Showing papers by "University of New Hampshire published in 1978"

Synthesizing constraint expressions

Abstract: A constraint network representation is presented for a combinatorial search problem: finding values for a set of variables subject to a set of constraints. A theory of consistency levels in such networks is formulated, which is related to problems of backtrack tree search efficiency. An algorithm is developed that can achieve any level of consistency desired, in order to preprocess the problem for subsequent backtrack search, or to function as an alternative to backtrack search by explicitly determining all solutions.

The Nuclear and Ionic Charge Distribution Particle Experiments on the ISEE-1 and ISEE-C Spacecraft

Abstract: The ISEE-1 and ISEE-C instruments have been designed to measure the elemental abundances, charge state composition, energy spectra, and angular distributions of energetic ions in the energy range 2 keV/charge to 80 MeV/nucleon and of electrons between 75 and 1300 keV By covering the energy range between solar wind and low-energy cosmic rays the instrument will fill a gap in the knowledge especially of the nuclear and ionic composition of solar, interplanetary, and magnetospheric accelerated and trapped particles The instrument consists of three different sensor systems: ULECA is an electrostatic deflection analyzer system with rectangular solid-state detectors as energy determining devices, its energy range is ~3 to 560 keV/charge; the ULEWAT is a double dE/dX versus E thin-window flow-through proportional counter/solid-state detector telescope covering the energy range from 02 to 80 MeV/nucleon (Fe); the ULEZEQ sensor consists of a combination of an electrostatic deflection analyzer and a thin-window dE/dX versus E system with a thin-window proportional counter and a positionsensitive solid-state detector The energy range is 04 MeV/nucleon to 6 MeV/nucleon While the ULECA and the ULEWAT sensors are designed mainly for interplanetary and outer magnetospheric studies, the ULEZEQ sensor will also obtain composition data in the trapped radiation zone 65 rates and pulse-height data can be obtained with sectoring in up to 16 sectors

Geology and age of the Parguaza rapakivi granite, Venezuela

Abstract: The 1,550-my-old Paraguaza granite of the northwestern Guayana Shield in Venezuela represents one of the larger, apparently anorogenic rapakivi intrusive rocks of the world The massive rapakivi granite intrudes foliated granitic rocks and associated volcanic rocks of trans-Amazonian age in a structural setting transcurrent to the general northeast-southwest trend of the older basement rocks of the Guayana Shield Age relations and the geochemistry of the rapakivi suggest an anatectic origin from tensional effects developed by internal distortions within a continental mass The extensive 1,550-my-old Parguaza intrusion in Venezuela is correlated with 1,550-my-old basement rocks underlying the Amazon Basin in Brazil and suggests a widespread “Parguazan” event 1,500 to 1,600 my ago which affected a large part of the northwestern and southern Guayana Shield, extending as far south as the Guapore craton of Brazil The Parguazan event therefore marks an important Proterozoic episode in the tectonic evolution of the widespread Precambrian Shield area of northern South America

Winter Circulation in the Western Gulf of Maine: Part 1. Cooling and Water Mass Formation

Abstract: The mean circulation on the northeast continental shelf in the region of the Gulf of Mexico is discussed in terms of a simple box model, based on volume transports and mean salinities estimated from existing data. The results of this calculation indicate that warm salty water from the continental slope must mix with colder, fresher water at intermediate depths within the Gulf. Field measurements obtained as part of a study of the winter circulation in an offshore region in the western Gulf of Maine suggest that winter storms may be responsible for most of this vertical mixing. Ten 1-day hydrographic cruises wore conducted between the passage of seasonal storms from November 1974 to January 1975. A description of the early winter evolution of the density field was thus obtained concurrently with moored measurements of current, temperature and bottom pressure, and coastal measurements of sea level and atmospheric variables. The principal vertical mixing process observed during this period was an in...

The quantitative measure of pattern representation in images using orientation-specific color aftereffects

Abstract: A quantitative method is developed for assessing the quality of pattern information in imagery, using the magnitude of color aftereffects as an objective index. Subjects were given instructions to project imagined bar patterns of particular width and orientation onto adapting color fields, in such a manner as to simulate standard conditions for establishing the McCollough effect. Our control procedures indicate that the resulting orientation-specific complementary color aftereffects cannot be attributed to the conditioning of particular directions of eye scanning movements to color processing during adaptation, or to other possible sources of experimental bias. Furthermore, subjects who rated themselves prior to the adaptation procedure as having relatively vivid imagery showed significantly larger aftereffects than those who reported having relatively low imagery. These results not only provide an important confirmation of our earlier finding that imagination can replace physical pattern information in the formation of basic color-feature associations in the human visual system, but also demonstrate that these aftereffects can provide a practical measure of the fidelity of pattern representation in visual images.

The Magnetic Behavior of Mud Bacteria

Abstract: When separated from the substrate, Blakemore’s mud bacteria swim back to the bottom of the sea following the earth’s magnetic field lines. Their magnetotactic response appears to be due to the presence of internal ferromagnetic dipole moments of single-domain properties.

Synthesis of Flow-Duration Curves for Unregulated Streams in New Hampshire

Abstract: Flow-duration curves are concise pictures of flow variability at a point on a stream, and provide essential information for all water-resource planning. In New Hampshire, useful estimates of flow-duration curves for ungaged points on unregulated streams can be made using only information readily available from contour maps: 1) area of the basin above the point of interest; and 2) either the measured mean basin elevation or the elevations of the highest and lowest points in the basin. Measured or estimated mean basin elevation is then used in regression equations to estimate mean flow QC and the flow exceeded 95% of the time, Q95. QC is assumed to occur at the 27% exceedance frequency. Q02, Q05, and Q30 are estimated as multiples of QC. Equations are provided for calculating 95% confidence intervals for future estimates using the method. The dependence of mean flow on elevation is due to positive vertical precipitation gradients and negative vertical evapotranspiration gradients. The dependence of Q95 on elevation appears to be due largely to the fact that it rains more often, that snowmelt takes longer, and that evapotranspiration is reduced at higher elevations.

Thermodynamics of the Yang-Mills gas

Abstract: The contribution of nonlinear fluctuations (instantons) to the thermodynamics of the Yang-Mills gas at high temperature is estimated.

Silicate in anoxic pore waters and oxidation effects during sampling

Abstract: SILICA concentrations in pore fluids of sediments, and the exchange between pore water and the overlying water are important considerations for the silica budgets of the marine environment1–3. Recent studies have shown, however, that inadequate sampling and handling procedures of marine sediments can produce large compositional changes in the pore fluids of these sediments4–6. Changes in sediment temperatures, similar to those occurring during sample acquisition, can alter the pore water silica concentration by as much as 50% (ref. 7). Oxidation may also produce artefacts in pore water data, that is oxidation of iron-rich anoxic pore waters has been shown to decrease the concentration of iron and phosphate in estuarine pore waters8,9. We present here laboratory data which indicate that the exposure of anoxic pore waters to the ordinary atmosphere can reduce the silica concentration by approximately 15%, which may reduce the reported diffusional fluxes of silica from anoxic marine sediment by 15%.

Psychological, Cultural and Family Factors in Incest and Family Sexual Abuse.

Abstract: This paper reviews clinical experience and research evidence about father-daughter incest and family sexual abuse and suggests six factors important in its etiology: 1) the personal characteristics of the offender, 2) the role of the mother, 3) a milieu of abandonment, 4) subcultural isolation, 5) poor family sexual boundaries, and 6) opportunity factors.

Performance of earth dams during earthquakes

Abstract: Particular emphasis is given to dam performance in six major earthquakes—San Francisco (1906); Ojika, Japan (1939); Fallon, Nevada (1954); Kern County, California (1952); Tokachi-Oki, Japan (1967); and San Fernando, California (1971). An attempt is made to determine relationships between embankment characteristics and observed performance. It is concluded that (1)Hydraulic fill dams on stable foundations can safely withstand accelerations up to about 0.2g from Magnitude 6.5 earthquakes; (2)virtually any well-built dam can withstand moderately strong shaking up to about 0.2g or more with no detrimental effects; (3)dams built of clay soils seem to be able to withstand extremely strong shaking from large magnitude earthquakes without significant damage; (4)dams may fail up to 24 hrs after being shaken by an earthquake probably due to cracking leading to piping and erosion; and (5)primary concern should be given to dams constructed of saturated sandy soils or on sand foundation materials. Prototype performance is cited as a basis for these conclusions.

A megagametophyte analysis of genetic linkage in pitch pine (Pinus rigida mill.)

Abstract: The haploid state of conifer megagametophyte tissue provides a means of testing for genetic linkage among allozyme loci in conifers. Using pitch pine trees (Pinus rigida Mill.), which were previously determined to be heterozygous for certain allozymes, we have been able to detect linkage among several pairs of loci. One such pair, GOT-1 and GPI-2, is tightly linked showing a recombination frequency of 4 per cent. Four other pairs appear to be linked with recombination frequencies at the margin of detectability, 38–40 per cent, but tree-to-tree variation makes positive determination difficult for less tightly linked loci. Such variation may be due to small sample sizes and presence of inversion polymorphisms. These results are the first report of tight linkage in a forest tree and represent a start in mapping the conifer genome.

The philosophical development of the conception of psychology in Germany, 1780–1850.

Abstract: Although it is generally acknowledged that the modern science of psychology was produced in the mid-nineteenth century by the cross-fertilization of philosophy and physiology, few historians have tried to specify the exact role of philosophers in the evolution of modern psychology. The purpose of this article is to identify one important line of development from within early-nineteenth-century German philosophy toward the conception of psychology as an independent, experimental, and mathematical science. The thesis it proposes is that Immanuel Kant's criticism of the psychological tradition and his articulation of a specific philosophy of science provided the negative and positive foundations upon which Jakob Friedrich Fries, Johann Friedrich Herbart, and Friedrich Eduard Beneke developed the conceptualization of scientific psychology.

Biosystematic studies of the red algal genus Eucheuma. I. Electrophoretic variation among Florida populations

Abstract: Electrophoretic techniques were used to assess the degree of genetic differentiation among 4 species of the seaweed Eucheuma; E. isiforme, E. nudum, E. gelidium and E. acanthocladum. Nine Floridian populations were surveyed for 5 enzymes (14 loci), and compared using both phenotypic identity (I p )and Nei's genetic identity (I) statistics. Results suggest there is a very high degree of genetic similarity between E. isiforme and E. nudum (Ī=0.904), and between E. gelidium and E. acanthocladum (Ī=0.857), but a very low degree of similarity between these two pairs of species (Ī=0.372). These findings are in agreement with an earlier report which recommended the removal of E. gelidium and E. acanthocladum from the genus based on differences in reproductive anatomy. Greater genetic similarity was observed among the E. isiforme populations than among the E. nudum populations, the latter being ecologically more diverse and geographically or hydrographically more isolated. The proportion of polymorphic loci per population ranged from 0.25 to 0.36. Heterozygote deficiencies were observed at two acid phosphatase loci in offshore populations of E. nudum which showed a propensity for vegetative reproduction.

Adolescent life changes and illness: A comparison of three models.

Abstract: This article examines how stressful life-events relate to the occurrence of illness in a nonclinical random sample of adolescents and what processes intervene in this relationship. Three alternative models of the life events and illness relationship are compared. Data support a “direct stress and illness model” as opposed to either a “sick role behavior model” or a “mental health model.” Social support from parents appears to mediate the life events-illness relationship. Undesirable and ambiguous life events have more impact on illness than desirable events do. Results are discussed in terms of adolescence as a unique developmental stage.

Conditioned reinforcement and choice.

Abstract: In a series of three experiments, rats were exposed to successive schedule components arranged on two levers, in which lever pressing produced a light, and nose-key pressing produced water in 50% of the light periods. When one auditory signal was presented only during those light periods correlated with water on one lever, and a different signal was presented only during those light periods correlated with nonreinforcement on the other lever, the former lever was preferred in choice trials, and higher rates of responding were maintained on the former lever in nonchoice (forced) trials. Thus, the rats preferred a schedule component that included a conditioned reinforcer over one that did not, with the schedules of primary reinforcement and the information value of the signals equated. Preferences were maintained when one or the other of the auditory signals was deleted, but were not established in naive subjects when training began with either the positive or negative signal only. Discriminative control of nose-key pressing by the auditory signals was highly variable across subjects and was not correlated with choice.

Reinvestigation of the toxins from the blue‐green alga, Aphanizomenon flos‐aquae, by a high performance chromatographic method

Abstract: Toxic red tides due to blue green alga‐Aphanizomenon flos‐aquae are becomming common occurrence in the lakes of New Hampshire. The toxins from Aphaizomenon flos‐aquae were purified by a high performance chromatographic method. One of the toxins was identified as saxitoxin; the other three gave reactions indicating their structural similarity to toxins isolated from Gonyaulax tamarensis.

Contribution of receptacles from the fucoidAscophyllum nodosum to the detrital pool of a north temperate estuary

Abstract: The fucoid brown algaAscophyllum nodosum (L.) Le Jolis annually produces lateral reproductive branches (i.e. receptacles) approximately equal in weight to its vegetative thalli. The receptacles are shed within a single month during the spring. The estimated total input of receptacles to the detrital pool within the Great Bay Estuary System of New Hampshire-Maine, U.S.A., is 445 g dry wt·m−2·yr−1. Decomposition rates were rapid with only 50% or less of the original litter remaining after 50 days. Nitrogen and phosphorus flux from the litter bags varied with environmental conditions and habitats.

Relationship between Chloroplast Membrane Fatty Acid Composition and Photosynthetic Response to a Chilling Temperature in Four Alfalfa Cultivars.

Abstract: The photosynthetic responses of four alfalfa ( Medicago sativa L.) cultivars to 10 and 22 C air temperatures were examined and the relationship between the photosynthetic response at 10 C and the fatty acid composition of the chloroplast membranes was determined. Chilling-resistant cultivars exhibited moderate reductions in photosynthesis at 10 C, compared to 22 C, and contained a significantly greater percentage of polyunsaturated fatty acids in the chloroplast membrane and a greater double bond index than the chilling-sensitive cultivars. The chilling-sensitive cultivars exhibited severe reductions in photosynthesis at 10 C, compared to 22 C. The reduction in photosynthesis at 10 C is shown to be negatively correlated (r = −0.94) with the double bond index of the chloroplast membranes of the cultivars observed. The results support the hypothesis that reduced photosynthesis due to chilling temperatures is influenced by the unsaturated fatty acid composition of the chloroplast membrane which affect temperature-induced phase changes in chloroplast membrane lipids.

Graphics Programming Using the Core System

Abstract: This paper introduces the reader to the principal concepts of interactive graphics programming. These concepts are explained with examples using the Core Graphics System developed by the ACM-SIGGRAPH Graphics Standards Planning Committee (GSPC) [GSPC77]. The Core System is similar in concept to many existing packages. It is designed as a general purpose subroutine package that provides an interface between an application program and graphics hardware, such as line drawing plotters and interactive displays. The major goal of the Core System is to define this interface to be independent of the specific hardware available, so that the application can be used on different computer configurations with minimal changes to the application program. The Core System provides basic application-independent facilities for creating arbitrary views of twoand three-dimensional objects and for supporting interaction between the application program and its user. Higher level utility subroutine packages, using the Core System functions, might be developed to serve the needs of specific application areas, such as computer-aided design or cartography. Other papers in this issue of COMPUTING SURVEYS describe the history and methodology that underlie the Core System [NEWM78], provide an overview of its features

Broad-spectrum bacterial agglutinating activity in the serum of the horseshoe crab, Limulus polyphemus

Abstract: Serum obtained from the horseshoe crab agglutinated a wide variety of heat-killed bacteria. Gram-positive species reactive with this serum included various cocci and the bacillus Listeria monocytogenes . Among the Gram-negative bacilli examined, both members of the family Enterobacteriaceae as well as others were agglutinated. Agglutinin-adsorption studies supported the hypothesis that the agglutinin reactive with Salmonella minnesota is distinct from that binding to Gram-positive bacteria. Adsorption by each of six R mutants reduced the serum's ability to agglutinate the corresponding wild-type strain of S. minnesota . Pretreatment of serum with either chloroform or ethyl ether had no demonstrable effect on the agglutinating activity. Comparative studies of serum versus plasma indicated that the material responsible for this activity is present naturally in the fluid portion of the hemolymph. The substance in L. polyphemus serum responsible for agglutinating bacteria is probably equivalent to the recognized hemagglutinin but distinct from that responsible for the endotoxin-mediated clotting reaction.

Fate of Nutrients During Aerobic Digestion

Abstract: Laboratory scale aerobic digestion experiments were performed and nutrient balances were maintained in order to evaluate nutrient transformations during digestion of waste activated sludge. Reactors loaded at 0.03 ft³ and 0.081 lb VS/day/ft³, were operated under both batch and daily feed conditions. Significant nitrification occurred, resulting in substantial reductions in pH and alkalinity. Denitrification occurred when dissolved oxygen concentrations dropped below 1.0 mg/l. Phosphorus and nitrogen were released to the liquid in approximately a stoichiometric ratio to the volatile solids destroyed. As much as 37% of the phosphorus and 41% of the nitrogen in the feed sludge was found in the supernatant after digestion. The solid phase of aerobically digested waste activated sludge had a nitrogen content of 7% of the suspended solids and a phosphorus content of 2% of the suspended solids.

Seasonal burrowing behavior and ecology of aporrhais occidentalis (gastropoda : strombacea)

Abstract: 1. SCUBA observations and in situ tagging experiments were carried out on a population of Aporrhais occidentalis during 1973-1976. Seasonal changes in burrowing behavior were quantified by determining the percentage of tagged snails found burrowing each month. Gut content analyses were performed at monthly intervals to determine if the intensity of feeding activity fluctuates seasonally. Empty A. occidentalis shells were collected and examined for evidence of predation. 2. Specimens of A. occidentalis alternate between periods of epifaunal activity and infaunal quiescence. Tagged snails tended to remain burrowed from August through January, but were active on the surface of the substrate from February until late summer. Gut content analyses showed that the snails fed actively during their epifaunal period, but ceased feeding while burrowed. 3. Laboratory attempts to influence burrowing behavior by manipulating water temperature were unsuccessful. 4. Published observations on eastern Atlantic species of Aporrhais suggest that seasonal burrowing behavior may be characteristic of the genus.