cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Growth and structure of yttrium sesquioxide epitaxial films
Creators: name: Webster, Scott Elliott
Publisher: name: University of British Columbia
Year: 2012

description: The use of molecular beam epitaxy as a method for producing solid state host crystals for planar waveguide lasers has been investigated. Single crystal yttrium sesquioxide with a very high degree of structural order has been grown on R-plane sapphire substrates. The (01Ῑ2) Al₂O₃ substrates were annealed in air at 1150°C to generate atomically smooth surfaces with parallel atomic steps. This process was important for maximizing structural quality and minimizing surface roughness of the grown Y₂O₃ ﬁlm. A critical-thickness-like phenomenon was discovered, where the Y₂O₃ would grow in regions with near structural perfection at the beginning of growth. In thicker ﬁlms, the x-ray diffraction peaks became wider, indicating less crystalline uniformity. The maximum equivalent “critical thickness” achieved was 7 nm for a ﬁlm grown at 800°C with a growth rate of 20 nm/hr. The highly ordered material may be present in one uniform layer or distributed in smaller regions throughout the thin ﬁlm. Y₂O₃ ﬁlms on Al₂O₃ were annealed in air at temperatures up to 1400°C to study interdiffusion. By analyzing x-ray diffraction measurements, we found that Al migrated from the substrate into the Y₂O₃ ﬁlm with an approximate activation energy for bulk diffusion of 3.0 eV. Diffusion on the Y₂O₃ surface was estimated to have an activation energy of (0.5 ± 0.3) eV from atomic force microscopy images. After annealing, the presence of Y₄Al₂O₉, YAlO₃, and Y₃Al₅O₁₂ phases was conﬁrmed using x-ray diffraction and photoluminescence measurements. Attempts were made to use molecular hydrogen gas and gallium as surfactants during growth to improve ﬁlm properties. No conclusive beneﬁt was observed. Y₂O₃ ﬁlm surface roughness was observed to increase roughly proportionally to the square root of ﬁlm thickness. A 600 nm thick waveguide layer grown under optimal conditions had a root-mean-square roughness of 5.8 nm. This level of roughness could cause scattering loss at the waveguide core-cladding interface that is problematic for practical applications.
A Semi-Supervised Framework for Misinformation Detection
Creators: name: Liu, Yueyang
name: Boukouvalas, Zois
name: Japkowicz, Nathalie
Publisher: name: arXiv
Year: 2023
Subjects: subject: Artificial Intelligence (cs.AI)
subject: FOS: Computer and information sciences

description: The spread of misinformation in social media outlets has become a prevalent societal problem and is the cause of many kinds of social unrest. Curtailing its prevalence is of great importance and machine learning has shown significant promise. However, there are two main challenges when applying machine learning to this problem. First, while much too prevalent in one respect, misinformation, actually, represents only a minor proportion of all the postings seen on social media. Second, labeling the massive amount of data necessary to train a useful classifier becomes impractical. Considering these challenges, we propose a simple semi-supervised learning framework in order to deal with extreme class imbalances that has the advantage, over other approaches, of using actual rather than simulated data to inflate the minority class. We tested our framework on two sets of Covid-related Twitter data and obtained significant improvement in F1-measure on extremely imbalanced scenarios, as compared to simple classical and deep-learning data generation methods such as SMOTE, ADASYN, or GAN-based data generation.
Writing Microbiology Resource Announcements (MRA)
Creators: name: Diaz, Arturo
name: Lee-Soety, Julia
name: Chaudhary, Shima
name: Monti, Denise
name: Sivanathan, Viknesh
name: Pollenz, Richard
name: Kanak, Alison
name: Sprenkle, Amy
name: Beyer, Andrea
name: Kirkpatrick, Bridgette
name: Twichell, Carole
name: Byrum, Christine
name: Tobiason, Deborah
name: Edwards, Dustin
name: Godin, Elizabeth
name: Savage, Emily
name: Lindberg, Heather
name: Nance, Holly
name: Rocheleau, Jessica
name: Garcia, Julie
name: Dye, Kathryn
name: Butela, Kristen
name: Bono, Lisa
name: Mastropaolo, Matthew
name: Dennis, Megan
name: Rowland, Naomi
name: Vega, Quinn
name: Alvarez, Regina
name: Ng, Rocky
name: Plymale, Ruth
name: Markov, Sergei
name: Caruso, Steven
name: Stoulig, Tara
name: Perez, Tiara
name: Ware, Vassie
name: Delesalle, Veronique
name: Rudner, Adam
name: Wilkes, Beth
name: Bancroft, Christa
name: Fleischacker, Christine
name: Engstrom, Eric
name: Baliraine, Frederick
name: Kotturi, Hari
name: Washington, Jacqueline
name: Shanks, James
name: Hughes, Lee
name: Fisher, Matthew
name: Connerly, Pamela
name: Waikel, Patricia
name: Reardon, Sarah
name: Coleman, Sean
name: Page, Shallee
name: Agrawal, Swati
name: Adair, Tamarah
name: Ndolo, Thomas
name: Jerby, Alexandra
name: Freise, Amanda
name: Costas, Amaya
name: Fillman, Christy
name: Bowder, Dane
name: Westholm, Daniel
name: Williams, Daniel
name: Wisner, Ellen
name: Guerrero, Jennifer
name: Stukey, Joseph
name: Klyczek, Karen
name: Clase, Kari
name: Gainey, Maria
name: AYUK, MARY
name: Antunes, Mauricio
name: Bortz, Rebecca
name: Cresawn, Steven
name: Bhalla, Suparna
name: Frost, Victoria
name: Sunnen, C.
name: Balish, Mitchell
name: Pickett, Brett
name: Rinehart, Claire
name: Actis, Luis
name: Valentine, Megan
name: Gleichsner, Alyssa
name: Harrison, Melissa
name: Broderick, Jennifer
name: Molloy, Sally
name: Zegers, Gerry
name: Stees, Jared
name: Thoemke, Kara
name: King, Rodney
name: Williams, Liz
name: Mitchell, Jon
name: Rombold, John
name: Tchedre, Kissaou
name: Vazquez, Edwin
name: Gusky, Sharon
name: Eivazova, Elvira
name: Dotson, Dominique
name: Mussi, Alejandra
name: Kagey, Jacob
name: DeJong, Randy
name: Ward, Catherine
name: Hare, Rebekah
name: Kohl, Kathryn
name: Nsa, Imade
name: Bouklas, Tejas
name: Tolsma, Sarah
name: Berkes, Charlotte
name: Neely, Melody
name: Danley, Aimee
Publisher: name: QUBES Educational Resources
Year: 2023

description: This resources provides a framework for students to write a Microbiology Resource Announcement, collaboratively.
A new species of Pacifides from the Western Pacific Coast and the first fully freshwater species of the maricolan planarian genus Paucumara (Platyhelminthes, Tricladida, Maricola)
Creators: name: Li, Ming-Yi
name: Ma, Xin-Yi
name: Li, Wei-Xuan
name: Yang, Ying
name: Sluys, Ronald
name: Chen, Jia-Jia
name: Li, Shuang-Fei
name: Wang, An-Tai
Publisher: name: Taylor & Francis
Year: 2021
Subjects: subject: Genetics
subject: FOS: Biological sciences
subject: Molecular Biology
subject: Evolutionary Biology
subject: Ecology
subject: Developmental Biology
subject: Inorganic Chemistry
subject: FOS: Chemical sciences
subject: Infectious Diseases
subject: FOS: Health sciences
subject: Plant Biology
subject: Computational Biology

description: The present paper describes two new Chinese species of maricolan planarians through an integrated approach, including morphological, histological and molecular phylogenetic analyses. One new species forms the third species of the genus Pacifides and represents the first record of this genus from the Western Pacific. Further we document a third, new species of the genus Paucumara that is fully restricted to freshwater habitats, as it occurs on the shores of the Jialing River in Chongqing municipality far into the interior of China. Molecular phylogenetic analyses enabled us to determine, for the first time, the position of the genus Pacifides in the phylogenetic tree of the marine triclads. We also provide information on the feeding and reproduction of the new species of Pacifides. The paper concludes with two speculative scenarios on the evolutionary history that may have led to the present-day far inland occurrence and freshwater ecology of the new species of Paucumara; one scenario involves tectonic uplift-driven speciation and niche evolution, while the other invokes passive upstream dispersal via the Yangtze River. http://www.zoobank.org/urn:lsid:zoobank.org:act:43AE0799-EF9E-452F-99E5-AEE2271D3EA9 http://www.zoobank.org/urn:lsid:zoobank.org:act:79AD55BC-CAA1-4769-853E-7B11CC6ED1A7
Inclusive charged hadron elliptic flow in Au + Au collisions at $\sqrt{s_{NN}}$ = 7.7 - 39 GeV
Creators: name: STAR Collaboration
Publisher: name: arXiv
Year: 2012
Subjects: subject: Nuclear Experiment (nucl-ex)
subject: FOS: Physical sciences

description: A systematic study is presented for centrality, transverse momentum ($p_T$) and pseudorapidity ($η$) dependence of the inclusive charged hadron elliptic flow ($v_2$) at midrapidity($|η| < 1.0$) in Au+Au collisions at $\sqrt{s_{NN}}$ = 7.7, 11.5, 19.6, 27 and 39 GeV. The results obtained with different methods, including correlations with the event plane reconstructed in a region separated by a large pseudorapidity gap and 4-particle cumulants ($v_2{4}$), are presented in order to investigate non-flow correlations and $v_2$ fluctuations. We observe that the difference between $v_2{2}$ and $v_2{4}$ is smaller at the lower collision energies. Values of $v_2$, scaled by the initial coordinate space eccentricity, $v_{2}/\varepsilon$, as a function of $p_T$ are larger in more central collisions, suggesting stronger collective flow develops in more central collisions, similar to the results at higher collision energies. These results are compared to measurements at higher energies at the Relativistic Heavy Ion Collider ($\sqrt{s_{NN}}$ = 62.4 and 200 GeV) and at the Large Hadron Collider (Pb + Pb collisions at $\sqrt{s_{NN}}$ = 2.76 TeV). The $v_2(p_T)$ values for fixed $p_T$ rise with increasing collision energy within the $p_T$ range studied ($< 2 {\rm GeV}/c$). A comparison to viscous hydrodynamic simulations is made to potentially help understand the energy dependence of $v_{2}(p_{T})$. We also compare the $v_2$ results to UrQMD and AMPT transport model calculations, and physics implications on the dominance of partonic versus hadronic phases in the system created at Beam Energy Scan (BES) energies are discussed.
description: 20 pages, 12 figures. Version accepted by PRC
Epidemiological shifts and risk behaviours for oral and oropharyngeal cancers in multicultural population of British Columbia, Canada
Creators: name: Auluck, Ajit
Publisher: name: University of British Columbia
Year: 2012

description: Although smoking prevalence in British Columbia (BC) is decreasing, numbers of oral cancers are increasing. This change may reflect new emerging risk factors, including an increase in human papillomavirus (HPV) infections and greater immigration from high-risk countries. Currently, in BC there is no data on the trends in oral cancer incidence and survival by ethnicity or by etiologically clustered oral cancer subsites (oral cavity cancers, OCC, which are predominantly tobacco related; and oropharyngeal cancers, OPC, which are predominantly HPV-related). Oral cancers were retrieved from BC Cancer Registry (BCCR) from 1980 to 2006 and the following information collected: names, demographic, tumor, treatment and outcome information. When specific information was not complete, chart review was done. South Asian (SA) or Chinese ethnicities were determined by using previously generated ethnic surname list. Age-adjusted incidence rates (AAIR), age-specific incidence rates (ASIR) and 5-year survival rates for these three populations were calculated by sex, grouping the cancers into etiologically clustered subsites. Calculations were done for each year from 1980 to 2006. An ethnographic study was then conducted to describe the patterns of access, use and perceptions of SA men towards chewing tobacco-containing betel quid (BQ). Extensive field work included participant observations and semi-structured interviews. We have for the first time shown that the incidence of HPV-related OPC has surpassed that of tobacco-related OCC in men. For female, the incidence rates of OPC increased and OCC unchanged. AAIR for OCC was highest in SA males and females while rates of OPC were highest in general population males and Chinese males. Survival rates for OCC were unchanged and for OPC improved in males. SA had poorest survival rates for OCC. Ethnographic findings revealed that among SA males chewing tobacco-containing BQ was viewed as a culturally accepted practice. Availability of BQ, perceived benefits of chewing, ability to conceal the habit, and a lack of awareness of health risks also supported chewing practices. These findings provide a strong foundation for continued work in this field aimed at identifying effective prevention and treatment strategies for oral cancer.
Evaluation and Optimization of Weather Networks in Athabasca Oil Sands Region
Creators: name: Deshmukh, Dhananjay
Publisher: name: Schulich School of Engineering
Year: 2023
Subjects: subject: correlation analysis
subject: similarity analysis
subject: weather network optimization
subject: wind speed and direction
subject: rationalization
subject: Athabasca river basin
subject: weather
subject: redundancy
subject: climate
subject: Engineering
subject: Engineering--Environmental

description: The monitoring of weather is required for climate studies, research, and forecasting. For the monitoring purpose, three networks of 19 stations i.e., Water Quantity Program (WQP), Meteorological Towers (MT), and Edge Sites (ES) were operational in Athabasca oil sands region. The overall objective of the study was to identify similarities/redundancies in meteorological observations for the optimization of weather networks. For this, firstly similarity among meteorological parameters have been quantified for air temperature (AT), relative humidity (RH), solar radiation (SR), barometric pressure (BP), precipitation (PR), and snow depth (SD) among station-pairs of each network. In this process, Pearson’s correlation coefficient (r) and average absolute error (AAE) were the best representative measures from the methods of association and coincidence while proposed percentage of similarity (PS%) was the best in comparison to r and AAE to quantify the similarity. Further, RH found to be the least variable with strong and acceptable similarity in each network while similarity was decreased in order of SD, BP, AT, SR, and PR respectively. Secondly, Wind data has been analyzed for these three networks to find the optimal network. Here, it has been revealed that wind rose diagram only appropriate for visual comparison of wind characteristics while r, AAE and PS measures were suitable for similarity analysis of wind. Later, it has been found that all station from these three networks were required to represent wind variability in the region due to very low and unacceptable PS values. Thirdly, influence of land cover and topography have been evaluated on meteorological parameters of these 19 stations where they categorised under seven groups based on similar kind of land cover and topography. In this evaluation, parameters AT and SR were shown strong correlation but limited similarity while RH exhibit the least variability in each group. Moreover, BP and SD have some similarities while PR and WSD were highly variable due to various locational factors other than similar land cover and topography.
Measurements of high-n transitions in intermediate mass kaonic atoms by SIDDHARTA-2 at DA$\mathrmΦ$NE
Creators: name: Sgaramella, F.
name: Tüchler, M.
name: Amsler, C.
name: Bazzi, M.
name: Bosnar, D.
name: Bragadireanu, M.
name: Cargnelli, M.
name: Carminati, M.
name: Clozza, A.
name: Deda, G.
name: Del Grande, R.
name: De Paolis, L.
name: Fabbietti, L.
name: Fiorini, C.
name: Friščić, I.
name: Guaraldo, C.
name: Iliescu, M.
name: Iwasaki, M.
name: Khreptak, A.
name: Manti, S.
name: Marton, J.
name: Miliucci, M.
name: Moskal, P.
name: Napolitano, F.
name: Niedźwiecki, S.
name: Ohnishi, H.
name: Piscicchia, K.
name: Sada, Y.
name: Scordo, A.
name: Shi, H.
name: Silarski, M.
name: Sirghi, D.
name: Sirghi, F.
name: Skurzok, M.
name: Spallone, A.
name: Toho, K.
name: Doce, O. Vazquez
name: Widmann, E.
name: Yoshida, C.
name: Zmeskal, J.
name: Curceanu, C.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Nuclear Experiment (nucl-ex)
subject: Instrumentation and Detectors (physics.ins-det)
subject: FOS: Physical sciences

description: The SIDDHARTA-2 experiment installed at the DA$\mathrmΦ$NE collider of INFN-LNF performed, for the first time, measurements of high-n transitions in intermediate mass kaonic atoms during the data taking campaigns of 2021 and 2022. Kaonic carbon, oxygen, nitrogen and aluminium transitions, which occur in the setup materials, were measured by using the kaons stopped in the gaseous helium target cell with aluminium frames and Kapton walls, and are reported in this paper. These new kaonic atoms measurements add valuable input to the kaonic atoms transitions data base, which is used as a reference for theories and models of the low-energy strong interaction between antikaon and nuclei. Moreover, these results pave the way for future dedicated kaonic atoms measurements through the whole periodic table and to a new era for the antikaon-nuclei studies at low energy.
description: 8 pages, 7 figures
A variational formulation for constitutive laws described by bipotentials
Creators: name: Buliga, Marius
name: de Saxce, Gery
name: Vallee, Claude
Publisher: name: arXiv
Year: 2011
Subjects: subject: Functional Analysis (math.FA)
subject: FOS: Mathematics
subject: 74A20, 49J40 (Primary) 26B25 (Secondary)

description: Inspired by the algorithm of Berga and de Saxce for solving the discretisation in time of the evolution problem for an implicit standard material, we propose a general variational formulation in terms of bipotentials.
Spirits in the Gutters: The British Invasion and the Haunting of the Twentieth Century
Creators: name: Sewel, Tom
Publisher: name: Arts
Year: 2023
Subjects: subject: Comics
subject: Graphic Narrative
subject: Baroque
subject: Modernism
subject: Post-structuralism
subject: Otherness
subject: American Literature
subject: English Literature
subject: Literature

description: In this dissertation, I analyze the significant artistic and literary shifts initiated in mainstream US superhero comics by the British Invasion authors Alan Moore, Grant Morrison, Warren Ellis (among others), and argue that their restless curiosity in exploring how the comics page can come to make meaning is part of a tradition of literary production whose roots run back through the disruptive US/UK modernisms of the early twentieth century, the fragmented spiritual affects of Romanticism, and the dissonant overcomplications of Baroque art. I argue that that the impact of this group of writers instigated a sea change of generational proportions in the direction of American comics writing from the late 1980s to the early 2000s. This change began with an increased focus on textuality and the tropes of literary storytelling (such as unreliable narrators, non-linear narratives, and biting political allegory) but was always accompanied by and generative of an innovative and experimental approach to the mechanics of visual storytelling in terms of the manipulation of layouts, panelling, guttering, and other concrete elements of the comics page. US superhero comics written and illustrated by US creators published subsequent to the British Invasion and up to the present day, continue to reflect the deep shifts in aesthetic and literary preoccupations inaugurated by the authors of the British Invasion, with Moore, Morrison, and Ellis chief among them. At stake in this sea change is the figure of the unreconstructed, all-American superhero as a symbol of hope, justice, morality, and honour. I argue that the British Invasion authors brought a critical, intellectualized cynicism to their own superhero writing, which worked to create and sustain new audiences of more mature comics readers whose taste for overtly political or philosophical comics remains a powerful market force in the comics industry today. The Invasion writers changed the way that stories could be told in superhero comics, and while they may not have been successful in recouping the radical potential of the superhero as a figure of collective liberation, they heralded an enduring shift in the kinds of stories that mainstream comics were allowed to tell.
Additional file 3 of Gaps in research and capacity development for malaria surveillance and response in the Asia–Pacific: meeting report
Creators: name: Sirimatayanant, Massaya
name: Hein, Phone Si
name: Anderson, Laura Fay
name: Montoya, Lucía Fernández
name: Potter, Rebecca
name: Nghipumbwa, Mwalenga
name: Ranaweera, Prasad
name: Ngor, Pengby
name: Phetsouvanh, Rattanaxay
name: Maude, Richard J.
Publisher: name: figshare
Year: 2023
Subjects: subject: Medicine
subject: Molecular Biology
subject: Neuroscience
subject: Pharmacology
subject: Sociology
subject: FOS: Sociology
subject: Cancer
subject: Science Policy
subject: Infectious Diseases
subject: FOS: Health sciences

description: Additional file 3: Breakout groups and identified research priorities on malaria surveillance in the region.
An Assessment of Caribou (Rangifer tarandus) Genomic Diversity and Structure in Western Canada to Guide Species Conservation and Management
Creators: name: Michalak, Anita
Publisher: name: Veterinary Medicine
Year: 2023
Subjects: subject: conservation genomics
subject: population structure
subject: genetic differentiation
subject: clustering
subject: evolutionarily significant units
subject: ecotypes
subject: endangered wildlife
subject: Forestry and Wildlife
subject: Ecology
subject: FOS: Biological sciences
subject: Genetics
subject: Zoology

description: Human-induced environmental change is one of the biggest threats to global biological diversity, and the resulting environmental conditions have made it increasingly difficult for species to adapt and survive. The use of genomic technologies, such as the inference of genetic structure, can aid species conservation and prevent population declines. Particularly for caribou (Rangifer tarandus), which are considered an at-risk species across Canada, determining population genetic structure can help delineate units for conservation while detecting potentially cryptic population structure and diversity as well as undetected and/or mislabeled populations. For my M.Sc. thesis, I studied genomic diversity in caribou sampled throughout western Canada to better characterize population structure and supplement previous genetic studies conducted in this region. I accomplished this using several population structure inference methods and by combining individual-based genomic and spatial data for 658 individuals derived from 41 herds across British Columbia (BC) and Alberta (AB). Results indicate that population structure inferred from genomic data reflects neither past nor present caribou classification schemes. Instead, caribou genetic differentiation in BC and AB is best reflected at K=4 clusters, which primarily: (1) identifies a potential new conservation unit composed of individuals belonging to Itcha-Ilgachuz and neighboring subpopulations, and (2) redefines the boundaries of existing populations. Despite the need for multiple lines of evidence to provide complementary criteria for designating distinct units for conservation or populations, my work illustrates how genomics can help inform and improve the delineation of such conservation and management units for caribou.
Exploring the role of a facilitator in supporting family carers when embedding the iSupport for Dementia programme in care services: A qualitative study
Creators: name: Yu, Y
name: Hunter, SC
name: Xiao, L
name: Meyer, Claudia
name: Chapman, M
name: Tan, KP
name: Chen, L
name: Mckechnie, S
name: Ratcliffe, J
name: Ullah, S
name: Kitson, A
name: Andrade, AQ
name: Whitehead, C
Publisher: name: La Trobe
Year: 2023
Subjects: classificationCode: 4203
subject: Health services and systems
classificationCode: 4205
subject: Nursing
subject: FOS: Health sciences

description: Aims: To explore stakeholders' perceptions of a facilitator's role in supporting carers when embedding iSupport for Dementia psychoeducation program, in care services. Methods: A qualitative descriptive study design was applied. Data were collected from workshops and interviews with carers of people living with dementia (PLWD)and with health and social care professionals from two tertiary hospitals and two community aged care organisations across three Australian states between October 2021 and March 2022. A thematic analysis was used to analyse data. The COREQ guideline was followed to report our findings. Results: A total of 30 family carers and 45 health and social care professionals participated in the study. Three main themes and seven subthemes were identified from the data. We described the main themes as (1) the facilitator's role at the time of dementia diagnosis, (2) the facilitator's role throughout the everyday dementia care journey and (3) the facilitator's role during transition moments. Conclusions: Caring for family members with dementia is demanding and stressful for carers. Embedding a facilitator-enabled iSupport for Dementia program in hospital and community aged care settings has the potential to mitigate sources of stress associated with care recipient factors, carer factors and care service factors, and improve the health and well-being of carers and those for whom they care. Relevance to Clinical Practice: Our findings will inform the establishment of iSupport facilitators appointed by dementia care providers in hospital and community care settings and help determine their roles and responsibilities in delivering the iSupport program. Our findings relate to nurse-led and coordinated dementia care in hospital and community aged care settings. Patient or Public Contribution: This study was co-designed with stakeholders from two aged care organisations and two tertiary hospitals. The study participants were staff employed by these organisations and carers of PLWD who were service users.
Density preturbations in a finite scale factor singularity universe
Creators: name: Balcerzak, Adam
name: Denkiewicz, Tomasz
Publisher: name: arXiv
Year: 2012
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We discuss evolution of density perturbations in cosmological models which admit finite scale factor singularities. After solving the matter perturbations equations we find that there exists a set of the parameters which admit a finite scale factor singularity in future and instantaneously recover matter density evolution history which are indistinguishable from the standard LCDM scenario.
description: 4 pages
On general relativistic uniformly rotating white dwarfs
Creators: name: Boshkayev, Kuantay
name: Rueda, Jorge A.
name: Ruffini, Remo
name: Siutsou, Ivan
Publisher: name: arXiv
Year: 2012
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: The properties of uniformly rotating white dwarfs (RWDs) are analyzed within the framework of general relativity. Hartle's formalism is applied to construct the internal and external solutions to the Einstein equations. The WD matter is described by the relativistic Feynman-Metropolis-Teller equation of state which generalizes the Salpeter's one by taking into account the finite size of the nuclei, the Coulomb interactions as well as electroweak equilibrium in a self-consistent relativistic fashion. The mass $M$, radius $R$, angular momentum $J$, eccentricity $ε$, and quadrupole moment $Q$ of RWDs are calculated as a function of the central density $ρ_c$ and rotation angular velocity $Ω$. We construct the region of stability of RWDs ($J$-$M$ plane) taking into account the mass-shedding limit, inverse $β$-decay instability, and the boundary established by the turning-points of constant $J$ sequences which separates stable from secularly unstable configurations. We found the minimum rotation periods $\sim 0.3$, 0.5, 0.7 and 2.2 seconds and maximum masses $\sim 1.500$, 1.474, 1.467, 1.202 $M_\odot$ for $^{4}$He, $^{12}$C, $^{16}$O, and $^{56}$Fe WDs respectively. By using the turning-point method we found that RWDs can indeed be axisymmetrically unstable and we give the range of WD parameters where it occurs. We also construct constant rest-mass evolution tracks of RWDs at fixed chemical composition and show that, by loosing angular momentum, sub-Chandrasekhar RWDs (mass smaller than maximum static one) can experience both spin-up and spin-down epochs depending on their initial mass and rotation period while, super-Chandrasekhar RWDs (mass larger than maximum static one), only spin-up.
description: The Astrophysical Journal; in press
Nonlinear Instability in a Semiclassical Problem
Creators: name: Galkowski, Jeffrey
Publisher: name: arXiv
Year: 2011
Subjects: subject: Analysis of PDEs (math.AP)
subject: FOS: Mathematics

description: We consider a nonlinear evolution problem with an asymptotic parameter and construct examples in which the linearized operator has spectrum uniformly bounded away from Re z >= 0 (that is, the problem is spectrally stable), yet the nonlinear evolution blows up in short times for arbitrarily small initial data. We interpret the results in terms of semiclassical pseudospectrum of the linearized operator: despite having the spectrum in Re z < -c < 0, the resolvent of the linearized operator grows very quickly in parts of the region Re z > 0. We also illustrate the results numerically.
Learning Symbolic Representations Through Joint GEnerative and DIscriminative Training
Creators: name: Sansone, Emanuele
name: Manhaeve, Robin
Publisher: name: arXiv
Year: 2023
Subjects: subject: Machine Learning (cs.LG)
subject: Artificial Intelligence (cs.AI)
subject: FOS: Computer and information sciences

description: We introduce GEDI, a Bayesian framework that combines existing self-supervised learning objectives with likelihood-based generative models. This framework leverages the benefits of both GEnerative and DIscriminative approaches, resulting in improved symbolic representations over standalone solutions. Additionally, GEDI can be easily integrated and trained jointly with existing neuro-symbolic frameworks without the need for additional supervision or costly pre-training steps. We demonstrate through experiments on real-world data, including SVHN, CIFAR10, and CIFAR100, that GEDI outperforms existing self-supervised learning strategies in terms of clustering performance by a significant margin. The symbolic component further allows it to leverage knowledge in the form of logical constraints to improve performance in the small data regime.
description: ICLR 2023 Workshop NeSy-GeMs. arXiv admin note: substantial text overlap with arXiv:2212.13425
Corner flow advancement in porous media
Creators: name: Ghoreishi, Seyyed Ali
Publisher: name: Schulich School of Engineering
Year: 2023
Subjects: subject: Engineering
subject: Engineering--Chemical

description: Preferential wetting of solids by one fluid can induce capillary driven flows in two phase fluid systems. The existence of geometrical inhomogeneities in the form of surface roughness can increase the curvature of the interface, hence, it may strengthen the capillary driven flow at the corners. Corner flow can play a significant role in many processes the involve two phase flow in porous media such as enhanced oil production from or gas storage in underground reservoir rocks. This dissertation addresses some of the issues related to the corner flow in porous media primarily from an experimental point of view. First, the existence of corner flow is stablished in systems where water (the wetting phase) is injected into the micromodel that is initially saturated with mineral oil. Before water reaches to the outlet port of micromodel, i.e. the breakthrough of water, the viscous forces are dominant in advancing the two-phase front. The images of experiments reveals the propagation of water ahead of the finger. However, the water propagation, driven by corner flow, continues until the capillary forces is balanced out by the resistance to move the viscous oil. In the second part of the thesis, the effect of corner flow on the heavy oil displacement experiments by water and a surfactant solution is studied. The experiments show that, in surfactant flooding systems, the corner flow contributes in the post-breakthrough heavy oil production by spreading of surfactants ahead of the water finger boundaries, hence, promoting the oil in water emulsification. Consequently, the emulsified oil droplets are mobilized and produced by the main water stream. Finally, the impact of corner flow on the gas (hydrogen) storage capacity of a water filled pore-network model is established. During the imbibition process, the corner flow leads to the trapping of significant volumes of hydrogen in larger pores. It is revealed that the gas storage increases by salinity in the designed pore-network model primarily as a result of a decrease in the volume of residual water fingers at higher salinities. Consequently, all salinities have a similar storage capacity, despite the differences during the drainage and imbibition processes.
Experimental and materials considerations for the topological superconducting state in electron and hole doped semiconductors: searching for non-Abelian Majorana modes in 1D nanowires and 2D heterostructures
Creators: name: Sau, Jay D.
name: Tewari, Sumanta
name: Sarma, S. Das
Publisher: name: arXiv
Year: 2011
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: In proximity to an s-wave superconductor, a one- or two-dimensional, electron- or hole-doped semiconductor with a sizable spin-orbit coupling and a Zeeman splitting can support a topological superconducting (TS) state. The semiconductor TS state has Majorana fermions as localized zero-energy excitations at order parameter defects such as vortices and sample edges. Here we examine the effects of quenched disorder from the semiconductor surface on the stability of the TS state in both electron- and hole-doped semiconductors. By considering the interplay of broken time reversal symmetry (due to Zeeman splitting) and disorder we derive an expression for the disorder suppression of the superconducting quasiparticle gap in the TS state. We conclude that the effects of disorder can be minimized by increasing the ratio of the spin-orbit energy with the Zeeman splitting. By giving explicit numbers we show that a stable TS state is possible in both electron- and hole-doped semiconductors for experimentally realistic values of parameters. We discuss possible suitable semiconductor materials which should be the leading candidates for the Majorana search in solid state systems.
description: 11 pages, 2 figures: v3 published version
Phoretic Phenomena of Colloidal Particles in a Dead-end Pore Microfluidic Channel
Creators: name: Nooryani, Matina
Publisher: name: Schulich School of Engineering
Year: 2023
Subjects: subject: Microfluidics
subject: Phoretic phenomena
subject: Colloidal particles
subject: porous particles
subject: Fluid mechanics
subject: Engineering
subject: Engineering--Chemical

description: Colloidal particles can be manipulated under the gradient of an external field to transport them in the system toward desired locations. The motion of colloidal particles resulting from an imposed or self-generated concentration gradient is called diffusiophoresis which has been used in a wide range of applications such as drug delivery, wastewater treatment, and enhanced oil recovery. This phenomenon provides a low-cost and easy portable method to manipulate particles. Previous works investigated the diffusiophoretic motion of non-porous particles in microfluidic channels both experimentally and theoretically. However, the migration of porous particles under the effect of concentration gradient has not been studied experimentally. In this work, we have used a dead-end pore microfluidic channel to explore the diffusiophoretic motion of porous particles. For this purpose, we first study the migration of non-porous particles in the dead-end pore channel with and without the presence of background concentration gradients. Our results indicate a temporary self-generated concentration gradient is generated in the channel resulting from the interfacial interaction of PDMS walls with the ions present in DI water without introducing any background concentration gradient. In the presence of an electrolyte concentration gradient, the relative difference in the ions' diffusivity (β) and particles’ zeta potential are two main effective factors on the diffusiophoretic motion of non-porous particles. In the next section, we study the diffusiophoretic motion of porous particles, and differences in the case of non-porous particles are investigated. In contrast to non-porous particles, porous particles’ migration under the influence of concentration gradient is a function of pore size, surface area, and surface charge density. The surface charge density of porous particles can change significantly because of counterions diffusion into the porous particles which can result in inversion of motion direction. Therefore, the effect of the interior microstructure of colloidal particles is crucial in controlling their diffusiophoretic motion.
Novel stand-off pads for ultrasound-CT registration and elastography
Creators: name: Kingma, Raoul Jacob
Publisher: name: University of British Columbia
Year: 2012

description: Laparoscopic surgery has many advantages including reduced patient mor- bidity and improved recovery times, but has the drawback of a very limited eld of view. Thus improvements in image guidance in laparoscopic surgery are highly desirable, especially in highly technical operations such as robot- ically assisted laparoscopic partial nephrectomies (RALPN). In RALPN, image guidance can be enhanced by bringing pre-operative computed tomography (CT) and intra-operative ultrasound images into the surgeon's eld of view, depicting underlying anatomy. Multiple tracking and registration steps with inherent trade-o s of accuracy and convenience are normally required to display the images in the camera view. In this thesis, a new tracker-less method is developed for the step of registering pre-operative 3D CT to pre-operative 3D ultrasound which uses a novel ducial stand-o pad. The pad contains ducial markers visible in both modalities which are matched to obtain the registration parameters. The ducial stand-o pad is tested in a controlled phantom study to determine registration accuracy and in a small clinical study to determine clinical feasibility. The ducial stand- o pad is capable of similar registration accuracies to incumbent approaches without the need for external tracking equipment, and is easily integrated into medical imaging protocols. A second enhancement of RALPN image guidance is the integration of ultrasound elastography to display mechanical properties of the tissue. Elas- tography has been in development for over two decades, but further improve- ments are required to improve quantitative estimations of tissue properties. In this thesis, a stand-o pad is used as a method of measuring ultrasound transducer contact force distributions, which will allow force measurements to be used in solving for local tissue elasticities. Forces are obtained by measuring displacements in the stand-o pad and converting them to forces using a nite element model. The accuracy of displacement estimates is tested, and the force computation process is validated. As well, a force measurement system is implemented for use with a three-dimensional linear array transducer. The results show that this is a feasible force measurement method, providing approximately 10% error in force measurements.
Field dependent nilpotent symmetry for gauge theories
Creators: name: Upadhyay, Sudhaker
name: Mandal, Bhabani Prasad
Publisher: name: arXiv
Year: 2012
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We construct the field dependent mixed BRST (combination of BRST and anti-BRST) transformations for pure gauge theories. These are shown to be an exact nilpotent symmetry of both the effective action as well as the generating functional for certain choices of the field dependent parameters. We show that the Jacobian contributions for path integral measure in the definition of generating functional arising from BRST and anti-BRST part compensate each other. The field dependent mixed BRST transformations are also considered in field/antifield formulation to show that the solutions of quantum master equation remain invariant under these. Our results are supported by several explicit examples.
description: 25 pages, No figures, Revtex
Supplementary document for The synergistic luminescence effect and high-pressure optical properties of CsPbBr2Cl@EuMOFs nanocomposites - 6436959.pdf
Creators: name: li, mingxing
name: liu, wenting
name: Yang, Tieshan
name: Xu, Qinfeng
name: mu, haifeng
name: han, jing
name: Cao, KunJian
name: tan, xiaoming
name: Wang, Kai
name: Yang, Chuanlu
Publisher: name: Optica Publishing Group
Year: 2023
Subjects: Uncategorized

description: Supplemental Materials
A Multi-Purpose Continuum Robot for Minimally Invasive Surgery
Creators: name: Esfandiari, Mojtaba
Publisher: name: Schulich School of Engineering
Year: 2023
Subjects: subject: Medical Robotics
subject: Continuum Robots
subject: Model Predictive Control
subject: Engineering--Biomedical
subject: Engineering--Mechanical
subject: Robotics

description: This thesis is about ''A Multi-Purpose Continuum Robot for Minimally Invasive surgery'' which consists of five chapters. It starts with an Introduction and Literature Review that studies some of the most famous surgical robotic systems and analyses their pros and cons. Chapter two has to do with the problem statement and challenges that need to be addressed while designing our specific surgical tool, and a CAD design of a flexible continuum robot will be done for our brain surgery application. In chapter three, the kinematic modeling of the proposed robot is analyzed by a new model based on the Euler spirals and the results are compared with conventional constant curvature models. In chapter four, a model predictive control algorithm is proposed that considers the input saturation constraints on robot actuators. Finally, a discussion and conclusion will be provided in chapter five.
A witness for coherent electronic oscillations in ultrafast spectroscopy
Creators: name: Yuen-Zhou, Joel
name: Krich, Jacob J.
name: Aspuru-Guzik, Alán
Publisher: name: arXiv
Year: 2012
Subjects: subject: Quantum Physics (quant-ph)
subject: Chemical Physics (physics.chem-ph)
subject: FOS: Physical sciences

description: We report a conceptually straightforward witness that isolates coherent electronic oscillations from their vibronic counterparts in nonlinear optical spectra of molecular aggregates: Coherent oscillations as a function of waiting time in broadband pump/broadband probe spectra correspond to coherent electronic oscillations. Oscillations in individual peaks of 2D electronic spectra do not necessarily yield this conclusion. Our witness is simpler to implement than quantum process tomography and potentially resolves a long-standing controversy on the character of oscillations in ultrafast spectra of photosynthetic light harvesting systems.
description: 4 pages, 2 figures, plus Supplementary Information. Work presented by the first author on March 1, 2012 at APS, Boston, Session W41, Focus Session on Quantum Coherence in Biological Systems
Video analysis of the damped oscillations of Pohl's pendulum
Creators: name: Stefanov, Ivan Z.
name: Denev, Nikolay
name: Donkov, Sava
Publisher: name: arXiv
Year: 2023
Subjects: subject: Physics Education (physics.ed-ph)
subject: Data Analysis, Statistics and Probability (physics.data-an)
subject: FOS: Physical sciences

description: In this paper problems that arose with the introduction of distance learning in physics at the Technical University of Sofia due to the COVID-19 pandemic and the imposition of video recording of laboratory exercises are indicated. It was found that the video for the ''Damped Mechanical Oscillations'' exercise provides enough information for a more detailed and in-depth analysis of the studied phenomenon compared to the standard way of capturing the data. The Video Editor program was used to view the video frame by frame and statistical processing - non-linear regression - was performed with the recorded data. The laboratory results are compared with the theoretical function, the parameters of which are optimized as a result of the specified processing. A theoretical model of the damped oscillation is described and the dependence of the damping coefficient on the current through the electromagnetic brake is theoretically investigated.
description: 10 pages, link to the pubished version: https://rrp.nipne.ro/2022/AN74909.pdf
Controllable exchange coupling between two singlet-triplet qubits
Creators: name: Li, Rui
name: Hu, Xuedong
name: You, J. Q.
Publisher: name: arXiv
Year: 2012
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We study controllable exchange coupling between two singlet-triplet qubits. We start from the original second quantized Hamiltonian of a quadruple quantum dot system and obtain the effective spin-spin interaction between the two qubits using the projection operator method. Under a strong uniform external magnetic field and an inhomogeneous local micro-magnetic field, the effective interqubit coupling is of the Ising type, and the coupling strength can be expressed in terms of quantum dot parameters. Finally, we discuss how to generate various two-qubit operations using this controllable coupling, such as entanglement generation, and controlled-NOT gate.
description: 9 pages, 3 figures
Modeling Flocks and Prices: Jumping Particles with an Attractive Interaction
Creators: name: Balazs, Marton
name: Racz, Miklos Z.
name: Toth, Balint
Publisher: name: arXiv
Year: 2011
Subjects: subject: Probability (math.PR)
subject: FOS: Mathematics
subject: 60K35 (Primary), 60J75 (Secondary)

description: We introduce and investigate a new model of a finite number of particles jumping forward on the real line. The jump lengths are independent of everything, but the jump rate of each particle depends on the relative position of the particle compared to the center of mass of the system. The rates are higher for those left behind, and lower for those ahead of the center of mass, providing an attractive interaction keeping the particles together. We prove that in the fluid limit, as the number of particles goes to infinity, the evolution of the system is described by a mean field equation that exhibits traveling wave solutions. A connection to extreme value statistics is also provided.
description: 35 pages, 9 figures. A shortened version appears as arXiv:1108.2436