Physics Commons^™

Charged Fusion Product Plasma Diagnostics In Spherical Tokamaks, Alexander Netepenko

FIU Electronic Theses and Dissertations

Charged fusion products from the D(d,p)t reaction, protons (p) and tritons (t), can be detected to obtain time and position dependent information on the fusion reaction profile in plasmas heated with neutral particles beams. We have developed a prototype instrument consisting of charged particle detectors with ion-implanted-silicon surface barrier detectors. Each detector is combined with two replaceable collimators in such a way that it can accept protons and tritons emitted from a well-defined area inside the plasma. The detectors thus provide curved views across the plasma volume.

Combining the data of all six detectors allows one to study changes in …

Impact Of Out-Of-Class Science And Engineering Activities On Physics Identity And Career Intentions, Robynne M. Lock, Zahra Hazari, Geoff Potvin

Department of Teaching and Learning

The number of physics bachelor’s degrees that are awarded in the United States annually is small compared to most other science, technology, engineering, and mathematics fields, and only about one-fifth of these degrees are awarded to women. Understanding the influence of students’ science and engineering experiences on career choices is critical in order to improve future efforts to increase the number of physics majors and the participation of women. In this work, we use a physics identity framework to examine the impact of out-of-class science and engineering activities on three identity dimensions and the relationship between these dimensions and physics …

Numerical Determination Of Monopole Scaling Dimension In Parity-Invariant Three-Dimensional Noncompact Qed, Nikhil Karthik, Rajamani Narayanan

Department of Physics

We present a direct Monte Carlo determination of the scaling dimension of a topological defect operator in the infrared fixed point of a three-dimensional interacting quantum field theory. For this, we compute the free energy to introduce the background gauge field of the Q=1 monopole-antimonopole pair in three-dimensional noncompact QED with N=2, 4 and 12 flavors of massless two-component fermions, and study its asymptotic logarithmic dependence on the monopole-antimonopole separation. We estimate the scaling dimension in the N=12 case to be consistent with the large-N (free fermion) value. We find the deviations from this large-N value for N=2 and 4 …

Understanding The Importance Of Graduate Admissions Criteria According To Prospective Graduate Students, Deepa Chari, Geoff Potvin

Department of Physics

Understanding perceptions of graduate admissions from multiple stakeholders can cultivate an improved understanding about the process of graduate induction, the role that admissions plays in restricting diversity in physics, and contribute to more informed practices for all involved. Prior studies in graduate admissions have reported on how certain admission criteria weigh in the consideration of applicants primarily from faculty perspectives. Motivated by the concept of multivocal knowledge, in this article, we report on prospective students’ perspectives of the importance of the same admission criteria—a stakeholder group that is critical but underempowered in the admissions process. We identify a substantial agreement …

Qcd Evolution Of Superfast Quarks, Adam J. Freese, Wim Cosyn, Misak M. Sargsian

Department of Physics

Recent high-precision measurements of nuclear deep inelastic scattering at high x and moderate 6superfast region, in which the momentum fraction of the nucleon carried by its constituent quark is larger than the total fraction of the nucleon at rest, x>1. We derive the leading-order QCD evolution equation for such quarks with the goal of relating the moderate-Q2 data to the two earlier measurements of superfast quark distributions at large 601.1 region is somewhat in the middle of the neutrino-nuclear and muon-nuclear scattering data.

Lz-101, A Novel Derivative Of Danofloxacin, Induces Mitochondrial Apoptosis By Stabilizing Foxo3a Via Blocking Autophagy Flux In Nsclc Cells, Yongjian Guo, Yue Zhao, Yuxin Zhou, Xiaoqing Tang, Zhiyu Li, Xiaotang Wang

Department of Chemistry and Biochemistry

Non-small-cell lung carcinoma (NSCLC) continues to be a vital disease worldwide for its high incidence and consequent mortality rate. In this study, we investigated the anti-cancer effect of LZ-101, a new derivative of danofloxacin, against non-small-cell lung cancer and the underlying mechanisms. In vitro, LZ-101 inhibited the viability of human non-small cell lung cancer cell lines. We demonstrated that LZ-101 induced mitochondrial-mediated apoptosis by increasing Bax/Bcl-2 ratio, loss of mitochondrial membrane potential (ΔΨm), release of cytochrome c (Cyt c) and apoptosis-inducing factor (AIF) in A549 cells. Further research illuminated that LZ-101 induced apoptosis was related to the …

Automated, Efficient, And Accelerated Knowledge Modeling Of The Cognitive Neuroimaging Literature Using The Athena Toolkit, Michael C. Riedel, Taylor P. Salo, Jason Hays, Matthew D. Turner, Matthew T. Sutherland, Jessica A. Turner, Angela Laird

Department of Physics

Neuroimaging research is growing rapidly, providing expansive resources for synthesizing data. However, navigating these dense resources is complicated by the volume of research articles and variety of experimental designs implemented across studies. The advent of machine learning algorithms and text-mining techniques has advanced automated labeling of published articles in biomedical research to alleviate such obstacles. As of yet, a comprehensive examination of document features and classifier techniques for annotating neuroimaging articles has yet to be undertaken. Here, we evaluated which combination of corpus (abstract-only or full-article text), features (bag-of-words or Cognitive Atlas terms), and classifier (Bernoulli naïve Bayes, k-nearest …

Sexual Harassment Reported By Undergraduate Female Physicists, Lauren M. Aycock, Zahra Hazari, Eric Brewe, Kathryn B.H. Clancy, Theodore Hodapp, Renee Michelle Goertzen

Department of Physics

Sexual harassment occurs more frequently in male-dominated fields and physics is a more male-dominated field than most other science, technology, engineering, and mathematics (STEM) fields. Thus, it is important to examine the occurrence and impact of sexual harassment on women in physics. A survey of undergraduate women, who attended a conference for undergraduate women in physics, revealed that approximately three quarters (74.3%; 338/455) of survey respondents experienced at least one type of sexual harassment. This sample was recruited from a large fraction of undergraduate women in physics in the United States. We find that certain types of sexual harassment predict …

Coherent And Incoherent Dynamics Of Quasiparticles In Monolayer Molybdenum Diselenide, Michael Titze

FIU Electronic Theses and Dissertations

Monolayer Materials, especially single-layer graphite, called graphene, as the first synthesized and most prominent representative, have attracted significant research interest since its discovery in 2004. The efforts were rewarded with a Nobel prize in 2010 for the discovery of graphene, the same year in which the first monolayer transition metal dichalcogenide (ML-TMD) was found to have a direct bandgap. In contrast to graphene ML-TMDs have a direct bandgap in the visible or near-infrared spectral range, making them ideally suited for optoelectronic device applications. Explicit inversion symmetry breaking of the unit cell in ML-TMDs furthermore leads to a new interesting property, …