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991.
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OBJECTIVE: To examine the relationship between attention deficit disorder with hyperactivity in childhood and criminality in adolescence and adulthood in 89 hyperactive and 87 normal control subjects. METHOD: In this prospective study, adolescent follow-up intervals ranged from 13 to 21 years and adult follow-up ranged from 18 to 23 years. The official arrest records for all subjects were obtained. RESULTS: Hyperactive subjects had significantly higher juvenile (46% versus 11%) and adult (21% versus 1%) arrest rates. Juvenile and adult incarceration rates were also significantly higher. Childhood conduct problems predicted later criminality, and serious antisocial behavior in adolescence predicted adult criminality. CONCLUSIONS: Hyperactive children are at risk for both juvenile and adult criminality. The risk for becoming an adult offender is associated with conduct problems in childhood and serious antisocial behavior (repeat offending) in adolescence. Hyperactive children who do not have conduct problems are not at increased risk for later criminality.  相似文献   
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As discussed in this paper, a practical optical backplane system was demonstrated, using a waveguide-embedded optical backplane board, processing boards, and optical slots for board-to-board interconnection. A metal optical bench was used as a packaging die for the optical devices and the integrated circuit chips in both the transmitter and the receiver processing boards. The polymer waveguide was produced by means of a hot-embossing technique and was then embedded following a conventional lamination processes. The average propagation loss of these waveguides was approximately 0.1 dB/cm at 850 nm. The dimension and optical properties of the waveguide in an optical backplane board were unchanged after lamination. As connection components between transmitter/receiver processing boards and an optical backplane board, optical slots were used for easy and repeatable insertion and extraction of the boards with a micrometer-scale precision. A 1/spl times/4 850-nm vertical-cavity surface-emitting laser array was used with 2 dBm of output power for the transmitter and a p-i-n photodiode array for the receiver. This paper successfully demonstrates 8 Gb/s of data transmission between the transmitter processing board and the optical backplane board.  相似文献   
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A new analytical method using proton-transfer-reaction mass spectrometry (PTRMS) is described for the determination of trace constituents in human breath. PTRMS is sufficiently sensitive and specific that it does not require preconcentration or separation. At its present stage of development it is capable of detecting trace constituents present in air at the part-per-billion level. These capabilities are illustrated for isoprene, one of the most abundant endogenous hydrocarbons. Our results confirm recent observations of a diurnal level variation associated with sleep or wakefulness; a new finding is that young children have much lower levels of isoprene in breath than adults. To address the metabolic origin of human isoprene, we used PTRMS to analyze expired air for allylic C5 alcohols that have been proposed to be non-enzymatic precursors of isoprene. The lack of correlation between peak breath isoprene and these alcohols suggests that the hydrocarbon is formed by some other mechanism.  相似文献   
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