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61.

This paper is concerned with Electroencephalography (EEG) seizure prediction, which means the detection of the pre-ictal state prior to ictal activity occurrence. The basic idea of the proposed approach for EEG seizure prediction is to work on the signals in the Hilbert domain. The operation in the Hilbert domain guarantees working on the low-pass spectra of EEG signal segments to avoid artifacts. Signal attributes in the Hilbert domain including amplitude, derivative, local mean, local variance, and median are analyzed statistically to perform the channel selection and seizure prediction tasks. Pre-defined prediction and false-alarm probabilities are set to select the channels, the attributes, and bins of probability density functions (PDFs) that can be useful for seizure prediction. Due to the multi-channel nature of this process, there is a need for a majority voting strategy to take a decision for each signal segment. Simulation results reveal an average prediction rate of 96.46%, an average false-alarm rate of 0.028077/h and an average prediction time of 60.1595 min for a 90-min prediction horizon.

  相似文献   
62.
The intense electromagnetic fields of plasmonic nanoparticles, resulting from the excitation of their localized surface plasmon oscillations, are known to enhance radiative processes. Their effect on the nonradiative electronic processes, however, is not as well-documented. Here, we report on the enhancement of the nonradiative electronic relaxation rates in CdTe nanowires upon the addition of a thin gold nanoshell, especially at excitation energies overlapping with those of the surface plasmon oscillations. Some possible mechanisms by which localized surface plasmon fields can enhance nonradiative relaxation processes of any quantized electronic excitations are proposed.  相似文献   
63.
The grass webworm Herpetogramma licarsisalis (Lepidoptera: Crambidae), which has recently established in pasture in Northland, New Zealand, is an important pest of many tropical and subtropical grasses. Two pheromone components, (Z)-11-hexadecen-1-yl acetate (Z11–16:Ac) and (11Z,13E)-hexadecadien-1-yl acetate (Z11,E13–16:Ac), were identified in pheromone gland extracts of female moths by gas chromatography (GC), GC-electroantennographic detection, and GC-mass spectrometry in conjunction with microchemical tests (dimethyldisulfide and 4-methyl-1,2,4-triazoline-3,5-dione derivatizations). Z11,E13–16:Ac and its geometric isomer (11E,13Z)-hexadecadien-1-yl acetate (E11,Z13–16:Ac) were synthesized via stereoselective Wittig reactions, and the identity of the diene present in the pheromone glands was confirmed to be Z11,E13–16:Ac. Field bioassays at Indooroopilly in Brisbane, Australia, established that Z11,E13–16:Ac was necessary and sufficient for attraction of male grass webworm moths and that the corresponding alcohol, (11Z,13E)-hexadecadien-1-ol (Z11,E13–16:OH), had a strong inhibitory effect on trap catches at the ratios tested. When mixed with Z11,E13–16:Ac in various ratios, Z11–16:Ac had no effect on the attractiveness of lures. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
64.
Huang W  Qian W  Jain PK  El-Sayed MA 《Nano letters》2007,7(10):3227-3234
By using electron beam lithography, we fabricated pairs of gold nanoparticles with varying interparticle separation. Double-beam femtosecond transient absorption spectroscopy was used to determine the coherent lattice oscillation frequency as a function of the interparticle separation in the presence of the plasmon field excited by the monitoring probe light. We found that the fractional shift in the coherent lattice phonon oscillation frequency follows an exponential decay with respect to the interparticle gap scaled by the disc diameter with the same decay constant as that previously observed for the fractional shift in the surface plasmon electronic oscillation resonance frequency. This strongly suggests that it is the near-field coupling between the particles that shifts both the coherent electronic oscillation (plasmon) frequency and the coherent lattice oscillation (phonon) frequency. The similar trend in the effect of interparticle coupling on the plasmon frequency and the phonon frequency is essentially a reflection of the universal scaling behavior of the distance decay of the interparticle plasmonic near-field. It is shown that the observed decrease in the lattice oscillation frequency with decrease in the interparticle distance is the result of a reduction in the effective free electron density within each nanoparticle pair partner as a result of the polarizing perturbation of the plasmonic field of the other nanoparticle in the pair.  相似文献   
65.
A recursive least-squares digital distance relaying algorithm   总被引:1,自引:0,他引:1  
A new digital distance relaying algorithm based on the well-known theory of least-squares is developed, and the results of testing it using numerical simulation are presented. The new technique estimates the distance to the fault and the fault resistance. To minimize the computational requirements of the digital relay, a recursive least-squares approach is used. Computer simulation results of the new least-squares algorithm seem promising, indicating that it should be considered for further testing and evaluation  相似文献   
66.
In an effort to discover potent anticancer agents, 2-thiouracil-5-sulfonamides derivatives were designed and synthesized. The cytotoxic activity of all synthesized compounds was investigated against four human cancer cell lines viz A-2780 (ovarian), HT-29 (colon), MCF-7 (breast), and HepG2 (liver). Compounds 6b,d–g, and 7b showed promising anticancer activity and significant inhibition of CDK2A. Moreover, they were all safe when tested on WI38 normal cells with high selectivity index for cancer cells. Flow cytometric analysis for the most active compound 6e displayed induction of cell growth arrest at G1/S phase (A-2780 cells), S phase (HT-29 and MCF-7 cells), and G2/M phase (HepG2 cells) and stimulated the apoptotic death of all cancer cells. Moreover, 6e was able to cause cycle arrest indirectly through enhanced expression of cell cycle inhibitors p21 and p27. Finally, molecular docking of compound 6e endorsed its proper binding to CDK2A, which clarifies its potent anticancer activity.  相似文献   
67.
Efforts have been done to recover proteins from waste liquors rich in protein in a soluble form. Cheese whey and animal bloods are byproducts from the manufacture of cheese and meat. It contains a variety of proteins which can be reclaimed. The efficiency of protein precipitation from the sweet-cheese whey by the use of hydroxyethyl cellulose (HEC) was similar to that precipitated by the use of carboxymethyl cellulose (CMC). Both are greater than that precipitated by trichloro acetic acid. The same results of the efficiency of precipitation were attained when the plasma protein was precipitated. It was found that cheesewhey protein-HEC-complex and plasms protein-HEC-complex contain a large amount of essential amino acids. Electrophoretic separation of whey protein complex showed that β-Lactoglobulin forms the major fraction while in case of plasma protein complex albumin forms the major fraction. The fractionation patterns of different complexes with HEC, CMC or TCA gave the same components and about the same ratio. It appears from these results that HEC-protein complexes are preferable than CMC-protein complexes or proteins precipitated by TCA. Chemical analysis of whey protein complexes revealed that lactose content of whey protein-HEC-complex was higher than that of CMC-complex or protein precipitated by TCA. Elemental analysis of protein complexes showed that the level of sodium, phosphorus, and potassium was increased while that of copper or zinc decreased. Cellulose derivative protein complexes showed no significant effects on the liver or kindney function of albino rat and these results indicated that no toxic effect was observed from the uses of these protein complexes in feeding.  相似文献   
68.
A novel method is applied to produce amorphous carbon thin film (ACTF) from oil palm leaves. The novel prepared ACTF is in the form of thin films like graphene sheets having winding surface. ACTF was characterized by different methods of characterization: FTIR, BET, SEM, EDX, TEM, and Raman. ACTF employed as an adsorbent to separate emulsified condensate oil from synthetic produced water as a treatment process before reinjection in oil reservoirs. The adsorption performance of batch and fixed bed adsorption systems were investigated. Contact time, initial concentration of condensate oil (Co = 100–2500 mg/l) and temperature were studied by batch experiments. The obtained results indicated that the adsorption capacity and the removal efficiency increased with time up to 132.77 mg condensate/g adsorbent and 66.38% respectively, within 6 h equilibrium time at 308 K. The thermodynamic adsorption experiments conducted at 288, 308 and 318 K, referring exothermic nature of the adsorption process.The performance study of fixed bed adsorption described through the breakthrough curves concept with two parameters: column bed heights (5, 10 and 15 mm) and flow rate (2.2, 5 and 8.4 ml/min). Two models (Thomas and Yoon-Nelson models) were applied to expect different parameters of fixed bed as adsorption capacity and time need for 50% breakthrough. The results exhibited that 2.2 ml /min feed flowrate and 5 mm bed height at 1000 mg/l initial oil condensate concentration were the optimum conditions for the ACTF column. The experimental breakthrough curves showed acceptable fit with the calculated breakthrough profiles obtained by Thomas model.  相似文献   
69.
El-Sayed H  Singh S  Greiner MT  Kruse P 《Nano letters》2006,6(12):2995-2999
We show that electropolishing of tantalum metal in a single step of about 5 min can reproducibly lead to dimples tens of nanometers in diameter, regular in shape, monodispersed in size, and arranged in highly ordered arrays which even transverse grain boundaries. Dimpled tantalum is ductile, high melting, and chemically inert, which makes it suitable for nanostructure synthesis even under extreme conditions, as demonstrated with a simple sputter coating and flame annealing procedure for gold nanoparticles.  相似文献   
70.
The protein A encoding gene spa of four Staphylococcus aureus strains isolated from bovine clinical mastitis was amplified by PCR and sequenced. The four strains were selected after an initial screening of spa gene of 41 strains isolated from mastitic cows and were subjected to detailed investigations. According to the sequencing results the spa gene of three strains (M1, M2, M3) appeared with gene segments encoding five (E, D, A, B and C) and four (E, A, B and C) IgG binding domains for two (M1, M3) and one (M2) strain, respectively and with gene segments encoding four, two and two repeats of the octapeptide Xr-repeats for the strains M1, M2 and M3, respectively. For the remaining Staph. aureus strain (M4) gene segments encoding IgG binding domains E, D and A and a new domain BC with a size of 219 bp could be observed. The BC domain appears, with a deletion of a 123 bp segment from the border region between both domains, as fused domain of both previously characterized domains. The Xr-region of this strain had 11 octapeptide repeats.  相似文献   
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