An Exploratory Study of Hypermedia Support for Problem Decomposition

Empirical hypermedia research has concentrated on usability rather than utility, and the research on utility has focused on information access as opposed to problem solving and decision making in organizations. This study, based on problem reduction theory, uses a hypermedia prototype system to support decision processes for solving a financial analysis problem. An exploratory laboratory experiment was conducted to study the feasibility of the prototype for hypermedia support of decision making. The process tracing techniques used suggest that a cognitive map of a decision maker\u27s thought process may be constructed. Results offer a great deal of promise in the use of hypermedia for organizational decision support. The implications of this study for further research are discussed

Measuring the Effectiveness of Hypertext In Decision Support

Hypertext is an emerging technology that has not been researched adequately, particularly in organizations that utilize decision support technologies. This paper suggests that developing a set of dependent variables to measure effectiveness of hypertext in decision support is an important first step in a program of research. A review of empirical hypertext research is presented followed by a discussion of research assessing effectiveness of decision support and related systems. The role of hypertext in organizations is conceptually linked to the three main phases of the decision making process: problem structuring, analysis, and problem resolution. A set of six classes of appropriate dependent variables for assessing effectiveness of hypertext is suggested within the context of the decision making phases: information content and function variables are associated with problem structuring; presentation and usage variables are associated with analysis; outcome and perception variables are associated with problem resolution

The All New This Old South

Recent claims concerning the rise of the Sunbelt closely resemble those previously made about the New South. It is assumed that the South has finally broken the ties of dependency with the North and has embarked on a remarkable path of self-sustained growth. In fact, this growth in the South is considered to be largely at the expense of the North. These and other similar claims are based on five assumptions about the South: 1) An economic transformation has occurred in the region; 2) absentee ownership is minimal; 3) benefits of economic growth has been diffused to most segments of the population; 4) economic growth has reduced poverty and inequality in the region; and 5) government spending has spurred much of the region\u27s growth. These assumptions form the basis of the diffusion model of economic-industrial development. Examining these assumptions in light of available data, however, places in question the validity of claims made about the Sunbelt

Using art to assess environmental education outcomes

Construction of developmentally appropriate tools for assessing the environmental attitudes and awareness of young learners has proven to be challenging. Art-based assessments that encourage creativity and accommodate different modes of expression may be a particularly useful complement to conventional tools (e.g. surveys), but their efficacy and feasibility across diverse contexts has not been adequately explored. To examine the potential utility of integrating art into evaluations of environmental education outcomes, we adapted an existing drawing prompt and corresponding grading rubric to assess the environmental attitudes and awareness of children (ages 6–12) at summer camps in Athens, GA, USA (n = 285). We then compared children’s drawings with scores on a more typical survey instrument that measured similar outcomes, the Children Environmental Perception’s Scale. Results showed that a drawing prompt was a practical and unique learner-centered tool for measuring distinct components of environmental attitudes and awareness. Findings also revealed different response patterns across the two instruments, highlighting the value of using multiple approaches (e.g. art-based and survey-based) to assess cognitive and affective aspects of children’s environmental orientations

Economic Dualism in American Agriculture

Renewed interest in agriculture by sociologists has led to an emphasis on structural analyses of rural America. Drawing upon the dual economy model, this paper proposes an alternative concept of the changing structure of agriculture in the United States. Two industrial sectors--the core and the periphery--are defined, and their relevance to agriculture is explored. Following Averitt, agriculture is an industry which historically has had a periphery-type orientation but is now undergoing encroachment from the core economy and partially from domination by the federal government. The research implications of the dual economy model for rural sociology are discussed

Local awareness of and attitudes toward pygmy hippopotamus conservation in the Moa River Island Complex, Sierra Leone.

Abstract The pygmy hippopotamus Choeropsis liberiensis is an Endangered species found only in the Upper Guinea rainforests of West Africa. Using a two-phase approach, with initial semi-structured interviews followed by more extensive questionnaires, we examined local residents’ awareness of and attitudes towards the pygmy hippopotamus along the Moa River near Tiwai Island Wildlife Sanctuary in Sierra Leone. The interviews and questionnaires addressed human–hippopotamus interactions, local knowledge and awareness of pygmy hippopotamus ecology and behaviour, and public attitudes towards hippopotamus conservation. Overall, 22% of questionnaire respondents acknowledged benefits related to hippopotamus conservation; factors affecting the perception of benefits included age, livestock ownership, distance from Tiwai Island and exposure to conservation programmes. The results of this study could be used to inform the conservation of the pygmy hippopotamus and highlight the critical role of local support in the management of threatened species in biodiversity hotspots

Stimulus Variability Affects the Amplitude of the Auditory Steady-State Response

In this study we investigate whether stimulus variability affects the auditory steady-state response (ASSR). We present cosinusoidal AM pulses as stimuli where we are able to manipulate waveform shape independently of the fixed repetition rate of 4 Hz. We either present sounds in which the waveform shape, the pulse-width, is fixed throughout the presentation or where it varies pseudo-randomly. Importantly, the average spectra of all the fixed-width AM stimuli are equal to the spectra of the mixed-width AM. Our null hypothesis is that the average ASSR to the fixed-width AM will not be significantly different from the ASSR to the mixed-width AM. In a region of interest beamformer analysis of MEG data, we compare the 4 Hz component of the ASSR to the mixed-width AM with the 4 Hz component of the ASSR to the pooled fixed-width AM. We find that at the group level, there is a significantly greater response to the variable mixed-width AM at the medial boundary of the Middle and Superior Temporal Gyri. Hence, we find that adding variability into AM stimuli increases the amplitude of the ASSR. This observation is important, as it provides evidence that analysis of the modulation waveform shape is an integral part of AM processing. Therefore, standard steady-state studies in audition, using sinusoidal AM, may not be sensitive to a key feature of acoustic processing

Equivalence of arterial and venous blood for [11C]CO2-metabolite analysis following intravenous administration of 1-[11C]acetate and 1-[11C]palmitate

PURPOSE: Sampling of arterial blood for metabolite correction is often required to define a true radiotracer input function in quantitative modeling of PET data. However, arterial puncture for blood sampling is often undesirable. To establish whether venous blood could substitute for arterial blood in metabolite analysis for quantitative PET studies with 1-[(11)C]acetate and 1-[(11)C]palmitate, we compared the results of [(11)C]CO2-metabolite analyses performed on simultaneously collected arterial and venous blood samples. METHODS: Paired arterial and venous blood samples were drawn from anesthetized pigs at 1, 3, 6, 8, 10, 15, 20, 25 and 30min after i.v. administration of 1-[(11)C]acetate and 1-[(11)C]palmitate. Blood radioactivity present as [(11)C]CO2 was determined employing a validated 10-min gas-purge method. Briefly, total blood (11)C radioactivity was counted in base-treated [(11)C]-blood samples, and non-[(11)C]CO2 radioactivity was counted after the [(11)C]-blood was acidified using 6N HCl and bubbled with air for 10min to quantitatively remove [(11)C]CO2. RESULTS: An excellent correlation was found between concurrent arterial and venous [(11)C]CO2 levels. For the [(11)C]acetate study, the regression equation derived to estimate the venous [(11)C]CO2 from the arterial values was: y=0.994x+0.004 (r(2)=0.97), and for the [(11)C]palmitate: y=0.964x-0.001 (r(2)=0.9). Over the 1-30min period, the fraction of total blood (11)C present as [(11)C]CO2 rose from 4% to 64% for acetate, and 0% to 24% for palmitate. The rate of [(11)C]CO2 appearance in venous blood appears similar for the pig model and humans following i.v. [(11)C]-acetate administration. CONCLUSION: Venous blood [(11)C]CO2 values appear suitable as substitutes for arterial blood samples in [(11)C]CO2 metabolite analysis after administration of [(11)C]acetate or [(11)C]palmitate ADVANCES IN KNOWLEDGE AND IMPLICATIONS FOR PATIENT CARE: Quantitative PET studies employing 1-[(11)C]acetate and 1-[(11)C]palmitate can employ venous blood samples for metabolite correction of an image-derived tracer arterial input function, thereby avoiding the risks of direct arterial blood sampling

The magnetic field topology associated to two M flares

On 27 October, 2003, two GOES M-class flares occurred in the lapse of three hours in active region NOAA 10486. The two flares were confined and their associated brightenings appeared at the same location, displaying a very similar shape both at the chromospheric and coronal levels. We focus on the analysis of magnetic field (SOHO/MDI), chromospheric (HASTA, Kanzelhoehe Solar Observatory, TRACE) and coronal (TRACE) observations. By combining our data analysis with a model of the coronal magnetic field, we compute the magnetic field topology associated to the two M flares. We find that both events can be explained in terms of a localized magnetic reconnection process occurring at a coronal magnetic null point. This null point is also present at the same location one day later, on 28 October, 2003. Magnetic energy release at this null point was proposed as the origin of a localized event that occurred independently with a large X17 flare on 28 October, 2003, at 11:01 UT. The three events, those on 27 October and the one on 28 October, are homologous. Our results show that coronal null points can be stable topological structures where energy release via magnetic reconnection can happen, as proposed by classical magnetic reconnection models.Comment: 14 pages, 7 figure