Recent Results Research Articles

Further remarks on absorbing Markov decision processes

In this note, based on the recent remarkable results of Dufour and Prieto-Rumeau, we deduce that for an absorbing Markov decision process with a given initial state, under a standard compactness-continuity condition, the space of occupation measures has the same convergent sequences, when it is endowed with the weak topology and with the weak-strong topology. We provided two examples demonstrating that imposed condition cannot be replaced with its popular alternative, and the above assertion does not hold for the space of marginals of occupation measures on the state space. Moreover, the examples also clarify some results in the previous literature.

Lectin-Based Approaches to Analyze the Role of Glycans and Their Clinical Application in Disease.

Lectin-based approaches remain a valuable tool for analyzing glycosylation, especially when detecting cancer-related changes. Certain glycans function as platforms for cell communication, signal transduction, and adhesion. Therefore, the functions of glycans are important considerations for clinical aspects, such as cancer, infection, and immunity. Considering that the three-dimensional structure and multivalency of glycans are important factors for their function, their binding characteristics toward lectins provide vital information. Glycans and lectins are inextricably linked, and studies on lectins have also led to research on the roles of glycans. The applications of lectins are not limited to analysis but can also be used as drug delivery tools. Moreover, mammalian lectins are potential therapeutic targets because certain lectins change their expression in cancer, and lectin regulation subsequently regulates several molecules with glycans. Herein, we review lectin-based approaches for analyzing the role of glycans and their clinical applications in diseases, as well as our recent results.

Advancing Cholangiocarcinoma Care: Insights and Innovations in T Cell Therapy.

Cholangiocarcinoma (CCA) is a rare and aggressive malignancy originating from the bile ducts, with poor prognosis and limited treatment options. Traditional therapies, such as surgery, chemotherapy, and radiation, have shown limited efficacy, especially in advanced cases. Recent advancements in immunotherapy, particularly T cell-based therapies like chimeric antigen receptor T (CAR T) cells, tumor-infiltrating lymphocytes (TILs), and T cell receptor (TCR)-based therapies, have opened new avenues for improving outcomes in CCA. This review provides a comprehensive overview of the current state of T cell therapies for CCA, focusing on CAR T cell therapy. It highlights key challenges, including the complex tumor microenvironment and immune evasion mechanisms, and the progress made in preclinical and clinical trials. The review also discusses ongoing clinical trials targeting specific CCA antigens, such as MUC1, EGFR, and CD133, and the evolving role of precision immunotherapy in enhancing treatment outcomes. Despite significant progress, further research is needed to optimize these therapies for solid tumors like CCA. By summarizing the most recent clinical results and future directions, this review underscores the promising potential of T cell therapies in revolutionizing CCA treatment.

Fixed point subgroups of a supertight automorphism

Let G be an infinite simple group of finite Morley rank and α a supertight automorphism of G so that the fixed point subgroup P n : = C G ( α n ) is pseudofinite for all n ∈ N ∖ { 0 } . It is know (using CFSG) that the socle S n : = Soc ( P n ) is a (twisted) Chevalley group over a pseudofinite field. We prove that there is r ∈ N ∖ { 0 } so that for each n we have [ P n : S n ] < r and that there is no m ∈ N ∖ { 0 } so that for each n the sizes of the Sylow 2-subgroups of S n are bounded by m. We also note that in the recent identification result of G under the assumption pr 2 ( G ) = 1 , the use of CFSG is not needed.

The Gonchar–Chudnovskies conjecture and a functional analogue of the Thue–Siegel–Roth theorem

This article examines the Gonchar–Chudnovskies conjecture about the limited size of blocks of diagonal Padé approximants of algebraic functions. The statement of this conjecture is a functional analogue of the famous Thue–Siegel–Roth theorem. For algebraic functions with branch points in general position, we will show the validity of this conjecture as a consequence of recent results on the uniform convergence of the continued fraction for an analytic function with branch points. We will also discuss related problems on estimating the number of “spurious” (“wandering”) poles for rational approximations (Stahl’s conjecture), and on the appearance and disappearance of defects (Froissart doublets).

CO2 Hydrogenation on Ru Single-Atom Catalyst Encapsulated in Silicalite: a DFT and Microkinetic Modeling Study.

The critical levels of CO2 emissions reached in the past decade have encouraged researchers into finding techniques to reduce the amount of anthropogenic CO2 expelled to the atmosphere. One possibility is to capture the produced CO2 from the source of emission or even from air (i.e., direct air capture) by porous materials (e.g., zeolites and MOFs). Among the different usages of captured CO2, its conversion into light fuels such as methane, methanol, and formic acid is essential for ensuring the long-awaited circular economy. In the last years, single-atom catalysts encapsulated in zeolites have been considered to this purpose since they exhibit a high selectivity and activity with the minimum expression of catalytic species. In this study, a detailed mechanism composed by 47 elementary reactions, 42 of them in both forward and reverse directions and 5 of them that correspond to the desorption of gas products just forwardly studied), has been proposed for catalytic CO2 hydrogenation over Ru SAC encapsulated in silicate (Ru1@S-1). Periodic density functional theory (DFT) calculations along with microkinetic modeling simulations at different temperatures and pressures were performed to evaluate the evolution of species over time. The analysis of the results shows that carbon monoxide is the main gas produced, followed by formic acid and formaldehyde. The rate analysis shows that CO(g) is formed mainly through direct dissociation of CO2 (i.e., redox mechanism), whereas COOH formation is assisted by OH. Moreover, the Campbell's degree of rate control analysis suggests that the determining steps for the formation of CO(g) and CH2O(g) gas species are their own desorption processes. The results obtained are in line with recent experimental and theoretical results showing that Ru1 SACs are highly selective to CO(g), whereas few atom clusters as Ru4 increase selectivity toward methane formation.

Recent results from the DANSS experiment

Recent results from the DANSS experiment

Probing gluon GTMDs of the proton in deep inelastic diffractive dijet production at HERA

We calculate several differential distributions for diffractive dijets production in ep→e′jet jetp in the perturbative QCD dipole approach using off diagonal unintegrated gluon distributions (generalized transverse momentum dependent distributions, GTMDs). Different models from the literature are used. We concentrate on the contribution from exclusive qq¯ dijets. Results of our calculations are compared to H1 and ZEUS data, including specific experimental cuts in our calculations. In general, except for one GTMD, our results are below the HERA data. The considered mechanism is expected to gives a sizeable contribution to the ZEUS data, while it is negligible in the kinematics of the H1 measurement. This is in contrast to recent results from the literature where the normalization was adjusted to some selected distributions of the H1 collaboration and no agreement with other observables was checked. The ZEUS data provide stricter limitations on the GTMDs than the H1 data. We conclude, based on comparison to different observables, that the calculated cross sections are only a small fraction of the measured ones which contain probably also processes with pomeron remnant. Alternatively one could try to explain the experimental data by inclusion of qq¯g component of the photon wave function. We present also azimuthal correlations between the sum and the difference of dijet transverse momenta. The cuts on transverse momenta of jets generate corresponding azimuthal correlations that can be misidentified as due to elliptic gluon distributions. Published by the American Physical Society 2024

Beyond T-Trials, T4DM and TRAVERSE: the next large testosterone randomized controlled trial.

Lower testosterone concentrations have been associated with poorer health outcomes in ageing men, but proving causality and demonstrating potential for therapeutic benefit requires randomized clinical trials (RCTs). This review discusses recent observational findings and results of major testosterone RCTs, to explore the need for another, larger trial. Evidence of Leydig cell impairment emerges in men above the age of 70 years. Lower testosterone is associated with diabetes risk, and also risk of incident dementia. An individual participant data meta-analysis found that below thresholds of testosterone of 7.4 nmol/L and 5.3 nmol/l respectively, risks of all-cause mortality and cardiovascular deaths in men increased. Testosterone for the Prevention of Type 2 Diabetes Mellitus (T4DM), a multicentre RCT, showed that testosterone treatment prevented or reverted type 2 diabetes in men at high risk. Testosterone Replacement Therapy for Assessment of Long-term Vascular Events and Efficacy Response in Hypogonadal Men (TRAVERSE), a cardiovascular safety trial, demonstrated cardiovascular and prostate safety of testosterone treatment in men with or at risk of cardiovascular disease. T4DM confirmed findings from the Testosterone Trials (T-Trials) that testosterone improved sexual function, and bone microarchitecture and density. However, in TRAVERSE, testosterone-treated men had a higher risk of clinical bone fractures, but not major osteoporotic fractures. Men with disorders of the hypothalamic-pituitary-testicular (HPT) axis causing androgen deficiency warrant consideration for testosterone therapy. In men with an intact HPT axis, testosterone treatment is a pharmacological intervention which requires justification from high quality RCT data. Currently, there is insufficient evidence to justify wider use of testosterone for prevention of cardiometabolic disease. However, there is scope for another large testosterone RCT to investigate whether testosterone treatment might, in older men, extend disability-free survival.

Pion gravitational form factors in the QCD instanton vacuum. II

We revisit the hard QCD contributions to the pion gravitational form factors, in terms of the twist-2,3 pion distribution amplitudes (DAs), including novel semihard contributions from the instantons. The pion DAs are evaluated in the QCD instanton vacuum and then properly evolved to higher resolution. The results are compared to our recent results from the QCD instanton vacuum, as well as Bethe-Salpeter calculations and recent lattice data. The interpolated hard and soft contributions to the pion D form factor are used to derive the (gravitational) pressure and shear within the pion, with a clear delineation of their range. Published by the American Physical Society 2024

Augmenting BERT to Model Remediation Processes in Finnish Countermedia

This paper showcases a supervised machine learning classifier to bridge the gap between qualitative and quantitative research in media studies, leveraging recent advancements in data-driven approaches. Current machine learning methods make it possible to gain insights from large datasets that would be impractical to analyze with more traditional methods. Supervised document classification presents a good platform for combining specific domain knowledge and close reading with broader quantitative analysis. The study focuses on a dataset of 37 185 articles from the Finnish countermedia publication MVlehti, from which a randomly sampled 997 articles were annotated into three categories based on frame analysis. Contextual sequence representations from the finBERT language model, topic distributions from a trained topic model, and a structural, HTML-aware featureset developed in prior work are employed as classification features. The hypothesis that BERT-based embeddings could be improved upon by augmenting them with additional information is supported by recent promising results in natural language benchmarks and tasks (Peinelt, Nguyen, and Liakata 2020; Glazkova 2021). In our study, combining contextual embeddings with topics resulted in only marginal performance increases, and this improvement was observed mostly in minority classes. Despite this, potential future developments to achieve better classification performance are outlined. Based on the experiments, automated frame analysis with neural classifiers is possible, but the accuracy is not yet sufficient for inferences of high certainty.

Recent results and outstanding questions on the response of the electrodynamics of the low latitude ionosphere to solar wind and magnetospheric disturbances

Storm-time ionospheric electrodynamics effects have been the subject of extensive studies. The solar wind/magnetosphere/ionosphere and thermosphere disturbance wind dynamos have long been identified as the main drivers of low latitude storm-time electrodynamics. Extensive detailed studies showed that climatology of low latitude disturbance electric fields and currents is in good agreement with results from global theoretical and numerical models. Over the last decade, however, numerous studies have highlighted that the response of low latitude electrodynamics to enhanced geomagnetic activity is significantly more complex than previously considered. It is now clear that the electrodynamic disturbance processes are affected by a larger number of solar wind and magnetospheric parameters and that they also have more significant spatial dependence. This is especially pronounced during and after large geomagnetic storms when multiple simultaneous disturbance processes are also active. In this work, we briefly review the main past experimental and modeling studies of low latitude disturbance electric fields, highlight new results, discuss outstanding questions, and present suggestions for future studies.

Phonons in stringlet-land and the boson peak

Solid materials that deviate from the harmonic crystal paradigm exhibit characteristic anomalies in the specific heat and vibrational density of states (VDOS) with respect to Debye's theory predictions. The boson peak (BP), a low-frequency excess in the VDOS over Debye lawg(ω)∝ω2, is certainly the most famous among them; nevertheless, its origin is still subject of fierce debate. Recent simulation works provided strong evidence that localized one-dimensional string-like excitations (stringlets) might be the microscopic origin of the BP. In this work, we study the dynamics of acoustic phonons interacting with a bath of vibrating 1D stringlets with exponentially distributed size, as observed in simulations. We show that stringlets strongly renormalize the phonon propagator and naturally induce a BP anomaly in the VDOS, corresponding to the emergence of a dispersionless BP flat mode. Additionally, phonon-stringlet interactions produce a strong enhancement of sound attenuation and a dip in the speed of sound near the BP frequency, consistent with experimental and simulation data. The qualitative trends of the BP frequency and intensity are predicted within the model and shown to be in good agreement with previous observations. In summary, our results substantiate with a simple theoretical model the recent simulation results by Hu and Tanaka claiming the origin of the BP from stringlet dynamics.

Evaluating the Viability and Optimization of Plasma Pilot Plants

Nuclear fusion stands as a promising avenue for achieving a sustainable and abundant energy source. Central to this endeavor is the development of effective pilot plants capable of demonstrating the feasibility of fusion power on a commercial scale. This paper provides a comprehensive evaluation of three leading magnetic confinement fusion configurations: the Advanced Tokamak (AT), Spherical Tokamak (ST), and Compact Stellarator (CS).The Tokamak, characterized by its toroidal shape and strong magnetic fields, has been the most researched and developed fusion device. The analysis focuses on the challenges related to maintaining stability and minimizing disruptions. Furthermore, the optimization strategies involving advanced materials, superconducting magnets, and innovative plasma control techniques are discussed to enhance the Tokamak's viability. In contrast, the Spherical Tokamak, a variant with a more compact and spherical design, promises improved current advancements including the handling of higher heat loads and magnetic field configurations. The Stellarator, with its complex, twisted magnetic field structure, eliminates the need for continuous external current drive, addressing some intrinsic issues of the Tokamak. By comparing these configurations, the paper identifies the relative strengths and weaknesses of each approach in terms of confinement efficiency, operational stability, and engineering feasibility. The evaluation is supported by recent experimental data, simulation results, and technological advancements. Finally, the paper proposes a roadmap for the future development of fusion pilot plants, highlighting the need for an integrated approach that leverages the strengths of each configuration while addressing their individual challenges. The synthesis of this evaluation underscores the importance of continued research, cross-collaboration, and investment in advanced technologies to realize the goal of practical and economically viable fusion energy. This comparative analysis aims to provide a strategic framework for policymakers, researchers, and engineers in the fusion community, fostering informed decisions and prioritizing research efforts towards the most promising fusion energy configurations.

Classroom to Clinic: Universities Need to Support The Next Generation of Clinical Academics

The General Medical Council’s current version of Outcomes for Doctors sets out three key areas of expertise for tomorrow’s doctors: professional values &amp; behaviours, professional skills, and professional knowledge. (1) Each of these competencies further develops into numerous core skills every student should attain at medical school. While the learning outcomes set under Clinical Research &amp; Scholarship (part of Outcome 3: Professional Knowledge) could usually be attained through numerous instances across a typical medical school curriculum, opportunities to put research skills into practice have remained relatively competitive and scarce. This represents an emerging challenge across the career spectrum, particularly in the UK as the Medical Schools Council warns that the NHS Long Term Workforce Plan 2031-32 could be jeopardised if the number of clinical academics is not maintained.(2) Facilitated by the impacts of an aging workforce alongside years of underinvestment – NHS trusts and medical schools need to work quickly to address barriers in training and retaining the next generation of clinical academics.(3) Clinical Academics are the foundation of the future of medical schools. However, much more must be done to introduce, facilitate, and encourage medical students to consider the option of training as a clinical academic. Investing in opportunities for medical students to get involved in research and teaching early on in their medical career, could be a solution not just to tackle this future workforce challenge but also to offer better career prospects. This is supported by evidence from research on matched-cohort studies conducted in Australia &amp; New Zealand demonstrating an encouraging statistic independent of academic confounding variables. (4,5) Medical students who published research in medical student journals were significantly more likely to be associated with higher degree attainment, PubMed® indexed publications and in some cases, more likely to enter surgical training or their chosen specialty. However, getting involved in clinical research as a medical student remains challenging. Lack of opportunities, competitive funding calls, and fewer supervisors willing to take on the burden of training students are only some of the many barriers students currently face in getting involved. Recent results from a survey by the University of Glasgow’s Medical School demonstrated reassuring enthusiasm for a career in clinical research/teaching among a small sample size of 55 students. Commenting on these findings, Professor Iain McInnes, Head of the College of Medical, Veterinary and Life Sciences, said ‘.... supporting clinical academics at all stages of their career is a top priority for our college and this survey shows that the pipeline for the future of academia is in good health indeed!’. On the balance, the need of the hour must now focus on retaining this enthusiasm by investing in opportunities and offering pathways to ensure medical students can actively engage in academia. Several steps including enhancing funding, fostering stronger mentorship and networking opportunities, promoting interdisciplinary collaboration, and recognizing research efforts by medical students can go a long way in pursuing students to consider a rewarding career in clinical academia.

Applications of the Hahn-Banach Theorem, a Solution of the Moment Problem and the Related Approximation

We start by an application the of Krein–Milman theorem to the integral representation of completely monotonic functions. Elements of convex optimization are also mentioned. The paper continues with applications of Hahn–Banach-type theorems and polynomial approximation to obtain recent results on the moment problem on the unbounded closed interval [0,+∞). Necessary and sufficient conditions for the existence and uniqueness of the solution are pointed out. Operator-valued moment problems and a scalar-valued moment problem are solved.

Recent Advances in Wearable Textile-Based Triboelectric Nanogenerators.

We review recent results on textile triboelectric nanogenerators (T-TENGs), which function both as harvesters of mechanical energy and self-powered motion sensors. T-TENGs can be flexible, breathable, and lightweight. With a combination of traditional and novel manufacturing methods, including nanofibers, T-TENGs can deliver promising power output. We review the evolution of T-TENG device structures based on various textile material configurations and fabrication methods, along with demonstrations of self-powered systems. We also provide a detailed analysis of different textile materials and approaches used to enhance output. Additionally, we discuss integration capabilities with supercapacitors and potential applications across various fields such as health monitoring, human activity monitoring, human-machine interaction applications, etc. This review concludes by addressing the challenges and key research questions that remain for developing viable T-TENG technology.

Toughening Mechanism in Nanotwinned Boron Carbide: A Molecular Dynamics Study.

Boron carbide ceramics are potentially ideal candidates for lightweight bulletproof armor, but their use is currently limited by their low fracture toughness. Recent experimental results have shown that sintered samples with high twin densities exhibit high fracture toughness, but the toughening mechanism and associated crack propagation process of nanotwinned boron carbide at the atomic scale remain a mystery. Reported here are molecular dynamics simulations with a reactive force field potential to investigate how nanoscale twins affect the fracture toughness of boron carbide ceramics. The results show that the strength disparity on either side of a twin boundary is the fundamental reason for the toughening effect; the twin boundary impedes crack propagation only when the crack moves to a region of higher fracture strength. The fracture toughness of nanotwinned boron carbide is greatly affected by the angle between the twin boundary and the prefabricated crack. At an angle of 120°, the twin boundary provides the maximum toughening effect, enhancing the toughness by 32.72%. Moreover, phase boundaries-another common structure in boron carbide ceramics-have no toughening effect. This study provides new insights into the design of boron carbide ceramics with high fracture toughness.

Fractionary charged particles confronting lepton flavor violation and the muon’s anomalous magnetic moment

In light of the recent result published by the Fermilab Muon [Formula: see text] experiment, we investigate a simple model that includes particles of fractional electric charges: a color-singlet fermion and a scalar with charges [Formula: see text] and [Formula: see text], respectively. The impact of these particles on the muon anomalous magnetic moment is examined, particularly the restrictions on their Yukawa couplings with the light leptons. Given that lepton flavor violation processes impose stringent constraints on certain scenarios beyond the Standard Model, we evaluate the one-loop contribution of the new particles to [Formula: see text] in order to identify regions in the parameter space consistent with the Fermilab results and compatible with the current and projected limits on the branching ratio [Formula: see text]. Taking into account the current lower bound for the masses of fractionary charged particles, which is around 634[Formula: see text]GeV, we show that the mass of the scalar particle with fractional charge must exceed 1[Formula: see text]TeV. In particular, we present some estimatives for double production of the color-singlet fermion at the 14[Formula: see text]TeV LHC. Finally, we also study the validity of our model in light of the QCD lattice results on the muon [Formula: see text].

Elephant Random Walk with a Random Step Size and Gradually Increasing Memory and Delays

The ERW model was introduced twenty years ago to study memory effects in a one-dimensional discrete-time random walk with a complete memory of its past throughout a parameter p between zero and one. Several variations of the ERW model have recently been introduced. In this work, we investigate the asymptotic normality of the ERW model with a random step size and gradually increasing memory and delays. In particular, we extend some recent results in this subject.