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Dig Reveals Story of America\u27s Last Slave Ship -- and its Survivors
Square set system of timbering as employed by the Shannon Copper Co.
The properties of The Shannon Copper Co., consisting of mine and smelter, are located in the Southeastern part of Arizona in what is known as the Clifton-Morenci District. The smelter is located at Clifton and the mine at Metcalf, eight miles distant on an iron capped mountain known as Serro Preito.
From a geological standpoint the ore deposits of the Clifton-Morenci District are a freak. There are no fissure veins of any consequence in the district; all the large deposits are found in bodies, the ore usually occurring in a soft porphyry.
Underlying the iron capping on the Shannon property the ground gives evidence of much disturbance, being cut with slips or faults that may run in any direction; also, in the same stope and with practically no difference in elevation, are found carbonate, oxide and sulphide ores. All the ore is found in bodies which have no definite shape and generally no walls, while some of the ore bodies are defined by one wall only, which evidences faulting at that point.
The system employed by the Shannon company in mining these ore bodies is that of square set, the object being to excavate all the ore in a body and completely fill the excavated portion with waste material in order to hold the ground in place. The material for filling is run into the stopes by chutes from open cuts on the surface, or by chutes from tunnels in which exporation work is being done --page 1
An Empirical Application of Laboratory Experimental Auctions in Marketing Research
A laboratory experimental auction was used to determine factors influencing the relative value consumers place on alternative retail beef packaging. Results indicate information is very important for the successful introduction and marketing of the vacuum skin package. Physical appearance of the beef plays a major role in purchasing decisions by consumers, with fat and shape significantly decreasing the value of beef in the vacuum skin package relative to beef in the overwrapped styrofoam tray package. Experimental economics procedures, when combined with traditional marketing research techniques, can provide useful information for marketing decisions and economic analyses
IMPACT OF CHANGING CONSUMER PREFERENCES ON WILLINGNESS-TO-PAY FOR BEEF STEAKS IN ALTERNATIVE RETAIL PACKAGING
The purpose of this study was to identify how consumer perceptions of selected attributes of beef steaks, individual consumer demographics and perceived changes in purchases of substitute meats affect willingness-to-pay for beef rib-eye steaks in the traditional overwrapped styrofoam tray and vacuum skin packages. A laboratory auction was used to obtain willingness-to-pay data. The results suggest that health related factors, particularly the concern regarding cholesterol, reduced the willingness-to-pay for beef rib-eye steaks, regardless of package type. For the vacuum skin package to be successful, information about the package is necessary, along with providing a consistent and quality product, particularly with respect to trim.Consumer/Household Economics,
A global range military transport: The ostrich
Studies have shown that there is an increasing need for a global range transport capable of carrying large numbers of troops and equipment to potential trouble spots throughout the world. The Ostrich is a solution to this problem. The Ostrich is capable of carrying 800,000 pounds 6,500 n.m. and returning with 15 percent payload, without refueling. With a technology availability date in 2010 and an initial operating capability of 2015, the aircraft incorporates many advanced technologies including laminar flow control, composite primary structures, and a unique multibody design. By utilizing current technology, such as using McDonnell Douglas C-17 fuselage for the outer fuselages on the Ostrich, the cost for the aircraft was reduced. The cost of the Ostrich per aircraft is 56,000 per flight hour. The Ostrich will provide a valuable service as a logistical transport capable of rapidly projecting a significant military force or humanitarian aid anywhere in the world
Greatly enhancing the modeling accuracy for distributed parameter systems by nonlinear time/space separation
An effective modeling method for nonlinear distributed parameter systems
(DPSs) is critical for both physical system analysis and industrial
engineering. In this Rapid Communication, we propose a novel DPS modeling
approach, in which a high-order nonlinear Volterra series is used to separate
the time/space variables. With almost no additional computational complexity,
the modeling accuracy is improved more than 20 times in average comparing with
the traditional method.Comment: 10 figures, 5 page
A non-destructive method for estimating onion leaf area
peer-reviewedWe would like to thank to the CICYT for funding the national project (AGL2007-66716-CO3-03), and the Education Regional Government of C-LM for funding the project (PCI08-0117).Leaf area is one of the most important parameters for characterizing crop growth and development, and its measurement is useful for examining the effects of agronomic management on crop production. It is related to interception of radiation, photosynthesis, biomass accumulation, transpiration and gas exchange in crop canopies. Several direct and indirect methods have been developed for determining leaf area. The aim of this study is to develop an indirect method, based on the use of a mathematical model, to compute leaf area in an onion crop using non-destructive measurements with the condition that the model must be practical and useful as a Decision Support System tool to improve crop management. A field experiment was conducted in a 4.75 ha commercial onion plot irrigated with a centre pivot system in Aguas Nuevas (Albacete, Spain), during the 2010 irrigation season. To determine onion crop leaf area in the laboratory, the crop was sampled on four occasions between 15 June and 15 September. At each sampling event, eight experimental plots of 1 m2 were used and the leaf area for individual leaves was computed using two indirect methods, one based on the use of an automated infrared imaging system, LI-COR-3100C, and the other using a digital scanner EPSON GT-8000, obtaining several images that were processed using Image J v 1.43 software. A total of 1146 leaves were used. Before measuring the leaf area, 25 parameters related to leaf length and width were determined for each leaf. The combined application of principal components analysis and cluster analysis for grouping leaf parameters was used to reduce the number of variables from 25 to 12. The parameter derived from the product of the total leaf length (L) and the leaf diameter at a distance of 25% of the total leaf length (A25) gave the best results for estimating leaf area using a simple linear regression model. The model obtained was useful for computing leaf area using a non-destructive method.CICYTEducation Regional Government of C-L
Background and Method of the Striving to be Strong Study a RCT Testing the Efficacy of a M-health Self-management Intervention
Background
Osteoporosis is a prevalent and debilitating condition affecting \u3e50% of post-menopausal women. Yet, a low percentage of women regularly engage in health promoting behaviors associated with osteoporosis prevention. Complex, multidimensional, m-Health interventions hold promise to effect engagement in health behavior change related to calcium and vitamin D intake, balance, core and leg strength, and physical activity. Methods
Striving to be Strong study (R01NR013913-01) tests the efficacy of a research and theory based, patient centered, dynamically tailored intervention delivered via smart phone apps. Ecological Momentary Assessments (EMAs) enhance immediate feedback and complement traditional measures. The desired outcomes are the maintenance of osteoporosis self-management behaviors and a decrease in the loss of bone density over time. The Individual and Family Self-management Theory provided the conceptual foundation for the study. The sample consists of 290 healthy women between the ages of 40 and 60 with an anticipated attrition of 33%. This three group repeated measures Randomized Clinical Trial spans a 12-month time period. Data collected occurs via web site, smart-phone app, self-report, observation, and measures. Proximal (engagement in osteoporosis health behaviors) and distal (serum vitamin D, DXA, and body composition) outcomes are collected for testing of the efficacy of the intervention and theory evaluation. Discussion
Active and rigorous quality management processes continually evaluate enrollment and retention goals, functionality of the automated intervention delivery and data collection systems, EMAs, and dispersion of incentives
Spatially explicit models of dynamic histories: examination of the genetic consequences of Pleistocene glaciation and recent climate change on the American Pika
A central goal of phylogeography is to identify and characterize the processes underlying divergence. One of the biggest impediments currently faced is how to capture the spatiotemporal dynamic under which a species evolved. Here, we described an approach that couples species distribution models (SDMs), demographic and genetic models in a spatiotemporally explicit manner. Analyses of American Pika ( Ochotona princeps ) from the sky islands of the central Rocky Mountains of North America are used to provide insights into key questions about integrative approaches in landscape genetics, population genetics and phylogeography. This includes (i) general issues surrounding the conversion of time‐specific SDMs into simple continuous, dynamic landscapes from past to current, (ii) the utility of SDMs to inform demographic models with deme‐specific carrying capacities and migration potentials as well as (iii) the contribution of the temporal dynamic of colonization history in shaping genetic patterns of contemporary populations. Our results support that the inclusion of a spatiotemporal dynamic is an important factor when studying the impact of distributional shifts on patterns of genetic data. Our results also demonstrate the utility of SDMs to generate species‐specific predictions about patterns of genetic variation that account for varying degrees of habitat specialization and life history characteristics of taxa. Nevertheless, the results highlight some key issues when converting SDMs for use in demographic models. Because the transformations have direct effects on the genetic consequence of population expansion by prescribing how habitat heterogeneity and spatiotemporal variation is related to the species‐specific demographic model, it is important to consider alternative transformations when studying the genetic consequences of distributional shifts.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/92413/1/j.1365-294X.2012.05640.x.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/92413/2/MEC_5640_sm_FigureS3.pd
Searching for Better Plasmonic Materials
Plasmonics is a research area merging the fields of optics and
nanoelectronics by confining light with relatively large free-space wavelength
to the nanometer scale - thereby enabling a family of novel devices. Current
plasmonic devices at telecommunication and optical frequencies face significant
challenges due to losses encountered in the constituent plasmonic materials.
These large losses seriously limit the practicality of these metals for many
novel applications. This paper provides an overview of alternative plasmonic
materials along with motivation for each material choice and important aspects
of fabrication. A comparative study of various materials including metals,
metal alloys and heavily doped semiconductors is presented. The performance of
each material is evaluated based on quality factors defined for each class of
plasmonic devices. Most importantly, this paper outlines an approach for
realizing optimal plasmonic material properties for specific frequencies and
applications, thereby providing a reference for those searching for better
plasmonic materials.Comment: 27 pages, 6 figures, 2 table
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