Optofluidic characterization of marine algae using a microflow cytometer

The effects of global warming, pollution in river effluents, and changing ocean currents can be studied by characterizing variations in phytoplankton populations. We demonstrate the design and fabrication of a Microflow Cytometer for characterization of phytoplankton. Guided by chevron-shaped grooves on the top and bottom of a microfluidic channel, two symmetric sheath streams wrap around a central sample stream and hydrodynamically focus it in the center of the channel. The lasers are carefully chosen to provide excitation light close to the maximum absorbance wavelengths for the intrinsic fluorophores chlorophyll and phycoerythrin, and the excitation light is coupled to the flow cytometer through the use of an optical fiber. Fluorescence and light scatter are collected using two multimode optical fibers placed at 90-degree angles with respect to the excitation fiber. Light emerging from these collection fibers is directed through optical bandpass filters into photomultiplier tubes. The cytometer measured the optical and side scatter properties of Karenia b., Synechococcus sp., Pseudo-Nitzchia, and Alexandrium. The effect of the sheath-to-sample flow-rate ratio on the light scatter and fluorescence of these marine microorganisms was investigated. Reducing the sample flow rate from 200 μL/min to 10 μL/min produced a more tightly focused sample stream and less heterogeneous signals.     

非凡而又敏捷的家蝇

一只家蝇能把一件事做得出奇得好,那就是:飞行。最近,一组英国科学家宣布,普通的家蝇是地球上最天才的空气动力学家,它比任何的鸟、蝙蝠或蜜蜂都要高明许多。一只家蝇能在一秒钟之内做6个旋转动作;它能在空中旋停;向上直飞、向下直飞、向后直飞;它能翻筋斗;降落在天花板上;而且     

Large-Scale Patterns of Entertainment Gratifications in Linguistic Content of U.S. Films

We count words in film subtitle files in an attempt to reveal morally relevant patterns of linguistic content. We argue that function words (e.g., pronouns, prepositions, conjunctions) should be positively associated with thought-provoking narrative forms. To test this hypothesis, we associate function words to aggregate measures of film viewership and appraisals. Results suggest that function words are negatively associated with measures of viewership but positively associated with appraisals. As such, our finding is consistent with the idea that function words are more likely to occur in narrative forms that audiences value more than they actually consume. We relate this finding to past research, which has shown the same pattern for hedonic versus meaningful entertainment gratifications. Discussion centers on implications for recent theorizing in this area.     

What Cognitive Benefits Does an Activity-Based Reading Strategy Afford Young Native American Readers?

The authors conducted 2 experiments with children from a reservation community. In Experiment 1, 45 third-grade children were randomly assigned to the following reading strategies: (a) “reread,” in which participants read each sentence of a story and then reread it; (b) “observe,” in which participants read sentences and then observed an experimenter move manipulatives as directed by the story; and (c) “activity,” in which participants read sentences and then moved manipulatives as directed by the story. In Experiment 2, 40 second-grade children were randomly assigned to either the reread or activity strategy. In both experiments, activity participants remembered more story content than did reread participants. In Experiment 1, the authors identified no memory differences between observe and activity strategies. When imagery instructions replaced the original strategies, Experiment 1 third-grade activity (and observe) participants recalled more story content than did reread participants, but Experiment 2 second-grade activity participants did not. The authors discuss the instructional benefits of activity-based reading strategies, along with developmental implications.     

Prevention Through Consultation: A Model to Guide Future Developments in the Field of School Psychology

The Invitational Conference on the Future of School Psychology held at Indiana University in 2002 had implications for consultation. It addressed projected shortages in school psychologists that provide a rationale for service delivery models integrating consultation and prevention. The conference discussed the need for effective work with children, families, and professionals from diverse cultures; success in fostering productive home-school connections; optimal and ethical use of rapidly changing technologies; and the use of empirical evidence to inform practice. This article presents a model of consultation and prevention informed by recent research in positive psychology as well as public health models. This model is discussed in the context of these and other important developments in the field of school psychology.     

Learning from a Computer Tutor with Natural Language Capabilities

CIRCSIM-Tutor is a computer tutor designed to carry out a natural language dialogue with a medical student. Its domain is the baroreceptor reflex, the part of the cardiovascular system that is responsible for maintaining a constant blood pressure. CIRCSIM-Tutor’s interaction with students is modeled after the tutoring behavior of two experienced human tutors. The effectiveness of CIRCSIM-Tutor has been tested by 50 first-year medical students. Using a pre-test/post-test paradigm we have demonstrated that significant learning occurs during a 1 hr interaction with the program. Students were also surveyed and indicated considerable satisfaction with the program.     

Writing and Publishing

John Tebbel's A History of Book Publishing in the United States: Volume III--The Golden Age Between Two Wars, 1920-1940 (New York: R.R. Bowker, 1978---$32.50)

Anne Lyon Haight and Chandler Grannis' Banned Books: 387 BC to 1978 AD (New York: Bowker, 1978---$13.95)

Bruce Joel Hillman and Judith Ann Beraha, eds. 1979 Writer's Market (Cincinnati, Ohio: Writer's Digest Books, 1978---$14.95)

Doris Ricker Marston's A Guide to Writing History (Cincinnati, Ohio: Writer's Digest, 1976---$8.50)

Girls Series Books: A Checklist of Hardback Books Published 1900-1975 (Children's Literature Research Collections, University of Minnesota Libraries, Minneapolis, Minn. 55455---price not given, but about $7.50, paper)     

Radio and Television History

ROD SERUNG: THE DREAMS AND NIGHTMARES OF LIFE INTHE TWILIGHT ZONE by Joel Engel (Chicago: Contemporary Books, 1990—$18.95, ISBN 0-8092-4538-8,368 pp.)

THE PIED PIPERS OF ROCK 'n ROLL: RADIO DEEJAYS OF THE 50s AND 60s by Wes Smith (Marietta, GA: Longstreet Press, 1989—$16.95, ISBN 0-929264-69-X, 300 pp.)

GUNSMOKE.A COMPLETE HISTORY by SuzAnne Barabas and Gabor Barabas (Jefferson, NC: McFarland & Co., 1990—$45.00, ISBN 0-89950-418-3, 832 pp.) is just that—a detailed narrative and then episode guide to both the radio (1952-61)

THE COMPLETE ACTORS TELEVISIONCREDITS, 1948-1988, VOLUME I: ACTORS by James Robert Parish and Vincent Terrace (Metuchen, NJ: Scarecrow Press, 1989—$59.50, ISBN 0-8108-2204-0, 560 pp.)

THE CHILDREN'S HOUR: RADIO PROGRAMS FOR CHILDREN, 1929-1956 by Marilyn Lawrence Boemer (Metuchen, NJ: Scarecrow Press, 1989—$25.00, ISBN 0-8108-2270-9, 230 pp.)

I REMEMBER TELEVISION: A MEMOIR by Ira Skutch (Metuchen, NJ: Scarecrow Press, 1989—$29.50, ISBN 0-8108-2271-7, 273 pp.)

LIVE TELEVISION: THE GOLDEN AGEOF1946-1958 IN NEW YORK by Frank Sturcken (McFarland & Co., P.O. Box 611, Jefferson, NC 28640—$29.95, ISBN 0-89950-523-6, 178 pp.)