- Ph.D defense: H I Kinematics and Star Formation Rate in LITTLE THINGS Galaxies
Nov. 8, 2016, 10am-11am, CP 220
Nau Raj Pokhrel will be defending his doctoral dissertation in the field of Astronomy. Dr. Simpson is his adviser.
We present a catalog and analysis of the properties of neutral hydrogen gas (
H I) holes/shells in the LITTLE THINGS (Local Irregulars That Trace Luminosity Extremes, The H I Nearby Galaxy Survey) galaxies. LITTLE THINGS uses high angular resolution (6''), high spectral resolution (≤ 2.6 km s–1), and high sensitivity (≤ 1.1 mJy beam–1 channel–1) H Iobservations of 41 nearby (≤ 10.3 Mpc) gas-rich dwarf galaxies. Dwarf galaxies are the most common type of galaxy in the local universe and they are believed to be the first galaxies to form. Here we study the interaction between star formation and the interstellar medium from which stars form. In the sample of galaxies, we detected 306 H I holes with sizes ranging from about 38 pc to 2.3 kpc, expansion rates varying from 5 to 30 km s–1, and estimated kinetic ages varying from 1 Myr to 127 Myr. The distribution of holes per unit area is found nearly constant both inside (51%) and outside (49%) of the V-band break radius, where the radial luminosity function changes slope. We derived surface and volume porosity and found that porosity doesn't correlate with star formation rate (SFR) for the LITTLE THINGS sample. Assuming that the holes are formed from the stellar feedback, we calculated the supernova rate (SNR) and the SFR. We did find a correlation between the SFR calculated from Hα (a star formation tracer) and the SFR estimated from the SNR, consistent with hole formation from stellar feedback.
- Ph.D defense: Two Dimensional Lattice Gauge Theory with and without Fermion Content
Nov. 3, 2016, 10am-12pm, CP 220
DibikarSigdel will defend his doctoral dissertation in the field of Theoretical Nuclear Physics. His adviser is Dr. Narayanan.
Quantum Chromo Dynamics (QCD) is a relativistic field theory of a non-abelian gauge field coupled to several flavors of fermions. Two dimensional (one space and one time) QCD serves as an interesting toy model that shares several features with the
four dimensionalphysically relevant theory .Themain aim of the research is to study two dimensional QCD using the lattice regularization.
Two dimensional QCD without any fermion content is solved analytically using lattice regularization. Explicit expressions for the expectation values of Wilson loops and the correlation of two Polyakov loops oriented in two different directions are obtained. Physics of the QCD vacuum is explained using these results.
The Hamiltonian formalism of lattice QCD with fermion content serves as an approach to study quark excitations out of the vacuum. The formalism is first developed and techniques to numerically evaluate the spectrum of physical particles, namely, meson and baryons are described. The Hybrid Monte Carlo technique was used to numerically extract the lowest meson and baryon masses as a function of the quark masses. It is shown that neither the lowest meson mass nor the lowest baryon mass goes to zero as the quark mass is taken to zero. This numerically establishes the presence of a mass gap in two dimensional QCD.
- Ph.D defense: Rate Kinetics and Molecular Dynamics of the Structural Transitions in Amyloidogenic Pr
Oct. 19, 2016, 1:30pm-2:30pm, CP 220
Tim Steckmann will defend his doctoral dissertation in the field of Computational
Bio-physics. His adviser is Dr. Gerstman.
Amyloid fibril aggregation is associated with several horrific diseases such as Alzheimer’s, Creutzfeld-Jacob, diabetes, Parkinson’s and others. This dissertation explores how hydrogen bonds break and form and the heterogeneity of amyloid-forming systems.
Amyloid fibrils are composed of proteins that originate in innocuous structure. On the basis of experimental data, I have developed a mathematical model for the population kinetics of the reaction pathways and determined rate parameters for protein structural conversion and aggregation during the entire fibrillogenesis process, including the molecular species that accelerate the conversions. To better understand the molecular basis of the protein structural transitions and aggregation, I report on molecular dynamics (MD) computational studies on the formation of amyloid
protofibrillarstructures in the small model protein ccβ, which undergoes many of the structural transitions of the larger, naturally occurring amyloid formingproteins. Two different structural transition processes involving hydrogen bonds are observed for aggregation into fibrils: the breaking of intrachain hydrogen bonds to allow β-hairpin proteins to straighten, and the subsequent formation of interchain hydrogen bonds during aggregation into amyloid fibrils. Both the mathematical modeling of the population kinetics and the MD simulations show that molecular structural heterogeneity is a major factor in the process. The MD simulations also show that intrachain and interchain hydrogen bonds breaking and forming is strongly correlated to the process of amyloid formation.
- Ph.D Defense: Role of Students’ Participation on Learning Physics in Active Learning Classes
Oct. 10, 2016, 11am-12pm, PG 6 112
Binod Nainabasti will defend his Doctoral Dissertation in the field of Physics Education. His adviser is Dr. Eric Brewe from the STEM
Students’ interactions can be an influential component of students’ success in an interactive learning environment. From a participation perspective, learning is viewed in terms of how students transform their participation. However, many of the seminal papers discussing the
participationistframework are vague on specific details about what student participation really looks like on a more fine-grained scale. As part of a larger project to understand the role of student participation in learning, this study has gathered data that quantified students’ participation in three broad areas of two student-centered introductory calculus-based physics classes structured around the Investigative Science Learning Environment (ISLE) philosophy.
Those three broad areas of classes were in-class learning activities, class review sessions that happened at the beginning of every class, and the informal learning community that formed outside of class time. Using video data, classroom observations, and students’ self-reported social network data, this study quantified students’ participation in these three aspects of the class throughout the two semesters. The relationship between behaviors of students’ engagement in various settings of an active learning environment and (a) their conceptual understanding (measured by FCI gain) and (b) academic success in the courses as measured by exam scores and scores on out-of-class assignments were investigated.
The results revealed that students’ interaction in the learning process
haveshown that three class components: the Review Session, Learning Activities, and Informal Learning Community, play distinct roles in learning. Students who come in class with better content knowledge do not necessarily participate more in the learning activities of active learning classrooms. Learning Communities serve as a “support network” for students to finish assignments and help students to pass the course. Group discussions, which are facilitated by students themselves, better help students in gaining conceptual understanding. Since patterns of students’ participation do not change significantly over time, instructors should try to ensure greater participation by incorporating different learning activities in the active learning classroom.
- Key West Style Star Party
July 15, 2016, 8pm-11:30pm, Stocker AstroScience Center and CP 145
See Jupiter, Mars
andSaturn at the best party on the planet and tour the starship bridge!
- Curious Vault Collaborations
July 6, 2016, 10am-5pm, Patricia & Phillip Frost Art Museum
Art and science come together in Neural Networks. The exhibit and video showcase the collaboration of two FIU faculty - neuroscientist Angie Laird and multimedia artist Felice Grodin.
- Neural Networks panel discussion and exhibit at the Frost Art Museum
June 18, 2016, 6pm-8pm, Frost Art Museum
The Patricia and Phillip Frost Art Museum will host the third installment of Curious Vault Collaborations: Neural Networks. The event explores the pathways of the human brain via Cognitive Neuroimaging and includes a moderated panel discussion on the merging of art and science with physics professor Angie Laird and others.
Curious Vault Collaborations 003 - Neural Networks
Opening Reception from 6-7pm | Moderated Discussion from 7-8pm
The Patricia and Phillip Frost Museum of Science will host the third installment of Curious Vault Collaborations, a project which partners a local artist and scientist together to create a tabletop exhibit display using at least one item from the Frost Science collection, followed by a moderated panel discussion about the exhibit.
The upcoming installation, Curious Vault Collaborations 003, is entitled Neural Networks and will explore the pathways of the human brain via Cognitive Neuroimaging. The event will serve as the debut of the installation at the Frost Art Museum and include a moderated discussion on the merging of art and science, along with an inside look at the project making of Neural Networks, featuring Bookleggers founder and writer Nathaniel Sandler; Kevin Arrow, art & collection manager for Frost Science; along with Neural Networks creators, artist and Adjunct Professor of Architecture at Florida International University; Felice Grodin; Associate Professor of Physics at Florida International University, Dr. Angela Laird; and BYO-Lab co-founder, Andrea
Neural Networks will be on display at the Frost Art Museum through August 12.
- Search Committee Meeting: BSI Open Rank Faculty Position # 70029763 - Jan. 12
Jan. 12, 2016, 3pm-6pm, AHC4 401
The search committee for the BSI open rank faculty position will meet on Tuesday, Jan. 12, 2016, AHC4-401,
- Search Committee Meeting: BSI Open Rank Faculty Position # 70029763 - Jan. 5
Jan. 5, 2016, 1pm-3pm, AHC4 402
The search committee for the BSI open rank faculty position will meet on Tuesday, Jan. 5, 2016, AHC4-402,