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Many different demands can be made of intrusion detection systems. An important requirement is that an intrusion detection system be effective; that is, it should detect a substantial percentage of intrusions into the supervised system, while still keeping the false alarm rate at an acceptable level. This article demonstrates that, for a reasonable set of assumptions, the false alarm rate is the limiting factor for the performance of an intrusion detection system. This is due to the base-rate fallacy phenomenon, that in order to achieve substantial values of the Bayesian detection rate P͑IntrusionAlarm͒, we have to achieve a (perhaps in some cases unattainably) low false alarm rate. A selection of reports of intrusion detection performance are reviewed, and the conclusion is reached that there are indications that at least some types of intrusion detection have far to go before they can attain such low false alarm rates.

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Background: Exposure to environmental tobacco smoke (ETS) has important public health implications. The results of the first European multi-centre study that measured ETS exposure in a range of public places (transport, educational settings, and leisure facilities such as bars and restaurants) are presented. Method: Nicotine vapour phase was measured using ETS passive samplers containing a filter treated with sodium bisulfate. Results: Bars and discos are the places with the highest concentrations of nicotine from ETS, median ranging from 19 to 122 mg/m 3 . Restaurants had the next highest values. Concentrations of nicotine generally range from 0.1-5 mg/m 3 in airports, and from 0.5-10 mg/m 3 in train stations. Nicotine was also found in schools and universities, yet schools tended to have the lowest concentrations compared to all the other public places sampled. In hospitals levels were generally below 5 mg/m 3 . Conclusions: Although there is some variability between cities, this study shows that tobacco smoke is present in most of the studied public places. The study also showed that in areas where smoking is prohibited, concentrations of nicotine are lower than in areas where smoking is allowed but they are not zero. The results of this study indicate that policies should be implemented that would effectively reduce levels of tobacco smoke in public areas.

Abstract.In this report we demonstrate an increase in the steady-state level of bone sialoprotein (BSP) mRNA in rat calvaria and a rat osteosarcoma cell line (ROS 17/2.8) after treatment with the synthetic glucocorticoid, dexamethasone. In contrast, 1.25-dthydroxyvitamin D3 reduced the amount of BSP mRNA in calvaria and inhibited the dexamethasone induction in ROS 17/2.8 cells. The increase in BSP mRNA is most likely due to an increase in the transcriptional rate. The stability of mRNA was unchanged after dexamethasone treatment with a half-life of r~5 h. Nuclear transcription experiments with nuclei isolated from ROS 17/2.8 cells showed an increased BSP mRNA synthesis in cells treated with dexamethasone.ONE sialoprotein (BSP), ~ which we previously called sialoprotein II, is an acidic glycoprotein associated with the mineral matrix in bone and teeth (2, 3). The protein contains ",,50% carbohydrate of which 15 % is sialic acid (3). Furthermore, some 30% of the serine residues are phosphorylated and contribute to the acidity of BSP. The amino acid sequence of BSP, deduced from eDNA, predicts a 34-kD protein core with predominantly glutamic acid and glycine residues, which constitute one third of all amino acid residues (10). The protein contains several clusters of up to 10 consecutive glutamic acid residues. These negatively charged domains, together with the sialic acid residues and phosphate groups, are presumably responsible for the strong interaction with hydroxyapatite.BSP promotes the attachment and spreading of rat osteosarcoma cells (ROS 17/12.8) as well as primary bovine chondrocytes in cell-binding experiments using plastic dishes coated with the protein (11,12). This cell binding is apparently mediated by an RGD-containing region in BSP, which is homologous to the cell-binding domain in vitronectin (10). The BSP receptor is an integrin indistinguishable from the vitronectin receptor on the surface of ROS 17/2.8 cells (11).BSP shares some structural features with another bone protein, osteopontin (OPN) (9). The OPN sequence contains a stretch of nine consecutive aspartic acid residues comparable to the glutamic acid clusters in BSP. OPN also contains a cell-binding RGD sequence which promotes attachment of cells in a similar way as BSP (9). The synthesis of OPN in bone cells is regulated by steroid hormones. It has been shown that 1,25-dihydroxyvitamin D3 (vit D3) increases the level of OPN mRNA, whereas the synthetic glucocorticoid, dexamethasone, reduces the steady-state level of OPN mRNA (15).It is well established that steroid hormones have pronounced influence on the metabolism of bone. Some of these 1. Abbre~ations used in this paper: BSP, bone siaioprotein; DRB, 5,6-dichloro-1-/~-ribofuranosyl benzimidazole; OPN, osteopontin; ROS, rat osteosarcoma; vit D3, 1,25-dihydroxyvitamin D3. effects may be exerted via effects on cells, possibly mediated via cell-binding proteins. The present study, therefore, was undertaken to determine the effects of different steroid hormones on the biosynthesis of two ...

Refers to the following text of the Journal: 2005;31(1):0

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We have theoretically investigated the high frequency properties of a carbon-nanotube-based three-terminal nanoelectromechanical relay. The intrinsic mechanical frequency of the relay is in the GHz regime, and the electromechanical coupling shows a non-linear resonant behaviour in this frequency range. We discuss how these resonances may be detected and show that the resonance frequencies can be tuned by the bias voltage. Also, we show that the influence of external electromagnetic fields on the relay is negligible at all frequencies.