Generating socially appropriate tutorial dialog

Analysis of student-tutor coaching dialogs suggest that good human tutors attend to and attempt to influence the motivational state of learners. Moreover, they are sensitive to the social face of the learner, and seek to mitigate the potential face threat of their comments. This paper describes a dialog generator for pedagogical agents that takes motivation and face threat factors into account. This enables the agent to interact with learners in a socially appropriate fashion, and foster intrinsic motivation on the part of the learner, which in turn may lead to more positive learner affective states

A highly processable metallic glass: Zr41.2Ti13.8Cu12.5Ni10.0Be22.5

We report on the properties of one example of a new family of metallic alloys which exhibit excellent glass forming ability. The critical cooling rate to retain the glassy phase is of the order of 10 K/s or less. Large samples in the form of rods ranging up to 14 mm in diameter have been prepared by casting in silica containers. The undercooled liquid alloy has been studied over a wide range of temperatures between the glass transition temperature and the thermodynamic melting point of the equilibrium crystalline alloy using scanning calorimetry. Crystallization of the material has been studied. Some characteristic properties of the new material are presented. The origins of exceptional glass forming ability of these new alloys are discussed

Effect of Axial Load on the Flexural Properties of an Elastomeric Total Disc Replacement

Study Design. Twelve Cadisc-L devices were subjected to flexion (0°–6°) and extension (0° to -3°) motions at compressive loads between 500 N and 2000 N at a flexural rate between 0.25°/s and 3.0°/s.\ud \ud Objective. To quantify the change in flexural properties of the Cadisc-L (elastomeric device), when subjected to increasing magnitudes of axial load and at different flexural rates.\ud \ud Summary of Background Data. The design of motion preservation devices, used to replace degenerated intervertebral discs, is commonly based on a low-friction, ball-and-socket-articulating joint. Recently, elastomeric implants have been developed that attempt to provide mechanical and motion properties that resemble those of the natural disc more closely.\ud \ud Methods. Twelve Cadisc-L devices (MC-10 mm-9° and MC-10 mm-12° size) were supplied by Ranier Technology Ltd (Cambridge, United Kingdom). The devices were hydrated and tested using a Bose spinal disc-testing machine (Bose Corporation, ElectroForce Systems Group, Eden Prairie, MN) in Ringer's solution at 37°C. A static load of 500 N was applied to a device and it was then subjected to motions of 0° to 6° to 0° (flexion) and 0° to -3° to 0° (extension) at a flexural rate of 0.25°/s, 0.5°/s, 1.0°/s, 1.5°/s, 2.0°/s, and 3.0°/s. Tests were repeated at 1000 N, 1500 N, and 2000 N.\ud \ud Results. Regression analyses showed a significant ($R^2$ > 0.99, $\rho$< 0.05) linear increase in bending moment and flexural stiffness with flexion and extension angles (at 1000 N and higher loads)—a significant ($R^2$> 0.994, $\rho$< 0.05) linear decrease in flexural stiffness in flexion and extension as flexural rate increased.\ud \ud Conclusion. The bending moment of the Cadisc-L increased linearly with flexion and extension angles at 1000 N and higher loads. Flexural stiffness increased with compressive load but decreased with flexural rate.\ud \u

The Volume of some Non-spherical Horizons and the AdS/CFT Correspondence

We calculate the volumes of a large class of Einstein manifolds, namely Sasaki-Einstein manifolds which are the bases of Ricci-flat affine cones described by polynomial embedding relations in C^n. These volumes are important because they allow us to extend and test the AdS/CFT correspondence. We use these volumes to extend the central charge calculation of Gubser (1998) to the generalized conifolds of Gubser, Shatashvili, and Nekrasov (1999). These volumes also allow one to quantize precisely the D-brane flux of the AdS supergravity solution. We end by demonstrating a relationship between the volumes of these Einstein spaces and the number of holomorphic polynomials (which correspond to chiral primary operators in the field theory dual) on the corresponding affine cone.Comment: 25 pp, LaTeX, 1 figure, v2: refs adde

Pricklypear Cactus Control in Western South Dakota

In a range improvement study, both liquid and pelleted forms of Picloram were effective in controlling pricklypear cactus. Higher rates of chemical hastened control and gave more complete control. At lower rates, cactus was recovering in 1985, the fourth year of study, suggesting that higher rates may be most cost effective. In 1983 noncactus vegetation response was minor. In 1984, all perennial grass production increased by more than 50% (312 lb/A) at higher rates of Picloram. Shifts in cool season and “warm season grass components were nonsignificant. In 1985, cool season grass was not generally affected by treatments, but warm season grass increased at several rates of Picloram. Cactus continued to decrease. Grass utilization by cattle in 1984 increased greatly at higher rates of Picloram. It appears likely that desirable grazable forage can be increased when cactus is decreased. Access to forage appears t o improve substantially as cactus pads collapse. Based only on 1984 livestock grazing utilization estimates and on 1984 increases in perennial grass production, potential reductions in acreages required for livestock grazing ranged from 49 t o 72%. Economic analyses will be conducted a t the end of the study

A system for phenotype harmonization in the National Heart, Lung, and Blood Institute Trans-Omics for Precision Medicine (TOPMed) program

Genotype-phenotype association studies often combine phenotype data from multiple studies to increase statistical power. Harmonization of the data usually requires substantial effort due to heterogeneity in phenotype definitions, study design, data collection procedures, and data-set organization. Here we describe a centralized system for phenotype harmonization that includes input from phenotype domain and study experts, quality control, documentation, reproducible results, and data-sharing mechanisms. This system was developed for the National Heart, Lung, and Blood Institute’s Trans-Omics for Precision Medicine (TOPMed) program, which is generating genomic and other -omics data for more than 80 studies with extensive phenotype data. To date, 63 phenotypes have been harmonized across thousands of participants (recruited in 1948–2012) from up to 17 studies per phenotype. Here we discuss challenges in this undertaking and how they were addressed. The harmonized phenotype data and associated documentation have been submitted to National Institutes of Health data repositories for controlled access by the scientific community. We also provide materials to facilitate future harmonization efforts by the community, which include 1) the software code used to generate the 63 harmonized phenotypes, enabling others to reproduce, modify, or extend these harmonizations to additional studies, and 2) the results of labeling thousands of phenotype variables with controlled vocabulary terms.Peer ReviewedPostprint (published version

A new type of carbon resistance thermometer with excellent thermal contact at millikelvin temperatures

Using a new brand of commercially available carbon resistor we built a cryogenic thermometer with an extremely good thermal contact to its thermal environment. Because of its superior thermal contact the thermometer is insensitive to low levels of spurious radio frequency heating. We calibrated our thermometer down to 5mK using a quartz tuning fork He-3 viscometer and measured its thermal resistance and thermal response time.Comment: 5 pages, 4 figure

An Epidemiologic Study of Dental Caries in Preschool Children in the United States by Race and Socioeconomic Level

The prevalence of dental caries in 1,155 white and black preschool children was studied in the United States in 1969 and 1970. The results demonstrated that white children of the lower socioeconomic level had a significantly greater prevalence of dental caries than middle class white children, but a significantly lower prevalence than black children, most of whom represented the lower social class.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/67244/2/10.1177_00220345740530023501.pd

Tank Applied Testing of Load-Bearing Multilayer Insulation (LB-MLI)

The development of long duration orbital cryogenic storage systems will require the reduction of heat loads into the storage tank. In the case of liquid hydrogen, complete elimination of the heat load at 20 K is currently impractical due to the limitations in lift available on flight cryocoolers. In order to reduce the heat load, without having to remove heat at 20 K, the concept of Reduced Boil-Off uses cooled shields within the insulation system at approximately 90 K. The development of Load-Bearing Multilayer Insulation (LB-MLI) allowed the 90 K shield with tubing and cryocooler attachments to be suspended within the MLI and still be structurally stable. Coupon testing both thermally and structurally were performed to verify that the LB-MLI should work at the tank applied level. Then tank applied thermal and structural (acoustic) testing was performed to demonstrate the functionality of the LB-MLI as a structural insulation system. The LB-MLI showed no degradation of thermal performance due to the acoustic testing and showed excellent thermal performance when integrated with a 90 K class cryocooler on a liquid hydrogen tank