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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.

A particular variation in the gene for insulin-like growth factor-1 causes increases in insulin-like growth factor-1 and increased bone density, according to a study of 300 women. This gene is apparently one of the genes that regulates bone mass.

Hormone therapy causes a decrease in blood levels of insulin-like growth factor I and proteins that bind to insulin-like growth factor I, but only in women who respond to the therapy. However, these changes do not affect bone density.

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.

Byline: Jung Gu Kim, Jin Yong Lee Keywords: Insulin-like growth factor binding protein; osteoporosis; natural postmenopause Abstract: OBJECTIVE: The objective of this study was to evaluate the relationship between serum insulin-like growth factor binding protein profiles and bone mineral density measurements and biochemical markers of bone turnover in postmenopausal women. STUDY DESIGN: Sera from 37 normal healthy postmenopausal women and 14 postmenopausal women with osteoporosis were analyzed for insulin-like growth factor binding proteins and osteocalcin by Western ligand blotting and radioimmunoassay, respectively. Bone mineral density measurements were performed by dual-energy x-ray absorptiometry. Urinary calcium and creatinine excretion were also determined. The data were analyzed statistically by analysis of variance and the least-squares method. RESULTS: The serum insulin-like growth factor binding protein-2 ratio (Insulin-like growth factor binding protein-2 intensity/total insulin-like growth factor binding protein intensity) in postmenopausal women with osteoporosis was significantly higher (p < 0.02) than that in normal healthy postmenopausal women, but the serum insulin-like growth factor binding protein-3 ratio in women with osteoporosis was significantly lower (p < 0.01). The serum insulin-like growth factor binding protein-2 ratio correlated negatively with the bone mineral density of the lumbar spine (p < 0.0001), femoral neck (p < 0.05), trochanter (p < 0.01), and Ward's triangle (p < 0.05), but there was a significant positive correlation between the serum insulin-like growth factor binding protein-3 ratio and the bone mineral density of the lumbar spine (p < 0.001) and trochanter (p < 0.05). No correlations between serum insulin-like growth factor binding protein levels or serum ratios and biochemical markers of bone turnover were noted. CONCLUSION: The measurement of serum insulin-like growth factor binding protein profiles might be useful in identifying postmenopausal women at risk for osteoporosis. (AM J OBSTET GYNECOL 1996;174:1511-7.) Author Affiliation: Seoul, Korea Article History: Received 6 March 1995; Revised 30 August 1995; Accepted 13 October 1995 Article Note: (footnote) [star] From the Department of Obstetrics and Gynecology, College of Medicine, Seoul National University., [star][star] Supported by grant No. 06-93-003 from the Research Fund of Seoul National University, College of Medicine., a Reprint requests: Jung Gu Kim, MD, PhD., Department of Obstetrics and Gynecology, Seoul National University Hospital, 28 Yeungun-dong Chongno-Ku, Seoul 110-744, Korea., aa 0002-9378/96 $5.00 + 0 6/1/69797

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.

The recent advances in platinum-free and/or metal-free electrocatalysts for electrochemical redox reactions at the electrodes of fuel cells in particular and, broadly speaking, energy devices were thoroughly reviewed. This comprehensive review focuses on nonplatinum precious metal (Pt-free) and/or nonprecious metal (metal-free) electrocatalysts regarding the electrochemical redox reactions at the electrodes of the energy devices. The recent development of electrocatalysts governing the electrochemical redox reaction mechanisms at the electrodes of the fuel cells/energy devices using density functional theory (DFT) methods was overviewed. The understanding of the following were overviewed theoretically in detail: the site of intermediates (oxygen, hydrogen, water, hydrogen peroxide, etc.); adsorption electrocatalysis via oxygen reduction reaction (ORR), oxygen evolution reaction (OER), hydrogen evolution reaction (HER), as well as bifunctional electrocatalysis such as ORR/OER and OER/HER; trifunctional electrocatalysis (ORR, OER, HER); and multifunction catalysis. The critical issues, challenges, and perspectives on the further development of less-expensive and highly efficient (active and stable) electrocatalysts were provided.

Nanodevices based on two-dimensional materials hold great promise for DNA sequencing. Owing to some unique properties, silicene has become a potential alternative to the well-known graphene as a sequencing material. Recently, the recognition of DNA methylation has garnered great attention, since methylated nucleobases are indicated as biomarkers of various forms of cancers. In this work, we investigated the interactions of eight nucleobases (adenine, guanine, thymine, cytosine, 5-methylcytosine, 5-hydroxymethylcytosine, 5-formylcytosine, and 5-carboxylcytosine) with a zigzag silicene nanoribbon. The stabilities of adsorption geometries and electronic properties of nucleobases attached on a silicene nanoribbon surface were examined using density functional theory (DFT) with a van der Waals dispersion correction. The results reveal that adenine is physisorbed on the surface of the silicene nanoribbon, while the other seven nucleobases are weakly chemisorbed. Moreover, the charge transport properties of nucleobase–silicene complexes were analyzed by DFT combined with the nonequilibrium Green’s function. The adsorption effects of the different nucleobases on the charge transport properties of silicene nanoribbon were clarified by the transmission spectra and density of states. According to the obtained current–voltage characteristics, one electrical detection strategy for methylation and DNA sequencing was proposed. We deduced that it is possible to differentiate between all eight nucleobases using electrical signals at distinct applied bias voltages of 0.5 and 1.0 V. Our results indicate that silicene can serve as a potential candidate for exploring methylation discrimination in addition to DNA sequencing.

Two-dimensional van der Waals (vdW) heterojunctions have been regarded as promising candidates for photocatalytic water splitting and solar energy conversion. Here, we propose a two-dimensional GeC/GaN vdW heterostructure, where the GaN monolayer and the GeC monolayer are stacked. The binding energy, phonon spectrum, and elastic constants demonstrate this material’s high dynamic and mechanical stability. Most notably, the GWband structure, GW+ Bethe–Salpeter equation (BSE) optical absorption spectrum, and the band alignment of the density functional theory (DFT) scheme and empirical formula reveal that the GeC/GaN vdW heterostructures have a dramatically high optical absorption coefficient (∼105cm–1) in the visible region and a suitable band edge with sufficiently large kinetic overpotentials of the hydrogen evolution reaction (ΔEc≥ 1.945 eV) and the oxygen evolution reaction (ΔEv≥ 1.244 eV). Photogenerated electrons and holes aggregate on the GeC monolayer and GaN monolayer surfaces, respectively, which could make this heterojunction a promising candidate for photocatalytic water splitting and solar energy conversion.

Third order polarizability, (γ) taken from the collective electronic oscillator (CEO) method was used to calculate the two‐photon absorption (TPA) of tetrastyryl‐[2,2]paracyclophane derivatives with different through‐space charge transfer configurations considering various donor and acceptor combinations at the terminal styryl groups. For the virtually same linear absorption, different TPA spectra were obtained. For controlling and fine‐tuning frequency and cross‐sections of TPA the through‐space charge transfer interactions can be used. The results are explained by the electronic density matrices corresponding to governing oscillators in one‐ and two‐photon absorption and the ground state. It is indicated that for the studied systems mainly the lowest four oscillators are responsible for the TPA cross‐sections rather than a simple effective three‐state model. Two‐photon absorption of paracyclophanes.

Trihydride molecular nanowire (ScH3) is a nonmagnetic semiconductor with a direct band gap and could retain its structure at temperatures up to 1200 K. In this paper, we report that ScH3could be a new type of ideal room-temperature spintronic material. The simulations of the ScH3field-effect transistor show that ScH3turns into a ferromagnetic (FM) half-metal upon electron- or hole-doping induced by the applied gate voltage. State-of-the-art ab initio calculations reveal that the FM of electron-doped ScH3originates from the 3d electrons of Sc atoms, whereas the FM of hole-doped ScH3originates from the 1s electrons of H atoms, which can be understood by the Stoner picture of band magnetism. The spin-polarized quantum molecular dynamics simulations demonstrate that the ferromagnetic half-metal survives at room temperature. These findings reveal that ScH3is a new type of ideal room-temperature spintronic material and opens a new door for finding spintronic materials compatible with the current technology in the semiconductor industry.

The susceptibility of a water molecule to electric fields provides fundamental and essential information for understanding the vibrational spectra of water clusters and condensed-phase water. In this study, the Stark sensitivities for the ν2bending and ν1symmetric stretching vibrations of water molecule were experimentally determined. The water molecules isolated in the solid Ar matrix were spatially oriented in the direction of the externally applied field (∼108V m–1) in the laboratory frame by using the ice-film nanocapacitor method. The signature of the field-induced reorientation of water molecules was observed with reflection–absorption infrared spectroscopy. The Stark sensitivities of the D2O vibrations were determined from the field-induced change of vibrational frequencies of the spatially oriented D2O molecules. The Stark sensitivity of the D2O bending vibration was much larger than that of the symmetric stretching vibration, and the two normal modes showed the opposite signs. Isotope dependence of the Stark sensitivity of the bending vibration was also observed by investigating HDO and H2O molecules. An ab initio calculation was conducted to elaborate on the observed characteristics of the Stark sensitivity of water vibrations.

Previous epidemiologic studies of the natural course of urticaria mainly focused on chronic spontaneous urticaria and were conducted at hospitals. The natural course of new-onset urticaria in the general population is unknown.

Polyphosphate (polyP) is a food additive with antimicrobial activity. Here we evaluated the effects of sodium tripolyphosphate (polyP3, Na5P3O10) on four major oral bacterial species, in both single- and mixed-culture. PolyP3 inhibited three opportunistic pathogenic species: Fusobacterium nucleatum, Prevotella intermedia, and Porphyromonas gingivalis. On the contrary, a commensal bacterium Streptococcus gordoniiwas relatively less susceptible to polyP3 than the pathogens. When all bacterial species were co-cultured, polyP3 (= 0.09%) significantly reduced their total growth and biofilm formation, among which the three pathogenic bacteria were selectively inhibited. Collectively, polyP3 may be an alternative antibacterial agent to control oral pathogenic bacteria.

A new family of all‐carbon structures is proposed via substituting the sp2carbon atom in graphene and graphyne with carbon trigons. Owing to the existence of carbon trigons, these porous carbon allotropes are named as trigraphene and trigraphyne. The calculations of geometrical, vibrational, and energetic properties by density functional theory reveal that all these structures are metastable and dynamically stable. It is further disclosed from the electronic band structures that trigraphene and α‐trigraphyne are metal, while β‐trigraphyne and γ‐trigraphyne are semiconductor with indirect band gaps of 0.33 and 0.52 eV, respectively. Our results suggest a strategy to design new carbon materials with desired properties, and these all‐carbon materials would have many interesting applications once obtained.

Host molecules with a cavity or scaffold with a limited space have been utilized for photodimerization of trans‐stilbene dimer with [2 + 2] cycloaddition. The degrees of freedom of the molecules inside the cavity are generally constrained. The cycloaddition reaction of trans‐stilbene dimer was investigated for variously constrained with inter‐stilbene distances and torsional angles by ab‐initiocalculations at MP2/6‐31G* level of theory. In a very short inter‐stilbene distance, a new multicyclic compound (P1) was obtained, while [2 + 2] cycloaddition product (P2) was obtained from a wide range of geometries. Both inter‐stilbene distance and torsional angle play a pivotal role in determining which product (P1or P2) could be obtained from the cycloaddition reaction of trans‐stilbene dimer.

According to prior studies, it is possible to consider the emergency care utilization due to ambulatory care sensitive conditions (ACSCs) as a proxy measure of access to primary care but there was no confirmed study among people with disabilities.

Electrocatalytic nitrate reduction using renewable energy is a potential approach to environmental remediation and ammonia production, yet it is hindered by sluggish kinetics and poor efficiency. Herein, a well-defined carbon nanosheet array-supported cobalt phosphide (CoP; CNs@CoP) electrocatalyst is synthesized, achieving remarkable performance for nitrate reduction to ammonia with a Faraday efficiency of 95.1% at −0.30 V vs. reversible hydrogen electrode (RHE) and a yield rate of 43.9 mg h−1cm−2at −1.0 V vs. RHE. Moreover, an electrocatalytic nitrate reduction coupled with glycerol oxidation system is constructed, which delivers dramatically enhanced ammonia production (15.2 mg h−1cm−2) and gains high value-added formate (111.4 mg h−1cm−2) at 1.8 V cell voltage. Preliminary technoeconomic analysis confirms the economic feasibility of the coupled system. We also design a new CO2capture strategy by using as-prepared ammonia as absorbent, which is promising for sustainable ammonia synthesis and its application.

Microplastic (MP) contamination has become a pervasive global issue, affecting terrestrial and aquatic environments, and its potential health hazards are of widespread concern. This review examined the intricate relationship between animal exposure to MPs and their health effects, revealing that MP contamination affects a broad spectrum of animal species across terrestrial and aquatic habitats. Crucially, interspecies differences in ingestion, accumulation, and responses to MPs emerge as central themes arising from various factors, including feeding behavior, physiology, and ecological niches. The health implications of MP exposure are multifarious; animals may suffer physical harm, endure chemical exposure to adsorbed contaminants, provoke inflammatory responses, and undergo behavioral modifications. Chronic exposure to MPs raises concerns about their long-term health consequences, and the ability of MPs to adsorb and transport chemicals has implications for the bioaccumulation of pollutants within food webs. The ecological ramifications of MP contamination are profound, impacting animal behavior, population dynamics, and ecosystem processes. The intricate interplay between animals and MPs underscores the need for interdisciplinary research that unites fields such as biology, ecology, chemistry, and toxicology. Recognizing the relationship between animal exposure to MPs and their health effects has significant implications, particularly as the potential for MPs to enter the human food chain through animals underscores the need for research on human health risks.

We herein propose a polymeric nanovehicle system that has the ability to remarkably improve cellular uptake and transdermal delivery. Cell-penetrating peptide-patchy deformable polymeric nanovehicles were fabricated by tailored coassembly of amphiphilic poly(ethylene oxide)-block-poly(ε-caprolactone) (PEO-b-PCL), mannosylerythritol lipid (MEL), and YGRKKRRQRRR-cysteamine (TAT)-linked MEL. Using X-ray diffraction, differential scanning calorimetry, and nuclear magnetic resonance analyses, we revealed that the incorporation of MEL having an asymmetric alkyl chain configuration was responsible for the deformable phase property of the vehicles. We also discovered that the nanovehicles were mutually attracted, exhibiting a gel-like fluid characteristic due to the dipole–dipole interaction between the hydroxyl group of MEL and the methoxy group of PEO-b-PCL. Coassembly of TAT-linked MEL with the deformable nanovehicles significantly enhanced cellular uptake due to macropinocytosis and caveolae-/lipid raft-mediated endocytosis. Furthermore, the in vivoskin penetration test revealed that our TAT-patchy deformable nanovehicles remarkably improved transdermal delivery efficiency.

In spite of the importance of vibrational Stark effect (VSE) and many attempts, origin of VSE is still unclear in molecular level. Here, we studied on origin of VSE of hydroxyl stretching vibration in small water clusters (monomer, dimer, and tetramer) assuming that VSE can be separated by nuclear and electronic contribution. We calculated total Stark tuning rate (Δμtot) and its nuclear contribution (Δμgeom) using the ab initio method, then the electronic contribution (Δμelec) was simply obtained by the difference, Δμtot– Δμgeom. In all cases, the nuclear contribution has dominant contribution to VSE. The hydroxyl stretching mode with neighboring hydrogen acceptor showed larger Δμgeomthan that of dangling bonds. Furthermore, the calculated Δμgeombecame larger in larger cluster due to the hydrogen bond network. The comparison between Stark tuning rates including and excluding anharmonicity supports the importance of potential anharmonicity in VSE, as previously reported. Interestingly, a good linear relationship is observed between the hydroxyl stretch frequency (νgeom) and hydroxyl bond length and also between the Stark tuning rate (Δμgeom) and the change of hydroxyl bond length. Similarly, the electronic contribution of calculated frequencies and Stark tuning rate (Δμelec) showed a good linear relationship with atomic charge derived by electronic perturbation (Δqelec) and change of that (Δ(Δqelec)), respectively.

Luteolin (3′,4′,5,7-tetrahydroxyflavone), a type of flavonoid found in medicinal herbs and vegetables, has been of great interest due to its antioxidative, anti-inflammatory, and anticarcinogenic effects. Despite these beneficial biological properties, the ease with which luteolin forms molecular crystals in conventional aqueous formulations has hampered much wider applications. In this study, we introduce an oil-in-water (O/W) nanoemulsion vehicle system for enhanced follicular delivery of luteolin. The luteolin-loaded nanoemulsion, which had an average hydrodynamic size of approximately 290 nm, was produced by the assembly of poly(ethylene oxide)-block-poly(ε-caprolactone) and lecithin at the O/W interface. The luteolin-loaded nanoemulsion showed outstanding stability against drop coalescence and aggregation. This was confirmed from the slight drop size increase after repeated freeze–thaw cycling and long-term storage. Moreover, in vivo hair growth evaluation demonstrated that the luteolin-loaded nanoemulsions fabricated in this study possessed the hair growth-promotion activity, which is comparable with the case of using a luteolin solution in an organic solvent.

Removal of bacterial biofilm from the root canal system is essential for the management of endodontic disease. Here we evaluated the antibacterial effect of N-acetylcysteine (NAC), a potent antioxidant and mucolytic agent, against mature multispecies endodontic biofilms consisting of Actinomyces naeslundii, Lactobacillus salivarius, Streptococcus mutansand Enterococcus faecalison sterile human dentin blocks. The biofilms were exposed to NAC (25, 50 and 100mg/mL), saturated calcium hydroxide or 2% chlorhexidine solution for 7 days, then examined by scanning electron microscopy. The biofilm viability was measured by viable cell counts and ATP-bioluminescence assay. NAC showed greater efficacy in biofilm cell removal and killing than the other root canal medicaments. Furthermore, 100mg/mL NAC disrupted the mature multispecies endodontic biofilms completely. These results demonstrate the potential use of NAC in root canal treatment.

With the advancement of intense ultrafast X-ray sources, it is now possible to create a molecular movie by following the electronic dynamics in real time and real space through time-resolved X-ray diffraction. Here we employ real-time time-dependent density functional theory (RT-TDDFT) to simulate the electronic dynamics after an impulse core or valence ionization in the glycine–phenylalanine (GF) dipeptide. The time-evolving dipole moment, the charge density, and the time-resolved X-ray diffraction signals are calculated. The charge oscillation is calculated for 7 fs for valence ionization and 500 as for core ionization. The charge oscillation time scale is comparable to that found in a phenylalanine monomer (4 fs) [Science2014, 346, 336] and is slightly longer because of the elongated glycine chain. Following valence ionization, the charge migration across the GF is mediated by the delocalized lone-pair orbitals of oxygen and nitrogen of the electron-rich amide group. The temporal Fourier transform of the dipole moment provides detailed information on the charge migration dynamics and the molecular orbitals involved. Heterodyne-detected attosecond X-ray diffraction signals provide the magnitude and phase of the scattering amplitude in momentum space and can thus be inverted to yield the charge density in real space.

This study assessed the interactive changes to the endocrine disruptor 17 alpha-ethynylestradiol (EE2) triggered by photoaging onto fibrous microplastics frequently found in the environment. The physicochemical property change of the polyethylene (PE) microfiber according to irradiation (i.e. 14 d UV-C (254 nm)) was studied through Fourier transform infrared spectroscopy, scanning electron microscope, and contact angle analysis. Additionally, the EE2 adsorption kinetics experiment was performed for the PE microfiber before and after UV irradiation to assess the change in adsorption characteristics. After UV irradiation, the PE microfiber surface roughness increased, the oxygen-containing functional group (e.g. carbonyl group) increased, and the contact angle (virgin PE: 80.02°, aged PE: 65.13°) decreased. A decrease in the surface hydrophobicity led to a decrease in the adsorption rate of EE2 (virgin PE: k= 0.0105 h−1, aged PE: not calculated). The hydrophobic interaction significantly affects the adsorption behavior of hydrophobic organic pollutants such as EE2 onto MPs, and continuous photo-aging of MPs may cause a new pattern of ecological risk. Therefore, there is a greater necessity for additional research relevant to this issue.

All electron relativistic density functional theory (DFT) based calculations using numerical atom-centered orbitals have been carried out to explore the relative stability, atomic, and electronic structure of a series of stoichiometric TiO2anatase nanoparticles explicitly containing up to 1365 atoms as a function of size and morphology. The nanoparticles under scrutiny exhibit octahedral or truncated octahedral structures and span the 1–6 nm diameter size range. Initial structures were obtained using the Wulff construction, thus exhibiting the most stable (101) and (001) anatase surfaces. Final structures were obtained from geometry optimization with full relaxation of all structural parameters using both generalized gradient approximation (GGA) and hybrid density functionals. Results show that, for nanoparticles of a similar size, octahedral and truncated octahedral morphologies have comparable energetic stabilities. The electronic structure properties exhibit a clear trend converging to the bulk values as the size of the nanoparticles increases but with a marked influence of the density functional employed. Our results suggest that electronic structure properties, and hence reactivity, for the largest anatase nanoparticles considered in this study will be similar to those exhibited by even larger mesoscale particles or by bulk systems. Finally, we present compelling evidence that anatase nanoparticles become effectively bulklike when reaching a size of ∼20 nm diameter.

Among the layered transition metal dichalcogenides (TMDs) that can form stable two-dimensional crystal structures, molybdenum disulfide (MoS2) has been intensively investigated because of its unique properties in various electronic and optoelectronic applications with different band gap energies from 1.29 to 1.9 eV as the number of layers decreases. To control the MoS2layers, atomic layer etching (ALE) (which is a cyclic etching consisting of a radical-adsorption step such as Cl adsorption and a reacted-compound-desorption step via a low-energy Ar+-ion exposure) can be a highly effective technique to avoid inducing damage and contamination that occur during the reactive steps. Whereas graphene is composed of one-atom-thick layers, MoS2is composed of three-atom-thick S(top)Mo(mid)S(bottom)layers; therefore, the ALE mechanisms of the two structures are significantly different. In this study, for MoS2ALE, the Cl radical is used as the adsorption species and a low-energy Ar+ion is used as the desorption species. A MoS2ALE mechanism (by which the S(top), Mo(mid), and S(bottom)atoms are sequentially removed from the MoS2crystal structure due to the trapped Cl atoms between the S(top)layer and the Mo(mid)layer) is reported according to the results of an experiment and a simulation. In addition, the ALE technique shows that a monolayer MoS2field effect transistor (FET) fabricated after one cycle of ALE is undamaged and exhibits electrical characteristics similar to those of a pristine monolayer MoS2FET. This technique is also applicable to all layered TMD materials, such as tungsten disulfide (WS2), molybdenum diselenide (MoSe2), and tungsten diselenide (WSe2).

Highly ordered mesoporous CdxZn1–xS materials were obtained via a simple nanoreplication method using a mesoporous silica template with a 3-D bicontinuous cubic Ia3d mesostructure. Combined analyses using X-ray diffraction, N2sorption, electron microscopy, and diffuse reflectance UV–visible spectroscopy revealed that the ordered mesoporous ternary compound semiconductor materials exhibited well-developed crystalline frameworks, high surface areas of 80–120 m2g–1, uniform mesopore sizes of about 20 nm, ordered arrangement of mesopores, and outstanding visible light absorption properties. Photocatalytic activities were investigated by degradation of methylene blue and rhodamine B under visible light over the mesoporous CdxZn1–xS materials. Due to the high surface area and outstanding light absorption properties, the ordered mesoporous CdxZn1–xS exhibited excellent photocatalytic performances for the degradation of methylene blue and rhodamine B. This study indicates a potential application of the mesoporous compound semiconductors in the efficient visible-light-driven photolysis of organics that may cause environmental pollution.