The head and foot of Pelmatohydra oligactis,pall., as unipotent systems

Summary The head and foot ofPelmatohydra oligactis function in regeneration as unipotent systems. The exact extent of the unipotent tissue immediately posterior to the tentacles and anterior to the foot is not determined in these experiments. The intermediate tissue is pluripotent.The potentiality for head formation is stronger at the oral end and decreases towards the aboral end as the potentiality for foot formation increases.In these grafting experiments the stock has no influence over the graft which retains its individuality.Preliminary account im Akademischen Anzeiger, Wien, No. 24. 22. November 1923: Mitteilungen aus der Biologischen Versuchsanstalt der Akademie der Wissenschaften in Wien, Zoologische Abteilung, Vorstand:H. Przibram. Nr. 113. Kopf und Fuß des Süßwasserpolypen,Pelmatohydra oligactis Pall., als unipotente Systeme vonD. R. R. Burt.     

Can interaction coefficients be determined from cencus data?

Summary The method of estimating interactions proposed independently by Pimm and Schoener is studied using field data from the community of rodents which lives in the arid, rocky habitats of Israel. One important problem the method addresses is how to remove the effects of habitat heterogeneity on the estimate. We tried six different variations of the analysis scheme outlined by Crowell and Pimm, and found their results qualitatively inconsistent. This was especially true when we compared the results produced from separate habitat variables with those produced from the principal components of the habitat variation.Another problem, this one not previously addressed, is great variation in the average abundance of the different species. We discovered that the ratio of the average abundances of two species is the best predictor of the value of their coefficients of interaction. Common species appear to have weak influence on rare ones; rare ones appear to have strong influence on common ones. The statistical mechanism which produces this relationship is clear, indicating that the relationship is an artifact.     

Network-Free Inference of Knockout Effects in Yeast

Perturbation experiments, in which a certain gene is knocked out and the expression levels of other genes are observed, constitute a fundamental step in uncovering the intricate wiring diagrams in the living cell and elucidating the causal roles of genes in signaling and regulation. Here we present a novel framework for analyzing large cohorts of gene knockout experiments and their genome-wide effects on expression levels. We devise clustering-like algorithms that identify groups of genes that behave similarly with respect to the knockout data, and utilize them to predict knockout effects and to annotate physical interactions between proteins as inhibiting or activating. Differing from previous approaches, our prediction approach does not depend on physical network information; the latter is used only for the annotation task. Consequently, it is both more efficient and of wider applicability than previous methods. We evaluate our approach using a large scale collection of gene knockout experiments in yeast, comparing it to the state-of-the-art SPINE algorithm. In cross validation tests, our algorithm exhibits superior prediction accuracy, while at the same time increasing the coverage by over 25-fold. Significant coverage gains are obtained also in the annotation of the physical network.     

Epitopia: a web-server for predicting B-cell epitopes

Background  

Detecting candidate B-cell epitopes in a protein is a basic and fundamental step in many immunological applications. Due to the impracticality of experimental approaches to systematically scan the entire protein, a computational tool that predicts the most probable epitope regions is desirable.     

In vitro selection for salt tolerance in crop plants: Theoretical and practical considerations

Summary In recent years attempts have been made to supplement traditional breeding for the production of salt-tolerant plants with variability existing in cell culture. The potential causes suggested as an explanation for the limited success of the in vitro approach include: a) lack, or loss during selection, of regeneration capability; b) the development of epigenetically adapted cells; c) lack of correlation between the mechanisms of tolerance operating in cultured cells and mechanisms that operate in cells in the intact plant; and d) multigenicity of salt tolerance. The recent successful production of healthy, fertile, and genetically stable salt-tolerant regenerants from cells obtained from highly morphogenic explants which are selected early in culture (using one-step or short-term strategies) for salt tolerance, together with the demonstration that salt-sensitive plants can become tolerant by mutations in one or few genes, suggest that some of the potential limitations can be overcome and that some of them may not exist at all.     

Reviews

The Family Album. A film by Alan Berliner. 16mm, 55min, b/w. Distributed by Filmmakers Library, Inc.

Beyond Words—Images from America's Concentration Camps. By Deborah Gesensway and Mindy Roseman. 1987, 176 pages, illustrated. Ithaca: Cornell University Press. Price: cloth $24.95.

The Lau (Granada Television “Disappearing World” Series). A film by Leslie Woodhead, producer‐director; Jon Woods, camera; Ray French, sound; Kimball Horton, editor; David Wasson, researcher; and Pierre Maranda, anthropological consultant. 1987, video, color, 52 minutes. Dialogues: Lau. Subtitles: English. Narration: English. Distributed by Granada TV International, Suite 3468, 1221 Avenue of the Americas, New York, NY 10020, tele. 212–242–2363. Price: on application.

Men's Lives: The Surfmen and Baymen of the South Fork. By Peter Matthiessen. 1986, New York: Random House. Price: hardcover $29.95; softcover $7.95 (Vintage Press); limited edition $200 (University of Washington Press, Seattle).

In Her Own Time. A film by Lynne Littman with Barbara Myerhoff. 1986, 16mm, color, 60 minutes. Distributed by Direct Cinema, Ltd., P.O. Box 69589, Los Angeles, CA 90060, tele. 213–652–8000. Price: 16mm—purchase $895, rental $100; video—purchase $350, rental $50 (prices quoted are for educational institutions only).

The Miracle of Intervale Avenue. A film by Irving Rappaport, producer; Ken Howard, director; and Jack Kugelmaas, associate producer. 1983, 16mm, color, 65 minutes. Catalog #430. Distributed by Ergo Media, Inc., P.O. Box 2037, Teaneck, NJ 07666, tele. 201–692–0404.

Some Babies Die. A film by Martyn Landon Down. Australia, 16mm, color, 54 minutes. Distributed by The University of California Extension Media Center, 2176 Shattuck Avenue, Berkeley, CA 94704, tele. 415–642–1340. Price: 16mm—purchase $850, rental $60; video—purchase $450, rental $60.

El Sebou’: The Egyptian Birth Ritual. A film by Fadwa El Guindi; produced by El Nil Research Project; co‐sponsored by the Office of Folklife, Smithsonian Institution. 1986, 16mm, color, 27 minutes. Distributed by El Nil Research Project, 1157 Beverwil Drive, Los Angeles, CA 90035, tele. 213–553–5645. Price: 16mm—purchase $570, rental $70; video—purchase $370. Screenings: Society for Visual Anthropology (1987 Award for Excellence); 1987 Margaret Mead Film Festival; Royal Anthropological Institute (1988 Commendation).

The Making of El Sebou‘

Classified People. Yolande Zauberman, director; produced by OBSESSION/INA/CNC/ FR3‐TOULOUSE; Dewald Aukema, camera; Tony Bensusan, sound; Jean‐François Naudon, editor. 1987, 16mm, color, 53 minutes. Distributed by TELEMONDIS, 15, rue Mesnil, 75016, Paris, tele. 47–27–03–84, telex: 649 078 TELMOND. In U.S., distributed by Filmmaker's Library, 124 E. 40th Street, New York, NY 10016, tele. 212–355–6545. Price: 16mm—rental only $150; video (½″ or ¾″)—purchase $75, rental $75. Screenings: Festival of Women's Films at Créteil (Prix de Jury); Festival of Young Directors at Belfort (Prix de Publique); Bilan du Film Ethnographique 1988 (Prix Nanook/Grand Prix); 1988 Cinéma du Réel; 1987 Margaret Mead Film Festival; U.S. Public Television.

To Cross the Border: An interview with Filmmaker Yolande Zauberman, Paris, May 1988.