1,440 research outputs found

    ROBOSIM, a simulator for robotic systems

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    ROBOSIM, a simulator for robotic systems, was developed by NASA to aid in the rapid prototyping of automation. ROBOSIM has allowed the development of improved robotic systems concepts for both earth-based and proposed on-orbit applications while significantly reducing development costs. In a cooperative effort with an area university, ROBOSIM was further developed for use in the classroom as a safe and cost-effective way of allowing students to study robotic systems. Students have used ROBOSIM to study existing robotic systems and systems which they have designed in the classroom. Since an advanced simulator/trainer of this type is beneficial not only to NASA projects and programs but industry and academia as well, NASA is in the process of developing this technology for wider public use. An update on the simulators's new application areas, the improvements made to the simulator's design, and current efforts to ensure the timely transfer of this technology are presented

    Evolutionary plasticity of developmental gene regulatory network architecture

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    Sea stars and sea urchins evolved from a last common ancestor that lived at the end of the Cambrian, approximately half a billion years ago. In a previous comparative study of the gene regulatory networks (GRNs) that embody the genomic program for embryogenesis in these animals, we discovered an almost perfectly conserved five-gene network subcircuit required for endoderm specification. We show here that the GRN structure upstream and downstream of the conserved network kernel has, by contrast, diverged extensively. Mesoderm specification is accomplished quite differently; the Delta–Notch signaling system is used in radically distinct ways; and various regulatory genes have been coopted to different functions. The conservation of the conserved kernel is thus the more remarkable. The results indicate types of network linkage subject to evolutionary change. An emergent theme is that subcircuit design may be preserved even while the identity of genes performing given roles changes because of alteration in their cis-regulatory control systems

    Midwestern Geology and Cornell College: The First 125 Years

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    The history of geology at Cornell College can be traced back almost to the college\u27s beginnings. Though not the first to reach geology at Cornell, William Harmon Norton, more than any other person, shaped the Department of Geology and set it on its course of excellence. Born in 1856, the son of a Methodist minister, Norton developed an ardent interest in geology in his boyhood. A graduate of Cornell in Classics, Norton was hired by his alma mater in 1876 to reach Greek, bur his avocation was geology. He spent most of his spare time on weekends and during summers studying the rocks and fossils of eastern Iowa. Norton\u27s avocation became his vocation in 1881 when he began reaching geology along with Greek. Nine years later he gave up classics and continued with geology. His skills as a keen observer, mapper, and writer were recognized by Samuel Calvin, director of the new Iowa Geological Survey, and he was hired in 1893 under the ride Special Geology\u27\u27. Norton authored several publications on the geology of eastern Iowa, including reports on the geology of Linn, Scott, Cedar and Bremer Countries. During the course of his research he recognized and described several new Silurian and Devonian formations, the names of which are currently in use. He is best known for his studies on the character and distribution of Iowa\u27s underground water resources, with publications totaling nearly 2,000 pages. His service to the Iowa Geological Survey spanned 40 years and his tenure as a teacher at Cornell 67 years. Norton\u27s legacy includes a college textbook, Elements of Geology , written in collaboration with William Morris Davis, and 6,000 lantern slides

    Prescribed Fire Monitoring Report, Tallgrass Prairie National Preserve 2014 (IQCS fire number 285382, 285383, 266782, 285677)

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    Introduction In 2014, the preserve’s federal and NGO partners conducted prescribed fires during March, April, and October that encompassed 8129.8 acres of Tallgrass Prairie National Preserve (TAPR). This was a unique burn year in that prescribed burns occurred in the spring, the traditional burn season, and the fall. Fall burns were conducted to support needed archaeological surveys as part of the environmental compliance for a symphony event scheduled for June 2015 at the preserve. Burns at TAPR were coordinated with local US Fish and Wildlife Service (USFWS), The Nature Conservancy (TNC), and various units of the National Park Service. Burns conducted in spring 2014 included: Red House Pasture, Crusher Hill Pasture, the southwest portion of Windmill Pasture, Big Pasture-North, Two Section, East Traps, and Bottomland Restorations (Fields 4, 8, and 18, and the east half of Field 20). In fall 2014, they included: the northeast portion of Windmill Pasture, Big Pasture-South, Southwind Nature Trail/Headquarters, and the northeast portion of Red House Pasture. These areas were successfully burned over the course of three days in the spring and two days in the fall (Table 1; See figure 8 for map of all burned areas.). The fire ecologist was unable to participate in the spring burn events, but was onsite for one day of fall burning. This report presents the 2014 monitoring data in the context of available long-term data that has been collected at TAPR since 2010

    Spatial and temporal structure of typhoid outbreaks in Washington, D.C., 1906–1909: evaluating local clustering with the G(i)* statistic

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    BACKGROUND: To better understand the distribution of typhoid outbreaks in Washington, D.C., the U.S. Public Health Service (PHS) conducted four investigations of typhoid fever. These studies included maps of cases reported between 1 May – 31 October 1906 – 1909. These data were entered into a GIS database and analyzed using Ripley's K-function followed by the G(i)* statistic in yearly intervals to evaluate spatial clustering, the scale of clustering, and the temporal stability of these clusters. RESULTS: The Ripley's K-function indicated no global spatial autocorrelation. The G(i)* statistic indicated clustering of typhoid at multiple scales across the four year time period, refuting the conclusions drawn in all four PHS reports concerning the distribution of cases. While the PHS reports suggested an even distribution of the disease, this study quantified both areas of localized disease clustering, as well as mobile larger regions of clustering. Thus, indicating both highly localized and periodic generalized sources of infection within the city. CONCLUSION: The methodology applied in this study was useful for evaluating the spatial distribution and annual-level temporal patterns of typhoid outbreaks in Washington, D.C. from 1906 to 1909. While advanced spatial analyses of historical data sets must be interpreted with caution, this study does suggest that there is utility in these types of analyses and that they provide new insights into the urban patterns of typhoid outbreaks during the early part of the twentieth century

    A study of the use of banks as an alternative delivery system for real estate brokerage services

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    Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Architecture, 1988.Includes bibliographical references (leaves 90-91).by Larry E. Hinman.M.S

    Influences of lithology on water quality: a study of the Ngam and Mou watersheds in West Cameroon (Central Africa)

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    The Ngam and Mou Rivers belong to the river system of the central part of the Cameroon Volcanic Line. The Ngam River watershed comprises 51 Ma old basalts, while the Mou River watershed comprises younger, \u3c 5 Ma pyroclastic basalts. The physico-chemical characteristics of water samples from both watersheds indicated pH between 4.2 and 8.2, and 4.2 to 7.5, and very low mineralization between 11 and 246 μS/cm and 45 to 165 μS/cm, respectively, for the Ngam River and the Mou River. Chemical data showed that waters from old, highly weathered plateau basalts (Ngam River watershed) were dominated by calcium and sodium (signatures of feldpars from syenites and orthogneisses), while waters in the Mou River watershed were dominated by magnesium (signature of olivines and pyroxenes from basalts). Mineralizations in the two watersheds are thus primarily controlled by lithology rather than anthropic activities. These results are promising for identifying potential potable water resources in these areas

    Pharmacological and Physiological Characterization of the Tremulous Jaw Movement Model of Parkinsonian Tremor: Potential Insights into the Pathophysiology of Tremor

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    Tremor is a cardinal symptom of parkinsonism, occurring early on in the disease course and affecting more than 70% of patients. Parkinsonian resting tremor occurs in a frequency range of 3–7 Hz and can be resistant to available pharmacotherapy. Despite its prevalence, and the significant decrease in quality of life associated with it, the pathophysiology of parkinsonian tremor is poorly understood. The tremulous jaw movement (TJM) model is an extensively validated rodent model of tremor. TJMs are induced by conditions that also lead to parkinsonism in humans (i.e., striatal DA depletion, DA antagonism, and cholinomimetic activity) and reversed by several antiparkinsonian drugs (i.e., DA precursors, DA agonists, anticholinergics, and adenosine A2A antagonists). TJMs occur in the same 3–7 Hz frequency range seen in parkinsonian resting tremor, a range distinct from that of dyskinesia (1–2 Hz), and postural tremor (8–14 Hz). Overall, these drug-induced TJMs share many characteristics with human parkinsonian tremor, but do not closely resemble tardive dyskinesia. The current review discusses recent advances in the validation of the TJM model, and illustrates how this model is being used to develop novel therapeutic strategies, both surgical and pharmacological, for the treatment of parkinsonian resting tremor

    RNA deep sequencing reveals differential MicroRNA expression during development of sea urchin and sea star

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    microRNAs (miRNAs) are small (20-23 nt), non-coding single stranded RNA molecules that act as post-transcriptional regulators of mRNA gene expression. They have been implicated in regulation of developmental processes in diverse organisms. The echinoderms, Strongylocentrotus purpuratus (sea urchin) and Patiria miniata (sea star) are excellent model organisms for studying development with well-characterized transcriptional networks. However, to date, nothing is known about the role of miRNAs during development in these organisms, except that the genes that are involved in the miRNA biogenesis pathway are expressed during their developmental stages. In this paper, we used Illumina Genome Analyzer (Illumina, Inc.) to sequence small RNA libraries in mixed stage population of embryos from one to three days after fertilization of sea urchin and sea star (total of 22,670,000 reads). Analysis of these data revealed the miRNA populations in these two species. We found that 47 and 38 known miRNAs are expressed in sea urchin and sea star, respectively, during early development (32 in common). We also found 13 potentially novel miRNAs in the sea urchin embryonic library. miRNA expression is generally conserved between the two species during development, but 7 miRNAs are highly expressed in only one species. We expect that our two datasets will be a valuable resource for everyone working in the field of developmental biology and the regulatory networks that affect it. The computational pipeline to analyze Illumina reads is available at http://www.benoslab.pitt.edu/services.html. © 2011 Kadri et al
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