Session D1: Poster Session (16:00-17:00)

Spatiotemporal Analysis of Respiratory Tract Infection Dynamics

Respiratory tract infections are easily among the most diagnosed illnesses in modern medicine, especially involving infants and the elderly. Lower respiratory tract infections (LRTIs) are especially dangerous, often capable of producing lasting respiratory problems, increased hospitalization, and life-threatening illness. Our research is targeted towards uncovering a possible mechanism behind the spreading of LRTIs, in hopes of illuminating the connection between the diffusion of a given virus and the speed, or advection, of mucous transfer within the respiratory tract. This project more specifically focuses on a system of nonlinear ordinary and partial differential equations which simulate the diffusion and advection driven dynamics of an infected respiratory system. With a more realistic spatiotemporal approach, we have been able to gather possible relationships between given rates of advection and diffusion, and the depth and duration of infection; a potential framework for understanding and preventing an otherwise refractory human affliction.   

Heated Cell to Study Sarin Surrogates Using Laser Absorption Spectroscopy in the 3.39 $\mu $m Infrared Region.

A heated cell with optical access has been constructed to characterize spectroscopic parameters for various low-vapor-pressure constituents of interest in the aerospace, power generation, and defense industries. Sarin gas (C4H10FO2P) is a dangerous nerve agent used in chemical weapons of mass destruction. Due to the toxicity of Sarin gas, it is difficult for the experimenter wanting to develop reagents that help eliminate or mitigate its effects. Surrogates for Sarin, which have similar organophosphorus bonds but are much less toxic, are being studied at elevated temperatures and pressures to develop better chemical kinetics mechanisms to predict the behavior of Sarin destruction. Resolution of low-vapor-pressure species concentrations for sample surrogates is not trivial as gas dynamic effects during the experiment can lead to condensation of the species. Laser absorption spectroscopy offers a non-invasive diagnostic that is highly sensitive and allows for in-situ measurements of species concentrations. Measurements were made with a 2 mW 3.39 $\mu $m helium-neon gas laser in the infrared region that is sensitive to the C-H bond in hydrocarbons. The laser passes through a gas chamber with sapphire windows, heated to constant temperatures of up to 473 K, and is focused into an infrared-sensitive PbSe photodiode. Transmission was measured by the fractional attenuation of light through the cell at known conditions to record absorption coefficients and will be used to develop spectroscopic data for other species of interest.   

Continuous {\&} Discrete Dichotomy of Space-Time

In lectures from HE. Mr. Prof. SriJatnoWirjosudirdjo those were Sintesa I/II -1984 in Prodi of Physics ITB through i.e \textit{``sinyal waktu kontinyu'' }n coincidences to Fractal Signal from Wornell and devoe t HerMajesties Mvr Hj Dr-HC DYAH MEGAWATI SOEKARNOPUTRI depict in \underline {https://www.youtube.com/watch?v}$=$\underline {q4SSe6TMeKo} reminds by \textbf{. }Dichotomy arises from ``discrete-time scattering process'' describe by Borgonovi {\&} Guarneri, \underline {PhysRev B,}, v 52 n 5, Aug 1, 1995 as well as ``nondifferentiable continuous space-time sought in Nottale: \textbf{Scale Relativity {\&} Fractal Space-Time: Theory {\&} Applications'' }2009.. Overwhelms ``Astranomics'' 2015/17 proposed herewith ``\textit{superuniversality'' }from Newhouse {\&} Kopelman inspired setbacks to May 11, 1976 Cornell University announced to/from Stephen Hawking's \textbf{``A Brief History of Time''A.B.H.T/}\underline {\textbf{bathysphere}} and forgotten Writer of \textbf{``What is Time?''/}ITB 1980 \textit{``Segala yang kupunya}\textellipsis '' as fractal-space time denotes discrete properties.   

Density Functional Theory study of first order phase transition in 2D lattice fluid

The Density Function Theory is used to calculate phase diagrams and interfacial properties in two-dimensional lattice fluid. In order to accomplish this, simplifications had to be made to the lattice fluid model. First, only the nearest neighbor and next-nearest neighbor interactions were accounted for. Second, the fluid was taken into consideration without any external field present. With these simplifications, thermodynamic potentials could be found as functions of density. The density profiles for one and two dimensional liquid-vapor interfaces were studied at different temperatures and different supersaturations. The behavior of the surface tensions for a planar and curved liquid-vapor interface was studied as well.   

Stratospheric Organism and Radiation Analyzer (SORA)

The SORA payload sampled for the existence of microorganisms and bacterial spores in the upper atmosphere. The payload analyzed different aspects of the surrounding environment such as radiation exposure, temperature, pressure and humidity. The payload had three main scientific objectives. First, design and build a novel system that will isolate surrounding air and sample for cells. Second, on--board sensors analyze exposure to solar and cosmic radiation that microorganisms may encounter. Finally, monitor the environmental conditions such as temperature, pressure, and humidity. Furthermore, the design employed additive manufacturing and hobby electronics in its construction to provide an accessible basis for future missions and explore the bounds of the technology available. SORA established a proof of concept for collecting air samples using a low pressure vacuum pump. Onboard sensors gathered a wealth of information regarding surrounding radiation, with a peak dosage rate of about 0.07 $\mu$Gy/min at ascent and about 0.05 $\mu$Gy/min during float. Finally, SORA monitored the environment for the duration of the flight, successfully testing the prototype flight computer, while keeping the power consumption below 1.5 A at 30 V.   

Investigating the Nature of Dwarf Spiral Galaxies

Dwarf galaxies are the most numerous galaxies in the universe, yet little is understood about their evolution. Several studies have proposed that dwarf elliptical / spheroidal galaxies form through the transformation of dwarf irregular galaxies. Early and late type dwarfs resemble each other in terms of their observed colors and light distributions (each can often be represented by exponential disks), providing reason to propose an evolutionary link between the two types. The existence of dwarf spirals has been largely debated. However, more and more recent studies are using the designation of dwarf spiral to describe their targets of interest. This project seeks to explore where dwarf spirals fit into the above mentioned evolutionary sequence, if at all. Optical colors and spectra will be compared amongst a sample of dwarf spiral galaxies in an attempt to confirm their status as dwarf galaxies. Additionally, the dwarf irregular and dwarf elliptical samples have previously been found to overlap in both color and surface brightness profiles shape when limiting the samples to their fainter members. A preliminary comparison including the dwarf spiral sample will be presented here. Initial results indicate a potential evolutionary link that merits further investigation.   

Identifying Milky Way Stellar Populations Through Kinematics Derived from Catalog Data

The GAIA mission, launched in 2013, will provide the precise position, distance, and motion on the sky for an unprecedented number of stars in the Milky Way (MW). ~The first set of data from the mission was released in 2016 and astronomers are already updating measurements and making discoveries with the new information. We have cross-matched this photometric catalog with the spectroscopic surveys of RAVE, SDSS, and LAMOST to provide stellar parameters and radial velocities. ~With this combined dataset we are able to compute orbits for the stars and can isolate various stellar populations to study properties of our Galaxy. We will present our catalog and method, as well as show orbital properties of different MW populations.   

Observation of interlayer phonon modes in few-layer CrI3

Chromium triiodide (CrI3) is an Ising ferromagnet with van der Waals interlayer coupling. Atomic layers of CrI3 have been demonstrated to display 2D ferromagnetism which makes them potential candidates for data storage applications. We used ultralow frequency Raman spectroscopy to probe the interlayer coupling in CrI3 atomic layers produced by mechanical exfoliation. We observed the lowest-frequency branch of layer breathing mode (LBM) vibration in the atomic layers. The LBM redshifts dramatically with increasing number of layers, similar to that seen in few-layer graphene. The shear modes are not observed in CrI3 atomic layers. The LBM frequency does not show a strong temperature dependence. Our studies offer the first direction observation of interlayer phonons in CrI3.   

VSM measurements on NiFe-oxide samples

Radio Frequency (RF) sputtered NiO thin films find application in various novel devices, including solar cells, batteries, computer memory, sensors, catalyzers, and gas sensors. The electric properties of NiO can be modified by changing the ratio of oxygen to metal atoms. In addition, it is possible to modify the materials crystallinity by doping it with other transition metals modifying grain size and defect density. Here, we discuss the magnetic properties of reactive RF sputtered NiO and Fe-doped NiO thin films sputtered at different O$_{\mathrm{2}}$ flow rates ranging from 0.8 to 10 sccm. NiO films sputtered with high O$_{\mathrm{2\thinspace }}$flows are highly conductive and transparent suggesting the presence of metal vacancies. Films deposited with an oxygen flow less than 1.25 sccm are not completely oxidized and have a large non-zero magnetization. The incomplete oxidation is confirmed by X-ray measurements which show the appearance of a metallic peak in the XRD data for lower O$_{\mathrm{2}}$ flow samples. XPS measurements performed to verify the metal to oxidation ratio of the samples will be discussed as well. We acknowledge financial support from DOD (HBCU/MI grant W911NF-15-1-0394).   

Study of p-type behavior in NiO doped Cu and Ag using ab initio calculations

NiO has become an active area of research due to it's potential to be used in the next generation of Resistive RAM (RRAM) devices. Thus it is of interest to study how this material behaves in response to introduced impurities in order to ascertain if the doped system improves desired properties. To that end, we have used Density Functional Theory (DFT) together with the VASP-PAW method based ab initio calculations to study the effects of introducing Cu and Ag atoms via replacing Ni into pristine NiO. Exchange-correlation effects were included in the calculations within the generalized gradient approximation (GGA). To better describe the d-orbitals of Ni, Cu, and Ag, a Hubbard potential U contribution was added (GGA+U), in all systems studied. Preliminary results also considering a hybrid functional (HSE06) to treat the exchange correlation are shown. The pristine and doped NiO systems were studied using supercells grown along the [111] direction of 4 and 32 atoms in order to simulate antiferromagnetic configurations for the pure NiO and doped systems respectively. Concentrations of Cu and Ag of 6.25% and 12.5% were investigated. Our results are analyzed in relation to p-type character for Cu- and Ag-doped NiO.   

Measuring the Effects of Sensitivity to Initial Rotational Conditions on Rigid Body Dynamics

Our experiment concerns the mathematical and experimental observation of a sensor-enabled parallelepipedal object in free-fall to test its sensitivity to initial rotation conditions. The independent variable manipulated in our process of experimentation was the axis along which the parallelepipedal object rotates, with the expectation that the intermediate or $z$ axis (where the lengths of the object are: $x > z >y$) would produce greater sensitivity to initial conditions in accordance with the interpretation of the mathematics driving the expected motion of the object. To test the predictions of theory, an experiment was devised wherein we went to the top of our university science building and did controlled drops of a Pasco Smart Cart off of a sharp ledge along all three axes. This allowed the cart to experience free fall, drag force, and rotation along all three axes. The data were then parsed and modeled using code written in Mathematica allowing for quantitative analysis of the experimental results.   

On the Formulation of Homotopical Mechanics

Let M$_{\mathrm{G}}$ be a path-connected and simply connected space over a gravitational field G. Let $\alpha_{\mathrm{i}}$ be a free-fall path on M$_{\mathrm{G}}$ for $i\in Z$(set of integers). The Hamiltonian ${\rm H}$ for $\alpha_{\mathrm{i}}$ obeys the homotopy theory. We showed that the Euler-Lagrange's equations for $\alpha_{\mathrm{i}}$ can be expressed in terms of a homotopy map between the kinetic energy u(t) and potential energy v(t) for $\alpha_{\mathrm{i}}$, here t$\in $ [0,1].   

Animated Soft Particles as the Receiver and Analyzer of the Information.

Fundamental Particles (FP) need to know their next quantum state. Therefore, they should have ability of getting packages of information (super soft (i. e. zero energy) particles) and analyze it for understanding their next quantum state. Receiving super soft particles can be done by soft particles (sub-particles). Particles which have different soft particles but are otherwise identical. For example, soft quarks involving quark, get the super soft quarks (information for quarks), for analyzing and understanding quark's next quantum state. The soft gluon gets super soft gluon (information for gluons) for finding its pathway for interaction with quarks. Also, this story occurs for soft photons and gravitons. In this way, it seems there are four soft particles of mater, plant, animal and human in substructure of each FP (string) as the origins of the life and cause of spins and orbital angular momentum of those FP. Material's soft particle always is on and active. When the environmental conditions became ready for creation of each field of the plant, animal and human, soft particles of their FP became on and active and then, those FP participated in processes of creation in their own field [Gholibeigian Hassan {\&} Zeinab, AGU. 2015. adsabs.harvard.edu/abs/2015APS..APR.L1027G].   

Search for stop and gluino production with improved top quark identification using machine learning

Some well motivated models of Supersymmetry(SUSY) propose that the superpartners of the heavy 3rd generation quarks (top and bottom), called the stop and sbottom squarks, will have their masses at the TeV-scale, within the reach of experiments at the LHC. We expect that their decay would result in an excess of events with top and bottom quarks. Identifying top quarks is an ongoing topic of research. We present a method of identifying top quarks using machine learning, and present the results of a search for gluino and stop production decaying into all hadronic final states using data collected by the CMS detector at the LHC of proton-proton collisions at a center of mass energy of 13 TeV and integrated luminosity of 35.9 fb^{-1}.   

Characterization of ParTI Phoswiches Using Charged Pion Beams

The Partial Truncated Icosahedron (ParTI) detector array consists of 15 phoswiches. Each phoswich is made of two scintillating components -- a thallium-doped cesium iodide (CsI(Tl)) crystal and an EJ-212 scintillating plastic -- coupled to a photomultiplier tube. Both materials have different scintillation times and are sensitive to both charged and neutral particles. The type of particle and amount of energy deposited determine the shape of the scintillation pulse as a function of time. By integrating the fast and slow signals of the scintillation pulses, a ``Fast vs. Slow Integration'' plot can be created that produces particle identification lines based on the energy deposited in the scintillating materials. Four of these phoswiches were taken to the Paul Scherrer Institute (PSI) in Switzerland where $\pi +$, $\pi $-, and proton beams were scattered onto the phoswiches to demonstrate their particle identification (PID) capabilities. Using digitizers to record the detector response waveforms, pions can also be identified by the characteristic decay pulse of the muon daughters.   

First-Principles Study of Phase Stability of \textit{bcc} XZn (X $=$ Cu, Ag, and Au) Alloys

First-principles density functional theory is used here to study phase stability/instability and anomalies in formation of the \textit{bcc} phases of the aforementioned XZn (X $=$ Cu, Ag, and Au) alloys. The CuZn and AgZn alloys have a disordered \textit{bcc} structure at high temperature; however, this is not the case for the AuZn alloy. The AgZn alloy also has a lower \textit{bcc} order-disorder (critical) temperature compared to CuZn and AuZn alloys. It is shown that these anomalies in \textit{bcc} structure of XZn systems can be explained in terms of the bond strength between the X and Zn atoms. Charge density studies and pair potential modeling of XZn alloys show that the Ag-Zn bond is significantly weaker than the Cu-Zn and Au-Zn bonds. The lattice parameters, bulk modules, elastic constants, Debye temperatures, and heats of formation for the \textit{bcc} phases of the three XZn alloys are calculated and compared with available experimental values.   

Raman Spectroscopy Analysis of a New Copper-Cysteamine Complex.

A recently synthesized copper-cysteamine complex with strong luminescence, Cu$_{\mathrm{3}}$Cl(SR)$_{\mathrm{2}}$, where R $=$ CH$_{\mathrm{2}}$CH2NH$_{\mathrm{2}}$, has been identified with potential applications in radiation detection and cancer treatment.$^{\mathrm{1}}$ In order to better understand the microstructure of this material, we have utilized Raman spectroscopy and several other characterization techniques to look into possible correlations between the microstructure and average crystal size in this material. The Raman spectroscopy and FTIR data identify numerous bonds having wavenumbers from 200 to 3500 cm$^{\mathrm{-1}}$, SEM and EDS measurements reveal average crystal size $\left( {\le 4\mu m} \right)$ and relative elemental composition $\left( {C=48\% ,N=37.5\% ,S=5\% ,Cl=2.6\% ,Cu=7\% } \right)$, and XRD data identify the crystal structure. Additionally, there is evidence for much smaller crystals in the complex. Detailed data on the microstructure of the materials will be presented and discussed. $^{\mathrm{1}}$L. Ma, W. Chen, G. Schatte, W. Wang, A. G. Joly, Y. Huang, R. Sammyaiken, and M. Hossu, J. Materials Chem., C, \textbf{2}, 4239 (2014) .   

Testing the suitability of a newly engineered smart substrate (VYO4: Er$+$3, Yb$+$3, @Nd$+$3 nanoparticles) for future remote temperature sensing experiments

The progress of biomedical science depends on the availability of tools and instruments capable of analyzing biological systems in their natural environment without disturbing their behavior. Advanced optical characterization techniques, such as Raman spectroscopy, are powerful non-invasive and non-destructive means for obtaining the chemical properties of materials with applications in several fields including agriculture, chemistry, medicine, and materials science. By tailoring the properties of nanomaterials, a wide range of new biomedical applications including remote temperature sensing with existing chemical identification and imaging techniques has become available. I will present the design and outline of the optical system that I helped to develop during this summer. This system tests the suitability of a smart substrate composed of a newly engineered temperature sensitive water-based biocompatible core/shell up-conversion nanoparticle (UCNP) for remote temperature sensing. Future applications of this optical imaging system will be discussed as well.   

Identity as Nexus-of-Multimembership in Physics Learning Assistant Preparation Sessions

The physics department at Texas State University has implemented a Learning Assistant (LA) program in our introductory course sequence in which undergraduate students serve as near-peer assistants in courses they have successfully completed. Many students become LAs while still enrolled in the introductory sequence. We use a blended theoretical framework of Physics Identity and Communities of Practice to examine the impacts of program participation on LAs. Previously we have reported evidence of physics identity development from analysis of interviews with LAs and written reflections. Our data now include video of LAs working together during weekly preparation sessions. We find that during these prep sessions LAs engage in a variety of interactions, including physics-oriented, teaching-oriented, reflective, and social. In this analysis, we examine video episodes for evidence of LAs reconciling forms of membership in multiple communities of practice. ``Identity as nexus of multimembership'' is defined by Wenger (1998) as the ``work of reconciliation necessary to maintain one identity across boundaries.'' In this analysis, we closely examine an episode of LAs navigating the tensions of overlapping roles in student, instructor, and social communities.   

"Using a Mathematical Model to Compare Infection Parameters in Cotton Rats by Age

Respiratory syncytial virus (RSV) is an extremely common viral respiratory infection that currently has no vaccine or treatment. One of the issues in developing a treatment has been that immune system responses in both humans and rats vary in their susceptibility to RSV across different age groups. In this study, we use a mathematical model to quantify the viral kinetics of RSV and analyze its relationship to age. After fitting the model to experimental data, six parameter values were determined and used to calculate the eclipse phase length, infection phase length, basic reproductive number, and infecting time. These values were compared by age and collection site. After running several statistical tests, there was no major trend with the parameter values in relation to either age or collection site. This result provides the foundations for further studies to explore how viral models can better represent RSV and understand the immune response in general.   

Studying the effects of antiarrhythic drugs on restitution properties of action potential duration of canine ventricular cells.

Restitution describes a functional relationship between the action potential duration (APD) and the preceding diastolic interval (DI). It plays an important role in the function of the heart and is believed to determine the stability of heart rhythms. We investigate the effects of various antiarrhythmic drugs on dynamic and standard (S1-S2) restitution properties of APD of ventricular cells by using a canine ventricular cell model. The restitution hypothesis suggests that the slope of the restitution curve governs the transition to alternans, believed to be a precursor to the development of ventricular arrhythmias, particularly ventricular fibrillation (VF). Our study examines the slope of these restitution curves for three classes of drug to determine whether they are proarrhythmic or antiarrhythmic and to test the hypothesis for the prediction of alternans.   

Non-Equilibrium Statistical Physics of Microbes

A non-linear system’s complexity can be measured. The aspiration of this research is a python program that simulates bacterial growth and communicative population density control via quorum sensing and evaluating its time dependence via the Hurst exponent with another python program. A qualitative hypothesis that bacterial population growth as well as virulence are in fact multifractal Brownian processes is to be supported by the Hurst analysis, establishing their stochastic nature to be time variant. Statistical stochastic theory is applied from gathered sources to gage the validity of the program through use of Lotka-Volterra equations and perturbations of the Fokker-Planck equation for multifractal Brownian motion, providing probability density estimates for the population densities at different stages of growth. This simulation is to be used for further development of a generalizable quantitative theory of bacterial growth and order arising from complex systems. Translational probability densities as well as those associated with spatial pattern formation in bacterial cultures will be investigated after that validity of the program is realized and compared to empirical lab data.   

2017 Total Solar Eclipse: Measurement and Analysis

We traveled to Glendo, Wyoming, to observe the 2017 Total Solar Eclipse from the center of the eclipse path. We designed and built remote sensing microcontroller circuits to measure local temperature, pressure, relative humidity, and light intensity throughout the partial and total phases. We then distributed these stand-alone circuits across the eclipse path. We have used our data to determine the speed of the Moon’s shadow, which we compare to theoretical values. We have performed a similar comparison of measured solar brightness versus a theoretical estimate. We also used telescopes and cameras to photograph the eclipse from beginning to end, obtaining images of the Sun’s photosphere, chromosphere, and corona.