Positively charged liposomes consisting of the KTTKS pentapeptide conjugated with rhodamine increase rhodamine toxicity in E. coli and zebrafish embryo

Liposomes composed of cell‐penetrating peptide derivatives increased transport across the cell membrane. Conjugating rhodamine to a cell‐penetrating peptide increased the toxicity of rhodamine in E. coli and zebrafish embryos. A similar total protein inhibition pattern with different intensities, indicating that the interaction pathways of the rho‐KTTKS‐CONH₂ monomer and liposomes were the same. It suggests that the rho‐KTTKS‐CONH₂ liposomes showed higher toxicity because better transport across the cell membrane increased the effective concentration inside cells. The staining of zebrafish embryos using rho‐KTTKS‐CONH₂ liposomes showed a longer retention time, suggesting that it can penetrate deeper tissues or organs in zebrafish.     

Miscibility in a ternary system of poly(ether imide) with semicrystalline poly(ethylene terephthalate) and poly(butylene terephthalate)

A rare case of thermodynamic miscibility has been demonstrated in the amorphous state (quenched glass as well as molten state) of a ternary blend system formed by poly(ether imide) and semicrystalline poly(ethylene terephthalate) and poly-(butylene terephthalate). A single glass transition temperature (T_g) in the ternary blends was observed using differential scanning calorimetry and dynamic mechanical analysis.     

硫掺杂橄榄状BiVO4上可见光降解亚甲基蓝和甲醛水溶液性能

在无和有S源(Na₂S或硫脲)存在的条件下,采用十二胺辅助的醇-水热法制备了多孔单斜晶相结构的BiVO_4-δ和不同含量S掺杂的BiVO_4-δ光催化剂.利用多种手段表征了催化材料的物化性质,评价了它们在可见光照射下催化降解亚甲基蓝或甲醛的反应活性.结果表明,所制光催化剂为单斜白钨矿晶相结构,具有多孔橄榄状形貌,比表面积为8.4-12.5m²/g,带隙能为2.40-2.48eV.在S掺杂BiVO_4-δ表面同时含有Bi⁵⁺,Bi⁴⁺,V⁵⁺和V⁴⁺物种.S掺杂对BiVO_4-δ光催化剂的活性影响很大.在可见光下照射下,BiVO_4-δS_0.08光催化剂对亚甲基蓝和甲醛降解反应显示出最高的光催化活性,这与其较高的表面氧物种浓度和较低的带隙能相关.     

Magnetic resonance imaging of bone after radiation

Magnetic resonance imaging (MRI) was performed in 22 patients at various times (0-3) years) following radiation therapy to the spine. T1 and T2 weighted images were obtained at 0.5 Tesla. Increased signal was seen after 800-6000 rads (8-60 Gy). Marrow effects corresponded to radiation ports. Recurrent tumor was clearly separated from fatty replacement. This was much better seen on T1 weighted images. Five patients that had MRI during their course of radiotherapy (XRT) did not have increased signal on T1 images of the bone marrow. The earliest fatty marrow change was seen nine days following completion of 3000 rads (30 Gy) XRT over one month's duration. One patient who received 800 rads (8 Gy) to the upper thoracic spine for eosinophilic granuloma had no radiation effects on MRI when imaged 16 days following completion of XRT given over five days. Fatty marrow change was seen in this patient on MRI six months later. MRI was particularly useful in defining the extent of prior radiation effects when repeat therapy was needed.     

A multiple regression model for urban traffic noise in Hong Kong

This article describes the roadside traffic noise surveys conducted in heavily built-up urban areas in Hong Kong. Noise measurements were carried out along 18 major roads in 1999. The measurement data included L10, L50, L90, Leq, Lmax, the number of light vehicles, the number of heavy vehicles, the total traffic flow, and the average speed of vehicles. Statistical analysis using the analysis of variance (ANOVA) and Tukey test (p<0.05) reveals that the total traffic flow and the number of heavy vehicles are the most significant factors of urban traffic noise. Multiple regression was used to derive a set of empirical formulas for predicting L10 noise level due to road traffic. The accuracy of these empirical formulas is quantified and compared to that of another widely used prediction model in Hong Kong--the Calculation of Road Traffic Noise. The applicability of the selected multiple regression model is validated by the noise measurements performed in the winter of 2000.     

Decay Rates and Probability Estimates¶for Massive Dirac Particles¶in the Kerr–Newman Black Hole Geometry

The Cauchy problem is considered for the massive Dirac equation in the non-extreme Kerr–Newman geometry, for smooth initial data with compact support outside the event horizon and bounded angular momentum. We prove that the Dirac wave function decays in at least at the rate t ^−5/6. For generic initial data, this rate of decay is sharp. We derive a formula for the probability p that the Dirac particle escapes to infinity. For various conditions on the initial data, we show that p = 0, 1 or 0 < p < 1. The proofs are based on a refined analysis of the Dirac propagator constructed in [4]. Received: 20 August 2001 / Accepted: 22 January 2002 RID="*" ID="*"Present address: NWF I – Mathematik, Universit?t Regensburg, 93040 Regensburg, Germany.?E-mail: felix.finster@mathematik.uni-regensburg.de RID="**" ID="**"Research supported by NSERC grant # RGPIN 105490-1998. RID="***" ID="***"Research supported in part by the NSF, Grant No. DMS-0103998. RID="****" ID="****"Research supported in part by the NSF, Grant No. 33-585-7510-2-30.     

Fast response self-pumped phase conjugator based on a +c-face incident configuration in a pentagon-shaped BaTiO3 crystal

We propose a novel geometry for a self-pumped phase conjugator that uses a +c-face incident configuration in a photorefractive pentagon-shaped 0°-cut BaTiO₃ crystal for obtaining fast response in phase conjugation. A steady phase-conjugate output with a fast response time 0.4 s is obtained when the incident beam has a 4 W/cm² intensity. The influences of position and angle on the temporal phase-conjugate response are also investigated. The advantage of this phase conjugator using this novel configuration is improved resolution of a phase-distorted image with a value as high as 128 lp/mm.