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The pure rotational and rovibrational spectra of the ν27 –NH2 torsion of cyclopropylamine (CPA) in the far-infrared region were measured with a high-resolution Fourier transform infrared coupled to a synchrotron. The complex spectra reflect the presence of both trans and gauche conformers. Analysis of the pure rotational spectra (34–64 cm−1) yielded accurate rotational and centrifugal distortion constants of the ground and first two torsional excited states of trans-CPA. The fundamental, hot bands and weak overtones were identified and assigned in the 200–550 cm−1 range. Global analysis of over 19 000 transitions provides accurate energy levels of the torsional polyads up to vT = 3. The torsional levels and their rotational constants were in agreement with the theoretical results from quasiadiabatic channel reaction path Hamiltonian (RPH) calculations, emphasizing the need for molecular-specific theoretical treatments for large amplitude motions. Tunneling components of the torsional fundamental of gauche-CPA were assigned based on the RPH results and symmetry considerations, differing from previous experimental and theoretical work. This comprehensive spectroscopic characterization of CPA is crucial for its potential detection in the interstellar medium as a precursor to complex prebiotic molecules, providing essential data for future astronomical searches and advancing our understanding of nitrogen-containing organic molecules in space. [ABSTRACT FROM AUTHOR]

The lack of observational data for the AlO molecule in the mesosphere/lower thermosphere may be due to ablated aluminum reacting quickly to form other species. Previously proposed reaction pathways show that aluminum could be ablated in the atmosphere from meteoritic activity, but there currently exist very limited spectroscopic data on the intermediates in these reactions, limiting the possible detection of said molecules. As such, rovibrational spectroscopic data are computed herein using quartic force field methodology at four different levels of theory for the neutral intermediates AlCO3, OAlO2, and HOAlO2. Each molecule exhibits multiple vibrational modes with large vibrational transition intensities. For instance, the C–O stretch (ν1) in AlCO3 has a harmonic intensity of 536 km mol−1, the Al–O stretch (ν2) in OAlO2 has an intensity of 678 km mol−1, and the out-of-plane torsion (ν9) in HOAlO2 has an intensity of 158 km mol−1. All three molecules have exceptionally large dipole moments of 6.27, 4.21, and 5.04 D, respectively. These properties indicate that all three molecules are good candidates for potential atmospheric observation utilizing vibrational and/or rotational spectroscopic techniques. [ABSTRACT FROM AUTHOR]

A general formulation of the strong coupling between photons confined in a cavity and molecular electronic states is developed for the state-interaction state-average spin-restricted ensemble-referenced Kohn–Sham method. The light–matter interaction is included in the Jaynes–Cummings model, which requires the derivation and implementation of the analytical derivatives of the transition dipole moments between the molecular electronic states. The developed formalism is tested in the simulations of the nonadiabatic dynamics in the polaritonic states resulting from the strong coupling between the cavity photon mode and the ground and excited states of the penta-2,4-dieniminium cation, also known as PSB3. Comparison with the field-free simulations of the excited-state decay dynamics in PSB3 reveals that the light–matter coupling can considerably alter the decay dynamics by increasing the excited state lifetime and hindering photochemically induced torsion about the C=C double bonds of PSB3. The necessity of obtaining analytical transition dipole gradients for the accurate propagation of the dynamics is underlined. [ABSTRACT FROM AUTHOR]

Introduction: Recognizing testicular torsion is extremely important in patients presenting to the emergency department (ED) with acute scrotal pain. Traditional manual detorsion techniques are frequently employed by emergency physicians but are not always successful. Delays in detorsion increase the risk of testicular infarction and infertility, and the need for orchiectomy. Novel techniques such as the testicular traction technique have been described as a potential solution for difficult-to-detorse testicles.Case Report: Our case report describes a 20-year-old male with no significant past medical history who presented to a rural ED with acute, atraumatic testicular pain secondary to testicular torsion with an intact cremasteric reflex. After confirming the diagnosis using Doppler ultrasound, manual detorsion using the traditional “open book” technique was attempted and unsuccessful. The patient was subsequently successfully detorsed using the novel testicular traction technique.Conclusion: The testicular traction technique is a safe, rapid, and effective primary or adjunctive technique in manual testicular detorsion. Given the time-sensitive nature of testicular torsions, adjunctive techniques play a crucial role in managing challenging detorsions, particularly in resource-limited rural settings with limited access to urologic services. Although it is commonly thought that the cremasteric reflex is absent in testicular torsions, it may be present in rare circumstances, and its presence should not be an absolute in ruling out torsion.

We present a novel approach for systematically exploring the conformational space of small molecules with multiple internal torsions. Identifying unique conformers through a systematic conformational search is important for obtaining accurate thermodynamic functions (e.g., free energy), encompassing contributions from the ensemble of all local minima. Traditional geometry optimizers focus on one structure at a time, lacking transferability from the local potential-energy surface (PES) around a specific minimum to optimize other conformers. In this work, we introduce a physics-driven meta-Gaussian processes (meta-GPs) method that not only enables efficient exploration of target PES for locating local minima but, critically, incorporates physical surrogates that can be applied universally across the optimization of all conformers of the same molecule. Meta-GPs construct surrogate PESs based on the optimization history of prior conformers, dynamically selecting the most suitable prior mean function (representing prior knowledge in Bayesian learning) as a function of the optimization progress. We systematically benchmarked the performance of multiple GP variants for brute-force conformational search of amino acids. Our findings highlight the superior performance of meta-GPs in terms of efficiency, comprehensiveness of conformer discovery, and the distribution of conformers compared to conventional non-surrogate optimizers and other non-meta-GPs. Furthermore, we demonstrate that by concurrently optimizing, training GPs on the fly, and learning PESs, meta-GPs exhibit the capacity to generate high-quality PESs in the torsional space without extensive training data. This represents a promising avenue for physics-based transfer learning via meta-GPs with adaptive priors in exploring torsional conformer space. [ABSTRACT FROM AUTHOR]

Electron transport through a variety of helical structures has been shown to exhibit high-efficiency spin filtering, which is called chirality-induced spin selectivity (CISS). In this paper, we consider a helical chain of atomic p orbitals, which has been employed as a model in exploring the mechanism of CISS in previous theories, and show that the interatomic hopping along the helical chain induces an effective magnetic field (EMF) acting on the atomic orbital angular momentum (OAM). In chains where the curvature and torsion of the helix are small, we find that the EMF on the binormal component of the atomic OAM is created by the curvature, while that on the tangential component is produced by the torsion. We show that such coupling of the atomic OAM and the interatomic hopping leads to current-induced orbital and spin polarizations. We expect that the present coupling, which is expressed locally, can be used to estimate orbital and spin polarizations locally induced in molecules and solids. [ABSTRACT FROM AUTHOR]

Translation abstract Application areas of calculation models for the torsional load‐bearing capacity of segment joints – Wind turbines with annular cross‐sectionWind turbines play a decisive role in the reorientation of our energy supply. The torsional load‐bearing behaviour of the towers must be analysed in detail and suitable calculation models developed and established to ensure the safe and resource‐saving construction of these plants. In recent years, two important models have been developed to determine the torsional resistance of the horizontal segment joints of wind towers. However, it has not yet been possible to specify their areas of application. Using new test data and analyses, it has now been possible to determine the mechanical validity limits of the models. With the parameter space presented in this paper, the areas of application of the most important calculation models for the torsional load‐bearing capacity of dry joints with annular cross‐sections can be defined and thus an assignment can also be made for wind turbine towers commonly used in practice. [ABSTRACT FROM AUTHOR]

We establish the mathematical fundamentals for a unified description of curvature, torsion, and non-metricity 2-forms in the way extending the so-called Möbius representation of the affine group, which is the method to convert the semi-direct product into the ordinary matrix product, to revive the fertility of gauge theories of gravity. First of all, we illustrate the basic concepts for constructing the metric-affine geometry. Then the curvature and torsion 2-forms are described in a unified manner by using the Cartan connection of the Möbius representation of the affine group. In this unified-description, the curvature and torsion are derived by Cartan’s structure equation with respect to a common connection 1-form. After that, extending the Möbius representation, the dilation and shear 2-forms, or equivalently, the non-metricity 2-form, are introduced in the same unified manner. Based on the unified-description established in this paper, introducing a new group parametrization and applying the Inönü–Wigner group contraction to the full theory, the relationships among symmetries, geometric quantities, and geometries are investigated with respect to the three gauge groups: the metric-affine group and its extension, and an extension of the (anti)-de Sitter group in which the non-metricity exists. Finally, possible applications to theories of gravity are briefly discussed. [ABSTRACT FROM AUTHOR]

Hybrid manufacturing processes integrate multiple manufacturing techniques to leverage their respective advantages and mitigate their limitations. This study combines additive manufacturing and injection molding, aiming to efficiently produce components with extensive design flexibility and functional integration. The research explores the interfacial fusion bonding of hybrid additively manufactured components under torsional loading. Specifically, it examines the impact of various surface treatments on injection molded parts and the influence of different build chamber temperatures during additive manufacturing on torsional strength. Polycarbonate components, neat, with glass or carbon fiber-reinforcement, are produced and assessed for dimensional accuracy, torsional strength, and fracture behavior. The findings emphasize the critical role of surface treatment for the injection molded components before additive manufacturing. Additionally, the study identifies the influence of chamber temperatures on both dimensional accuracy and torsional strength. Among all investigated materials, plasma-treated neat samples exhibited the best torsional strength. The torsional strength was increased by up to 87 % by actively heating the build chamber to 186 °C for neat polycarbonate. These insights aim to advance the quality and performance of hybrid additively manufactured components, broadening their application potential across diverse fields. [ABSTRACT FROM AUTHOR]

The drift demand of plan-asymmetric buildings in low seismicity regions was studied by employing Incremental Dynamic Analysis to track the influence of torsion. A stepped increase in the (3D/2D) drift demand ratio was observed as the limit of yield was surpassed. This amplification phenomenon, which is typically muted with high, or moderate, ductility demand has not been reported in research literature on building responses in high seismic conditions. However, the undesirable torsion-induced amplification cannot be ignored as limited ductile buildings are particularly vulnerable depending on the disposition, number, size and orientation of the structural walls. [ABSTRACT FROM AUTHOR]

Chiral torsional anomalies have recently been applied in condensed matter and models of gravitation and quantum field theory, in particular in Dirac and Weyl materials. Moreover, Einstein–Cartan space–time elastic gauge spaces with vanishing spin connection have appeared in the teleparallelism framework. Recently, Ciappina et al. (PRD (2020)) have investigated torsion in quantum field theory through time loops on Dirac materials endowed with torsion in (2 + 1)-dimensional space–time where the third dimension is replaced by time dimension. They considered Riemann-flat spaces graphenes for example. In this paper, a space–time teleparallel geometry is used where we encoded physical information of Burgers vectors on Dirac curved materials (GdA, CQG 38 (2021)). It is shown that when the magnetic or pseudo-magnetic field is encoded in this metric one obtains an interesting (2 + 1)-dimensional space–time is shown to lead to pseudo-Maxwell equations. We also show that a Riemann-flat grapheno, for example, imposes a vanishing Nieh–Yan (NY) torsional anomaly, whereas a curved Dirac material presents a non-vanishing NY anomaly. Torsion-induced holonomy on Dirac materials is investigated. Signatures of chiral dynamo effects in Dirac materials from the chiral chemical potential encoded into the covariant derivative are found. It is shown that in the absence of chiral effect the magnetic field torsion contribution decays, whereas in the chiral dynamo case, a dynamo effect is found. It is shown that from the interaction of chiral chemical potential with torsion an effective chiral chemical potential is found, which depends on the zero-component of Cartan torsion. [ABSTRACT FROM AUTHOR]

Infection of the scrotum and its contents is the most common cause of acute scrotum. Imaging plays an important role in evaluating disease extent, severity and its complications. Sonography is the modality of choice for imaging the acute scrotum. This pictorial review discusses the varied clinical and imaging features of scrotal infections and their complications, with correlative CT, when available. [ABSTRACT FROM AUTHOR]

Purpose: In the milieu of emergency medicine, pelvic and lower abdominal pain present recurrently, with ovarian torsion posing a formidable diagnostic quandary amid multifarious etiologies. Given the burgeoning reliance on CT in acute care settings, it invariably assumes primacy as the principal imaging modality. This study endeavors to elucidate the CT imaging manifestations encountered by surgically confirmed ovarian torsion patients and utilizing CT to differentiate necrosis. Methods: A retrospective analysis (January, 2015- April, 2019) utilizing hospital archives was conducted on patients diagnosed with ovarian torsion, post-surgery. Inclusion criteria encompassed patients who underwent CT examinations within one week of diagnosis. A large array of CT findings encompassing midline orientation, uterine deviation, intraovarian hematoma/mass, and multiple others were systematically documented. Results: 90 patients were diagnosed with ovarian torsion- 53 (59%) had CT within one week of diagnosis, 41(77%) underwent a CT with IV contrast and 12 (23%) without IV contrast. Mean age was 43 years (range 19–77 years), with near equal distribution of involvement of each ovary. Mean maximum ovarian diameter was 11.7 ± 6.3 cm (4.2–34.8 cm). Most common imaging features include the presence of thickened pedicle (43/53, 81%), midline ovary (41/53, 77%), presence of thickened fallopian tube (31/49, 63%), and ipsilateral uterine deviation (33/53, 62%). Based on contemporaneous imaging report, torsion was diagnosed in 25/ 53 studies giving a sensitivity of 47%. Conclusion: Enlarged ovarian dimensions (> 3.0 cm), thickened vascular pedicle or fallopian tube, midline ovarian disposition with ipsilateral uterine deviation, and the presence of a whirlpool sign emerged as predominant CT imaging features in surgically confirmed ovarian torsion cases, serving as pivotal diagnostic aides for radiologists. Concomitant pelvic free fluid and intraovarian hematoma signify necrotic changes, indicative of ischemic severity and disease progression. [ABSTRACT FROM AUTHOR]

The ambiguity of the Weitzenböck connection is investigated from the perspective of frames. In doing so, the pure-tetrad formalism and the formalism with an affine connection are compared with each other; it is shown that the ambiguity in the affine connection is equivalent to that of the frame. The role played by the regularization procedure is discussed, and it is argued that the frame approach gives better results than any regularization procedure, including those that make use of a suitable choice of the affine connection. It is also argued that, for consistency, the Weitzenböck torsion must be either manifesting only gravitational effects or gravitational effects plus accelerations. Two possible interpretations for the torsion tensor are present, and an application to a frame that accelerates along the same direction as that of a p p -wave is used to show the consistence of these interpretations. Finally, some possible solutions to the well-known problems of the f (T) theories are proposed. [ABSTRACT FROM AUTHOR]

We obtain a homological characterisation of virtually free-by-cyclic groups among groups that are hyperbolic and virtually compact special. As a consequence, we show that many groups known to be coherent actually possess the stronger property of being virtually free-by-cyclic. In particular, we show that all one-relator groups with torsion are virtually free-by-cyclic, solving a conjecture of Baumslag. [ABSTRACT FROM AUTHOR]

In this paper, we give a complete classification of torsion pairs in m-cluster categories of type D when m is odd, denoted by C D n m , via a bijection to combinatorial objects called Ptolemy diagrams of type D. As applications, we classify m-rigid subcategories of C D n m , which gives Jacquet-Malo's classification of m-cluster tilting subcategories of C D n m . When m = 1, we generalizes the work of Holm, Jørgensen and Rubey [14] for the classification of torsion pairs in cluster categories of type Dn. Communicated by Steffen Oppermann [ABSTRACT FROM AUTHOR]

The sandpile group of a connected graph G, defined to be the torsion part of the cokernel of the graph Laplacian, is a subtle graph invariant with combinatorial, algebraic, and geometric descriptions. Extending and improving previous works on the sandpile group of hypercubes, we study the sandpile groups of the Cayley graphs of F 2 r , focusing on their poorly understood Sylow-2 component. We find the number of Sylow-2 cyclic factors for "generic" Cayley graphs and deduce a bound for the non-generic ones. Moreover, we provide a sharp upper bound for their largest Sylow-2 cyclic factors. In the case of hypercubes, we give exact formulae for the largest n–1 Sylow-2 cyclic factors. Some key ingredients of our work include the natural ring structure on these sandpile groups from representation theory, and calculation of the 2-adic valuations of binomial sums via the combinatorics of carries. [ABSTRACT FROM AUTHOR]

In this paper, we consider the Finsler p$p$‐Laplacian torsion equation. The domain of the problem is bounded by a conical surface supporting a Neumann‐type condition, and an unknown surface supporting both a Dirichlet and a Neumann condition. The case when the cone coincides with the punctured space is included. We show that the existence of a weak solution implies that the unknown surface lies on the boundary of a Finsler‐ball. Incidentally, some properties of the Finsler–Minkowski norms are proved here under mild smoothness assumptions. [ABSTRACT FROM AUTHOR]

The article presents investigations of microstructure and low‐temperature mechanical properties of nanostructured alloys CoCrFeMnNiVx (x = 0.15–0.75), processed by high‐pressure torsion (HPT) at temperatures of 300 and 77 K. While at x ≥ 0.5 the values of microhardness (Hv) and compression yield stress (σ0.2) in samples after HPT at 77 K are larger than those in samples after HPT at 300 K, for x ≤ 0.2 surprisingly the opposite effect is observed. As in case of the undeformed CoCrFeMnNiVx alloys, the behavior for vanadium concentrations x ≥ 0.5 can be related to the formation of tetragonal σ‐phase in addition to face‐centered cubic matrix, while the anomalous behavior for x ≤ 0.2 arises from the formation of HPT‐induced hexagonal martensitic phase. In the low‐temperature ranges, i.e., 20–300 K in case of HPT nanostructured CoCrFeMnNiV0.2, and 150–300 K in case of HPT nanostructured CoCrFeMnNiV0.5, dependences of σ0.2(T) show characteristics of thermally activated dislocation movement. For the first time in high‐entropy alloys, anomalous dependences of σ0.2(T) at temperatures 4.2–20 K for CoCrFeMnNiV0.2, and at 80–150 K for CoCrFeMnNiV0.5 are found, which indicate at the occurrence of nonthermal inertial dislocation movement. [ABSTRACT FROM AUTHOR]

The low toughness and structural stability of nanostructured materials are strongly related to the numerous grain boundaries and interfaces. Among other design stratgies, the use of low‐energy boundaries has turned out to provide the most comprehensive improvement of the property spectrum targeting on ductility, toughness, as well as thermal and microstructural stability upon mechanical loading. Cyclic high‐pressure torsion (CHPT) is one prosperous technique to synthesize low‐angle boundaries (LAGB) at the nanoscale, enabling the production of high‐strength materials. It is presented here with an in‐depth analysis of the structural evolution focusing on the effect of different strain amplitudes and accumulated strains as well as crystal structure to understand how these parameters need to be adjusted to optimize the fraction of LAGBs. Different than expected from classical fatigue testing, the crystal structure seems to play a minor role for the cell structure evolution at comparably large strain amplitudes. It is, therefore, a strong asset that CHPT is feasible to produce nanostructures LAGB boundaries in both FCC and BCC structures. Furthermore, by optimizing the geometry of the anvils, it enables homogenous structural sizes in the entire sample as in contrast to other techniques the strain gradient impact on LAGB formation can be overcome. [ABSTRACT FROM AUTHOR]

FeTi–Cu composites with varying Cu contents are subjected to high‐pressure torsion, and their deformation behavior is explored systematically using scanning electron microscopy, microhardness, and nanoindentation. The study identifies the limiting factors influencing the refinement during severe plastic deformation. The pronounced strength differences between phases lead to fragmentation primarily through hard–hard (FeTi–FeTi) contact points, promoted by homogeneous, i.e., nonlocalized, and possibly turbulent material flow. These conditions are prevalent in Cu‐rich composites and during high‐temperature deformation. Conversely, Cu‐lean composites exhibit deformation localization, hindering the fragmentation process. Abrasion becomes an efficient refinement mechanism at the submicron‐/nanoscale, particularly for composites containing higher concentrations of nanocrystalline FeTi and exhibiting homogeneous plastic deformation. Consequently, deformation localization in Cu‐lean composites inhibits both refinement mechanisms, while Cu‐rich compositions and higher temperatures result in efficient refinement but at the risk of coarsening at the nanoscale. Refinement is localization‐limited in the former case and abrasion‐limited in the latter. Optimized processing conditions can overcome these constraints, yielding a uniform nanocomposite. This study sheds light on the intricate interplay of the mechanical properties of the respective phases in a composite, emphasizing the importance of tailored compositions and deformation conditions to optimize nanocomposites, particularly when dealing with challenging material pairings. [ABSTRACT FROM AUTHOR]

The microstructure and texture are investigated for nanocrystalline Au‐13at%Pd deformed by high‐pressure torsion. The grain size of this alloy is observed to remain below about 20 nm when subjected to severe plastic deformation. Surprisingly, the initial <110> powder compaction texture does not change significantly during shearing. The results are explained in terms of a grain boundary sliding mechanism involving planar interfaces formed by grain boundary migration. [ABSTRACT FROM AUTHOR]

Background: X-linked hypophosphatemia (XLH) is a rare monogenetic skeletal disorder. Lower limb deformities contribute substantially to impaired gait quality and burden of disease in patients with XLH. Standardized data regarding onset and severity of lower limb maltorsion are unavailable. This study aimed to evaluate lower limb maltorsion using rotational magnetic resonance imaging (MRI) and computed tomography (CT). Methods: Rotational MRI and CT of children and adolescents with verified XLH were evaluated retrospectively. Femoral and tibial torsion, acetabular anteversion, and axial acetabular coverage were measured and compared with published age-adapted radiographic, clinical measurements and MRI data, respectively. Results: Fifteen patients (mean age, 10.7 years) were included in the study. Decreased femoral torsion was observed in 47% (14/30 femora) and femoral retrotorsion in 17% (5/30 femora). Ten of 13 hips with coxa vara deformity presented with decreased femoral antetorsion. Reduced external tibial torsion manifested in 64% (18/28 tibiae). Abnormal axial femoral head coverage was present in 67% (20/30 hips), whereas 53% (16/30 hips) showed increased acetabular anteversion. Conclusion: Femoral and tibial torsional pathologies were found in children and adolescents with XLH. The occurrence of severe femoral retrotorsion in a 2-year-old child prior to ambulation raises questions regarding the biomechanical impact of gait on the development of torsional deformities in XLH. [ABSTRACT FROM AUTHOR]

The sandpile group of a connected graph G, defined to be the torsion part of the cokernel of the graph Laplacian, is a subtle graph invariant with combinatorial, algebraic, and geometric descriptions. Extending and improving previous works on the sandpile group of hypercubes, we study the sandpile groups of the Cayley graphs of F 2 r , focusing on their poorly understood Sylow-2 component. We find the number of Sylow-2 cyclic factors for "generic" Cayley graphs and deduce a bound for the non-generic ones. Moreover, we provide a sharp upper bound for their largest Sylow-2 cyclic factors. In the case of hypercubes, we give exact formulae for the largest n–1 Sylow-2 cyclic factors. Some key ingredients of our work include the natural ring structure on these sandpile groups from representation theory, and calculation of the 2-adic valuations of binomial sums via the combinatorics of carries. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Veterinary Journal / Revue Vétérinaire Canadienne is the property of Canadian Veterinary Medical Association and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Realism about general relativity (GR) seems to imply realism about spacetime curvature. The existence of the teleparallel equivalent of general relativity (TEGR) calls this into question, for (a) TEGR is set in a torsionful but flat spacetime, and (b) TEGR is empirically equivalent to GR. Knox (Stud Hist Philos Sci Part B Stud Hist Philos Mod Phys 42(4):264–275, 2011) claims that there is no genuine underdetermination between GR and TEGR; we call this verdict into question by isolating and addressing her individual arguments. In addition, we anticipate and evaluate two further worries for realism about the torsionful spacetimes of TEGR, which we call the ‘problem of operationalisability’ and the ‘problem of visualisability’. [ABSTRACT FROM AUTHOR]

A 17‐year‐old patient with acute testicular pain had no blood flow observed on scrotal ultrasound Doppler on either side, suggestive of bilateral torsion. The patient underwent immediate scrotal surgical exploration, and a numerical anomaly was observed during surgery—there were two testicles on each side, and all four exhibited torsion. After detorsion, circulation was recovered, and three of four testicles were kept. One dystrophic testis was removed. [ABSTRACT FROM AUTHOR]

Let n = p r be a prime power ideal of F q [ T ] with r ≥ 2 . We study the rational torsion subgroup T (p r) of the Drinfeld modular Jacobian J 0 (p r) . We prove that the prime-to- q (q - 1) part of T (p r) is equal to that of the rational cuspidal divisor class group C (p r) of the Drinfeld modular curve X 0 (p r) . As we completely computed the structure of C (p r) , it also determines the structure of the prime-to- q (q - 1) part of T (p r) . [ABSTRACT FROM AUTHOR]

Silver selenide (Ag2Se) flexible films are promising near‐room‐temperature thermoelectric candidates for low‐grade heat harvesting. However, existing Ag2Se films are generally attached on substrates, which impedes further flexibility improvement of the films and constrains the scenarios of applications. Here a cost‐effective and scalable strategy is presented, which combines screen printing and annealing, for synthesizing freestanding Ag2Se inorganic films with different densities of pores. High‐density pores and thin thickness endow the films with high flexibility, while films with low‐density pores obtain higher power factor. Furthermore, by utilizing the porous microstructure, a composite structure consisting of a Ag2Se conductive network and an organic polydimethylsiloxane (PDMS) skeleton is fabricated, which further improves films’ stability under bending and torsion. Finally, a flexible thermoelectric generator comprising five Ag2Se/PDMS legs and encapsulated PDMS outputs a voltage of 20.2 mV and a maximum power of 810 nW (the corresponding power density is 5.4 W m−2) at a temperature difference of 30 K, verifying potential application at near room temperature. This work offers a useful paradigm for fabricating substrate‐free Ag2Se porous films with high flexibility for near‐room‐temperature thermoelectric applications. [ABSTRACT FROM AUTHOR]

In this article, a three‐dimensional (3D) auxetic system is designed by linking layers of rotating squares with torsion springs. The orientation of the rotating squares in the different layers is organized in such a way that when a tensile load is applied on them, corresponding squares would rotate in opposite directions. This creates a torque that acts on the torsion spring. As a consequence, the length of the torsion spring increases resulting in a negative Poisson's ratio in three dimensions. An analytical model for the Poisson's ratio is derived and then tested using a 3D‐printed specimen of the proposed design. The results are found to be in general good agreement. [ABSTRACT FROM AUTHOR]

Highlights In this paper, a universal mechanical model for the torsional behavior of fiber bundle was established, grounded in the principles of spatial geometry and continuum mechanics, incorporating differential geometry formulas. The model was validated through self‐designed experimental equipment and finite element simulations using Ansys Workbench, showing strong agreement between predicted torsional fracture behavior and experimental results. The study further examined the contributions of fiber bending, torsion, and tension to the overall torque, revealing that torsion plays the dominant role. Additionally, the effect of filament count on the torsional performance of fiber bundles was analyzed, demonstrating that while the number of fibers significantly influences stress distribution, its impact on overall torque is minimal. A universal mechanical model for fiber bundle torsional is proposed. High consistency between simulation and experimental results. Examined filament count effect on torsional strength. More filaments reduce stress concentration, improving performance. [ABSTRACT FROM AUTHOR]

Statistical shape modeling (SSM) offers the potential to describe the morphological differences in similar shapes using a compact number of variables. Its application in orthopedics is rapidly growing. In this study, an SSM of the intramedullary canal of the proximal femur was built, with the aim to better understanding the complexity of its shape which may, in turn, enhance the preoperative planning of total hip arthroplasty (THA). This includes the prediction of the prosthetic femoral version (PFV) which is known to be highly variable amongst patients who have undergone THA. The model was built on three dimensional (3D) models of 64 femoral canals which were generated from pelvic computed tomography images including the proximal femur in the field of view. Principal component analysis (PCA) was performed on the mean shape derived from the model and each segmented canal. Five prominent modes of variations representing approximately 84% of the total 3D variations in the population of shapes were found to capture variability in size, proximal torsion, intramedullary femoral anteversion, varus/valgus orientation, and distal femoral shaft twist/torsion, respectively. It was established that the intramedullary femoral canal is highly variable in its size, shape, and orientation between different subjects. PCA‐driven SSM is beneficial for identifying patterns and extracting valuable features of the femoral canal. [ABSTRACT FROM AUTHOR]

In this article, we study a certain Galois property of subextensions of k(Ators)$k(A_{\mathrm{tors}})$, the minimal field of definition of all torsion points of an abelian variety A$A$ defined over a number field k$k$. Concretely, we show that each subfield of k(Ators)$k(A_{\mathrm{tors}})$ that is Galois over k$k$ (of possibly infinite degree) and whose Galois group has finite exponent is contained in an abelian extension of some finite extension of k$k$. As an immediate corollary of this result and a theorem of Bombieri and Zannier, we deduce that each such field has the Northcott property, that is, does not contain any infinite set of algebraic numbers of bounded height. [ABSTRACT FROM AUTHOR]

The fiber-reinforced polymer (FRP) strengthening of reinforced concrete (RC) elements with torsional deficiencies has not yet been extensively studied. Existing studies have primarily focused on rectangular RC beams. The few studies on L or T-shaped beams have used open-form retrofitting methods. However, premature debonding of the retrofitting from concrete surfaces often leads to detachment before achieving enhanced torsional capacity. This study introduces an innovative application of closed-form FRP retrofitting for RC T-beams against torsion. Two novel closed-form torsional upgrading methods were proposed and investigated through a comprehensive experimental program involving eight large-scale T-beams. One method employs FRP ropes embedded in transverse grooves near the surface, while the other combines U-shaped EB-FRP strips with FRP ropes. Additionally, two configurations were examined replicating scenarios where the upper part of the slab is accessible or inaccessible. The results demonstrate that the closed-form methods improve torsional strength by 9% to 25% and twist at failure by 92% to 536% compared to unstrengthened beams, with beams retrofitting through the slab exhibiting superior performance. Step-by-step technical guidelines of the proposed methods are presented to minimize construction defects and ensure effective implementation in real RC structures. [ABSTRACT FROM AUTHOR]

In this study, high-pressure torsion (HPT) processing is applied to the as-cast Al0.5CoCrFeNi high-entropy alloy (HEA) for 1, 3, and 5 turns. Microstructural observations reveal a significant refinement of the second phase after HPT processing. This refinement effect is influenced by the number of processing turns and the distance of the processing position from the center. As the number of processing turns or the distance of the processing position from the center increases, the fragmentation effect on the second phase becomes more pronounced. The hardness of the alloy is greatly enhanced after HPT processing, but there is an upper limit to this enhancement. After increasing the number of processing turns to 5, the increase in hardness at the edge becomes less significant, while the overall hardness becomes more uniform. Additionally, the strength of the processed alloy is significantly enhanced, while its ductility undergoes a noticeable decrease. With an increase in the number of processing turns, the second phase is further refined, resulting in improvement of strength and ductility. [ABSTRACT FROM AUTHOR]

The subject of KCC theory is a second‐order ordinary differential equation, it is sometimes difficult to convert the high dimensional system into an equivalent second‐order system because of the analytical requirements of KCC theory. By means of the Euler‐Lagrange extension of a flow on a Riemannian manifold, this paper gives five geometric invariants of some three‐dimensional systems with great convenience, and focus on the analysis of two of them. The results show that the hyperbolic equilibria corresponding to the seven standard forms of three‐dimensional linear systems are Jacobi unstable. This is completely different from what we got before in two‐dimensional systems, where Jacobi stable and Jacobi unstable correspond to focus and node, respectively. All equilibria of classical Lü chaotic system and Yang‐Chen chaotic system are Jacobi unstable. Meanwhile, in three‐dimensional linear case, the torsion tensors at any point of the trajectory are identically equal to zero, but the two nonlinear systems have nonzero torsion tensors components. [ABSTRACT FROM AUTHOR]

The technology of manufacturing aluminum alloy workpieces using additive friction stir deposition (AFS‐D) has been thoroughly investigated. The ambiguous influence of deformation processing modes on the material density was found. Examination of the microstructure in the central zone of the specimens reveals the absence of microdefects typically associated with workpieces obtained through casting or powder metallurgy methods. It has been observed that the distribution of microhardness is significantly affected by the direction of specimen construction, with approximately a 20% difference in values between the periphery and the central part of the specimen. Specimens produced using the AFS‐D method exhibit a homogeneous microstructure characteristic of deformable aluminum alloys. Notably, a uniform distribution of intermetallides on the specimen surface has been identified. This outcome is likely a result of the alloy undergoing recrystallization during the severe plastic deformation process, leading to the formation of an ultradisperse structure. It is important to emphasize that the selection of technological parameters for AFS‐D should consider not only the magnitude of pressure and deformation but also the deformation speed. [ABSTRACT FROM AUTHOR]

Previous studies have compared the use of the Slocum- jig to the deformity reduction device (DRD) jig for the correction of distal femoral deformities of varying degrees in the frontal plane. The objective of the current study is to further investigate the use of the mini DRD jig in comparison to the Slocum jig for correction of varying degrees of torsional deformities of the distal femur. Femoral models (n = 60) were developed based on a CT scan of an approximately 16.5 kg normal canine femur. Models were created with a standard varus deformity of 15 degrees, and external torsional deformities of 15, 20, or 30 degrees. Using center of rotation of angulation (CORA) methodology, corrective osteotomies were planned and performed on each of the 3D printed models based on the group assigned. Modeling clay was applied the proximal femur to mimic visualization of a routine lateral surgical approach, while retaining the ability to palpate surgical landmarks. Post-correction anatomic lateral distal femoral angle (aLDFA) and femoral torsion angle (FTA) were measured and recorded. The mean post-correction FTA of groups using the DRD jig for correction were consistently closer to the ideal value compared to those using the Slocum jig, although these differences were not always statistically significant. Correction of external torsion between the DRD jig and the Slocum jig was significantly different in groups 1 and 2 (P = 0.026 and P = 0.046), but not in group 3. For the correction of varus deformity, no significant difference was found between the two jig types in any group. Results of this study suggest jig selection during distal femoral osteotomy for correction of torsional deformity may result in varying precision of post-correction alignment. Clinical significance of this variance remains unclear, and intra-operative visual assessment of alignment should be implemented to guide corrections. [ABSTRACT FROM AUTHOR]

Previous models of circular ring segment joints have been inadequate in describing their loading capacity due to the lack of consideration for the interaction between shear force and bending moment. Consequently, these models have led to over‐ or underestimation of the joints' capacity. The increasing use of dry joint connection technology in wind turbine towers and prefabricated segmental bridge constructions necessitates the development of advanced computational models for these connections. This study presents a new model that considers the effects of bending moment, shear force, and torsion on the loading capacity of circular ring segment joints. Numerical simulations were conducted to validate the developed model under different load combinations, and the results demonstrate excellent agreement between the model predictions and numerical simulations. [ABSTRACT FROM AUTHOR]

AbstractWe provide necessary and/or sufficient conditions for the stable Hom functors to be finitely presented. When the covariant Hom functor modulo projectives is finitely presented, its defect is isomorphic to the Bass torsion of the fixed argument. When the contravariant Hom functor modulo injectives is finitely presented, its defect is isomorphic to the cotorsion of the fixed argument. We also give a sufficient condition for the sub-stabilization of the tensor product to be finitely presented. A finite presentation of the tensor product leads to an unexpected application to injective modules. [ABSTRACT FROM AUTHOR]

In this paper, we have presented bulk viscous cosmological model of the universe in the modified gravity in which the Lagrangian of the gravitational action contains a general function F (T) , where T denotes torsion, for flat Friedmann–Robertson–Walker spacetime with isotropic fluid. We have studied cosmological solution in F (T) theory of gravity, especially of a particular preference F (T) = T + f (T) = (1 + γ) T + α T 2 , where γ and α are coupling constants, in the presence of bulk viscosity described by Eckart theory, Truncated Israel Stewart theory and Full Israel Stewart theory. The physical and geometrical prospectives of the models in Eckart, Truncated Israel Stewart theory and Full Israel Stewart theory are deliberated in details. The investigation of the variation of bulk viscous pressure, energy density, scale factor, Hubble parameter and deceleration parameter with cosmic growth is furnished in the relevant theories. The models are analyzed by comparison with recent observational data. The cosmological models are well-matched with observations. [ABSTRACT FROM AUTHOR]

The subgroup G ≤ A is absolute direct summand (ADS) if, for every G -high subgroup H ≤ A (i.e. maximal with respect to the property G ∩ H = 0), we have A = G ⊕ H , and A itself is an ADS group if all of its summands inherit this property. In this paper, we characterize the structure of ADS abelian groups, which can be defined as groups such that members of the decomposition into two direct summands are mutually injective. In particular, an ADS abelian group is either divisible, or a direct sum of an indecomposable torsion-free group and a divisible torsion group, or a torsion group such that each p -component is a direct sum of cyclic p -groups of the same length or of Prüfer groups. [ABSTRACT FROM AUTHOR]

This study investigates the impact of exposure to aggressive environments, specifically saline conditions per ASTM B117 standard, on the shear strength of adhesive‐bonded joints, crucial for ensuring structural integrity in various industrial applications like automotive, aerospace, and construction. Using an epoxy‐based adhesive to bond AISI304 steel, specimens undergo 14‐ and 28‐day salt spray treatments to simulate harsh working conditions. Torsional shear strength assessment of steel‐to‐steel adhesive joints is conducted using a torsion test methodology, with an analytical approach used to extrapolate adhesive joint shear strength. This research contributes to understanding adhesively bonded joint performance in challenging environmental conditions, and how the shear strength of the bonded joints changes in relatively small amount of time, offering valuable insights for robust structural designs across industrial sectors. [ABSTRACT FROM AUTHOR]

Let Λ be a finite-dimensional algebra over a field. We describe how Buan and Marsh’s τ-exceptional sequences can be used to give a “brick labeling” of a certain poset of wide subcategories of finitely generated Λ-modules. When Λ is representation-directed, we prove that there exists a total order on the set of bricks which makes this into an EL-labeling. Motivated by the connection between classical exceptional sequences and noncrossing partitions, we then turn toward the study of (well-separated) completely semidistributive lattices. Such lattices come equipped with a bijection between their completely join-irreducible and completely meet-irreducible elements, known as rowmotion or the “κ-map.” Generalizing known results for finite semidistributive lattices, we show that the κ-map determines exactly when a set of completely join-irreducible elements forms a “canonical join representation.” A consequence is that the corresponding “canonical join complex” is a flag simplicial complex, as has been shown for finite semidistributive lattices and lattices of torsion classes. Finally, we demonstrate how Jasso’s τ-tilting reduction of finite-dimensional algebras can be encoded using the κ-map. We use this to define κd-exceptional sequences for finite semidistributive lattices. These are distinguished sequences of completely join-irreducible elements which we prove specialize to τ-exceptional sequences in the algebra setting. [ABSTRACT FROM AUTHOR]

This work introduces a geometrical object that generalizes the quantum geometric tensor; we call it N -bein. Analogous to the vielbein (orthonormal frame) used in the Cartan formalism, the N -bein behaves like a 'square root' of the quantum geometric tensor. Using it, we present a quantum geometric tensor of two states that measures the possibility of moving from one state to another after two consecutive parameter variations. This new tensor determines the commutativity of such variations through its anti-symmetric part. In addition, we define a connection different from the Berry connection, and combining it with the N -bein allows us to introduce a notion of torsion and curvature à la Cartan that satisfies the Bianchi identities. Moreover, the torsion coincides with the anti-symmetric part of the two-state quantum geometric tensor previously mentioned, and thus, it is related to the commutativity of the parameter variations. We also describe our formalism using differential forms and discuss the possible physical interpretations of the new geometrical objects. Furthermore, we define different gauge invariants constructed from the geometrical quantities introduced in this work, resulting in new physical observables. Finally, we present two examples to illustrate these concepts: a harmonic oscillator and a generalized oscillator, both immersed in an electric field. We found that the new tensors quantify correlations between quantum states that were unavailable by other methods. [ABSTRACT FROM AUTHOR]

The aim of this paper is to apply the framework developed by Sam and Snowden to study structural properties of graph homologies, in the spirit of Ramos, Miyata and Proudfoot. Our main results concern the magnitude homology of graphs introduced by Hepworth and Willerton, and we prove that it is a finitely generated functor (on graphs of bounded genus). More precisely, for graphs of bounded genus, we prove that magnitude cohomology, in each homological degree, has rank which grows at most polynomially in the number of vertices, and that its torsion is bounded. As a consequence, we obtain analogous results for path homology of (undirected) graphs. [ABSTRACT FROM AUTHOR]

In the present study, twinning-induced plasticity (TWIP) steels with varying grain size and distribution were obtained by adjusting the thermomechanical methods such as pre-torsion, pre-strain and heat treatment. The advantage of gradient structure design over traditional grain refinement lies in its ability to optimize material strength while reducing ductility loss. Furthermore, the hydrogen embrittlement (HE) behavior of TWIP steels with various grain sizes and distributions was investigated under in-situ hydrogen charging conditions. The results revealed that the gradient structural specimen with finer equiaxed grains in the edge region exhibited lower lattice distortion, fewer stress concentration points and delayed plastic deformation. This decelerated the initiation and propagation of cracks, thus optimizing HE resistance and demonstrating comprehensive mechanical properties superior to all the other investigated specimens in the hydrogen environment. [Display omitted] • Quasi in-situ observation of deformation characteristics. • Gradient design can make steels have superior comprehensive mechanical properties. • Gradient structural materials exhibit the good HE resistance. • In-situ hydrogen charging is more likely to cause HE vs hydrogen pre-charging. • Grain refinement can improve HE resistance. [ABSTRACT FROM AUTHOR]