3,060 research outputs found
The quantization of exotic states in SU(3) soliton models: A solvable quantum mechanical analog
The distinction between the rigid rotor and Callan-Klebanov approaches to the
quantization of SU(3) solitons is considered in the context of exotic baryons.
A numerically tractable quantum mechanical analog system is introduced to test
the reliability of the two quantization schemes. We find that in the equivalent
of the large N_c limit of QCD, the Callan-Klebanov approach agrees with a
numerical solution of the quantum mechanical analog. Rigid rotor quantization
generally does not. The implications for exotic baryons are briefly discussed.Comment: 8 pages; 3 figures; minor corrections; reference adde
Pricing Bodies: A Feminist New Materialist Approach to the Relations Between the Economic and Socio-Cultural
Arguments that the economic and socio-cultural should be understood as relational and intertwined, and that price involves a reciprocal relationship between the economic and socio-cultural, are increasingly prevalent in the social sciences. I develop these notions of relationality and reciprocation through a feminist new materialist perspective, which emphasises the entanglement of and intra-action between what might usually be seen as independent and autonomous entities. To do this, I focus on a range of recent body-image initiatives, led by government, corporate and non-profit organisations, which aim to improve girls’ and young women’s levels of confidence and self-esteem. I explore how feminist theory tends to see such initiatives in terms of the expansion of the economic sphere into the socio-cultural, which involves a tainting or contamination of embodiment and feeling. Rather than dispute these arguments, I take seriously theories and practices from cultural economy that see the economic and socio-cultural as co-constitutive. I augment these ideas with a feminist new materialist approach and argue that the economic and socio-cultural are in intra-active relations: they do not precede or exist apart from each other. In doing so, I consider how body-image initiatives can be understood as phenomena produced through these entangled intra-active relations, and offer an understanding of pricing as a simultaneously socio-cultural and economic process, where value and values become. I also raise questions regarding how, ethically and politically, boundary making and unmaking can be conceived, and how despite being in entangled relations, asymmetries between economic and socio-cultural relations may be approached
Exploring the Impact of Early Exposure to Research on Dual Enrollment Students: A Qualitative Single-Case Study
Embry-Riddle Aeronautical University (ERAU) provides a concurrent enrollment model to high schools across the United States. The concurrent enrollment opportunity offers science, technology, engineering, and mathematics (STEM) college-credit coursework taught by college-credentialed instructors on the student’s high school campus. One faculty member transitioned to Embry-Riddle’s main residential campus following seven years of service with ERAU’s concurrent enrollment program. During his tenure with ERAU’s concurrent enrollment program, in addition to instructing a variety of concurrent enrollment courses, he maintained an active research agenda that involved concurrently enrolled students. His transition was preceded by the matriculation of a subset of these students to Embry-Riddle’s main campus. Each of these students immediately reengaged in undergraduate research with the faculty member while he continued to serve in a strong mentoring role. This presentation explores the affect this opportunity had on individual members of this tight-knit cohort as they progressed through their concurrent enrollment and undergraduate studies, participated in a long-standing mentoring relationship, and undertook their post-graduation decision-making. The research showcases project-based learning as a scaffolding technique for meaningful undergraduate research and how it may illuminate a pathway for students who do not initially see STEM as a viable option
A Qualitative Single-Case Exploring the Impact of a Mentor and Cohort on Students’ Academic and Career Decisions.
Exposure to research is known to play a positive role in undergraduate education. However, robust research responsibilities are oftentimes not formally incorporated into a student’s academic experience until master level studies. Further, a variety of intimidation factors often inhibit many undergraduate students from participating on a research team. In this case study, the research team evaluated a unique group of undergraduate researchers who matriculated to the same university after beginning to participate in research as concurrently enrolled students. Following matriculation, each student continued to participate in research throughout the entirety of their undergraduate studies. All of the study’s students were STEM majors and undertook this research, both prior to and following matriculation, in the same lab and under the same mentor. This arrangement removed many of the common barriers to students participating in undergraduate research, such as the intimidation of working with strangers, including graduate students, and unclear expectations for undergraduate lab students from faculty. Consequently, the unique circumstance presented in this work affords the opportunity to more fully explore the influence that a strong longterm mentor and extended participation in research have on students’ post-graduate decision making
Slow relaxation of conductance of amorphous hopping insulators
We discuss memory effects in the conductance of hopping insulators due to
slow rearrangements of structural defects leading to formation of polarons
close to the electron hopping states. An abrupt change in the gate voltage and
corresponding shift of the chemical potential change populations of the hopping
sites, which then slowly relax due to rearrangements of structural defects. As
a result, the density of hopping states becomes time dependent on a scale
relevant to rearrangement of the structural defects leading to the excess time
dependent conductivity.Comment: 6 pages, 1 figur
Heat transfer between nanoparticles: Thermal conductance for near-field interactions
We analyze the heat transfer between two nanoparticles separated by a
distance lying in the near-field domain in which energy interchange is due to
Coulomb interactions. The thermal conductance is computed by assuming that the
particles have charge distributions characterized by fluctuating multipole
moments in equilibrium with heat baths at two different temperatures. This
quantity follows from the fluctuation-dissipation theorem (FDT) for the
fluctuations of the multipolar moments. We compare the behavior of the
conductance as a function of the distance between the particles with the result
obtained by means of molecular dynamics simulations. The formalism proposed
enables us to provide a comprehensive explanation of the marked growth of the
conductance when decreasing the distance between the nanoparticles
Energy Dependence of Moments of Net-Proton Multiplicity Distributions at RHIC
We report the beam energy (√ˢᴺᴺ = 7.7-200 GeV) and collision centrality dependence of the mean (M), standard deviation (σ), skewness (S), and kurtosis (κ) of the net-proton multiplicity distributions in Au + Au collisions. The measurements are carried out by the STAR experiment at midrapidity (|y| \u3c 0.5) and within the transverse momentum range 0.4 \u3c pT \u3c 0.8 GeV/c in the first phase of the Beam Energy Scan program at the Relativistic Heavy Ion Collider. These measurements are important for understanding the quantum chromodynamic phase diagram. The products of the moments, Sσ and Kσ2, are sensitive to the correlation length of the hot and dense medium created in the collisions and are related to the ratios of baryon number susceptibilities of corresponding orders. The products of moments are found to have values significantly below the Skellam expectation and close to expectations based on independent proton and antiproton production. The measurements are compared to a transport model calculation to understand the effect of acceptance and baryon number conservation and also to a hadron resonance gas model
Beam Energy Dependence of Moments of the Net-Charge Multiplicity Distributions in Au + Au Collisions at RHIC
We report the first measurements of the moments-mean (M), variance (σ2), skewness (S), and kurtosis (κ)-of the net-charge multiplicity distributions at midrapidity in Au + Au collisions at seven energies, ranging from √ˢᶰᶰ = 7.7 to 200 GeV, as a part of the Beam Energy Scan program at RHIC. The moments are related to the thermodynamic susceptibilities of net charge, and are sensitive to the location of the QCD critical point. We compare the products of the moments, σ2/M, Sσ, and κσ2, with the expectations from Poisson and negative binomial distributions (NBDs). The Sσ values deviate from the Poisson baseline and are close to the NBD baseline, while the κσ2 values tend to lie between the two. Within the present uncertainties, our data do not show nonmonotonic behavior as a function of collision energy. These measurements provide a valuable tool to extract the freeze-out parameters in heavy-ion collisions by comparing with theoretical models. © American Physical Societ
Dielectron Mass Spectra from Au plus Au Collisions at √ˢᴺᴺ = 200 GeV
We report the STAR measurements of dielectron (e+e-) production at midrapidity ( |yee| \u3c 1) in Au + Au collisions at √ˢᴺᴺ = 200 GeV. The measurements are evaluated in different invariant mass regions with a focus on 0.30-0.76 (ρ-like), 0.76-0.80 (ω-like), and 0.98-1.05 (ɸ-like) GeV/c2. The spectrum in the ω-like and ɸ-like regions can be well described by the hadronic cocktail simulation. In the ρ-like region, however, the vacuum ρ spectral function cannot describe the shape of the dielectron excess. In this range, an enhancement of 1.77 ±0.11(stat) ± 0.24(syst) ± 0.33(cocktail) is determined with respect to the hadronic cocktail simulation that excludes the ρ meson. The excess yield in the ρ-like region increases with the number of collision participants faster than the ω and ɸ yields. Theoretical models with broadened rho contributions through interactions with constituents in the hot QCD medium provide a consistent description of the dilepton mass spectra for the measurement presented here and the earlier data at the Super Proton Synchrotron energies
Oral cavity squamous cell carcinoma xenografts retain complex genotypes and intertumor molecular heterogeneity
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