Cuticular hydrocarbons of the screwworm,Cochliomyia hominivorox (Diptera: Calliphoridae)

A novel series of 2,X-dimethylalkanes were isolated and identified. The nonpolar fraction of the surface lipids secreted by the adult (5-day-old) screwworm,Cochliomyia hominivorax, contains over 130 different hydrocarbons comprising normal alkanes (32% of the total hydrocarbon), branched alkanes (53%), and monoalkenes (11%). Branched alkanes included monomethylalkanes with substitution in all possible positions except for 4-methylalkanes, internally branched dimethylalkanes, and 2,X- and 3,X-dimethylalkanes. At emergence, adults of both sexes of the 009 strain have nearly identical gas Chromatographic profiles, which diverge as the insect ages. Irradiation of pharate pupae does not affect the hydrocarbon produced.Mention of a commercial or proprietary product in this paper does not constitute an endorsement of that product by the USDA.     

Clinical implications of research on brief dynamic psychotherapy II. How the therapist helps or hinders therapeutic progress.

In this second of a two-part article, we describe how the therapist's interpretations promote therapeutic progress. Any therapist behavior that is in accord with the patient's plan will be helpful to the patient, but interventions that are at cross purposes with the patient's plan will not be helpful. The implications of the plan concept for brief dynamic therapy are described and contrasted with other key technical, concepts such as transference interpretations, therapeutic alliance, and interpretive activity. The importance of understanding the patient's plan and intervening in accord with it are illustrated in several case vignettes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Parallel construction of SLR (1) and LALR (1) parsers

The generation of an LR parser consists of constructing a parse table, with one row per state (in a push-down automaton), and one column per terminal symbol. Traditionally, this is carried out row by row, with the computation of one row depending (potentially) on all the others. We present a technique for carrying out the lookahead computation of SLR (1) and LALR (1) parsers in a completely parallel fashion. Our technique performs the computation by column, rather than by row. We show that the computation is totally independent for each column, making it ideal for parallelization. The speedup factor of the technique is min (N, T), whereN is the number of processors andT is the number of terminal symbols in the user's grammar.     

DBMS and 4GL Technology: Pressing Questions—and Answers

DBMS technology and product offerings are changing so quickly that few practitioners can stay abreast of current trends. Vendor claims of relational capabilities and the emergence of fourth-generation languages axe not always clear indicators of what DBMS products are best for particular operating environments. In this article, six of the most frequently asked questions about current DBMS and 4GL technology are cleared up for the concerned MIS professional.     

Simulation of complex molecules—Computational requirements for the 1980''s

Improving the understanding of complex molecular systems is an important and interesting use of supercomputers. Computer simulation currently plays, and will continue to play, a vital role in research in this area by acting as a guide to site-specific mutagenesis. This study explains simulations of complex molecules.     

Conversion of Polycrystalline Alumina to Single-Crystal Sapphire by Localized Codoping with Silica

The effect of a localized SiO₂ codoping on the conversion of polycrystalline, MgO-doped Al₂O₃ tubes to single-crystal sapphire was investigated. Codoping with SiO₂ before sintering intentionally triggered abnormal grain growth, which resulted in the full conversion of tube surfaces to single crystal without adversely affecting densification to a almost pore-free, translucent state. The degree of surface conversion was strongly dependent on experimental variables, which included furnace temperature and codoping amount. Surface-converted tubes had excellent physical properties, which included good thermal cycling resistance and optical properties superior to unconverted, polycrystalline Al₂O₃.