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Comparative coronary sinus flow rates and oxygen AV difference were studied in dogs undergoing left heart bypass with left atrial or left ventricular drainage at similar maximum obtainable flow rates. Left atrial bypass decreased the coronary sinus flow rates and oxygen consumption when compared with control values. These values were further decreased when left ventricular bypass was used. The oxygen consumption data were highly significant and give further evidence of increased effectiveness of complete bypass of the left ventricle in myocardial support systems.

A variant of glucose-6-phosphate-dehydrogenase deficiency associated with chronic hereditary hemolytic anemia was discovered in a 9-yr-old white male. The erythrocytes contained 5% of normal enzyme activity, the Km NADP was two to three times normal, the pH optimum was decreased, and the heat stability was markedly decreased. The Km G6PD, electrophoretic mobility (B), and utilization of substrate analogues 2-deoxy-G6P and deamino-NADP were normal. The activity of G6PD in the leukocytes and platelets was 15% and 28% of normal values, respectively, but bactericidal activity and platelet function were unaffected by the deficiency of G6PD.

Vertical wind profiles above dryland wheat fields were measured simultaneously in the open and at horizontal distances of 2H, 4H, and 8H (H = shelterbelt height) in the lee of a highly permeable tree shelterbelt. Two-dimensional wind reduction patterns in the lee of the shelterbelt are presented. The effects of measurement height and atmospheric stability on the horizontal wind profiles (wind reduction curves) are presented. The wind reduction curves were most consistent during neutral atmospheric conditions. Drag coefficients for the shelterbelt were calculated utilizing the wind reduction curve data in a model by Seginer and Sagi (1972). Shelterbelt drag, characterized by the integrated wind reduction curve or a drag coefficient, is suggested as a practical basis for comparison of the effectiveness of different field shelterbelts. Utilization of the drag coefficients showed the 4-year old highly permeable windbreak was already 1 3 as effective as a fully grown shelterbelt.

Vasopressin causes a decrease in electrical resistance of phosphatidylserine bilayers. The magnitude of the decrease is a function of vasopressin and salt concentrations. The conducting channel is produced probably by aggregation of 4–5 molecules of the hormone.

This paper is a critical analysis of David Rayfield's attempt to distinguish true from correct descriptions of human actions (Inquiry, Vol. 13 [1970], Nos. 1–2). It is argued that the analysis fails to do the job required of it for two reasons. First, the analysis of true descriptions is circular insofar as it turns on the notion of an ‘unbound action’. Secondly, and independent of the charge of circularity, it is shown that the basis upon which Rayfield draws the true‐correct distinction leads to certain unacceptable consequences for action theory.

Although echocardiographic analysis reliably diagnoses idiopathic hypertrophic subaortic stenosis by detection of systolic forward anterior mitral valve motion and estimates severity of obstruction by the timed mitral encroachment of the interventricular septum, echographic stenosis may occur without hemodynamic obstruction or pressure gradient across the left ventricular outflow tract. Demonstration and mechanism of this apparent inconsistency are described in three patients with a previously unrecognized state of Idiopathic hypertrophic subaortic stenosis characterized by marked systolic forward movement of the anterior mitral valve without a simultaneous intraventricular pressure gradient, resulting from uneven septal apposition by the anterior leaflet. Echographic obstruction indexes (40, 34 and 31) during cardiac catheterization in the three patients were predictive of respective peak gradients of 37, 25 and 20 mm Hg. The horizontal nonparallel mitralseptal contact consistent with severe systolic forward movement of the anterior mitral valve in the absence of hemodynamic stenosis is believed to be caused by markedly forward displacement of the anterior papillary muscle, so that its chordae tendineae produce greater tension on the posteromedial aspect of the anterior mitral valve. Thereby the posterior portion of the leaflet is pulled forward more than its anterior side, allowing marked systolic forward anterior mitral valve motion without a pressure gradient in idiopathic hypertrophic subaortic stenosis.

Three rats received unmodifiable tailshock at random intervals in a shuttlebox. In a continuous-choice situation, Ss could choose between an auditory signal immediately preceding or immediately following the tailshock. Over repeated daily 3-h sessions, each S acquired a spatial discrimination indicating a strong preference for the signal preceding tailshock. This preference continued undiminished through two successive reversals of the position associated with signaled shock. This demonstration precludes explanations of the preference-for-signaled-shock phenomenon based upon primary reinforcement value or acquired value of the signal, position preferences, and overt modification of the aversiveness of the reinforcer through such means as postural adjustments. An explanation of recent failures to obtain the preference-for-signaled-shock effect is offered.

Infestations, populations and distribution of Steatonyssus occidentalis (Ewing) infesting the big brown Eptesicus ftucus , were studied. Adult and immature bats were collected from an attic colony at State College, Pennsylvania, in April and July 1972. All of the adult bats were infested with mites. Mean mite density per adult bat was 5 mites in April and 60 mites in July. In July, 95% of the immature bats were infested with S. occidentalis at a mean density of 30 mites per individual. Mite population structure seemed to be influenced by the maturity of host. The ratio of adult mites to nymphs was nearly 1:1 for adult hosts and approximately 1:5 for immature hosts. S. occidentalis adults and nymphs were randomly distributed on the fur-bearing portions of the adult bats, but were aggregated in the axillary and inguinal regions of the immature bats. The differences in infestation rates, mite densities, population structures, and topographic distributions which were observed between adult and immature hosts were related largely to fur development. The visual examination method of ectoparasite collection detected only 73% of the mites on adult bats but 91% of the mites on the immature hosts.

Old female mice of the SWV strain have an hereditary polydipsia–polyuria defect with a severe increase in water turnover and with hypotonic urine which contains no glucose, blood, or protein; that is, they have diabetes insipidus. Their responses to exogenous vasopressin (negative) and water deprivation (positive) and the normal amount of neurosecretory material in their posterior pituitaries indicate that they have nephrogenic diabetes insipidus. The females also have a progressive kidney defect which, although it resembles nephronophthisis in some aspects and hypokalemia in others, is unique. There is a progressive anemia. Amyloid kidneys, polycystic kidneys, diabetes mellitus, and nephronophthisis have been ruled out as the cause of the defect but hypokalemia and hypercalcemia are still possibilities. The SWV males have a milder form of the defect which develops at an older age and shows no signs of histopathology.

RNA- and reverse transcriptase (R.T.)-containing viruses have been etiologically related to leukemia in several species of animals. There is no convincing report of isolation of a similar virus from man. In the past few years, however, biochemical evidence for three components thought to be characteristic of type C viruses has been detected in human acute leukemic cells. This includes the following: 1) An enzyme with physical and biochemical properties so far indistinguishable from viral R.T. has been purified from these cells. It was also recently shown that this enzyme is immunologically closely related to R.T. purified from type C primate RNA tumor viruses, much less to murine virus R.T., and not at all to avian or feline. 2) RNA has been detected in these cells with some nucleotide sequence relatedness to the genomic RNA of some murine and primate type-C viruses. 3) The DNA product of the endogenous R.T. of human leukemic cells has nucleotide sequences related to murine and especially primate type C sarcoma viruses. Thus, certain virus-like components exist in human leukemic cells in a functional form within ribonucleoprotein particles which resemble animal type C viruses. However, if they represent virus, they are defective—not released under ordinary conditions—and a causal relationship to human neoplasia, if any, has not been shown and may be impossible to prove.

Recently, several methodological critiques have pointed out that most experiments in verbal learning fail to present statistical evidence that their results could be replicated using a different sample of language materials. Consequently, many of the studies have little scientific point because their conclusions have to be restricted to the specific language items used in the experiment. All these critiques are summarized, the various solutions to the problem are evaluated, and procedures to arrive at the simplest solution are described. This solution should present no difficulties to anyone who has had a course in analysis of variance.

An autosomal recessive mutant (symbol, dan) in the dog causes chondrodysplastic dwarfism and mild anemia as pleiotropic effects. The anemia is characterized by stomatocytosis, macrocytosis, low MCHC, increased osmotic fragility, shortened red cell survival, reticulocytosis, erythroid hyperplasia, and increased iron turnover. Minor changes can be detected in the red cells of heterozygous carriers of the dan gene, but red cell survival is normal and chondrodysplasia is not present. Red cell sodium concentration and water content are increased in anemic dogs and to a lesser degree in carriers. Glutathione deficiency is present. The disorder described here resembles a number of human hemolytic anemias with stomatocytosis, glutathione deficiency, and disordered red cell cation and water content, and further study of the dan mutant, together with investigations of the hereditary human conditions, will elucidate the maintenance of normal red cell cation balance.

Regenerative processes were defined and investigated by Smith [12]. These processes have limiting distributions under very mild regularity conditions. In certain applications, such as shot-noise processes and some queueing problems, it is of interest to consider path-functionals of regenerative processes. We seek to extend the nice asymptotic properties of regenerative processes to path-functionals of regenerative processes. We show that these more general processes converge to a “steady-state” process in a certain weak sense. This is applied to show convergence of shot-noise processes. We also present a Blackwell theorem for path-functionals of regenerative processes.

A question now being asked in many states is whether the property tax is too burdensome and whether it should be displaced by another tax. Many states have lowered property taxes on specific classes of property, while other states are considering more widespread relief from property taxes. If property taxes are reduced, other taxes will have to be increased in order to offset reductions in government revenues. What is the effect of substituting one tax for another; who will pay more and who will pay less if property taxes are decreased and sales or income taxes increased? Will overall regressiveness of taxes be reduced by substitution? The basic technique of sampling and analysis presented here hopefully will be applicable in many states and will provide important answers to these questions.

An infant with Klippel Trenaunay Syndrome (KTS), a disorder of embryonic development characterized by hemangiomas and hypertrophy of lower extremities, had bilateral nephroblastomatosis diagnosed at 1 year of age. Although the natural course of these tumors is uncertain, lesions of this kind have been suggested as the source of Wilms' tumor. In addition, foci of primitive cells suggested malignant potential. The more extensively involved kidney was removed and the contralateral lesion was treated by irradiation, actinomycin D, and vincristine, resulting in disappearance of the lesions 6 months later. The association of nephroblastic tumors with soft tissue growth disorders is extended to include KTS, and the possible relationship of nephroblastomatosis to Wilms' tumor is discussed.

Summary The effects of counterattitudinal communication behavior on latitudes of acceptance have not been empirically demonstrated. Moreover, previous research has only compared latitude of acceptance scores of highly polarized people to people holding moderate views on a controversial social issue. There were 106 college subjects used in this study. Highly polarized people were compared to others whose attitudes had moderated as a result of experimental manipulations. Although there were dramatic shifts in prime attitudes among the experimental groups, there were no differences on latitude of acceptance scores as people's attitudes moderated.

The proliferation of color television sets in American homes in the last five years suggests that the monochrome receiver may soon meet a fate similar to that of the 78 rpm phonograph record. Meanwhile, the transitional state in home television viewing-from monochrome to color-has made it possible to design a study to investigate 1) the relative effectiveness of color and monochrome school presentations on affective learning among elementary school children and 2) the relationship between the predominant home viewing mode and the measures of affective learning from the school presentations. As a result of film studies by A. W. VanderMeer (1954), we know that students, when given a choice, would rather view a color presentation than one in black-and-white. These and other studies, most of which were reviewed by Kanner (1968), disclosed that cognitive learning was not helped by color. Indeed, there were instances in which monochrome fared somewhat better. REVIEW OF RESEARCH

[ 3 H]DNA copies of avian, feline, murine, and primate RNA tumor virus genomes were synthesized in vitro by an RNA-dependent DNA polymerase reaction. These DNAs were hybridized to 60-70S RNA that had been purified from the viruses. The amount of the [ 3 H]DNA hybridized yielded a measure of the genetic relatedness among the DNA preparations synthesized by the viruses. When many combinations of DNA and RNA were analyzed, the pattern of hybridization showed in some cases that the DNA copies of the viral RNA were related to each other in the same way that the natural hosts of the viruses are phylogenetically related. This pattern was observed only among the RNA leukemia viruses. The sarcoma component in sarcoma-leukemia viruses from rats and primates appeared to be unusually closely related. The mouse mammary carcinoma virus and two unclassified viruses (MPMV and Visna) appeared to be genetically distinct. A similar analysis of DNA synthesized by an RNA-dependent DNA polymerase associated with a viral-like particle obtained from the cytoplasm of human leukemic white blood cells demonstrated that this DNA occupied a space in the affinity pattern of leukemia viruses which is expected of a nucleic acid from a primate-type-C RNA tumor virus. This observation strengthens earlier evidence that components of RNA tumor viruses are associated with human leukemia.

The composition of planar bilayers formed from a solution of glyceryl monooleate (gmo) and oleic acid (ol) in decane has been determined. In parallel, the composition of monolayers obtained by equilibrium spreading from a decane solution containing different ratios of gmo and ol has also been determined. The influence of interacting copolypeptide of l -lysine/ l -phenylalanine (1.4:1) on the monolayer composition was studied. The interaction between different basic polypeptides and surface layers composed of gmo and ol was also investigated by measuring the surface radioactivity of the polypeptides labeled by methylation of the e amino groups of lysine with 14 CH 3 I. The adherance to the lipid surface layer is augmented by increasing its negative charge and the hydrophobicity of the interacting basic polypeptides. The copolypeptide of l -lysine/ l -phenylalanine tends to adsorb more strongly than polylysine, which adsorbs slightly more than the copolypeptide of l -lysine/ l -serine. The correlation between the tendency of the polypeptides to interact with lipid layers and their modifying potency of lipid bilayers has been discussed.

This study compares the predictive capabilities of readability formulas derived from the scores and passages of two types of original criterion tests: a multiple- choice reading comprehension test and a Cloze reading comprehension test.

This paper introduces and illustrates an efficient algorithm, called the sweep algorithm, for solving medium- as well as large-scale vehicle-dispatch problems with load and distance constraints for each vehicle. The locations that are used to make up each route are determined according to the polar-coordinate angle for each location. An iterative procedure is then used to improve the total distance traveled over all routes. The algorithm has the feature that the amount of computation required increases linearly with the number of locations if the average number of locations for each route remains relatively constant. For example, if the average number of locations per route is 7.5, the algorithm takes approximately 75 seconds to solve a 75-location problem on an IBM 360/67 and approximately 115 seconds to solve a 100-location problem. In contrast, the time to solve a problem with a fixed number of locations increases quadratically with the average number of locations per route. The sweep algorithm generally produces results that are significantly better than those produced by Gaskell's savings approach and are generally slightly better than Christofides and Eilon's results; however, the sweep algorithm is not as computationally efficient as Gaskell's and is slightly less so than Christofides and Eilon's.

In order to study the enzymatic activity of adsorbed and spread monolayers of trypsin, its adsorption isotherm and spreading tendency have been determined using radioactively labelled trypsin. The labelling of trypsin by acetylation did not affect its biological activity and neither did it appreciably alter its surface activity. The enzymatic activity of trypsin spread on the adsorbed surface layers was considerably lower than its activity in the bulk phase. The activity decreased with decreasing surface concentration and with added spreading agent, e.g. isopropanol. Displacement of the enzyme from the surface by the highly surface-active substrate did not recover its biological activity. These experiments, together with the measured dependence of surface tension on protein concentration, indicate very strongly that the major part of the trypsin in the surface layer is irreversibly adsorbed and that its tertiary structure is substantially altered.

9(10)-Carboxyoctadecylamine (I) and 9(10)-aminomethyloctadecanoic acid (II) have been prepared from selectively hydroformylated oleonitrile and oleic acid, respectively. Polymerization of I gave a transparent hard, somewhat brittle, polyamide, whereas polymerization of II gave a soft, rubbery polymer that flowed slowly at room temperature. Copolymers of I with II had properties reflecting those of the component homopolymers, although II exercised a disproportionate softening effect. The same was generally true of copolymers of I or II with nylon-66 salt, caprolactam, and 9-aminononanoic acid. The copolymer of I with 25 mole % nylon-66 salt was transparent, was also elastic, and could be either drawn into fibers or made into a coherent film. The properties of the two amino acids and of their polymers agreed with those expected from simpler alkyl-substituted amino acids.

Experiments on a compartment model into which very large errors have been deliberately introduced show that sensitivity analysis continues to provide valid information about the relative importance of parameters long after other aspects of realism have been destroyed. Thus, sensitivity analysis may be the first area in which a mathematical model yields meaningful information as it progresses through its formulation and development stages, and data-base refinement may be started relatively early in the modelling process.