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Reflections on Linear B (part 14) – Sign 76 (with two parallel wavy lines pronounced /ra/); possible derivation from the river traveled nightly by the sun god Ra.
No full textThis article suggests that the two parallel wavy lines in Linear B sign 76 depict the river traveled nightly by the Egyptian sun god Ra. Also:
1. The Egyptian influence was likely exerted already on the Linear A and Cretan hieroglyphic antecedents of Linear B sign 76.
2. Variants of Linear B sign 76 contain a horizontal line across the two wavy vertical lines. The present article suggests the horizontal line might indicate one of the river’s twelve gates that Ra had to navigate through in his nightly journey.
3. But the single line for that one gate was likely an abbreviated form intended to stand for all twelve gates
Waveguide-assisted Single-mode Fiber Bragg Gratings in a Highly Multimode Coreless Fiber Via Femtosecond Laser Inscription for Extreme Temperature Quasi-Distributed Thermal Sensing
No full textThis research reports a potential quasi-distributed thermal mapping optical sensing system for extreme temperatures, leveraging femtosecond (fs) laser inscribed single-mode fiber Bragg gratings (FBGs) and a waveguide within coreless, highly multimode optical fiber, resulting in a single-mode structure. Unlike doped single-mode fibers, coreless fibers composed of silica rods prevent issues associated with dopant migration and ensure data accuracy. The strategic placement of point-by-point FBGs in a cascaded formation on the fs-laser inscribed waveguide facilitates localized multipoint sensing. The long-term stability of the proposed waveguide-assisted FBG system was assessed over 24 hours at elevated temperatures (1000°C), showing no hysteresis during heating and cooling cycles. This approach promotes the use of single-mode waveguide-assisted cascaded FBG systems in extreme temperature environments. The point-by-point FBG writing technique via fs-laser enables rapid inscription compared to the conventional line-by-line method, providing fine control over the grating configuration and ensuring fast bulk production. The proposed device offers comprehensive temperature monitoring suitable for challenging multipoint sensing applications, such as industrial processes operating in extreme conditions
Waveguide-assisted Single-mode Fiber Bragg Gratings in a Highly Multimode Coreless Fiber Via Femtosecond Laser Inscription for Extreme Temperature Quasi-Distributed Thermal Sensing
No full textThis research reports a potential quasi-distributed thermal mapping optical sensing system for extreme temperatures, leveraging femtosecond (fs) laser inscribed single-mode fiber Bragg gratings (FBGs) and a waveguide within coreless, highly multimode optical fiber, resulting in a single-mode structure. Unlike doped single-mode fibers, coreless fibers composed of silica rods prevent issues associated with dopant migration and ensure data accuracy. The strategic placement of point-by-point FBGs in a cascaded formation on the fs-laser inscribed waveguide facilitates localized multipoint sensing. The long-term stability of the proposed waveguide-assisted FBG system was assessed over 24 hours at elevated temperatures (1000°C), showing no hysteresis during heating and cooling cycles. This approach promotes the use of single-mode waveguide-assisted cascaded FBG systems in extreme temperature environments. The point-by-point FBG writing technique via fs-laser enables rapid inscription compared to the conventional line-by-line method, providing fine control over the grating configuration and ensuring fast bulk production. The proposed device offers comprehensive temperature monitoring suitable for challenging multipoint sensing applications, such as industrial processes operating in extreme conditions
A Photosynthetic–respiratory Electron Transport Chain Chimera Based on Photosystem I and Cytochrome C Oxidase on Graphene Oxide
No full textTe self-assembly of enzyme proteins on 2D nanomaterials has enabled the construction and functional control of viable biochemical pathways. However, enzymatic cascades, which combine essential components of the photosynthetic and respiratory electron transport chains in tandem, have thus-far remained elusive. Herein, we have investigated a galvanic biohybrid nano system coupling photosystem I and cytochrome c oxidase on the surface of graphene oxide nanosheets in colloidal suspension. Te oriented immobilization of the enzymes was facilitated by Ni-coordination sites tethered to the carbon basal plane, with negligible parasitic O2 consumption. Transient absorption and electrochemical measurements provided evidence of electron transfer between donors and acceptors, leading to light-induced O2 consumption of up to 70 out of 120 O2 molecules/s/CcO unit. Graphene oxide behaves as an electronic reservoir and as an electroactive support, enabling electron transport, in concert with cytochrome c, as well as small-molecule redox mediators and reductants. This study provides a state-of-the-art approach for the exploration of photoelectron transfer in membrane-free suspensions of nano surface-anchored photosynthetic–respiratory enzymatic chains
Rheological Protocol to Assess and Optimize Latex Coagulation Dynamics for the Thin Glove Coagulant Dipping Process
No full textMany products that directly impact the quality of human life today — gloves, catheters, condoms, and baby bottle teats — are made through the latex-dipping technology. While a variety of methods have been developed – e.g., particle counting, turbidimetry, microscopy, and light scattering – which are suitable for studying the coagulation of latex at very low concentrations, much less work has focused on methods suitable for in-situ characterization of latex coagulation in concentrated solutions (e.g., as relevant to the dipping process). This paper presents a process-relevant rheological protocol for assessing and optimizing latex coagulation dynamics for the thin glove coagulant dipping process. The method involves, first, the use of small amplitude oscillatory rheology to characterize the time-dependent evolution of the viscoelastic properties (e.g., dynamic moduli and phase angle), to quantify the coagulation kinetics. Second, the percolated latex film (after coagulation) is assessed by compressional rheology to evaluate the thickness and elastic modulus. The protocol is herein demonstrated using a commercial-grade carboxylated butadiene-acrylonitrile copolymer (XNBR) latex and nitrate-based coagulant solutions containing various counterions such as calcium, magnesium, aluminum, sodium, and ammonium ions. The results show that the method is sensitive to small changes in ionic speciation, concentration of coagulant formulations, and small changes in temperature. Hence, it can be applied to assess and optimize latex-coagulant formulations and processing parameters for the latex dipping process. While the protocol is demonstrated for an XNBR latex system, its extension to other latex chemistries may require system-specific calibration
Serum Biomarker Trajectory Clusters Predict Functional Outcome and Quality of Life for Traumatic Brain Injury
No full textSerum brain-enriched biomarkers are increasingly employed in the clinical evaluation of traumatic brain injury (TBI) to assist with triage, neuroimaging decisions, and prognostication. However, the potential of temporal biomarker trajectories to inform disease monitoring and long-term outcomes remains underexplored. We aim to identify distinct biomarker trajectory (TRAJ) profiles in traumatic brain injury patients and to examine their associations with long-term clinical outcomes. The study included 373, CT-positive Intensive Care Unit (ICU) traumatic brain injury patients (256 with initial Glasgow Coma Scale 3–12) from the Collaborative European Neurotrauma Effectiveness Research in TBI (CENTER-TBI) core study who had at least two serum samples collected between days 1 and 5 post-injury. Six biomarkers -glial fibrillary acidic protein, ubiquitin C-terminal hydrolase-L1, neurofilament light chain, Tau, S100B, and neuron-specific enolase- were analyzed. Optimal cluster solutions were determined using a composite validation index derived from seven internal clustering metrics. Distinct high and low trajectory classes emerged for all biomarkers; each comprising at least 40% of the cohort for five of the biomarkers. Cross-biomarker concordance analysis identified composite high (n = 104) and low (n = 110) TRAJ profiles. Key metrics for evaluating patient outcomes include Glasgow Outcome Scale Extended (GOSE), mortality, and Quality of Life after Brain Injury Overall Scale (QoLIBRI-OS) at 3, 6, and 12 months as well as a prognostic incremental value analysis using a conventional prediction model: International Mission for Prognosis and Analysis of Clinical Trials in TBI (IMPACT). High TRAJ membership is strongly associated with poor functional recovery (GOSE 1–4 at 3–12 months; odds ratio (OR) 8.79 [95% confidence interval (CI): 4.56-16.97]—12.29 [95%CI: 6.19–24.40], P \u3c 0.001) and increased 180-day mortality (OR (14.84 [95%CI: 5.56–39.64], P \u3c 0.001). Conversely, low TRAJ membership predicted favorable recovery (GOSE 6–8 at 3–12 months; OR 7.42 [95%CI: 3.10–17.76]—10.83 [95%CI: 3.65–32.14], P \u3c 0.001) and better quality of life (QoLIBRI-OS ≥52; OR 4.98 [95%CI: 1.92–12.89], P \u3c 0.01). Compared to single day-1 biomarker measurements, trajectory-based profiles yielded larger effect sizes and provided incremental prognostic value when added to the IMPACT prediction model (ΔR² 9–17%, P \u3c 0.05). Overall, repeated biomarker measurements across the acute phase yield superior prognostic accuracy relative to single timepoint assessments. These findings underscore the importance of integrating longitudinal biomarker monitoring into ICU-based traumatic brain injury care and suggest that temporal trajectory profiling may improve prognostic modelling and facilitate more precise patient stratification for both clinical management and interventional studies
Performance and Mechanistic Insights into Cement Systems Modified with Wastewater-recovered Struvite
No full textStruvite, the stable hydration product and primary strength phase in magnesium ammonium phosphate cement (MAPC), derived from wastewater treatment, has recently been utilized as a sustainable additive to Portland cement (PC). However, its impacts on cement hydration kinetics, pore refinement, rheology, and the mechanisms underlying these processes have not been comprehensively studied. This study developed Portland cement-struvite (PCS) systems by replacing PC with 3–20 % struvite (ST wt.%: PCS3–PCS20) and evaluated these processes using isothermal calorimetry, 3D micro-computed tomography (μXCT), time-dependent rheometry, X-ray diffraction (XRD), and Fourier-transform infrared spectroscopy (FTIR), and the Krstulović-Dabić (K-D) model. The FTIR/XRD confirmed the coexistence of typical PC hydrates and struvite, while μXCT showed a 41.7 % porosity reduction for PCS10 after 28 days. Static yield stress (SYS) increased significantly with ST; PCS10 and PCS15 exhibited 200 % and 351 % higher SYS than the control after 30 min. Plastic viscosity decreased with increasing ST, extending placement windows and improving workability. At the optimal 10–15 % substitution rate, PCS10 (and PCS15) achieved a 5.6 % (6.7 %) and 72.1 % (86.8 %) increase in compressive and flexural strengths, respectively, after 28 days. The K–D modeling showed that all systems followed the NG–I–D mechanisms, with slightly declining rate constants and crystal growth index (n) as ST increased, indicating retardation and a shift in hydrate morphology. The PCS systems rely on filler effects and ST-mediated Ca2+ surface adsorption, promoting early flocculation and reducing porosity. The PCS systems require less water to maintain workability and mechanical strength, without needing flow-modifying additives
Integrated Computational and Experimental Investigation of Groups V and VI Metals in (M,Hf,Ti,Zr)B2-(M,Hf,Ti,Zr)C Ceramics
No full textDual-phase compositionally complex ultra-high temperature ceramics were formulated by incorporating different Groups V and VI metals such as V, Nb, Ta, Cr, Mo, or W into a base composition containing the Group IV elements, Hf, Ti, and Zr. Metal distribution was predicted using first-principles-based thermodynamics simulations and compared with experimental results. Moreover, phase stability, microstructure, and mechanical properties were evaluated for all of the ceramics. Compositions containing Cr, V, Nb, or Ta formed dual-phase ceramics containing only one boride and one carbide phase, while compositions containing Mo or W developed an additional third phase. The experimental metal distribution trends generally aligned with thermodynamic predictions, except for compositions containing V, which showed unexpected segregation behavior that was influenced by complex interactions of the coexistence of boride and carbide structures. From the dual-phase ceramics, the composition containing V exhibited the highest hardness (HV1 = 25.5 ± 0.6 GPa) combined with smaller grain sizes (0.99 ± 0.33 μm for the boride and 1.15 ± 0.31 μm for the carbide phases). Our findings provide insights into phase formation and elemental segregation and help the design of next-generation dual-phase UHTCs with tailored properties
A Fully Discrete Decoupled Scheme and Applications for Non-isothermal Two-phase Flow Model with Different Viscosities and Thermal Diffusivities
No full textTo study natural convection problems in two-phase flows, a non-isothermal two-phase flow model incorporating differential viscosities and thermal diffusivities is considered and analyzed via the phase-field method. This modeling framework involves the Multiphysics coupling of the Cahn-Hilliard phase field equations, heat transfer equation, and Navier-Stokes equations, resulting in a strongly nonlinear system. To efficiently solve the sophisticated system, we develop, analyze, and demonstrate a decoupled linear fully discrete scheme, which leverages the invariant energy quadratization strategy for the Cahn-Hilliard phase field system, the artificial compressibility method without artificial pressure boundary condition, an explicit-implicit treatment of nonlinear terms, and the addition of several key stabilization terms. This scheme is proven uniquely solvable per time step and unconditionally stable. A range of 2D and 3D numerical simulations, including accuracy tests, stability tests, interface pinch off, one or two non-isothermal air bubbles rising, Rayleigh-Taylor instability, and thermal plumes, are carried out to illustrate the model and algorithm\u27s features and broad applicability
An SEIR Model on Time Scales with Discrete Applications to Tuberculosis
No full textIn this paper, we propose a novel dynamical model on time scales consisting of new parameters to investigate the transmission dynamics of tuberculosis (TB), one of the deadliest infectious diseases worldwide, characterized by a long latency stage. The dynamical TB model, governed by the Susceptible–Exposed–Infected–Recovered (SEIR) framework within a unified form, yields a continuous model with a non-saturated incidence rate on the real numbers and discrete models with saturated incidence rates when different time domains are chosen. We analyze the stability of the equilibrium points of both the continuous TB model on the set of real numbers and the discrete TB model defined on the set of numbers separated by h, where the basic reproduction number determines whether an outbreak occurs or the disease dies out. In addition, we demonstrate the significance of the discrete TB model through a numerical analysis guided by our mathematical results and previously estimated parameters from earlier Philippine and South Korea TB data. Through this analysis, we emphasize how the model parameters, particularly the time step h, influence the disease dynamics and lead to biologically relevant results. Our modeling approach and mathematical analysis underline that time scales models can be used to generate novel continuous and discrete models, which are not mere discretization\u27s of a continuous model, and can include new parameters that meaningfully represent practical settings such as data frequency