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A standard interface between simulation programs and systems analysis software.

A simple interface between simulation programs and systems analytical software is proposed. This interface is designed to facilitate linkage of environmental simulation programs with systems analytical software and thus can contribute to remedying the deficiency in applying systems analytical techniques to environmental modelling studies. The proposed concept, consisting of a text file interface combined with a batch mode simulation program call, is independent of model structure, operating system and programming language. It is open for implementation by academic and commercial simulation and systems analytical software developers and is very simple to implement. Its practicability is demonstrated by implementations for three environmental simulation packages (AQUASIM, SWAT and LEACHM) and two systems analytical program packages (UNCSIM, SUFI). The properties listed above and the demonstration of the ease of implementation of the approach are prerequisites for the stimulation of a widespread implementation of the proposed interface that would be beneficial for the dissemination of systems analytical techniques in the environmental and engineering sciences. Furthermore, such a development could stimulate the transfer of systems analytical techniques between different fields of application.

Environment↗

The geographical accessibility of hospitals to the aged: a geographic information systems analysis within Illinois.

OBJECTIVE: This article uses geographic information systems and their related tools to empirically measure and display the geographic accessibility of the aged population to hospital facilities within Illinois. DATA SOURCES AND STUDY SETTING: Geographic accessibility of Illinois' aged population is measured from each of the state's 10,796 census block groups to the state's 214 hospital facilities. Block group demographic compositions and centroids are obtained from 1990 census files. Hospital coordinates are obtained by the authors. STUDY DESIGN: Of five alternative measures of accessibility considered, empirical estimates are obtained for two: choice set and minimum distance. Access to both general hospitals and the subset having specialized geriatric facilities is measured with special attention to differences in accessibility between the aged within metropolitan statistical areas (MSAs) and those outside MSAs. Cumulative accessibility distributions and their summary statistics provide a basis of comparison among subgroups. DATA COLLECTION AND EXTRACTION: Geographic information systems (GIS) and their related tools are used as a means of efficiently capturing, organizing, storing, and retrieving the required data. Hospitals and census block groups are geocoded to specific locations in the database, and aspatial attributes are assigned to the hospitals and block groups. The GIS database is queried to produce shaded isarithm and point distribution maps that show the location of hospitals relative to surrounding aged populations. CONCLUSION: The vast majority of Illinois' aged population is within close proximity to hospital facilities. Eighty percent (1,147,504 persons) of the aged in Illinois are within 4.8 miles (7.7 km) of a hospital and 11.6 miles (18.7 km) of two hospitals. However, geographic accessibility differences between the aged living in MSAs and those living outside MSAs to hospitals offering geriatric services are substantial; but there is no evidence that the aged's geographical accessibility to hospitals is less favorable than that of the general population. Detailed accessibility measures permitted by geographic information system technology call into question the continued use of crude empirical accessibility measures.

Aged↗

The BaI X2Sigma+ and B2Sigma+ Electronic States Through B2Sigma+-X2Sigma+ and C2Pi-X2Sigma+ Band Systems Analysis.

The near-infrared spectrum of the B2Sigma+-X2Sigma+ band system of the BaI molecule, obtained from the chemiluminescent reaction Ba + I2 and also by laser-induced fluorescence (LIF), was recorded by using Fourier transform spectroscopy (FTS). The LIF spectra were obtained by using a Ti:sapphire single-mode laser excitation. Resolved rotational data, originating from 32 vibrational levels (0 </= v </= 31) in the X2Sigma+ state and from 24 vibrational levels (0 </= v </= 19, and v = 21, 22, 23, 26) in the B2Sigma+ state, were used in the final analysis. Previously recorded data for the C2Pi-X2Sigma+ band system (with Deltav = 0), taken from C. A. Leach, A. A. Tsekouras, and R. N. Zare, J. Mol. Spectrosc. 153, 59-72 (1992), were added to the present work data field. Accurate and improved molecular constants for the X2Sigma+, B2Sigma+, and C2Pi states were derived from a simultaneous treatment of the whole data set. Copyright 1999 Academic Press.

Journal Article↗

Exploiting the enzymatic recognition of an unnatural base pair to develop a universal genetic analysis system.

BACKGROUND: With the invention of the DNA chip, genome-wide analysis is now a reality. Unfortunately, solid-phase detection systems such as the DNA chip suffer from a narrow range in quantification and sensitivity. Today the best methodology for sensitive, wide dynamic range quantification and genotyping of nucleic acids is real-time PCR. However, multiplexed real-time PCR technologies require complicated and costly design and manufacturing of separate detection probes for each new target. METHODS: We developed a novel real-time PCR technology that uses universal energy transfer probes constructed from An Expanded Genetic Information System (AEGIS) for both quantification and genotyping analyses. RESULTS: RNA quantification by reverse transcription-PCR was linear over four orders of magnitude for the simultaneous analysis of beta-actin messenger RNA and 18S ribosomal RNA. A single trial validation study of 176 previously genotyped clinical specimens was performed by endpoint analysis for factor V Leiden and prothrombin 20210A mutation detection. There was concordance for 173 samples between the genotyping results from Invader tests and the AEGIS universal energy transfer probe system for both factor V Leiden and prothrombin G20210A. Two prothrombin and one factor V sample gave indeterminate results (no calls). CONCLUSION: The AEGIS universal probe system allows for rapid development of PCR assays for nucleic acid quantification and genotyping.

Actins↗