The brown planthopper, Nilaparvata lugens, is the most devastating rice insect pest to have given rise to an outbreak in recent years. RNA interference (RNAi) is a technological breakthrough that has been developed as a powerful tool for studying gene function and for the highly targeted control of insect pests. Here, we examined the effects of using a feeding-based RNAi technique to target the gene trehalose phosphate synthase (TPS) in N. lugens. The full-length cDNA of N. lugens TPS (NlTPS) is 3235 bp and has an open reading frame of 2424 bp, encoding a protein of 807 amino acids. NlTPS was expressed in the fat body, midgut and ovary. Quantitative real-time PCR (qRT-PCR) analysis revealed that NlTPS mRNA is expressed continuously with little change during the life of the insect. Efficient silencing of the TPS gene through double-stranded RNA (dsRNA) feeding led to rapid and significant reduction levels of TPS mRNA and enzymatic activity. Additionally, the development of N. lugens larvae that had been fed with the dsRNA was disturbed, resulting in lethality, and the cumulative survival rates dropped to 75.56, 64.44, 55.56 and 40.00% after continuous ingestion of 0.5 µg/µl dsRNA for 2, 4, 7 and 10 days, respectively. These values were significantly lower than those of the insects in the control group, suggesting that NlTPS dsRNA may be useful as a means of insect pest control.

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Recent advances in the development of microplasma devices fabricated in a variety of materials systems (Si, ceramic multilayers, and metal/polymer structures) and configurations are reviewed. Arrays of microplasma emitters, having inverted pyramidal Si electrodes or produced in ceramic multilayer sandwiches with integrated ballasting for each pixel, have been demonstrated and arrays as large as 30×30 pixels are described. A new class of photodetectors, hybrid semiconductor/microplasma devices, is shown to exhibit photoresponsivities in the visible and near-infrared that are more than an order of magnitude larger than those typical of semiconductor avalanche photodiodes. Microdischarge devices having refractory or piezoelectric dielectric films such as Al 2 O 3 or BN have extended lifetimes (∼86% of initial radiant output after 100 h with an Al 2 O 3 dielectric) and controllable electrical characteristics. A segmented, linear array of microdischarges, fabricated in a ceramic multilayer structure and having an active length of ∼1 cm and a clear aperture of 80 × 360 µm 2 , exhibits evidence of gain on the 460.3 nm transition of Xe + , making it the first example of a microdischarge-driven optical amplifier.

A nanodiamond thin film is deposited on a single crystal silicon substrate by dip-coating technique. Surface characterization of the unannealed nanodiamond sample, and the samples annealed at various temperatures in nitrogen ambient, is conducted by XPS and Raman spectroscopy. The fitting data of the C1s core level XPS peak reveal that the sp 2 /sp 3 ratio in the unannealed sample and the sample annealed at 900• C and 1500• C are 0.44, 0.55 and 6.08 respectively. All spectra including the C1s core level XPS spectrum, the plasmon energy-loss spectrum associated with C1s peak, C KVV Auger spectrum of the sample annealed at 900• C are similar to those of the unannealed sample. However, the spectra of the sample annealed at 1500• C are very different. Annealing at 900• C fails to produce appreciable graphitization, and an onion-like carbon structure with a small diamond core is formed when the nanodiamond is heated to 1500• C. Copyright c 2010 John Wiley & Sons, Ltd.Keywords: X-ray photoelectron spectroscopy (XPS); Raman spectroscopy; nanodiamond; sp 2 -hybridised; sp 3 -hybridised IntroductionNanodiamond is a potential cold cathode material in the electron field emission process [1,2] and has potential application in vacuum micro-and nanoelectronic devices. [3] The unique properties of nanodiamond are directly related to the microscopic structure, elemental and carbon bonding structure. [4] It is well known that the structure property of carbon material is determined by the sp 2 /sp 3 bonding ratio. Thermoannealing is an effective method to alter the structure of carbon material.[5] High-temperature annealing not only varies the chemical bonding structure of carbon material but also affects its field emission property. [6,7] The formation of a large fraction of sp 2 bonding carbon in the DLC film plays an important role in the enhancement of field emission property. [6] So far, in order to characterize carbon materials, a correct estimate of the abundance of sp 2 -hybridised atoms is of extraordinary importance. Raman spectroscopy can be used to identify sp 2 and sp 3 hybrids in C-based material owing its high sensitivity to light scattering. However, Raman technique has a poor capability in quantitative analysis. XPS can be used to estimate the fraction of sp 2 -hybridised atoms in carbonaceous materials. [8,9] XPS is a surface analytical technique which provides both chemical and binding information for a variety of materials. For carbon materials, the C 1s core energy level at around 280-290 eV, [10] the plasmon-loss energy at around 0-60 eV relative to C1s main peak [11] and the X-ray-excited Auger peaks at higher binding energy [11] all give phase information on the carbon present. Fitting the C1s core level peak is a common method used to quantify the sp 2 hybrids in C-based material. The C1s photoelectrons whose loss features reflects the different bond organization, and the Auger region whose width is correlated to the amount of sp 2 hybridised C-atoms. [12] In this paper, the unannealed nanodiamond sample a...