cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Oxygen Sensing in Lymnaea: from Behaviour to Central Pattern Generators
Creators: name: Janes, Tara Adele
Publisher: name: Graduate Studies
Year: 2016
Subjects: subject: Animal Physiology
subject: Neuroscience
subject: central pattern generators
subject: chemoreception
subject: hypoxia
subject: Lymnaea stagnalis

description: From invertebrates to humans, the regulation of cellular O2 levels within narrow physiological limits represents a significant challenge, but one that is necessary for survival. This essential task of O2 homeostasis is controlled by the nervous system so as to meet metabolic O2 demands in the face of ever-changing environments or injury/disease. The process by which the nervous system exercises such precise control over systemic O2 levels is termed respiratory behaviour. Specialized neural circuits termed respiratory central pattern generators (rCPG’s) produce the basic rhythmic motor output underlying respiratory behaviour. In turn, rCPG activity is subject to extensive neuromodulation, which allows respiratory behaviour to be adapted to changing environments or during various disease states. However, the fundamental mechanisms by which rCPG networks collect and integrate sensory information about the O2 environment and orchestrate a diversity of adaptive behavioural responses remains poorly understood. Specifically, data characterizing the effect of graded hypoxia on respiratory behaviour, locomotion and breathing pattern have not been described for many invertebrate taxa. These data are important as they aid our understanding of fundamental network mechanisms in metazoan respiratory control. Furthermore, while O2 chemoreceptors have been shown to be critical for rCPG modulation and adaptation to hypoxia, the mechanisms of hypoxic signal transduction and O2-sensing, as well as the functional relationship between multiple peripheral and central chemoreceptors remains uncertain. This thesis has sought to fill these gaps in our knowledge using the Lymnaea stagnalis model system wherein the neural correlates of aerial respiratory behaviour have been previously defined. Here, I demonstrate how graded environmental hypoxia produces adaptive changes in Lymnaea aerial respiratory behaviour by altering respiratory parameters, breathing pattern and plasticity. Moreover, I have identified a distributed peripheral O2 chemoreceptive network, which provides significant modulation of rCPG activity. Finally, I have defined the ability of central hypoxia to modulate rCPG activity and connectivity. Taken together, these studies fill significant gaps in fundamental knowledge vis-à-vis the mechanisms by which highly plastic respiratory neural networks collect and integrate information about the O2 environment in order to produce adaptive respiratory behaviour.
Predictors of Mental Health Help-seeking Attitudes among Older Chinese Immigrants
Creators: name: Tieu, Yvonne
Publisher: name: Graduate Studies
Year: 2013
Subjects: subject: Mental Health
subject: Psychology--Clinical
subject: Psychology--Developmental
subject: Older Chinese immigrants
subject: Mental health help-seeking attitudes
subject: Cultural adaptation

description: Chinese older adults are a growing population in Canada and data suggest that they are vulnerable to mental health issues. However, research has noted that older adults, especially ethnic minority seniors, underutilize mental health services. The influence of cultural factors on attitudes toward seeking mental health services may be a barrier to mental health utilization among Chinese older adults. Thus, the primary purpose of this study was to investigate a model of attitudes toward seeking mental health services among Chinese older adults. The secondary purpose of this study was to examine the relationships among mental health help-seeking attitudes, mental health utilization, and intentions to use mental health services among Chinese older adults. The current study assessed an adapted model (Kim, Atkinson, & Umemoto, 2001) of mental health help-seeking attitudes that included the predictors of personal factors (e.g., age, gender), environmental factors (e.g., social support), acculturation (participation in the host culture) and enculturation (maintenance of the heritage culture) among 149 middle-aged and elderly Chinese immigrants in Canada (Mage = 73.92 years; SD = 9.99; range: 55 to 95 years old). Although acculturation and enculturation were distinct processes among Chinese older adults, the model of help-seeking attitudes did not demonstrate good fit when evaluated using structural equation modelling. Acculturation and enculturation did not mediate the relationship among the predictors of age, gender, education, and perceived social support, and mental health help-seeking attitudes. More positive attitudes were evident among younger participants and respondents with better social support, but Chinese older adults had less positive attitudes than comparative samples. Attitudes were not related to seeking help from professionals (e.g. family physician), but were associated with seeking help from non-professionals (e.g., family and friends). In terms of mental health utilization, 8% of participants reported seeking help from a family physician, while 11% had sought help from non-professionals. This is the first study to apply the adapted model (Kim et al., 2001) to older Chinese adults and contributes a number of important findings, despite theoretical and methodological limitations inherent to cross-cultural research. The results of this study provide suggestions for future research and implications for practice.
Multifrequency Variability and Correlations from Extensive Observing Campaigns of Mkn 421 and Mkn 501 in 2009
Creators: name: de Almeida, Ulisses Barres
name: Paneque, David
name: Nowak, Nina
name: Strah, Nikola
name: Tescaro, Diego
Publisher: name: arXiv
Year: 2011
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: We are performing an unprecedentedly long and dense monitoring of the multi-frequency (radio to TeV) emission from the classical TeV blazars Mkn 421 and Mkn 501. These objects are among the brightest X-ray/TeV blazars in the sky and among the few sources whose spectral energy distributions (SED) can be completely characterised by the current instruments. This is a multi-year and multi-instrument programme which includes the participation of VLBA, Swift, RXTE, MAGIC, VERITAS, Whipple, the Fermi/LAT Gamma-ray Observatory, GASP-WEBT, among other collaborations and instruments which combined provide the most detailed temporal and energy coverage of these sources to date. In this proceedings we will focus mostly on the results obtained with the multi-frequency data from 2009, for which the SEDs of Mkn 421 and Mkn 501 are very similar and can be described by a one-zone synchrotron self-Compton scenario. We will report on the multi-frequency variability derived from these data.
description: for the Fermi-LAT, MAGIC and VERITAS Collaborations and other groups involved in the 2009 MWL Campaign. To appear in the proceedings of the 32nd International Cosmic Ray Conference (ICRC), Beijing, China
The Effect of Phosphodiesterase Inhibitors on the Induction of Gene Expression by Long-Acting beta2-Adrenoceptor Agonists and Glucocorticoids
Creators: name: BinMahfouz, Hawazen
Publisher: name: Graduate Studies
Year: 2013
Subjects: subject: Molecular
subject: Phosphodiesterase Inhibitors
subject: Long-Acting beta2-Adrenoceptor
subject: Glucocorticoids
subject: Anti-inflammatory genes
subject: chronic obstructive pulmonary disease

description: Recently, phosphodiesterases (PDE)4 inhibitors have received approval as a complementary anti-inflammatory treatment for chronic obstructive pulmonary disease (COPD) patients who are already taking long-acting β2-agonists (LABA)/inhaled corticosteroid (ICS) combination therapy. However, this benefit is seen only in patients of the severe, bronchitic, frequent exacerbator phenotype. Several strategies have been proposed to enhance the clinical efficacy of PDE4 inhibitors. One of these is the use of dual PDE3/4 inhibitors, which in addition to providing superior anti-inflammatory activity when compared to a PDE4 inhibitor alone, will also promote bronchodilatation. The present study demonstrates that a PDE3 plus a PDE4 inhibitor successfully sensitized BEAS-2B airway epithelial cells transfected with a cyclic adenosine 3',5'-monophosphate (cAMP)-response element luciferase reporter to the LABA, formoterol. Furthermore, PDE3 plus PDE4 inhibitors in combination prolonged and/or sensitized the ability of formoterol to induce several genes in BEAS-2B cells that have anti-inflammatory potential in the absence and presence of the glucocorticoid, dexamethasone. Collectively, these data suggest that LABA/ICS combination therapy in conjunction with an inhibitors of PDE3 and PDE4 may together improve clinical outcomes in larger a population of severe COPD patients.
Kullback Proximal Algorithms for Maximum Likelihood Estimation
Creators: name: Chrétien, Stéphane
name: Hero, Alfred O.
Publisher: name: arXiv
Year: 2012
Subjects: subject: Computation (stat.CO)
subject: FOS: Computer and information sciences

description: Accelerated algorithms for maximum likelihood image reconstruction are essential for emerging applications such as 3D tomography, dynamic tomographic imaging, and other high dimensional inverse problems. In this paper, we introduce and analyze a class of fast and stable sequential optimization methods for computing maximum likelihood estimates and study its convergence properties. These methods are based on a {\it proximal point algorithm} implemented with the Kullback-Liebler (KL) divergence between posterior densities of the complete data as a proximal penalty function. When the proximal relaxation parameter is set to unity one obtains the classical expectation maximization (EM) algorithm. For a decreasing sequence of relaxation parameters, relaxed versions of EM are obtained which can have much faster asymptotic convergence without sacrifice of monotonicity. We present an implementation of the algorithm using Moré's {\it Trust Region} update strategy. For illustration the method is applied to a non-quadratic inverse problem with Poisson distributed data.
description: 6 figures
Synchrotron X-ray phase-contrast imaging of ultrasonic drop atomization
Creators: name: Prasanna, Anunay
name: Biasiori-Poulanges, Luc
name: Yu, Ya-Chi
name: El-Rabii, Hazem
name: Lukić, Bratislav
name: Supponen, Outi
Publisher: name: arXiv
Year: 2023
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Physical sciences

description: Ultrasonic atomization is employed to generate size-controllable droplets for a variety of applications. Here, we minimize the number of parameters dictating the process by studying the atomization of a single drop pending from an ultrasonic horn. Spatiotemporally resolved X-ray phase-contrast imaging measurements show that the number-median sizes of the ejected droplets can be predicted by the linear Navier-Stokes equations, signifying that the size distribution is controlled by the fluid properties and the driving frequency. Experiments with larger pendant water drops indicate that the fluid-structure interaction plays a pivotal role in determining the ejection onset of the pendant drop. The atomization of viscoelastic drops is dictated by extended ligament formation, entrainment of air, and ejection of drop-encapsulated bubbles. Existing scaling laws are used to explain the required higher input amplitudes for the complete atomization of viscoelastic drops as compared to inviscid drops. Finally, we elucidate the differences between capillary wave-based and cavitation-based atomization and show that inducing cavitation and strong bubble oscillations quickens the onset of daughter drop ejection but impedes their size control.
description: 36 pages, 11 figures
Background, foreground and nearby matter influence on strong gravitational lenses
Creators: name: Jaroszynski, M.
name: Kostrzewa-Rutkowska, Z.
Publisher: name: arXiv
Year: 2012
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We investigate strong lensing by non-singular finite isothermal ellipsoids taking into account the influence of the matter along the line of sight and in the close lens vicinity. We compare three descriptions of light propagation: the full approach taking into account all matter inhomogeneities along the rays, the single plane approach, where we take into account the influence of the strong lens neighbours but neglect the foreground and background objects, and the single lens approach. In each case we simulate many strong lensing configurations placing a point source at the same redshift but in different locations inside the region surrounded by caustics. We further analyze configurations of four or five images. For every simulated strong lensing configuration we attempt to fit a simplified lens model using a single isothermal ellipsoid or a single isothermal ellipsoid with external shear. The single lens fits to configurations obtained in the full approach are rejected in majority of cases with 95% significance. For configurations obtained in the single plane approach the rejection rate is substantially lower. Also the inclusion of external shear in simplified modeling improves the chances of obtaining acceptable fits, but the problem is not solved completely. The quantitative estimates of the rates of rejection of simplified models depend on the required accuracy of the models, and we present few illustrative examples, which show that both matter close to the lens and matter along the rays do have important influence on lens modeling. We also estimate the typical value of the external shear and compare the fitted parameters of the simplified models with the parameters of the lenses used in the simulations.
description: Accepted for publication in MNRAS; 8 pages, 5 figures
Chasing the loss: Factors that predict within- and between-session chasing in gamblers
Creators: name: Yakovenko, Igor
Publisher: name: Graduate Studies
Year: 2017
Subjects: subject: Psychology
subject: FOS: Psychology
subject: Psychology--Clinical
subject: gambling
subject: disordered gambling
subject: chasing

description: One of the hallmark features of disordered gambling is ‘chasing’, defined as an urge to continue playing within a single gaming session or come back at another time to attempt to recover lost money. To date, limited research has been conducted to delineate specific predictors of increased chasing behaviour in both disordered and social gamblers. The present study attempted to answer two questions: 1) which personality, physiological, and cognitive variables predict increased within- and between- session chasing behaviour in disordered and social gamblers? 2) In what ways do disordered and social gamblers differ with regard to predictors of chasing? 111 participants recruited in the community, divided into social and disordered gamblers, gambled on a realistic slot machine with predetermined outcomes. Variables relating to disordered gambling severity, dissociation, emotional vulnerability, cognitive distortions, impulsivity, substance use, and craving for gambling and other substances were assessed as predictors of between- and within-session chasing. Results support the association of chasing behaviour with dissociation, gambling problem severity, emotional vulnerability, and impulsivity. However, inconsistencies in some results point to difficulties in reliability of operationalizing chasing. The results also put in question the validity of using retrospective self-report to assess chasing. The overall findings support chasing as operating on a continuum of severity with social gamblers chasing in limited amounts and disordered gamblers chasing in greater amounts. In addition, qualitative feedback from participants challenges the utility of in-lab gambling as a proxy of real-world gambling conditions. Implications for research, policy and treatment of disordered gambling are discussed and recommendations for future research are provided.
Evidence of Deterministic Components in the Apparent Randomness of GRBs: Clues of a Chaotic Dynamic
Creators: name: Greco, G.
name: Rosa, R.
name: Beskin, G.
name: Karpov, S.
name: Romano, L.
name: Guarnieri, A.
name: Bartolini, C.
name: Bedogni, R.
Publisher: name: arXiv
Year: 2011
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: Prompt γ-ray emissions from gamma-ray bursts (GRBs) exhibit a vast range of extremely complex temporal structures with a typical variability time-scale significantly short - as fast as milliseconds. This work aims to investigate the apparent randomness of the GRB time profiles making extensive use of nonlinear techniques combining the advanced spectral method of the Singular Spectrum Analysis (SSA) with the classical tools provided by the Chaos Theory. Despite their morphological complexity, we detect evidence of a non stochastic short-term variability during the overall burst duration - seemingly consistent with a chaotic behavior. The phase space portrait of such variability shows the existence of a well-defined strange attractor underlying the erratic prompt emission structures. This scenario can shed new light on the ultra-relativistic processes believed to take place in GRB explosions and usually associated with the birth of a fast-spinning magnetar or accretion of matter onto a newly formed black hole.
description: 13 pages, 6 figures
AXIOM: Advanced X-ray Imaging Of the Magnetosphere
Creators: name: Branduardi-Raymont, G.
name: Sembay, S. F.
name: Eastwood, J. P.
name: Sibeck, D. G.
name: Abbey, A.
name: Brown, P.
name: Carter, J. A.
name: Carr, C. M.
name: Forsyth, C.
name: Kataria, D.
name: Kemble, S.
name: Milan, S. E.
name: Owen, C. J.
name: Peacocke, L.
name: Read, A. M.
name: Coates, A. J.
name: Collier, M. R.
name: Cowley, S. W. H.
name: Fazakerley, A. N.
name: Fraser, G. W.
name: Jones, G. H.
name: Lallement, R.
name: Lester, M.
name: Porter, F. S.
name: Yeoman, T. K.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: Planetary plasma and magnetic field environments can be studied by in situ measurements or by remote sensing. While the former provide precise information about plasma behaviour, instabilities and dynamics on local scales, the latter offers the global view necessary to understand the overall interaction of the magnetospheric plasma with the solar wind. Here we propose a novel and more elegant approach employing remote X-ray imaging techniques, which are now possible thanks to the relatively recent discovery of solar wind charge exchange X-ray emissions in the vicinity of the Earth's magnetosphere. We describe how an appropriately designed and located X-ray telescope, supported by simultaneous in situ measurements of the solar wind, can be used to image the dayside magnetosphere, magnetosheath and bow shock, with a temporal and spatial resolution sufficient to address several key outstanding questions concerning how the solar wind interacts with the Earth's magnetosphere on a global level. Our studies have led us to propose 'AXIOM: Advanced X-ray Imaging Of the Magnetosphere', a concept mission using a Vega launcher with a LISA Pathfinder-type Propulsion Module to place the spacecraft in a Lissajous orbit around the Earth - Moon L1 point. The model payload consists of an X-ray Wide Field Imager and an in situ plasma and magnetic field measurement package. This package comprises sensors designed to measure the bulk properties of the solar wind and to characterise its minor ion populations which cause charge exchange emission, and a magnetometer designed to measure the strength and direction of the solar wind magnetic field. We show simulations that demonstrate how the proposed X-ray telescope design is capable of imaging the predicted emission from the dayside magnetosphere with the sensitivity and cadence required to achieve the science goals of the mission.
description: Published in Experimental Astronomy, Springer (40 pages, 14 figures, 5 tables). Updated version re-submitted to arXiv on 1 August 2011 (with corrected figure numbering and improved versions of Fig.s 4, 7, 10, 11); http://www.springerlink.com/openurl.asp?genre=article&id=doi:10.1007/s10686-011-9239-0 (published on-line, July 2011)
Prospects for Taiji to detect a gravitational-wave background from cosmic strings
Creators: name: Chen, Zu-Cheng
name: Huang, Qing-Guo
name: Liu, Chang
name: Liu, Lang
name: Liu, Xiao-Jin
name: Wu, You
name: Wu, Yu-Mei
name: Yi, Zhu
name: You, Zhi-Qiang
Publisher: name: arXiv
Year: 2023
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: Recently, multiple pulsar timing array collaborations have presented compelling evidence for a stochastic signal at nanohertz frequencies, potentially originating from cosmic strings. Cosmic strings are linear topological defects that can arise during phase transitions in the early Universe or as fundamental strings in superstring theory. This paper focuses on investigating the detection capabilities of Taiji, a planned space-based gravitational wave detector, for the gravitational wave background generated by cosmic strings. By analyzing simulated Taiji data and utilizing comprehensive Bayesian parameter estimation techniques, we demonstrate a significant improvement in precision compared to the NANOGrav 15-year data, surpassing it by an order of magnitude. This highlights the enhanced measurement capabilities of Taiji. Consequently, Taiji can serve as a valuable complementary tool to pulsar timing arrays in validating and exploring the physics of cosmic strings in the early Universe.
description: 24 pages, 5 figures
Multi-Resolution Spectral Techniques for Static DGPS Error Analysis and Mitigation
Creators: name: El-Ghazouly, Ahmed Adel
Publisher: name: Graduate Studies
Year: 2013
Subjects: subject: Geodesy
subject: Civil
subject: DGPS
subject: Wavelet
subject: Multiresolution
subject: Code-smoothing
subject: cycle slip

description: GPS measurements can be modeled as a true range plus other errors such as orbital and clock biases, atmospheric residual, multipath, and observation noise. Modeling is one way to deal with some of these errors, if their characteristics are known (e.g. troposphere and ionosphere errors). Another way is to filter in the frequency domain, where all these errors have a different frequency spectrum component. Each error is characterized by a specific frequency band. For example, the receiver noise can be characterized with high frequency components, multipath errors, which have low to medium frequency bands, while the ionospheric and tropospheric errors are at a lower frequency band. Wavelet spectral techniques can separate GPS signals into sub-bands where different errors can be separated and mitigated. Using wavelets to transform the GPS measurements into frequency domain helps localize both location and frequency of GPS errors, which allows for easy error separation in frequency domain. This thesis introduces new wavelet spectral analysis techniques to mitigate DGPS errors in the frequency domain, namely cycle slip, code and phase multipath errors. The wavelet-based trend extraction model is applied to DGPS static baseline solutions and compared with the traditional de-noising technique. The de-trending methodology performed impressively for short baselines in RMS and bias reduction as the average RMS and bias reductions were around 80%. However, for longer baselines the bias reduction is minimal although the RMS reduction is still in the 70-80% reduction. A second approach is introduced to detect and remove cycle slip errors, which can be seen as a singularity in the GPS data. The propagation of singularities between the levels of wavelet decomposition is different from the propagation of noise. This characteristic is used to identify the singularities from noise. The performance of the multi-scale singularity detection technique is evaluated and tested over GPS Code minus Carrier (CmC) and Phase1 minus Phase2 measurements where different cycle slips are added to the measurements. All the simulated cycle slips in CmC test quantities with SNR larger than 30 are effectively detected by the proposed technique. The error in the estimation process is, in most instances, less than 0.1 cycles. Finally, the Multi-resolution Real-time (MRRT) Code-smoothing technique is introduced to real-time scenarios to mitigate code multipath error (medium to high-frequency) and noise (high-frequency) and retain the ionospheric error (low-frequency) untouched in the mitigation.
Growing Extended Laughlin States in a Quantum Gas Microscope: A Patchwork Construction
Creators: name: Palm, Felix A.
name: Kwan, Joyce
name: Bakkali-Hassani, Brice
name: Greiner, Markus
name: Schollwöck, Ulrich
name: Goldman, Nathan
name: Grusdt, Fabian
Publisher: name: arXiv
Year: 2023
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: The study of fractional Chern insulators and their exotic anyonic excitations poses a major challenge in current experimental and theoretical research. Quantum simulators, in particular ultracold atoms in optical lattices, provide a promising platform to realize, manipulate, and understand such systems with a high degree of controllability. Recently, an atomic $ν=1/2$ Laughlin state has been realized experimentally for a small system of two particles on 4 by 4 sites. The next challenge concerns the preparation of Laughlin states in extended systems, ultimately giving access to anyonic braiding statistics or gapless chiral edge-states in systems with open boundaries. Here, we propose and analyze an experimentally feasible scheme to grow larger Laughlin states by connecting multiple copies of the already existing 4-by-4-system. First, we present a minimal setting obtained by coupling two of such patches, producing an extended 8-by-4-system with four particles. Then, we analyze different preparation schemes, setting the focus on two shapes for the extended system, and discuss their respective advantages: While growing strip-like lattices could give experimental access to the central charge, square-like geometries are advantageous for creating quasi-hole excitations in view of braiding protocols. We highlight the robust quantization of the fractional quasi-hole charge upon using our preparation protocol. We benchmark the performance of our patchwork preparation scheme by comparing it to a protocol based on coupling one-dimensional chains. We find that the patchwork approach consistently gives higher target-state fidelities, especially for elongated systems. The results presented here pave the way towards near-term implementations of extended Laughlin states in quantum gas microscopes and the subsequent exploration of exotic properties of topologically ordered systems in experiments.
description: 18 pages, 21 figures
Operating a zero-carbon GB power system: implications for Scotland
Creators: name: Nedd, Marcel
name: Browell, Jethro
name: Egea-Alvarez, Agusti
name: Bell, Keith
name: Hamilton, Robert
name: Wang, Shuren
name: Brush, Susan
Publisher: name: University of Strathclyde
Year: 2020
Subjects: zero-carbon
electricity generation
electricity networks
power systems
Great Britain

description: In recent history, the British electricity sector landscape has changed as more renewables, particularly solar and wind, are connected to the power system. Since 2004, electricity generated from renewables in the UK has increased tenfold, and in 2019 37.1% of total electricity generated was from renewable sources. These changes have far-reaching implications for the operation of national electricity networks and for ensuring security of supply. Current and emerging system operability concerns in GB cover a broad range of topics. Work recently completed at the University of Strathclyde, outlined in this report, has reviewed: how the British Electricity System Operator, National Grid ESO (NGESO) currently uses balancing services to manage the power system; possibilities for the future provision of frequency response and reserve; prospects for short circuit current support from power electronic converters; and market changes required to avoid the need for NGESO to constrain on fossil-fuelled generation to support system operability in 2025.
School District Effect on Principal Instructional Leadership Efficacy
Creators: name: Keeping, George Thomas
Publisher: name: Graduate Studies
Year: 2017
Subjects: subject: Education--Administration
subject: district growth culture
subject: collaborative learning structures
subject: central office administrator support
subject: data use
subject: technical skills as efficacy enhancing
subject: administrator autonomy

description: Abstract This qualitative multiple-case study examined district and other antecedents that contribute to principal instructional leadership efficacy. With increased demands that schools better prepare students for a more complex society, principals need to be able to remain focused on the quality of instruction using a more collaborative, distributed form of leadership. They need to target their own energy and efforts on things that really make a difference. Using a conceptual framework based on sociocognitive theory as well as district and instructional leadership, the research explored how districts currently contribute to principal instructional leadership efficacy and makes recommendations for district improvement and for further academic research. Five principals and 5 district office central office administrators were interviewed to ascertain school district factors that positively impact principal instructional leadership efficacy. As well, factors other than those that were perceived as district related that appeared to affect principal instructional leadership efficacy were brought to light. Three overarching themes arose from the findings. Districts enhance principal efficacy through (a) a district growth culture that provides overarching efficacy support, (b) the support and development of collaborative learning structures, and (c) the provision of district human and financial resources that promote principal autonomy and provide pressure and support. Recommendations include the need to strengthen the cooperation between the Department of Education and Early Childhood Development to create more robust data systems for principals and the need for in-service efficacy training for principals and school district central office administrators.
The Effects of Free Radical-induced Epoxidation and Peroxidation of Unsaturated Phospholipids on the Self-assembly of Functional Surfactant Film
Creators: name: Al-Saiedy, Mustafa
Publisher: name: Graduate Studies
Year: 2016
Subjects: subject: Biophysics--Medical
subject: Chemistry--Organic
subject: ARDS
subject: ALI
subject: CF
subject: Surfactant
subject: Lung
subject: Pulmonary
subject: Inflammation
subject: cholesterol
subject: Oxidation
subject: ROS
subject: Dysfunction

description: The pulmonary surfactant is a protein-lipid mixture that covers the air-water interface. It lowers the alveolar surface tension to near zero values. Surfactant dysfunction has been reported in acute lung injury, acute respiratory distress syndrome, and cystic fibrosis, among other inflammatory lung diseases. Surfactant achieves low surface tension by forming a tightly packed uniform film at the air-water interface and thus, eliminates the electrostatic forces between liquid molecules. As the film pressure (π) increase, surfactant explores a third dimension or multilayers. Monolayer-Multilayer interactions provide additional stability to resist the varying high film pressure at the air-water interface, therefore, preventing premature buckling of the interfacial film. The surfactant may become impaired during pulmonary inflammation, where free radicals degrade its components, whether by introducing epoxides and hydroperoxides to the tightly packed hydrocarbon tails of surfactant phospholipids or by fatty acyl tail fragmentation. In this thesis, we show that oxidation mediated surfactant inhibition is cholesterol dependent. We study surfactant film thermodynamic changes as a result of oxidation and cholesterol. Additionally, we show the structure-function relationship and the underlying importance of monolayer-multilayer anchoring. Moreover, we show that multilayer distribution and arrangements due to oxidized cholesterol species do not alter surfactant film function. Further, we modeled the surfactant film via mechanical finite element analysis software (ANSYS) to examine the role of multilayers. We predict that the mechanism of surfactant dysfunction demonstrated in vitro is relevant to disease state.
Candidate toroidal electric dipole mode in the spherical nucleus $^{58}$Ni
Creators: name: von Neumann-Cosel, P.
name: Nesterenko, V. O.
name: Brandherm, I.
name: Vishnevskiy, P. I.
name: Reinhard, P. -G.
name: Kvasil, J.
name: Matsubara, H.
name: Repko, A.
name: Richter, A.
name: Scheck, M.
name: Tamii, A.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Nuclear Experiment (nucl-ex)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: Dipole toroidal modes appear in many fields of physics. In nuclei, such a mode was predicted more than 50 years ago, but clear experimental evidence was lacking so far. Using a combination of high-resolution inelastic scattering experiments with photons, electrons and protons, we identify for the first time candidates for toroidal dipole excitations in the nucleus $^{58}$Ni and demonstrate that transverse electron scattering form factors represent a relevant experimental observable to prove their nature.
description: 13 pages, 8 figures
The Effectiveness of Implicit and Explicit Instruction on German L2 Learners’ Pronunciation
Creators: name: Peltekov, Petar
Publisher: name: Graduate Studies
Year: 2017
Subjects: subject: Education
subject: Education--Adult and Continuing
subject: Education--Bilingual and Multicultural
subject: Education--Higher
subject: Language
subject: Language--Modern
subject: Literature--Modern
subject: Literature--English
subject: Literature--Germanic
subject: German
subject: pronunciation
subject: implicit
subject: explicit
subject: methodology
subject: Teaching
subject: Learning
subject: phonetics
subject: accent
subject: comprehensibility

description: Previous research has investigated the effectiveness of implicit and explicit instructional methods on second language (L2) learners’ grammatical accuracy. However, there is a scarcity of studies focused on the effects of the two teaching methods on L2 learners’ pronunciation. To fill this gap, the present thesis examines the effects of implicit and explicit instruction on the pronunciation of beginner learners of German. One group of learners was taught pronunciation explicitly (i.e., using phonetic rules), another group—implicitly (i.e., without phonetic rules), and a third group received no pronunciation instruction. A pretest-posttest design was used to measure learners’ improvement in accent and comprehensibility. No significant difference in progress was found across the three groups. The findings suggest that learner variables might be better predictors of improvement than the type of instruction. Moreover, not all pronunciation features were equally relevant for L2 learners’ comprehensibility. The results have implications for L2 pronunciation teaching.
Variational stabilization of degenerate p-elasticae
Creators: name: Miura, Tatsuya
name: Yoshizawa, Kensuke
Publisher: name: arXiv
Year: 2023
Subjects: subject: Analysis of PDEs (math.AP)
subject: Differential Geometry (math.DG)
subject: FOS: Mathematics
subject: 49Q10, 53A04, and 33E05

description: A new stabilization phenomenon induced by degenerate diffusion is discovered in the context of pinned planar $p$-elasticae. It was known that in the non-degenerate regime $p\in(1,2]$, including the classical case of Euler's elastica, there are no local minimizers other than unique global minimizers. Here we prove that, in stark contrast, in the degenerate regime $p\in(2,\infty)$ there emerge uncountably many local minimizers with diverging energy.
description: 23 pages, 3 figures, final version
Almost Lie structures on an anchored Banach bundle
Creators: name: Cabau, Patrick
name: Pelletier, Fernand
Publisher: name: arXiv
Year: 2011
Subjects: subject: Differential Geometry (math.DG)
subject: FOS: Mathematics

description: Under appropriate assumptions, we generalize the concept of linear almost Poisson struc- tures, almost Lie algebroids, almost differentials in the framework of Banach anchored bundles and the relation between these objects. We then obtain an adapted formalism for mechanical systems which is illustrated by the evolutionary problem of the "Hilbert snake"
Body-Centric Interaction with Wall Displays in Multi-Display Environments
Creators: name: Zochodne, Julia
Publisher: name: Graduate Studies
Year: 2017
Subjects: subject: Computer Science
subject: large displays
subject: interaction techniques
subject: proxemics
subject: Gestures
subject: Touch
subject: multi-display environment

description: Large wall displays have become increasingly widespread, and they can be used in diverse environments to support information sharing and collaboration. Wall displays can also be easily incorporated into multi-display environments, allowing for information exchange between the wall display and personal devices, such as tablets. However, traditional input devices such as the mouse and keyboard present challenges for these types of displays, including problems with window and task management, navigation, as well as selecting individual regions or items. Different techniques should be investigated in order to effectively interact with these large displays. In this thesis we perform a study comparing the effectiveness of interaction techniques with large wall displays including body-centric techniques (i.e. proxemics and mid-air gestures) and interaction involving secondary devices (i.e. tablets). Participants were given tasks involving different permutations of these interaction techniques, and the results were evaluated using a quantitative measure of task completion time, and qualitative data gathered from post-study interviews and questionnaires. We found that the fastest interaction technique was touch interaction with a tablet, where the tablet was used to control the large wall display. The study also showed that touch selection was most preferred by users in terms of usability.
A new role for the tumour suppressor LIN-35 during meiotic recombination in Caenorhabditis elegans
Creators: name: Lohn, Zoe Roy
Publisher: name: University of British Columbia
Year: 2011

description: Meiosis is a fundamental biological process used by sexually reproducing species to ensure the faithful transmission of genetic material and to generate genetic diversity. In humans, failure to recombine properly during meiosis causes genetic conditions in the human conceptus such as aneuploidy and spontaneous abortion. An excellent model organism for the investigation of meiotic recombination is the nematode, Caenorhabditis elegans, which has many conserved meiotic processes. In this thesis, I have investigated the role of lin-35 in meiotic crossing over. LIN-35 is the C. elegans ortholog of the retinoblastoma (Rb) protein, well characterized with respect to its role in gene transcription and cell proliferation. My results show that mutation in the lin-35 gene alters recombination frequency differentially for several regions of the chromosome, causing increases in recombinationally suppressed regions and decreases in highly recombinogenic regions. In combination with Rec-1, a mutant known to alter crossover distribution, crossovers across the length of the entire chromosome, were decreased. In addition, other severely detrimental phenotypes were observed. For example, gametic viability was reduced dramatically in the double mutant, compared to either mutant alone. Thus, the Lin-35 and Rec-1 phenotypes were synergistic, indicating non-redundancy. In summary, lin-35 function plays a role in achieving normal levels of meiotic recombination, a role that may be related to its function in chromatin modification and gene transcription.
Electroluminescence and Energy Transfer Mediated by Hyperbolic Polaritons
Creators: name: Abou-Hamdan, L.
name: Schmitt, A.
name: Bretel, R.
name: Rossetti, S.
name: Tharrault, M.
name: Mele, D.
name: Pierret, A.
name: Rosticher, M.
name: Taniguchi, T.
name: Watanabe, K.
name: Maestre, C.
name: Journet, C.
name: Toury, B.
name: Garnier, V.
name: Steyer, P.
name: Edgar, J. H.
name: Janzen, E.
name: Berroir, J-M.
name: Fève, G.
name: Ménard, G.
name: Plaçais, B.
name: Voisin, C.
name: Hugonin, J-P.
name: Bailly, E.
name: Vest, B.
name: Greffet, J-J.
name: Bouchon, P.
name: De Wilde, Y.
name: Baudin, E.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Under high electrical current, some materials can emit electromagnetic radiation beyond incandescence. This phenomenon, referred to as electroluminescence, leads to the efficient emission of visible photons and is the basis of domestic lighting devices (e.g., light-emitting diodes). In principle, electroluminescence can lead to mid-infrared (mid-IR) emission of confined light-matter excitations called phonon-polaritons, resulting from the coupling of photons with crystal lattice vibrations (optical phonons). In particular, phonon-polaritons arising in the van der Waals crystal hexagonal boron nitride (hBN) exhibit hyperbolic dispersion, which enhances light-matter coupling. For this reason, electroluminescence of hyperbolic phonon-polaritons (HPhPs) has been proposed as an explanation for the peculiar radiative energy transfer within hBN-encapsulated graphene transistors. However, since HPhPs are confined, they are inaccessible in the far-field, so that any hint of electroluminescence is only based on indirect electronic signatures and needs to be confirmed by direct observation. Here, we demonstrate far-field mid-IR (λ = 6.5 μm) electroluminescence of HPhPs excited by strongly biased high-mobility graphene within a van der Waals heterostructure, and we quantify the associated radiative energy transfer through the material. The presence of HPhPs is revealed via far-field mid-IR spectroscopy due to their elastic scattering at discontinuities in the heterostructure. The associated radiative flux is quantified by mid-IR pyrometry of the substrate receiving the energy. This radiative energy transfer is shown to be reduced in hBN with nanoscale inhomogeneities, demonstrating the central role of the electromagnetic environment in this process.
description: 32 pages including Extended Data and Supplementary Material (Main text: 7 pages, 4 figures)
Efficient Pricing Methods in The Cloud Computing Market
Creators: name: Soleimani, Maryam
Publisher: name: Graduate Studies
Year: 2017
Subjects: subject: Computer Science
subject: Cloud Computing
subject: Auction Mechanism
subject: Pricing Methods
subject: Online Algorithm

description: The emerging cloud computing paradigm enables cloud systems to provide multiple heterogeneous types of cloud resources for end customers over a network. Users and providers in these systems attempt to maximize their revenue using well-designed pricing methods. Auctions are considered as efficient mechanisms for resource sharing and charging users in cloud systems. We study the online social welfare maximization problem at a cloud market, and design efficient pricing functions to be used in online auction mechanisms for cloud resource provisioning, for tasks with completion deadlines. Combining the techniques of primal-dual approximation algorithm design with our proposed pricing methods, we design a cloud auction that runs efficiently in polynomial time, guarantees truthfulness, and achieves near-optimal social welfare, in the cloud eco-system. Simulation studies con rm the efficacy of the proposed mechanism.
Constraining the Graviton Mass with the NANOGrav 15-Year Data Set
Creators: name: Wu, Yu-Mei
name: Chen, Zu-Cheng
name: Bi, Yan-Chen
name: Huang, Qing-Guo
Publisher: name: arXiv
Year: 2023
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: The recently detected stochastic signal by several pulsar timing array collaborations, offers an opportunity to scrutinize the fundamental properties of gravity, including the potential mass of the graviton. In this study, we analyze the NANOGrav 15-year data set to search for a stochastic gravitational wave background with modified Hellings-Downs correlations predicted by massive gravity. While the Bayesian analysis comparing the massive gravity to massless gravity within the effective searchable mass range of $m_g\in [3\times 10^{-25}, 8 \times 10^{-24}]\,\rm{eV}/c^2$ does not yield an explicit upper bound as all the Bayes factors are smaller than $3$, the combined consideration of the minimum frequency inherent in a massive gravity and the observed spectrum leads to an upper limit of $m_g<8.2\times 10^{-24}\,\rm{eV}/c^2$.
description: 6 pages, 1 figure, 1 table
Constraints on the velocity of gravitational waves from NANOGrav 15-year data set
Creators: name: Bi, Yan-Chen
name: Wu, Yu-Mei
name: Chen, Zu-Cheng
name: Huang, Qing-Guo
Publisher: name: arXiv
Year: 2023
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: General relativity predicts that gravitational waves propagate at the speed of light. Although ground-based gravitational-wave detectors have successfully constrained the velocity of gravitational waves in the high-frequency range, extending this constraint to the lower frequency range remains a challenge. In this work, we utilize the deviations in the overlap reduction function for a gravitational-wave background within pulsar timing arrays to investigate the velocity of gravitational waves in the nanohertz frequency band. By analyzing the NANOGrav 15-year data set, we obtain a well-constrained lower bound for the velocity of gravitational waves that $v \gtrsim 0.87\,c$, where $c$ is the speed of light.
description: 6 pages, 1 figure, 1 table