Ribosomal trafficking is reduced in Schwann cells following induction of myelination.

Local synthesis of proteins within the Schwann cell periphery is extremely important for efficient process extension and myelination, when cells undergo dramatic changes in polarity and geometry. Still, it is unclear how ribosomal distributions are developed and maintained within Schwann cell projections to sustain local translation. In this multi-disciplinary study, we expressed a plasmid encoding a fluorescently labeled ribosomal subunit (L4-GFP) in cultured primary rat Schwann cells. This enabled the generation of high-resolution, quantitative data on ribosomal distributions and trafficking dynamics within Schwann cells during early stages of myelination, induced by ascorbic acid treatment. Ribosomes were distributed throughout Schwann cell projections, with ~2-3 bright clusters along each projection. Clusters emerged within 1 day of culture and were maintained throughout early stages of myelination. Three days after induction of myelination, net ribosomal movement remained anterograde (directed away from the Schwann cell body), but ribosomal velocity decreased to about half the levels of the untreated group. Statistical and modeling analysis provided additional insight into key factors underlying ribosomal trafficking. Multiple regression analysis indicated that net transport at early time points was dependent on anterograde velocity, but shifted to dependence on anterograde duration at later time points. A simple, data-driven rate kinetics model suggested that the observed decrease in net ribosomal movement was primarily dictated by an increased conversion of anterograde particles to stationary particles, rather than changes in other directional parameters. These results reveal the strength of a combined experimental and theoretical approach in examining protein localization and transport, and provide evidence of an early establishment of ribosomal populations within Schwann cell projections with a reduction in trafficking following initiation of myelination

Cotton spinning to climbing gear: practical aspects of design evolution in Lancashire and the North West of England

This article looks at the role of path dependency in the design of outdoor clothing and equipment, from the perspective of changing and overlapping industrial clusters in Lancashire and Sheffield, from the 1960s. It demonstrates that, unlike the fashion market, design in mountaineering clothing and equipment was originally based heavily upon functionality and hence on user innovation. It shows that skills and knowledge which evolved during the industrial revolution, in both industrial areas, were vitally important to the development of internationally competitive mountaineering equipment firms. It was, however, the way in which these sources of knowledge were combined with sporting expertise that contributed to the design of innovative functional products. In addition, fundamental changes occurred in the relationship between manufacturers and their customers and these were vital to the success of this process, marking a departure from past practice

High altitude gust acceleration environment as experienced by a supersonic airplane

High altitude turbulence experienced at supersonic speeds is described in terms of gust accelerations measured on the YF-12A airplane. The data were obtained during 90 flights at altitudes above 12.2 kilometers (40,000 feet). Subjective turbulence intensity ratings were obtained from air crew members. The air crew often rated given gust accelerations as being more intense during high altitude supersonic flight than during low altitude subsonic flight. The portion of flight distance in turbulence ranged from 6 percent to 8 percent at altitudes between 12.2 kilometers and 16.8 kilometers (40,000 feet and 55,000 feet) to less than 1 percent at altitudes above 18.3 kilometers (60,000 feet). The amount of turbulence varied with season, increasing by a factor of 3 or more from summer to winter. Given values of gust acceleration were less frequent, on the basis of distance traveled, for supersonic flight of the YF-12A airplane at altitudes above 12.2 kilometers (40,000 feet) than for subsonic flight of a jet passenger airplane at altitudes below 12.2 kilometers (40,000 feet). The median thickness of high altitude turbulence patches was less than 400 meters (1300 feet); the median length was less than 16 kilometers (10 miles). The distribution of the patch dimensions tended to be log normal

The Petrographic Analysis of Sherds from the Musgano Site (41RK19), Rusk County, Texas

Characterizing the mineralogical composition of ceramic vessels and sherds from Caddo sites in East Texas by means of petrographic analysis provides a unique opportunity to gather and investigate empirical evidence from ceramic vessels on: (1) technological and manufacturing practices, and (2) their trade and exchange at varying scales conducted by ancestral Caddo people with their neighbors, both near and far (i.e., other ancestral Caddo groups as well as non-Caddo communities). This evidence in turn can be used to explore changes in the nature of social and economic relationships between particular Caddo groups and other prehistoric populations. Identified compositional and paste differences that have been recognized between the different wares made by Caddo groups (i.e., plain wares, utility wares, and fine wares) can also be employed to explore functional and technological differences in vessel function and form. It is important to build on existing petrographic studies of Caddo vessels and vessel sherds by examining unstudied assemblages to (1) better clarify the compositional nature of these ceramic wares across the Caddo temporal and geographic landscape; (2) to help pinpoint other ceramic manufacturing locales and mineralogical compositional groups, but also to assess their apparent technological complexity; and (3) lead to better evaluations of the regional character of prehistoric and historic Caddo trade and interaction networks that existed, and more definitively establish whether there were changes through time in the direction and intensity of local and long distance trade and interaction. The disparate pieces of information contained within the sherds and vessel fragments of Caddo ceramics found on many prehistoric and early historic sites throughout the region have the potential to address these questions and research issues, and can contribute unique information concerning those relationships that existed in the distant (and not-so-distant) past between Caddo farmers. Twenty decorated sherds from the Musgano ceramic assemblage curated at the Texas Archeological Research Laboratory at The University of Texas at Austin (TARL) were selected for petrographic analysis. The sherds were split and one of the remaining fragments of each pair was used for the production of thin sections. Originally, the other half of each sherd was to be submitted for instrumental neutron activation analysis, but such analyses were not done; the remaining sherd fragment was returned for continued curation at TARL. Upon the receipt of the thin sections, they underwent petrographic analysis as reported on herein. The 20 sherds include sherds from engraved fine wares (n=8, 40 percent)—bottles and carinated bowls— as well as sherds from utility wares (n=12, 60 percent). The utility wares have brushed-appliqued, incised, incised-punctated (from Maydelle Incised, Weches Fingernail Impressed, and Washington Square Paneled vessels), and punctated decorative elements. Ten percent of the sherds are from bone-tempered vessels, based on macroscopic examination, while the others are from grog-tempered vessels

Decision Context, Associative Learning and Preference Formation in Risky Choic

Despite all the differences offered in theories of utility formation and decisions from experience/ descriptions, they share common assumption – decision makers have stable and coherent preferences, informed by consistent use of psychological strategy/processing (computational or sampling) that guide their choices between alternatives varying in risk and reward. In contrast, we argue for the non-existence of stable risk preferences; we propose that risk preferences are constructed dynamically based on strategy selection as a reinforcement-learning model. Accordingly, we found that decision context and associative learning predict strategy selection and govern risky preferences; rather having fixed preferences for risk, people select decision strategies from current context and learn to select decision strategies that are most successful (in terms of effort and reward) for a given context

Developments in the treatment for substance misuse offending

The drug treatment of offenders is a contentious issue steeped in political debate and clouded in media commentary about the rights of those who are estimated to commit up to half of the United Kingdom’s acquisitive crimes (HMG, 2008). The aim of this Chapter is to provide the reader with an overview of developments in the treatment for drug misuse offending. Initially, however, a general review of drugs and crime will be conducted. This will be followed by a background review of the development of treatment services in the United Kingdom and the second half of the chapter considers recent progress in treatments for drug misuse offenders

Recent experiences using finite-element-based structural optimization

Structural optimization has been available to the structural analysis community as a tool for many years. The popular use of displacement method finite-element techniques to analyze linearly elastic structures has resulted in an ability to calculate the weight and constraint gradients inexpensively for numerical optimization of structures. Here, recent experiences in the investigation and use of structural optimization are discussed. In particular, experience with the commercially available ADS/NASOPT code is addressed. An overview of the ADS/NASOPT procedure and how it was implemented is given. Two example problems are also discussed

Resonant Bend Loss in Leakage Channel Fibers

Leakage channel fibers, designed to suppress higher-order modes, demonstrate resonant power loss at certain critical radii of curvature. Outside the resonance, the power recovers to the levels offset by the usual mechanism of bend-induced loss. Using C$^2$-imaging, we experimentally characterize this anomaly and identify the corresponding physical mechanism as the radiative decay of the fundamental mode mediated by the resonant coupling to a cladding mode.Comment: 3 pages, 4 figures, submitted to Optics Letter