We have investigated the weak antilocalization (WAL) in the pressurized Dirac semimetal $α$-(BEDT-TTF)$_2$I$_3$ across a correlation-driven quantum phase transition to a charge-ordered insulating state and evaluated the phase coherence length $L_ϕ$ and its temperature scaling under various pressures from the low-temperature magnetoconductivity. In the high-pressure regime, the system exhibits the conventional two-dimensional dephasing behavior ($L_ϕ \propto T^{-p}$ with $p \approx 1/2$), characteristic of electron-electron scattering in diffusive conductors. As the pressure approaches the critical pressure ($P_c \sim 1.2$ GPa), the temperature exponent is suppressed to $p \sim 0.3$, while $L_ϕ$ remains large ($700\text{-}800$ nm at 0.5 K). This anomalous scaling suggests nontrivial inelastic scattering associated with Dirac electrons near the quantum critical point. The persistence of WAL across the transition supports a gapless or nearly gapless quantum phase transition.

Electron transpiration cooling (ETC) can reduce aerothermal loads on sharp hypersonic leading edges, but its performance is governed by whether thermionically emitted electrons escape the hot surface or return as cathode-directed backflow. Here, a one-dimensional-in-space, three-dimensional-in-velocity electrostatic particle-in-cell/Monte Carlo collision model is developed for a full cathode--anode plasma diode, resolving thermionic emission, collisional plasma transport, emitted-electron backflow, and downstream collection. A helium benchmark is used to examine emitted-electron transport and backflow-limited current flow. With increasing imposed emission, the diode first remains in a weak-backflow regime, where net emitted-electron transport and downstream collection both increase with emission. Further increasing the emission produces a sharp transition to backflow-limited transport between $7.0\times10^{19}$ and $7.5\times10^{19},\mathrm{m^{-2},s^{-1}}$. At $7.25\times10^{19},\mathrm{m^{-2},s^{-1}}$, the backflow ratio reaches $54.03%$, while the net transport and downstream collection efficiencies fall to about $46%$. Above this transition, added backflow overcompensates the imposed emission increase, reducing useful emitted-electron transport rather than causing saturation. Boundary energy diagnostics show that stronger emission may still increase the nominal cathode-side cooling metric, but after transition this metric no longer indicates improved emitted-electron escape or full-gap transport. These results show that the present PIC-MCC framework captures the key kinetic processes governing ETC-relevant emitted-electron escape and backflow limitation.

The topological zeta function of a matroid is a rational function as well as a valuative invariant of the matroid, encoding rich combinatorial information. We analyze topological zeta functions of matroids from the vantage point of several matroid operations and operations on lattices of flats. We prove a clean recurrence relation for the Möbius inversion and use it to describe the topological zeta function of the truncation and free extension of a matroid in relation with that of the original matroid. We also characterize the Taylor coefficients of the topological zeta functions for matroids in terms of a matroid invariant, which we call the girth, and generalize an earlier result by Jensen-Kutler-Usatine.

The TCP/IP protocol stack uses IP addresses for two distinct roles: identifying hosts and locating their attachment points in the network topology. This dual purpose creates a fundamental tension that has led to routing and forwarding scalability challenges throughout the history of the Internet in unicast packet delivery and, more notably, in multicast delivery. This paper reviews the evolution of routing scalability solutions over the years and makes four observations. First, map-and-encap is a recurring architectural solution shared by all scalable unicast and multicast delivery methods, developed independently across different problem contexts. Second, a new solution tends to succeed when it can bring immediate local gains to early adopters without requiring coordination across administrative domains. Third, network routing and forwarding designs that depend on external factors, such as the number of distinct end sites or even application-specific deliveries, inherently preclude an upper bound on their scalability. Fourth, today's inter-domain routing protocol, BGP, lacks a topological abstraction equivalent to an egress router within a routing domain, thereby inherently preventing a map-and-encap solution for scalability. These observations offer insights into the design of future scalable routing system architectures.

Photoneutron double-differential cross sections in the giant dipole resonance (GDR) region were calculated to investigate the underlying nuclear reaction mechanisms, with particular emphasis on the role of the direct process. Contributions from direct, pre-equilibrium, and compound processes were all taken into account. Wilkinson's resonance direct (RD) theory, based on the independent particle model, was applied to describe high-energy neutron emission from the direct process. The angular distribution of neutrons emitted via the RD mechanism was formulated using the Agodi and Courant formalism, which was incorporated into the RD framework. Neutron emission from the pre-equilibrium and compound processes was calculated using the two-component exciton model and the Hauser-Feshbach formalism, respectively. The calculated results were compared with experimental data obtained at NewSUBARU using 16.6-MeV quasi-monochromatic linearly-polarized photon beams. Good agreement between calculations and measurements was observed for Pb, Au, and Sn, confirming the validity of the proposed model. Furthermore, the angular anisotropies of photoneutrons emitted from these elements were investigated, revealing considerable contributions from the RD process at high neutron energies. This study provides a deeper understanding of photoneutron emission mechanisms in the GDR energy region.

We study modified ruin probabilities in a Cramér-Lundberg model driven by a compound mixed Poisson process. In the heavy-tailed regime, if the integrated claim-size distribution is subexponential and the upper endpoint of the mixing distribution stays below the net-profit boundary, the modified and classical ruin probabilities are asymptotically equivalent. In the light-tailed regime, we prove a fixed-intensity ratio theorem and obtain both an endpoint-atom result and a sharp endpoint-density asymptotic with an explicit constant.

Generative artificial intelligence (AI) is reshaping higher education, yet many universities remain in early stages of adoption where AI innovation occurs informally and without institutional recognition. This paper presents a framework describing four levels of AI adoption in universities and illustrates these dynamics through a case study of AI-enabled curriculum initiatives in several units. We contend that the key institutional challenge is moving from isolated innovation to strategic integration, where universities redesign learning around AI-supported reasoning and align policies, workload models, and recognition systems to support educational transformation.

We resolve a longstanding open problem in the computational modeling of nonlinear plates by introducing a numerical method that exactly enforces the isometry constraint, namely, that the first fundamental form of the mid-surface coincides with the identity tensor. Several numerical methods have been proposed to approximate solutions of such manifold-constrained variational problems using gradient flows with tangent space updates. However, this class of methods presents two main challenges. First, a preprocessing step is required to enforce the boundary conditions and generate an initial guess sufficiently close to an isometry. Second, each step of the gradient flow typically increases the isometry defect. We adopt an alternative approach based on the proximal Galerkin framework, originally introduced for variational problems with convex inequality constraints. The resulting method preserves the geometric structure of the feasible set and yields an efficient algorithm in which each iterate is an exact isometry at the barycenter of every mesh cell. In contrast to existing methods, no preprocessing step is required, enabling broader applicability of this important category of mathematical models. Numerical experiments on standard benchmarks demonstrate that the method converges to a prescribed error tolerance in an asymptotically mesh-independent number of iterations and requires substantially fewer iterations than previous methods, even on coarse meshes.

This paper introduces the MAESTRO workflow, that enables the coupling of the PORTALS framework [P. Rodriguez-Fernandez et al, Nucl. Fusion 2024] with external solvers for the plasma equilibrium, pedestal physics, divertor constraints and heating. The surrogate-based optimization nature of the transport solver is ideally suited for external coupling, allowing efficient steady-state predictions of plasma profiles with full physics models. Improvements in the surrogate modeling of quasilinear transport models with PORTALS are presented, which enable the efficient handling of discontinuities in the transport fluxes that can arise from numerical issues or physical instabilities with extreme stiffness. The combination of physics-informed methods and advanced numerical techniques allows the MAESTRO workflow to provide accurate and efficient predictions of steady-state plasma profiles, which are critical for fusion reactor design and optimization.

In competitive resource allocation, a central coordinator may seek to gain an advantage not by directly controlling subordinate agents, but by strategically manipulating the information they receive. We study this problem within the framework of multi-player Tullock contests, where the coordinator influences subordinate players by designing their reported valuations of the contested prize, a mechanism that preserves the Tullock structure of the subordinates' objectives and thereby enables tractable equilibrium analysis. We first characterize the Nash equilibrium of the general multi-player Tullock contest, establishing how valuations and per-unit costs jointly determine equilibrium bids and payoffs. We then derive the optimal reported valuations for a coordinator managing two subordinates against a single opponent, and show that the structure of the optimal solution extends to contests with an arbitrary number of subordinates, reducing the coordinator's optimization to a two-variable problem regardless of system size.

We prove a fundamental change of measure theorem for the Brownian-time Brownian motion and its associated Brownian-time processes class introduced by Allouba and Zheng in 2001. This result, together with Allouba's prior work on (1) Brownian-time processes and their PDEs/SPDEs links and on (2) change of measure for SPDEs, is a critical building block in analyzing the behaviors of SDEs and SPDEs -- of different types and orders -- driven by Brownian-time noises and their relatives.

We consider a system of elliptic equations, depending on a small parameter $\eps$, that models long-range segregation of populations. The diffusion is governed by the Laplacian. This system was previously investigated by Caffarelli, Patrizi, and Quitalo in \cite{CL2} as a model in population dynamics, and they established the regularity of the free boundary in two dimensions. In this paper we study the free boundary in the higher dimensional case. We extend the concept of angles and asymptotic cones to higher dimensions, and give a characterization of regular and singular points in terms of their densities and angles. We obtain a structure result of the free boundary and show that, if the angles at the singular points are away from $\frac{nω_n}{2}$, the regular set is open in the free boundary and locally a $C^1$ manifold of dimension $n-1$. We also show that, if the supports of the populations are convex, they are convex polytopes. A weak form of the equality of angles for the convex configuration is also derived.

A central challenge in the origin of life is understanding how catalytic peptide-like polymers and information-bearing nucleic acid-like polymers emerged as an interde-pendent system. This study constructs a primordial cognitive model incorporating two internal Lotka-Volterra chemical oscillators to investigate, through simulation, whether a catalytic loop, primordial tRNAs, and nucleic acids that record and amplify them, can form through the interaction of polymers represented by binary (0/1) sequences. In this model, a mechanism was introduced where the synthesis of internal oscillations pro-vides a temporal bias for 0/1 selection during polymer elongation, while generated functional sequences are protected, recorded, and re-amplified. Simulation results demonstrated that the proposed cognitive model significantly outperformed a contrast model based on random 0/1 selection in terms of the establishment rate of catalytic loops, the accumulation of functional molecules, polymer elongation, and the reduction of Shannon entropy in sequence distribution. Furthermore, this superiority was generally maintained across sensitivity analyses, including batch calculations with different ran-dom seeds. While this study is a computational model based on abstract binary se-quences and simplified translation/replication rules rather than a direct reconstruction of life's origin, it provides a working hypothesis for the interdependent emergence of catalytic function and information retention by demonstrating that internal oscillations can bias sequence exploration within a framework linking autocatalytic networks, re-cording, and group selection. Future research must verify the generality and empirical validity of this framework by expanding monomer types, evolving into multi-oscillator systems, and establishing correspondences with compartmentalized experimental sys-tems.

We present an exact analytic study of unitary coherence dynamics in a minimal two qubit superconducting system. By deriving the full time evolution operator and propagating Bell state initial conditions, we obtain closed form time dependent pure state density matrices and an explicit analytic expression for the $C_{l_1}$ norm of coherence. Two of the Bell states are shown to be invariant under the model dynamics with constant coherence, while the other two exhibit controlled, parameter dependent coherence oscillations. The oscillatory behaviour is governed by two distinct frequency scales that map directly onto the circuit coupling and tunnelling parameters, allowing predictable tuning of amplitude and periodicity. Numerical visualizations clarify operating regimes for transient enhancement or suppression of coherence. These results deliver compact, analytically tractable tools for parameter optimisation and provide a clear foundation for incorporating dissipation and for experimental validation.

A DFA $\mathcal{A}$ is composite if there exist DFAs $\mathcal{A}_1,\dots,\mathcal{A}_t$ with $\mathcal{L}(\mathcal{A}) = \bigcap_{i=1}^{t} \mathcal{L}(\mathcal{A}_i)$ such that each $\mathcal{A}_i$ has strictly less states than the minimal DFA deciding $\mathcal{L}(\mathcal{A})$. Otherwise, it is prime. Prime-DFA is the problem of deciding primality for a given DFA. It was defined by Kupferman and Mosheiff in 2015 and it was shown to be NL-hard and in ExpSpace. This paper proves the NP-hardness of Prime-DFA, thereby making the first progress in closing this doubly-exponential gap. It proves the NP-hardness by a reduction from the propositional logic satisfiability problem. The correctness of the reduction relies on an involved characterization of primality for a class of DFAs which contains those that can occur in the reduction.

Shape-morphing metamaterials enable adaptive structures capable of complex functional deformations, with applications ranging from reconfigurable structures and soft robotics to medical devices. However, their design remains challenging due to an inherent trade-off between deformation programmability and computational scalability. Periodic architectures offer computational tractability but are limited in their programmability, whereas aperiodic metamaterials provide richer deformation spaces at the cost of substantially increased design complexity. To bridge this gap, we propose a scalable active metamaterial (SAM) design framework that decouples the design problem into two scales by exploiting the local deformation independence of units isolated by stiff structural members. At the macroscale, global shape deformation is determined by iteratively solving a constrained mesh optimization problem incorporating data-driven constraints. At the microscale, the local infill geometry is obtained through inverse design via either a conditional diffusion model or an adjustable search strategy. This hierarchical decomposition enables fast, accurate, and scalable design of aperiodic shape-morphing metamaterials, offering a new computational paradigm for the design of programmable material systems.

The study of cultural evolution seeks to understand the processes by which behavioral variants are chosen in cultures over time, often as the result of large numbers of individual human choices. The selection of new popes, each of whom chooses a papal name -- typically reusing previous names in reference to previous popes -- is among the longest ongoing cultural processes taking place in a single human institution. Here, we use the record of papal names as a setting for long-term analysis of human cultural behavior. Although papal name choices are careful individual decisions, we find that the long-term sequence of papal names accords with predictions of a family of models developed in population genetics and stochastic processes -- Ewens sampling theory and the Chinese restaurant process -- which in the case of papal names amounts to randomly copying an existing name in proportion to its frequency, with the possibility of innovation of new names (mutations). Hence, despite the consideration that enters into choices of individual papal names, aggregate cultural behavior in a 2000-year old human process can potentially be described with simple laws. We discuss instances in which particular historical events might have caused temporary deviations from the random-copying model.

Gravitational-wave observations have renewed interest in the black-hole mass gap and in the maximum mass of first-generation black holes below its lower edge. The \(^{12}{\rm C}(α,γ)^{16}{\rm O}\) reaction plays a central role in this problem because it determines the carbon-to-oxygen ratio after core-helium burning and thereby affects the later evolution of massive stars toward pulsational pair instability and pair-instability supernovae. Recent attempts to constrain \(S(300~{\rm keV})\) from gravitational-wave population inferences face important limitations, because the lower edge of the black-hole mass gap is not directly measured. It is inferred model dependently from assumptions about stellar evolution, metallicity, mass loss, rotation, binary evolution, hierarchical mergers, selection effects, priors, and the adopted population model. Therefore, values of \(S(300~{\rm keV})\) inferred from black-hole populations must remain consistent with independent nuclear-physics constraints. In this work we reanalyze the low-energy \(^{12}{\rm C}(α,γ)^{16}{\rm O}\) \(S\) factor using updated information on the subthreshold \(1^{-}\) and \(2^{+}\) ANCs and on the ground-state ANC of \(^{16}{\rm O}\), together with direct capture data. These constraints favor a lower \(S(300~{\rm keV})\) than the older central evaluation and disfavor very large values required by some black-hole-population interpretations. Using the resulting ANC-constrained \(S(300~{\rm keV})\) range and the transformed relation between this quantity and the lower edge of the pair-instability mass gap, we estimate \[ \frac{M_{\rm BH}}{M_\odot}\simeq 61\text{--}75 . \] Thus, the present nuclear-physics constraints favor a relatively high lower edge of the first-generation black-hole mass gap.

We present a comprehensive analysis of extended H$_2$ emission from 34 protoplanetary disks observed with the JWST Disk Infrared Spectroscopic Chemistry Survey (JDISCS), supplemented by archival data. We investigated the morphology, kinematics, excitation conditions, and mass dynamics of H$_2$. Extended emission from pure rotational H$_2$ lines is found to be common, with 16 sources exhibiting clear signatures of disk winds. These include monopolar and bipolar structures in inclined disks and ring-like or bubble-like morphologies in face-on systems features indicative of wide-angle disk winds. Our analysis shows that the H$_2$ is consistent with slow {(4.2$^{+6.7}_{-3.0}$ km s$^{-1}$)} MHD driven winds. For ten disks, we model the wind morphology and find a median half-opening angle of $45\arcdeg^{+5}_{-4}$ and a characteristic power-law index of $α\sim$ 1.6. Excitation analysis yields a median gas temperature of 624 $\pm$ 130 K and a column density of $\log(N_{\mathrm{tot}}\,[\mathrm{cm}^{-2}]) = 18.6 \pm 0.6$. The median wind mass-loss rate, ${\rm log_{10}}(\dot{\rm M}_{\rm wind}^{\rm tot}) = -9_{-0.4}^{+0.8}\,{\rm M_\odot\,yr^{-1}}$, implies that, if molecular winds are the dominant mechanism responsible for disk dispersal, a typical disk with a mass of $2-3\,M_{\rm Jup}$ would dissipate on a $\sim$2-3 Myr timescale, consistent with observed disk lifetimes. The $\dot{\rm M}_{\mathrm{\rm wind}}^{\rm tot}$ span a relatively narrow range ($\sim$2 dex) and do not correlate strongly with accretion rates onto the star, suggesting that the mass loss rate and the accretion rates are probing different timescales. Our findings demonstrate that spatially extended warm H$_2$ emission is a widespread and reliable tracer of molecular disk winds in protoplanetary systems.

We consider pairs of maps $(f,g)$, where $f$ is an $n$-valued map and $g$ is an $m$-valued map, defined on connected finite polyhedra. A point $x$ such that $f(x)\cap g(x)\neq \emptyset$ is called a coincidence point of $f$ and $g$. A useful device for studying coincidence points would be a Nielsen-type invariant which provides a lower bound for the number of coincidence points of all $(n, m)$-valued pairs of maps homotopic to $(f,g)$. The construction of such an invariant $N(f:g)$ was proposed in [J. Fixed Point Theory Appl. 14, 309--324 (2013)]. Unfortunately, this approach has some flaws. In this paper, we present a modified construction that yields a corrected form of the invariant, defined in terms of the intersection points of the graphs of $f$ and $g$. In the case of $(n, m)$-valued pairs of maps of the circle our invariant provides a sharp lower bound, which we precisely determine.

Current approaches to addressing deceptive design largely focus on visible interface manipulations, commonly referred to as "dark patterns". With the rise of generative AI, deception is becoming more difficult to spot and easier to live with, as it is quietly embedded in default settings, automated suggestions, and conversational interactions rather than discrete interface elements. These subtle, normalised forms of influence, which Simone Natale frames as "banal deception", shape everyday digital use and blur the line between AI-enabled assistance and manipulation. This position paper explores banality as a lens through which to reason through deception in generative AI experiences, especially with chatbots. We explore what Natale describes as users' own involvement in their deception, and argue that this perspective could lead to future work for introducing friction to safeguard users from deception in generative AI interactions, such as empowering users through raising awareness, providing them with intervention tools, and regulatory or enforcement improvements. We present these concepts as points for discussion for the deceptive design scholarly community.

In this note, we prove that for any abelian variety defined over $\overline{\mathbb{Q}}$, its de Rham-Betti (dRB) group necessarily contains $\mathbb{G}_{m}$ as the group of homotheties. Consequently, this rules out the existence of non-zero dRB classes in odd-degree cohomology groups of abelian varieties over $\overline{\mathbb{Q}}$. This generalises results of the first part of arXiv:2511.01072.

The monolithic nature of widely used commodity operating systems means that vulnerabilities in one software component potentially compromise the entire kernel. Formally verifying these systems, or redesigning them altogether as microkernels, according to the principle of least privilege, requires significant effort. Researchers have therefore considered compartmentalization techniques that minimize or totally avoid changes to existing systems. However, current approaches use techniques such as Memory Protection Keys (MPKs), necessitating extensive code analysis to ensure security, or use virtualization by instrumenting the kernel with calls to the glue code that switches compartments. In this work, we present Pomegranate, a framework that uses hardware-assisted virtualization to securely compartmentalize an existing system with minimal to no modifications to its source code. Allowed interactions between compartments are defined using an access-control policy and strictly enforced using Extended Page Tables. Using special sentry functions, Pomegranate is able to check all cross-compartment transitions without trapping into the hypervisor. We demonstrate the efficacy of Pomegranate on a compartmentalized Linux network stack using the igc NIC driver. Experiments show the overheads of our approach are negligible at MTU-sized packets when compartment boundaries are carefully established to avoid excessive inter-compartment communication.

Our understanding of cell division control in bacteria still relies largely on interpreting correlations between phenomenological variables, with limited connection to the underlying molecular mechanisms. Here, we analytically solve a stochastic threshold-accumulation model in which a size-dependent divisor protein triggers division upon reaching a noisy, autocorrelated threshold, quantifying within a unified framework the combined effects of intrinsic and extrinsic noise and key mechanistic parameters such as protein reset and threshold memory. We show that incorporating these elements yields behavior far richer than the commonly assumed adder, spanning a continuum of division strategies from timer to sizer while modulating size fluctuations in a nontrivial fashion. Comparison with single-cell E. coli data shows that extrinsic noise and additional mechanistic ingredients are required to account for the observed size fluctuations. The adder emerges when threshold correlations balance protein reset, generalizing the hypothesis that full reset is necessary to maintain adder control. Our results establish a unified analytical framework linking stochastic molecular processes to emergent division laws, to be used in more complex bacterial cell-cycle models.

These lecture notes cover the theory of convex optimization, with a particular emphasis on first-order methods.

Let $R$ be a commutative Noetherian local ring. We prove a variety of new formulae for modules of finite quasi-projective or finite quasi-injective dimension. These include the Derived Depth Formula, itself an extension of Auslander famous depth formula, a variation of the Derived Depth Formula for width, an extended version of Ischebeck's Formula, and a Dependency formula in the vein of Jorgensen. Several special cases of our main results are new even under stronger assumptions on the vanishing of various complete intersection dimensions.

We show the existence of a set $S\subset\mathbb{Z}^2$ avoiding collinear triples satisfying $|S\cap [n]^2|=Ω(n/\sqrt{\log n})$ for sufficiently large $n$. This improves on the best-known lower bound on Erde's extensible no-three-in-line problem due to Nagy, Nagy and Woodroofe by $\sqrt{\log n}$, leaving the same gap to the trivial upper bound. Our construction is random.

YouTube is central to contemporary mass media. However, the official YouTube API does not provide access to the full set of creators or creator metadata on the platform. This lack of basic visibility into the YouTube ecosystem hinders understanding of the platform's creator economy. Researchers currently have no easy, transparent, or replicable way to construct large-scale datasets of YouTube creators and their audiences over time. This makes it challenging to study vital social questions, such as how changes to the YouTube recommendation algorithm shape creator incentives and by extension the mass media on the platform. We address this gap with TubeCensus, a large-scale longitudinal dataset of YouTube creators and subscriber counts, constructed by collecting, linking, and organizing nearly two decades of YouTube page captures from the Internet Archive. This approach is transparent and replicable and does not require interaction with the YouTube API, whose output can change over time. We validate the coverage of TubeCensus against prior estimates of YouTube's size and find that our resource includes creators responsible for at least 30-36% of all YouTube content. We also find that TubeCensus provides good coverage of prominent creators. To support future research, we hide the substantial complexities of the YouTube identifier system and Internet Archive capture system by distributing our dataset via an easy-to-use pip package. Finally, we use our resource to complete basic exploratory analysis of YouTube channel content and the mechanisms associated with YouTube channel growth.

The most impressively prolific exploration of superstring models (aiming for our physical reality) has been focused on worldsheet-supersymmetric gauged linear sigma models and the closely associated complex-algebraic toric geometry. Mirror duality relates this to the inherently real symplectic geometry of Calabi-Yau factors in spacetime, implying a need for a more general, heterotic framework of analysis. In turn, a closer look at possible deformations even amongst the complex-algebraic complete intersections and toric geometry models themselves indicates an a priori non-algebraic type of generalization that however perfectly aligns with requirements of mirror duality.

We apply a previously developed method of renormalon-based resummation of spacelike and timelike QCD observables, to evaluate of the values of the pole masses $m_q$ of $q=b$ and $c$ quarks, using as input the knowledge of the values of the corresponding ${\overline{\rm MS}}$ masses ${\overline m}_q \equiv {\overline m}_q({\overline m}_q^2)$. The evaluation also uses the knowledge of the first few coefficients of the perturbation expansion of $m_q$ (i.e., of $m_q/{\overline m}_q$), as well as the known renormalon structure of that expansion. In the evaluation, we use the timelike QCD running coupling based on a specific holomorphic spacelike QCD coupling, in order to avoid additional ambiguities due to the Landau poles of the usual perturbative coupling. The principal IR regulator parameter of the coupling is varied in an expected range. We also reevaluate the chromomagnetic Wilson coefficient of heavy quark ${\hat C}(m_q^2)$, and extract values of several corresponding hadronic parameters.