Search Results (132)

Background and Clinical Significance: Treatment options for chronic type B aortic dissections (TBADs) remain a topic of ongoing debate. Patients with post-dissection thoracoabdominal aortic aneurysms (PD-TAAAs) are typically younger than those with degenerative TAAAs, and their aortas undergo continuous remodeling over their lifetime. Fenestrated/branched endovascular aortic repair (F/B-EVAR) has shown promising results, but it can be challenged by the presence of a narrow true lumen, which hinders navigation and deployment of bridging components. Moreover, the presence of patent segmental arteries originating from the false lumen may prevent aneurysm shrinkage due to persistent flow, which may also result in insufficient spinal cord protection strategies and an increased risk of spinal cord ischemia. Consequently, multiple endovascular interventions are often necessary to address the persistent anatomical changes in these patients. Case Presentation: We present the case of a patient affected by a post-dissecting TAAA who underwent multiple open and endovascular treatment attempts. The presence of prior multiple laparotomies discouraged a new open surgical repair, while the hypertrophic segmental arteries and the presence of a narrow true lumen made standard F/B-EVAR unfeasible. The patient was successfully treated using a combination of different adjunctive advanced endovascular techniques, including minimally invasive segmental artery coil embolization (MiSACE) as a spinal cord preconditioning strategy and prevention of type II endoleak. Moreover, transcatheter electrosurgical septotomy (TES) was used to create a single aortic channel in the presence of a narrow true lumen, which allowed the deployment of a multifeatured, custom-made branched endograft. Conclusions: Endovascular repair of post-dissection TAAAs requires a thorough understanding of advanced endovascular adjuncts, which are often combined to overcome the complex anatomical challenges inherent to this disease. Although encouraging results have been reported, both segmental artery embolization for the indications described here and TES warrant further evaluation in prospective multicenter studies to confirm their safety and efficacy. Full article

This survey presents an overview of recent developments in the analysis and numerical treatment of spectral fractional diffusion equations. Particular attention is devoted to efficient strategies for solving spectral fractional diffusion problems, including approaches based on rational approximation that enable efficient numerical realization of fractional powers of elliptic operators. Building on these approximations, we discuss adaptive finite element discretization techniques for polygonal domains, where singularities and geometric irregularities require carefully designed mesh refinement strategies. The survey also highlights the role of fractional diffusion operators in the preconditioning of coupled and multiphysics problems, where they can significantly improve the robustness and convergence of iterative solvers. Furthermore, we review recent results on maximum principles and monotonicity preservation for spectral fractional diffusion–reaction equations, which are essential for ensuring physically meaningful numerical solutions. Finally, we discuss current efforts aimed at improving robustness and computational efficiency through reduced and multilevel iteration methods. These approaches provide scalable algorithms for large-scale problems while maintaining accuracy and stability. The survey concludes by outlining several open problems and promising directions for future research in the numerical analysis of fractional diffusion models. Full article

The mining industry is in need of automation due to increasing requirements like higher global demands for resources and deposits, which are deeper and more complex. Progressing underground mines lead to longer travel times to the mining face and thus a loss in productive working time, which has to be compensated by automation. Ultimately, stricter health and safety regulations and a decreasing number of skilled operators accelerate the need for automation further. Within the the drill-and-blast cycle in underground mining, the drilling of blast holes is a central step. While semi-automated and supporting systems exist that allow the automated execution of single process steps under supervision, to date, no system is available for the unsupervised blast hole drilling of a mine face. A precondition for unsupervised operation is a perception system, which allows independent decision-making of the machine. To address this gap, this work presents a novel vision system capable of segmenting a mine face into drillable and non-drillable areas, which can serve as the basis for the autonomous adaption of a drilling pattern. An area of the mine face is considered drillable if no leftover blast holes from the previous blast cycle are present and the surface angle is below a certain threshold. The system presented is based on a stereo camera setup mounted on a drill jumbo. The resulting 2D and 3D data are processed by software that employs AI-based computer vision techniques, as well as traditional algorithms. The system was validated, and the performance was verified in the K+S Zielitz mine. Experts assisted in the determination of operational parameters and empirically validated the system’s performance. Additionally, the blast hole detection algorithm underwent a data-based analytical verification. Full article

Compact carbonate stones are widely used in architectural heritage for their aesthetic value and cultural significance, yet their long-term durability in saline environments remains insufficiently understood, particularly when assessed using standard salt crystallization tests developed primarily for porous lithotypes. This study investigates salt-induced deterioration in Portoro limestone, a compact ornamental carbonate extensively employed in historic architecture, considering four commercial varieties representative of heritage applications. Salt crystallization tests were performed using saturated sodium sulphate (Na₂SO₄) and sodium chloride (NaCl) solutions following the relevant European standard procedure, with the protocol extended to 45 cycles to capture delayed deterioration processes. Both untreated specimens and samples subjected to controlled thermal pre-conditioning at 300 °C and 500 °C were tested to activate latent microstructural weaknesses. Material decay was assessed through mass variation, porosity changes, surface observations, Leeb rebound hardness and ultrasonic pulse velocity measurements. Results demonstrate that deterioration is primarily controlled by salt type and microstructural characteristics rather than by total porosity. Sodium sulphate induced severe internal damage and abrupt structural failure associated with mirabilite crystallization, often following a prolonged phase of apparent stability. In contrast, sodium chloride causes mainly superficial effects with negligible mechanical impact. Thermal pre-conditioning accelerated damage development, while non-destructive techniques revealed internal deterioration well before visible damage occurred. These findings indicate that standard crystallization tests may be inadequate for low-porosity stones and that extended-cycle approaches provide a more reliable framework for durability assessment in saline environments. Full article

Recently, a growing number of scientific research and clinical studies have demonstrated the potential of extracellular vesicles (EVs) secreted by cells of different types for treating various diseases. It was shown that most frequently, substances and molecules excreted by the cells exert therapeutic or other effects, and not the cells themselves. Their cargo is wrapped in membrane envelopes, allowing it to survive for a longer time and find targets in organs and tissues as well as overcome various barriers, including the blood–brain barrier. EVs from mesenchymal stromal (stem) cells (MSCs) have attracted particular interest, as MSCs possess immunomodulatory and tissue-repairing properties per se. However, their clinical use is severely limited due to the frequent lack of efficiency in clinical trials, as well as existing risks of tumorigenesis and pulmonary embolism. EVs isolated from MSCs may help circumvent these problems, but their composition and properties, like those of their progenitors, vary significantly between batches, owing to donor characteristics and cell culture conditions. EVs from immortalized MSCs offer greater potential for repeatability and uniformity but raise the question of whether cell immortalization products enter EVs and are transferred to target cells and/or affect them. This review examines the most recent data on preconditioning techniques for MSC-derived EVs, EV characterization, large-scale manufacturing, storage, and the use of EVs from immortalized MSCs, including their characteristics and therapeutic properties, with a special emphasis on safety issues. Full article

This article examines Khotan’s role in the transmission and reception of Avataṃsaka/Huayan Buddhism, arguing that the Buddhāvataṃsaka-sūtra’s exceptional prestige and royal protection in Khotan provided favourable conditions for the circulation—and possibly the redaction—of large Mahāyāna compilations. It then analyses two Avataṃsaka-group meditation texts translated by the Khotanese monk Devendraprajñā (The Section on the Cultivation of Loving-Kindness and The Section on the Inconceivable Buddha-Realm), showing how they combine Huayan cosmology and non-obstruction with visualization-based contemplative techniques. Finally, by reading these texts alongside The Mahāyāna Sūtra on the Merits of Creating Images Spoken by the Buddha, the article highlights a functional differentiation within Khotanese practice: the meditation texts prioritise cognitive and visionary transformation and largely omit formal repentance, whereas the image-making sūtra explicitly requires repentance as a precondition for karmic purification, promising the elimination or mitigation of karmic consequences through the making of Buddha images. Full article

With the continuous development of cities and the increasing utilization of underground space, ambient noise seismic imaging has become an essential approach for exploring and monitoring the urban subsurface. The integration of Distributed Acoustic Sensing (DAS) with ambient noise imaging offers a more convenient and effective solution for investigating shallow subsurface structures in urban environments. To overcome the limitations of conventional ambient noise seismic nodes, which are costly and incapable of achieving high-density data acquisition, this work makes use of existing urban telecommunication fibers to record ambient noise and perform sliding-window cross-correlation on it. Then the Phase-Weighted Stack (PWS) technique is applied to enhance the quality and stability of the cross-correlation signals, and fundamental-mode Rayleigh wave dispersion curves are extracted from the cross-correlation functions through the High-Resolution Linear Radon Transform (HRLRT). In the inversion stage, an adaptive regularization strategy based on automatic L-curve corner detection is introduced, which, in combination with the Preconditioned Steepest Descent (PSD) method, enables efficient and automated dispersion inversion, resulting in a well-resolved near-surface S-wave velocity structure. The results indicate that the proposed workflow can extract useful surface-wave dispersion information under typical urban noise conditions, achieving a feasible level of subsurface velocity imaging and providing a practical technical means for urban underground space exploration and utilization. Full article

Static cold storage (SCS) remains the most widely used method of liver graft preservation due to its simplicity, accessibility, and reduced cost in transplantation practice. Since the invention of the University of Wisconsin (UW) solution, several alternative preservation solutions—including histidine–tryptophan–ketoglutarate (HTK), Celsior, and more recently IGL-1 and IGL-2—have been formulated to optimize cellular and vascular protection during cold ischemia. More recently, the introduction of dynamic perfusion techniques, such as hypothermic oxygenated perfusion (HOPE) and normothermic machine perfusion (NMP), approximately fifteen years ago, has further enhanced transplantation protocols, being applied either alone or in combination with traditional SCS to ensure optimal graft preservation prior to implantation. Despite these technological advances, achieving fully effective dynamic perfusion remains a key challenge for improving outcomes in vulnerable grafts, particularly steatotic or marginal livers. This review details how Polyethylene Glycol 35 (PEG35)-based solutions activate multiple cytoprotective pathways during SCS, including AMP-activated protein kinase (AMPK), nitric oxide (NO) production, and the antioxidant transcription factor Nrf2. We propose that these molecular mechanisms serve as a form of preconditioning that is synergistically leveraged by HOPE to preserve mitochondrial function, endothelial glycocalyx integrity, and microvascular homeostasis. Furthermore, the oncotic and rheological properties of PEG35 reduce perfusate viscosity, mitigating shear stress and microcirculatory damage during dynamic perfusion—effects that are further enhanced by NO- and AMPK-mediated protection initiated during the SCS phase. This integrated approach provides a strong rationale for combining PEG35-mediated SCS with HOPE, particularly for grafts with high susceptibility to ischemia–reperfusion injury, such as fatty livers. Finally, we highlight emerging avenues in graft preservation, including the design of unified perfusion solutions that optimize endothelial, mitochondrial, and redox protection, with the potential to improve post-transplant outcomes and extend applicability to other solid organ grafts. Full article

Background/Objectives: As bioactive extracellular vesicles, exosomes participate in cellular communication and disease mechanisms, yet their structural complexity continues to challenge standard analytical methodologies. This review summarizes published studies reporting exosome concentrations in human plasma, serum, and platelet-rich plasma from healthy individuals and highlights methodological differences. Methods: A comprehensive PubMed search (1986–31 August 2025) was performed using terms related to exosomes and their quantification, excluding cancer- and disease-related studies. Eligible articles reported exosome concentrations in plasma, serum, or platelet-rich plasma using particle-counting techniques such as nanoparticle tracking analysis, flow cytometry, or tunable resistive pulse sensing. Results: Twenty-two articles, including 167 healthy donors, met the inclusion criteria. The following mean concentration ranges were reported: plasma (n = 18), ranged from 4.50 × 10⁸ to 6.70 × 10¹¹ particles/mL with differences by quantification method; serum (n = 10), from 5.30 × 10⁸ to 2.13 × 10¹¹ particles/mL; non-activated platelet-rich plasma (n = 1), 7.52 × 10⁹ particles/mL; activated platelet-rich plasma (n = 3), 4.87 × 10¹⁰ to 7.16 × 10¹⁰ particles/mL; and preconditioned platelet-rich plasma with photothermal biomodulation (n = 2), 2.53 × 10¹¹ to 2.99 × 10¹¹ particles/mL. Conclusions: Isolation and quantification methods exhibit high variability, which strongly influences the overall quantity and quality of the exosomes obtained. Characteristics, including cargo composition, purity, and exosome integrity, must be considered when developing validated methods. Furthermore, emerging evidence suggests that PTBM preconditioning can increase exosome release from cells. In summary, rigorous standardization of protocols is essential to advance the scientific understanding and the clinical potential of exosome-based therapies. Full article

This paper presents a new Residual-based Sparse Approximate Inverse algorithm, designed to be automatic, computationally efficient, and highly parallelizable. After briefly reviewing Frobenius-norm-based preconditioning techniques and identifying two key challenges in this class of methods, we introduce an improved approach that integrates adaptive strategies from the Power Sparse Approximate Inverse algorithm and incomplete LU factorization. The method leverages the Hamilton–Cayley theorem for effective sparsity pattern construction and employs LU decomposition for efficient implementation. Theoretical analysis establishes the convergence properties and computational features of the proposed algorithm. Numerical experiments using real-world data demonstrate that the proposed algorithm significantly outperforms established methods—including the Sparse Approximate Inverse, Power Sparse Approximate Inverse and Residual-based Sparse Approximate Inverse algorithms—with a Generalized Minimal Residual iterative solver, confirming its superior efficiency and practical applicability. Full article

Background: Evidence regarding the effects of twisting hamstring tendons on graft properties in anterior cruciate ligament (ACL) reconstruction remains controversial. The objective of this study was to evaluate the influence of a 180° twist on the tensile properties of human hamstring tendon grafts (HTGs). Methods: Fourteen human cadavers were included, and hamstring tendons (semitendinosus [ST] and gracilis [GR]) were harvested bilaterally. Matched pairs of tendons were allocated to the ST and GR groups and further subdivided into control (ST-0, GR-0) and experimental (ST-180, GR-180) subgroups. Standard tripled single-tendon grafts were prepared in the control groups, while grafts in the experimental groups were twisted by 180°. All grafts were preconditioned and tested using a universal testing machine (Shimadzu AGS-X, Shimadzu Corporation, Japan) to determine tensile strength, stiffness, tensile modulus, and energy absorption capacity. Results: In the semitendinosus group, the maximum force was 648.72 (±287.71) N for ST-0 and 853.11 (±189.14) N for ST-180, with energy absorption capacities of 9.21 (±4.47) J and 13.48 (±4.95) J, respectively. Although the mean values of the investigated parameters were consistently higher in the ST-180 group, these differences did not reach statistical significance. In the gracilis group, no statistically significant differences were observed between the GR-0 and GR-180 subgroups for any parameter. Conclusions: Twisting hamstring tendons by 180° during graft preparation results in limited alterations of biomechanical properties, without statistically significant improvements. These findings call into question the clinical relevance of this technique in enhancing graft material properties for ACL reconstruction. Full article

Background: Endometrosis is a prevalent fibrotic condition in mares that impairs reproductive efficiency by inducing transdifferentiation of endometrial stromal cells into myofibroblasts, leading to excessive ECM deposition. Methods: To elucidate the molecular mechanisms underlying fibrosis resolution, this study employed comprehensive proteomic techniques, including LC-MS/MS and SILAC, to analyze the interaction between myofibroblasts and mesenchymal stem cells derived from the endometrium (ET-eMSCs) preconditioned with PGE₂. An in vitro co-culture system was used, with samples collected at baseline and after 48 h. Results: Proteomic analysis identified significant alterations in proteins associated with ECM remodeling, immune regulation, and cellular stress response. Notably, proteins involved in collagen degradation, antioxidant defense, and growth factor signaling pathways were differentially abundant. Network analyses demonstrated robust interactions among these proteins, suggesting coordinated modulatory effects. The data indicate that PGE₂-primed ET-eMSCs induce a shift in myofibroblast secretory profiles, promoting a reduction in ECM stiffness, tissue reorganization, and activation of resolution pathways. Data are available via ProteomeXchange with identifier PXD067551. Conclusions: These findings reinforce the therapeutic potential of mesenchymal stem cell-based interventions for fibrotic diseases of the endometrium, opening avenues for regenerative strategies to restore reproductive function in mares. Full article

Facing challenges of low efficiency and severe wear in deep hard formations with conventional drilling bits, this study investigates the synergistic rock-breaking technology combining a pulsed CO₂ laser with mechanical bits. The background highlights the need for novel methods to enhance drilling speed in high-strength, abrasive strata where traditional bits struggle. The theoretical analysis explores the thermo-mechanical coupling mechanism, where pulsed laser irradiation rapidly heats the rock surface, inducing thermal stress cracks, micro-spallation, and strength reduction through mechanisms like mineral thermal expansion mismatch and pore fluid vaporization. This pre-damage layer facilitates subsequent mechanical fragmentation. The research employs finite element numerical simulations (using COMSOL Multiphysics with an HJC constitutive model and damage evolution criteria) to model the coupled laser–mechanical–rock interaction, capturing temperature fields, stress distribution, crack propagation, and assessing efficiency. The results demonstrate that laser pre-conditioning significantly achieves 90–120% higher penetration rates compared to mechanical-only drilling. The dominant spallation mechanism proves energy-efficient. Conclusions affirm the feasibility and significant potential of CO₂ laser-assisted drilling for deep formations, contingent on optimized laser parameters, composite bit design (incorporating laser transmission, multi-head layout, and environmental protection), and addressing challenges, like high in-situ stress and drilling fluid interference through techniques like gas drilling. Future work should focus on high-power laser downhole transmission, adaptive control, and rigorous field validation. Full article

Palatability is a critical determinant of pet food performance, directly influencing voluntary intake, nutrient utilization, and therapeutic efficacy. In this systematic review, we examine peer-reviewed research publications, patent filings, and commercial product data pertaining to palatant technologies in dry and wet pet food from 2014 to 2024. Major palatant classes—including fats, proteins, yeast extracts, and novel plant-derived or insect-based hydrolysates—are evaluated for their physicochemical properties, flavor-release mechanisms, and stability during processing. We analyze formulation techniques such as microencapsulation, Maillard-reaction enhancement, and multilayer coating systems, focusing on their impact on aromatic compound retention and palatability consistency. Patent landscape assessment identifies over 15 key innovations in delivery systems, life-stage-specific palatant modulation, and dual-phase release architectures. Dual-phase release architectures are defined as systems that deliver active compounds in two sequential phases, such as immediate and sustained release. Sensory evaluation methodologies—ranging from multivariate preference mapping to descriptive analysis—are critically appraised to correlate human-panel metrics with canine and feline feeding behavior. We also discuss strategic integration of palatants at different processing stages (pre-conditioning, extrusion, and post-extrusion) and the challenges of balancing taste masking with nutritional requirements, particularly in formulations containing alternative proteins for sustainability. Despite rapid market growth in functional palatant-infused products, peer-reviewed literature remains relatively limited, suggesting opportunities for further research on species-specific flavor drivers, synbiotic flavor–nutrient interactions, and novel delivery platforms. This comprehensive overview of palatant science, patent innovations, and market evolution provides evidence-based guidance for researchers, formulators, and veterinarians seeking to optimize organoleptic properties and consumer acceptance of next-generation pet foods. Full article

In response to increasing sustainability demands, the packaging industry is shifting toward paper-based alternatives to replace polymer packaging. However, achieving complex, three-dimensional geometries comparable to plastics remains challenging due to the limited stretchability of paper. This study investigates advanced preconditioning techniques to enhance the formability of paper materials for deep-draw packaging applications. A custom-built test rig was developed at Syntegon Technology GmbH to systematically evaluate the effects of ultrasound-assisted moistening and segmented radiative heating. Under optimized conditions, 2.67 s moistening, 70.00 °C punch temperature, and 2999 W radiation power, maximum stretchability increased from 13.00% to 26.93%. The results confirm the effectiveness of ultrasound in accelerating moisture uptake and radiation heating in achieving uniform thermal distribution across the paper substrate. Although prototype constraints, such as the absence of inline conditioning and real-time measurement, limit process stability and scalability, the findings provide a strong foundation for developing industrial 3D paper forming processes that support sustainable packaging innovation. Full article