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Photocatalytic Reaction of Gas-Phase Naphthalene on Paint- and Sunscreen-Coated Surfaces
Nicholas A. Ashley,Noelle McBride,Jason Krumholt,Breeana Baker
ISRN Chemical Engineering , 2012, DOI: 10.5402/2012/372479
Abstract:
Photocatalytic Reaction of Gas-Phase Naphthalene on Paint- and Sunscreen-Coated Surfaces
Nicholas A. Ashley,Noelle McBride,Jason Krumholt,Breeana Baker,Kalliat T. Valsaraj
ISRN Chemical Engineering , 2012, DOI: 10.5402/2012/372479
Abstract: The uses of metal oxide nanoparticles in modern paint and sunscreen formulations are widespread. Through materials characterization and kinetic experiments, it is demonstrated that fresh surface coatings of paint and sunscreen photocatalytically degrade gaseous naphthalene. The primary metal oxides are TiO2 in the form of the rutile phase in paint and as anatase in sunscreen formulations. Other metal oxides present are Al2O3 and ZnO. Several organic fillers that are photochemically active are also present in paint and sunscreen samples but are unidentified. Reaction rate constants increased with increasing air relative humidity, due to the production of surface hydroxyl radical, and decreased with increasing coating thickness, due to mass transfer limitations. Photocatalytic degradation on these freshly generated surfaces is observed to be fast, with naphthalene half-lives shorter than 30 minutes. This work demonstrates that large, semivolatile organic compounds can react photochemically on freshly generated paint- and sunscreen-coated surfaces and may impact air quality in both indoor and outdoor environments. 1. Introduction The widespread commercial use of nanotechnology has far-reaching environmental impacts and implications. Modern paint and sunscreen formulations contain large quantities of ultrafine metal oxide particles, often between 10 and 20 weight percent in paints, and up to 25 weight percent in sunscreens [1–4]. Micron-sized TiO2 has been used for many years as a UV absorber and pigmentary agent. The use of nanoscale metal oxides in these formulations dramatically increases the total number of particles and specific surface area relative to their micron-sized counterparts. Since some of these metal oxides are well-known photocatalysts, this can also dramatically increase their reactivity towards gas-phase pollutants. The photocatalytic degradation of small organic molecules, such as formaldehyde, methanol, and 2-propanol, on paint-coated surfaces or thin films containing embedded TiO2 nanoparticles has been studied [5–10]. To date, few studies have examined the destruction of large, semivolatile organic compounds (SVOCs) on paint films. Naphthalene is a representative SVOC. It is a common air pollutant, a byproduct of incomplete combustion of industrial processes, and is widespread [11]. Photocatalytic destruction of SVOCs is of particular importance since a variety of partial oxidation products further give rise to secondary organic aerosol (SOA) in air [12]. Some of the naphthalene partial oxidation products are known to be toxic, and
Sparse Representation by Frames with Signal Analysis  [PDF]
Christopher Baker
Journal of Signal and Information Processing (JSIP) , 2016, DOI: 10.4236/jsip.2016.71006
Abstract: The use of frames is analyzed in Compressed Sensing (CS) through proofs and experiments. First, a new generalized Dictionary-Restricted Isometry Property (D-RIP) sparsity bound constant for CS is established. Second, experiments with a tight frame to analyze sparsity and reconstruction quality using several signal and image types are shown. The constant \"\"？is used in fulfilling the definition of D-RIP. It is proved that k-sparse signals can be reconstructed if \"\"？by using a concise and transparent argument1. The approach could be extended to obtain other D-RIP bounds (i.e. \"\"). Experiments contrast results of a Gabor tight frame with Total Variation minimization. In cases of practical interest, the use of a Gabor dictionary performs well when achieving a highly sparse representation and poorly when this sparsity is not achieved.
Comparison of MRI Under-Sampling Techniques for Compressed Sensing with Translation Invariant Wavelets Using FastTestCS: A Flexible Simulation Tool  [PDF]
Christopher Baker
Journal of Signal and Information Processing (JSIP) , 2016, DOI: 10.4236/jsip.2016.74021
Abstract: A sparsifying transform for use in Compressed Sensing (CS) is a vital piece of image reconstruction for Magnetic Resonance Imaging (MRI). Previously, Translation Invariant Wavelet Transforms (TIWT) have been shown to perform exceedingly well in CS by reducing repetitive line pattern image artifacts that may be observed when using orthogonal wavelets. To further establish its validity as a good sparsifying transform, the TIWT is comprehensively investigated and compared with Total Variation (TV), using six under-sampling patterns through simulation. Both trajectory and random mask based under-sampling of MRI data are reconstructed to demonstrate a comprehensive coverage of tests. Notably, the TIWT in CS reconstruction performs well for all varieties of under-sampling patterns tested, even for cases where TV does not improve the mean squared error. This improved Image Quality (IQ) gives confidence in applying this transform to more CS applications which will contribute to an even greater speed-up of a CS MRI scan. High vs low resolution time of flight MRI CS re-constructions are also analyzed showing how partial Fourier acquisitions must be carefully addressed in CS to prevent loss of IQ. In the spirit of reproducible research, novel software is introduced here as FastTestCS. It is a helpful tool to quickly develop and perform tests with many CS customizations. Easy integration and testing for the TIWT and TV \"\" minimization are exemplified. Simulations of 3D MRI datasets are shown to be efficiently distributed as a scalable solution for large studies. Comparisons in reconstruction computation time are made between the Wavelab toolbox and Gnu Scientific Library in FastTestCS that show a significant time savings factor of 60×. The addition of FastTestCS is proven to be a fast, flexible, portable and reproducible simulation aid for CS research.
Application of High-Frequency Gravitational Waves to the Cataclysmic Event of Our First Encounter with Intelligent Extraterrestrial Beings  [PDF]
Robert M. L. Baker, Bonnie Sue Baker
Journal of Applied Mathematics and Physics (JAMP) , 2016, DOI: 10.4236/jamp.2016.41015
Abstract: Three advances are proposed as a pathway to the cataclysmic event of our first encounter with intelligent extraterrestrial beings. First, discovery of very large numbers of extraterrestrial planets, “exoplanets” (possibly as many as1023 in our Universe); second, introduction of electronic components into the human body evolving into a cybernetic and biological “cyborg,” a model for an extraterrestrial being Cyborgs might allow advanced civilizations to endure hundreds of thousands of years. Third, the recent development of high-frequency gravitational wave (HFGW) detectors, the communication means of choice for an advanced cyborg civilization since they are not easily absorbed like electromagnetic radiation. Six HFGW detectors are presented for application to our first encounter with intelligent extraterrestrial beings. Numerical estimates are made for the failure of extraterrestrial civilizations such that no two exist at the same time (Fermi’s Paradox). It is concluded that there might remain at least ≈1.48 × 108 Worlds intercommunicating with HFGWs at any one time in any one region of our Universe. The predicted form of extraterrestrial beings is by means of animaginary, but based upon comprehensively documented and detailed projection of the evolution of “Earthling” homosapiens, to become “cyborgs.” It is proposed that such long-living cyborg forms of intelligent beings would be encountered by us. The first cataclysmic encounter with them is expected to be interception of their interstellar communications. The predicted frequency of intercepted messages under one set of assumptions is at least 1500 per day. After decoding the intercepted messages, keys may be found to improve vastly the present and future quality of life for us earthlings. Advanced beings might utilize direct brain-to-brain communication and it is concluded that research into brain-to-brain communication and HFGW detection are encouraged.
Impact of Freeze-thaw Cycles and Storage Time on Plasma Samples Used in Mass Spectrometry Based Biomarker Discovery Projects
Breeana L Mitchell,Yutaka Yasui,Christopher I Li,Annette L. Fitzpatrick
Cancer Informatics , 2005,
Abstract: : Mass spectrometry approaches to biomarker discovery in human fluids have received a great deal of attention in recent years. While mass spectrometry instrumentation and analysis approaches have been widely investigated, little attention has been paid to how sample handling can impact the plasma proteome and therefore influence biomarker discovery. We have investigated the effects of two main aspects of sample handling on MALDI-TOF data: repeated freeze-thaw cycles and the effects of long-term storage of plasma at -70°C. Repeated freeze-thaw cycles resulted in a trend towards increasing changes in peak intensity, particularly after two thaws. However, a 4-year difference in long-term storage appears to have minimal effect on protein in plasma as no differences in peak number, mass distribution, or coefficient of variation were found between samples. Therefore, limiting freeze/thaw cycles seems more important to maintaining the integrity of the plasma proteome than degradation caused by long-term storage at -70°C.
Use of Science in Autism Policy Development  [PDF]
Dana Lee Baker
Open Journal of Political Science (OJPS) , 2013, DOI: 10.4236/ojps.2013.31001
Abstract:

Though ultimately beneficial to society, interactions between science and politics require careful tending. Because science is an exercise in trial and error, public policy development can be affected by both scientific missteps and the length of time it takes to produce reasonable scientific certainty. Introduction of scientific findings, especially more preliminary ones, into the political process has a mixed record. Understanding how these tensions play out in contemporary politics is important for both disability studies and policy studies generally. This article explores how science and scientific evidence is employed by stakeholders engaged with autism policy development in the United States.

E-Learning Optimization Using Supervised Artificial Neural-Network  [PDF]
Mohamed Sayed, Faris Baker
Journal of Software Engineering and Applications (JSEA) , 2015, DOI: 10.4236/jsea.2015.81004
Abstract: Improving learning outcome has always been an important motivating factor in educational inquiry. In a blended learning environment where e-learning and traditional face to face class tutoring are combined, there are opportunities to explore the role of technology in improving student’s grades. A student’s performance is impacted by many factors such as engagement, self-regulation, peer interaction, tutor’s experience and tutors’ time involvement with students. Furthermore, e-course design factors such as providing personalized learning are an urgent requirement for improved learning process. In this paper, an artificial neural network model is introduced as a type of supervised learning, meaning that the network is provided with example input parameters of learning and the desired optimized and correct output for that input. We also describe, by utilizing e-learning interactions and social analytics how to use artificial neural network to produce a converging mathematical model. Then students’ performance can be efficiently predicted and so the danger of failing in an enrolled e-course should be reduced.
Geographical Analysis of Lung Cancer Mortality Rate and PM2.5 Using Global Annual Average PM2.5 Grids from MODIS and MISR Aerosol Optical Depth  [PDF]
Zhiyong Hu, Ethan Baker
Journal of Geoscience and Environment Protection (GEP) , 2017, DOI: 10.4236/gep.2017.56017
Abstract:
Exposure to particulate matter with an aerodynamic diameter of less than 2.5 μm (PM2.5) may increase risk of lung cancer. The repetitive and broad-area coverage of satellites may allow atmospheric remote sensing to offer a unique opportunity to monitor air quality and help fill air pollution data gaps that hinder efforts to study air pollution and protect public health. This geographical study explores if there is an association between PM2.5 and lung cancer mortality rate in the conterminous USA. Lung cancer (ICD-10 codes C34- C34) death count and population at risk by county were extracted for the period from 2001 to 2010 from the U.S. CDC WONDER online database. The 2001-2010 Global Annual Average PM2.5 Grids from MODIS and MISR Aerosol Optical Depth dataset was used to calculate a 10 year average PM2.5 pollution. Exploratory spatial data analyses, spatial regression (a spatial lag and a spatial error model), and spatially extended Bayesian Monte Carlo Markov Chain simulation found that there is a significant positive association between lung cancer mortality rate and PM2.5. The association would justify the need of further toxicological investigation of the biological mechanism of the adverse effect of the PM2.5 pollution on lung cancer. The Global Annual Average PM2.5 Grids from MODIS and MISR Aerosol Optical Depth dataset provides a continuous surface of concentrations of PM2.5 and is a useful data source for environmental health research.
Synthesis of Some New Thioethers and 4-Thiazolidinones Bearing 3-(Pyridine-4'-yl)-1,2,4-Triazino[5,6-b]Indole Moiety as Antifungal Agents  [PDF]
Wafa A. Baker Bawazir
International Journal of Organic Chemistry (IJOC) , 2019, DOI: 10.4236/ijoc.2019.91004
Abstract: Some new asymmetric thioethers 5 and 4-thiazolidinones 6 have been obtained from condensation of 5-formyl-3-(pyridin-4'-yl)-1,2,4-triazino[5,6-b] indole (3) with halogenated aromatic amines followed by addition of thiophenol and/or cycloaddition with thiolactic acids in nonpolar solvents. Structures of the products confirmed by elemental analysis and spectral measurements. The new systems obtained were evaluated as antifungal agents.
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