1,217 research outputs found

    Space and biotechnology: An industry profile

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    The results of a study conducted by the Center for Space and Advanced Technology (CSAT) for NASA-JSC are presented. The objectives were to determine the interests and attitudes of the U.S. biotechnology industry toward space biotechnology and to prepare a concise review of the current activities of the biotechnology industry. In order to accomplish these objectives, two primary actions were taken. First, a questionnaire was designed, reviewed, and distributed to U.S. biotechnology companies. Second, reviews of the various biotechnology fields were prepared in several aspects of the industry. For each review, leading figures in the field were asked to prepare a brief review pointing out key trends and current industry technical problems. The result is a readable narrative of the biotechnology industry which will provide space scientists and engineers valuable clues as to where the space environment can be explored to advance the U.S. biotechnology industry

    Representation in Westminster in the 1990s : The ghost of Edmund Burke

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    Why are 'trustee' notions of representation still invoked in the UK House of Commons in the 1990s? In answering this question this article analyses the premises of Burkean theory and the arguments that these premises are of little relevance in the late twentieth century. Despite these dismissals of trusteeship, Burkean ideas are still articulated in the Commons some 200 years after they were first voiced. The idea of trusteeship can prove extremely useful to justify the actions of representatives when those actions conflict with constituency 'opinion', party policy or the wishes of interest groups. Examples of the occasions when Burkean notions have been invoked in the 1990s are provided

    Theme Schools: From Manifesto to Paradigm for Undergraduate Students

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    In sciences, when anomalies or discrepant observations generate a crisis, so that the old way of looking at things no longer suffices to explain or predict observable events, scientists construct a new paradigm (Kuhn, 1996). Despite vast differences in our backgrounds and in the attributes of our widely separated home institutions, we have arrived at strikingly similar perceptions of the need to fashion a new paradigm within undergraduate education. By aligning the anomalies and assembling experiences from several correlative efforts within the old paradigm, we have begun to distill some tenets of a coherent rationale for student-centred learning, built around the concepts inherent in a "theme school." These tenets are especially relevant to small, widely dispersed northern communities. Much of the following discussion originates in our shared disappointments with the effectiveness of education by the traditional Euro-American undergraduate paradigm when applied to northern environments and rural communities. Nevertheless, we are not institution-bashing: we owe much, after all, to the institutions that provided us with a point of departure for exploring alternatives and supplements

    Functional correlates of optic flow motion processing in Parkinson’s disease

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    The visual input created by the relative motion between an individual and the environment, also called optic flow, influences the sense of self-motion, postural orientation, veering of gait, and visuospatial cognition. An optic flow network comprising visual motion areas V6, V3A, and MT+, as well as visuo-vestibular areas including posterior insula vestibular cortex (PIVC) and cingulate sulcus visual area (CSv), has been described as uniquely selective for parsing egomotion depth cues in humans. Individuals with Parkinson’s disease (PD) have known behavioral deficits in optic flow perception and visuospatial cognition compared to age- and education-matched control adults (MC). The present study used functional magnetic resonance imaging (fMRI) to investigate neural correlates related to impaired optic flow perception in PD. We conducted fMRI on 40 non-demented participants (23 PD and 17 MC) during passive viewing of simulated optic flow motion and random motion. We hypothesized that compared to the MC group, PD participants would show abnormal neural activity in regions comprising this optic flow network. MC participants showed robust activation across all regions in the optic flow network, consistent with studies in young adults, suggesting intact optic flow perception at the neural level in healthy aging. PD participants showed diminished activity compared to MC particularly within visual motion area MT+ and the visuo-vestibular region CSv. Further, activation in visuo-vestibular region CSv was associated with disease severity. These findings suggest that behavioral reports of impaired optic flow perception and visuospatial performance may be a result of impaired neural processing within visual motion and visuo-vestibular regions in PD.Published versio

    Intra-Oral Colonization of Macaque Monkeys by Actinobacillus Actinomycetemcomitans

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    Actinobacillus actinomycetemcomitans was acquired by captive Macaca fascicularis 3 to 6 months after birth, and all monkeys aged over 6 months harbored detectable levels. This microorganism was most frequently isolated from the gingival plaque of the incisor (and other) teeth compared with other oral sites. Strains were leukotoxic by bioassay and Western blot analysis. Antibodies in macaque serum contained neutralized the leukotoxin of a human A. actinomycetemcomitans strain. High titres of maternal neutralizing anti-leukotoxin antibodies were detected in neonates; the titre then fell rapidly so that by 6 months the antibody titer was zero. Antileukotoxin antibody production was detected after 6 months of age, rapidly reaching a high level within 2 years after birth. The presence of leukotoxic strains of A. actinomycetemcomitans in the gingival region did not appear to be correlated with an increase in susceptibility to periodontal disease

    Deciphering the Pre–solar-storm Features of the 2017 September Storm From Global and Local Dynamics

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    We investigate whether global toroid patterns and the local magnetic field topology of solar active region (AR) 12673 together can hindcast the occurrence of the biggest X-flares of solar cycle (SC)-24. Magnetic toroid patterns (narrow latitude belts warped in longitude, in which ARs are tightly bound) derived from the surface distributions of ARs, prior and during AR 12673 emergence, reveal that the portions of the south toroid containing AR 12673 was not tipped away from its north-toroid counterpart at that longitude, unlike the 2003 Halloween storms scenario. During the minimum phase there were too few emergences to determine multimode longitudinal toroid patterns. A new emergence within AR 12673 produced a complex nonpotential structure, which led to the rapid buildup of helicity and winding that triggered the biggest X-flare of SC-24, suggesting that this minimum-phase storm can be anticipated several hours before its occurrence. However, global patterns and local dynamics for a peak-phase storm, such as that from AR 11263, behaved like the 2003 Halloween storms, producing the third biggest X-flare of SC-24. AR 11263 was present at the longitude where the north and south toroids tipped away from each other. While global toroid patterns indicate that prestorm features can be forecast with a lead time of a few months, their application to observational data can be complicated by complex interactions with turbulent flows. Complex nonpotential field structure development hours before the storm are necessary for short-term prediction. We infer that minimum-phase storms cannot be forecast accurately more than a few hours ahead, while flare-prone ARs in the peak phase may be anticipated much earlier, possibly months ahead from global toroid patterns
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