cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
title: Dynamics of nanoparticles and bubbles in creeping flows of viscous fluids
Creators: name: Hassan, Hassan Kiream
Publisher: name: University of Southern Queensland
Year: 2018
Subjects: subject: 010299 Applied Mathematics not elsewhere classified

description: This research deals with the study of dynamics of nanoparticles and bubbles in creeping flows of viscous fluids. The study was based on theoretical approaches and numerical methods. To conduct numerical simulations, the original FORTRAN codes were developed and realised on a desktop computer. To process the obtained results the Mathcad software was actively used. Firstly, the dynamics of two unlike and like charged particles in viscous fluid in the creeping flow approximation was studied. Two types and different models of viscous drag forces were taken into consideration. The particles’ trajectories under the influence of all these forces were studied and compared with those immersed in inviscid fluid. Next, the complex dynamics of small rigid particles under the influence of acoustic radiation force were considered. Our analysis was based on a more advanced model in comparison with those used in the earlier works (Sarvazyan & Ostrovsky, 2009; Ostrovsky, 2015). In addition to the Stokes drag force, the model used in this study included particle inertia, added mass effect, and the Boussinesq–Basset drag force, the effects of these were ignored in the cited papers. It has been shown through numerical solutions that all of these additional effects can be important at some stages of particle motion, whereas in other stages they can be neglected. The particle motion was considered both for the plane and cylindrical geometries. An interesting and prospective method of particle control in a fluid was studied by periodic switching of the acoustic modes in a resonator. In the last Chapter there is an analysis of the influence of memory integral drag forces on the resonance characteristics of oscillating solid particles and gaseous bubbles in a viscous fluid under the influence of an external sinusoidal force. It has been shown that the memory integral drag forces lead to the widening of resonance curves and the reduction of resonance peaks, so that the effective quality of oscillator significantly decreases in comparison with the similar oscillator with only Stokes drag force.
Full-field hard x-ray microscopy with interdigitated silicon lenses
Creators: name: Simons, Hugh
name: Stöhr, Frederik
name: Michael-Lindhard, Jonas
name: Jensen, Flemming
name: Hansen, Ole
name: Detlefs, Carsten
name: Poulsen, Henning Friis
Publisher: name: arXiv
Year: 2015
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: Full-field x-ray microscopy using x-ray objectives has become a mainstay of the biological and materials sciences. However, the inefficiency of existing objectives at x-ray energies above 15 keV has limited the technique to weakly absorbing or two-dimensional (2D) samples. Here, we show that significant gains in numerical aperture and spatial resolution may be possible at hard x-ray energies by using silicon-based optics comprising 'interdigitated' refractive silicon lenslets that alternate their focus between the horizontal and vertical directions. By capitalizing on the nano-manufacturing processes available to silicon, we show that it is possible to overcome the inherent inefficiencies of silicon-based optics and interdigitated geometries. As a proof-of-concept of Si-based interdigitated objectives, we demonstrate a prototype interdigitated lens with a resolution of ~255 nm at 17 keV.
description: 10 pages, 5 figure. Submitted to Applied Physics Letters 31st March 2015, rejected 17th June 2015
Soft dipole resonance in $^8$C and its isospin symmetry with $^8$He
Creators: name: Myo, Takayuki
name: Kato, Kiyoshi
Publisher: name: arXiv
Year: 2023
Subjects: subject: Nuclear Theory (nucl-th)
subject: Nuclear Experiment (nucl-ex)
subject: FOS: Physical sciences

description: We investigate the soft dipole resonance in the proton-rich nucleus $^8_6$C$_2$, which is a collective dipole oscillation of four valence protons against the $α$ core,and discuss the isospin symmetry with the mirror nucleus $^8_2$He$_6$. We use the $α+N+N+N+N$ five-body cluster model and many-body resonances are obtained using the complex-scaling method. The $1^-$ resonance of $^8_6$C$_2$ is confirmed at the excitation energy of 13 MeV with a large decay width of 24 MeV, and its structure is similar to the soft dipole resonance in $^8_2$He$_6$, such as the configuration mixing and the spatial properties. These results indicate a good isospin symmetry in the soft dipole resonances of two nuclei with a common collective excitation of multiproton and multineutron, while the ground states of two nuclei show different properties due to the Coulomb repulsion of valence protons in $^8_6$C$_2$, leading to the symmetry breaking. In conclusion, the appearance of the isospin symmetry differs depending on the states of $^8_6$C$_2$ and $^8_2$He$_6$.
description: 7 pages, 4 figures
Necesitamos Hablar: A Review of the Literature Addressing Type 2 Diabetes and Hispanic Adolescents
Creators: name: Cazales, Andrea
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2019

description: Type 2 diabetes mellitus, previously considered an adult disease, has emerged as a significant health issue in the pediatric population. According to the National Health and Nutrition Examination Survey (NHANES), Hispanic/Latino (Hispanic) adolescents aged 12 to 19 years exhibit higher rates of overweight and obesity among youth of all ages and ethnic groups. Hispanic adolescents experience greater health disparities and an increased risk for developing diabetes. Method: A search of the literature using PubMed and PsycINFO focused on interventions that targeted diabetes risk reduction interventions reporting adiposity, glucose and insulin levels, nutrition education, strength training, and physical activity outcomes in overweight and/or obese Hispanic adolescents. Twelve studies met the inclusion criteria and confirmed that there was minimal evidence of the impact on diabetes prevention interventions targeting Hispanic adolescents. Future research should focus on culturally tailored efficacy and effectiveness trials with larger sample sizes, increased intervention length, and improved and delivery modalities to improve retention.
Spatio-Temporal driven Attention Graph Neural Network with Block Adjacency matrix (STAG-NN-BA)
Creators: name: Nazir, U.
name: Islam, W.
name: Taj, M.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: FOS: Computer and information sciences

description: Despite the recent advances in deep neural networks, standard convolutional kernels limit the applications of these networks to the Euclidean domain only. Considering the geodesic nature of the measurement of the earth's surface, remote sensing is one such area that can benefit from non-Euclidean and spherical domains. For this purpose, we propose a novel Graph Neural Network architecture for spatial and spatio-temporal classification using satellite imagery. We propose a hybrid attention method to learn the relative importance of irregular neighbors in remote sensing data. Instead of classifying each pixel, we propose a method based on Simple Linear Iterative Clustering (SLIC) image segmentation and Graph Attention GAT. The superpixels obtained from SLIC become the nodes of our Graph Convolution Network (GCN). We then construct a region adjacency graph (RAG) where each superpixel is connected to every other adjacent superpixel in the image, enabling information to propagate globally. Finally, we propose a Spatially driven Attention Graph Neural Network (SAG-NN) to classify each RAG. We also propose an extension to our SAG-NN for spatio-temporal data. Unlike regular grids of pixels in images, superpixels are irregular in nature and cannot be used to create spatio-temporal graphs. We introduce temporal bias by combining unconnected RAGs from each image into one supergraph. This is achieved by introducing block adjacency matrices resulting in novel Spatio-Temporal driven Attention Graph Neural Network with Block Adjacency matrix (STAG-NN-BA). We evaluate our proposed methods on two remote sensing datasets namely Asia14 and C2D2. In comparison with both non-graph and graph-based approaches our SAG-NN and STAG-NN-BA achieved superior accuracy on all the datasets while incurring less computation cost. The code and dataset will be made public via our GitHub repository.
Quantum ergodicity for quantum graphs without back-scattering
Creators: name: Brammall, Matthew
name: Winn, Brian
Publisher: name: arXiv
Year: 2015
Subjects: subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences
subject: 81Q35, 34L20

description: We give an estimate of the quantum variance for $d$-regular graphs quantised with boundary scattering matrices that prohibit back-scattering. For families of graphs that are expanders, with few short cycles, our estimate leads to quantum ergodicity for these families of graphs. Our proof is based on a uniform control of an associated random walk on the bonds of the graph. We show that recent constructions of Ramanujan graphs, and asymptotically almost surely, random $d$-regular graphs, satisfy the necessary conditions to conclude that quantum ergodicity holds.
description: 28 pages, 5 figures
The Performance of Technology in Flipped Classrooms for Foreign English Language learners in a Writing Production Course at Universidad Técnica Nacional, San Carlos.
Creators: name: López, Michelle Ramírez
Publisher: name: Zenodo
Year: 2021
Subjects: Flipped classroom, Technology, Foreign Language, Writing techniques

description: This case study explores the Performance of Technology in flipped classrooms for foreign English language learners in a writing production course at Universidad Técnica Nacional, San Carlos. This research studied the effects on learners when it comes to writing production. Moreover, it provides proposals for teachers effectively implement the flipped class by using technology. From the qualitative perspective, the methodology includes two stages for the data collection in which applies one interview, and one survey in order to obtain the insight regarding their performance and perception of the flipped classroom approach in which the finding reveal the positiveness of the Flipped method. Finally, conclusions and recommendations provide information that can help tutors to understand the effects of this approach in young English learners for studying writing production.
Natural orbitals renormalization group approach to a spin-1/2 impurity interacting with two helical liquids
Creators: name: Zheng, Ru
name: He, Rong-Qiang
name: Lu, Zhong-Yi
Publisher: name: arXiv
Year: 2023
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: Using the natural orbitals renormalization group, we studied the problem of a localized spin- 1/2 impurity coupled to two helical liquids via the Kondo interaction in a quantum spin Hall insulator, based on the Kane-Mele model defined in a finite zigzag graphene nanoribbon. We investigated the influence of the Kondo couplings with the helical liquids on both the static and dynamic properties of the ground state. The number and distinct spatial structures of the active natural orbitals (ANOs), which play essential roles in constructing the ground-state wave function, were first analyzed. Our numerical results indicate that two ANOs emerge, equal to the number of helical liquids. Specifically, at the coupling symmetry point, both ANOs are fully active with their spatial structures being respectively constituted by the different helical liquids. In comparison, when deviating from the symmetry point, only one ANO remains fully active, which is dominantly constructed by the helical liquid with the larger Kondo coupling. Local screening of the impurity, described by the impurity spin polarization and susceptibility, was further studied. It shows that at the coupling symmetry point, the impurity is maximally polarized and the spin susceptibility reaches the maximum. On the contrary, the impurity tends to be screened without polarization when the Kondo couplings deviate well from the symmetry point. The Kondo screening cloud, manifested by the spin correlation between the impurity and the conduction electrons, was finally explored. It is demonstrated that the Kondo cloud is mainly formed by the helical liquid with the larger Kondo coupling to the impurity. On the other hand, the spin-orbital coupling breaks the symmetry in spatial distribution of the spin correlation, leading to anisotropy in the Kondo cloud.
Probing crystallinity of graphene samples via the vibrational density of states
Creators: name: Jain, Sandeep K.
name: Juricic, Vladimir
name: Barkema, Gerard T.
Publisher: name: arXiv
Year: 2015
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: The purity of graphene samples is of crucial importance for their experimental and practical use. In this regard, the detection of the defects is of direct relevance. Here, we show that structural defects in graphene samples give rise to clear signals in the vibrational density of states (VDOS) at the specific peaks at high and low frequencies.These can be used as an independent probe of the defect density. In particular, we consider grain boundaries made of pentagon-heptagon pairs, and show that they lead to a shift of the characteristic vibrational D mode towards higher frequency; this distinguishes these line defects from the Stone-Wales point defects, which do not lead to such a shift. Our findings may be instrumental for the detection of structural lattice defects using experimental techniques that can directly measure VDOS, such as inelastic electron tunneling and inelastic neutron spectroscopy.
Modeling the Asteroseismic Surface Term across the HR Diagram
Creators: name: Schmitt, Joseph R.
name: Basu, Sarbani
Publisher: name: arXiv
Year: 2015
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Asteroseismology is a powerful tool that can precisely characterize the mass, radius, and other properties of field stars. However, our inability to properly model the near-surface layers of stars creates a frequency-dependent frequency difference between the observed and the modeled frequencies, usually referred to as the "surface term". This surface term can add significant errors to the derived stellar properties unless removed properly. In this paper we simulate surface terms across a significant portion of the HR diagram, exploring four different masses ($M=0.8, 1.0, 1.2$, and $1.5$ M$_\odot$) at five metallicities ($[\rm{Fe/H}]=0.5, 0.0, -0.5 ,-1.0, and -1.5$) from main sequence to red giants for stars with $T_{\rm{eff}}<6500 K$ and explore how well the most common ways of fitting and removing the surface term actually perform. We find that the two-term model proposed by Ball & Gizon (2014) works much better than other models across a large portion of the HR diagram, including the red giants, leading us to recommend its use for future asteroseismic analyses.
description: Accepted to ApJ. 18 figures
Bound-State Formation of Quantum Many-Flavor Systems: The Divergence of the Critical Coupling
Creators: name: Blanton, Tyler
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2016

description: When multiple quantum particles of different species - or "flavors" - are allowed to interact via pairwise interactions, they may form bound states. If these interactions can be modeled by an attractive contact potential, the strength of the attractions will depend on a single parameter: the coupling g. In 3D, when two or more flavors are present, it is possible for the system to form a bound state if the coupling is above a certain finite threshold g[c]. In contrast, a one-flavor system is just a free particle and can only exist in scattering states (i.e., g[c] = ∞). Although non-integer flavor numbers N[f] have no obvious physical meaning, they are mathematically valid and can be used to examine the analytic relationship between N[f] and g[c]. We used computational methods to vary N[f] in the continuum interval (1,2] in an effort to determine the manner in which g[c] → ∞ as N[f] → 1+. We used Fortran and Python to calculate many-body quantum systems with parameters N[f] and g. Specifically, we used the projection Monte Carlo method to calculate the ground-state energies E[0] of these systems. Plotting E[0] vs. g, we obtained the critical coupling g[c] at which bound state formation occurred for each N[f] sampled. Determining the manner in which g[c] diverges sees applications in theoretical fields such as QCD - where similar problems related to flavor number arise in the study of quarks - as well as in the experimental study of ultracold
atoms, where the quantum simulation of increasingly arbitrary systems is becoming a
reality.
Women's Relationships in Sappho's Poetry
Creators: name: Kubic, Amanda
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2016

description: Sappho’s poetry has been the subject of much scholarship and speculation from antiquity up to the present day. Various theories about her role in society, poetic voice and persona, and sexual orientation have been suggested among classicists, poets, and feminist scholars, yet she and her work remain elusive. Much remains to be understood, not least because many of these studies have applied post-classical concepts and models to the anomalous fact and nature of her poetry. In particular, the subject of women’s relationships in Sappho deserves both greater attention and a more nuanced approach. Both female friendships and female sexual or erotic relationships are central features of her poetry. While scholarship has examined some of the different features of female relationships in Sappho’s work, further study of their context, the forms that they took, and their meaning to the women who participated in them, is needed. My aim in this thesis is to understand these female relationships in terms of archaic and ancient Greek culture, drawing on what is known about women’s religion and oral poetry instead of using post-antique models that project modern constructs and institutions onto ancient attitudes and behaviors. I will argue here that female religious rituals offered Greek women opportunities for important, meaningful relationships and activities, and that they provide a crucial context for the female relationships found in Sappho’s poetry.
Push button reproduction attempt of a research claim from Liang, J., Wang, H., & Lazear, E. P. (2018) in Journal of Political Economy
Creators: name: Talbert, Eli
Publisher: name: Open Science Framework
Year: 2022
Subjects: subject: Social and Behavioral Sciences

description: The number of entrepreneurs as a fraction of the workforce decreases with the country’s median age. This reflects the following statement from the paper's abstract: "A one standard deviation decrease in a country’s median age increases new business formation by 2.5 percentage points, which is about 40 percent of the mean rate." [Tested with] country-Year-Level entrepreneurship rate regression. Table 2 reports reduced-form regressions at the country level of aggregation. Portion of Table 2 selected is Column 3. Focal independent variable is “Median age (ages 20-64)”. [Coefficient of “Median age (ages 20-64)” is -0.007 with standard errors clustered at the country level of -0.001, significant at 1 percent.] Using the estimates from column 3 of table 2, a one standard deviation decrease in median age (equal to 3.5 years in 2010) results in a 2.5 percentage point increase in the entrepreneurship rate, which is over 40 percent of the mean entrepreneurship rate across countries (equal to 0.061 in 2010). The focal test in the original paper is: [Coefficient of “Median age (ages 20-64)” is -0.007 with standard errors clustered at the country level of -0.001, significant at 1 percent.] Using the estimates from column 3 of table 2, a one standard deviation decrease in median age (equal to 3.5 years in 2010) results in a 2.5 percentage point increase in the entrepreneurship rate, which is over 40 percent of the mean entrepreneurship rate across countries (equal to 0.061 in 2010).
Observation of multigap and coherence peak in the noncentrosymmetric superconductor CaPtAs: $^{75}$As nuclear quadrupole resonance measurement
Creators: name: Nagase, Yuya
name: Manago, Masahiro
name: Hayashi, Junichi
name: Takeda, Keiki
name: Tou, Hideki
name: Matsuoka, Eiichi
name: Sugawara, Hitoshi
name: Harima, Hisatomo
name: Kotegawa, Hisashi
Publisher: name: arXiv
Year: 2023
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: We present synthesis and $^{75}$As-nuclear quadrupole resonance (NQR) measurements for the noncentrosymmetric superconductor CaPtAs with a superconducting transition temperature $T_c$ of $\sim 1.5$ K. We discovered two different forms of CaPtAs during synthesis; one is a high-temperature tetragonal form that was previously reported, and the other is a low-temperature form consistent with the orthorhombic structure of CaPtP. According to the $^{75}$As-NQR measurement for superconducting tetragonal CaPtAs, the nuclear spin-lattice relaxation rate $1/T_1$ has an obvious coherence peak below $T_c$ and does not follow a simple exponential variation at low temperatures. These findings indicate that CaPtAs is a multigap superconductor and a large $s$-wave component.
description: 6 pages, 4 figures
From Gate to Gate: A Study of the Restorative Power of Marriage in Shakespeare's Measure for Measure
Creators: name: Elliott-Newton, Dyese
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2016

description: In early modern England, marriage was a problem, a big problem. Women might find themselves, nine months post vows, delivered of children to fathers who no longer acknowledged themselves husbands, to fathers no longer bound by either legal or religious obligations to the mothers of their offspring. The reasons for these ruptured marriages were many and varied, and the fallout that came in the wake of their disharmony, considerable. For England wasn’t simply dealing with a problem of broken households, of women and children with no means of support; instead ruptured marriage meant chaos across every aspect of English culture, from fallout in the criminal courts, as witnessed in the proliferation of bawdy houses and prostitution, to the spread of disease and increased mortality, to the wider problem of moral laxity and reprobation across the population.
Shakespeare’s Measure for Measure depicts how marital instabilities acted corrosively to corrupt and contaminate across the social order. I would argue that these failures emerged in part as a result of structural and doctrinal shifts within the English reformed church. When Martin Luther presented his reformed doctrine in the early years of the sixteenth century, he had hoped to free marriage from its sacramental standing, believing that the Catholic Church focused too much on ideas of forgiveness in sexual reproduction, seeking to promote celibacy as the holier occupation. Because England
had already split from the Catholic Church, ecclesiastical law on marriage was not re-established in 1563 when the Council of Trent settled the idea of marriage on the Continent. So too the English opted to leave that jurisdiction alone, refusing to re-organize marriage practices under civil authority until forced to do so during the Interregnum. Thus, the institution of marriage was grossly inadequate in England, inevitably causing the moral structure of the country to crumble. By the time Measure for Measure was written, there was a heritage of confusion concerning matrimony in England, and English society was rife with the kinds of corruptions that the play seems intent on exposing.
Towards Accurate Post-Training Quantization for Vision Transformer
Creators: name: Ding, Yifu
name: Qin, Haotong
name: Yan, Qinghua
name: Chai, Zhenhua
name: Liu, Junjie
name: Wei, Xiaolin
name: Liu, Xianglong
Publisher: name: arXiv
Year: 2023
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: FOS: Computer and information sciences

description: Vision transformer emerges as a potential architecture for vision tasks. However, the intense computation and non-negligible delay hinder its application in the real world. As a widespread model compression technique, existing post-training quantization methods still cause severe performance drops. We find the main reasons lie in (1) the existing calibration metric is inaccurate in measuring the quantization influence for extremely low-bit representation, and (2) the existing quantization paradigm is unfriendly to the power-law distribution of Softmax. Based on these observations, we propose a novel Accurate Post-training Quantization framework for Vision Transformer, namely APQ-ViT. We first present a unified Bottom-elimination Blockwise Calibration scheme to optimize the calibration metric to perceive the overall quantization disturbance in a blockwise manner and prioritize the crucial quantization errors that influence more on the final output. Then, we design a Matthew-effect Preserving Quantization for Softmax to maintain the power-law character and keep the function of the attention mechanism. Comprehensive experiments on large-scale classification and detection datasets demonstrate that our APQ-ViT surpasses the existing post-training quantization methods by convincing margins, especially in lower bit-width settings (e.g., averagely up to 5.17% improvement for classification and 24.43% for detection on W4A4). We also highlight that APQ-ViT enjoys versatility and works well on diverse transformer variants.
description: 9 pages, 5 figures, accepted by ACM Multimedia 2022
Engineering the Size of DNA Repair Inhibitor-Encapsulated Polymeric Nanoparticles to Improve the Therapeutic Index of Chemoradiotherapy
Creators: name: Yu, Stephanie
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2017

description: Nanoparticle (NP) delivery of chemotherapeutic drugs can be used to both improve tumor toxicity and reduce toxicity to normal tissue in chemo and chemoradiotherapy (CRT). However, various properties of nanoparticles with respect to CRT are yet to be explored. For instance, it is unknown how particle size may affect the therapeutic index of CRT. Exploration of this topic may provide invaluable insight on how NP-based CRT could be administered clinically in the future, as there is currently no set standard on an optimal particle size. PEG-PLGA nanoparticles were engineered encapsulating either the DNA-PK inhibitor Wortmannin (wtmn) or the ATM inhibitor KU60019 of various sizes (50, 100, or 150 nm in diameter) and studied their biodistribution, efficacy, and toxicity in CRT. Effects in vitro were observed in three colorectal adenocarcinoma lines (HT-29, SW480, and LoVo) and in vivo in mice. These nanoformulations were shown to be both cytotoxic and radiosensitizing in these cell lines, and there was no effect of particle size on toxicity in vitro. The largest particles were most rapidly cleared by the liver, but still penetrated tumors well in vivo. All sizes of nanoformulations were effective radiosensitizers of rectal tumor xenografts in vivo. In no instance did the largest or smallest particles appear to demonstrate any greater efficacy than medium sized particles when combined with radiation. The 50 nm KU60019 particles caused greater bowel toxicity than larger particles, and the 100 nm Wortmannin particles induced significantly more radiosensitization than larger or smaller particles in SW480 xenografts, a trend that was also observed in most other tumor/drug combinations. Radiation-induced rectal toxicity was minimal in animals treated with all three particle sizes. There was also no significant effect of particle size on hematologic of hepatotoxicity. These results demonstrate that particles in the 100 nm size range may be optimal for clinical applications in chemoradiotherapy.
Вопросы устойчивого развития общества,Выпуск 4 МКВГ 2023
Creators: name: ООО "Институт развития образования и консалтинга"
Publisher: name: ООО "Институт развития образования и консалтинга"
Year: 2023

description: Вопросы устойчивого развития общества,Выпуск 4 МКВГ 2023
Thought Leader or Mediator?: Exploring Different Leadership Approaches to Addressing Controversial Issues on Social Media
Creators: name: Harris, Anastazja
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2016

description: News of controversial events spread quickly through technology and social media. In August
2014, the fatal shooting of Michael Brown, an unarmed black teenager, by a white police officer
sparked national controversy. Facebook and Twitter users shared most of the event’s updates and
critiques. Social media users, especially those with a large following, faced the choice to either
speak up and express their opinions, or stay silent. The current study utilizes individual
interviews and a focus group to explore college student leaders’ use of social media in response
to the Michael Brown controversy. This study focuses on student leaders because they are more
likely to be cognizant of the impact of their online postings. In addition, leaders often face social
expectations to say something about hot topic issues. Interviews and the focus group revealed the
intersectionality of student leaders’ identities, although their online profiles may speak to one
more than another. Participants’ usage of social media varied depending on whether their online
identity focused more on their race, leadership position, or other personality traits. Overall,
findings demonstrate that student leaders’ identities impact their use of social media when
addressing controversial issues.
Chiral symmetries and Majorana fermions in coupled magnetic atomic chains on a superconductor
Creators: name: Xiao, Jinpeng
name: An, Jin
Publisher: name: arXiv
Year: 2015
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: We study the magnetic structures and their connections with topological superconductivity due to proximity effect for coupled magnetic atomic chains deposited on a superconductor. Several magnetic phases are self-consistently determined, including both the coplanar and non-coplanar ones. For a $N$-chain triangular atomic ladder, topologically nontrivial superconducting states can always be realized, but strongly depend on its magnetic structure and the number of atomic chains. When $N$ is even, the topologically nontrivial states with noncoplanar structures are characterized by $\mathbb{Z}_{2}$ invariants, while the topologically nontrivial noncoplanar states with an odd $N$ are characterized by integer $\mathbb{Z}$ invariants, due to the presence of a new chiral symmetry. The new chiral symmetry for the noncoplanar states is found to be robust against the on-site disorder, as long as the crystal reflection symmetry is respected.
description: 13 pages, 12 figures and 2 tables
SU(4) symmetry breaking revealed by magneto-optical spectroscopy in epitaxial graphene
Creators: name: Tan, Liang Z.
name: Orlita, Milan
name: Potemski, Marek
name: Palmer, James
name: Berger, Claire
name: de Heer, Walter A.
name: Louie, Steven G.
name: Martinez, Gérard
Publisher: name: arXiv
Year: 2015
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Refined infrared magnetotransmission experiments have been performed in magnetic fields B up to 35 T on a series of multilayer epitaxial graphene samples. Following the main optical transition involving the n=0 Landau level (LL), we observe a new absorption transition increasing in intensity with magnetic fields B>26 T. Our analysis shows that this is a signature of the breaking of the SU(4) symmetry of the n=0 LL. Using a quantitative model, we show that the only symmetry-breaking scheme consistent with our experiments is a charge density wave (CDW).
To Greek or Not To Greek? Impacts of Fraternity and Sorority Involvement on Academic Outcomes
Creators: name: Darvin, Andrew Joseph
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2013

description: The academic and social impacts of fraternal organizations on college campuses have
become a topic of more fervent debate in recent years. Recruitment websites for Greek life often
claim that fraternity and sorority members achieve greater levels of campus involvement and
academic success. Contrastingly, critics of the Greek system point to reputed negative social
impacts, including contributions to rape culture, dangerous hazing of new initiates, and
incidences of alcohol poisoning, and common media stereotypes to refute these claims. Using
data from the National Longitudinal Survey of Freshmen (NLSF), this paper investigates the
effect of participating in a Greek organization on academic outcomes such as grade point average
(GPA) and graduation rates for students at fairly selective postsecondary institutions. Employing
propensity score matching (PSM) with a nearest neighbor caliper method allowed for the
resampling of survey data to account for self-selection bias into fraternities and sororities.
Following PSM, ordinary least squares and probit regressions were used to determine the effect
of participation in Greek organization on GPA and graduation rates. A negative relationship was
found between Greek membership and cumulative GPA of roughly half of one letter mark (0.15
GPA points on a 4.0 scale), though participation in the Greek system is correlated with an
increased chance of graduating within four years and within six years.
An AI-driven intelligent traffic management model for 6G cloud radio access networks
Creators: name: Swain, Smruti Rekha
name: Saxena, Deepika
name: Kumar, Jatinder
name: Singh, Ashutosh Kumar
name: Lee, Chung-Nan
Publisher: name: arXiv
Year: 2023
Subjects: subject: Distributed, Parallel, and Cluster Computing (cs.DC)
subject: FOS: Computer and information sciences

description: This letter proposes a novel Cloud Radio Access Network (C-RAN) traffic analysis and management model that estimates probable RAN traffic congestion and mitigate its effect by adopting a suitable handling mechanism. A computation approach is introduced to classify heterogeneous RAN traffic into distinct traffic states based on bandwidth consumption and execution time of various job requests. Further, a cloud-based traffic management is employed to schedule and allocate resources among user job requests according to the associated traffic states to minimize latency and maximize bandwidth utilization. The experimental evaluation and comparison of the proposed model with state-of-the-art methods reveal that it is effective in minimizing the worse effect of traffic congestion and improves bandwidth utilization and reduces job execution latency up to 17.07% and 18%, respectively.
A lower bound on the number of cosmic ray events required to measure source catalogue correlations
Creators: name: Dolci, Marco
name: Romero-Wolf, Andrew
name: Wissel, Stephanie
Publisher: name: arXiv
Year: 2015
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: Recent analyses of cosmic ray arrival directions have resulted in evidence for a positive correlation with active galactic nuclei positions that has weak significance against an isotropic source distribution. In this paper, we explore the sample size needed to measure a highly statistically significant correlation to a parent source catalogue. We compare several scenarios for the directional scattering of ultra-high energy cosmic rays given our current knowledge of the galactic and intergalactic magnetic fields. We find significant correlations are possible for a sample of $>$1000 cosmic ray protons with energies above 60 EeV.
description: 23 pages, 9 figures
Early Childhood Abuse and Inhibition
Creators: name: Davis, Hannah
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2016

description: Child maltreatment is a prevalent issue among adolescent females. Threatening experiences are predictors for atypical neurobiological development which leads to maladaptive cognition and behavior during adolescent time periods. A subset of cognition is inhibition which encompasses both motor and reward inhibition. Childhood abuse alters reward sensitivity and processing allowing us to predict a decrease in the ability to inhibit rewarded responses compared to motor responses. A MID and CARIT task were used to measure both reward and motor inhibition. Self-reported child maltreatment and violence measures were then used to predict reward versus motor inhibition which were quantified as accuracy measures resulting from the CARIT task. Community violence marginally predicted a decrease in effective reward inhibition compared to motor inhibition. Reported maltreatment did not predict effective motor inhibition. This allows us to see the effect of abuse specifically on reward inhibition while also controlling for other outcomes of abuse such as psychopathology. Understanding the predictors of maladaptive behavior is useful in order to modify risky adolescent behavior appropriately. Future research should look at onset and frequency of maltreatment and the differing effects of specific forms of adversity.
Randomized-Controlled Evaluation of the Enhanced Assess, Acknowledge, and Act Sexual Assault Resistance Program
Creators: name: Lopez, Elise
name: Baiocchi, Michael
name: Koss, Mary
name: Swartout, Kevin
Publisher: name: Open Science Framework
Year: 2022

description: This project is a randomized controlled trial of EAAA, a sexual assault resistance program for first year college women. The trial will be conducted at five U.S. universities.
High velocity stars from the interaction of a globular cluster and a massive black hole binary
Creators: name: Fragione, Giacomo
name: Capuzzo-Dolcetta, Roberto
Publisher: name: arXiv
Year: 2015
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: High velocity stars are stars moving at velocities so high to require an acceleration mechanism involving binary systems or the presence of a massive central black hole. In the frame of a galaxy hosting a supermassive black hole binary (of total mass $10^8$ M$_\odot$), we investigated a mechanism for the production of high velocity stars due to the close interaction between a massive and orbitally decayed globular cluster and the super massive black hole binary. Some stars of the cluster acquire high velocities by conversion of gravitational energy into kinetic energy deriving from their interaction with the black hole binary. After the interaction, few stars reach a velocity sufficient to overcome the galactic gravitational well, while some of them are just stripped from the globular cluster and start orbiting around the galactic centre.
description: 8 pages, 4 figures. arXiv admin note: text overlap with arXiv:1509.03170
Highly polyploid HeLa cells depend on RCC1 to maintain effective chromatin condensation
Creators: name: Saunders, Hayden
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2016

description: Polyploidy, a common characteristic of cancer cell lines, puts extra pressure on the regulatory components of mitosis. Specifically, the process of chromatin condensation becomes especially critical due to the challenge of accurately aligning and segregating a multifold increase of DNA on the mitotic spindle. The regulator of chromosome condensation 1 (RCC1) is a protein bound to DNA throughout the cell cycle, which we have shown to be necessary for chromosome size scaling in C. elegans. We hypothesize that RCC1 levels increase in polyploid cells to compensate for this excess DNA content and promote adequate DNA condensation. We isolated populations of highly polyploid HeLa human cancer cells and found that RCC1 levels scale with DNA content in both highly polyploid and control HeLa cells. We believe that this scaling relationship is what affords highly polyploid cells the ability to maintain effective chromatin condensation and perhaps mitotic progression. Highly polyploid HeLa cells that have been stably transfected with a non-DNA-binding RCC1 mutant maintain their polyploidy through more rounds of division than do control polyploid populations. Analysis of metaphase chromosomes has revealed that these cells contain over-condensed chromosomes. We now believe that the loss of RCC1’s DNA-binding ability, which allows over-condensation of chromosomes, is what allows these highly polyploid cells to maintain effective rounds of mitosis, as smaller chromosomes are likely more easily segregated in highly polyploid cells.
Disability Rights as Social Movement in Argentina
Creators: name: Zakin, Zoe
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2016

description: In this paper I will investigate disability rights in Argentina—their history, current status, and future goals.  My primary research question is given that Argentina has great potential for a strong social movement to achieve disability rights, why has one not yet developed?  In order to continue with the proposition that there is no “strong social movement,” first we must ask: what is a social movement in this context? And what is the status of disability rights and activism in Argentina today, if they do not form one?  A subsequent sub-question asks what are the barriers to a full-fledged social movement forming?  Finally, I’ll question whether a social movement, in the ways its been described by Western social movement theory, would even be the most effective model to achieve the desired disability rights in Argentina.  To answer this, we must also ask what disability rights still need to be fulfilled, and what do activists most desire from their actions?  I will continue this introduction by sharing how I came to my questions and my methodology for answering them.
An Empirical Comparison of Three Psychometric Measures of Adolescent Substance Use
Creators: name: Brinberg, Miriam
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2015

description: Adolescent substance use is common and often accompanied by many negative consequences.
The psychometric assessment of substance use, however, is highly varied and may misrepresent
actual substance use. Given the importance of understanding adolescent substance use, this study
examined three competing measurement models of substance use and their differential
predictability of academic achievement and internalizing and externalizing symptomatology.
Participants were drawn from the public-use Add Health data set (N = 5,857). The three
measurement models were determined from seven items that assessed the lifetime use of
cigarettes, chewing tobacco, alcohol, marijuana, cocaine, inhalants, and other illicit drugs. The
first measurement model (lifetime use) grouped participants as abstainers (never used a drug)
and users (used at least one drug). The second measurement model (proportion) refined
substance users by accounting for the proportion of the seven drugs they endorsed. The final
measurement model further refined substance users by creating factor scores through
confirmatory factor analysis that allow each item to be differentially weighted as a function of
severity. Nine separate regression analyses were estimated in which age, race, gender, and
substance use measurement model predicted either academic achievement or externalizing or
internalizing symptomatology. These analyses indicated that all three substance use measures
were significant predictors of each outcome measure, but the proportion and factor score models
accounted for substantially more of the variance within each model. These results suggest the
proportion or factor score models would be better predictors of substance use, although the
choice of model should be based on relevant theory.
Persistent Near-Surface Flow Structures from Local Helioseismology
Creators: name: Howe, R.
name: Komm, R. W.
name: Baker, D.
name: Harra, L.
name: van Driel-Gesztelyi, L.
name: Bogart, R. S.
Publisher: name: arXiv
Year: 2015
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Near-surface flows measured by the ring-diagram technique of local helioseismology show structures that persist over multiple rotations. We examine these phenomena using data from the {\em Global Oscillation Network Group} (GONG) and the {\em Helioseismic and Magnetic Imager} (HMI) and show that a correlation analysis of the structures can be used to estimate the rotation rate as a function of latitude, giving a result consistent with the near-surface rate from global helioseismology and slightly slower than that obtained from a similar analysis of the surface magnetic field strength. At latitudes of 60$^{\circ}$ and above the HMI flow data reveal a strong signature of a two-sided zonal flow structure. This signature may be related to recent reports of "giant cells" in solar convection.
Trees on hyperbolic honeycombs
Creators: name: Németh, László
Publisher: name: arXiv
Year: 2015
Subjects: subject: Combinatorics (math.CO)
subject: FOS: Mathematics
subject: 05C05, 52C20

description: In the hyperbolic plane there are infinite regular lattices. From a fix vertex of a lattice tree graphs can be constructed recursively to the next layers with edges of the lattice. In this article we examine the properties of the growing of trees and the probabilities of length of trees considering the vertices on level i.
description: 8 pages, 6 figures, http://mat76.mat.uni-miskolc.hu/~mnotes/index.php?page=article&name=mmn_783
Hyperplane mass partitions via relative equivariant obstruction theory
Creators: name: Blagojević, Pavle V. M.
name: Frick, Florian
name: Haase, Albert
name: Ziegler, Günter M.
Publisher: name: arXiv
Year: 2015
Subjects: subject: Algebraic Topology (math.AT)
subject: Combinatorics (math.CO)
subject: Metric Geometry (math.MG)
subject: FOS: Mathematics
subject: 55N25, 51N20, 52A35, 55R20

description: The Grünbaum-Hadwiger-Ramos hyperplane mass partition problem was introduced by Grünbaum (1960) in a special case and in general form by Ramos (1996). It asks for the "admissible" triples $(d,j,k)$ such that for any $j$ masses in $\mathbb{R}^d$ there are $k$ hyperplanes that cut each of the masses into $2^k$ equal parts. Ramos' conjecture is that the Avis-Ramos necessary lower bound condition $dk\ge j(2^k-1)$ is also sufficient. We develop a "join scheme" for this problem, such that non-existence of an $G_k$-equivariant map between spheres $(S^d)^{*k} \rightarrow S(W_k\oplus U_k^{\oplus j})$ that extends a test map on the subspace of $(S^d)^{*k}$ where the hyperoctahedral group $G_k$ acts non-freely, implies that $(d,j,k)$ is admissible. For the sphere $(S^d)^{*k}$ we obtain a very efficient regular cell decomposition, whose cells get a combinatorial interpretation with respect to measures on a modified moment curve. This allows us to apply relative equivariant obstruction theory successfully, even in the case when the difference of dimensions of the spheres $(S^d)^{*k}$ and $S(W_k\oplus U_k^{\oplus j})$ is greater than one. The evaluation of obstruction classes leads to counting problems for concatenated Gray codes. Thus we give a rigorous, unified treatment of the previously announced cases of the Grünbaum-Hadwiger-Ramos problem, as well as a number of new cases for Ramos' conjecture.
description: 29 pages, 2 figures