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Several letters to the editor are presented in response to articles in previous issues, including an article on homosexuality in the September 8, 1975 issue, the earthquake in San Francisco, California in the September 1 issue, and the school openings in the September 15 issue.

The traditional approach to geologic mapping consists of sketching, taking orientation and thickness measurements with compass and tape, and noting positions of features on topographic maps or photos. These methods are time consuming, often difficult to realize in rough terrain, and poorly constrain lateral variations in sedimentary facies in relatively flat lying strata. We describe a case study that captures the three-dimensional architecture of sandstone bodies and key geological surfaces such as stratigraphic boundaries and faults using digital capture techniques. The Ferron sandstone in Utah is a superbly exposed ancient delta deposit that provides an improtant outcrop analog to fluvio-deltaic subsurface reservoirs. It has been the focus of many traditional outcrop studies, but here we use a methodology (“cybermapping”) based on GPS with offsets from a continuous ranging mode reflectorless laser rangefinder (“laser sketch”) for collection and analysis of basic stratigraphic and structural data in a relatively remote area. We also show hos this data can be analyzed and visualized in three dimensions. The study area was mapped in two days, which included hiking several kilometers into the area. One-the-fly and rapid static post processing of GPS surveying was used for positioning the reflectorness laser rangefinders; 60,000 points were acquired mapping sedimentological and structural features, terrain, and control points. The resultant quantitative 3D model of the geology and terrain allowed robust geometric visualization and analyses. © 2001 John Wiley & Sons, Inc.

Smart management seeks flexible manufacturing The increasing influence of Pacific Rim countries and the impending developments in Europe set for 1992 will leave US manufacturers out in the cold if [...]

Many species of interferon have been identified and purified from human leukocytes, and genes for these interferons have been cloned in bacterial systems. However, it is still unclear as to how the expression of each of the different leukocyte interferons is regulated and how they function in the natural system. In preparation for a study of the in vivorole of individual leukocyte interferons we have developed a rapid and convenient high-performance liquid chromatographic method for purifying several species of human leukocyte interferon. Interferon produced by the induction of leukocytes (obtained from buffy coats of normal donors) with Sendai virus and partially purified by ethanol fractionation was further purified by size-exclusion high-performance liquid chromatography (on two Waters,I-125 columns) in 0.05 Msodium phosphate buffer, pH 6, containing 0.2 Msodium chloride. The flow-rate was 2 ml/min and interferon activity (antiviral) was eluted from the columns in less than 15 min in a single fraction well resolved from high-molecular-weight contaminants. This material was then purified by reversed-phase high-performance liquid chromatography on a wide-pore diphenyl column (Whatman Protesil 300) with a gradient system at pH 2.4, consisting of (A) 0.05 MKH2PO4—methoxyethanol (19:1) and (B) 1-propanol—methoxyethanol (19:1). Several peaks of interferon activity were distinguishable in this system. Analysis of the pooled peaks of interferon activity by SDS polyacrylamide gel electrophoresis confirmed the presence of more than one form of leukocyte interferon. The specific activity of the purified leukocyte interferers was ca.108units/mg protein.

We report the cloning of PER6, a gene essential for peroxisome biogenesis in the methylotrophic yeast Pichia pastoris. The PER6 sequence predicts that its product Per6p is a 52-kDa polypeptide with the cysteine-rich C3HC4 motif. Per6p has significant overall sequence similarity with the human peroxisome assembly factor PAF-1, a protein that is defective in certain patients suffering from the peroxisomal disorder Zellweger syndrome, and with car1, a protein required for peroxisome biogenesis and caryogamy in the filamentous fungus Podospora anserina. In addition, the C3HC4 motif and two of the three membrane-spanning segments predicted for Per6p align with the C3HC4 motifs and the two membrane-spanning segments predicted for PAF-1 and car1. Like PAF-1, Per6p is a peroxisomal integral membrane protein. In methanol- or oleic acid-induced cells of per6 mutants, morphologically recognizable peroxisomes are absent. Instead, peroxisomal remnants are observed. In addition, peroxisomal matrix proteins are synthesized but located in the cytosol. The similarities between Per6p and PAF-1 in amino acid sequence and biochemical properties, and between mutants defective in their respective genes, suggest that Per6p is the putative yeast homolog of PAF-1.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Discusses the things the National Association of Realtors is doing to reach out to real estate brokers in their different practices. Establishment of commercial overlay boards at the state and local levels; NAR's sponsorship of the Appraisal Foundation in Washington, D.C.; NAR's purchase of Real Estate Buyer's Agent Council; Establishment of an advisory council of large brokerage companies.

Offers advice concerning the selection of a residential broker. Comparison between an agent and a broker; Asking relatives and friends about the related experiences; Asking for the opinion of others regarding the service from the broker; Importance of attending open houses and watching brokers in action; Looking for the broker's concern on meeting the client's needs.