cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Mixed-dimensional coupled finite elements in FEniCS
Creators: name: Daversin-Catty, Cécile
name: Rognes, Marie E.
Publisher: name: Zenodo
Year: 2019

description: Mixed-dimensional partial differential equations (PDEs) are equations coupling unknown fields defined over domains of differing topological dimension. Such mixed-dimensional PDEs naturally arise in a wide range of fields including geology, bio-medicine, and fracture mechanics. Mixed-dimensional models can also be used to impose non-standard conditions over a subspace of lower dimension such as a part of the boundary or an interface between two domains, through a Lagrange multiplier.
 Finite element discretizations of mixed-dimensional PDEs involve nested meshes of heterogeneous topological dimension. The assembly of such systems is non-standard and non-trivial especially with regard to the terms involved in the interactions between the different domains. In other words, automated solution of mixed-dimensional PDEs requires the design of both generic high level software abstractions and lower level algorithms. While external FEniCS-based packages have been developed for simulating mixed-dimensional problems, there is also an important need for embedding these features as an intrinsic part of the FEniCS
 library. We introduce an automated framework dedicated to mixed-dimensional problems addressing this gap, which has already been used with diverse applications ranging from reservoir simulations to ion concentration dynamics models.
 In this talk, we give an overview of the abstractions and algorithms involved, with a focus on newly implemented features including parallel submeshes extraction and interface formulation handling. The introduced tools will be illustrated by concrete examples of applications in biomedicine.
The Arecibo Detection of the Coolest Radio-flaring Brown Dwarf
Creators: name: Route, Matthew
name: Wolszczan, Alex
Publisher: name: arXiv
Year: 2012
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: Radio detection provides unique means to measure and study magnetic fields of the coolest brown dwarfs. Previous radio surveys have observed quiescent and flaring emission from brown dwarfs down to spectral type L3.5, but only upper limits have been established for even cooler objects. We report the detection of sporadic, circularly polarized flares from the T6.5 dwarf, 2MASS J1047+21, with the Arecibo radio telescope at 4.75 GHz. This is by far the coolest brown dwarf yet detected at radio frequencies. The fact that such an object is capable of generating observable, coherent radio emission, despite its very low, ~900 K temperature, demonstrates the feasibility of studies of brown dwarfs in the meagerly explored LTY spectral range, using radio detection as a tool.
description: 6 pages, 2 figures. Accepted for publication in ApJL
Observing the universal screening of a Kondo impurity
Creators: name: Piquard, C.
name: Glidic, P.
name: Han, C.
name: Aassime, A.
name: Cavanna, A.
name: Gennser, U.
name: Meir, Y.
name: Sela, E.
name: Anthore, A.
name: Pierre, F.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: The Kondo effect, deriving from a local magnetic impurity mediating electron-electron interactions, constitutes a flourishing basis for understanding a large variety of intricate many-body problems. Its experimental implementation in tunable circuits has made possible important advances through well-controlled investigations. However, these have mostly concerned transport properties, whereas thermodynamic observations - notably the fundamental measurement of the spin of the Kondo impurity - remain elusive in test-bed circuits. Here, with a novel combination of a "charge" Kondo circuit with a charge sensor, we directly observe the state of the impurity and its progressive screening. We establish the universal renormalization flow from a single free spin to a screened singlet, the associated reduction in the magnetization, and the relationship between scaling Kondo temperature and microscopic parameters. In our device, a Kondo pseudospin is realized by two degenerate charge states of a metallic island, which we measure with a non-invasive, capacitively coupled charge sensor. Such pseudospin probe of an engineered Kondo system opens the way to the thermodynamic investigation of many exotic quantum states, including the clear observation of Majorana zero modes through their fractional entropy.
Utilizing historical failure data and finite element modeling to understand bridge vulnerability to scour
Creators: name: Wirkijowski, Dominic Maciej
Publisher: name: No Publisher Supplied
Year: 2023

description: The resilience and longevity of bridges are vital to infrastructure stability. While bridge failures due to hydraulic hazards, primarily scour, remain a predominant concern, bridge asset managers often overlook hazard-specific methods of bridge prioritization. This inadequacy, combined with the impracticality of large-scale failure analyses for civil engineers, amplifies the need for efficient vulnerability assessments. Given that scour is responsible for most bridge failures in the U.S., and its incidence is projected to rise with climate change-induced extreme weather, this research aims to provide tools and frameworks to proactively identify vulnerable structures.This work investigates historical bridge failure data to identify patterns and distinctive characteristics of bridges susceptible to scour. An early observation showed that single-span bridges were the most frequently affected, leading to an in-depth analysis centered on bridge abutment scour. Factors such as bridge age, abutment geometry, and superstructure type were considered significant characteristics of past bridge failure. To further substantiate these findings, finite element modeling was employed, providing insights into the scour mechanisms as they relate to these attributes. The model, characterized by parameters such as structure geometry, subgrade stiffness, and superstructure type, was systematically calibrated to track the performance of bridge abutments at varying scour states.The research conclusively determined bridge age, abutment length, and subgrade stiffness as primary characteristics of bridge sensitivity to scour failure. Utilizing these discoveries, the study suggests several bridge prioritization frameworks grounded in empirical findings and risk assessment concepts. This work serves as a stepping stone for bridge asset managers and civil engineers, promoting an informed, hazard-centric approach to bridge maintenance and design.
Pseudotensor mesons as three-body resonances
Creators: name: Roca, L.
Publisher: name: arXiv
Year: 2011
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We show that the lightest pseudotensor mesons J^{PC}=2^-+ can be regarded as molecules made of a pseudoscalar (P) 0^-+ and a tensor 2^++ meson, where the latter is itself made of two vector (V) mesons. The idea stems from the fact that the vector-vector interaction in s-wave and spin 2 is very strong, to the point of generating the 2^++ tensor mesons. On the other hand the interaction of a pseudoscalar with a vector meson in s-wave is also very strong and it generates dynamically the lightest axial-vector mesons. Therefore we expect the PVV interaction to be strongly attractive and thus able to build up quasibound PVV resonances. We calculate the three body PVV interaction by using the fixed center approximation to the Faddeev equations where the two vectors are clustered forming a tensor meson. We find clear resonant structures which can be identified with the pi_2(1670), eta_2(1645) and K^*_2(1770) (2^-+) pseudotensor mesons.
description: 10 pages
Optical Control Of Mass Ejection From Ferroelectric Liquid Droplets: A Possible Tool For The Actuation Of Complex Fluids
Creators: name: Marni, Stefano
name: Barboza, Raouf
name: Zaltron, Annamaria
name: Lucchetti, Liana
Publisher: name: arXiv
Year: 2023
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: We report on the optical control of the recently observed electromechanical instability of ferroelectric liquid droplets exposed to the photovoltaic field of a lithium niobate ferroelectric crystal substrate. The ferroelectric liquid is a nematic liquid crystal in which almost complete polar ordering of the molecular dipoles generates an internal macroscopic polarization locally collinear to the mean molecular long axis. Upon entering the ferroelectric phase, droplets irradiated by unfocused beam undergo an electromechanical instability and disintegrate by the explosive emission of fluid jets. We show here that the regions of jets emission can be controlled by focusing the light beam in areas close to the droplet's edge. Once emitted, the fluid jets can be walked by moving the beam up to millimeter distance from the mother droplet. Reverting the lithium niobate substrate, jets become thinner and show the tendency of being repelled by the beam instead of being attracted, thus offering an additional tool for their optical manipulation. These observations may pave the way to intriguing applications of ferroelectric nematic fluids related to manipulation, actuation, and control of soft, flexible materials.
description: 12 pages, 5 figures
Efficiently Explaining CSPs with Unsatisfiable Subset Optimization (extended algorithms and examples)
Creators: name: Gamba, Emilio
name: Bogaerts, Bart
name: Guns, Tias
Publisher: name: arXiv
Year: 2023
Subjects: subject: Artificial Intelligence (cs.AI)
subject: Logic in Computer Science (cs.LO)
subject: FOS: Computer and information sciences
subject: F.4.1
subject: 68T27

description: We build on a recently proposed method for stepwise explaining solutions of Constraint Satisfaction Problems (CSP) in a human-understandable way. An explanation here is a sequence of simple inference steps where simplicity is quantified using a cost function. The algorithms for explanation generation rely on extracting Minimal Unsatisfiable Subsets (MUS) of a derived unsatisfiable formula, exploiting a one-to-one correspondence between so-called non-redundant explanations and MUSs. However, MUS extraction algorithms do not provide any guarantee of subset minimality or optimality with respect to a given cost function. Therefore, we build on these formal foundations and tackle the main points of improvement, namely how to generate explanations efficiently that are provably optimal (with respect to the given cost metric). For that, we developed (1) a hitting set-based algorithm for finding the optimal constrained unsatisfiable subsets; (2) a method for re-using relevant information over multiple algorithm calls; and (3) methods exploiting domain-specific information to speed up the explanation sequence generation. We experimentally validated our algorithms on a large number of CSP problems. We found that our algorithms outperform the MUS approach in terms of explanation quality and computational time (on average up to 56 % faster than a standard MUS approach).
description: arXiv admin note: text overlap with arXiv:2105.11763
title: Embryotoxic Effects of Three Natural Occurring Veratrum Alkaloids and One Synthetic Analog using In Vitro Produced Bovine Embryos
Creators: name: Welch, Kevin D
name: Wang, Shiquan
name: Lee, Stephen T.
name: Gardner, Dale R.
name: Panter, Kip E.
Publisher: name: Utah State University
Year: 2023

description: Three natural occurring plant toxins from Veratrum californicum and one related synthetic analog were screened for embryotoxicity using in vitro bovine embryo production techniques. Bovine oocytes were aspirated from ovaries collected from a local abattoir and embryos were generated through in vitro maturation (IVM) and in vitro culture (IVC) procedures. The three natural steroidal alkaloids, cyclopamine, jervine and veratramine and the synthetic steroidal derivative of cyclopamine, cyclopamine-4-en-3-one, were added to IVM and IVC media at 12 μM. Oocytes were exposed to the toxins during maturation (IVM) and pre-implantation embryo during culture (IVC). Cleavage rates and embryo growth (morula and blastocyst production) and development through the hatched blastocyst stage were evaluated. Cyclopamine and cyclopamine-4-en-3-one inhibited cleavage rates and embryo growth and development of morulae and blastocysts in culture. Oocytes that were exposed to cyclopamine and cyclopamine-4-en-3-one during IVM only showed reduced cleavage rates and resulted in lower numbers of embryos that developed to the morula, blastocyst, and hatched blastocyst stages. The effects of these steroidal alkaloids on the oocyte during IVM and on the embryo during all stages of development up to and including the hatched blastocyst stage, demonstrates a dramatic cytotoxic effect on oocytes maturation and early pre-implantation embryos. This research also suggests that the Hedgehog signaling pathway may play a role in the maturing oocyte as well as the pre-implantation embryo. These in vitro fertilization techniques provide an economical, rapid through put and effective method to screen natural toxins, especially suspected reproductive toxins for cytotoxicity.
An Experiment to Locate the Site of TeV Flaring in M87
Creators: name: Harris, D. E.
name: Massaro, F.
name: Cheung, C. C.
name: Horns, D.
name: Raue, M.
name: Stawarz, L.
name: Wagner, S.
name: Colin, P.
name: Mazin, D.
name: Wagner, R.
name: Beilicke, M.
name: LeBohec, S.
name: Hui, M.
name: Mukherjee, R.
Publisher: name: arXiv
Year: 2011
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We describe a Chandra X-ray ToO project designed to isolate the site of TeV flaring in the radio galaxy M87. To date, we have triggered the Chandra observations only once (2010 April) and by the time of the first of our 9 observations, the TeV flare had ended. However, we found that the X-ray intensity of the unresolved nucleus was at an elevated level for our first observation. Of the more than 60 Chandra observations we have made of the M87 jet covering 9 years, the nucleus was measured at a comparably high level only 3 times. Two of these occasions can be associated with TeV flaring, and at the time of the third event, there were no TeV monitoring activities. From the rapidity of the intensity drop of the nucleus, we infer that the size of the emitting region is of order a few light days times the unknown beaming factor; comparable to the same sort of estimate for the TeV emitting region. We also find evidence of spectral evolution in the X-ray band which seems consistent with radiative losses affecting the non-thermal population of the emitting electrons within the unresolved nucleus.
description: Accepted for publication in the Astrophysical Journal (scheduled for 2011 Dec 10 issue, Vol 743 although this could change). 11 pages including 3 figures
LEA_D5.5 PCP INVITATION TO TENDERS / REQUEST FOR TENDERS TEMPLATE
Creators: name: Moreira, Tânia
name: Castro, Pedro
name: Solange Leal, Ana
name: Bedin, Sara
name: Löytty, Lasse
name: Dominguez, Sonia
Publisher: name: Zenodo
Year: 2020
Subjects: PCP
PPI
Invitation to tenders
Request for tenders

description: This document was produced within LEA’s strategy of enhancing stakeholders’ knowledge about the various phases of a PCP and PPI and their specific rules and documentation. The various public procurement laws and rules and its required documents might get away potentially interested parties, especially if we are referring to a not well-known procedure, as it is still the PCP and the PPI. This document was created to contribute to clarify and bring stakeholders closer to these procedures, so they feel more comfortable to take part in this type of processes. Specifically, this document addresses the PCP and focuses on one of the steps of “Phase 0” (see Figure 1), gathering useful information and guidelines to prepare a PCP Invitation to Tenders (ITT) / Request for Tender. The ITT presents the legal framework of a PCP, containing all the relevant and necessary information concerning the PCP (description of the services to be procured, available budget, timeline, conditions, etc.).
On global ACC for foliated threefolds
Creators: name: Liu, Jihao
name: Luo, Yujie
name: Meng, Fanjun
Publisher: name: arXiv
Year: 2023
Subjects: subject: Algebraic Geometry (math.AG)
subject: Dynamical Systems (math.DS)
subject: FOS: Mathematics
subject: 14E30, 37F75

description: In this paper, we prove the rational coefficient case of the global ACC for foliated threefolds. Specifically, we consider any lc foliated log Calabi-Yau triple $(X,\mathcal{F},B)$ of dimension $3$ whose coefficients belong to a set $Γ$ of rational numbers satisfying the descending chain condition, and prove that the coefficients of $B$ belong to a finite set depending only on $Γ$. To prove our main result, we introduce the concept of generalized foliated quadruples, which is a mixture of foliated triples and Birkar-Zhang's generalized pairs. With this concept, we establish a canonical bundle formula for foliations in any dimension. As for applications, we extend Shokurov's global index conjecture in the classical MMP to foliated triples and prove this conjecture for threefolds with nonzero boundaries and for surfaces. Additionally, we introduce the theory of rational polytopes for functional divisors on foliations and prove some miscellaneous results.
description: 28 pages. Final version
Hausdorff measures of different dimensions are isomorphic under the Continuum Hypothesis
Creators: name: Elekes, Márton
Publisher: name: arXiv
Year: 2011
Subjects: subject: Classical Analysis and ODEs (math.CA)
subject: FOS: Mathematics
subject: Primary 28A78, Secondary 26A16, 26A45, 28A05, 03E50

description: We show that the Continuum Hypothesis implies that for every $0
Mixed-dimensional models of the brain's waterscape with FEniCS
Creators: name: Daversin-Catty, Cécile
name: Rognes, Marie E.
Publisher: name: Zenodo
Year: 2018

description: The clearance of the metabolic waste in the body is handled by the lymphatic system. Except in the brain, which appears to be the only organ devoid of lymphatic channels. Indeed, the mechanisms underlying the clearance processes of the brain are still unknown, and the topic sparks debate and controversy. What is clear however, is that dysfunction of cerebral metabolic waste clearance is associated with neurodegenerative disorders such as Alzheimer’s or Parkinson’s diseases. The term the brain’s waterscape refers to the circulation, flow and exchange of tissue fluid and transport of solutes through the brain. While these processes are not fully understood yet, most hypotheses point out the major role of the cerebral blood vessels and possibly paravascular spaces. We propose to investigate these processes using a mathematical approach based on coupled mixed-dimensional models mimicking the vasculature and paravasculature as topologically one-dimensional structures embedded in a three-dimensional porous medium.
 This talk introduces a mixed-dimensional model dedicated to the mesoscale-macroscale interaction between the brain tissue, the vasculature and the paravasculature, aiming at gaining new insight into the waste clearance process of the brain. The development of this model relies on the FEniCS open source finite element library. We will also present dedicated features developed in a wider context of automating mixed-dimensional finite element in FEniCS. The introduced tools will be illustrated by concrete examples of applications highlighting their relevance for model in biomedicine in general and for the brain’s waterscape in particular.
Asbestosis and general health among migrant shipbreakers from northern Bangladesh
Creators: name: Courtice, Midori Nakano
Publisher: name: University of British Columbia
Year: 2010

description: In Bangladesh, shipbreaking is often carried out by internal migrant workers from the impoverished northern regions. Ships can contain hazardous substances such as polychlorinated biphenyls, heavy metals and asbestos, which are all recognized carcinogens. Work is done by hand, without heavy equipment, adequate training or protection, and with high potential for exposures. This pilot study examined asbestosis and non asbestos-related respiratory symptoms among these migrant workers. Shipbreakers were recruited from their home communities in northern Bangladesh. They were interviewed in Bangla, and received anteroposterior chest x-rays and physical exams. Information was collected on: a) respiratory symptoms using validated questions from the American Thoracic Society, b) work history and past occupational exposures, c) clinical history, d) attitudes around occupational health and safety, e) and knowledge of the potential heath risks and fate of asbestos. Chest x-rays were read by a B-reader for asbestosis diagnosis. One hundred and four male shipbreakers were recruited with average age 40 years and 2.5 years education. On average they had nine years shipbreaking experience and 17 years since first year of employment on the yards. Radiographic results indicated a six percent prevalence of asbestosis, and results from the interviews indicated a thirteen percent and eight percent prevalence of work-related cough and phlegm, and work-related shortness of breath, respectively. The prevalence of asbestosis appears lower than seen in previous studies of shipbuilders and ship-repairers. However, beach-based shipbreakers (steel plate loaders and cable-pullers) were overrepresented in comparison to ship-based (cutters and fitters) workers. This, and the small sample size, inclusion criteria, and a possibly exaggerated healthy worker effect, could have resulted in an underestimate of prevalence. Ships typical of those being dismantled contain several tons of asbestos; there is a need for improvements in exposure control, including educating the shipbreakers about asbestos and where it is found. Future research should focus on subjects who have worked closer to the source of exposure, as well as better characterizing the exposure and learning about the fate of the asbestos after it leaves the yards.
MemPool: A Scalable Manycore Architecture with a Low-Latency Shared L1 Memory
Creators: name: Riedel, Samuel
name: Cavalcante, Matheus
name: Andri, Renzo
name: Benini, Luca
Publisher: name: arXiv
Year: 2023
Subjects: subject: Hardware Architecture (cs.AR)
subject: FOS: Computer and information sciences

description: Shared L1 memory clusters are a common architectural pattern (e.g., in GPGPUs) for building efficient and flexible multi-processing-element (PE) engines. However, it is a common belief that these tightly-coupled clusters would not scale beyond a few tens of PEs. In this work, we tackle scaling shared L1 clusters to hundreds of PEs while supporting a flexible and productive programming model and maintaining high efficiency. We present MemPool, a manycore system with 256 RV32IMAXpulpimg "Snitch" cores featuring application-tunable functional units. We designed and implemented an efficient low-latency PE to L1-memory interconnect, an optimized instruction path to ensure each PE's independent execution, and a powerful DMA engine and system interconnect to stream data in and out. MemPool is easy to program, with all the cores sharing a global view of a large, multi-banked, L1 scratchpad memory, accessible within at most five cycles in the absence of conflicts. We provide multiple runtimes to program MemPool at different abstraction levels and illustrate its versatility with a wide set of applications. MemPool runs at 600 MHz (60 gate delays) in typical conditions (TT/0.80 V/25 °C) in 22 nm FDX technology and achieves a performance of up to 229 GOPS or 180 GOPS/W with less than 2% of execution stalls.
description: 14 pages, 17 figures, 2 tables, Published in IEEE Transactions on Computers
Diochus emarginatus Huang, Janak & Zhou 2024
Creators: name: Huang, Tian
name: Janák, Jiří
name: Zhou, Hong-Zhang
Publisher: name: Zenodo
Year: 2025
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Staphylinidae
Diochus
Diochus emarginatus

description: 13. Diochus emarginatus Huang, Janák & Zhou, 2024
(Fig 1G)
Diochus emarginatus Huang, Janák, and Zhou, 2024: 509 (Type locality: India: Garhwal (UP); Nepal; Thailand).
Type material examined. Holotype: male, INDIA: Garhwal (UP): 20 km au Sud de Chamba, 1150 m, 20. X. 79, I. Löbl (MHNG). Paratypes: THAILAND: Chiang Mai: 1 male, Doi Suthep, 1450 m, 4. XI. 1985, Burckhardt-Löbl (MHNG).
Diagnosis. This species is similar to Diochus guizhouensis and D. myanmarensis sp. nov. in appearance but can be distinguished by the shape of the male sternite VIII, which has an emargination on the middle of posterior margin, also on both sides, and possesses fascicular setae. Diochus conicollis is also similar but has numerous setae on posterior margin of male sternite VIII, but without fascicular setae, and pronotum is elliptical.
Distribution. India, Nepal, Thailand.
description: Published as part of Huang, Tian, Janák, Jiří & Zhou, Hong-Zhang, 2025, Revision of the genus Diochus Erichson (Coleoptera: Staphylinidae, Staphylininae, Diochini) from Thailand and Myanmar, pp. 105-142 in Zootaxa 5620 (1) on pages 139-140, DOI: 10.11646/zootaxa.5620.1.5, http://zenodo.org/record/15219019
Mixed-dimensional coupled finite elements in FEniCS
Creators: name: Daversin-Catty, Cécile
name: Rognes, Marie E.
Publisher: name: Zenodo
Year: 2018

description: Mixed-dimensional partial differential equations (PDEs) are equations coupling unknown fields defined over domains of differing topological dimension. Such mixed-dimensional PDEs naturally arise in a wide range of fields including geology, bio-medicine, and fracture mechanics. Mixed-dimensional models can also be used to impose non-standard conditions over a subspace of lower dimension such as a part of the boundary or an interface between two domains, through a Lagrange multiplier. Finite element discretizations of mixed-dimensional PDEs involve nested meshes of heterogeneous topological dimension. The assembly of such systems is non-standard and non-trivial especially with regard to the terms involved in the interactions between the different domains. In other words, automated solution of mixed-dimensional PDEs requires the design of both generic high level software abstractions and lower level algorithms. In this talk, we present a set of features developed as part of an automated framework dedicated to such problems in the FEniCS Project framework. The introduced tools will be illustrated by concrete examples of applications highlighting their relevance for model in biomedicine.
History of the Emanuel Hospital
Creators: name: Hurd, Lew
Publisher: name: University of Oregon. Medical School
Year: 1939
Subjects: subject: Legacy Emanuel Medical Center (Portland, OR)
subject: Emanuel Hospital. School of Nursing (Portland, OR)
subject: Wooley, Ivan Medhurst
subject: Hospital Administration
subject: Hospitals
subject: Nursing
subject: FOS: Health sciences
subject: History of Medicine
subject: Oregon--Portland

description: Lew Hurd reflects on the history of the Emanuel Hospital, now known as Legacy Emanuel Medical Center, in Portland, from the earliest stages of planning by Swedish Lutherans to full-swing operations nearly thirty years later. Hurd describes in detail the physical spaces of the hospital - which were innovative for the time - as well as financing concerns, the ever-present needs for expanding space and services, the governance by Lutheran churches near Portland, and support by the numerous doctors and nurses providing care for the people in their community. This talk was read before the University of Oregon Medical School History Club.
MARTSIA: Enabling Data Confidentiality for Blockchain-based Process Execution
Creators: name: Marangone, Edoardo
name: Di Ciccio, Claudio
name: Friolo, Daniele
name: Nemmi, Eugenio Nerio
name: Venturi, Daniele
name: Weber, Ingo
Publisher: name: arXiv
Year: 2023
Subjects: subject: Cryptography and Security (cs.CR)
subject: Multiagent Systems (cs.MA)
subject: FOS: Computer and information sciences

description: Multi-party business processes rely on the collaboration of various players in a decentralized setting. Blockchain technology can facilitate the automation of these processes, even in cases where trust among participants is limited. Transactions are stored in a ledger, a replica of which is retained by every node of the blockchain network. The operations saved thereby are thus publicly accessible. While this enhances transparency, reliability, and persistence, it hinders the utilization of public blockchains for process automation as it violates typical confidentiality requirements in corporate settings. In this paper, we propose MARTSIA: A Multi-Authority Approach to Transaction Systems for Interoperating Applications. MARTSIA enables precise control over process data at the level of message parts. Based on Multi-Authority Attribute-Based Encryption (MA-ABE), MARTSIA realizes a number of desirable properties, including confidentiality, transparency, and auditability. We implemented our approach in proof-of-concept prototypes, with which we conduct a case study in the area of supply chain management. Also, we show the integration of MARTSIA with a state-of-the-art blockchain-based process execution engine to secure the data flow.
Optimal Phase Description of Chaotic Oscillators
Creators: name: Schwabedal, Justus T. C.
name: Pikovsky, Arkady
name: Kralemann, Björn
name: Rosenblum, Michael
Publisher: name: arXiv
Year: 2011
Subjects: subject: Chaotic Dynamics (nlin.CD)
subject: FOS: Physical sciences

description: We introduce an optimal phase description of chaotic oscillations by generalizing the concept of isochrones. On chaotic attractors possessing a general phase description, we define the optimal isophases as Poincaré surfaces showing return times as constant as possible. The dynamics of the resultant optimal phase is maximally decoupled of the amplitude dynamics, and provides a proper description of phase resetting of chaotic oscillations. The method is illustrated with the Rössler and Lorenz systems.
description: 10 Pages, 14 Figures
Inflationary gravitational wave background as a tail effect
Creators: name: Jokela, Niko
name: Kajantie, K.
name: Laine, M.
name: Nurmi, Sami
name: Sarkkinen, Miika
Publisher: name: arXiv
Year: 2023
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: The free propagator of a massless mode in an expanding universe can be written as a sum of two terms, a lightcone and a tail part. The latter describes a subluminal (time-like) signal. We show that the inflationary gravitational wave background, influencing cosmic microwave background polarization, and routinely used for constraining inflationary models through the so-called $r$ ratio, originates exclusively from the tail part.
description: 8 pages. v2: minor updates
Assessing mechanisms for engagement in access management for public lands in southwestern Alberta
Creators: name: Haddock, Rachelle Leanne
Publisher: name: Environmental Design
Year: 2010
Subjects: Public lands
Recreation
Public engagement
Consultation

description: Bibliography: p. 126-137
description: Some pages are in colour.
description: This Master’s Degree Project describes efforts to bridge the gap between existing research and proposed recreation access management for an area of public lands located in southwestern Alberta, Canada. The study area consisted of provincial public lands experiencing increased pressure from both recreational and industrial activities. At the time of writing, there was no comprehensive recreation access management plan for the area. An Internet-based survey was used to examine: how recreation users perceive recreation access management issues, and the acceptability and desirability of different public consultation processes to assist with recreation access management planning. Nine hundred and forty five people responded to the survey. Respondents were categorized into several different groupings for analysis, including: age, membership to an organized recreation use group, motorized/non-motorized recreation users, gender, length of time spent recreating in the area, and residence. Quantitative analysis through factor analysis and multiple analysis of variance indicated significant differences in opinions about what is currently happening on the landscape and the need for access management within all groupings except place of residence (‘large city’ vs. ‘other community’). Non-parametric tests indicated there were no significant differences in desirability of public consultation types between genders; however significant differences in desirability of public consultation types existed between all other groupings. Mechanisms for engagement in access management planning could be designed with the opinions and public consultation preferences of these groups in mind.
One dimensional Markov random fields, Markov chains and Topological Markov fields
Creators: name: Chandgotia, Nishant
name: Han, Guangyue
name: Marcus, Brian
name: Meyerovitch, Tom
name: Pavlov, Ronnie
Publisher: name: arXiv
Year: 2011
Subjects: subject: Dynamical Systems (math.DS)
subject: Probability (math.PR)
subject: FOS: Mathematics
subject: 37B10, 60J10, 60J27

description: In this paper we show that any one-dimensional stationary, finite-valued Markov Random Field (MRF) is a Markov chain, without any mixing condition or condition on the support. Our proof makes use of two properties of the support $X$ of a finite-valued stationary MRF: 1) $X$ is non-wandering (this is a property of the support of any finite-valued stationary process) and 2) $X$ is a topological Markov field (TMF). The latter is a new property that sits in between the classes of shifts of finite type and sofic shifts, which are well-known objects of study in symbolic dynamics. Here, we develop the TMF property in one dimension, and we will develop this property in higher dimensions in a future paper. While we are mainly interested in discrete-time finite-valued stationary MRF's, we also consider continuous-time, finite-valued stationary MRF's, and show that these are (continuous-time) Markov chains as well.
description: 15 pages
A Morita equivalence for Hilbert C*-modules
Creators: name: Joita, Maria
name: Moslehian, Mohammad Sal
Publisher: name: arXiv
Year: 2012
Subjects: subject: Operator Algebras (math.OA)
subject: Functional Analysis (math.FA)
subject: FOS: Mathematics
subject: 46L08 (Primary) 46L05 (Secondary)

description: In this paper we introduce a notion of Morita equivalence for Hilbert C*-modules in terms of the Morita equivalence of the algebras of compact operators on Hilbert C*-modules. We investigate some properties of the new version of Morita equivalence and obtain some results. We then applied our results to study the continuous actions of locally compact groups on full Hilbert C*-modules. We present an extension of Green's theorem in the context of Hilbert C*-modules as well.
description: 10 pages, to appear in Studia Math
Supermassive black hole mass in the massive elliptical galaxy M87 from integral-field stellar dynamics using OASIS and MUSE with adaptive optics: assessing systematic uncertainties
Creators: name: Simon, David A.
name: Cappellari, Michele
name: Hartke, Johanna
Publisher: name: arXiv
Year: 2023
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: The massive elliptical galaxy M87 has been the subject of several supermassive black hole mass measurements from stellar dynamics, gas dynamics, and recently the black hole shadow by the Event Horizon Telescope (EHT). This uniquely positions M87 as a benchmark for alternative black hole mass determination methods. Here we use stellar kinematics extracted from integral-field spectroscopy observations with Adaptive Optics (AO) using MUSE and OASIS. We exploit our high-resolution integral field spectroscopy to spectrally decompose the central AGN from the stars. We derive an accurate inner stellar-density profile and find it is flatter than previously assumed. We also use the spectrally-extracted AGN as a reference to accurately determine the observed MUSE and OASIS AO PSF. We then perform Jeans Anisotropic Modelling (JAM), with a new flexible spatially-variable anisotropy, and measure the anisotropy profile, stellar mass-to-light variations, inner dark matter fraction, and black hole mass. Our preferred black hole mass is $M_{\rm BH}=(8.7\pm1.2 [\text{random}] \pm1.3 [\text{systematic}]) \times 10^9 \ M_\odot $. However, using the inner stellar density from previous studies, we find a preferred black hole mass of $M_{\rm BH} = (5.5^{+0.5}_{-0.3}) \times 10^9 \ M_\odot $, consistent with previous work. We find that this is the primary cause of the difference between our results and previous work, in addition to smaller contributions due to kinematics and modelling method. We conduct numerous systematic tests of the kinematics and model assumptions and conclude that uncertainties in the black hole mass of M87 from previous determinations may have been underestimated and further analyses are needed.
description: 21 pages, 17 figures, 4 tables, accepted by MNRAS
Towards coupled mixed dimensional finite elements in FEniCS
Creators: name: Daversin-Catty, Cécile
name: Rognes, Marie E.
Publisher: name: Zenodo
Year: 2017

description: In the brain, the vasculature twist and turn through the brain tissue as topologically one-dimensional structures embedded in three dimensions. In the Earth’s crust, topologically two-dimensional faults and one-dimensional fractures cut through the three-dimensional rock. In general, there is an abundance of examples that call for mathematical and numerical models coupling n < m and m dimensional spaces. This talk is intended to continue the discussion on how best to support such finite element spaces and associated finite element formulations in the FEniCS framework. Emphasis will be put on key motivating examples, key abstractions and structures and key challenges.
Electrostatic correlations in inhomogeneous charged fluids beyond loop expansion
Creators: name: Buyukdagli, Sahin
name: Achim, Cristian
name: Ala-Nissila, Tapio
Publisher: name: arXiv
Year: 2012
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: Electrostatic correlation effects in inhomogeneous symmetric electrolytes are investigated within a previously developed electrostatic self-consistent (SC) theory (R.R. Netz and H. Orland, Eur. Phys.J. E 11, 301 (2003)). To this aim, we introduce two computational approaches that allow to solve the SC equations beyond the loop expansion. Both approaches can handle the case of dielectrically discontinuous boundaries where the one-loop theory is known to fail. By comparing the theoretical results obtained from these schemes with the results of the MC simulations that we ran for ions at neutral single dielectric interfaces as well as with previous MC data for charged interfaces, we first show that the weak coupling (WC) Debye-Huckel (DH) theory remains quantitatively accurate up to the bulk ion density rhob=0.01 M, whereas the SC theory exhibits a good quantitative accuracy up to rhob=0.2 M. Then, we derive from the perturbative SC scheme the one-loop theory of asymmetrically partitioned salt systems around a dielectrically homogeneous charged surface. It is shown that correlation effects originate in these systems from a competition between the salt screening loss at the interface driving the ions to the bulk region, and the interfacial counterion screening excess attracting them towards the surface. In the case of weak surface charges, the interfacial salt screening loss is the dominant effect. As a result, correlations decrease the MF density of both coions and counterions. With increasing surface charge, the surface-attractive counterion screening excess starts to dominate, and correlation effects amplify in this regime the MF density of both type of ions. We also show that at a characteristic value of the electrostatic coupling parameter, electrostatic correlations result in a charge inversion effect.
Holographic dissipative space-time supersolids
Creators: name: Yang, Peng
name: Baggioli, Matteo
name: Cai, Zi
name: Tian, Yu
name: Zhang, Hongbao
Publisher: name: arXiv
Year: 2023
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Quantum Gases (cond-mat.quant-gas)
subject: FOS: Physical sciences

description: Driving a system out of equilibrium enriches the paradigm of spontaneous symmetry breaking, which could then take place not only in space but also in time. The interplay between temporal and spatial symmetries, as well as symmetries from other internal degrees of freedom, can give rise to novel nonequilibrium phases of matter. In this study, we investigate a driven-dissipative superfluid model using holographic methods and reveal the existence of a space-time supersolid (STS) phase which concomitantly breaks the time translation, spatial translation, and the internal U(1) symmetry. The holographic methods naturally include finite temperature effects, which enables us to explore the complex phase diagram of this model and observe a cascade of out-of-equilibrium phase transitions from the STS phase to a synchronized superfluid phase, and finally to a normal fluid phase, by increasing the temperature.
description: 9 pages, 7 figures
The muscle metaboreflex during exercise in chronic obstructive pulmonary disease
Creators: name: Sherman, Megan F. B.
Publisher: name: University of British Columbia
Year: 2010

description: Chronic obstructive pulmonary disease (COPD) is characterised by deteriorating lung and airway function. Altered peripheral skeletal muscle properties, favouring glycolytic metabolism, are also well-documented in this population. Skeletal muscle properties such as those found in COPD patients may have significant effects on the magnitude of the muscle metaboreflex. Hypotheses: It was hypothesized that the muscle metaboreflex would be magnified in people with COPD compared to healthy controls, and that disease severity and exercise capacity would be correlated with the magnitude of the muscle metaboreflex. Methods: Eleven people with mild-to-severe COPD (FEV₁.₀ = 56.3 ± 7.4% predicted) and 11 age- and gender- matched controls performed isometric handgrip exercise (IHG) for 2.5 minutes, at 35% MVC, followed by 2 minutes of post-exercise circulatory occlusion (PECO). Hemodynamic changes were measured throughout the protocol to assess the magnitude of the metaboreflex. Participants also performed a progressive cycle test to volitional exhaustion. Results: Heart rate, mean arterial pressure (MAP), leg blood flow and leg vascular resistance responses were similar between the COPD group and controls throughout IHG and PECO (% change from baseline) (p > 0.05). Heart rate was highest at minute 2.5 of IHG (COPD 18 ± 4%, control 18 ± 3%) and returned to baseline during PECO, while MAP peaked at minute 2.5 of IHG (COPD 29 ± 5%, control 30 ± 3%) and remained elevated throughout PECO (COPD 25 ± 3%, control 21 ± 2%). Total peripheral resistance rose more in the COPD group throughout the protocol and approached significance at minute 2 of PECO (COPD 39 ± 9, control 18 ± 4%, p = 0.09). Cardiac output remained significantly higher throughout IHG and PECO in the control group (IHG 2.5 min: COPD 0.08 ± 7, control 17 ± 4%, p = 0.01). There was no association between disease severity (r = -0.22, p = 0.32) or exercise capacity (r = -0.02, p=0.92) and the magnitude of the muscle metaboreflex. Conclusions: The muscle metaboreflex is preserved in people with COPD. The mechanisms responsible remain unclear, however, unchanged upper limb skeletal muscle properties and desensitization of peripheral afferents to metabolites are plausible explanations.
Noise Induced Universal Diffusive Transport in Fermionic Chains
Creators: name: Langlett, Christopher M.
name: Xu, Shenglong
Publisher: name: arXiv
Year: 2023
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We develop a microscopic transport theory in a randomly driven fermionic model with and without linear potential. The operator dynamics arise from the competition between noisy and static couplings, leading to diffusion regardless of ballistic transport or Stark localization in the clean limit. The universal diffusive behavior is attributed to a noise-induced bound state arising in the operator equations of motion at small momentum. By mapping the noise-averaged operator equation of motion to a one-dimensional non-hermitian hopping model, we analytically solve for the diffusion constant, which scales non-monotonically with noise strength, revealing regions of enhanced and suppressed diffusion from the interplay between onsite and bond dephasing noise, and a linear potential. For large onsite dephasing, the diffusion constant vanishes, indicating an emergent localization. On the other hand, the operator equation becomes the diffusion equation for strong bond dephasing and is unaffected by additional arbitrarily strong static terms that commute with the local charge, including density-density interactions. The bound state enters a continuum of scattering states at finite noise and vanishes. However, the bound state reemerges at an exceptional-like point in the spectrum after the bound-to-scattering state transition. We then characterize the fate of Stark localization in the presence of noise.
description: Updated references and new results included. Comments welcome
Two Disciplines, One Common Goal: Librarians and Educational Developers Collaborating to Enhance and Advance the Practice and Scholarship of Teaching and Learning
Creators: name: Hayden, K. Alix
name: Jeffs, Cheryl
Publisher: name: University of Calgary
Year: 2015

description: Innovate, collaborate, connect, explore, build, change, partner, lead, network - these action words are consistently being used in the literature on librarianship and educational development, with the intent to advance and enhance the practice and scholarship of teaching and learning (Mitchell & Mitchell, 2015; Sutherland, 2014; Williams, et al., 2013). This interactive workshop, developed by faculty from two different disciplines, library science and educational development, have joined together in one common goal: to build capacity in the search for teaching and learning literature and resources. Our approach is an open invitation extended across all disciplines, and applicable to all institutions (Chick & Poole, 2014). Our collaboration began with the recognition that anyone new to the teaching and learning literature search needs a starting point. Concurrently, the educational developers were building networks of teaching and learning partners. The opportunity to collaborate on professional and resource development was embraced, and as a result, workshops were implemented and co-hosted, and resource materials developed, including a teaching and learning research guide. These innovative approaches and creative resources are designed to enhance and advance the practice and scholarship of teaching and learning (Otto, 2014). Evidence from the workshop evaluations indicate the need to build capacity was being addressed. This interdisciplinary, engaging and hands-on workshop will be offered in the library computer lab. The learning outcome is: participants will explore and be able to identify, general and discipline specific, teaching and learning databases, journals, and resources.