cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
title: Mechanistic insight into bunyavirus-induced membrane fusion from structure-function analyses of the hantavirus envelope glycoprotein Gc
Creators: name: Guardado-Calvo, Pablo
name: Bignon, Eduardo A.
name: Stettner, Eva
name: Jeffers, Scott Allen
name: Pérez-Vargas, Jimena
name: Pehau-Arnaudet, Gerard
name: Tortorici, M. Alejandra
name: Jestin, Jean- Luc
name: England, Patrick
name: Tischler, Nicole D.
name: Rey, Félix A.
Publisher: name: Universität Potsdam
Year: 2019

description: Hantaviruses are zoonotic viruses transmitted to humans by persistently infected rodents, giving rise to serious outbreaks of hemorrhagic fever with renal syndrome (HFRS) or of hantavirus pulmonary syndrome (HPS), depending on the virus, which are associated with high case fatality rates. There is only limited knowledge about the organization of the viral particles and in particular, about the hantavirus membrane fusion glycoprotein Gc, the function of which is essential for virus entry. We describe here the X-ray structures of Gc from Hantaan virus, the type species hantavirus and responsible for HFRS, both in its neutral pH, monomeric pre-fusion conformation, and in its acidic pH, trimeric post-fusion form. The structures confirm the prediction that Gc is a class II fusion protein, containing the characteristic beta-sheet rich domains termed I, II and III as initially identified in the fusion proteins of arboviruses such as alpha-and flaviviruses. The structures also show a number of features of Gc that are distinct from arbovirus class II proteins. In particular, hantavirus Gc inserts residues from three different loops into the target membrane to drive fusion, as confirmed functionally by structure-guided mutagenesis on the HPS-inducing Andes virus, instead of having a single "fusion loop". We further show that the membrane interacting region of Gc becomes structured only at acidic pH via a set of polar and electrostatic interactions. Furthermore, the structure reveals that hantavirus Gc has an additional N-terminal "tail" that is crucial in stabilizing the post-fusion trimer, accompanying the swapping of domain III in the quaternary arrangement of the trimer as compared to the standard class II fusion proteins. The mechanistic understandings derived from these data are likely to provide a unique handle for devising treatments against these human pathogens.
description: Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe, 676
GGHead: Fast and Generalizable 3D Gaussian Heads
Creators: name: Kirschstein, Tobias
name: Giebenhain, Simon
name: Tang, Jiapeng
name: Georgopoulos, Markos
name: Nießner, Matthias
Publisher: name: arXiv
Year: 2024
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: FOS: Computer and information sciences

description: Learning 3D head priors from large 2D image collections is an important step towards high-quality 3D-aware human modeling. A core requirement is an efficient architecture that scales well to large-scale datasets and large image resolutions. Unfortunately, existing 3D GANs struggle to scale to generate samples at high resolutions due to their relatively slow train and render speeds, and typically have to rely on 2D superresolution networks at the expense of global 3D consistency. To address these challenges, we propose Generative Gaussian Heads (GGHead), which adopts the recent 3D Gaussian Splatting representation within a 3D GAN framework. To generate a 3D representation, we employ a powerful 2D CNN generator to predict Gaussian attributes in the UV space of a template head mesh. This way, GGHead exploits the regularity of the template's UV layout, substantially facilitating the challenging task of predicting an unstructured set of 3D Gaussians. We further improve the geometric fidelity of the generated 3D representations with a novel total variation loss on rendered UV coordinates. Intuitively, this regularization encourages that neighboring rendered pixels should stem from neighboring Gaussians in the template's UV space. Taken together, our pipeline can efficiently generate 3D heads trained only from single-view 2D image observations. Our proposed framework matches the quality of existing 3D head GANs on FFHQ while being both substantially faster and fully 3D consistent. As a result, we demonstrate real-time generation and rendering of high-quality 3D-consistent heads at $1024^2$ resolution for the first time. Project Website: https://tobias-kirschstein.github.io/gghead
description: Project Page: https://tobias-kirschstein.github.io/gghead/ ; YouTube Video: https://youtu.be/M5vq3DoZ7RI
Using the X-ray Dust Scattering Halo of Cygnus X-1 to determine distance and dust distributions
Creators: name: Xiang, Jingen
name: Lee, Julia C.
name: Nowak, Michael A.
name: Wilms, Jörn
Publisher: name: arXiv
Year: 2011
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: We present a detailed study of the X-ray dust scattering halo of the black hole candidate \cygx1 based on two \chandra\ HETGS observations. Using 18 different dust models, including one modified by us (dubbed XLNW), we probe the interstellar medium between us and this source. A consistent description of the cloud properties along the line of sight that describes at the same time the halo radial profile, the halo lightcurves, and the column density from source spectroscopy is best achieved with a small subset of these models. Combining the studies of the halo radial profile and the halo lightcurves, we favor a geometric distance to \cygx1 of $d=1.81\pm{0.09}$\,kpc. Our study also shows that there is a dense cloud, which contributes $\sim$50% of the dust grains along the line of sight to \cygx1, located at $\sim1.6$ kpc from us. The remainder of the dust along the line of sight is close to the black hole binary.
description: Accepted for publication in the Astrophysical Journal; 10 pages; 10 figures; 3 tables; emulateapj style
Investigating the morphology and CO gas kinematics of Sh2-112 region
Creators: name: Mallick, Kshitiz
name: Sharma, Saurabh
name: Dewangan, Lokesh
name: Ojha, Devendra
name: Panwar, Neelam
name: Baug, Tapas
Publisher: name: arXiv
Year: 2023
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: We present a study of the molecular cloud in Sh2-112 massive star forming region using the 3-2 transition of CO isotopologues - CO, 13CO, and C18O; supplemented in part by CGPS HI line emission and MSX data. Sh2-112 is an optically visible region powered by an O8V type massive star BD +45 3216, and hosts two Red MSX Survey sources - G083.7962+03.3058 and G083.7071+03.2817 - classified as HII region and young stellar object, respectively. Reduced spectral data products from the James Clerk Maxwell Telescope archive, centered on the two RMS objects with ~7'x7' field of view each, were utilised for the purpose. The 13CO(3-2) channel map of the region shows the molecular cloud to have filamentary extensions directed away from the massive star, which also seems to be at the edge of a cavity like structure. Multiple molecular cloud protrusions into this cavity structure host local peaks of emission. The integrated emission map of the region constructed from only those emission clumps detected above 5$σ$ level in the position-position-velocity space affirms the same. MSX sources were found distributed along the cavity boundary where the gas has the been compressed. Spectral extraction at these positions yielded high Mach numbers and low ratios of thermal to non-thermal pressure, suggesting a dominance of supersonic and non-thermal motion in the cloud.
description: 15 Pages, 11 Figures, Accepted in Journal of Astrophysics and Astronomy (JAA)
Transitions in the Web of Heterotic Vacua
Creators: name: Anderson, Lara B.
name: Gray, James
name: Ovrut, Burt
Publisher: name: arXiv
Year: 2010
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We analyze transitions between heterotic vacua with distinct gauge bundles using two complementary methods - the effective four-dimensional field theory and the corresponding geometry. From the viewpoint of effective field theory, such transitions occur between flat directions of the potential energy associated with heterotic stability walls. Geometrically, this branch structure corresponds to smooth deformations of the gauge bundle coupled to the chamber structure of Kähler moduli space. We demonstrate how such transitions can change important properties of the effective theory, including the gauge symmetry and the massless spectrum. Geometrically, this study is divided into deformations of the vector bundle which preserve the rank of the gauge bundle and those which change the rank. In the latter case, our results provide explicit solutions to a class of Li-Yau type deformation problems. Finally, we use the framework of stability walls and their effective theory to study Donaldson-Thomas invariants on Calabi-Yau threefolds.
description: 53 pages, 3 figures
Disruption of selective autophagy in coxsackievirus B3 infection
Creators: name: Shi, Junyan
Publisher: name: University of British Columbia
Year: 2015

description: Coxsackievirus infection induces an abnormal accumulation of ubiquitin aggregates that are generally believed to be harmful to the cells and play a key role in the pathogenesis of coxsackievirus-induced myocarditis and dilated cardiomyopathy. Selective autophagy mediated by autophagy adaptor proteins, including sequestosome 1 (SQSTM1/p62) and neighbor of BRCA1 gene 1 protein (NBR1), is an important pathway for disposing of misfolded proteins and damaged organelles. We demonstrated that SQSTM1 was cleaved following CVB3 infection through the proteolytic activity of viral proteinase 2Apro. The resulting cleavage fragments of SQSTM1 were no longer the substrates of autophagy, and their ability to form protein aggregates was greatly decreased due to incapability of interaction with ubiquitinated proteins. We further tested whether NBR1, a functional homolog of SQSTM1, can compensate for SQSTM1 loss-of-function after viral infection. Of interest, we found that NBR1 was also cleaved after coxsackievirus infection, excluding the possible compensation of NBR1 for the loss of SQSTM1. This cleavage took place at two sites mediated by virus-encoded proteinase 2Apro and 3Cpro, respectively. In addition to the loss-of-function, we showed that the C-terminal fragments of SQSTM1 and NBR1 exhibited a dominant-negative effect against native SQSTM1/NBR1, probably by competing for LC3 and ubiquitin chain binding. Apart from the disruption of selective autophagy, CVB3 infection also impaired autophagic flux as confirmed by flux assays with a combination of a tandem fluorescence-tagged LC3 stable cell line and a non-cleavable construct of SQSTM1. Finally, we studied the roles of SQSTM1 and NBR1 in autophagic degradation of depolarized mitochondria (referred to as mitophagy). Following mitochondrial depolarization induced by carbonyl cyanide m-chlorophenylhydrazone (CCCP), a mitochondrial uncoupler to trigger mitophagy, we demonstrated that NBR1 did not appear to be required for mitochondrial clustering. Deficiency of NBR1 alone or in concert with SQSTM1 did not block the clearance of damaged mitochondria, suggesting that NBR1 is dispensable for mitophagy regardless of the status of SQSTM1. Taken together, the findings in this study suggest novel mechanisms in coxsackieviral pathogenesis: coxsackievirus infection induces abnormal accumulation of ubiquitin conjugates through the disruption of selective degradation of protein aggregates and blockage of autophagic flux.
Max-Min Diversification with Fairness Constraints: Exact and Approximation Algorithms
Creators: name: Wang, Yanhao
name: Mathioudakis, Michael
name: Li, Jia
name: Fabbri, Francesco
Publisher: name: arXiv
Year: 2023
Subjects: subject: Data Structures and Algorithms (cs.DS)
subject: Computers and Society (cs.CY)
subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: Diversity maximization aims to select a diverse and representative subset of items from a large dataset. It is a fundamental optimization task that finds applications in data summarization, feature selection, web search, recommender systems, and elsewhere. However, in a setting where data items are associated with different groups according to sensitive attributes like sex or race, it is possible that algorithmic solutions for this task, if left unchecked, will under- or over-represent some of the groups. Therefore, we are motivated to address the problem of \emph{max-min diversification with fairness constraints}, aiming to select $k$ items to maximize the minimum distance between any pair of selected items while ensuring that the number of items selected from each group falls within predefined lower and upper bounds. In this work, we propose an exact algorithm based on integer linear programming that is suitable for small datasets as well as a $\frac{1-\varepsilon}{5}$-approximation algorithm for any $\varepsilon \in (0, 1)$ that scales to large datasets. Extensive experiments on real-world datasets demonstrate the superior performance of our proposed algorithms over existing ones.
description: 13 pages, 8 figures, to appear in SDM '23
Neutrino quantum kinetics in a core-collapse supernova
Creators: name: Shalgar, Shashank
name: Tamborra, Irene
Publisher: name: arXiv
Year: 2024
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: Our understanding of neutrino flavor conversion in the supernova core is still preliminary, despite its likely relevance to the neutrino-driven supernova mechanism. We present multi-angle and multi-energy numerical simulations of neutrino quantum kinetics within a spherically symmetric shell in the proximity of the region of neutrino decoupling. We rely on inputs from a one-dimensional core-collapse supernova model with a mass of $18.6\ M_\odot$ and find that, at early post-bounce times ($t_{\mathrm pb} \lesssim 0.5$~s), no crossing is present in the angular distribution of the electron neutrino lepton number and flavor conversion is triggered by slow collective instabilities. Angular crossings appear for $t_{\textrm{pb}} \gtrsim 0.5$~s and fast flavor conversion leads to flavor equipartition, with the spectral energy distribution of $ν_{e}$ ($\barν_{e}$) and $ν_{x}$ ($\barν_{x}$) becoming comparable. Notably, flavor equipartition is not a generic outcome of fast flavor conversion, rather it is a consequence of the relatively similar properties of neutrinos of different flavors characterizing the late accretion phase. Artificially tweaking the collision term to introduce an electron lepton number angular crossing for $t_{\mathrm{pb}} \lesssim 0.05$~s, we observe that flavor equipartition is not achieved. While our findings are restricted to a specific supernova model, and they only take into account the feedback of the neutrino background on the flavor conversion, they suggest a rich phenomenology in the supernova core as a function of the post-bounce time which needs to be further explored to assess its impact on the explosion mechanism.
description: 25 pages, 13 figures. Version accepted in JCAP
title: The germination niches of grassland species targeted for restoration
title: effects of seed pre-treatments
titleType: Subtitle
Creators: name: Wagner, Markus
name: Pywell, Richard F.
name: Knopp, Tatjana
name: Bullock, James M.
name: Heard, Matthew S.
Publisher: name: Universität Potsdam
Year: 2019

description: Restoration of semi-natural grassland communities
involves a combination of (1) sward disturbance to
create a temporal window for establishment, and (2)
target species introduction, the latter usually by seed
sowing. With great regularity, particular species
establish only poorly. More reliable establishment
could improve outcome of restoration projects and
increase cost-effectiveness. We investigated the
abiotic germination niche of ten poorly establishing
calcareous grassland species by simultaneously
exploring the effects of moisture and light availability
and temperature fluctuation on percentage germina-
tion and speed of germination. We also investigated
the effects of three different pre-treatments used to
enhance seed germination – cold-stratification, osmo-
tic priming and priming in combination with gibberellic
acid (GA 3 ) – and how these affected abiotic
germination niches. Species varied markedly in width
of abiotic germination niche, ranging from Carex flacca
with very strict abiotic requirements, to several species
reliably germinating across the whole range of abiotic
conditions. Our results suggest pronounced differ-
ences between species in gap requirements for
establishment. Germination was improved in most
species by at least one pre-treatment. Evidence for
positive effects of adding GA 3 to seed priming
solutions was limited. In several species, pre-treated
seeds germinated under a wider range of abiotic
conditions than untreated seeds. Improved knowledge
of species-specific germination niches and the effects
of seed pre-treatments may help to improve species
establishment by sowing, and to identify species for
which sowing at a later stage of restoration or
introduction as small plants may represent a more
viable strategy.
description: Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe, 675
Efficient full frequency GW for metals using a multipole approach for the dielectric screening
Creators: name: Leon, Dario A.
name: Ferretti, Andrea
name: Varsano, Daniele
name: Molinari, Elisa
name: Cardoso, Claudia
Publisher: name: arXiv
Year: 2023
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: The properties of metallic systems with important and structured excitations at low energies, such as Cu, are challenging to describe with simple models like the plasmon pole approximation (PPA), and more accurate and sometimes prohibitive full frequency approaches are usually required. In this paper we propose a numerical approach to $GW$ calculations on metals that takes into account the frequency dependence of the screening via the multipole approximation (MPA), an accurate and efficient alternative to current full-frequency methods that was recently developed and validated for semiconductors and overcomes several limitations of PPA. We now demonstrate that MPA can be successfully extended to metallic systems by optimizing the frequency sampling for this class of materials and introducing a simple method to include the $\mathbf{q}\to 0$ limit of the intra-band contributions. The good agreement between MPA and full frequency results for the calculations of quasi-particle energies, polarizability, self-energy and spectral functions in different metallic systems confirms the accuracy and computational efficiency of the method. Finally, we discuss the physical interpretation of the MPA poles through a comparison with experimental electron energy loss spectra for Cu.
description: 21 pages
An International Review of the Contributions of School-based Physical Activity, Physical Education, and School Sport to the Promotion of Health-enhancing Physical Activity
Creators: name: Bailey, Richard
name: Vašíčková, Jana
name: Vlček, Petr
name: Raya Demidoff, Andreu
name: Pühse, Uwe
name: Heck, Sandra
name: Scheuer, Claude
Publisher: name: Zenodo
Year: 2022
Subjects: active schools
physical activity
physical education
school sport
literature review

description: This report presents a series of reviews of the scientific literature to summarise the current evidence of the contributions of different school-based settings on the promotion of health-enhancing physical activity. The objectives of this report are: to review evidence from the last ten years of the contributions of school-based physical activity, physical education, and school sport on the promotion of health-enhancing physical activity; to consider the role of certain transversal factors in supporting the promotion of health-enhancing physical activity; to present a series of practical, evidence-based recommendations in support of the subsequent activities in the HEPAS project. The settings are: Physical activity (including Active Breaks; Active Learning; Active Recess; Active Transport; Active Homework); Physical Education (Curriculum physical education Lessons; Teacher Education / Workforce); and School Sport. The settings are supplemented by a set of ‘transversal categories’, which represent mediating factors for effective realisation of the promotion of health-enhancing physical activity are: Inclusion and Diversity; Continuous Professional Development; Facilities, Equipment and Resources; Community Partnerships; and School Events, Project Weeks, Camps.
description: Project: Healthy and Physically Active Schools in Europe Project Coordinator: Claude Scheuer Funder: European Commission Programme: Erasmus+ Key Action 2: Strategic Partnerships for School Education – 2019 Reference: 2019-1-LU01-KA201-050112 Timeline: December 2019 – November 2021 Project Sheet: https://ec.europa.eu/programmes/erasmus-plus/projects/eplus-project-details/#project/ 2019-1-LU01-KA201-050112 For further information on the HEPAS Project please follow the link: Website: https://www.movingschoolsaward.com/hepas/
Casimir-Polder interaction between a polarizable particle and a plate with a hole
Creators: name: Eberlein, Claudia
name: Zietal, Robert
Publisher: name: arXiv
Year: 2011
Subjects: subject: Atomic Physics (physics.atom-ph)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We determine exactly the non-retarded Casimir-Polder interaction between a neutral but polarizable particle and a perfectly reflecting sheet containing a circular hole. The calculation reveals a strong dependence of the interaction on the orientation of the particle's electric dipole moment with respect to the surface. For a dipole moment that is polarized perpendicularly to the surface the interaction potential has two saddle points lying above and below the plane of the surface, on a line through the centre of the aperture. For a dipole moment that is polarized parallel to the surface there is only one saddle point right in the middle of the aperture. Provided the particles' motion could be confined to a line through the middle of the aperture, this effect could potentially be used for population-sensitive trapping of particles.
description: 4 pages, 5 figures
Engagement with Chinese popular culture in adult Mandarin language learning and socialization
Creators: name: Fang, Sumin
Publisher: name: University of British Columbia
Year: 2015

description: Many studies in second language acquisition (SLA) have found that the incorporation of popular culture into classroom or self-learning can boost language learners’ motivation. However, little attention has been paid to Chinese as an Additional Language (CAL) learners’ usage of Chinese popular culture to learn Mandarin. This thesis seeks to explore how Chinese popular culture impacts CAL learners’ motivation for learning Mandarin and their language socialization process during their engagement. By creating a new theoretical framework which is a combination of language socialization and entertainment psychology, this study employs qualitative case study methods to investigate ten adult CAL learners’ experiences. Each participant was interviewed individually twice, before and after their two-week engagement with Chinese popular culture. Additionally, they were required to note down their pop culture activities and reflections during this period. This research found Chinese popular culture complemented learners’ formal classroom-based learning and contributed to arousing and/or sustaining their motivation to learn Mandarin. In addition, CAL learners used semiotic resources in Chinese popular culture to construct their identities in three dimensions: appreciation, identification and participation. There were three forms of social interactions associated with popular culture that mediated learners’ language socialization: learners interacted with media characters, learners observed social interactions among characters and learners interacted with others about Chinese popular culture. In addition to teaching and self-learning, this study found that CAL learners favored peer socialization with Chinese friends to carry out this pedagogy of learning Mandarin through Chinese popular culture. Yet, perceived (or real) propaganda in Chinese popular culture, issues of learners’ heritage identity and preferences, and the informal, fragmented, and sometimes even archaic language found in popular culture suggest that a pedagogy drawing on popular culture, while promising, is far from straightforward and must be considered carefully. This study suggests that Mandarin teachers should facilitate class discussions of Chinese popular culture, and extracurricular activity planners should facilitate individual peer socialization between a Chinese learner and a Chinese peer. Finally, textbook writers could consider establishing corresponding websites for textbooks, on which learners can access resources about Chinese popular culture, and can discuss popular topics in Mandarin.
DEP Bulletin:Volume 39 Issue 23
Creators: name: No Name Supplied
Publisher: name: No Publisher Supplied
Year: 2015

description: The DEP bulletin is a semi-monthly publication of the New Jersey Department of Environmental Protection. It contains a list of construction permit applications recently filed or acted upon by the Department along with a calendar of events of interest, a schedule of public hearings, and Environmental Impact Statements acted upon during the period.
Two Dimensional Simulations of Pair-Instability Supernovae
Creators: name: Chen, Ke-Jung
name: Heger, Alexander
name: Almgren, Ann S.
Publisher: name: arXiv
Year: 2010
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: We present preliminary results from two dimensional numerical studies of pair instability supernova (PSN). We study nuclear burning, hydrodynamic instabilities and explosion of very massive stars. Use a new radiation-hydrodynamics code, CASTRO.
description: Proceedings of "The First Stars and Galaxies: Challenges for the Next Decade", Austin, Texas, March 8-11, 2010. 2 pages, 1 figure
SEQUENT: Towards Traceable Quantum Machine Learning using Sequential Quantum Enhanced Training
Creators: name: Altmann, Philipp
name: Sünkel, Leo
name: Stein, Jonas
name: Müller, Tobias
name: Roch, Christoph
name: Linnhoff-Popien, Claudia
Publisher: name: arXiv
Year: 2023
Subjects: subject: Quantum Physics (quant-ph)
subject: Machine Learning (cs.LG)
subject: FOS: Physical sciences
subject: FOS: Computer and information sciences

description: Applying new computing paradigms like quantum computing to the field of machine learning has recently gained attention. However, as high-dimensional real-world applications are not yet feasible to be solved using purely quantum hardware, hybrid methods using both classical and quantum machine learning paradigms have been proposed. For instance, transfer learning methods have been shown to be successfully applicable to hybrid image classification tasks. Nevertheless, beneficial circuit architectures still need to be explored. Therefore, tracing the impact of the chosen circuit architecture and parameterization is crucial for the development of beneficially applicable hybrid methods. However, current methods include processes where both parts are trained concurrently, therefore not allowing for a strict separability of classical and quantum impact. Thus, those architectures might produce models that yield a superior prediction accuracy whilst employing the least possible quantum impact. To tackle this issue, we propose Sequential Quantum Enhanced Training (SEQUENT) an improved architecture and training process for the traceable application of quantum computing methods to hybrid machine learning. Furthermore, we provide formal evidence for the disadvantage of current methods and preliminary experimental results as a proof-of-concept for the applicability of SEQUENT.
description: Published at ICAART 2023
Quantifying the costs of dive behaviours and foraging strategies in Steller sea lions (Eumetopias jubatus)
Creators: name: Goundie, Elizabeth Thomson
Publisher: name: University of British Columbia
Year: 2015

description: Air-breathing divers, such as marine mammals, should adjust their diving behaviours in relation to the depth and density of their prey to minimize the energetic costs and maximize the benefits of foraging. However, there is little experimental data to test these predictions or to develop models to predict the responses of marine mammals to changes in prey availability. The objectives of my study were to 1) determine how changes in prey availability affect dive behaviour and foraging efficiency in Steller sea lions (Eumetopias jubatus) and 2) develop models with data from free-diving captive Steller sea lions to estimate foraging costs in wild animals and evaluate energetic trade-offs between different foraging strategies. I measured the diving metabolic rate, dive durations, and food intake of 4 trained sea lions diving in the open ocean on simulated prey patches of high- or low-densities at 10 m and 40 m. I also measured diving metabolic rates of sea lions performing 4 controlled dive types that allowed me to estimate the separate costs of different dive components (i.e., surface time, bottom time, and transiting to and from depth). I found that animals diving on prey patches with low prey density altered their dive behaviours and spent proportionally less time actively foraging, which ultimately decreased their foraging efficiency. I also found that making single, longer dives were less energetically costly than making multiple shorter dives in a bout, but that the sea lions replenished oxygen stores more efficiently when making a bout of dives. Finally, I determined the metabolic cost of transiting to and from depth (20.5±13.0 ml O₂ min₋¹ kg₋¹) was greater than the cost of foraging during the bottom portion of a dive (13.5±4.1 ml O₂ min₋¹ kg₋¹). With these values, I generated a predictive equation to estimate the diving costs of free-ranging animals. Overall, my results indicate that Steller sea lions do alter their dive behaviour in relation to prey availability and that different foraging strategies have different energetic costs. These results can be used to understand how changes in prey availability affect the overall energy balance and health of Steller sea lions.
Closing in on the sources of cosmic reionization: first results from the GLASS-JWST program
Creators: name: Mascia, S.
name: Pentericci, L.
name: Calabro', A.
name: Treu, T.
name: Santini, P.
name: Yang, L.
name: Napolitano, L.
name: Roberts-Borsani, G.
name: Bergamini, P.
name: Grillo, C.
name: Rosati, P.
name: Vulcani, B.
name: Castellano, M.
name: Boyett, K.
name: Fontana, A.
name: Glazebrook, K.
name: Henry, A.
name: Mason, C.
name: Merlin, E.
name: Morishita, T.
name: Nanayakkara, T.
name: Paris, D.
name: Roy, N.
name: Williams, H.
name: Wang, X.
name: Brammer, G.
name: Bradac, M.
name: Chen, W.
name: Kelly, P. L.
name: Koekemoer, A. M.
name: Trenti, M.
name: Windhorst, R. A.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: The escape fraction of Lyman-continuum (LyC) photons ($f_{esc}$) is a key parameter for determining the sources of cosmic reionization at $z\geq 6$. At these redshifts, owing to the opacity of the intergalactic medium, the LyC emission cannot be measured directly. However, LyC leakers during the epoch of reionization could be identified using indirect indicators that have been extensively tested at low and intermediate redshifts. These include a high [OIII]/[OII] flux ratio, high star-formation surface density, and compact sizes. In this work, we present observations of 29 $4.5 \leq z \leq 8$ gravitationally lensed galaxies in the Abell 2744 cluster field. From a combined analysis of JWST-NIRSpec and NIRCam data, we accurately derived their physical and spectroscopic properties: our galaxies have low masses $(\log(M_\star)\sim 8.5)$, blue UV spectral slopes ($β\sim -2.1$), compact sizes ($r_e \sim 0.3-0.5$ kpc), and high [OIII]/[OII] flux ratios. We confirm that these properties are similar to those characterizing low-redshift LyC leakers. Indirectly inferring the fraction of escaping ionizing photons, we find that more than 80% of our galaxies have predicted $f_{esc}$ values larger than 0.05, indicating that they would be considered leakers. The average predicted $f_{esc}$ value of our sample is 0.12, suggesting that similar galaxies at $z\geq 6$ have provided a substantial contribution to cosmic reionization.
description: Accepted for publication in the 4. Extragalactic astronomy section of A&A, 12 pages, 8 figures
Topological Insulator Cell for Memory and Magnetic Sensor Applications
Creators: name: Fujita, T.
name: Jalil, M. B. A.
name: Tan, S. G.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We propose a memory device based on magnetically doped surfaces of 3D topological insulators. Magnetic information stored on the surface is read out via the quantized Hall effect, which is characterized by a topological invariant. Consequently, the read out process is insensitive to disorder, variations in device geometry, and imperfections in the writing process.
description: 4 pages, 2 figures. Updated figures and text
Worker-firm matching in a global economy
Creators: name: Tito, Maria Domenica
Publisher: name: University of British Columbia
Year: 2015

description: This thesis investigates the impact of international trade on the sorting patterns of workers across firms and analyzes the implications for welfare. The first essay builds a model of matching between heterogeneous workers and firms in presence of search frictions. Variation in the worker type at the firm level exists in equilibrium only because of search costs. When firms gain access to foreign markets their revenue potential increases. When stakes are high, matching with the right worker becomes particularly important because deviations from the ideal match quickly reduce the value of the relationship. Hence exporting firms select sets of workers that are less dispersed relative to the average. The second essay documents the difference in the sorting patterns of workers between exporters and non-exporters in a French matched employer-employee dataset. We proxy the type of each worker using her average wage over her job spells and construct measures of the average type and type dispersion at the firm level. We find that exporting firms tolerate a lower dispersion in the pool of workers they hire. The matching between exporting firms and workers is even tighter in sectors characterized by better exporting opportunities as measured by foreign demand or tariffs. We also confirm the conjecture in the literature that exporters pay higher wages because, among other factors, they employ better workers. The final chapter explores the implications for wage inequality using the French Employer-Employee Data. We find that the differences in sorting in large part account for the existing differences in the wage structure between exporters and non-exporters. Exporting firms tend to have higher wages but tolerate a lower dispersion. Using an alternative theory-based measure of residual wage inequality, we also find that the unexplained component tends to be smaller in exporting and more productive firms, even when controlling for some differences in workforce composition. This finding suggests that exporters are better able to overcome frictions in the labour market in order to move closer to their ideal worker.
Exploring the foundation of social diversity and coherence with a novel attraction-repulsion model framework
Creators: name: Cui, Peng-Bi
Publisher: name: arXiv
Year: 2023
Subjects: subject: Physics and Society (physics.soc-ph)
subject: FOS: Physical sciences
subject: 91Cxx

description: One widely-existed state --``harmony with diversity" in which individuals freely express various viewpoints to sustain integration of social diversity, but at the same time shared values ensure social coherence, can be considered as the foundation of social diversity and coherence, however, which has never attracted research attention. Its formation mechanism still remains unclear. To address this issue, this study proposes an attraction-repulsion model based on the general simple assumption that individuals tend to either reach an agreement with shared opinions or to amplify difference from others with distant opinions. It allows us to take account into the three core parameters: interaction strength, individuals' susceptibility and tolerance to others' opinions. We are concerned with the effect of not only time-varying topology but also fixed interactions imposed by static social network, where the tasks of heterogeneous individuals' attributes are also performed. Remarkably, the simple model rules successfully generate the three above phases except for fragmentation, along with three different transitions and the triple points. We find that sufficient susceptibility, intermediate interaction strength and high tolerance can benefit a balance between repulsive and attractive forces, and thus the emergence of "harmony with diversity". However, fixed interactions can introduce cluster-level self-reinforced mechanism which can unexpectedly promote polarization. Heterogeneous susceptibility or tolerance turns out to be an inhibiting factor, which should be avoided. A method to identify the phase boundaries through computing the maximum susceptibility of entropy and stand deviation of opinions, confirmed by numerical simulations, allows us to build phase diagrams and to locate where the triple points are.
description: 21 pages, 19 figures
Entanglement classification and \emph{non-k}-separability certification via Greenberger-Horne-Zeilinger-class fidelity
Creators: name: Płodzień, Marcin
name: Chwedeńczuk, Jan
name: Lewenstein, Maciej
name: Rajchel-Mieldzioć, Grzegorz
Publisher: name: arXiv
Year: 2024
Subjects: subject: Quantum Physics (quant-ph)
subject: Quantum Gases (cond-mat.quant-gas)
subject: FOS: Physical sciences

description: Many-body quantum systems can be characterised using the notions of \emph{k}-separability and entanglement depth. A quantum state is \emph{k}-separable if it can be expressed as a mixture of \emph{k} entangled subsystems, and its entanglement depth is given by the size of the largest entangled subsystem. In this paper we propose a multipartite entanglement measure that satisfies the following criteria: (i) it can be used with both pure and mixed states; (ii) it is encoded in a single element of the density matrix, so it does not require knowledge of the full spectrum of the density matrix; (iii) it can be applied to large systems; and (iv) it can be experimentally verified. The proposed method allows the certification of \emph{non-k}-separability of a given quantum state. We show that the proposed method successfully classifies three-qubit systems into known stochastic local operations and classical communication (SLOCC) classes, namely bipartite, \mbox{W-,} and GHZ-type entanglement. Furthermore, we characterise the \emph{non-k}-separability in known nine SLOCC classes of four-qubit states, absolutely maximally entangled states for five and six qubits and for arbitrary size qubit Dicke states.
description: Author's Accepted Manuscript
Improving Energy Saving of One-sided Matrix Decompositions on CPU-GPU Heterogeneous Systems
Creators: name: Chen, Jieyang
name: Liang, Xin
name: Zhao, Kai
name: Sabzi, Hadi Zamani
name: Bhuyan, Laxmi
name: Chen, Zizhong
Publisher: name: arXiv
Year: 2023
Subjects: subject: Distributed, Parallel, and Cluster Computing (cs.DC)
subject: FOS: Computer and information sciences

description: One-sided dense matrix decompositions (e.g., Cholesky, LU, and QR) are the key components in scientific computing in many different fields. Although their design has been highly optimized for modern processors, they still consume a considerable amount of energy. As CPU-GPU heterogeneous systems are commonly used for matrix decompositions, in this work, we aim to further improve the energy saving of one-sided matrix decompositions on CPU-GPU heterogeneous systems. We first build an Algorithm-Based Fault Tolerance protected overclocking technique (ABFT-OC) to enable us to exploit reliable overclocking for key matrix decomposition operations. Then, we design an energy-saving matrix decomposition framework, Bi-directional Slack Reclamation(BSR), that can intelligently combine the capability provided by ABFT-OC and DVFS to maximize energy saving and maintain performance and reliability. Experiments show that BSR is able to save up to 11.7% more energy compared with the current best energy saving optimization approach with no performance degradation and up to 14.1% Energy * Delay^2 reduction. Also, BSR enables the Pareto efficient performance-energy trade-off, which is able to provide up to 1.43x performance improvement without costing extra energy.
Conclusive evidence for a population of water-worlds around M-dwarfs remains elusive
Creators: name: Rogers, James G.
name: Schlichting, Hilke E.
name: Owen, James E.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: The population of small, close-in exoplanets is bifurcated into super-Earths and sub-Neptunes. We calculate physically motivated mass-radius relations for sub-Neptunes, with rocky cores and H/He dominated atmospheres, accounting for their thermal evolution, irradiation and mass-loss. For planets $\lesssim 10~$M$_\oplus$, we find that sub-Neptunes retain atmospheric mass fractions that scale with planet mass and show that the resulting mass-radius relations are degenerate with results for `water-worlds' consisting of a 1:1 silicate-to-ice composition ratio. We further demonstrate that our derived mass-radius relation is in excellent agreement with the observed exoplanet population orbiting M-dwarfs and that planet mass and radii alone are insufficient to determine the composition of some sub-Neptunes. Finally, we highlight that current exoplanet demographics show an increase in the ratio of super-Earths to sub-Neptunes with both stellar mass (and therefore luminosity) and age, which are both indicative of thermally driven atmospheric escape processes. Therefore, such processes should not be ignored when making compositional inferences in the mass-radius diagram.
description: 16 pages, 2 figures. Accepted for publication in ApJL
Delay, reliability, and trust in information dissemination in vehicular networks
Creators: name: Rostamzadeh, Karim
Publisher: name: University of British Columbia
Year: 2015

description: The cost of road accidents globally is more than ＄500 B every year. Intelligent Transportation Systems (ITS) is a promising solution and Vehicular Networks is an ideal candidate for providing a communication platform for ITS applications. Safety-critical applications form the main motivation for intelligent transportation systems. Studying the major concerns in such applications, i.e., delay and reliability, through mathematical analysis is extremely beneficial because it enables us to design optimized schemes. Such analysis is, however, challenging due to the dynamics of a vehicular network. In this research, we have three main contributions. First, we present a mathematical model to study delay and reliability of emergency message dissemination in vehicular networks. This model includes three modules to address effects of channel, contention, and partitioning on delivery delay. This is the first delay model to the best of our knowledge that does all of these, and it gives network architects insight into the limitations of the network and helps them tune parameters such as transmission power and slot time duration. Simulation studies indicate that our model does capture the delay characteristics of vehicular networks for both highway and urban scenarios. An interesting observation from the analytical model confirms the fact that using the vehicle density on the road is a good metric for setting the right forwarding probability in vehicles. We exploit this conclusion and as our second contribution, we propose a completely distributed forwarding strategy, called Middle Is Next or MIN. Extensive simulations affirm the effectiveness of MIN in terms of delay and single-hop reliability in comparison with other well-known routing methods. Trusted communication in vehicular networks is of crucial importance without which all efforts for minimizing the delay or maximizing the reliability could be voided. As our third contribution, we propose FACT: Framework for Application-oriented Context-aware Trust-based communication in vehicular networks. FACT assigns a trust value to each road segment and one to each neighbourhood, instead of each car. Thus, it scales up easily and is completely distributed. Experimental results demonstrate that FACT outperforms other well-known routing protocols since it routes the messages via trusted paths.
Behavior of hydrogen ions, atoms, and molecules in alpha-boron studied using density functional calculations
Creators: name: Wagner, Philipp
name: Ewels, Christopher P.
name: Suarez-Martinez, Irene
name: Guiot, Vincent
name: Cox, Stephen F. J.
name: Lord, James S.
name: Briddon, Patrick R.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Other Condensed Matter (cond-mat.other)
subject: FOS: Physical sciences

description: We examine the behaviour of hydrogen ions, atoms and molecules in alpha-boron using density functional calculations. Hydrogen behaves as a negative-U centre, with positive H ions preferring to sit off-center on inter-layer bonds and negative H ions sitting preferably at in-plane sites between three B12 icosahedra. Hydrogen atoms inside B12 icosahedral cages are unstable, drifting off-center and leaving the cage with only a 0.09 eV barrier. While H0 is extremely mobile (diffusion barrier 0.25 eV), H+ and H- have higher diffusion barriers of 0.9 eV. Once mobile these defects will combine, forming H2 in the interstitial void space, which will remain trapped in the lattice until high temperatures. Based on these results we discuss potential differences for hydrogen behaviour in beta-boron, and compare with experimental muon-implantation data.
Pressure, Intermittency, Singularity
Creators: name: Constantin, Peter
Publisher: name: arXiv
Year: 2023
Subjects: subject: Analysis of PDEs (math.AP)
subject: FOS: Mathematics
subject: 35Q35, 35Q86

description: We give conditions for regularity of solutions of three dimensional incompressible Navier-Stokes equations based on the pressure and on structure functions.
Additional file 3: of Essential genes of the macrophage response to Staphylococcus aureus exposure
Creators: name: Sun, Aixia
name: Zhang, Hongwei
name: Pang, Feng
name: Niu, Guifen
name: Chen, Jianzhong
name: Chen, Fei
name: Zhang, Jian
Publisher: name: figshare
Year: 2018
Subjects: subject: Biochemistry
subject: Microbiology
subject: FOS: Biological sciences
subject: Cell Biology
subject: Genetics
subject: Molecular Biology
subject: Pharmacology
subject: Immunology
subject: FOS: Clinical medicine
subject: Biological Sciences not elsewhere classified
subject: Mathematical Sciences not elsewhere classified
subject: Developmental Biology
subject: Infectious Diseases
subject: FOS: Health sciences

description: Table S3. Two hundred twenty-seven DEGs obtained in Comparison 2 (|log2(FC)| > 1.5 & adjusted p < 0.01). (DOCX 25 kb)