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Encapsulating a certain guest molecule in an assigned molecular compartment and then endowing the corresponding potential remains a huge challenge for metal-organic frameworks. To this end, we demonstrate a good example, for the first time, based on an actinide-based MOF. The used MOF (namely, ECUT-300) shows a unique uranyl-TPE anionic skeleton with three distinct cages, viz., mesopore A (2.8 nm), mesopore B (2.0 nm), and micropore C (0.9 nm). Through solid-liquid reaction, a RhB+ molecule can be encapsulated into ECUT-300 with the exact location in mesopore B, whereas the encapsulation of a metal-organic cation of [Fe(tpy)2]3+ was observed with the location in micropore C, suggesting unprecedented classified encapsulation. Impressively, the potential of the resulting guest@MOF composites is also highly dependent on the type of encapsulated guest molecules, for example, white-light emission for RhB+ and selective adsorption of C2H2 over CO2 for [Fe(tpy)2]3+.

In the presence of the predatory rotifer Asplanchna, some Brachionus and Keratella species develop inducible morphological, behavioral, and life history defenses that enable prey to survive predation pressure. However, whether clones belonging to the same rotifer species but with different behaviors (attached and free-swimming) exhibit divergent responses in morphology and life history remains largely unknown. In this study, neonates of an attached and a free-swimming clone of B. dorcas were exposed to media conditioned by A. brightwellii neonates at densities of 0 (control), 40, 80, and 160 ind l−1 for 24 h, and their morphological and life-table demographic parameters were measured and calculated. We showed that the Asplanchna kairomone significantly increased the propensity to attach in the attached clone only, with attached individuals effectively protected from Asplanchna predation. In response to increasing Asplanchna kairomone concentration, the attached clone did not show any morphological changes, but it did exhibit a decreased net reproductive rate and intrinsic rate of population increase. The free-swimming clone developed elongated posterolateral spines and a decreased intrinsic rate of population increase, as well as a decrease in the proportion of sexual offspring. Thus, both clones exhibited reproductive costs.

Synthesis of supported Pd-based bimetallic catalysts is of great importance in the heterogeneous catalysis field owing to their optimal geometric and electronic effects. Downsizing active metals to ultrasmall nanocluster ( 93% to styrene, demonstrating the alloying and small-size effects in the bimetallic nanocluster catalysts.

Ca2+ , a ubiquitous but nuanced modulator of cellular physiology, is meticulously controlled intracellularly. However, intracellular Ca2+ regulation, such as mitochondrial Ca2+ buffering capacity, can be disrupted by 1 O2 . Thus, the intracellular Ca2+ overload, which is recognized as one of the important cell pro-death factors, can be logically achieved by the synergism of 1 O2 with exogenous Ca2+ delivery. Reported herein is a nanoscale covalent organic framework (NCOF)-based nanoagent, namely CaCO3 @COF-BODIPY-2I@GAG (4), which is embedded with CaCO3 nanoparticle (NP) and surface-decorated with BODIPY-2I as photosensitizer (PS) and glycosaminoglycan (GAG) targeting agent for CD44 receptors on digestive tract tumor cells. Under illumination, the light-triggered 1 O2 not only kills the tumor cells directly, but also leads to their mitochondrial dysfunction and Ca2+ overload. An enhanced antitumor efficiency is achieved via photodynamic therapy (PDT) and Ca2+ overload synergistic therapy.

Although a plethora of nonviral gene vectors have been developed for potential gene therapy, imageable gemini surfactants with stimuli-responsiveness and high transfection efficiency are still scarce for gene delivery. Herein, three gemini amphiphiles (DEDPP-4/8/12) consisting of an aggregation-induced emission (AIE) central fluorophore: 5,6-diphenylpyrazine-2,3-diester (DEDPP), decorated with triazole-[12]aneN3 as the hydrophilic moiety and alkyl chains of various lengths as the hydrophobic moiety, were designed and synthesized for trackable gene delivery via optical imaging. All three amphiphiles exhibited ultralow critical micelle concentrations (CMCs) (up to 3.40 × 10-6 M), prominent two-photon absorption properties, and solvatochromic fluorescence. Gel electrophoresis assays demonstrated that the migration of plasmid DNA was completely retarded after condensation with these gemini amphiphiles at low concentrations (up to 10 μM). In addition, the ester bond in these amphiphiles may facilitate vector degradation and DNA release, in response to esterase and the acidic environment inside cells. Upon self-assembly with DOPE to form liposomes, DEDPP-8/DOPE achieved the best transfection efficiency in four cell lines, and the transfection efficiency of DEDPP-8/DOPE in HeLa cell lines was 23.5-fold higher than that of Lipo2000, which is unusually high for small organic molecule-based nonviral vectors. Furthermore, excellent transfection efficiency of DEDPP-8/DOPE was obtained in the presence of serum, and the red fluorescence protein (RFP) gene was successfully transfected in zebrafish embryos. Both one- and two-photon fluorescence imaging clearly demonstrated the delivery process of plasmid DNA. This study demonstrated that gemini-type amphiphiles composed of a two-photon fluorophore core conjugated with triazole-[12]aneN3 via an ester bond afforded an unprecedentedly high transfection efficiency with excellent biocompatibility, which may provide new insights for the design and development of multifunctional nonviral gene vectors for imageable gene delivery.

Nagilactone E (NLE), a natural product with anticancer activities, is isolated from Podocarpus nagi. In this study, we reported that NLE increased programmed death ligand 1 (PD-L1) expressions at both protein and mRNA levels in human lung cancer cells, and enhanced its localization on the cell membrane. Mechanistically, NLE increased the phosphorylation and expression of c-Jun, and promoted the localization of c-Jun in the nucleus, while silencing of c-Jun by small interfering RNA (siRNA) reduced NLE-induced PD-L1. Further study showed that NLE activated the c-Jun N-terminal kinases (JNK), the upstream of c-Jun, and its inhibitor SP600125 reversed the NLE-increased PD-L1. Moreover, NLE-induced PD-L1 increased the binding intensity of PD-1 on the cell surface. In summary, NLE upregulates the expression of PD-L1 in lung cancer cells through the activation of JNK-c-Jun axis, which has the potential to combine with the PD-1/PD-L1 antibody therapies in lung cancer.

The high surface energy of nanomaterials endows them a metastable nature, which greatly limits their application. However, in some cases, the degradation process derived from the poor stability of nanomaterials offers an unconventional approach to design and obtain functional nanomaterials. Herein, based on the poor stability of ZnSe-[DETA]0.5 hybrid nanobelts, we developed a new strategy to chemically graphitize and functionalize graphene oxide (GO). When ZnSe[DETA]0.5 hybrid nanobelts encountered a strong acid, they were attacked by H+ cations and could release highly reactive Se2− anions into the reaction solution. Like other common reductants (such as N2H4·H2O), these Se2− anions exhibited an excellent ability to restore the structure of GO. The structural restoration of GO was greatly affected by the reaction time, the volume of HCl, and the mass ratio between GO and ZnSe[DETA]0.5 nanobelts. By carefully controlling the reaction process and the post-processing process, we finally obtained several Se-based reduced GO (RGO) nanocomposites (such as ZnSe/Se-RGO, ZnSe-RGO, and Se-RGO) and various selenide/metal-RGO nanocomposites (such as Ag2Se-RGO, Cu2Se-RGO, and Pt-RGO). Although the original structure and composition of ZnSe[DETA]0.5 nanobelts are destroyed, the procedure presents an unconventional way to chemically graphitize and functionalize GO and thus provides a new material synthesis platform for nanocomposites.

Because of the permission of the manipulations of modular construction on the atomic level, covalent organic frameworks (COFs) have attracted extensive attention in the electrocatalytic field. Owing to the lack of metal sites in pristine COFs constructed only by metal-free organic building units, it generally exhibits extremely low electrocatalytic activity. Thereby, linking metal sites on the backbone of pyrolysis-free COFs but not loading them on the surface to enhance the electrocatalytic activity is highly desirable but still remains a huge challenge. To this end, herein, we report an efficient and general cation-exchange strategy to synthesize Ni/Fe metal-ion-incorporated COFs (NixFe1-x@COF-SO3) for the oxygen evolution reaction (OER) based on the fundamental structure design of COFs. Impressively, the turnover frequency (TOF) value in Ni0.5Fe0.5@COF-SO3 reaches 0.14 s-1 at the overpotential of 300 mV, which outperforms most recently reported OER electrocatalysts, indicative of ultrahigh metal-atom utilization efficiency.

Tumor targeting provided more effective gene therapy. Bcl-2 is an oncogene, and Bcl-2 small interfering RNA (Bcl-2 siRNA) can inhibit its expression. Here, a fluorescent and gene-loading capacity vector DPL, derived from diketopyrrolopyrrole (DPP), was developed for Bcl-2 siRNA-targeted delivery and tumor imaging in vitro and in vivo. The vector DPL showed a significant emission enhancement after interacting with siRNA, which was used to track the gene transfer process. Compared to commercial transfection reagent Lipo 2000, DPL obviously downregulated the Bcl-2 protein expression and exhibited excellent antitumor efficacy with less Bcl-2 siRNA. Importantly, DPL can target tumors to transport Bcl-2 siRNA to tumor sites in vivo based on the enhanced permeability and retention (EPR) effect for effective in vivo tumor therapy. This work inspired us to design and synthesize a multifunctional gene vector for tumor targeting and gene therapy.

Herein, we obtained chemically bonded Bi2S3-Graphene/TiO2 composites using a facile one pot-hydrothermal method. During the hydrothermal reaction, both of the reduction of graphene oxide to graphen...

Herein, we report a microporous carbon nanomaterial that was generated from a nanoscale covalent organic framework precursor via a simple pyrolysis approach. The obtained carbon-based nanoparticles possessed a broad NIR absorption capacity and exhibited a high level of photothermal conversion ability (η = 50.6%) in the NIR-II biowindow. Its excellent PTT antitumor efficiency was fully evidenced by in vitro and in vivo experiments under 1064 nm laser irradiation.

A huge amount of seabed acoustic reflectivity data has been acquired from the east to the west side of the southern Adriatic Sea (Mediterranean Sea) in the last 18 years by CNR-ISMAR. These data have been used for geological, biological and habitat mapping purposes, but a single and consistent interpretation of them has never been carried out. Here, we aimed at coherently interpreting acoustic data images of the seafloor to produce a benthic habitat map of the southern Adriatic Sea showing the spatial distribution of substrates and biological communities within the basin. The methodology here applied consists of a semi-automated classification of acoustic reflectivity, bathymetry and bathymetric derivatives images through object-based image analysis (OBIA) performed by using the ArcGIS tool RSOBIA (Remote Sensing OBIA). This unsupervised image segmentation was carried out on each cruise dataset separately, then classified and validated through comparison with bottom samples, images, and prior knowledge of the study areas.

Apple pomace was explored as alternative feedstock for producing bacterial cellulose (BC) by Gluconacetobacter xylinus following a cellulase saccharification performed after pretreatment of 1-allyl-3-methylimidazolium chloride ([AMIM]Cl). The dissolving process of apple pomace cellulose was observed by polarized light microscopy (PLM). As FT-IR and XRD results demonstrated, the IL pretreatment proved to be a physical process and no changes in the crystalline structure occurred during the pretreatment. However, the SEM result showed that more fissures and breakages appeared on the surface of pomace microfibers after IL-pretreating, which increased the contact area with cellulase and improved the enzymatic hydrolysis efficiency. An enhancing effect on the BC yield has been observed, 27% higher yield of BC obtained from hydrolysate as compared to sucrose-based medium indicates efficiency of IL-treated apple pomace to serve as high quality feedstock in BC production.

In a seminal work, Gozar et al. reported on the high-temperature interface superconductivity in bilayers of insulating La2CuO4 and metallic La2−xSrxCuO4 (x=0.45). An interesting question to address is how general and robust this interface superconductivity is. In the past, the cuprate bilayers were grown in a unique atomic-layer molecular beam epitaxy system, with a Sr doping range of x≤0.47, and the atomically flat interface was thought to be indispensable. Here, we have fabricated bilayers of La2CuO4 and La2−xSrxCuO4 by pulsed laser deposition. We have tried to extend the nominal doping range of Sr from the previous maximum of 0.47 to the present 1.70 (the nominal Sr content in the targets). X-ray diffraction result indicates that our La2−xSrxCuO4 films with x≤0.60 have very high crystalline quality; but the film crystalline structure degrades gradually with further increasing x, and finally the structure is fully lost when x reaches 1.40 and higher. Although the film quality scatters dramatically, our experiments show that there exists superconductivity for bilayers in nearly the entire over-doped Sr range, except for a non-superconducting region at x∼0.80. These observations demonstrate that the interface superconductivity in copper oxides is very general and robust.

The availability of high-resolution satellite precipitation measurement products provides an opportunity to monitor precipitation over large and complex terrain and thus accurately evaluate the climatic, hydrological and ecological conditions in those regions. The Global Precipitation Measurement (GPM) mission is an important new program designed for global satellite precipitation estimation, but little information has been reported on the applicability of the GPM’s products for the Tibetan Plateau (TP). The object of this study is to evaluate the accuracy of the Integrated Multi-Satellite Retrievals for GPM (IMERG) Final Run product under different terrain and climate conditions over the TP by using 78 ground gauges from April 2014 to December 2017. The results showed the following: (1) the 3-year average daily precipitation estimation in the IMERG agrees well with the rain gauge observations (R2=0.58, P

To explore the role of dislocation slip mode playing in the size effect of mechanical behavior of metallic materials, the tensile behavior of Cu-5at.%Mn and Cu-20at.%Mn alloys with thickness (t) spanning from 0.1 to 2.0 mm is investigated. The results reveal that the yield strength σYS of Cu-5at.%Mn alloy displays an independence of thickness, whereas the ultimate tensile strength σUTS and the uniform elongation δ show an obvious size effect. The σUTS and δ first slightly decrease as t is reduced from 2.0 to 0.5 mm, but evidently drop when t is below 0.5 mm. A similar size effect is also exhibited in Cu-20at.%Mn alloy; however, the variation trend of “the smaller the weaker” in size effect can be weakened by the planar slip of dislocations occurring during the deformation of this alloy.

Owing to the microstructural inhomogeneities and residual stresses that are generated during welding, welded joints are the weakest parts of structures. Nanoindentation, a non-destructive technique...

Rational design of practical probes with excellent specificity and improved optical properties for a particular enzyme is always a big challenge. Herein, a practical and highly specific fluorescent probe for carboxylesterase 1 (CES1) was rationally designed using meso-carboxyl-BODIPY as the basic fluorophore based on the substrate preference and catalytic properties of CES1. Following molecular docking-based virtual screening combined with reaction phenotyping-based experimental screening, we found that MMB (probe 7) exhibited the optimal combination of sensitivity and specificity toward human CES1 in contrast to other ester derivatives. Under physiological conditions, MMB could be readily hydrolyzed by CES1 and release MCB; such biotransformation brought great changes in the electronic properties at the meso position of the fluorophore and triggered a dramatic increase in fluorescence emission around 595 nm. Moreover, MMB was cell membrane permeable and was successfully applied to monitor the real activities of CES1 in various biological samples including living cells, tissue slices, organs, and zebrafish. In summary, this study showed a good example for constructing specific fluorescent probe(s) for a target enzyme and also provided a practical and sensitive tool for real-time sensing of CES1 activities in complicated biological samples. All these findings would strongly facilitate high-throughput screening of CES1 modulators and the studies on CES1-associated physiological and pathological processes.

Recent research indicates that the human infertility rate is increasing. Although various reasons have been hypothesized for the growing infertility rate, environmental contaminants are potentially important causal agents associated with this change. Chemical contaminants are widespread throughout our environment and human exposure is virtually unavoidable. The overall contribution of environmental exposure to infertility is unknown, but studies involving occupational exposure, together with results from animal experiments, suggest that environmental contaminants may adversely affect fertility. We reviewed the adverse effects of environmental exposure on fertility and related reproductive outcomes. Environmental contaminants covered in this review include heavy metals, organic solvents, pesticides and endocrine disrupting chemicals. It is hoped that this review will highlight the need for further research in this area.

Carboxylesterase 1 (CES1), one of the most abundant serine hydrolases in mammals, has drawn much attentions in recent years, owing to this enzyme involves in many physiological processes via hydrolysis of both endogenous esters and xenobiotic esters. Herein, to real-time monitor the activities of CES1 in various biological systems, a practical and isoform-specific fluorescent probe was developed on the basis of the substrate preference of CES1, as well as the structural and optical properties of BODIPY dyes. After screening of a panel of BODIPY ester derivatives, probe 1 displayed the best combination of specificity, sensitivity, enzymatic kinetics and applicability for monitoring CES1 activities in real samples. This probe was successfully used to detect CES1 activities in several biological systems including tissue preparations, living cells, tissue slices and zebrafish. Furthermore, the biomedical applications of probe 1 for screening of CES1 inhibitors were also demonstrated using tissue preparations or living cells as enzyme sources. In summary, a practical and broadly applicable tool for real-time monitoring CES1 in biological systems was developed and well-characterized, which held great promise for further investigations on CES1-associated drug discovery, clinical practice and fundamental research.

Melanosis developed in shrimp (Penaeus vannamei) is mainly initiated by polyphenoloxidase (PPO), thus understanding of the characteristics of PPO in shrimp is important for controlling the melanosis of shrimp. The shrimp cephalothorax turns black most rapidly amongst all the tissues during the chilled storage. Crude PPO extracted from this cephalothorax has an optimal pH of 6.0 and an optimal temperature of 50 °C. PPO is relatively stable under neutral and weak alkaline conditions (pH 5.5–9.0) and the temperature range of 25–35 °C. The kinetic parameters K(m) and V(max) were recorded as 3.02 mM and 54.3 U/mg of protein, respectively, using L-Dopa as a substrate. The molecular weight of PPO was estimated as 200–220 kDa by an activity staining test. A hydroxypyridinone derivative, 5-hydroxy-1-octyl-4-oxo-1,4-dihydropyridine-2-carbaldehyde O-ethyl oxime, was demonstrated to efficiently inhibit the PPO, indicating that this compound might find application as a shrimp preservative.

In order to explore the potential of a novel tyrosinase inhibitor, namely the hydroxypyridinone derivative (5-hydroxy-1-octyl-4-oxo-1,4-dihydropyridine-2-carbaldehyde O-ethyl oxime, HPO), for shrimp preservation, six bacterial isolates from shrimp (Penaeus vannamei) (S1, S2, S3, S5, S6 and S7) were investigated. These bacteria were identified as Shewanella amazonensis, Shewanella haliotis, Microbacterium oxydans, Photobacterium damselae, Staphylococcus haemolyticus and Bacillus cereus. The antimicrobial effect of HPO on these bacteria was evaluated by an inhibition zone test, together with minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) assays. The results indicated that HPO possessed a stronger inhibitory effect than kojic acid. The antioxidant activity of HPO was evaluated by determining its 1,1-diphenyl-2-picrylhydrazyl (DPPH) and superoxide anion radical scavenging ability. The preservation effect on shrimp (Penaeus vannamei) of HPO was assessed by determining the quality indicators of the shrimp during the storage, including total bacterial count, pH value, total basic volatile nitrogen content, thiobarbituric acid reactive substances (TBARS) and by sensory evaluation. It was found that treatment of shrimp with HPO effectively extended the shelf life to 10 days at 4 °C. In the same assay, the shelf life of shrimps treated with 4-hexylresorcinol, kojic acid, and the control group was found to be 10, 6, and 4 days, respectively. The treatment of shrimps with HPO in combination with 0.1% citric acid further extended its shelf life to 12 days. Clearly, HPO could be applied as a shrimp preservative due to its potent anti-browning, antimicrobial and antioxidant activities.

Three new D–π–A type dyes 1–3 comprising triphenylamine as the core and [12]aneN3 or benzothiazole (Bz) as branches were designed as two-photon luminescent non-viral gene vectors with tracking ability. Compound 1 with one Bz and one [12]aneN3 branches as well as a heavy atom, I, has higher toxicity and lower transfection efficiency. Compound 2 containing two [12]aneN3 branches shows a good mitochondria targeting property and can condense DNA at 5 μM, in particular it exhibits 1.70 times higher red fluorescent gene (RFG) transfection efficiency than Lipofectamine 2000 in the presence of cell penetrating peptides (CPPs). Compound 3 with two Bz-branches and one [12]aneN3 moiety shows the largest two-photon absorption cross section of 309 GM at 760 nm among the three dyes and is able to localize in mitochondria with an overlap coefficient of 0.99. With the advantages of strong two-photon absorption, good DNA condensation, and mitochondria targeting ability, compound 2 was used to monitor the process of cellular uptake, DNA translocation and release, RFG expression in cells, and RFG expression in a rat tumor using a two-photon microscope. To the best of our knowledge, this study represents the first example of a mitochondria targeting two-photon fluorescent organic molecule in gene transfection in vitro and in vivo.

We demonstrate herein an effective cascade reaction for combined photodynamic and starvation therapy in treating breast tumors based on a photosensitizer and CO prodrug decorated NMOF. The PDT-induced ROS can further trigger CO release, and the high antitumor efficiency derived from both 1O2 and CO is well confirmed by in vitro assays and in vivo trials.

An unprecedented asymmetric catalytic (4 + 2) annulation reaction of aryl-substituted γ-methylidene-δ-valerolactones (GMDVs) with isatin-derived para-quinone methides (p-QMs) has been developed under the catalysis of palladium(0) and (S,S,S)-(-)-Xyl-SKP, offering a new approach for the diastereo- and enantioselective synthesis of chiral cyclohexadienone-fused cyclohexyl spirooxindoles. Significantly, three highly congested contiguous tetrasubstituted carbon atoms embedded in bispirocyclic skeleton, of which two are vicinal quaternary stereogenic centers, are forged in an effective and selective manner (up to 99% yield, up to 95% ee, >20/1 dr). The current reaction represents the first exploration of enantioselective catalytic (4 + 2) annulation forming the six-membered carbocycles in the chemistry of both GMDVs and p-QMs.

Cancer nanomedicine is one of the most promising domains that has emerged in the continuing search for cancer diagnosis and treatment. The rapid development of nanomaterials and nanotechnology provide a vast array of materials for use in cancer nanomedicine. Among the various nanomaterials, covalent organic frameworks (COFs) are becoming an attractive class of upstarts owing to their high crystallinity, structural regularity, inherent porosity, extensive functionality, design flexibility, and good biocompatibility. In this comprehensive review, recent developments and key achievements of COFs are provided, including their structural design, synthesis methods, nanocrystallization, and functionalization strategies. Subsequently, a systematic overview of the potential oncotherapy applications achieved till date in the fast-growing field of COFs is provided with the aim to inspire further contributions and developments to this nascent but promising field. Finally, development opportunities, critical challenges, and some personal perspectives for COF-based cancer therapeutics are presented.

Platycodonis Radix, the root of Platycodon grandiflorum (Jacq.) A. DC., is a well-known edible herbal medicine. It is a common vegetable used for the preparation of side dish, kimchi, dessert, and tea. Besides, it has been used to treat respiratory disease including cough, excessive phlegm, and sore throat for a long history. In the past decades, the bioactive components and the pharmacological activities of Platycodonis Radix have been widely investigated. Thereinto, platycodins, the oleanane-type triterpenoid saponins were demonstrated to be the main bioactive components in Platycodonis Radix, and more than 70 platycodins have been identified up to date. This paper mainly reviewed the phytochemistry, pharmacological activities (apophlegmatic, anti-tussive, anti-inflammatory, anti-cancer, anti-obesity, anti-diabetic, immunomodulatory, cardiovascular protective, and hepatoprotective activities, etc.), toxicology and pharmacokinetics of platycodins isolated from Platycodonis Radix, aiming to promote further investigation on therapeutic potential of these platycodins.

Organic dyes generating from many industries are considered as a potential source of water-pollution and have negative effects on human health. The present study was aimed to construct a green synthesis method for fabrication of ZnS-based dual nano-semiconductors and to compare the photocatalytic properties for removing cationic and anionic dyes. ZnS nanoparticles were synthesized using a template synthesis in bovine serum albumin (BSA) solution and then ZnS/PbS, ZnS/CdS and ZnS/Ag2S dual nano-semiconductors were prepared using ion-exchange method. Prepared nano-semiconductors were characterized by using HR-TEM, XRD, FTIR, TG/DTA and AAS. Moreover, photocatalytic activity of prepared nano-semiconductors was tested against Rhodamine B (cationic dye) and Methyl Orange (anionic dye). Results revealed that a controllable ZnS/PbS, ZnS/CdS and ZnS/Ag2S ratio in nano-semiconductors can be achieved by adjusting the ion-exchange time. Prepared ZnS based composites exhibited higher photocatalytic efficiency than that of ZnS alone. In addition, photocatalytic activity of ZnS-based dual nano-semiconductors was found to be dependent upon composition and ratio of sulphides in nano-semiconductors with environmental pH. It was concluded that the combination of template synthesis and ion-exchange method is a feasible approach to fabricate new photocatalysts with higher photocatalytic activity.

Reduction of lipid absorption has been recognized as an attractive approach for the discovery of new drugs to treat obesity and overweight. The leave extract of Ginkgo biloba has been widely used for the treatment of metabolic diseases (such as hyperlipidemia) in both eastern and western countries, but the bioactive compounds in Ginkgo biloba and the underlying mechanism have not been fully characterized. This study aimed to investigate the inhibition potentials and mechanism of major biflavones from G. biloba on pancreatic lipase (PL), a key target regulating lipid absorption. The results clearly demonstrated that all tested biflavones in G. biloba including isoginkgetin, bilobetin, ginkgetin and sciadopitysin, displayed strong to moderate inhibitory effects on PL with the IC50 values ranging from 2.90 μM to 12.78 μM. Further investigations on both inhibition kinetic analyses and docking simulations demonstrated that isoginkgetin, bilobetin and ginkgetin were potent PL inhibitors (Ki

Pancreatic lipase (PL), a key enzyme responsible for the hydrolysis of triacylglycerides in the gastrointestinal tract, has been identified as the therapeutic target for the regulation of lipid absorption. In the present study, six major constituents from a famous Chinese herbal medicine Cortex Mori Radicis (also named sangbaipi in Chinese), have been collected and their inhibitory effects on PL have been carefully investigated and well characterized by a fluorescence-based assay. The results clearly demonstrated that all tested bioactive constituents from Cortex Mori Radicis including sanggenone C (SC), sanggenone D (SD), kuwanon C (KC), kuwanon G (KG), morin and morusin displayed strong to moderate inhibitory effects towards PL with the IC50 values ranging from 0.77 μM to 20.56 μM. Further investigations on inhibition kinetics demonstrated that SC, SD, KC and KG functioned as potent and mixed inhibitors against PL-mediated 4-MU oleate hydrolysis, with the Ki values less than 5.0 μM. Furthermore, molecular docking simulations demonstrated that SD (the most potent PL inhibitor from Cortex Mori Radicis) could create strong interaction with Ser152 (the key amino acid in the catalytic triad) of PL via hydrogen bonding. All these findings provided a new powerful evidence for explaining the hypolipidemic effect of Cortex Mori Radicis, also suggested that some abundant natural compounds in this herbal medicine could be served as lead compounds for the development of new PL inhibitors.

The behavior of silicon (Si) and iron (Fe) and their isotope fractionation during carbonate weathering and terra rossa formation are unclear. Here, we focus on a 4.05-m-thick terra rossa profile developed on dolomite in the Yunnan-Guizhou Plateau, China. We measured the mineral and geochemical composition, magnetic susceptibility and Si and Fe isotopic composition of the terra rossa, ferromanganese concretions (FMCs), and the dolomite and its insoluble residues. The results indicate that there is absolute accumulation of Si and Fe during dolomite weathering and terra rossa formation, due to the extraneous input of dissolved Si and Fe. This means that the insoluble residues of dolomite are not the only source for terra rossa formation. In addition, we suggest that the high frequency-dependent magnetic susceptibility (χfd, %) and rubification of the terra rossa are the result of the oxidation of extraneous dissolved Fe and the neoformation of finely dispersed Fe oxides. Overall, the terra rossa is characterized by the enrichment of light Si and Fe isotopes, compared with insoluble dolomite residues and bulk dolomite. The extraneous input of dissolved Fe is characterized by a light isotopic signature, whereas the Si isotopic signature of the extraneous source is unclear due to modification by late desilicification. Si isotope fractionation in the terra rossa is mainly controlled by chemical weathering and associated mobilization and redistribution of Si. The δ30Si values of terra rossa decrease with increasing weathering intensity, while the re-precipitation of mobilized Si leads to the significant enrichment of isotopically heavy Si in the basal terra rossa. The δ30Si values of terra rossa are not significantly affected by the adsorption of the Fe and Al (oxyhydr)oxides. By contrast, the major process that fractionates Fe isotopes in the dolomite-terra rossa weathering system is unclear. In the terra rossa profile, the δ56Fe values of the FMCs are significantly lower than those of the surrounding terra rossa matrix. These low δ56Fe signatures of the FMCs reflect the preferential translocation of the light Fe isotope, while the FMCs may be able to record the low-δ56Fe characteristics of pore water.

The propagation of shear horizontal (SH) surface waves in piezoelectric semi-infinite bodies is investigated theoretically. The surface stress exerting on the boundary is taken into account through...

The paper summarizes results of the China Energy Modeling Forum's (CEMF) first study. Carbon emissions peaking scenarios, consistent with China's Paris commitment, have been simulated with seven national and industry-level energy models and compared. The CO2 emission trends in the considered scenarios peak from 2015 to 2030 at the level of 9–11 Gt. Sector-level analysis suggests that total emissions pathways before 2030 will be determined mainly by dynamics of emissions in the electric power industry and transportation sector. Both sectors will experience significant increase in demand, but have low-carbon alternative options for development. Based on a side-by-side comparison of modeling input and results, conclusions have been drawn regarding the sources of emissions projections differences, which include data, views on economic perspectives, or models' structure and theoretical framework. Some suggestions have been made regarding energy models' development priorities for further research. Keywords: Carbon emissions projections, Climate change, CO2 emissions peak, China's Paris commitment, Top-Down energy models, Bottom-Up energy models, Multi model comparative study, China Energy Modeling Forum (CEMF)

This paper researches constructive generalized synchronization (GS) for bidirectional continuous array of differential systems (BCADS). The results give general representations of GS in BCADS. The effectiveness of the theoretical results has been shown according numerical simulations.

The micellization behavior of two binary mixtures of an anionic sodium dodecylbenzene sulfonate with a nonionic surfactant octylphenol polyethoxylated ether (including OP-10 or OP-7) was investigated in aqueous solution at 298.15 K using the tensiometry, and the effect of hydrophilic chain of nonionic surfactant was discussed. In the framework of pseudophase separation model and based on the regular solution theory, the related micellization parameters and thermodynamic parameters were estimated by some models including Clint’s model, Rubingh’s model, etc. The two mixtures exist some differences in the micellization behavior. The synergistic effect, the antagonism, nonideal mixing and ideal mixing are observed in the two mixtures. The dependence of the mixed critical micelle concentration, the composition in mixed micelle, the interaction parameter between molecules on the composition in aqueous solution is explained by the electrostatic interaction, the steric effect and the shell structure of mixed micelle, etc. Thermodynamic parameters are adopted to account for the difference in energy and verify the micellization behavior. The two binary mixtures show different contributions of energy to the process of micellization. These findings help with understanding the nature on the interaction between two surfactants and the effect of the length of hydrophilic chain of nonionic surfactant so as to obtain some information in theoretical and practical investigations.

We calculate the electronic structures of Ge nanowires at the direct Γ-valley and indirect L-valley under the [100] direction uniaxial stress perpendicular to the nanowire axis using the effective-mass k.p theory, and the results demonstrate the stress along the [100] direction is effective to transform Ge nanowires from the indirect-band-gap to direct-band-gap semiconductor. Moreover, the optical gain and net peak gain under the [100] direction stress are also investigated, and it is interesting that the pure optical gain along the z direction can almost be obtained. Importantly, we find that the photon energy around 0.8 eV corresponding to the gain peak can be realized in Ge nanowires under an appropriate [100] direction stress when the diameter is in the range of 10∼20 nm, which means Ge nanowires can be engineered to be suitable for the telecom wavelength 1550 nm in the field of Si photonics via the [100] direction stress.

The interfacial and micellization behavior of binary mixture of an amino sulfonate amphoteric 3-(N-dodecyl ethylenediamino)-2-hydropropyl sulfonate (C12AS) and a cationic octadecyltrimethyl ammonium bromide (OTAB) were investigated in aqueous solution without or with a 70 g/L alcohol (including methanol, ethanol, 1-propanol and 1-butanol) at 313.15 K by both the tensiometry and the conductometry. The surface excess concentration, the minimum area per surfactant molecule at the saturated interface and the standard free energy of adsorption at the air-liquid interface were adopted to be characteristic of the interfacial adsorption monolayer. Based on the pseudophase separation model and the regular solution theory, the Clint’s model and the Rubingh’s model was used to obtain the related parameters including the interaction parameters between two surfactant molecules, the compositions and the activity coefficients in mixed micelle and thermodynamic parameters. The effect of the alcohol chain length on the interfacial adsorption and the mixed micellization was discussed. The addition of short chain alcohol influences the properties of mixed cosolvent, the conformation of C12AS molecule and the electrostatic interaction between two surfactant molecules. Thermodynamic data shows that the presence of alcohol with a longer chain is beneficial to form the adsorption monolayer and the mixed micelle, and also it depresses the contribution of entropy to the process of micellization. These findings help with understanding the mechanism on the effect of short chain alcohol on the interfacial and micellization behavior of binary surfactant mixtures and further designing the surfactant formulations.

As a new member of lead-free Na 0.5 Bi 0.5 TiO 3 (NBT) ceramics based on bismuth layer-structured ferroelectrics (BLSFs), Bi x Ti 3 O 6+1.5 x ( x = 3.96, 3.98, 4.0, 4.02, 4.04) ceramics was prepared by a conventional mixed oxide route. In order to explore the ferroelectric and dielectric properties, we changed the content of Bi in the ceramics. XRD patterns of Bi x Ti 3 O 6+1.5 x demonstrated that the new material was a single phase of Bi-layered perovskite structure. Through impedance spectra analysis, we found that the Bi 4.02 Ti 3 O 12.03 ceramics sintered at 1100 °C showed excellent dielectric properties with a highest dielectric constant of 8967.49 and a lowest dielectric loss of 0.00298 measured under 10 kHz, which were enhanced much compared with Bi 4 Ti 3 O 12 prepared by the same means. Meantime, the Curie temperature of the whole samples was about 670 °C. In addition, the ferroelectric hysteresis loops of all the samples indicated that they were ferroelectric materials, and Bi 4 Ti 3 O 12 ceramics sintered at 1100 °C processed a remanent polarization (2 P r ) of 12.206 µC/cm 2 and a coercive field of 29.542 kV/cm. SEM can roughly describe the results of the dielectric spectrum and ferroelectricity with different Bi concentration through grain size mechanics. Because of the high dielectric constant, wide operating temperature and low dielectric loss, the Bi 4 Ti 3 O 12 ceramics have a broad application prospect in components, such as sensors, high-temperature capacitors and so on.

In order to improve the antioxidant and antimicrobial abilities, hydroxamated degraded polysaccharides from Enteromorpha prolifera (HCDPE) were prepared from the corresponding carboxymethylated degraded polysaccharides (CDPE). HCDPE was characterized by FT-IR. The weight-average molecular weight of HCDPE was determined as 55.4 kDa. The in vitro antioxidant activity of HCDPE was evaluated by determining the radical (1,1-diphenyl-2-picrylhydrazyl (DPPH), hydroxyl and superoxide anion radicals) scavenging abilities and total antioxidant activity. It was found that DPPH radical scavenging ability and total antioxidant activity of HCDPE were significantly improved compared to those of CDPE. The inhibitory effects of polysaccharides against the five bacterial strains (Bacillus subtilis, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Salmonella spp.) were also evaluated by bacterial inhibition zone and minimum inhibitory concentration (MIC) assays. The results indicated that CDPE and HCDPE possess marked antimicrobial ability, while such an effect was not observed for the crude polysaccharides (PE) and the degraded polysaccharides (DPE).

The present study was designed to develop and validate a rapid, sensitive, and reliable ultra-high performance liquid chromatography coupled with tandem mass spectrometry (UHPLC-MS/MS) method for the simultaneous determination of five major active constituents in the traditional Chinese medicinal preparation Xingxiong injection (XXI) in rat plasma, including quercetin 3-O-rutinoside (QCR), kaempferol 3-O-rutinoside (KFR), isorhamnetin 3-O-rutinoside (ISR), bilobalide (BB), and ligustrazine (LGT). The plasma samples were pretreated by protein precipitation with acetonitrile. The chromatographic separation was achieved on a Waters Symmetry C18 analytical column (2.1 mm × 100 mm, 3.5 μm) with a mobile phase of 0.1% aqueous formic acid (A)-acetonitrile (B). Quantitation of the five bioactive constituents was achieved. Naringin was used as the internal standard (IS). All the calibration curves showed good linearity (r > 0.996) over the concentration range, with the lowest limit of quantification (LLOQ) between 2-18 ng·mL-1. The intra- and inter-day accuracy and precision of the analytes were both within acceptable limits. Moreover, satisfactory extraction recoveries (90.92%-104.03%) were obtained by protein precipitation. The validated method was successfully applied to a pharmacokinetic study of XXI in rats after intravenous administration at three doses. The pharmacokinetic parameters of the five compounds varied in a dose-dependent manner within the tested dosage range. The present study was the first report of pharmacokinetic study for XXI.

(Ce,Nd)-Fe-B sintered magnets were prepared by the addition of NdHx powders in Ce9Nd4.5Fe80B6.5 powders. The coercivity is rather low in Ce9Nd4.5Fe80B6.5 magnets, and Ce element prefers to distribute at the outer-layer of main phase (Ce,Nd)2Fe14B. The investigation of scanning electron microscope shows that the addition of NdHx powders leads to the increase of Nd content at grain outer-layer of main phase owing to the element diffusion. Magnetization reversal undergoes the nucleation of reversed domain wall at grain outer-later, and the addition of NdHx powders leads to the increase in the nucleation field of reversed domain, giving rise to the significant improvement of coercivity. The larger amount addition of NdHx powders leads to the increase in the amount of intergranular phase, resulting in the decreases of the remanence, the squareness of demagnetization curve and the maximum energy product.

The fracture toughness tests and a new miniature specimen technology named hydraulic bulge test (HBT) of 3Cr1Mo1/4V at four service time were carried out. Four J-R resistance curves by single-specimen method with one inch CT specimens were obtained to compute the JIC. Different definitions of equivalent fracture strain according to the section morphologies of HBT testing specimens were compared, and fracture energy of miniature specimens with three different thicknesses (0.4mm, 0.5mm and 0.6mm) were also calculated. Results showed that the typical HBT load-deflection curve can be divided into four sections like SPT curve. Equivalent fracture strain and fracture energy EHB can be chosen as two fracture parameters for the HBT specimen. Ductile fracture toughness JIC can be related approximately linearly to both the equivalent fracture strain and fracture energy EHB.

An enantioselective tandem Michael addition/ cyclization reaction between trisubstituted 2-nitro-1,3-enynes and cyclic 1,3-diketones catalyzed by a chiral organosquaramide catalyst in the presence of Ag2CO3 was developed. The chiral functionalized chromene products could be obtained in good yield and in 80-99% enantiomeric excess. The structures and absolute configurations of some of the products were confirmed by X-ray crystallographic analysis.

Directly extracting uranium from alkaline solution and seawater through an effective and economical method is still a challenging task. In this work, we for the first time propose a method of anionic exchange, based on a cationic MOF (metal-organic framework) adsorbent, namely Co-SLUG-35, to directly extract U(VI) from alkaline solution and seawater (South China Sea). The U(VI) adsorption experiments indicates that the EDS2− anions in Co-SLUG-35 can be completely replaced by U(VI) ions in an anionic manner, leading to an adsorption capability of 118 mg/g from alkaline U(VI) solution and excellent extraction efficiency of 1.05 mg/g from 1 L actual seawater in the concentration of 5.35 ppb. Most importantly, unlike other MOFs where degassing is primarily needed, however the use of present MOF need not any pretreatment. Moreover, ultrahigh selectivity towards U(VI) ions even over CrO42− and Cl− ions is also observed in Co-SLUG-35, suggesting its superior potential in extraction of uranium from seawater.

Carbon quantum dots (CQDs) reinforced polypyrrole nanowire (PPy-NW) was constructed via electrostatic self-assembly strategy. The as-made CQDs/PPy-NW composite demonstrated superior electrochemical properties benefited from a dotted line structure with large specific area, more active sites and outstanding electronic conductivity. As the results, the CQDs/PPy-NW composite electrode displayed a specific capacitance of 306 F g −1 at a current density of 0.5 A g −1 and retained 66.8% capacitance when the current density increased by 80 times (from 0.5 to 40 A g −1 ). In addition, the as-fabricated symmetric supercapacitor was able to offer a large areal capacitance (248.5 mF cm −2 at 0.2 mA cm −2 ) and good rate capability, the supercapacitor still retained good cycling stability even at a high current density of 5 mA cm −2 (85.2% capacitance retention after 5000 cycles). In conclusion, the good electrochemical properties suggest a great potential of the CQDs/PPy-NW in the development of high-performance supercapacitor electrode materials.

Recently, carbon quantum dots (CQDs) as a new zero-dimensional carbon nanomaterial have become a focus in electrochemical energy storage. In this paper, flexible all-solid-state supercapacitors (ASSSs) were electrochemically synthesized by on-step co-deposition of appropriate amounts of pyrrole monomer and CQDs in aqueous solution. The different electrodeposition time plays an important role in controlling morphologies of stainless steel wire meshes (SSWM)-supported CQDs/PPy composite film. The morphologies and compositions of the obtained CQDs/PPy composite electrodes were characterized by scanning electron microscope (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), Raman spectrum and X-ray photoelectron spectroscopy (XPS). Furthermore, a novel flexible ASSS device was fabricated using CQDs/PPy composite as the electrode and separated by polyvinyl alcohol/LiCl gel electrolyte. Benefiting from superior electrochemical properties of CQDs and PPy, the as-prepared CQDs/PPy composite ASSSs exhibit outstanding electrochemical performance with the areal capacitance 315 mF cm−2 (corresponding to specific capacitance of 308 F g−1) at a current density of 0.2 mA cm−2 and long cycle life with 85.7% capacitance retention after 2 000 cycles.

Mercury (Hg2+) ions have very high toxicity and widely spread as environmental pollutants. At present, many efforts have been taken to remove the hazardous materials of mercury(II) by adsorption, and it is highly desirable to develop a novel adsorbent with high adsorptive capacities. However it is still a big challenge to remove the ultra-low-concentration mercury ions from water. In this paper, MOF-74-Zn is explored for such function, showing high removal rate of Hg(II) from water without any pretreatment, especially for the ultra-trace Hg(II) ions in the ppb magnitude with the removal rate reaching to 54.48%, 69.71%, 72.26% when the initial concentration of Hg(II) is 20ppb, 40ppb, 50ppb, respectively.

A new compound, methylbergenin (1), was isolated from the whole plants of Ardisia japonica (Thunb.) Bl. (Myrsinaceae), along with eight known compounds: demethoxybergenin (2), bergenin (3), afzelin (4), quercitrin (5), bauerenol (6), bauerenone (7), α-spinasterol (8) and chondrillasterone (9). Compounds 1, 7 and 9 were isolated from A. japonica for the first time. The structure of compound 1 was determined on the basis of NMR (1D and 2D) and mass spectroscopic analysis. The absolute configuration of 1 was assessed by single-crystal X-ray diffraction. Compounds 1, 4, 5, 7 and 9 showed potential inhibitory effects against nitric oxide production in LPS stimulated RAW 264.7 murine macrophages. In addition, Compounds 7 and 9 exhibited cytotoxicity against A549 and HepG-2 cells.