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In recent years, the topic of "Suburban Gridlock" has emerged as one of the most significant transportation problems in the United States (Cervero, 1985). As population deconcentrates from central cities to suburban rings, and increasingly to the peripheries of those rings, employment has tended to follow. High-technology manufacturing, and associated research and development, have traditionally sought suburban locations, out-of-town shopping centers have consolidated their position, rivalling and often exceeding the sales and employment volumes of downtown stores, campus office parks have become larger and denser, producing mini-downtowns in the new suburbs. The result has been that traditional, radial, suburb-to-city commute patterns have been overlain and increasingly overwhelmed by a new pattern of non-radial, suburb-to-suburb trips.

High-speed rail is the most visible form of new technology accompanying and enhancing the transformation to an information-based economy, and is likely to have the greatest spatial development effects of any of these technologies. This report studies the development effects of high-speed rail stations on behalf of the California Department of Transportation (Caltrans), which is currently considering the use of high-speed rail in California.Since high-speed rail is a relatively new technology and is in use in only a few countries, the development effects of high-speed rail stations are somewhat difficult to discern and categorize. Nonetheless, a review of the literature on its development effects in Japan, France, and Germany, and observation of stations in the latter two countries, reveals significant development effects at the regional, urban, and station levels. These include changes to the following: population and employment growth rates; ridership; business behavior; real estate values and activity; business and employment location; and residential location. A review of related rail systems, heavy and commuter rail, reveals similar effects and opportunities for value capture.The development effects of high-speed rail stations are most clearly associated with a strong regional economy and good links with other transportation modes, especially rail links to the local city center and public sector support of development. The presence of these factors can help provide the formation of significant development activity around stations catering to the information-exchange sector, such as offices and hotels, the stimulation of retail activities in the area, and increases in overall land value of approximately 20 percent. At the regional and urban levels, concentrations of information-exchange sector employment and centers of higher education are associated with above-average employment and population growth rates, as well as access to high-speed rail.In California, high-speed rail would reinforce existing population and employment patterns and future growth trends. In order to fully exploit station development opportunities and ensure ridership, the agency responsible for developing a high-speed rail system in California must take an active role in station area development and coordinate its activities with local transportation agencies.

This is one of a series of reports now being produced as the first output of our study of the potential for a high-speed passenger train service in California. Each report deals with a specific high-speed train technology; it attempts an evaluation, standardized as far as available data permit, of its technical and economic viability.Specifically, each report assesses the particular high-speed technology against a number of criteria:1. Technical Performance: configuration of roadbed in terms of gradients, curvature, and construction cost; power sources; capacity and speed; capacity to integrate with existing transportation facilities.2. Economic performance: traffic levels; revenues; financial appraisal and overall cost-benefit analysis; level of public subsidy required, if any.3. Resource consumption and environmental performance: type and amount of energy required; impact on non-renewable resources; environmental impact, including emissions, noise, visual intrusion and effect on local communities.The present series includes five studies. Two companion studies, on British Rail's InterCity 125 and 225 services and on Tilting Trains (the Italian Pendolino and the Swedish X-2000 service), will follow shortly. Thereafter, a systematic comparative analysis will be published.The CalSpeed study will continue with preliminary route alignments, also to be produced shortly, followed by market assessments, to be completed in Fall 1992. These will bring to a close the present phase of work, which will be the subject of an overall report also to be completed in Fall 1992.We gratefully acknowledge the support provided by the U.S. Department of Transportation and the California State Department of Transportation (Caltrans) through the University of California Transportation Center. Of course, any errors of fact or interpretation should be assigned to us and not our sponsors.

Magnetic levitation is the first truly new transportation technology in one hundred years and comes at a time when advances in transportation are sorely needed. The German Transrapid magnetic levitation train is the first commercially available system to use this technology. Based on technology that originated in the United States, the Transrapid system has been under development for approximately 15 years in Germany. During the last decade a number of serious proposals have been made for its use in the United States and Germany. However, to date, non have left the planning stage and all remain speculative at best. This is a function of the high level of risk associated with such a new technology, which has yet to prove itself in commercial operations, despite holding great promise for high levels of service.

Rates of return to active substance use after addiction treatment tend to be high; participation in 12-step fellowships (e.g., Alcoholics Anonymous) reduces relapse rates but many clients do not attend or attend for a short period only. This quasi-experimental study uses repeated measurement to explore the role of presence/absence of on-site 12-step meetings during treatment on post-treatment outcomes. Polysubstance-dependent clients (N = 219) recruited at a program with and one without 12-step on-site, were followed for one year post-treatment. On-site 12-step enhanced 12-step attendance, especially during treatment, and predicted continuous abstinence for the post-treatment year. Holding 12-step meetings on-site is a low-cost strategy that programs should consider to foster post-treatment remission maintenance. (Contains 3 tables.)

We narrowed the spectral bandwidth of our 2 W broad-area laser to 8 [+ or -] 1 GHz with a coarse tunability of 12 nm centered near 790 nm in an external cavity. Our passively stabilized external cavity was designed for use with high-power semiconductor lasers. The cavity length and mount are modular with a fixed pivot point so that the optical elements can be changed to access a broad frequency spectrum and enable multiple applications. The bandwidth was observed to be dependent on the multimode transverse structure of the laser. OCIS codes: 140.3600, 140.2010, 140.2020, 140.3460.

Some concurrent use of alcohol and prescribed drugs is inevitable. Health care professionals must be aware of the interactions between alcohol and such drugs to guide them in prescribing and [...]

Alcoholics who stop drinking commonly experience anxiety, both in the immediate period of withdrawal from alcohol and later on. Some persons have chronic anxiety, while others have acute attacks of panic. Studies have indicated that anxiety may be more common in alcoholics than in the population as a whole. Alcohol dependence may develop in individuals who find that alcohol reduces their anxiety or panic. Some experts have suggested that treating alcoholics with anti-anxiety drugs may promote the abuse of these drugs, leading to controversy about this mode of treatment. The cases of three alcoholics with diagnosed panic disorder who were successfully treated with clonazepam are discussed. Clonazepam is a long-acting benzodiazepine that is effective in treating panic disorder. Patient 1, a 34-year-old married white man, found that his panic attacks and social phobia (including fear of crowds and public places) were greatly alleviated by clonazepam. The second patient, a 38-year-old married black man, reported feeling much more comfortable in social situations while on clonazepam, after a long history of avoiding such situations due to frequent panic and chronic anxiety. He later resumed drinking and the panic attacks returned, but were less frequent than before. Patient 3, a 64-year-old white married man, experienced complete relief from his chronic anxiety and panic attacks with clonazepam; he also remained sober for a year (the duration of follow-up) with the help of Alcoholics Anonymous. These patients appear to be part of a subgroup of alcoholics who can be safely treated for anxiety and panic disorder with benzodiazepines; they all apparently developed alcohol dependence because they found it reduced or interrupted panic attacks. The results also suggest that benzodiazepine therapy may not always lead sober alcoholics to return to drinking. (Consumer Summary produced by Reliance Medical Information, Inc.), INTRODUCTION Alcoholic patients frequently complain of anxiety, both in the acute withdrawal phase and after several weeks postwithdrawal. Complaints are highly varied and range from pervasive, chronic anxiety to discrete [...]

The generation of reactive oxygen species using nonequilibrium atmospheric pressure plasma jet devices has been a subject of recent interest due to their ability to generate localized concentrations from a compact source. To date, such studies with plasma jet devices have primarily utilized radio-frequency excitation. In this work, we characterize ozone generation in a kHz-pulsed capillary dielectric barrier discharge configuration comprised of an active discharge plasma jet operating in ambient air that is externally grounded. The plasma jet flow gas was composed of helium with an admixture of up to 5% oxygen. A unipolar voltage pulse train with a 20 ns pulse risetime was used to drive the discharge at repetition rates between 2-25 kHz. Using UVLED absorption spectroscopy centered at 255 nm near the Hartley-band absorption peak, ozone was detected over 1 cm from the capillary axis. We observed roughly linear scaling of ozone production with increasing pulse repetition rate up to a 'turnover frequency,' beyond which ozone production steadily dropped and discharge current and 777 nm O(5P→5S°) emission sharply increased. The turnover in ozone production occurred at higher pulse frequencies with increasing flow rate and decreasing applied voltage with a common energy density of 55 mJ/cm3 supplied to the discharge. The limiting energy density and peak ozone production both increased with increasing O2 admixture. The power dissipated in the discharge was obtained from circuit current and voltage measurements using a modified parallel plate dielectric barrier discharge circuit model and the volume-averaged ozone concentration was derived from a 2D ozone absorption measurement. From these measurements, the volume-averaged efficiency of ozone production was calculated to be 23 g/kWh at conditions for peak ozone production of 41 mg/h at 11 kV applied voltage, 3% O2, 2 l/min flow rate, and 13 kHz pulse repetition rate, with 1.79 W dissipated in the discharge. [ABSTRACT FROM AUTHOR]

A hairpin resonator was used to measure the electron number density in the afterglow of a nitrogen glow discharge (p=0.25–0.75 Torr). Electron number densities were measured using a time-dependent approach similar to the approach used by Spencer et al. [J. Phys. D 20, 923 (1987)]. The decay time of the electron number density was used to determine the electron temperature in the afterglow, assuming a loss of electrons via ambipolar diffusion to the walls. The electron temperature in the near afterglow remained between 0.4 and 0.6 eV, depending on pressure. This confirms the work by Guerra et al. [IEEE Trans. Plasma. Sci. 31, 542 (2003)], who demonstrated experimentally and numerically that the electron temperature stays significantly above room temperature via superelastic collisions with highly vibrationally excited ground state molecules and metastables, such as A 3Σu+. [ABSTRACT FROM AUTHOR]

Temporally resolved images acquired using a 5-ns gated intensified charge-coupled device camera show the dynamical behavior of a plasma jet emanating from the end of a dielectric capillary operating at atmospheric pressure. Broadband emission and filtered emission from excited Ar, He, [N.sub.2] and [N.sup.+.sub.2] species were acquired. The properties of the highly localized so-called 'plasma bullets' that make up the plasma jet strongly resemble the properties of cathode-directed streamers in positive corona discharges. Index Terms--Atmospheric pressure plasma jet (APPJ), dielectric capillary, streamers, time-resolved optical imaging.