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Full-Text Articles in Physics
Toward The Crystallization Of An Archaeal Dihydrorotase, Haley Newman, Ryan Godin
Toward The Crystallization Of An Archaeal Dihydrorotase, Haley Newman, Ryan Godin
Undergraduate Research Posters 2018
Dihydroorotase catalyzes the conversion of N-carbamoyl-L-aspartate to Ldihydroorotate in the de novo biosynthesis of pyrimidines. M. jannaschii is an archaeon that thrives in extreme environments such as the hypothermal vents at the bottom of the oceans in which both temperature and pressure are extremely high. It can serve as a model organism for research purposes. This experiment is a first step toward elucidating the structure of this enzyme in M. jannaschii. Our summer research started using a partially purified enzyme preparation from previous experiments. We further purified the enzyme primarily using hydrophobic interaction and hydroxyapatite chromatographies. Twenty-four closely related conditions …
Peer Quizzing: Are Two Heads Really Better Than One?, Leah Bunnell
Peer Quizzing: Are Two Heads Really Better Than One?, Leah Bunnell
Undergraduate Research Posters 2018
Instructors are often plagued with a difficult opened ended question; what measures can be implemented during class that will maximize students’ academic benefit? During this research project, the impact of frequent peer quizzing in introductory college level physics courses on subsequent learning assessments, such as midterms and percent gain, are examined. A peer quiz is initially administered to a student individually and graded but not returned to the students until they are given the opportunity to revisit the same quiz question with a partner. Two physics instructors’ student data is included in the data set, which is comprised of Introductory …
Characterization Of Microgels In Ionic Liquid, Dan Terrano
Characterization Of Microgels In Ionic Liquid, Dan Terrano
Undergraduate Research Posters 2018
Microgels are thermoresponsive polymeric nanoparticles whose size in aqueous solution is dependent on temperature. The microgels were studied using both dynamic light scattering (DLS) and scanning electron microscopy (SEM) to better understand the nanoparticles dynamics. The first part of the study focused on developing a controlled preparation procedure which would generate reproducible SEM images on a wet sample. The ionic liquid was mixed with a dilute solution of microgels and water was dried using nitrogen gas. This technique allowed a large volume of microgels to easily transition from their natural water solvent to a low vapor pressure ionic solvent. The …
Towards Understanding Microgel Volume Phase Transitions, Jacob Adamczyk, Samantha Tietjen
Towards Understanding Microgel Volume Phase Transitions, Jacob Adamczyk, Samantha Tietjen
Undergraduate Research Posters 2018
Microgels are polymer-based particles which are able to change size and shape during volume phase transition in response to external stimuli. We have investigated microgels which respond to changes in temperature for eventual use in drug-delivery systems on the nano to micro scale. Light scattering data on Hydroxypropylcellulose (HPC) microgels has been analyzed to determine microgel parameters such as radii, molecular weight, and polydispersity at various temperatures. The classic Flory- Huggins (FH) approach to mixing polymer-solvent solution is used to model a temperature-size dependence for the microgels. Existing theory on the microgel size dependence on the amount of crosslinker is …
The Effects Of Chemical Crosslinker On Polymeric Microgels, Samantha Tietjen, Jacob Adamczyk
The Effects Of Chemical Crosslinker On Polymeric Microgels, Samantha Tietjen, Jacob Adamczyk
Undergraduate Research Posters 2018
Microgels are nanoparticles suspended in solution and comprised of crosslinked polymer chains. Due to the amphiphilic property of the parent polymer, microgels exhibit a reversible volume phase transition. The standard behavior of these microgels is to deswell from a large to small size with an increase in temperature. Microgels in this study were synthesized by crosslinking hydroxypropylcellulose (HPC) in a surfactant solution. The amount of crosslinker used for synthesis was varied by a factor of a hundred. Using dynamic light scattering, microgels were characterized at various temperatures and scattering angles to determine the particles’ hydrodynamic radius (Rh) and dynamics both …
Characterizing The Turbulent Structure Of The Cbl And The Entrainment, Wei Jia
Characterizing The Turbulent Structure Of The Cbl And The Entrainment, Wei Jia
Undergraduate Research Posters 2018
The convective boundary layer (CBL) is the lowest part of the atmosphere. The turbulent motions in the CBL are important for redistributing trace gases, particles, heat, and momentum between the surface and the free troposphere thus it is important that this process is properly represented in numerical models that attempts to simulate the atmosphere. This study is trying to characterize the water vapor structure in the quasi-stationary CBL, using statistical way to build the turbulent model and uses a high resolution model: Large Eddy Simulation (LES) to investigate the adequacy of the model. We found that the water vapor flux …
Construction And Applications Of An Inexpensive Muon Detector, Nicholas Knyszek
Construction And Applications Of An Inexpensive Muon Detector, Nicholas Knyszek
Undergraduate Research Posters 2018
Muons are important due to the abundance of them on earth. Muons that are on earth originate from the Sun and enter Earth’s atmosphere as decaying cosmic rays. Muons are somewhat unstable, with a lifespan of roughly 2.2 microseconds. Muons decay into electrons and two types of neutrinos. Since Muons travel near the speed of light they can still go thousands of meters into the Earth’s crust before stopping. Muons account for most of the cosmic radiation at sea level. Muons are harmless to humans. In this study, we built detectors and measured muon counts at different elevations. This research …
Determining Cloud Cover With Machine Learning, Sarah Sesek
Determining Cloud Cover With Machine Learning, Sarah Sesek
Undergraduate Research Posters 2018
The cloud cover provided by boundary layer cumulus clouds is one of the greatest uncertainties in climate and weather prediction models. It is difficult with current technology to cheaply and accurately collect cloud cover data. The TSI (Total Sky Imager) provides a hemispheric field of view in order to maximize the area it can see. The farther away from the center of the image, the more angled the view of the the cloud is. Therefore, more of the side of the cloud is captured in addition to the cloud base. Machine learning is well suited to seeing through this bias. …
Investigating The Influence Of Cloud Size On Cumulus Cloud Entrainment, Theresa Lincheck
Investigating The Influence Of Cloud Size On Cumulus Cloud Entrainment, Theresa Lincheck
Undergraduate Research Posters 2018
Clouds play a crucial role in determining the weather on local and global scales, yet their complexity accounts for some of the largest uncertainties in weather forecasts and climate models. Environmental air mixing or being drawn into a current, called entrainment, is one source to blame for this complexity. When air entrains into a cloud evaporation of in-cloud condensates increase and temperatures in the cloud drop, reducing buoyancy. The overall effect of entrainment inhibits a cloud’s development, and usually results in the dissipation of a cloud. With the use of data generated from a high-resolution computer model known as Large …
An Alternative Means For Observation-Based Cloud Size Distributions, Adam Stead
An Alternative Means For Observation-Based Cloud Size Distributions, Adam Stead
Undergraduate Research Posters 2018
Clouds are a poorly understood phenomenon that have a significant impact on climate and day-to-day weather. This research aims to measure cloud size distributions for shallow cumulus clouds from observational data. Clouds are sampled via a ceilometer, which indicates both the presence of cloudy air and the base height of the respective cloud. When combining this data with the recorded horizontal wind velocity, we can infer a cloud transect size distribution. After sufficient sampling, we can use an algorithm to deduce an approximate cloud area distribution for the specified time range and cloud field. Once the cloud size distributions are …
Methodology Development For The Implementation Ofmicrofluidic Mixers, Tahir Butt, Gautam Mahajan
Methodology Development For The Implementation Ofmicrofluidic Mixers, Tahir Butt, Gautam Mahajan
Undergraduate Research Posters 2018
Microfluidic platforms have been widely regarded as defining technologies for the development of chemical and biological synthesis and analysis systems, due to benefits associated with reduced reactant consumption, increases by orders of magnitude of the surface-to-volume ratios, and greatly enhanced control over reactions variables such as temperature and pressure. However, one of the bottlenecks for their wide application is the difficulty in achieving mixing, given the typical laminar flows in these systems. In this work we implement experimentally, various strategies using geometrical features to control the fluid motion and induce stirring flows. The mixers are fabricated using soft-lithography in PDMS …
Implementation Of A Reverse Staggered-Herringbone Microfluidic Mixer For High-Throughput Polymeric Nanoparticles Synthesis, Alexa Roberts
Implementation Of A Reverse Staggered-Herringbone Microfluidic Mixer For High-Throughput Polymeric Nanoparticles Synthesis, Alexa Roberts
Undergraduate Research Posters 2018
The goal of this research is to implement and optimize the operating conditions of a microfluidic mixer to synthesize polymeric nanoparticles (NPs) in a high-throughput fashion. Using a reverse staggered-herringbone microfluidic mixer that we recently designed, the effects of experimental conditions such as flowrate and reactant composition on NP characteristics were investigated and optimized. The device design allowed for physical contact between two streams of fluids – one containing poly(lactic-co-glycolic acid; PLGA) in acetonitrile and the other deionized water, to allow for efficient mixing and NP precipitation to occur. The resulting NPs were characterized using dynamic light scattering (DLS) and …