Non-target Ones Research Articles

Влияние эмоциональной экспрессии нерелевантного лицевого изображения на опознание зрительных стимулов

In 34 healthy subjects we have analyzed accuracy and reaction time (RT) during the recognition of complex visual images: pictures of animals and non-living objects. The target stimuli were preceded by brief presentation of masking non-target ones, which represented drawings of emotional (angry, fearful, happy) or neutral faces. We have revealed that in contrast to accuracy the RT depended on the emotional expression of the preceding faces. RT was significantly shorter if the target objects were paired with the angry and fearful faces as compared with the happy and neutral ones. These effects depended on the category of the target stimulus and were more prominent for objects than for animals. Further, the emotional faces' effects were determined by emotional and communication personality traits (defined by Cattell's Questionnaire) and were clearer defined in more sensitive, anxious and pessimistic introverts. The data are important for understanding the mechanisms of human visual behavior determination by non-consciously processing of emotional information.

Influence of the insecticide pyriproxyfen on the flight muscle differentiation of Apis mellifera (Hymenoptera, Apidae)

The Brazilian africanized Apis mellifera is currently considered as one of the most important pollinators threatened by the use of insecticides due to its frequent exposition to their toxic action while foraging in the crops it pollinated. Among the insecticides, the most used in the control of insect pragues has as active agent the pyriproxyfen, analogous to the juvenile hormone (JH). Unfortunately the insecticides used in agriculture affect not only the target insects but also beneficial nontarget ones as bees compromising therefore, the growth rate of their colonies at the boundaries of crop fields. Workers that forage for provisions in contaminated areas can introduce contaminated pollen or/and nectar inside the beehives. As analogous to JH the insecticide pyriproxyfen acts in the bee's larval growth and differentiation during pupation or metamorphosis timing. The flighty muscle is not present in the larvae wingless organisms, but differentiates during pupation/metamorphosis. This work aimed to investigate the effect of pyriproxyfen insecticide on differentiation of such musculature in workers of Brazilian africanized honey bees fed with artificial diet containing the pesticide. The results show that the bees fed with contaminated diet, independent of the insecticide concentration used, show a delay in flight muscle differentiation when compared to the control.

Enhancing P300 wave of BCI systems via negentropy in adaptive wavelet denoising

Brian Computer Interface (BCI) is a direct communication pathway between the brain and an external device. BCIs are often aimed at assisting, augmenting or repairing human cognitive or sensory-motor functions. EEG separation into target and non-target ones based on presence of P300 signal is of difficult task mainly due to their natural low signal to noise ratio. In this paper a new algorithm is introduced to enhance EEG signals and improve their SNR. Our denoising method is based on multi-resolution analysis via Independent Component Analysis (ICA) Fundamentals. We have suggested combination of negentropy as a feature of signal and subband information from wavelet transform. The proposed method is finally tested with dataset from BCI Competition 2003 and gives results that compare favorably.

An Auditory Brain–Computer Interface Using Active Mental Response

This study proposes a novel auditory brain-computer interface paradigm, which allows the subject to mentally select a target among a random sequence of spoken digits. The subject's voluntary recognition of the property of the target digits enhances the discriminability between brain responses to target and nontarget digits. EEG data from 14 subjects has shown that the amplitude of N2 and the late positive component (LPC) elicited by target digits was significantly higher than that of nontarget ones. Three classification methods, i.e., N2/LPC area comparison, Fisher discriminant analysis and support vector machine (SVM), were adopted to assess the target detection accuracy using EEG data from a single electrode. For SVM classification, a mean accuracy of 85% was achieved with five trials averaged. This new paradigm could be useful for locked-in patients with vision impairment.

Continuous Foam Separation of Metals Enhanced by Down-Flowing Surfactant Solution from Column Top

A novel operational mode of foam separation was suggested in this study. In a conventional operation, the separation of a target solute has its own limit because non-target ones exist in the interstitial water between foam and get mixed in the recovered foamate solution. As a countermeasure for this inherent drawback in foam separation, an aqueous surfactant solution was injected into the rising foam bed to enhance a downflow of the interstitial water containing unfavourable solutes. The flow characteristics of the system with and without the injection of a washing solution were investigated in terms of the liquid holdup, ϕ and the drainage velocity, U LD, under various operating conditions. Their correlation was obtained as U LD (cm s −1) = 1.85 ϕ 2 + 0.0005. The application to metal separation was also performed using a nonionic surfactant, polyoxyethylene nonylphenyl ether (PONPE 20), with an affinity to Au(III). The non-specific metal, Cu(II), was effectively washed out from the foam bed, and satisfactory separation of Au(III) was attained.

Discrimination of All Types of 4-Bit Optical Code by Optical Time-Gating and Designed Label Recognition Filter in Label Recognition Using Optical Correlation

In label recognition based on optical correlation processing, to completely discriminate a 4-bit target optical code from all types of 4-bit nontarget ones, we propose a novel label recognition method using both optical time-gating and the designed label recognition filter. We experimentally demonstrate that the intensities of correlation signals of 4-bit similar optical codes can be suppressed by the designed label recognition filter and that only the correlation signal of a 4-bit target optical code can be detected by extraction with optical time-gating. The optical time-gating is realized by using organic nonlinear optical crystal: 2-adamantylamino-5-nitropyridine (AANP).

Suppression of Crosstalk in Header Recognition Based on Optical Correlation using Multiple-Object Discriminant Filter

We demonstrate that crosstalk caused by matched filtering can be suppressed by designing a header recognition filter in the header recognition unit based on optical correlation processing. The header recognition filter is designed using a technique of a multiple-object discriminant filter (MODF). Results of preliminary experiments show that the designed header recognition filter can suppress crosstalk. The peak intensity ratio of correlation signals of a target header signal to those of nontarget ones is higher than 1.48:1 in the case of 4-bit header signals. The number of discriminable header signals could markedly increase using the designed header recognition filter.

Design of Header Recognition Filter for Binary Phase Shift Keying in Header Recognition Unit using Time-Space Conversion

Optical header recognition is one key function that enables ultrafast optical routing in photonic packet-switched networks. Especially, optical header recognition based on optical correlation processing has attracted much attention. Header signals using optical codes are decoded using optical correlation processing. We improve the decoding method for Binary Phase Shift Keying (BPSK) header signals in order to suppress crosstalk caused by matched filtering in the header recognition unit. We design a header recognition filter using the technique of a multiple-object discriminant filter (MODF). Results of preliminary experiments show that the designed header recognition filter can suppress crosstalk. The intensity ratio of correlation signals of a target header signal to non-target ones is higher than 1.95 : 1 in case of 4-bits BPSK header signals.

Selective detection of specific bacteria using dielectrophoretic impedance measurement method combined with an antigen–antibody reaction

This paper describes a new selective detection method for specific bacteria by using a dielectrophoretic impedance measurement method combined with an antigen–antibody reaction. The authors have previously proposed a bacteria detection technique called dielectrophoretic impedance measurement (DEPIM) using positive dielectrophoretic force to capture bacteria in suspension onto an interdigitated microelectrode array. In this paper, the authors propose a selective bacteria detection method using DEPIM combined with an antigen–antibody reaction. A suspension containing Escherichia coli ( E. coli) and Serratia marcescens ( Serratia) was tested as a sample specimen. Those two bacteria were captured onto a microelectrode by positive dielectrophoresis in almost equal amounts. Agglutination of target bacteria caused by an antigen–antibody reaction was combined with conventional DEPIM in two different ways. As a result of agglutination, target bacteria became larger than nontarget ones and could experience higher dielectrophoretic force. In one method, E. coli and Serratia were trapped together under positive dielectrophoresis and then agglutinated E. coli was selectively left in the electrode gap by washing process. In the other method, agglutination products, which had been produced in advance, were selectively trapped and detected by DEPIM. It was experimentally confirmed that proposed two methods could selectively detect E. coli from the mix suspension as long as E. coli population was more than that of Serratia.

Thermal asymmetric interlaced PCR: automatable amplification and sequencing of insert end fragments from P1 and YAC clones for chromosome walking

Isolation of DNA segments adjacent to known sequences is a tedious task in genome-related research. We have developed an efficient PCR strategy that overcomes the shortcomings of existing methods and can be automated. This strategy, thermal asymmetric in-ter laced (TAIL)-PCR, utilizes nested sequence-specific primers together with a shorter arbitrary degenerate primer so that the relative amplification efficiencies of specific and nonspecific products can be thermally controlled. One low-stringency PCR cycle is carried out to create annealing site(s) adapted for the arbitrary primer within the unknown target sequence bordering the known segment. This sequence is then preferentially and geometrically amplified over nontarget ones by interspersion of high-stringency PCR cycles with reduced-stringency PCR cycles. We have exploited the efficiency of this method to expedite amplification and sequencing of insert end segments from P1 and YAC clones for chromosome walking. In this study we present protocols that are amenable to automation of amplification and sequencing of insert end sequences directly from cells of P1 and YAC clones.