cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Evolution of cosmological event horizons in anisotropic universes
Creators: name: Kim, Hyeong-Chan
Publisher: name: arXiv
Year: 2012
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We study the evolution of cosmological event horizons in anisotropic Kasner universes in the presence of a positive cosmological constant by analyzing null geodesics. At later times, the asymptotic form of cosmological horizons is the same spherical surface as the de Sitter horizon. At the early times, however, it has non-spherical shape with its eccentricity decreases with time. The horizon area increases with time respecting the second law of thermodynamics. The initial shape of the cosmological horizon takes the form of a needle or pancake surface depending on the nature of the background spacetimes. We also discuss that the presence of the holographic dark energy will modify significantly the initial evolution of the anisotropic universes.
description: Minor corrections, 7 pages, 2 figures
Timing Channel in IaaS: How to Identify and Investigate
Creators: name: (:Unkn) Unknown
Publisher: name: My University
Year: 2019
Subjects: Digital investigation
IaaS security
timing channel

description: © 2013 IEEE. Recently, the Infrastructure as a Service Cloud (IaaS) (e.g., Amazon EC2) has been widely used by many organizations. However, some IaaS security issues create serious threats to its users. A typical issue is the timing channel. This kind of channel can be a cross-VM information channel, as proven by many researchers. Owing to the fact that it is covert and traceless, the traditional identification methods cannot build an accurate analysis model and obtain a compromised result. We investigated the underlying behavior of the timing channel from the perspective of the memory activity records and summarized the signature of the timing channel in the underlying memory activities. An identification method based on the long-term behavior signatures was proposed. We proposed a complete set of forensics steps including evidence extraction, identification, record reserve, and evidence reports. We studied four typical timing channels, and the experiments showed that these channels can be detected and investigated, even with the disturbances from normal processes.
The prevalence and impact of lysogeny among oral isolates of Enterococcus faecalis
Creators: name: (:Unkn) Unknown
Publisher: name: My University
Year: 2019
Subjects: Enterococcus faecalis
bacteriophage
lysogeny
phage ΦEf11
prophage

description: © 2019, © 2019 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group. Bacterial phenotypic properties are frequently influenced by the uptake of extrachromosomal genetic elements, such as plasmids and bacteriophage genomes. Such modifications can result in enhanced pathogenicity due to toxin production, increased toxin release, altered antigenicity, and resistance to antibiotics. In the case of bacteriophages, the phage genome can stably integrate into the bacterial chromosome as a prophage, to produce a lysogenic cell. Oral enterococcal strains have been isolated from subgingival plaque and the root canals of endodontically-treated teeth that have failed to heal. Previously, we isolated a bacteriophage, phage ɸEf11, induced from a lysogenic Enterococcus faecalis strain recovered from the root canal of a failed endodontic case. PCR analysis using phage ɸEf11-specific oligonucleotide primers, disclosed that lysogens containing ɸEf11 prophages were commonly found among oral E. faecalis strains, being detected in 19 of 61 (31%) strains examined. Furthermore, in comparison to an isogenic cured strain, cultures of a lysogen harboring an ɸEf11 prophage exhibited altered phenotypic characteristics, such as increased persistence at high density, enhanced biofilm formation, and resistance to a bacteriophage lytic enzyme. From these results we conclude that lysogeny is common among oral E. faecalis strains, and that it alters properties of the lysogenic cell.
The Optically Unbiased GRB Host (TOUGH) survey. IV. Lyman-alpha emitters
Creators: name: Milvang-Jensen, Bo
name: Fynbo, Johan P. U.
name: Malesani, Daniele
name: Hjorth, Jens
name: Jakobsson, Páll
name: Møller, Palle
Publisher: name: arXiv
Year: 2012
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: We report the results of a spectroscopic search for Lyman-alpha emission from gamma-ray burst host galaxies. Based on the well-defined TOUGH sample of 69 X-ray selected Swift GRBs, we have targeted the hosts of a subsample of 20 GRBs known from afterglow spectroscopy to be in the redshift range 1.8-4.5. We detect Lya emission from 7 out of the 20 hosts, with the typical limiting 3sigma line flux being 8E-18 erg/cm2/s, corresponding to a Lya luminosity of 6E41 erg/s at z=3. The Lya luminosities for the 7 hosts in which we detect Lya emission are in the range (0.6-2.3)E42 erg/s corresponding to star-formation rates of 0.6-2.1 Msun/yr (not corrected for extinction). The rest-frame Lya equivalent widths (EWs) for the 7 hosts are in the range 9-40A. For 6 of the 13 hosts for which Lya is not detected we place fairly strong 3sigma upper limits on the EW (<20A), while for others the EW is either unconstrained or has a less constraining upper limit. We find that the distribution of Lya EWs is inconsistent with being drawn from the Lya EW distribution of bright Lyman break galaxies at the 98.3% level, in the sense that the TOUGH hosts on average have larger EWs than bright LBGs. We can exclude an early indication, based on a smaller, heterogeneous sample of pre-Swift GRB hosts, that all GRB hosts are Lya emitters. We find that the TOUGH hosts on average have lower EWs than the pre-Swift GRB hosts, but the two samples are only inconsistent at the 92% level. The velocity centroid of the Lya line is redshifted by 200-700 km/s with respect to the systemic velocity, similar to what is seen for LBGs, possibly indicating star-formation driven outflows from the host galaxies. There seems to be a trend between the Lya EW and the optical to X-ray spectral index of the afterglow (beta_OX), hinting that dust plays a role in the observed strength and even presence of Lya emission. [ABRIDGED]
description: ApJ accepted (v2: minor changes in the Subject headings and reference list)
Algebraic Restriction Codes and their Applications
Creators: name: Aggarwal, Divesh
name: Döttling, Nico
name: Dujmovic, Jesko
name: Hajiabadi, Mohammad
name: Malavolta, Giulio
name: Obremski, Maciej
Publisher: name: CISPA
Year: 2023

description: Consider the following problem: You have a device that is supposed to compute a linear combination of its inputs, which are taken from some finite field. However, the device may be faulty and compute arbitrary functions of its inputs. Is it possible to encode the inputs in such a way that only linear functions can be evaluated over the encodings? I.e., learning an arbitrary function of the encodings will not reveal more information about the inputs than a linear combination. In this work, we introduce the notion of algebraic restriction codes (AR codes), which constrain adversaries who might compute any function to computing a linear function. Our main result is an information-theoretic construction AR codes that restrict any class of function with a bounded number of output bits to linear functions. Our construction relies on a seed which is not provided to the adversary. While interesting and natural on its own, we show an application of this notion in cryptography. In particular, we show that AR codes lead to the first construction of rate-1 oblivious transfer with statistical sender security from the Decisional Diffie-Hellman assumption, and the first-ever construction that makes black-box use of cryptography. Previously, such protocols were known only from the LWE assumption, using non-black-box cryptographic techniques. We expect our new notion of AR codes to find further applications, e.g., in the context of non-malleability, in the future.
In-medium effects on $K^{+}$ and $K^{-}$ spectra in lighter systems
Creators: name: Sood, Aman D.
name: Hartnack, Ch.
name: Aichelin, Jörg
Publisher: name: arXiv
Year: 2011
Subjects: subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We aim to explore the in-medium effects on the transverse momentum ($p_{T}$) spectra of $K^{+}$ and $K^{-}$ in lighter mass system $^{12}C+^{12}C$.
description: 3 pages, 1 fig. DAE BRNS Symposium on Nuclear Physics Dec 26-30, (2011), Visakhapatnam A.P. INDIA
Hypertonic stress induced changes of Pseudomonas fluorescens adhesion towards soil minerals studied by AFM
Creators: name: Abu Quba, Abd Alaziz
name: Goebel, Marc-Oliver
name: Karagulyan, Mariam
name: Miltner, Anja
name: Kästner, Matthias
name: Bachmann, Jörg
name: Schaumann, Gabriele E.
name: Diehl, Doerte
Publisher: name: [London] : Macmillan Publishers Limited, part of Springer Nature
Year: 2023
Subjects: subject: Microscopy, Atomic Force
subject: Minerals
subject: Osmotic Pressure
subject: Pseudomonas fluorescens
subject: Soil
subject: Dewey Decimal Classification::500 | Naturwissenschaften
subject: Dewey Decimal Classification::600 | Technik

description: Studying bacterial adhesion to mineral surfaces is crucial for understanding soil properties. Recent research suggests that minimal coverage of sand particles with cell fragments significantly reduces soil wettability. Using atomic force microscopy (AFM), we investigated the influence of hypertonic stress on Pseudomonas fluorescens adhesion to four different minerals in water. These findings were compared with theoretical XDLVO predictions. To make adhesion force measurements comparable for irregularly shaped particles, we normalized adhesion forces by the respective cell-mineral contact area. Our study revealed an inverse relationship between wettability and the surface-organic carbon content of the minerals. This relationship was evident in the increased adhesion of cells to minerals with decreasing wettability. This phenomenon was attributed to hydrophobic interactions, which appeared to be predominant in all cell–mineral interaction scenarios alongside with hydrogen bonding. Moreover, while montmorillonite and goethite exhibited stronger adhesion to stressed cells, presumably due to enhanced hydrophobic interactions, kaolinite showed an unexpected trend of weaker adhesion to stressed cells. Surprisingly, the adhesion of quartz remained independent of cell stress level. Discrepancies between measured cell–mineral interactions and those calculated by XDLVO, assuming an idealized sphere-plane geometry, helped us interpret the chemical heterogeneity arising from differently exposed edges and planes of minerals. Our results suggest that bacteria may have a significant impact on soil wettability under changing moisture condition.
Total destruction of invariant tori for the generalized Frenkel-Kontorova model
Creators: name: Su, Xifeng
name: Wang, Lin
Publisher: name: arXiv
Year: 2011
Subjects: subject: Dynamical Systems (math.DS)
subject: Mathematical Physics (math-ph)
subject: FOS: Mathematics
subject: FOS: Physical sciences

description: We consider generalized Frenkel-Kontorova models on higher dimensional lattices. We show that the invariant tori which are parameterized by continuous hull functions can be destroyed by small perturbations in the $C^r$ topology with $r<1$.
Blurtooth: Exploiting cross-transport key derivation in Bluetooth classic and Bluetooth low energy
Creators: name: Antonioli, Daniele
name: Tippenhauer, Nils Ole
name: Rasmussen, Kasper
name: Payer, Mathias
Publisher: name: CISPA
Year: 2023

description: Bluetooth is a pervasive wireless technology specified in an open standard. The standard defines Bluetooth Classic (BT) for high- throughput wireless services and Bluetooth Low Energy (BLE) very low-power ones. The standard also specifies security mechanisms, such as pairing, session establishment, and cross-transport key derivation (CTKD). CTKD enables devices to establish BT and BLE security keys by pairing just once. CTKD was introduced in 2014 with Bluetooth 4.2 to improve usability. However, the security im- plications of CTKD were not studied carefully. This work demonstrates that CTKD is a valuable and novel Blue- tooth attack surface. It enables, among others, to exploit BT and BLE just by targeting one of the two (i.e., Bluetooth cross-transport ex- ploitation). We present the design of the first cross-transport attacks on Bluetooth. Our attacks exploit issues that we identified in the specification of CTKD. For example, we find that CTKD enables an adversary to overwrite pairing keys across transports. We leverage these vulnerabilities to impersonate, machine-in-the-middle, and establish unintended sessions with any Bluetooth device support- ing CTKD. Since the presented attacks blur the security boundary between BT and BLE, we name them BLUR attacks. We provide a low-cost implementation of the attacks and test it on a broad set of devices. In particular, we successfully attack 16 devices with 14 unique Bluetooth chips from popular vendors (e.g., Cypress, Intel, Qualcomm, CSR, Google, and Samsung), with Bluetooth standard versions of up to 5.2. We discuss why the countermeasures in the Bluetooth are not effective against our attacks, and we develop and evaluate practical and effective alternatives.
Dipolar Bose-Einstein condensate for large scattering length
Creators: name: Young-S, Luis E.
name: Adhikari, S. K.
name: Muruganandam, P.
Publisher: name: arXiv
Year: 2012
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: FOS: Physical sciences

description: A uniform dilute Bose gas of known density has a universal behavior as the atomic scattering length tends to infinity at unitarity while most of its properties are determined by a universal parameter $ξ$ relating the energies of the noninteracting and unitary gases. The usual mean-field equation is not valid in this limit and beyond mean-field corrections become important. We use a dynamical model including such corrections to investigate a trapped disk-shaped dipolar Bose-Einstein condensate (BEC) and a dipolar BEC vortex for large scattering length. We study the sensitivity of our results on the parameter $ξ$ and discuss the possibility of extracting the value of this parameter from experimental observables.
Landed wisdoms : collaborating on museum education programmes with the Haida Gwaii Museum at Kaay Llnagaay
Creators: name: Baird, Jill Rachel
Publisher: name: University of British Columbia
Year: 2011

description: This dissertation is an adaptive case study/autoethnography used to examine the collaborative development of educational programming at the Haida Gwaii Museum at Kaay Llnagaay, in Skidegate, Haida Gwaii. The collaboration involves First Nations and non-First Nations working in a First Nations community museum context and seeks to learn ways to develop museum education programming that reflects Haida ways of knowing and to transfer this learning to non-First Nations museums. The study is grounded in the intersecting theories of Indigenous knowledge systems, postcolonialism and feminist poststructuralism, and critical and collaborative museologies. The research process involved a mix of methods including personal journaling, photo-documentation, participant interviews and observations. Fieldwork was undertaken over a sixteen month period. Kirkness and Barnhardt’s (1991) 4Rs were used to critically examine the collaborative process. The themes of relationship, and place and land were added to responsibility, reciprocity, relevance and respect. The results demonstrated that reciprocity and relevance were processes of give and take between colleagues, where the needs of all participants to see value in the process and be proud of the outcomes were recognized as critical for success. A major finding is that respectful relationships between First Nation and non-First Nations are needed for positive and productive collaborations and essential if the work undertaken is to foreground Indigenous knowledge in ways not normally incorporated into main-stream museum education programming. This study shows that through committed relationship building, spending time getting to know the people and the place, museum colleagues can contribute to a post-colonial museum practice, one argued here as a liminal museology. This means adapting established educational practices, listening and waiting for relevant local options to emerge.
School-based preventive dental program in rural communities of the republic of Armenia
Creators: name: (:Unkn) Unknown
Publisher: name: My University
Year: 2019
Subjects: caries prevention
primary schoolchildren
fluoride toothpaste
school-based intervention
Armenia

description: © 2019 Gasoyan, Safaryan, Sahakyan, Gasoyan, Aaronson and Bagramian. Objectives: This paper describes a school-based preventive dental program implemented in 14 rural schools within nine villages of Armenia. As part of the program, school-based toothbrushing stations (called Brushadromes) were installed in the participating schools. The intervention included school-based supervised toothbrushing with fluoride toothpaste and oral hygiene education. Methods: The study evaluates the prevalence and levels of dental caries among rural schoolchildren in 2013 (beforethe implementationof the preventiveprogram, referredto as a pre-intervention group) and 2017 (4 years after the start of the program, referred to as an intervention group) in two randomly selected villages where the program was implemented. A repeated cross-sectional study design was used. The prevalence of caries and the number of decayed, missing, and filled teeth in permanent dentition (DMFT) and primary dentition (dmft) were recorded among 6–7 and 10–11-year-old schoolchildren in 2013 (n = 166) and 2017 (n = 148). The pre-intervention and intervention groups include different children in the same age range, from the same villages,examinedatdifferenttimepoints. In both instances, theyrepresentedover95% of the 6–7 and 10–11-year-old student populations of the studied villages. Pearson Chi-square, Fisher’s Exact test, independent t-test, and quasi-likelihood Poisson regression were utilized for data analysis. Results: Schoolchildren involved in the intervention had significantly less decay levels compared to same-age pre-intervention groups. For 10–11-year-old schoolchildren involved in the program, the mean number of permanent teeth with caries was lower by a factor of 0.689 (lower by 31.1%), p = 0.008, 95% CI, 0.523; 0.902, compared to the 10–11-year-old pre-intervention group, after controlling for age, sex, child’s socio-economic vulnerability status, the village of residence, and the number of permanent teeth with fillings. Conclusions: The study indicates a significantly lower level of caries among schoolchildren in the studied two villages where the intervention was implemented. The described intervention is particularly suitable in rural settings where water fluoridation is not available and homes have limited availability of running water.
Stochastic Model Updating with Uncertainty Quantification: An Overview and Tutorial
Creators: name: Bi, Sifeng
name: Beer, Michael
name: Cogan, Scott
name: Mottershead, John
Publisher: name: Amsterdam [u.a.] : Elsevier
Year: 2023
Subjects: subject: Bayesian updating
subject: Model updating
subject: Model validation
subject: Uncertainty propagation
subject: Uncertainty quantification
subject: Verification and validation
subject: Dewey Decimal Classification::000 | Allgemeines, Wissenschaft::000 | Informatik, Wissen, Systeme::004 | Informatik

description: This paper presents an overview of the theoretic framework of stochastic model updating, including critical aspects of model parameterisation, sensitivity analysis, surrogate modelling, test-analysis correlation, parameter calibration, etc. Special attention is paid to uncertainty analysis, which extends model updating from the deterministic domain to the stochastic domain. This extension is significantly promoted by uncertainty quantification metrics, no longer describing the model parameters as unknown-but-fixed constants but random variables with uncertain distributions, i.e. imprecise probabilities. As a result, the stochastic model updating no longer aims at a single model prediction with maximum fidelity to a single experiment, but rather a reduced uncertainty space of the simulation enveloping the complete scatter of multiple experiment data. Quantification of such an imprecise probability requires a dedicated uncertainty propagation process to investigate how the uncertainty space of the input is propagated via the model to the uncertainty space of the output. The two key aspects, forward uncertainty propagation and inverse parameter calibration, along with key techniques such as P-box propagation, statistical distance-based metrics, Markov chain Monte Carlo sampling, and Bayesian updating, are elaborated in this tutorial. The overall technical framework is demonstrated by solving the NASA Multidisciplinary UQ Challenge 2014, with the purpose of encouraging the readers to reproduce the result following this tutorial. The second practical demonstration is performed on a newly designed benchmark testbed, where a series of lab-scale aeroplane models are manufactured with varying geometry sizes, following pre-defined probabilistic distributions, and tested in terms of their natural frequencies and model shapes. Such a measurement database contains naturally not only measurement errors but also, more importantly, controllable uncertainties from the pre-defined distributions of the structure geometry. Finally, open questions are discussed to fulfil the motivation of this tutorial in providing researchers, especially beginners, with further directions on stochastic model updating with uncertainty treatment perspectives.
Graph Unlearning
Creators: name: Chen, Min
name: Zhang, Zhikun
name: Wang, Tianhao
name: Backes, Michael
name: Humbert, Mathias
name: Zhang, Yang
Publisher: name: CISPA
Year: 2023

description: The right to be forgotten states that a data subject has the right to erase their data from an entity storing it. In the context of machine learning (ML), it requires the ML model provider to remove the data subject's data from the training set used to build the ML model, a process known as machine unlearning. While straightforward and legitimate, retraining the ML model from scratch upon receiving unlearning requests incurs a high computational overhead when the training set is large. To address this issue, a number of approximate algorithms have been proposed in the domain of image and text data, among which SISA (Sharded, Isolated, Sliced, and Aggregated) is the state-of-the-art solution. It randomly partitions the training set into multiple shards and trains a constituent model for each shard. However, directly applying SISA to the graph data can severely damage the graph structural information, and thereby the resulting ML model utility. In this paper, we propose GraphEraser, a novel machine unlearning framework tailored to graph data. Its contributions include two novel graph partition algorithms and a learning-based aggregation method. We conduct extensive experiments on five real-world graph datasets to illustrate the unlearning efficiency and model utility of GraphEraser. We observe that GraphEraser achieves 2.06$\times$ (small dataset) to 35.94$\times$ (large dataset) unlearning time improvement compared to retraining from scratch. On the other hand, GraphEraser achieves up to $62.5\%$ higher F1 score than that of random partitioning. In addition, our proposed learning-based aggregation method achieves up to $112\%$ higher F1 score than that of the majority vote aggregation.
The role of climate change awareness for trust in institutions in sub-Saharan Africa
Creators: name: Dirksmeier, Peter
name: Nolte, Kerstin
name: Mewes, Lars
name: Tuitjer, Leonie
Publisher: name: Bristol : IOP Publ.
Year: 2023
Subjects: subject: climate change awareness
subject: conflict
subject: mitigation policies
subject: sub-Saharan Africa
subject: trust in impartial institutions
subject: trust in partial institutions
subject: Dewey Decimal Classification::600 | Technik::690 | Hausbau, Bauhandwerk

description: Within the context of climate change in sub-Saharan Africa, trust in institutions is an important prerequisite to implement climate change adaptation and mitigation policies. There is a lack of systematic investigation of the relationship between climate change awareness, conflicts, and trust in institutions. We address this pressing research gap based on a regression analysis with trust in institutions as dependent variables, and climate change awareness and violence as independent variables drawing on Afrobarometer individual data and aggregated data on armed conflicts. Our main findings indicate that trust in institutions in sub-Saharan Africa is influenced by both the individual climate change awareness and the violence context. First, we find a negative relationship between those who are aware of climate change and trust in institutions. Second, we observe a socio-economic divide: young, urban and educated parts of the population as well as those who feel their ethnic group is treated unfairly do not trust institutions. Third, we see a regional divide: those far from political centres are not aware of climate change, and those close to the political centres do not trust institutions.
Comment on "Global Positioning System Test of the Local Position Invariance of Planck's Constant"
Creators: name: Berengut, J. C.
name: Flambaum, V. V.
Publisher: name: arXiv
Year: 2012
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: Atomic Physics (physics.atom-ph)
subject: Space Physics (physics.space-ph)
subject: FOS: Physical sciences

description: In their Letter, Kentosh and Mohageg [Phys. Rev. Lett. 108, 110801 (2012)] seek to use data from clocks aboard global positioning system (GPS) satellites to place limits on local position invariance (LPI) violations of Planck's constant, h. It is the purpose of this comment to show that discussing limits on variation of dimensional constants (such as h) is not meaningful; that even within a correct framework it is not possible to extract limits on variation of fundamental constants from a single type of clock aboard GPS satellites; and to correct an important misconception in the authors' interpretation of previous Earth-based LPI experiments.
description: Reply to article available here: arXiv:1203.0102
Epistasis and entrenchment of drug resistance in HIV-1 subtype B
Creators: name: (:Unkn) Unknown
Publisher: name: My University
Year: 2019
Subjects: HIV
co-evolutionary model
computational biology
drug resistance
entrenchment
epistasis
physics of living systems
systems biology
virus
Anti-HIV Agents
Drug Resistance, Viral
Epistasis, Genetic
HIV-1
Human Immunodeficiency Virus Proteins
Humans
Mutant Proteins
Mutation

description: Copyright Biswas et al. The development of drug resistance in HIV is the result of primary mutations whose effects on viral fitness depend on the entire genetic background, a phenomenon called ‘epistasis’. Based on protein sequences derived from drug-experienced patients in the Stanford HIV database, we use a co-evolutionary (Potts) Hamiltonian model to provide direct confirmation of epistasis involving many simultaneous mutations. Building on earlier work, we show that primary mutations leading to drug resistance can become highly favored (or entrenched) by the complex mutation patterns arising in response to drug therapy despite being disfavored in the wild-type background, and provide the first confirmation of entrenchment for all three drug-target proteins: protease, reverse transcriptase, and integrase; a comparative analysis reveals that NNRTI-induced mutations behave differently from the others. We further show that the likelihood of resistance mutations can vary widely in patient populations, and from the population average compared to specific molecular clones.
Polarization of Λ (Λ ̄) Hyperons along the Beam Direction in Au+Au Collisions at sNN =200 GeV
Creators: name: (:Unkn) Unknown
Publisher: name: My University
Year: 2019
Subjects: STAR Collaboration

description: © 2019 American Physical Society. The Λ (Λ̄) hyperon polarization along the beam direction has been measured in Au+Au collisions at sNN=200 GeV, for the first time in heavy-ion collisions. The polarization dependence on the hyperons' emission angle relative to the elliptic flow plane exhibits a second harmonic sine modulation, indicating a quadrupole pattern of the vorticity component along the beam direction, expected due to elliptic flow. The polarization is found to increase in more peripheral collisions, and shows no strong transverse momentum (pT) dependence at pT greater than 1 GeV/c. The magnitude of the signal is about 5 times smaller than those predicted by hydrodynamic and multiphase transport models; the observed phase of the emission angle dependence is also opposite to these model predictions. In contrast, the kinematic vorticity calculations in the blast-wave model tuned to reproduce particle spectra, elliptic flow, and the azimuthal dependence of the Gaussian source radii measured with the Hanbury Brown-Twiss intensity interferometry technique reproduce well the modulation phase measured in the data and capture the centrality and transverse momentum dependence of the polarization signal.
Research Capacity - Reality, Equality, Equity
Creators: name: Havemann, Jo
Publisher: name: Zenodo
Year: 2021
Subjects: Open Science
Open Access
Equity
Scholarship
Open Data
FAIR principles
CARE principles

description: At Access 2 Perspectives, we understand global equity in scholarly communication as the opportunity for researchers from around the world being able to consume and share research output based on Open Science, FAIR and CARE principles. Since research capacity varies drastically within and across world regions, local conditions such as available funding, research infrastructure, or internet connectivity should not interfere with the potential of academic success.
Binary black hole coalescence in the large-mass-ratio limit: the hyperboloidal layer method and waveforms at null infinity
Creators: name: Bernuzzi, Sebastiano
name: Nagar, Alessandro
name: Zenginoglu, Anil
Publisher: name: arXiv
Year: 2011
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We compute and analyze the gravitational waveform emitted to future null infinity by a system of two black holes in the large mass ratio limit. We consider the transition from the quasi-adiabatic inspiral to plunge, merger, and ringdown. The relative dynamics is driven by a leading order in the mass ratio, 5PN-resummed, effective-one-body (EOB), analytic radiation reaction. To compute the waveforms we solve the Regge-Wheeler-Zerilli equations in the time-domain on a spacelike foliation which coincides with the standard Schwarzschild foliation in the region including the motion of the small black hole, and is globally hyperboloidal, allowing us to include future null infinity in the computational domain by compactification. This method is called the hyperboloidal layer method, and is discussed here for the first time in a study of the gravitational radiation emitted by black hole binaries. We consider binaries characterized by five mass ratios, $ν=10^{-2,-3,-4,-5,-6}$, that are primary targets of space-based or third-generation gravitational wave detectors. We show significative phase differences between finite-radius and null-infinity waveforms. We test, in our context, the reliability of the extrapolation procedure routinely applied to numerical relativity waveforms. We present an updated calculation of the gravitational recoil imparted to the merger remnant by the gravitational wave emission. As a self consistency test of the method, we show an excellent fractional agreement (even during the plunge) between the 5PN EOB-resummed mechanical angular momentum loss and the gravitational wave angular momentum flux computed at null infinity. New results concerning the radiation emitted from unstable circular orbits are also presented.
description: 22 pages, 18 figures. Typos corrected. To appear in Phys. Rev. D
Towards predicting immersion in surround sound music reproduction from sound field features
Creators: name: Kiyan, Roman
name: Bergner, Jakob
name: Preihs, Stephan
name: Wycisk, Yves
name: Schössow, Daphne
name: Sander, Kilian
name: Peissig, Jürgen
name: Kopiez, Reinhard
Publisher: name: Les Ulis : EDP Sciences
Year: 2023
Subjects: subject: Auditory perception modeling
subject: Feature selection
subject: Multichannel loudspeaker reproduction
subject: Sound field analysis
subject: Spatial audio
subject: Dewey Decimal Classification::500 | Naturwissenschaften::530 | Physik

description: When evaluating surround sound loudspeaker reproduction, perceptual effects are commonly analyzed in relationship to different loudspeaker configurations. The presented work contributes to this by modeling perceptual effects based on acoustic properties of various reproduction formats. A model of immersion in music listening is derived from the results of an experimental study analyzing the psychological construct of immersive music experience. The proposed approach is evaluated with respect to the relationship between immersion ratings and sound field features obtained from re-recordings of the stimuli using a spherical microphone array at the listening position. Spatial sound field parameters such as inter-aural cross-correlation (IACC), diffuseness and directivity are found to be of particular relevance. Further, immersion is observed to reach a point of saturation with greater numbers of loudspeakers, which is confirmed to be predictable from the physical properties of the sound field. Although effects related to participants and musical pieces outweigh the impact of sound field features, the proposed approach is found to be suitable for predicting population-average ratings, i.e. immersion experienced by an average listener for unknown content. The proposed method could complement existing research on multichannel loudspeaker reproduction by establishing a more generalizable framework independent of particular speaker setups.
Get a Model! Model Hijacking Attack Against Machine Learning Models
Creators: name: Salem, Ahmed
name: Backes, Michael
name: Zhang, Yang
Publisher: name: CISPA
Year: 2023

description: Machine learning (ML) has established itself as a cornerstone for various critical applications ranging from autonomous driving to authentication systems. However, with this increasing adoption rate of machine learning models, multiple attacks have emerged. One class of such attacks is training time attack, whereby an adversary executes their attack before or during the machine learning model training. In this work, we propose a new training time attack against computer vision based machine learning models, namely model hijacking attack. The adversary aims to hijack a target model to execute a different task than its original one without the model owner noticing. Model hijacking can cause accountability and security risks since a hijacked model owner can be framed for having their model offering illegal or unethical services. Model hijacking attacks are launched in the same way as existing data poisoning attacks. However, one requirement of the model hijacking attack is to be stealthy, i.e., the data samples used to hijack the target model should look similar to the model’s original training dataset. To this end, we propose two different model hijacking attacks, namely Chameleon and Adverse Chameleon, based on a novel encoder-decoder style ML model, namely the Camouflager. Our evaluation shows that both of our model hijacking attacks achieve a high attack success rate, with a negligible drop in model utility.
Living mathematics education
Creators: name: Renert, Moses Eitan
Publisher: name: University of British Columbia
Year: 2011

description: This dissertation searches for possible sources of life in mathematics pedagogy. It is motivated by my observation that much of mathematics education of today is obstructed by inertia. We teach mathematics today using methods and educational philosophies that have changed little in decades of practice, and we generally avoid the harder question of why do it at all? I use Wilber’s (1995) integral theory, a broad metatheory of psychosocial development, to conceptualize life in general, and aspects of life in mathematics education in particular. Wilber’s epistemological framework, called AQAL, describes reality as manifesting in four quadrants – subjective, objective, intersubjective, and interobjective – and in multiple developmental levels. I use AQAL to examine what is revealed about life in mathematics education through these perspectival lenses. The dissertation studies evolutionary dimensions of five related phenomena in mathematics education: purposes of teaching and learning mathematics, human relations in mathematics classes, the subject matter of mathematics, teachers’ mathematical knowledge, and ecological sustainability. I connect the diverse evolutions of these phenomena to reveal extant developmental pathologies in mathematics education, such as the Platonic barrier and excessive objectification. Moving beyond critique, the synthesis gestures toward a new emergent pedagogy – living mathematics education – that evolves mathematics education past these pathologies. The new pedagogy is elaborated through the examples of an instructional unit on circles and the participatory research methodology of concept study. I provide specific suggestions how living mathematics pedagogy may be practiced through dialogical classes, a new purpose of healing the world, a curriculum of sustainability, a skillful blending of Platonic and non-Platonic mathematics, and an improvisatory disposition towards teaching.
X-ray emission from massive stars with magnetic fields
Creators: name: Oskinova, L. M.
name: Hamann, W. -R.
name: Cassinelli, J. P.
name: Brown, J. C.
name: Todt, H.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: We investigate the connections between the magnetic fields and the X-ray emission from massive stars. Our study shows that the X-ray properties of known strongly magnetic stars are diverse: while some comply to the predictions of the magnetically confined wind model, others do not. We conclude that strong, hard, and variable X-ray emission may be a sufficient attribute of magnetic massive stars, but it is not a necessary one. We address the general properties of X-ray emission from "normal" massive stars, especially the long standing mystery about the correlations between the parameters of X-ray emission and fundamental stellar properties. The recent development in stellar structure modeling shows that small scale surface magnetic fields may be common. We suggest a "hybrid" scenario which could explain the X-ray emission from massive stars by a combination of magnetic mechanisms on the surface and shocks in the stellar wind. The magnetic mechanisms and the wind shocks are triggered by convective motions in sub-photospheric layers. This scenario opens the door for a natural explanation of the well established correlation between bolometric and X-ray luminosities.
description: Accepted AN. 2011 Potsdam Thinkshop "Magnetic Fields in Stars and Exoplanets"
Model Stealing Attacks Against Inductive Graph Neural Networks
Creators: name: Shen, Yun
name: Xinlei.He
name: Han, Yufei
name: Zhang, Yang
Publisher: name: CISPA
Year: 2023

description: Many real-world data come in the form of graphs. Graph neural networks (GNNs), a new family of machine learning (ML) models, have been proposed to fully leverage graph data to build powerful applications. In particular, the inductive GNNs, which can generalize to unseen data, become mainstream in this direction. Machine learning models have shown great potential in various tasks and have been deployed in many real-world scenarios. To train a good model, a large amount of data as well as computational resources are needed, leading to valuable intellectual property. Previous research has shown that ML models are prone to model stealing attacks, which aim to steal the functionality of the target models. However, most of them focus on the models trained with images and texts. On the other hand, little attention has been paid to models trained with graph data, i.e., GNNs. In this paper, we fill the gap by proposing the first model stealing attacks against inductive GNNs. We systematically define the threat model and propose six attacks based on the adversary’s background knowledge and the responses of the target models. Our evaluation on six benchmark datasets shows that the proposed model stealing attacks against GNNs achieve promising performance。
Topographic cues of a novel bilayered scaffold modulate dental pulp stem cells differentiation by regulating YAP signalling through cytoskeleton adjustments
Creators: name: (:Unkn) Unknown
Publisher: name: My University
Year: 2019
Subjects: Actins
Adaptor Proteins, Signal Transducing
Cell Differentiation
Cell Proliferation
Cells, Cultured
Cues
Cytoskeleton
Dental Pulp
Humans
Odontogenesis
Osteogenesis
Stem Cells
Transcription Factors

description: © 2019 The Authors. Cell Proliferation Published by John Wiley & Sons Ltd. Objectives: Topographic cues can modulate morphology and differentiation of mesenchymal stem cells. This study aimed to determine how topographic cues of a novel bilayered poly (lactic-co-glycolic acid) (PLGA) scaffold affect osteogenic/odontogenic differentiation of dental pulp stem cells (DPSCs). Methods: The surface morphology of the scaffolds was visualized by scanning electron microscope, and the surface roughness was measured by profilometry. DPSCs were cultured on each side of the scaffolds. Cell morphology, expression of Yes-associated protein (YAP) and osteogenic/odontogenic differentiation were analysed by immunohistochemistry, real-time polymerase chain reaction, and Alizarin Red S staining. In addition, cytochalasin D (CytoD), an F-actin disruptor, was used to examine the effects of F-actin on intracellular YAP localisation. Verteporfin, a YAP transcriptional inhibitor, was used to explore the effects of YAP signalling on osteogenic/odontogenic differentiation of DPSCs. Results: The closed side of our scaffold showed smaller pores and less roughness than the open side. On the closed side, DPSCs exhibited enhanced F-actin stress fibre alignment, larger spreading area, more elongated appearance, predominant nuclear YAP localization and spontaneous osteogenic differentiation. Inhibition of F-actin alignments was correlated with nuclear YAP exclusion of DPSCs. Verteporfin restricted YAP localisation to the cytoplasm, down-regulated expression of early osteogenic/odontogenic markers and inhibited mineralization of DPSCs cultures. Conclusions: The surface topographic cues changed F-actin alignment and morphology of DPSCs, which in turn regulated YAP signalling to control osteogenic/odontogenic differentiation.
Dynamical fluctuations close to Jamming versus Vibrational Modes : a pedagogical discussion illustrated on hard spheres simulations, colloidal and granular experiments
Creators: name: Henkes, Silke
name: Brito, Carolina
name: Dauchot, Olivier
Publisher: name: arXiv
Year: 2011
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: Studying the jamming transition of granular and colloidal systems, has lead to a proliferation of theoretical and numerical results formulated in the language of the eigenspectrum of the dynamical matrix for these disordered system. Only recently however, these modes have been accessed experimentally in colloidal and granular media, computing the eigenmodes of the covariance matrix of the particle positions. At the same time new conceptual and methodological questions have appeared, regarding the interpretation of these results. In the present paper, we first give an overview of the theoretical framework which is appropriate to discuss the interpretation of the eigenmodes and eigenvalues of the correlation matrix in terms of the vibrational properties of these systems. We then illustrate several aspects of the statistical and data analysis techniques which are necessary to extract reliable results from experimental data. Concentrating on the case of hard sphere simulations, colloidal and granular experiments, we discuss how to test the existence of a metastable state, the statistical independence of the sampling, the effect of the experimental resolution, and the harmonic hypothesis underlying the approach, highlighting both its promises and limitations.
description: 22 pages, 14 figures
SSLGuard: A Watermarking Scheme for Self-supervised Learning Pre-trained Encoders
Creators: name: Cong, Tianshuo
name: Xinlei.He
name: Zhang, Yang
Publisher: name: CISPA
Year: 2023

description: Self-supervised learning is an emerging machine learning (ML) paradigm. Compared to supervised learning that leverages high-quality labeled datasets to achieve good performance, self-supervised learning relies on unlabeled datasets to pre-train powerful encoders which can then be treated as feature extractors for various downstream tasks. The huge amount of data and computational resources consumption makes the encoders themselves become a valuable intellectual property of the model owner. Recent research has shown that the ML model's copyright is threatened by model stealing attacks, which aims to train a surrogate model to mimic the behavior of a given model. We empirically show that pre-trained encoders are highly vulnerable to model stealing attacks. However, most of the current efforts of copyright protection algorithms such as fingerprinting and watermarking concentrate on classifiers. Meanwhile, the intrinsic challenges of pre-trained encoder's copyright protection remain largely unstudied. We fill the gap by proposing SSLGuard, the first watermarking algorithm for pre-trained encoders. Given a clean pre-trained encoder, SSLGuard embeds a watermark into it and outputs a watermarked version. The shadow training technique is also applied to preserve the watermark under potential model stealing attacks. Our extensive evaluation shows that SSLGuard is effective in watermark injection and verification, and is robust against model stealing and other watermark removal attacks such as pruning and finetuning.
title: Differential monitoring
title: IST Austria Technical Report
titleType: AlternativeTitle
Creators: name: Mühlböck, Fabian
name: Henzinger, Thomas A
Publisher: name: IST Austria
Year: 2021
Subjects: subject: 005
subject: Run-time verification
subject: Software engineering
subject: Implicit specification

description: We argue that the time is ripe to investigate differential monitoring, in which the specification of a program's behavior is implicitly given by a second program implementing the same informal specification. Similar ideas have been proposed before, and are currently implemented in restricted form for testing and specialized run-time analyses, aspects of which we combine. We discuss the challenges of implementing differential monitoring as a general-purpose, black-box run-time monitoring framework, and present promising results of a preliminary implementation, showing low monitoring overheads for diverse programs.