1,243 research outputs found
Honorius Augustodunensis, Exposition of Selected Psalms
The abbreviated Psalms commentary by Honorius Augustodunensis (ca. 1070 – ca. 1140)—a redaction of his own, much larger commentary on the entire Psalter—participates in a long tradition of Christian interpretation of the Book of Psalms. A prolific author closely associated with Anselm of Canterbury, Rupert of Deutz, and Gilbert of Poitiers, Honorius wrote a massive commentary on the Psalms when the so-called “school of Laon” was at work on the Glossa ordinaria. Honorius’s work shares the academic interest of that school, while simultaneously serving the devotion of the Benedictine Reform. His Exposition of Selected Psalms highlights a tripartite division of the Psalter, even as it discovers in the psalms an apocalypticism fitting to the Church in its last age.https://scholarworks.wmich.edu/mip_teamscs/1013/thumbnail.jp
Solid friction between soft filaments
Any macroscopic deformation of a filamentous bundle is necessarily
accompanied by local sliding and/or stretching of the constituent filaments.
Yet the nature of the sliding friction between two aligned filaments
interacting through multiple contacts remains largely unexplored. Here, by
directly measuring the sliding forces between two bundled F-actin filaments, we
show that these frictional forces are unexpectedly large, scale logarithmically
with sliding velocity as in solid-like friction, and exhibit complex dependence
on the filaments' overlap length. We also show that a reduction of the
frictional force by orders of magnitude, associated with a transition from
solid-like friction to Stokes' drag, can be induced by coating F-actin with
polymeric brushes. Furthermore, we observe similar transitions in filamentous
microtubules and bacterial flagella. Our findings demonstrate how altering a
filament's elasticity, structure and interactions can be used to engineer
interfilament friction and thus tune the properties of fibrous composite
materials
Advances in Salish Sea Acoustic Telemetry: 2015 Array Deployments and Promising Transmitter Performance
The first fish tracking arrays were deployed in the Salish Sea over a decade ago. These arrays have yielded a rich data set which have provided the first direct estimates of early marine-survival and migratory behavior for acoustic-tagged juvenile sockeye, Chinook, Coho and steelhead \u3e130 mm in fork length (FL). In spring of 2015, as part of the Salish Sea Marine Survival Project, the Pacific Salmon Foundation, the Ocean Tracking Network and Kintama Research deployed additional arrays in the Discovery Islands and Johnstone Strait (north of the Strait of Georgia) to provide higher resolution survival data. These new arrays use receivers that can detect VEMCO acoustic tags that transmit at 69 kHz, as well as new, smaller tags that transmit at 180 kHz. These new tags can be implanted into smaller salmon smolts (\u3e100 mm FL), but the disadvantage is reduced detection range and battery life. When designing the array, we considered the tradeoffs between detection efficiency, survival estimation, array design, and costs, and then tested the performance of the smaller tag by double-tagging 50 steelhead smolts with both tag types. We used high powered 69 kHz V9 tags to estimate presence because these tags have had excellent detection efficiency in past studies. The smaller 180 kHz V4 tag programming emulated the programming typically used to track small salmon smolts through the SOG. To estimate the detection efficiency of the smaller tag, we compared the number of 180 kHz ID codes to the number of 69 kHz ID codes detected on each array. The resulting detection efficiency of the V4 tag on the Discovery Islands sub-array was 74% (SE=0.10). Thus for the many salmon populations that migrate north through the Salish Sea (e.g. many Fraser River populations), it is now possible to estimate early-marine survival over a wider range of smolts sizes
ACTS 118x Final Report High-Speed TCP Interoperability Testing
With the recent explosion of the Internet and the enormous business opportunities available to communication system providers, great interest has developed in improving the efficiency of data transfer using the Transmission Control Protocol (TCP) of the Internet Protocol (IP) suite. The satellite system providers are interested in solving TCP efficiency problems associated with long delas and error-prone links. Similarly, the terrestrial community is interested in solving TCP problems over high-bandwidth links. Whereas the wireless community is intested in improving TCP performance over bandwidth constrained, error-prone links.
NASA realized that solutions had already been proposed for most of the problems associated with efficient data transfer over large bandwidth-delay links (which include satellite links). The solutions are detailed in various Internet Engineering Task Force (IETF) Request for Comments (RFCs). Unfortunately, most of these solutions had not been tested at high-speed (155+ Mbps). Therefore, the NASA\u27s ACTS experiments program initiated a series of TCP experiments to demonstrate scalability of TCP/IP and determine how far the protocol can be optimised over a 622 Mbps satellite link. These experiments were known as the 118i and 118j experiments.
During the 118i and 118j experiments, NASA worled closely with SUN Microsystems and FORE Systems to improve the operating system, TCP stacks, and network interface cards and drivers. We were able to obtain instantaneous data througput rates of greater than 529 Mbps and average throughput rates of 470 Mbps using TCP over Asynchronous Transfer Mode (ATM) over a 622 Mbps Synchronous Optical Network (SONET) OC12 link. Following the success of these experiments and the successful government/industry collaboration, a new series of experiments, the 118x experiments, were developed
Spatio-Temporal Migration Patterns of Pacific Salmon Smolts in Rivers and Coastal Marine Waters
BACKGROUND: Migrations allow animals to find food resources, rearing habitats, or mates, but often impose considerable predation risk. Several behavioural strategies may reduce this risk, including faster travel speed and taking routes with shorter total distance. Descriptions of the natural range of variation in migration strategies among individuals and populations is necessary before the ecological consequences of such variation can be established. METHODOLOGY/PRINCIPAL FINDINGS: Movements of tagged juvenile coho, steelhead, sockeye, and Chinook salmon were quantified using a large-scale acoustic tracking array in southern British Columbia, Canada. Smolts from 13 watersheds (49 watershed/species/year combinations) were tagged between 2004-2008 and combined into a mixed-effects model analysis of travel speed. During the downstream migration, steelhead were slower on average than other species, possibly related to freshwater residualization. During the migration through the Strait of Georgia, coho were slower than steelhead and sockeye, likely related to some degree of inshore summer residency. Hatchery-reared smolts were slower than wild smolts during the downstream migration, but after ocean entry, average speeds were similar. In small rivers, downstream travel speed increased with body length, but in the larger Fraser River and during the coastal migration, average speed was independent of body length. Smolts leaving rivers located towards the northern end of the Strait of Georgia ecosystem migrated strictly northwards after ocean entry, but those from rivers towards the southern end displayed split-route migration patterns within populations, with some moving southward. CONCLUSIONS/SIGNIFICANCE: Our results reveal a tremendous diversity of behavioural migration strategies used by juvenile salmon, across species, rearing histories, and habitats, as well as within individual populations. During the downstream migration, factors that had strong effects on travel speeds included species, wild or hatchery-rearing history, watershed size and, in smaller rivers, body length. During the coastal migration, travel speeds were only strongly affected by species differences
Program Assessment the Easy Way: Using Embedded Indicators to Assess Program Outcomes
The culminating design experience for civil engineering majors at the United States Military Academy (USMA) is CE492, Design of Structural Systems. CE492 serves as a “capstone” experience or one in which students are faced with a multi-disciplinary design project incorporating facets from all previous civil engineering courses. Previous capstone experiences have required students to design structures planned for construction or currently under construction at the Academy, thus providing an opportunity for site visitations and active participation with key players in the project development process. Since CE492 provides a multi-disciplinary experience, it also provides an ideal opportunity for the application of embedded assessment indicators. The purpose of this paper is to describe the use of an embedded assessment technique which has been used successfully for two semesters in CE450, Infrastructure Development and Construction Management, to assess accomplishment of the Academy’s Engineering and Technology Goal. By merging the student evaluation and assessment processes in CE492, instructor workload was reduced, student evaluation was tied more closely to the relevant academic program and the ASCE Body of Knowledge (BOK) outcomes, and a systematic method was created for identifying shortcomings and areas of excellence in the program
Rotifers as experimental tools for investigating aging
© 2014 The Author(s). This is an Open Access article. The definitive version was published in Invertebrate Reproduction & Development 59, Supple. 1 (2015): 5-10, doi:10.1080/07924259.2014.925516.Comparative biogerontology has much to contribute to the study of aging. A broad range of aging rates have evolved to meet environmental challenges, and understanding these adaptations can produce valuable insights into aging. The supra Phylum Lophotrochozoa is particularly understudied and has several groups that have intriguing patterns of aging. Members of the Lophotrochozoan phylum Rotifera are particularly useful for aging studies because cohort life tables can be conducted with them easily, and biochemical and genomic tools are available for examining aging mechanisms. This paper reviews a variety of caloric restriction (CR) regimens, small molecule inhibitors, and dietary supplements that extend rotifer lifespan, as well as important interactions between CR and genotype, antioxidant supplements, and TOR and jun-N-terminal kinase (JNK) pathways, and the use of RNAi to identify key genes involved in modulating the aging response. Examples of how rapamycin and JNK inhibitor exposure keeps mortality rates low during the reproductive phase of the life cycle are presented, and the ease of conducting life table experiments to screen natural products from red algae for life extending effects is illustrated. Finally, experimental evolution to produce longer-lived rotifer individuals is demonstrated, and future directions to determine the genetic basis of aging are discussed.We are grateful for the support of the National Institute of
Aging, [grant number R01 AG037960-02] for this work and
for a Postdoctoral Fellowship from the Ellison Medical Foundation/
American Federation for Aging Research to K. Gribble
Efficiency of spinal anesthesia versus general anesthesia for lumbar spinal surgery: a retrospective analysis of 544 patients.
BACKGROUND: Previous studies have shown varying results in selected outcomes when directly comparing spinal anesthesia to general in lumbar surgery. Some studies have shown reduced surgical time, postoperative pain, time in the postanesthesia care unit (PACU), incidence of urinary retention, postoperative nausea, and more favorable cost-effectiveness with spinal anesthesia. Despite these results, the current literature has also shown contradictory results in between-group comparisons.
MATERIALS AND METHODS: A retrospective analysis was performed by querying the electronic medical record database for surgeries performed by a single surgeon between 2007 and 2011 using procedural codes 63030 for diskectomy and 63047 for laminectomy: 544 lumbar laminectomy and diskectomy surgeries were identified, with 183 undergoing general anesthesia and 361 undergoing spinal anesthesia (SA). Linear and multivariate regression analyses were performed to identify differences in blood loss, operative time, time from entering the operating room (OR) until incision, time from bandage placement to exiting the OR, total anesthesia time, PACU time, and total hospital stay. Secondary outcomes of interest included incidence of postoperative spinal hematoma and death, incidence of paraparesis, plegia, post-dural puncture headache, and paresthesia, among the SA patients.
RESULTS: SA was associated with significantly lower operative time, blood loss, total anesthesia time, time from entering the OR until incision, time from bandage placement until exiting the OR, and total duration of hospital stay, but a longer stay in the PACU. The SA group experienced one spinal hematoma, which was evacuated without any long-term neurological deficits, and neither group experienced a death. The SA group had no episodes of paraparesis or plegia, post-dural puncture headaches, or episodes of persistent postoperative paresthesia or weakness.
CONCLUSION: SA is effective for use in patients undergoing elective lumbar laminectomy and/or diskectomy spinal surgery, and was shown to be the more expedient anesthetic choice in the perioperative setting
A Kalman Approach to Lunar Surface Navigation using Radiometric and Inertial Measurements
Future lunar missions supporting the NASA Vision for Space Exploration will rely on a surface navigation system to determine astronaut position, guide exploration, and return safely to the lunar habitat. In this report, we investigate one potential architecture for surface navigation, using an extended Kalman filter to integrate radiometric and inertial measurements. We present a possible infrastructure to support this technique, and we examine an approach to simulating navigational accuracy based on several different system configurations. The results show that position error can be reduced to 1 m after 5 min of processing, given two satellites, one surface communication terminal, and knowledge of the starting position to within 100 m
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