cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
FU Orionis disk outburst: evidence for a gravitational instability scenario triggered in a magnetically dead zone
Creators: name: Bourdarot, G.
name: Berger, J-P.
name: Lesur, G.
name: Perraut, K.
name: Malbet, F.
name: Millan-Gabet, R.
name: Bouquin, J-B. Le
name: Garcia-Lopez, R.
name: Monnier, J. D.
name: Labdon, A.
name: Kraus, S.
name: Labadie, L.
name: Aarnio, A.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: Context: FUors outbursts are a crucial stage of accretion in young stars. However a complete mechanism at the origin of the outburst still remains missing. Aims: We aim at constraining the instability mechanism in FU Orionis star itself, by directly probing the size and the evolution in time of the outburst region with near-infrared interferometry, and to confront it to physical models of this region. Methods: FU Orionis has been a regular target of near-infrared interferometry. In this paper, we analyze more than 20 years of interferometric observations to perform a temporal monitoring of the region of the outburst, and compare it to the spatial structure deduced from 1D MHD simulations. Results: We measure from the interferometric observations that the size variation of the outburst region is compatible with a constant or slightly decreasing size over time in the H and K band. The temporal variation and the mean sizes are consistently reproduced by our 1D MHD simulations. We find that the most compatible scenario is a model of an outburst occurring in a magnetically layered disk, where a Magneto-Rotational Instability (MRI) is triggered by a Gravitational Instability (GI) at the outer edge of a dead-zone. The scenario of a pure Thermal Instability (TI) fails to reproduce our interferometric sizes since it can only be sustained in a very compact zone of the disk <0.1 AU. The scenario of MRI-GI could be compatible with an external perturbation enhancing the GI, such as tidal interactions with a stellar companion, or a planet at the outer edge of the dead-zone. Conclusions: The layered disk model driven by MRI turbulence is favored to interpret the spatial structure and temporal evolution of FU Orionis outburst region. Understanding this phase gives a crucial link between the early phase of disk evolution and the process of planet formation in the first inner AUs.
description: Accepted for publication in A&A
Empathy and emotion regulation in inpatients of forensic psychiatry
Creators: name: Burghart, Matthias
name: Mier, Daniela
name: Bulla, Jan
Publisher: name: Open Science Framework
Year: 2022
Subjects: subject: Clinical Psychology
subject: Social and Behavioral Sciences
subject: Psychology
subject: FOS: Psychology
subject: emotion regulation
subject: empathy
subject: forensic
subject: psychiatry
subject: psychopathy

description: In this project, we investigate levels of expressed empathy and emotion regulation capacities among inpatients of a forensic psychiatry in Germany. Matched healthy controls from the general population are recruited and compared to forensic inpatients on a variety of psychological measures, including both, questionnaires and experimental paradigms. In addition, potential associations between empathy/emotion dysregulation and psychopathy, impulsivity, and alexithymia are examined. Our project comprises two parts: (1) a cross-sectional comparison (= this project); and (2) a longitudinal study that aims to determine whether treatment has a positive impact on inpatients’ level of empathy and use of adaptive emotion regulation strategies (= separate project on OSF). The findings will add to our understanding of empathy and emotion dysregulation among forensic inpatients and help to improve treatment in forensic facilities.
Open Science in Archaeobotany - The FAIR Phytoliths Project
Creators: name: Kerfant, Celine
name: Karoune, Emma
name: Lancelotti, Carla
name: Ruiz-Pérez, Javier
name: García-Granero, Juan José
name: Madella, Marco
Publisher: name: Zenodo
Year: 2022
Subjects: Open data
FAIR data
Archaeobotany
Phytoliths

description: This presentation was given at the 2nd Virtual Conference for Women Archaeologists and Palaeontologists on 7th March 2022. It introduces open science, the work of the FAIR Phytolith Project, what the FAIR principles are and how open and FAIR data can benefit researchers. It then goes on to discuss some of the early findings of the FAIR assessment of existing phytolith data such as a need for changing our data sharing practices and increasing the transparency of methods. At the end of the talk, suggestions are made about how to improve these practices for phytolith researchers and more widely archaeobotanists.
Strong Suppression of the Spin Hall Effect in the Spin Glass State
Creators: name: Niimi, Y.
name: Kimata, M.
name: Omori, Y.
name: Gu, B.
name: Ziman, T.
name: Maekawa, S.
name: Fert, A.
name: Otani, Y.
Publisher: name: arXiv
Year: 2015
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: We have measured spin Hall effects in spin glass metals, CuMnBi alloys, with the spin absorption method in the lateral spin valve structure. Far above the spin glass temperature Tg where the magnetic moments of Mn impurities are randomly frozen, the spin Hall angle of CuMnBi ternary alloy is as large as that of CuBi binary alloy. Surprisingly, however, it starts to decrease at about 4Tg and becomes as little as 7 times smaller at 0.5Tg. A similar tendency was also observed in anomalous Hall effects in the ternary alloys. We propose an explanation in terms of a simple model considering the relative dynamics between the localized moment and the conduction electron spin.
description: 5 pages, 4 figures
The comparison of effectiveness between hand hygiene and face masks to the reduced risk of respiratory infections
Creators: name: Jiesisibieke, Zhu
Publisher: name: Open Science Framework
Year: 2022
Subjects: subject: Immunology and Infectious Disease
subject: Medicine and Health Sciences
subject: Life Sciences

description: Purpose. This meta-analysis is conducted to assess whether hand hygiene and face masks could reduce the risk of respiratory infections respectively and whether hand hygiene plus face masks could reduce the risk of respiratory infections. Methods. We searched The Cochrane Library, PubMed, and EMBASE for relevant studies without language limitations before 15 July 2020 with a priori defined inclusion and exclusion criteria. Ten randomized studies and three observational studies were included for systematic review and meta-analysis.
Structural and Optoelectronic Properties of Thin Film LaWN$_3$
Creators: name: Smaha, Rebecca W.
name: Mangum, John S.
name: Leahy, Ian A.
name: Calder, Julian
name: Hautzinger, Matthew P.
name: Muzzillo, Christopher P.
name: Perkins, Craig L.
name: Talley, Kevin R.
name: Eley, Serena
name: Gorai, Prashun
name: Bauers, Sage R.
name: Zakutayev, Andriy
Publisher: name: arXiv
Year: 2023
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Nitride perovskites are an emerging class of materials that have been predicted to display a range of interesting physics and functional properties, but they are under-explored due to the difficulty of synthesizing oxygen-free nitrides. LaWN3, recently reported as the first oxygen-free nitride perovskite, exhibited polar symmetry and a large piezoelectric coefficient. However, the predicted ferroelectric switching was hindered by large leakage current, which motivates better understanding of its electronic structure and optical properties. Here, we study the structure and optoelectronic properties of thin film LaWN3 in greater detail, employing combinatorial techniques to correlate these properties with cation stoichiometry. We report a two-step synthesis that utilizes a more common RF substrate bias instead of a nitrogen plasma source, yielding nanocrystalline films that are crystallized by ex-situ annealing. We investigate the structure and composition of these films, finding polycrystalline La-rich and highly textured W-rich films. The optical absorption onset and temperature- and magnetic field-dependent resistivity are consistent with semiconducting behavior and are highly sensitive to cation stoichiometry, which may be related to amorphous impurities: metallic W or WNx in W-rich samples and insulating La2O3 in La-rich samples. The fractional magnetoresistance is linear and small, consistent with defect scattering, and a W-rich sample has n-type carriers with high densities and low mobilities. We demonstrate a photoresponse in LaWN3: the resistivity of a La-rich sample is enhanced by 28% at low temperature, likely due to a defect trapping mechanism. The physical properties of LaWN3 are highly sensitive to cation stoichiometry, like many oxide perovskites, which therefore calls for precise composition control to utilize the interesting properties observed in this nitride perovskite.
QUANTITATIVE ANALYSIS OF DISTRIBUTED LEADERSHIP IN SCHOOLS USING STATEWIDE TEACHER PERCEPTION SURVEYS
Creators: name: Ware, Lewis Andrew
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2019

description: ABSTRACT      Drew Ware: Quantitative Analysis of Distributed Leadership in Schools Using Statewide Teacher Perception Surveys      (Under the direction of Erick Houck)      Leadership that is intentionally and thoughtfully distributed across many in a school building has the potential to bring about positive change for all students and to empower and engage teachers in such a way that makes them more likely to stay in the classroom.  Given the potential of distributed leadership, understanding it more deeply is critical for schools to see the potential benefits.   This study has sought to accomplish that goal by first creating two measures of distributed leadership that can be applied to a wide range of schools using a state-wide teacher perception survey.   One measure  (DL 1) was created using a literature review on distributed leadership to identify questions from the North Carolina Teacher Working Conditions Survey that illustrate this concept.  The other measure (DL 2)  used confirmatory factor analysis to identify questions from this same survey that were indicators of the underlying factor of distributed leadership.  Then this paper compared these two measures of distributed leadership with specific school characteristics, focusing on teacher turnover rates at the school level.   After controlling for the school characteristics of poverty, academic achievement, academic growth, school level and the district for a school, a small but statistically significant correlation between the distributed leadership measures and teacher turnover rates still remained.   Thus distributed leadership, as understood using the measures identified from the North Carolina Teacher Working Conditions Survey, correlates with teacher turnover rates.   Now with the first measure of distributed leadership (DL1), school and district administrators can use it to target schools for growth in this area, set goals for schools and for school principals, and monitor implementation of a distributed model.  With the second measure (DL2), researchers can better understand distributed leadership and its impact on students, staff, and schools.   Distributed leadership has the potential to lead us forward towards better schools for learning and better schools in which to work.  This paper helps us move closer to realizing how.
Massive pre-main-sequence stars in M17: $1^{\rm st}$ and $2^{\rm nd}$ overtone CO bandhead emission and the thermal infrared
Creators: name: Poorta, J.
name: Ramírez-Tannus, M. C.
name: de Koter, A.
name: Backs, F.
name: Derkink, A.
name: Bik, A.
name: Kaper, L.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: Recently much progress has been made in probing the embedded stages of massive star formation, pointing to formation scenarios akin to a scaled up version of low-mass star formation. However, the latest stages of massive star formation have rarely been observed. Using 1st and 2nd overtone CO bandhead emission and near- to mid-infrared photometry we aim to characterize the remnant formation disks around 5 unique pre-main-sequence (PMS) stars with masses $6-12~\rm M_{\odot}$, that have constrained stellar parameters thanks to their detectable photospheres. We seek to understand this emission and the disks it originates from in the context of the evolutionary stage of the studied sources. We use an analytic LTE disk model to fit the CO bandhead and the dust emission, found to originate in different disk regions. For the first time we modeled the 2nd overtone emission. Furthermore, we fit continuum normalized bandheads and show the importance of this in constraining the emission region. We also include $^{13}\rm CO$ in our models as an additional probe of the young nature of the studied objects. We find that the CO emission originates in a narrow region close to the star (<1 AU) and under very similar disk conditions (temperatures and densities) for the different objects. This is consistent with previous modeling of this emission in a diverse range of young stellar objects. We discuss these results in the context of the positions of these PMS stars in the Hertzsprung-Russel diagram and the CO emission's association with early age and high accretion rates in (massive) young stellar objects. We conclude that, considering their mass range and for the fact that their photospheres are detected, the M17 PMS stars are observed in a relatively early formation stage. They are therefore excellent candidates for longer wavelength studies to further constrain the end stages of massive star formation.
description: 21 pages, 12 figures
"Enemies not Amenable:" Violence, Journalism, and the Russian State Building Project
Creators: name: Anderson, Liam John
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2019

description: Western coverage of Russian journalism often bemoans the current state of Russian independent media: shrinking every year, with an increasing number of websites, journals, and newspapers either forced to close following legal action or purchased by state-affiliated media companies. When Russian journalists appear in Western publications, it is often because of their murder or beating and the intense scrutiny that it receives from outside of Russia. While Russia is understood to be enormously dangerous for independent, critical journalists to operate in according to several journalism watchdogs, Russian independent media carries on, and remains a significant force in Russian civil society. Given the continued existence of independent Russian journalism, and its willingness to investigate the Russian state, why do certain members of the Russian media become targets of violence? This paper, through a case study approach, contends that, while no absolute cause can be identified all the time, journalists who attack the Russian state building project since Vladimir V Putin’s election to the Presidency in 2000 are at a greater risk of being attacked with their attackers receiving impunity for their actions.
A Thru-free Multiline Calibration
Creators: name: Hatab, Ziad
name: Gadringer, Michael Ernst
name: Bösch, Wolfgang
Publisher: name: arXiv
Year: 2023
Subjects: subject: Applied Physics (physics.app-ph)
subject: Signal Processing (eess.SP)
subject: FOS: Physical sciences
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: This paper proposes a modification to the traditional multiline thru-reflect-line (TRL) or line-reflect-line (LRL) calibration method used for vector network analyzers (VNAs). Our proposed method eliminates the need for a thru (or line) standard by using an arbitrary transmissive two-port device in combination with an additional reflect standard. This combination of standards allows us to arbitrarily set the location of the calibration plane using physical artifacts. In contrast to the standard multiline TRL method, the suggested approach avoids a post-processing step to shift the calibration plane if a line standard is used. We demonstrate our proposed method with measurements on a printed circuit board (PCB) and compare it to the multiline TRL method with a perfectly defined thru.
description: GitHub: https://github.com/ZiadHatab/thru-free-multiline-calibration
On birational boundedness of Fano fibrations
Creators: name: Jiang, Chen
Publisher: name: arXiv
Year: 2015
Subjects: subject: Algebraic Geometry (math.AG)
subject: FOS: Mathematics

description: We investigate birational boundedness of Fano varieties and Fano fibrations. We establish an inductive step towards birational boundedness of Fano fibrations via conjectures related to boundedness of Fano varieties and Fano fibrations. As corollaries, we provide approaches towards birational boundedness and boundedness of anti-canonical volumes of varieties of $ε$-Fano type. Furthermore, we show birational boundedness of $3$-folds of $ε$-Fano type.
description: 21 pages. Comments are welcome; v2: final version, terminology changed, to appear in Amer. J. Math
Video Capsule Endoscopy Review of Commercial Technologies
Creators: name: Pandey, Santosh
Publisher: name: figshare
Year: 2023
Subjects: Diagnostic radiography
Endocrinology
Clinical microbiology
Gastroenterology and hepatology
Infectious diseases
Food engineering
Chemical engineering design
Separation technologies
Process control and simulation
Biologically active molecules
Molecular medicine
Characterisation of biological macromolecules
Biomolecular modelling and design

description: The structure and functions of the mammalian gastrointestinal tract are dependent on the body and size of the organism, nature and frequency of food intake, need for food storage, and adaptation needs. We introduce the structure and functions of the gastrointestinal tract, and the FDA guidelines for ingestible wireless telemetric medical devices. We survey the advanced features incorporated in ingestible capsule systems, such as microrobotics, closed-loop feedback, physiological sensing, nerve stimulation, sampling and delivery, panoramic imaging with adaptive frame rates, and rapid reading software. Examples of experimental and commercialized capsule systems are presented with descriptions of their sensors, devices, and circuits for gastrointestinal health monitoring. We also show the recent research in biocompatible materials and batteries, edible electronics, and alternative energy sources for ingestible capsule systems. The results from clinical studies are discussed for the assessment of key performance indicators related to the safety and effectiveness of ingestible capsule procedures. Lastly, the present challenges and outlook are summarized with respect to the risks to health, clinical testing and approval process, and technology adoption by patients and clinicians.
Dynamic stability of the Solar System: Statistically inconclusive results from ensemble integrations
Creators: name: Zeebe, Richard E.
Publisher: name: arXiv
Year: 2015
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: Due to the chaotic nature of the Solar System, the question of its long-term stability can only be answered in a statistical sense, for instance, based on numerical ensemble integrations of nearby orbits. Destabilization of the inner planets, leading to close encounters and/or collisions can be initiated through a large increase in Mercury's eccentricity, with a currently assumed likelihood of ~1%. However, little is known at present about the robustness of this number. Here I report ensemble integrations of the full equations of motion of the eight planets and Pluto over 5 Gyr, including contributions from general relativity. The results show that different numerical algorithms lead to statistically different results for the evolution of Mercury's eccentricity (eM). For instance, starting at present initial conditions (eM ~= 0.21), Mercury's maximum eccentricity achieved over 5 Gyr is on average significantly higher in symplectic ensemble integrations using heliocentricthan Jacobi coordinates and stricter error control. In contrast, starting at a possible future configuration (eM ~= 0.53), Mercury's maximum eccentricity achieved over the subsequent 500 Myr is on average significantly lower using heliocentric than Jacobi coordinates. For example, the probability for eM to increase beyond 0.53 over 500 Myr is >90% (Jacobi) vs. only 40-55% (heliocentric). This poses a dilemma as the physical evolution of the real system - and its probabilistic behavior - cannot depend on the coordinate system or numerical algorithm chosen to describe it. Some tests of the numerical algorithms suggest that symplectic integrators using heliocentric coordinates underestimate the odds for destabilization of Mercury's orbit at high initial eM.
Searching for dark jets with displaced vertices using weakly supervised machine learning
Creators: name: Bardhan, Debjyoti
name: Kats, Yevgeny
name: Wunch, Noam
Publisher: name: arXiv
Year: 2023
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: If "dark quarks" from a confining hidden sector are produced at the LHC, they will shower and hadronize to dark sector hadrons, which may decay back to Standard Model particles within the detector, possibly resulting in a collimated spray of particles resembling a QCD jet. In this work we address scenarios in which dark hadrons decay with a measurable small displacement, such that the relevant background is dominated by heavy-flavor jets. Since dark sector parameters are largely unconstrained, and the precise properties of a dark QCD-like theory are difficult to compute or simulate reliably in any case, model-independent, data-based searches for such scenarios are desirable. We explore a search strategy employing weakly supervised machine learning to search for anomalous jets with displaced vertices. The method is tested on several toy signals, demonstrating the feasibility of such a search. Our approach has potential to outperform simple cut-based methods in some cases and has the advantage of being more model-independent.
description: 30 pages, 14 figures; v2: minor improvements of presentation; published version
Affective rating of audio and video clips using the EmojiGrid
Creators: name: Toet, Alexander
Publisher: name: Open Science Framework
Year: 2022
Subjects: subject: Social and Behavioral Sciences
subject: affective appraisal
subject: affective rating
subject: arousal
subject: EmojiGrid
subject: emotions
subject: sounds
subject: valence
subject: video clips

description: The present study was performed to validate the EmojiGrid as a self-report tool for the affective appraisal of sounds and video.
Analysing the economy-wide impact of the supply chains activated by a new biomass power plant. The case of cardoon in Sardinia
Creators: name: Bonfiglio, Andrea
name: Esposti, Roberto
Publisher: name: Bio-based and Applied Economics
Year: 2015

description: This study investigates the impact on the economy of Sardinia (Italy) generated by a new biomass power plant fed by locally cultivated cardoon. The cardoon also serves the production of biopolymers. The impact is assessed at an economy-wide level using two multiregional closed Input-Output models, which allow us to take into account the entire supply chain activated and the supra-local effects generated by trade across local industries. The effects are computed under alternative scenarios simulating different levels of substitution of existing agricultural activities with the new activity (cardoon). Results show positive and locally significant impacts in terms of value added and employment. However, these impacts are substantially influenced by the degree of substitution. Results also suggest that there are specific territorial areas that are more sensitive to negative effects induced by substitution.
description: Bio-based and Applied Economics, Vol 5 No 1 (2016)
Segue: Overviewing Evolution Patterns of Egocentric Networks by Interactive Construction of Spatial Layouts
Creators: name: Law, Po-Ming
name: Wu, Yanhong
name: Basole, Rahul
Publisher: name: Open Science Framework
Year: 2022
Subjects: subject: dimensionality reduction
subject: dynamic network
subject: visualization

description: Getting the overall picture of how a large number of ego-networks evolve is a common yet challenging task. Existing techniques often require analysts to inspect the evolution patterns of ego-networks one after another. In this study, we explore an approach that allows analysts to interactively create spatial layouts in which each dot is a dynamic ego-network. These spatial layouts provide overviews of the evolution patterns of ego-networks, thereby revealing different global patterns such as trends, clusters and outliers in evolution patterns. To let analysts interactively construct interpretable spatial layouts, we propose a data transformation pipeline, with which analysts can adjust the spatial layouts and convert dynamic ego-networks into event sequences to aid interpretations of the spatial positions. Based on this transformation pipeline, we develop Segue, a visual analysis system that supports thorough exploration of the evolution patterns of ego-networks. Through two usage scenarios, we demonstrate how analysts can gain insights into the overall evo-lution patterns of a large collection of ego-networks by interactively creating different spatial layouts.
The Longitudinal Trajectories of Internalizing Symptoms in Individuals with 22q11.2 Deletion Syndrome
Creators: name: Patel, Tapan
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2019

description: Internalizing symptoms (i.e., anxiety, depression, withdrawal) are highly prevalent in the 22q11.2 Deletion Syndrome (22q11DS) population. There is a need to identify how these symptoms change over time and to determine what factors affect the trajectory of these symptoms. The purpose of this research is to determine how internalizing symptoms change over time and how factors such as intelligence, attention, working memory, and demographics affect these trajectories. Due to the nature of 22q11DS, the presence of these internalizing symptoms further debilitates these individuals. There is a need to identify how and when interventions can address these symptoms. Data was analyzed using multilevel modeling. Results showed that internalizing trajectories improved as time progressed, and demographics had a significant effect while cognitive symptoms of 22q11DS had no effect on these trajectories. The implications of these findings are discussed.
Interplay between effective mass anisotropy and Pauli paramagnetic effects in a multiband superconductor--Application to Sr2RuO4--
Creators: name: Nakai, Noriyuki
name: Machida, Kazushige
Publisher: name: arXiv
Year: 2015
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: We investigate the mixed state properties in a type II multiband superconductor with uniaxial anisotropy under the Pauli paramagnetic effects. Eilenberger theory extended to a multiband superconductor is utilized to describe the detailed vortex lattice properties, such as the flux line form factors, the vortex lattice anisotropy and magnetic torques. We apply this theory to Sr$_2$RuO$_4$ to analyze those physical quantities obtained experimentally, focusing on the interplay between the strong two-dimensional anisotropy and the Pauli paramagnetic effects. This study allows us to understand the origin of the disparity between the vortex lattice anisotropy ($\sim$60) and the $H_{\rm c2}$ anisotropy ($\sim$20). Among the three bands; $γ$ with the effective mass anisotropy $\sim$180, $α$ with $\sim$120, and $β$ with $\sim$60, the last one is found to be the major band, responsible for various magnetic responses while the minor $γ$ band plays an important role in the vortex formation. Namely, in a field orientation slightly tilted away from the two dimensional basal plane those two bands cooperatively form the optimal vortex anisotropy which exceeds that given by the effective mass formula with infinite anisotropy. This is observed by small angle neutron scattering experiments on Sr$_2$RuO$_4$. The pairing symmetry of Sr$_2$RuO$_4$ realized is either spin singlet or spin triplet with the d-vector strongly locked in the basal plane. The gap structure is that the major $β$ band has a full gap and the minor $γ$ band has a $d_{x^2-y^2}$ like gap.
description: 14 pages, 18 figures, to appear in Phys. Rev. B
Anomalous polarization dependence of Raman scattering and crystallographic orientation of black phosphorus
Creators: name: Kim, Jungcheol
name: Lee, Jae-Ung
name: Lee, Jinhwan
name: Park, Hyo Ju
name: Lee, Zonghoon
name: Lee, Changgu
name: Cheong, Hyeonsik
Publisher: name: arXiv
Year: 2015
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: We investigated polarization dependence of the Raman modes in black phosphorus (BP) using five different excitation wavelengths. The crystallographic orientation was determined by comparing polarized optical microscopy with high-resolution transmission electron microscope analysis. In polarized Raman spectroscopy, the B2g mode shows the same polarization dependence regardless of the excitation wavelength or the sample thickness. On the other hand, the Ag1 and Ag2 modes show a peculiar polarization behavior that depends on the excitation wavelength and the sample thickness. The thickness dependence can be explained by considering the anisotropic interference effect due to birefringence and dichroism of the BP crystal, but the wavelength dependence cannot be explained. We propose a simple and fail-proof procedure to determine the orientation of a BP crystal by combining polarized Raman scattering with polarized optical microscopy.
description: 22+7 pages, 8+5 figures
Implementation of sustainable forest management: an application of the triple perspective typology of stakeholder theory in a case study in Sabah, Malaysia
Creators: name: Lintangah, Walter
name: Weber, Norbert
Publisher: name: Journal of Forest and Landscape Research
Year: 2015

description: The progress of the concept of Sustainable Forest Management (SFM) is dynamic and its success or failure during implementation can be evaluated in different ways. In a detailed survey in four Forest Management Units (FMUs) in Sabah, the current implementation of SFM at the FMU level was assessed based on the triple perspective typology of stakeholder theory. This approach encompasses conceptual, corporate and stakeholder centric point of view. The conceptual perspective explores the SFM concept and how it relates to the FMU holder – stakeholder interaction at the FMU level, the corporate perspective examined how the FMU holders put the concept into practise and address their stakeholders, while the stakeholder perspective analyses how the stakeholders attempt to accomplish their claims and interests through the corporate-centric (FMU holders) at the management level. The stakeholder analysis provides the platform for stakeholder identification, categorisation and their general perception and behaviour towards the overall performance of SFM objectives. The Stakeholder Relation Management (SRM) that integrates the FMU holders and stakeholder participation under the SFM concept were also identified. Different FMU holders are engaged with distinct objectives to be achieved, which determine their direct relationship with the stakeholders. The stakeholders were attributed to static and dynamic groups, which are determined by their existence, claims and interests, and involvement in various SFM programs and activities at the FMU level. They provided distinguished preference and agreement toward various issues and characteristics related to SFM objectives, implementation and stakeholder participation at the management level. Most of the respondents of the multi-interest stakeholder group agreed with SFM main contributions towards the elements of environmental objectives, followed by economic objectives and elements of social objectives. The approach for SFM assessment based on the different lenses of conceptual, corporate and stakeholder centric provides complementary evidence on the pragmatic implementation of SFM at the forest management level.
description: Journal of Forest and Landscape Research, Vol 1 No 1 (2015)
A Search for Additional Neutral Higgs Bosons in $\tau\tau$ Final States in pp Collisions at $\sqrt{s} = 13\, \mathrm{TeV}$
Creators: name: Burkart, Maximilian
Publisher: name: Karlsruher Institut für Technologie (KIT)
Year: 2023
Subjects: CERN
LHC
CMS
Particle Physics
Higgs
Tau Leptons
BSM
MSSM
2HDM

description: Many proposed extensions of the standard model of particle physics (SM) predict an extended Higgs sector with respect to the SM. Experimentally, this extended Higgs sector is accessible through searches for additional spin-0 particles often referred to as additional Higgs bosons. Decays of neutral Higgs bosons to pairs of tau leptons provide the prime search channel for such particles in the minimal supersymmetric SM (MSSM) and other two-Higgs-doublet models (2HDM) of Type II since their couplings are enhanced in wide areas of the parameter space. In this thesis, a search for such decays in the form of a search for an additional resonance above the SM prediction in the $\tau\tau$ mass spectrum, targeting the production via gluon fusion and in association with b quarks, is presented. The results are portrayed in two ways. First, model-independent exclusion limits on the product of the production cross section and the branching fraction for the decay into tau leptons of the targeted resonance are derived. These limits translate into model-dependent exclusion contours in a set of MSSM and 2HDM benchmark scenarios, which are inferred from the full $\tau\tau$ spectrum predicted by the investigated scenario.
Examining Postsecondary Student Athletes' Cognitive Beliefs About Sport Setbacks
Creators: Pelletier, Gabrielle N.
Parker, Patti C.
Publisher: name: University of Alberta Library
Year: 2022

In the Fall of 2021, 200 competitive postsecondary student athletes (Canada & USA) responded to an online survey about their cognitive beliefs related to sport setbacks during COVID-19. Dr. Parker and the ACME team would like to thank all participants as well as SSHRC for funding this research. The following is a summary highlighting some of our findings.
Room temperature dielectric and magnetic properties of Gd and Ti co-doped BiFeO$_{3}$ ceramics
Creators: name: Basith, M. A.
name: Kurni, O.
name: Alam, M. S.
name: Sinha, B. L.
name: Ahmmad, Bashir
Publisher: name: arXiv
Year: 2015
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Room temperature dielectric and magnetic properties of BiFeO$_3$ samples, co-doped with magnetic Gd and non-magnetic Ti in place of Bi and Fe, respectively, were reported. The nominal compositions of Bi$_{0.9}$Gd$_{0.1}$Fe$_{1-x}$Ti$_x$O$_3$ (x = 0.00-0.25) ceramics were synthesized by conventional solid state reaction technique. X-ray diffraction patterns revealed that the substitution of Fe by Ti induces a phase transition from rhombohedral to orthorhombic at x $>$ 0.20. Morphological studies demonstrated that the average grain size was reduced from $\sim {~}$1.5 $μm$ to $\sim {~}$200 $nm$ with the increase in Ti content. Due to Ti substitution, the dielectric constant was stable over a wide range of high frequencies (30 kHz to 20 MHz) by suppressing the dispersion at low frequencies. The dielectric properties of the compounds are associated with their improved morphologies and reduced leakage current densities probably due to the lower concentration of oxygen vacancies in the compositions. Magnetic properties of Bi$_{0.9}$Gd$_{0.1}$Fe$_{1-x}$Ti$_x$O$_3$ (x = 0.00-0.25) ceramics measured at room temperature were enhanced with Ti substitution up to 20 $\%$ compared to that of pure BiFeO$_3$ and Ti undoped Bi$_{0.9}$Gd$_{0.1}$FeO$_3$ samples. The enhanced magnetic properties might be attributed to the substitution induced suppression of spiral spin structure of BiFeO$_3$. An asymmetric shifts both in the field and magnetization axes of magnetization versus magnetic field (M-H) curves was observed. This indicates the presence of exchange bias effect in these compounds notably at room temperature.
description: 8 pages, 5 figures
Low Contrast Dielectric Metasurface Optics
Creators: name: Zhan, Alan
name: Colburn, Shane
name: Trivedi, Rahul
name: Dodson, Chris
name: Majumdar, Arka
Publisher: name: arXiv
Year: 2015
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: The miniaturization of current image sensors is largely limited by the volume of the optical elements. Using a sub-wavelength patterned quasi-periodic structure, also known as a metasurface, one can build planar optical elements based on the principle of diffraction. However, it was believed that high refractive index materials are required for metasurface optics. Here, we show that one can employ the design principles of a metasurface even with low contrast materials, such as silicon nitride. We validate our theory by fabricating and experimentally characterizing several silicon nitride based lenses and vortex beam generators . The fabricated lenses achieved beam spots of less than 1 μm with numerical apertures as high as ~ 0.75. A transmission efficiency of 90% and focusing efficiency of 40% in the visible regime was observed. Our results pave the way towards building low-loss metasurface based optical elements at visible frequencies using low contrast materials.
description: 6 figures
Center of the universal Askey--Wilson algebra at roots of unity
Creators: name: Huang, Hau-Wen
Publisher: name: arXiv
Year: 2015
Subjects: subject: Quantum Algebra (math.QA)
subject: FOS: Mathematics
subject: 17B37, 20C08, 33C45, 33D80

description: Inspired by a profound observation on the Racah--Wigner coefficients of $U_q(\mathfrak{sl}_2)$, the Askey--Wilson algebras were introduced in the early 1990s. A universal analog $\triangle_q$ of the Askey--Wilson algebras was recently studied. For $q$ not a root of unity, it is known that $Z(\triangle_q)$ is isomorphic to the polynomial ring of four variables. A presentation for $Z(\triangle_q)$ at $q$ a root of unity is displayed in this paper. As an application, a presentation for the center of the double affine Hecke algebra of type $(C_1^\vee,C_1)$ at roots of unity is obtained.
An Exploration of Teacher Retention in Rural No Excuse Charter Schools in the United States
Creators: name: Olsen, Jackson Tanner
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2019

description: Teachers are the primary drivers of student outcomes and are crucial to the life and health of our education system. And yet, teacher attrition in American schools has steadily risen over the past three decades, becoming the source of growing concern among education leaders, researchers, and policymakers (Borman & Dowling, 2008; Sutcher, Darling-Hammond & Carver-Thomas, 2016). When a teacher leaves the classroom, they contribute to a host of burdens on the school that must scramble to fill the vacancy, including lower attendance rates, increased disciplinary incidents, and lower test scores (Hanushek, Kain & Rivkin, 2004; Ronfeldt, Loeb, & Wyckoff, 2013).      The problem is especially pronounced in rural, No Excuse charter schools. These schools are found exclusively in low-income communities and are isolated from the social and cultural amenities found in metropolitan areas. Aside from having a smaller pool of qualified, degree-holding teacher applicants, these communities have deeply rooted identities and characteristics that can present challenges to teacher retention (Kaden, Patterson Healy & Adams, 2016; Maranto & Shuls, 2012). When considered in tandem with the fact that No Excuse charter schools often require more from their teachers, the challenge of retaining teachers in these schools is exacerbated (Ash, 2014; Lack, 2009; Torres, 2013).      	This mixed methods study examined teacher retention in these unique schools through teacher interviews and the distribution of a survey to teachers across the country. Analysis of the data identified themes and factors that impact teachers’ decisions to remain in the classroom, migrate to another school, or leave the classroom altogether.      Data was further analyzed using Herzberg’s Motivation-Hygiene theoretical framework, identifying teacher retention factors as satisfiers and dissatisfiers. Both qualitative and quantitative data suggest that there are two primary satisfiers that have a positive impact on teacher retention in these schools: feeling valued and strong principal leadership. Hygiene factors—or dissatisfiers—that had the biggest impact on teacher retention were: improving salary and benefits, improving work-life balance, and having positive relationships with colleagues. Further investment in and emphasis on these factors are recommended as a means to improve teacher retention in these unique schools.
Proton transport through nanoscale corrugations in two-dimensional crystals
Creators: name: Wahab, O. J.
name: Daviddi, E.
name: Xin, B.
name: Sun, P. Z.
name: Griffin, E.
name: Colburn, A. W.
name: Barry, D.
name: Yagmurcukardes, M.
name: Peeters, F. M.
name: Geim, A. K.
name: Lozada-Hidalgo, M.
name: Unwin, P. R.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Chemical Physics (physics.chem-ph)
subject: FOS: Physical sciences

description: Defect-free graphene is impermeable to all atoms and ions at ambient conditions. Experiments that can resolve gas flows of a few atoms per hour through micrometre-sized membranes found that monocrystalline graphene is completely impermeable to helium, the smallest of atoms. Such membranes were also shown to be impermeable to all ions, including the smallest one, lithium. On the other hand, graphene was reported to be highly permeable to protons, nuclei of hydrogen atoms. There is no consensus, however, either on the mechanism behind the unexpectedly high proton permeability or even on whether it requires defects in graphene's crystal lattice. Here using high resolution scanning electrochemical cell microscopy (SECCM), we show that, although proton permeation through mechanically-exfoliated monolayers of graphene and hexagonal boron nitride cannot be attributed to any structural defects, nanoscale non-flatness of 2D membranes greatly facilitates proton transport. The spatial distribution of proton currents visualized by SECCM reveals marked inhomogeneities that are strongly correlated with nanoscale wrinkles and other features where strain is accumulated. Our results highlight nanoscale morphology as an important parameter enabling proton transport through 2D crystals, mostly considered and modelled as flat, and suggest that strain and curvature can be used as additional degrees of freedom to control the proton permeability of 2D materials.
Backreaction of scalar waves on black holes at low frequencies
Creators: name: de Cesare, Marco
name: Oliveri, Roberto
Publisher: name: arXiv
Year: 2023
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We study the accretion of a Schwarzschild black hole due to spherically symmetric perturbations sourced by a minimally coupled massless scalar field. The backreaction of the black hole to low-frequency ingoing scalar waves is computed analytically as a second-order perturbative effect, using matched asymptotic expansions to relate the behaviour of the scalar field in the vicinity of the horizon and at null infinity. As an application of our results, we compute the mass increase due to (i) ingoing wave packets with an arbitrary profile and (ii) incoherent radiation. Our results could serve as a model for the backreaction of environmental scalar fields on black holes.
description: 10 pages, 3 figures; v2: updated references, matches published version in PRD
Fisher matrix forecasts on the astrophysics of galaxies during the epoch of reionisation from the 21-cm power spectra
Creators: name: Balu, Sreedhar
name: Greig, Bradley
name: Wyithe, J. Stuart B.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: The hyperfine 21-cm transition of neutral hydrogen from the early Universe ($z>5$) is a sensitive probe of the formation and evolution of the first luminous sources. Using the Fisher matrix formalism we explore the complex and degenerate high-dimensional parameter space associated with the high-$z$ sources of this era and forecast quantitative constraints from a future 21-cm power spectrum (21-cm PS) detection. This is achieved using MERAXES, a coupled semi-analytic galaxy formation model and reionisation simulation, applied to an $N$-body halo merger tree with a statistically complete population of all atomically cooled galaxies out to $z\sim20$. Our mock observation assumes a 21-cm detection spanning $z \in [5, 24]$ from a 1000 h mock observation with the forthcoming Square Kilometre Array and is calibrated with respect to ultraviolet luminosity functions (UV LFs) at $z\in[5, 10]$, the optical depth of CMB photons to Thompson scattering from Planck, and various constraints on the IGM neutral fraction at $z > 5$. In this work, we focus on the X-ray luminosity, ionising UV photon escape fraction, star formation and supernova feedback of the first galaxies. We demonstrate that it is possible to recover 5 of the 8 parameters describing these properties with better than $50$ per cent precision using just the 21-cm PS. By combining with UV LFs, we are able to improve our forecast, with 5 of the 8 parameters constrained to better than 10 per cent (and all below 50 per cent).
description: 14 pages, 5 figures (+3 appendix), Revised and MNRAS accepted version
Von Bürg nach Basel. Christian Gottlieb Blumhardts Weg zur Basler Mission
Creators: name: Quack, Jürgen
Publisher: name: Universität Tübingen
Year: 2018
Subjects: subject: Mission , Missionswissenschaft , Basel , Württemberg , Kirchengeschichte
subject: 230
subject: Christian Gottlieb Blumhardt
subject: Basler Mission

description: Der württembergische Pfarrer Christian Gottlieb Blumhardt (1779-1838) wurde 1816 zum Leiter der 1815 gegründeten Basler Mission berufen. Schon im Studium in Tübingen (1798-1803) und als Sekretär der Christentumsgesellschaft in Basel (1803-07) hatte er großes Interesse an der Mission. Als Pfarrer in Bürg (1809-16) übersetzte er englische Literatur zur Mission und Bibelverbreitung ins Deutsche. [untranslated]
Y(4260) --> gamma + X(3872) in the diquarkonium picture
Creators: name: Chen, H. -X.
name: Maiani, L.
name: Polosa, A. D.
name: Riquer, V.
Publisher: name: arXiv
Year: 2015
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: The observed Y(4260)\to γ+ X(3872) decay is a natural consequence of the diquark-antidiquark description of Y and X resonances. In this note we attempt an estimate of the transition rate, Γ_{\rm rad}, by a non-relativistic calculation of the electric dipole term of a diquarkonium bound state. We compute Γ_{\rm rad} for generic composition values of the isospin of X and Y. Specializing to I=0 for X(3872), we find Γ_{\rm rad}= 496~keV for Y(4260) with I=0 and Γ_{\rm rad}= 179~keV for I=1. Combining with BESIII data, we derive upper bounds to B(Y\to J/Ψ+π+π) and to Γ(Y\to μ^+ μ^-). We expect to confront these results with forthcoming data from electron-positron and hadron colliders.
description: references added and minor corrections, 11 pages, 1 figure