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Loss A.,Federal University of Santa Catarina | Pereira M.G.,Federal Rural University of Rio de Janeiro | Costa E.M.,Brazilian National Council for Scientific and Technological Development | Beutler S.J.,IA
Bioscience Journal | Year: 2014

This study aimed to quantify the total organic carbon (TOC), granulometric and oxidizable carbon fractions of soil organic carbon (SOM) in areas under different land use in Marmeleiro, Paraná State, Brazil. We collected soil samples in the 0-5, 5-10, 10-20 and 20-40 cm, and being these quantified to TOC, particulate organic carbon (POC), organic carbon associated minerals (OCam) and carbon fractions oxidizable (F1, F2, F3, F4 and F1/F4). The notillage system (NTS) had higher TOC values (0-5 cm) and the conventional tillage system (CTS), the lowest (0-5 and 5-10 cm). The NTS and the grazing area had higher concentrations of POC (0-5 cm). In the CTS there were the lowest levels of POC in surface and greater depth. The lower carbon content of oxidizable fractions were found in the CTS (0-10 cm). The NTS increase the TOC, and POC oxidisable carbon (F1, F4) in the surface layer when compared to the CTS. This leads to TOC area equal to the NTS in depth and leads to decreased amounts of carbon and OCam oxidizable fraction F4 in all experiments. Through the F1/F4 ratio can be inferred that the CTS disfavors the balance of fractions F1 and F4, while the NTS leads to values similar to those in areas without human interference. The granulometric and oxidizable fractions of SOM are efficient to identify changes in soil caused by management. Source


Kamp B.J.,University of Wales | Wellman N.S.,Tufts University | Russell C.,IA
Journal of Nutrition Education and Behavior | Year: 2010

Given the federal cost-containment policy to rebalance long-term care away from nursing homes to home- and community-based services, it is the position of the American Dietetic Association, the American Society for Nutrition, and the Society for Nutrition Education that all older adults should have access to food and nutrition programs that ensure the availability of safe, adequate food to promote optimal nutritional status. Appropriate food and nutrition programs include adequately funded food assistance and meal programs, nutrition education, screening, assessment, counseling, therapy, monitoring, evaluation, and outcomes documentation to ensure more healthful aging. The growing number of older adults, the health care focus on prevention, and the global economic situation accentuate the fundamental need for these programs. Yet far too often food and nutrition programs are disregarded or taken for granted. Growing older generally increases nutritional risk. Illnesses and chronic diseases; physical, cognitive, and social challenges; racial, ethnic, and linguistic differences; and low socioeconomic status can further complicate a situation. The beneficial effects of nutrition for health promotion, risk reduction, and disease management need emphasis. Although many older adults are enjoying longer and more healthful lives in their own homes, others, especially those with health disparities and poor nutritional status, would benefit from greater access to food and nutrition programs and services. Food and nutrition practitioners can play a major role in promoting universal access and integrating food and nutrition programs and nutrition services into home- and community-based services. © 2010 The American Dietetic Association, the American Society for Nutrition, and the Society for Nutrition Education. Source


Mao X.,Samsung | Rapids C.,IA | Morton Y.,Miami University Ohio
26th International Technical Meeting of the Satellite Division of the Institute of Navigation, ION GNSS 2013 | Year: 2013

Ionosphere scintillation is a nuisance for space-based radio systems such as GNSS. Because of the effects of ionosphere scintillation and the well-defined GNSS signal structures, GNSS signals can be used as a signal of opportunity to study ionosphere and space weather phenomena. GNSS signal parameter disturbances can be used to infer the underlying processes occurred in the ionosphere propagation medium. The objective of this paper is to obtain accurate estimations of scintillating GNSS signal parameters for ionosphere studies. The conventional way to estimate the GNSS signal carrier phase and C/N0 is through carrier phase tracking. Depending on how the carrier phase tracking is implemented, artifacts maybe introduced into the parameter estimations. This paper investigates the receiver processing artifacts in carrier phase and carrierto-noise ratio and presents approaches that correct or minimize these artifacts. Source


Vanhille C.,Rey Juan Carlos University | Campos-Pozuelo C.,IA
Ultrasonics Sonochemistry | Year: 2011

We present the results of numerical predictions for analyzing the behavior of nonlinear ultrasonic standing waves in two-dimensional cavities filled with bubbly liquids. The model we solve accounts for nonlinearity, dissipation, and dispersion of the two-dimensional media due to the bubbles. The numerical simulations are based on a finite-difference scheme. They consider the bubbles evenly distributed in the liquid. Results are shown for high-amplitude signals. They make it possible to observe how the linear modes turn into multi-frequency nonlinear fields. © 2010 Elsevier B.V. Source


Seo J.,Iowa State University | Phares B.,Iowa State University | Lu P.,IA | Wipf T.,Iowa State University | Dahlberg J.,Iowa State University
Engineering Structures | Year: 2013

A protocol for the development of a set of load rating distributions for a steel I-girder bridge will be presented. The critical regions of the bridge were instrumented using strain sensors to measure the real-time strain time history resulting from ambient trucks. This study focused on five-axle trucks traveling the south-lane of the bridge. Strain time history data was used to calibrate finite element models according to two scenarios: known and unknown truck characteristic selections. These truck characteristics identified from Weight-In-Motion (WIM) data obtained from Iowa state highways were used in the model calibration. The calibrated models, along with standard HS-20 trucks following AASHTO Load Factor Rating (LFR) method, were used to calculate a set of load ratings for each strain set as per the scenarios. Multiple load rating distributions created for strain sets were combined into a single holistic distribution. For the proposed protocol verification, the distribution was compared to that obtained from a rating package currently used by the Iowa Department of Transportation (Iowa DOT). The resulting distribution sets had means of 1.36 and 1.41 for known and unknown truck selections, respectively and subsequently were 24% and 27% greater than those values obtained from the Iowa DOT rating package. The distribution can be used not only to statistically evaluate structural capacity of such bridges, but also provide essential information for assigning retrofit prioritization of such bridges. © 2012 Elsevier Ltd. Source

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