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Solid-state bioreactors for efficient energy recovery from gaseous waste streams

Blocking the m6Am methyltransferase PCIF1 releases STAT1-mediated Th1 immunity to potentiate cancer immunotherapy

Yield Smarter, Not Harder: Good Practices for Machine Learning of Reaction Outcomes

Response surface modeling of oxidized polyethylene drag reduction for hydraulic fracturing

Abstract Hydraulic fracturing operations require precise control of friction-reducer dosage to minimize pumping costs, yet the nonlinear coupling between polymer concentration, flow rate, and drag reduction (DR) efficiency remains difficult to predict quantitatively. To address this gap, the present study develops a predictive Response Surface Methodology (RSM) framework for optimizing the DR performance of oxidized polyethylene (1 MDa) in aqueous fracturing fluids. Using a closed-loop pipe flow system (inner diameter 3 cm, test length 10 m), a central composite design (CCD) was executed over the parameter space of polymer concentration (200–600 ppm) and volumetric flow rate (10–50 L/min) at 20 ± 0.5 °C. The resulting quadratic regression model correlating DR% with the two factors is statistically highly significant ( p  < 0.01, R 2 = 0.985, Adj. R 2 = 0.961). The RSM model predicts an optimum DR% of ~ 69.3% at a polymer concentration of ~ 376 ppm and a flow rate of ~ 33 L/min (Re ≈ 35 000), which is experimentally bracketed by the center-point confirmation run (400 ppm, 30 L/min, measured DR% = 69.0%). Validation experiments confirm a prediction error below 2%, and scale-up analysis via empirical scaling laws projects a DR% of 59% under field-relevant conditions (Re = 100 000, large-diameter pipe). Furthermore, temporal degradation tests reveal that DR performance decays exponentially under continuous circulation (first-order rate constant k = 0.045 min −1 ), declining from 70% to 45% within 20 min. These findings provide a reproducible, data-driven basis for real-time dosage optimization and operational fluid management in hydraulic fracturing.

Adult-to-infant unidirectional neural coupling mediates selective social learning in infants from the United Kingdom and Singapore

Precise Fusion of Conjugated Organoboranes: A Tetraboron-Doped Molecular Carbon with Narrowband Fluorescence and Microscale Lasing

Navigating Inner Helmholtz Plane Reactions Enables Robust Lithium Metal Anodes for 500 Wh kg ^-1 Pouch Cells

Noncovalent Macrocyclic Encapsulation via Terminal “Dynamic Locking” Enabling High-Performance Nonfused Ring Electron Acceptors

Identification of columnar aerosol types and seasonal disparity over urban sites in the Indo-Gangetic Plain using a Gaussian Mixture Model

Non-local synchronization of continuous time crystals in a semiconductor

Abstract Synchronization resulting in unified collective behavior of the individual elements of a system that are weakly coupled to each other has long fascinated scientists. Examples range from the periodic oscillation of coupled pendulum clocks to the rhythmic behavior in biological systems. Here we demonstrate this effect in a solid-state platform: spatially remote, auto-oscillating electron-nuclear spin systems in a semiconductor. When two such oscillators separated by up to 40 μ m are optically pumped, their individually different frequencies lock to a common value, revealing long-range coupling. For larger separations, the synchronization breaks. The interaction distance matches the electron spin diffusion length, identifying spin transport as the coupling-mediating mechanism and maintaining correlated behavior over mesoscopic distances. As a consequence, a wide-area optical pump drives all oscillators within the illuminated spot into a single synchronized state, despite their inhomogeneity. This synchronization accounts for the exceptional stability of the resulting auto-oscillations, enabling collective motion in distributed spin systems and paving the way toward spin networks in spintronics.

Extremozymes-Inspired Catalyst for Epoxide-Based Polymerization

Synergetic 3D Jones-matrix imaging of multifractal hierarchies in optically anisotropic biological soft matter

Model-based semantic distance reveals adaptive coordination of distinct cognitive systems in flexible knowledge retrieval

Mechanically Interlocked Double-Walled Covalent Organic Framework with Cucurbit[8]Uril-Stabilized Viologen Radical Dimers

Negatively Curved Chiral Bilayer Nanographene

Mid-term clinical and radiologic outcomes of augmented microfracture with decellularized particulated costal allocartilage for knee cartilage defects: four-year prospective case series

MAX3 deficiency recruits protective Pseudomonas via modulating the SL-ABA-flavonoid axis to suppress soil-borne pathogen infection

Correction to “Framework Short-Range Order Observed in a Spinel-Type Li Superionic Conductor”

Exploratory analyses of potential moderators of a personalized intervention to reduce preoperative anxiety: a secondary analysis of a randomized clinical trial

Abstract This exploratory secondary analysis investigated whether individual patient characteristics might moderate the effectiveness of a personalized, information-based intervention aimed at reducing preoperative anxiety. The study included 122 patients scheduled for elective surgery. Anxiety was assessed repeatedly before surgery using the Amsterdam Preoperative Anxiety and Information Scale alongside numeric rating scales, capturing surgery-related anxiety, anesthesia-related anxiety, and overall anxiety. Constrained linear mixed models were applied to evaluate potential moderating effects of sociodemographic (e.g., education), psychological (e.g., neuroticism, depression, need for information, perceived physician competence and warmth), and clinical variables (e.g., smoking status, previous surgeries, type of surgery, chronic pain, premedication). The intervention consisted of a structured conversation supplemented by optional video material. The analyses provided little evidence that intervention effects systematically differed according to the examined patient characteristics. Among the examined moderators, chronic pain yielded the strongest indication of potential effect modification with regard to anesthesia-related anxiety outcomes. However, these findings did not remain statistically significant after correction for multiple testing and should therefore be considered exploratory and hypothesis-generating. Overall, the present findings provide no confirmatory evidence that the effectiveness of the intervention differs systematically across the examined patient characteristics. Future adequately powered studies are needed to determine whether specific patient characteristics influence response to personalized preoperative anxiety interventions.

Stretching decelerates ring-opening metathesis at cis-olefins in stressed molecular bows