Analyzing spacecraft configurations through specialization and default reasoning

For an intelligent system to describe a real-world situation using as few statements as possible, it is necessary to make inferences based on observed data and to incorporate general knowledge of the reasoning domain into the description. These reasoning processes must reduce several levels of specific descriptions into only those few that most precisely describe the situation. Moreover, the system must be able to generate descriptions in the absence of data, as instructed by certain rules of inference. The deductions applied by the system, then, generate a high-level description from the low-level evidence provided by the real and default data sources. An implementation of these ideas in a real-world situation is described. The application concerns evaluation of Space Shuttle electromechanical system configurations by console operators in the Mission Control Center. A production system provides the reasoning mechanism through which the default assignments and specializations occur. Examples are provided within this domain for each type of inference, and the suitability is discussed of each toward achieving the goal of describing a situation in the fewest statements possible. Finally, several enhancements are suggested that will further increase the intelligence of similar spacecraft monitoring applications

On a production system using default reasoning for pattern classification

This paper addresses an unconventional application of a production system to a problem involving belief specialization. The production system reduces a large quantity of low-level descriptions into just a few higher-level descriptions that encompass the problem space in a more tractable fashion. This classification process utilizes a set of descriptions generated by combining the component hierarchy of a physical system with the semantics of the terminology employed in its operation. The paper describes an application of this process in a program, constructed in C and CLIPS, that classifies signatures of electromechanical system configurations. The program compares two independent classifications, describing the actual and expected system configurations, in order to generate a set of contradictions between the two

Creativity, idea generation, improvisational humor, and product design

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2010.Cataloged from PDF version of thesis.Includes bibliographical references (p. 107-116).It is widely recognized that innovation and creativity is the new competitive battleground for product development firms. Engineers and product designers are now expected to be highly creative, prolific idea generators in addition to being analytically competent. Thus, it is of interest to study methods to improve a designer's idea generation capabilities. It is believed that wit, being spontaneous humor production, is strongly related to creativity as both involve making nonobvious connections between seemingly unrelated things. This thesis looks into the realm of humor and improvisational comedy to suggest means of enhancing creative output in blue-sky product design idea generation. We have found that the ability to quickly generate many ideas is strongly correlated (r2=.82) with being able to come up with a single, promising, creative idea. It was also found that, with appropriate training, individuals may learn to become more prolific idea generators. Furthermore, improvisational comedians were more proficient at new product idea generation than professional product designers, and methods for training comedians can be effectively adapted to product design idea generation. In a study where 84 participants (students, professional designers and improvisational comedians) took a cartoon caption humor test and a nominal product brainstorming test, we found that improvisational comedians on average produced 20% more product ideas and 25% more creative product ideas than professional product designers. Furthermore, the few individuals that were highly prolific in both creative product ideation and humorous cartoon caption production had an improvisational comedy background. Many of the games used in improvisational comedy training are intended to promote associative thinking. We designed an improvisational comedy workshop composed of these association-based games. A group of 11 subjects who participated in this workshop increased their idea output on average by 37% in a subsequent product brainstorming session. Our findings suggest that improvisational comedy games are a useful warm-up for idea generation, that prolific generation is not a domain-specific ability and that it is possible to teach creativity. Ultimately, this work can lead to the development of tools and methods that designers can use to improve their idea generation skills.by Barry Matthew Kudrowitz.Ph.D

Diurnal Variation in Plasma Norepinephrine in Patients with Heart Failure

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/90311/1/phco.19.11.984.31571.pd

Combining active restoration and targeted grazing to establish native plants and reduce fuel loads in invaded ecosystems

Many drylands have been converted from perennial-dominated ecosystems to invaded, annual-dominated, fire-prone systems. Innovative approaches are needed to disrupt fire-invasion feedbacks. Targeted grazing can reduce invasive plant abundance and associated flammable fuels, and fuelbreaks can limit fire spread. Restored strips of native plants (native greenstrips) can function as fuelbreaks while also providing forage and habitat benefits. However, methods for establishing native greenstrips in invaded drylands are poorly developed. Moreover, if fuels reduction and greenstrip establishment are to proceed simultaneously, it is critical to understand how targeted grazing interacts with plant establishment. We determined how targeted grazing treatments interacted with seed rate, spatial planting arrangement (mixtures vs. monoculture strips), seed coating technology, and species identity (five native grasses) to affect standing biomass and seeded plant density in experimental greenstrips. We monitored for two growing seasons to document effects during the seedling establishment phase. Across planting treatments, ungrazed paddocks had the highest second-year seeded plant densities and the highest standing biomass. Paddocks grazed in fall of the second growing season had fewer seedlings than paddocks grazed in spring, five months later. High seed rates minimized negative effects of grazing on plant establishment. Among seeded species, Elymus trachycaulus and Poa secunda had the highest second-year densities, but achieved this via different pathways. Elymus trachycaulus produced the most first-year seedlings, but declined in response to grazing, whereas P. secunda had moderate first-year establishment but high survival across grazing treatments. We identified clear tradeoffs between reducing fuel loads and establishing native plants in invaded sagebrush steppesimilar tradeoffs may exist in other invaded drylands. In our system, tradeoffs were minimized by boosting seed rates, using grazing-tolerant species, and delaying grazing. In invaded ecosystems, combining targeted grazing with high-input restoration may create opportunities to limit wildfire risk while also shifting vegetation toward more desirable species

Simultaneous Broadband Vector Magnetometry Using Solid-State Spins

We demonstrate a vector magnetometer that simultaneously measures all Cartesian components of a dynamic magnetic field using an ensemble of nitrogen-vacancy (NV) centers in a single-crystal diamond. Optical NV-diamond measurements provide high-sensitivity, broadband magnetometry under ambient or extreme physical conditions; and the fixed crystallographic axes inherent to this solid-state system enable vector sensing free from heading errors. In the present device, multi-channel lock-in detection extracts the magnetic-field-dependent spin resonance shifts of NVs oriented along all four tetrahedral diamond axes from the optical signal measured on a single detector. The sensor operates from near DC up to a $12.5$ kHz measurement bandwidth; and simultaneously achieves $\sim\!50$ pT/$\sqrt{\text{Hz}}$ magnetic field sensitivity for each Cartesian component, which is to date the highest demonstrated sensitivity of a full vector magnetometer employing solid-state spins. Compared to optimized devices interrogating the four NV orientations sequentially, the simultaneous vector magnetometer enables a $4\times$ measurement speedup. This technique can be extended to pulsed-type sensing protocols and parallel wide-field magnetic imaging.Comment: 13 pages, 5 figures, 1 table, Supplemental Material included as ancillary fil

The receptor protein tyrosine phosphatase PTPRB negatively regulates FGF2-dependent branching morphogenesis

PTPRB is a transmembrane protein tyrosine phosphatase known to regulate blood vessel remodelling and angiogenesis. Here we demonstrate that PTPRB negatively regulates branching morphogenesis in the mammary epithelium. We show that Ptprb is highly expressed in adult mammary stem cells and also, although at lower levels, in estrogen receptor positive luminal cells. During mammary development Ptprb expression is down-regulated during puberty, a period of extensive of ductal outgrowth and branching. In vivo shRNA knockdown of Ptprb in the cleared mammary fat pad transplant assay resulted in smaller epithelial outgrowths with an increased branching density and also increased branching in an in vitro organoid assay. Organoid branching was dependent on stimulation by FGF2, and Ptprb knockdown in mammary epithelial cells resulted in a higher level of FGFR activation and ERK1/2 phosphorylation, both at baseline and following FGF2 stimulation. Therefore, PTPRB regulates branching morphogenesis in the mammary epithelium by modulating the response of the FGFR signalling pathway to FGF stimulation. Considering the importance of branching morphogenesis in multiple taxa, our findings have general importance outside mammary developmental biology

Residency Exposures and Anticipated Future Involvement in Community Settings

Objective— To assess how exposures to community activities in residency impact anticipated future involvement in community child health settings. Methods— Prospective cohort study of pediatric residents from 10 programs (12 sites) who completed training between 2003 and 2009. Residents reported annual participation for ≥8 days in each of 7 community activities (eg, community settings, child health advocacy) in the prior year. At the start and end of residency, residents reported anticipated involvement in 10 years in 8 community settings (eg, school, shelter). Anticipated involvement was dichotomized: moderate/ substantial (“high”) versus none/limited (“low”). Logistic regression modeled whether residency exposures independently influenced anticipated future involvement at the end of residency. Results— A total of 683 residents completed surveys at the start and end of residency (66.8% participation). More than half of trainees reported ≥8 days’ of involvement in community settings (65.6%) or child health advocacy (53.6%) in residency. Fewer anticipated high involvement in at least 1 community setting at the end of residency than at the start (65.5% vs 85.6%, P < .001). Participation in each community activity mediated but did not moderate relations between anticipated involvement at the start and end of residency. In multivariate models, exposure to community settings in residency was associated with anticipated involvement at end of residency (adjusted odds ratio 1.5; 95% confidence interval 1.2, 2.0). No other residency exposures were associated. Conclusions— Residents who anticipate high involvement in community pediatrics at the start of residency participate in related opportunities in training. Exposure to community settings during residency may encourage community involvement after training