423 research outputs found
Estimating sorber capacity for multiple contaminants
Computer program estimates quantity of activated charcoal required to control multiple contaminants. Program scans all contaminants by potential parameter value and then orders them from lowest to highest values. It calculates quantity of sorbent required to remove most strongly adsorbed material; and then, using potential plot data, capacity of other materials is calculated on basis of corrected capacity
What makes good climbing rock? A petrographic, structural, and mechanical investigation of the lower Nuttall Sandstone in the New River Gorge, West Virginia
The New River Gorge National River (NERI) consists of 300 km2 of public land including an 85 km length of the New River, covering parts of Summers, Raleigh, and Fayette counties in West Virginia (National Park Service, 2006). NERI is known for world class rock climbing because the Pennsylvanian lower Nuttall Sandstone of the Pottsville Group forms 15 to 30 m high cliffs along the gorge walls, containing more than 1500 documented climbing routes. This project investigates why the lower Nuttall Sandstone in NERI creates one of the premiere climbing areas in the Eastern United States, and why the lower Nuttall Sandstone is climbed instead of other cliff-forming sandstones in the gorge. Outcrop investigations on climbed routes, including rebound hammer determinations, show the lower Nuttall Sandstone\u27s competence, level of surface features, jointing, and bedding are controlling variables acting on climbing desirability. Ranked level of surface features assigned based on field observations is correlated with climbing grade and popularity. Thin sections sampled from the lower Nuttall Sandstone and other sandstones document petrology as it affects rock competence.;The most desirable stratigraphic interval for expert climbers is a 15 to 20 m interval in the lower Nuttall Sandstone composed of homogenous quartz arenite that lacks partings along bedding planes. Throughout NERI, a basal conglomerate in the lower Nuttall Sandstone and an underlying shale unit are less mechanically strong and less resistant to weathering than the massively bedded quartz arenite layers above. Differential erosion, combined with widely spaced vertical tectonic joints, leads to large blocks of overlying lower Nuttall Sandstone failing in a predictable pattern, creating planar cliff faces and opening joints that provide climbing appeal. Lower Nuttall Sandstone cliffs and blocks contain goethite as a secondary cement along tectonic joints, which add to the rock\u27s resistant nature. The competence of the rock appeals to climbers because the lower Nuttall Sandstone is relatively safe for climbing. Differential weathering of sandstone behind areas with goethite cement, and weathering along bedding and other sedimentary structures have created surface features that increase climbing desirability. Other cliff-forming New River Group sandstones in NERI have not been widely developed for expert climbing because they exhibit more heterogeneity and are more thinly bedded, making them less challenging for expert climbers
Literacy Co-Teaching with Multi-level Texts in an Inclusive Middle Grade Humanities Class: A Teacher-Researcher Collaboration
This article reports on a middle school literacy intervention implemented during a yearlong teacher-researcher collaboration. The purpose of this collaboration was to combine and adjust commonly recommended pedagogical approaches to address the literacy needs of a heterogeneous group of seventh graders attending an urban school. University researchers designed and implemented the intervention with an interdisciplinary team of three teachers. The intervention drew on sociocultural theories of language and learning. It had three main features: integration of English and social studies, multi-level texts, and co-teaching of heterogeneous groups. Qualitative data included field notes from classroom observations and planning meetings, transcripts from teacher interviews, and classroom artifacts. Data were analyzed as they were collected and used in planning sessions. Additional analysis after the intervention ended focused on exploration of critical events reflecting convergence and divergence of teachers\u27 and researchers\u27 perspectives on the intervention features. Findings were organized around three representative critical events, one per intervention feature. Implications of results for future middle grade co-teaching literacy interventions were explored
Antioxidants and the Autoxidation of Fats v. Mode of Action of Anti- and Pro-Oxidants
Experiments on the oxidation of purified methyl oleate support the view that its induction period, and probably that of natural oils, is due to the presence of inhibitors and that purified unsaturated compounds have no induction period, other than the time required for gaseous oxygen to diffuse into the liquid
Evaluation testing of zero gravity humidity control system
Design criteria for zero gravity hydrophobic/ hydrophilic type humidity control syste
Enigmatic Red Beds Exposed at Point of Rocks, Cimarron National Grassland, Morton County, Kansas: Chronostratigraphic Constraints from Uranium-Lead Dating of Detrital Zircons
Point of Rocks, a high-relief bluff overlooking the Cimarron River valley in Morton County, Kansas, is capped by distinct white beds of Neogene Ogallala Formation calcrete that overlie red beds of shale, siltstone, and sandstone. These unfossiliferous red beds are currently assigned to the Jurassic System; however, their age has long been debated due to a lack of marker beds, index fossils, and nearby correlative outcrops. As a result, geologists over the years have assigned the rocks to systems ranging from the Permian to the Cretaceous. In this study, four stratigraphic sections were measured in the red beds and three bulk samples were collected to determine the uranium-lead age distributions of detrital zircon (DZ) populations. Red-bed strata composed of fissile shale and sandstone are interpreted as alluvial overbank deposits, while dominantly trough cross-bedded and planar-laminated sandstones are interpreted as tidally influenced fluvial deposits. Detrital zircon age peaks can be grouped into at least seven subpopulations with a youngest single zircon age of 263.8 ± 12.1 Ma, a more conservative age of 293.0 ± 6.95 Ma based on the youngest grouping of three grain ages overlapping at 2σ, and a complete absence of Mesozoic age zircons. In addition, copper oxides along partings and fractures suggest that the red beds once hosted copper sulfides, a common constituent of regional Permian-Triassic red beds. The DZ data--in conjunction with the identification of the Permian Day Creek Dolomite marker bed in logs of nearby drilling tests--strongly suggest that the enigmatic red beds cropping out at the base of Point of Rocks should be assigned to the Guadalupian Big Basin Formation, the uppermost Permian unit in Kansas
Higher Education in Tajikistan: Institutional Landscape and Key Policy Developments
Higher education in Tajikistan has undergone substantial changes over the past 25 years as a result of both its internal crises and those social and economic transition challenges seen throughout the Newly Independent States (NIS). HEIs in the country have also shown eagerness to change and grow as they move toward world education space. In this chapter, we examine the evolution of the Tajik system of higher education from the Soviet time through independence (1991–2015) in terms of growth, emerging landscape and diversification, and key policy developments and issues. We analyze these changes in the context of relevant economic, social and political factors, and rely on a comparative analysis in understanding the commonalities and differences in higher educational landscapes between Tajikistan and others in the NIS. Institutional diversity has occurred in the country along several dimensions. Among these is a geometric expansion of the number of HEIs: Those transformed from preexisting Soviet institutes as well as the establishment of many new ones. This has been fueled partly by the mass creation of new programs that reflect the needs of an emerging knowledge-based economy but also the result of parental craving for higher education for their children—regardless of market demands. Specific features of the massification of higher education in Tajikistan are further explained by internationalization according to the Bologna Process and other globalization agendas; the establishment of international HEIs under bilateral government agreements (with Russia), and significantly increasing HEI programs and enrolments in far-flung regions of the country—especially in programs related to industry and technology. Our analyses are based on a variety of official statistical sources; educational laws, institutional documents and reports published by international organizations; accounts from the English-language press; and open-ended interviews conducted by the authors in Tajikistan between 2011 and 2014
Biomarker Evidence for Photosynthesis During Neoproterozoic Glaciation
Laterally extensive black shales were deposited on the São Francisco craton in southeastern Brazil during low-latitude Neoproterozoic glaciation ∼740 to 700 million years ago. These rocks contain up to 3.0 weight % organic carbon, which we interpret as representing the preserved record of abundant marine primary productivity from glacial times. Extractable biomarkers reflect a complex and productive microbial ecosystem, including both phototrophic bacteria and eukaryotes, living in a stratified ocean with thin or absent sea ice, oxic surface waters, and euxinic conditions within the photic zone. Such an environment provides important constraints for parts of the “Snowball Earth” hypothesis
A global outlook to the interruption of education due to COVID-19 Pandemic: Navigating in a time of uncertainty and crisis
Uncertain times require prompt reflexes to survive and this study is a collaborative reflex to
better understand uncertainty and navigate through it. The Coronavirus (Covid-19) pandemic hit hard
and interrupted many dimensions of our lives, particularly education. As a response to interruption of
education due to the Covid-19 pandemic, this study is a collaborative reaction that narrates the overall
view, reflections from the K12 and higher educational landscape, lessons learned and suggestions from
a total of 31 countries across the world with a representation of 62.7% of the whole world population. In
addition to the value of each case by country, the synthesis of this research suggests that the current
practices can be defined as emergency remote education and this practice is different from planned
practices such as distance education, online learning or other derivations. Above all, this study points
out how social injustice, inequity and the digital divide have been exacerbated during the pandemic and
need unique and targeted measures if they are to be addressed. While there are support communities
and mechanisms, parents are overburdened between regular daily/professional duties and emerging
educational roles, and all parties are experiencing trauma, psychological pressure and anxiety to various
degrees, which necessitates a pedagogy of care, affection and empathy. In terms of educational
processes, the interruption of education signifies the importance of openness in education and highlights
issues that should be taken into consideration such as using alternative assessment and evaluation
methods as well as concerns about surveillance, ethics, and data privacy resulting from nearly exclusive
dependency on online solutions
Correction of axial and rotational alignment after medial and lateral releases during balanced gap TKA: A clinical study of 54 patients
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