5,556 research outputs found

    Faces, Locations, and Tools: A Proposed Two-Stimulus p300 Brain Computer Interface

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    Objective. Brain computer interface (BCI) technology can be important for those unable to communicate due to loss of muscle control. Given that the P300 Speller provides a relatively slow rate of communication, highly accurate classification is of great importance. Previous studies have shown that alternative stimuli (e.g. faces) can improve BCI speed and accuracy. The present study uses two new alternative stimuli, locations and graspable tools. Functional MRI studies have shown that images of familiar locations produce brain responses in the parahippocampal place area and graspable tools produce brain responses in premotor cortex. Approach. The current studies show that location and tool stimuli produce unique and discriminable brain responses that can be used to improve offline classification accuracy. Experiment 1 presented face stimuli and location stimuli and Experiment 2 presented location and tool stimuli. Main results. In both experiments, offline results showed that a stimulus specific classifier provided higher accuracy, speed, and bit rate. Significance. This study was used to provide preliminary offline support for using unique stimuli to improve speed and accuracy of the P300 Speller. Additional experiments should be conducted to examine the online efficacy of this novel paradigm

    Bistable molecular conductors with a field-switchable dipole group

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    A class of bistable "stator-rotor" molecules is proposed, where a stationary bridge (stator) connects the two electrodes and facilitates electron transport between them. The rotor part, which has a large dipole moment, is attached to an atom of the stator via a single sigma bond. Hydrogen bonds formed between the rotor and stator make the symmetric orientation of the dipole unstable. The rotor has two potential minima with equal energy for rotation about the sigma bond. The dipole orientation, which determines the conduction state of the molecule, can be switched by an external electric field that changes the relative energy of the two potential minima. Both orientation of the rotor correspond to asymmetric current-voltage characteristics that are the reverse of each other, so they are distinguishable electrically. Such bistable stator-rotor molecules could potentially be used as parts of molecular electronic devices.Comment: 8 pages, 7 figure

    Adolescent mothers' utilisation of reproductive health services in the Gauteng Province of the Republic of South Africa

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    A financial grant was received from the World Health Organization (WHO) during 1998 to establish whether adolescent mothers (aged 19 or younger at the birth of their babies) utilized contraceptive, emergency contraceptive and termination of pregnancy (TOP) services in the Republic of South Africa (RSA). This report refers to data obtained from 111 questionnaires completed by dolescent mothers between January 2000 and May 2000 in the Gauteng Province; 61 in the Pretoria and 50 in the Garankuwa areas, and excluding the 12 completed questionnaires used foi pretesting the research instrument. The biographic data of the 111 adolescent mothers indicated that the minority were married, employed or earned sufficient income to care for themselves and their babies. However, the minority used contraceptives prior to conception, none used emergency contraceptives or termination of pregnancy (TOP) services. The minority attended ante-natal clinics five or more times during their pregnancies, and a negligible number indicated that they had ever been treated for sexually transmitted diseases (STDs). These findings indicate that the 111 adolescent mothers in Gauteng who participated in this survey did not make optimum use of the available reproductive health (RH) care services. Education about sex, pregnancy and contraceptives should commence at the age of 10, but no later than the age of 12 as the majority of respondents did not have the necessary knowledge to make informed decisions about their futures. The accessibility of contraceptive, emergency contraceptive , s and TOP services for adolescents should be investigated in .< \ v specific areas and attempts made to enhance such accessi- \ ; bility. This might necessitate offering these services over weeker| ds or during evenings when school girls could attend without fear of meeting their mothers, aunts or teachers at these clinicsHealth Studie

    Banking from Leeds, not London: regional strategy and structure at the Yorkshire Bank, 1859–1952

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    Industrial philanthropist Edward Akroyd created the Yorkshire Penny Savings Bank in 1859. Despite competition from the Post Office Savings Bank after 1861 and a serious reserve problem in 1911, it sustained his overall strategy to become a successful regional bank. Using archival and contemporary sources to build on recent scholarship illustrating how savings banks were integrated into local economies and the complementary roles of philanthropy and paternalism, we analyse an English regional bank's strategy, including an assessment of strategic innovation, ownership changes and management structure. This will demonstrate that the founder's vision continued, even though the 1911 crisis radically altered both strategy and structure

    Important HIV-associated conditions in HIV-infected infants and children

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    This article is the last in a series of 6 articles that discussed the management of HIV-infected children in a clinically orientated, practical and concise fashion. The topics covered previously include; 1) Preventing and diagnosing HIV-infection in infants and children, 2) Initiating anti-retroviral therapy in HIV-infected infants and children, 3) Maintaining HIV-infected infants and children on anti-retroviral therapy, 4) Common opportunistic infection in HIV-infected children: Part 1-respiratory infections and 5) Part 2 non-respiratory infections. South African Family Practice Vol. 49 (4) 2007: pp.19-2

    Speakers and the Spotlight: Explaining Media Coverage of Leadership in the House of Representatives

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    Previous scholarship has described how members of Congress struggle to attract media attention. The Speaker of the House, however, is uniquely positioned to drive media agendas. That position may be conditioned though by the framework in which the Speaker operates, shocks to the system of leadership in the House, and the process of legislating. We inquire into the conditions under which the Speaker of the House receives increased or decreased attention from newspapers, network newscasts, and cable newscasts. We also examine the contraction and expansion of the gap between levels of presidential and Speaker coverage. We find that Speaker coverage is often shaped by increases in House polarization, changes in which party holds the position, Speaker scandal, and turning bills into laws.Yeshttps://us.sagepub.com/en-us/nam/manuscript-submission-guideline
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