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Becker's Nevus (BN) is a benign hamartoma with an esthetically troublesome condition secondary to hyperpigmentation and hypertrichosis. Many treatment modalities have been utilized with variable outcomes. To evaluate the efficacy and safety of intense pulsed light (IPL) in the treatment of BN. IPL was used at filter of 590 nm, fluence of 18–22 J/cm2, double-pulse mode (pulse width of 3–10 ms, pulse delay of 20–30 ms) at 3-month intervals. Final evaluations were performed by physician global assessment and patient satisfaction. Side effects were monitored at each treatment session and follow-up visit. Twenty-four patients (9 females, 15 males) with BN (16 hypertrichotic, 8 atrichotic) completed the study. The mean number of treatment sessions was 5 ± 2.17. The improvement in atrichotic BN group (4.87 ± 0.35) was significantly greater than that observed in hypertrichotic BN group (3.63 ± 0.89) (p =.001). Hair density simultaneously decreased with treatment in hypertrichotic BN. The mean satisfaction score was 5.75 ± 2.05 and 8 ± 0.93 in hypertrichotic and atrichotic BN groups respectively (p =.002). No repigmentation was noted during the follow-up period. No permanent side effects were observed. IPL is an effective and well-tolerated treatment option for patients with hypertrichotic and atrichotic BN. [ABSTRACT FROM AUTHOR]

Using the DC four-probe method, temperature dependence of the electrical resistivity (ρ − T) of Sb100− x Zn x (x = 25, 40, 50, 57, 61, 80 at%) alloys was investigated in the temperature range of 500–860°C. The results showed that resistivity of each liquid alloy decreased non-linearly with temperature increasing above their liquidus (T L) until reaching critical temperature, at which the resistivity–temperature coefficients dρ/dT–T converts from negative into positive. The phenomena of liquid phase transformation might relate with the dissociation of covalent bonds, chemical orders and associations in Sb–Zn melts. [ABSTRACT FROM AUTHOR]

D.C. four-probe method was used to investigate the temperature dependence of electrical resistivity of Sn-50wt%Sb melt. Anomalous changes observed on resistivity-temperature curves (ρ-T) suggest that temperature induced liquid-liquid structure transition (L-LST) might occur in Sn-50wt%Sb melt at hundreds of degrees above its liquidus, and the transition is reversible after the first heating cycle. An isothermal experiment based on ρ-T curve was conducted to further probe the effect of the L-LST on solidification morphologies. Results show that the size of the primary phase decreases and that the microstructure becomes finer when solidified from the melt experienced the irreversible L-LST. [ABSTRACT FROM AUTHOR]

The electrical resistivities of liquid Bi, Sb, and some of their alloys Pb-Bi, Pb-Sb have been investigated as a function of temperature, and the effect of heating-rate on the turning points of liquid Bi has also been investigated. Obvious and interesting hump phenomena are observed on resistivity-temperature curves of liquid Bi, Sb, and Pb-Bi, Pb-Sb alloys on heating at the temperature far above their liquidus. Moreover, the transition temperature of liquid Bi increases with heating-rate increasing, which shows that this kind of transition is in accordance with kinetic characteristics. However, comparing the heating curve with the cooling one, we found that the anomalous hump phenomenon is irreversible in liquid Bi, Sb, and Pb-Bi, Pb-Sb alloys. [ABSTRACT FROM AUTHOR]