bluuebunny/crossref_metadata_2025 huggingface dataset:
Alcohol: Its Metabolism and Interaction With Nutrients
Authors: Lieber Charles S.
Published: July 2002

In the past, alcoholic liver disease was attributed exclusively to dietary deficiencies, but experimental and judicious clinical studies have now established alcohol's hepatotoxicity. Despite an adequate diet, it can contribute to the entire spectrum of liver diseases, mainly by generating oxidative stress through its microsomal metabolism via cytochrome P4502E1 (CYP2E1). It also interferes with nutrient activation, resulting in changes in nutritional requirements. This is exemplified by methionine, one of the essential amino acids for humans, which needs to be activated to S-adenosylmethionine (SAMe), a process impaired by liver disease. Thus, SAMe rather than methionine is the compound that must be supplemented in the presence of significant liver disease. In baboons, SAMe attenuated mitochondrial lesions and replenished glutathione; it also significantly reduced mortality in patients with Child A or B cirrhosis. Similarly, decreased phosphatidylethanolamine methyltransferase activity is associated with alcoholic liver disease, resulting in phosphatidylcholine depletion and serious consequences for the integrity of membranes. This can be offset by polyenylphosphatidylcholine (PPC), a mixture of polyunsaturated phosphatidylcholines comprising dilinoleoylphosphatidylcholine (DLPC), which has high bioavailability. PPC (and DLPC) opposes major toxic effects of alcohol, with down-regulation of CYP2E1 and reduction of oxidative stress, deactivation of hepatic stellate cells, and increased collagenase activity, which in baboons, results in prevention of ethanol-induced septal fibrosis and cirrhosis. Corresponding clinical trials are ongoing.
TRANSCRIPTIONAL CONTROL OF ADIPOGENESIS
Authors: Rangwala Shamina M. , Lazar Mitchell A.
Published: July 2002

▪ Abstract  The major transcriptional factors involved in the adipogenic process include proteins belonging to the CCAAT/enhancer binding protein family, peroxisome proliferator-activated receptor γ, and adipocyte determination and differentiation dependent factor 1, also known as sterol regulatory element-binding protein 1. This process has been characterized with the aid of cell lines that represent various stages in the path of adipocyte commitment, ranging from pluripotent mesodermal fibroblasts to preadipocytes. Molecular analyses have led to a cascade model for adipogenesis based on timed expression of CCAAT/enhancer-binding proteins and peroxisome proliferator-activated receptor γ. Gene targeting and transgenic-mouse technologies, which allow the manipulation of endogenous genes for these transcription factors, have also contributed to the understanding of adipogenesis. This review aims to integrate this information to gain an understanding of the transcriptional regulation of fat cell formation.
THE ROLE OF C/EBP IN NUTRIENT AND HORMONAL REGULATION OF GENE EXPRESSION
Authors: Roesler William J
Published: July 2002

▪ Abstract  C/EBPs are a family of transcription factors that play important roles in energy metabolism. Although initially thought to be constitutive regulators of transcription, an increasing amount of evidence indicates that their transactivating capacity within the cell can be modulated by nutrients and hormones. There are several mechanisms whereby this occurs. First, hormones/nutrients are known to directly alter the expression of C/EBPs. Second, hormones/nutrients may cause an alteration in the phosphorylation state of C/EBPs, which can affect their DNA-binding activity or transactivating capacity. Third, C/EBPs can function as accessory factors on gene promoters within a hormone response unit, interacting with other transcription factors to enhance the degree of responsiveness to specific hormones. Given their role in regulating genes involved in a wide variety of metabolic events, advancing our understanding of the molecular mechanism of action of C/EBPs will undoubtedly further our appreciation for the role these transcription factors play in both health and disease.
NEW PERSPECTIVES ON FOLATE CATABOLISM
Authors: Suh Jae Rin , Herbig A Katherine , Stover Patrick J
Published: July 2002

▪ Abstract  Folate catabolism has been assumed to result from the nonenzymatic oxidative degradation of labile folate cofactors. Increased rates of folate catabolism and simultaneous folate deficiency occur in several physiological states, including pregnancy, cancer, and when anticonvulsant drugs are used. These studies have introduced the possibility that folate catabolism may be a regulated cellular process that influences intracellular folate concentrations. Recent studies have demonstrated that the iron storage protein ferritin can catabolize folate in vitro and in vivo, and increased heavy-chain ferritin synthesis decreases intracellular folate concentrations independent of exogenous folate levels in cell culture models. Ferritin levels are elevated in most physiological states associated with increased folate catabolism. Therefore, folate catabolism is emerging as an important component in the regulation of intracellular folate concentrations and whole-body folate status.
REGULATION OFNITRICOXIDESYNTHESIS BYDIETARYFACTORS
Authors: Wu Guoyao , Meininger Cynthia J.
Published: July 2002

▪ Abstract  Nitric oxide (NO) is synthesized from L-arginine by NO synthase (NOS). As an endothelium-derived relaxing factor, a mediator of immune responses, a neurotransmitter, a cytotoxic free radical, and a signaling molecule, NO plays crucial roles in virtually every cellular and organ function in the body. The discovery of NO synthesis has unified traditionally diverse research areas in nutrition, physiology, immunology, pathology, and neuroscience. Increasing evidence over the past decade shows that many dietary factors, including protein, amino acids, glucose, fructose, cholesterol, fatty acids, vitamins, minerals, phytoestrogens, ethanol, and polyphenols, are either beneficial to health or contribute to the pathogenesis of chronic diseases partially through modulation of NO production by inducible NOS or constitutive NOS. Although most published studies have focused on only a single nutrient and have generated new and exciting knowledge, future studies are necessary to investigate the interactions of dietary factors on NO synthesis and to define the underlying molecular mechanisms.
BIOTIN INMETABOLISM ANDMOLECULARBIOLOGY
Authors: McMahon Robert J.
Published: July 2002

▪ Abstract  Biotin is a water-soluble vitamin required by all organisms by virtue of its essential role in carboxylation reactions. Although the metabolism and role of biotin in intermediary metabolism are well established, biotin remains one of the most poorly understood water-soluble vitamins in terms of nutritional requirements and responsiveness to physiological and pharmacological states. Significant advances in the understanding of biotin nutriture have been recently accomplished through the description of the kinetics and regulation of biotin transport and improved methods for biotin status assessment. Additionally, the potential role of biotin in the regulation of gene expression has been strengthened through description of altered gene expression during biotin deficiency and through newly described enzymatic activities of the enzyme biotinidase. Given mounting evidence of suboptimum biotin status, a more complete understanding of these aspects of biotin should lead to a greater appreciation of the ways in which biotin aids in the maintenance of health.
TISSUE RENIN-ANGIOTENSIN SYSTEM:A Site of Drug Action?
Authors: Zimmerman and Ben G. , Dunham Earl W.
Published: July 2002

▪ Abstract  In this review, we present background material that provides partial support for a tissue renin-angiotensin system (RAS). Evidence for the existence of this system relied in part the use of drugs, which has entailed using low doses or concentrations of angiotensin-converting enzyme inhibitors, renin inhibitors, and angiotensin antagonists to block the RAS in vascular beds and in isolated arteries or organs.

Other evidence for a tissue RAS has depended upon measurements of the components of the system, i.e. enzymes, substrates, and mRNAs for these proteins. All of these components were first believed to be present in the heart and blood vessels; however, it is now known that renin in the circulating blood derived from the kidney is used for the local synthesis of angiotensins.

The main emphasis of the review is on the renal RAS because it is believed that the local RAS is most prominent in this organ. The renal RAS is probably involved in the long- rather than short-term regulation of renal vascular resistance and maintenance of normal blood pressure through the regulation of sodium reabsorption.
High-Throughput Screening in Drug Metabolism and Pharmacokinetic Support of Drug Discovery
Authors: White Ronald E.
Published: July 2002

The application of rapid methods currently used for screening discovery drug candidates for metabolism and pharmacokinetic characteristics is discussed. General considerations are given for screening in this context, including the criteria for good screens, the use of counterscreens, the proper sequencing of screens, ambiguity in the interpretation of results, strategies for false positives and negatives, and the special difficulties encountered in drug metabolism and pharmacokinetic screening. Detailed descriptions of the present status of screening are provided for absorption potential, blood-brain barrier penetration, inhibition and induction of cytochrome P450, pharmacokinetics, biotransformation, and computer modeling. Although none of the systems currently employed for drug metabolism and pharmacokinetic screening can be considered truly high-throughput, several of them are rapid enough to be a practical part of the screening paradigm for modern, fast-moving discovery programs.
The Regulator of G Protein Signaling Family
Authors: De Vries Luc , Zheng Bin , Fischer Thierry , Elenko Eric , Farquhar Marilyn G.
Published: July 2002

Regulator of G protein signaling (RGS) proteins are responsible for the rapid turnoff of G protein–coupled receptor signaling pathways. The major mechanism whereby RGS proteins negatively regulate G proteins is via the GTPase activating protein activity of their RGS domain. Structural and mutational analyses have characterized the RGS/Gα interaction in detail, explaining the molecular mechanisms of the GTPase activating protein activity of RGS proteins. More than 20 RGS proteins have been isolated, and there are indications that specific RGS proteins regulate specific G protein–coupled receptor pathways. This specificity is probably created by a combination of cell type–specific expression, tissue distribution, intracellular localization, posttranslational modifications, and domains other than the RGS domain that link them to other signaling pathways. In this review we discuss what has been learned so far about the role of RGS proteins in regulating G protein–coupled receptor signaling and point out areas that may be fruitful for future research.
14-3-3 Proteins: Structure, Function, and Regulation
Authors: Fu Haian , Subramanian Romesh R. , Masters Shane C.
Published: July 2002

The 14-3-3 proteins are a family of conserved regulatory molecules expressed in all eukaryotic cells. A striking feature of the 14-3-3 proteins is their ability to bind a multitude of functionally diverse signaling proteins, including kinases, phosphatases, and transmembrane receptors. This plethora of interacting proteins allows 14-3-3 to play important roles in a wide range of vital regulatory processes, such as mitogenic signal transduction, apoptotic cell death, and cell cycle control. In this review, we examine the structural basis for 14-3-3–ligand interactions, proposed functions of 14-3-3 in various signaling pathways, and emerging views of mechanisms that regulate 14-3-3 actions.
Anesthetics and Ion Channels: Molecular Models and Sites of Action
Authors: Yamakura Tomohiro , Bertaccini Edward , Trudell James R , Harris R Adron
Published: July 2002

The mechanisms of general anesthesia in the central nervous system are finally yielding to molecular examination. As a result of research during the past several decades, a group of ligand-gated ion channels have emerged as plausible targets for general anesthetics. Molecular biology techniques have greatly accelerated attempts to classify ligand-gated ion channel sensitivity to general anesthetics, and have identified the sites of receptor subunits critical for anesthetic modulation using chimeric and mutated receptors. The experimental data have facilitated the construction of tenable molecular models for anesthetic binding sites, which in turn allows structural predictions to be tested. In vivo significance of a putative anesthetic target can now be examined by targeted gene manipulations in mice. In this review, we summarize from a molecular perspective recent advances in our understanding of mechanisms of action of general anesthetics on ligand-gated ion channels.
DISSOCIATIVE RECOMBINATION WITH ION STORAGE RINGS
Authors: Larsson Mats
Published: July 2002

▪ Abstract  The development of heavy-ion storage-cooler rings for atomic physics has made it possible to produce high-quality beams of molecular ions that are internally cold. The stored molecular-ion beam is immersed in a cold electron bath, which gives a beam of low divergence and small cross-sectional area. The electron cooler also serves as a target for electron–molecular ion collision experiments. This allows the study of dissociative recombination of cold molecules with respect to cross sections, branching ratios, and angular distibutions at an unprecedented luminosity.
SPECTROSCOPY OF ATOMS AND MOLECULES IN LIQUID HELIUM
Authors: Toennies J. Peter , Vilesov Andrei F.
Published: July 2002

▪ Abstract  Laser ablation of in situ metals has recently made it possible to immerse a large number of different metal atoms and ions and small clusters of metal atoms in liquid helium (He) and thus study their absorption and emission spectra in the visible region. Atoms and molecules are readily picked up by large ([Formula: see text] ≥ 103atoms) He droplets, and their spectra are sensitively detected through the use of either beam depletion following absorption or laser-induced fluorescence. Within the past three years, a wide variety of molecules, ranging from OCS to large organic molecules such as amino acids and a number of van der Waals complexes and even large metal clusters, have been embedded in He droplets and studied either in infrared or in the visible region. These results are discussed here in detail, and the evidence for the effect of superfluidity on the spectral features is reviewed.
Generalized Born Models of Macromolecular Solvation Effects
Authors: Bashford Donald , Case David A.
Published: July 2002

▪ Abstract  It would often be useful in computer simulations to use a simple description of solvation effects, instead of explicitly representing the individual solvent molecules. Continuum dielectric models often work well in describing the thermodynamic aspects of aqueous solvation, and approximations to such models that avoid the need to solve the Poisson equation are attractive because of their computational efficiency. Here we give an overview of one such approximation, the generalized Born model, which is simple and fast enough to be used for molecular dynamics simulations of proteins and nucleic acids. We discuss its strengths and weaknesses, both for its fidelity to the underlying continuum model and for its ability to replace explicit consideration of solvent molecules in macromolecular simulations. We focus particularly on versions of the generalized Born model that have a pair-wise analytical form, and therefore fit most naturally into conventional molecular mechanics calculations.
Reflection Absorption Infrared Spectroscopy and the Structure of Molecular Adsorbates on Metal Surfaces
Authors: Trenary Michael
Published: July 2002

Infrared (IR) spectroscopy is widely used to identify molecular adsorbates that form on metals in the course of surface chemical reactions. Because IR spectroscopy is one of the few surface-sensitive probes that provide molecule-specific information without perturbing the chemisorbed state, there is great interest in extracting as much structural information from the spectra as possible. The various ways IR spectroscopy is used to determine the structure of molecular adsorbates, from strictly qualitative interpretations based on symmetry selection rules to the use of ab initio electronic structure calculations to predict the IR spectrum of a chemisorbed molecule, are reviewed.
EMERGING ROLES FOR CYSTEINE PROTEASES IN HUMAN BIOLOGY
Authors: Chapman Harold A. , Riese Richard J. , Shi Guo-Ping
Published: July 2002

▪ Abstract  Cysteine proteases have traditionally been viewed as lysosomal mediators of terminal protein degradation. However, recent findings refute this limited view and suggest a more expanded role for cysteine proteases in human biology. Several newly discovered members of this enzyme class are regulated proteases with limited tissue expression, which implies specific roles in cellular physiology. These roles appear to include apoptosis, MHC class II immune responses, prohormone processing, and extracellular matrix remodeling important to bone development. The ability of macrophages and other cells to mobilize elastolytic cysteine proteases to their surfaces under specialized conditions may also lead to accelerated collagen and elastin degradation at sites of inflammation in diseases such as atherosclerosis and emphysema. The development of inhibitors of specific cysteine proteases promises to provide new drugs for modifying immunity, osteoporosis, and chronic inflammation.
MOLECULAR MECHANISMS OF PROSTAGLANDIN TRANSPORT
Authors: Schuster Victor L.
Published: July 2002

▪ Abstract  Despite the fact that prostaglandins (PGs) have low intrinsic permeabilities across the plasma membrane, they must cross it twice: first upon release from the cytosol into the blood, and again upon cellular uptake prior to oxidation. Until recently, there were no cloned carriers that transported PGs. PGT is a broadly-expressed, 12-membrane-spanning domain integral membrane protein. When heterologously expressed in HeLa cells or Xenopus oocytes, it catalyzes the rapid, specific, and high-affinity uptake of PGE2, PGF2α, PGD2, 8-iso-PGF2α, and thromboxane B2. Functional studies indicate that PGT transports its substrate as the charged anion. The PGT substrate specificity and inhibitor profile match remarkably well with earlier in situ studies on the metabolic clearance of PGs by rat lung. Because PGT expression is especially high in this tissue, it is likely that PGT mediates the membrane step in PG clearance by the pulmonary circulation. Evidence is presented that PGT may play additional roles in other tissues and that there may be additional PG transporters yet to be identified molecularly.
PREBÖTZINGER COMPLEX AND PACEMAKER NEURONS: Hypothesized Site and Kernel for Respiratory Rhythm Generation
Authors: Rekling Jens C. , Feldman Jack L.
Published: July 2002

▪ Abstract  Identification of the sites and mechanisms underlying the generation of respiratory rhythm is of longstanding interest to physiologists and neurobiologists. Recently, with the development of novel experimental preparations, especially in vitro en bloc and slice preparations of rodent brainstem, progress has been made. In particular, a site in the ventrolateral medulla, the preBötzinger Complex, is hypothesized to contain neuronal circuits generating respiratory rhythm. Lesions or disruption of synaptic transmission within the preBötzinger Complex, either in vivo or in vitro, can abolish respiratory activity. Furthermore, the persistence of respiratory rhythm following interference with postsynaptic inhibition and the subsequent discovery of neurons with endogenous bursting properties within the preBötzinger Complex have led to the hypothesis that rhythmogenesis results from synchronized activity of pacemaker or group-pacemaker neurons.
THE ENTERIC NERVOUS SYSTEM AND REGULATION OF INTESTINAL MOTILITY
Authors: Kunze W. A. A. , Furness J. B.
Published: July 2002

▪ Abstract  The enteric nervous system exerts local control over mixing and propulsive movements in the small intestine. When digestion is in progress, intrinsic primary afferent neurons (IPANs) are activated by the contents of the intestine. The IPANs that have been physiologically characterized are in the intrinsic myenteric ganglia. They are numerous, about 650/mm length of small intestine in the guinea pig, and communicate with each other through slow excitatory transmission to form self-reinforcing assemblies. High proportions of these neurons respond to chemicals in the lumen or to tension in the muscle; physiological stimuli activate assemblies of hundreds or thousands of IPANs. The IPANs make direct connections with muscle motor neurons and with ascending and descending interneurons. The circular muscle contracts as an annulus, about 2–3 mm in minimum oral-to-anal extent in the guinea pig small intestine. The smooth muscle cells form an electrical syncytium that is innervated by about 300 excitatory and 400 inhibitory motor neurons per mm length. The intrinsic nerve circuits that control mixing and propulsion in the small intestine are now known, but it remains to be determined how they are programmed to generate the motility patterns that are observed.
HEAT-SHOCK PROTEINS, MOLECULAR CHAPERONES, AND THE STRESS RESPONSE: Evolutionary and Ecological Physiology
Authors: Feder Martin E. , Hofmann Gretchen E.
Published: July 2002

▪ Abstract  Molecular chaperones, including the heat-shock proteins (Hsps), are a ubiquitous feature of cells in which these proteins cope with stress-induced denaturation of other proteins. Hsps have received the most attention in model organisms undergoing experimental stress in the laboratory, and the function of Hsps at the molecular and cellular level is becoming well understood in this context. A complementary focus is now emerging on the Hsps of both model and nonmodel organisms undergoing stress in nature, on the roles of Hsps in the stress physiology of whole multicellular eukaryotes and the tissues and organs they comprise, and on the ecological and evolutionary correlates of variation in Hsps and the genes that encode them. This focus discloses that (a) expression of Hsps can occur in nature, (b) all species have hsp genes but they vary in the patterns of their expression, (c) Hsp expression can be correlated with resistance to stress, and (d) species' thresholds for Hsp expression are correlated with levels of stress that they naturally undergo. These conclusions are now well established and may require little additional confirmation; many significant questions remain unanswered concerning both the mechanisms of Hsp-mediated stress tolerance at the organismal level and the evolutionary mechanisms that have diversified the hsp genes.
Role of Estrogen Receptor Beta in Estrogen Action
Authors: Pettersson Katarina , Gustafsson Jan-Åke
Published: July 2002

▪ Abstract  There was a time when the classification of sex hormones was simple. Androgens were male and estrogens female. What remains true today is that in young adults androgen levels are higher in males and estrogen levels higher in females. More recently we have learned that estrogens are necessary in males for regulation of male sexual behavior, maintenance of the skeleton and the cardiovascular system, and for normal function of the testis and prostate. The importance of androgen in females was never in doubt, it is after all the precursor of estrogen as the substrate for aromatase, the enzyme that produces estrogen. In addition, the tissue distribution of androgen receptors suggests that androgens themselves are important in the ovary, uterus, breast, and brain.

New information promises to clarify some of the complex issues of the physiological roles of estrogen and the contribution of estrogen to the development of neoplastic diseases in humans. The discovery of the second estrogen receptor, the creation of mutant mice defective in both estrogen receptors and in the aromatase gene, the solution of the structures of the ligand-binding domains of estrogen receptor alpha (ERα) and estrogen receptor beta (ERβ), the finding of novel routes through which estrogen receptors can modulate transcription, and the identification of a man with a bi-allelic disruptive mutation of the ERα gene are but some of the milestones. This review focuses on the mechanistic aspects of signal transduction mediated by ERs and on the physiological consequences of deficiency of estrogen or estrogen receptor in the available mouse models.
Molecular Mechanism of Active Ca2+ Reabsorption in the Distal Nephron
Authors: Hoenderop Joost G. J. , Nilius Bernd , Bindels René J. M.
Published: July 2002

▪ Abstract  The identification of the epithelial Ca2+ channel (ECaC) complements the group of Ca2+ transport proteins including calbindin-D28K, Na+/Ca2+ exchanger and plasma membrane Ca2+-ATPase, which are co-expressed in 1,25(OH)2D3- responsive nephron segments. ECaC constitutes the rate-limiting apical entry step in the process of active transcellular Ca2+ transport and belongs to a superfamily of Ca2+ channels that includes the vanilloid receptor and transient receptor potential channels. This new Ca2+ channel consists of six transmembrane-spanning domains, including a pore-forming hydrophobic stretch between domain 5 and 6. The C- and N-terminal tails contain several conserved regulatory sites, implying that the channel function is modulated by regulatory proteins. The distinctive functional properties of ECaC include a constitutively activated Ca2+ permeability, a high selectivity for Ca2+, hyperpolarization-stimulated and Ca2+-dependent feedback regulation of channel activity, and 1,25(OH)2D3-induced gene activation. This review covers the distinctive properties of this new highly Ca2+-selective channel and highlights the implications for active transcellular Ca2+ reabsorption in health and disease.
Calmodulin as an Ion Channel Subunit
Authors: Saimi Yoshiro , Kung Ching
Published: July 2002

▪ Abstract  A surprising variety of ion channels found in a wide range of species from Homo to Paramecium use calmodulin (CaM) as their constitutive or dissociable Ca2+-sensing subunits. The list includes voltage-gated Ca2+ channels, various Ca2+- or ligand-gated channels, Trp family channels, and even the Ca2+-induced Ca2+ release channels from organelles. Our understanding of CaM chemistry and its relation to enzymes has been instructive in channel research, yet the intense study of CaM regulation of ion channels has also revealed unexpected CaM chemistry. The findings on CaM channel interactions have indicated the existence of secondary interaction sites in addition to the primary CaM-binding peptides and the functional differences between the N- and C-lobes of CaM. The study of CaM in channel biology will figure into our understanding on how this uniform, universal, vital, and ubiquitous Ca2+ decoder coordinates the myriad local and global cell physiological transients.
RECOMBINATION AND THE MULTILOCUS STRUCTURE OF FUNGAL POPULATIONS
Authors: Milgroom Michael G.
Published: July 2002

▪ Abstract  This review examines the relationship between recombination and the multilocus structure of populations. This discussion of population structure is based on the pattern of genetic variation within populations, especially the frequencies of multilocus genotypes, which can be used for making inferences about recombination. Three questions are addressed: Is population structure consistent with a random mating hypothesis? Is there evidence for recombination? How frequently does recombination occur?
EFFECTS OFPLANTS ONNEMATODECOMMUNITYSTRUCTURE
Authors: Yeates GW
Published: July 2002

▪ Abstract  Plant-related inputs provide the resources for nematode communities. Sampling of nematode communities must be on appropriate temporal and spatial scales. Size, feeding types, food or host specificity, and chronology allow over 200 nematode species to coexist in a district. Relationships between nematode functional groups and ecological processes regulating decomposition processes have been found in field experiments. Pulse-labeling experiments have shown root-feeding nematodes to increase the flow of carbon from roots to soil microbial biomass. Soil texture is related to suitability for cropping and affects nematode communities through crop-specific infestations. Nematode diversity tends to be greatest in ecosystems with least disturbance, and bacterial-feeding nematodes make the greatest contribution to the decomposer food web in more intensively managed ecosystems. Indices of the nematode fauna reflect changes in the nematode community; these changes reflect soil and ecological processes. Understanding the role of nematodes in these processes is the key to understanding of the relationship between plants and soil nematode communities.
Advances in Plant Health Management in the Twentieth Century
Authors: Cook R. James
Published: July 2002

▪ Abstract  Plant health management is the science and practice of understanding and overcoming the succession of biotic and abiotic factors that limit plants from achieving their full genetic potential as crops, ornamentals, timber trees, or other uses. Although practiced as long as agriculture itself, as a science-based concept, plant heath management is even younger than integrated pest management (IPM), and includes and builds upon but is not a replacement for IPM. Probably the greatest collection of success stories for plant health management is the number of diseases managed by cleaning up the planting material. The record for root health management is more mixed, with the loss or phase-out of soil fumigants, and practices such as crop rotation and clean tillage being replaced with more intensive cropping and less or no tillage. Perhaps the greatest scientific and technical advances for plant health management have come from the work aimed at management of the pathogens, pests, and other hazards that arrive by air. Flor's work on flax rust, which produced the gene-for-gene model, is possibly the most significant contribution of plant pathology to the life sciences in the twentieth century. Research aimed at the management of foliar pathogens is also the basis for modern theory on epidemiology, population biology, aerobiology, and disease prediction and decision-support systems. Even IPM arose mainly in response to the need to protect crops from pests that arrive by air. If the definition of biological control includes the plant induced or genetically modified to defend itself, as it should, then biological control has been the most significant approach to plant health management during the twentieth century and promises through modern biotechnology to be even more significant in the twenty-first century. Rather than “reducing losses,” the advances are discussed here within the simple framework of achieving the attainable yield by increasing the actual and/or affordable and hence the average yield. Each of these four benchmark yields, as well as the absolute yield for crops, and their significance to the goals and achievements of plant health management are defined. Plant health management is a moving target, which I discuss metaphorically like an American football game, where one team is science and technology and the other is nature, where the S & T team is only beginning to know nature's rules while playing itself with the three sets of rules written to, respectively, satisfy the laws of economics, protect the environment, and gain social acceptance.
MODELS OF GOVERNMENT FORMATION
Authors: Laver Michael
Published: July 2002

▪ Abstract  This review deals with the making and breaking of governments in “minority legislatures” in which no political party controls a majority of seats. It looks at both a priori and empirical approaches to analyzing government formation, at the application of both cooperative and noncooperative game-theoretic models, and at the impact of both office-seeking and policy-seeking assumptions about the motivations of politicians. Substantive themes covered include the partisan composition of both minority and majority cabinets, the allocation of cabinet portfolios between parties, and the duration of cabinets in minority legislatures. The way forward in this field is identified in terms of the need for more dynamic models that see government formation as a complex system within the broader context of party competition as a whole, and for models that take fundamental account of intraparty politics in their description of the strategic behavior of political parties.
FEDERALISM, FEDERAL POLITICAL SYSTEMS, AND FEDERATIONS
Authors: Watts Ronald L.
Published: July 2002

▪ Abstract  Political events in various parts of the world during the past decade have attracted new attention to the strengths and weaknesses of federal solutions as a means of resolving political problems. Conceptual distinctions have been drawn between “federalism” as a normative term, “federal political systems” as a descriptive term referring to a broad genus of federal arrangements, and “federation” as a particular species within that genus. The extensive literature on the design and operation of federal systems is reviewed, with particular attention to asymmetry among constituent units, degrees of noncentralization, financial relationships, the impact of federative institutions and the courts, and the development of multi-tiered federal systems. Federal processes illustrated by patterns of formation and evolution, the significance of the increasingly global economy, intergovernmental relations, the impact of cultural, ethnic and national diversities, and the pathology of federal systems are also considered.
CONTENDING THEORIES OF CONTENTIOUS POLITICS AND THE STRUCTURE-ACTION PROBLEM OF SOCIAL ORDER
Authors: Lichbach Mark I.
Published: July 2002

▪ Abstract  To understand protest in America, one must understand protest and one must understand America. More generally, the study of resistance against authority may adopt two foci: authority (structure) and resistance (action). The leading practitioners of the structuralist approach to contentious politics—McAdam, Tarrow, and Tilly—have jointly systematized their ideas. This synthesis, which I call Synthetic Political Opportunity Theory (SPOT), exerts domination and hegemony over the field. Its upstart rational action challenger is the Collective Action Research Program (CARP). I outline the basic presuppositions of SPOT and CARP and describe their different approaches to the structure-action problem of constituting social order. I then explore the potential of a CARP-SPOT consortium. I conclude that synergisms of the perspectives are possible but that trade-offs are inevitable: strong on action, weak on structure and vice versa; strong on resistance, weak on authority and vice versa; and strong on protest, weak on America and vice versa. Hence, we need creative confrontations, which should include well-defined combinations rather than grand syntheses, of rationalist and structuralist approaches to contentious politics.
Post-Soviet Politics
Authors: Laitin David D.
Published: July 2002

Since the collapse of the Soviet Union in 1991, the area specialty of Soviet Politics has been transformed. Research on six themes is reviewed: state and revolution, democratization, federalism, economic growth, international relations, and institutional legacies reflecting the communist past. The review finds that post-Soviet research speaks directly to current trends in political science, and the findings of this research should impel generalists to re-specify their theories. A recommendation is offered that the study of post-Soviet politics should push political science away from a notion of institutionalization and in the direction of identifying institutional equilibria.
Constitutional Political Economy: On the Possibility of Combining Rational Choice Theory and Comparative Politics
Authors: Norman Schofield
Published: July 2002

Rational choice theory has typically used either noncooperative game theory or cooperative, social choice theory to model elections, coalition bargaining, the prisoner's dilemma, and so on. This essay concentrates on the ideas of William Riker and Douglass North, both of whom, in very different ways, studied events of the past in an attempt to understand constitutional or institutional transformations. The key notion presented here is the “belief cascade,” a change in the understanding of the members of a society when they face a quandary. This idea is used to critique simple vote-maximizing models of elections, derived from Downs' earlier conception of party competition. Inferences are drawn on the possible applications of rational choice theory to the study of constitutional political economy in order to provide some insight into the differences between democratic polities.
Political Trust and Trustworthiness
Authors: Levi Margaret , Stoker Laura
Published: July 2002

After addressing the meaning of “trust” and “trustworthiness,” we review survey-based research on citizens' judgments of trust in governments and politicians, and historical and comparative case study research on political trust and government trustworthiness. We first provide an overview of research in these two traditions, and then take up four topics in more detail: (a) political trust and political participation; (b) political trust, public opinion, and the vote; (c) political trust, trustworthy government, and citizen compliance; and (d) political trust, social trust, and cooperation. We conclude with a discussion of fruitful directions for future research.
POLITICS, POLITICALSCIENCE,ANDURBANGOVERNANCE: A Literature and a Legacy
Authors: Murphy Russell D.
Published: July 2002

▪ Abstract  Politics has not always fared well in the political science literature on the cities, at least not in the United States. Since the mid-nineteenth century, a substantial literature has either decried or discounted the role of politics in urban governance. Much of the early literature, written before and just after the creation of the American Political Science Association in 1903, urged politics be banished and administration privileged as a way to remedy “one conspicuous failure of the United States … the government of cities.” Subsequent literature reinstated politics—though some claimed elected officials were simply agents of special interests or upper-class elites. The prevailing view today is that political leadership is an important, independent factor in the governing equation, although it is arguable that of late national and state administrators have been empowered at the expense of local self-rule—thus approximating, albeit by different means, the system envisioned by early municipal reformers.
OFWAVES ANDRIPPLES: Democracy and Political Change in Africa in the 1990s
Authors: Gibson Clark C.
Published: July 2002

▪ Abstract  This chapter reviews the literature concerned with explaining recent political change in Africa. After recounting some of the political transformations on the continent, it explores the economic and political factors most often invoked by scholars to account for these changes. The chapter concludes with a call for more comparative work, as well as more precise measures, models, and tests.
VERBAL LEARNING AND MEMORY: Does the Modal Model Still Work?
Authors: Healy Alice F. , McNamara Danielle S.
Published: July 2002

▪ Abstract  This chapter focuses on recent research concerning verbal learning and memory. A prominent guiding framework for research on this topic over the past three decades has been the modal model of memory, which postulates distinct sensory, primary, and secondary memory stores. Although this model continues to be popular, it has fostered much debate concerning its validity and specifically the need for its three separate memory stores. The chapter reviews research supporting and research contradicting the modal model, as well as alternative modern frameworks. Extensions of the modal model are discussed, including the search of associative memory model, the perturbation model, precategorical acoustic store, and permastore. Alternative approaches are discussed including working memory, conceptual short-term memory, long-term working memory, short-term activation and attention, processing streams, the feature model, distinctiveness, and procedural reinstatement.
HEALTH PSYCHOLOGY: What is an Unhealthy Environment and How Does It Get Under the Skin?
Authors: Taylor Shelley E. , Repetti Rena L. , Seeman Teresa
Published: July 2002

▪ Abstract  This review explores the role of environments in creating chronic and acute health disorders. A general framework for studying the nesting of social environments and the multiple pathways by which environmental factors may adversely affect health is offered. Treating socioeconomic status (SES) and race as contextual factors, we examine characteristics of the environments of community, work, family, and peer interaction for predictors of positive and adverse health outcomes across the lifespan. We consider chronic stress/allostatic load, mental distress, coping skills and resources, and health habits and behaviors as classes of mechanisms that address how unhealthy environments get “under the skin,” to create health disorders. Across multiple environments, unhealthy environments are those that threaten safety, that undermine the creation of social ties, and that are conflictual, abusive, or violent. A healthy environment, in contrast, provides safety, opportunities for social integration, and the ability to predict and/or control aspects of that environment.
MEMORY-BASED LANGUAGE PROCESSING: Psycholinguistic Research in the 1990s
Authors: McKoon Gail , Ratcliff Roger
Published: July 2002

▪ Abstract  There are two main domains of research in psycholinguistics: sentence processing, concerned with how the syntactic structures of sentences are computed, and text processing, concerned with how the meanings of larger units of text are understood. In recent sentence processing research, a new and controversial theme is that syntactic computations may rely heavily on statistical information about the relative frequencies with which different syntactic structures occur in the language. In text processing, recent research has focused on what information the words and ideas of a text evoke from long- term memory quickly, passively, and at low processing cost. Research in both domains has begun to use the information that can be obtained from large corpora of naturally occurring texts.
COGNITIVE DEVELOPMENT: Children's Knowledge About the Mind
Authors: Flavell John H.
Published: July 2002

▪ Abstract  This chapter reviews theory and research on the development of children's knowledge about the mental world, focusing especially on work done during the past 15 years under the rubric of theory-of-mind development. The three principal approaches to explaining this development—theory theory, modular theory, and simulation theory—are described first. Next comes a description of infant precursors or protoforms of theory-of-mind knowledge in infancy, including a beginning awareness of the intentionality and goal-directedness of human actions. This discussion is followed by a summary of the postinfancy development of children's understanding of visual perception, attention, desires, emotions, intentions, beliefs, knowledge, pretense, and thinking. Briefly considered next are intracultural, intercultural, and interspecies differences in theory-of-mind development. The chapter then concludes with some guesses about the future of the field.
Consumer Research: In Search of Identity
Authors: Simonson Itamar , Carmon Ziv , Dhar Ravi , Drolet Aimee , Nowlis Stephen M.
Published: July 2002

▪ Abstract  Although the consumer research field has made great progress over the past 30 years with respect to the scope, quality, and quantity of research, there are still significant disagreements about what consumer research is, what its objectives are, and how it should differ from related disciplines. As a result, the field appears to be rather fragmented and even divided on some fundamental issues. In this review we first examine the original vision for the field and its limitations. In the second section we explore the consequences of the ambiguity about the domain and identity of consumer research and the multidisciplinary influences on the field. In particular, we review key trends and “camps” in consumer research, which represent complementary and, in some cases, conflicting views regarding the main topics of investigation and how research is conducted. This review is based in part on systematic analyses of articles that have been published in the leading consumer research journals over the past 30 years. Finally, in the third section we revisit the question of what might differentiate the field from related disciplines, as well as the role of theory testing, studies of substantive phenomena, and relevance in consumer research.
Nature and Operation of Attitudes
Authors: Ajzen Icek
Published: July 2002

▪ Abstract  This survey of attitude theory and research published between 1996 and 1999 covers the conceptualization of attitude, attitude formation and activation, attitude structure and function, and the attitude-behavior relation. Research regarding the expectancy-value model of attitude is considered, as are the roles of accessible beliefs and affective versus cognitive processes in the formation of attitudes. The survey reviews research on attitude strength and its antecedents and consequences, and covers progress made on the assessment of attitudinal ambivalence and its effects. Also considered is research on automatic attitude activation, attitude functions, and the relation of attitudes to broader values. A large number of studies dealt with the relation between attitudes and behavior. Research revealing additional moderators of this relation is reviewed, as are theory and research on the link between intentions and actions. Most work in this context was devoted to issues raised by the theories of reasoned action and planned behavior. The present review highlights the nature of perceived behavioral control, the relative importance of attitudes and subjective norms, the utility of adding more predictors, and the roles of prior behavior and habit.
Intergroup Bias
Authors: Hewstone Miles , Rubin Mark , Willis Hazel
Published: July 2002

▪ Abstract  This chapter reviews the extensive literature on bias in favor of in-groups at the expense of out-groups. We focus on five issues and identify areas for future research: (a) measurement and conceptual issues (especially in-group favoritism vs. out-group derogation, and explicit vs. implicit measures of bias); (b) modern theories of bias highlighting motivational explanations (social identity, optimal distinctiveness, uncertainty reduction, social dominance, terror management); (c) key moderators of bias, especially those that exacerbate bias (identification, group size, status and power, threat, positive-negative asymmetry, personality and individual differences); (d) reduction of bias (individual vs. intergroup approaches, especially models of social categorization); and (e) the link between intergroup bias and more corrosive forms of social hostility.
Clinical Assessment
Authors: Wood James M. , Garb Howard N. , Lilienfeld Scott O. , Nezworski M. Teresa
Published: July 2002

▪ Abstract  Are clinical psychologists' assessment practices cost-effective? Are they scientifically sound? Are they fair and unbiased? Financial pressures from managed care interests, recent developments in the law, and multicultural issues are forcing the profession to confront these hard questions regarding accountability. Our review discusses the important changes that have begun to alter the field of personality assessment and describes recent research on clinical judgment and its implications for the future. We conclude that clinical psychology can adapt to future conditions by developing assessment strategies that are economical, scientifically sound, and culturally sensitive.