Showing papers by "University of California published in 1980"

Why Collaborate? Issue-Linkage and International Regimes

Abstract: Why do nations create institutionalized modes of multilateral collaboration? How can common interests develop in the face of inequalities in power and asymmetries in interdependence? The author explores the role of knowledge in the definition of political objectives and interests. The systematic interplay of changing knowledge and changing objectives results in the redefinition of “issues” and the practice of “issue linkage.” The dynamics of issue-linkage, in turn, tell us something about international regimes for the management of progressively more complex issue areas. An ideal-typical “regime” is described, theoretically applicable to all types of issues. Since the cognitive attributes of the actors who set up such a regime cannot be expected to remain stable, this concept of a “regime” can illuminate cliscussion and analysis, but cannot be expected to provide a clear model for desirable policy. However, it can illustrate the options open to policy makers wishing to choose a mode of collaboration. Regimes dealing with money, the oceans, and technology transfer are used for illustrative purposes.

Précis of The evolution of human sexuality

Abstract: Patterns in the data on human sexuality support the hypothesis that the bases of sexual emotions are products of natural selection. Most generally, the universal existence of laws, rules, and gossip about sex, the pervasive interest in other people's sex lives, the widespread seeking of privacy for sexual intercourse, and the secrecy that normally permeates sexual conduct imply a history of reproductive competition. More specifically, the typical differences between men and women in sexual feelings can be explained most parsimoniously as resulting from the extraordinarily different reproductive opportunities and constraints males and females normally encountered during the course of evolutionary history. Men are more likely than women to desire multiple mates; to desire a variety of sexual partners; to experience sexual jealousy of a spouse irrespective of specific circumstances; to be sexually aroused by the sight of a member of the other sex; to experience an autonomous desire for sexual intercourse; and to evaluate sexual desirability primarily on the bases of physical appearance and youth.The evolutionary causes of human sexuality have been obscured by attempts to find harmony in natural creative processes and human social life and to view sex differences as complementary. The human female's capacity for orgasm and the loss of estrus, for example, have been persistently interpreted as marriage-maintaining adaptations. Available evidence is more consistent with the view that few sex differences in sexuality are complementary, that many aspects of sexuality undermine marriage, and that sexuality is less a unifying than a divisive force in human affairs.

Task Allocation in Distributed Data Processing

Abstract: Load balancing increases throughput but creates interprocessor overhead. This research suggests that a programming approach is the task allocation strategy most likely to balance these conflicting factors.

Structure of the low latitude boundary layer

Abstract: Observations at high temporal resolution of the frontside magnetopause and plasma boundary layer, made with the LASL/MPE fast plasma analyzer onboard the ISEE 1 and 2 spacecraft, revealed a complex quasiperiodic structure of some of the observed boundary layers. A cool tailward streaming boundary layer plasma was seen intermittently, with intervening periods of hot tenuous plasma which has properties similar to the magnetospheric population. While individual encounters with the boundary layer plasma last only a few minutes, the total observation time may extend over one hour or more.

Are central pattern generators understandable

Abstract: Most rhythmic behaviors are produced by a specialized ensemble of neurons found in the central nervous system. These central pattern generators (CPGs) have become a cornerstone of neuronal circuit analysis. Studying simple invertebrate nervous systems may reveal the interactions of the neurons involved in the production of rhythmic motor output. There has recently been progress in this area, but due to certain intrinsic features of CPGs it is unlikely that present techniques will ever yield a complete understanding of any but the simplest of them. The chief impediment seems to be our inability to identify and characterize the total interneuronal pool making up a CPG. In addition, our general analytic strategy relies on a descriptive, reductionist approach, with no analytical constructs beyond phenomenological modeling. Detailed descriptive data are usually not of sufficient depth for specific model testing, giving rise instead to ad hoc explanations of mechanisms which usually turn out to be incorrect. Because they make too many assumptions, modeling studies have not added much to our understanding of CPCs; this is due not so much to inadequate simulations as to the poor quality and incomplete nature of the data provided by experimentalists.A basic strategy that would provide sufficient information for neural modeling would include: (1) identifying and characterizing each element in the CPG network; (2) specifying the synaptic connectivity between the elements; and (3) analyzing nonlinear synaptic properties and interactions by means of the connectivity matrix. Limitations based on our present technical capabilities are also discussed.

Characteristics that predict risk of breast cancer before and after the menopause

Abstract: In a case-control study of 1868 breast cancer patients and 3391 control patients we searched for characteristics that predicted risk of breast cancer diagnosed before and after menopause. Common to increased risk of this disease in both periods of womanhood were: early menarche and late menopause; delayed marriage and first childbirth; more nulliparity or reduced gravidity and parity; reduced frequency of abortions; shorter overall child-bearing interval; more advanced education, higher socioeconomic status, and more contraceptive usage; and familial tendencies toward the disease. Breast cancer patients diagnosed before menopause were leaner than controls at age 20 and at time of diagnosis, but breast cancer risk in the postmenopausal period was related to increased weight-for-height at diagnosis and greater weight-for-height at diagnosis and greater weight gain since age 20. Postmenopausal breast cancer patients had a longer interval between first and second childbirths. Frequency and duration of the gravid state, inversely related to breast cancer risk, were largely dependent on contraceptive practices rather than unexplained infertility per se. Whether the breast cancer reaches diagnosis before or after menopause, the bulk of evidence examined here supports the view that it has a common cause and is subject to modifying influences over the long period of cancer latency.

Mechanisms Regulating Pattern Formation in the Amphibian Egg and Early Embryo

Abstract: Interest in pattern regulation arose with the first experiments of embryology almost a century ago. The hypotheses of His and Weismann (reviewed by Wilson, 1896) predicted that the fertilized egg behaves as a mosaic of autonomously differentiating parts, due to either the invisible promorphology of its cytoplasm (His) or the preexisting architecture of its chromosomes (Weismann). Roux’s first experiments in 1888 seemed to support these hypotheses: he pricked a frog egg (Rana esculenta) at the two-cell stage with a hot needle so as to inactivate one cell, hence half the egg, and found the other cell continuing to divide and in many cases developing into a half-embryo, usually a right or left half. Thus, the active cell failed to adjust its development to compensate for its defective neighbor, at least under these experimental conditions. The frog egg appeared to meet the definition of a mosaic egg, that is, one showing no pattern regulation.

Bone morphogenetic protein process

Abstract: The process of separating bone morphogenetic protein (BMP) from bone tissue comprising the steps of demineralizing bone tissue; treating the demineralized bone tissue under aqueous conditions with a water soluble neutral salt and a solubilizing agent for the BMP, the agent being selected from the group consisting of urea and guanidine, and thereby transforming the bone collagen to gelatin and extracting BMP into the solution of solubilizing agent; and separating the solubilizing agent and neutral salt from the solution, thereby precipitating BMP in the aqueous medium.

Productivity of Zooxanthellae

Abstract: Zooxanthellae are photosynthetic unicellular marine algae endosymbiotic with marine invertebrates. The term is a vernacular derivation of the original genus Zooxantheila, coined by Brandt (1) to describe the dinoflagellate symbionts of the radiolarian Collozoum inerme Haeckel, but now used to describe almost any yellow-brown unicellular algal symbiont. Analysis of zooxanthellae taxonomy and the evidence for genetic diversity of zooxanthellae is reviewed elsewhere (2, 3, 4, 5, 6, 7, 8, 9).

Estimating Phytoplankton Growth Rates in the Central Oligotrophic Oceans

Abstract: Measurements of primary production in the ocean by the 14C method are not as useful as simultaneous assessments of production and the phytoplankton standing stock. To a first approximation the two measurements together allow estimation of phytoplankton growth rate (μ) since $$ \frac{1} {{\text{P}}}\frac{{\Delta {\text{P}}}} {{\Delta {\text{t}}}} = \mu $$ (1) where P is the standing stock and ΔP/Δt the production rate. It is the estimation of μ which allows comparison of the field data to the large literature on algal physiology based upon careful laboratory measurements. This literature provides guidelines for judging the reliability of the field data as it sets limits for the likely values of μ as a function of environmental variables such as temperature, irradiance, daylength and concentrations of dissolved substances. Without such comparison there is no basis for judging the value of the field data except by comparison with other such data from similar habitats. Both data sets might be in error, however, because of common problems in conceptor methodology. Bannister (1, 2) has made comparisons of field data on photosynthesis rate and chlorophyll with laboratory data, but the latter data base including these measurements is very small. Ultimately the carbon/chlorophyll ratio of the phytoplankton is needed to make comparisons between photosynthesis/chlorophyll and growth rate (3).

Hippocampal substrate of classical conditioning

Abstract: Results of a series of studies from our laboratory are reviewed which demonstrate that in simple associative conditioning paradigms there is a very early and marked increase in hippocampal neuron activity that precedes and predicts the development of behavioral learning, both over the trials of training and in terms of the actual amplitude-time course of the appropriate conditioned behavioral response being learned. Current approaches to the study of the possible behavioral functions of the hippocampus are examined, and current theories of hippocampal function are evaluated in the context of our experimental results.

Pharmacokinetics and bioavailability of prednisone and prednisolone in healthy volunteers and patients: A review

Abstract: Limited information is available on the pharmacokinetics and bioavailability of prednisone and prednisolone in patients with different disease states. This is partly due to difficulty in measuring these drugs in biological fluids at the usual dosages prescribed to patients. This article attempts to comprehensively review these studies categorized under the following four sections: (1) bioavailability—healthy volunteers, patients with respiratory disease, patients with liver disease, patients with kidney disease, pediatric patients with various diseases, effect of antacids, effect of food, effect of other drugs (aminophylline, cholestyramine); (2) pharmacokinetics—healthy volunteers, patients with respiratory disease, patients with liver disease, patients with kidney disease, pediatric patients with various diseases, effect of other drugs, enzyme induction of steroids and the effect on the kinetics of steroids and other drugs; (3) protein binding; and (4) analytical methods. The literature is reviewed through August 1979.

Heuristic modeling of drug delivery to malignant brain tumors

Abstract: It is apparent that chemotherapy against malignant brain tumors is generally ineffective. While some agents are more effective than others, none appreciably alters the clinical course of and the poor prognosis for patients with brain tumors. Even though new and more effective agents are being or will be developed, chemotherapy depends as much on the delivery of drug as it does on the drug used. Therefore, we have defined factors that we believe are of primary importance in drug delivery to brain tumors, and, using computer simulation, we have modeled the effects of these factors. In this article we discuss (a) the extent of the "breakdown" in the blood-brain barrier (BBB) that accompanies the development of malignant tumors in the brain, (b) factors that influence drug transport from tumor capillaries to tumor cells at varying distances from the capillaries, (c) the problems inherent in drug delivery from a well-vascularized tumor outward to normal brain tissue that might harbor malignant cells but that does not have leaky vessels (i.e., normal BBB), and (d) the difficulties in drug delivery from a well-perfused, highly permeable outer tumor shell to a central, poorly perfused tumor core.

Hepatic Disease and Drug Pharmacokinetics

Abstract: Recent clinical investigations and reports of theoretical models have provided considerable insight into mechanisms of hepatic drug elimination and into derangements that may occur in drug absorption and disposition in patients with hepatic disease. Carefully conducted and well controlled clinical studies have demonstrated that hepatic disease may alter substantially one or more pharmacokinetic parameters of drug absorption and disposition. Phvsiological models of hepatic drug elimination have emphasised the importance of physiological variables such as hepatic blood flow, protein binding and intrinsic clearance of the liver on hepatic drug elimination. Both clinical investigations and theoretical considerations have indicated that the influence of hepatic disease on the pharmacokinetics of a drug may be complex and may result in either unchanged, retarded or even accelerated drug elimination. Changes in response to drugs in patients with hepatic impairment add to this complexity. Although general guidelines may be formulated now to assist clinicians in constructing dosage regimens of several important drug classes (notably the benzodiazepines and burbiturates) in hepatic disease. it is not now possible to predict in an individual the influence of a specific hepatic disease on the disposition of a drug, with the exception that the oral availability of drugs with high hepatic extraction ratios is increased in patients with cirrhosis and portacaval shunting of blood. Attempts to correlate concentrations of endogenous substances (such as bilirubin). or the pharmacokinetics of model drugs (such as antipyrine), with the pharmacokinetics of drugs that are useful in patients with hepatic impairment have not resulted in clinically useful tests of hepatic drug elimination. Following the administration of a drug to a patient with hepatic impairment, careful monitoring of the patient and also monitoring of plasma or blood drug concentrations remain important considerations.

Cross-Linking of Proteins to Nucleic Acids by Ultraviolet Light

Abstract: Early in the 1960s Smith (1962) and Alexander and Moroson (1962) independently published experimental results indicating that absorption of ultraviolet light could induce cross-linking of protein to DNA in living cells. Since these initial observations there has been increasing experimental interest in photoinduced cross-linking of proteins to nucleic acids. Photobiologists are intrigued by the possibility that nucleic acid-protein cross-linking is an important mode of ultraviolet light induced damage in biological systems. Molecular biologists and biochemists interested in structural relations in nucleic-acid-protein systems (e.g., chromatin, ribosomes) are examining the feasibility of using UV-cross-linking as a means of determining contact points between nucleic acid and protein in these complexes. Photochemists are exploring the structures and mechanisms of formation of adducts of nucleic acid bases and related compounds with amino acids and amino acid analogs; these studies may have direct relevance to the goal of understanding the chemical basis of UV-induced cross-linking in nucleic acid-protein complexes.

Insecticide resistance and prospects for its Management

Abstract: After a decade of relative neglect, resistance to insecticides1 is again beginning to receive the attention it deserves as a challenging problem that requires new solutions.

What the Nose Learns from the Mouth

Abstract: The mouth is a border zone dividing the feeding domain into two separate regions, each with its own empirical laws. The first region is the external arena, in which terrestrial animals cope with signals precisely located in space and time to obtain food or drink. The second is the internal homeostatic pool, which places demands for food or drink upon the animal. Pavlovian laws of conditioning were formulated in the external environment, where the flavor of food acts like an unconditioned stimulus (UCS) which, if applied promptly, can be used to modify a vast array of coping behaviors in man, rat or pigeon. These same laws do not apply to the internal environment, where the flavor of food acts more like a conditioned stimulus (CS) and a specialized visceral feedback acts as the UCS to modify the specific flavor incentive for which man, rat or pigeon strives.

An algorithm and computer program for deconvolution in linear pharmacokinetics

Abstract: The procedure of deconvolution to evaluate the rate and the extent of input from absorption data and data from intravenous administration is the most fundamental and least assumptive method of accurately evaluating drug absorption in linear pharmacokinetics. It is shown for linear systems that if the absorption response and the response from an intravenous infusion or bolus administration are both well approximated by a polyexponential function, then the rate of absorption can be expressed as a sum of exponentials. An algorithm and computer program are presented whereby the absorption function is uniquely defined from the model-independent parameters of the polyexponential expressions fitted to the absorption data and data from intravenous administration. Fitting a sum of exponentials to data has become a routine procedure in pharmacokinetics. The method presented therefore makes the previously complex task of deconvolution a simple procedure. The deconvolution approach is discussed in relation to conventional methods of evaluating drug absorption and appears to have some distinct advantages over these methods. The method is tested using simulated data and demonstrated using pentobarbital and cimetidine data from human subjects.

The Shang State as Seen in the Oracle-Bone Inscriptions

Abstract: This paper was first prepared as a documentary appendix to “The Late Shang State: When, Where, and What?” (to be published in the conference volume, The Origins of Chinese Civilization), which, by analyzing a series of thirty-nine “state criteria” under the general headings of Sovereignty, Territoriality, Religion and Kinship, Alliance and Warfare, and Exchange, attempted to classify the state in developmental terms. The present paper presents the documentary evidence in more detail by translating and discussing characteristic Inscriptions (generally from period I, the reign of Wu Ting) within each of the thirty-nine criteria. In so far as possible, the discussion focuses on the case of the Chou as a Shang state member. The evidence is particularly valuable because of the insights it gives Into the daily activities of the Shang theocrat.

Mechanism and Regulation of Ethylene Biosynthesis

Abstract: Ethylene is a plant hormone which initiates fruit ripening and regulates many aspects of plant growth and development (1). The role of methionine as a biological precursor of ethylene was first reported by Lieberman et al. (2), and now it is well established that methionine is the common precursor of ethylene throughout the diversity of higher plant tissues (3). In this conversion, C-1 of methionine is converted to CO2, C-2 to formic acid and C-3,4 to ethylene. The sulfur atom, however, is retained in the tissue (3, 4). Since the conversion of methionine to ethylene is greatly inhibited by uncouplers of oxidative phosphorylation, Burg (4), and Murr and Yang (5) have proposed that SAM , formed from methionine and ATP, is an intermediate between methionine and ethylene. Adams and Yang (6) have presented evidence showing that MTA and its hydrolysis product, MTR, are derived from the CH3S group of methionine during its conversion to ethylene and have substantiated the role of SAM as an intermediate in the biosynthesis of ethylene from methionine. More recently, Adams and Yang (7) have identified ACC as an intermediate between SAM and ethylene. In this paper we summarize our recent results pertinent to the role of ACC in ethylene biosynthesis and its regulation.

The Life of Music in North India: The Organization of an Artistic Tradition

Abstract: Daniel M. Neuman offers an account of North Indian Hindustani music culture and the changing social context of which it is part, as expressed in the thoughts and actions of its professional musicians. Drawing primarily from fieldwork performed in Delhi in 1969-71?from interviewing musicians, learning and performing on the Indian fiddle, and speaking with music connoisseurs?Neuman examines the cultural and social matrix in which Hindustani music is nurtured, listened and attended to, cultivated, and consumed in contemporary India. Through his interpretation of the impact that modern media, educational institutions, and public performances exert on the music and musicians, Neuman highlights the drama of a great musical tradition engaging a changing world, and presents the adaptive strategies its practitioners employ to practice their art. His work has gained the distinction of introducing a new approach to research on Indian music, and appears in this edition with a new preface by the author.

Table-Driven Code Generation

Abstract: This research shows that the systematic organization provided by table-driven methods provides many more benefits than the ad hoc code generation techniques of the past.

Nonlinear Social Welfare Functions: Do Welfare Economists Have a Special Exemption from Bayesian Rationality?

Abstract: It is argued that Bayesian decision theory is a solution of an important philosophical problem, viz. the problem of how to define rational behavior under risk and uncertainty. The author has shown in earlier papers that if we take the Bayesian rationality postulates seriously, and take an individualistic point of view about social welfare, then our social welfare function must be a linear function of individual utilities: indeed, it must be their arithmetic mean. The present paper criticizes Diamond’s and Sen’s contention that one of the Bayesian postulates (viz. the sure-thing principle) does not apply to social decisions, even though it may apply to individual decisions. It also criticizes Sen’s proposal of making social welfare a nonlinear function of individual utilities. The social welfare function proposed by the author depends on interpersonal utility comparisons. The use of such comparisons is defended. It is also argued that anybody who feels that the utilitarian (i.e., linear) form of the social welfare function is not egalitarian enough, should reject the author’s individualism axiom, instead of trying to reject the Bayesian rationality axioms. However, this would be equivalent to giving egalitarian considerations a priority in many cases over humanitarian considerations. Finally, the paper discusses the reasons why even full agreement on the mathematical form of the social welfare function would not give rise to a Utopian state of moral consensus: moral controversies arising from disagreements about what predictions to make about future empirical facts would still remain.

Multiple-Time-Scale Concepts in Turbulent Transport Modeling

Abstract: Progress in developing a turbulence closure employing two or more independently calculated time scales with which to characterize the rates of progress of different turbulent interactions is reported. The energy containing part of the spectrum is divided into two regions which respond at different rates and in different ways to changes in the environment. The scheme may be regarded as providing an intermediate level of approximation between the relatively simple, but fallible, single-point closures and the vastly more elaborate two-point closures which have so far been applied only to simulating homogeneous flows. The proposed approach requires only slightly more computational effort than single-scale schemes. Computational results are reported for several thin shear flows which show striking improvement in the level of agreement with experiment over that obtained with models employing only one time scale.

Antianginal and myocardial metabolic properties of verapamil in coronary artery disease

Abstract: To determine the metabolic cost of administering an experimental calcium antagonist, verapamil, to patients with coronary artery disease, 12 such patients were studied at rest and during stress with atrial pacing before and after intravenous treatment with verapamil (bolus dose of 0.1 mg/kg body weight, followed by infusion at 0.005 mg/kg per min). The mean (±standard deviation) aortic pressure at rest (98 ± 22 mg Hg), coronary sinus blood flow (88 ± 17 ml/min) and myocardial oxygen consumption (10.7 ± 2.4 ml O2/min) decreased to 88 ± 20 mm Hg (p < 0.0004), 77 ± 14 ml/min (p < 0.03) and 8.8 ± 2.5 ml O2/min (p < 0.01), respectively, after administration of verapamil. With atrial pacing, these values were 105 ± 25 mm Hg, 151 ± 50 ml/min and 18.5 ± 6.4 ml O2/min, respectively, before infusion of verapamil, and then decreased to 87 ± 14 mm Hg (p < 0.006), 107 ± 31 ml/min (p < 0.0002) and 13.3 ± 4.4 ml O2/min (p < 0.001) during infusion. Angina occurred in all patients with atrial pacing before verapamil (threshold to pain: 93 ± 67 seconds). After verapamil, the threshold to pain in six patients increased to 191 ± 183 seconds; and no pain was experienced by the remaining six (p < 0.0005). Before administration of verapamil lactate extraction decreased from 24 ± 9 to 10 ± 11 percent (p < 0.0002) during atrial pacing, and 9 (75 percent) of the 12 patients exhibited electrocardiographic S-T segment depressions. After administration of verapamil lactate extraction normalized to 22 ± 9 percent during atrial pacing, and the electrocardiogram reverted to baseline in all but one patient. These findings indicate that verapamil decreases left ventricular myocardial metabolic demands, and concomitantly greatly increases the threshold to angina.

The Current Status of Analgesic Brain Stimulation

Abstract: This paper reviews the author’s nine years of experience in analgesic brain stimulation. During this time, of 22 patients with pain of peripheral origin who were treated with periaqueductal gray (PAG), stimulation 16 achieved successful control of pain. Of 40 patients who presented with deafferentation pain, 16 were able to control their dysesthesia by brain stimulation of the subcortical somatosensory region alone; follow-up was over a long period. The mechanism of deafferentation pain is poorly understood and the effectiveness of subcortical somatosensory electrical stimulation to relieve such pain is based on empirical observation. The analgesia produced by PAG stimulation appears to be mediated by the release of beta-endorphin from the anterior hypothalamus. The released beta-endorphin binds to the Opiate reeeptors in the PAG and activates the descending pain-inhibitory pathway. However, the repetitive stimulation of this serotonergic system produces tolerance to its analgesic effect, due to a decreased rate of Serotonin turnover. Loading of the serotonin precursor by dietary supplementation of the essential amino acid L-tryptophan reverses this tolerance.