Showing papers by "Rutgers University published in 1973"
TL;DR: A method is described to obtain brush border,i.e. microvillus membranes, from human intestinal epithelial cells based on the sequential use of CaCl2, differential centrifugation and Tris, characterized by a high specific activity in brush border membrane markers as well as its appearance on electron micrographs.
752 citations
TL;DR: The results suggest that hydroxylated proline increases the thermal stability of collagen.
549 citations
Book•
01 Jan 1973501 citations
498 citations
TL;DR: Canids and felids are compared regarding evolutionary history, distribution, habitat preferences, morphology and behaviour, factors permitting and promoting sociality in both families are discussed, and communication mechanisms within each sensory modality compared.
364 citations
TL;DR: Seven DNA methylation mutants isolated from Escherichia coli K-12 were defective in their ability to restrict lambda and none of the mutations had the effect of being lethal.
Abstract: Fourteen deoxyribonucleic acid (DNA) and 10 ribonucleic acid (RNA) methylation mutants were isolated from Escherichia coli K-12 by examining the ability of nucleic acids prepared from clones of unselected mutagenized cells to accept methyl groups from wild-type crude extract. Eleven of the DNA methylation mutants were deficient in 5-methylcytosine (5-MeC) and were designated Dcm. Three DNA methylation mutants were deficient in N6-methyladenine (N6-MeA) and were designated Dam. Extracts of the mutants were tested for DNA-cytosine:S-adenosylmethionine and DNA-adenine:S-adenosylmethionine methyltransferase activities. With one exception, all of the mutants had reduced or absent activity. A representative Dcm mutation was located at 36 to 37 min and a representative Dam mutation was located in the 60-to 66-min region on the genetic map. The Dcm mutants had no obvious associated phenotypic abnormality. The Dam mutants were defective in their ability to restrict λ. None of the mutations had the effect of being lethal.
344 citations
TL;DR: In this experimental system, prey became food—limited at their peak density, resulting in limit cycle oscillations of predator and prey at approximately constant amplitude, which did not result from the introduction of refuges or physical complexity.
Abstract: Previous attempts at the prolonged laboratory study of predator—prey systems lacking refuges or physical complexity have been unsuccessful. The addition of Methyl Cellulose to interacting laboratory populations of Paramecium aurelia and its predator, Didinium nasutum, prolongs coexistence by reducing the frequency of contact between predator and prey. The study of this system under controlled conditions revealed the perturbing influence of a time delay in the predator population that resulted in oscillations of increasing amplitude terminating with D. nasutum's extinction. Enrichment of the system by supplying excess bacteria resulted in the extinction of P. aurelia. The perturbing effect of D. nasutum's time delay was counteracted by reducing the amount of bacterial food for Paramecium. In this system, prey became food—limited at their peak density, resulting in limit cycle oscillations of predator and prey at approximately constant amplitude. The medium used for these experiments lack physical inconsistencies that might act as barriers to movement and did not provide the prey with a superior dispersal ability. Coexistence of the predator and prey in this experimental system did not result from the introduction of refuges or physical complexity.
310 citations
TL;DR: Rats maintained on an intermittent food schedule with an available ethanol solution drink to excess approximates a model of human alcoholism, resulting in unequivocal physical dependence.
Abstract: Rats maintained on an intermittent food schedule with an available ethanol solution drink to excess (13.1 grams of ethanol per kilogram of body weight, daily). Removal of ethanol produces symptoms of physical dependence including death from tonic-clonic seizures. Overindulgence in oral self-administration of an aqueous ethanol solution, resulting in unequivocal physical dependence, approximates a model of human alcoholism.
254 citations
TL;DR: Seven criteria for an animal model are proposed including the oral ingestion of alcohol without food deprivation, substantial ingestion of Alcohol, the performance of work to obtain alcohol, the maintenance of intoxication over a long period and, finally, the production of physical dependence and, on withdrawal, the abstinence syndrome.
Abstract: A correspondence between the various components of human alcoholism and their animal analogue has not yet been achieved; in some part, this failure resides with experimental attempts which obtain which obtain only surface equivalencies and which lack an underlying motivational structure. Seven criteria for an animal model are proposed including the oral ingestion of alcohol without food deprivation, substantial ingestion of alcohol with competing fluids available, drinking directed to the intoxicating effect of alcohol, the performance of work to obtain alcohol, the maintenance of intoxication over a long period and, finally, the production of physical dependence and, on withdrawal, the abstinence syndrome.
253 citations
TL;DR: This chapter describes the experimental situation and procedures that are common to all of the studies of delayed matching and short-term memory in monkeys, which are capuchin monkeys who, before their paradigm delayed matching-to-sample (DMTS) experience, are in laboratory residence from one to four years.
Abstract: Publisher Summary Delayed matching can be dramatically facilitated by the simple operation of extinguishing all illumination during the delay (retention) interval. This chapter describes the experimental situation and procedures that are common to all of the studies of delayed matching and short-term memory in monkeys. All experimental subjects are capuchin monkeys (Cebus apella) who, before their paradigm delayed matching-to-sample (DMTS) experience, are in laboratory residence from one to four years, during which they were exposed to various kinds of experimental training. Motivation is induced by food deprivation, the animals being reduced to a body weight at which they work with reasonable diligence. After completing 15 responses on the microswitch, one of the stimuli (the sample) appears on the center projector and remains there until the subject pressed the center key for a minimum duration of 0.3 seconds. The sample then disappears and the delay (retention) interval begins.
243 citations
TL;DR: Three-dimensional models constructed from 80 to 150 consecutive serial sections of entire yeast cells showed that all the separate mitochondrial profiles were cross sections through a single, branching, tubular structure about 50 to 60 micrometers in length and 200 to 600 nanometers in diameter.
Abstract: Three-dimensional models constructed from 80 to 150 consecutive serial sections of entire yeast cells showed that all the separate mitochondrial profiles were cross sections through a single, branching, tubular structure about 50 to 60 micrometers in length and 200 to 600 nanometers in diameter. The data are contrary to conventional notions of mitochondrial size, form, and number per cell and should lead to a reassessment of mitochondrial genetics and biogenesis.
TL;DR: In this paper, a geometric model of preference is described for evaluating choices in decomposed two-choice experimental games, which characterizes a subject's choice behavior in terms of a parameter, called motivational orientation, that represents the relative weights assigned by S to his own and to the other player's outcomes.
Abstract: A geometric model of preference is described for evaluating choices in decomposed two-choice experimental games. The model characterizes a subject's (S's) choice behavior in terms of a parameter, called motivational orientation, that represents the relative weights assigned by S to his own and to the other player's outcomes. Previous definitions of motivational orientation are shown to be included in the model as particular values of the model parameter, and the characterization of decomposed games by dominance class is interpreted geometrically. Methods for measuring motivational orientation in decomposed games are discussed, and an experiment is presented demonstrating the validity and reliability of the construct.
TL;DR: The two processes of aging and cohort succession underlie many of the changes and trends of concern to social scientists, and as the relevant data accumulate, better understanding of both individual and social change becomes more nearly attainable.
Abstract: The two processes of aging and cohort succession underlie many of the changes and trends of concern to social scientists, and as the relevant data accumulate, better understanding of both individual and social change becomes more nearly attainable. The purpose of this article is to further such understanding by providing guideposts for the analysis of data that often appear to be deceptively simple. Language: en
TL;DR: The genes responsible for DNA adeninemethylation (dam) and DNA cytosine methylation (dcm) have been mapped on the E. coli K-12 genetic map and are recessive in F′ merodiploids.
Abstract: The genes responsible for DNA adenine methylation (dam) and DNA cytosine methylation (dcm) have been mapped on the E. coli K-12 genetic map. The dam gene is situated at min 65 and the gene order cysG-(trpS, dam)-aro B inferred. The dcm gene is located at min 37.5 and the gene order is supD-dcm-flaA1. In F′ merodiploids, the dam and dcm alleles are recessive.
TL;DR: The elastic constants of a hard-rod liquid crystal are calculated using the Onsager theory as discussed by the authors, with results similar to those given by Priest, and the elastic constants are shown to be tight.
Abstract: The elastic constants of a hard-rod liquid crystal are calculated using the Onsager theory, with results similar to those given by Priest.
TL;DR: In this article, the authors obtained conditions on T, D, and X which would guarantee the strong convergence and weak convergence of the iterates to a fixed point of T in D and X in X, respectively.
TL;DR: Lordosis in response to manual palpation of the flanks and perineum was markedly facilitated by simultaneously probing the vaginal cervix, and intensity and probability of occurrence varied significantly in relation to the estrous cycle.
Abstract: Lordosis in response to manual palpation of the flanks and perineum was markedly facilitated by simultaneously probing the vaginal cervix. While palpation without cervical probing never induced lordosis in 96 ovariectomized, hormone-untreated rats, addition of cervical probing induced lordosis in 48% of these individuals. Cervical probing alone never induced lordosis. Estrogen administration (as little as a single injection of 1.0 μg/100 g body wt) significantly increased the intensity (extent of dorsiflexion, measured photographically), and probability of occurrence, of lordosis in response to palpation with cervical probing. Lordosis in response to mounting attempts by males, or by palpation alone, occurred only rarely at estrogen dosages lower than 10.0 μg/100 g body wt. Lordosis intensity and probability of occurrence varied significantly in relation to the estrous cycle; they were higher in proestrus and the transitional periods of diestrus-proestrus and proestrus-estrus, than in estrus, metestrus or...
TL;DR: In this article, the importance of training clients to emit loving and caring responses is emphasized, while ignoring the negative aspects of anger and attacking behaviors, and emphasizing the virtues of positive reinforcement in this context.
TL;DR: This paper found that these magnitude estimations were assimilated toward the immediately preceding stimuli as far as five trials back in the sequence of stimuli, and that the ratio judgments were consistently asymmetric and the data displayed a form of time order error.
Abstract: Twelve Ss made magnitude estimations of the loudness of each one of a sequence of pure tones according to the rule R(N) = R(N - 1) · [S(N)/S(N - 1)], where R(N) is the response on Trial N, R(N - 1) is the response on Trial N - 1, and S(N)/S(N - 1) is the judged ratio of the “loudness” of the pure tone presented on Trial N to that of the pure tone presented on Trial N - 1. It was found that these magnitude estimations were assimilated toward the immediately preceding stimuli as far as five trials back in the sequence of stimuli. In addition, ratio judgments were consistently asymmetric and the data displayed a form of “time order error.” In all cases, there are similar effects displayed in category judgment data. These and other data imply that at least some kinds of magnitude estimations may involve a judgment of the “difference” or “distance” between pairs of stimuli as a first step in the production of the response required by the judgment situation.
TL;DR: The necessary and sufficient conditions for achieving long-lasting therapeutic change are examined and the rationale for recommending direct intervention across seven distinct but inter-related modalities is outlined in some detail.
Abstract: This paper examines the necessary and sufficient conditions for achieving long-lasting therapeutic change. The rationale for recommending direct intervention across seven distinct but inter-related modalities is outlined in some detail. Other systems of psychotherapy are briefly compared to the mult
TL;DR: Leucocytes obtained from a donor sensitive to Candida antigen contain a factor (transfer factor) which transfers this sensitivity to non-sensitive recipients and this material is present in the dialysate of leucocyte lysates and can be purified therefrom by gel filtration.
TL;DR: Macrophages suppress incorporation of thymidine (TdR) by nonadherent spleen, thymus and bone marrow cells, in most instances, to less than 5% of that observed in culture to which macrophages were not added.
TL;DR: Alcohol in nonintoxicating doses elicits a depression of cardiovascular function in normal unhabituated subjects.
Abstract: Depression of myocardial contractility after ethanol ingestion in man has previously been shown only in patients with heart disease. In the present study, normal subjects, aged 23-30 years, ingested six ounces of 43% alcohol over a two hour period (Group I, 6 subjects) or a one hour period (Group II, 5 subjects). Systolic time intervals were measured every 15 min from simultaneous ECG, phonocardiogram and carotid pulse tracings. Heart rate, total electromechanical systole and left ventricular ejection time (LVET) were not changed at any time from pre-alcohol values and, except for a small (5 mm Hg) and transient change in diastolic pressure in Group II, aortic pressures also were unchanged. However, in Group I, after 60 min, at a blood ethanol of 74 ± 3 mg%, left ventricular depression was manifested by increased pre-ejection period (PEP) from 90 ± 2 to 96 ± 3.1 msec, isovolumic time (IVT) from 44 ± 3.5 to 52 ± 4 (P < .01), and PEP/LVET ratio from 0.299 ± 0.009 to 0.323 ± 0.01 (P < .05). Further depressio...
TL;DR: It is demonstrated that in each ghost-free dual model with one minor restriction, there exists a critical dimensionality of space-time in which the pomeron singularity becomes a factorizable Regge pole.
TL;DR: Kidney Cd increased with dietary Cd level but appeared to reach a near maximal level in the 450 and 1350 ppm Cd groups, and renal Cd content was directly related to the level of cadmium-binding protein isolated from kidney cortex by gel filtration chromatography.
Abstract: Cadmium (Cd) as cadmium chloride was added to the basal diet of 8-week-old swine at levels of 0, 50, 150, 450 and 1350 ppm for a 6-week comparison period. Growth rate was decreased as a function of Cd level, having ceased in the 1350 ppm group. Hematocrit values were the most sensitive measurement of toxicity and were decreased in all Cd-fed animals. Serum phosphorus was decreased in animals receiving 450 and 1350 ppm Cd, while serum calcium was not affected by Cd intake. Bone ash content was decreased as a function of Cd intake. Leucine aminopeptidase (LAP) activity was depressed in renal cortex from the groups receiving 150 ppm Cd or more, but serum LAP was unaffected by Cd intake. The kidney, liver, spleen and teeth contained the highest concentrations of Cd. Kidney Cd increased with dietary Cd level but appeared to reach a near maximal level in the 450 and 1350 ppm Cd groups. This renal Cd content was directly related to the level of cadmium-binding protein isolated from kidney cortex by gel filtration chromatography. 30 references, 2 figures, 6 tables.
TL;DR: Parachlorophenylalanine was found to increase overall levels of startle amplitude, and this effect was entirely due to an attenuation of the rate of habituation.
Abstract: The effect of parachlorophenylalanine (PCPA), and the presumed depletion of serotonin due to it, was studied for its effect on the habituation of a startle response in rats. Parachlorophenylalanine was found to increase overall levels of startle amplitude. Detailed examination of the data from individual animals indicated that this effect was entirely due to an attenuation of the rate of habituation.
TL;DR: In this paper, some fixed point theorems were developed and applied to the question of existence of nontrivial periodic solutions of nonlinear, autonomous functional differential equations, and the standard results of G. S. Jones and R. B. Grafton can be obtained by their methods, and they prove periodicity results for some equations, for instance a neutral functional differential equation.