Search

Immuno-photodynamic therapy (IPDT) has emerged as a new modality for cancer treatment. Novel photosensitizers can help achieve the promise inherent in IPDT, namely, the complete eradication of a tumor without recurrence. We report here a small molecule photosensitizer conjugate, LuCXB. This IPDT agent integrates a celecoxib (cyclooxygenase-2 inhibitor) moiety with a near-infrared absorbing lutetium texaphyrin photocatalytic core. In aqueous environments, the two components of LuCXB are self-associated through inferred donor–acceptor interactions. A consequence of this intramolecular association is that upon photoirradiation with 730 nm light, LuCXB produces superoxide radicals (O2–•) via a type I photodynamic pathway; this provides a first line of defense against the tumor while promoting IPDT. For in vivo therapeutic applications, we prepared a CD133-targeting, aptamer-functionalized exosome-based nanophotosensitizer (Ex-apt@LuCXB) designed to target cancer stem cells. Ex-apt@LuCXB was found to display good photosensitivity, acceptable biocompatibility, and robust tumor targetability. Under conditions of photoirradiation, Ex-apt@LuCXB acts to amplify IPDT while exerting a significant antitumor effect in both liver and breast cancer mouse models. The observed therapeutic effects are attributed to a synergistic mechanism that combines antiangiogenesis and photoinduced cancer immunotherapy.

Controllable metal–support interaction (MSI) modulations have long been studied for improving the performance of catalysts supported on metal oxides. However, the corresponding in-depth study for metal1-metal2(M1-M2) composited configurations is rarely achieved due to the lack of reliable models and manipulation mechanisms of MSI modifications. We modeled ruthenium on copper support (Ru–Cu) metal catalysts with negligible interfacial contact potential (e0.06 V) and investigated MSI-dependent hydrogen evolution reaction (HER) catalysis kinetics induced by an electronic hydroxyl (HO-) modifier. Comprehensive simulations and characterizations confirmed that adjusting the HO- coverage can readily realize the tailorable improvement of MSI, facilitating charge migration at the Ru–Cu interface and optimizing the overall HER pathway on active Ru. As a result, a 5/10 monolayer (ML) HO-modified catalyst (5/10 ML) exhibits superior HER activity and durability owing to the relatively stronger MSI. This catalyst also ensured sustainable and efficient hydrogen generation in a urea electrolyzer with significant energy savings. Our work provides a valuable reference for optimizing the MSI-activity relationship in M1-M2catalysts that target more than just HER.

Anode materials for Li-ion batteries have attracted significant research interest owing to the growing demand for efficient and cost-effective energy storage systems. Among the various anode materials being studied, silicon-based anodes have garnered considerable attention as a result of their potential to overcome many of the limitations associated with graphite anodes. However, silicon-based anodes undergo high volumetric expansion during cycling, which results in anode failure. In contrast, silicon-oxide-based (SiOx) materials exhibit limited volumetric expansion, making them viable candidates as anode materials in lithium-ion batteries. Despite this, there remain several challenges associated with SiOxanodes, including volumetric expansion (160–200%), poor capacity retention, and low initial coulombic efficiency. To address these issues, the incorporation of heteroatoms into SiOxanodes has been proposed as a promising strategy. In this review, we aim to provide an overview of the current state of research on SiOxanodes, including experiments and theoretical calculations, with a focus on the insertion of heteroatoms to improve the anode performance. In particular, we examine the effects of heteroatom incorporation on the anode conductivity, lithium diffusion, durability, and initial coulombic efficiency. In addition, we present a design strategy for the insertion of heteroatoms into the SiOxanodes. This review aims to provide a comprehensive understanding of the role of heteroatoms in SiOxanodes and highlight the potential for further research in this area.

In recent years, the graphyne family (GyF), an emerging carbon allotrope, has received increasing attention because of its unique structural and electronic properties. As one member of the GyF, graphyne nanotubes (GyNTs) are considered promising material candidates for various applications. However, the development of GyNTs is still in its early stages, with most studies focusing on zigzag or armchair nanotubes. In this work, a series of GyF-based nanotubes, including graphdiyne nanotubes (GDyNTs) such as γ-GDyNTs and β-GDyNTs, along with δ-GyNTs, β4-GyNTs, T4,4,4-GyNTs, 4,12,2-GyNTs, 4,12,4-GyNTs, and cp-GyNTs, were constructed with (n, 0), (n, n), and chiral (n, m) edges. Density functional tight binding calculations revealed that all γ-GDyNTs, β-GDyNTs, and δ-GyNTs acted as semiconductors with variable dependence on chirality. In contrast, all β4-GyNTs, T4,4,4-GyNTs, 4,12,2-GyNTs, 4,12,4-GyNTs, and cp-GyNTs acted as semimetals with minimal band gaps. This study provides a new approach for producing Gy-/GDy-based conductive devices.

Single-molecule magnetic junctions provide versatile platforms for use in manipulating spin-polarized currents via fine-tuning the electronic properties of the sandwiched molecule. We employed the nonequilibrium Green’s function and spin-polarized density functional theory simulations to investigate the performances of high-spin organic oligoradicals as spin filters sandwiched between two gold electrodes. The spin-polarized current could be obtained using the junction bearing a high-spin molecule with almost unity spin filtering efficiency. Moreover, the spin filtering efficiency could be tuned by varying the number of magnetic units, e.g., di-, tri-, and tetraradicals. Transmission eigenchannel, spin orbital, and density of states analyses revealed how the magnetic exchange interaction in a molecule modulates the dominant electron conducting channels and spin filtering efficiency. The use of a tunable organic magnetic molecular junction system may be a promising approach in manipulating the spin-polarized currents in spintronic devices.

Molecular diameter is an essential molecule-size descriptor that is widely used to understand, e.g., the gas separation preference of a permeable membrane. In this contribution, we have proposed two new molecular diameters calculated respectively by the circumscribed-cylinder method (Dn′) and the group-separated method (Dn), and compared them with the already known kinetic diameter (Dk), averaged diameters (Dpa), and maximum diameters (Dpmand Dmm) in correlating with the penetration barriers of small gas molecules on a total of 14 porous carbon-based monolayer membranes (PCMMs). D1′and D2′give the best barrier–diameter correlations with average Pearson’s correlation coefficients of 0.91 and 0.90, which are markedly larger than those (0.77, 0.76, 0.60, 0.48, 0.33, and 0.32) for D1, D2, Dk, Dpa, Dpm, and Dmm. Our results manifest that the choice of vdW radii set does not drastically change the barrier–diameter correlation. Our newly defined D1′, D2′, D1, and D2, especially D1′and D2′, show universal applicability in predicting the relative permeability of small gas molecules on different PCMMs. The circumscribed-cylinder method proposed here is a facile approach that considers the molecule’s directionality and can be applicable to larger molecules. The excellent linear correlation between Dn′and gas penetration barrier implies that the computationally less demanding molecular diameter Dn′can be an alternative to the penetration barrier in diagnosing the gas separation preference of the PCMMs.

In this study, we investigated the neurobehavioral alterations and modifications of gene expression in the brains of female mice exposed to low-level mercury vapor and/or methylmercury during postnatal development. The mice were exposed to low-level mercury vapor at a mean concentration of 0.094 mg/m3and supplied with tap water containing 5 ppm methylmercury from postnatal day 11 to 12 weeks of age. Behavioral analyses were performed at 17 weeks of age. Total locomotor activity in the open field test and the retention trial performance in the passive avoidance test were significantly reduced in the combined exposure group compared with those in the control group. The differences in locomotor activity and performance in the retention trial at 17 weeks were no longer detected at 45 weeks. These results suggest that the effect of aging on the behavioral abnormalities resulting from postnatal exposure to mercury complexes are not significant. In the microarray analysis of brains in the combined exposure group, the gene expression levels of Ano2and Sgk1were decreased. Real-time RT-PCR analysis confirmed these changes caused by combined mercury exposure, showing significant downregulation of Ano2and Sgk1in the cerebrum. These genes play key roles in the brain as a calcium-activated chloride channel and as a kinase that responds to cellular stress, respectively. Our findings provide insight into the neurobehavioral changes caused by combined mercury exposure.

Transmission of microplastics (MPs) through aerosolization has been recently realized as an important route. Inspite of the reports of the ubiquitous MP presence in aerosols, the spatio-temporal information is inadequate and has very limited practicality in assessing if aerosol can be a significant source of MPs to the marine environment. Data on marine contribution to atmospheric MPs is exceptionally scarce, and the ocean-air exchange is considered an emerging research area. Evidence of MPs entering the oceans via atmospheric deposition has been recently produced. The idea of ocean-air exchange emanates from the fact that beach sediments can get suspended under sand and dust storms, bubble bursts and sea sprays due to wind and waves in surf zones can lead to the ejection of particles into aerosols. In this succinct review, we have tried compiling the data on atmospheric MPs that can shed some light on the flux from and to the aquatic environment. While the information is too limited never the less its incorporation into the marine MP cycle cannot be neglected.

IMPORTANCE: Palmoplantar pustulosis (PPP) has been reported to be accompanied by systemic conditions. However, the risks of comorbidities in patients with PPP have rarely been evaluated. OBJECTIVE: To assess the risks of comorbidities in patients with PPP compared with patients with psoriasis vulgaris or pompholyx. DESIGN, SETTING, AND PARTICIPANTS: This nationwide population-based cross-sectional study used data from the Korean National Health Insurance database and the National Health Screening Program collected from January 1, 2010, to December 31, 2019. Data were analyzed from July 1, 2020, to October 31, 2021. Korean patients diagnosed with PPP, psoriasis vulgaris, or pompholyx who visited a dermatologist between January 1, 2010, and December 31, 2019, were enrolled. EXPOSURES: Presence of PPP. MAIN OUTCOMES AND MEASURES: The risks of comorbidities among patients with PPP vs patients with psoriasis vulgaris or pompholyx were evaluated using a multivariable logistic regression model. RESULTS: A total of 37 399 patients with PPP (mean [SD] age, 48.98 [17.20] years; 51.7% female), 332 279 patients with psoriasis vulgaris (mean [SD] age, 47.29 [18.34] years; 58.7% male), and 365 415 patients with pompholyx (mean [SD] age, 40.92 [17.63] years; 57.4% female) were included in the analyses. Compared with patients with pompholyx, those with PPP had significantly higher risks of developing psoriasis vulgaris (adjusted odds ratio [aOR], 72.96; 95% CI, 68.19-78.05; P < .001), psoriatic arthritis (aOR, 8.06; 95% CI, 6.55-9.92; P < .001), ankylosing spondylitis (aOR, 1.91; 95% CI, 1.61-2.27; P < .001), type 1 diabetes (aOR, 1.33; 95% CI, 1.16-1.52; P < .001), type 2 diabetes (aOR, 1.33; 95% CI, 1.29-1.38; P < .001), Graves disease (aOR, 1.25; 95% CI, 1.11-1.42; P < .001), Crohn disease (aOR, 1.63; 95% CI, 1.11-2.40; P = .01), and vitiligo (aOR, 1.87; 95% CI, 1.65-2.12; P < .001) after adjusting for demographic covariates. The risks of ankylosing spondylitis (aOR, 1.37; 95% CI, 1.16-1.62; P < .001) and Graves disease (aOR, 1.40; 95% CI, 1.23-1.58; P < .001) were significantly higher among patients with PPP vs psoriasis vulgaris. However, the risks of psoriatic arthritis (aOR, 0.54; 95% CI, 0.47-0.63; P < .001), systemic lupus erythematosus (aOR, 0.67; 95% CI, 0.46-0.97; P = .04), Sjögren syndrome (aOR, 0.70; 95% CI, 0.50-0.96; P = .03), systemic sclerosis (aOR, 0.29; 95% CI, 0.11-0.77; P = .01), vitiligo (aOR, 0.53; 95% CI, 0.47-0.60; P < .001), and alopecia areata (aOR, 0.88; 95% CI, 0.81-0.95; P = .001) were significantly lower among those with PPP vs psoriasis vulgaris. CONCLUSIONS AND RELEVANCE: The results of this cross-sectional study suggest that patients with PPP have an overlapping comorbidity profile with patients with psoriasis vulgaris but not patients with pompholyx. However, the risks of comorbidities among patients with PPP may be substantially different from those among patients with psoriasis vulgaris.

We theoretically monitor the photoinduced ππ* → nπ* internal conversion process in 4-thiouracil (4TU), triggered by an optical pump. The element-sensitive spectroscopic signatures are recorded by a resonant X-ray probe tuned to the sulfur, oxygen, or nitrogen K-edge. We employ high-level electronic structure methods optimized for core-excited electronic structure calculation combined with quantum nuclear wavepacket dynamics computed on two relevant nuclear modes, fully accounting for their quantum nature of nuclear motions. We critically discuss the capabilities and limitations of the resonant technique. For sulfur and nitrogen, we document a pre-edge spectral window free from ground-state background and rich with ππ* and nπ* absorption features. The lowest sulfur K-edge shows strong absorption for both ππ* and nπ*. In the lowest nitrogen K-edge window, we resolve a state-specific fingerprint of the ππ* and an approximate timing of the conical intersection via its depletion. A spectral signature of the nπ* transition, not accessible by UV–vis spectroscopy, is identified. The oxygen K-edge is not sensitive to molecular deformations and gives steady transient absorption features without spectral dynamics. The ππ*/nπ* coherence information is masked by more intense contributions from populations. Altogether, element-specific time-resolved resonant X-ray spectroscopy provides a detailed picture of the electronic excited-state dynamics and therefore a sensitive window into the photophysics of thiobases.

AbstractA novel heterozygous mutation, Pro525Arg (P525R) in the Fused in Sarcoma (FUS) protein is predominant in young adult females with familial amyotrophic lateral sclerosis (fALS). Investigation of the biophysical characteristics of this mutation through analysis of protein conformation could provide insights into the pathogenic mechanism of amyotrophic lateral sclerosis (ALS). Here, several computational prediction tools were applied to investigate the effect of P525R on the stability, flexibility, and function of FUS. Conservation and biochemical analyses showed that P525 is highly conserved; the mutation of proline to arginine at position 525 in FUS results in a notable increase in molecular weight, number of hydrogen bonds, and loss of hydrophobicity. By performing electrostatic potential, intra-protein interaction, and binding affinity analyses, we found increased electrostatic potential charge in the mutant protein and fewer hydrophobic interactions than the wild-type structure. Binding affinity of the FUS nuclear localization signal (NLS) mutant for transportin (Trn1) was also decreased compared to wild-type. Our molecular dynamics (MD) simulation results highlighted the exchange between hydrophobic and hydrophilic residues from the core to the surface in the mutant structure; also, upon P525R mutation, FUS became less stable, less flexible and more compact and rigid. Overall, this study demonstrated that the Pro525Arg mutation significantly alters the structure and conformation of FUS through loss of nuclear function, thereby likely contributing to its accumulation in the cytoplasm, which has been implicated in the pathogenesis of fALS. Our study can potentially aid in the design of drugs for FUS-associated neurodegenerative diseases.

The intrinsic origin of amyloid aggregation has been pursued as a new pathogenesis for Alzheimer's disease (AD). The aggregation mechanisms influenced by histidine tautomerism were previously investigated in Aβ40 and Aβ42 monomers. In the present study, we focus on the structural properties of Aβ40 heterodimer under the influence of histidine. The results of molecular dynamics simulation detected different aggregation trends were detected in different heterodimers formed by the εεε isomer and other isomers. In the (εεε:δδδ) dimer, the highest β‐sheet content was obtained in the δδδ chain, which is in agreement with our previous studies that δδδ monomer is the most easily formed β‐sheet secondary structure in the monomer. Further analysis confirmed that (εεε:δδδ) dimers more easily aggregate into fibrils in comparison with other heterodimers. This research will help in understanding the tautomeric effect on Aβ heterodimers, thereby helping to figure out the pathogenesis of AD. Histidine tautomerism is considered to be one of the most important factors of Aβ aggregation. In this regard, we performed molecular dynamics simulations to study the dimerization of Aβ under the histidine tautomerism effect. The present study will help to better understand the histidine tautomeric effect on the early stage of Aβ aggregation, so as to find better treatments for Alzheimer's disease.

Realizing maximum tumor suppression along with preventing tumor regrowth by optimizing the photon usage in phototherapy remains a major challenge. Herein, a mitochondria-targeted phototheranostic nanoformulation (MsPDTT NPs) was prepared from a molecular theranostic encapsulated into phospholipids. Notably, under single 690 nm laser excitation, MsPDTT NPscan perform dual-mode photoacoustic and near-infrared fluorescence imaging and potent photodynamic therapy/photothermal therapy (PDT/PTT) because of efficient excited-state deactivation pathways (through radiative and energy transfer to generate reactive oxygen species and non-radiative relaxation). The reference RsPDTT NPslacking the mitochondria-targeting feature exhibit only the PTT property. Based on biological results, the MsPDTT NPtherapeutic response can be switched to PDT and PTT under normoxic and hypoxic environments and maximize the overall efficacy of phototherapies without any noticeable side effects. The current findings suggest the potential of using simultaneous PDT/PTT with proper photon utilization as a promising theranostic approach for hypoxic tumor photoablation.

Diglycolamides (DGAs) show excellent application prospects for the extraction and separation of rare earth metals from highly radioactive liquid wastes and rare earth ores. The extraction ability of DGAs for rare earth ions in nitrate or chloride media increases with increasing atomic number of the rare earth metal. To understand the origin of this phenomenon, three binuclear crystals [Ln(TEDGA)3][Ln(NO3)6] of N,N,N′,N′-tetraethyldiglycolamide (TEDGA) with rare earth ions La(III), Pr(III) and Eu(III) were prepared and characterized crystallographically. The three complexes belong to the triclinic crystal system, P-1 space group. The bond lengths of Ln–Oamideare significantly shorter than those of Ln–Oetherin the same crystal. The Ln–Oamideand Ln–Oetherbond lengths gradually decrease with increasing atomic number of the rare earth ion. The dihedral angle formed by TEDGA and metal ions through the tridentate coordination gradually increases with increasing metal ion atomic number, tending toward the formation of sizeable planar coordination structures for the most massive rare earth ions. The structures of the compounds formed by the extractant and metal ion were optimized by means of DFT simulations. We find that the interaction between TEDGA and the rare earth ion is dominated by electrostatic interaction by analyzing binding energy, WBIs, Mulliken charge, natural electron configurations, and molecular orbital interaction. The covalent component of the Ln–O bonds of the complexes increases with increasing metal atomic number. The observed increase in extraction and separation capacity of diglycolamides for rare earth ions with increasing atomic number might be due to the formation of two five-member rings by one tridentate ligand. The rare earth ions with large atomic numbers tend to form planar structures with large dihedral angles with DGA ligands.

Transition metal single-atom catalysts (SACs) have been regarded as possible alternatives to platinum-based materials due to their satisfactory performance of the oxygen reduction reaction (ORR). By contrast, main-group metal elements are rarely studied due to their unfavorable surface and electronic states. Herein, a main-group Sn-based SAC with penta-coordinated and asymmetric first-shell ligands is reported as an efficient and robust ORR catalyst. The introduction of the vertical oxygen atom breaks the symmetric charge balance, modulating the binding strength to oxygen intermediates and decreasing the energy barrier for the ORR process. As expected, the prepared Sn SAC exhibits outstanding ORR activity with a high half-wave potential of 0.912 V (vs RHE) and an excellent mass activity of 13.1 A mgSn–1at 0.850 V (vs RHE), which surpasses that of commercial Pt/C and most reported transition-metal-based SACs. Additionally, the reported Sn SAC shows excellent ORR stability due to the strong interaction between Sn sites and the carbon support with oxygen atom as the bridge. The excellent ORR performance of Sn SAC was also proven by both liquid- and solid-state zinc–air battery (ZAB) measurements, indicating its great potential in practical applications.

The intramolecular magnetic coupling constants (J) of 9 diradicals (i–ix) coupled with an aromatic ring were investigated by means of unrestricted density functional theory (DFT) calculations [UB3LYP/6-311++G(d,p)]. For these diradicals, a remarkable linear relationship between the calculated and experimental Jvalues was found. In this study, we suggest that the slope (0.380) of the linear relationship can be utilized as a scaling factor for estimating Jvalues. By applying this scaling factor and calculating Jvalues, we could predict the reliable Jvalues of four dithiadiazolyl (DTDA) diradicals coupled with an aromatic ring. It was also found that this scaling scheme shows a dependence on the length of a coupler. Nevertheless, this scaling approach could be used to estimate Jvalues for diverse diradical systems coupled with a particular coupler by DFT calculations.

Investigation of charge carrier recombination dynamics is central to understanding and further enhancing the photocatalytic activity of water splitting and other photochemical reactions catalyzed by TiO2. In this study, we carried out nonadiabatic molecular dynamics calculations combined with real-time time-dependent density functional theory to investigate the effects of size and shape on charge recombination in TiO2nanoparticles (NPs). Using the Wulff construction method, we considered both octahedral (10, 35, and 84 TiO2units) and cuboctahedral (29, 78, and 97 TiO2units) nanoclusters with size varying from 1 to 3 nm. Generally, the recombination rates decreased with increasing NP size. We rationalized the trend in terms of average transition energy, exciton binding energy (ΔEex), nonadiabatic coupling (NAC), and pure-dephasing time. The relaxation times increased with increasing NP size, as the NAC and ΔEexdecreased. The cuboctahedral clusters showed smaller ΔEexcompared to the octahedral clusters. For the octahedral clusters, the smaller NAC and shorter dephasing time contributed to longer relaxation, despite smaller transition energy, as the size increased. However, the influence of the NAC, transition energy, and dephasing time were intertwined for the cuboctahedral clusters. The smaller NAC of the 97-unit cluster rationalized its longer relaxation time compared to the 29-unit cluster, but the presence of a singly coordinated oxygen atom greatly reduced the transition energy, thus leading to a shorter relaxation time compared to the 78-unit cluster. Our results provide a detailed understanding on the effects of size and shape on the charge carrier dynamics in TiO2nanoclusters, separating these effects from other factors, such as presence of defects, dopants, and adsorbates that are hard to control precisely in experiments.

The self-assembly powder (SAP) with varying Nafion content was synthesized and characterized by XRD, XPS, HRTEM, and mapping. It is observed that the oxygen from oxygen functional groups transfers to the surface of Pt and generate PtO during the process of self-assembly with the mechanism of micro galvanic cell, where Pt, carbon black, and Nafion act as the anode, cathode and electrolyte, respectively. The appearance of PtO on the surface of Pt leads to a turnover of Nafion structure, and therefore more hydrophilic sulfonic groups directly contact with Pt, and thus the triple-phase boundary (TPB) has been expanded.

Density functional theory (DFT) calculations were performed using a MPWB1K functional to interpret the charge transport (CT) properties of stacked annelated β-trithiophene molecules. The goal was to help understand how the chemical composition, face-to-face stacking, intra- and intermolecular correlations, and the applied electric field affect the CT properties of this organic semiconductor compared with those of the edge-to-face “herringbone” motif. The variations in the frontier molecular orbitals, energy gap, nonadiabatic electron attachment energies (EAE), and vertical detachment energies (VDE) were investigated under an external electric field as a function of the number of stacked layers (n). Two possible CT pathways, monomer-to-monomer (MM) and dimer-to-dimer (DD) transports, were postulated to determine the charge carrier conductivities of these molecules. The results highlight that the intermolecular electronic couplings and electrostatic interactions can significantly affect the stacking geometry, even in more extended structures; displaced stacks with smaller interlayer spacing resulted in more compact stacking and, thus, higher CT efficiency; face-to-face stacking geometries can help to reduce the energy gap and VDE. Despite the fact that common thiophene-based oligomers adopting edge-to-face herringbone motifs exhibited p-type (hole-transporting) characters, the face-to-face stacked models based on annelated β-trithiophenes exhibited remarkably increased n-type (electron-transporting) performances. The electric field in the z-direction produced a small influence on the DD charge transport, whereas both electron and hole mobilities decreased dramatically in the MM case. More importantly, in MM charge transport, the electric field increases the hole mobility so that it is higher than that of the electron.

ABSTRACTRecently, the use of plastics has become more widespread due to the vital role they play in daily life and human health. Plastic decomposes into microplastic (MP) in the soil. Owing to the negative consequences of soil MPs’ growth on both soil and human health, several studies conducted over the past 10 years have concentrated on identifying and tracking the origins of MPs in soil. These studies have demonstrated that soil MPs originate from a range of sources, including plastic films, fertilizers, runoff, sewage sludge, irrigation, and the atmosphere. Despite the efforts made to identify specific sources of soil MPs, a thorough analysis and comparison of the primary sources is still absent. By assembling the results of earlier research that demonstrate how irrigation, the atmosphere, and sewage sludge all contribute to the richness of soil MP, this review will aid in filling this knowledge gap. The MP abundance from each of these sources was compared using an analysis of variance (ANOVA). The results of this investigation showed that plastic films are the largest and most significant contributors to soil microplastic contamination, owing to human overdependence on plastic films . Air deposition is the least common source of MPs . The amount of MP did not differ noticeably across irrigation, runoff, sewage sludge, and plastic film. This is because no nterference occurs when MPs from these sources interact with the soil. The findings of this study will be useful for choosing effective management and control techniques for sources of soil MP.

Background: The COVID-19 pandemic has caused delays and restrictions in providing medical services. In response to the medical surge, countries with social insurance systems provided financial incentives to medical institutions. This study aimed to present the directions for health insurance support by comparing countries in terms of the domains and contents of COVID-19 health insurance support to ensure timely support in case of future pandemics. Methods: An analysis framework was developed to compare health insurance policy interventions for COVID-19 and non-COVID-19 domains, and detailed policy interventions were divided into sub-domains (space, staff, and stuff) for each domain. Data were collected by country from the websites of the Ministry of Health and Social Insurers, Organisation for Economic Co-operation and Development, and European Observatory on Health Systems and Policies and were analyzed using qualitative comparative analysis. Results: The countries provided comprehensive support for both the COVID-19 and non-COVID-19 domains. In the COVID-19 domain, overall support was provided in all three sub-domains. Additional cost support was provided to prevent infection and provide secure facilities to treat confirmed patients. Outpatient services were mainly supported, and an intensive intervention was developed in the staff sub-domain for the non-COVID-19 domain. The point of policy intervention was the surge of the first confirmed case. Continuous revisions were subsequently made. The government provided financial support through health insurance. Conclusions: Regarding where policy support through health insurance should be focused, the workload of medical personnel increased according to the change in the service provision environment due to the pandemic, and the medical service delivery system changed to prevent further infection. Consequently, incentives should be provided to aid the provision of stable services to patients and should be an auxiliary means to implement the national quarantine policy more effectively via a health insurance response system that promptly provides additional financial support in case of future crises.

To study the effect of a stable radical on the photophysical properties of a phosphorescent Pt(II) coordination framework and the intramolecular magnetic interaction between radical ligands in the N^N Pt(II) bisacetylide complexes, we prepared a series of N^N Pt(II) bis(acetylide) complexes with oxoverdazyl radical acetylide ligands. The linker between the Pt(II) center and the spin carrier was systematically varied, to probe the effect on the sign and magnitude of the spin exchange interactions between the radical ligands and photophysical properties. The complexes were studied with steady-state and femtosecond/nanosecond transient absorption spectroscopy, continuous-wave electron paramagnetic resonance (EPR) spectroscopy, and density functional theory (DFT) computations. The transient absorption spectral studies show that the doublet excited state of the radicals are short-lived (τD≈ 2 ps) and nonfluorescent. Moreover, the intrinsic long-lived triplet excited state (τT= 1.2 μs) of the Pt(II) coordination center was efficiently quenched by the radical (τT= 6.9 ps for one representative radical Pt(II) complex). The intramolecular magnetic interaction between the radical ligands through the diamagnetic Pt(II) atom was studied with temperature-dependent EPR spectroscopy; antiferromagnetic exchange interaction (−JS1S2, J= −5.4 ± 0.1 cm–1) for the complex with the shortest radical–radical distance through bridge fragments was observed. DFT computations give similar results for the sign and magnitude of the Jvalues. For complexes with larger inter-radical distance, however, very weak coupling between the radical ligands was observed (|J| < 0.7 cm–1). Our results are useful for the study of the effect of a radical on the photophysical properties of the phosphorescent transition-metal complexes.

Histidine state (protonated or δor εtautomer) has been considered the origin of abnormal misfolding and aggregation of β-amyloid (Aβ). Our previous studies reported that the δδδisomer of Aβ(1–40) has a greater propensity for β-sheet conformation compared to other isomers. However, direct proof of the tautomeric effect has not been reported. In this context, we calculated histidine site-specific two-dimensional infrared spectroscopy of the δδδ, εεε, and πππ(all protonated histidine) systems within the framework of classical molecular dynamics simulations aiming at connecting our previous results with the current experimental observations. Our results showed that β-sheet formation is favored for the δδδand πππtautomers compared with the εεεtautomer, consistent with our previous studies. This result was further supported by contact map analyses and the strength of dipole coupling between the amide-I bonds of each residue. The two-dimensional infrared diagonal trace for each tautomer included three distinctive spectrally resolvable peaks near 1680, 1686, and 1693 cm−1, as was also observed for histidine dipeptides. However, the peak positions at His6, His13, and His14 did not show a consensus trend with the histidine or protonation state but were instead affected by the presence of surrounding hydrogen bonds. Our study provides a deeper insight into the influence of tautomerism and protonation of histidine residues in Aβ(1–40) on amyloid misfolding and provides a connection between our previous simulations and experimental observations.

The self-assembly of amyloid-β (Aβ) peptides into senile plaques in the brain is a hallmark of Alzheimer’s disease (AD) pathology. Mutation and histidine tautomerism are considered intrinsic origins in the accumulation of Aβ. As a first step toward understanding the impact of A2V mutation and histidine tautomerism on the Aβ42 isoform, we performed replica-exchange molecular dynamics (REMD) simulations to investigate the effects of histidine tautomerism on the structural properties of A2V Aβ42 peptides. There are generally more β-sheet and less α-helix secondary structures in A2V Aβ42 monomers than in WT Aβ42, implying a higher aggregation tendency in A2V Aβ42, which is consistent with previous studies. The current research will help develop the histidine tautomerism hypothesis of misfolded protein aggregation and eventually elucidate the pathogenesis of AD.

• A temperature-responsive attractive nanoemulsion (ANE) system is proposed. • Drop-to-drop association was obtained by polymer chain conformation-driven dipolar interaction across different oil droplets. • ANEs showed reversible sol–gel transition in response to the temperature change at upper and lower LCST. This study introduces a temperature-responsive attractive nanoemulsion (ANE) system, which is characterized by the polymer chain conformation-driven dipolar interaction across different oil droplets in an aqueous medium. To achieve this, highly stable ANEs were produced by co-assembly of amphiphilic triblock copolymers (ATCs), poly(ethylene oxide)- b -poly(ε -caprolactone)- b -poly(ethylene oxide) (PEO- b -PCL- b -PEO), with lecithin at the oil-water interface. The dipolar attraction of the methoxy terminated-PEO (mPEO) of ATCs on one drop surface with the lecithin head located on the other drop surface led to the drop-to-drop association. We showed that the efficiency of this interdrop association was dominantly influenced by the chain conformation of mPEO blocks. From dense suspension rheology studies, it was demonstrated that the ANEs formed a gel-like phase below the lower critical solution temperature (LCST) of the mPEO, but transformed to a liquid-like phase above the LCST, which occurred reversibly, thus enabling the development of temperature-responsive emulsion fluids. [ABSTRACT FROM AUTHOR]