No abstract

Lasing action in an In0.1Ga0.9N vertical cavity surface emitting laser was successfully achieved, for the first time, at a wavelength of 381 nm. The 3λ vertical cavity comprising an In0.1Ga0.9N active region was grown on a GaN/Al0.34Ga0.66N quarter-wave reflector by metal organic chemical vapor deposition (MOCVD), and covered with a TiO2/SiO2 reflector by electron-beam evaporation. The laser was operated at 77 K under optical excitation. We have observed a significant narrowing of the emission spectrum from 2.5 nm below the threshold to 0.1 nm (resolution limit) above the threshold, which is a clear signature of lasing action.

The in vitro cell tests and in vivo animal tests were performed to investigate the feasibility of the photothermal therapy based on porous silicon (PSi) in combination with near-infrared (NIR) laser. According to the Annexin V- fluorescein isothiocyanate Apoptosis assay test results, the untreated cells and the cells exposed to NIR laser without PSi treatment had a cell viability of 95.6 and 91.3%, respectively. Likewise, the cells treated with PSi but not with NIR irradiation also had a cell viability of 74.4%. Combination of these two techniques, however, showed a cell viability of 6.7%. Also, the cell deaths were mostly due to necrosis but partly due to late apoptosis. The in vivo animal test results showed that the Murine colon carcinoma (CT-26) tumors were completely resorbed without nearly giving damage to surrounding healthy tissue within 5 days of PSi and NIR laser treatment. Tumors have not recurred at all in the PSi/NIR treatment groups thereafter. Both the in vitro cell test and in vivo animal test results suggest that thermotherapy based on PSi in combination with NIR laser irradiation is an efficient technique to selectively destroy cancer cells without damaging the surrounding healthy cells.

In this paper, we present a correlation attack on Sosemanuk with complexity less than 2 150. Sosemanuk is a software oriented stream cipher proposed by Berbain et al. to the eSTREAM call for stream cipher and has been selected in the final portfolio. Sosemanuk consists of a linear feedback shift register(LFSR) of ten 32-bit words and a finite state machine(FSM) of two 32-bit words. By combining linear approximation relations regarding the FSM update function, the FSM output function and the keystream output function, it is possible to derive linear approximation relations with correlation −2 −21.41 involving only the keystream words and the LFSR initial state. Using such linear approximation relations, we mount a correlation attack with complexity 2 147.88 and success probability 99% to recover the initial internal state of 384 bits. We also mount a correlation attack on SNOW 2.0 with complexity 2 204.38 .

There has been growing concern over human exposure to adenoviruses through drinking water due to their apparent high resistance to UV irradiation and the anticipated widespread use of ultraviolet (UV) disinfection in drinking water treatment processes. However, most inactivation studies on adenoviruses were performed using only one type of UV technology--low-pressure (LP) UV, and little is known about the effectiveness of different UV technologies such as medium- pressure (MP) UV or other polychromatic UV technologies. In this work, the kinetics and extent of inactivation of a human adenovirus (adenovirus 2 (Ad2)) by both monochromatic LP and polychromatic MP UV were evaluated to determine the effectiveness of these UV technologies on human adenoviruses. Inactivation of Ad2 by LP UV was very slow and only 0.87 and 2.17 log(10) inactivation was achieved with UV doses of 30 and 90 mJ/cm(2), respectively. However, inactivation of Ad2 by MP UV was much faster and 2.19 and 5.36 log(10) inactivation was observed with the same UV doses (30 and 90 mJ/cm(2), respectively). It appears that MP UV is more effective against Ad2 than LP UV and the enhanced effectiveness of MP UV on Ad2 is likely due to its ability to inhibit the repair process in UV-irradiated Ad2.