Increase In Concentration Research Articles

Lipoxin A4/FPR2 Signaling Mitigates Ferroptosis of Alveolar Epithelial Cells via NRF2-Dependent Pathway During Lung Ischemia-Reperfusion Injury.

Post-lung transplant (LTx) injury can involve sterile inflammation due to ischemia-reperfusion injury (IRI) that contributes to allograft dysfunction. In this study, we investigated the cell-specific role of ferroptosis (excessive iron-mediated cell death) in mediating lung IRI and investigated if specialized pro-resolving mediators such as Lipoxin A4 (LxA4) can protect against ferroptosis in lung IRI. Single-cell RNA sequencing analysis of lung tissue from post-LTx patients was performed, and lung IRI was evaluated in C57BL/6 (WT), formyl peptide receptor 2 knockout (Fpr2-/-) and nuclear factor erythroid 2-related factor 2 knockout (Nrf2-/-) mice using a hilar-ligation model with or without LxA4 administration. Furthermore, the protective efficacy of LxA4 was evaluated employing a murine orthotopic LTx model and invitro studies using alveolar type II epithelial (ATII) cells. The results show differential expression of ferroptosis-related genes in post-LTx patient samples compared to healthy controls. A significant increase in the levels of oxidized lipids and a reduction in the levels of intact lipids were observed in mice subjected to IRI compared to shams. Importantly, LxA4 treatment attenuated pulmonary dysfunction, ferroptosis, and inflammation in WT mice subjected to lung IRI, but not in Fpr2-/- or Nrf2-/- mice after IRI. In the murine LTx model, LxA4 treatment increased PaO2 levels and attenuated lung IRI. Mechanistically, LxA4-mediated protection involves an increase in NRF2 activation and glutathione concentration as well as a decrease in MDA levels in ATII cells. In summary, our results collectively show that LxA4/FPR2 signaling on ATII cells mitigates ferroptosis via NRF2 activation and protects against lung IRI.

Effects of Ag Doping Concentrations on Structural and Optical Properties of Citrus Reticulata Capped ZnO Nanoparticles

Dopants are used to modify the properties of metal oxides. They are classified into p type and ntype. The p type dopants are electron acceptors and they reduce the bandgap energy. The n- type dopants are electron donors. Ag+ have two characteristics features such that they can be used in place of substitution and interstitial. Citrus reticulata capped silver doped zinc oxide nanoparticles (AgZnONPs) were synthesized via chemical precipitation method, with Citrus reticulata acting as capping, reducing and stabilizing agents. The nanoparticles were synthesized at different doping concentrations of silver (Agx-ZnO) (x=0.1, 0.25, 0.5, 0.75, 1.0, 1.5, and 2.0 %). The effects of different dopant concentration on structural and optical properties of Citrus reticulata capped ZnO nanoparticles were investigated using X-ray diffraction (XRD), Ultra Violet- Visible spectrophotometer (UV-Vis), Fourier transform Infrared spectroscopy (FT-IR) and Photoluminescence (PL) spectroscopy. The XRD pattern obtained showed that hexagonal wurzite structure of ZnO nanoparticles was retained on addition of Ag as a dopant. 0.1% Ag-ZnO displayed highest peak in XRD pattern at plane [101]. The crystal size of the nanoparticles ranged from 15.2919.87nm. At 0.5% Ag-ZnONPs, the XRD peak shifted to higher 2 theta degrees compared to other doping concentrations. The bandgap energies of Ag-ZnONPs were estimated using Tauc’s plot. The bandgap energies were observed to decrease with increase in Ag doping concentration. 0.25% AgZnONPs had a bandgap energy of 3.69eV and that of 2.0% had a bandgap energy of 3.03eV. FT-IR spectra showed absorption in both functional group and fingerprint regions. The absorption band between 420- 470cm-1 is associated with that of the metal oxide. The PL spectrum showed emission at a wavelength of 350- 500nm. The optical properties predict the possibility of using of Ag-ZnONPs in solar cells and optoelectronics.

Three-dimensional internal deformation measurement methods for hydrogels based on optical coherence tomography

Abstract Depth-resolved, non-contact, full-field three-dimensional (3D) deformation measurement is essential for the application of hydrogels in biomimicry, soft robotics, and optical components. However, current methods are constrained to surface measurements and encounter difficulties in underwater settings. Leveraging the 3D and depth-resolved imaging capabilities of optical coherence tomography (OCT), we propose an OCT-based method for measuring 3D deformation of hydrogels in water. This method integrates underwater electrically driven devices with a Limited-memory Broyden-Fletcher-Goldfarb-Shanno (L-BFGS) based digital volume correlation (DVC) algorithm for 3D strain measurement. We conducted virtual tensile tests and underwater rigid body translation tests to validate the method. The results demonstrated that the strain calculation algorithm had an error of less than 80με and the system error for underwater strain measurement was less than 800με. Utilizing this innovative approach, we measured the 3D displacement and strain distributions within Carbon Nanotube (CNT)/Poly (acrylic acid/acrylamide) (CNT/P(AA/AM)) electro-responsive hydrogel samples. These samples were immersed in solutions of differing ionic concentrations and exposed to a range of direct current (DC) electric fields. We discovered that when subjected to electric fields ranging from 1 to 3 volts, the central region of the hydrogel experiences tensile deformation along the direction from electrode to another. However, when the electric field strength is increased to between 4 and 5 volts, the deformation transitions to a compressive state. Additionally, an increase in NaCl concentration results in a decrease in the overall deformation of the hydrogel. In addition, uniaxial tensile tests were carried out on polyvinyl alcohol (PVA) hydrogels underwater to further verify the method. It was demonstrated that the method can accurately capture the internal deformation field of notched PVA hydrogels in solution under uniaxial tension. The integrated OCT-DVC method offers a novel experimental framework for precise 3D deformation measurement and analysis of semi-transparent hydrogel mechanical behavior in liquid environments.

Liquid Crystal Cubic Phases Constructed from Sophorolipids Micelles.

Biosurfactants are considered to be desirable alternatives to synthetic surfactants. Sophorolipids produced by nonpathogenic yeast strains are one of the main types of glycolipid biosurfactants and have various applications. In this work, the aqueous phase behavior of the glycolipid-based biosurfactant sophorolipids (SL) was investigated using polarized microscopy, small-angle X-ray diffraction (SAXS), nuclear magnetic deuterium spectroscopy (2H NMR), transmission electron microscopy (TEM), freeze-etched transmission electron microscopy (FF-TEM), and dynamic light scattering (DLS). The binary phase diagram of the SL/H2O system was constructed, and a liquid crystalline cubic phase constructed by sophorolipids micelles was observed. A micellar phase at low concentrations (<50 wt %) was found. As the concentration increases, after a transition phase, it is a strictly micellar cubic phase at concentrations up to 70 wt %. The micellar cubic phase is an isotropic, highly viscous liquid crystal composed of three-dimensionally ordered arrangements of spherical micelles, which are arranged in simple cubic (CubI/Pm3m) or body-centered cubic (CubI/Im3m). The rheological properties at different concentrations and temperatures were studied. The micellar cubic phase is highly viscoelastic, and the viscosity tends to decrease uniformly with increasing temperatures (15-90 °C) and then returns to its original state after cooling, indicating that the micellar cubic phase possesses satisfactory reversibility at high temperature. The results are expected to be instructive for the application of the sophorolipids.

Fe and Cu co-doping induces abundant oxygen vacancies in MnO2 for efficient ozone catalytic oxidation of toluene at room temperature.

MnO2 holds significant potential for room-temperature ozone catalytic oxidation of volatile organic compounds (VOCs), yet it encounters challenges related to low degradation efficiency. This study introduces a co-doping strategy aimed at enhancing the catalytic activity and stability of MnO2. Specifically, Mn4+ ions were substituted with low-valence copper and iron dopants via a straightforward one-step hydrothermal method, resulting in the formation of abundant oxygen vacancies on the catalyst surface through driven redox precipitation. The resultant Fe-Cu-MnO2 catalyst exhibited remarkable catalytic performance at room temperature, achieving 100% toluene degradation and 100% ozone removal efficiency, along with an impressive mineralization ratio of 81.2% and sustained stability over 100 hours. Relevant experiments demonstrated that the improvement in catalytic activity was primarily attributed to the significant increase in oxygen vacancy concentration induced by co-doping. This was accompanied by increased surface oxygen adsorption and enhanced low-temperature reducibility, which facilitated the generation of reactive oxygen species. Additionally, co-doping induced crystal morphology changes and specific surface area expansion contribute to exposing more active sites, thereby enhancing catalytic performance. Consequently, the catalyst exhibited superior ozone catalytic oxidation performance for toluene degradation. In situ DRIFTS analysis further elucidated the degradation pathway and reaction mechanism of ozone catalytic oxidation of toluene. These findings may provide valuable insights for the development of efficient catalysts for low-temperature catalytic ozonation of VOCs.

Experimental determination of giant polarization in wurtzite III-nitride semiconductors

Polarization engineering has revolutionized the photonic and electronic landscape of III-nitride semiconductors over the past decades. However, recent revelations of giant ferroelectric polarization in wurtzite III-nitrides challenge the long-standing paradigms. Here, we experimentally elucidate the polarization, including its magnitude and orientation, and its relationship to lattice polarity in III-nitrides. Those experimentally determined polarizations exceeding 1 C/m2 with an upward orientation in metal-polar wurtzite nitride compounds align with recent theoretical predictions. To reconcile these findings, a unified polarization framework is established based on the centrosymmetric layered-hexagonal reference structure. This unified framework redefines the polarization landscape in contemporary GaN heterostructures, quantum structures, and ferroelectric heterostructures. Furthermore, we predict significant tunability and a dramatic increase in sheet carrier concentration in ferroelectric ScAlN/GaN heterostructures, heralding advancements in high-power, high-frequency, and reconfigurable transistors, and non-volatile memories. This work bridges the critical gap in the understanding of polarization in both conventional and ferroelectric wurtzite nitrides, offering fundamental insights and paving the way for next-generation photonic, electronic, and acoustic devices.

Thermal radiation and Hall current effects on Williamson non-Newtonian peristaltic flow in a debris-encrusted ureteral tube: simulation of urological radiation therapy

ABSTRACT Peristaltic contractions in the ureter occur 1–5 times per minute and can be disrupted by various physical and mechanical irritants. The carrier fluid, urine, is modelled as a non-Newtonian fluid, specifically following the Williamson model. This research presents a theoretical and computational investigation of a steady magnetohydrodynamic non-Newtonian fluid. Appropriate scaling variables are utilized to transform the partial differential equations governing the momentum and energy conservation for both phases and the associated boundary conditions into a dimensionless system. Axial velocity, stream function, and pressure gradient are obtained via perturbation methods, while temperature and concentration profiles are solved exactly. This article highlights several novel aspects of the dynamics of the ureter in two-phase conditions, which are relevant to the usage of magnetic therapy and thermal radiation techniques. The Williamson fluid’s elastic nature reduces the resistance to flow and pressure buildup. The findings also demonstrate that the mean axial velocity of the fluid phase diminishes as particle concentration increases; however, the contrary trend is observed due to improved convective heat transfer, which lowers the temperature surrounding the particles. By accounting for heat transmission, this study supports heat-dose sensitivity tests essential for improved Chronic Kidney Disease (CKD) treatment. ζ

Effect of polystyrene nanoplastics on its toxicity and reproduction in Philodina roseola

Micro-nano plastics have emerged as a major ecological concern. The nanoplastics (NPs) pose a huge threat to microscopic animals. Our study aims to decipher the effect of polystyrene nanoplastics (PSNPs) of 50 and 100 nm sizes on a bdelloid rotifer (Philodina roseola). Both sizes of PSNPs were analyzed using field emission Scanning electron microscopy, Fourier transform Infrared spectroscopy, and Dynamic light scattering analyses. The LC50 values for 50 and 100 nm PSNPs at 48 h upon interaction with the rotifers were 16.36 and 22.94 mg/L respectively. The total protein and superoxide dismutase levels decreased with an increase in concentration in both PSNPs upon interaction at various concentrations (4, 8, 12, and 16 mg/L). Whereas the lipid peroxidase and reactive oxygen species levels increased with an increase in concentration for both PSNPs at similar concentrations. Further, both PSNPs were found to cause internal organ damage in rotifers. A delay in the hatching rate was observed when the rotifers interacted with both PSNPs in addition to the decrease in the hatching rate of F1 generation. Therefore, PSNPs pose a threat to the natural life cycle in the rotifers.

Impact of the inoculum effect on cefepime activity against AmpC-hyperproducing Enterobacter spp.: insights into resistance mechanisms.

Antimicrobial resistance among Enterobacter spp. is a significant concern in healthcare settings due to their ability to hyperproduce AmpC β-lactamase, thereby limiting therapeutic options. Cefepime is recommended for treating these infections; however, its efficacy might be compromised under high bacterial inoculum conditions. To evaluate the inoculum effect of cefepime on AmpC-hyperproducing Enterobacter spp. clinical isolates. MICs were determined in 62 Enterobacter spp. clinical isolates using broth microdilution at standard (5 × 105 cfu/mL) and high (5 × 106 cfu/mL) inocula. The inoculum effect was defined as an 8-fold or greater MIC increase. Kaplan-Meier survival analysis and time-kill assays were conducted, and β-lactamase activity was measured to investigate the mechanism. At standard inoculum, cefepime showed a MIC50 of 1 mg/L and a MIC90 of 8 mg/L. High inoculum conditions resulted in a significant increase in MIC50 (8 mg/L) and MIC90 (256 mg/L), with an inoculum effect observed in 61.3% of isolates. This effect led to a substantial rise in cefepime-resistant isolates, from 6.5% to 54.8% (P < 0.001). Kaplan-Meier analysis confirmed a 16-fold increase in median inhibitory concentration under high inoculum conditions. Time-kill assays and β-lactamase activity measurements revealed that isolates with the inoculum effect displayed significantly higher β-lactamase activity, contributing to cefepime hydrolysis and resistance. These findings highlight the critical impact of bacterial inoculum size on cefepime efficacy in AmpC-hyperproducing Enterobacter spp. infections. Tailored antimicrobial strategies are needed, especially for infections with high bacterial loads, to optimize clinical outcomes and minimize resistance development.

Local Structure and Ionic Diffusion in LiF-BeF2-ThF4 Molten Salts: Insights from Ab Initio Molecular Dynamics.

Understanding the local structure and ionic diffusion in LiF-BeF2-ThF4 (FLiBeTh) is critical for designing fourth-generation nuclear reactors. However, high-temperature experiments with these salts are often associated with radioactivity and toxicity. Computational simulations provide a safe and efficient method for exploring these materials. In this study, ab initio molecular dynamics (AIMD) simulations were used to analyze the 2LiF-BeF2 system with ThF4 additions ranging from 0 to 18.18 mol % at 973 K. We calculated the radial distribution function (RDF), angular distribution function (ADF), coordination number (CN), mean square displacement (MSD), and anion residence ratio r(t) to investigate the impact of ThF4 concentration on the local structure and ionic diffusion. We found that increasing concentrations of ThF4 have little impact on the structure of the cation first coordination shells. The RDF indicates short-range order in the structure of the molten salts. Additionally, the CN and its distribution indicate that Li+ is primarily tetra- and penta-coordinated, Be2+ is tetra-coordinated, and Th4+ is octa-coordinated. ADF analysis reveals that while the first coordination shells of Be2+ tend toward a regular tetrahedral configuration, Li+ exhibits a distorted octahedral structure, often with one or two anionic cavities. In terms of ionic diffusion, the mean square displacement (MSD) indicate that ionic diffusion rates order as follows: Li+ > F- > Be2+ > Th4+. The r(t) indicates that Be-F coordination shell is the most stable, followed by Th-F, with Li-F being the most dynamic. As ThF4 concentration increases, there is a decrease in the total MSD of the molten salt, suggesting a reduction in overall ionic diffusion. The results from the AIMD simulations align closely with experimental and other simulation data, thereby confirming the reliability of this work. Overall, this study provides insights into the FLiBeTh molten salt, supporting the development of fourth-generation nuclear reactor fuels.

Significantly enhancing current carrying performance of MgB2 superconductor with natural dopants carbon nanoparticles and rare earth elements derived from Dicranopteris pedata waste

Abstract Carbon doping has always played an irreplaceable and important role in improving the performance of MgB2 superconductors. However, the excessive suppression of Tc by carbon element and its excessive accumulation at grain boundaries make it difficult to realize its potential to enhance the performance of MgB2 in the preparation of practical materials. In addition, introducing magnetic flux pinning centers that are more effective than interface pinning is another challenge faced by MgB2. In this study, a mixture of carbon nanoparticles and trace rare earth elements (CNPs/REEs) obtained from high-temperature calcination of dicranopteris pedate waste was used as a dopant, which can effectively introduce an appropriate amount of carbon into the MgB2 lattice in short-term low-temperature reactions to enhance the irreversibility field (Hirr) of MgB2. Moreover, the residual carbon nanoparticles and rare earth impurities that have not entered the lattice can be highly dispersed in MgB2, serving as point pinning centers, and at the same time, limiting the growth of MgB2 particles, which further strengthens the role of grain boundary pinning force. The synergistic consequence of these doping effects leads to a significant increase in Jc throughout the entire magnetic field range (0-10 T) at 4.2 and 20 K. As a result, Jc@3T at 4.2, 10 and 20 K increased from 90, 41, and 10 kA/cm2 of the undoped MgB2 to 230, 87, and 20 kA/cm2 of the C-005 sample, respectively. At 20K, the Hirr value reached more than 5T (doping amount x=0.05). It was also found that the irreversibility field is governed by the giant flux creep characteristic as the dopant concentration increases and the main pinning mechanism of the doped samples is still the grain boundary pinning.

Abstract 5902: Quantification of the effect of early-stage cancer on cell-free DNA levels in plasma

Abstract Elevated cell-free DNA (cfDNA) levels are often observed in cancer patients. However, the exact effect of cancer on cfDNA concentration is not fully understood. In order to obtain insight into cfDNA dynamics in the presence of early-stage cancer, we analyze a rich, previously published dataset of cfDNA in healthy individuals and patients with stage I-III lung, breast, colorectal, pancreatic, ovarian, esophageal, stomach and liver cancer. We find that, despite the high variance of cfDNA levels among both healthy individuals and cancer patients, early-stage cancer exhibits a systemic effect resulting in a multiplicative, cancer-type specific increase in cfDNA concentration originating from healthy tissue. For each cancer type, we also observe similar multiplicative increases in the concentration of mutant DNA fragments detected in plasma that do not originate from tumor, providing additional validation that increased cfDNA levels in early-stage cancer originate from healthy tissue and not from the tumor. The magnitude of the multiplicative increase in cfDNA differs greatly between the cancer types considered, ranging from a ∼1.3-fold increase in lung cancer, to a ∼12-fold increase in patients with liver cancer. To determine the mechanism responsible for the increase in cfDNA levels, we employ an additional dataset that reports the cfDNA composition regarding its tissue of origin, in healthy individuals and patients with pancreatic and ovarian cancer. We find that elevated cfDNA levels in cancer patients do not originate from a proportional increase in cfDNA shedding, but from impaired clearance of cfDNA. The impaired cfDNA clearance could stem either from a direct decrease in cfDNA clearance rate in the presence of cancer, or can be due to a saturation effect in the cfDNA clearance mechanism, triggered by smaller increases in cfDNA shedding due to cancer. Our results contribute to the development of quantitative understanding of cfDNA dynamics in the presence of cancer. Citation Format: Konstantinos Mamis, Ivana Bozic. Quantification of the effect of early-stage cancer on cell-free DNA levels in plasma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 5902.

Comparative analysis of the short-term germination and metal accumulation patterns of two Sorghum hybrids

Metal contamination poses a high risk for organisms, especially those with extensive food chain relevancy. Thus, elevated concentration of metals is considered a major cause for concern in crops. This study aimed to evaluate the short-term responses of sorghum and Sudan grass to different Cd/Zn doses in a complex germination test by assessing growth parameters, tissue metal concentrations, and metal interaction accountant for the ecophysiological and elemental alterations. To do so, radicle and hypocotyl length were measured, and Ca, K, Mg, Cd, Cu, Fe, and Zn concentrations were determined after 24, 72, and 120 h. Our results indicated significant (p < 0.05) differences in the radicle and hypocotyl length by species, contaminant dose, and exposure time. Further, the applied doses along the exposure time gradient significantly and variously affected tissue concentrations. Out of the comparisons involving single metal doses, two significant interactions were revealed: the concentrations of both Cu and Fe were significantly reduced by the increase in Cd concentration in Sudan grass tissues. It was concluded that both species have an excellent potential to indicate metal contamination and accumulate metals in the short term, however, with differences in their responses along the exposure gradient. Additionally, this study filled a literature gap by revealing major patterns and limitations in growth and metal accumulation for sorghum and Sudan grass, thereby supporting further research and practical implications.Graphical

Abstract 2524: Lipid-based nanoparticles for the theranostic treatment of brain tumors using focused ultrasound

Abstract Glioblastoma is an extremely aggressive brain tumor and currently has limited effective treatment options, with a median survival of 14 months. This low survival is partially attributed to the blood-brain barrier (BBB), especially in early-stage glioblastoma. An emerging clinically approved technology to non-invasively and transiently open the BBB is focused ultrasound (FUS) in combination with microbubble cavitation. In this study, we formulated a dual-imageable drug-loaded lipid-based nanoparticle (ActNano) and tested their efficacy against U87-MG in vitro and in vivo (subcutaneous). In addition, we performed focused ultrasound (FUS) induced BBB opening to deliver ActNano into both healthy mice brains and mice bearing orthotopic brain tumors (U87-MG). ActNano uptake was determined and quantified in vivo and ex vivo using MRI and near-infrared fluorescence (NIRF) imaging, respectively. In addition, drug uptake enhancement following FUS BBB opening in orthotopic tumours was also determined using HPLC (SN-38) and ICP MS (carboplatin). ActNano was loaded with SN-38 (1.11 ± 0.08 mg/ml) and carboplatin (0.84 ± 0.14 mg/ml). The ability of ActNano to supress tumor growth was investigated with single treatments against a U87-MG subcutaneous flank xenograft model (10 mg/kg SN-38 &amp; carboplatin). FUS-induced BBB opening was performed in mice (peak-negative pressure = 320 kPa, number of cycles = 500, pulse repetition frequency = 5 Hz, number of pulses = 600). SonoVue microbubbles (2 ml/kg) and ActNano (8 ml/kg, 10 mg/kg SN-38) were administered intravenously during FUS treatment. T1-weighted MRI was performed in a 9.4-T MRI 4 hours after BBB opening, to allow time for ActNano to accumulate in the brain/tumors for optimal T1 contrast. NIRF imaging, H&amp;E staining and drug quantification was performed on perfused and excised brains after the final time point, to confirm successful liposome delivery into the sonicated volume. ActNano was successfully formulated with both MRI and NIRF contrast. ActNano (10 mg/kg SN-38) treatment caused an increase in survival of mice with xenograft tumours when administered alone and a significant increase in survival and tumor uptake when combined with FUS. MRI and NIRF imaging confirmed localized increased uptake of ActNano where FUS-induced BBB opening was performed compared to the contralateral control side. Quantification of Gd, carboplatin and SN-38 confirmed a significant increase in drug concentration in the tumor following BBB opening. These results suggest that MRI/NIRF-tagged drug loaded lipid-nanoparticles are suitable drug carriers for the treatment of glioblastoma in combination with FUS-induced BBB opening. Future work includes evaluation of the survival benefit of ActNano in tumor-bearing mice. Citation Format: Paul Cressey, Chris Payne, Amelia Claxton, Benedetta Arno, Christopher Ireson, Maral Amrahli, David Thurston, Antonios Pouliopoulos, Maya Thanou. Lipid-based nanoparticles for the theranostic treatment of brain tumors using focused ultrasound [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 2524.

The Impact of Light Parameters and Tetracycline Concentration on Antimicrobial Photodynamic InactivationAgainst Drug Resistant Escherichia coli.

ABL is an effective antimicrobial approach and recent studies indicated tetracycline has the ability to produce reactive oxygen species under blue light irradiation. However, the impact of light parameters and tetracycline concentration on the antimicrobial efficacy is not clear. In this study, we investigated the impacts of light dose, drug concentration, and irradiance on drug resistant Escherichia coli survival. The results showed the increase of light dose and drug concentration caused the increase in oxidative damage and bacterial death. Besides, we found the impact of irradiance on the combined antimicrobial effect was affected by the drug concentration. The results of photobleaching and dissolved oxygen showed the different rates of photochemical reaction under different irradiance. Finally, we proposed that suitable light treatment can be designed by varying the tetracycline concentration, light dose, and irradiance for different situations.

Neighboring Carbon Defects Enhanced Molecular Oxygen Activation of Cobalt Single Atom Catalysts Toward Efficient Aerobic Alcohols Oxidation

AbstractThe effective adsorption and activation of molecular oxygen (O2) is crucial for aerobic alcohol oxidation; however, flexibly modulating the electronic structure of catalysts to improve the capability remains challenging. Herein, the concentration of carbon defects surrounding the nitrogen‐coordinated cobalt (Co) single atoms on candle soot is controlled just through adjusting the amount of polyethyleneimine which chemically decorates the surface of candle soot to anchor Co ions. The concentration increase of carbon defects boosts the aerobic alcohol oxidation over the Co single‐atom catalyst as well as ruthenium single‐atom catalyst. Moreover, a series of alcohols, including those with sensitive groups, reach an outstanding yield. Significantly, the calculations and experiments verify that the carbon defects lead to the rearrangement of d‐orbitals of Co atom and an elevation in the spin states of dyz and orbitals. Furthermore, compared with low‐spin Co atom, the stronger electron‐transfer interaction between high‐spin Co atom and O2 enhances the adsorption and activation of O2 and the generation of more superoxide radicals to promote alcohol oxidation. Our findings provide a new way for developing advanced single‐atom catalysts for sustainable aerobic alcohol oxidation via manipulating the spin configurations of single atoms.

Efficacy of Switching to Levetiracetam After S-1-Induced Phenytoin Concentration Increase: A Case Report

Efficacy of Switching to Levetiracetam After S-1-Induced Phenytoin Concentration Increase: A Case Report

Filamentous chemokine CCL5 structure and the functional aspects

Human inflammation-related CC chemokine ligand 5 (hCCL5) has significant self-assembly property under physiological conditions. The mechanism and function of hCCL5 oligomerization remain unclear. Different intermolecular interactions, such as E66-K25 or E66-R44/K45, have been reported to mediate hCCL5 oligomerization. This complexity makes structural determination difficult. Based on a K25S mutation to eliminate the E66-K25 interaction, we observed hCCL5 forming a helical-sharped filament in transmission electron microscopy (TEM). The filamentous polymerization is a dominant process when the concentration reaches ~ 100 nM and the filaments further form a higher-order assembly when concentration increases. In this large filament, a combination of X-ray solution scattering and cryo-EM analysis determined the structure; NMR further confirmed the filament packing, in which the interactions of residues R44 and K45 are critically involved. The sequence 43TRKNR47 was found to be essential for CCL5 trafficking inside the cells and for glycosaminoglycan binding outside the cells. The functional aspects of the chemokine filament are discussed.

The impact of air pollution on the settlement intention of the floating population——Empirical evidence from China

This paper utilizes 2017 dynamic monitoring data of China’s floating population and matches it with air pollution data from 287 prefecture-level cities to construct a Probit model. The study aims to investigate the effects and pathways of air pollution on the settlement intention of floating populations. The research findings are as follows: Firstly, air pollution significantly affects the settlement intention of floating populations, with an increase in air pollution concentration leading to a notable decrease in their intent to reside. Secondly, the impact of air pollution on the settlement intention of floating populations varies based on their personal characteristics and regional features. Those with longer years of residence, higher education levels, and better air quality in their hometowns tend to be more sensitive to air pollution. Thirdly, air pollution reduces the settlement intention of floating populations by affecting their physical health. Further research finds that better healthcare services provided by the government can enhance the willingness of migrant populations to settle in areas with environmental pollution. This study enriches the relevant research on environmental factors’ influence on the settlement intention of floating populations, and it provides insights for the government to formulate talent attraction policies from an environmental governance perspective.

Development of a near-infrared fluorescent probe for in situ monitoring of hydrogen peroxide in plants.

Development of a near-infrared fluorescent probe for in situ monitoring of hydrogen peroxide in plants.