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Article
Biology and Life Sciences
Agricultural Science and Agronomy

Victor Hugo Almeida Lima

,

Elton Fialho dos Reis

,

Josué Gomes Delmond

,

Eduardo Henrique da Silva Santana

,

Ivano Alessandro Devilla

Abstract: Most studies in the field of application technology have focused on the interaction between adjuvants and agrochemicals, highlighting the need for further research to evaluate the behavior of adjuvants in association with other classes of crop protection products. In this context, the objective of this study was to evaluate the influence of adjuvants and air velocity on spray drift deposition in simulated applications conducted in a wind tunnel using a bioinsecticide based on Bacillus thuringiensis. The experiment was carried out in an open-circuit, blower-type wind tunnel installed at the Agricultural Machinery Laboratory of the State University of Goiás – Central Campus. The study was conducted in a completely randomized design arranged in a 5 × 4 × 4 factorial scheme, with three replications. Treatments consisted of five horizontal distances from the spraying point (0.45, 0.75, 1.05, 1.35, and 1.65 m), four wind speeds inside the tunnel (1, 2, 3, and 4 m s⁻¹), and four spray solution formulations (water + dye; bioinsecticide + dye; bioinsecticide + vegetable oil + dye; and bioinsecticide + surfactant + dye). For deposition sampling, artificial targets were positioned transversely to the airflow and, immediately after spraying, were divided into lower, middle, and upper thirds relative to the height of the test section. Data were obtained by spectrophotometry and, after verifying the ANOVA assumptions, subjected to ANOVA (P < 0.05). When significant, mean comparisons and regression analyses were performed. Statistical analyses were conducted using the R and Sisvar software packages. Mean deposition values were converted into drift percentage as a function of the total sprayed volume. The experimental data were also subjected to geostatistical analysis using GS+ software (Version 7®). After confirming spatial dependence, contour maps were generated using kriging. Higher wind speeds led to higher drift percentages. The use of the adjuvant Break Thru® contributed to reducing drift in the upper and middle thirds. In the lower third, at a wind speed of 1 m s⁻¹, the addition of Break Thru® reduced drift; however, at 4 m s⁻¹, adjuvants did not reduce deposition compared to the spray solution prepared with the biological insecticide. The analyzed variable showed a strong spatial dependence across all treatments.

Review
Biology and Life Sciences
Biology and Biotechnology

Simona Viglio

,

Maria Antonietta Grignano

,

Marilena Gregorini

,

Teresa Rampino

,

Giampiero Pietrocola

,

Paolo Iadarola

Abstract: Human neutrophil elastase (HNE) is a central mediator of neutrophil-driven inflammation. Yet, despite decades of research and drug development, therapies targeting HNE have not consistently translated into clear clinical benefits. We suggest that this translational gap partly arises from how HNE has traditionally been conceptualized, as a single enzyme to inhibit. In biological systems, however, HNE operates within a complex and tightly regulated network of proteases and inflammatory mediators. This network is spatially compartmentalized and strongly in-fluenced by local redox conditions, making HNE activity highly context dependent. From a systems perspective, HNE acts as an amplifier of inflammation. Its extracellular activity connects several pathological processes, including activation of innate immunity, extracellular matrix degradation, disruption of epithelial and endothelial barriers, and the transition toward chronic inflammation. In this review, we integrate insights from enzymology, systems biology, and clinical research to reassess the development of HNE inhibitors, ranging from endogenous anti-proteases to more recent reversible synthetic compounds. Despite their chemical and pharma-cological diversity, many of these strategies have encountered similar limitations. We therefore argue that future therapeutic approaches should move beyond the inhibition of HNE as an iso-lated target and instead aim to modulate the broader protease network, with particular attention to drug–target kinetics and precise delivery to disease-relevant microenvironments.

Review
Biology and Life Sciences
Life Sciences

Usha Devi

,

Jörn-Hendrik Weitkamp

,

Jeffrey S. Shenberger

,

Parvesh Mohan Garg

Abstract: Necrotizing enterocolitis (NEC) remains one of the most devastating gastrointestinal emergencies in neonates and also presents major diagnostic challenges. Despite extensive research, NEC still lacks a practical definition and relies on a set of nonspecific clinical, laboratory, and radiological findings rather than a single pathognomonic presentation or test. The modified Bell staging system remains the most widely used framework in clinical practice and research, but it was originally developed to base the treatment decisions rather than helping in diagnosis and has important limitations when applied as a diagnostic aid. Clinical and radiological criteria used for early stages of NEC are nonspecific, progression of the disease is not always linear, radiographic signs are inconsistently present, and histopathological confirmation is unavailable in most of the cases as surgery is not undertaken in all the cases. These limitations have led to the opinion that even the modified Bell staging is “broken” when it is used to define the disease itself. At the same time, increased understanding about gut immunity and microbiome progression, and neonatal hemodynamics have made it increasingly clear that NEC is not a single uniform disease. It is now regarded as a heterogeneous syndrome comprising multiple phenotypes that share a final common pathway of intestinal injury and necrosis but differ in timing, predisposing factors, mechanisms involved, and clinical course. These presentations overlap with several neonatal conditions including spontaneous intestinal perforation, septic ileus, cow’s milk protein allergy, congenital heart disease-related intestinal hypoperfusion, viral enterocolitis, malrotation with volvulus, and intussusception. This review discusses controversies in the definition and staging of NEC, consolidates alternative diagnostic criteria proposed beyond Bell’s system, and elaborates a phenotype-based framework for clinical distinction. Also, the review throws light on the clinical mimickers, practical bedside diagnosis using serial clinical assessment and imaging, consequences of NEC, and emerging precision medicine approaches. A shift from stage-based labeling toward a practical, phenotype-informed framework may improve diagnostic precision, reduce misclassification, and enhance both clinical care and research.

Article
Computer Science and Mathematics
Computational Mathematics

Ibar Federico Anderson

Abstract: The classical Goldbach conjecture asks whether every even integer n >= 4 can be written as n = q + r with q, r prime. This paper studies a structurally distinct variant: for a prime p >= 2, let N(p) = #{ (q, r) subset of primes: q <= r, q + r = p + 1 } count the Goldbach representations of p + 1 when p itself is prime. The additional triple‑primality constraint – p, q, r all simultaneously prime – produces an arithmetic profile governed by a new constant S_∞ != 2 C_2. Proved (unconditional). The Euler product: S_∞ = ∏_{ℓ > 2, ℓ prime} ( 1 + 1/((ℓ-1)(ℓ-2)) ) = 1.74272535...converges absolutely and equals the limiting Cesàro mean of S(p+1) over shifted primes (Theorem 3.5). Two congruence theorems for Mirror and Anchor‑3 primes are proved (Theorems 4.3 and 4.6). The equivalence α_∞ = 1 / S_∞ ⇔ Ĉ(x) → 2 C_2 is established unconditionally (Proposition 5.4). Three analytic gaps in the Goldbach‑Riemann bridge for Ψ*(x) are closed unconditionally (Theorems 6.5, 6.6, 6.9), yielding the explicit formula (Theorem 6.10). Conditional (GRH, GRH+HL‑B): Under the Generalised Riemann Hypothesis the convergence rate |S̄(x) – S_∞| = O( S_∞ log x / √x ) is established (Theorem 3.6). Under GRH and Hardy‑Littlewood Conjecture B, N(p) >= 1 for every prime p > 11 is proved completely (Theorem 10.1). The parity obstruction is identified as the precise barrier to proving N(p) >= 2 by current sieve methods (Proposition 10.3).Computationally verified: N(p) >= 2 for every prime 11 < p < 6.79×10^7 (4,000,000 primes, zero violations, exhaustive Sieve of Eratosthenes). Probabilistically extended to 1000 randomly sampled 127‑bit primes p ~ 10^38 via Miller‑Rabin (k = 10 rounds), and independently to 100 samples at 512 bits (p ~ 10^154). Discrete Mellin transform experiments detect 72 of the first 100 non‑trivial Riemann zeros in the residuals ε(p) = (N(p) – N̂₃(p)) / N̂₃(p) at significance level p < 0.01 (range p in [10^6, 2×10^6], n = 70,435 primes, 200 permutations), improving the previous 21/50 result by a factor of 3.4. Class‑fraction experiments at RSA‑1024 (p ~ 10^309) and RSA‑2048 (p ~ 10^617) confirm Orphan fractions of 98% and 100% respectively, consistent with predicted density‑zero behaviour of Mirror and Anchor‑3 primes. Epistemic status: All claims carry explicit labels: [PROVED], [COND. PROVED], [COMP. VERIF.], [CONJECTURE], [NEW], [CORRECTED]. No claim is presented without its status. The central conjectures are open.

Article
Social Sciences
Education

Sixbert Sangwa

,

Claver Ndahayo

,

Fabrice Dusengumuremyi

,

Placide Mutabazi

Abstract: Background: Online and blended provision has expanded rapidly in higher education, yet much of the literature still treats digital transition as a pedagogical or technological adjustment rather than an institutional transformation problem. Problem: Conventional universities, especially in African higher education, often face pressure to move online under conditions of constrained infrastructure, uneven digital access, evolving regulation, and heightened concern about academic standards. Existing scholarship is rich on course design, faculty attitudes, and learner satisfaction, but comparatively weak on the full institutional architecture required for credible transition. Objective: This article develops a university-wide framework for bringing conventional institutions online in ways that are regulatorily legitimate, academically credible, operationally resilient, socially inclusive, and financially sustainable. Research question: What institutional architecture is required to move a university from conventional face-to-face delivery to credible, quality-assured online or blended provision in African higher education? Design: A systematized integrative review combined with comparative policy analysis was conducted across peer-reviewed higher education literature and authoritative framework and regulatory documents. The synthesis drew together institutional adoption studies, quality assurance guidance, digital transformation frameworks, and policy texts, with Rwanda used as a policy-reference environment rather than a single-country case. Findings: Credible digital transition depends on the alignment of five layers: contextual boundary conditions, a steering layer of governance and policy, seven operational domains, phased implementation sequencing, and outcome-focused feedback loops. The review shows that digital provision fails when institutions treat the learning management system as the reform, underinvest in staff and student support, delay policy redesign, or reduce assessment integrity to surveillance alone. It succeeds when governance, curriculum, quality assurance, infrastructure, data governance, and financing are intentionally coupled. Principal contribution: The article contributes an original Institutional Architecture for Credible Digital Transition framework and a companion University Online Readiness and Transition Toolkit comprising a readiness rubric, phased roadmap, and policy checklist. Implications: The framework offers an actionable basis for institutional leaders, regulators, and scholars seeking to design, evaluate, and sequence digital transition in African higher education without reproducing techno-solutionist assumptions.

Article
Engineering
Aerospace Engineering

Ibrahim Ibrahim Birma

,

Fangyi Wan

Abstract: Composite wing structures are widely used in unmanned aerial vehicles (UAVs) because of their high specific strength and stiffness, but they are vulnerable to localized impact events such as tool drops, runway debris and small bird or drone strikes. In many aerospace applications, carbon fiber–reinforced polymers (CFRP) are preferred for their high stiffness and weight efficiency, although they tend to fail in a brittle manner and are expensive. E-glass fiber composites, on the other hand, are tougher and cheaper, but usually considered less competitive in stiffness and impact resistance. This study numerically investigates the impact resistance of optimized E-glass fiber composite UAV wing skins compared with aerospace-grade carbon fiber skins, both supported by balsa-wood cores. A 3D finite element (FE) model of a 600 mm semi-span UAV wing segment was developed in Abaqus/Explicit, with a user-defined VUMAT implementing an orthotropic elastic law and a Hashin-type progressive damage model. A rigid spherical impactor (radius 8 mm) with various mass velocity combinations (0.5 kg at 5000 and 10 000 mm/s, and 1.0 kg at 20 000 mm/s) was used to represent low, medium and high energy impacts. E-glass material sets were defined and gradually improved, within realistic mechanical limits derived from published E-glass/epoxy systems, until a “maximum experimental limit” E-glass configuration was obtained. This optimized E-glass wing skin was then compared with carbon-fiber configurations taken as benchmark aerospace. The comparison is based on peak contact force, penetration or non-penetration, absorbed energy, and damage extent in the skin and sub-structure. The study also proposes a coupon- and sub-component-level experimental programme to validate the numerical predictions using drop-weight impact tests on E-glass and carbon-fiber laminates and on a scaled UAV wing segment. These findings indicate that suitably engineered E-glass composites can be a viable, cost-effective alternative to carbon fiber for impact-resistant UAV wing structures.

Article
Computer Science and Mathematics
Artificial Intelligence and Machine Learning

Md Shakib Hasan

,

Mst Mosaddeka Naher Jabe

,

Teguh Daniel Bandaso

,

Aiman Iftikhar

,

Sunita Rathore

,

Most Somaya Akther

Abstract: Introduction: Educational systems have historically adapted to incorporate technological innovations, but the success of these processes may vary greatly. Some tools become embedded in established processes, while others lead to radical transformation. In this paper, we examine the development of educational technology and recommend and critique certain technologies that facilitate existing industrial education approaches and others that require the restructuring of how educational aims and methods are defined and implemented. Purpose: This study aims to evaluate this optimization-restructuring schism in a systematic manner. We seek to show, through a century of technological transformation, that 20th-century technologies were primarily appropriated to sustain standardization and efficiency, while 21st century artificial intelligence (AI) is an unassimilable phenomenon in need of epistemological and pedagogical reworking. Method: The methodology of this research uses a Comparative Historical Analysis (CHA) approach of four critical educational technologies: the ballpoint pen, the personal computer, the internet, and artificial intelligence. This analysis is guided by a new six-dimensional architecture assessing impacts on: (1) Access & Equity, (2) Pedagogical Transformation, (3) Epistemological Foundations, (4) Student Agency & Role, (5) Teacher Role & Identity, and (6) Institutional & Systemic Effects. Each dimension was systematically coded for optimization versus restructuring impacts based on historical evidence. Results: In our analysis, we determine a distinct historical stalemate of the gravity of optimization, whereby the transformational potential of the pen, PC, and (to a smaller degree) internet, was expropriated to scale up and institutionalize the industrialized education model. Nonetheless, AI has inherent duality: it may be used as a tool of optimization (automated grading, content generation) or used as an agent of restructuring (co-creation, critical inquiry). Its capacity to generate an epistemic disruption is that it questions the authority of authorship and knowledge, renders standardized assessment somewhat redundant, and reinvents learning as a process of critical analysis and human-AI co-creation. The outcome depends on deliberate institutional choices. Conclusion: The findings suggest that the introduction of AI will have to leave the historical trends of technological assimilation behind. This will require radical policy and pedagogical shifts, such as new paradigms of assessment whose focus is on human skills, the implementation of powerful ethical AI governance systems, and the re-imagining of teacher roles as ethical mentors and facilitators of learning. The future of education relies on steering this restructuring, which is inevitable, with a commitment to equity and human-centric values.

Article
Engineering
Civil Engineering

Anastasios I. Stamou

,

Georgios Mitsopoulos

,

Athanasios Sfetsos

,

Athanasia Tatiana Stamou

,

Aristeidis Bloutsos

,

Konstantinos V. Varotsos

,

Christos Giannakopoulos

,

Aristeidis Koutroulis

Abstract: Climate change poses significant challenges to the operation and safety of dam and reservoir (D&amp;R) systems, particularly in regions characterized by water scarcity and high climate variability. This study presents a structured methodology for climate risk assessment that integrates regional climate projections, system-specific thresholds, and a semi-quantitative risk matrix approach. A key innovation is the explicit linkage between climate indicators and system performance through physically based thresholds, combined with empirically derived exceedance probabilities from high-resolution climate projections. The methodology is applied to the Almopeos D&amp;R system in Northern Greece using an ensemble of statistically downscaled CMIP6 simulations under two emission scenarios (SSP2-4.5 and SSP5-8.5) and two future periods (2041–2060 and 2081–2100). Three climate indicators are analyzed: TX35 (temperature extremes), CDD (consecutive dry days), and Rx1day (extreme precipitation). Results indicate that temperature increase is the dominant climate risk hazard, leading to increased irrigation demand and reduced system reliability, with risks classified as high to very high. Drought conditions represent a secondary but important risk, becoming critical during prolonged dry periods affecting reservoir storage, while extreme precipitation events exhibit low likelihood but potentially high consequences for dam safety. Adaptation measures are prioritized using a qualitative multi-criteria approach, highlighting the effectiveness of operational measures, while structural and monitoring interventions remain essential for ensuring system safety. The proposed methodology provides a transparent and transferable framework for climate-resilient planning of water infrastructure systems.

Article
Engineering
Civil Engineering

Yalei Song

,

Yan Liu

Abstract: Laminated Veneer Lumber (LVL) is engineered product produced by adhesively bonding fast growing Poplar veneers. Comparing dimensional lumber, LVL provides better use rate and fulfills structural wood requirement for wood structure building. And have proven this thing about the lateral mechanical properties for LVL shear walls, also have done investigations into what the hold downs and the loads of those that get put into it do to them when trying out these types of things in an effort to study their lateral mechanical workings. Comparisons with different types of wooden shear wall structures were carried out for this reason. According to the research data obtained through experiments and analyses, suggestions were proposed to designers regarding how they might go about designing hold-down devices in cases wherein these were employed with respect to particular kinds of shear walls which themselves had their own particular features and attributes.

Article
Physical Sciences
Radiation and Radiography

Songchao Wang

,

Hanwen Zhang

,

Gangyi Chen

,

Yuzhu Pan

,

Yulian Zhang

,

Qianqian Huang

,

Jinbao Chen

,

Xin Wang

Abstract: CH3NH3PbBr3 (MAPbBr3) single crystals have shown great potential in X/γ-ray detection. However, stable electrodes for MAPbBr3 single crystals still remains challenging. In this work, multi-layer electrodes including Au, Au/Ti and Au/Pt/Ti are investigated. Through I-V characterization, Au/Pt/Ti shows Ohmic contact behavior and lowest dark current. The potential contact is also confirmed by Kelvin force probe. Based on this low noise electrodes, 59.5 keV monochromatic X-ray photon counting detection and imaging is demonstrated. This work provides useful information for electrodes design in lead halide perovskites-based optoelectronic devices.

Article
Engineering
Mechanical Engineering

Valentin Kamburov

,

Rayna Dimitrova

Abstract: The article discusses the methods for classifying processes for testing and processing metals by plastic deformation, based on the characteristics of their stress-strain state. The basic methods for determining the stress and strain states using fundamental scalar quantities representing the stress and strain tensors are discussed. Equations have been derived for the quantitative determination of the type of stress-strain state through a combination of principal stresses, represented as the strain rigidity of the deformation mode. A classification of deformation processes for testing and processing metals by plastic deformation is proposed, using the stress triaxiality parameter and the strain rigidity coefficient. Some 2D and 3D diagrams have been created based on simulation modeling of plastic deformation processes using virtual tools, allowing the grouping of processes according to the measured principal stresses and their combinations, which represent the stress triaxiality and strain rigidity of the deformation mode. By determining the type of grouping in these diagrams and the change in the stress-strain state with increasing strain levels, the characteristic features of the deformation processes used in materials testing and in the processing metals by plastic deformation of metals/alloys have been confirmed.

Article
Biology and Life Sciences
Ecology, Evolution, Behavior and Systematics

Joaquín L. Reyes-López

Abstract: The delimitation of cryptic species represents one of the main challenges, particularly in groups with low external morphological differentiation. In this context, scanning electron microscopy (SEM) enables the detection of diagnostic characters at the microscale. This study evaluates the potential of ocular morphology for interspecific discrimination within a group of species of the genus Temnothorax. A total of 246 workers from 52 nests, 13 populations, and 8 species from the Iberian Peninsula and North Africa were analyzed. Morphometric variables related to compound eyes were quantified from SEM images (ommatidia number, interommatidial setae, eye diameter). Data were analyzed using ANOVA, effect size estimation (η²), Linear Discriminant Analysis (LDA), and Random Forest models. All variables showed significant differences among species (p < 0.001), with varying discriminative power. Variables related to ommatidial organization exhibited the highest classification performance, achieving high rates of correct species assignment in multivariate analyses. The use of nest-level means values substantially improved classification accuracy. These results demonstrate that ocular morphology analyzed through SEM represents a promising complementary tool for species discrimination in Temnothorax, complementing traditional and molecular approaches.

Article
Engineering
Civil Engineering

Jeong-Hwan Bang

,

Bilguun Mend

,

Yong-Sik Chu

Abstract: This study develops a comparative screening framework for evaluating the feasibility of low-temperature clinker production using waste-derived raw meals under melt-phase and Fe-in-liquid constraints. The work addresses the need to connect two strategies for lower-emission cement manufacture that are often discussed separately: partial substitution of conventional raw materials with waste-derived inputs and reduction of clinker burning temperature through mineralized processing. A secondary-data analysis was conducted using selected open-access case studies and an open-access spreadsheet dataset, from which quantitative variables related to composition, process conditions, clinker formation, and cement performance were extracted and compared. The results show that feasibility depends not only on burning temperature, but also on major-oxide compatibility, minor-element constraints, burnability, clinker phase balance, melt-related indicators, and final cement performance. In the waste-substitution benchmark, MSWI bottom ash was compositionally feasible only within a limited substitution range controlled by Fe2O3 content. In the mineralizer benchmark, a reduction in burning temperature from 1450 ∘C to 1350 ∘C was found to be a practical benchmark for reduced-temperature clinker production, whereas further reduction to 1300 ∘C required stronger chemical assistance and led to performance penalties. Overall, the proposed framework distinguishes favorable, conditionally feasible, and constrained pathways and provides a basis for screening candidate systems before experimental validation.

Review
Biology and Life Sciences
Neuroscience and Neurology

Cyprien G J Guerrin

,

Serge H Ahmed

Abstract: Alcohol use disorder (AUD) is a major contributor to global disease burden and a leading cause of preventable death, yet available treatments remain modestly effective. Although rodent models are widely used to study alcohol-related behaviors and guide pharmacotherapy development, many treatments with strong preclinical efficacy fail clinically. Here, we propose a reward-component framework that separates ethanol intake into four components: pre-oral, oral, post-oral peripheral, and post-oral central drug rewards. Synthesizing behavioral, pharmacological, and neurobiological evidence, we find that the component primarily sustaining high ethanol intake in rodents remains unclear, with intake reflecting mixed oral and post-oral rewards. In contrast, human AUD is predominantly sustained by post-oral central drug reward, creating a translational misalignment in pharmacotherapy testing. Pharmacotherapies act across multiple components, and translational failure may arise from misalignment between the components sustaining drinking in rodent models and human AUD. This framework provides a basis for developing more predictive preclinical models and more effective pharmacological interventions.

Article
Medicine and Pharmacology
Orthopedics and Sports Medicine

Achille Saracco

,

Leo Massari

,

Marco Amadio

,

Gaetano Caruso

Abstract:

Background: Evidence on the role of synthetic biomimetic bone substitutes in the surgical management of proximal humerus fractures remains limited. This study aimed to evaluate the clinical, radiographic, and safety outcomes of a porous hydroxyapatite bone substitute used as an adjunct to locking-plate fixation in proximal humerus fractures with metaphyseal bone loss. Methods: We performed a retrospective cohort study including 45 patients treated between January 2022 and January 2025 with open reduction and internal fixation using a locking plate and a preformed porous hydroxyapatite scaffold (ENGIpore SH). Patients were evaluated clinically and radiographically at 1, 3, 6, and 12 months after surgery. Functional outcome was assessed with the Constant-Murley Score (CMS), and pain was assessed using the Visual Analogue Scale (VAS). Longitudinal changes over time were analyzed using mixed-effects models for repeated measures. Results: CMS improved progressively over follow-up, whereas VAS pain scores decreased significantly over time. No cases of device migration or radiographic resorption were observed during follow-up. Adverse events were recorded, but no complication was considered directly attributable to the implanted biomaterial. Conclusions: In this retrospective series, graft augmentation with a porous hydroxyapatite scaffold during locking-plate fixation of proximal humerus fractures with bone void was associated with progressive functional improvement and pain reduction, without evident device-related safety concerns. Owing to the observational design and lack of a control group, these findings should be interpreted as supportive of feasibility and short- to mid-term safety rather than proof of biomaterial efficacy.

Article
Chemistry and Materials Science
Nanotechnology

Weitao Li

,

Zeyun Dong

,

Zhengyu Zhang

,

Luoman Zhang

,

Qizhe Wang

,

Shang Li

,

Shuai Li

,

Lei Wang

,

Jialin Liu

Abstract: Industrial dye wastewater poses severe environmental and health risks, creating an urgent demand for efficient and sustainable remediation technologies. Herein, hierarchically porous hollow TiO2 nanofibers (HNFTi) were constructed through electrospinning and coupled with blue-, green-, and orange-emissive graphene quantum dots (b-, g-, and o-GQDs) to fabricate visible-light-responsive heterojunction photocatalysts. By tailoring the surface functional groups and heteroatom doping of GQDs, a progressive fluorescence redshift was achieved, which effectively narrowed the bandgap and extended visible-light absorption. Benefiting from the synergistic effects of the hierarchically porous hollow TiO2 architecture and the fluorescence-tuned GQDs, the resulting composites exhibited enhanced light harvesting, accelerated charge separation, and improved interfacial charge transfer. Among them, the 0.5 wt% o-GQDs/HNFTi composite showed the best photocatalytic performance, delivering a methylene blue degradation efficiency of 99.5% within 2 h under visible-light irradiation, markedly higher than that of pristine HNFTi (77.7%). Photoelectrochemical and Kelvin probe force microscopy analyses further confirmed the promoted carrier dynamics and effective interfacial separation of photogenerated electron-hole pairs. This work provides a feasible strategy for integrating structural engineering and fluorescence modulation to develop high-performance TiO2-based photocatalysts for wastewater treatment.

Article
Engineering
Metallurgy and Metallurgical Engineering

Petr Baron

,

Jozef Mikita

,

Vladimír Simkulet

Abstract: This study presents a comprehensive characterization of recycled aluminum briquettes produced by cold pressing of Al–Si–Mg alloy machining chips, along with an evaluation of their behavior during subsequent remelting. The objective was to assess the density, porosity, chemical composition, and metallurgical yield of the briquettes before and after melting, as well as to determine their suitability for use as deoxidizing additives in steelmaking. The cold-pressed briquette (Sample A) exhibited a low density of 2.29 g.cm-³ and a porosity of 12.1%, resulting from intergranular voids and residual lubricants. After melting and resolidification (Sample B), the density increased to 2.388 g.cm-3 and the porosity decreased to 8.15%. XRF chemical analysis confirmed a high degree of elemental homogeneity after melting with no indication of segregation, while SEM–EDS microstructural analysis verified the absence of significant intermetallic phases and revealed only a thin surface oxide layer. The metallurgical yield reached 94.2% with a low dross content (2.25%). The results demonstrate that, following appropriate preprocessing and optimized compaction, recycled aluminum briquettes constitute a stable and efficient secondary aluminum material suitable for steel deoxidation, and they can significantly reduce the environmental impact of metallurgical production.

Article
Computer Science and Mathematics
Artificial Intelligence and Machine Learning

Jaehwan Kim

Abstract: We propose the Knowledge Landscape hypothesis: a large language model’s forward pass encodes whether it knows the answer before producing any output token. Well-learned knowledge traverses deep convergence valleys in the activation landscape; unlearned queries traverse flat plains where signals disperse. These geometric properties manifest as two probe-free, single-pass signals—token-level entropy and layer-wise hidden-state variance— that precede and causally influence output uncertainty. Across two architecturally distinct models (Qwen2.5-7B and Mistral-7B) on TriviaQA, token entropy strongly discriminates known from unknown questions with large effect sizes, replicated at 300 samples per condition with a 95% bootstrap confidence interval entirely above 0.64. Hidden-state variance further localises a metacognitive locus in both architectures, consistently at 61–69% of total network depth, suggesting this is a universal structural property of transformer LLMs. Activation patching confirms causality: injecting a known- question hidden state into an unknown-question forward pass monotonically reduces output entropy. A lightweight abstention system built on these signals achieves a ROC-AUC of 0.804 and a 5.6 percentage-point accuracy gain over the unaided baseline, without any fine-tuning or additional training data.

Article
Biology and Life Sciences
Other

Sifan Ai

,

Yu Wang

,

Jiao Pan

,

Gang Hu

,

Ruiting Zhao

Abstract: Dajue Temple, a representative ancient architectural heritage in North China, houses numerous lacquered wooden components of exceptional historical and artistic value. Despite their significance, this study is the first to investigate the severe dark discoloration and black spotting afflicting these lacquer surfaces—damage triggered by prolonged environmental exposure that endangers structural integrity and long-term conservation. To address this unstudied threat, we confirmed the microbial origin of black spots using ATP bioluminescence assays, then characterized microbial communities via culture-dependent methods and ITS sequencing—identifying Cladosporium spp. as the dominant biodeterio-gen driving lacquer deterioration. Functional assays on carboxymethylcellulose (CMC) and guaiacol-amended potato dextrose agar (PDA) media verified the wood-degrading potential of isolated Cladosporium spp. Antifungal susceptibility screening against ten agents demonstrates that thymol and clove essential oils achieved significant efficacy at 200 mg/mL, while nano silver gel also provided durable suppression. We proposed targeted, relic‑friendly microbial control strategies tailored for ancient lacquered wooden components. These findings provided scientific guidance for the sustainable conservation and restoration of lacquered architectural elements in historic temples and comparable cultural heritage sites. In future work, environmental monitoring should be involved, which will help to clarify microbe–environment interactions and enable early warning of biodeterioration risks.

Article
Engineering
Metallurgy and Metallurgical Engineering

Marzanna Ksiazek

,

Lukasz Boron

,

Adam Tchorz

Abstract: High Velocity Oxy-Fuel (HVOF) thermal spraying is widely used for the deposition of dense coatings with low porosity, high hardness, and superior fracture resistance. Tungsten carbide–cobalt (WC–Co) coatings are extensively employed in industrial and aerospace applications due to their excellent wear resistance and mechanical performance; however, further improvement in crack resistance and adhesion remains a key challenge. In this study, WC–Co+Ni composite coatings were deposited on ductile cast iron by HVOF, with particular emphasis on the role of Ni particle addition in tailoring coating microstructure and performance. Microstructural characterization was carried out using light, scanning, and transmission electron microscopy (LM, SEM, TEM), while phase composition and chemical analysis were determined by X-ray diffraction (XRD) and energy-dispersive spectroscopy (EDS). The coatings exhibited a dense, low-porosity microstructure composed of partially molten Ni particles and fine WC and W₂C carbides embedded in a cobalt-based matrix, with locally nanocrystalline features. XRD analysis confirmed WC and W₂C as the dominant phases, with weak reflections indicating the possible formation of the η-phase (Co₆W₆C). Mechanical and tribological performance, evaluated by instrumented indentation and scratch testing, showed that Ni addition significantly enhances crack resistance, wear resistance, and coating–substrate adhesion. The results demonstrate that Ni-modified WC–Co coatings deposited by HVOF enable effective microstructural design, leading to improved durability and performance, which makes them promising candidates for advanced coating applications.

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