bluuebunny/crossref_metadata_2025 huggingface dataset:
Proton-Conducting Oxides
Authors: Kreuer K.D.
Published: July 2003

▪ Abstract  The structural and chemical parameters determining the formation and mobility of protonic defects in oxides are discussed, and the paramount role of high-molar volume, coordination numbers, and symmetry are emphasized. Symmetry also relates to the structural and chemical matching of the acceptor dopant. Y-doped BaZrO3-based oxides are demonstrated to combine high stability with high proton conductivity that exceeds the conductivity of the best oxide ion conductors at temperatures below about 700°C. The unfavorably high grain boundary impedances and brittleness of ceramics have been reduced by forming solid solutions with small amounts of BaCeO3, and an initial fuel cell test has demonstrated that proton-conducting electrolytes based on Y-doped BaZrO3provide alternatives for separator materials in solid oxide fuel cells (SOFCs). These materials have the potential to operate at lower temperatures compared with those of conventional SOFCs, and the appearance of chemical water diffusion across the electrolyte at typical operation temperatures (T = 500–800°C) allows the use of dry methane as a fuel.
Supported Electrolyte Thin Film Synthesis of Solid Oxide Fuel Cells
Authors: De Jonghe Lutgard C. , Jacobson Craig P. , Visco Steven J.
Published: July 2003

▪ Abstract  Solid oxide fuel cells operating at temperatures below 800°C require the use of supported thin film solid electrolytes. A variety of processing methods are reviewed that can deliver electrolyte films with satisfactory performance. These include vapor phase, sol-gel, and powder methods such as colloidal deposition. An important consideration is that a number of these processing methods may not meet the low cost required by commercialization. The most cost-effective methods are considered to be simple powder methods combined with co-firing.
Low-Energy Electron Microscopy of Surface Phase Transitions
Authors: Hannon James B. , Tromp Ruud M.
Published: July 2003

▪ Abstract  The use of low-energy electron microscopy (LEEM) to study reversible surface phase transitions is reviewed. Representative experiments are described that highlight the key advantages of LEEM: the ability to image surfaces in situ, at elevated temperature, with good spatial and temporal resolution. With these capabilities, the evolution of individual surface features—domains, facets, islands, steps, etc.—can be measured. Real-time and real-space imaging make LEEM a powerful tool for characterizing the thermodynamics and kinetics that govern surface phase transformations.
Intestinal Pseudo-Obstruction Syndrome
Authors: Anuras Sinn
Published: July 2003

Intestinal pseudo-obstruction is a syndrome of many causes. Attempts must be made to determine the cause and the extent of the involvement of the gastrointestinal tract in each patient, because they will dictate the method of treatment for that patient. Family history must be taken from all primary chronic intestinal pseudo-obstruction patients. If it is positive, genetic counseling and proper medical management can be given to newly identified cases in the family.
Pathogenesis of Acute Pancreatitis
Authors: Steer Michael L. , Meldolesi Jacopo
Published: July 2003

Recent studies using experimental models of acute pancreatitis suggest that events blocking evoked secretion of digestive enzymes from acinar cells may play an important role in the pathogenesis of this disease. Under these conditions, digestive enzymes become co-localized with lysosomal hydrolases within large intracellular vacuoles, where activation of trypsin by the lysosomal enzyme cathepsin B could initiate the cascade activation of the other pancreatic zymogens. Development of acute pancreatitis might, therefore, be initiated by events occurring within acinar cells rather than in the ductal system or the interstitium of the gland.
Antiphospholipid Anti-Bodies—Autoantibodies with a Difference
Authors: Harris E. Nigel , Asherson Ronald A. , Hughes Graham R. V.
Published: July 2003

Antiphospholipid antibodies may be detected by solid phase anticardiolipin antibody tests, the lupus anticoagulant test, or standard tests for syphilis (STS). The occurrence of these antibodies has been associated with venous or arterial thrombosis, fetal loss, and possibly thrombocytopenia. Other suggested features that may be associated with these antibodies include livedo reticularis, migraine, chorea, and heart valve lesions. Uncontrolled studies of small numbers of affected women with recurrent fetal loss suggest that prednisone and aspirin therapy during pregnancy may improve pregnancy outcome. Anticoagulant therapy is recommended for patients with thrombosis for as long as antiphospholipid antibodies persist.
Mediators of Ischemic Renal Injury
Authors: Bonventre Joseph V.
Published: July 2003

Acute renal failure is a serious consequence of renal ischemia. The diagnosis carries an associated high mortality rate. When blood flow to the kidneys is inadequate to supply metabolic demands, a number of pathophysiological changes occur that ultimately result in cell death and tissue dysfunction, characterized by a marked reduction in glomerular filtration rate and associated accumulation of systemic toxins and disorders of fluid and electrolyte metabolism. In this chapter we review the factors that have been implicated as mediators of the renal tissue damage associated with ischemia and reperfusion.
Anticoagulants During Pregnancy
Authors: Ginsberg Jeffrey S. , Hirsh Jack
Published: July 2003

Anticoagulant therapy during pregnancy is problematic because both heparin and oral anticoagulants can potentially produce adverse maternal and fetal effects. Reviewing the relevant literature makes it clear that heparin is safer for the fetus than are oral anticoagulants. For the prophylaxis and treatment of venous thromboembolic disease in pregnant patients, heparin is the preferred anticoagulant because its efficacy and safety are established. However, because the efficacy of heparin in preventing systemic embolism in patients with prosthetic heart valves is not established, either adjusted-dose heparin or a combination of heparin and oral anticoagulants can be used.
Autologous Bone Marrow Transplantation
Authors: Santos George W. , Yeager Andrew M. , Jones Richard J.
Published: July 2003

Autologous bone marrow transplantation in the acute leukemias and lymphomas offers potentially curative treatment in patients who do not have a histocompatible, allogeneic donor. Results of marrow autografting in the lymphomas are especially encouraging, with disease-free survivals of 50-60% in patients who have failed primary and secondary treatment regimens. In the acute leukemias, one may expect 20-40% relapse-free survival after autologous marrow transplantation. We feel that ex vivo treatment (“purging”) is necessary to eradicate occult tumor cells from autologous remission marrow in hematological malignancies, but this remains a controversial issue to some investigators. Preliminary studies of autologous bone marrow transplantation are promising in multiple myeloma and certain childhood tumors, and autografting is currently being explored in the treatment of other solid tumors such as adenocarcinoma of the breast.
The Neuropharmacology of Attention-Deficit Hyperactivity Disorder
Authors: Zametkin Alan J. , Borcherding Breck G.
Published: July 2003

Attention-deficit hyperactivity disorder, as described in the American Psychiatric Association's diagnostic manual DSM III-R (1), is a broadly defined syndrome of cognitive and behavioral problems that were originally found in children, but that have been increasingly identified in adults who had similar complaints in childhood (2). This paper briefly reviews the definition and treatment of this syndrome in children, evidence for specific neurochemical abnormalities, and effects of stimulants on neurochemistry. Finally, problems of diagnosis and treatment in adults are discussed.
Human Parvovirus Infections
Authors: Rothart Harley A.
Published: July 2003

The B19 strain ofparvovirus causes several distinct and important clinical diseases in humans. Aplastic crisis in patients with chronic hemolytic anemia, persistent bone marrow depression in immunocompromised individuals, and hydrops fetalis all result from direct infection of hematopoietic cells by the virus. Erythema infectiosum, arthritis, and purpuric vasculitis are postinfectious manifestations of B19 parvovirus infection.
The Gut as an Endocrine Organ
Authors: DelValle John , Yamada Tadataka
Published: July 2003

Gut hormones serve as chemical messengers for communication between different cells of the gastrointestinal tract. Several technologic advances have contributed to the rapid evolution of peptide hormone biochemistry and physiology. Peptide hormones are potentially useful as diagnostic and therapeutic modalities in the practice of gastroenterology.
Stunned and Hibernating Myocardium
Authors: Kloner Robert A. , Przyklenk Karin
Published: July 2003

Myocardium that is not functioning may be dead (infarct or scar), viable but stunned (postischemic ventricular dysfunction), viable but hibernating (chronic low flow state), or acutely ischemic. Stunned myocardium has clearly been documented (a) in experimental studies of brief coronary artery occlusion followed by reperfusion, and (b) in myocardial infarct models in which early reperfusion salvages viable tissue. Recent clinical studies have confirmed the existence of stunned myocardium in humans. Evidence supporting the concept of hibernating myocardium comes from clinical studies in which patients with chronic low flow ischemia exhibit improvement in left ventricular function (sometimes immediately) following revascularization.
Initiating Events of Acute Coronary Arterial Occlusion
Authors: Forrester James S. , Litvack Frank , Grundfest Warren
Published: July 2003

Acute myocardial infarction is caused by coronary thrombosis on an ulcerated atheroma. We now believe that the predominant cause of this intimal disruption is the rupture of the atheroma through the intimal surface, caused by enzymes released by activated macrophages. The subsequent clinical course following atheroma disruption is determined by the rate and size of thrombus formation. Partially occlusive thrombi produce unstable angina; completely occlusive thrombi produce myocardial infarction; clot embolization can produce sudden death. The localized thrombus lyses within days. The healing process, however, is frequently accompanied by rapid local progression of the size of the atheroma at the site ofintimal disruption. With healing of the intimal surface, the patient's clinical status stabilizes. Thus coronary disease is a cyclical phenomenon driven by cellular events within the atheroma and by the interaction of the atheroma with circulating blood elements.
Antiviral Therapy of HIV Infection
Authors: Richman Douglas D.
Published: July 2003

In only five years, antiretroviral therapy progressed from promising in vitro results with a newly recognized virus (HIV) to the standard practice of primary care applicable to hundreds of thousands of patients. With AZT (zidovudine) we have learned that we can prolong survival, reduce morbidity, and delay the progression of asymptomatic infection to disease. We have also learned that doses of AZT lower than those used in the original studies are as effective but less toxic. Additional compounds are under evaluation and more are needed to provide regimens, probably as combinations of drugs, that can be administered chronically with more efficacy, less toxicity, and diminished likelihood to select for drug-resistant virus.
Parenteral and Enteral Nutrition
Authors: Shizgal Harry M.
Published: July 2003

Stress and starvation, especially when complicated by sepsis, will give rise to a rapid erosion of the cellular mass, which significantly affects morbidity and mortality. The best clinical evaluation of the nutritional state is obtained from the medical history and the physical examination. In the patient who cannot eat a balanced diet, specialized nutritional support, in the form of either enteral or parenteral nutrition, is required to prevent malnutrition in the normally nourished, or to correct the nutritional state in the malnourished.
Lung Transplantation
Authors: Trulock E. P.
Published: July 2003

Lung transplantation has become a therapeutic option for appropriately selected patients with end-stage lung disease. Recipient selection guidelines are summarized, and the timing of transplantation is discussed. Functional results and survival statistics are reviewed.
The Ophthalmopathy of Graves' Disease
Authors: Carter Judy A. , Utiger Robert D.
Published: July 2003

Ophthalmopathy is an integral component of Graves’ disease. It usually appears at the same time as hyperthyroidism, and is characterized by proptosis (exophthalmos), periorbital and conjunctival edema, eye muscle dysfunction, and on occasion corneal ulceration or optic neuropathy. Graves’ ophthalmopathy, like Graves’ hyperthyroidism, is an autoimmune disease, but the mechanisms that initiate and maintain it are not known. Most patients can be treated conservatively, but a few require antiinflammatory or surgical therapy to relieve symptomsa nd preserve vision.
Physiologic Role of the Normal Pericardium
Authors: Watkins Matthew W. , LeWinter Martin M.
Published: July 2003

Because of the characteristics of the parietal pericardial tissue, the intact pericardial sac has a limited reserve volume, becoming relatively non-compliant when the heart volume is at the high end of the normal physiologic range. Pericardial restraint of the heart is best considered as a contact force. Measured with flattened balloons, the magnitude of pericardial contact pressure is probably several mmHg less than right atrial pressure. The diastolic pressure-volume relationship of the right ventricle, and to a lesser degree of the left ventricle, shifts downward following pericardiectomy. In dogs, the pericardium has been shown to limit maximal cardiac output. Some disease states associated with a rapid increase in total heart volume, including subacute mitral regurgitation and right ventricular infarction, demonstrate an increased pericardial influence on cardiac filling.
Bacterial Genetics
Authors: Cavalli-Sforza Luigi Luca
Published: July 2003

Microbial genetics is still in a phase of expansion and the splitting of the subject this year has somewhat relieved the reviewer's labours. The present paper attempts to cover the developments in the genetics of bacteria which have taken place in the years 1955 and 1956, i.e., subsequent to the publication of the previous review by Zelle (181). Work on phage will be considered only insofar as directly relevant. The author is also grateful to the editors for their encouragement in suggesting that attention be focussed on selected problems. The choice of subjects to which more space and time has been dedicated is inevitably dependent on the author's taste and background. Although a general picture has been attempted, omissions may have occurred, voluntarily or involuntarily. Moreover, the tyranny of space has made it impossible to consider cytology, radiation, and biochemical genetics, except for a few selected themes. Apologies are offered in advance to readers and writers for these omissions.

The following topics will be discussed: mechanisms of genetic transfer; genetic changes in individuals and populations; phenogenetics; some cytological contributions; taxonomy and the species problem.
THE LIPOPHOSPHOGLYCAN OF LEISHMANIA PARASITES
Authors: Turco Salvatore J. , Descoteaux Albert
Published: July 2003

Protozoan parasites of the genus Leishmania have the remarkable ability to avoid destruction in the hostile environments they encounter throughout their life cycle. The molecular details of how these pathogens persevere with impunity under harsh conditions are beginning to be understood. The fact that Leishmania parasites have adapted to not only survive, but to proliferate probably is due to the protection conferred by specialized molecules on the parasite's cell surface. One such macromolecule is a novel glycoconjugate called lipophosphoglycan. This heterogeneous, lipid-containing polysaccharide is the major surface molecule of the parasite and has been implicated in a surprisingly large number of functions that may contribute to the parasite's pathogenesis. This review emphasizes the structural aspects of lipophosphoglycan and its possible functions and biosynthesis.
CONTROL OF CELL DENSITY AND PATTERN BY INTERCELLULAR SIGNALING IN MYXOCOCCUS DEVELOPMENT
Authors: Kim Seung K. , Kaiser Dale , Kuspa Adam
Published: July 2003

Myxococcus xanthus cells feed, move, and develop cooperatively. Genetic, biochemical, and cell mosaic studies demonstrate that cells coordinate their multicellular behavior by transmission of intercellular signals. Starvation for amino acids at sufficiently high density on a solid surface initiates a series of events culminating in the formation of a multicellular structure called a fruiting body filled with dormant, environmentally resistant spores. This review discusses how myxobacteria use extracellular signals to sequentially check the density and arrangement of cells at different stages during development. For at least one early and one late developmental signal, cell density determines the efficiency of intercellular signaling. In turn, proper signaling insures that the appropriate cell density exists, thus controlling the progress of multicellular development in M. xanthus.
MOLECULAR DETERMINANTS OF THE VIRULENCE AND INFECTIVITY OF CALIFORNIA SEROGROUP BUNYAVIRUSES
Authors: Griot Christian , Gonzalez-Scarano Francisco , Nathanson Neal
Published: July 2003

California bunyaviruses cause encephalitis in mammalian hosts after peripheral infection. The virulence of these viruses is determined by their ability to replicate sequentially in striated muscle, cause viremia, and invade and replicate in the central nervous system. These viruses are also able to infect vector mosquitoes following ingestion of a blood meal containing virus. Bunyaviruses are negative stranded RNA viruses with a trisegmented genome, and the large, medium, and small RNA segments encode the polymerase, the glycoproteins, and the nucleoprotein, respectively. Reassortants between virulent and avirulent virus clones have been used to map virulence determinants in mice as well as determinants of infectivity in mosquitoes. Attenuation in mice and infectivity in mosquitoes of some virus clones maps to the medium RNA segment, implying that the virus glycoproteins, which are involved in virus entry, play a role in virulence. Attenuation in mice and mosquito infectivity of other clones maps to the large RNA segment, suggesting that cell-specific differences in the function of the viral polymerase can also determine virulence and host range.
THE ROAD TO YELLOWSTONE—AND BEYOND
Authors: Brock Thomas D.
Published: July 2003

This memoir describes the professional life and times of Thomas D. Brock, with an emphasis on those aspects of his career relating to research in microbial ecology, and how this work led to field research in Yellowstone. The first discovery of extremely thermophilic bacteria is described, followed by a discussion of some of the consequences of this discovery for biotechnology and microbiology. Also covered briefly in this memoir are Brock's activities in textbook writing, publishing, computers, and the history of science.
Sexually Dimorphic Behaviors
Authors: Kelley Darcy B.
Published: July 2003

Sex differences in behavior are the result of natural and sexual selection. The dimorphic classes of behavior described here, courtship, copulatory, and parental behaviors, reflect both kinds of evolutionary selective pressures. We can further distinguish two kinds of mechanisms that produce differences in male and female behaviors. In one, both sexes can perform a behavior but one does not because of sex differences in the external stimuli or the endocrine milieu. Maternal behavior in rodents falls into this category, as do certain other reproductive behaviors. In the other, the sensory, CNS, or motor components that produce behaviors are different in males and females. Many courtship and copulatory behaviors are in this category. I have considered some cellular mechanisms that generate sex differences in behavioral effector neurons, including sensitivity to hormones, cell number, and synaptic connectivity. A common feature of many such systems is a degree of developmental arrest: sexually dimorphic, hormone-sensitive neurons or muscles are immature at stages when other cells have completed differentiation. The cellular and molecular processes whereby hormones harness the developmental programs of behavioral effector cells remain largely unknown and are the focus of active investigation.
Blood, Birds, and the Old Road
Authors: Wilkinson Denys
Published: July 2003

This personal retrospective covers half a century of the development of our understanding of the atomic nucleus with particular reference to the writer’s involvement in it: nuclear instrumentation, nuclear photodisintegration, the early years of the shell model, nuclear symmetries, isospin, and β-decay.

“. . . a breaker of stones on an old road to a not yet clearly marked destination.”
Role of Vitamin K in Bone Metabolism
Authors: Vermeer C. , Jie K.-S. G. , Knapen M. H. J.
Published: July 2003

Vitamin K is a cofactor required for the formation of γ-carboxyglutamate (Gla) residues in proteins. Osteoblasts produce at least three different Gla-containing proteins: osteocalcin, matrix Gla-protein, and protein S. After cellular secretion of these proteins, the main part of each remains bound to the hydroxyapatite matrix in bone, but their function remains unclear. Part of the newly synthesized osteocalcin is also set free into the bloodstream, where it may be used as a diagnostic marker for bone formation. Several studies have demonstrated that a poor vitamin K status is associated with an increased risk of osteoporotic bone fractures. Whether vitamin K supplementation will reduce the rate of bone loss in postmenopausal women remains a matter of debate.
Roles of Ubiquitinylation in Proteolysis and Cellular Regulation
Authors: Wilkinson Keith D.
Published: July 2003

Most eukaryotic organisms respond to starvation, nutrient deprivation, and/or stress by increasing the rates of intracellular proteolysis. The amino acids released may be reutilized for synthesis of important proteins, or directly for the production of energy. This enhanced proteolysis is also required for repair of cellular damage due to environmental insults such as heat shock, free radicals, viral infection, or mutation. Finally, intracellular proteolysis is important in determining the steady-state levels of a wide variety of regulatory proteins, particularly those regulating the cell cycle. The ubiquitin-dependent proteolytic system participates in all of these functions. In spite of its cytoplasmic localization, this system is selective and acts only on a limited set of substrates. This review discusses the mechanisms of this selectivity and the potential roles of ubiquitin-dependent proteolysis.
The Evolution of National Nutrition Policy
Authors: Kessler David A.
Published: July 2003

Domestic regulatory efforts in the area of nutrition historically have focused on achieving and sustaining the highest possible level of food safety and availability. More recently, the linkages between certain dietary practices and the risk of chronic, degenerative diseases have also become a significant focus of public policy.

In order to promote good nutrition practices, the Food and Drug Administration (FDA) now requires a detailed and informative Nutrition Facts food label on virtually all food packages. Other public policies promoted by the FDA and others include increasing public knowledge of the relationship between diet and health; promoting unified food and nutrition policies among all government agencies; educating the American consumer about sound dietary practices; and encouraging the development of technologies that may result in more healthful, more abundant, and more affordable foods.
Mechanisms of Food Allergy
Authors: Sampson Hugh A. , Burks A. Wesley
Published: July 2003

Our understanding of food allergy has made tremendous strides recently. With now-relatively uniform definitions of the clinical presentations of food allergy, the scientific literature is more discernible. In this progress, we have come to understand that the prevalence of food allergy is up to 8% in children and 2% in adults. Additionally, these studies have shown the role of specific allergens and mediators in the immunopathogenesis of food allergy. Much of the information available still relates to immunoglobulin & mediated food reactions, although other immunologic mechanisms are being studied extensively. The diagnosis and treatment of food allergy is now much more standardized. Longterm studies have shown the natural history of many of these reactions.
Vitamin E in Humans: Demand and Delivery
Authors: Traber Maret G. , Sies Helmut
Published: July 2003

How much vitamin E is enough? An established use of supplemental vitamin E in humans is in the prevention and therapy of deficiency symptoms. The cause of vitamin E deficiency, characterized by peripheral neuropathy and ataxia, is usually malabsorption—a result of fat malabsorption or genetic abnormalities in lipoprotein metabolism. Genetic abnormalities in the hepatic α-tocopherol transfer protein also cause vitamin E deficiency—defects in this protein cause an impairment in plasma vitamin E transport. Impaired delivery of vitamin E to tissues, thereby, results in deficiency symptoms. Also discussed is the use of supplemental vitamin E in chronic diseases such as ischemic heart disease, atherosclerosis, diabetes, cataracts, Parkinson's disease, Alzheimer's disease, and impared immune function, as well as in subjects receiving total parenterol nutrition. In healthy individuals, a daily intake of about 15-30 mg of α-tocopherol is recommended to obtain “optimal plasma alpha-tocopherol concentrations” (30 μM or greater).
MECHANISM AND REGULATION OF SELENOPROTEIN SYNTHESIS
Authors: Driscoll Donna M. , Copeland Paul R.
Published: July 2003

▪ Abstract  Selenium is an essential trace element that is incorporated into proteins as selenocysteine (Sec), the twenty-first amino acid. Sec is encoded by a UGA codon in the selenoprotein mRNA. The decoding of UGA as Sec requires the reprogramming of translation because UGA is normally read as a stop codon. The translation of selenoprotein mRNAs requires cis-acting sequences in the mRNA and novel trans-acting factors dedicated to Sec incorporation. Selenoprotein synthesis in vivo is highly selenium-dependent, and there is a hierarchy of selenoprotein expression in mammals when selenium is limiting. This review describes emerging themes from studies on the mechanism, kinetics, and efficiency of Sec insertion in prokaryotes. Recent developments that provide mechanistic insight into how the eukaryotic ribosome distinguishes between UGA/Sec and UGA/stop codons are discussed. The efficiency and regulation of mammalian selenoprotein synthesis are considered in the context of current models for Sec insertion.
A Personal View of Pharmacology
Authors: Black James
Published: July 2003

This essay is an account of the author’s experience in trying to interpret the action of drugs as seen in in vitro bioassays. The central theme is how the development of simple mathematical models has assisted in the interpretation of drug actions. Starting from encounters with partial agonists, the essay describes the development of an operational model of agonist activity, the significance of receptor distribution, the analysis of indirect competitive antagonism and various two-receptor systems, followed by examples of pharmacological resultant activity. Analyses of tissue and species variations are described. The essay ends with an assessment of the future of bioassay in pharmacology
High-Pressure Structural Transformations in Semiconductor Nanocrystals
Authors: Tolbert Sarah H. , Alivisatos A. P.
Published: July 2003

Pressure-induced structural transformations in semiconductor nanocrystals are examined. High-pressure Raman spectroscopy, EXAFS, X­ray diffraction, and optical absorption are discussed as methods for studying these transformations in CdSe, CdS, and Si nanocrystals. In these nanocrystal systems, each technique shows an elevation in solid-solid structural transformation pressure as crystallite size decreases. By analogy with melting in nanocrystals, this elevation in transformation pressure is explained in terms of an increase in surface energy in the newly formed high-pressure phase crystallites. The increase in surface energy is in turn the result of transition path-induced changes in the shape of the nanocrystals. These changes convert spherical nanocrystals with low-index, low-energy surfaces into oblate or prolate crystallites with higher-index, higher-energy surfaces. The elevation in structural transformation pressure in nanocrystals is thus a kinetic rather than a thermodynamic phenomenon.
Prefatory Chapter: An Old Professor of Animal Husbandry Ruminates
Authors: Kleiber Max
Published: July 2003

When an old professor indulges in reminiscences some of his listeners may fear that he has reached the stage of rumination, and has therefore started to waste their time by rechewing old stuff. But a cow who indulges in chewing the cud assists her microbial co-workers by making material digestible which otherwise would be useless. I hope the readers of this preface will look at this more positive aspect of rumination and will bear in a friendly mood the frequent “I” and the seriousness with which I take myself and my cud.
Actions of Hormones in the Central Nervous System
Authors: Kostyo Jack L.
Published: July 2003

The endocrinology section of volume 49 is devoted to recent work and thought on the actions of hormones in the central nervous system. In all, seven chapters cover various aspects of the central actions of thyroid hormones, sex steroids, adrenal cortical steroids, insulin and certain gut peptides, and the renin-angiotensin system.
BRINGINGROBERTA. DAHL'STHEORY OFDEMOCRACY TOEUROPE
Authors: Fabbrini Sergio
Published: July 2003

▪ Abstract  The recent publication of all the essays and articles written by Robert A. Dahl between 1940 and 1997 is an occasion to note the capacity of Dahl's theory of democracy to address specific problems within specific democratic countries. This review draws the threads of Dahl's work together and then applies them to the European situation. Its aim is not only to give coherence to Dahl's lifelong research project but also to show that his theory may help identify the basic institutional and normative questions that the political development of European integration has to answer.
THEPOLITICALECONOMY OFHEALTH INTHEUNITEDSTATES
Authors: Wilkerson John D.
Published: July 2003

▪ Abstract  The United States pays a high price for its health system, and governments pay about half the costs. At the same time, the United States distinguishes itself by failing to provide health insurance for 15% of its population. In this article, I review research on the politics and economics of health to investigate three questions. Does this spending represent good value? Why does the United States spend so much on health? Finally, what technical and political challenges do policy makers face as they turn away from government solutions and toward market-based solutions to the challenge of balancing costs, access, and quality?
WHY THEUNITEDSTATESFOUGHT INVIETNAM
Authors: Berman Larry , Routh Stephen R.
Published: July 2003

▪ Abstract  Scholarship on the Vietnam war has advanced understanding of why the United States fought in Vietnam. An examination of this work leads us to consider several related topics, such as why North Vietnam won the war, why the United States and its ally South Vietnam lost the war, and whether there were missed opportunities whereby the U.S. military intervention could have been avoided. The disciplines of history and political science have illuminated many important aspects of the war ranging from such diverse subjects as presidential personality and leadership to congressional-executive relations. Political science has also contributed significant theoretical advances on the subject of why nations go to war and on the nature of international conflict, belief systems, and conflict resolution processes. By and large, however, we believe that most of the seminal discoveries on the subject of “why the United States fought in Vietnam” have been made by historians. We review several of these contributions with expectations that political science will build on this rich empirical foundation in hypothesis testing and theory development.
Terrorist Decision Making
Authors: McCormick Gordon H.
Published: July 2003

How do terrorists and terrorist groups make decisions? And what influence do terrorist decision-making styles have on the course of a terrorist campaign? Efforts to answer these questions have centered on three sets of theories. In order of generality, these are (a) strategic theories, in which the decision to employ terrorism and related forms of political violence is considered to be an instrumental choice; (b) organizational theories, in which the sources of violence are found in the internal dynamics of the terrorist group itself; and (c) psychological theories, in which the decision to employ terrorism is explained within the framework of individual psychology. Most observers agree that these lines of inquiry are not mutually exclusive, but each offers a distinctive approach to terrorist decision making. This essay examines each of these theoretical approaches in turn. It concludes with a brief discussion of the decision-making constraints that help shape terrorist life cycles.
POLITICAL SCIENCE ON THE PERIPHERY: Sweden
Authors: Ruin Olof
Published: July 2003

▪ Abstract  Swedish political science has a long pedigree. The Johan Skytte professorship of discourse and politics was established at Uppsala University in 1622, although political science teaching and research did not begin until the 1860s. Today, the discipline is represented at all 10 Swedish universities and at a number of other centers for higher education. Early Swedish political science gravitated toward constitutional law, history, and philosophy. In principle, the discipline today deals with all possible aspects of politics; as far as domestic politics research is concerned, special emphasis has been given to analysis of ideas, local politics, interest organizations, and political parties, as well as public administration and public policy. Contacts with the outside world have been close; different worldwide theories and methods have successively been incorporated. The relations between the discipline and the surrounding Swedish society have also been close and the reputation and visibility of the discipline fairly high.
ROBERTA. DAHL'SPHILOSOPHY OFDEMOCRACY, EXHIBITED INHISESSAYS
Authors: Bailey Michael , Braybrooke David
Published: July 2003

▪ Abstract  Dahl's collected essays give more weight to his achievements as a philosopher of democracy than to his empirical investigations. Nevertheless, they clearly reflect his habit of working close to empirical facts, in particular the problems created for democratic practices by the size of modern political societies, their pluralism, and their intricate involvement with capitalism. His trenchant account, under the head of “polyarchy,” of basic democracy, of the further criteria for full democracy, and of the conditions for achieving democracy at both these levels has established the current standard for discussing democratic theory. Moreover, he clears the way for continuing hope for democracy by demolishing (by arguments supported by observations) the ruling-elite model and advances the prospects of democracy by championing a variety of jurisdictional arrangements for citizens' participation.
Molecular Genetics of Sexuality in Chlamydomonas
Authors: Goodenough U. W. , Armbrust E. V. , Campbell A. M. , Ferris P. J.
Published: July 2003

Recent molecular and cellular data on the sexual cycle of Chlamydomonas reinhardtii, a unicellular green alga, is considered in the context of current theories on the origins and evolution of eukaryotic sex. The mating-type locus of C. reinhardtii controls gamete recognition and fusion, organelle inheritance, and sporulation, the three traits that characterize most sexual cycles in lower eukaryotes. The mating-type locus comprises approximately one megabase of DNA on linkage group VI, is highly rearranged in its central region, and contains identified genes that govern both recognition/fusion and chloroplast inheritance. Sporulation, a diploid program designed to negotiate changing environments, is analogous if not homologous to the somatic differentiation program of multicellular plants and animals, and its expression requires the fusion of compatible gametes.
Plant Genomes: A Current Molecular Description
Authors: Dean Caroline , Schmidt Renate
Published: July 2003

A major advance in plant genome analysis has been the development of molecular marker maps. These, in combination with repeated sequence analysis, have given considerable insight into the organization and evolution of many plant genomes. Physical mapping and sequencing of the genomes of the model plant species Arabidopsis thaliana and rice are progressing rapidly. The physical maps facilitate the isolation of genes by map-based cloning and will enable the organization of whole chromosomes to be analyzed. Comparative mapping studies between related plant species, using common sets of molecular markers, have revealed extensive collinearity over short chromosomal segments or whole chromosomes. Thus, in the future, collinearity as well as homology may be used to clone genes from many plant species, maximally exploiting the A. thaliana or rice physical maps.
Bayesian Statistical Methods in Public Health and Medicine
Authors: Etzioni Ruth D. , Kadane Joseph B.
Published: July 2003

This article reviews the Bayesian statistical approach to the design and analysis of research studies in the health sciences. The central idea of the Bayesian method is the use of study data to update the state of knowledge about a quantity of interest. In study design, the Bayesian approach explicitly incorporates expressions for the loss resulting from an incorrect decision at the end of the study. The Bayesian method also provides a flexible framework for the monitoring of sequential clinical trials. We present several examples of Bayesian methods in practice including a study of disease progression in AIDS, a comparison of two therapies in a clinical trial, and a case-control study investigating the link between dietary factors and breast cancer.
Ecologic Studies in Epidemiology: Concepts, Principles, and Methods
Authors: Morgenstern Hal
Published: July 2003

An ecologic study focuses on the comparison of groups, rather than individuals; thus, individual-level data are missing on the joint distribution, of variables within groups. Variables in an ecologic analysis may be aggregate measures, environmental measures, or global measures. The purpose of an ecologic analysis may be to make biologic inferences about effects on individual risks or to make ecologic inferences about effects on group rates. Ecologic study designs may be classified on two dimensions: (a) whether the primary group is measured (exploratory vs analytic study); and (b) whether subjects grouped by place (multiple-group study), by time (time-trend study), or place and time (mixed study). Despite several practical advantages of ecologic studies, there are many methodologic problems that severely limit causal inference, including ecologic and cross-level bias, problems of confounder control, within-group misclassification, lack of adequate data, temporal ambiguity, collinearity, and migration across groups.
The Importance of Human Exposure Information: A Need for Exposure-Related Data Bases to Protect and Promote Public Health
Authors: Wagener Diane K. , Selevan Sherry G. , Sexton Ken
Published: July 2003

As a subfield of public health, environmental health is concerned with evaluating and ameliorating the effects of people on the environment and the effects of the environment on people. Separating hazards from risks, and characterizing the magnitude, likelihood, and uncertainty of risks is at the heart of environmental health in the 1990s. To this end, a full range of data is needed, including data that characterize the distribution of hazards, the population potentially at risk, and the contact between people and pollution that creates the risk. Several government-sponsored data systems contain information on a range of exposure estimators. The challenge is to develop meaningful, properly validated models to identify public health needs and evaluate public health programs.
Understanding Research Synthesis (Meta-Analysis)
Authors: Mosteller Frederick , Colditz Graham A.
Published: July 2003

Synthesis of research findings has long been a part of reviewing and summarizing a field of study. Public health decisions are made on the available evidence. We summarize the approaches to research synthesis that draw on the best available evidence and the use of quantitative summaries through meta-analysis. We focus on observational studies. Heterogeneity offers the potential to observe a relation across study populations and circumstances. We emphasize the benefits of heterogeneity in overviews and the need to explore and describe the sources of heterogeneity. Random effects approaches to combining data are recommended, and the use of regression approaches is emphasized. Excluding studies with extreme results may bias a research synthesis and underestimate the true variance of the results, thus contributing to misleading inference. Thorough searching is the best guard against publication bias. We conclude with guidelines for combining epidemiological studies.
The Epidemiology and Control of Open Angle Glaucoma: A Population-Based Perspective
Authors: Tielsch James M.
Published: July 2003

Chronic open angle glaucoma is an etiologically heterogeneous group of diseases characterized by damage to the optic nerve, resulting in peripheral visual loss that can progress to involve the fovea and central vision. Open angle glaucoma can be divided into primary conditions and conditions which are secondary to another ocular or systemic disease. Causes of secondary glaucoma include uveitis, cataract, trauma, and disorders affecting the development structure of the angle. This review focuses on primary open angle glaucoma (POAG), since it accounts for the vast majority of the disease burden in the US population and its etiology remains unknown.
Healthy Cities: Toward Worldwide Health Promotion
Authors: Flynn Beverly Collora
Published: July 2003

Healthy Cities is a community problem-solving process for health promotion that began in Canada and Europe in the mid-1980s. Although Healthy Cities have expanded worldwide, there is limited scientific literature that documents the effects of these efforts. This review describes the dynamic status of Healthy Cities globally and summarizes what is known about these efforts. It is difficult to draw generalizations or clear differences between Healthy Cities and other efforts with similar objectives in the United States. There appears to be less variation among Healthy Cities in Europe, most likely because of the extensive technical support provided by the WHO European Regional Office to the Healthy Cities Project. Case descriptions present the diversity and types of activities of Healthy Cities. It is concluded that community participation and broad involvement from different sectors of the community are promising approaches to addressing urban problems.
Classification of Race and Ethnicity: Implications for Public Health
Authors: Mays Vickie M. , Ponce Ninez A. , Washington Donna L. , Cochran Susan D.
Published: July 2003

▪ Abstract  Emerging methods in the measurement of race and ethnicity have important implications for the field of public health. Traditionally, information on race and/or ethnicity has been integral to our understanding of the health issues affecting the U.S. population. We review some of the complexities created by new classification approaches made possible by the inclusion of multiple-race assessment in the U.S. Census and large health surveys. We discuss the importance of these classification decisions in understanding racial/ethnic health and health care access disparities. The trend toward increasing racial and ethnic diversity in the United States will put further pressure on the public health industry to develop consistent and useful approaches to racial/ethnic classifications.
Roy Markham: Pioneer in Plant Pathology
Authors: Matthews R. E. F.
Published: July 2003

I first met Roy Markham in September 1945, when I came to Cambridge after four years in the New Zealand army to begin research for the PhD in plant virology. As far as the University was concerned Dr. K. M. Smith was my supervisor, but I very rapidly came under Roy’s influence, and he was my de facto supervisor for three years. I came back to his group for four full years from 1952 to 1956 and later made several short visits to his laboratory both in Cambridge and, after the shift, in Norwich. Thus, I knew him well for a significant portion of his working life.

Roy made a number of seminal contributions to plant virology and thus to plant pathology. However, he was in no sense a plant pathologist himself. His formal training was in biochemistry, and he learned a great deal in the physical sciences on his own account. In the main thrust of his research, he was really one of the pioneers in that branch of science now known as molecular biology.
Thomas J. Burrill, Pioneer in Plant Pathology
Authors: Glawe Dean A.
Published: July 2003

Perhaps no other American plant pathologist is so deserving of the title “Pioneer of Plant Pathology” as Thomas J. Burrill. A product of the American frontier and a researcher and teacher of plant pathology before the science even had a name, Burrill was a pioneer in every sense of the word. His original research on the cause of fire blight resulted in the first major conceptual advance in plant pathology made by an American. He also played an important role as an administrator and teacher at the University of Illinois. Many of the problems Burrill faced during his long and distinguished career will sound familiar to academic scientists of our own time. In particular, he and his contemporaries contended with student unrest, flagging public interest in higher education, heavy teaching loads, and insufficient support for research activities. By any measure, Burrill was unusually successful in coping with these problems and he fashioned a career remarkable in its contributions to his university, the public, and the scientific community.
Pioneer Leaders in Plant Pathology: ES Luttrell
Authors: Hanlin Rirchard T.
Published: July 2003

ES Luttrell was a mycologist who spent 42 of his 44 professional years at the University of Georgia, first at the Georgia Experiment Station in Griffin and later at the main campus in Athens. He is best known for his innovative classification scheme for the perithecial ascomycetes, in which orders were based on patterns of ascomal ontogeny and mode of ascus dehiscence. This work established him as an authority on ascocarp development. His later studies on the classification of the Helminthosporium complex, in which he showed that small differences in conidium germination and structure could be correlated with distinct teleomorphs, brought him recognition from plant pathologists as well. These studies were notable for his attention to detail and the quality of his work. His contributions to mycology and plant pathology were numerous and varied and brought him various awards later in his career.