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Article
Computer Science and Mathematics
Computer Networks and Communications

Clarissa Astuto

,

Daniele Francesco Santamaria

Abstract: Self-regulated transportation networks belong to the class of continuous network models and are widely used not only in biological applications, such as vascular systems, neural networks or tissues regeneration but also in urban infrastructure and in communication technologies. Their well-established tree structure prevents the formation of loops, which limits their ability to capture an important feature observed in real systems: when a disruption or damage occurs, the network should be able to reorganize to restore transport pathways. In this work, we propose alternative modeling strategies to incorporate this capability. These approaches allow the network to adapt to perturbations by modifying its structure and, in some cases, by creating alternative routes that compensate for damaged regions. Numerical results illustrate how the modified models can reproduce self-repair mechanisms that are not captured by standard formulations.

Article
Environmental and Earth Sciences
Soil Science

Zhengrong Bao

,

Changbo Ji

,

Wanning Dai

,

Xiao Liang

,

Chunlian Wang

,

Zunqi Liu

,

Jun Meng

Abstract:

To investigate the effects of long-term biochar application on different forms of potassium (K) content in maize rhizosphere soil and maize growth, two biochar application rates (B0: 0 t ha⁻¹ yr⁻¹, B1: 2.625 t ha⁻¹ yr⁻¹) and two K fertilizer application rates (K0: 0 kg ha⁻¹ yr⁻¹, K1: 60 kg ha⁻¹ yr⁻¹) to create four treatments (B0K0, B0K1, B1K0, B1K1). In this long-term field trial, we investigated various forms of K in the maize rhizosphere soil, together with soil physicochemical properties and maize growth indicators. Results indicate that biochar significantly increased microbial biomass carbon (MBC), cation exchange capacity (CEC), and electrical conductivity (EC) in the rhizosphere soil, while also improving rhizosphere soil pH. Compared with the treatment without biochar, biochar application significantly increased the content of water-soluble potassium (WSK), exchangeable potassium (EK), and non-exchangeable potassium (NEK) in the rhizosphere soil by 18.57% (2021) and 11.18% (2022), 13.49% (2021), and 11.43% (2022), 14.65% (2021), and 17.06% (2022), respectively. Maize roots were more developed, and plant height, stem diameter, and leaf area index were significantly increased. With above-ground dry weight and K uptake significantly increasing by 13.87% (2021) and 12.04% (2022), and 41.84% (2021) and 43.87% (2022), respectively. Compared with B0K0, the B1K1 treatment—which combined biochar with K fertilizer—exhibited the highest K content in all forms within the rhizosphere soil, along with the greatest maize aboveground dry weight and K uptake. This study demonstrates biochar’s potential in meeting crop root K demands, laying the foundation for its application in enhancing soil K fertility.

Article
Engineering
Electrical and Electronic Engineering

Antonio Carlos Bento

,

Carlos Vazquez-Hurtado

Abstract: The high cost and complexity of Industry 4.0 laboratory infrastructure limit the adoption of Digital Twin concepts in engineering education. This paper proposes a low-cost Digital Twin framework for sustainable manufacturing education integrating SAP NetWeaver, Node-RED, and AI-based decision support. The framework adopts a layered architecture that connects PLC-based simulation, IoT middleware, enterprise resource planning systems, and intelligent decision-making components. Node-RED enables real-time data exchange, while SAP NetWeaver provides enterprise-level integration through OData services. An AI module supports decision-making for production and inventory management. The proposed framework is implemented as a functional prototype, demonstrating end-to-end integration without requiring physical manufacturing equipment. Competency-based mapping aligns the framework with Industry 4.0 engineering skills, supporting its use in academic environments. A sustainability assessment highlights reductions in infrastructure cost, energy consumption, and resource usage compared to traditional laboratory approaches. The results indicate that the framework provides a scalable and accessible solution for teaching Digital Twin concepts, contributing to sustainable engineering education in resource-constrained contexts.

Article
Physical Sciences
Other

Ramón Serrano Montesinos

,

Joan Josep Ferrando

,

Juan Antonio Morales-Lladosa

Abstract: A covariant formulation of the Geometric Dilution of Precision (GDOP) matrix is presented in the framework of a Relativistic Positioning System (RPS). By including the receiver-emitter frequency ratios, the Frequency Geometric Dilution of Precision (FGDOP) scalar is computed in terms of observable quantities, the received frequencies and the angular separation between pairs of emitters in view. Some required concepts are first introduced: the FGDOP matrix and the Gram matrix associated to k light-like vectors. From the tensor form of the FGDOP matrix and its trace, a closed form of the FGDOP scalar is obtained, extending previous matrix calculations. Clarifying computations for symmetric emitter configurations are presented. The geometric interpretation of the GDOP scalar in terms of volumes and areas defined by the relative position of the emitters on the unit celestial sphere of the user is also recovered.

Article
Computer Science and Mathematics
Algebra and Number Theory

Ebrahim E. Elsayed

Abstract: ZPIF (Zero Pair Interaction Functional) is introduced as a quadratic spectral operator framework extending the classical explicit formula of the Riemann zeta function. Unlike the standard linear spectral decomposition, ZPIF incorporates second-order interactions between spectral modes within a Hilbert space formulation. The framework includes a rigorous operator definition, spectral expansion, trace-class regularization, and conditional convergence under truncation. A computational scheme based on numerical zeta zeros is also proposed. The novelty of ZPIF lies in introducing a quadratic spectral energy functional consistent with classical spectral heuristics without assuming unresolved conjectures. Numerical experiments demonstrate nonlinear growth behavior and quadratic interaction effects that are absent in classical linear formulations.

Article
Biology and Life Sciences
Agricultural Science and Agronomy

Santo Orlando

,

Fabrizio Colverde

,

Carlo Greco

,

Pietro Catania

,

Mariangela Vallone

,

Michele Massimo Mammano

Abstract: This study evaluates the performance of LiDAR sensing and UAV photogrammetry for three-dimensional canopy reconstruction and structural parameter estimation in precision agriculture. Experiments were conducted in Sicily (Italy) on Moringa oleifera Lam. and Ficus macrophylla subsp. columnaris, representing contrasting canopy architectures. LiDAR and UAV data were used to generate canopy models and estimate canopy height, volume, and vegetation density. A voxel-based approach was applied to LiDAR point clouds to analyze internal canopy structure. LiDAR significantly outperformed UAV photogrammetry, achieving lower errors in canopy height estimation (RMSE = 0.19–0.21 m vs. 0.52–0.60 m) and canopy volume (3.5–4.2% vs. 13.7–16.1%). UAV photogrammetry provided reliable estimates of canopy surface but underestimated structural parameters in dense vegetation due to occlusion effects. Differences were more pronounced in Ficus macrophylla than in Moringa oleifera, highlighting the influence of canopy complexity. These findings demonstrate that LiDAR-derived structural metrics can improve canopy characterization and support precision agriculture applications such as biomass estimation, irrigation planning, and canopy management in Mediterranean cropping systems.

Article
Physical Sciences
Optics and Photonics

P.B. Parchinsky

,

A.A. Nasirov

,

Sh. U. Yuldashev

,

A. Arslanov

,

R.A. Nusretov

,

N.A. Kulagina

,

S. Kh. Suleymanov

,

Peng Li

,

Sergei A. Khakhomov

,

Alina V. Semchenko

+3 authors

Abstract: This study investigates the effect of co-doping with nanographene on the properties of FTO layers produced by spray pyrolysis. The results show that co-doping with nanographene enhances phase separation processes within the bulk of the FTO layer. The inhomogeneities formed during phase separation are depleted of fluorine compared to the film bulk. Co-doping with nanographene also significantly modifies the optical properties of the FTO layers. Specifically, it alters the position and intensity of the peaks in the reflection spectra, indicating a change in the nature of the absorbing centers. Furthermore, the optical bandgap of the FTO layers decreases with an increasing degree of nanographene doping. Finally, co-doping with nanographene reduces the resistance of the FTO layers, which can be attributed to an increase in charge carrier mobility.

Review
Medicine and Pharmacology
Urology and Nephrology

Giuseppe Seminara

,

Leonardo Meduri

,

Marco Leuzzi

,

Gabriele Antonini

,

Antonio Aversa

Abstract: Background/Objectives: Penile rehabilitation (PR) techniques are claimed to counteract chronic degenerative processes of cavernous tissue such as penile hypoxia, neurovascular damage, and cavernous fibrosis. The objective of this umbrella review is to synthesize findings from existing meta-analyses to evaluate the efficacy of traditional and emerging PR strategies, providing an evidence-based roadmap for clinical management after surgery for prostate cancer. Methods: Conducted in accordance with PRIOR guidelines, a comprehensive literature search of PubMed, The Cochrane Library, and Scopus was performed through April 2026. The review included primarily systematic reviews and meta-analyses investigating pharmacological, physical, surgical, and regenerative interventions for post-prostatectomy erectile dysfunction (ED). Methodological quality was independently assessed using standardized tools. Results: PDE5 inhibitors (PDE5-is) significantly improve erectile function during active treatment, yet evidence supporting their role in promoting spontaneous, "unassisted" recovery remains limited. Vacuum erectile devices demonstrate high efficacy for assisted intercourse but show minimal impact on returning to baseline function compared to placebo. Penile prosthesis (PP) implantation maintains robust efficacy with exceptionally high satisfaction rates (83–85%), proving independent of prior pelvic surgery. Although early-phase trials suggest clinical potential for regenerative therapies like low-intensity extracorporeal shockwave therapy, platelet-rich plasma, and stem cell interventions, the evidence is currently undermined by substantial heterogeneity in study protocols and concerns regarding methodological quality. Conclusions: PR following radical prostatectomy remains a complex challenge characterized by poor evidence. While PDE5-Is are established first-line therapy for assisted function, PP remains the most reliable definitive treatment for refractory ED cases. Regenerative approaches show promise but remain investigational until standardized protocols and large-scale trials are established.

Essay
Public Health and Healthcare
Health Policy and Services

Ziad D. Bsghdadi

Abstract: Purpose: To provide an evidence calibrated, time bound clinical framework for the use of 38% silver diamine fluoride (SDF) as interim stabilization for severe early childhood caries (SECC) in young children, addressing gaps in existing guidelines regarding treatment duration, exit criteria, equity, and system accountability. Methods: This framework was developed from the American Academy of Pediatric Dentistry (AAPD) guidance (2017–2025), the 2024 Cochrane review, real world utilization studies, and a narrative review proposing a preservation to precision heuristic. Recommendations are expressed using GRADE terminology. Results: The framework includes ten recommendations, a systems drift principle, explicit time thresholds (< 6 months, 6–12 months, >12 months), a 12 month reassessment mandate, equity guardrails, a bridge vs destination consent model, and a future research agenda. A clinical vignette contrasts appropriate short term bridging with prolonged temporization due to access barriers. Conclusion: SDF is conditionally recommended for caries arrest in primary teeth. In children with SECC, SDF should be used within a documented, time bound preservation to precision pathway. SDF should not become an open ended substitute for definitive restorative care. Equity explicit implementation prevents the framework from penalizing underserved children.

Review
Biology and Life Sciences
Agricultural Science and Agronomy

Sonia Ojeda

,

Catarina Leal

,

Emilia Diaz-Losada

,

David Gramaje

Abstract: Grapevine trunk diseases (GTDs), caused mainly by fungal ascomycetes and some basidiomycetes, threaten vineyard sustainability through yield losses, higher management costs and reduced vineyard lifespan. Because pruning wounds are the main infection courts, pruning decisions strongly shape GTD risk. This review critically analyses advances over the last decade, with a particular focus on studies published since 2018, on how pruning practices influence infection dynamics and management outcomes across GTD complexes. We synthesize evidence on spore dispersal and weather drivers, temporal patterns of wound susceptibility, and the performance of mitigation strategies, including pruning timing (early/late and double pruning), training systems and sap-flow-oriented pruning concepts, optimization of wound number and size, and inoculum reduction through sanitation and remedial surgery. We also review recent field evaluations of pruning-wound protectants under artificial inoculation and natural infection, covering fungicides, biological control agents and physical barriers. Reported outcomes are highly variable among regions, climates and pathogen groups, indicating that universal recommendations are unreliable without local epidemiological context. Priority research gaps include: (i) field validation of traditional pruning concepts (protective wood/desiccation cones and diaphragm preservation) under natural infection; (ii) the epidemiological contribution of growing-season wounds; (iii) mechanistic drivers of the wide range of reported wound-susceptibility duration; (iv) development of cold-tolerant biological control agents effective across pathogen-host combinations; and (v) validation and transferability of spore-dispersal and risk-forecast models across viticultural regions. Overall, GTD management is best approached as a region-adapted, integrated strategy combining pruning decisions, inoculum management and timely wound protection.

Article
Engineering
Telecommunications

Massimo Celidonio

,

Fernando Consalvi

Abstract: The integration of satellite and terrestrial networks within the same spectrum is a key enabler for extending mobile connectivity in future communication systems. In this context, the Direct Connectivity between Mobile Satellite Service and International Mobile Telecommunications user equipment (DC-MSS-IMT) paradigm, currently under study within the International Telecommunication Union [1], foresees the use of terrestrial IMT frequency bands by satellite systems to directly serve conventional mobile devices. This paper presents an experimental study to assess the coexistence between a terrestrial 5G-NR receiver and a co-channel interfering signal representative of a Low Earth Orbit (LEO) satellite downlink. A controlled laboratory setup in conducted configuration was implemented to ensure repeatability and accurate control of interference conditions. Measurements were performed over four carrier frequencies representative of IMT bands (763 MHz, 1482 MHz, 2150 MHz, and 2635 MHz) [2], considering different traffic load conditions (100% and 50%) and Doppler shifts associated with satellite motion. The interference impact was evaluated in terms of receiver desensitization, defined as the increase in the total received power relative to the baseline noise level [3]. The results show that a 1 dB desensitization threshold is consistently reached when the interfering signal power is approximately 5–6 dB below the receiver noise floor, corresponding to an interference-to-noise ratio (I/N) of about −6 dB. This behavior is observed across all tested frequency bands, traffic conditions, and Doppler scenarios, indicating limited sensitivity to frequency offsets within the considered range. The findings confirm the validity of commonly adopted coexistence criteria and provide experimentally derived reference values to support ongoing regulatory and technical studies on spectrum sharing between satellite and terrestrial IMT systems.

Article
Chemistry and Materials Science
Analytical Chemistry

Sami El Deeb

,

Mohammed Al Broumi

,

Reem K. Almarsafy

,

Maria Kristina Parr

Abstract: A cornerstone in transferring a classical liquid chromatography (LC) ultraviolet/visible (UV/Vis) method into greener and sustainable analytical method should consider the safety and toxicology of the used organic solvent in the method. Organic solvent portions used in the mobile phase may be replaced by a green solvent that is ideally bio-based and biodegradable to increase the greenness of the method. However, the implementation of a new solvent for high performance liquid chromatography (HPLC-UV/Vis) requires consideration of its environmental and health impact, cost-effectiveness, user-friendliness, and impact on the analytical performance and suitability of its chromatographic method. Existing greenness, blueness, and redness metrics expressing whiteness for evaluating the comprehensive sustainability of methods after solvent replacement overlook the chromatographic suitability of the selected solvent, this may potentially lead to suboptimal solvent replacement and an incomplete view of its capabilities. In this work, the authors present a Universal Suitability and Sustainability Index (USSI), a sixteen-parameter scoring system that quantifies four main factors for complete evaluation of a new solvent for implementation in HPLC. This index is beyond the white analytical chemistry principle. The four main factors are chromatographic suitability, greenness, blueness, and redness. Three of these factors, are based on available tools and metrics to evaluate the environmental and practicability impact on the health, and the analytical performance of the method. The fourth factor is added as an important criterion to judge the suitability of the solvent for HPLC analysis and to give an overview about its analytical applicability. The new index has been used to evaluate traditional liquid chromatographic as well as green solvents-based methods to give a universal overview that aids users to drive a rapid impression on the weakness and strength aspects and makes it easier to judge the selection of the solvent and the evaluation of the overall method sustainability.

Article
Physical Sciences
Thermodynamics

Jordan Barton

Abstract: This paper assumes that a thermodynamic system can be composed purely of coherence and information, and constructs a working model on that basis. We derive operational parameters for such systems using definitions of the Certainty Equation, semantic entropy, semantic temperature, and formulate five laws and three modes of coherence and information systems. This analysis is then compared to the features of black holes.

Article
Engineering
Mechanical Engineering

Ali Abughalia

,

Carsten Stechert

Abstract: This paper investigates how software configuration, hardware type, user background and context of use influence the usability of Virtual Reality (VR) systems in engineering product development. A VR usability assessment approach that combines task-based questionnaires, the System Usability Scale (SUS) and the NASA-TLX questionnaire was evaluated systematically across six experiments involving students, junior engineers and senior engineers in academic and industrial settings. The results demonstrate that user background and task context are at least as signifi-cant as the underlying hardware or software in influencing perceived usability and acceptance. Standalone headsets achieve higher usability scores with inexperienced users, whereas PC-based systems are still necessary for high-precision engineering tasks. Professional engineers primarily evaluate VR in terms of workflow integration, precision and return on investment, whereas students focus more on novelty and the interaction experience. Based on these findings, practical design recommendations have been derived for se-lecting a VR system, adapting interaction concepts, and implementing VR in product development processes. The study highlights that VR should not be deployed as a one-size-fits-all solution, but rather as a tool that is both context-specific and us-er-centered. It also demonstrates how systematic, iterative usability evaluation can directly support the successful industrial integration of VR technologies.

Review
Biology and Life Sciences
Animal Science, Veterinary Science and Zoology

Kathryn Ruth Connolly

,

Shane Maher

,

Torres Sweeney

,

John V. O'Doherty

Abstract: In commercial pig production systems, early weaning disrupts the coordinated maturation of the gastrointestinal tract, resulting in reduced feed intake, impaired digestive capacity, altered microbial ecology and increased susceptibility to post-weaning diarrhoea (PWD). Although enterotoxigenic Escherichia coli (ETEC) is frequently implicated, variation in disease expression is not explained by pathogen presence alone, but reflects interactions among host physiology, nutrient flow and microbial metabolism. This review examines the regulation of the gut microbiota in post-weaned pigs through the interaction between digestive capacity and dietary substrate supply. It proposes substrate flow as the organising principle linking digestive function, diet composition and microbial metabolism. Gut microbial function is regulated primarily by substrate availability, which is determined by the alignment between diet composition and host digestive capacity. When this alignment is disrupted, undigested nutrients are redistributed to the hindgut, driving a shift from saccharolytic to proteolytic fermentation. This transition generates metabolites that impair epithelial integrity, increase luminal pH and favour proliferation of opportunistic bacteria, thereby promoting intestinal dysfunction. Within this context, nutritional strategies, including optimisation of dietary protein, provision of fermentable carbohydrates and support of gastric function, act by regulating substrate flow rather than directly modifying microbial composition. Organic acids, functional ingredients and maternal influences operate through the same mechanisms, shaping nutrient digestion, microbial exposure and metabolic outcomes. The characteristic post-weaning increase in Enterobacteriaceae and reduction in microbial diversity are therefore best understood as consequences of altered substrate flow and luminal conditions, rather than primary initiating events. This interpretation provides a mechanistic basis for the design of integrated nutritional and management strategies to improve gut health and reduce antimicrobial reliance in pig production systems.

Review
Medicine and Pharmacology
Oncology and Oncogenics

Alberto Zaniboni

Abstract: Liposomal irinotecan (nal-IRI) has emerged as a cornerstone in the treatment of metastatic pancreatic ductal adenocarcinoma (mPDAC), particularly in combination with 5-fluorouracil and leucovorin (5-FU/LV) following progression on gemcitabine-based therapy. Despite its demonstrated survival benefit, gastrointestinal toxicity—most notably diarrhea—remains a clinically significant adverse event that can compromise dose intensity, treatment adherence, and patient quality of life. Diarrhea associated with irinotecan-containing regimens is mechanistically complex, encompassing both acute cholinergic and delayed secretory components mediated by mucosal injury and enterohepatic recirculation of the active metabolite SN-38. The liposomal formulation alters the pharmacokinetic profile of the drug, prolonging systemic exposure while maintaining toxicity risks. This review provides a comprehensive and updated overview of the pathophysiology, incidence, and clinical implications of diarrhea in nal-IRI–based regimens. Evidence-based management strategies are discussed, including pharmacologic interventions, supportive care, dose modifications, and patient education. Emerging therapeutic approaches—including microbiome modulation and pharmacogenomic-guided therapy—are also explored. A multidisciplinary and proactive management approach is essential to optimize outcomes and minimize toxicity.

Review
Computer Science and Mathematics
Artificial Intelligence and Machine Learning

Vinuka Silva

,

Nipuna Senanayake

Abstract: Search algorithms have long underpinned game-playing artificial intelligence, however as game domains expanded from small deterministic board games to large scale, partially observable, real-time environments, no survey has systematically organized this evolving literature into a unified taxonomy or evaluated algorithms through a consistent design space. This taxonomy based survey addresses that gap through domain-scoped literature clustering, analyzing 61 works from 1946 to 2025 across six thematic clusters: spatial pathfinding and navigation, adversarial game tree search, Monte Carlo tree search and bandit based planning, metaheuristic optimization, learning augmented search, and search under uncertainty and partial observability. A four dimensional design space — covering interaction topology, information structure, computational regime, and source of search guidance enables consistent cross-cluster comparison of hybrid approaches. Analysis reveals a paradigm shift from analytic correctness and proof driven evaluation toward empirical benchmarking, sampling based planning, and neural guided search. Cross-cluster synthesis identifies fundamental tensions among decision quality, formal guarantees, and resilience under uncertainty, and documents an evolution in evaluation methodology from deterministic metrics to distributional robustness testing. Open challenges are identified, pointing toward principled frameworks for managing trade offs among quality, optimality, and robustness. This survey provides artificial intelligence researchers and game developers with a structured reference for selecting and evaluating gaming search algorithms across diverse environments.

Article
Chemistry and Materials Science
Physical Chemistry

Xiangxi Zhang

,

Qing Zhou

Abstract: In this study, hydantoin (C₃H₄N₂O₂) was selected to investigate the photoluminescence mechanism of non-typical luminescent compounds. The emission spectra of single crystals were examined using a laser confocal microscope. Within the same crystal, the peak shape and position were consistent across different regions, while the intensity varied; this phenomenon is attributed to confinement-induced emission. For different crystal blocks, variations in molecular packing modes led to changes in both peak shape and position. Combined with theoretical calculations and analyses, the results show that: as the molecular number increases, the energy gap decreases and the excitation wavelength increases (lower excitation energy); the hole-electron attraction energy, delocalization index, and overlap degree all decrease, with the hole delocalization index decreasing faster than that of the electron; the spin-orbit coupling coefficients for high-lying triplet states are more sensitive to the molecular count; and the intersystem crossing rate increases sharply with increasing energy level. In summary, the number and mode of molecular packing in the crystal influence the excited-state electronic structure and hole-electron interactions, thereby determining the luminescence behavior of non-typical luminescent compounds.

Article
Physical Sciences
Condensed Matter Physics

N. Zen

Abstract: By making periodic thru-holes in a suspended film, the phonon system can be modified. Motivated by the BCS theory, the technique -- so-called phonon engineering -- was applied to a metallic niobium sheet. It was found that its electrical resistance dropped to zero at 175 K, and the zero-resistance state persisted up to 290 K in the subsequent warming process. Despite the initial motivation, neither these high transition temperatures nor the phase transition with thermal hysteresis can be accounted for by the BCS theory. Therefore, we abandon the BCS theory. Instead, it turns out that the metallic holey sheet is partly oxidized to form a niobium-oxygen square lattice, which has points of resemblance to a copper-oxygen plane, the fundamental component of cuprate high-Tc superconductors. Therefore, the pairing mechanism underlying this study should be related to that of cuprate high-Tc superconductors, which we may not yet understand. In addition to the electrical results of zero resistance, the holey sheet exhibited a decrease in magnetization upon cooling, i.e., the Meissner effect. Moreover, the remnant magnetization was clearly detected at 300 K, which can only be attributed to persistent currents flowing in a superconducting sample. Thus, this study meets the established criteria for a conclusive demonstration of true superconductivity. Finally, the superconducting transition with the unambiguous thermal hysteresis is discussed. According to Halperin, Lubensky, and Ma, or HLM for short, any superconducting transition must always be first order with thermal hysteresis because of the intrinsic fluctuating magnetic field. The HLM theory is very compatible with the highly oriented system harboring two-dimensional superconductivity.

Article
Physical Sciences
Astronomy and Astrophysics

John Henderson

Abstract: A number of approaches to a theory of quantum gravity assume the cosmological fabric of spacetime is distinct from the spacetime of the material world of matter and energy. On a short time scale, one cannot distinguish between the fabric of spacetime expanding, nominally due to dark energy, or the scale of the material world contracting with respect to the fabric of spacetime. Contraction of the scale of the material world (length, time, mass, and charge contracting equally) maintains observable physical laws and results in a decreasing derived dark energy density matching that reported by the DESI Collaboration in March 2025. The DESI Collaboration fits to the dark energy density over time show a distinct difference between those using scale-dependent supernovae data and those using mostly scale-independent angular measurements, such as from CMB and BAO measurements. That difference is resolved by applying a scale contraction rate of ~3%/Gyr to the supernovae data. Scale contraction of the material world eliminates the need for dark energy to explain the apparent expansion of space, resolving the ~10122 discrepancy between the dark energy density required to match observation and that calculated for the vacuum energy as the mechanism for dark energy. The large force of the vacuum energy is a potential mechanism for compression of the material world, and would explain why the observed expansion only occurs outside of gravitationally bound systems. A scale-contraction model for cosmological kinematics explains why the dark energy density appears to be decreasing without requiring the underlying vacuum energy to be changing with time. Scale contraction of the material world predicts the observed directions and order of magnitude of the Hubble tension and the S8 tension, which has been a challenge to other proposed modifications of Lambda-CDM since those two tensions have opposite trends over time, the Hubble constant being about 10% larger in the late universe compared to the early universe, and the structure constant, S8, about 10% smaller. Scale contraction of the material world can be tested by modifying the Lambda-CDM cosmological model to include scale contraction over time, and assessing if the Hubble, S8, and other tensions are quantitatively reduced or resolved.

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