The coronary arteries of the Bantu heart

No Abstrac

Embodying conversational characteristics in a graphical user interface

In the history of Intelligent Tutoring Systems, SOPHIE (Brown, Burton, and Bell, 1974), now considered a classic, contained many important ideas and features. One of these was its natural language user interface. Today, the trend has moved away from natural language interfaces towards graphical ones although the argument in favour of natural language user interfaces, both from Human Computer Interaction and natural language researchers, still persist. Is this argument correct? This thesis explores this question by investigating how SOPHIE might be re-implemented with a graphical direct manipulation interface instead of a natural language one, with the goal of improving its standard of usability. It begins by analysing the features that seem to have been central to SOPHIE's usability. These, it argues, were not so much an ability to accept well formed complete English sentences, as an ability to accept and interpret correctly a wide range of abbreviated inputs. Two models of interaction, Circuit 1, a pilot, and Circuit II, a fairly full implementation of SOPHIE were implemented and tested. Both employ free-order syntax that allows users to specify the components of a full command in any order. The combination of deixis and free-order syntax supported allows completely general ellipsis which achieves, in extended interaction sequences, the same economy and naturalness that SOPHIE achieved through its use of anaphora and ellipsis. Whilst the free-order syntax. technique is little used at present in user interfaces, the results of observational studies conducted have shown that it saves users time and convenience. Thus, considering key linguistic features of a natural language user interface has shown how novel features can enhance the usability of direct manipulation interfaces. This thesis argues that user interfaces can be improved by employing structures found in natural language or at least conversation which can be constructed within direct manipulation interface styles. This approach was further expanded to support topic shifts between different circuit contexts. Circuit II, like SOPHIE, supports three different topics: normal circuit behaviour, a circuit with an unknown fault, and circuits with user-hypothesised faults. Drawing on Reichman's (1981) work, Circuit II uses natural language cue phrases of the type "by the way", re-implemented in the direct manipulation style, to facilitate shifts between topics in a smoother and more natural way than SOPHIE which , used clumsy explicit commands

Optimum Stand Density of Spring Triticale for Grain Yield and Alfalfa Establishment

Triticale (×Triticosecale Wittmack) has potential as a feed crop in the north central United States and could also function as a companion crop for alfalfa (Medicago sativa L.) establishment. The objectives of this research were to assess the suitability of a short-statured spring triticale as a companion crop and determine optimum triticale seeding rates for grain yield and alfalfa establishment. Spring triticale ‘Trimark 37812’ and alfalfa were grown in companion at Ames and Sioux Center, IA during 2004 and 2005. Triticale was seeded at 198, 297, 396, 495, and 594 pure live seeds (PLS) m−2 and alfalfa was seeded at 600 PLS m−2 The grain yield response to changes in stand density was quadratic with maximum yield occurring at 516 plants m−2 A plant density of 325 plants m−2 and a seeding rate of 374 seeds m−2 resulted in maximum profit. The grain yield at the stand density for maximum profit was 4.4 Mg ha−1 Increasing the triticale seeding rate had no effect on alfalfa stand density or dry matter yield. Alfalfa stand densities exceeded the 130 plants m−2threshold required for maximum long-term productivity suggesting the short-statured spring triticale cultivar used in this study was well suited for companion cropping with alfalfa

Hyperoxic Brain Effects Are Normalized by Addition of CO2

Hyperoxic ventilation leads to responses in brain areas that modify hypothalamus-mediated sympathetic and hormonal outflow; these responses can be diminished by addition of CO2 to the gas mixture

Additional fossil Theropithecus from Hopefield, South Africa: A comparison with other African sites and a reevaluation of its taxonomic status

Additional fossil Theropithecus remains, recovered from mid to late Pleistocene deposits near Hopefield, South Africa, include portions of the jaws of at least five individuals. Extensive comparisons with fossil Theropithecus from other African sites, including Makapan, Swartkrans, Kanjera, Olorgesailie, and Olduvai, reveal few morphological differences, especially when variation in modern gelada baboons ( Theropithecus gelada ) and savannah baboons ( Papio ) is considered. The most pronounced differences between fossil forms are overall size and relative P 3 length. However, these traits do not separate the fossil forms either chronologically or geographically. Other traits, such as depth of the fossa of the mandibular corpus, slope of the upper symphyseal shelf, and variation in the depth of the mandibular corpus, do not distinguish alleged primitive forms (Makapan and lower beds at Olduvai) from remains found at Hopefield, Swartkrans, Kanjera, Olorgesailie, Olduvai Bed IV, or the lower Ndutu Beds. Other traits, such as canine crown height and incisor size, are poorly documented for fossil Theropithecus . Thus, the available evidence suggests that Theropithecus darti and its successional species, T. oswaldi , can best be considered as a single fossil species, T. oswaldi , of which the remains from Hopefield are a late representative. Furthermore, lack of morphological differences dictates that Hopefield Theropithecus not be considered a distinct subspecies. Variation within the Hopefield sample shows that only one taxa is found at this site. Hypothesized physical and climatic conditions at Hopefield during the Pleistocene suggest that T. oswaldi lived near vleis or fresh water lagoons. Comparisons with modern T. gelada suggest a graminivorous diet for the fossil form.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/37626/1/1330630408_ftp.pd

Diffusion maps for changing data

Graph Laplacians and related nonlinear mappings into low dimensional spaces have been shown to be powerful tools for organizing high dimensional data. Here we consider a data set X in which the graph associated with it changes depending on some set of parameters. We analyze this type of data in terms of the diffusion distance and the corresponding diffusion map. As the data changes over the parameter space, the low dimensional embedding changes as well. We give a way to go between these embeddings, and furthermore, map them all into a common space, allowing one to track the evolution of X in its intrinsic geometry. A global diffusion distance is also defined, which gives a measure of the global behavior of the data over the parameter space. Approximation theorems in terms of randomly sampled data are presented, as are potential applications.Comment: 38 pages. 9 figures. To appear in Applied and Computational Harmonic Analysis. v2: Several minor changes beyond just typos. v3: Minor typo corrected, added DO

Formal Alliances, 1816-1965: an Extension of the Basic Data

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/69121/2/10.1177_002234336900600305.pd

Alcohol Abuse/Dependence in Motor Vehicle Crash Victims Presenting to the Emergency Department

Objective: 1) To determine the prevalence of current alcohol abuse/alcohol dependence (AA/AD) among the full injury range of ED motor vehicle crash (MVC) patients; and 2) compare AA/AD and non-AA/AD patient characteristics. Methods: This was a prospective cohort study using a stratified random sample of MVC patients aged ≥18 years presenting to a university hospital and university-affiliated community hospital ED from May 1, 1992, to August 30, 1994. A diagnosis of current AA/AD was based on the alcohol section of the Diagnostic Interview Survey (DIS). Other measurements included the presence of blood alcohol (BAC +), Injury Severity Score (ISS-85), occupant status (driver/passenger), age, gender, seat belt use, culpability for crash, and ED disposition (admitted vs released). A weighted prevalence was determined; subgroups were compared using t-tests, Χ 2 . 2-factor analysis, and logistic regression modeling; Α = 0.05. Results: 1,161 patients were studied. The weighted prevalence of current AA/AD was 22.5%; 53% of these patients were released from the ED. Almost 45% of the patients with current AA/AD were BAC —. When controlling for BAC and AA/AD, greater injury severity and culpability were associated with a BAC +, but not with current AA/AD. Conclusion: Almost 23% of ED MVC patients have current AA/AD; BAC testing does not accurately identify these patients. Intervention strategies must be directed to both admitted and released patients.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73408/1/j.1553-2712.1997.tb03545.x.pd

Trefftz Difference Schemes on Irregular Stencils

The recently developed Flexible Local Approximation MEthod (FLAME) produces accurate difference schemes by replacing the usual Taylor expansion with Trefftz functions -- local solutions of the underlying differential equation. This paper advances and casts in a general form a significant modification of FLAME proposed recently by Pinheiro & Webb: a least-squares fit instead of the exact match of the approximate solution at the stencil nodes. As a consequence of that, FLAME schemes can now be generated on irregular stencils with the number of nodes substantially greater than the number of approximating functions. The accuracy of the method is preserved but its robustness is improved. For demonstration, the paper presents a number of numerical examples in 2D and 3D: electrostatic (magnetostatic) particle interactions, scattering of electromagnetic (acoustic) waves, and wave propagation in a photonic crystal. The examples explore the role of the grid and stencil size, of the number of approximating functions, and of the irregularity of the stencils.Comment: 28 pages, 12 figures; to be published in J Comp Phy

Modern Management of Localized Renal Cell Carcinoma— Is Ablation Part of the Equation?

While the gold-standard for management of localized renal cell carcinoma (RCC) is partial nephrectomy, recent ablative strategies are emerging as alternatives with comparable rates of complications and oncologic outcomes. Thermal ablation, in the form of radiofrequency ablation and cryoablation, is being increasingly accepted by professional societies, and is particularly recommended in patients with a significant comorbidity burden, renal impairment, old age, or in those unwilling to undergo surgery. Maturation of long-term oncologic outcomes has further allowed increased confidence in these management strategies. New and exciting ablation technologies such as microwave ablation, stereotactic body radiotherapy, and irreversible electroporation are emerging. In this article, we review the existing management options for localized RCC, with specific focus on the oncologic outcomes associated with the various ablation modalities