The Foreign Medical Graduate
A third of the physicians now beginning their career in the U.S. received their education abroad. This substantial proportion reflects underlying flaws in the American system of delivering health care...
Features
Computer-Managed Parts Manufacture
Although a completely automatic factory still lies in the future, important advances have been made in fully automatic systems for the batch manufacture of a variety of complex components...
The Most Primitive Objects in the Solar System
Minerals found in the meteorites known as carbonaceous chondrites represent samples of the solid grains that condensed directly out of the gaseous nebula that gave birth to the sun and the planets...
Chromosomal Proteins and Gene Regulation
The role of the proteins associated,with DNA in the nuclei of higher organisms is beginning to be understood. Apparently the histones keep genes turned off and the nonhistone proteins selectively turn them on...
Dual-Resonance Models of Elementary Particles
In this new theoretical approach the strongly interacting particles classified as hadrons are viewed mathematically as massless strings whose ends move with the speed of light in multidimensional space...
Biological Clocks of the Tidal Zone
Endogenous clocks set to the rhythm of the solar day are known throughout the biological world. Many organisms that live along the shore also have a clock set to the rhythm of the lunar day...
A Carthaginian Fortress in Sardinia
Before her fatal clash with Rome, Carthage dominated the western Mediterranean. A strongpoint on Monte Sirai in Sardinia emerges as part of a network with which she controlled the entire island...
Alfred Wegener and the Hypothesis of Continental Drift
Sixty years ago a German scientist argued that the continents move, and he proposed a history of their migrations. The validity of his theory was not recognized until new evidence emerged in the 1960's...
Departments
50 and 100 Years Ago, February 1975
Science and the Citizen, February 1975
- Letters
Letters to the Editors, February 1975
- Recommended
Books, February 1975
- Mathematical Recreation
Mathematical Games, February 1975
- Amateur Scientist
The Amateur Scientist, February 1975
- Departments
The Authors, February 1975
Bibliography, February 1975
