Showing papers by "University of New Hampshire published in 1999"
TL;DR: The Multifactor Emotional Intelligence Scale (MEIS) as discussed by the authors is a 12-sub-scale ability test of emotional intelligence, which measures the ability of an individual with respect to a set of abilities.
2,644 citations
Book•
29 Jan 1999TL;DR: A penetrating study of the 1962 Cuban missile crisis examines the workings of American decision-making and foreign policy as mentioned in this paper, and examines the inner workings of the United States' decisionmaking and its foreign policy.
Abstract: A penetrating study of the 1962 Cuban missile crisis examines the workings of American decision-making and foreign policy.
1,571 citations
TL;DR: A comparison of 17 global models of terrestrial biogeochemistry with respect to annual and seasonal fluxes of net primary productivity (NPP) for the land biosphere is presented in this article.
Abstract: Seventeen global models of terrestrial biogeochemistry were compared with respect to annual and seasonal fluxes of net primary productivity (NPP) for the land biosphere. The comparison, sponsored by IGBP-GAIM/DIS/GCTE, used standardized input variables wherever possible and was carried out through two international workshops and over the Internet. The models differed widely in complexity and original purpose, but could be grouped in three major categories: satellite-based models that use data from the NOAA/AVHRR sensor as their major input stream (CASA, GLO-PEM, SDBM, SIB2 and TURC), models that simulate carbon fluxes using a prescribed vegetation structure (BIOME-BGC, CARAIB 2.1, CENTURY 4.0, FBM 2.2, HRBM 3.0, KGBM, PLAI 0.2, SILVAN 2.2 and TEM 4.0), and models that simulate both vegetation structure and carbon fluxes (BIOME3, DOLY and HYBRID 3.0). The simulations resulted in a range of total NPP values (44.4‐66.3 Pg C year ‐1 ), after removal of two outliers (which produced extreme results as artefacts due to the comparison). The broad global pattern of NPP and the relationship of annual NPP to the major climatic variables coincided in most areas. Differences could not be attributed to the fundamental modelling strategies, with the exception that nutrient constraints generally produced lower NPP. Regional and global NPP were sensitive to the simulation method for the water balance. Seasonal variation among models was high, both globally and locally, providing several indications for specific deficiencies in some models.
979 citations
TL;DR: Regular smokers were more impulsive than never smokers using personality and behavioral measures of impulsivity, and smokers had statistically higher impulsivity scores on most scales.
Abstract: Rationale: Drug users are thought to be more ”impulsive” than non-users. Objectives: This study examined whether regular smokers are more impulsive than never smokers using personality and behavioral measures of impulsivity. Methods: Twenty regular smokers (≥15 cigarettes/day) and 20 never smokers were recruited. Participants completed five personality questionnaires to assess impulsivity: Adjective Checklist, Barratt’s Impulsivity Scale, the Tridimensional Personality Questionnaire, Eysenck’s Personality Questionnaire, and the Sensation-Seeking Scale. Participants also performed three behavioral choice tasks designed to assess impulsivity. In the delay task, participants chose between small, immediate and large, delayed monetary rewards. Impulsivity was defined as a relative preference for the small, immediate alternative. In the probability task, participants chose between small, certain and large, uncertain monetary rewards. Impulsivity was defined as a relative preference for the large but more risky alternative. In the work task, participants chose between small monetary rewards obtained by performing a negligible amount of work and a larger amount of money requiring more work. Impulsivity was defined as a relative preference for the smaller, easier alternative. Results: On the personality questionnaires, smokers had statistically higher impulsivity scores on most scales. On the behavioral choice tasks, smokers chose small, immediate money over large, delayed money more frequently, signifying greater levels of impulsivity. There were no differences between the groups’ choices on the other tasks. Correlations between questionnaire and task data were small, as were correlations between data from each task. Conclusions: Together, these results indicate that the smokers were more impulsive than never smokers.
913 citations
TL;DR: In this paper, the authors present a comprehensive compilation of the main statistical approaches to this problem, descriptions and characterizations of the underlying models, and discussions of related statistical methodologies for estimation and confidence-interval construction.
Abstract: In 1960, Cohen introduced the kappa coefficient to measure chance-corrected nominal scale agreement between two raters. Since then, numerous extensions and generalizations of this interrater agreement measure have been proposed in the literature. This paper reviews and critiques various approaches to the study of interrater agreement, for which the relevant data comprise either nominal or ordinal categorical ratings from multiple raters. It presents a comprehensive compilation of the main statistical approaches to this problem, descriptions and characterizations of the underlying models, and discussions of related statistical methodologies for estimation and confidence-interval construction. The emphasis is on various practical scenarios and designs that underlie the development of these measures, and the interrelationships between them.
894 citations
TL;DR: In this paper, the authors analyzed the maximum temperature data from 49 stations in Nepal for the period 1971-94 and revealed that the recent warming trends were preceded by similar widespread cooling trends.
Abstract: Analyses of maximum temperature data from 49 stations in Nepal for the period 1971‐94 reveal warming trends after 1977 ranging from 0.068 to 0.128 Cy r 21 in most of the Middle Mountain and Himalayan regions, while the Siwalik and Terai (southern plains) regions show warming trends less than 0.038 Cy r 21. The subset of records (14 stations) extending back to the early 1960s suggests that the recent warming trends were preceded by similar widespread cooling trends. Distributions of seasonal and annual temperature trends show high rates of warming in the high-elevation regions of the country (Middle Mountains and Himalaya), while low warming or even cooling trends were found in the southern regions. This is attributed to the sensitivity of mountainous regions to climate changes. The seasonal temperature trends and spatial distribution of temperature trends also highlight the influence of monsoon circulation. The Kathmandu record, the longest in Nepal (1921‐94), shows features similar to temperature trends in the Northern Hemisphere, suggesting links between regional trends and global scale phenomena. However, the magnitudes of trends are much enhanced in the Kathmandu as well as in the all-Nepal records. The authors’ analyses suggest that contributions of urbanization and local land use/cover changes to the all-Nepal record are minimal and that the all-Nepal record provides an accurate record of temperature variations across the entire region.
800 citations
TL;DR: Spectroscopic studies have shown that a di-Fe(III) peroxo intermediate is produced at the ferroxidase site followed by formation of a mu-oxobridged dimer, which then fragments and migrates to the nucleation sites to form incipient mineral core species.
748 citations
TL;DR: In this article, the authors examined previously published seagrass research through a lens of global climate change in order to consider the potential effects of sea level rise on the world's seagras.
680 citations
TL;DR: Schimel et al. as discussed by the authors described a blueprint for more comprehensive coordination of various flux measurement and modeling activities into a global terrestrial monitoring network that will have direct relevance to the political decision making of global change.
629 citations
TL;DR: In this paper, the nitrogen stable isotopic composition of tree leaves and soils from a variety of tropical and temperate forests was compared, and it was shown that tropical forests are relatively more 15N enriched than temperately forests.
Abstract: Several lines of evidence suggest that nitrogen in most tropical forests is relatively more available than N in most temperate forests, and even that it may function as an excess nutrient in many tropical forests. If this is correct, tropical forests should have more open N cycles than temperate forests, with both inputs and outputs of N large relative to N cycling within systems. Consequent differences in both the magnitude and the pathways of N loss imply that tropical forests should in general be more 15N enriched than are most temperate forests. In order to test this hypothesis, we compared the nitrogen stable isotopic composition of tree leaves and soils from a variety of tropical and temperate forests. Foliar γ15N values from tropical forests averaged 6.5%0 higher than from temperate forests. Within the tropics, ecosystems with relatively low N availability (montane forests, forests on sandy soils) were significantly more depleted in 15N than other tropical forests. The average γ15N values for tropical forest soils, either for surface or for depth samples, were almost 8%o higher than temperate forest soils. These results provide another line of evidence that N is relatively abundant in many tropical forest ecosystems.
548 citations
TL;DR: In this article, the authors report that the dissimilatory iron-reducing bacterium Shewanella alga strain BrY promoted As mobilization from a crystalline ferric arsenate as well as from sorption sites within whole sediments.
Abstract: The mobility of arsenic commonly increases as reducing conditions are established within sediments or flooded soils. Although the reduction of arsenic increases its solubility at circumneutral pH, hydrous ferric oxides (HFO) strongly sorb both As(V) (arsenate) and As(III) (arsenite), the two primary inorganic species. Thus, in the presence of excess HFO, reductive dissolution of iron may be the dominant mechanism by which As is released into solution. In this paper, we report that the dissimilatory iron-reducing bacterium Shewanella alga strain BrY promoted As mobilization from a crystalline ferric arsenate as well as from sorption sites within whole sediments. S. alga cells released arsenate from the mineral scorodite (FeAsO4·2H2O) as a result of dissimilatory (i.e., respiratory) reduction of Fe(III) to Fe(II). Solid-phase analysis with SEM-EDS and XAFS (X-ray absorption fine structure) spectroscopy revealed that the valence states of Fe and As in the solid-phase product were identical to those in soluti...
TL;DR: In this article, the authors consider right-censored survival data for populations with a surviving (cure) fraction and propose a model that is quite different from the standard mixture model for cure rates.
Abstract: We consider Bayesian methods for right-censored survival data for populations with a surviving (cure) fraction. We propose a model that is quite different from the standard mixture model for cure rates. We provide a natural motivation and interpretation of the model and derive several novel properties of it. First, we show that the model has a proportional hazards structure, with the covariates depending naturally on the cure rate. Second, we derive several properties of the hazard function for the proposed model and establish mathematical relationships with the mixture model for cure rates. Prior elicitation is discussed in detail, and classes of noninformative and informative prior distributions are proposed. Several theoretical properties of the proposed priors and resulting posteriors are derived, and comparisons are made to the standard mixture model. A real dataset from a melanoma clinical trial is discussed in detail.
TL;DR: In this article, the porosimetry was performed on 92 hardened cement paste specimens of water/cement (w/c) ratios 0.3, 0.4, 0 4, 0 5, 0 6, 0 7, 14, 28, and 56 days.
TL;DR: In this article, the authors extend previous investigations in two ways: first, the analysis is conducted using business unit-level data, which reduces the aggregation problem that is likely to arise using firm level data; and second, managers in this setting are paid bonuses based solely on business unit earnings.
TL;DR: In this paper, the authors assess the likely direct and indirect effects of increasing anthropogenic N inputs on tropical ecosytem processes and conclude that anthropogenic inputs of N into tropical forests are unlikely to increase productivity and may even decrease it.
Abstract: Human activities have more than doubled the inputs of nitrogen (N) into terrestrial systems globally. The sources and distribution of anthropogenic N, including N fertilization and N fixed during fossil fuel combustion, are rapidly shifting from the temperate zone to a more global distribution. The consequences of anthropogenic N deposition for ecosystem processes and N losses have been studied primarily in N-limited ecosystems in the temperate zone; there is reason to expect that tropical ecosystems, where plant growth is most often limited by some other resource, will respond differently to increasing deposition. In this paper, we assess the likely direct and indirect effects of increasing anthropogenic N inputs on tropical ecosytem processes. We conclude that anthropogenic inputs of N into tropical forests are unlikely to increase productivity and may even decrease it due to indirect effects on acidity and the availability of phosphorus and cations. We also suggest that the direct effects of anthropogenic N deposition on N cycling processes will lead to increased fluxes at the soil-water and soil-air interfaces, with little or no lag in response time. Finally, we discuss the uncertainties inherent in this analysis, and outline future research that is needed to address those uncertainties.
TL;DR: In this article, a model of the global troposphere was used to examine the pre-industrial and contemporary quantities and spatial patterns of wet and dry NOy and NHX deposition.
Abstract: Increases and expansion of anthropogenic emissions of both oxidized nitrogen compounds, NOX, and a reduced nitrogen compound, NH3, have driven an increase in nitrogen deposition. We estimate global NOX and NH3 emissions and use a model of the global troposphere, MOGUNTIA, to examine the pre-industrial and contemporary quantities and spatial patterns of wet and dry NOy and NHX deposition. Pre-industrial wet plus dry NOX and NHX deposition was greatest for tropical ecosystems, related to soil emissions, biomass burning and lightning emissions. Contemporary NOy + NHX wet and dry deposition onto Northern Hemisphere (NH) temperate ecosystems averages more than four times that of preindustrial N deposition and far exceeds contemporary tropical N deposition. All temperate and tropical biomes receive more N via deposition today than pre-industrially. Comparison of contemporary wet deposition model estimates to measurements of wet deposition reveal that modeled and measured wet deposition for both and were quite similar over the U.S. Over Western Europe, the model tended to underestimate wet deposition of and but bulk deposition measurements were comparable to modeled total deposition. For the U.S. and Western Europe, we also estimated N emission and deposition budgets. In the U.S., estimated emissions exceed interpolated total deposition by 3–6 Tg N, suggesting that substantial N is transported offshore and/or the remote and rural location of the sites may fail to capture the deposition of urban emissions. In Europe, by contrast, interpolated total N deposition balances estimated emissions within the uncertainty of each.
TL;DR: It is demonstrated that adaptive divergence in trophic morphology played an important role during the early history of the lake, which suggests that other forces are responsible for the continued speciation of these fishes.
Abstract: Lake Malawi contains a flock of >500 species of cichlid fish that have evolved from a common ancestor within the last million years. The rapid diversification of this group has been attributed to morphological adaptation and to sexual selection, but the relative timing and importance of these mechanisms is not known. A phylogeny of the group would help identify the role each mechanism has played in the evolution of the flock. Previous attempts to reconstruct the relationships among these taxa using molecular methods have been frustrated by the persistence of ancestral polymorphisms within species. Here we describe results from a DNA fingerprinting technique that overcomes this problem by examining thousands of polymorphisms distributed across the genome. The resulting dendrogram averages the evolutionary history of thousands of genes and should accurately reflect the evolutionary history of these species. Our tree resolves relationships among closely related Lake Malawi cichlids and provides insights into the pattern of speciation in this group. We demonstrate that adaptive divergence in trophic morphology played an important role during the early history of the lake. Subsequent species diversity has arisen with little change in trophic morphology, which suggests that other forces are responsible for the continued speciation of these fishes.
Journal Article•
TL;DR: The authors found evidence consistent with Healy (1985) that managers with bonus-related incentives to make income-increasing discretionary accruals do so relative to managers with incentives to use accrual discretion to decrease earnings.
TL;DR: In this article, the interstitial air of surface snow and in ambient air at Summit, Greenland, were determined in a manner consistent with photochemical generation within the snowpack, and the observed release of NOx may have been initiated by photolysis of nitrate, present in relative abundance in surface snow at Summit.
Abstract: NOx and NOy were determined in the interstitial air of surface snow and in ambient air at Summit, Greenland. NOx levels in interstitial air were 3 to >10 times those in ambient air, and were generally greater than ambient NOy levels. [NOy] in interstitial air varied diurnally in a manner consistent with photochemical generation within the snowpack. These observations imply that photochemical reactions occurring within or upon the ice crystals of surface snow produced NOx from a N-reservoir compound within the snow. Average [NOx]:[HNO3] and [NOx]:[NOy] ratios in ambient air above the snow were elevated relative to other remote sites, indicating that NOx release within the snowpack may have altered NOx levels in the overlying atmospheric boundary layer. We suggest that the observed release of NOx may have been initiated by photolysis of nitrate, present in relative abundance in surface snow at Summit. Such a process may affect levels of nitrate and other compounds in surface snow, the overlying atmosphere, and glacial ice, and its potential role in cirrus cloud chemistry should be investigated.
TL;DR: The study found that the group provided many of the processes used in face-to-face self-help and mutual aid groups, with an emphasis on mutual problem solving, information sharing, expression of feelings, catharsis, and mutual support and empathy.
Abstract: The number of US citizens with temporary or lifetime disabilities constitutes a large segment of the population It is estimated that there are as many as 24 million people with a severe disabling condition (International Center for Disability Information, 1999), including 7,500 people with spinal chord injuries per year, 750,000 people with cerebral palsy, 200,000 with muscular dystrophy, and more than 5 million with severe arthritis Nationally, there are an estimated 17 million people with disabilities who are homebound and an additional 125 million who are temporarily homebound There also are many caretakers of disabled and elderly people who are essentially homebound as a result of their responsibilities at home In addition to the physical and emotional difficulties directly associated with disability, a number of social and emotional difficulties result from being alienated or "socially quarantined" from the larger society: depression, loneliness, alienation, lack of social interaction, lack of information, and lack of access to employment (Braithwaite, 1996; Coleman, 1997; Shworles, 1983) Online groups - self-help and mutual aid groups - found on Internet newsgroups, commercial information networks, and computer bulletin boards are potential resources to this large population because they combine the advantages of self-help and the accessibility of computer networks Given the limited number of trained leaders and the relative scarcity of services, online groups could provide an important adjunct to in-person services as part of a wait-list condition, as a source of concurrent support, and as follow-up to time-limited groups (Finn, 1995) Although the existence of online groups has been documented, there are very limited research and anecdotal reports about the types of help offered or the content of the information shared among members Self-Help and Mutual Aid Groups Self-help groups have been described as an essential human resource and a permanent social utility (Katz, 1992) The groups are an attempt by people with a mutual problem to take control over circumstances that affect their lives In general, self-help groups are based on principles of empowerment, inclusion, nonhierarchical decision making, shared responsibility, and a holistic approach to people's cultural, economic, and social needs Their values include cooperative self-organization, nonbureaucratic mutual helping methods, social support, and free services (Schopler & Galinsky, 1993; Segal, Silverman, & Ternkin, 1993) It has been estimated that there are 400 distinct types of self-help groups, comprising 500,000 groups in the United States, attended by more than 15 million people The number of groups has quadrupled in past the 15 years (Boreman, Brock, Hess, & Pasquale, 1982; Kessler, Mickelson, & Zhao, 1997; Leechsen, Lewis, Pomer, Davenport, & Nelson, 1990) The health care arena has seen exponential growth in self-help groups since the early 1980s Group membership includes people and their families suffering from chronic disease, people requiring long-term rehabilitation, people experiencing terminal illness and bereavement, and people recovering from addiction Factors that have promoted the development of self-help groups include insufficient health care resources for some populations, rising cost of health care, lack of support within the medical system for chronic conditions, growing distrust of medical professionals, increased interest in alternative medicine, a new emphasis on prevention, and a rise in consumer consciousness (Riessman & Carroll, 1995) The research evidence points to the positive outcomes of self-help participation (Ayers, 1989; Furlong, 1989; Gottlieb, 1982; Gottlieb, 1985; Kyrouz & Humphreys, 1998; Lipson, 1982; Yalom, 1985) A considerable amount of research has been undertaken in defining the kind of help that self-help groups can provide and the theoretical reasons for their success …
TL;DR: The use of mitochondrial genomes for studying such deep divergences is coming under increased scrutiny, and these novel results need to be confirmed with data from nuclear genes.
Abstract: Mitochondrial genomes are being used to study increasingly ancient divergences among animal groups. Recent studies of complete mitochondrial DNA sequences have arrived at somewhat heretical conclusions, raising questions about the use of mitochondrial gene sequences for studying the relationships among highly divergent lineages. Other studies have documented convergent evolution of mitochondrial gene order, casting doubt on the use of these characters for phylogenetic analysis. The use of mitochondrial genomes for studying such deep divergences is coming under increased scrutiny, and these novel results need to be confirmed with data from nuclear genes.
TL;DR: Carbon dioxide, water vapour, and sensible heat fluxes were measured above and within a spruce dominated forest near the southern ecotone of the boreal forest in Maine, USA as mentioned in this paper.
Abstract: Carbon dioxide, water vapour, and sensible heat fluxes were measured above and within a spruce dominated forest near the southern ecotone of the boreal forest in Maine, USA.
TL;DR: In this article, the authors used the Greenland Ice Sheet Project 2 (GISP2) ice core to provide a calendrical age of 7627 ± 150 cal yr B.P. (5677 ± 150 B.C.) for the eruption of Mount Mazama, thus providing a more accurate early Holocene stratigraphic time line.
Abstract: Geochemical identification of Mount Mazama ash in the Greenland Ice Sheet Project 2 (GISP2) ice core gives a calendrical age of 7627 ± 150 cal yr B.P. (5677 ± 150 B.C.) for the eruption, thus providing a more accurate early Holocene stratigraphic time line than previously available. The GISP2 record of volcanically derived sulfate suggests a total stratospheric aerosol loading between 88 and 224 Mt spread over an ∼6 yr period following the eruption of Mount Mazama. Taking into account the likelihood of some tropospheric aerosol transport to Greenland, realistic estimates of the resulting atmospheric optical depth range from 0.6 to 1.5. These values may have produced a temperature depression of ∼0.6 to 0.7 °C at mid to high northern latitudes for 1–3 yr after the eruption. These results indicate that the 5677 B.C. eruption of Mount Mazama was one of the most climatically significant volcanic events of the Holocene in the Northern Hemisphere. We also calculate a maximum stratospheric Cl − release of 8.1 Mt by the eruption, which may have led to substantial stratospheric ozone depletion.
TL;DR: What information is available from analytical ultracentrifugation and how that information is being extracted and used in contemporary applications are stressed.
Abstract: Analytical ultracentrifugation is a classical method of biochemistry and molecular biology. Because it is a primary technique, sedimentation can provide first-principle hydrodynamic and first-principle thermodynamic information for nearly any molecule, in a wide range of solvents and over a wide range of solute concentrations. For many questions, it is the technique of choice. This review stresses what information is available from analytical ultracentrifugation and how that information is being extracted and used in contemporary applications.
TL;DR: Comparisons of girls versus boys and sisters versus brothers revealed that differences in children's sex-typing as a function of fathers' attitudes and sibling sex constellation were most apparent for children's activities.
Abstract: We studied the extent of sex-typing across different areas of child functioning (personality, interests, activities) in middle childhood as a function of the traditionality of parents' gender role attitudes and the sex composition of the sibling dyad. Participants included 200 firstborn children (mean = 10.4 years old), their secondborn siblings (mean = 7.7 years old) and their mothers and fathers. Family members were interviewed in their homes about their attitudes and personal characteristics and completed a series of seven evening telephone interviews about their daily activities. We measured children's attitudes, personality characteristics, and interests in sex-typed leisure activities (e.g., sports, handicrafts) as well as time spent in sex-typed leisure activities and household tasks (e.g., washing dishes, home repairs) and with same and opposite sex companions (i.e., parents, peers). Analyses revealed that sex-typing was most evident in children's interests and activities. Further, comparisons of girls versus boys and sisters versus brothers revealed that differences in children's sex-typing as a function of fathers' attitudes and sibling sex constellation were most apparent for children's activities. A notable exception was sex-typed peer involvement; time spent with same versus opposite sex peers was impervious to context effects. Analyses focused on children's sex-typing as a function of mothers' attitudes generally were nonsignificant.
TL;DR: This article found that the ethnic compositions of 55 urban and 57 rural charter schools were inspected relative to their traditional public school neighbors in Arizona's most populated region and its rural towns in 1996-97.
Abstract: Among the criticisms of charter schools is their potential to further stratify schools along ethnic and class lines. This study addressed whether Arizona charter schools are more ethnically segregated than traditional public schools. In 1996-97, Arizona had nearly one in four of all charter schools in the United States. The analysis involved a series of comparisons between the ethnic compositions of adjacent charter and public schools in Arizona's most populated region and its rural towns. This methodology differed from the approach of many evaluations of charter schools and ethnic stratification in that it incorporated the use of geographic maps to compare schools' ethnic make-ups. The ethnic compositions of 55 urban and 57 rural charter schools were inspected relative to their traditional public school neighbors.
TL;DR: In this paper, the authors analyzed the effect of anthropogenic disturbance of the nitrogen cycle, either through land use or atmospheric deposition, on the yield of fixed nitrogen and nitrogen fractions in thirty-one watersheds.
Abstract: Yields of total fixed nitrogen and nitrogen fractions are summarized for thirty-one watersheds in which anthropogenic disturbance of the nitrogen cycle, either through land use or atmospheric deposition, is negligible or slight. These yields are taken as representative of background conditions over a broad range of watershed areas, elevations, and vegetation types. The data set focuses on watersheds of the American tropics, but also includes information on the Gambia River (Africa) and some small watersheds in the Sierra Nevada of California. For the tropical watersheds, total nitrogen yield averages 5.1 kg ha -1 y-1. On average, 30% of the total is particulate and 70% is dissolved. Of the dissolved fraction, an average of 50% is organic and 50% is inorganic, of which 20% is ammonium and 80% is nitrate. Yields are substantially lower than previously estimated for background conditions. Yields of all nitrogen fractions are strongly related to runoff, which also explains a large percentage of variance in yield of total nitrogen (r2 = 0.85). For total nitrogen and nitrogen fractions, yield increases at about two-thirds the rate of runoff; concentration decreases as runoff increases. There is a secondary but significant positive relationship between elevation and yield of DIN. Ratios DONAIDN and PN/TN both are related to watershed area rather than runoff; DON/TDN decreases and PN/TN increases toward higher stream orders. The analysis suggests for tropical watersheds the existence of mechanisms promoting strong homeostasis in the yield of N and its fractions for a given moisture regime, as well as predictable downstream change in proportionate representation N fractions. Yields and concentrations for small tropical watersheds are much larger than for the few temperate ones with which comparisons are possible.
TL;DR: Fluorescence of dissolved proteinaceous materials was examined in two estuaries differing primarily in river input as mentioned in this paper, and low-wavelength excitation (220-230 nm) was found to be more useful than the high wavelength excitations (280 nm) usually reported in the literature.
TL;DR: In this paper, a time-dependent kinetic model is used to investigate the relative importance of various mechanisms in the early phase decay rate of the ring current in both the solar maximum storm of June 4-7, 1991 and especially the solar minimum storm of September 24-27, 1998.
Abstract: A time-dependent kinetic model is used to investigate the relative importance of various mechanisms in the early phase decay rate of the ring current. It is found that, for both the solar maximum storm of June 4–7, 1991 and especially the solar minimum storm of September 24–27, 1998, convective drift loss out the dayside magnetopause is the dominant process in removing ring current particles during the initial recovery. During the 1998 storm, dayside outflow losses outpaced charge exchange losses by a factor of ten.
TL;DR: A quantitative model of the concurrent three-term contingency that is based on the notion that an animal's behavior is controlled to differing extents by both stimulus—behavior and behavior—reinforcer relations is discussed.
Abstract: We propose that a fundamental unit of behavior is the concurrent discriminated operant, and we discuss in detail a quantitative model of the concurrent three-term contingency that is based on the notion that an animal's behavior is controlled to differing extents by both stimulus—behavior and behavior—reinforcer relations. We show how this model can describe performance in a variety of experimental procedures: conditional discrimination and matching to sample, both with and without reinforcement for responses that are traditionally identified as errors; conditional discrimination with more than two stimuli and choice alternatives; delayed matching to sample and delayed reinforcement in matching to sample; second-order and complex conditional discrimination; and multiple and concurrent schedules. Although the model is incomplete in its coverage, and may be incorrect, we believe that this conceptual approach will bear fruit in the development of behavior theory.