Subscribe
Subscribe
MY AMERICAN SCIENTIST
LOG IN! REGISTER!
SEARCH
 
Logo IMG
HOME > PAST ISSUE

On the Cover

January-February 2007 Volume 95, Number 1

The simple act of freezing water vapor produces snowflakes with fernlike branches, multilayered faceted plates and a myriad of other shapes. The temperature and humidity ranges required to produce these various ice gems have been mapped out for 75 years, but it remains largely unknown just why certain conditions lead to specific structures and why minor changes in temperature can radically alter the resulting snowflake forms. ...


FEATURE ARTICLES

Gauging Earthquake Hazards with Precariously Balanced Rocks *

James Brune, Matthew Purvance, Abdolrasool Anooshehpoor

Finding easily toppled boulders that are still standing provides a way to test models of seismic hazard


Why We Develop Food Allergies

Per Brandtzaeg

Coached by breast milk and good bacteria, the immune system strives to learn the difference between food and pathogens before the first morsel crosses our lips


When Averages Hide Individual Differences in Clinical Trials *

David Kent, Rodney Hayward

Analyzing the results of clinical trials to expose individual patients' risks might help doctors make better treatment decisions


The Mysterious Origin of the Sweet Apple

Barrie Juniper

On its way to a grocery counter near you, this delicious fruit traversed continents and mastered coevolution


The Formation of Snow Crystals

Kenneth Libbrecht

Subtle molecular processes govern the growth of a remarkable variety of elaborate ice structures


* access restricted to members and subscribers


SCIENTISTS’ BOOKSHELF

A Paradise of Choice?

Brian Hayes

A review of The Long Tail: Why the Future of Business Is Selling Less of More, by Chris Anderson. Anderson maintains that it is now easier to sell one copy each of a million things than to sell a million copies of one thing. But has the sales curve really changed its shape to reflect a wider spectrum of interests?

See all book reviews for this issue.


DEPARTMENTS

COMPUTING SCIENCE

Foolproof

Brian Hayes

Mathematical proof is foolproof, it seems, only in the absence of fools

MACROSCOPE

Volcano Myths and Rituals

John Dvorak

Differing views of the universe add to the challenge of dealing with natural disasters

SIGHTINGS

Expressing Genes

Felice Frankel

Analyzing and visualizing gene expression during development

MARGINALIA

Blow-up

Roald Hoffmann

Images from the nanoworld challenge viewers' thinking

ENGINEERING

Long Crossings *

Henry Petroski

Driving from Sweden to Denmark is an uplifting experience

SCIENCE OBSERVER

Getting All Revved Up

David Schneider

Large energy-storage flywheels are being tested for some surprising applications

Persistently Clean?

Christopher R. Brodie

Antimicrobials accumulate in the municipal sludge used to fertilize crops

In the News

LETTERS TO THE EDITORS

The Eagle Has Landed

Ratted Out

The Role of Algae

FROM THE PRESIDENT

SIGMA XI TODAY (PDF)


Subscribe to American Scientist