder function. The morphological change of bladder was investigated by Mason’s trichrome staining. Western blotting analysis were carried out to examine the protein expressions of inflammation, urothelial differentiation, proliferation, urothelial barrier function, angiogenesis and neurogenesis related proteins. The results revealed that treatment with ketamine significantly deteriorated bladder capacity, decreased voiding function and enhanced bladder overactivity. These pathological damage and interstitial fibrosis may via NF-κB/COX-2 signaling pathways and muscarinic receptor overexpression. PRP treatment decreased inflammatory fibrotic biosynthesis, attenuated oxidative stress, promoted urothelial cell regeneration, and enhanced angiogenesis and neurogenesis, thereafter recovered bladder dysfunction and ameliorate the bladder hyperactivity in KIC rat model. These findings suggested that the PRP therapy may offer new treatment options for those clinical KIC patients.