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Effects of cryogenic cooling on cutting temperature and surface roughness in turning of AA7075 aluminum alloy
Abstract The machining process is one of the most widely used methods for converting raw materials into finished products across various industries, owing to its numerous advantages, such as high precision, the capability to produce complex geometries, and superior surface finish. AA7075 aluminum alloy is extensively utilized in the aerospace and automotive sectors due to its exceptional strength-to-weight ratio, moderate corrosion resistance, and fair machinability. During machining operations, the simultaneous imposition of mechanical and thermal loads, coupled with severe plastic deformation, induces changes in the material’s mechanical and metallurgical properties—these alterations must be considered to enhance the component’s performance. Consequently, the surface integrity of the machined part, encompassing metallurgical, mechanical, and topographical aspects, is of paramount importance. Surface roughness, a key indicator of surface texture, directly influences the fatigue life of the component. Employing techniques such as cryogenic cooling with liquid nitrogen can mitigate the temperature in the cutting zone, thereby enhancing surface quality and prolonging component lifespan. In this investigation, the impacts of various dry and cryogenic machining conditions on surface roughness and thermal loads were examined, and the influential parameters were identified.
Author Correction: Enantioselective construction of inherently chiral pillar[5]arenes via palladium-catalysed Suzuki–Miyaura cross-coupling
Gait dysfunction as an early marker of phenoconversion in REM sleep behavior disorder
Abstract Clinical isolated REM Sleep Behavior Disorder (iRBD) is a prodromal stage of α-synucleinopathies such as Parkinson’s disease (PD). Longitudinal changes of gait as a marker of phenoconversion in iRBD have not been systematically evaluated yet. Therefore, twenty-one iRBD patients, nineteen matched healthy controls and fourteen PD patients (H&Y stage I - III) were assessed at baseline using a pressure-sensor walkway (GAITRite). While normalized gait velocity and walking endurance were significantly decreased in iRBD patients compared to controls, gait rhythm parameters such as single support further discriminated PD from iRBD and controls. IRBD patients at imminent risk of phenoconversion within the next 3.7 ± 0.6 years were distinguishable from non-converters by gait rhythm parameters such as single support. Since gait evaluation of our iRBD cohort showed promising results in predicting imminent phenoconversion, future multicenter trials should include gait analysis as an objective assessment of motor function to confirm our results.
Continuously trapped matter-wave interferometry in magic Floquet-Bloch band structures
Abstract Trapped matter-wave interferometry offers the promise of compact high-precision local force sensing. However, noise in the trap itself can introduce new systematic errors which are absent in traditional free-fall interferometers. We describe and demonstrate an intrinsically noise-tolerant Floquet-engineered platform for continuously trapped atom interferometry. A non-interacting degenerate quantum gas undergoes position-space Bloch oscillations through an amplitude-modulated optical lattice, whose resulting Floquet-Bloch band structure includes Landau-Zener beamsplitters and Bragg mirrors, forming the components of a Mach-Zehnder interferometric force sensor. We identify, realize, and experimentally characterize magic band structures, analogous to the magic wavelengths employed in optical lattice clocks, for which the interferometric phase is insensitive to lattice intensity noise. We leverage the intrinsic programmability of the Floquet band synthesis approach to demonstrate a variety of interferometer structures, highlighting the potential of this technique for quantum force sensors which are tunable, compact, simple, and robust.
Enhancement of LTE and NR systems through efficient physical cell identity allocation
Abstract As mobile communication systems continue to evolve to support higher data rates, ultra-low latency, and greater reliability, the effective management of Physical Cell Identities (PCI) becomes increasingly important. The pool of available identifiers is limited—504 in fourth-generation networks and 1008 in fifth-generation networks—so reuse of these identities is unavoidable. Improper reuse can lead to collisions and confusion, resulting in interference, failed handovers, and reduced network throughput. This work addresses these challenges by exploring advanced automated techniques for optimizing PCI. We model the network as a graph, where each cell is represented as a vertex and interference relationships between cells are represented as edges. Using this approach, we implement graph coloring algorithms, including a maximum degree first coloring method, to efficiently assign identifiers and minimize conflicts. We also introduce clustering-based methods, such as Fuzzy hierarchical clustering, to dynamically group cells based on real-time traffic patterns, enabling adaptive management in dense networks. Beyond these deterministic methods, we evaluate metaheuristic approaches, including Biased Random-Key Genetic Algorithms (BRKG), Integer Linear Programming (ILP), and constructive heuristics based on DSATUR. Where they are particularly effective in navigating complex solution spaces to generate near-optimal PCI plans. Our simulation results demonstrate that these modern techniques significantly outperform traditional strategies, reducing identity conflicts by up to 80% and improving key performance metrics such as signal quality, handover success rates, and overall network throughput.
Homogeneous integration of two-dimensional material-based optoelectronic neurons and ferroelectric synapses for neuromorphic vision
Experimental and numerical study on temperature characteristics of geosynthetics-reinforced soil retaining walls in Taklimakan Desert
Tailoring sodium and oxygen mixed-ion conduction in the A-site non-stoichiometric NaNbO3-based ceramics
Abstract Tailoring the electronic or ionic conduction properties of solid-state electrolytes with precision is essential to fulfilling the functional demands of electrochemical energy storage and conversion technologies. Here, the synergistic regulation of Na + and O 2− ions conduction in the Na 0.96 x Ca 0.04 Nb 0.96 Zr 0.04 O 3- δ conductor is achieved by the non-stoichiometric ratio strategy. Crystal structure and electrical property analyses reveal that all samples feature a Pbma orthorhombic structure. With rising Na content, the defect characteristics shift from vacancies to interstitials, the NbO 6 octahedra experience a change from being compressed to normal and then to being obliquely flattened, which leads to an expansion of the corresponding interstitials in the Na-O-Na and Na-O-Nb networks. By changing the structures of these three types of polyhedron and networks, the conduction channels of Na + and O 2− ions as well as electrons can be effectively regulated. The O 2− ions are the main charge carriers for Na-deficient samples, stoichiometric samples feature the mixed O 2− ions and intrinsic electrons, while Na⁺ ions become the dominant carriers for Na-excess samples. This work highlights the important role of lattice defects and oxygen octahedral distortions/twisting on the conductivity, offering insights into the design of and Na + /O 2− ions migration pathways in solid-state ion conductors.
Passive surgical correction of rigid adult spine deformities to normative alignment and balance
Histone lactylation increases CXCL1 expression for neutrophil infiltration and immune escape in pancreatic cancer
A polymer physics model of the interphase cell nucleus for radiobiological simulations
Triple targeting of STING, TGF-β, and PD-L1 boosts CXCL16–CXCR6 signaling for potent antitumor response
Exploring gene expression as a sublethal endpoint in gammarids exposed to pesticides: insights from next-generation sequencing
Multicountry genomic analysis underscores regional cholera spread in Africa
Abstract Cholera remains a significant public health burden in many countries in sub-Saharan Africa, though the exact mechanisms of bacterial emergence and spread remain largely undefined. We generated genomic data from 763 Vibrio cholerae O1 isolates predominantly collected between 2019-2024 to create the largest dataset of V. cholerae genomes sequenced locally in Africa. This dataset enabled us to interrogate recent patterns of spread, including the rapid circulation of the AFR15 lineage associated with unusually large outbreaks in Southern Africa. We provide evidence for the movement of the AFR15 lineage into new African Union Member States and confirm previously observed differences in V. cholerae transmission dynamics in West versus East Africa, though cross-border transmission is prevalent on both sides of the continent. Despite observed differences, evolutionary processes are similar across lineages and we find no evidence for significant changes in antimicrobial resistance genotypes. Overall, our findings emphasize the importance of regionally coordinated cross-border surveillance and interventions, while also demonstrating the critical role of locally generated genomic data in understanding the spread of cholera in Africa.
Engineering polyethylenimine–metal functionalized cryogels for superior catalase binding, activity, and long-term durability
Abstract Cryogels with interconnected macroporous architectures offer significant advantages as enzyme immobilization supports due to their high permeability, mechanical robustness, and tunable surface chemistry. In this study, a novel Poly(HEMA-co-GMA) cryogel was synthesized and subsequently modified through polyethyleneimine (PEI) grafting and transition-metal chelation to create high-affinity matrices for catalase immobilization. Among the metal ions tested with Cu(II), Ni(II), and Co(II), the Cu(II)-functionalized cryogel exhibited superior physicochemical properties, including the highest water retention capacity (438.4%), well-preserved porosity, and strong coordination interactions with amine-rich PEI domains. FT-IR, SEM, TGA, BET, elemental analysis, and ICP-OES results confirmed successful stepwise modification and metal loading. Catalase immobilization studies revealed that the Poly(HEMA-co-GMA)-PEI-Cu(II) cryogel achieved the highest enzyme loading (391.9 mg·g⁻¹), with an optimal immobilization time of 8 h and optimum pH near neutrality. Kinetic analysis demonstrated a substantial decrease in K m (from 57.3 to 14.4 mM), indicating enhanced substrate affinity, while k cat /K m increased 2.8-fold relative to the free enzyme. The immobilized catalase exhibited improved thermal tolerance, strong operational stability (34.2% activity after 15 cycles), high desorption efficiency (96% in the first cycle), and markedly superior storage stability (62.1% activity after 70 days at 4 °C) compared to its free counterpart. These results validate the Cu(II)-chelated Poly(HEMA-co-GMA)-PEI cryogel as a highly efficient and reusable biocatalytic platform with significant potential for industrial and environmental enzyme-based applications.
Fast self-healing in a layered molecular crystal mediated by stress-induced symmetry breaking
Microbial membrane transport genes in maize rhizosphere under fertilization – a preliminary study
Humans are more prosocial in poor foraging environments
Abstract Prosocial behaviours are essential for solving global challenges. Often, these behaviours have been measured using economic games or tasks where people decide between helping or not. However, in everyday life current behaviours are interrupted with alternative opportunities. Across three independent samples (two preregistered, total n = 510), people watched a movie whilst encountering opportunities that benefitted another person or themselves. Crucially, participants decided in different poor and rich foraging environments where the average reward values of opportunities changed. We demonstrate a stronger environmental influence on decisions that benefit others: people were more willing to interrupt their behaviour to help others in poor environments, where the average reward value was lower, compared to richer environments where average reward value was higher. Computational modelling revealed that the opportunity costs of the different foraging environments were valued distinctly for others. Factors of utilitarianism, and empathy/emotional motivation, captured variability in opportunity costs for others. We show that when humans decide to engage in prosocial behaviours depends on the quality of opportunities in one’s environment, which is critical as environments change.