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This article will present a new soft tissue cephalometric analysis tool. This analysis may be used by the orthodontist and surgeon as an aid in diagnosis and treatment planning. The analysis is a radiographic instrument that was developed directly from the philosophy expressed in Arnett and Bergman ''Facial keys to orthodontic diagnosis and treatment planning, Parts I and II'' (Am J Orthop Dentofacial Orthod 1993; 103:299-312 and 395-411). The novelty of this approach, as with the ''Facial Keys'' articles, is an emphasis on soft tissue facial measurement. (Am J Orthod Dentofacial Orthop 1999;116:239-53)

Previously, we demonstrated that caffeine dose-dependently reinstated extinguished cocaine-taking behavior in rats. In the present study, we determined whether this effect of caffeine would extinguish with repeated exposures. Rats were first trained to self-administer cocaine intravenously. Once reliable self-administration was obtained, the pumps that delivered cocaine were turned off and the lever-pressing behavior was extinguished. Every 4 days the rats were given an injection of caffeine (20.0 mg/kg) and its ability to reinstate responding was measured. Some rats received each of four exposures to caffeine in the previously cocaine-associated environment. Other rats received the first three exposures to caffeine in the home cage and the last exposure to caffeine in the previously cocaine-associated environment. The results indicated that although caffeine was an effective cue for reinstatement of extinguished cocaine taking, the effect was reduced when repeated exposures occurred in the test environment. In addition, when 4 drug-free days were interspersed between self-administration and reinstatement testing, the caffeine effect was greater than when testing was conducted 1 day following the last self-administration session. Thus, extended withdrawal increases the priming effects of caffeine. The results are discussed in terms of the effectiveness of cue exposure as an adjunct to current therapies for cocaine abuse.

Growing interdependence among the world's food markets presents increased trade and investment opportunities for food firms. Although international trade agreements have recently been negotiated which will likely lead to increased food trade, especially among Western nations, revised product standards and technical regulations used in the course of implementing these agreements have potential to create trade barriers that are less obvious. This paper assesses recent developments in food quality and labeling regulations in the European Community (EC) and United States. The regulatory changes taking place in these large trading partners have the potential to result in trade barriers based on meeting technical standards, especially since the reforms are being pursued independently in each country.

Recent MXRF reports have demonstrated marked x-ray flux enhancements over traditional aperturecollimating systems when using a total reflection capillary optic. In the present work, several standard reference materials (SRMs) were examined with a Kevex Omicron MXRF system to compare the elemental sensitivities achieved with an aperture x-ray guide to those obtained with a monolithic polycapillary optic (X-ray Optical Systems). This study is relevant to the MXRF community using commercial aperture-based instruments where trace elemental concentrations in a sample sometimes mandate the need for a higher primary x-ray dose, but the flexibility of incorporating various sized apertures for other samples is still maintained.By scanning the x-ray beam over a nickel/gold knife edge, the capillary focal spot diameter at the time of this work was determined to be ∼400 μm, while a 300 μm aperture provided a beam size of ∼550 μm due to beam divergence past the aperture.

Recent MXRF reports have demonstrated marked x-ray flux enhancements over traditional aperturecollimating systems when using a total reflection capillary optic. In the present work, several standard reference materials (SRMs) were examined with a Kevex Omicron MXRF system to compare the elemental sensitivities achieved with an aperture x-ray guide to those obtained with a monolithic polycapillary optic (X-ray Optical Systems). This study is relevant to the MXRF community using commercial aperture-based instruments where trace elemental concentrations in a sample sometimes mandate the need for a higher primary x-ray dose, but the flexibility of incorporating various sized apertures for other samples is still maintained.By scanning the x-ray beam over a nickel/gold knife edge, the capillary focal spot diameter at the time of this work was determined to be ∼400 μm, while a 300 μm aperture provided a beam size of ∼550 μm due to beam divergence past the aperture.

Summary: TheCatalog of Observations, maintained at the U.S. Naval Observatory as an integral part of theWashington Double Star Catalog, is fast becoming a complete data base with the continued accession of the older data. For the wide pairs contained therein, the principal interest is whether or not they are physical. This report describes the observational history of various series of older observations, and points out what needs to be done to provide a reliable judgement as to the physical relationship of such pairs.

Orbits of the visual binaries RST 321, HU 225, and OL 22 are presented. The orbital elements, ephemerides, the weighted observations and their residuals are given. In each case, a preliminary orbit was subjected to a differential correction, and resulting residuals were examined with a small empirical change made to remove systematic runs in the residuals.