Showing papers by "University of Massachusetts Amherst published in 1976"
TL;DR: In this paper, a detailed mineralogical and chemical investigation of shale cuttings from a well (Case Western Reserve University Gulf Coast 6) in Oligocene-Miocene sediment of the Gulf Coast of the United States was made by x-ray diffraction.
Abstract: A detailed mineralogical and chemical investigation has been made of shale cuttings from a well (Case Western Reserve University Gulf Coast 6) in Oligocene-Miocene sediment of the Gulf Coast of the United States. The 10-µm fractions from the 1,250- to 5,500-m stratigraphic interval were analyzed by x-ray diffraction. Major mineralogic changes with depth take place over the interval 2,000 to 3,700 m, after which no significant changes are detectable. The most abundant mineral, illite/smectite, undergoes a conversion from less than 20 percent to about 80 percent illite layers over this interval, after which the proportion of illite layers remains constant. Over the same interval, calcite decreases from about 20 percent of the rock to almost zero, disappearing from progressively larger size fractions with increasing depth; potassium feldspar (but not albite) decreases to zero; and chlorite appears to increase in amount. Variations in the bulk chemical composition of the shale with depth show only minor changes, except for a marked decrease in CaO concomitant with the decrease in calcite. By contrast, the <0.1-µm fraction (virtually pure illite/smectite) shows a large increase in K2O and Al2O3 and a decrease in SiO2 The atomic proportions closely approximate the reaction smectite + Al+3 + K+ = illite + Si+4. The potassium and aluminum appear to be derived from the decomposition of potassium feldspar (and mica?), and the excess silicon probably forms quartz. We interpret all the major mineralogical and chemical changes as the response of the shale to burial metamorphism and conclude that the shale acted as a closed system for all components except H2O, CaO, Na2O, and CO2. Compositional changes in the shale as a function of metamorphic grade closely parallel compositional changes in shale as a function of geologic age.
1,328 citations
1,109 citations
TL;DR: A system that attempts to generate test data for programs written in ANSI Fortran by symbolically executing the path and creating a set of constraints on the program's input variables, which facilitates error detection and being a possible aid in assertion generation and automatic program documentation.
Abstract: This paper describes a system that attempts to generate test data for programs written in ANSI Fortran. Given a path, the system symbolically executes the path and creates a set of constraints on the program's input variables. If the set of constraints is linear, linear programming techniques are employed to obtain a solution. A solution to the set of constraints is test data that will drive execution down the given path. If it can be determined that the set of constraints is inconsistent, then the given path is shown to be nonexecutable. To increase the chance of detecting some of the more common programming errors, artificial constraints are temporarily created that simulate error conditions and then an attempt is made to solve each augmented set of constraints. A symbolic representation of the program's output variables in terms of the program's input variables is also created. The symbolic representation is in a human readable form that facilitates error detection as well as being a possible aid in assertion generation and automatic program documentation.
801 citations
540 citations
TL;DR: In this paper, the authors considered the marriage relationship as a special case of pair relationships in general, and its cohesiveness was interpreted according to concepts drawn from Lewinian field theory.
Abstract: The marriage relationship is considered as a special case of pair relationships in general, and its cohesiveness is interpreted according to concepts drawn from Lewinian field theory. The hypothetical constructs of “attraction” and “barrier” forces, as well as contrasting “alternative attractions,” are used to organize the research literature on the determinants of marital stability and dissolution.
444 citations
TL;DR: A straightforward relationship between the nitrate concentration of outer leaves of head lettuce and the amounts of fertilizer-nitrite applied within a given planting date and nitrite source is presented in this paper.
Abstract: Publisher Summary This chapter focuses on the accumulation of nitrate in vegetable crops, which is a natural phenomenon resulting from uptake of the nitrate ion in excess of its reduction and subsequent assimilation. Accumulation of nitrate is dependent on and related to the genetic makeup of the plant, the nitrate supplying-power of the soil, and the environmental conditions under which the plant is grown. The chapter focusses on the hazards of nitrate and nitrite to human health. Factors affecting nitrate accumulation are discussed. A straightforward relationship between the nitrate concentration of outer leaves of head lettuce and the amounts of fertilizer-nitrite applied within a given planting date and nitrite source is presented. The chapter concludes by examining nitrate concentrations in vegetables. Nitrate concentrations are lowest in floral parts and increasing concentrations are found in fruit or grain, leaves, roots, and petioles or stems.
364 citations
TL;DR: An ideal weight-control drug would be one that acts on neural weight-regulating systems to lower body weight set-point without being estrogenic or anti-estrogenic in other hormone-sensitive systems.
Abstract: Publisher Summary Sex and reproductive condition often have very dramatic effects on the behaviors, affecting body weight and composition in a wide variety of species, although most of the experimental work has been performed with rats. Gonadal steroids also affect behavioral and physiological regulation of body weight. A great deal of descriptive research and simple endocrinological approaches have given a good idea of how regulatory behaviors and body weight fluctuate with variations in reproductive status and which hormones are responsible for these fluctuations. A variety of factors, including diet palatability, environmental temperature, relative levels of various metabolic hormones, and the opportunity to exercise in running wheels, affect body weight level in rats. Several kinds of neurological damage may also raise or lower body weight set-point. Animals expend calories in a wide variety of ways, but the two principal sources of energy loss (and the two most affected by behavior) are exercise and heat loss to the environment. In female rats, estradiol is the principal ovarian steroid influencing behavioral regulation of energy balance, as well as progesterone also affects weight regulation in female rats. An estrogen-like compound could be used to lower body weight and combat obesity in human being. An ideal weight-control drug would be one that acts on neural weight-regulating systems to lower body weight set-point without being estrogenic or anti-estrogenic in other hormone-sensitive systems. Food intake is linked to sex hormone secretion to ensure that eating and energy stores will increase during pregnancy, and the fluctuations during estrous cycles are simply a by-product of this association.
280 citations
TL;DR: The results suggest that the transient changes in food intake caused by estradiol withdrawal and replacement are accomplished by permanent changes in meal size followed by compensatory changes in the number of meals consumed per day.
268 citations
TL;DR: A cluster analytic approach was used to determine possible age differences in the structure of personality as measured by the Cattell Sixteen Personality Factor Questionnaire, and a third cluster dimension, interpreted as openness to experience, showed age-related differences.
Abstract: A cluster analytic approach was used to determine possible age differences in the structure of personality as measured by the Cattell Sixteen Personality Factor Questionnaire. Subjects were 969 adult male volunteers, originally divided into three groups: 25 to 34, 35 to 54, and 55 to 82. Two familiar dimensions of personality, Anxiety-Adjustment and Introversion-Extraversion, were found to be cross sectionally stable. A third cluster dimension, interpreted as openness to experience, showed age-related differences. Young subjects showed openness to feelings; middle-aged subjects showed openness to ideas; and old subjects showed a balanced openness to both feelings and ideas. Repartitioning of the sample into two groups (ages 25 to 43 and 44 to 82), and three groups (25 to 39, 40 to 47, and 48 to 82) confirmed these age differences in the third cluster. The interpretation of the third cluster is discussed in terms of Jung's concepts of psychological functions.
228 citations
TL;DR: In this paper, low-angle x-ray scattering and small-angle light scattering were analyzed using the Tsvankin-Buchanan technique and led to values of the repeat period of the lamellar structure and the thickness of the crystalline and amorphous layers.
Abstract: Solvent-cast films of blends of poly(ϵ-caprolactone) (PCL) with poly(vinyl chloride) (PVC) were examined by low-angle x-ray scattering and by small-angle light scattering. X-ray scattering from crystalline compositions were analyzed using the Tsvankin–Buchanan technique and led to values of the repeat period of the lamellar structure and the thickness of the crystalline and amorphous layers. With increasing content of PVC, the amorphous layer thickness increased sufficiently to accommodate the PVC, leading to values of the linear crystallinity consistent with macroscopic measurements by density and DSC techniques up to about 50% PVC by weight. Above this concentration, the lamellar structure no longer appeared to be volume filling. At high concentration of PCL, the polymer consisted of volume-filling spherulites containing the lamellar substructure. Spherulite sizes were measured by light scattering and absolute light scattering intensities were consistent with calculations based upon the degree of crystallinity and anisotropy of the spherulites. Compositions containing more than 60% PVC were amorphous. Low-angle x-ray scattering was interpreted in terms of the Debye–Bueche theory which leads to values for a correlation distance lc and the mean-square electron density fluctuation 〈η2〉 (which was also obtained from the invariant). By the method of Porod, the correlation distances were resolved into persistence lengths within the two phases, which were determined as a function of composition. The fluctuation 〈η2〉 was analyzed in terms of a two-phase model to show that its value was somewhat larger than would be obtained if the phases were composed of the pure components. It was not possible to uniquely determine their compositions. The data were consistent with the existence of a transition zone of the order of 30 A thick between phases.
218 citations
TL;DR: Evidence is presented which suggests that the particles are an in vivo structural repeating unit of deoxyribonucleoprotein, and not a preparation-induced artefact.
TL;DR: A behavioral study utilizing an attitudinal model explored the relationships between management information system users' perceptions of their computer system, perceived variables exogenous to the system, and the impact of external factors on these perceptions.
Abstract: A behavioral study utilizing an attitudinal model explored the relationships between management information system users' perceptions of their computer system, perceived variables exogenous to the ...
TL;DR: In this article, a set of rigorous, broadly applicable equations for effective heat capacity during the freezing and thawing of foods and biological materials were derived based on a modified form of the freezing point depression equation.
Abstract: Based on a modified form of the freezing point depression equation we have derived a set of rigorous, broadly applicable equations for effective heat capacity during the freezing and thawing of foods and biological materials. The equations have been integrated with respect to temperature, thereby providing a set of useful equations for enthalpy during freezing and thawing. The validity and utility of the equations are demonstrated using data from the literature. Methods for adjusting the equations to account for changes in water content and fat content are presented. The enthalpy equations are useful for calculating heat-transfer loads during freezing and thawing, and the heat capacity equations can be advantageously used in differential equations for calculating freezing and thawing heat-transfer rates.
TL;DR: In this article, it was shown that probability amplitudes and transition matrix elements are gauge-invariant for a nonrelativistic spinless, spinless charged particle.
TL;DR: In this article, the authors investigated the relationship between coliform and streptococcus density in waste discharges and receiving waters, and found that coliforms were denser in discharge discharges than in receiving waters.
Abstract: (1976). Fecal coliform and fecal streptococcus density relationships in waste discharges and receiving waters. C R C Critical Reviews in Environmental Control: Vol. 6, No. 4, pp. 349-369.
TL;DR: A theoretical framework for the exploration of processes of fusion and individuation is presented, with suggested applications for the study of problems experienced by adult couples.
Abstract: Growing interest in concepts of fusion and individuation within a number of different theoretical systems of psychotherapy suggests an emerging shift in perspective in the conceptualization of psychopathology and psychotherapy. This shift may represent a first step in the integration of individual and relational dynamic theories. A theoretical framework for the exploration of processes of fusion and individuation is presented, with suggested applications for the study of problems experienced by adult couples. The process of individuation from fusion to dialogue is outlined in the description of four modes of relationship. In this context, the paper suggests ways in which a variety of problematic relational patterns seen in couples may be viewed as reflecting the partners' struggles to move from fusion to dialogue.
TL;DR: This work has shown that an habituated stimulus may once again be able to evoke a response after the presentation of an intervening novel stimulus, and rules out sensory and motor fatigue as the bases of the response decrement.
Abstract: HABITUATION—in general defined as a reversible decrement of response to repeated stimulation—is a widely studied form of behavioural plasticity. The reversibility sets habituation apart from fatigue and accommodation. An habituated stimulus may once again be able to evoke a response after the presentation of an intervening novel stimulus. This phenomenon, known as dishabituation, rules out sensory and motor fatigue as the bases of the response decrement.
TL;DR: The earliest attempts to apply computers to the problem of understanding natural language, although entered into with great optimism, did not meet with much success as discussed by the authors, leading to the belief that a more sophisticated view of language, involving not only a dictionary and grammar but also full semantics and total knowledge of the world, was required if computers were to deal with natural language with any success.
TL;DR: Some aspects of D-amino acids in higher plants will be reviewed and it is shown how their occurrence raises interesting questions in living organisms.
TL;DR: It is shown that the shuffle-exchange interconnection network permits the efficient partitioning of an array computer into subarrays to allow for the simultaneous computation of several identical problems.
Abstract: In this paper, a control mechanism for a shuffle-exchange interconnection network of N cells is proposed. With this network it is possible to realize some important permutations in log 2 N shuffle-exchange steps. In the control mechanism presented, the control variables at step k are determined by a Boolean operation of the control variables at step k ?1. The Boolean operation is very simple so that little additional hardware is required for this computation. This control scheme requires only one bit per cell instead of a destination tag of log 2 N bits required by a control mechanism presented previously. The network can be used for the interconnection of memory modules and processors in an array computer, and for the accessing of blocks of consecutive data in large dynamic memories. It is also shown that the shuffle-exchange interconnection network permits the efficient partitioning of an array computer into subarrays to allow for the simultaneous computation of several identical problems.
TL;DR: In this article, the authors developed and analyzed a model of a particular set of real world job shops and found that workers flexibility and job routings significantly improved both performance criteria for all dispatching rules considered, with mean flow time and mean job tardiness used as performance criteria.
Abstract: This research involves the development and analysis of a model of a particular set of real world job shops. The characteristics of the process include workers flexibility and job routings which may include assembly operations. An experimental design was used which allowed statistical comparisons to be made. Various control and staffing policies were considered, with mean flow time and mean job tardiness used as performance criteria. The shortest imminent operation time rule was found to provide the best performance in all but one situation. Workforce flexibility was observed to significantly improve both performance criteria for all dispatching rules considered.
TL;DR: The results indicate that the bovine corpus luteum can synthesize progesterone in response to beta adrenergic-receptor agonists and that all progestersone production by the corpus lutesum can be inhibited by a beta adren allergic blocker.
Abstract: Catecholamine-induced stimulation of progesterone by the bovine corpus luteum in vitro was investigated. Epinephrine norepinephrine and isoproterenol each caused significant (p less than .025) stimulation of progesterone production by luteal tissue from all animals studied on Days 8-16 of the estrous cycle. Phenoxybenzamine failed to inhibit the stimulatory action of epinephrine and norepinephine. Propranolol prevented all progesterone production initiated by epinephrine norepinephrine or isoporterenol. Propranolol also inhibited luteinizing hormone-induced stimulation of progesterone. Phenoxybenzamine had no effect on the gonadotropin-induced stimulation. These results indicate that the bovine corpus luteum can synthesize progesterone in response to beta adrenergic-receptor agonists and that all progesterone production by the corpus luteum can be inhibited by a beta adrenergic blocker.
TL;DR: The vitellogenins of Hyalophora cecropia and Blattella germanica have similar Stokes' radii (69 and 75,&), sedimentation coefficients (15.9 and 16.8s), and isoelectric points (pH 5.7 and 5.0), but molecular weights, shapes and charges of the viteLLogenins are similar to non-vitellagenins and form no basis for selective uptake.
TL;DR: Songer-Nocks has questioned the generality and sufficiency of Fishbein's model of intentions as discussed by the authors, and it is shown that her conclusions reflect a basic misunderstanding of the model and its implications.
TL;DR: Scopolamine hydrobromide disrupted classical conditioning in comparison with drug controls, but had no adverse effects on habituation of the unconditioned reflex or on latent inhibition.
Abstract: Rabbits injected with scopolamine hydrobromide (1.5 mg/kg) were contrasted with control animals injected with scopolamine methylbromide or saline in terms of habituation of the unconditioned nictitating membrane response (NMR), classical defensive conditioning, and latent inhibition using auditory and visual conditioned stimuli. Scopolamine hydrobromide disrupted classical conditioning in comparison with drug controls, but had no adverse effects on habituation of the unconditioned reflex or on latent inhibition. The drug also raised thresholds of the auditory (but not visual) CS for eliciting the conditioned NMR. Results were discussed in terms of presumed cholinergiclimbic system involvement in Pavlovian conditioning and inhibition.
TL;DR: There was some suggestion that progesterone may increase colonic temperature when implanted in the preoptic area of ovariectomized rats, and estradiol benzoate in this site had no effect on Colonic temperature.
TL;DR: In this article, a two-dimensional mathematical model is developed to predict the internal behavior of power transistors operating under steady-state conditions, which includes the internal self-heating effects in the transistors and is applicable to predict transistor behavior under high current and high-voltage operating conditions.
Abstract: A two-dimensional mathematical model is developed to predict the internal behavior of power transistors operating under steady-state conditions. This model includes the internal self-heating effects in power transistors and is applicable to predict the transistor behavior under high-current and high-voltage operating conditions. The complete set of partial differential equations governing the bipolar semiconductor device behavior under nonisothermal conditions is solved by numerical techniques without assuming internal junctions and other conventional approximations. Input parameters for this model are the dimension of the device, doping profile, mobility expressions, generation-recombination model, and the boundary conditions for external contacts. Computer results of the analysis of a typical power transistor design are presented for specified operating conditions. The current density, electrostatic potential, carrier charge density, and temperature distribution plots within the transistor structure illustrate the combined effect of the electrothermal interaction, base conductivity modulation, current crowding, base pushout, space charge layer widening, and current spreading phenomena in power transistors.
TL;DR: It is suggested that iteroparity, which may have evolved in response to prolonged population decline within persistent local habitats, will also be adaptive when those habitats finally deteriorate and should alternate between short periods of rapid population growth and prolonged periods of decline.
Abstract: Hypothesis.-Tribolium castaneum is a primary colonist. Adults of this species lead a nomadic existence in which dispersal is intensive and extensive, and highly responsive to density. T. confusum is a secondary colonist. By comparison with T. castaneum, dispersal of T. confusum adults is less intensive, and less responsive to the presence of other individuals. In both species of Tribolium the tendency to disperse persists throughout adulthood. Development of the hypothesis.-Beetles of the Tenebrionid subfamily Ulominae, to which Tribolium belong, are typically associated with rotting wood and the loose bark of trees (Good, 1933). T. castaneum is apparently found in this habitat in forests of the Indian subcontinent (Good, 1933), and Sinha (1968) notes that T. castaneum and T. confusum are occasionally found separately in Canadian forests. Feral populations of Tribolium have been observed in the nests of bees and birds, and in manure (Hinton, 1948; Lefkovitch in Mertz, 1971; Jones, 1967). The beetles, however, are most abundant in warehouses where they infest stored products. Such "domestic" populations of both species show a cosmopolitan distribution. The diets of T. castaneum and T. confusum overlap broadly, and include a bewildering array of plant and animal products (Good, 1933) which need only be sufficiently soft or small in size to be eaten. Immatures and adults of both species are also predaceous and cannibalistic (Park et al., 1965). These activities are modified according to the nutritional quality of their food (Sokoloff and Lerner, 1967). To be sure, comparative nutritional studies (Sokoloff et al., 1966a, 1966b; Sinha, 1966, 1972) have documented species differences in the suitability of specific foods for development and reproduction, but, on the whole, one is impressed with the opportunistic generality in the diets of both species. These and related aspects of the biology of Tribolium are comprehensively reviewed by Sokoloff ( 1974). Tribolium habitats are undoubtedly temporary. Whether a rotting log or a sack of flour, a Tribolium habitat can be expected to support a variable number of generations before it completely deteriorates. It is not unlikely, then, that Tribolium populations should alternate between short periods of rapid population growth and prolonged periods of decline. To this characteristic Mertz (1971) attributes much of the natural selection for long reproductive life (iteroparity) in Tribolium species. If breeding habitats are widely distributed in space, a long life span would give females time to search for them (cf. Cole, 1954). If we make the reasonable assumption that persistent habitats also arise infrequently, then it follows that iteroparity, which may have evolved in response to prolonged population decline within persistent local habitats, will also be adaptive when those habitats finally deteriorate. Tribolium females produce eggs continuously. They may lay them over a wide range of habitats, each with a low probability of successfully supporting their offspring to adulthood. Such temporal and spatial uncertainty in the survival of immatures will also promote the evolution of iteroparity (Murphy, 1968). Adaptive dispersal is an element of
TL;DR: The abstract machine used to define ASPLE, the ASPLE Machine, is specified by its machine state ~ an object satisfying the predicate is-state which is defined by four predicate definitions in Table 4.1.
Abstract: Machine The abstract machine used to define ASPLE, the ASPLE Machine, is specified by its machine state ~. This is an object satisfying the predicate is-state which is defined by four predicate definitions in Table 4.1. Rule [M10] in this table: [M01] i s s tate = ((program: is-abs-program), ]abstraction of concrete program] (control: i s -abs-control) , [control of abstract maehinel (store: is-abs-storage) , ( input : i s -abs-const l i s t ) , [input file] (output : i s -abs -const l i s t ) [output file] Computing Surveys, Vol. 8, No. 2, June 1976 236 • M. Marcotty, H. F. Ledgard, and G. V. Bochmann shows that a composite object $ satisfying the predicate i s -s tate has five components: 1) program: the abstracted program to be interpreted. This component will be described in the Subsection, VDL Representation of Programs [page 237]. 2) control: the control part of the Machine. 3) store: the storage part of the Machine. 4) inpu t : the input file. 5) output : the output file. The control part determines the action of the ASPLE Machine as the abstracted program is interpreted. The object selected by control is an object that satisfies the predicate is-control . This is a stack of machine operations that will be described in the Subsection, VDL Interpreter [page 248]. The storage part of the ASPLE Machine is defined by the predicate definition [14021 : [M021 is-storage = ({ ( i d : i s a b s v a l u e ) II i s a b s i d e n t i f i e r ( i d ) } ) [each element of the set of components of the storage part is selected by an identifier and is an object satisfying is-abs-value] The notation here is similar to set notation and defines the storage part as a finite set of selector-object pairs of the form (id: is-abs-value); a selector id and an object that satisfies the predicate is-abs-value. The \"-abs-\" indicates that the object is part of the abstract machine. The latter part of the definition states that the selector id satisfies the predicate is-abs-identifier. The value part of the pair represents an object that can be obtained by applying an identifier as a selector to the storage component of the ASPLE Machine. The predicate is-abs-value is defined by the predicate definition [M03] : [Mo3] i s a b s v a l u e = i s a b s c o n s t ~ / i s a b s i d e n t i f i e r By this rule, an ASPLE value is either a constant or an identifier. The input and output files, input(G) and o u t p u t ( 0 respectively, are objects satisfying the predicate is-absconst-Iist . These objects are therefore lists of objects each element of which satisfies isabs-const . By rule [1404]: [M04] is-abs-const = i s a b s b o o l e a n V is-abs-integer an object that satisfies is-abs-const will be one that satisfies either is-abs-boolean or is-abs-integer. The second part of Table 4.1 defines the initial state of the ASPLE Machine, ~0: G0 ffi m ( ( p r o g r a m : t r a n s l a t e ( P R O G ) ) , [initialized by performing translate function on the concrete program PROG] (control: interpret-program), (store: fl ( input: [input file for program, obtained from a source outside this definition]) (output: i s ( ) ) ) [output file is initially empty] The program part of the ASPLE Machine is an abstracted ASPLE program, described in the Subsection, VDL Representation of Programs [page 237]. The program part is initialized by attaching with the selector program the object obtained by evaluating the funcComputing Surveym, Vol. 8, No. 2, June 1976 A Sampler of Formal Definitions • 237