Showing papers by "University of California published in 1974"

Multicommodity Distribution System Design by Benders Decomposition

Abstract: A commonly occurring problem in distribution system design is the optimal location of intermediate distribution facilities between plants and customers. A multicommodity capacitated single-period version of this problem is formulated as a mixed integer linear program. A solution technique based on Benders Decomposition is developed, implemented, and successfully applied to a real problem for a major food firm with 17 commodity classes, 14 plants, 45 possible distribution center sites, and 121 customer zones. An essentially optimal solution was found and proven with a surprisingly small number of Benders cuts. Some discussion is given concerning why this problem class appears to be so amenable to solution by Benders’ method, and also concerning what we feel to be the proper professional use of the present computational technique.

The effect of austenitizing temperature on the microstructure and mechanical properties of as-quenched 4340 steel

Abstract: The effect of austenitizing temperature on both the plane strain fracture toughness,KIC, and the microstructure of AISI 4340 was studied. Austenitizing temperatures of 870 and 1200°C were employed. All specimens austenitized at 1200°C were furnace cooled from the higher austenitizing temperature and then oil quenched from 870°C. Transmission electron microscopy revealed an apparent large increase in the amount of retained austen-ite present in the specimens austenitized at the higher temperature. Austenitizing at 870°C resulted in virtually no retained austenite; only minor amounts were found sparsely scat-tered in those areas examined. A considerably altered microstructure was observed in specimens austenitized at 1200°C. Fairly continuous 100 to 200A thick films of retained austenite were observed between the martensite laths throughout most of the area exam-ined. Additionally, specimens austenitized at 870°C contained twinned martensite plates while those austenitized at 1200°C showed no twinning. Plane strain fracture toughness measurements exhibited an approximate 80 pct increase in toughness for specimens austen-itized at 1200°C compared to those austenitized at 870°C. The yield strength was unaffected by austenitizing temperature. The possible role of retained austenite and the elimination of twinned martensite in the enhancement of the fracture toughness of those specimens austen-itized at the higher temperature will be discussed.

Consequences of reperfusion after coronary occlusion. Effects on hemodynamic and regional myocardial metabolic function.

Abstract: Hemodynamic and regional metabolic measurements were obtained in seven closed chest dogs during a control period, 3 hours of coronary occlusion and 5 hours of reperfusion. Reperfusion resulted in intermittent ectopic arrhythmias in five dogs and severe shock in two. It usually caused increases in heart rate, coronary sinus flow and maximal isovolumetric rate of rise in left ventricular pressure (dP/dt), which were associated with a decrease in systemic pressure, left ventricular end-diastolic pressure, systemic vascular resistance and stroke work. A transitory increase in cardiac output occurred. Global myocardial oxygen consumption, which was reduced during occlusion, increased with reperfusion. Reperfusion induced abnormal lactate metabolism and myocardial potassium loss in the previously occluded area and often in the nonoccluded segment as well. Histopathologic changes of accelerated necrosis, reactive hyperemia and hemorrhage were often noted after reperfusion. These studies indicate that reperfusion after 3 hours of occlusion caused serious abnormalities in hemodynamic states, metabolic function and morphologic features of the heart.

Credible Means are exact Bayesian for Exponential Families

Abstract: The credibility formula used in casualty insurance experience rating is known to be exact for certain prior-likelihood distributions, and is the minimum least-squares unbiased estimator for all others. We show that credibility is, in fact, exact for all simple exponential families where the mean is the sufficient statistic, and is also exact in an extended sense for all regular distributions with their natural conjugate priors where there is a fixed-dimensional sufficient statistic.

Ultrasound Evaluation of Systolic Anterior Septal Motion in Patients With and Without Right Ventricular Volume Overload

Abstract: Little information is available concerning the normal systolic pattern of movement of the interventricular septum in man. Accordingly, we studied 242 patients without clinical or catheterization evidence of right ventricular volume overload (RVVO) employing the ultrasound continuous recording technique. In the plane of the mitral valve, systolic anterior septal motion (SASM) was present in 111 patients; in 38 patients the septum did not move during systole while in 74 patients, septal motion was variably anterior and posterior during the same recording. Normal posterior septal motion occurred in only 19 patients. However, at or below the level of the chordae tendineae, 226 of the 242 patients (93%) had normal posterior septal motion. The other 16 patients had severely impaired left ventricular function. In 56 patients with RVVO, 34 had abnormal septal motion at the level of the chordae tendineae (24 with SASM, 7 with variable motion and 3 with no movement). To evaluate septal motion further, 100 normal su...

Effect of Cigarette Smoking and Breathing Carbon Monoxide on Cardiovascular Hemodynamics in Anginal Patients

Abstract: Smoking high-nicotine cigarettes caused a significant increase in systolic and diastolic arterial pressure, heart rate, left ventricular end-diastolic pressure, and coronary sinus, arterial, and venous CO levels, no significant change in left ventricular dp/dt, aortic systolic ejection period, and cardiac index, and a significant decrease in stroke index and coronary sinus, arterial, and venous PO2 levels in eight anginal patients with documented coronary disease. One week later, these patients inhaled 150 ppm of carbon monoxide until their increase in coronary sinus CO was similar to that produced after smoking their third cigarette. Inhaling carbon monoxide caused a significant increase in left ventricular end-diastolic pressure and coronary sinus, arterial, and venous CO levels, no significant change in systolic and diastolic arterial pressure, heart rate, and systolic ejection period, and a significant decrease in left ventricular dp/dt, stroke index, cardiac index, and coronary sinus, arterial, and v...

Thyroid thermogenesis and active sodium transport.

Abstract: Publisher Summary This chapter presents an evidence in support of the hypothesis that thyroid hormone stimulates energy expended in active Na + transport in three of the primary thermogenic target tissues; liver, kidney, and skeletal muscle. In these tissues, this effect mediates a significant fraction and in some circumstances virtually all the thermogenic effect. This pathway does not appear to be the only mechanism involved in thermogenesis, however, in that from, one-half to two-thirds of the increase in Q O2 may be ouabain, or Na + , insensitive. It has been found that Ouabain has no effect on Q O2 of white fat from euthyroid controls or T 3 -treated rats. The chapter also explains that in this tissue, T 3 -stimulated respiration is secondary to changes in energy turnover in electron transport. The basic pathways involved in Na + transport-independent thermogenesis, however, remain undefined.

Impulsive (Flash) Phase of Solar Flares: Hard X-Ray, Microwave, EUV and Optical Observations

Abstract: Recent observations of impulsive hard X-ray, microwave, EUV and optical emissions during solar flares are briefly reviewed in order to deduce the characteristics of the impulsive (flash) phase phenomenon in small solar flares particularly from the point of view of the acceleration of electrons and their role in producing the various impulsive phase emissions. Observed and deduced characteristics of the various electromagnetic emission sources are summarized (Table II). The deduced characteristics of the electron acceleration process (Table III) indicate a process with high acceleration efficiency. The observations are found to be consistent with a model in which electrons are accelerated in a series of short pulses each lasting for ≲ 1 s and the accelerated electrons provide the energy necessary for all the observed electromagnetic emissions produced during the flash phase of small solar flares. Models of the impulsive phase emissions in which energetic electrons play a prominant role are examined and crucial tests to check the accuracy of these models are indicated (Table IV).

Some biological interactions affecting intertidal populations of the kelp Egregia laevigata

Abstract: Near Santa Barbara, California (USA), the large laminarian kelp Egregia laevigata (Setchell) occurred from the lower intertidal zone to subtidal depths. In the intertidal zone there was a large recruitment of E. laevigata in the spring. The kelp were largely excluded from a zone in the lowest intertidal zone where the surf grass Phyllospadix sp, grew, but were abundant on all other rock surfaces. Experiments demonstrated that, while neither grazers nor sessile organisms significantly reduced recruitment, E. laevigata of the previous year-class did so. There were also interactions among E. laevigata of the same year-class, expressed as a density-dependent mortality of very small algae, and as faster growth rates and greater number of branches of kelp at low densities. These processes tended to make both numbers and biomass of E. laevigata uniform. The mortality rates of large E. laevigata were so high that, in some locations, no kelp survived for more than 8 months. E. laevigata was, therefore, essentially an annual and opportunistic species in the intertidal zone.

Genetical Interference and Gene Conversion

Abstract: Gene conversion is a phenomenon associated with a high frequency of crossing-over of flanking markers (Mitchell, 1955; Case and Giles, 1964; Fogel and Hurst, 1967) Within a sample of 907 conversion events at four loci in the yeast Saccharomyces cerevisiae, 445 were associated with exchange of bracketing markers (Hurst et al, 1972) The finding that approximately 50% of the conversions were associated with crossing-over applied even when the bracketing alleles were in the same gene as the converted alleles These results imply a direct relationship between gene conversion and crossing-over A variety of different models have been proposed to explain recombination as a sequence of molecular events that may result in conversion alone, postmeiotic segregation, or either of these events associated with reciprocal recombination of outside markers (for review see Radding, 1973) A corollary of these models is that a reciprocal recombination event implies the occurrence of a conversion event somewhere between the recombined markers (Fogel and Mortimer, 1969; Paszewski, 1970) However, most and possibly all current models do not address themselves to the question of chiasma interference or the distribution of conversions and/or recombinations in adjacent genetic intervals

Human sexuality and evolution.

Abstract: My first experiment on reproductive behavior was published in 1937, and since that time most of my research has dealt with the neural, hormonal, and experiential control of sexual activity in various species of birds and mammals. In the course of nearly four decades I have authored, coauthored, or edited three books dealing with sexual behavior. Two years ago I decided to capitalize upon my experience as an experimentalist and author by teaching a new undergraduate course entitled “Human Sexuality.” The result was very nearly a total disaster.

Nomogram for modification of dosage regimens in patients with chronic renal function impairment

Abstract: A nomogram is presented for modifying dosage regimens of drugs administered to patients with chronic renal function impairment. The usefulness and limitations of the nomogram are discussed in terms of the objectives of dosage regimens. The nomogram is intended to serve as a guide for drug administration in patients with renal disease. It may be particularly helpful for drugs on which little or no definitive research has been undertaken.

The Theory of Homogeneous Isentropic Compression and its Application to Laser Fusion

Abstract: The hydrodynamic theory and properties of spherical homogeneous isentropic compression are discussed. Computer results are described showing that a close approximation to compressions of this type may be accomplished by light-induced pellet ablation if the light absorbed by the pellet is properly programmed with time, and is spatially uniform over the pellet surface. Pellet compressions in excess of ten thousand-fold are computed.

Effect of subacute administration of human growth hormone on various serum lipid and hormone levels of hypercholesterolemic and normocholesterolemic subjects

Abstract: Six hypercholesterolemic and five normocholesterolemic subjects were injected twice daily with human growth hormone for 7 days. During HGH administration, the average serum cholesterol of both types of subjects fell significantly, and their serum triglyceride levels increased. Peak insulin responses to glucose also increased. However, no change occurred in the serum phospholipid, FFA, cortisol, or thyroxine concentrations during HGH treatment.

The subjective, experiential element in perception.

Abstract: The problem of sentience and how we are to understand it is addressed. It is argued inter alia that sentience can find its place in psychological theory only in relation to perception and other modes of awareness. Basic issues examined, therefore, pertain to the subjective, experiential element in perception, to the qualitative contents of perceptual and imaginai awarenesses. These issues are basic to the theory of the percept (and image) and have to do with where and how to locate the experiential element in a materialist world view. Subjective knowledge of qualitative contents is no less structural than knowledge by description; any advantage that exists is in respect to a mode of knowing rather than in what can be known about them. The subject ‘participates’ in what he comes to know, but such participation does not make for knowledge unique to him. Nor does what he knows by this route count against qualitative contents belonging to brain processes, except perhaps for the problematic property of ‘grain’. The discussion proceeds via review and evaluation of a variety of relevant views and arguments.

Effect of Carbon Monoxide Exposure on Intermittent Claudication

Abstract: The effect of breathing 50 ppm of carbon monoxide for two hours versus compressed, purified air for two hours on intermittent claudication was evaluated in ten men in a double-blind study. The mean venous carboxyhemoglobin level insignificantly decreased from 1.12% to 0.90% after breathing compressed, purified air but significantly increased from 1.08% to 2.77% after breathing carbon monoxide (P < 0.001). The mean exercise time until the onset of intermittent claudication insignificantly increased from 169 sec to 173 sec after breathing compressed, purified air but significantly decreased from 174 sec to 144 sec after breathing carbon monoxide (P < 0.001). Breathing 50 ppm of carbon monoxide for 2 hr significantly aggravated intermittent claudication of the calf or thigh due to angiographically documented occlusive arterial disease.

The RecE Pathway of Bacterial Recombination

Abstract: There appear to be three pathways of recombination active or potentially active in strains of Escherichia coli (Clark, 1971, 1973). The operation of two of these three pathways has so far been associated with nuclease activities. The RecBC pathway makes use of exonuclease V (ExoV), the product of the recB and recC genes (see e.g. Goldmark and Linn, 1972). The RecE pathway does not use ExoV; it proceeds in cells that contain exonuclease VIII (ExoVIII). The RecF pathway also does not use ExoV. The RecF pathway appears to be inhibited by exonuclease I (Exol) in that it operates at high efficiency only when Exol is mutationally inactivated by sbcB mutations. Here we wish to consider the role that ExoVIII may play in the RecE pathway, particularly in comparison with the roles that can be postulated for ExoV in the RecBC pathway and for the exonuclease of lambda (Exoλ) in the Red recombination system of lambda.

Time-course of the effects of thyroid hormone on respiration and Na+ + K+-ATPase activity in rat liver.

Abstract: SummaryAs a further test of the hypothesis that increased energy expenditure in active Na+ transport mediates a major part of thyroid thermogenesis, time-course measurements were made of hepatic oxygen consumption (Qo2), Na+-dependent oxygen consumption [Qo2(t)] and Na+ + K+ adenosine-triphosphatase (NaK-ATPase) activity after a single or repeated injections of triiodothyronine (T3) into thyroidectomized and euthyroid rats. In both groups, after single injections, Qo2 and Qo2(t) increased to peak values at 48 hr and declined in parallel to close to the control level by the 6th day. In euthyroid rats, NaK-ATPase activity manifested the same time-course with a peak increase at 48 hr. In both groups, after repeated injections (every other day ×3), there were curvilinear increases in Qo2, Qo2(t) and NaK-ATPase activity to steady-state levels in 2-3 days. These findings are in accord with the inference that thyroidal stimulation of the Na+ pump mediates the increase in Qo2(t). In addition, we found that in hyp...

Pivot-Independent Relativization in Japanese

Abstract: It has generally been assumed that Japanese relativization consists of a simple process of deletion, in the relative clause, of a noun phrase coreferential with the noun phrase that the clause modifies. Thus, it has been believed that, as McCawley puts it, “a relative clause, whether restrictive or nonrestrictive, consists of a truncated sentence (specifically, a sentence which lacks the NP that is relativized over and any case markers that go with that NP”, and “the relative clause precedes the NP which it modifies”. 1 In a series of articles, I will present and discuss the claim that alongside this familiar type of relativization Japanese also possesses the type of relative clause which recently has increasingly drawn linguists’ attention and which is commonly referred to as ‘headless relative clause’.

Genetics of plasma cholesterol and triglycerides. A study of adult male twins

Abstract: Fasting plasma triglycerides and cholesterol, as well as cholesterol in very low density, low density and high density lipoproteins, were measured in 250 MZ and 264 DZ adult male twin pairs. A new method was used to choose an estimate of genetic variance. This includes an estimate of genetic variance for use when the total variances of MZ and DZ twins are unequal. DZ twins had greater total variance for cholesterol. When genetic variance was estimated by subtracting the within-MZ-sets mean square from the within-DZ-sets mean square, all of the lipids had significant estimates of genetic variance; however, when genetic variance was estimated by a method designed to correct bias due to unequal total variances of MZ and DZ twins, only triglycerides had significant genetic variance. The heritability of plasma triglycerides was calculated to be 0.68.

A Comparison of the Migratory Strategies of Two Milkweed Bugs, Oncopeltus Fasciatus and Lygaeus Kalmii

Abstract: Views on the nature of migration and dispersal in insects have changed markedly in the past 25 years. Williams (1957) in the 1940s and 1950s was largely responsible for calling attention to the large number of insect species which migrate. However, he stressed that insect migrations were mass occurrences, often triggered by unfavorable conditions, in which flight was unidirectional and under the control of the individual. Dispersal was considered to be mainly a passive and accidental process in which weak-flying insects were scattered by the wind. In the late 1950s, Rainey (1963) demonstrated that movements of African migratory locusts were correlated with prevailing wind patterns and suggested that the direction of migration in these strong fliers was independent of their orientation and thus also passively determined. This led to the questioning of whether or not there was a valid distinction which could be drawn, on the basis of directionality, between the so-called active migrants and passive dispersants. The problem was further complicated when considering the vertical and horizontal components of orientation and the fact that there was then, as there still is, so little data on the orientation of flying insects (Kennedy 1961). Waloff (1972) has recently presented evidence that locusts do in fact orient their direction of flight down wind, thus pointing to the difficulties in attempting to distinguish among dispersal strategies using orientation as a criterion.

The fourth dimension of geography

Abstract: A participant observer notes the manner of entry of Geography into American universities It was outlined and accepted as an earth science Its content is concerned with time as well as place, time that is nonrecurrent, ongoing rather than cyclic Digressions from this substantive orientation lead to nonproductive ends

Probability Distributions for Noise Plus Several Sine Waves--The Problem of Computation

Abstract: The problem of computing the distributions of the envelope and instantaneous value of the sum of several sine waves plus Gaussian noise is reviewed. It is pointed out that the associated integrals can be efficiently evaluated by the trapezoidal rule except when the noise is small. Approximations which hold when the noise is small are given.

Interviewing and Memory

Abstract: This paper examines information processing problems associated with decisions made during medical history interviewing, and links these decisions to the use of questionnaires with fixed-choice responses. In a medical history interview the physician’s summary statement does not reveal the reasoning employed in posing questions and deciding that appropriate answers have been obtained. The use of self-contained stimulus questions with fixed response choices in sample surveys poses a similar problem. In survey research we need to clarify the reasoning attributed to the respondent, and the researcher’s decision-making, in arriving at acceptable questions, answers and relationships among stipulated variables. These two strategies for obtaining information do not deal adequately with the emergent conditions of interview settings. The emergent conditions include spontaneous variations in the language used, several levels of semantic information processing, shifting definitions of the problem and a problematic use of stimulus questions. These conditions, seen as natural to all interviewing, will be addressed in this paper.

Some comments on typologies in archaeology and an outline of a methodology

Abstract: Classification is discussed as a procedure for maximizing information about a cultural system from archaeological data. This concept is made rigorous by defining typologies in terms of assumptions about patterning among variables that result from different artifacts being manufactured for use in different activities. Interval-scaled and nominal-scaled variables are considered independently, as the problem to be solved is different in the 2 cases. For continuous variables, the question is what divisions can be made, and for nominal variables, it is what divisions should be made. Two definitions for typologies are given, 1 for continuous variables and 1 for nominal variables. Cluster analysis and analysis of interaction and residuals in contingency tables are outlined as procedures for discovering types with continuous and nominal variables, respectively. Examples of each technique using archaeological data are given.

An extensive behavioural and genetic analysis of the pawn mutants in Paramecium aurelia.

Abstract: Pawns are behavioural mutants which show impairment in membrane excitability and are, therefore, devoid of normal avoiding reactions. We obtained 103 lines of Pawns through mutagenesis and screening. Among those that yielded to breeding studies, 59 lines belonged to the pwA complementation group and 38 lines belonged to the pwB group. No other genic loci were found in this extensive analysis. Mutants of the pwA locus showed various degrees of phenotypic leakiness. Based on the pheno- and genotypic differences, we estimated that at least 45 independent mutational events were represented in these 103 Pawn lines.