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A bstract Theories formulated in the arena of teleparallel geometries are generically plagued by ghost-like instabilities or other pathologies that are ultimately caused by the breaking of some symmetries. In this work, we construct a class of ghost-free theories based on a symmetry under Transverse Diffeomorphisms that is naturally realised in symmetric teleparallelism. We explicitly show their equivalence to a family of theories with an extra scalar field plus a global degree of freedom and how Horndeski theories and healthy couplings to matter fields can be readily accommodated.

In an age where artificial intelligence is reshaping the landscape of education and problem solving, our study unveils the secrets behind three digital wizards, ChatGPT-3.5, ChatGPT-4, and Google Bard, as they engage in a thrilling showdown of mathematical and logical prowess. We assess the ability of the chatbots to understand the given problem, employ appropriate algorithms or methods to solve it, and generate coherent responses with correct answers. We conducted our study using a set of 30 questions. These questions were carefully crafted to be clear, unambiguous, and fully described using plain text only. Each question has a unique and well-defined correct answer. The questions were divided into two sets of 15: Set A consists of “Original” problems that cannot be found online, while Set B includes “Published” problems that are readily available online, often with their solutions. Each question was presented to each chatbot three times in May 2023. We recorded and analyzed their responses, highlighting their strengths and weaknesses. Our findings indicate that chatbots can provide accurate solutions for straightforward arithmetic, algebraic expressions, and basic logic puzzles, although they may not be consistently accurate in every attempt. However, for more complex mathematical problems or advanced logic tasks, the chatbots’ answers, although they appear convincing, may not be reliable. Furthermore, consistency is a concern as chatbots often provide conflicting answers when presented with the same question multiple times. To evaluate and compare the performance of the three chatbots, we conducted a quantitative analysis by scoring their final answers based on correctness. Our results show that ChatGPT-4 performs better than ChatGPT-3.5 in both sets of questions. Bard ranks third in the original questions of Set A, trailing behind the other two chatbots. However, Bard achieves the best performance, taking first place in the published questions of Set B. This is likely due to Bard’s direct access to the internet, unlike the ChatGPT chatbots, which, due to their designs, do not have external communication capabilities.

In this paper we explore generalizations of metric structures of the gravitational wave type to geometries containing an independent connection. The aim is simply to establish a new category of connections compatible, according to some criteria, to the known metric structures for gravitational waves and, additionally, provide some properties that can be useful for the search of solutions of this kind in different theories.

Water governance has emerged as an important topic in the international arena and is acknowledged to be a crucial factor for adequate and sustained progress towards achieving Sustainable Development Goal (SDG) 6. However, there is not enough clarity about the practical meaning of the term “water governance” and how to work with it. This paper reviews the term’s use, to reveal how the concept is understood, referred to, and implemented in practice by different stakeholders. Based on literature review and consultations with experts, we identify and describe the core components of water governance (functions), describe their potential qualities when performed (attributes), and how they interrelate with the values and aspirations of the different stakeholders to achieve certain outcomes. These different components are described in detail to construct an operational framework to assess and work with water governance, which covers water and sanitation services delivery, water resources management and transboundary waters. This paper’s findings provide practical guidance for decision makers and practitioners on how action-oriented water governance processes can be meaningfully designed, and ultimately, how to strengthen efforts aiming to improve water governance.

Magnesium aluminate spinel nanoparticles (MgAl2O4-S-NPs) represent a promising class of nanoceramics with potential biomedical applications due to their physicochemical stability and antimicrobial properties. This study aimed to determine the structural characteristics, composition, and biological performance of MgAl2O4 spinel nanoparticles that were synthesized via a mechanochemical method. Structural and compositional characterization was performed using X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HR-TEM). Antibacterial activity was evaluated against Helicobacter pylori and Enterococcus faecalis using bacterial viability assays. Structural and morphological analyses confirmed the successful formation of single-phase cubic MgAl2O4 with a polyhedral morphology and nanoscale size distribution. Bacterial viability was quantified through optical density measurements following exposure to MgAl2O4-S-NPs at different concentrations. The nanoparticles exhibited both bacteriostatic and bactericidal effects, with activity being demonstrated against the tested bacterial strains. Mechanochemically synthesized MgAl2O4-S-NPs are promising candidates for biomedical applications, including dental materials, antimicrobial coatings, and infection-control strategies. Overall, the findings highlight the potential of MgAl2O4-S-NPs as effective antimicrobial agents that can be produced through an environmentally friendly synthesis route.

Afghanistan experiences frequent damaging earthquakes, and the widespread use of unreinforced adobe and Pakhsa construction leads to high casualty rates and severe housing losses. Traditional earthen buildings exhibit low tensile capacity, rapid stiffness degradation, and brittle failure, often collapsing at drift levels below 0.5–0.6% or at modest ground motions. Reinforcement techniques evaluated in international experimental studies—such as timber confinement, flexible steel wire mesh, geogrids, and high-quality plastic fencing—have demonstrated measurable improvements, including 30–200% increases in lateral strength, three- to seven-fold increases in ductility, and out-of-plane capacity enhancements of more than two-fold when properly anchored. This study synthesises research findings and global earthen building codes and guidelines to develop a practical, context-appropriate benchmark house model for Afghanistan. The proposed model integrates representative wall geometries, concentrated flat-roof loading, and realistic construction capabilities observed across the country. Three reinforcement alternatives are presented, each designed to be low-cost, compatible with locally available materials, and constructible without specialised equipment. By linking quantitative performance evidence with context-specific construction constraints, the study provides a technically grounded and implementable pathway for improving the seismic safety of rural earthen dwellings in Afghanistan. The proposed benchmark model offers a robust foundation for future national guidelines and for the design and retrofitting of safer, more resilient housing.

We undertake the construction of quadratic parity-violating terms involving the curvature in the four-dimensional metric-affine gravity. We demonstrate that there are only 12 linearly independent scalars, plus an additional one that can be removed by using the Pontryagin invariant. Several convenient bases for this sector are provided in both components and differential form notation. We also particularize our general findings to some constrained geometries like Weyl–Cartan and metric-compatible connections.

The impact of systemic inflammation in nigral dopaminergic cell loss remains unclear. Here, we have investigated the role of peripheral inflammation induced by systemic lipopolysaccharide (LPS) administration in the MPTP-based model of Parkinson’s disease. Brain inflammation, microglia and astroglia activation, disruption of the blood–brain barrier (BBB) and integrity of the nigrostriatal dopaminergic system were evaluated in response to i.p. injection of LPS, MPTP or the combination of both. Our results showed that combinative treatment exacerbates microglia activation and enhances (i) the appearance of galectin-3-positive microglia, recently identified as microglial disease-associated phenotypic marker, (ii) the up-regulation of pro-inflammatory cytokines, (iii) the occurrence of A1 neurotoxic astrocytes, (iv) the breakdown of the BBB, and (v) the loss of dopaminergic neurons in the substantia nigra. Microglia activation was triggered earlier than other degenerative events, suggesting that over-activation of microglia (including different polarization states) may induce dopaminergic neuron loss by itself, initiating the endless cycle of inflammation/degeneration. Our study revitalizes the importance of peripheral inflammation as a potential risk factor for Parkinson’s disease and raises the possibility of using new anti-inflammatory therapies to improve the course of neurodegenerative diseases, including those directly aimed at modulating the deleterious activity of disease-associated microglia.

Trackways and tracemakers preserved together in the fossil record are rare. However, the co-occurrence of a drag mark, together with the dead animal that produced it, is exceptional. Here, we describe an 8.5 m long ammonite drag mark complete with the preserved ammonite shell (Subplanites rueppellianus) at its end. Previously recorded examples preserve ammonites with drag marks of < 1 m. The specimen was recovered from a quarry near Solnhofen, southern Germany. The drag mark consists of continuous parallel ridges and furrows produced by the ribs of the ammonite shell as it drifted just above the sediment surface, and does not reflect behaviour of the living animal.

In this work, we revise the concept of foliation and related aspects that are crucial when formulating the Hamiltonian evolution for various theories beyond General Relativity. In particular, we show the relation between the kinematic characteristics of timelike congruences (observers) and the existence of foliations orthogonal to them. We then explore how local Lorentz transformations acting on observers affect the existence of transversal foliations, provide examples, and discuss the implications of these results for the 3+1 formulation of tetrad modified theories of gravity.