858 research outputs found
Potential Biomass Yields in the South Central US
This paper describes research to create a national database of switchgrass supply as part of the biomass program launched by the Department of Energy. The paper provides an estimate of county level switchgrass yield data for the state of Oklahoma. The estimates are made for the top five most productive and abundant soils for each county in Oklahoma. A simple approach of ratio calculation and estimation is used to predict the switchgrass yield of one soil type by comparing it with the yield of several other crops in another soil type. The data for switchgrass yield for a particular soil type are obtained from the state research experiment stations. The yields for other crops for the top five soils are obtained from the NASS data sources. Switchgrass supply for Oklahoma was estimated to be 49.5 million tons from the top soils with the Northeast crop reporting district to be the dominant supplier.Biofuel, Switchgrass, Ratio Estimation, South Central, Oklahoma, Agricultural and Food Policy, Crop Production/Industries, Environmental Economics and Policy, Production Economics, Productivity Analysis, Research and Development/Tech Change/Emerging Technologies, Resource /Energy Economics and Policy,
Selecting Site Suitable for Animal Waste Application using a Vector GIS
Due to the increase in the number and size of intensive animal industries (IAI) in many parts of the world including Australia, the disposal of animal waste has become a pressing environmental problem. Frequently the wastes generated at IAI are conveniently, favourably, and cost-effectively applied to the nearby agricultural fields to recycle manure nutrients. However, excessive application of wastes in the nearby fields without due consideration of site-specific factors (eg. slope, soil, and watercourses) has resulted in the run-off and leaching losses of manure nutrients causing agricultural non-point source (NPS) pollution (He and Shi, 1998). The agricultural NPS pollution has contributed significantly to the eutrophication and toxic blue green algae blooms in many river systems including Murray-Darling, where world's largest toxic riverine algal bloom was recorded in 1991 (Kuhn, 1993). Hence it has become crucial to develop an animal waste application guide (i.e. a site suitability map) by considering biophysical and socio-economic factors to minimise the environmental hazards. Developing such a map requires consideration of many factors and their spatial variability. Geographic information system (GIS)offers site suitability analysis techniques that are capable of processing large volumes of spatial data (Davis, 1996). The objective of this study is to develop a suitability map using a vector GIS, and to evaluate the factor sensitivity and aptness of this technique in selecting suitable sites for animal waste application
Towards portable muography with small-area, gas-tight glass Resistive Plate Chambers
Imaging techniques that use atmospheric muons, collectively named under the
neologism "muography", have seen a tremendous growth in recent times, mainly
due to their diverse range of applications. The most well-known ones include
but are not limited to: volcanology, archaeology, civil engineering, nuclear
reactor monitoring, nuclear waste characterization, underground mapping, etc.
These methods are based on the attenuation or deviation of muons to image large
and/or dense objects where conventional techniques cannot work or their use
becomes challenging.
In this context, we have constructed a muography telescope based on "mini
glass-RPC planes" following a design similar to the glass-RPC detectors
developed by the CALICE Collaboration and used by the TOMUVOL experiment in the
context of volcano radiography, but with smaller active area (16 16
cm). The compact size makes it an attractive choice with respect to other
detectors previously employed for imaging on similar scales. An important
innovation in this design is that the detectors are sealed. This makes the
detector more portable and solves the usual safety and logistic issues for gas
detectors operated underground and/or inside small rooms. This paper provides
an overview on our guiding principles, the detector development and our
operational experiences. Drawing on the lessons learnt from the first
prototype, we also discuss our future direction for an improved second
prototype, focusing primarily on a recently adopted serigraphy technique for
the resistive coating of the glass plates.Comment: 8 pages, 7 figures, XV Workshop on Resistive Plate Chambers and
Related Detectors (RPC2020
Line tension and structure of smectic liquid crystal multilayers at the air-water interface
At the air/water interface, 4,-8-alkyl[1,1,-biphenyl]-4-carbonitrile (8CB)
domains with different thicknesses coexist in the same Langmuir film, as
multiple bilayers on a monolayer. The edge dislocation at the domain boundary
leads to line tension, which determines the domain shape and dynamics. By
observing the domain relaxation process starting from small distortions, we
find that the line tension is linearly dependent on the thickness difference
between the coexisting phases in the film. Comparisons with theoretical
treatments in the literature suggest that the edge dislocation at the boundary
locates near the center of the film, which means that the 8CB multilayers are
almost symmetric with respect to the air/water interface.Comment: 21 pages, 6 figure
Controlled electrochemical growth of ultra-long gold nanoribbons
Citation: Basnet, G., Panta, K. R., Thapa, P. S., & Flanders, B. N. (2017). Controlled electrochemical growth of ultra-long gold nanoribbons. Applied Physics Letters, 110(7), 5. doi:10.1063/1.4976027This paper describes the electrochemical growth of branchless gold nanoribbons with similar to 40 nm x similar to 300 nm cross sections and >100 mu m lengths (giving length-to-thickness aspect ratios of > 10(3)). These structures are useful for opto-electronic studies and as nanoscale electrodes. The 0.75-1.0V voltage amplitude range is optimal for branchless ribbon growth. Reduced amplitudes induce no growth, possibly due to reversible redox chemistry of gold at reduced amplitudes, whereas elevated amplitudes, or excess electrical noise, induce significant side-branching. The inter-relatedness of voltage-amplitude, noise, and side-branching in electrochemical nanoribbon growth is demonstrated. Published by AIP Publishing
Laser-Induced Electron Emission from Au Nanowires: A Probe for Orthogonal Polarizations
Photoelectron field emission, induced by femtosecond laser pulses focused on metallic nanotips, provides spatially coherent and temporally short electron pulses. The properties of the photoelectron yield give insight into both the material properties of the nanostructure and the exciting laser focus. Ultralong nanoribbons, grown as a single crystal attached to a metallic taper, are sources of electron field emission that have not yet been characterized. In this report, photoemission from gold nanoribbon samples is studied and compared to emission from tungsten and gold tips. We observe that the emission from sharp tips generally depends on one transverse component of the exciting laser field, while the emission of a blunted nanoribbon is found to be sensitive to both components. We propose that this property makes photoemission from nanoribbons a candidate for position-sensitive detection of the longitudinal field component in a tightly focused beam
The vaginal-PVPA: A vaginal mucosa-mimicking in vitro permeation tool for evaluation of mucoadhesive formulations
Drug administration to the vaginal site has gained increasing attention in past decades, highlighting the need for reliable in vitro methods to assess the performance of novel formulations. To optimize formulations destined for the vaginal site, it is important to evaluate the drug retention within the vagina as well as its permeation across the mucosa, particularly in the presence of vaginal fluids. Herewith, the vaginal-PVPA (Phospholipid Vesicle-based Permeation Assay) in vitro permeability model was validated as a tool to evaluate the permeation of the anti-inflammatory drug ibuprofen from liposomal formulations (i.e., plain and chitosan-coated liposomes). Drug permeation was assessed in the presence and absence of mucus and simulated vaginal fluid (SVF) at pH conditions mimicking both the healthy vaginal premenopausal conditions and vaginal infection/pre-puberty/post-menopause state. The permeation of ibuprofen proved to depend on the type of formulation (i.e., chitosan-coated liposomes exhibited lower drug permeation), the mucoadhesive formulation properties and pH condition. This study highlights both the importance of mucus and SVF in the vaginal model to better understand and predict the in vivo performance of formulations destined for vaginal administration, and the suitability of the vaginal-PVPA model for such investigations
Development and Validation of an Information Booklet Aimed at Promoting Mental Health for Pregnant Women with a History of Abuse.
BACKGROUND:Mental health needs of victims of domestic and family violence are often overlooked. A booklet was designed to help women update their knowledge and skills in effective coping with domestic and family violence and support them in developing effective stress reduction and problem management techniques. In addition, this booklet is believed to serve as a reference for further use. This paper describes the development process and validation of the information booklet. This booklet was used during an intervention trial conducted in Nepal to educate abused pregnant women. METHODS:This methodological study involved three stages: bibliographical survey, development of the booklet, and validation by specialists in the relevant fields and representatives of the target audiences. A total of eight experts, currently working in the field of domestic violence and/or midwifery, and 15 representatives of the target participants were involved in the validation process. A minimum Content Validity Index of 0.78 was considered for content validation, and minimum agreement of 75% for face validation. RESULTS:The booklet presented a global Content Validity Index of 0.92. The overall level of agreement within the target participants was 86.3%, which was higher than the minimum recommended level. Both subject experts and participants positively evaluated the adequacy, coverage and readability of contents of the booklet. CONCLUSIONS:The booklet was validated using content and face validity. This validated booklet is expected to be an effective tool for communication that would help pregnant women cope better with domestic and family violence and adopt strategies to remain emotionally healthy
Metformin and Myocardial Injury in Patients With Diabetes and ST-Segment Elevation Myocardial Infarction: A Propensity Score Matched Analysis
BACKGROUND: Although animal studies have documented metformin's cardioprotective effects, the impact in humans remains elusive. The study objective was to explore the association between metformin and myocardial infarct size in patients with diabetes presenting with ST‐segment elevation myocardial infarction. METHODS AND RESULTS: Data extraction used the National Cardiovascular Data CathPCI Registry in all patients with diabetes aged >18 years presenting with ST‐segment elevation myocardial infarction at 2 academic medical centers from January 2010 to December 2013. The exposure of interest was ongoing metformin use before the event. Propensity score matching was used for the metformin and nonmetformin groups on key prognostic variables. All matched pairs had acceptable D scores of <10%, confirming an efficient matching procedure. The primary outcome was myocardial infarct size, reflected by peak serum creatine kinase–myocardial band, troponin T, and hospital discharge left ventricular ejection fraction. Of all 1726 ST‐segment elevation myocardial infarction cases reviewed, 493 patients had diabetes (28.5%), with 208 metformin users (42.1%) and 285 nonusers. Matched pairs analysis yielded 137 cases per group. The difference between metformin and nonmetformin groups was −18.1 ng/mL (95% CI −55.0 to 18.8; P=0.56) for total peak serum creatine kinase–myocardial band and −1.1 ng/mL (95% CI −2.8 to 0.5; P=0.41) for troponin T. Median discharge left ventricular ejection fraction in both groups was 45, and the difference between metformin and nonmetformin users was 0.7% (95% CI −2.2 to 3.6; P=0.99). CONCLUSIONS: No statistically significant association of cardioprotection was found between metformin and myocardial infarct size in patients with diabetes and acute ST‐segment elevation myocardial infarction
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