Showing papers by "Texas A&M University published in 1982"
TL;DR: The overall findings indicate that treatment in methadone maintenance, therapeutic communities, and outpatient drug-free programs was effective in improving posttreatment performance with respect to drug use, criminality, and productive activities.
Abstract: The results of the treatment evaluation research based on the Drug Abuse Reporting Program (DARP) are summarized and discussed. The DARP is a data system containing almost 44,000 admissions during 1969 to 1973 to 52 treatment programs located throughout the United States and in Puerto Rico. The current report focuses on the findings of a number of interlocking posttreatment follow-up studies based on data for three independent samples representing admissions to this system. These data include a total of 4,627 interviews conducted 5 to 7 years after admission to the DARP, and an average of over 4 years after termination from treatment. The overall findings indicate that treatment in methadone maintenance, therapeutic communities, and outpatient drug-free programs was effective in improving posttreatment performance with respect to drug use, criminality, and productive activities. Significantly poorer outcomes were reported for outpatient detoxification programs and a group of comparison (intake only) clients.
492 citations
TL;DR: It is shown that the proposed hybrid ARQ scheme provides both high system throughput and high system reliability, particularly attractive for error control in high-speed data communication systems with significant roundtrip delays, such as satellite channels.
Abstract: This paper presents a new type of hybrid ARQ scheme for error control in data communication systems. The new scheme is based on the concept that the parity-check digits for error correction are sent to the receiver only when they are needed. Normally, data blocks with some parity-check bits for error detection are transmitted. When a data block D is detected in errors, the retransmissions are not simply repetitions of D , but alternate repetitions of a parity block P(D) and D . The parity block P(D) is formed based on D and a half-rate invertible code which is capable of correcting t or fewer errors and simultaneously detecting d (d > t) or fewer errors. When a parity block is received, it is used to recover the originally transmitted data block either by inversion or by decoding operation. The repetitions of the parity block P(D) and the data block D are alternately stored in the receiver buffer for error correction until D is recovered. We show that the proposed hybrid ARQ scheme provides both high system throughput and high system reliability. It is particularly attractive for error control in high-speed data communication systems with significant roundtrip delays, such as satellite channels.
419 citations
TL;DR: This article focused on three rationales for corporate philanthropy: through-the-firm giving, corporate statesmanship, and profit motivated giving, and the profit motivation argument was exa...
Abstract: Existing literature has focused on three rationales for corporate philanthropy: through-the-firm giving, corporate statesmanship, and profit motivated giving. The profit motivation argument was exa...
345 citations
TL;DR: In this article, an iterative procedure based on constrained entropy maximization is presented for reconstruction of electron density from imperfect single-crystal X-ray diffraction data, which yields true super-resolution and is economical even for protein crystal structures.
Abstract: Information theory provides a uniquely powerful apparatus for reconstructing an image from imperfect data in its dual space. An iterative procedure based on constrained entropy maximization is presented here for reconstruction of electron density from imperfect single-crystal X-ray diffraction data. In the ideal situation, continuous electron density, its periodicity given by the lattice, is the Fourier transform of an infinite set of structure factors whose squared moduli are observables. An ideal electron density is unattainable from experiment because of the common experimental inadequacies of incomplete and noisy data discussed by Gull and Daniell1. These inadequacies are partially overcome in the present procedure which yields true super-resolution and is economical even for protein crystal structures as illustrated.
325 citations
TL;DR: For instance, this paper found that subjects who were placed in a hunched, threatened physical posture verbally reported self-perceptions of greater stress than subjects who had been placed in an expansive, upright posture.
Abstract: Four studies were conducted in a laboratory setting to examine whether variations in physical posture can have a regulatory or feedback role affecting motivation and emotion. The results of the first study, which were replicated in the second study, revealed that subjects who had been temporarily placed in a slumped, depressed physical posture later appeared to develop helplessness more readily, as assessed by their lack of persistence in a standard learned helplessness task, than did subjects who had been placed in an expansive, upright posture; surprisingly, there were no differences in verbal reports. The third study established that physical posture was an important cue in observers' verbal reports of depression in another person. The fourth study further explored the role of posture in self-reports of emotion using another posture. The results indicated that subjects who were placed in a hunched, threatened physical posture verbally reported self-perceptions of greater stress than subjects who were placed in a relaxed position. The findings of these studies are interpreted in terms of self-perception theory. It is suggested that physical postures of the body are one of several types of cues that can affect emotional experience and behavior.
287 citations
TL;DR: In this article, the authors develop and explore a theory dealing with an important facet of agricultural runoff problems, which is a nonpoint externality with notable implications for both research and policy.
Abstract: The purpose of this paper is to develop and explore a theory dealing with an important facet of agricultural runoff problems. Agricultural runoff is a nonpoint externality with notable implications for both research and policy. A nonpoint externality exists whenever the externality contributions of individual economic agents cannot be practically measured by direct monitoring. Without monitoring, regulations on emissions cannot be enforced, and charges or subsidies cannot be assessed. Thus, policies which are usually suggested for pollution abatement are not available. There is great need for a theoretical base that can adequately capture these facts. Such a theory yields some important implications even before specific empirical applications. The economic problem of agricultural runoff can be separated into three distinct categories. First, the sediment, nutrients, and chemicals removed by runoff represent a loss of resources to the individual farmer. These costs are borne privately by farmers. Second, if the discount rate of the individual farmer is greater than the social discount rate, or if the farmer has a planning horizon which is shorter than society's, the farmer will mine the soil resource at a rate which is more depletive than is socially optimal. This is a temporal externality. A third category involves the conservation of mass. Physical resources lost by the individual farm must appear elsewhere in the environment. In sufficient quantities, these resources are pollutants. Since water is the primary transport media for these resources, it is water that is polluted by soil, nutrients, and agricultural chemicals. This spatial externality has been the focus of much research. Here we intend to develop a theory for these issues, to employ it to suggest a revised research methodology, and to provide some important conclusions about alternative runoff policies. Only two of the three categories of agricultural runoff problems involve externalities, and only the spatial externality is considered here.
260 citations
TL;DR: Assessment of the binding affinities of 16 highly-purified, synthetic chlorinated biphenyl (PCB) congeners for the Ah receptor suggests that chemicals other than "pure MC-type' inducers can bind to the cytosolic receptor.
259 citations
TL;DR: With age, a distinct pericellular matrix or “nest,” consisting of collagen fibrils, fine filaments, dense particles, and banded structures, formed around most cells with no apparent preference for viable or necrotic cells, suggesting accumulation of cell products.
Abstract: The cells of the intervertebral disc exist in a unique environment; not only are discs subject to large mechanical loads, they are the largest avascular structures in the body. To describe the ultrastructure and age changes in cells from human nucleus pulposus, we studied these cells in individuals ranging in age from the 26th week of fetal life to 91 years. Viable chondrocyte-like cells existed in specimens from all ages. The presence of Golgi cisternae and well-developed endoplasmic reticulum in these cells suggests that they are capable of producing and maintaining the extracellular matrix. Necrotic cells were also present in all samples, and many cells which appeared viable when examined by light microscopy proved to be necrotic when examined by electron microscopy. The percentage of necrotic cells increased with age from 2% or less in fetal specimens to over 50% in adults. In addition, with age, a distinct pericellular matrix or "nest," consisting of collagen fibrils, fine filaments, dense particles, and banded structures, formed around most cells with no apparent preference for viable or necrotic cells. Nest formation and increasing density of the cell nests may reflect accumulation of cell products.
255 citations
TL;DR: The structure of notochordal cells and their persistence in the nucleus pulposus after fetal life suggest that they may have a significant role in the formation and maintenance of the nucleus Pulposus.
Abstract: We examined nucleus pulposus notochordal cells of individuals ranging in age from the eighth week of fetal life to 32 years of age. With increasing age, notochordal cell structure changed, as did the cell-to-cell relationships and the cell-to-chordal relationships. All notochordal cells contained normal organelles, including well-developed endoplasmic reticulum, but, in addition, fetal notochordal cells demonstrated an unusual relationship between rough endoplasmic reticulum and mitochondria: elements of the rough endoplasmic reticulum encircled almost every mitochondrion. Fetal notochordal cells contained large amounts of glycogen, while older cells had much smaller glycogen deposits. Cytoplasmic filaments were observed in cells of all ages. The cells formed tightly packed clusters in the fetus with little, if any, extracellular matrix between individual cells. Cells separated from each other with age and by the twenty-first week of fetal life, only slender strands of cytoplasm connected them. Previous light microscopic studies described notochordal cells as 'physaliphorus' cells since they appeared to contain large cytoplasmic vacuoles. However, electron microscopy showed that these apparent vacuoles consist of extracellular matrix surrounded by cells or cell processes. The structure of notochordal cells and their persistence in the nucleus pulposus after fetal life suggest that they may have a significant role in the formation and maintenance of the nucleus pulposus.
255 citations
TL;DR: In this paper, role set configuration is examined as a predictor of ethical/unethical behavior among two random samples of advertisers [corporate clients and ad agency account executives] and the specific reported behaviors analyzed are intraorganizational behaviors available to most employees.
Abstract: Role-set configuration is examined as a predictor of ethical/unethical behavior among two random samples of advertisers [corporate clients and ad agency account executives]. The specific reported behaviors analyzed are intraorganizational behaviors available to most employees. The conceptual framework is based on differential association theory and role set configuration analysis. The three dimensions of role-set configuration used to predict ethical/unethical behavior are organizational location, relative authority and referent others' beliefs and behaviors as perceived by the focal person. The focal person's opportunity to participate in unethical behavior is also a predictor variable. Eighty-nine corporate clients and 136 agency advertisers responded to a questionnaire [a 33% return rate] consisting of a slightly revised version of Newstrom and Ruch's ethics scale. Seven types of predictors of ethical/unethical behavior, "What I do," are developed through principal component factor analysis. These seve...
243 citations
TL;DR: Empirical technology-structure research from 1965 through 1980 is summarized and with some exceptions, strong support was found for the existence of technology-Structure relationships.
Abstract: Empirical technology-structure research from 1965 through 1980 is summarized. An examination is made of the influence on research caused by the use of different (1) conceptualizations of technology and structure, (2) levels of analysis, and (3) types of measures. With some exceptions, strong support was found for the existence of technology-structure relationships.
TL;DR: The results indicated that the most important variables affecting decision support system usage were accuracy ofoutput, user training, relevancy of output, and the decision maker's experience.
Abstract: This study investigates factors that may affect the use of decision support systems The independent variables investigated included: characteristics of the decision makers such as age, educational level, experience, and cognitive style; characteristics of the decision support system such as response time, accuracy, timeliness, relevancy of output, format, and the distance traveled to interact with the system; and characteristics of the implementation process such as user involvement, user training, and top management support The study included 8 systems and 64 subjects from the oil industry The results indicated that the most important variables affecting decision support system usage were accuracy of output, user training, relevancy of output, and the decision maker's experience
Subject Areas: Decision Support Systems, Information Management, and Organizational Behavior
TL;DR: In this article, the authors describe the anticyclonic rings that separated from the Loop Current in the eastern Gulf of Mexico and used the historical data set to determine that these rings typically translate to the west at a mean speed of 2.1 km day−1.
Abstract: Using the historical data set, this study describes the anticyclonic rings that separated from the Loop Current in the eastern Gulf of Mexico. Six quasi-synoptic data sets are used to describe the evolving circulation of the Gulf of Mexico from October 1966 to September 1967, showing the separation and movement into the western Gulf of three anticyclonic rings. The historical data are used to determine that these rings typically translate to the west at a mean speed of 2.1 km day−1. Their length scale as defined by their rms radii is 183 km. An estimate of ring life-span, as defined by an e-folding time, is one year. Within the context of the Gulf's water property distributions, these rings appear as warm salty bodies. The heat and salt added by one of these rings after separation are estimated to be 7×109 J m−2 and 17 g cm−2, respectively. The heat and salt added by one of these features play an important role in the heat and salt budget of the western Gulf. The latter indicates that about one r...
TL;DR: In this article, it was shown that the pole assignment problem can be reduced to solving the linear matrix equations AX − XA = −BG, FX = G successively for X, and then F for almost any choice of G.
01 Jul 1982
TL;DR: The nitrogenous nutrition of the phytoplankton in the Scotia Sea was investigated with 15 N tracer techniques during the austral summer of 1979 as discussed by the authors, and the results showed that phyto-ankton showed a consistent preference for NH 4 + utilization relative to NO 3 −.
Abstract: The nitrogenous nutrition of the phytoplankton in the Scotia Sea was investigated with 15 N tracer techniques during the austral summer of 1979. On a regional scale, ambient NH 4 + concentrations in the upper hundred meters were variable (0.1 to 2.5 μg-at. 1 −1 ) and one or more orders of magnitude lower than ambient NO 3 − concentrations (17 to 31 μg-at. 1 −1 ). Despite the abundance of NO 3 − , late summer phytoplankton showed a consistent preference for NH 4 + utilization relative to NO 3 − . This was determined by use of a relative preference index and the patterns are similar to those of other marine, estuarine, and fresh waters to which it has been applied. The ratio of NO 3 − utilization to total nitrogen utilization indicated that when ambient NH 4 + concentrations were > 1.0 μg-at. 1 −1 , NO 3 − accounted for s40% of the total nitrogen utilized. Thus, even when NO 3 − is present in quantities that approach the upper limits for near-surface open-ocean waters, the processes that recycle NH 4 + locally can make a major contribution to the nutrition of the phytoplankton. Data for NO 3 − uptake from the 0.1% light level at several of the southernmost stations appeared anomalous. The observed values were higher than would have been expected solely from phytoplakton uptake.
TL;DR: In this article, a detailed analysis of the psychometric nature of racial and social class differences on the original 13 subscales of the Wechsler Intelligence Scale for Children-Revised (WISC-R) was performed, and the profiles of subtest scores of whites and blacks were compared directly and also after the racial groups were statistically equated on Full Scale IQ (FSIQ).
TL;DR: In this paper, Measuring Environmental Concern: The New Environmental Paradigm Scale is proposed as a scale for measuring environmental concern. The Journal of Environmental Education: Vol. 13, No. 3, pp. 39-43.
Abstract: (1982). Measuring Environmental Concern: The New Environmental Paradigm Scale. The Journal of Environmental Education: Vol. 13, No. 3, pp. 39-43.
TL;DR: In this article, the authors examine the validity of these assumptions and their implications for assessing organization performance and propose a method to evaluate the linkages among characteristics of organizations. But their method assumes that organizations exhibit a oneness of structure and that linkages between characteristics of organisations are rational.
Abstract: Current perspectives on the assessment of organization performance assume that organizations exhibit a oneness of structure and that the linkages among characteristics of organizations are rational. This paper examines the validity of these assumptions and their implications for assessing organization performance.
TL;DR: The relative activities of the PCB congeners as inducers of cytochrome P-448-dependent monooxygenase in vitro were similar to their potencies as microsomal enzyme inducers in the immature male rat.
TL;DR: In this paper, performance appraisals of nonmanagement employees of a large supply organization were analyzed for effects of employee and supervisor race and sex, and the effects of these effects accounted for less than 1% of the total race-and sex effects.
Abstract: Performance appraisals of nonmanagement employees of a large supply organization were analyzed for effects of employee and supervisor race and sex. Total race and sex effects accounted for less tha...
TL;DR: In this article, the authors test the three leading explanations for the correlation between government deficits and inflation and find no support for either of the first two hypotheses, nor for the third hypothesis, and conclude that expected government deficits have no significance for future inflation.
Abstract: There is a pronounced positive correlation of inflation andgovernment deficits in the United States since World War II.The purpose of this paper is to test the three leading explanationsof this correlation. These three explanations are: (a) a deficitincreases prices through a wealth effect; (b) a deficit results inthe Federal Reserve purchasing debt, thus increasing the moneysupply and prices; and (c) expected inflation increases the deficit(which is the change in the nominal value of bonds). No supportis found for either of the first two hypotheses. The results indi-cate that expected government deficits have no significance forfuture inflation.Since World War II, the United States has experienced large federal-government deficits and a sustained peacetime inflation. Three differentconnections between the deficits and inflation are prominent in theliterature.The most direct connection between government deficits and inflationis that by increasing the real value of outstanding bonds and perceived netwealth, a deficit can raise total spending and the price level. This connec-tion is also the most long-standing and is suggested by Metzler (1951) andPatinkin (1965) for example.Monetarists generally and Buchanan and Wagner (1977) in particularhave emphasized a different link between deficits and inflation. They sug-gest that the Federal Reserve purchases government bonds when the Trea-sury sells bonds, thus increasing high-powered money, the money supply,and the price level. The Federal Reserve might behave this way, for exam-ple, because it is attempting to hold down interest rates on governmentsecurities when deficits occur.Recently, Barro (1978, 1979) has put forward a hypothesis that deficitsare a result of inflation, rather than inflation being a result of deficits. Thegovernment deficit is the change in the nominal value of outstanding gov-ernment bonds. If the anticipated inflation rate increases, then the nomi-nal value of bonds must increase, i.e., the government will run a deficit, tokeep the same anticipated real amount of bonds.All three of these possible connections between government deficitsand inflation are consistent with the observed positive correlation of defi-cits and inflation. The implications, however, are strikingly different con-
TL;DR: In this article, the authors studied the hydrogenation of carbon monoxide using a mixture of three different silicas and three different zeolites and found that the selectivity and the activity of the catalysts are strongly dependent on the nature of the support and on the state of the metal on its surface.
TL;DR: The previously advanced hypothesis that desiccation resistance involves the replacement of water adjacent to intracellular surfaces with polyhydroxy compounds has been supported by experiments on cysts of the brine shrimp, Artemia, and in a model system of albumin--glycerol--water, using nuclear magnetic resonance spectroscopy, microwave dielectrics, and density measurements.
TL;DR: In this article, the authors made estimates of the net transport through Drake Passage for three periods during which the year-long DRAKE 79 current meter array spanning the Passage was in operation.
Abstract: Estimates of the net transport through Drake Passage are made for three periods during which the year-long DRAKE 79 current meter array spanning the Passage was in operation. Relative geostrophic shears from hydrographic surveys in January 1979, April 1979 and January 1980 were referenced to directed speed measurements to give profiles of net speed. Direct measurements were averaged in time to make them more compatible with the spatially-averaged baroclinic shears. The agreement between directly-measured and baroclinic shears is generally good except in regions of large bathymetric relief and during periods when current cores were shifting past or between moorings. The presence of cold-core rings during two of the DRAKE 79 hydrogaphic surveys resulted in intensified flow and increased transport within fronts, but did not affect the net transport through the Passage. The three latest estimates of net transport (117, 144 and 134 × 106 m3 s−1) are in close agreement with a previous estimate of 124 ×...
TL;DR: In this article, a microcomputer-based prototype relay was constructed and installed on a typical utility feeder to detect most staged faults while not indicating a false trip during a three month demonstration.
Abstract: This paper describes work performed by Texas A&M University on the detection of high impedance faults on distribution primary conductors. Some grounded distribution primary conductors may exhibit a very low fault current such that they may not be cleared by over-current protection. These faults may persist indefinitely, possibly causing a fire hazard or a hazard to humans by contact with an energized line. The paper begins with an examination of the high impedance fault problem from the perspective of system protection. The fault detection theory is presented next. The system utilizes a fault-generated increase in the 2-10 kHz component of feeder current for fault detection. EPRI funding enabled the verification and demonstration of this fault detection concept. Measurements were made on several faulted and unfaulted feeders to develop a representative data base of signals to which a relay would be subject. Analysis of these data provided a time and frequency domain signature of these faults. A microcomputer-based prototype relay was constructed and installed on a typical utility feeder. It successfully detected most staged faults while not indicating a false trip during a three month demonstration.
TL;DR: In this article, data from four studies were analyzed to identify effective patterns of leadership behavior for military cadets and Air Force officers, including performance emphasis, inspiration, role clarification, and criticism.
TL;DR: The nuclear polyhedrosis virus of the alfalfa looper Autographa californica contains a double-stranded, circular DNA genome and 14 scientists agreed to accept an orientation of this circular genome with respect to a physical map of the restriction endonuclease cleavage sites.
Abstract: The nuclear polyhedrosis virus of the alfalfa looper Autographa californica contains a double-stranded, circular DNA genome. Fourteen scientists agreed to accept an orientation of this circular genome with respect to a physical map of the restriction endonuclease cleavage sites.
TL;DR: Intact teeth were obtained from three cadavers of known age 57, 67, and 76 years, respectively and cross-sections 100-150 μm thick were taken from the roots using a diamond saw to determine the estimated age for that cadaver.
Abstract: Intact teeth were obtained from three cadavers of known age 56, 67, and 76 years, respectively. Cross-sections 100-150 micrometers thick were taken from the roots using a diamond saw. Individual sections were stained, mounted on glass slides, and photographed on a light microscope. The usual number of years for the eruption of any particular tooth were added to the annulation count to determine the estimated age for that cadaver.
TL;DR: The relationship of marbling level and cooking to cholesterol content of beef longissimus muscle steaks was studied in this paper, which showed that raw steaks with "practically benign" marbling contained significantly less cholesterol (wet basis) than did raw Steaks with any of the other seven marbling scores.
Abstract: The relationships of marbling level (eight levels from “Moderately Abundant” to “Practically Devoid”) and cooking to cholesterol content of beef longissimus muscle steaks were studied. Only raw steaks with “Practically Devoid” marbling contained significantly less cholesterol (wet basis) than did raw steaks with any of the other seven marbling scores. However, steaks cooked to an internal temperature of 60° or 75°C showed no significant differences in cholesterol content among any of the eight marbling groups. The cholesterol content of cooked steaks was 22–48% higher than that of raw steaks when cooked to 60°C and 38–65% higher when cooked to 75°C; cooking reduced the weight of each steak, thereby increasing the cholesterol content of the steak expressed as a percentage of the cooked weight.