Dispersion of Long and Isolated Single-Wall Carbon Nanotubes by Using a Hydrodynamic Cavitation Method.

Single-wall carbon nanotubes (SWCNTs) are promising materials for electronic applications, such as transparent electrodes and thin-film transistors. However, the dispersion of isolated SWCNTs into solvents remains an important issue for their practical applications. SWCNTs are commonly dispersed in solvents via ultrasonication. However, ultrasonication damages SWCNTs, forming defects and cutting them into short pieces, which significantly degrade their electrical and mechanical properties. Herein, we demonstrate a novel approach toward the large-scale dispersion of long and isolated SWCNTs by using hydrodynamic cavitation. Considering the results of atomic force microscopy and dynamic light-scattering measurements, the average length of the SWCNTs dispersed via the hydrodynamic cavitation method is larger than that of the SWCNTs dispersed by using an ultrasonic homogenizer.

Long-term treatment and prognostic factors of alpha 1-blockers for lower urinary tract symptoms associated with benign prostatic hyperplasia: a pilot study comparing naftopidil and tamsulosin hydrochloride.

OBJECTIVE: This study evaluated the 5-year failure rate of naftopidil (NAF) or tamsulosin hydrochloride (TAM) in lower urinary tract symptoms associated with benign prostatic hyperplasia (BPH/LUTS) and compared the prognostic factor of two alpha(1)-blockers. MATERIAL AND METHODS: A total of 131 patients with International Prostate Symptom Score (IPSS) >or= 8 or IPSS quality of life (IPSS-QOL) >or= 3 with BPH/LUTS receiving treatment with alpha(1)-blockers had been administered NAF or TAM, and failure rates were calculated for 5 years. Age, prostate volume (PV), acute urinary retention (AUR), overactive bladder (OAB), IPSS, IPSS-QOL and postvoiding residual volume (PVR) were evaluated as prognostic factors. RESULTS: No significant differences in failure rate were observed between the drugs. The failure rate was significantly high for patients with a PV >or= 35 ml, PVR >or= 30 ml, a history of AUR or complications of OAB symptoms. The failure rate for patients with a history of AUR was significantly higher than in those without AUR in the NAF group. By contrast, in the TAM group, it was significantly higher in patients who had OAB symptoms than in those without OAB. CONCLUSIONS: No significant differences were observed between the drugs for the failure rate. Each treatment had a unique factor for prognosis, such as history of AUR for NAF and complications of OAB for TAM. Therefore, it will be necessary to use the two alpha(1)-blockers properly, considering the patient's background.

Four-point probe resistance measurements using PtIr-coated carbon nanotube tips.

We performed four-terminal conductivity measurements on a CoSi2 nanowire (NW) at room temperature by using PtIr-coated carbon nanotube (CNT) tips in a four-tip scanning tunneling microscope. The physical stability and high aspect ratio of the CNT tips made it possible to reduce the probe spacing down to ca. 30 nm. The probe-spacing dependence of resistance showed diffusive transport even at 30 nm and no current leakage to the Si substrate.

Naftopidil monotherapy vs naftopidil and an anticholinergic agent combined therapy for storage symptoms associated with benign prostatic hyperplasia: A prospective randomized controlled study.

AIM: The aim of this study was to compare the efficacy and safety of alpha1-adrenoceptor (alpha1-AR) antagonist monotherapy with combination therapy using alpha1-AR antagonist and anticholinergic agent for benign prostatic hyperplasia (BPH) with storage symptoms as the chief complaint. METHODS: In this prospective comparative study, either 25-75 mg/day of naftopidil monotherapy (monotherapy group) or combination therapy using 25-75 mg/day of naftopidil and an anticholinergic agent (10-20 mg/day of propiverine hydrochloride or 2-6 mg/day of oxybutynin hydrochloride; cotherapy group) were administered for 12 weeks to 101 BPH patients with storage symptoms. RESULTS: International prostate symptom score (IPSS) and quality of life (QOL) index improved significantly in both groups, with no marked differences between groups. Maximum flow rate (Qmax) and residual urine volume (RUV) tended to improve in both groups, again with no marked differences between groups. However, median post-therapeutic RUV was significantly worse for the cotherapy group (45.0 mL) than for the monotherapy group (13.5 mL; P = 0.0210). Ratio of patients with increased RUV was also significantly worse for cotherapy (22.9%) than for monotherapy (5.0%; P = 0.038). CONCLUSIONS: Although the anticholinergic dosage was low, the present results suggest that naftopidil monotherapy was as useful as combination therapy of naftopidil and an anticholinergic agent. Therefore, naftopidil is a useful agent as the first choice in BPH patients with storage symptoms.