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An improved united-atom potential for molecular dynamics simulation of saturated properties of n-alkanes
Multiple united-atom (UA) potential models have been developed in the literature to reproduce experimental saturated properties of n-alkanes using Monte Carlo simulations. When these UA potentials are employed in molecular dynamics (MD) simulations, MD simulations often give relatively poor predictions of saturated properties of n-alkanes, particularly the saturated vapor densities, due to the challenges in accurate calculation of long-range intermolecular forces beyond the cutoff distance in an inhomogeneous system. In this work, a new set of UA Lennard-Jones (LJ) interaction parameters for n-alkanes is proposed to reproduce the saturated properties, including saturated liquid and vapor densities (ρf and ρg); saturated vapor pressure (Psat); critical temperature, density, and pressure (Tcr, ρcr, and Pcr); surface tension (γ); latent heat of vaporization (hfg); and saturated liquid viscosity (η) of n-alkanes (C4–C22) using MD simulations with truncated LJ interactions. Compared to the experimental data of n-alkanes properties, the average absolute deviation of the MD simulation results obtained using the improved UA (I-UA) potential developed in this work are 1.6%, 2.3%, 2.8%, 0.3%, 2.7%, 4.3%, 4.4%, 2.1%, and 14.3% for ρf, ρg, Psat, Tcr, ρcr, Pcr, γ, hfg, and η, respectively. The Large-scale Atomic/Molecular Massively Parallel Simulator (LAMMPS) code for MD simulation of liquid–vapor equilibrium of n-dodecane using the I-UA potential is provided in this paper. The LAMMPS code can be easily modified to determine saturated properties of other n-alkanes.
Harnessing Entropic Effects from Interlayer Coupling to Modulate Ion Transport and Rectification in Multilayered Janus Graphene Nanopores
Ablation provides key macronutrients (nitrogen and phosphorous) to glacier ice algae in NW Greenland
Abstract Dissolved phosphorus (P) is thought to limit the growth of glacier ice algae, which darken the surface of the Greenland Ice Sheet (GrIS) and enhance surface melt. This contention is largely based on the low-level of P concentrations, which are often below the limit of detection of conventional methods. Here, we propose that low-level nutrient analysis is essential to understand the macronutrient limitation of glacier algal growth on the GrIS. We sample surface (≤5 cm) and shallow (5−10 and ~80−90 cm depth) ice from two sites in NW Greenland and measure the nano-molar concentrations of dissolved nitrogen (N) and P using a custom-built continuous segmented flow analyser. Quantifiable concentrations of these macronutrients are present, along with glacier ice algal abundances comparable to those of the Dark Zone, a zone of biologically enhanced ice sheet melting. Mass balance calculations for each site indicate that N and P released during seasonal ablation exceed the amounts incorporated into glacier ice algal biomass. These results suggest that dissolved macronutrients are unlikely to limit glacier ice algal growth on the Greenland Ice Sheet.
Engineering application and optimization of a synergistic air curtain–wet vortex dust control system at continuous miner faces
The sensitivity of TANDEM – A new measure of trauma competence
Background Despite international standards outlining the competence areas to be included in educational programs on trauma-informed care, a Norwegian expert group identified a lack of tools to measure the learning outcomes of such programs adapted to the Norwegian context. In response, they developed the Trauma and Development Education Monitor (TANDEM). This study examines the sensitivity of the instrument. Methods The study is based on pre- and post-test survey responses to TANDEM’s 55 items, covering the domains of Readiness, Agency, Reflexivity, Knowledge, Skills, and Work Culture, collected from 370 students across four cohorts enrolled in a three-week trauma course at Oslo Metropolitan University. Confirmatory factor analysis (CFA) with measurement invariance analyses were conducted to evaluate configural, weak, strong, and strict invariance in the reflective dimensions Readiness, Agency, and Reflexivity. Latent growth curve (LGC) models were then applied to analyze changes in outcome scores from pre- to post-program. Finally, LGC levels and changes in outcomes were predicted by participant background variables, i.e., workplace type, target age group, role type, work seniority, and prior trauma training. Findings TANDEM demonstrated sensitivity in detecting significant increases in scores from before to after the course, both for the instrument as a whole and across all domains, most notably for Knowledge and Skills. Some measurement invariance issues were identified in the Agency and Reflexivity domains, indicating interpretation problems. Significant pre–post changes for the total instrument were observed regardless of students’ workplace type, target age group and work seniority, but with greater improvements among those in non-problem focused role types and with less prior trauma training. Implications Overall, TANDEM shows promise as a tool for supporting the implementation, evaluation, and development of trauma competence programs in health and social care contexts. Future developments should test TANDEM across diverse educational, professional, and cultural groups, increase variance in the Readiness domain, refine and validate the domains, and validate the instrument against independent, performance-based competence measures.
Manipulation of plasmonic skyrmions and merons by tuning linearly polarized light
Plasmonic topological quasiparticles are highly promising for multi-channel data parallelization and transmission with the modulation degrees of freedom of polarization, phase, and spin angular momentum. In this study, we propose and demonstrate a polarization-sensitive catenary-shaped nanostructure combined with nano-slits for the generation of plasmonic topological quasiparticles as well as active manipulation of the types. The field distribution of topological quasiparticles measured by near-field scanning optical microscopy with p- and s-polarized light is consistent with a finite-difference time-domain simulation. By analyzing the vector textures and skyrmion number, the generation of plasmonic skyrmion and meron is confirmed, exhibiting the switching between the two topological quasiparticles by rotating the polarization direction of the incident laser.
Dynamic Homogeneous Catalysis Enables Stable and Efficient Aqueous Organosulfur Redox Flow Batteries
A versatile platform for sequential glyco-, phospho-, and proteomics with multi-PTMs integration
Abstract Serial multi-omic analysis of proteome, phosphoproteome, and glycoproteome is pivotal for elucidating drug mechanisms, discovering biomarkers, and identifying therapeutic targets. However, simultaneous multi-level post-translational modifications (PTMs) analysis via parallel processing is hampered by laborious, time-consuming procedures and inconsistent reproducibility. We present an integrated Multi-level PTMs-Proteomic Enrichment platform (MuPPE), enabling sequential glycoproteome, phosphoproteome, and proteome analysis from single biological samples. It combines protein aggregation capture with on-bead digestion and tandem enrichment, achieving superior reproducibility (CV 12.3% vs 17.6% conventional methods) while reducing processing time by 87.5% (4 hours vs 32 hours). MuPPE also enhances coverage, identifying more serum glycopeptides and brain phosphopeptides than other platforms. Applied to aging mouse cohorts, the platform uncovers tissue-specific PTMs remodeling and brain barrier dysfunction. For arsenic mechanisms of action, MuPPE reveals drug-induced PTMs crosstalk between glycosylation and phosphorylation-driven pathway regulation. MuPPE offers a transformative tool for advancing multi-omics insights across precision medicine and disease research.
Assessment of health risks from exposure to indoor volatile organic compounds in European educational buildings
Abstract Volatile organic compounds (VOCs) comprise an important group of indoor air pollutants, commonly found in building materials and consumer products. Due to their low boiling points, VOCs are prevalent in indoor environments, with concentrations in homes, schools, and offices often two to five times higher than outdoors. Chronic exposure to VOCs is linked to a range of adverse health outcomes, including respiratory, neurological, cardiovascular damage, and an increased cancer risk. Children and adolescents who spend a significant amount of time in educational buildings are particularly vulnerable to these effects. Therefore, this study aimed to estimate the related health risks to those in day care centres, schools, high-schools and universities across 17 member states of the European Union (EU) by utilizing a previously published dataset and collecting data on levels of 9 VOCs. Health risks were assessed using the World Health Organization’s Indoor Air Quality Risk Calculator. Point of departure indices (PODIs) and cancer risks were calculated, with values above 1.0 and 10 cases/1 million population respectively indicating an increased health risk. Our results showed that formaldehyde exposure poses an increased risk of respiratory, neurological and carcinogenic effects in educational buildings in 14 of the countries studied. Additionally, neurological risks from exposure to benzene were above the limit in 4 EU countries. These findings indicate the need to reduce formaldehyde and benzene concentrations in European educational buildings to protect the health of the next generation.
Tissue-specific mitochondrial pathway remodeling linked to longevity in honeybee queens
Mitochondrial metabolism plays a critical role in determining lifespan across animal taxa. In our study, we used the Western honeybee ( Apis mellifera ) as a model, capitalizing on the stark lifespan difference between queens, which often live more than two years, and summer workers, which survive only about 30 days, despite sharing the same genetic background. We investigated mitochondrial function in head tissue, thoracic muscle, and abdominal fat tissue of queens and workers, comparing early (7 days) and late adult stages (28–30 days in workers; 2 years in queens). No significant differences in mitochondrial flux control ratio for the NADH- Succinate- and glycerophosphate (Gp) pathways were found in thoracic muscles across castes or age groups. In head and abdominal fat tissues, early-life queens showed reduced reliance on NADH-linked pathways for maximal respiratory flux compared to workers. The decrease in the NADH-pathway was compensated by an increase in the Gp-pathway contribution. Queens exhibited reduced phosphorylation-pathway control over OXPHOS compared to workers, both in head tissue during early life and in abdominal fat tissue later in life. These findings reveal caste- and tissue-specific patterns of mitochondrial regulation that may contribute to dramatic lifespan divergence observed in eusocial insects. They suggest that early-life metabolic flexibility could play an important role in shaping life history evolution in Apis mellifera .
Theoretical analysis of the electron paramagnetic resonance spectra of the moderately coupled chromophore-radical conjugate
A theoretical study of transient electron paramagnetic resonance (TREPR) spectra of rigidly linked chromophore–paramagnetic species, in which the magnitude of the exchange coupling J between the two species is noticeable but smaller than the zero field splitting (ZFS), is presented. The TREPR spectrum of these conjugates is too complex to be characterized by two ZFS parameters (D and E). The spectral characteristics derived from this study provide practical tools for differentiating intersystem crossing (ISC) mechanisms and estimating exchange interaction strengths. This has the potential to aid in identifying the D/J-dominant coupling regime. When the chromophore’s D-parameter is strong compared to other spin–spin interaction terms, the spectral properties can be classified into three regions: the central region around the resonance fields Bres near the spectrum’s center B0 (Bres≈B0), the mid regions (Bres≈B0±D/2), and the outer regions (Bres≈B0±D). Analytical expressions are obtained for magnetic fields aligned along one of the chromophore’s principal axes. Sharp peaks near the center of the spectrum split by ∼4 J arise when radical-enhanced ISC is efficient. This makes them a unique marker that distinguishes this mechanism from the triplet mechanism of ISC.
Photoaffinity Labeling Strategy Reveals Tetraspanin CD9 as a Transient Target of Anticancer Yaku’amide B
Dual Cation/Anion Binding in Crown Ether-Based Coordination Cages
Endothelial PDLIM5 promotes tip cell filopodia formation and tumor angiogenesis by regulating ACTN1/ACTN4-dependent actin bundling
The effect of fentanyl combined with linezolid on in-hospital mortality in mechanically ventilated patients: A retrospective cohort study
Background The combination of linezolid and opioid drugs such as fentanyl may increase the risk of serotonin syndrome, but its impact on in-hospital mortality is not yet clear. The aim of this study is to investigate the effect of simultaneous use of fentanyl and linezolid on in-hospital mortality in mechanically ventilated patients. Method Based on the MIMIC-IV database, 3339 patients receiving mechanical ventilation were enrolled and divided into three groups: the group receiving linezolid simultaneously (n = 43), the group receiving linezolid within 14 days (n = 22) and the group that did not use linezolid (n = 3274). Use multivariate Cox regression analysis to analyze in-hospital mortality rates and adjust for confounding factors. Result The in-hospital mortality rate of the group receiving linezolid simultaneously was 37.2% (16/43), the group receiving linezolid within 14 days was 40.9% (9/22), and the group that did not use linezolid was 22.9% (751/3274). The in-hospital mortality rate of the group receiving linezolid simultaneously was significantly higher than that of the group that did not use linezolid (hazard ratio [HR], 1.56; 95% CI, 1 ~ 2.43; P = 0.049). There was no statistically significant difference in in-hospital mortality rate among the group receiving linezolid within 14 days and the group that did not use linezolid (hazard ratio [HR], 1.01; 95% CI, 0.5 ~ 2.05; P = 0.968). Subgroup analysis showed that there was no interaction between different groups at baseline (age, gender, race, BMI, liver disease, and kidney disease) (interaction p-value > 0.05). Conclusion In this post-hoc analysis, we found an association between the combined use of fentanyl and linezolid and increased in-hospital mortality among mechanically ventilated patients. However, this finding is based on studies with small sample sizes and requires further validation through larger, multicenter investigations. In clinical practice, the potential risks of this drug interaction should be carefully evaluated.
Isotopologues of the NeHCl complex observed by chirped pulse Fourier transform microwave spectroscopy
The weakly bound Ne·HCl van der Waals dimer is a prototype for studying large-amplitude motion in noncovalently bound systems. We report the microwave spectrum of eight isotopologues of Ne·HCl, five of which have not previously been observed by high-resolution spectroscopy. We examine trends in experimentally derived van der Waals stretching force constants and effective bond lengths that are strongly sensitive to isotopologue-dependent motional averaging along the hindered rotation coordinate. Finally, we report an updated semi-empirical three-dimensional morphed potential for the Ne·HCl dimer that is fitted to a large dataset including previous microwave, near-IR, and sub-millimeter wave data in addition to our new microwave data.
The climate opportunities and risks of contrail avoidance
Abstract Navigational contrail avoidance presents an opportunity for rapid reduction in aviation-attributable warming. Here, we use the Aviation Climate and Air Quality Impacts model to evaluate the global temperature changes associated with contrail avoidance towards 2050. If no avoidance is adopted, aviation is projected to contribute 0.040 K of CO 2 warming and 0.054 K of contrail warming by 2050. The combined warming from aviation CO 2 and contrails is 19% of the difference between current temperatures and the +2 °C limit above pre-Industrial levels, i.e. 19% of our remaining temperature budget. An avoidance strategy phased in over 2035-2045 may recover 9% of this budget, but a 10-year delay may reduce this to 2%. The warming due to additional CO 2 emitted during avoidance is two orders of magnitude lower than the expected contrail warming reduction. For every year of delay, the world will be on average 0.003 K hotter in 2050. The most significant climate risk associated with contrail avoidance is therefore inaction.
Transscleral photodynamic therapy with a chlorin e6: An experimental study of exposure parameters and therapeutic window
Purpose To define optimal exposure parameters and the therapeutic window for transscleral photodynamic therapy (TSPDT) with chlorin e6 by evaluating clinical, histological, and thermal effects of subthreshold, therapeutic, and suprathreshold settings in rabbit eyes. Methods The study was conducted on 21 healthy rabbits. TSPDT was performed using a 660 nm laser and chlorin e6 (2.5 mg/kg). Transscleral probes (5 mm: 0.1 W, 0.17 W, 0.3 W; 10 mm: 0.3 W, 0.6 W) with integrated thermosensors were used. Enucleation and histological analysis were performed 14 days post-irradiation. Results Fundus examination on day 14 revealed distinct treatment zones correlating with laser settings. The therapeutic window was defined as 0.14–0.17 W (5 mm probe; power density: 0.693–0.866 W/cm²; energy density: 415.8–519.6 J/cm²) and 0.48–0.6 W (10 mm probe; 0.611–0.764 W/cm²; 366.6–458.4 J/cm²) with 600 s exposure time, achieving selective choroidal damage without scleral or retinal injury (ΔT ≤ 4.5°C). Suprathreshold settings (≥0.3 W for 5 mm; ≥ 0.6 W for 10 mm) induced retinal necrosis (up to 50%) and scleral coagulation (ΔT ≥ 8°C) with power densities exceeding 0.866 W/cm² (5 mm) and 0.764 W/cm² (10 mm). Conclusion TSPDT with chlorin e6 enables selective targeting of intraocular pathological tissues while preserving scleral and retinal integrity. Defining the therapeutic window and using real-time thermal monitoring enhances treatment safety. These findings lay a foundation for clinical protocols for uveal melanoma and other intraocular tumors.
Toward rational understandings of the oxygen reduction reaction on Fe–N–C single-atom catalysts
Rationalization of experiments of oxygen reduction reaction (ORR) on Fe–N–C single-atom catalysts (SACs) is essential to reveal the underlying mechanism. While extensive investigations have been carried out, it is still challenging for theoretical simulations to accurately describe experimental observations, owing to the complexities in both experiments and simulations. In addition, the predictive ability of the activity descriptor is limited by its insufficient connection with experimental measurements. In this work, by using first-principle calculations and microkinetic simulations, we systematically study the ORR on Fe–N–C sites in various chemical environments. A theoretical scheme is first established that simultaneously takes account of the *O2 adsorption, the Hubbard correlation of Fe 3d electrons, the solvent effect, and the kinetic factors to rationalize relevant experiments. Using this scheme, we then investigate the influence of axial ligands and adjacent site on the ORR activity of Fe–N–C. We find that the covered axial ligands result in activity enhancement on pyridinic FeN4C10 and activity reduction on pyrrolic FeN4C12, respectively, clarifying the better durability of pyridinic FeN4C10. In addition, the activity of the Fe–N–C site is degraded by the adjacent one when inter-site distance is too small. Finally, a three-dimensional (3D) diagram is constructed to predict the experimentally measurable half-wave potential as a function of the adsorption free energies of *OH and *O2, which can provide a unified description of the ORR activity trend. The 3D diagram can be extended to other SACs and metal (111) surfaces. This work demonstrates the significance of assessing the microkinetics in deeper insights and provides comprehensive guidance for rational catalyst design.