Recombinant protein of heptad-repeat HR212, a stable fusion inhibitor with potent anti-HIV action in vitro

HR212, a recombinant protein expressed in Escherichia coli, has been previously reported to inhibit HIV-1 membrane fusion at low nanomolar level. Here we report that HR212 is effective in blocking laboratory strain HIV-1IIIB entry and replication with EC50 values of 3.92±0.62 and 6.59±1.74 nM, respectively, and inhibiting infection by clinic isolate HIV-1KM018 with EC50 values of 44.44±10.20 nM, as well as suppressing HIV-1- induced cytopathic effect with an EC50 value of 3.04±1.20 nM. It also inhibited HIV-2ROD and HIV-2CBL-20 entry and replication in the μM range. Notably, HR212 was highly effective against T20-resistant strains with EC50 values ranging from 5.09 to 7.75 nM. Unlike T20, HR212 showed stability sufficient to inhibit syncytia formation in a time-of-addition assay, and was insensitive to proteinase K digestion. These results suggest that HR212 has great potential to be further developed as novel HIV-1 fusion inhibitor for treatment of HIV/ AIDS patients, particularly for those infected by T20-resistant variants.

PROTON-IMPLANTED NEW TYPE SILICON MATERIAL SUBJECTED TO 2-STEP FURNACE ANNEALING

A high-resistivity defect layer buried beneath the silicon surface layer by using proton implantation and two-step conventional furnace annealing is described. During the first annealing step (600-degrees-C), implanted hydrogen atoms move towards the damage region and then coalesce into hydrogen gas bubbles at the residual defect layer. During the second annealing step (1180-degrees-C) these bubbles do not move due to their large volume. Structural defects are formed around the bubbles at a depth of approximately 0.5-mu-m. The defect layer results in a high resistivity value. Experiments show that the quality of the surface layer has been improved because the surface Hall mobility increased by 20%. The sample was investigated by transmission electron microscopy.

Effect of a step quantum well structure and an electric-field on the Rashba spin splitting

Spin splitting of conduction subbands in Al_(0.3)Ga_(0.7)As/GaAs/Al_xGa_(1-x)As/Al_(0.3)Ga_(0.7)As step quantum wells induced by interface and electric field related Rashba effects is investigated theoretically by the method of finite difference. The dependence of the spin splitting on the electric field and the well structure, which is controlled by the well width and the step width, is investigated in detail. Without an external electric field, the spin splitting is induced by an in terface related Rashba term due to the built-in structure inversion asymmetry. Applying the external electric field to the step QW, the Rashba effect can be enhanced or weakened, depending on the well structure as well as the direction and the magnitude of the electric field. The spin splitting is mainly controlled by the interface related Rashba term under a negative and a stronger positive electric field, and the contribution of the electric field related Rashba term dominates in a small range of a weaker positive electric field.A method to determine the interface parameter is proposed.The results show that the step QWs might be used as spin switches.

Application of step-scan FTIR to the research of quantum cascade lasers

The principle of step-scan Fourier transform infrared （FTIR） spectroscopy is introduced. Double modulation step-scan FTIR technique is used to obtain the quantum cascade laser＇s stacked emission spectra in the time domain. Optical property and thermal accumulation of devices due to large drive current are analyzed.

The design of cascaded resistors in a new analog switch two-step ADC architecture

In this paper we introduce a new Half-flash analog switch ADC architecture. And we discuss two methods to design the values of the cascaded resistors which generate the reference voltages. Derailed analysis about the effect of analog switches and comparators on reference voltages, and the methods to set the resistor values and correspond;ng voltage errors are given.

Survivin表达在高LET射线诱导细胞凋亡中作用机理的初步研究；A Preliminary Study on Action Mechanisms of Survivin Expression in Cell Apoptosis Induced by High-LET Radiation

先前的研究表明,肿瘤细胞中survivin的高表达与细胞对高传能线密度(LET)射线的辐射抗性相关。研究了survivin表达在高LET射线诱导的细胞凋亡中的作用,发现抑制survivin表达对高LETC离子辐射诱导的Bcl-2和Bax表达没有明显的影响。在高LET射线辐照中,survivin可能通过抑制caspase-3和-9活性的途径,抑制了细胞凋亡。

UV-photooxidation as pretreatment step in inorganic analysis of environmental samples

Many laboratories deal with the determination of heavy metals, carbon, nitrogen and phosphorus. The first step in chemical analysis is a proper preparation of the investigated samples. The presence of organic substances can cause problems in many analytical methods. This paper describes the application of UV irradiation as a method of destruction of organic matter in the investigated samples.

One-Step Ionic Liquid-Assisted Electrochemical Synthesis of Ionic Liquid-Functionalized Graphene Sheet Directly from Graphite

Graphite, inexpensive and available in large quantities, unfortunately does not readily exfoliate to yield individual graphene sheets. Here a mild, one-step electrochemical approach for the preparation of ionic-liquid-functionalized graphite sheets with the assistance of an ionic liquid and water is presented. These ionic-liquid-treated graphite sheets can be exfoliated into functionalized graphene nanosheets that can not only be individuated and homogeneously distributed into polar aprotic solvents, but also need not be further deoxidized. Different types of ionic liquids and different ratios of the ionic liquid to water can influence the properties of the graphene nanosheets. Graphene nanosheet/polystyrene composites synthesized by a liquid-phase blend route exhibit a percolation threshold of 0.1 vol % for room temperature electrical conductivity, and, at only 4.19 vol %, this composite has a conductivity of 13.84 S m(-1), which is 3-15 times that of polystyrene composites filled with single-walled carbon nanotubes.

One-step preparation of hybrid materials of polyacrylamide networks and gold nanoparticles

Hybrid materials of polyacrylamide networks and gold nanoparticles were prepared by directly heating an aqueous solution containing HAuCl4, acrylamide, N,N'-methylenebisacrylamide, and sodium sulfite (Na2SO3). Acrylamide, N,N'-methylenebisacrylamide, and Na2SO3 were used as monomers, crosslinking agent, and initiator, respectively.