Bulletin of the American Physical Society
Spring 2017 Joint Meeting of the Texas Section of AAPT, Texas Section of APS, and Zone 13 of the Society of Physics Students
Volume 62, Number 3
Thursday–Saturday, March 9–11, 2017; San Antonio, Texas
Session D3: Poster Session I |
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Sponsoring Units: APS AAPT SPS Chair: Evan Richards, Lee College Room: Oppenheimer Foyer |
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D3.00001: Item Response Curves for the Science Literacy Concept Inventory Crisel Suarez, Paul Walter, Gary Morris, Ed Nuhfer As has been done for the Force Concept Inventory (FCI), we examine the data of the 25-item Science Literacy Concept Inventory (SLCI) using item response curves (IRCs). The SLCI assesses science literacy through 12 science concepts, gathers data on demographics, education and socioeconomic factors. IRCs are a form of item response theory (IRT) where we evaluate each question to determine the quality of multiple-choice questions and percentage of students at different ability levels. We present preliminary results. [Preview Abstract] |
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D3.00002: Exploring student attitudes toward reformed instruction in introductory physics Gabrielle Harmon, Elizabeth Czajka, Rebel Nicholson, Chase Gammon, Eleanor Close The physics department at TXST has implemented a Learning Assistant (LA) program with reform-based instructional changes in our calculus-based introductory sequence. Students in these courses spend a significant portion of class time in small groups, often working through materials from the research-based curricular supplement ``Tutorials in Introductory Physics.'' These instructional practices, while shown by numerous studies to dramatically improve student learning, are often in conflict with student expectations and their beliefs about how they learn best. In this study, we examine written reflections completed by students in the first course in the sequence for evidence of their attitudes and beliefs with regard to the research-based instructional methods (interactive small-group learning) and materials (e.g., Tutorials) used in the course. We explore the reasons they give for their attitudes and beliefs, whether they report that their beliefs change over time, and if so, what reasons students give for the change. Findings can inform instructors on how to effectively promote productive student engagement in research-based instructional activities. [Preview Abstract] |
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D3.00003: Study strategies employed by physics students during upper level, undergraduate physics courses - a pilot study Gary Petersen, Robert Michael The purpose was to explore predominate study strategies employed by physics students during upper level, undergraduate physics courses. A survey method was employed at one regional university in Texas. Delving into differences by grade levels, study strategies employed by “A” level students include, listening to others talk about course material as a way to learn, asking oneself “why” questions to make connections between new and old material, reading and re-reading to learn material, and providing personal explanations for problems. Study strategies employed by the most “B” level students include listening to others talk about course material as a way to learn, asking oneself “why” questions to make connections between new and old material, and using reflection such as actively writing or thinking about material to make mental connections. Study strategies employed by the most “C” level students include reading to learn material, taking notes when reading, and using concept mapping or imagery. Based on these findings faculty could encourage study strategies employed by “A” through “C” level students, but may suggest those employed by high performing students. Although differences appear to exist, higher numbers of respondents are necessary to establish significance levels. [Preview Abstract] |
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D3.00004: Trends in Houston Surface Ozone Levels Andy Barnes, Gary Morris, Paul Walter We examine how the diurnal ozone cycles of surface ozone in Houston have changed in the spring and summer seasons over a time period long enough to establish trends in the data of statistical significance. We initially consider a 4-5 year time period as a test and then will investigate the record back to 1980 at 9 separate stations in the Houston-Galveston-Brazoria area. We also report on the daily maximum and minimum averages as well as the max 8-hour average by season over that time period. [Preview Abstract] |
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D3.00005: Adding[?]-Values in Contemporary Economies through ``Danding'' Cojuanco C. Helmy Herlambang, SE, August Parengkuan, HE. Mr, H. Dedi Muhtadi, SE Instead as well as 'bamboo 0,4 mm line' {\&} `binder note high --C' to Bilan {\&} Roman: \textbf{"Interconnections between Public Indebtness {\&} Inflation in contemporary Economies", }\underline {Economics {\&} Socilogy}, hidden Years we have \textless https;//en.wikipedia.org/wiki/Cluster\textunderscore munition\textgreater also of "inflationary universe {\&} somorphicity" Andrei Linde provides cq :\textbf{"Particle Physics"}completes the \textbf{ INDUSTRIALIZATION to be Export Promoting {\&} Import Substitutions prefers. }We intends to relates "preent value"/Yukawa potential to "accumulation value" of Plack equation requires to appreciates the Georg Windsor Earl Historian to HE. Mr. Drs. P SWANTORO through "GlobalWirelessE-Voting machine" from Reddy Mahendra Reddy adding-values of HE. Mr. Prof. B.J. HABIBIE added-V to "Danding" COJUANCO fulfills. [Preview Abstract] |
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D3.00006: Quantum Physics for High School Teachers Karen Jo Matsler, Thomas O'Kuma Thanks to a grant provided by the American Institute of Physics, workshops targeting quantum concepts were offered in the summer of 2016 at Lee College, Fort Worth Museum of Science, and Austin College. The professional development format of these workshops was unique in that both high school students and teachers attended the workshop. The curriculum and resources developed by the Perimeter Institute for Theoretical Physics. In this poster, we will share the strengths and weaknesses of this model as well as the data. [Preview Abstract] |
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D3.00007: ATE Workshops for Physics Faculty Thoms O'Kuma The ATE Workshop for Physics Faculty project is finished after completing 14 3-day workshops and 10 3-day working conferences. In this poster, we will display information about what the project accomplished. [Preview Abstract] |
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D3.00008: Challenges and Rewards in Directing Undergraduate Research Projects Andra Petrean Over the last year I directed a few undergraduate projects involving depositing and characterizing films at nanoscale. Some of the research was done exclusively at Austin College, and some was in collaboration with a group within the Materials Science and Engineering Department at University of Texas at Dallas. The number of students in the teams I directed varied between one and three, and the students' prior experience with the systems under study and their physics background varied greatly. The measurements included Hall effect, electrical, and optical measurements. I will discuss both the challenges and the rewards of directing the different teams. [Preview Abstract] |
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D3.00009: Study of the Dynamics of the Nature Inspired Turbine Blade Kyeong Min Kim, Seung Ki Lee, Richard Kyung Blade is the most significant part in the wind generator. The windmill used in wind power generation is a turbine, which rotates with high angular velocity. Due to the great amount of centrifugal force applied to the blade during rapid rotation, the shape of the blade is crucial for its efficiency. In addition, accuracy of the balance between blades should be improved. The ideal shape of the wind turbine, as with maple seeds falling in spiral motion, can be found in nature. Although each maple seed embraces a unique shape, all fall with continuous spiral motion. Therefore, establishing a relationship between the shape of maple seeds leads to a universal design of wind turbines. A few of the blade shapes developed by National Advisory Committee for Aeronautics(NACA 4412-4418) were used for the simulations. There was no significant difference of coefficient of lift due to difference in thickness, but coefficient of drag was increased as the thickness was increased. Also the relations between Coefficient of drag vs. Coefficient of lift has been found for the NACA 4412-4418. This paper uses computational software to design a wind turbine considering angle of attack, speed and density of the wind, and shapes of blade. [Preview Abstract] |
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D3.00010: Study on the Mood Regulations and Antipsychotic Substances Min Kyung Seong, Richard Kyung The main causes of depression are known to be faulty mood regulation, genetic susceptibility, stressful events, and medical issues. In better understanding the diagnosis of depression, technological advancements, such as brain imaging technology, have played a significant role. With the help of technology, quantifiable measurements of neurotransmitters such as Serotonin, GABA, Acetylcholine, Dopamine, and Glutamate have become an essential site for observation of depression. Although there are no known cures of depression, computational biomedical simulation technology has been perceived as being a possible solution for depression and anxiety in recent years. In this paper, using the modern tools, antipsychotic substances such as Reserpine molecule and CRF complexes are analyzed as they are able to give the psychological problems. The use of alternative complexes might lead to a solution with less active energy and greater efficiency. Used programs are capable of building a virtual molecule with optimized geometry using GAFF (General Amber Force Field) and then UFF (Universal Force Field). The theoretical structure of each feasible compound is also studied by using the stability of each molecule to predict the efficiency of the molecule in assessing the thermodynamic stability. [Preview Abstract] |
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D3.00011: Assembling, cleaning, and testing a unique prototype open-ended cylindrical penning trap Kassie Marble, Daniel Marble, Dan Melconian, Praveen Shidling A new experimental beamline containing a prototype cylindrical penning trap has recently been constructed at the Cyclotron Laboratory at Texas A{\&}M University. The new beamline will enable precision experiments that enhance our understanding of the limits on non-SM processes in the weak interaction through the measurement of the $\beta $-$\nu $ correlation parameter for T $=$ 2, 0\textasciicircum $+\to $0\textasciicircum $+$ superallowed $\beta $-delayed proton emitters. The prototype TAMU TRAP consists of an open-ended cylindrical penning trap of diameter of 90 mm with gold-plated electrodes of oxygen free high conductivity copper to prevent oxidation. The trap's electric quadrupole field is provided by a SHIP TRAPS RF electronic circuit to the four segmented electrodes at the center of the trap while the trap's 7 Tesla magnetic field is provided by an Agilent 210 ASR magnet. A discussion of the assembly of the TAMU TRAP, the experimental setup, and alignment of the beamline will be presented. The method used to test the prototype penning trap using an ion source, Faraday cups, and micro-channel plate (MCP) detectors will also be discussed. [Preview Abstract] |
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D3.00012: Enhanced Efficiency of Solar Cells Using Reflectors and Metamaterials Yun Jin Jeong, Richard Kyung Solar power is produced by converting energy from the sunlight to electricity, thermal energy and other types of energy. To find the optimum environment for the maximum efficiency of solar energy production, this research shows various experiments to test different reflector shapes, altering the shape of the reflector on the solar panel to achieve highest efficiency. These alterations include plane reflector, spherical reflector, and parabolic reflector. By measuring the temperature change on the surface of the reflector and the amount of electricity produced by a voltmeter, the efficiency of each reflectors are compared. Light intensity and incident angle are considered since they are the most significant and influential factors of the production of electricity from photovoltaic cells. This paper also shows that how infrared or visible-frequency electromagnetic waves works with nano-scaled metamaterials, resulting in augmented payloads, longer missions and increased payloads. A novel concept in UAVs and satellite battery technology involves Surface Plasmon Polariton. The SPP uses metals and metal oxides to store solar energy, maximizing optical strength by exciting absorption layer with SPP mode through adjustments made with the incident light. [Preview Abstract] |
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D3.00013: Stem Cell Bio-Image Resolution Enhancement Using a Polynomial Transformation Yoonjeong Kwon, Richard Kyung For a certain bio images obtained from a device, the bio-image process requires more work for morphological reconstruction than mere quantitative analysis, such as measurements. To apply various enhancement methods to produce a better image of a stem cell, we gathered the raw data and images on stem cells. We are able to improve the quality of the bio-image in a pixel scale by using a computational and mathematical method employing spectrum modification. By performing linear and quadratic transformation, a strategy for enhancement of bio-imaging technique is presented in this paper. Using histogram equalization of stem cells, which provides quantitative information about the condition of the cells, the shape, size, and coloration were studied. This research, by combining the histogram analysis and the proposed transformation, is conducted to observe an improved algorithm that increases the stem cell image quality. Previous attempts of enhancing bio-images by preprocessing, watershed segmentation, and morphological image processing had no significant effect on the quality of images. This research shows more effective algorithms in resolution enhancement and better segmentation of the stem cell as well as corneal epithelial cells using spectrum modification. [Preview Abstract] |
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D3.00014: Rotation Light Curves and Taxonomy of 15$^{\mathrm{th}}$ to 19$^{\mathrm{th}}$ Magnitude Asteroids Landrie Granthum, Mike Hibbs Knowledge of the composition, shape and rotation rate of an asteroid is extremely important in; evaluation the impact damage potential; development of impact avoidance strategies; and evaluating the feasibility and economic potential of mining. However, little data exists for the vast majority of known asteroids other than their orbital parameters. Observations made by Tarleton's 0.81-meter telescope has produced several light curves and color indices of asteroids from 15$^{\mathrm{th}}$ to 19$^{\mathrm{th}}$ magnitude. This work represents the unique niche of Tarleton's 0.8m telescope to collect statistically meaningful data as faint as 19$^{\mathrm{th}}$ magnitude. Large professional survey telescopes do not have the time to do follow-up observations while smaller professional/amateur telescopes are too small to achieve a high enough signal to noise ratio to determine rotation periods and composition of the fainter and smaller asteroids. This poster, summarizes and presents some of Tarleton's observations and data analysis. [Preview Abstract] |
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D3.00015: Probing Ion Behavior in Porous Carbon Membranes Under Applied Electric Potential Through\textit{ In Situ }SAXS Experiments. Francisco Ayala Rodriguez, Pasquale F. Fulvio, Lawrence M. Anovitz, Jose L. Bañuelos Ion transport and sorption kinetics in soft-templated mesoporous carbon is being studied using small-angle x-ray scattering technique (SAXS). Previous voltage-dependent small-angle neutron scattering (SANS) experiments have shown that this technique can be used to detect structural changes due to ion adsorption at the solid-liquid interface and in the structure of the carbon membranes as the voltage is varied. The average structure of the MC-127 membrane is being determined through the use of SAXS and SASview analysis software. MC-127 has a cylindrical morphology with an average pore-pore distance of 9.4nm. Other properties contribute to its SAXS signal: these include a small spherical shape due to micropores as well as the presence of a second structural correlation at distances larger than the pore-pore distance. To probe ion behavior, a prototype electrochemical cell previously used for SANS is being modified. Efforts are underway to test the cell's performance in a vacuum environment, and the overall electrochemical performance for a given electrode/electrolyte assembly. The current effort will aid the development of better supercapacitors with an optimized electrolyte and electrode geometry combination. [Preview Abstract] |
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D3.00016: Study on Aquatic and Terrestrial Life in Well Preserved Area Using Computational and Physical Modeling Min Jae Kim, Seoyoung Kyung For most natural life in well-preserved aquatic and terrestrial environments to continue their existence, local administrations, policy-makers, careful visitors, and scientific concerns must devise good strategies to build a safe boundary for proliferation and preservation of endangered wild life. These strategies include, but are not limited to, controlling temperatures and minimum concentration of dissolved oxygen of the aquatic life. Therefore, in order to protect aquatic and terrestrial life in a given area, a study on the social customs of the local people and prediction of the critical saturation deficit of environmental factors is crucial in preventing extinction of well preserved life. In performing this study, this research uses computational simulations and mathematical modeling taking account of many factors. [Preview Abstract] |
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D3.00017: Study on the Mechanics of a Wind Turbine to Produce Efficient Wind Energy Jaihong Oh, Richard Kyung Blades and turbines, rotating with high angular velocity to create centrifugal force, are the sources of a windmill's power generating force. The shape of blades influences the amount of generated centrifugal force. Therefore, in considering wind power generation, this research studies physics and fluid mechanics of blade to enhance the windmill's efficiency and accuracy. In studying the ideal flow through an actuator disc, momentum theory, tangential velocity, and accelerations are considered. In the simulations for the several NACA types of blades, comparisons of the ratio of lift coefficient to drag coefficient were found. Reynolds numbers, densities, and Mach numbers of the air were considered finding relationship between drag coefficient and lift coefficient. Incorporating these records, this research proposes ideal wind blades using computational software to simulate the angle of attack and other variables of the wind. [Preview Abstract] |
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D3.00018: Stability and Thermodynamic Analysis of the Luminol Molecule and its Derivatives Using Computational Simulations Inyoung Choi, Sieun Lee, YongWoo Lim, Chai Rin Kim Application of luminol that helps analyze blood evidence at crime scenes and develop biosensors is important in Forensic, medicine, and plant sciences research. The theoretical and computational analysis of the luminol molecule and its derivatives were presented in this research to identify the electronic density as functional. Optimized energies(kcal/mol) of luminol’s derivatives, analyzed through computational calculations, revealed molecule's stability based on the electronic density functional analysis. Each of the molecule's stability of different derivatives of luminal tautomers, compared with the original luminol has been recorded as numerical data. This numerical data translated to stability order, and an analysis on the stability order confirmed the use of electronic density analysis as functional. The study further presented a few influential factors of luminol’s tautomers' relative stability. Also light reaction times were checked when luminescing solution reacts with other solutions. The main factors were found to be the aromaticity and electronic delocalization. Such factor is determined by the quantity of molecular orbitals of p character. Another factor consists of the molecule’s hydrogen bonding. The final, most important, factor was the charge distribution. [Preview Abstract] |
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D3.00019: The effect of time on the dehydration of CsH$_{\mathrm{2}}$PO$_{\mathrm{4\thinspace }}$at 260 C using XRD Andrea Montgomery, Israel Martinez, Juan Leal, Alan Goos, Alex Price, Heber Martinez, Cristian Botez Solid Acids such as Cesium Dihydrogen Phosphate, CsH$_{\mathrm{2}}$PO$_{\mathrm{4}}$ (CDP), are excellent electrolytic material for the construction of intermediate temperature range hydrogen fuel cells. CDP exhibits a high protonic conductivity at temperatures ca. 235 C. Associated with the increase in conductivity, there is a polymorphic transformation from a monoclinic crystalline structure to a cubic structure. However, at the temperature that high conductivity is achieved there is a competing chemical dehydration process, which causes a phase transition from the cubic phase (CDP) to a pyrophosphate monoclinic phase. This appears to be the onset of the decline in conductivity of the material. Chemical decomposition (dehydration) of the material has been reported to be delayed heavily with the introduction of water vapor. In order to prevent the decomposition, it is imperative that data is gathered about the dehydration process. [Preview Abstract] |
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D3.00020: Structural modifications in the RbxCs1-xH2PO4 (0$\le $x$\le $1) superprotonic conductor series: a single-crystal x-ray diffraction and impedance spectroscopy study. Alan Goos, Andres Jose Encerrado Manriquez, Heber Martinez, Alex Price, Cristian Botez We have used single-crystal x-ray diffraction to investigate the structural modifications induced by Rb-doping of the superprotonic conductor CsH2PO4. Our data collected on the RbxCs1-xH2PO4 (0 $\le $ x $\le $ 1) series shows that the monoclinic P21/m CsH2PO4 modification persists upon Rb-doping up to x $=$ 0.8. We found that Rb0.8Cs0.2H2PO4 exhibits a previously unreported P21/c monoclinic structure, where the mirror plane is lost and disorder is present in the PO4 tetrahedra even at room temperature. Higher levels of x display a tetragonal I-42d unit cell isomorphic with the known structure of RbH2PO4. The temperature dependence of the proton conductivity determined from impedance spectroscopy data collected within the 160\textdegree C-250\textdegree C range is also markedly different at high Rb-doping levels, x $\ge $ 0.8. Finally, we found that Rb0.9Cs0.1H2PO4 undergoes a transition from its room-temperature tetragonal I-42d phase to an intermediate-temperature monoclinic P21/m modification at a significantly lower temperature (\textasciitilde 80 \textdegree C) than its RbH2PO4 counterpart (\textasciitilde 120 \textdegree C). [Preview Abstract] |
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D3.00021: Stability enhancement of solar absorber material Cu$_{\mathrm{2}}$S by Ag alloying. Sajib Barman, Muhammad Huda Cu$_{\mathrm{2}}$S is an important solar absorber material and has great prospect in the field of renewable energy. However, this material suffers from instability due to spontaneous Cu vacancy formation and Cu diffusion in the structure. The spontaneous Cu vacancy causes the material to possess high p-type doping, which leads the material to behave as a degenerate semiconductor. This is a vital obstacle for this material to be used as an effective solar absorber material. A relatively new predicted phase of Cu$_{\mathrm{2}}$S which has an acanthite-like structure was found to be more preferable than the well-known low chalcocite Cu$_{\mathrm{2}}$S. However the Cu-vacancy formation tendency in this phase remained similar. We have found that alloying silver with this structure can help to reduce Cu vacancy formation tendency without altering its electronic property. The band gap of silver alloyed structure is higher than pristine acanthite Cu$_{\mathrm{2}}$S. In addition, Cu diffusion in the structure can be reduced with Ag doped in interstitial sites. Here, we present a systematic approach within the density functional theory framework to study Cu vacancy formation tendency and diffusion in silver alloyed acanthite Cu$_{\mathrm{2}}$S, and proposed a possible route to stabilize Cu$_{\mathrm{2}}$S against Cu vacancy formations by alloying it with Ag. [Preview Abstract] |
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D3.00022: Determining the density if the ionic liquid [C10MPy][Tf2N] confined in silica nano pores using small-and wide-angle x-ray scattering Melissa Cano, Pasquale Fulvio, Gernot Rother, Jose Leobardo Banuelos The structure of the ionic liquid (RTIL), [C10MPy] [Tf2N], confined in silicas with 8 nm and 2.8 nm pores was investigated. RTILs have negligible volatility, excellent thermal and electrochemical stability, and are of interest in areas such as nano-lubrication, energy storage, and environmental and materials synthesis. The dynamics, structure, and thermodynamics of RTILs under confinement are not completely understood, yet elucidating these properties is key to new advancements. Previously, confined RTIL dynamics were probed with neutron spin echo spectroscopy (NSE), and structural properties were probed with small-angle neutron scattering. In this work, small- and wide-angle x-ray scattering (SWAXS) results (Q-range:0.01-3{\AA}$^{\mathrm{-1}})$ of the confined RTIL are presented. The higher Q-range in these new measurements gives access to inter-ion distances, and allows us to correlate them to the RTIL density inside pores and the NSE dynamics. The confined RTIL density was obtained by calculating the scattering invariant and applying a model to the empty and RTIL-filled silicas. The relation between RTIL structural peak parameters and measured density and dynamics will be discussed. [Preview Abstract] |
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D3.00023: Spectroscopic investigation of antimicrobial nanoparticles jingyao dou, Dmitri Voronine E. coli is a common bacteria for spectroscopic analysis of antimicrobial agents. We use plasmonic metal nanoparticles for inactivation of bacteria and nanoscale spectroscopic analysis of the effect of the nanoparticles. Scanning probe microscopy such as SEM and AFM can be used for nanoscale imaging of the bacteria-nanoparticle interactions. We investigate the effects of the laser wavelength and temperature on the bacteria. [Preview Abstract] |
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D3.00024: Elongation affinity of A$\beta$-42 via molecular dynamics simulations Roberto Rodriguez, Liao Chen, George Perry A number of diseases including Alzheimer's, Parkinson's, and Huntington's are characterized by the presence of fibrillar aggregations of amyloid-$\beta$ (A$\beta$) peptides. The 42-residue variant A$\beta$-42 has emerged as a key factor in the pathology of Alzheimer's disease. Very recently, the functional structure of A$\beta$-42 fibrils has been elucidated via high-quality NMR studies. We conducted molecular dynamics simulations on this recently published structure and calculated the free energy needed to elongate an A$\beta$-42 fibril, finding excellent agreement with experimental measurements. We also studied the effect of the mature amyloid fibrils on the conformational stability of free peptides attached to their surface, and find that at least a dimer is needed for the free peptides to retain their fibrillar conformation, in support of the well-known second-order secondary nucleation mechanism. [Preview Abstract] |
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D3.00025: Study of the Neurochemicals Creating Happiness and Positive Psychology Hee Soo Kim, Richard Kyung The feeling of happiness is not merely the result of a single neurochemical in the brain. Rather, happiness is dependent on seven different neurochemicals that are affected by one's lifestyle. Knowing which daily activities release certain neurochemicals related to happiness and partaking in such activities will increase one's likelihood of achieving happiness. Electrical brain waves, brain structure, and neurochemicals are important in emotional processes. This paper specifically examines neurochemicals in relation to happiness. Happiness is dependent on four neurochemicals known as Dopamine, Oxytocin, Serotonin, and Endorpins (DOSE). Each neurochemical has an independent function in creating one's happiness. Discovering which day-to-day activities trigger the release of such neurochemicals will result in higher daily happiness levels. Higher happiness levels, in turn, increase productivity. In this research, Chemcraft and Avogadro were used, as they are capable of determining the theoretical and chemical properties of the “happiness molecules”. The theoretical structure of each feasible neurochemicals has been studied by using the stability of each molecule to predict the efficiency of the molecule in assessing the physical stability and measure of the happiness itself. [Preview Abstract] |
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