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BACKGROUND Iodine deficiency is an environmental health problem affecting one-third of the global population. An iodine biofortification hydroponic experiment was conducted to explore the iodide and iodate uptake characteristics of strawberry plants, to measure the dosage effects of iodine on plant growth and to evaluate the influence of I- or IO3-(More)
OBJECTIVE To isolate and identify active neuraminidase constituents of Polygonum cuspidatum against influenza A (H1N1) influenza virus. METHOD On the basis of the bioassay-guided fractionation,such chromatographic methods as silica gel, sephadex LH-20 and HPLC were adopted to isolate active constituents of extracts from Polygonum cuspidatum, and their(More)
BACKGROUND To study the arboviruses carried by mosquitoes collected in Hebei Province. METHODS Samples were collected from mosquito active sites and stored in liquid nitrogen till use. Pools of 20 to 30 mosquitoes were ground after sterilization, centrifugal supernant was inoculated onto C6/36 cell, cytopathic effect was observed for three sequential(More)
In this paper, a joint frame synchronization and channel estimation scheme using the regression method is proposed. Based on an OFDM frame format with adding the pseudo-noise code, the frame timing and the channel impulse response could be obtained by the proposed scheme. With the estimated channel information, a frequency domain one-tap equalizer is(More)
In this paper, a joint frame synchronization and channel estimation scheme is proposed. Based on an OFDM frame format with adding the pseudo-noise code, the frame timing and the channel impulse response could be obtained by the regression method at the OFDM receiver. The performances with the proposed frame and channel estimation scheme are evaluated by the(More)
In this paper, the control of analog cellular neural network systems via particle swarm optimization (PSO) approach is presented. A novel method for designing templates of a cellular neural network for gray-scale image noise cancellation is discussed. Based on the PSO method, this approach is used to design the templates of a cellular neural network and(More)
This paper proposes new acoustical features based on Hilbert Huang transform (HHT) for speaker identification. HHT is a powerful analysis method to obtain instantaneous frequency (IF). First, empirical ensemble empirical mode decomposition (EEMD) is used to generate intrinsic mode functions (IMFs). The Hilbert transform is then applied to IMFs to compute(More)
The volatile components of roots and stems of Zanthoxylum nitidum were investigated by supercritical fluid carbon dioxide extraction (SFE-CO2) and gas chromatography-mass spectrometry(GC-MS). Thirty-one and fifty-one compounds were identified in the supercritical extracts from roots and stems of Z. nitidum, respectively, and total twenty-seven compounds(More)