7,362 research outputs found
Small axial turbine stator technology program
An experimental investigation was conducted to determine the effects of surface finish, fillet radius, inlet boundary layer thickness, and free-stream inlet turbulence level on the aerodynamic performance of a small axial flow turbine stator. The principal objective of this program was to help understand why large turbine efficiency is not maintained when a large turbine is scaled to a smaller size. The stator used in this program as a one-sixth scale of a 762 mm (30 in.) diameter stator design with 50 vanes having a vane height of 17 mm (0.666 in.) and an aspect ratio of 1.77. A comprehensive overall test matrix was used to provide a complete engineering understanding of the effects of each variable over the full range of all the other variables. The range of each variable investigated was as follows: surface finish 0.1 micro (4 micro in.) to 2.4 micro (95 micro in.); boundary layer thickness 2 to 25 percent of channel height at each wall; fillet radius 0 mm (0 in.) to 1.0 mm (.040 in.) and turbulence 2 to 12 percent
Funneled angle landscapes for helical proteins
We use crystallographic data for four helical iron proteins (cytochrome c-b₅₆₂, cytochrome c′, sperm whale myoglobin, human cytoglobin) to calculate radial and angular signatures as each unfolds from the native state stepwise though four unfolded states. From these data we construct an angle phase diagram to display the evolution of each protein from its native state; and, in turn, the phase diagram is used to construct a funneled angle landscape for comparison with the topography of its folding energy landscape. We quantify the departure of individual helical and turning regions from the areal, angular profile of corresponding regions of the native state. This procedure allows us to identify the similarities and differences among individual helical and turning regions in the early stages of unfolding of the four helical heme proteins
International Service Learning: Catalyst for transformation in language learner identity?
An ever increasing number of North American universities offer International Service Learning (ISL) programs to meet the interests of civic minded students hoping to gain international experience and develop cultural awareness while, at the same time, “making a difference” to a community in need. While there is an abundance of anecdotal accounts to support the claims that combining study abroad experiences with service-learning pedagogy has great transformative learning potential, there is a lack of reliable evidence (Grusky, 2000). This paper will present the theoretical framework of the author’s doctoral research; a qualitative study exploring the link between cultural sensitivity and student investment in language acquisition by following Spanish language learners participating in a short term international service learning program. I focus on the transformation (Kiely, 2004) in students’ cultural sensitivity due to the interactions with host communities during the “service” portion of the ISL component and how this cultural awakening in turn transforms the students’ social identities and their investment in acquiring the target language (Norton, 1995).Grusky, S. (2000). International service learning: A critical guide from an impassioned advocate. American Behavioral Scientist, 43(5), 858-867. Kiely, R. (2004). A Chameleon with a complex: Searching for transformation in international service-learning. Michigan Journal of Community Service Learning, 10(2), 5-20.Norton Peirce, B. (1995). Social identity, investment, and language learning. TESOL Quarterly, 29(1), 9-31.
Institutions and government growth: a comparison of the 1890s and the 1930s
Statistics on the size and growth of the U.S. federal government, in addition to public statements by President Franklin Roosevelt, seem to indicate that the Great Depression was the primary event that caused the dramatic growth in government spending and intervention in the private sector that continues to the present day. Through a comparison of the economic conditions of the 1890s and the 1930s, the authors argue that post-1930 government growth in the United States is not the direct result of the Great Depression, but rather is a result of institutional, legal, and societal changes that began in the late 1800s. Thus, the Great Depression did likely trigger increases in government spending and regulatory involvement, but historical factors produced the conditions that tended to lend permanence to the growth of government that occurred during the Great Depression.Federal government ; Depressions
Naturally Occurring Polymorphisms of the Mouse Gammaretrovirus Receptors CAT-1 and XPR1 Alter Virus Tropism and Pathogenicity
Gammaretroviruses of several different host range subgroups have been isolated from laboratory mice. The ecotropic viruses infect mouse cells and rely on the host CAT-1 receptor. The xenotropic/polytropic viruses, and the related human-derived XMRV, can infect cells of other mammalian species and use the XPR1 receptor for entry. The coevolution of these viruses and their receptors in infected mouse populations provides a good example of how genetic conflicts can drive diversifying selection. Genetic and epigenetic variations in the virus envelope glycoproteins can result in altered host range and pathogenicity, and changes in the virus binding sites of the receptors are responsible for host restrictions that reduce virus entry or block it altogether. These battleground regions are marked by mutational changes that have produced 2 functionally distinct variants of the CAT-1 receptor and 5 variants of the XPR1 receptor in mice, as well as a diverse set of infectious viruses, and several endogenous retroviruses coopted by the host to interfere with entry
Standards, Standards, Where might you be?
Getting access to standards can prove to be a tricky and expensive endeavor. The Lichtenberger Engineering Library at the University of Iowa has been working to try and simplify the process in order to provide a greater depth of available standards for free to students, faculty, and staff.
Finding and accessing standards can be a complex task since there are hundreds of agencies or organizations that produce standards, with each one having their own set of rules and regulations on how they can be viewed and distributed. There is unfortunately no one place that lists all existing standards. A student often needs to search multiple databases or indexes to fully see what is available in their area of study. Once they find the standards they are looking for, it is time to actually find access to the full text. Standards often cannot be requested through loans from other libraries due to copyright restrictions, which makes the process all that more complicated. They also are not regularly listed in library catalogs since they are so hard to catalog and change frequently.
Over the last couple of years, the Library has worked to provide electronic access to as many standards as possible, and to educate the students about the availability of standards in the library. The Library has access to an online database called TechStreet that provides access to standards by 48 different publishers and has searchable abstracts for others. It is still not all inclusive, but it is getting better. There is also electronic access to over half a dozen individual agencies or organizations standards through separate subscriptions. For those standards that are not part of any electronic packages, the library orders them in print to be housed in the Library.
To help with the complexity of searching and accessing these standards, the librarian visits various classes each semester to give an overview of what standards are, as well as providing instruction on gaining access to individual standards. These sessions, along with projects assigned in the courses, help students gain an understanding of the importance of standards in industry today
The mouse "xenotropic" gammaretroviruses and their XPR1 receptor
The xenotropic/polytropic subgroup of mouse leukemia viruses (MLVs) all rely on the XPR1 receptor for entry, but these viruses vary in tropism, distribution among wild and laboratory mice, pathogenicity, strategies used for transmission, and sensitivity to host restriction factors. Most, but not all, isolates have typical xenotropic or polytropic host range, and these two MLV tropism types have now been detected in humans as viral sequences or as infectious virus, termed XMRV, or xenotropic murine leukemia virus-related virus. The mouse xenotropic MLVs (X-MLVs) were originally defined by their inability to infect cells of their natural mouse hosts. It is now clear, however, that X-MLVs actually have the broadest host range of the MLVs. Nearly all nonrodent mammals are susceptible to X-MLVs, and all species of wild mice and several common strains of laboratory mice are X-MLV susceptible. The polytropic MLVs, named for their apparent broad host range, show a more limited host range than the X-MLVs in that they fail to infect cells of many mouse species as well as many nonrodent mammals. The co-evolution of these viruses with their receptor and other host factors that affect their replication has produced a heterogeneous group of viruses capable of inducing various diseases, as well as endogenized viral genomes, some of which have been domesticated by their hosts to serve in antiviral defense
Сoncerning the Question of Maintenance and Renewal of Cultural Landscape Around Wooden Church of Holy Spirit in Potelycz Village
Показано краєзнавчу цінність села Потелича Жовківського району Львівської області з дерев’яною церквою Святого Духа. Запропоновано сучасні способи відновлення (зокрема нові технології тривимірної візуалізації) та збереження ландшафту навколо сакральної дерев’яної пам’ятки.In the work there was shown local history value of Potelycz village of Zhovkva region, Lviv district taking into account wooden church of Holy Spirit. Contemporary techniques of restoration (including innovative 3D visualization technologies) and maintenance of landscape around sacral wooden monument were presented as well
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