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174,913 full-text articles. Page 7 of 4535.

De-Icers: What Is Safe For The Environment And Is Effective?, Dylan Walker 2018 Fort Richmond Collegiate

De-Icers: What Is Safe For The Environment And Is Effective?, Dylan Walker

The International Student Science Fair 2018

The purpose of this experiment was to determine the affect that various de-icers (both organic and inorganic based) had on the health of grass, as well as determine the efficiency of the de-icer in melting ice to then compare and contrast the data to find the best overall de-icer in terms of effectiveness and environmental impact.


Light, Electricity And Semiconductors, Josephine Zhao 2018 Fort Richmond Collegiate

Light, Electricity And Semiconductors, Josephine Zhao

The International Student Science Fair 2018

No abstract provided.


Aftershocks In Slowly Compressed Bulk Metallic Glasses: Experiments And Theory, Louis W. McFaul, Wendelin Wright, Xiaojun Gu, Jonathan T. Uhl, Karin A. Dahmen 2018 University of Illinois at Urbana-Champaign

Aftershocks In Slowly Compressed Bulk Metallic Glasses: Experiments And Theory, Louis W. Mcfaul, Wendelin Wright, Xiaojun Gu, Jonathan T. Uhl, Karin A. Dahmen

Faculty Journal Articles

We observe two distinct interevent time patterns in the slip avalanches of compressed bulk metallic glasses (BMGs). Small slip avalanches cluster together in time, but large slip avalanches recur roughly periodically. We compare the timing patterns of BMG slip avalanches with timing patterns of earthquakes and with the predictions of a mean-field model. The time clustering of small avalanches is similar to the known time clustering of earthquake foreshocks and aftershocks.


The Study Design Elements Employed By Researchers In Preclinical Animal Experiments From Two Research Domains And Implications For Automation Of Systematic Reviews, Annette M. O'Connor, Sarah C. Totton, Jonah C. Cullen, Mahmood Ramezani, Vijay Kalivarapu, Chaohui Yuan, Stephen B. Gilbert 2018 Iowa State University

The Study Design Elements Employed By Researchers In Preclinical Animal Experiments From Two Research Domains And Implications For Automation Of Systematic Reviews, Annette M. O'Connor, Sarah C. Totton, Jonah C. Cullen, Mahmood Ramezani, Vijay Kalivarapu, Chaohui Yuan, Stephen B. Gilbert

Veterinary Diagnostic and Production Animal Medicine Publications

Systematic reviews are increasingly using data from preclinical animal experiments in evidence networks. Further, there are ever-increasing efforts to automate aspects of the systematic review process. When assessing systematic bias and unit-of-analysis errors in preclinical experiments, it is critical to understand the study design elements employed by investigators. Such information can also inform prioritization of automation efforts that allow the identification of the most common issues. The aim of this study was to identify the design elements used by investigators in preclinical research in order to inform unique aspects of assessment of bias and error in preclinical research. Using 100 ...


The Impact Of The Deepwater Horizon Blowout On Historic Shipwreck-Associated Sediment Microbiomes In The Northern Gulf Of Mexico, Leila J. Hamdan, Jennifer Salerno, Allen H. Reed, Samantha B. Joye, Melanie Damour 2018 University of Southern Mississippi

The Impact Of The Deepwater Horizon Blowout On Historic Shipwreck-Associated Sediment Microbiomes In The Northern Gulf Of Mexico, Leila J. Hamdan, Jennifer Salerno, Allen H. Reed, Samantha B. Joye, Melanie Damour

Faculty Publications

More than 2,000 historic shipwrecks spanning 500 years of history, rest on the Gulf of Mexico seafloor. Shipwrecks serve as artificial reefs and hotspots of biodiversity by providing hard substrate, something rare in deep ocean regions. The Deepwater Horizon (DWH) spill discharged crude oil into the deep Gulf. Because of physical, biological, and chemical interactions, DWH oil was deposited on the seafloor, where historic shipwrecks are present. This study examined sediment microbiomes at seven historic shipwrecks. Steel-hulled, World War II-era shipwrecks and wooden-hulled, 19th century shipwrecks within and outside of the surface oiled area and subsurface plume were examined ...


An Evaluation Of The Utility Of A Mass-Weighted Frequency Distribution Of Sediment For Modeling Aeolian Transport Rates, Raihan Jamil 2018 Louisiana State University

An Evaluation Of The Utility Of A Mass-Weighted Frequency Distribution Of Sediment For Modeling Aeolian Transport Rates, Raihan Jamil

LSU Master's Theses

Predictions made by aeolian transport models often do not match well with measured data. The poor predictive capability of these models remains a fundamental problem in aeolian geomorphology. This study evaluates the effectiveness of the recently proposed mass-weighted frequency distribution (Edwards and Namikas 2015) and the apparent von Kármán parameter proposed by Li et al. (2010) to improve transport rate predictions. The evaluation consists of comparisons of predicted transport rates versus a large dataset of measured field and lab transport rates collected from the literature. The transport rate predictions are made both with and without recalibration of model empirical coefficients ...


Probing Molecular Dynamics With Hyperpolarized Ultrafast Laplace Nmr Using A Low-Field, Singlesided Magnet†, Jared N. King, Alfredo Fallorina, Justin Yu, Guannan Zhang, Ville-Veikko Telkki, Christian Hilty, Tyler Meldrum 2018 College of William and Mary

Probing Molecular Dynamics With Hyperpolarized Ultrafast Laplace Nmr Using A Low-Field, Singlesided Magnet†, Jared N. King, Alfredo Fallorina, Justin Yu, Guannan Zhang, Ville-Veikko Telkki, Christian Hilty, Tyler Meldrum

Chemistry Faculty and Graduate Publications

Laplace NMR (LNMR) offers deep insights on diffusional and rotational motion of molecules. The so-called “ultrafast” approach, based on spatial data encoding, enables one to carry out a multidimensional LNMR experiment in a single scan, providing from 10 to 1000-fold acceleration of the experiment. Here, we demonstrate the feasibility of ultrafast diffusion–T2 relaxation correlation (DT2) measurements with a mobile, low-field, relatively low-cost, single-sided NMR magnet. We show that the method can probe a broad range of diffusion coefficients (at least from 10−8 to 10−12 m2 s−1) and reveal multiple components of fluids ...


Low Resolution Hi Imaging Of The Shield Galaxies, Masao L. Miazzo 2018 Macalester College

Low Resolution Hi Imaging Of The Shield Galaxies, Masao L. Miazzo

Macalester Journal of Physics and Astronomy

We present low-resolution Karl G. Jansky Very Large Array D-configuration HI spectral line observations of 32 previously unobserved local-volume low-mass dwarf galaxies in the Survey of HI in Extremely Low-mass Dwarfs (SHIELD). SHIELD was designed to probe the physical characteristics of the objects that inhabit the faint end of the HI mass function as populated by the ALFALFA blind HI extragalactic survey. These low angular-resolution images localize the HI-gas and provide the first glimpse of the neutral interstellar medium in these sources. We quantify the total HI mass of each system, and, using SDSS imaging, we compare the HI and ...


Actinometry Of Hydrogen Plasmas, A. M. Cotter, James Doyle 2018 Macalester College

Actinometry Of Hydrogen Plasmas, A. M. Cotter, James Doyle

Macalester Journal of Physics and Astronomy

Optical emission spectroscopy (OES) can be used to map the electron energy distribution of hydrogen plasmas. Using actinometry, a type of OES where trace amounts of noble gases are introduced, the effect of discharge power on the electron temperature of hydrogen plasmas was explored. This was done using argon and krypton as actinometers for low pressure hydrogen plasmas. It was determined that the electron temperature decreased with respect to power supplied to the discharge.


Modeling Recombination In Solar Cells, Paul Chery 2018 Macalester College

Modeling Recombination In Solar Cells, Paul Chery

Macalester Journal of Physics and Astronomy

Solar cells are a competitive alternative to nonrenewable energy sources such as fossil fuels. However, the efficiency of these devices is limited by photogenerated carrier recombination. We use a finite difference numerical model to study recombination phenomena in the absorber layer of solar cells including alternate recombination models and the effects of spatial distribution of recombination centers. We compare the effect of using the constant lifetime approximation for recombination to the full Shockley-Read-Hall expression in Silicon solar cells and find that the constant lifetime approximation holds for high defect densities but not for high photon flux densities. Finally, we simulate ...


Teaching Apportionment, Charles M. Biles 2018 Humboldt State University

Teaching Apportionment, Charles M. Biles

IdeaFest: Interdisciplinary Journal of Creative Works and Research from Humboldt State University

No abstract provided.


How Many Quasars Have Extremely High Velocity Outflows?, Carla P. Quintero, Sean S. Haas, Paola Rodriguez Hidalgo 2018 Humboldt State University

How Many Quasars Have Extremely High Velocity Outflows?, Carla P. Quintero, Sean S. Haas, Paola Rodriguez Hidalgo

IdeaFest: Interdisciplinary Journal of Creative Works and Research from Humboldt State University

No abstract provided.


Searching For A Connection Between Radio Emission And Uv/Optical Absorption In Quasars, Sean S. Haas, Carla P. Quintero, Paola Rodriguez Hidalgo 2018 Humboldt State University

Searching For A Connection Between Radio Emission And Uv/Optical Absorption In Quasars, Sean S. Haas, Carla P. Quintero, Paola Rodriguez Hidalgo

IdeaFest: Interdisciplinary Journal of Creative Works and Research from Humboldt State University

No abstract provided.


Rearrangements Of Fluorinated Cyclopropylamines As A Novel Approach Toward Fluoroalkene-Based Peptidomimetics, Igor Mezentsev, Vera Zaborova 2018 Moscow South-Eastern School named after V.I.Chiukov (former Moscow Chemical Lyceum)

Rearrangements Of Fluorinated Cyclopropylamines As A Novel Approach Toward Fluoroalkene-Based Peptidomimetics, Igor Mezentsev, Vera Zaborova

The International Student Science Fair 2018

Organofluorine molecules have been widely applied in various research fields because of the unique properties of fluorine atoms. One type of fluorinated compounds is fluoroalkene-based peptidomimetics which are structurally similar to amide-containing compounds. They have been prepared to improve the pharmaceutical properties such as bioactivity, target specificity, and metabolic stability of the bioactive amides.

We suggested a new way of synthesizing fluoroalkene-based peptidomimetics through 2-fluoro-2-halocyclopropylamines, which provides an effective way toward fluoroalkene-based peptidomimetics with increased functional group tolerance and possibility of convergent synthesis.


Ongoing Transposon-Mediated Genome Reduction In The Luminous Bacterial Symbionts Of Deep-Sea Ceratioid Anglerfishes, Tory Hendry, Lindsay L. Freed, Dana Fadera, Dante Fenolio, Tracey Sutton, Jose Lopez 2018 Cornell University

Ongoing Transposon-Mediated Genome Reduction In The Luminous Bacterial Symbionts Of Deep-Sea Ceratioid Anglerfishes, Tory Hendry, Lindsay L. Freed, Dana Fadera, Dante Fenolio, Tracey Sutton, Jose Lopez

Oceanography Faculty Articles

Diverse marine fish and squid form symbiotic associations with extracellular bioluminescent bacteria. These symbionts are typically free-living bacteria with large genomes, but one known lineage of symbionts has undergone genomic reduction and evolution of host dependence. It is not known why distinct evolutionary trajectories have occurred among different luminous symbionts, and not all known lineages previously had genome sequences available. In order to better understand patterns of evolution across diverse bioluminescent symbionts, we de novo sequenced the genomes of bacteria from a poorly studied interaction, the extracellular symbionts from the “lures” of deep-sea ceratioid anglerfishes. Deep-sea anglerfish symbiont genomes are ...


Internal Consistency Reliability In Measurement: Aggregate And Multilevel Approaches, Georgios Sideridis, Abdullah Saddaawi, Khaleel Al-Harbi 2018 Harvard Medical School

Internal Consistency Reliability In Measurement: Aggregate And Multilevel Approaches, Georgios Sideridis, Abdullah Saddaawi, Khaleel Al-Harbi

Journal of Modern Applied Statistical Methods

The purpose of the present paper was to evaluate the internal consistency reliability of the General Teacher Test assuming clustered and non-clustered data using commercial software (Mplus). Participants were 2,000 testees who were selected using random sampling from a larger pool of examinees (more than 65k). The measure involved four factors, namely: (a) planning for learning, (b) promoting learning, (c) supporting learning, and (d) professional responsibilities and was hypothesized to comprise a unidimensional instrument assessing generalized skills and competencies. Intra-class correlation coefficients and variance ratio statistics suggested the need to incorporate a clustering variable (i.e., university) when evaluating ...


Fitting The Rasch Model Under The Logistic Regression Framework To Reduce Estimation Bias, Tianshu Pan 2018 Pearson

Fitting The Rasch Model Under The Logistic Regression Framework To Reduce Estimation Bias, Tianshu Pan

Journal of Modern Applied Statistical Methods

This article showed how and why the Rasch model can be fitted under the logistic regression framework. Then a penalized maximum likelihood (Firth 1993) for logistic regression models can also be used to reduce ML biases when fitting the Rasch model. These conclusions are supported by a simulation study.


An Investigation Of The Tissue Distribution Of Lead In Steelhead Trout, Ciaran Edwards, Bailey Hoplight, Justin Pavan 2018 Lewiston-Porter High School

An Investigation Of The Tissue Distribution Of Lead In Steelhead Trout, Ciaran Edwards, Bailey Hoplight, Justin Pavan

The International Student Science Fair 2018

Lead is a metal that interferes with a variety of body processes and is toxic to many organs in humans and other animals. There is a legacy of lead pollution in the waterways of Western New York (WNY). Fish consumption advisories in WNY are partially based on the danger of lead contamination. However, it is not always clear if tissues of the fish that are commonly consumed are as highly contaminated as less commonly consumed tissues. In collaboration with a research team from D’Youville College, we investigated the lead concentration in different tissues of nine steelhead trout caught in ...


Greening Ut Through Service Learning, Jeanna Meisner, Linnea Vicari, Jonathan Bossenbroek Ph. D., Todd Crail Ph. D. 2018 The University of Toledo

Greening Ut Through Service Learning, Jeanna Meisner, Linnea Vicari, Jonathan Bossenbroek Ph. D., Todd Crail Ph. D.

Scholars' Celebration: Undergraduate Research Showcase

[abstract not included with submission]


Dimers On Cylinders Over Dynkin Diagrams And Cluster Algebras, Maitreyee Chandramohan Kulkarni 2018 Louisiana State University and Agricultural and Mechanical College

Dimers On Cylinders Over Dynkin Diagrams And Cluster Algebras, Maitreyee Chandramohan Kulkarni

LSU Doctoral Dissertations

This dissertation describes a general setting for dimer models on cylinders over Dynkin diagrams which in type A reduces to the well-studied case of dimer models on a disc. We prove that all Berenstein--Fomin--Zelevinsky quivers for Schubert cells in a symmetric Kac--Moody algebra give rise to dimer models on the cylinder over the corresponding Dynkin diagram. We also give an independent proof of a result of Buan, Iyama, Reiten and Smith that the corresponding superpotentials are rigid using the dimer model structure of the quivers.


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