Showing papers by "University of New Hampshire published in 1986"

Toward an understanding of the burnout phenomenon.

Abstract: Les auteurs decrivent les antecedents et les consequences du phenomene de «burnout» (Freudenberger, 1974) apparaissant dans certaines professions et constitue des trois composantes d'epuisement emotionnel de depersonnallisation et de sentiments d'echec personnel

An analysis of risk markers in husband to wife violence: the current state of knowledge.

Abstract: The present review involves the evaluation of 97 potential risk markers of husband to wife violence. Using 52 case-comparison studies as the source of data, markers were divided into four categories: consistent risk, inconsistent risk, consistent nonrisk, and risk markers with insufficient data. Based on this classification, it appears that a number of widely held hypotheses about husband to wife violence have little empirical support. Only witnessing violence in the wife's family of origin was consistently associated with being victimized by violence. Furthermore, it seems that characteristics associated with either the husband-offender or the couple have greater utility for assessing the risk of husband to wife violence than characteristics of the wife-victim. Findings are discussed in terms of the methodological and theoretical implications of current research on this form of adult domestic violence.

Parafoveal word processing during eye fixations in reading: Effects of word frequency

Abstract: The present experiment measured eye fixations in reading to determine whether word frequency affects the processing of the fixated word and the processing of the word to the right of the fixated word (the parafoveal word). In the experiment, subjects read sentences that contained either a critical high- or low-frequency target word. High- and low-frequency targets were matched on word length and a number of other variables. In one condition, parafoveal visual information to the right of the fixated word was denied or distorted; in other conditions, information about the parafoveal word to the right of the fixated word was available. The main results showed shorter fixations on high-frequency than on low-frequency target words. Furthermore, readers gained more effective previews from high-frequency parafoveal target words than from low-frequency parafoveal target words.

An Autoregressive Model Approach to Two-Dimensional Shape Classification

Abstract: In this paper, a method of classifying objects is reported that is based on the use of autoregressive (AR) model parameters which represent the shapes of boundaries detected in digitized binary images of the objects. The object identification technique is insensitive to object size and orientation. Three pattern recognition algorithms that assign object names to unlabelled sets of AR model parameters were tested and the results compared. Isolated object tests were performed on five sets of shapes, including eight industrial shapes (mostly taken from the recognition literature), and recognition accuracies of 100 percent were obtained for all pattern sets at some model order in the range 1 to 10. Test results indicate the ability of the technique developed in this work to recognize partially occluded objects. Processing-speed measurements show that the method is fast in the recognition mode. The results of a number of object recognition tests are presented. The recognition technique was realized with Fortran programs, Imaging Technology, Inc. image-processing boards, and a PDP 11/60 computer. The computer algorithms are described.

Sulfate and nitrate concentrations from a south Greenland ice core

Abstract: An ice core in south Greenland covering the period 1869 to 1984 was analyzed for oxygen isotopes and chloride, nitrate, and sulfate concentrations. The data show that the "excess" (nonsea-salt) sulfate concentration has tripled since approximately 1900 to 1910 and the nitrate concentration has doubled since approximately 1955. The increases may be attributable to the deposition of these chemical specis from air masses carrying North American and Eurasian anthropogenic emissions.

Risk Factors for Child Sexual Abuse

Abstract: A number of surveys have by now provided information about the relative risk of persons from various backgrounds to experience sexual abuse during childhood. Interestingly, they are fairly uniform in failing to find differences in rates according to social class or race. However, several other factors have emerged from community studies as being consistently associated with higher risk for abuse: (a) when a child lives without one of the biological parents; (b) when the mother is unavailable to the child either as a result of employment outside the home or disability and illness; (c) when the child reports that the parents' marriage is unhappy or conflictual; (d) when the child reports having a poor relationship with the parents or being subject to extremely punitive discipline or child abuse; (e) when the child reports having a stepfather. The article draws some implications from these findings and makes recommendations for ways to improve subsequent studies of risk factors.

Phytoplankton production in the Delaware Estuary: temporal and spatial variability

Abstract: Phytoplankton production in the Delaware Estuary (USA) was measured over several seasonal cycles (1980-1985). Seasonal variability in daily area1 production (JP; g C m-2 dl ) was dlrectly related to chlorophyll concentrations in the upper estuary, ranging from a maximum of 1.1 g C m-' d ' In summer to a minlmum of d-l) dunng summer in the presence of low phytoplankton biomass (2 to 10 kg Chl I ' ) , and in mid-estuary [2.6 g C d-l) during the spring diatom bloom (50 to 60 yg Chll-l). Desplte the occurrence of maximum nutnent concentrations in the freshwater region, highest JP and 90 % of the annual production occurred in the lower estuary, down-stream from the turbidity maximum. The presence of the turbidity maximum immediately downstream from major anthropogenic nutrient sources restricts phytoplankton growth, and limits biomass accumulation below nuisance levels. Annual production for the 1981-1985 period averaged 307 g C and displayed marked inter-annual variability. Llght availability is the predominant regulator of production in the estuary. Although growth was light-limited, neither chlorophyll specific produchon nor the light intensity at which photosynthesis saturates was related to the mean light intensity in the mixed surface-layer. These results suggest that photoadaptive response times are slower than the vertical mlxing rate and that photoadaptation is of mlnor significance to overall production in the system.

Explanations of pedophilia: A four factor model

Abstract: We review a variety of theories that have been proposed to explain why adults become sexually interested in and involved with children All the theories appear to be directed to explaining one of four factors: (a) emotional congruence—why the adult has an emotional need to relate to a child; (b) sexual arousal—why the adult could become sexually aroused by a child; (c) blockage—why alternative sources of sexual and emotional gratification are not available; or (d) disinhibition—why the adult is not deterred from such an interest by normal prohibitions We illustrate how these four factors can be combined to explain more of the diversity in pedophilic behavior than is usually explained by single factor theories We also introduce the idea of viewing types of pedophilia on a continuum rather than in the traditional way of treating them as dichotomies

Sorption of trace metals by humic materials in soils and natural waters

Abstract: Trace metal sorption by coagulated humic acid and peat materials can be described macroscopically either as a complexation or a cation exchange phenomenon. Model equilibrium constants or selectivity coefficients for trace metal sorption by H‐form humic materials are special cases of two general models which do not depend on the sorption mechanism. Sorption mechanisms can be elucidated by spectroscopic techniques, both optical and magnetic resonance, but no information about mechanisms can be inferred from equilbrium constants.

Degree and Range of Recreation Specialization: Toward a Typology of Boating Related Activities

Abstract: This paper extends previous specialization research by using the concept to compare individuals who participate in different boating activities and sub-activities. Analyses were based on a statewid...

Age and composition of the grão pará group volcanics, serra dos carajás

Abstract: Metavolcanic rocks underlying the Serra dos Carajas iron ore deposits yield Late Archean ages, and show isotopic and chemical evidence of assimilation of some of the continental crust through which they erupted. The lower metavolcanic sequence of the Grao Para Group North and East of the Serra Norte iron deposits is bimodal, with dominant basalts, basaltic andesites, and trachyandesites, and subordinate rhyolite tuffs and flows at several stratigraphic levels. Most volcanic rocks are of medium to low metamorphic grade, with more intense metamorphism and deformation along the northern contact with gneisses and granitoid rocks (Xingu Complex). Thickness of the volcanic section is not known, but may bc about 4·6 km. The basalts and basaltic andesites yleld a whole rock Rb-Sr isochron age of 2,687 ± 54 Ma. The initial Sr isotopic ratio of 0.7057 ± 0.0010 demonstrates that the basalts incorporated material that had history of elevated Rb/Sr ratios. Sm-Nd ratios in the mafic rocks are too tightly clustered to yield an isochron, and using the zircon age of 2,758 Ma they yield €Nd values varying from +4.6 to -7.0, averaging +0.6. The Nd and Sr isotopic data and the trace and rare-earth element compositions of these mafic rocks are ali consistent with contamination of mantle-derived melts by significant but variable amounts of diverse older continental crust. The stratigraphy, geochemical and isotopic compositions show that the group originated on extending, older continental crust. An age-terrane boundary must exist between this Arehean continental terrane and the apparently ensimatic Early Proterozoic greenstone belta of the northern Amazonian craton.

Effects of dehydroepiandrosterone acetate on metabolism, body weight and composition of male and female rats.

Abstract: Twenty adult Sprague-Dawley outbred rats (10 male and 10 female) were fed a nonpurified diet without or containing dehydroepiandrosterone acetate (DHEA 6 g/kg diet) for 11 w. DHEA-treated animals weighed less than the controls after 6 wk and until the end of treatment. However, only the differences between male groups were statistically significant. Food intake of the DHEA-fed animals was not affected, but resting heat production was elevated for both sexes. Serum triglyceride levels and activity of hepatic glucose-6-phosphate dehydrogenase of the experimental groups were lower than controls. Analyses of body composition indicated DHEA-treated animals had proportionately less body fat and therefore more body water, protein and ash than controls. In most cases, differences in body composition were due primarily to effects of DHEA on the female animals. In a second experiment, DHEA treatment did not alter urinary ketone levels nor did it enhance citrate synthase activity in interscapular brown fat, skeletal muscle, heart or liver. Findings suggest that DHEA acetate treatment affected body weight, body composition and utilization of dietary energy by both impairing fat synthesis and promoting fat-free tissue deposition and resting heat production. Possible mechanisms by which DHEA may affect metabolism are discussed.

Estimation of p(y<x) in the gamma case

Abstract: We consider estimation of P(Y

Beyond bathymetry: Mapping acoustic backscattering from the deep seafloor with Sea Beam

Abstract: In its standard mode of operation, the multibeam echo sounder Sea Beam produces high resolution bathymetric contour charts of the seafloor surveyed. However, additional information about the nature of the seafloor can be extracted from the structure of the echo signals received by the system. Such signals have been recorded digitally over a variety of seafloor environments for which independent observations from bottom photographs or sidescan sonars were available. An attempt is made to relate the statistical properties of the bottom‐backscattered sound field to the independently observed geological characteristics of the seafloor surveyed. Acoustic boundary mapping over flat areas is achieved by following trend changes in the acoustic data both along and across track. Such changes in the acoustics are found to correlate with changes in bottom type or roughness structure. The overall energy level of a partial angular‐dependence function of backscattering appears to depend strongly on bottom type, whereas ...

Maternal regulation of fecundity: non-random ovule abortion inCassia fasciculata Michx.

Abstract: We examined the extent of ovule abortion and the within-fruit pattern of abortion inCassia fasciculata, an annual legume, and tested the hypothesis that abortion can result from competition for limited maternal resources among developing fruits and seeds. In a natural population at Mayview, IL, 53.4% of ovules in mature fruits matured as seeds; 43.4% showed some development but aborted, and 3.1% showed no development over virgin ovules. In a greenhouse experiment in which treatments were applied after most fruits were initiated, nutrient addition and partial root removel had no effect on abortion, but drought reduced the proportion of ovules maturing to 75% of the control mean. A fruit thinning experiment was conducted in which the number of fruits initiated on certain plants was limited. Control plants had more ovule abortion than fruit-thinned plants, suggesting that abortion resulted from competition for limited maternal resources. A "position effect" was observed in both field and greenhouse populations; ovules toward the fruit base (pedicellar end) had higher frequencies of abortion than those at the distal end. Thus, ovule abortion, like fruit abortion in this species, is non-random. Indivisuals regulate fecundity at both the whole fruit and individual seed levels.

Bathymetric Artifacts in Sea Beam Data: How to Recognize Them and What Causes Them

Abstract: Sea Beam multibeam bathymetric data have greatly advanced understanding of the deep seafloor. However, several types of bathymetric artifacts have been identified in Sea Beam's contoured output. Surveys with many overlapping swaths and digital recording on magnetic tape of Sea Beam's 16 acoustic returns made it possible to evaluate actual system performance. The artifacts are not due to the contouring algorithm used. Rather, they result from errors in echo detection and processing. These errors are due to internal factors such as side lobe interference, bottom-tracking gate malfunctions, or external interference from other sound sources (e.g., 3.5 kHz echo sounders or seismic sound sources). Although many artifacts are obviously spurious and would be disregarded, some (particularly the “omega” effects described in this paper) are more subtle and could mislead the unwary observer. Artifacts observed could be mistaken for volcanic constructs, abyssal hill trends, hydrothermal mounds, slump blocks, or channels and could seriously affect volcanic, tectonic, or sedimentological interpretations. Misinterpretation of these artifacts may result in positioning errors when seafloor bathymetry is used to navigate the ship. Considering these possible geological misinterpretations, a clear understanding of the Sea Beam system's capabilities and limitations is deemed essential.

Microbial iron reduction by enrichment cultures isolated from estuarine sediments.

Abstract: Microbial Fe reduction in acetate- and succinate-containing enrichment cultures initiated with an estuarine sediment inoculum was studied. Fe reduction was unaffected when SO42− reduction was inhibited by MoO42−, indicating that both processes could occur independently. Bacterially produced sulfide precipitated as FeS but was not completely responsible for Fe reduction. The separation of oxidized Fe particles from bacteria by dialysis tubing demonstrated that direct bacterial contact was necessary for Fe reduction. Fe reduction in cultures amended with NO3− was delayed until NO3− and NO2− were removed. However, bacterial attachment to oxidized Fe particles in NO3−-amended cultures occurred early during growth in a manner similar to NO3−-free cultures. During late stages of growth, bacteria not attached to Fe particles became pale and swollen, while attached cells remained bright blue when examined by 4′,6-diamidine-2-phenylindole epifluo-rescence microscopy. The presence of added oxidized Mn had no effect on Fe reduction. The results suggested that enzymatic Fe reduction was responsible for reducing Fe in these cultures even in the presence of sulfide and that cells incapable of Fe reduction became unhealthy when Fe(III) was the only available electron acceptor.

U-Pb AGES OF ZIRCONS FROM THE GRÃO-PARÁ GROUP AND SERRA DOS CARAJÁS GRANITE, PARÁ, BRAZIL

Abstract: Zircons collected from weathered rhyolites in the lower metavolcanic sequence of the Grao-Para Group yield a U-Pb upper lntercept age of 2,758 ± Ma. The zircons show no sign of a premagmatic history, and the age is interpreted as the age of volcanism. This Archean agels within the calculated uncertainty of a Rb-Sr whole-rock isochron age for interstratified basalts, reported separately. The U-Pb age is the first indication that the Grao-Para Group, including the Carajas Formation iron deposits, is Archean, much older than previously thought. Zircons were also collected from weathered Serra dos Carajas .Granite adjacent to the quarry near Serra Norte. These yield a U-Pb age of 1,820 ± 49 Ma, which agrees well with previously published age determinations for the granite, and for the Uatuma Supergroup volcanic and shallow plutonic rocks that occur throughout the Amazonian Craton. Zircons from both the Grâo-Para rhyolite and Carajas Granite show evidence for a single stage loss of radiogenic lead, possibly due to dilatancy during Mesozoic uplift of the region. All of the zircons were panned from saprolites, and most exhibit well-defined crystal forms. Tropical weathering is an asset to the collection and field concentration of zircons, and our results confirm that standard U-Pb dating techniques can be successfully applied in deeply-weathered terranes.

Photoperiodic regulation of gametogenesis in a North Atlantic sea star, Asterias vulgaris

Abstract: Summary Individuals of the sea star Asterias vulgaris from New Hampshire were maintained under two contrasting regimes of seasonally changing photoperiod. In one regime the lights turned on and off in phase with local sunrise and sunset; in the other, the daily photoperiod was kept 6 months out of phase with ambient photo- period. When dissected after being maintained for 18 months, the gametogenic condition of the out-of-phase animals was found to be 6 months out of phase with that of the in-phase animals. This experiment demonstrates that photoperiodic regulation of reproduction is important even in marine animals that normally experience marked seasonal changes in sea temperature.

Proposed pathogenic mechanism for the diarrhea associated with human intestinal spirochetes.

Abstract: Spirochetes resembling Brachyspira aalborgi were found in the feces and rectal biopsies of a patient with persistent diarrhea. Although the organism failed to grow on bacteriologic media, it was found attached to the surfaces of the epithelial cells on the rectal lumen. Blunting and destruction of the cellular microvilli was evident. These induced pathologic cell surface changes, together with the presence of intracellular bacteria in the cells of the rectal colon, suggest a pathogenic mechanism for the persistent diarrhea often associated with this condition. Both the spirochetosis and clinical symptoms disappeared on treatment with metronidazole.

Monitoring Spruce Budworm (Lepidoptera: Tortricidae) Populations with Pheromone-baited Traps

Abstract: Field trials with four types of pheromone traps and two types of commercial lures were evaluated to develop a population-monitoring technique for spruce bud worm, Choristoneura fumiferana (Clemens). When data were stratified by state or province, mean catch in several treatments (trap model/lure combinations) was significantly correlated with densities of larval stages L3–L4 (generations n and n + 1) and L2. Relationships varied among regions and hosts. There was no significant difference in moth catch between traps within five-trap clusters when traps were spaced 40 m apart. Within-cluster variation in trap catch was high; coefficients of variation averaged 35% for the covered funnel trap/Conrel lure treatment and 49% for the covered funnel trap/Hercon lure treatment. Application of pheromone-baited traps to monitor spruce budworm populations is discussed and recommendations are made to improve the monitoring system.

Pollination Intensity, Fruit Maturation Pattern, and Offspring Quality in Cassia fasciculata (Leguminosae)

Abstract: Individuals of many seed plants produce more pistillate flowers and initiate more fruits than they can mature with available resources; thus flower and fruit abortion are common (Stephenson 1981). Relatively little is known, however, about the factors that determine which flowers give rise to mature fruits and which do not. In some species, such as Cassia fasciculata (Leguminosae), flowers receiving light pollen loads (few grains/stigma) are less likely to produce mature fruits than those receiving heavy loads (Lee and Bazzaz 1982).

The interaction of tidal currents on a disturbed intertidal bottom with a resulting change in particulate matter quantity, texture and food quality

Abstract: The purpose of this investigation was to determine if clam digging had an effect on the suspended sediment texture and composition in the intertidal zone. Surface sediment and suspended particulate samples were collected prior to and after bottom perturbation similar to clam digging. The results indicated that the dug bottom sediments became coarser and contained lower amounts of organic matter. The coarser texture was due to increased winnowing on the ‘rough’ bottom created in the digging process. Suspended sediment concentrations also increased after perturbation, especially over finer-textured areas. The resuspended particulates were well sorted with relatively low organic content. Resuspended bottom sediments contributed virtually no protein to the particulates brought in by the estuarine waters. Recovery rate both of the bottom sediments and the suspended particulates was slow, and seemed dependent on the microtopographic relief which could take weeks to months to return to normal.