cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Inverse methods: How feasible are spatially low-resolved capacity expansion modelling results when disaggregated at high spatial resolution?
Creators: name: Frysztacki, Martha Maria
name: Hagenmeyer, Veit
name: Brown, Tom
Publisher: name: arXiv
Year: 2022
Subjects: subject: Computational Engineering, Finance, and Science (cs.CE)
subject: FOS: Computer and information sciences

description: Spatially highly-resolved capacity expansion models are often simplified to a lower spatial resolution because they are computationally intensive. The simplification mixes sites with different renewable features while ignoring transmission lines that can cause congestion. As a consequence, the results may represent an infeasible system when the capacities are fed back at higher spatial detail. Thus far there has been no detailed investigation of how to disaggregate results and whether the spatially highly-resolved disaggregated model is feasible. This is challenging since there is no unique way to invert the clustering. This article is split into two parts to tackle these challenges. First, methods to disaggregate spatially low-resolved results are presented: (a) an uniform distribution of regional results across its original highly-resolved regions, (b) a re-optimisation for each region separately, (c) an approach that minimises the "excess electricity". Second, the resulting highly-resolved models' feasibility is investigated by running an operational dispatch. While re-optimising yields the best results, the third inverse method provides comparable results for less computational effort. Feasibility-wise, the study design strengthens that modelling countries by single regions is insufficient. State-of-the-art reduced models with 100-200 regions for Europe still yield 3%-7% of load-shedding, depending on model resolution and inverse method.
description: Post-print
From Symmetries to Commutant Algebras in Standard Hamiltonians
Creators: name: Moudgalya, Sanjay
name: Motrunich, Olexei I.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: High Energy Physics - Theory (hep-th)
subject: Mathematical Physics (math-ph)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: In this work, we revisit several families of standard Hamiltonians that appear in the literature and discuss their symmetries and conserved quantities in the language of commutant algebras. In particular, we start with families of Hamiltonians defined by parts that are local, and study the algebra of operators that separately commute with each part. The families of models we discuss include the spin-1/2 Heisenberg model and its deformations, several types of spinless and spinful free-fermion models, and the Hubbard model. This language enables a decomposition of the Hilbert space into dynamically disconnected sectors that reduce to the conventional quantum number sectors for regular symmetries. In addition, we find examples of non-standard conserved quantities even in some simple cases, which demonstrates the need to enlarge the usual definitions of symmetries and conserved quantities. In the case of free-fermion models, this decomposition is related to the decompositions of Hilbert space via irreducible representations of certain Lie groups proposed in earlier works, while the algebra perspective applies more broadly, in particular also to arbitrary interacting models. Further, the von Neumann Double Commutant Theorem (DCT) enables a systematic construction of local operators with a given symmetry or commutant algebra, potentially eliminating the need for "brute-force" numerical searches carried out in the literature, and we show examples of such applications of the DCT. This paper paves the way for both systematic construction of families of models with exact scars and characterization of such families in terms of non-standard symmetries, pursued in a parallel paper.
description: 18+23 pages, v2: Some sections reorganized, references added
High-Purity Entanglement of Hot Propagating Modes Using Nonreciprocity
Creators: name: Orr, Lindsay
name: Khan, Saeed A.
name: Buchholz, Nils
name: Kotler, Shlomi
name: Metelmann, A.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Physics (quant-ph)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Distributed quantum information processing and communication protocols demand the ability to generate entanglement among propagating modes. However, thermal fluctuations can severely limit the fidelity and purity of propagating entangled states, especially for low-frequency modes relevant for radio-frequency (RF) signals. Here we propose nonreciprocity as a resource to render continuous-variable entanglement of propagating modes robust against thermal fluctuations. By utilising a cold-engineered reservoir we break the symmetry of reciprocity in a standard two-mode squeezing interaction between a low- and a high-frequency mode, and show that the rerouting of thermal fluctuations allows the generation of flying entangled states with high purity. Our approach requires only pairwise Gaussian interactions and is thus ideal for parametric circuit QED implementations.
description: 9+8 pages, 8 figures. References added, typos corrected, two new sections added to appendix, two new figures added in appendix
Detection of a Pair Density Wave State in UTe$_2$
Creators: name: Gu, Qiangqiang
name: Carroll, Joseph P.
name: Wang, Shuqiu
name: Ran, Sheng
name: Broyles, Christopher
name: Siddiquee, Hasan
name: Butch, Nicholas P.
name: Saha, Shanta R.
name: Paglione, Johnpierre
name: Davis, J. C. Séamus
name: Liu, Xiaolong
Publisher: name: arXiv
Year: 2022
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: Spin-triplet topological superconductors should exhibit many unprecedented electronic properties including fractionalized electronic states relevant to quantum information processing. Although UTe$_2$ may embody such bulk topological superconductivity, its superconductive order-parameter $Δ(\mathbf{k})$ remains unknown. Many diverse forms for $Δ(\mathbf{k})$ are physically possible in such heavy fermion materials. Moreover, intertwined density waves of spin (SDW), charge (CDW) and pairs (PDW) may interpose, with the latter state exhibiting spatially modulating superconductive order-parameter $Δ(\mathbf{r})$, electron pair density and pairing energy-gap. Hence, the newly discovered CDW state in UTe$_2$ motivates the prospect that a PDW state may exist in this material. To search for it, we visualize the pairing energy-gap with $μ$$eV$-scale energy-resolution using superconductive STM tips. We detect three PDWs, each with peak-peak gap modulations circa 10 $μ$$eV$ and at incommensurate wavevectors $\mathbf{P}_{i=1,2,3}$ that are indistinguishable from the wavevectors $\mathbf{Q}_{i=1,2,3}$ of the prevenient CDW. Concurrent visualization of the UTe$_2$ superconductive PDWs and the non-superconductive CDWs reveals that every $\mathbf{P}_i$ : $\mathbf{Q}_i$ pair exhibits a relative phase $δϕ\approx π$. From these observations, and given UTe$_2$ as a spin-triplet superconductor, this PDW state should be a spin-triplet pair density wave. While such states do exist in superfluid $^{3}$He, for superconductors they are unprecedented.
description: 39 pages, 14 figures
Rate-equation approach for multi-level quantum systems
Creators: name: Liul, M. P.
name: Shevchenko, S. N.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Strong driving of quantum systems opens opportunities for both controlling and characterizing their states. For theoretical studying of these systems properties we use the rate-equation formalism. The advantage of such approach is its relative simplicity. We used the formalism for description of a two-level system (TLS) with further expanding it on a case of a multi-level system. Obtained theoretical results have good agreement with experiments. The presented approach can also be considered as one more way to explore properties of quantum systems and underlying physical processes such as for instance Landau-Zener-Stuckelberg-Majorana transitions and interference.
Joint Spatial-Angular Sparse Coding for dMRI with Separable Dictionaries
Creators: name: Schwab, Evan
name: Vidal, René
name: Charon, Nicolas
Publisher: name: arXiv
Year: 2016
Subjects: subject: Machine Learning (stat.ML)
subject: Computer Vision and Pattern Recognition (cs.CV)
subject: Quantitative Methods (q-bio.QM)
subject: FOS: Computer and information sciences
subject: FOS: Biological sciences

description: Diffusion MRI (dMRI) provides the ability to reconstruct neuronal fibers in the brain, $\textit{in vivo}$, by measuring water diffusion along angular gradient directions in q-space. High angular resolution diffusion imaging (HARDI) can produce better estimates of fiber orientation than the popularly used diffusion tensor imaging, but the high number of samples needed to estimate diffusivity requires longer patient scan times. To accelerate dMRI, compressed sensing (CS) has been utilized by exploiting a sparse dictionary representation of the data, discovered through sparse coding. The sparser the representation, the fewer samples are needed to reconstruct a high resolution signal with limited information loss, and so an important area of research has focused on finding the sparsest possible representation of dMRI. Current reconstruction methods however, rely on an angular representation $\textit{per voxel}$ with added spatial regularization, and so, for non-zero signals, one is required to have at least one non-zero coefficient per voxel. This means that the global level of sparsity must be greater than the number of voxels. In contrast, we propose a joint spatial-angular representation of dMRI that will allow us to achieve levels of global sparsity that are below the number of voxels. A major challenge, however, is the computational complexity of solving a global sparse coding problem over large-scale dMRI. In this work, we present novel adaptations of popular sparse coding algorithms that become better suited for solving large-scale problems by exploiting spatial-angular separability. Our experiments show that our method achieves significantly sparser representations of HARDI than is possible by the state of the art.
Covid-19: yesterday, today and tomorrow. The quality of Covid-19 management and the evaluation of the “Health” chapter of the Recovery Plan.
Creators: name: De Belvis, Antonio Giulio
name: Lonoce, Nicole
name: Banchieri, Giorgio
name: Scelsi, Silvia
name: Amoddeo, Caterina Elisabetta
name: Di Stanislao, Francesco
name: Raco, Manuela
name: De Mattia, Egidio
Publisher: name: Journal of Preventive Medicine and Hygiene
Year: 2022

description: Introduction: The Covid-19 pandemic represented an unprecedented challenge for the healthcare world and the introduction of a new stronger and believable project plays a fundamental role for the quality of work and the provision of qualitative care. Aim: The survey provided by ASIQUAS aims to examines the impact of “Health” chapter included in the Recovery Plan, through the assessment of management quality of the Covid-19 pandemic. Methods: Starting from a literature review, in September 2021, a web-based survey has been conducted and administered by email. It has been taken into account measures widely used by different healthcare structures in order to analyze the projects implemented in the face of pandemic and to evaluate the new real possibility to invest funds in new healthcare structures and projects. Results: The survey consists of 19 multiple choices and respondents were from different types of structures, including regional departments and regional health agencies (1.4%), universities, research centers and IRCCS (11%), hospitals and university polyclinics (34.2%), Local Health Authorities (39.7%), socio-health organizations and Others (13,7%). The pandemic has highlighted many vulnerabilities at both hospitals and territorial level. The major weaknesses revealed by the survey are mainly due to.the lack of support from new staff units and poor availability of specific training tools for Covid-19 procedures. The Recovery Plan is still unclear with a lot of concern about the implementation and many limits of diffusion. Conclusions: It becomes essential to guarantee a new effective and interoperative model of integration. Today we can start more aware for the implementation of a system closer to everyone’s needs, making shortcomings the new strength and starting point.
description: Journal of Preventive Medicine and Hygiene, Vol. 63 No. 3 (2022): 2022633
Suzaku Measurements of Hot Halo Emission at Outskirts for Two Poor Galaxy Groups: NGC 3402 and NGC 5129
Creators: name: Nugent, Jenna M.
name: Dai, Xinyu
name: Sun, Ming
Publisher: name: arXiv
Year: 2017
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We present Suzaku off-center observations of two poor galaxy groups, NGC 3402 and NGC 5129, with temperatures below 1 keV. Through spectral decomposition, we measured their surface brightnesses and temperatures out to 530 and 1430 times the critical density of the universe for NGC 3402 and NGC 5129, respectively. These quantities are consistent with extrapolations from existing inner measurements of the two groups. With the refined bolometric X-ray luminosities, both groups prefer $L_X$-$T$ relations without a break in the group regime. Furthermore, we have determined the electron number densities and hydrostatic masses at these radii. We found that the surface brightness and electron number density profiles require two $β$ model components, as well as the indication that a third $β$ model may be needed for NGC 3402. Adding the gas mass measured from the X-ray data and stellar mass from group galaxy members, we computed baryon fractions of $f_b$ = 0.0693 $\pm$ 0.0068 and $f_b$ = 0.095 $\pm$ 0.014 for NGC 3402 and NGC 5129, respectively. Combining other poor groups with well-measured X-ray emission to the outskirts, we found an average baryon fraction extrapolated to $r_{500}$ of $\overline{f_{b,500}}$ = 0.0912 $\pm$ 0.0050 for X-ray-bright groups with temperatures between 0.8 and 1.3 keV, extending existing constraints to lower-mass systems and indicating that significant baryon losses exist below approximately $r_{500}$.
description: 44 pages, 13 figures and 8 tables
Additional file 1 of Soluble TREM-1 plasma concentration predicts poor outcome in COVID-19 patients
Creators: name: Gibot, Sébastien
name: Lafon, Thomas
name: Jacquin, Laurent
name: Lefevre, Benjamin
name: Kimmoun, Antoine
name: Guillaumot, Anne
name: Losser, Marie-Reine
name: Douplat, Marion
name: Argaud, Laurent
name: De Ciancio, Guillaume
name: Jolly, Lucie
name: Touly, Nina
name: Derive, Marc
name: Malaplate, Catherine
name: Luc, Amandine
name: Baumann, Cédric
name: François, Bruno
Publisher: name: figshare
Year: 2023
Subjects: subject: Medicine
subject: Microbiology
subject: FOS: Biological sciences
subject: Cell Biology
subject: Pharmacology
subject: Biotechnology
subject: Chemical Sciences not elsewhere classified
subject: Immunology
subject: FOS: Clinical medicine
subject: Cancer
subject: Infectious Diseases
subject: FOS: Health sciences
subject: Virology

description: Additional file 1. Supplementary Table 1: Baseline characteristics according to soluble TREM-1 concentration in the conventional cohort patients. Supplementary Table 2: Baseline characteristics according to soluble TREM-1 concentration in the ICU cohort patients. Supplementary Figure 1: Plasma sTREM-1 concentration evolution according to outcome. In the Conventional cohort (left panel), sTREM-1 measurements were repeated on Mondays, Wednesdays, and Fridays; in the ICU patients, measurements were performed at days 4, 6, 8, 14, 21, and 28. The sTREM-1 concentration increased over time in the conventional cohort patients with a complicated outcome (p = 0.017) while it did not change significantly in the ICU patients.
The evolution of the internal structure of massive star forming regions in the Milky Way as revealed by ALMA
Creators: name: Dib, Sami
Publisher: name: arXiv
Year: 2022
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We analyze the structure of 15 protocluster forming regions in the Milky Way using their $1.3$ mm continuum emission maps from the ALMA-IMF large program. The analysis of the clouds structure is performed using the delta-variance spectrum technique. The calculated spectra display a self-similar regime on small scales as well as the presence of a prominent bump on larger scales and whose physical size, $L_{\rm hub}$, falls in the range of $\approx 7000$ au to $60000$ au. These scales correspond to the sizes of the most compact clumps within the protocluster forming clouds. A significant correlation is found between $L_{\rm hub}$ and the surface density of the free-free emission estimated from the integrated flux of the H41$α$ recombination line $\left(Σ_{\rm H41α}^{\rm free-free}\right)$ as well as a significant anti-correlation between $L_{\rm hub}$ and the ratio of the 1.3 mm to 3 mm continuum emission fluxes $\left(S_{\rm 1.3 mm}^{\rm cloud}/S_{\rm 3 mm}^{\rm cloud}\right)$. Smaller values of $\left(S_{\rm 1.3 mm}^{\rm cloud}/S_{\rm 3 mm}^{\rm cloud}\right)$ and larger values of $Σ_{\rm H41α}^{\rm free-free}$ correspond to more advanced evolutionary stages of the protocluster forming clumps. Hence, our results suggest that the sizes of the densest regions in the clouds are directly linked to their evolutionary stage and to their star formation activity with more evolved clouds having larger protocluster forming clumps. This is an indication that gravity plays a vital role in regulating the size and mass growth and star formation activity of these clumps with ongoing gas accretion
description: Accepted in MNRAS. Matches the published version
Inferring gene regulatory networks from single-cell data: a mechanistic approach
Creators: name: Herbach, Ulysse
name: Bonnaffoux, Arnaud
name: Espinasse, Thibault
name: Gandrillon, Olivier
Publisher: name: arXiv
Year: 2017
Subjects: subject: Molecular Networks (q-bio.MN)
subject: FOS: Biological sciences

description: The recent development of single-cell transcriptomics has enabled gene expression to be measured in individual cells instead of being population-averaged. Despite this considerable precision improvement, inferring regulatory networks remains challenging because stochasticity now proves to play a fundamental role in gene expression. In particular, mRNA synthesis is now acknowledged to occur in a highly bursty manner. We propose to view the inference problem as a fitting procedure for a mechanistic gene network model that is inherently stochastic and takes not only protein, but also mRNA levels into account. We first explain how to build and simulate this network model based upon the coupling of genes that are described as piecewise-deterministic Markov processes. Our model is modular and can be used to implement various biochemical hypotheses including causal interactions between genes. However, a naive fitting procedure would be intractable. By performing a relevant approximation of the stationary distribution, we derive a tractable procedure that corresponds to a statistical hidden Markov model with interpretable parameters. This approximation turns out to be extremely close to the theoretical distribution in the case of a simple toggle-switch, and we show that it can indeed fit real single-cell data. As a first step toward inference, our approach was applied to a number of simple two-gene networks simulated in silico from the mechanistic model and satisfactorily recovered the original networks. Our results demonstrate that functional interactions between genes can be inferred from the distribution of a mechanistic, dynamical stochastic model that is able to describe gene expression in individual cells. This approach seems promising in relation to the current explosion of single-cell expression data.
Reorganization of Intensive Care Units for the COVID-19 pandemic: effects on nursing sensitive outcomes
Creators: name: Pagnucci, Nicola
Publisher: name: Journal of Preventive Medicine and Hygiene
Year: 2022

description: Background: Since the first months of 2020 COVID-19 patients who were seriously ill due to the development of ARDS, required admission to the intensive care unit to ensure potentially life-saving mechanical ventilation and support for vital functions. To cope with this emergency, an extremely rapid reorganization of premises, services and staff, to dedicate an entire intensive care unit exclusively to SARS-CoV-2 patients and increasing the number of beds was essential. The aim of the study was to evaluate the effects of reorganization of the COVID-19 intensive care unit in terms of nursing sensitive outcomes. Methods: a retrospective observational study was conducted to compare nursing sensitive outcomes between pre-COVID period and COVID period. Results: Falls (0.0% and 0.4%, respectively), physical restraint (1.8% and 1.1%, respectively), and pressure ulcers (8.0% and 3.0%, respectively) were similar in the COVID and in the pre-COVID group. After adjusting for gender, age, BMI, and number of comorbidities, the incidence of bloodstream infections was significantly higher in the COVID group than in the pre-COVID group. There were no statistically significant differences in the incidence between the two groups regarding other evaluated outcomes. Conclusion: the selected nursing sensitive outcomes maintained similar values in the pre-COVID and COVID patient groups. Healthcare-related infections rate must be considered an important alarm signal of quality of nursing care especially in conditions of excessive workload, stress and the presence of less experienced staff increase.
description: Journal of Preventive Medicine and Hygiene, Vol. 63 No. 3 (2022): 2022633
Towards apparent convergence in asymptotically safe quantum gravity
Creators: name: Denz, Tobias
name: Pawlowski, Jan M.
name: Reichert, Manuel
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: The asymptotic safety scenario in gravity is accessed within the systematic vertex expansion scheme for functional renormalisation group flows put forward in \cite{Christiansen:2012rx,Christiansen:2014raa}, and implemented in \cite{Christiansen:2015rva} for propagators and three-point functions. In the present work this expansion scheme is extended to the dynamical graviton four-point function. For the first time, this provides us with a closed flow equation for the graviton propagator: all vertices and propagators involved are computed from their own flows. In terms of a covariant operator expansion the current approximation gives access to $Λ$, $R$, $R^2$ as well as $R_{μν}^2$ and higher derivative operators. We find a UV fixed point with three attractive and two repulsive directions, thus confirming previous studies on the relevance of the first three operators. In the infrared we find trajectories that correspond to classical general relativity and further show non-classical behaviour in some fluctuation couplings. We also find signatures for the apparent convergence of the systematic vertex expansion. This opens a promising path towards establishing asymptotically safe gravity in terms of apparent convergence.
description: 24 pages, 6 figures; journal version with updated references
FAIR-FATE: Fair Federated Learning with Momentum
Creators: name: Salazar, Teresa
name: Fernandes, Miguel
name: Araujo, Helder
name: Abreu, Pedro Henriques
Publisher: name: arXiv
Year: 2022
Subjects: subject: Machine Learning (cs.LG)
subject: Artificial Intelligence (cs.AI)
subject: Distributed, Parallel, and Cluster Computing (cs.DC)
subject: FOS: Computer and information sciences
subject: I.2.m
subject: 68T07

description: While fairness-aware machine learning algorithms have been receiving increasing attention, the focus has been on centralized machine learning, leaving decentralized methods underexplored. Federated Learning is a decentralized form of machine learning where clients train local models with a server aggregating them to obtain a shared global model. Data heterogeneity amongst clients is a common characteristic of Federated Learning, which may induce or exacerbate discrimination of unprivileged groups defined by sensitive attributes such as race or gender. In this work we propose FAIR-FATE: a novel FAIR FederATEd Learning algorithm that aims to achieve group fairness while maintaining high utility via a fairness-aware aggregation method that computes the global model by taking into account the fairness of the clients. To achieve that, the global model update is computed by estimating a fair model update using a Momentum term that helps to overcome the oscillations of non-fair gradients. To the best of our knowledge, this is the first approach in machine learning that aims to achieve fairness using a fair Momentum estimate. Experimental results on real-world datasets demonstrate that FAIR-FATE outperforms state-of-the-art fair Federated Learning algorithms under different levels of data heterogeneity.
description: This preprint has not undergone peer review or any post-submission improvements or corrections. The Version of Record of this contribution is published in ICCS 2023 - Lecture Notes in Computer Science, vol 14073, Springer, and is available online at https://doi.org/10.1007/978-3-031-35995-8_37
On rigid varieties with projective reduction
Creators: name: Li, Shizhang
Publisher: name: arXiv
Year: 2017
Subjects: subject: Algebraic Geometry (math.AG)
subject: Number Theory (math.NT)
subject: FOS: Mathematics

description: In this paper, we study smooth proper rigid varieties which admit formal models whose special fibers are projective. The main theorem asserts that the identity components of the associated rigid Picard varieties will automatically be proper. Consequently, we prove that p-adic Hopf varieties will never have a projective reduction. The proof of our main theorem uses the theory of moduli of semistable coherent sheaves.
description: v1: 15 pages; v2: 18 pages, final and published version
First wave of COVID-19 pandemic in Madrid: handling the unexpected in a tertiary hospital
Creators: name: Hernández-Rivas, Lucía
name: Fernández-Bretón, Eva
name: Pedraz Gonzalez-Tablas, Teresa
name: García-Vaz, Claudia
name: Cantero-Escribano, José Miguel
name: Castro-Martínez, Mercedes
name: Pérez-Blanco, Verónica
name: Robustillo-Rodela, Ana
Publisher: name: Journal of Preventive Medicine and Hygiene
Year: 2022

description: The COVID-19 pandemic was declared on March 11th, 2020. By the end of January, the first imported cases were detected in Spain and, by March, the number of cases was growing exponentially, causing the implementation of a national lockdown. Madrid has been one of the most affected regions in terms of both cases and deaths. The aim of this study is to describe the epidemic curve and the epidemiological features and outcomes of COVID-19 patients hospitalized in La Paz University Hospital, a tertiary hospital located in Madrid. We included confirmed and probable COVID-19 cases admitted to our centre from February 26th to June 1st, 2020. We studied trends in hospitalization and ICU admissions using joinpoint regression analysis. A sample of 2970 patients was obtained. Median age was 70 years old (IQR 55 – 82) and 54.8% of them were male. ICU admission rate was 8.7% with a mortality rate of 45.7%. Global CFR was 21.8%. Median time from symptom onset to death was 14 days (IQR 9 – 22). We detected an admissions peak on March 21st followed by a descending trend, matching national and regional data. Age and sex distribution were comparable to further series nationally and in western countries.
description: Journal of Preventive Medicine and Hygiene, Vol. 63 No. 3 (2022): 2022633
Simultaneous multiple change-point and factor analysis for high-dimensional time series
Creators: name: Barigozzi, Matteo
name: Cho, Haeran
name: Fryzlewicz, Piotr
Publisher: name: arXiv
Year: 2016
Subjects: subject: Methodology (stat.ME)
subject: FOS: Computer and information sciences

description: We propose the first comprehensive treatment of high-dimensional time series factor models with multiple change-points in their second-order structure. We operate under the most flexible definition of piecewise stationarity, and estimate the number and locations of change-points consistently as well as identifying whether they originate in the common or idiosyncratic components. Through the use of wavelets, we transform the problem of change-point detection in the second-order structure of a high-dimensional time series, into the (relatively easier) problem of change-point detection in the means of high-dimensional panel data. Also, our methodology circumvents the difficult issue of the accurate estimation of the true number of factors in the presence of multiple change-points by adopting a screening procedure. We further show that consistent factor analysis is achieved over each segment defined by the change-points estimated by the proposed methodology. In extensive simulation studies, we observe that factor analysis prior to change-point detection improves the detectability of change-points, and identify and describe an interesting `spillover' effect in which substantial breaks in the idiosyncratic components get, naturally enough, identified as change-points in the common components, which prompts us to regard the corresponding change-points as also acting as a form of `factors'. Our methodology is implemented in the R package {\tt factorcpt}, available from CRAN.
description: 64 pages, to appear in the Journal of Econometrics
Charging by quantum measurement
Creators: name: Yan, Jia-shun
name: Jing, Jun
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We propose a quantum charging scheme fueled by measurements on ancillary qubits serving as disposable chargers. A stream of identical qubits are sequentially coupled to a quantum battery of $N+1$ levels and measured by projective operations after joint unitary evolutions of optimized intervals. If charger qubits are prepared in excited state and measured on ground state, then their excitations (energy) can be near-perfectly transferred to battery by iteratively updating the optimized measurement intervals. Starting from its ground state, the battery could be constantly charged to an even higher energy level. Starting from a thermal state, the battery could also achieve a near-unit ratio of ergotropy and energy through less than $N$ measurements, when a population inversion is realized by measurements. If charger qubits are prepared in ground state and measured on excited state, useful work extracted by measurements alone could transform the battery from a thermal state to a high-ergotropy state before the success probability vanishes. Our operations in charging are more efficient than those without measurements and do not invoke the initial coherence in both battery and chargers. Particularly, our finding features quantum measurement in shaping nonequilibrium systems.
A Time-Efficient, Data Driven Modelling Approach For Predicting The Geomagnetic Impact of Coronal Mass Ejections
Creators: name: Roy, Souvik
name: Nandy, Dibyendu
Publisher: name: arXiv
Year: 2022
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Space Physics (physics.space-ph)
subject: FOS: Physical sciences

description: To understand the global-scale physical processes behind coronal mass ejection (CME)-driven geomagnetic storms and predict their intensity as a space weather forecasting measure, we develop an interplanetary CME flux rope-magnetosphere interaction module using 3D magnetohydrodynamics. The simulations adequately describe ICME-forced dynamics of the magnetosphere including the imposed magnetotail torsion. These interactions also result in induced currents which is used to calculate the geomagnetic perturbation. Through a suitable calibration, we estimate a proxy of geoeffectiveness -- the Storm Intensity index (STORMI) -- that compares well with the Dst/SYM-H Index. Simulated impacts of two contrasting coronal mass ejections quantified by the STORMI index exhibit a high linear correlation with the corresponding Dst and SYM-H indices. Our approach is relatively simple, has fewer parameters to be fine-tuned, is time-efficient compared to complex fluid-kinetic methods. Furthermore, we demonstrate that flux rope erosion does not significantly affect our results. Thus our method has the potential to significantly extend the time window for predictability -- an outstanding challenge in geospace environment forecasting -- if early predictions of near-Earth CME flux rope structures based on near-Sun observations are available as inputs. This study paves the way for early warnings based on operational predictions of CME-driven geomagnetic storms.
description: 17 Pages, 8 figures, Published in APJL
Proyecto Mary Jo Deegan. Maria Ossowska
Creators: name: Navarro-Fosar, María-Rocío
name: Díaz Martínez, Capitolina
Publisher: name: Zenodo
Year: 2025
Subjects: subject: Sociology
subject: FOS: Sociology
subject: Women
subject: sociology of moral
subject: science of science
subject: Poland

description: Artículo sobre la vida, obra y sociología de Maria Ossowska.
title: Geoscience towards net zero - Advancing Australia's Green Steel potential workshop
Creators: name: M., Haynes
name: K., Anastasi
name: Z., Weng
name: A., Feitz
name: P., Grubnic
name: C., Simkus
name: S.D.C., Walsh
name: C., Wang
name: M., Haynes
name: D., Dwyer
name: J., Selway
Publisher: name: Commonwealth of Australia (Geoscience Australia)
Year: 2024
Subjects: subject: EFTF – Exploring for the Future
subject: Economic Fairways
subject: Hydrogen studies
subject: Australia’s Resources Framework
subject: Australia’s Future Energy Resources
subject: Hydrogen
subject: Green steel
subject: Iron
subject: Decarbonisation
subject: Other Earth Sciences
subject: FOS: Earth and related environmental sciences
subject: Engineering
subject: Published_External

description: The energy and resources industries are two essential pillars of Australia’s economy and vital sectors in the global transition to a sustainable and net-zero economy. To enhance Australia’s competitiveness, there is an urgent need to explore technical and strategic challenges and opportunities to unlock domestic hydrogen and green steel development pathways that are suitable for the Australian resources and manufacturing ecosystem.
Held on 30 August 2023 in Perth, Western Australia, this workshop provided Australian stakeholders in the hydrogen, iron ore and government sectors a forum to share, discuss and provide insight on a broad range of aspects relevant to hydrogen and green steel development opportunities across Australia—including identifying investment hurdles, technical challenges and knowledge gaps, and fostering new innovation and collaboration opportunities.
As part of the Exploring for the Future program, Geoscience Australia, in collaboration with Monash University, premiered its Green Steel Economic Fairways tool, which utilises geoscience knowledge and data to highlight regional opportunities of high economic potential for hydrogen and green steel industries in Australia.
The recording of the workshop presentations is available on YouTube.
[Rezension zu:] Jost Bürgi, Kepler und der Kaiser : Uhrmacher, Instrumentenbauer, Astronom, Mathematiker 1552-1632. Von Fritz Staudacher. Zurich : Verlag Neue Zucher Zeitung, 2013
Creators: name: Schmid, Jost
Publisher: name: Verlag Cartographica Helvetica
Year: 2014
Subjects: subject: 920 Biografien, Genealogie, Insignien
subject: Bürgi, Jost

description: In: Cartographica Helvetica 49 (2014), S. 59
Kuramoto variables as eigenvalues of unitary matrices
Creators: name: Novaes, Marcel
name: de Aguiar, Marcus A. M.
Publisher: name: arXiv
Year: 2024
Subjects: subject: Pattern Formation and Solitons (nlin.PS)
subject: FOS: Physical sciences

description: We generalize the Kuramoto model by interpreting the $N$ variables on the unit circle as eigenvalues of a $N$-dimensional unitary matrix $U$, in three versions: general unitary, symmetric unitary and special orthogonal. The time evolution is generated by $N^2$ coupled differential equations for the matrix elements of $U$, and synchronization happens when $U$ evolves into a multiple of the identity. The Ott-Antonsen ansatz is related to the Poisson kernels that are so useful in quantum transport, and we prove it in the case of identical natural frequencies. When the coupling constant is a matrix, we find some surprising new dynamical behaviors.
Analisi delle segnalazioni di Incident Reporting inappropriate per categoria professionale: dove insistere con la formazione ..
Creators: name: Lai, Piero Luigi
Publisher: name: Journal of Preventive Medicine and Hygiene
Year: 2022

description: Author Correction In the version of this article originally published in The Journal of Preventive Medicine and Hygiene 2022;63:2S1:E211 https://doi.org/10.15167/2421‑4248/jpmh2022.63.2s1 there was an error at page E211. Read the errata in the text below or in ERRATA CORRIGE OPEN ACCESS J PREV MED HYG 2020; 62: E492 ERRATA CORRIGE J Prev Med Hyg 2022; 63 (suppl. 1): E1‐E443. https://doi.org/10.15167/2421‐4248/jpmh2022.63.2S1 page E211 Abstract Code: SIT16745-03 Analisi delle segnalazioni di Incident Reporting inappropriate per categoria professionale: dove insistere con la formazione C.L. GRAZIANI1, C. PETER1, C. LUCREZIA1, L. ARNOLDO2, S. DEGAN2, F. BELLOMO2, F. FARNETI2, R. COCCONI2 CORRIGE Analisi delle segnalazioni di Incident Reporting inappropriate per categoria professionale: dove insistere con la formazione C.L. GRAZIANI1, P. CAUTERO1, L. CHIANDETTI1, L. ARNOLDO2, S. DEGAN2, F. BELLOMO2, F. FARNETI2, R. COCCONI2
description: Journal of Preventive Medicine and Hygiene, Vol. 63 No. 3 (2022): 2022633
Stable broken $H^1$ and $\bf H(\mathrm{div})$ polynomial extensions for polynomial-degree-robust potential and flux reconstruction in three space dimensions
Creators: name: Ern, Alexandre
name: Vohralík, Martin
Publisher: name: arXiv
Year: 2017
Subjects: subject: Numerical Analysis (math.NA)
subject: FOS: Mathematics

description: We study extensions of piecewise polynomial data prescribed on faces and possibly in elements of a patch of simplices sharing a vertex. In the $H^1$ setting, we look for functions whose jumps across the faces are prescribed, whereas in the ${\bf H}(\mathrm{div})$ setting, the normal component jumps and the piecewise divergence are prescribed. We show stability in the sense that the minimizers over piecewise polynomial spaces of the same degree as the data are subordinate in the broken energy norm to the minimizers over the whole broken $H^1$ and ${\bf H}(\mathrm{div})$ spaces. Our proofs are constructive and yield constants independent of the polynomial degree. One particular application of these results is in a posteriori error analysis, where the present results justify polynomial-degree-robust efficiency of potential and flux reconstructions.
Neural Extended Kalman Filters for Learning and Predicting Dynamics of Structural Systems
Creators: name: Liu, Wei
name: Lai, Zhilu
name: Bacsa, Kiran
name: Chatzi, Eleni
Publisher: name: arXiv
Year: 2022
Subjects: subject: Machine Learning (cs.LG)
subject: Computational Engineering, Finance, and Science (cs.CE)
subject: Chaotic Dynamics (nlin.CD)
subject: Machine Learning (stat.ML)
subject: FOS: Computer and information sciences
subject: FOS: Physical sciences

description: Accurate structural response prediction forms a main driver for structural health monitoring and control applications. This often requires the proposed model to adequately capture the underlying dynamics of complex structural systems. In this work, we utilize a learnable Extended Kalman Filter (EKF), named the Neural Extended Kalman Filter (Neural EKF) throughout this paper, for learning the latent evolution dynamics of complex physical systems. The Neural EKF is a generalized version of the conventional EKF, where the modeling of process dynamics and sensory observations can be parameterized by neural networks, therefore learned by end-to-end training. The method is implemented under the variational inference framework with the EKF conducting inference from sensing measurements. Typically, conventional variational inference models are parameterized by neural networks independent of the latent dynamics models. This characteristic makes the inference and reconstruction accuracy weakly based on the dynamics models and renders the associated training inadequate. In this work, we show that the structure imposed by the Neural EKF is beneficial to the learning process. We demonstrate the efficacy of the framework on both simulated and real-world structural monitoring datasets, with the results indicating significant predictive capabilities of the proposed scheme.
description: Accepted for publication in Structural Health Monitoring
Performance of group testing algorithms with near-constant tests-per-item
Creators: name: Johnson, Oliver
name: Aldridge, Matthew
name: Scarlett, Jonathan
Publisher: name: arXiv
Year: 2016
Subjects: subject: Information Theory (cs.IT)
subject: Probability (math.PR)
subject: FOS: Computer and information sciences
subject: FOS: Mathematics

description: We consider the nonadaptive group testing with N items, of which $K = Θ(N^θ)$ are defective. We study a test design in which each item appears in nearly the same number of tests. For each item, we independently pick L tests uniformly at random with replacement, and place the item in those tests. We analyse the performance of these designs with simple and practical decoding algorithms in a range of sparsity regimes, and show that the performance is consistently improved in comparison with standard Bernoulli designs. We show that our new design requires 23% fewer tests than a Bernoulli design when paired with the simple decoding algorithms known as COMP and DD. This gives the best known nonadaptive group testing performance for $θ> 0.43$, and the best proven performance with a practical decoding algorithm for all $θ\in (0,1)$. We also give a converse result showing that the DD algorithm is optimal for these designs when $θ> 1/2$.
description: 16 pages, 2 figures. This work was presented in part at the 2016 IEEE International Symposium on Information Theory: arXiv:1602.03471
Power-law localization in one-dimensional systems with nonlinear disorder under fixed input conditions
Creators: name: Nguyen, Ba Phi
name: Kim, Kihong
Publisher: name: arXiv
Year: 2024
Subjects: subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: FOS: Physical sciences

description: We conduct a numerical investigation into wave propagation and localization in one-dimensional lattices subject to nonlinear disorder, focusing on cases with fixed input conditions. Utilizing a discrete nonlinear Schrödinger equation with Kerr-type nonlinearity and a random coefficient, we compute the averages and variances of the transmittance, $T$, and its logarithm, as functions of the system size $L$, while maintaining constant intensity for the incident wave. In cases of purely nonlinear disorder, we observe power-law localization characterized by $\langle T \rangle \propto L^{-γ_a}$ and $\langle \ln T \rangle \approx -γ_g \ln L$ for sufficiently large $L$. At low input intensities, a transition from exponential to power-law decay in $\langle T \rangle$ occurs as $L$ increases. The exponents $γ_a$ and $γ_g$ are nearly identical, converging to approximately 0.5 as the strength of the nonlinear disorder, $β$, increases. Additionally, the variance of $T$ decays according to a power law with an exponent close to 1, and the variance of $\ln T$ approaches a small constant as $L$ increases. These findings are consistent with an underlying log-normal distribution of $T$ and suggest that wave propagation behavior becomes nearly deterministic as the system size increases. When both linear and nonlinear disorders are present, we observe a transition from power-law to exponential decay in transmittance with increasing $L$ when the strength of linear disorder, $V$, is less than $β$. As $V$ increases, the region exhibiting power-law localization diminishes and eventually disappears when $V$ exceeds $β$, leading to standard Anderson localization.
description: 8 pages, 7 figures
Kähler groups and subdirect products of surface groups
Creators: name: Isenrich, Claudio Llosa
Publisher: name: arXiv
Year: 2017
Subjects: subject: Geometric Topology (math.GT)
subject: Algebraic Geometry (math.AG)
subject: Group Theory (math.GR)
subject: FOS: Mathematics
subject: 32J27, 20F65 (Primary), 32Q15, 20J05 (Secondary)

description: We present a construction that produces infinite classes of Kähler groups that arise as fundamental groups of fibres of maps to higher dimensional tori. Following the work of Delzant and Gromov, there is great interest in knowing which subgroups of direct products of surface groups are Kähler. We apply our construction to obtain new classes of irreducible, coabelian Kähler subgroups of direct products of $r$ surface groups. These cover the full range of possible finiteness properties of irreducible subgroups of direct products of $r$ surface groups: For any $r\geq 3$ and $2\leq k \leq r-1$, our classes of subgroups contain Kähler groups that have a classifying space with finite $k$-skeleton while not having a classifying space with finitely many $(k+1)$-cells. We also address the converse question of finding constraints on Kähler subdirect products of surface groups and, more generally, on homomorphisms from Kähler groups to direct products of surface groups. We show that if a Kähler subdirect product of $r$ surface groups admits a classifying space with finite $k$-skeleton for $k>\frac{r}{2}$, then it is virtually the kernel of an epimorphism from a direct product of surface groups onto a free abelian group of even rank.
description: 30 pages, V4: Some results were strengthened (in particular, Theorems 1.2 and 1.5 now include some additional consequences). Minor corrections and improvements to the exposition. Final accepted version, to appear in Geometry & Topology