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Protein S-acylation is an important post-translational modification in eukaryotes, regulating the subcellular localization, trafficking, stability, and activity of substrate proteins. The dynamic regulation of this reversible modification is mediated inversely by protein S-acyltransferases and de-S-acylation enzymes, but the de-S-acylation mechanism remains unclear in plant cells. Here, we characterized a group of putative protein de-S-acylation enzymes in Arabidopsis thaliana, including 11 members of Alpha/Beta Hydrolase Domain-containing Protein 17-like acyl protein thioesterases (ABAPTs). A robust system was then established for the screening of de-S-acylation enzymes of protein substrates in plant cells, based on the effects of substrate localization and confirmed via the protein S-acylation levels. Using this system, the ABAPTs, which specifically reduced the S-acylation levels and disrupted the plasma membrane localization of five immunity-related proteins, were identified respectively in Arabidopsis. Further results indicated that the de-S-acylation of RPM1-Interacting Protein 4, which was mediated by ABAPT8, resulted in an increase of cell death in Arabidopsis and Nicotiana benthamiana, supporting the physiological role of the ABAPTs in plants. Collectively, our current work provides a powerful and reliable system to identify the pairs of plant protein substrates and de-S-acylation enzymes for further studies on the dynamic regulation of plant protein S-acylation.

Oculopharyngodistal myopathy (OPDM) is associated with trinucleotide repeat expansions in LRP12 or GIPC1, but the genetic basis of many cases remains unknown. Yu et al. identify GGC repeat expansions in NOTCH2NLC in Chinese patients with OPDM, and provide evidence for possible underlying pathogenic mechanisms., Oculopharyngodistal myopathy (OPDM) is an adult-onset neuromuscular disease characterized by progressive ocular, facial, pharyngeal and distal limb muscle involvement. Trinucleotide repeat expansions in LRP12 or GIPC1 were recently reported to be associated with OPDM. However, a significant portion of OPDM patients have unknown genetic causes. In this study, long-read whole-genome sequencing and repeat-primed PCR were performed and we identified GGC repeat expansions in the NOTCH2NLC gene in 16.7% (4/24) of a cohort of Chinese OPDM patients, designated as OPDM type 3 (OPDM3). Methylation analysis indicated that methylation levels of the NOTCH2NLC gene were unaltered in OPDM3 patients, but increased significantly in asymptomatic carriers. Quantitative real-time PCR analysis indicated that NOTCH2NLC mRNA levels were increased in muscle but not in blood of OPDM3 patients. Immunofluorescence on OPDM muscle samples and expressing mutant NOTCH2NLC with (GGC)69 repeat expansions in HEK293 cells indicated that mutant NOTCH2NLC-polyglycine protein might be a major component of intranuclear inclusions, and contribute to toxicity in cultured cells. In addition, two RNA-binding proteins, hnRNP A/B and MBNL1, were both co-localized with p62 in intranuclear inclusions in OPDM muscle samples. These results indicated that a toxic protein gain-of-function mechanism and RNA gain-of-function mechanism may both play a vital role in the pathogenic processes of OPDM3. This study extended the spectrum of NOTCH2NLC repeat expansion-related diseases to a predominant myopathy phenotype presenting as OPDM, and provided evidence for possible pathogenesis of these diseases.

Defensins are the most diverse groups of antimicrobial peptides in invertebrate animals. In ticks, defensins show great potential as targets for tick control, and display future prospect for therapeutic drug development. In the present study, a novel defensin-like gene (Ds-defensin) contributing to the antimicrobial and antioxidant capacity of the tick Dermacentor silvarum was characterized. The full-length of the Ds-defensin gene was 382 bp, which displayed tissue-specific expression and was highly abundant in the salivary glands and carcasses of the adults. It encodes a 71-amino acid defensin-like protein, and the protein precursor is characterized by a 22-amino acid signal peptide and a 34-amino acid mature peptide. The peptide displayed potent activity against most of the tested gram-positive bacteria, including Staphylococcus aureus, S. carnosus and Nocardia asteroides, and one tested gram-negative bacterium, Psychrobacter faecalis. Scanning electron microscopy revealed that the cell wall and surface of treated bacteria became rough and gradually formed pores after a 30-min exposure to the Ds-defensin peptide. Additionally, the peptide also showed significant antioxidant capacity. The above results implied that the defensin-like peptide may play an important role in tick defense and the interaction with microorganisms.

The microstructure and mechanical properties of fine grained uranium prepared by equal channel angular pressing (ECAP) and subsequent intermediate heat treatment were investigated systematically by the confocal laser scanning microscope (CLSM), electron backscatter diffraction (EBSD) and split Hopkinson pressure bar (SHPB). The results show that the initial coarse grained uranium was refined from about 1000 to 6.5 μm prepared by ECAP at 3 passes and subsequent heat treatment, and the corresponding dynamic yield strength increased from 135 to 390 MPa. For the ECAPed uranium samples, the relationship between grain size and yield strength could be described by classical Hall–Petch relationship, and the fitting Hall–Petch relationship for the fine grained uranium samples prepared by ECAP was drawn.

Montmorillonite-loaded solid lipid nanoparticles with good biocompatibility, using Betaxolol hydrochloride as model drug, were prepared by the melt-emulsion sonication and low temperature-solidification methods and drug bioavailability was significantly improved in this paper for the first time to application to the eye. The appropriate physical characteristics were showed, such as the mean particle size, Zeta potential, osmotic pressure, pH values, entrapping efficiency (EE%) and drug content (DC%), all showed well suited for possible ocular application. In vitro release experiment indicated that this novel system could continuously release 57.83% drugs within 12 h owing to the dual drug controlled-release effect that was achieved by ion-exchange feature of montmorillonite and structure of solid lipid nanoparticles. Low irritability and good compatibility of nanoparticles were proved by both CAM-TBS test and cytotoxicity experiment. We first discovered from the results of Rose Bengal experiment that the hydrophilicity of the drug-loaded nanoparticles surface was increased during the loading and releasing of the hydrophilic drug, which could contribute to prolong the ocular surface retention time of drug in the biological interface membrane of tear-film/cornea. The results of in vivo pharmacokinetic and pharmacodynamics studies further confirmed that increased hydrophilicity of nanoparticles surface help to improve the bioavailability of the drug and reduce intraocular pressure during administration. The results suggested this novel drug delivery system could be potentially used as an in situ drug controlled-release system for ophthalmic delivery to enhance the bioavailability and efficacy.

Breast cancer is the most common type of cancer worldwide. However, the well-known molecular biomarkers are not enough to meet the needs of precision medicine. In search for novel targets in this regard, we reported ITSN1 (intersectin1) as one of the candidates through mRNA microarray analysis. In the present study, we reported that endocytic protein ITSN1-S exists not only in the cytoplasm but also in nuclei of breast cancer cells. ITSN1-S′ functional nuclear localization signal is within its residues 306–312. Its nuclear export signal (NES) resides within its SH3 domains. We also found, the interaction between the CC domain of nuclear ITSN1-S and the NT domain of nuclear DNA helicase II (NDH II) directly suppressed the DNA replication and nascent DNA synthesis by inhibiting the R-loops resolution in breast cancer cells. Furthermore, the interaction between the EH domains of cytoplasmic ITSN1-S and PI3KC2α inhibit cell migration and invasion by inactivating the PI3KC2α-AKT pathway. Our results were confirmed in both ITSN1 gene knockout cells and in vivo assays. Finally, our clinical data showed a potential application of the combined consideration of the cytoplasmic and nuclear ITSN1-S as an independent prognosis factor. In conclusion, our study revealed ITSN1-S′ novel positioning in the nuclei of breast cancer cells, its function in suppressing DNA replication, and its potential application in improved breast cancer prognosis.

The hydrogen evolution reaction (HER) represents one promising solution for energy and environmental sustainability. Nickel phosphide with various morphology has been recently investigated as promising earth abundant electrocatalysts for HER. Compared with three or two dimensional morphology, one dimensional (1D) nickel phosphide could provide larger specific surface area and hence improves the HER electrocatalytic performance. However, most reported 1D nickel phosphides show a small length-to-diameter ratio (less than 50). Herein, ultrahigh length-to-diameter ratio Ni2P nanowires synthesized by one-step phosphorization-sulfuration treatment are reported for the first time. The as-prepared nanowires have extremely high length to diameter ratio which ranges from 500 to 1000. The formation mechanism of such morphology is illustrated by a systematic study of the morphology, microstructure and elementary distribution of the nanowire array cathode. The ultralong nanowire morphology clearly helps improve the HER performances, since the self-supported Ni2P nanowire array cathode exhibits outstanding HER electrocatalytic activity and long-term durability in all of the acidic, alkaline, and neutral conditions.

Bismuth and rare earth elements have been identified as effective substituent elements in the iron garnet structure, allowing an enhancement in magneto-optical response by several orders of magnitude in the visible and near-infrared region. Various mechanisms have been proposed to account for such enhancement, but testing of these ideas is hampered by a lack of suitable experimental data, where information is required not only regarding the lattice sites where substituent atoms are located but also how these atoms affect various order parameters. Here, we show for a Bi-substituted lutetium iron garnet how a suite of advanced electron microscopy techniques, combined with theoretical calculations, can be used to determine the interactions between a range of quantum-order parameters, including lattice, charge, spin, orbital, and crystal field splitting energy. In particular, we determine how the Bi distribution results in lattice distortions that are coupled with changes in electronic structure at certain lattice sites. These results reveal that these lattice distortions result in a decrease in the crystal-field splitting energies at Fe sites and in a lifted orbital degeneracy at octahedral sites, while the antiferromagnetic spin order remains preserved, thereby contributing to enhanced magneto-optical response in bismuth-substituted iron garnet. The combination of subangstrom imaging techniques and atomic-scale spectroscopy opens up possibilities for revealing insights into hidden coupling effects between multiple quantum-order parameters, thereby further guiding research and development for a wide range of complex functional materials.

The physical mechanism driving the γ–α phase transition of face-centre-cubic (fcc) cerium (Ce) remains controversial until now. In this work, high-quality single crystalline fcc–Ce thin films were grown on Graphene/6H-SiC(0001) substrate, and explored by XRD and ARPES measurement. XRD spectra showed a clear γ–α phase transition at Tγ−α ≈ 50 K, which is retarded by strain effect from substrate comparing with Tγ−α (about 140 K) of the bulk Ce metal. However, APRES spectra did not show any signature of α-phase emerging in the surface-layer from 300 to 17 K, which implied that α-phase might form at the bulk-layer of our Ce thin films. Besides, an evident Kondo dip near Fermi energy was observed in the APRES spectrum at 80 K, indicting the formation of Kondo singlet states in γ–Ce. Furthermore, the DFT + DMFT calculations were performed to simulate the electronic structures and the theoretical spectral functions agreed well with the experimental ARPES spectra. In γ–Ce, the behavior of the self-energy’s imaginary part at low frequency not only confirmed that the Kondo singlet states emerged at TKS ≥ 80 K, but also implied that they became coherent states at a lower characteristic temperature (Tcoh ~40 K) due to the indirect RKKY interaction among f–f electrons. Besides, Tcoh from the theoretical simulation was close to Tγ−α from the XRD spectra. These issues suggested that the Kondo scenario might play an important role in the γ–α phase transition of cerium thin films.

To produce high-quality solar fuel, this work proposed a novel chemical looping in which a thermochemical cycle was hybridized with an electrochemical process. Specifically, sunlight was concentrated and split, short and medium solar spectrum was utilized for efficient PV-driven solid oxide electrolysis cell (SOEC), the rest spectrum was converted into heat to drive a three-step chemical looping steam reforming of methane (CLRM) cycle. The three-step CLRM consisted of reduction process with syngas production, oxidation process with hydrogen production, and reoxidation process of the oxygen carrier, respectively. By CLRM providing the reaction heat, the reactant of high-temperature steam and the reducing atmosphere required by cathode for SOEC, and simultaneously, SOEC providing high-temperature O2 for reoxidation process of CLRM, the thermochemical cycle can be well coupled with the electrochemical process and decrease the need for energy input. The design solar energy input to the novel cycle was supposed to be 55.6 MW, the solar-to-fuel efficiency can be expected to be 42.1%. This novel cycle allows the generation of a high-quality solar fuel with high efficiency and has a great potential in cost reduction.

The nanocatalysts of compound metal oxides ((La2CuO4)0.5(CNZ-1)0.5, denoted as LCO5-CNZ) composed of perovskite-like oxides La2CuO4 and CuO/ZnO/Al2O3 were prepared by co-precipitation and ball milling methods. The steam reforming of methanol (SRM) to H2 and CO2 over the nanocatalysts was experimentally studied at a molar ratio of 1.6 (H2O/methanol). The methanol solution catalyzed by LCO5-CNZ can be completely converted into H2, CO2 and a small amount of CO at the reaction temperature of 270 °C with a liquid hourly space velocity of 1.2 ml/(g·h). Simultaneously, under the same conditions, the catalysts of La2CuO4 and CuO/ZnO/Al2O3 were tested. Compared with the catalyst of pure La2CuO4, LCO5-CNZ showed higher methanol conversion rate and H2 yield. Compared with the conventional Cu-based catalyst of CuO/ZnO/Al2O3, LCO5-CNZ has both better CO selectivity and better H2 selectivity. It could be concluded that LCO5-CNZ with special structure has a significant improvement in catalyzing performance of SRM benefiting from the synergetic effect among perovskite-like La2CuO4 and Cu/Zn/Al oxides.

Juan Li,1 Shuangyan Tian,1 Qi Tao,2 Yawen Zhao,1 Ruyi Gui,1 Fan Yang,1 Lingquan Zang,3 Yanzhong Chen,4 Qineng Ping,5 Dongzhi Hou1 1Department of Pharmaceutics, Guangdong Provincial Engineering Center of Topical Precise Drug Delivery System, Guangdong Pharmaceutical University, Guangzhou, People’s Republic of China; 2CAS Key Laboratory of Mineralogy and Metallogeny & Guangdong Provincial Key Laboratory of Mineral Physics and Materials, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, People’s Republic of China; 3Department of Pharmacology, College of Pharmacy, Guangdong Pharmaceutical University, Guangzhou, People’s Republic of China; 4Guangdong Provincial Key Laboratory of Advanced Drug Delivery Systems, Guangdong Pharmaceutical University, Guangzhou, People’s Republic of China; 5College of Pharmacy, China Pharmaceutical University, Nanjing, People’s Republic of China Background: To date, the rapid clearance from ocular surface has been a huge obstacle for using eye drops to treat glaucoma, since it has led to the short preocular residence time and low bioavailability. Methods: The novel nanoparticles (NPs) were designed for topical ophthalmic controlled drug delivery system through intercalating the BH into the interlayer gallery of Na-montmorillonite (Na+Mt) and then further enchasing chitosan nanoparticles. The resulting nanoparticles had a positive charge (+29±0.18 mV) with an average diameter of 460±0.6 nm. Results: In vitro study of drug release profiles suggested controlled release pattern. The irritation experiment analysis on both human immortalized cornea epithelial cell (iHCEC) and chorioallantoic membrane-trypan blue staining (CAM-TBS) showed good tolerance for ocular tissues. It was interestingly found that the nanoparticles could enter into iHCEC from the result of cellular uptake experiment measured by confocal layer scan microscopy (CLSM). Meanwhile, multilayered iHCEC was used to simulate the barrier of corneal epithelial cells for in vivo preocular retention capacity study, which suggested that BH-Mt/CS NPs could prolong the retention time in comparison with BH solution. The ocular pharmacokinetics studied by microdialysis sampling technique showed that AUC0-t and MRT0-t of BH-Mt/CS NPs were 1.99-fold and 1.75-fold higher than those of BH solution, indicating higher bioavailability. Moreover, the study of blood drug concentration, few researchers have reported, showed that low level drug could enter into blood, suggesting lower systematic side effect. Importantly, pharmacodynamics studies suggested that BH-Mt/CS NPs could make a significant decreased intraocular pressure on glaucomatous rabbits. Conclusion: Inspired by these advance of montmorillonite/chitosan nanoparticles, we envision that the BH-Mt/CS NPs will be a potential carrier for BH, opening up the possible applications in glaucoma therapy. Keywords: montmorillonite, glaucoma, chitosan, betaxolol hydrochloride, preocular retention

Gold nanostars (GNSs) have received considerable attention in surface-enhanced spectroscopies, catalysis, biosensing, photothermal therapy, and photovoltaics because of their unique optical properties arising from the anisotropic structure. GNSs typically consisting of a central core and several protruding tips are usually synthesized by a seed-mediated growth approach, but the growth mechanism and optical properties have yet to be fully understood. Here, we systematically investigate the seed-mediated growth process of GNSs to gain an insight into the growth mechanism and evolution of their optical and photothermal properties. By tailoring the core size, tip length and tip angle, the main localized surface plasmon resonance (LSPR) peak wavelength can be broadly tuned from the visible to near-infrared (NIR) region. Our observations show that the protruding tips grow rapidly away from the central core at the initial growth stage, leading to a red-shift of the main LSPR peak. The preferential deposition of gold atoms onto the gold core takes place at the later growth stage, gradually blue-shifting the main LSPR peak. GNSs exhibit a large molar extinction coefficient ranging from 4.0 × 10

Oxide formation on surface of nitrogen-rich uranium nitride film/particles was investigated using X-ray photoelectron spectroscopy (XPS), auger electron spectroscopy (AES), aberration-corrected transmission electron microscopy (TEM), and high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) coupled with electron energy-loss spectroscopy (EELS). XPS and AES studies indicated that the oxidized layer on UN2-x film is ternary compound uranium oxynitride (UNxOy) in 5–10 nm thickness. TEM/HAADF-STEM and EELS studies revealed the UNxOy crystallizes in the FCC CaF2-type structure with the lattice parameter close to the CaF2-type UN2-x matrix. The work can provide further information to the oxidation mechanism of uranium nitride.

The determination of interstitial oxygen atom site in U2N3+xOy film could facilitate the understanding of the oxidation mechanism of α-U2N3 and the effect of U2N3+xOy on anti-oxidation. By comparing the similarities and variances between N K edge and O K edge electron energy loss spectra (EELS) for oxidized α-U2N3 and UO2, the present work looks at the local structure of nitrogen and oxygen atoms in U2N3+xOy film, identifying the most possible position of interstitial O atom.

To realize a short- and mid-term goal of sustainable development of solar fuel production, the possibility of effective hydrogen generation via methanol steam reforming at temperatures of 200 °C–300 °C inside a novel solar collector/reactor was experimentally demonstrated. With solar irradiation of 1000 W/m2, the solar collector-reactor achieved hydrogen generation rates up to 68.1 g/(m2·h), with solar-to-hydrogen efficiencies up to 41.3% and total energetic efficiencies (considering solar and fuel inputs) up to 76.6%, which is competitive with other solar fuel production technologies using high-temperature solar heat. Furthermore, the mechanism of upgrading the energy level of solar heat at 200 °C–300 °C was revealed based on the second law of thermodynamics and experimental results, where the catalyst was found to play a key role by decreasing the reaction temperature. The results obtained here indicate the possibility of utilizing the mid- and low-temperature solar heat for hydrogen production with high efficiency by upgrading the energy level of solar heat, and provide an enhancement to solar fuel production technologies with the development of this low-grade solar thermochemical technology in the near future.

Near-equiatomic, multi-component alloys with disordered solid solution phase (DSSP) are associated with outstanding performance in phase stability, mechanical properties and irradiation resistance, and may provide a feasible solution for developing novel uranium-based alloys with better fuel capacity. In this work, we build a machine learning (ML) model of disordered solid solution alloys (DSSAs) based on about 6000 known multicomponent alloys and several materials descriptors to efficiently predict the DSSAs formation ability. To fully optimize the ML model, we develop a multi-algorithm cross-verification approach in combination with the SHapley Additive exPlanations value (SHAP value). We find that the Delta S-C, Lambda, Phi(s), gamma and 1/Omega, corresponding to the former two Hume - Rothery (H - R) rules, are the most important materials descriptors affecting DSSAs formation ability. When the ML model is applied to the 375 uranium-bearing DSSAs, 190 of them are predicted to be the DSSAs never known before. 20 of these alloys were randomly synthesized and characterized. Our predictions are in-line with experiments with 3 inconsistent cases, suggesting that our strategy offers a fast and accurate way to predict novel multi-component alloys with high DSSAs formation ability. These findings shed considerable light on the mapping between the material descriptors and DSSAs formation ability.

The objective of this study is to achieve a higher solar-to-electricity conversion efficiency through solar-fossil hybrid thermal power systems compared to a solar-only power plant. The study reveals the thermodynamic details for the improved solar-to-electricity efficiency in a solar hybrid power plant. A correlation was established to describe the main factors influencing the thermodynamic performances, including higher collector efficiency, higher turbine efficiency and upgraded energy level of the moderate-temperature solar heat. This proposed mechanism can be applied to effectively integrate solar and fossil-fired energy in a power system. The studies took typical fossil-fired power plants to hybridize with solar heat in three approaches: preheating the feed water before it entering the boiler for coal-fired system; heating for generation of saturate steam or superheated steam in gas-fired combined cycle. The results indicate that the moderate-temperature solar and fossil hybridization technology can provide a promising direction for efficient utilization of low-grade solar heat.

Physiological reflexes and anatomical barriers render traditional eye drop delivery inefficient. We previously reported that drug-loaded nanoparticles and microspheres prepared from montmorillonite and Eudragit polymers exhibited good sustained-release and lowered intraocular pressure. Here, we compared the performance of optimized formulations to select the most suitable formulation for glaucoma therapy. We found that the microspheres had much higher encapsulation efficiency and drug loading than nanoparticles. Moreover, cytocompatibility experiments demonstrated that nanoparticles showed more severe cytotoxicity than microspheres, probably due to their smaller particles, enhanced cell uptake, and intracellular solubility. Interestingly, the pre-corneal retention time of nanoparticles reflected a clear advantage over microspheres, while the duration of the pharmacological effect of nanoparticles was not as good as that of microspheres: compared with the nanoparticle depressurization duration of only 8 h, the microspheres continuously depressurized for 12 h. The slower release of the microspheres and its micro-interaction mechanism with the discontinuous mucin layer of the tear film led to the inconsistency between duration of pharmacodynamics and fluorescence ocular retention time. In summary, the lower cytotoxicity and longer pharmacological effect of microspheres indicate their potential advantages for glaucoma applications.

Deformation twins in cast uranium strained to 4.2% and 6.2% by quasi static compression were investigated using electron backscattered diffraction and transmission electron microscopy. Twin types of {130}, ‘{172}’, {112} and ‘{176}’ were observed in present experiment. All the operative twin variants in each twin type have the highest Schmid factor among the equivalent variants. Some {130} twins in cast uranium were inclined to disappear during subsequent loading through the re-twinning processes with Schmid factor values greater than 0.4. The ‘(−176)’ variant was identified by indexing the electron diffraction pattern combining with the stereographic projection analysis. Twin pairs of ‘(−176)’–‘(−17−2)’ occurred in the adjacent grains were well matched with the geometric compatibility factor value of 0.933.

The chemical composition and microstructure of main inclusions in U-0.79 wt%Ti alloy were investigated by Scanning Augur electron spectroscopy (SAM) and High resolution scanning transmission electron microscopy (HRSTEM). SAM analysis showed the predominant inclusion in U-0.79 wt%Ti alloy was in the form of titanium carbonitrides. HRSTEM showed the high resolution atom image of titanium carbonitride inclusion and further verified the phase structure of titanium carbonitride inclusion was Ti(C,N). The after-hydriding analysis showed that the hydrogen attack preferentially occurred around most of the Ti(C,N) inclusions in U-0.79 wt%Ti alloy, the initial hydride growth showed a parabolic-like kinetic behavior with a reaction order of 0.6. The inclusion-oxide interface can act as preferential transport channel for hydrogen to reach the metal.

Shuangyan Tian,1 Juan Li,1 Qi Tao,2,3 Yawen Zhao,1 Zhufen Lv,4 Fan Yang,1 Haoyun Duan,5 Yanzhong Chen,4 Qingjun Zhou,5 Dongzhi Hou1 1Guangdong Engineering and Technology Research Center of Topical Precise Drug Delivery System, College of Pharmacy, Department of Pharmaceutics, Guangdong Pharmaceutical University, 2CAS Key Laboratory of Mineralogy and Metallogeny, 3Guangdong Provincial Key Laboratory of Mineral Physics and Materials, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, 4Guangdong Provincial Key Laboratory of Advanced Drug Delivery Systems, Guangdong Pharmaceutical University, Guangzhou, 5State Key Laboratory Cultivation Base, Shandong Provincial Key Laboratory of Ophthalmology, Shandong Eye Institute, Shandong Academy of Medical Sciences, Qingdao, China Background: Glaucoma is a serious eye disease that can lead to loss of vision. Unfortunately, effective treatments are limited by poor bioavailability of antiglaucoma medicine due to short residence time on the preocular surface. Materials and methods: To solve this, we successfully prepared novel controlled-release ion-exchange microparticles to deliver betaxolol hydrochloride (BH). Montmorillonite/BH complex (Mt-BH) was prepared by acidification-intercalation, and this complex was encapsulated in microspheres (Mt-BH encapsulated microspheres [BMEMs]) by oil-in-oil emulsion–solvent evaporation method. The BH loaded into ion-exchange Mt was 47.45%±0.54%. After the encapsulation of Mt-BH into Eudragit microspheres, the encapsulation efficiency of BH into Eudragit microspheres was 94.35%±1.01% and BH loaded into Eudragit microspheres was 14.31%±0.47%. Results: Both Fourier transform infrared spectra and X-ray diffraction patterns indicated that BH was successfully intercalated into acid-Mt to form Mt-BH and then Mt-BH was encapsulated into Eudragit microspheres to obtain BMEMs. Interestingly, in vitro release duration of the prepared BMEMs was extended to 12 hours, which is longer than both of the BH solution (2.5 hours) and the conventional BH microspheres (5 hours). Moreover, BMEM exhibited lower toxicity than that of BH solution as shown by the results of cytotoxicity tests, chorioallantoic membrane-trypan blue staining, and Draize rabbit eye test. In addition, both in vivo and in vitro preocular retention capacity study of BMEMs showed a prolonged retention time. The pharmacodynamics showed that BMEMs could extend the drug duration of action. Conclusion: The developed BMEMs have the potential to be further applied as ocular drug delivery systems for the treatment of glaucoma. Keywords: glaucoma, montmorillonite, controlled release, betaxolol hydrochloride, preocular retention, microspheres

The evolution of the oxide-overlayer's chemical nature on the surface of U–0.79 wt.%Ti alloy during vacuum annealing has been examined in situ by X-ray photoelectron spectroscopy (XPS). A specimen sheet of the alloy covered by oxide films is heated from room temperature to 700 °C in vacuum. It is found that the UO 2+ x outer oxide layer starts to be reduced to UO 2 at 200 °C. Between 300 and 400 °C, an oxycarbide (UO x C y ) layer is observed due to the reaction between UO 2 and carbon. Above 500 °C, UO x C y decomposes and the surface covered oxide layer starts to be reduced to the metallic state, meanwhile, a thermal driven segregation of Ti to the surface is also observed.

Nanocatalysts of compound metal oxides (La2CuO4)x(CNZ-1)1−x (x = 0.3, 0.5, 0.7) were prepared. Steam reforming of methanol (SRM) over these nanocatalysts was experimentally studied at a H2O/methanol molar ratio of 1.6. The results showed that the methanol solution catalyzed by all catalysts synthesized in this work could be completely converted into H2, CO2 and a small amount of CO below a reaction temperature of 270 °C with a liquid hourly space velocity (LHSV) of 1.2 ml/(g·h). The catalysts of La2CuO4 and CuO/ZnO/Al2O3 were tested under the same operating conditions. Compared with La2CuO4, LCOx-CNZ showed better performance with a higher methanol conversion rate and H2 yield. Conversely LCO5-CNZ had better CO and H2 selectivity compared with CuO/ZnO/Al2O3. LCO3-CNZ showed good competitiveness in all four above aspects when operated at 150–270 °C. It could be concluded that LCOx-CNZ with special structures provided a significant improvement in catalytic performance of SRM benefiting from the synergistic effect among La2CuO4 and CuZnAl oxides. Thermodynamics analysis and experiments using a hybrid power generation system were applied with the above catalysts. Under direct normal irradiation at 915 W/m2 and a reaction temperature of 230 °C, LCO3-CNZ showed 9.7% higher H2 yield and 3.9% higher net solar power generation efficiency than did Cu/Zn/Al oxides.

The performance of a photovoltaic device is strongly dependent on the light harvesting properties of the absorber layer as well as the charge separation at the donor/acceptor interfaces. Atomically thin two-dimensional transition metal dichalcogenides (2-D TMDCs) exhibit strong light-matter interaction, large optical conductivity, and high electron mobility; thus they can be highly promising materials for next-generation ultrathin solar cells and optoelectronics. However, the short optical absorption path inherent in such atomically thin layers limits practical applications. A heterostructure geometry comprising 2-D TMDCs (e.g., MoS2) and a strongly absorbing material with long electron-hole diffusion lengths such as methylammonium lead halide perovskites (CH3NH3PbI3) may overcome this constraint to some extent, provided the charge transfer at the heterostructure interface is not hampered by their band offsets. Herein, we demonstrate that the intrinsic band offset at the CH3NH3PbI3/MoS2 interface can be overcome by creating sulfur vacancies in MoS2 using a mild plasma treatment; ultrafast hole transfer from CH3NH3PbI3 to MoS2 occurs within 320 fs with 83% efficiency following photoexcitation. Importantly, our work highlights the feasibility of applying defect-engineered 2-D TMDCs as charge-extraction layers in perovskite-based optoelectronic devices.