L?T3RS Nuclea Safety: S. J. Niemczyk; NAS Exc Protocl: C. B. At#wnsen,P. J. Flory, A. A. Penzias; Paleobiology Caltech: K. M. Towe.. . .......

EDTO L Evolving Patterns of Energy Production and Use . ...................

ARTILES Metal Oxide Chemistry in Solution: Early Transition.Mtl yo ain:V. W. Day ad W. G. Kkmperer .. . . . . . .

Bond Order and Charge lion in Nucleoside: P. A. Freyand R. D. Samn................. ..

Crystaiographic Stnic4ire of the Octameric Histone Core of the Nucleosome at aResolution of 3.3 A: R. W. Burlingame et al..........................

Insertion Mutagenesis of Embryonal Carcinoma Cels by Retroviuses:W. King et al. -

EW ANDC T

RESEARCH MEWS

China Plans Sweeping Reforms in Science ............................. .

Gene Therapy Guidelines Revised ...........................................

Shuttle Encounters a ble.........................................In DIfense of "Star Was" ................................................

Briefing: New Biotechnology Research Progam in Brtain; House OpensBroad Sciece-Policy Hearings; Baby Doe Rgs Set; Panel Examines Costsof Nuclear Warheads; Utilities Look to New Coal Combustion Technology ...

Court Gives CIA Broad Secrecy Rights ......................................

Gregarious Grazers Eat Better .............................-

NSF Commits to Supercomputer ............................................

MQlecuIar Clocks Scrutinized ...............................................

Quantum Theory of Gavity, reviewed by R. D. Sorkin; Atmospheric

531

533

541

546

554

559

561

562

563

564

566

567

568

571

:

tst

t

,.

Electrodynamics, A. D. Richmond; Planetary Rings, A. F. Cook; AFunctional Biology of Sticklebacks, M. A. Bell; Reprints of BooksPreviously Reviewed; Books Received ........ ........................... 572

REPORTS Disturbance and Ecologic Succession in an Upper Ordovician Cobble-DwellingHardground Fauna: M. A. Wilson ........................................ 575

Expression of a Microinjected Porcine Class I Major Histocompatibility ComplexGene in Transgenic Mice: W. I. Frels et al. ....... ....................... 577

Location of Gene for P Subunit of Human T-Cell Receptor at Band 7q35, a RegionProne to Rearrangements in T Cells: M. Isobe et al. ...... ................ 580

Genes for p Chain of Human T-Cell Antigen Receptor Map to Regions ofChromosomal Rearrangement in T Cells: C. C. Morton et al. ..... ......... 582

Template-Directed Synthesis of Novel, Nucleic Acid-Like Structures:A. W. Schwartz and L. E. Orgel ......................................... 585

Epizootic Carcinoma in the Winter Flounder, Pseudopleuronectes americanus:R. A. Murchelano and R. E. Wolke ......... ............................. 587

Comparative Toxinology of Loxosceles reclusa and Corynebacteriumpseudotuberculosis: A. W. Bernheimer, B. J. Campbell, L. J. Forrester...... 590

Ethanol Neurotoxicity: Effects on Neurite Formation and Neurotrophic FactorProduction in Vitro: K. E. Dow and R. J. Riopelle ......................... 591

Characterization of Envelope and Core Structural Gene Products of HTLV-IIIwith Sera from AIDS Patients: W. G. Robey et al. ...... .................. 593

Detection of a Cellular Oncogene in Spontaneous Liver Tumors of B6C3Fl Mice:* T. R. Fox and P. G. Watanabe .......... ................................ 596

Brain Dopamine and Serotonin Receptor Sites Revealed by Digital SubtractionAutoradiography: C. A. Altar et al. ......... ............................ 597

Regenerating Fish Optic Nerves and a Regeneration-Like Response in InjuredOptic Nerves of Adult Rabbits: M. Schwartz et al ........................ 600

Habitat Selection in a Clonal Plant: A. G. Salzman ....... ..................... 603

Amygdalectomy Impairs Crossmodal Association Monkeys: E. A. Murrayand M. Mishkin . ........................................................ 604

Methionine and Leucine Enkephalin in Rat Neurohypophysis: Different Responsesto Osmotic Stimuli and T2 Toxin: N. Zamir et al. ...... ................... 606

COVER

Color-coded image of dopamine (D2)and serotonin (S2) receptors in brain.These receptors are revealed by thebinding of [3H]spiroperidol to a thinhorizontal slice of rat brain. An autora-diograph results from exposing thebrain slice to tritium-sensitive film. Dif-fering gray tones of the developed filmare color-coded, whereby increasingamounts of[H]spitroperidol bindingare represented by black, blue, green,yellow, and red. [ H]Spiroperidol prin-cipally labels S2 receptors in the neo-cortex and D2 receptors in the striatum.See page 597. [Photograph preparedusing the image analysis facility of theLASER Microbeam Program, Univer-sity of California, Irvine. Image prepa-ration and photography by J. N. Joyce]

3 May 1985, Volume 228, Number 4699

AMERICAN ASSOCIATION FOR EvoTHE ADVANCEMENT OF SCIENCE

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SCIE:NCE

lving Patterns of Energy Production and UseLny factors have combined to make profound changes in the energyre. One consequence of the interplay of factors has been to decreaserulnerability of the United States to an interruption of petroleumies. Imports of petroleum and its products into the United States areibout half of what they were in 1978. Another development has been aiing in the ability of OPEC to control the prices of oil. Still anotherquence is to place a lid on the cost of all forms of energy and hence alining force on inflation.,tors contributing to these changes include a substantial increase in thency of energy use which, coupled with conservation practices, hasased demand for petroleum products. The trend toward improvedancy of energy use continues and is likely to continue. Another de-iment has been the installation of large numbers of oil-refining units)le of producing excellent yields of high-value products from heavyoils. This has enhanced the value and marketability of heavy crudes.her development has been increasing discoveries and production of oil:untries outside OPEC, including Brazil, Colombia, Egypt, India,co, Norway, Pakistan, Peru, and the United Kingdom. Another factorsing the demand for oil has been the substitution of other energyes such as natural gas, coal, and nuclear.e enhanced value and marketability of heavy crudes is fostering in-ed production of them and is diminishing the premium paid for light,crudes. The amount of crude oil required to produce a given quantityined products has decreased. Substantial production of petrochemicalsming on stream in Saudi Arabia. This will result in diminished pro-on of them in the United States, thereby lessening somewhat con-lion of natural gas and crude petroleum here. Powerful computerizediysical techniques are being applied to improve reservoir engineering.in turn is also leading to enhanced oil recovery from known fieldsgh use of such procedures as CO2 and steam injection.the United States the discovery rate for natural gas has improved fromit was in the 1970's. At that time about twice as much was consumedyear as was found. In recent years additions to reserves have nearlyced production. The present abundance of producible gas has led to aing of prices and competition with oil for use as a heat source. In turn,al gas in encountering determined competition from electric power fortrial, commercial, and residential markets. One response by the gastry has been to develop more efficient appliances so that gas caniete better with electricity. For example, the thermal efficiency of onetfburners for new home heaters has been increased from about 60 to 90nt.present the use of coal as an energy source is the subject of en-mental concerns about acid rain. But the lower cost per Btu andnopment of improved means of reducing sulfur emissions guaranteeision of the use of coal. Fluidized bed combustion and gasification toice clean intermediate-Btu gas are destined to have substantial futurecations. Industrial use of fluidized beds has been expanding. High-ash,sulfur coal can be burned, and emissions of sulfur oxides and nitrogens can be limited to practically any desired level.increasing share of the world's electricity is being generated at nuclearr stations. Leaders in this development are the United States, France,lapan. In France and Japan, the use of nuclear energy diminishesrts of corresponding amounts of oil. Special circumstances in thed States have led to a poor climate for nuclear energy, but its usenues to expand.-vitably, domestic supplies of oil will diminish, but if current trends ofased energy efficiency and of substitution are maintained, transition tose of other energy sources will proceed relatively smoothly.

-PHILIP H. ABELSON