Physical Sciences and Mathematics Commons^™

A High-Altitude Balloon Platform For Determining Regional Uptake Of Carbon Dioxide Over Agricultural Landscapes, Angela M. Bouche

2017 Academic High Altitude Conference

Interactions between the biosphere and atmosphere are an important part of the global carbon cycle, and quantifying the carbon dioxide exchanges between them is helpful in predicting the uptake of carbon dioxide from anthropogenic sources by the biosphere in the future. In the Midwestern United States, agricultural systems cover a large part of the landscape, so understanding their role in influencing the global carbon budget is crucial as anthropogenic sources of carbon dioxide grow larger. Carbon dioxide exchanges can be measured by eddy covariance at the ecosystem level (bottom-up approach) or regionally by inversion techniques (top-down approach). Here we describe …

Detecting Cosmic Rays Using Cemos Sensors In Consumer Devices, Matthew M. Plewa

2017 Academic High Altitude Conference

Since the time of Victor Hess and his balloon flight that demonstrated that cosmic rays increased with altitude, new detection methods have become widely available to be used on current day flights. One such method is to utilize CCDs with long duration exposures. During the exposures the CCD is exposed to cosmic rays which then leave a track. This phenomenon is caused by the CCD's inability to distinguish between photons of light and charged particles. Such tracks can then be separated from the CCD's background noise and classified.

Development Of An Integrated Online Balloon Flight System, Ethan E. Harstad

2017 Academic High Altitude Conference

Aerodyne Labs has been working with the Stratospheric Ballooning Association to develop an all inclusive high altitude ballooning software suite. This software suite is intended to allow every step of conducting a balloon flight to be conducted on a single website. Flight predictions can be performed many days in advance and used to automatically generate notices for both the FAA and public. Once the balloon has been launched, telemetry can be streamed to the website to allow real-time position and telemetry updates, including a dedicated view for FAA controllers. Data that is not streamed from the payload can be uploaded …

Collecting Multiple Data Points In A Thunderstorm Environment, Matthew Nelson

2017 Academic High Altitude Conference

Collecting multiple data points in adverse conditions such as a thunderstorm presents a number of challenges in collecting and relaying data. Wireless sensor mesh networks is a proven method for extracting and relaying data in radio environments that may either be roving, in adverse conditions or both. This paper explores using wireless sensor mesh networks to collect atmospheric data that is present in a thunderstorm system to enable researchers to learn more from these systems. A wireless sensor mesh network is ideal since it is well suited for both moving and sensor nodes that are in adverse RF conditions. A …

Aerobic Copper-Catalyzed O-Methylation With Methylboronic Acid, Clare E. Jacobson, Noella Martinez-Muñoz, David J. Gorin

Chemistry: Faculty Publications

The oxidative coupling of alkylboronic acids with oxygen nucleophiles offers a strategy for replacing toxic, electrophilic alkylating reagents. Although the Chan–Lam reaction has been widely applied in the arylation of heteroatom nucleophiles, O-alkylation with boronic acids is rare. We report a Cu-catalyzed nondecarboxylative methylation of carboxylic acids with methylboronic acid that proceeds in air with no additional oxidant. An isotope-labeling study supports an oxidative cross-coupling mechanism, in analogy to that proposed for Chan–Lam arylation.

Observation Of Charge Asymmetry Dependence Of Pion Elliptic Flow And The Possible Chiral Magnetic Wave In Heavy-Ion Collisions, J. Kevin Adkins, Renee Fatemi, Suvarna Ramachandran, L. Adamczyk, G. Agakishiev, M. M. Aggarwal, Z. Ahammed, I. Alekseev, J. Alford, A. Aparin, D. Arkhipkin, E. C. Aschenauer, G. S. Averichev

Physics and Astronomy Faculty Publications

We present measurements of π⁻ and π⁺ elliptic flow, v₂, at midrapidity in Au+Au collisions at √^S_NN=200, 62.4, 39, 27, 19.6, 11.5, and 7.7 GeV, as a function of event-by-event charge asymmetry, A_ch, based on data from the STAR experiment at RHIC. We find that π⁻ (π⁺) elliptic flow linearly increases (decreases) with charge asymmetry for most centrality bins at √^S_NN=27  GeV and higher. At √^S_NN=200  GeV, the slope of the difference of v₂ between π⁻ and π^{+ …}

The Electronic Structure Of The Pyranopterin Dithiolene Cofactor And Radical Reporters Of Excited State Interactions, Benjamin William Stein

Chemistry and Chemical Biology ETDs

Crystal structures of multiple molybdenum enzymes clearly demonstrate interesting structural distortions involving the pyranopterin dithiolene. These distortions can be correlated with pyranopterin oxidation state through the use of DFT geometry optimized structures of the possible oxidation states, and these are correlated with enzyme family. The potential role of the pyranopterin dithiolene in electron transfer in the varied enzyme familes has been explored through the use of non-equilibrium Green's function (NEGF) electron transport calculations. These calculations demonstrate clear differences in electron transport behavior as a function of pyranopterin oxidation state. The Jahn-Teller effect can strongly impact the geometric and electronic structures …

Synthesis And Characterization Of Conjugated/Cross-Conjugated Benzene-Bridged Boron Difluoride Formazanate Dimers, Stephanie M. Barbon, Jacquelyn T. Price, Umesh Yogarajah, Joe Gilroy

Chemistry Publications

One of the most common strategies for the production of molecular materials with optical properties in the far-red/near-IR regions of the electromagnetic spectrum is their incorporation into dimeric architectures. In this paper, we describe the synthesis and characterization (¹H, ¹¹B, ¹³C and ¹⁹F NMR spectroscopy, IR and UV-Vis absorption and emission spectroscopy, mass spectrometry and X-ray crystallography) of the first examples of boron difluoride (BF₂) formazanate dimers. Specifically, the properties of meta- and para-substituted benzene-bridged dimers p-10 and m-10 were compared to closely related boron difluoride triphenyl formazanate complex …

Using Ion Mobility Spectrometry To Study Protein Conformations In The Gas Phase, Yu Sun

Electronic Thesis and Dissertation Repository

The question whether electrosprayed protein ions retain solution-like conformations remains a matter of debate. One way to address this issue involves comparisons of collision cross sections measured by travelling wave ion mobility spectrometry (TWIMS) with the values calculated for model structures. It is often implied that nanoESI is more conducive for the retention of solution structure than regular ESI. Focusing on four different proteins we demonstrated that collision cross section values and collisional unfolding profiles are virtually indistinguishable under both conditions. Calibration can be challenging because differences in the extent of collisional activation for TWIMS and drift tube calibrant data …

Understanding The Challenges Of Expanding Community Forestry In Northwest Cameroon, Caitlin M. Farnung

FIU Electronic Theses and Dissertations

The tropical afro-montane forest of the Northwest region is unique and under direct threat from the high population density of the region. Community-based forestry management is an opportunity to sustainably manage the remaining forest fragments.

Community forestry was introduced to Cameroon with the legislation of the 1994 Forestry Law. Over two decades later little research has been conducted in the Northwest region of Cameroon. Twenty-four semi-structured interviews were conducted, and samples of forestry records were analyzed as exploratory research that would act as a base for further research.

This research found that the tenure of the community over the community …

公的統計における欠測値補定の研究：多重代入法と単一代入法(高橋将宜), Masayoshi Takahashi

Masayoshi Takahashi

No abstract provided.

Integrating K12 Outreach With Undergraduate & Graduate Student Research Through Balloonsat: High Altitude Balloons, J Tillman Kennon, Bryant Fong

2017 Academic High Altitude Conference

The Arkansas BalloonSAT team has successfully launched and recovered 37 BalloonSAT’s dating back to the first flight on December 16, 2006. Numerous instruments measuring such things as atmospheric temperature, humidity, radiation, and light intensity have recorded data from different locations over the State of Arkansas. The initial focus of this project was outreach with the k-12 schools, and still involves outreach; however atmospheric research has become a significant component for this endeavor. This ongoing collaborative projection has involved a number of faculty and students from different academic backgrounds, including physics, chemistry, biology, and astronomy among different ASGC schools who have …

Directional Camera Control On High Altitude Balloons, Matthew M. Plewa, Brent Scharlau

2017 Academic High Altitude Conference

The research reported in this paper examined the design and control of a gimbal for solar eclipse tracking and video recording. The gimbal design required 3 axes of rotation to allow for full range of motion. Utilizing individual brushless motors for each of the axes ensure minimum rotational requirements on each axes. In controlling the gimbal, both a mathematical and visual method were utilized. The mathematical method is a modified version of what is currently used for solar array pointing. The visual method looks at where the position of the sun is within the image and determines what angle changes …

Using Thermocouple, Thermistor, And Digital Sensors To Characterize The Thermal Wake Below Ascending Weather Balloons, Erick Agrimson, Kaye Smith, Rachel Newman, Kassandra Surma, Maggie Singerhouse, Britany Craig, Marilyn Mcnamara, James Flaten, Alex Pratt, Stephanie Wegner, Joe Dillon

2017 Academic High Altitude Conference

In this paper we present additional results from our on-going research effort to characterize the thermal wake that trails below ascending latex weather balloons on flights into the stratosphere; a wake which interferes with the ability of temperature sensors in payload boxes hanging from the balloon (and hence enveloped by the wake) to correctly measure the ambient temperature of the atmosphere through which the balloon is ascending. A “wake boom” is used to measure temperature variations up to 1.5 m horizontally from varying distances directly below the neck of the balloon. Results to date agree with the literature that especially …

Techniques For Payload Stabilization For Improved Photography During Stratospheric Balloon Flights, James Flaten, Christopher Gosch, Joseph (Benjamin) Habeck

2017 Academic High Altitude Conference

Payload-box rotation and swing are perennial challenges to achieving high-quality photography (typically videography) during weather-balloon flights to “near-space” (AKA the stratosphere). Continuous camera motion can lead to blurred still photos, nearly-impossible-to-watch video footage, and precludes time-exposure photography required for most astronomical imaging even though altitudes are reached where the daytime sky appears black. Apparently-random payload rotation, persisting even at altitude, can often exceed servo rotation rates and frustrate attempts to do active camera pointing. Here we discuss mostly-passive payload stabilization strategies we, and our collaborators, have used to mitigate and dampen both swing and rotation of suspended payloads on high-altitude …

Perturbations Of The Optical Properties Of Mineral Dust Particles By Mixing With Black Carbon: A Numerical Simulation Study, B. V. Scarnato, S. China, K. Nielsen, C. Mazzoleni

Michigan Tech Publications

Field observations show that individual aerosol particles are a complex mixture of a wide variety of species, reflecting different sources and physico-chemical transformations. The impacts of individual aerosol morphology and mixing characteristics on the Earth system are not yet fully understood. Here we present a sensitivity study on climate-relevant aerosols optical properties to various approximations. Based on aerosol samples collected in various geographical locations, we have observationally constrained size, morphology and mixing, and accordingly simulated, using the discrete dipole approximation model (DDSCAT), optical properties of three aerosols types: (1) bare black carbon (BC) aggregates, (2) bare mineral dust, and (3) …

What You Gotta Know To Play Good In The Iterated Prisoner’S Dilemma, Ethan Akin

Publications and Research

For the iterated Prisoner’s Dilemma there exist good strategies which solve the problem when we restrict attention to the long term average payoff. When used by both players, these assure the cooperative payoff for each of them. Neither player can benefit by moving unilaterally to any other strategy, i.e., these provide Nash equilibria. In addition, if a player uses instead an alternative which decreases the opponent’s payoff below the cooperative level, then his own payoff is decreased as well. Thus, if we limit attention to the long term payoff, these strategies effectively stabilize cooperative behavior. The existence of such strategies …

How To Measure Magnetic Flux With A Single Position Measurement?, Eliahu Cohen, Lev Vaidman, Yakir Aharonov

Mathematics, Physics, and Computer Science Faculty Articles and Research

Current methods for measuring magnetic flux are based on performing many measurements over a large ensemble of electrons. We propose a novel method based on wave function "revival" for measuring the flux modulo using only a single electron. A preliminary analysis of the feasibility of the experiment is provided.

Algorithms To Compute Characteristic Classes, Martin Helmer

Electronic Thesis and Dissertation Repository

In this thesis we develop several new algorithms to compute characteristics classes in a variety of settings. In addition to algorithms for the computation of the Euler characteristic, a classical topological invariant, we also give algorithms to compute the Segre class and Chern-Schwartz-MacPherson (CSM) class. These invariants can in turn be used to compute other common invariants such as the Chern-Fulton class (or the Chern class in smooth cases).

We begin with subschemes of a projective space over an algebraically closed field of characteristic zero. In this setting we give effective algorithms to compute the CSM class, Segre class and …

A Spatial And Temporal Analysis Of Land Use And Water Quality In Southern Miami Dade County, Mario Londono

FIU Electronic Theses and Dissertations

This thesis research employs a multi-pronged analysis approach to contribute to the existing knowledge regarding land use and water quality in southern Miami Dade County. Nutrient concentrations for TP, NOx-N, and NH3-N were evaluated for water quality monitoring stations across seven canals for two time periods: 1990-2003 and 2009-2014. Overall, the sites did not surpass the mandated TP threshold but a number of sites exceeded the NOx-N and NH3-N criteria set by multiple government agencies. Statistical tests demonstrated that the sites had differing distributions, not sharing similar median concentrations. Land use classifications were derived for the area interest for the …

Semiparametric Causal Inference In Matched Cohort Studies, Edward Kennedy, Arvid Sjolander, Dylan Small

Edward H. Kennedy

Odds ratios can be estimated in case-control studies using standard logistic regression, ignoring the outcome-dependent sampling. In this paper we discuss an analogous result for treatment effects on the treated in matched cohort studies. Specifically, in studies where a sample of treated subjects is observed along with a separate sample of possibly matched controls, we show that efficient and doubly robust estimators of effects on the treated are computationally equivalent to standard estimators, which ignore the matching and exposure-based sampling. This is not the case for general average effects. We also show that matched cohort studies are often more efficient …

Building An Undergraduate Cohort In High Altitude Ballooning, Mike Davis

2017 Academic High Altitude Conference

City Colleges of Chicago (CCC), in partnership with DePaul University and the Illinois Space Grant Consortium, has recently been awarded a grant from NASA to develop a research and education program in high-altitude ballooning. The project builds on the Chicago Initiative for Research and Recruitment in the Undergraduate Sciences (CIRRUS) model of undergraduate research and community college/four year college collaborative projects, a successful NSF-funded collaboration between DePaul and CCC. The project has four goals: (1) initiate a year-round undergraduate research program to recruit promising community college students into the STEM disciplines, (2) provide tuition support and fellowships to support student …

Nasa Nebraska High Altitude Ballooning And The Fab Lab, Kendra Sibbernsen, Michael Sibbernsen

2017 Academic High Altitude Conference

The NASA Nebraska High Altitude Ballooning (N-NHAB) program has collaborated on projects with the Fab Lab at Metropolitan Community College (MCC) in Omaha, NE. Based on the MIT Center for Bits and Atoms, the Fab Lab contains 3D printers, laser cutters, CNC machines, and much more. In its trial phase, the Fab Lab encouraged projects from the sciences. In response to this request, one of these projects involved a HAB student who wanted to streamline custom circuitry for measuring the efficiency of solar cells. The circuit pathways were designed and precisely cut from a copper sheet and the laser cutter …

Optimization And Simulation Of An Evolving Kidney Paired Donation (Kpd) Program, Yijiang Li, Jack Kalbfleisch, Peter Xuekun Song, Yan Zhou, Alan Leichtman, Michael Rees

Yan Zhou 周彦文档

The old concept of barter exchange has extended to the modern area of living-donor kidney transplantation, where one incompatible donor-candidate pair is matched to another pair with a complementary incompatibility, such that the donor from one pair gives an organ to a compatible candidate in the other pair and vice versa. Kidney paired donation (KPD) programs provide a unique and important platform for living incompatible donor-candidate pairs to exchange organs in order to achieve mutual benefit. We propose a novel approach to organizing kidney exchanges in an evolving KPD program with advantages, including (i) it allows for a more exible …

Set-Based Tests For Genetic Association In Longitudinal Studies, Zihuai He, Min Zhang, Seunggeun Lee, Jennifer A. Smith, Xiuqing Guo, Walter Palmas, Sharon L.R. Kardia, Ana V. Diez Roux, Bhramar Mukherjee

Jennifer McMahon

Genetic association studies with longitudinal markers of chronic diseases (e.g., blood pressure, body mass index) provide a valuable opportunity to explore how genetic variants affect traits over time by utilizing the full trajectory of longitudinal outcomes. Since these traits are likely influenced by the joint eff#11;ect of multiple variants in a gene, a joint analysis of these variants considering linkage disequilibrium (LD) may help to explain additional phenotypic variation. In this article, we propose a longitudinal genetic random field model (LGRF), to test the association between a phenotype measured repeatedly during the course of an observational study and a set …

Day 1: Wednesday, 17 August 2005: Biodiversity And Critical Habitat, Charles Bedford, Federico Cheever, Tim Sullivan

Tim Sullivan

6 pages (includes color illustration). Contains references.

Biological, Clinical, And Forensic Analysis Using Comprehensive Two-Dimensional Gas Chromatography, Nicholas Snow

Nicholas A Snow

No abstract provided.

Novel Techniques For Enhancing Sensitivity In Static Headspace, Nicholas Snow, G.P Bullock

Nicholas A Snow

No abstract provided.

Simultaneous Determination Of Pramoxine Hcl And Benzalkonium Chloride In Wound Care Solutions By Hplc, Panagiotis Tavlarakis, Jonine Greyling, Nicholas Snow

Nicholas A Snow

No abstract provided.

Convergence Properties Of Harmonic Measure Distributions For Planar Domains, Maria Snpes

Maria Snipes

We establish sufficient conditions under which the harmonic measure distribution functionsh_n of a sequence of domains D_n converge pointwise to the distribution function h of the limiting domain D, at all points of continuity of h. In the case of a model example, we establish this convergence of the distribution functions. Here, the value of the function h(r) gives the harmonic measure of the part of the boundary of the domain that lies within distance r of a fixed basepoint in the domain, thus relating the geometry of the domain to the …