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Articles 139591 - 139620 of 303247
Full-Text Articles in Physical Sciences and Mathematics
Assessing Small And Medium-Sized Farmers' Willingness To Produce Alternative Biofuel Feedstocks, Andra Johnson, Charles Butler
Assessing Small And Medium-Sized Farmers' Willingness To Produce Alternative Biofuel Feedstocks, Andra Johnson, Charles Butler
Professional Agricultural Workers Journal
Abstract
The study assessed the willingness of small and medium-sized farmers to produce alternative biofuel crops in Louisiana and Mississippi. Data were collected from a random sample of 304 participants. The results revealed that the majority of the respondents were males, African Americans, over 50 years, part-time farmers, and a third earned less than $1,000 per year from farming. Most of the respondents (75%) indicated an interest in alternative fuel development, and 72% do not use alternative fuels in their operations. Also, a majority of respondents (83%) indicated that they would like to learn more about opportunities for alternative fuel …
An Analysis Of The Characteristics And Practices Of Selected Alabama Small Livestock Producers: A Focus On Economics And Marketing, Jannette R. Bartlett, Nii O. Tackie, Mst Nusrat Jahan, Akua Adu-Gyamfi
An Analysis Of The Characteristics And Practices Of Selected Alabama Small Livestock Producers: A Focus On Economics And Marketing, Jannette R. Bartlett, Nii O. Tackie, Mst Nusrat Jahan, Akua Adu-Gyamfi
Professional Agricultural Workers Journal
Abstract
The study examined the characteristics and practices of small livestock producers, focusing on economics and marketing. Data were obtained from a convenience sample of 121 small producers from several South Central Alabama counties, and were analyzed using descriptive statistics, including chi-square tests. The socioeconomic characteristics reflected a higher proportion of part-time farmers; a higher proportion with at most a two-year/technical degree or some college education; and a higher proportion with $40,000 or less annual household income. A majority had been farming more than thirty years, and most had small herds. Also, very few made profits; many sold animals live …
Screening Of Olive Cultivars For Tolerance To Fusicladium Oleagineum In South Africa, Zakhele Cyril Msimango
Screening Of Olive Cultivars For Tolerance To Fusicladium Oleagineum In South Africa, Zakhele Cyril Msimango
Professional Agricultural Workers Journal
Abstract
This study evaluated commercial olive cultivars for resistance to olive leaf spot (OLS). A growth chamber trial was undertaken with one temperature treatment (16°C) applied during inoculation while a relative humidity (RH) of above 80% was maintained. Plants were kept for 48 hours at 99% RH after inoculation and then moved to shade netted area for disease development at a temperature of 25±5°C. The results were used for categorizing the eight olive cultivars evaluated in this study according to their OLS susceptibility. ‘Frantoio’ was categorized as most tolerant; ‘Nandi’ and ‘Leccino’ were found to be moderately tolerant, and ‘Nocellara …
Odu's Ray Toll To Discuss Sea Level Rise On 'With Good Reason', Publicaffairs & Newsbureau, Old Dominion University
Odu's Ray Toll To Discuss Sea Level Rise On 'With Good Reason', Publicaffairs & Newsbureau, Old Dominion University
News Items
No abstract provided.
Interactions Between Thiourea And Imines. Prelude To Catalysis, Vincent De Paul Nzuwah-Nziko, Steve Scheiner
Interactions Between Thiourea And Imines. Prelude To Catalysis, Vincent De Paul Nzuwah-Nziko, Steve Scheiner
Chemistry and Biochemistry Faculty Publications
The interaction between thiourea and a series of imines was examined via high-level ab initio calculations. For each imine, there is a set of stable complexes that represent minima on the potential energy surface. One type is characterized by a pair of symmetric NH···N hydrogen bonds (HBs), with both NH groups of thiourea approaching the imine N from above and below its molecular plane. Another geometry category combines a linear NH···N with a CH···S HB. A third, which is less stable, has the S approaching the imine’s CH2 group, and a stacking arrangement is present in the fourth. Interaction energies …
Polystyrene Formation On Monolayer-Modified Nitinol Effectively Controls Corrosion, Rosalynn Quiñones-Fernández, Ellen Gawalt
Polystyrene Formation On Monolayer-Modified Nitinol Effectively Controls Corrosion, Rosalynn Quiñones-Fernández, Ellen Gawalt
Rosalynn Quiñones-Fernández
A surface-initiated polymerization of styrene on carboxylic acid terminated phosphonic monolayers was utilized to increase the corrosion resistance of nitinol and nickel oxide surfaces. Alkyl chain ordering, organic reactions, wettability, and film quality of the monolayers and polymers were determined by infrared spectroscopy, atomic force microscopy, matrix-assisted laser desorption ionization spectrometry, and water contact angles. The polystyrene film proved to be a better corrosion barrier than phosphonic acid monolayers by analysis with cyclic voltammetry and electrochemical impedance spectroscopy. The protection efficiency of the polystyrene film on nitinol was 99.4% and the monolayer was 42%.
Structural And Physicochemical Aspects Of Dasatinib Hydrate And Anhydrate Phases, Saikat Roy, Rosalynn Quiñones
Structural And Physicochemical Aspects Of Dasatinib Hydrate And Anhydrate Phases, Saikat Roy, Rosalynn Quiñones
Rosalynn Quiñones-Fernández
Crystal structures for the commercial monohydrate form and an anhydrate form of dasatinib, an oral anti-cancer agent, are presented along with characterization by Raman spectroscopy, powder X-ray diffraction, differential scanning calorimetry, and thermogravimetric analysis. Solubility measurements conducted in water reveal the anhydrate has dramatically improved solubility compared to the commercial hydrate form. Finally, dasatinib is a rare example of a promiscuous solvate former and the basis for this behavior can now be understood by examining the poor packing efficiency in the unsolvated form.
Life As An Nfl Statistician, Dennis Lock
Life As An Nfl Statistician, Dennis Lock
Mathematics Colloquium Series
Over the last few years, the fields of statistics and mathematics have become more prevalent and popular in professional sports (with the help of mainstream books and movies like Moneyball). The use of advanced (and non-advanced) statistical methods is growing across the sporting landscape from the front office to the media, and even into business and ticket sales. This talk will discuss Lock’s experiences building an analytics department with the Miami Dolphins as well as the general role of statistics in sports today. It will also including the recent analytics boom in the front office framework, the coinciding need for …
Enhancing Manufacturing Planning And Control Systems Through Artificial Intelligence Techniques, Ronald S. Dattero, John J. Kanet, Edna M. White
Enhancing Manufacturing Planning And Control Systems Through Artificial Intelligence Techniques, Ronald S. Dattero, John J. Kanet, Edna M. White
John J. Kanet
Manufacturing planning and control systems are currently dominated by systems based upon Material Requirements Planning (MRP). MRP systems have a number of fundamental flaws. A potential alternative to MRP systems is suggested after research into the economic batch scheduling problem. Based on the ideas of economic batch scheduling, and enhanced through artificial intelligence techniques, an alternative approach to manufacturing planning and control is developed. A framework for future research on this alternative to MRP is presented.
Production Planning And Control Systems-State Of The Art And New Directions, V. Sridharan, John Kanet
Production Planning And Control Systems-State Of The Art And New Directions, V. Sridharan, John Kanet
John J. Kanet
This chapter begins with a description of the role of production planning and control (PPC) within the manufacturing function. After discussing the impact of the operating environment on the choice a system for PPC, we describe some recent empirical evidence regarding the use and performance results of various PPC systems. This is followed by a brief overview of the two most widely used systems for production planning and control. We then describe a recent development in the area of short-term detailed scheduling exploiting the latest developments in computing technology. The chapter concludes with a discussion of an emerging paradigm for …
Operations Research For Freight Train Routing And Scheduling, Steven Harrod, Michael Gorman
Operations Research For Freight Train Routing And Scheduling, Steven Harrod, Michael Gorman
Michael F. Gorman
This article describes the service design activities that plan and implement the rail freight operating plan. Elements of strategic service design include the setting of train frequency, the routing of cars among trains, and the consolidation of cars, called blocking. At the operational level, trains are dispatched either according to train paths configured in advance, called timetables, or according to priority rules. We describe the North American and European practice along with selected modeling and problem solving methodologies appropriate for each of the operating conditions described.
Operations Research Approaches In Asset Management In Freight Rail, Michael Gorman, Steven Harrod
Operations Research Approaches In Asset Management In Freight Rail, Michael Gorman, Steven Harrod
Michael F. Gorman
This article describes operations research methodologies as they apply to asset management in freight rail. We describe state-of-the-art methods for locomotive, crew, rail-car, line and yard planning and management. We conclude with emerging areas of research in rail.
The Firece Green Fire: Vol. 6 Issue 3, Wofford College Environmental Studies Program
The Firece Green Fire: Vol. 6 Issue 3, Wofford College Environmental Studies Program
The Fierce Green Fire
No abstract provided.
Prediction Of 1‑Octanol Solubilities Using Data From The Open Notebook Science Challenge, Andrew Lang, Michael A. Buonaiuto
Prediction Of 1‑Octanol Solubilities Using Data From The Open Notebook Science Challenge, Andrew Lang, Michael A. Buonaiuto
College of Science and Engineering Faculty Research and Scholarship
Background: 1-Octanol solubility is important in a variety of applications involving pharmacology and environmental chemistry. Current models are linear in nature and often require foreknowledge of either melting point or aqueous solubility. Here we extend the range of applicability of 1-octanol solubility models by creating a random forest model that can predict 1-octanol solubilities directly from structure. Results: We created a random forest model using CDK descriptors that has an out-of-bag (OOB) R2 value of 0.66 and an OOB mean squared error of 0.34. The model has been deployed for general use as a Shiny application. Conclusion: The 1-octanol solubility …
Tidal Flat Morphodynamics: A Synthesis, C. T. Friedrichs
Tidal Flat Morphodynamics: A Synthesis, C. T. Friedrichs
Presentations
No abstract provided.
Rapid Biotic Homogenization Of Marine Fish Assemblages, Anne E. Magurran, Maria Dornelas, Faye Moyes, Nicholas J. Gotelli, Brian Mcgill
Rapid Biotic Homogenization Of Marine Fish Assemblages, Anne E. Magurran, Maria Dornelas, Faye Moyes, Nicholas J. Gotelli, Brian Mcgill
College of Arts and Sciences Faculty Publications
The role human activities play in reshaping biodiversity is increasingly apparent in terrestrial ecosystems. However, the responses of entire marine assemblages are not well-understood, in part, because few monitoring programs incorporate both spatial and temporal replication. Here, we analyse an exceptionally comprehensive 29-year time series of North Atlantic groundfish assemblages monitored over 5° latitude to the west of Scotland. These fish assemblages show no systematic change in species richness through time, but steady change in species composition, leading to an increase in spatial homogenization: the species identity of colder northern localities increasingly resembles that of warmer southern localities. This biotic …
Transmission Of Light In Nano-Hole Metamaterial, Shankaranandh Balakrishnan .
Transmission Of Light In Nano-Hole Metamaterial, Shankaranandh Balakrishnan .
Electronic Thesis and Dissertation Repository
The interaction of light with metallic nano-hole array structures enable excitation of surface plasmon polaritons at any angle of incidence. Nano-hole array structure can transmit more radiation than incident light due to the presence of surface plasmon polaritons. This phenomenon has opened up possibilities for a wide range of applications such as Surface Plasmon Resonance sensing and Surface Enhanced Raman spectroscopy. In this thesis, quantum scattering theory and quantum density matrix method are employed to assess optical transmission of metallic nano-hole array structures. The scattering cross section spectrum is calculated for nano-hole array structures with different nano-hole radii and periodicities …
Does Gender Matter? Human Elephant Conflict In Sri Lanka: A Gendered Analysis Of Human Elephant Conflict And Natural Resource Management In A Rural Sri Lankan Village, Katherine Eileen Griffin
Does Gender Matter? Human Elephant Conflict In Sri Lanka: A Gendered Analysis Of Human Elephant Conflict And Natural Resource Management In A Rural Sri Lankan Village, Katherine Eileen Griffin
Dissertations and Theses
This study is a gendered analysis of natural resource management at the local scale of a poor rural Sri Lankan village in a conservation buffer zone. This village experiences destruction of forests and human elephant conflict. The objective of this study is to gain an in-depth knowledge of residents' use and understandings of environmental resources, and to investigate if gender helps shape these factors. This study relies on a social sustainability conceptual framework. It tracks participation of local women and men in natural resource management, and in conservation within and outside of the Bibile community. Local nongovernmental organizations focus on …
Form Domains And Eigenfunction Expansions For Differential Equations With Eigenparameter Dependent Boundary Conditions, Branko Ćurgus, Paul Binding
Form Domains And Eigenfunction Expansions For Differential Equations With Eigenparameter Dependent Boundary Conditions, Branko Ćurgus, Paul Binding
Branko Ćurgus
Form domains are characterized for regular 2n-th order differential equations subject to general self-adjoint boundary conditions depending affinely on the eigenparameter. Corresponding modes of convergence for eigenfunction expansions are studied, including uniform convergence of the first n - 1 derivatives.
A Nonlinear Filter For Markov Chains And Its Effect On Diffusion Maps, Stefan Steinerberger
A Nonlinear Filter For Markov Chains And Its Effect On Diffusion Maps, Stefan Steinerberger
Yale Day of Data
Diffusion maps are a modern mathematical tool that helps to find structure in large data sets - we present a new filtering technique that is based on the assumption that errors in the data are intrinsically random to isolate and filter errors and thus boost the efficiency of diffusion maps. Applications include data sets from medicine (the Cleveland Heart Disease Data set and the Wisconsin Breast Cancer Data set) and engineering (the Ionosphere data set).
Crowdsourcing Global Wastewater Data, Don Mosteller, Sam Cohen, Cory Nestor, Angel Hsu, Omar Malik
Crowdsourcing Global Wastewater Data, Don Mosteller, Sam Cohen, Cory Nestor, Angel Hsu, Omar Malik
Yale Day of Data
No time to waste: Crowdsourcing global wastewater treatment data
Worldwide, over 80 percent of wastewater is discharged into water bodies without undergoing treatment, severely impairing human well-being and ecosystem vitality along the way. National performance on wastewater treatment is difficult to quantify and is poorly understood due to a lack of common definitions, poor data collection standards, and limited historical data. To address this, the Yale Environmental Performance Index (EPI), a research group that produces a biennial ranking of country-level environmental performance, developed a first-of-its kind national wastewater treatment indicator.[1]
The indicator assesses wastewater treatment performance for 183 countries, …
A Machine Learning Approach To Post-Market Surveillance Of Medical Devices, Jonathan Bates, Shu-Xia Li, Craig Parzynski, Ronald Coifman, Harlan Krumholz, Joseph Ross
A Machine Learning Approach To Post-Market Surveillance Of Medical Devices, Jonathan Bates, Shu-Xia Li, Craig Parzynski, Ronald Coifman, Harlan Krumholz, Joseph Ross
Yale Day of Data
Post-market surveillance is a collection of processes and activities used by product manufacturers and regulators, such as the U.S. Food and Drug Administration (FDA) to monitor the safety and effectiveness of medical devices once they are available for use “on the market”. These activities are designed to generate information to identify poorly performing devices and other safety problems, accurately characterize real-world device performance and clinical outcomes, and facilitate the development of new devices, or new uses for existing devices. Typically, a device is monitored by comparing adverse events in the exposed population to a matched unexposed population. This research considers …
K-Mer Analysis On Developmental And Housekeeping Enhancer Peaks, Yunsi Yang, Anurag Sethi, Mark Gerstein
K-Mer Analysis On Developmental And Housekeeping Enhancer Peaks, Yunsi Yang, Anurag Sethi, Mark Gerstein
Yale Day of Data
The regulation of gene expression involves interaction between transcriptional enhancers and core promoters. However, the separation between developmental and housekeeping gene regulation remains unknown. Here, we present a method to detect if different core promoters exhibit specificity to certain enhancers within massively parallel assays for enhancer detection. We use k-mers of various length (3-8bp) as sequence features and compare k-mer frequencies between developmental and housekeeping enhancers. This method shows promoter specificity of enhancers in D. melanogaster.
A Self-Assembled, Low-Cost, Microstructured Layer For Extremely Stretchable Gold Films, Tricia Carmichael, Heather L. Filiatrault, R. Stephen Carmichael, Rachel A. Boutette
A Self-Assembled, Low-Cost, Microstructured Layer For Extremely Stretchable Gold Films, Tricia Carmichael, Heather L. Filiatrault, R. Stephen Carmichael, Rachel A. Boutette
Chemistry and Biochemistry Publications
We demonstrate a simple, low-cost, and green approach to deposit a microstructured coating on the silicone elastomer polydimethylsiloxane (PDMS) that can be coated with gold to produce highly stretchable and conductive films. The microstructured coating is fabricated using an aqueous emulsion of poly(vinyl acetate) (PVAc): common, commercially available white glue. The aqueous glue emulsion self-assembles on the PDMS surface to generate clustered PVAc globules, which can be conformally coated with gold. The microstructured surface provides numerous defect sites that localize strain when the structure is stretched, resulting in the initiation of numerous microcracks. As the structure is further elongated, the …
Assessing Student Reasoning In Upper-Division Electricity And Magnetism At Oregon State University, Justyna P. Zwolak, Corinne A. Manogue
Assessing Student Reasoning In Upper-Division Electricity And Magnetism At Oregon State University, Justyna P. Zwolak, Corinne A. Manogue
Stem Transformation Institute
[This paper is part of the Focused Collection on Upper Division Physics Courses.] Standardized assessment tests that allow researchers to compare the performance of students under various curricula are highly desirable. There are several research-based conceptual tests that serve as instruments to assess and identify students’ difficulties in lower-division courses. At the upper-division level assessing students’ difficulties is a more challenging task. Although several research groups are currently working on such tests, their reliability and validity are still under investigation. We analyze the results of the Colorado Upper-Division Electrostatics diagnostic from Oregon State University and compare it with data from …
Student Understanding Of The Boltzmann Factor, Trevor I. Smith, Donald B. Mountcastle, John R. Thompson
Student Understanding Of The Boltzmann Factor, Trevor I. Smith, Donald B. Mountcastle, John R. Thompson
Physics and Astronomy Faculty Scholarship
We present results of our investigation into student understanding of the physical significance and utility of the Boltzmann factor in several simple models. We identify various justifications, both correct and incorrect, that students use when answering written questions that require application of the Boltzmann factor. Results from written data as well as teaching interviews suggest that many students can neither recognize situations in which the Boltzmann factor is applicable nor articulate the physical significance of the Boltzmann factor as an expression for multiplicity, a fundamental quantity of statistical mechanics. The specific student difficulties seen in the written data led us …
Identifying Student Difficulties With Heat Engines, Entropy, And The Carnot Cycle, Trevor I. Smith, Warren M. Christensen, Donald B. Mountcastle, John R. Thompson
Identifying Student Difficulties With Heat Engines, Entropy, And The Carnot Cycle, Trevor I. Smith, Warren M. Christensen, Donald B. Mountcastle, John R. Thompson
Physics and Astronomy Faculty Scholarship
We report on several specific student difficulties regarding the second law of thermodynamics in the context of heat engines within upper-division undergraduate thermal physics courses. Data come from ungraded written surveys, graded homework assignments, and videotaped classroom observations of tutorial activities. Written data show that students in these courses do not clearly articulate the connection between the Carnot cycle and the second law after lecture instruction. This result is consistent both within and across student populations. Observation data provide evidence for myriad difficulties related to entropy and heat engines, including students’ struggles in reasoning about situations that are physically impossible …
Addressing Confounding In Predictive Models With An Application To Neuroimaging, Kristin A. Linn, Bilwaj Gaonkar, Jimit Doshi, Christos Davatzikos, Russell T. Shinohara
Addressing Confounding In Predictive Models With An Application To Neuroimaging, Kristin A. Linn, Bilwaj Gaonkar, Jimit Doshi, Christos Davatzikos, Russell T. Shinohara
UPenn Biostatistics Working Papers
Understanding structural changes in the brain that are caused by a particular disease is a major goal of neuroimaging research. Multivariate pattern analysis (MVPA) comprises a collection of tools that can be used to understand complex disease effects across the brain. We discuss several important issues that must be considered when analyzing data from neuroimaging studies using MVPA. In particular, we focus on the consequences of confounding by non-imaging variables such as age and sex on the results of MVPA. After reviewing current practice to address confounding in neuroimaging studies, we propose an alternative approach based on inverse probability weighting. …
Control-Group Feature Normalization For Multivariate Pattern Analysis Using The Support Vector Machine, Kristin A. Linn, Bilwaj Gaonkar, Jimit Doshi, Christos Davatzikos, Russell T. Shinohara
Control-Group Feature Normalization For Multivariate Pattern Analysis Using The Support Vector Machine, Kristin A. Linn, Bilwaj Gaonkar, Jimit Doshi, Christos Davatzikos, Russell T. Shinohara
UPenn Biostatistics Working Papers
Normalization of feature vector values is a common practice in machine learning. Generally, each feature value is standardized to the unit hypercube or by normalizing to zero mean and unit variance. Classification decisions based on support vector machines (SVMs) or by other methods are sensitive to the specific normalization used on the features. In the context of multivariate pattern analysis using neuroimaging data, standardization effectively up- and down-weights features based on their individual variability. Since the standard approach uses the entire data set to guide the normalization it utilizes the total variability of these features. This total variation is inevitably …
Evaluation Of Anisole-Substituted Boron Difluoride Formazanate Complexes For Fluorescence Cell Imaging, Ryan R. Maar, Stephanie M. Barbon, Neha Sharma, Hilary Groom, Leonard G. Luyt, Joe Gilroy
Evaluation Of Anisole-Substituted Boron Difluoride Formazanate Complexes For Fluorescence Cell Imaging, Ryan R. Maar, Stephanie M. Barbon, Neha Sharma, Hilary Groom, Leonard G. Luyt, Joe Gilroy
Chemistry Publications
The evaluation of three subclasses of boron difluoride formazanate complexes bearing o-, m-, and p-anisole N-aryl substituents (Ar) as readily accessible alternatives to boron dipyrromethene (BODIPY) dyes for cell imaging applications is described. While the wavelengths of maximum absorption (lmax) and emission (lem) observed for each subclass of complexes, which differed by their carbon-bound substituents (R), were similar, the emission quantum yields for 7a-c (R = cyano) were enhanced relative to 8a-c (R = nitro) and 9a-c (R = phenyl). Complexes 7a-c and 8a-c were also significantly …