The largest group of core papers–33–belongs to a specialty area pertaining primarily to b-catenin and its role in carcinogenesis. One of the core papers, a 1998 report from Science describing the interactions of BETA-catenin and other players in the so-called Wnt regulatory pathway in colorectal cancer, is currently #3 in the Biology Top Ten. Other core papers discuss b-catenin mutations in ovarian and prostate cancers.

Among the clusters in the physical-sciences table, theoretical physics accounts for the two top-ranked (i.e., fastest-moving) fields. One of the core papers in the #1 field, a report from Physics Letters B published in 1998, describes efforts to cast the gauge theory known as quantum chromodynamics (QCD) as a string theory. The paper is now #2 in the Physics Top Ten; of this issue, correspondent Simon Mitton discusses this paper in detail. Other papers in the core discuss the particles known as "glueballs," which are described in QCD theory. The #2 theoretical cluster addresses such weighty topics as supergravity, supersymmetry, and Yang-Mills theory.

Theory aside, most of the other physical-sciences fields concern aspects of materials research. These include a research front involving examinations of crystal structure and other characteristics of the sodium vanadate NaV₂0₅. Another cluster is devoted to the relatively new state of matter known as Bose-Einstein condensation (BEC)–the locking together of a macroscopic number of atoms in the same quantum state. One of the core authors in this front is MIT's Wolfgang Ketterle, who last year in these pages discussed implications of this technology, including his development of the first BEC-derived atom laser (see Science Watch, 10[1]:3-4, January/February 1999).

Two specialty areas deal with gallium nitride (GaN) and related materials. The core papers in one of these clusters evaluate field effect transistors (FETs) fashioned from GaN or AlGaN structures. A related front concentrates on GaN films grown via chemical vapor deposition and other means.

Another physical-science cluster points to research on macroporous materials. One foundation paper in this front describes macroporous structures made from samples of titanium, zirconium, and aluminum (see B.T. Holland, et al., Science, 281[5376]:538-40, 24 July 1998). As the authors note, ceramic structures made from such materials could ultimately find application in quantum electronics, photocatalysis, or battery materials.

Chemistry weighs in with a specialty area devoted to b-peptides. This research includes work on polymers with folding properties, or "foldamers," to use the term coined by one of the core authors, Samuel H. Gellman of the University of Wisconsin. Combinatorial chemists and others are hoping to exploit the natural propensity of these peptides to fold into helices and other forms that could serve as the "backbone" of new drug compounds.

Hot research also centers around attempts to clone and copy quantum states. Researchers in this field are investigating logic gates and other structures designed to govern the interaction of quantum bits, or "qubits." Ultra-fast quantum computing and quantum cryptography are just two of the potential applications.

Among the six "superhot" fields, one cluster examines issues surrounding genetically engineered plants. Topics include assessments of harm to the larvae of monarch caterpillars from transgenic pollen, and the containment of resistance to the bacillus thuringiensis (Bt) toxin bioengineered into some strains of corn and other crops. Another hot field entails the "hospitalist" model of inpatient care, a system in which primary-care physicians "hand off" their hospitalized patients to inpatient specialists. Potential advantages include improved physician availability for patients and higher levels of hospital experience and expertise on the part of doctors.