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In the present work, we consider a fractional p-Kirchhoff equation in the entire space R^N featuring doubly nonlinearities, involving a generalized nonlocal Choquard subcritical term together with a local critical Sobolev term; the problem also includes a Hardy-type term; additionaly, all terms have critical singular weights. Our result improve upon previous work in the following ways: we focus our attention on the existence of a nontrivial weak solution for fractional p-Kirchhoff equation in the entire space R^N. The possibility of a slower growth in the nonlinearity makes it more difficult to establish a compactness condition; to do so, we use the Cerami condition. The crucial points in our argument are the uniform boundedness of the convolution part and the lack of compactness of the Sobolev embeddings., Comment: 25 pages

Although digital methods have significantly advanced morphology, practitioners are still challenged to understand and process tomographic specimen data. As automated processing of fossil data remains insufficient, morphologists still engage in intensive manual work to prepare digital fossils for research objectives. We present an open-source tool that enables morphologists to explore tomographic data similarly to the physical workflows that traditional fossil preparators experience in the field. We assessed the usability of our prototype for virtual fossil preparation and its accompanying tasks in the digital preparation workflow. Our findings indicate that integrating haptics into the virtual preparation workflow enhances the understanding of the morphology and material properties of working specimens. Our design's visuohaptic sculpting of fossil volumes was deemed straightforward and an improvement over current tomographic data processing methods., Comment: Accepted at KUI 2024

Given an $r$-colouring of the edges of a graph $G$, we say that it can be partitioned into $p$ monochromatic cycles when there exists a set of $p$ vertex-disjoint monochromatic cycles covering all the vertices of $G$. In the literature of this problem, an edge and a single vertex both count as a cycle. We show that for every $2$-colouring of the edges of a complete balanced bipartite graph, $K_{n,n}$, it can be partitioned into at most 4 monochromatic cycles. This type of question was first studied in 1970 for complete graphs and in 1983, by Gy\'arf\'as and Lehel, for $K_{n,n}$. In 2014, Pokrovskiy, has showed that any $2$-colouring of the edges of $K_{n,n}$ can be partitioned into at most $3$ paths. It turns out that finding monochromatic cycles instead of paths is a natural question that has also being asked for other graphs. In 2015, Schaudt and Stein have showed that at most 14 cycles are necessary., Comment: 17 pages, 21 figures

From the proliferative mechanisms generating neurons from progenitor cells to neuron migration and synaptic connection formation, several vicissitudes culminate in the mature brain. Both component loss and gain remain ubiquitous during brain development. For example, rodent brains lose over half of their initial neurons and synapses during healthy development. The role of deleterious steps in network ontogeny remains unclear, yet it is unlikely these costly processes are random. Like neurogenesis and synaptogenesis, synaptic pruning and neuron death likely evolved to support complex, efficient computations. In order to incorporate both component loss and gain in describing neuronal networks, we propose an algorithm where a directed network evolves through the selective deletion of less-connected nodes (neurons) and edges (synapses). Resulting in networks that display scale-invariant degree distributions, provided the network is predominantly feed-forward. Scale-invariance offers several advantages in biological networks: scalability, resistance to random deletions, and strong connectivity with parsimonious wiring. Whilst our algorithm is not intended to be a realistic model of neuronal network formation, our results suggest selective deletion is an adaptive mechanism contributing to more stable and efficient networks. This process aligns with observed decreasing pruning rates in animal studies, resulting in higher synapse preservation. Our overall findings have broader implications for network science. Scale-invariance in degree distributions was demonstrated in growing preferential attachment networks and observed empirically. Our preferential detachment algorithm offers an alternative mechanism for generating such networks, suggesting that both mechanisms may be part of a broader class of algorithms resulting in scale-free networks.

We unravel the Rodeo Algorithm to determine the eigenstates and eigenvalues spectrum for a general Hamiltonian considering arbitrary initial states. By presenting a novel methodology, we detail the original method and show how to define all properties without having prior knowledge regarding the eigenstates. To this end, we exploit Pennylane and Qiskit platforms resources to analyze scenarios where the Hamiltonians are described by the Zeeman model for one and two spins. We also introduce strategies and techniques to improve the algorithm's performance by adjusting its intrinsic parameters and reducing the fluctuations inherent to data distribution. First, we explore the dynamics of a single qubit on Xanadu simulators to set the parameters that optimize the method performance and select the best strategies to execute the algorithm. On the sequence, we extend the methodology for bipartite systems to discuss how the algorithm works when degeneracy and entanglement are taken into account. Finally, we compare the predictions with the results obtained on a real superconducting device provided by the IBM Q Experience program, establishing the conditions to increase the protocol efficiency for multi-qubit systems.

A tracer sample in a gravitational potential, starting from a generic initial condition, phase-mixes towards a stationary state. This evolution is accompanied by an entropy increase, and the final state is characterized by a distribution function (DF) that depends only on integrals of motion (Jeans theorem). We present a method to constrain a gravitational potential where a sample is stationary by minimizing the entropy the sample would have if it were allowed to phase-mix in trial potentials. This method avoids assuming a known DF, and is applicable to any sets of integrals. We provide expressions for the entropy of DFs depending on energy, $f(E)$, energy and angular momentum, $f(E,L)$, or three actions, $f(\vec{J})$, and investigate the bias and fluctuations in their estimates. We show that the method correctly recovers the potential parameters for spherical and axisymmetric models. We also present a methodology to characterize the posterior probability distribution of the parameters with an Approximate Bayesian Computation, indicating a pathway for application to observational data. Using $N=10^4$ tracers with $20\%$-uncertainties in the 6D coordinates, we recover the flattening parameter $q$ of an axisymmetric potential with $\sigma_q/q\sim 10\%$., Comment: Significant changes in appendix with mathematical results. Final expressions and numerical results are the same. A couple of discussions subsections added, and a new appendix on the possibility of maximizing an entropy in angle-space. Submitted to ApJ

Although Virtual Reality (VR) has undoubtedly improved human interaction with 3D data, users still face difficulties retaining important details of complex digital objects in preparation for physical tasks. To address this issue, we evaluated the potential of visuohaptic integration to improve the memorability of virtual objects in immersive visualizations. In a user study (N=20), participants performed a delayed match-to-sample task where they memorized stimuli of visual, haptic, or visuohaptic encoding conditions. We assessed performance differences between these encoding modalities through error rates and response times. We found that visuohaptic encoding significantly improved memorization accuracy compared to unimodal visual and haptic conditions. Our analysis indicates that integrating haptics into immersive visualizations enhances the memorability of digital objects. We discuss its implications for the optimal encoding design in VR applications that assist professionals who need to memorize and recall virtual objects in their daily work.

The operation of the next generation of gamma-ray observatories will lead to a great advance in dark matter searches. In this paper, we use the hidden sectors hypothesis within the so-called secluded models to calculate the capabilities of the Southern Wide-field Gamma-ray Observatory (SWGO) to detect gamma-ray signatures produced by dark matter particles concentrated in the Sun. We assume the dark matter particle annihilates into metastable mediators which decay into $\gamma\gamma$, $e^+e^-$, $\tau^+\tau^-$, and $\bar{b}b$ outside the Sun. We found that the SWGO will be able to probe a spin-dependent cross-section of about $10^{-46}$ cm$^2$ for dark matter masses smaller than 5 TeV. This result shows an unprecedented sensitivity surpassing the current instruments by more than one order of magnitude., Comment: 15 pages, 3 figures

Programmable materials are desirable for a variety of functional applications that range from biomedical devices, actuators and soft robots to adaptive surfaces and deployable structures. However, current smart materials are often designed to respond to single stimuli (like temperature, humidity, or light). Here, a novel multi-stimuli-responsive composite is fabricated using direct ink writing (DIW) to enable programmability in both space and time and computation of logic operations. The composite hydrogels consist of double-network matrices of poly(N-isopropylacrylamide) (PNIPAM) or poly(acrylic acid) (PAA) and sodium alginate (SA) and are reinforced by a high content of cellulose nanocrystals (CNC) (14 wt%) and nanofibers (CNF) (1 wt%). These composites exhibit a simultaneously tunable response to external stimuli, such as temperature, pH, and ion concentration, enabling precise control over their swelling and shrinking behavior, shape, and mechanical properties over time. Bilayer hydrogel actuators are designed to display bidirectional bending in response to various stimuli scenarios. Finally, to leverage the multi-responsiveness and programmability of this new composite, Boolean algebra concepts are used to design and execute NOT, YES, OR, and AND logic gates, paving the way for self-actuating materials with embodied logic.

Virtual humans (i.e., embodied conversational agents) have the potential to support college students' mental health, particularly in Science, Technology, Engineering, and Mathematics (STEM) fields where students are at a heightened risk of mental disorders such as anxiety and depression. A comprehensive understanding of students, considering their cultural characteristics, experiences, and expectations, is crucial for creating timely and effective virtual human interventions. To this end, we conducted a user study with 481 computer science students from a major university in North America, exploring how they co-designed virtual humans to support mental health conversations for students similar to them. Our findings suggest that computer science students who engage in co-design processes of virtual humans tend to create agents that closely resemble them demographically--agent-designer demographic similarity. Key factors influencing virtual human design included age, gender, ethnicity, and the matching between appearance and voice. We also observed that the demographic characteristics of virtual human designers, especially ethnicity and gender, tend to be associated with those of the virtual humans they designed. Finally, we provide insights concerning the impact of user-designer demographic similarity in virtual humans' effectiveness in promoting mental health conversations when designers' characteristics are shared explicitly or implicitly. Understanding how virtual humans' characteristics serve users' experiences in mental wellness conversations and the similarity-attraction effects between agents, users, and designers may help tailor virtual humans' design to enhance their acceptance and increase their counseling effectiveness., Comment: 43 pages, 12 figures, revision after acceptance with minor revisions at ACM Transactions on Applied Perception

Impulsive dynamical systems, modeled by a continuous semiflow and an impulse function, may be discontinuous and may have non-intuitive topological properties, as the non-invariance of the non-wandering set or the non-existence of invariant probability measures. In this paper we study dynamical features of impulsive flows parameterized by the space of impulses. We prove that impulsive semiflows determined by a C1-Baire generic impulse are such that the set of hyperbolic periodic orbits is dense in the set of non-wandering points which meet the impulsive region. As a consequence, we provide sufficient conditions for the non-wandering set of a typical impulsive semiflow (except the discontinuity set) to be invariant. Several applications are given concerning impulsive semiflows obtained from billiard, Anosov and geometric Lorenz flows.

Current blockchains do not provide any security guarantees to the smart contracts and their users as far as the content of the transactions is concerned. In the spirit of decentralization and censorship resistance, they follow the paradigm of including valid transactions in blocks without any further scrutiny. Rollups are a special kind of blockchains whose primary purpose is to scale the transaction throughput. Many of the existing rollups operate through a centrally operated sequencing protocol. In this paper, we introduce the Sequencer Level Security (SLS) protocol, an enhancement to sequencing protocols of rollups. This pioneering contribution explores the concept of the sequencer's capability to identify and temporarily quarantine malicious transactions instead of including them in blocks immediately. We describe the mechanics of the protocol for both the transactions submitted to the rollup mempool, as well as transactions originating from Layer one. We comment on topics such as trust and decentralization, and consider the security impact on the protocol itself. We implement a prototype of the SLS protocol, Zircuit, which is built on top of Geth and the OP stack. The SLS protocol described can be easily generalized to other rollup designs, and can be used for purposes other than security.

Quantum interactions exchanging different types of particles play a pivotal r\^{o}le in quantum many-body theory, but they are not sufficiently investigated from a mathematical perspective. Here, we consider a system made of two fermions and one boson, in order to study the effect of such an off-diagonal interaction term, having in mind the physics of cuprate superconductors. Additionally, our model also includes a generalized Hubbard interaction (i.e., a general local repulsion term for the fermions). Regarding pairing, exponentially localized dressed bound fermion pairs are shown to exist and their effective dispersion relation is studied in detail. Scattering properties of the system are derived for two channels: the unbound and bound pair channels. We give particular attention to the regime of very large on-site (Hubbard) repulsions, because this situation is relevant for cuprate superconductors.

This study presents photometric solutions for a carefully selected sample of 181 detached eclipsing binary systems recently observed by the Transiting Exoplanet Survey Satellite (TESS) mission. Our findings contribute to discussions about OBA-type systems and the orbital circularization influenced by tidal interactions. The results encompass crucial parameters, including the sum of radii fraction ($r_{\rm a}\,+\,r_{\rm b}$), radii ratio ($k$), orbital inclination ($i$), surface brightness ratio ($J$), and combinations of the longitude of the periastron and orbital eccentricity ($e\,\sin\,\omega$ and $e\,\cos\,\omega$). Geometric light curve fitting is performed using version 43 of the {\sc jktebop} code, serving as the primary tool for determining orbital elements and physical ratios. Careful uncertainty estimates for these findings are derived through bootstrap simulations. This work introduces unprecedented photometric solutions for 172 well-detached eclipsing systems, while the results for the remaining nine systems exhibit excellent agreement with those previously reported in the literature. Additionally, a critical primary radius fraction ($R_{\rm a}/a$) of 0.266 is identified for our sample of radiative envelope stars, consistent with observational and theoretical findings in the literature. Finally, we determine a circularization period of 5.762 days based on a function from the literature, revealing a discrepancy with Zahn's theory for hot stars., Comment: When we updated our paper, errors emerged in the figures due to JKTEBOP's limitations with our data. We chose the PHOEBE code, revealing significant discrepancies in results. JKTEBOP's susceptibility to noise also undermines result validity. Thus, we withdrawn the work, recognizing JKTEBOP's inadequacy in our data. Consequently, we have decided to discontinue this line of investigation

This paper analyzes the redistributive impacts of indirect taxation reforms in Brazil inspired by PEC 45/2019, particularly in the version that led to EC 132/2023. Comparisons are made between the current system and the simulated reforms, considering the distribution of the tax burden among families in different income classes, as well as the impact on poverty and inequality indicators. The simulations are conducted based on the combination of effective tax rates that apply to goods and services consumed by households, using nationally representative microdata from family budgets., Comment: in Portuguese language

Interactive narratives offer a novel approach to presenting business process models, making them more accessible and collaborative. These narratives create a hyper-textual environment that facilitates knowledge exchange and comprehension for ordinary individuals. However, designing such narratives is complex, as business process modelers must accurately identify and translate the graphic elements of a process model into dynamic narrative elements. This research paper introduces the Scripting Your Process (SYP) method, which provides a systematic approach to designing interactive narratives based on business process models. Following the principles of Design Science Research (DSR), a quasi-experimental study demonstrates and evaluates the SYP method. The results show that the SYP method successfully achieves its objective, contributing to the systematic design of interactive narratives derived from business process models. Consequently, individuals who are not experts in business process management can understand these processes in an engaging and gameful manner., Comment: 18 pages. Obs.: This paper has already been accepted in the International Journal of Business Information Systems (IJBIS) and it is in the journal publication schedule. This paper is the \underline{Author's Original and personal} version

Monochromatic gamma-ray signals constitute a potential smoking gun signature for annihilating or decaying dark matter particles that could relatively easily be distinguished from astrophysical or instrumental backgrounds. We provide an updated assessment of the sensitivity of the Cherenkov Telescope Array (CTA) to such signals, based on observations of the Galactic centre region as well as of selected dwarf spheroidal galaxies. We find that current limits and detection prospects for dark matter masses above 300 GeV will be significantly improved, by up to an order of magnitude in the multi-TeV range. This demonstrates that CTA will set a new standard for gamma-ray astronomy also in this respect, as the world's largest and most sensitive high-energy gamma-ray observatory, in particular due to its exquisite energy resolution at TeV energies and the adopted observational strategy focussing on regions with large dark matter densities. Throughout our analysis, we use up-to-date instrument response functions, and we thoroughly model the effect of instrumental systematic uncertainties in our statistical treatment. We further present results for other potential signatures with sharp spectral features, e.g.~box-shaped spectra, that would likewise very clearly point to a particle dark matter origin., Comment: 44 pages JCAP style (excluding author list and references), 19 figures; minor changes to match published version

We report the first experimental demonstration of the replica symmetry breaking (RSB) phenomenon in a fiber laser system supporting standard mode-locking (SML) regime. Though theoretically predicted, this photonic glassy phase remained experimentally undisclosed so far. We employ an ytterbium-based mode-locked fiber laser with a very rich phase diagram. Two phase transitions are observed separating three different regimes: cw, quasi-mode-locking (QML), and SML. The regimes are intrinsically related to the distinct dynamics of intensity fluctuations in the laser spectra. We set the connection between the RSB glassy phase with frustrated modes and onset of L-shaped intensity distributions in the QML regime, which impact directly the replica overlap measure., Comment: 17 pages, 12 figures, 1 Supplementary material