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Silicon inverted pyramid (IP) structures, with lower reflectance and increased surface recombination, are one of the best choices for light-trapping structures of high-efficiency silicon solar cells. The solution process of IP generally goes through three main steps: porous silicon etched by metal-assisted chemical etching, acid etching, and alkali anisotropic etching. In this paper, the role that acid modification plays in IP preparation and the application of our optimized texture for passivated emitter and rear solar cells (PERC) were investigated. Experimental results show that acid plays a decisive role in optimizing and modifying the morphology of porous silicon; thus, the morphology of porous silicon has no direct influence on the morphology of IP. In addition, the opening size of IP is mainly determined by the size of silicon micron holes modified by the acid process. PC1D simulation results manifest that IPs can increase the short-circuit current density (Jsc) of devices by 1.04 mA/cm2 and power conversion efficiency by 0.55%; hence, our optimized IP-based PERC achieve the highest simulative conversion efficiency of 23.21%. This is an effective and important way to manipulate the structure of IP, which points out the direction of fabrication and application of high-efficiency IP textures.

Background and purpose: A high risk of brain injury has been reported with the usage of general anesthetics such as propofol in infants. Experimental data indicated that oxidative stress and inflammation are involved in the neurotoxicity induced by propofol. Febuxostat is a novel anti-gout agent recently reported to exert an anti-inflammatory effect. The present study aims to investigate the protective property of febuxostat against the cytotoxicity of propofol in brain endothelial cells as well as the underlying preliminary mechanism. Methods: The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was utilized to screen the optimized incubation concentration of febuxostat. bEnd.3 brain endothelial cells were stimulated with 2% propofol in the presence or absence of febuxostat (10, 20 μM) for 24 h. The lactate dehydrogenase (LDH) release assay was conducted to detect cytotoxicity. The reactive oxygen species (ROS) levels were evaluated using dichloro-dihydro-fluorescein diacetate (DCFH-DA) staining, and the concentration of reduced glutathione (GSH) was determined using a commercial kit. The expressions of TNF-α, IL-6, IL-12, CXCL-1, PDPN, CXCL8, VCAM-1, and E-selectin were determined using a quantitative real-time polymerase chain reaction (qRT-PCR) and an enzyme-linked immunosorbent assay (ELISA). Western blot and qRT-PCR were utilized to determine the expressions of COX-2 and KLF6. The production of PGE2 was evaluated by ELISA. Results: First, increased LDH release induced by propofol was significantly suppressed by febuxostat. The oxidative stress (elevated ROS levels and decreased GSH level) induced by propofol was alleviated by febuxostat. Second, the upregulated inflammatory factors (TNF-α, IL-6, and IL-12), pro-inflammatory chemokines (CXCL-1, PDPN, and CXCL8), adhesion molecules (VCAM-1 and E-selectin), and inflammatory mediators (COX-2 and PGE2) induced by propofol were greatly downregulated by febuxostat. Lastly, the expression of KLF6 was significantly suppressed by propofol but greatly elevated by febuxostat. Conclusion: Febuxostat prevented the cytotoxicity of propofol in brain endothelial cells by alleviating oxidative stress and inflammatory response through KLF6.

Inulin as a commercial prebiotic could selectively promote the growth of beneficial gut microbes such as lactic acid bacteria (LAB). Whether LAB in rabbit gut possesses the capability to metabolize and utilize inulin is little known. Therefore, this study recovered 94 LAB strains from neonate rabbits and found that only 29% (28/94) could metabolize inulin with both species- and strain-specificity. The most vigorous inulin-degrading strain, Lacticaseibacillus paracasei YT170, could efficiently utilize both short-chain and long-chain components through thin-layer chromatography analysis. From genomic analysis, a predicted fosRABCDXE operon encoding putative cell wall-anchored fructan β-fructosidase, five fructose-transporting proteins and a pts1BCA operon encoding putative β-fructofuranosidase and sucrose-specific IIBCA components were linked to long-chain and short-chain inulin utilization respectively. This study provides a mechanistic rationale for effect of inulin administration on rabbits and lays a foundation for synbiotic applications aimed at modulating the intestinal microbiota of young rabbits.

Recently, surface with desirable gradients has been proved to be a powerful tool for diverse applications from biological systems and chemical analysis to material science. In this work, we demonstrate a versatile and universal approach to realize controllable physicochemical properties in orthogonal gradients on polydimethylsiloxane (PDMS) surface. Based on a novel microfluidics network, we can easily establish the concentration gradients within the microfluidic channel for surface polymerization or chemical deposition to realize the stable characteristic gradient on the PDMS substrate. The method was introduced to prepare surface with two-dimensional physical (roughness) gradients, or combinational physicochemical gradients to study the synergistic effect on interested phenomenon. As a proof of concept, the experimental results show that the as-prepared substrate can effectively influence in various fields, such as protein adsorption and nano-particle immobilization, which can potentially be used for future systematical study in biological systems or practical applications in bio/chemical analysis/sensing.

As a coordination polymer built of [Mo3S13]2- clusters, amorphous nanoscale MoSx (a-MoSx) is an attractive electrocatalyst for the hydrogen evolution reaction (HER) due to its abundant active sites and scalable synthesis. However, clarifying the internal catalytic mechanism and achieving even higher HER performance with scalable size are still challenging. Herein, a new hybrid catalyst of a-MoSx flakes decorated with Ni3S2 nanocrystals (size < 10 nm) has been successfully synthesized on 10 × 20 cm2-sized Ni foam by a portable hydrothermal route. As the strong interaction of [Mo3S13]2- clusters with Ni3S2 is evidenced by comprehensive binding state and Raman characterization, the polymerization effect of [Mo3S13]2- itself and the perfect interfaces between [Mo3S13]2- clusters and Ni3S2 are also confirmed by density functional theory calculations. These two factors greatly lower the absorption energy of hydrogen nearly to zero, leading to much improved HER activity. Current densities of 100 and 600 mA cm-2 are achieved at overpotentials of 181 and 246 mV, respectively, which are so far the highest values approaching practical applications. The findings of this work provide a fundamental reference about the catalytic origin of a-MoSx based catalysts, and shed light on the practical applications of non-precious electrocatalysts for their compatibility with low cost batch production.

In this work, we demonstrate the synthesis of a composite architecture that is composed of nitrogen-doped carbon encapsulating cobalt and titanium nitride nanoparticles on carbon cloth (Co–TiN@NG-x/CC) for hydrogen evolution reaction and supercapacitor applications. The optimized electrocatalyst, Co–TiN@NG-2/CC, shows a low overpotential of ∼208 mV to drive a current density of 10 mA cm−2 and long-term durability in 1 M KOH. For the supercapacitor (SC), Co–TiN@NG-2/CC exhibits a capacitance of up to 189 mF cm−2 at a current density of 0.5 mA cm−2 and good rate capability. The capacitance can retain ca. 70% of the initial specific capacitance even after 1000 cycles at a current density of 1 mA cm−2. The enhanced hydrogen evolution reaction and supercapacitance are attributed to the synergistic effect between titanium nitride and Co nanoparticles in the N-doped carbon matrix, leading to increased active sites and electrical conductivity.

A simple, rapid, and reliable method was developed for the direct determination of four high field strength elements (HFSEs, namely, Nb, Ta, Zr, and Hf) in refractory silicate rocks using slurry nebulisation inductively coupled plasma mass spectrometry (ICP-MS). Samples were dispersed in a 0.2% Triton X-100 solution by wet-grinding with a tissue cell-destroyer, and 90% of the particles in the slurry were found to be less than 1.5 μm in diameter during 90 s of milling. Fine slurry was directly introduced into ICP and detected by mass spectrometry. The behaviors of different particle size distributions in the transportation and ionisation processes were investigated. Results indicated that the cut-off size for particle efficient transport (in the sample introduction system) and complete ionization (in the ICP) was approximately 8 μm and 4 μm, respectively. Our fine slurries (mean particle size

Aiming at the development of a controlled redox responsive polymeric micelle system, a series of redox-sensitive ABA triblock degradable copolymers with different amounts of disulfide bonds were synthesized. These multi-disulfide-containing amphiphilic copolymers are able to self-assemble in aqueous solution to form spherical micelles with a hydrophobic polyurethane block forming the hydrophobic core. The presence of dynamic and labile disulfide bonds in the copolymer makes the copolymer and its micelle have responsivity to stimuli such as redox agents and ultrasound. The micellar properties and release kinetics of encapsulated guest molecules in response to stimuli were investigated using hydrophobic pyrene as a fluorescent probe and DTT as a redox agent. The redox-responsive behavior could be adjusted by changing the amount of disulfide bonds within the copolymer backbone. A relatively fast release behavior was observed for micelles formed by the copolymers in which every repeat unit of the hydrophobic block contains a disulfide bond. Furthermore, the release rate could be greatly enhanced and adjusted remotely under HIFU irradiation in the presence of DTT. The HIFU/redox combined stimulus for the specially designed copolymer micelles containing disulfide bonds provides a novel modality for drug delivery systems.

Magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS) have tremendous utility in many fields, such as clinical diagnosis, medical research and brain science. MRI provides high resolution anatomic images of tissues/organs, and MRS provides functional molecular information related to specific regions of tissues/organs. However, it is often difficult for conventional MRI/MRS to selectively image/probe a specific metabolite molecule other than water and fat. This greatly limits study of the molecular mechanisms underlying metabolism and disease. Herein, we report a novel method for obtaining an exact molecularly targeted MRI and MRS. This method uses the nuclear spin singlet state to select the signals from a specific molecule. Several endogenous molecules in living organism such as N-acetylaspartate and dopamine have been exemplarily imaged and probed as the targeted molecules in the MRI and MRS experiments, demonstrating the unique molecular selectivity of the developed method.Endogenous-molecule-targeted MRI and MRS can be achieved by using the new pulse sequences

Achievement of improved structural stability and conductivity for Mn-based oxides is the crucial premise for them to be high-performance anodes of lithium-ion batteries due to their large volume effect and poor intrinsic conductivity. Herein, the lithium storage performance of the MnxOy nanoparticles containing dominant MnO and slight MnO2 and Mn3O4 has been significantly improved by embedding them into a CNT supporting porous carbon. This composite is therefore denoted as CNT/MnxOy/C. The comparison results of the electrochemical performance of thus CNT/MnxOy/C with CNT/Mn3O4 and pure Mn3O4 nanoparticles demonstrate that the well-designed synergistic effect of high conductive CNT support and flexible spongy porous carbon is responsible for its improved performance, which efficiently enhances not only the structural stability but also the electrochemical kinetics of the CNT/MnxOy/C. As a result, this CNT/MnxOy/C anode shows outstanding performance, obtaining high capacities of 936.5 and 410.5 mAh g-1 at 200 and 1000 mA g-1 after 260 and 800 cycles, respectively. Moreover, this strategy proposed here will be hopefully instructive in constructing other advanced metal oxide nanomaterials toward improved performance of lithium-ion battery anodes.

Sichuan pickle is a natural combination of probiotics and dietary fibers, in which a strain Lactiplantibacillus plantarum QS7T was found to be capable of efficiently metabolizing inulin. However, the underlying molecular mechanism of inulin consumption by the strain QS7T is unclear. Therefore, this study firstly investigated the metabolic characteristics of inulin in the strain QS7T, and the results showed it could grow very well on the medium containing inulin as a carbon source (maximum OD600 nm, 1.891 ± 0.028) and degrade both short-chain oligofructose and long-chain fructan components through thin layer chromatography analysis. Genomic sequencing and analysis revealed a high percentage of functional genes associated with carbohydrate transport and metabolism, particularly glycoside hydrolase (GH) genes responsible for hydrolysing carbohydrates, within the genome of the strain QS7T. Furthermore, comparative transcriptomic analysis of L. plantarum QS7T in response to inulin or glucose indicated that functional genes associated with inulin consumption including several genes encoding PTS sugar transporters and two predicted GH32 family genes encoding beta-fructofuranosidase and beta-fructosidase were significantly up-regulated by inulin compared to the gene expression on glucose. In conclusion, we obtained a mechanistic understanding of interplay between probiotic L. plantarum QS7T derived from Sichuan pickle and natural dietary fiber, inulin; totally two operons including a sacPTS1 operon responsible for metabolizing short-chain oligofructose primarily in the cytoplasm and a fos operon responsible for extracellularly degrading all moderate and long-chain fructan components linked to inulin consumption by L. plantarum QS7T.

Swift and convenient handling of discrete micro-droplets on digital microfluidics platform has recently attracted plentiful interest in high-throughput bio/chemical analysis. In this work, we developed a novel and facile approach to manipulate the micro-droplet based on a hydrophobic and low-adhesive magnetically functionalized polydimethylsiloxane (MF-PDMS) membrane. The platform is composed of the MF-PDMS membrane as the substrate, integrated with non-magnetic PDMS micro-pillar arrays on-top to ensure the low adhesion between the platform and the resident drops. With applied magnetic field, the localized membrane deformation could induce the unbalanced force imposed on the micro-droplet, leading to free rolling-off for flexible control including the position and velocity, etc. We have experimentally verified that the proposed avenue could be successfully applied for kinds of on-chip micro-droplet manipulations, such as droplet merging, parallel manipulation, flexible trajectory control. With the flexibility and maximum velocity reported herein (~ 79 ± 6 mm/s), we believe that the presented platform could be potentially applied for biological or chemical analysis where precise manipulation of large amounts of individual droplets is critical.

A new kind of fast near-infrared (NIR) light-responsive shape-memory polymer composites was prepared by introducing polydopamine particles (PDAPs) into commercial shape-memory polyurethane (SMPU). The toughness and strength of the polydopamine-particle-filled polyurethane composites (SMPU-PDAPs) were significantly enhanced with the addition of PDAPs due to the strong interface interaction between PDAPs and polyurethane segments. Owing to the outstanding photothermal effect of PDAPs, the composites exhibit a rapid light-responsive shape-memory process in 60 s with a PDAPs content of 0.01 wt%. Due to the excellent dispersion and convenient preparation method, PDAPs have great potential to be used as high-efficiency and environmentally friendly fillers to obtain novel photoactive functional polymer composites.

Background Patients with coronary artery disease (CAD) are often asymptomatic and their condition can go largely untreated, resulting in severe outcomes. Therefore, there is an urgent need for new biomarkers of CAD. Methods In this cross-sectional study, 540 patients were recruited. We performed a preliminary study, which included nine CAD-positive and nine CAD-negative patients, wherein the biomarker NCAM-1 was identified using label-free mass spectrometry. We then validated the efficacy of NCAM-1 in 429 CAD-positive and 93 CAD-negative patients. Results In the preliminary study, we found 204 different proteins in the two groups, of which seven were found in all samples; from these, we decided to explore the use of neural cell adhesion molecule (NCAM)-1 as a biomarker for CAD. We found NCAM-1 levels to be 53.22ng/ml lower in CAD patients (161.76±105.50ng/ml) than in control samples (214.98±146.55ng/ml; p=0.0011). Spearman correlation analysis showed NCAM-1 was significantly correlated with Troponin T (cTnT), and N-terminal B-type natriuretic peptide (NT-proBNP) in CAD-positive patients, and with homocysteine in CAD-negative controls. Moreover, in multivariable logistic regression analysis, decreased plasma NCAM-1 was significantly associated with increased risk of CAD (multivariable-adjusted odds ratios: 0.728; 95% confidence interval, 0.599–0.884, p=0.001), adjusting for age, gender, current smoking status, cholesterol, triglyceride, glucose, creatine, homocysteine, cTnT, and NT-proBNP. Conclusions These findings suggested that NCAM-1 may be a potential biomarker of CAD.

Flexible and wearable supercapacitors (SCs) have received extensive attention due to their promising applications in wearable electronics. Previous efforts have been mainly devoted to fabricate electrode materials with high surface areas, including activated carbon through carbonizing natural fibers at high temperature. This methodology however frequently disintegrates the fibrous structures and fails to take full advantage of the intrinsic and foremost feature of the fibers as fabrics. Herein we proposed one alternative strategy to enhance SC performance through utilizing natural hollow Calotropis gigantea fibers (CGFs) with hydrophobic surfaces to confine conductive polymer of polypyrrole (PPy) both outside and inside of the fiber lumen. The in situ electrodeposited PPy enabled a full contact between the electrode material and electrolyte, enlarged the electrolyte accessible area and spurred the capacitive performance of the SC, which demonstrated a significantly improved specific capacitance of 785.78 mF cm−2 at a current density of 4 mA cm −2 compared with the 648.44 mF cm−2 of SCs without the fibers (a 21.2% increase). The harness of confinement effect could potentially expand to be a general way to rationally design synthetic fibers with customized inner and outer diameter ratios, superficial hydrophobic/hydrophilic properties to realize optimum electrochemical performance for SCs.

Active catalysts for nitrogen fixation (N2-fixation) have been widely pursued through constant efforts for industrial applications. Here, we report a family of catalysts, MXenes (M2X: M = Mo, Ta, Ti, and W; X = C and N), for application in N2-fixation based on density functional theory calculations. We find that the catalytic performance of MXenes strongly depends on the reaction energy in each reaction step. More exothermic steps lead to higher catalytic performance in the course of N2-fixation. We show that the reaction energy in N2-fixation is strongly affected by the charge transfer: (1) if N atoms gain more electrons in a step, the reaction is exothermic with a larger reaction energy; (2) if N atoms lose electrons in a step, the reaction is endothermic in general. We further show that Mo2C and W2C are highly active for N2-fixation due to their exothermic reactions and strong charge transfer, which may be applicable in the chemical-engineering industry.

Herein, it is demonstrated that the lithium storage performance of Cu2O electrode has been significantly upgraded by fabricating embedment of porous carbon (PC) with carbon nanotube (CNT) scaffold successfully. It is found that the combined effect of high conductive CNT and flexibly spongy porous carbon plays critical role in improving the electrochemical performance of Cu2O electrode for lithium-ion batteries, which efficiently upgrades not only the structural stability but also the conductivity of whole electrode. As a result, this Cu2O-based composite electrode shows outstanding cycling performance, high capacity and good rate capability, therefore exhibiting good promising for advanced lithium-ion battery anodes.

A novel facile method for the detection of the phosphodiesterase type 5 enzyme inhibitors added illegally into health products was established using thin-layer chromatography and surface enhanced Raman spectroscopy combined with BP neural network. When the detecting conditions were optimized in detail, a repetitive adding procedure of silver colloids with the total amount keeping constant was used to improve the enhancement effect of surface enhanced Raman spectroscopy. According to the main Raman peaks and the retention factor of analyte, the data predictive model was established. Under the optimized experimental conditions, this method was successful to apply to detect the artificially produced model samples, and the limit of detection less than 5 mg/kg was obtained. Base on the better sensitivity of this method, the real samples have been detected accurately and the detection results were confirmed by high-performance liquid chromatography. In addition, the developed method was suitable for the detection of other adulterants, especially those that have similar chromatographic or spectroscopic behaviors. This article is protected by copyright. All rights reserved

Using TiO2 nanorods as one-dimensional (1D) electron transport tunnel, BiVO4 as light harvester, and Co-Pi (Cobalt-Phosphate) as co-catalyst, TiO2/BiVO4/Co-Pi nanorod arrays were fabricated as efficient photoanode on a FTO substrate for photoelectrochemical (PEC) water splitting cells. It was found that the monoclinic BiVO4 nanoflakes were mainly vertically attached to the side faces of rutile TiO2 nanorods with an average size of ∼35 nm and a selective growth direction along . By changing the electrodeposited quantity of BiVO4, the effect of the loading density of BiVO4 on the PEC performance was systematically studied, and an optimum photocurrent of ∼1.86 mA cm−2 at 1.0 VRHE with an onset potential as small as 0.3 VRHE and IPCE of 26% (at 450 nm) was obtained for the TiO2/BiVO4/Co-Pi anodes. Electrochemical impedance spectroscopy showed that Co-Pi can greatly decrease the charge transfer resistance at the photoanode/electrolyte interface. Along with the band alignment of the 1D nanoarray heterostructure beneficial for the charge separation, a hydrogen production of ∼7.31 μmol cm−2 h−1 was achieved for the efficient water splitting system. Such a heterostructured 1D nanoarray configuration can be extended to other PEC water splitting systems as well to increase the number of reactive sites and absorption of solar light, and to enhance the OER kinetics.

A reliable upconversion (UC) material assembled from Au@Ag (UC@SiO2@Au@Ag), as the substrate, was firstly employed to detect hexamethylenetetramine (HMT) in bean vermicelli by surface enhanced Raman spectroscopy (SERS). In this substrate, UC can convert near-infrared (NIR) light into visible light to promote localized surface plasmon resonance (LSPR) of noble metal nanoparticles to enhance the SERS signal. According to optimized synthesis conditions, the SERS substrate was obtained and evaluated. The substrate shows uniformity with RSD of 7.05% and 7.37% for the Raman vibrations at ∼780 cm−1 and ∼1043 cm−1 respectively, and sensitivity with detection limits of 1 mg L−1 for HMT. Based on the better sensitivity of this method, the artificially positive samples have been detected.

In this paper, a comprehensive method for the identification of the unknown halogenated DBPs (X-DBPs, X = Cl, Br, and I) in the tap water of Wuhan, China via liquid chromatography-high resolution mass spectrometry (LC-HRMS) was developed. 123 X-DBPs were identified through the stepwise procedure, 94 of them were newly identified, and 3 of them were confirmed by standards. Most X-DBPs were aliphatic compounds and highly unsaturated and phenolic compounds, some X-DBPs contained multiple halogen atoms and rich in carboxyl groups, such as C2H2O2BrCl, C2H2O2Br2, and C2H2O2ClI. It was worth noting that the concentration of some X-DBPs had the same trend with time. Most Cl-DBPs remained stable and I-DBPs were detected occasionally by monitoring the change of concentration of these X-DPBs with the time during three consecutive months. The results demonstrate that the proposed method could provide valuable molecular formula and structure information on unknown multiple halogenated DBPs, or be used for the identification of other multiple halogenated organic compounds in different media.

Hydrogen evolution reaction (HER) is a vital step for electrochemical energy conversion technologies. However, developing cost-efficient electrocatalysts remains a huge challenge. Here, we report that Cr-doped NiSx (Cr-NiSx) in situ grown on Ni foam via a hydrothermal sulfurization reaction can be an ultra-highly efficient and low-cost electrocatalyst for HER in alkaline condition. We find that the Cr-doping can trigger the formation of NiS and NiS1.19, leading to the suppression of Ni3S2 in the nanostructure. We show that Cr-NiSx exhibits an excellent HER activity with an ultralow overpotential of 81 mV at 10 mA cm−2, better than those of most nickel sulfide catalysts, and good stability. Our combined experimental and computational study reveals that the excellent performance is contributed by: (1) stabilized NiSx phase, (2) strongly improved conductivity, (3) greatly enhanced active sites, and (4) reduced Gibbs free energy for hydrogen adsorption (ΔGH) due to the Cr-doping. We believe that this work provides a simple approach to design cost-effective and ultra-highly efficient HER electrocatalysts for practical applications.

Background Calcium (water) density (DCa(Wa)) of gemstone spectral imaging by spectral computed tomography (CT) is a new method of evaluating bone structures. Purpose To investigate age-related change of DCa(Wa) of a chosen lumbar vertebra in adult women with spectral CT and the correlation between the DCa(Wa) and bone mineral density (BMD) of dual-energy X-ray absorptiometry (DXA). Material and Methods A total of 305 adult women underwent spectral CT, 127 of whom simultaneously underwent DXA. All the patients were divided into 11 subgroups based on age. DCa(Wa) and BMD were measured at the second lumbar vertebra on the calcium (water)-based material decomposition images of spectral CT and DXA, respectively. A one-way analysis of variance (ANOVA) was performed for the difference of the measurements among adjacent age subgroups. Pearson correlation was used to assess the association between age and DCa(Wa), age and BMD, as well as DCa(Wa) and BMD. Results There was a significant negative correlation between DCa(Wa) and age (r = −0.719) as well as BMD and age(r = −0.851). The mean DCa(Wa) of L2 vertebral body was significantly different between the 40–44- and 45–49-, 45–49- and 50–54-, 55–59- and 60–64-, 65–69- and 70–74-year-old age subgroups. BMD was significantly different between the 35–39- and 40–44-, 45–49- and 50–54-, and 65–69- and 70–74-year-old age subgroups. There was a significant positive correlation between DCa(Wa) and BMD. Conclusions The DCa(Wa) of lumbar vertebra by spectral CT demonstrated similar age distribution as BMD of DXA and could be used as a method of measuring the vertebral bone mineral density in adult women.

Novel conjugated microporous frameworks based on adamantane (CMF-Ads) have been successfully synthesized under mild conditions. Eight-arm tetraphenyl “knots” and a conjugated π-electron skeleton endowed the target CMF-Ads with ultra-high thermal stability (up to 500 °C), high surface area (up to 907 m2 g−1), excellent CO2 uptake capacity of 15.13 wt % at 273 K and 1 bar, as well as superior organic vapor (benzene, hexane) adsorption. The ultra-high gas uptake capacity and selectivity of these CMF-Ads herein exceeds most conjugated microporous frameworks reported to date, highlighting their potential as materials for clean energy application.

Enhancing drug loading efficacy and stability of polymeric micelles remains a grand challenge. Here we develop adamantane-based star copolymers adamantane-[poly(ε-caprolactone)-b-poly(2-(diethylamino)ethyl methacrylate)-b-poly(poly(ethylene glycol) methyl ether methacrylate)]4 (Ad-(PCL-b-PDEAEMA-b-PPEGMA)4) and their self-assembled micelles for controlled drug delivery. Results show that the polymers have excellent stability in solution with low critical micelle concentration (CMC) (0.0025–0.0034 mg/mL) and the apparent base dissociation constant (pKb) of the polymers is from 5.31 to 6.05. Dynamic light scattering analysis exhibits the great environmental response capability of the pH-sensitive micelles according to particle sizes and zeta potentials. With the synergy effect of the adamantane and hydrophobic block, the micelles display the high Doxorubicin (DOX) loading efficacy (up to 22.4%). The DOX release study shows that the micelles are capable of controlled release for drug. This work indicates the Ad-(PCL-b-PDEAEMA-b-PPEGMA)4 micelles may provide new guidelines for drug control and release system in overcoming cancer treatment.

Er3+/Yb3+ codoped tellurite-zinc-niobium (TZNb) glass was prepared by the melt-quenching method and used for the construction of a point all-fiber temperature sensor. The glass thermal stability and network structural properties were studied by differential thermal analysis and Raman spectrum, respectively. High glass transition temperature is beneficial to widen the working temperature range. The dependence of fluorescence intensity ratio (FIR) of green upconversion emissions on the surrounding temperature from 276 to 363 K was experimentally investigated and the maximum temperature sensitivity is 95 × 10−4 K−1 at 363 K. Strong green upconversion emission, broad temperature measurement range and high sensitivity indicate this point temperature sensor is a promising optical device for application on optical temperature sensing.

The metal-supramolecular diblock copolymer containing mechano-labile bis(terpyridine)-Cu(II) complex linkage in the junction point was synthesized. These metal-ligand containing amphiphilic copolymers are able to self-assemble in aqueous solution to form spherical micelles with poly(propylene glycol) block forming the hydrophobic core. It is found that high intensity focused ultrasound can open the copolymer micelles and trigger the release of the payload in the micelle. The micellar properties and release kinetics of encapsulated guest molecule in response to ultrasound stimuli were investigated. The weak Cu(II)-terpyridine dynamic bond in the copolymer chain can be cleaved under ultrasound and thus leads to the disruption of the copolymer micelle and the release of loaded cargo. This study will open up a new way for the molecular design of ultrasound modulated drug delivery systems.

A big challenge in developing stimuli-responsive materials is to integrate multiple functionalities such as shape memory property, healable ability, recyclability into a single-component material. With this purpose, we designed a novel poly(n-butyl acrylate-co-methyl methacrylate) bearing a side group 2,6-bis(1′-methylbenzimidazolyl)pyridine ligand, which is dynamically crosslinked by the metal salt zinc trifluoromethanesulfonate to obtain the metallosupramolecular polymer. The shape recovery and healing is achieved upon application of a thermal or light stimulus due to the specific metal–ligand interactions which not only serve as an “inert” crosslink network at low temperature to produce the shape recovery, but also dissociate at high temperature for healing. The healing rate is quick and the healing efficiently is close to ∼90%.

The synthesis of multi-functional nanocarriers and the design of new stimuli-responsive means are equally important for drug delivery. Ultrasound can be used as a remote, non-invasive and controllable trigger for the stimuli-responsive release of nanocarriers. Polymeric micelles are one kind of potential drug nanocarrier. By combining ultrasound and polymeric micelles, a new modality (i.e., ultrasound-mediated polymeric micelle drug delivery) has been developed and has recently received increasing attention. A major challenge remaining in developing ultrasound-responsive polymeric micelles is the improvement of the sensitivity or responsiveness of polymeric micelles to ultrasound. This chapter reviews the recent advance in this field. In order to understand the interaction mechanism between ultrasound stimulus and polymeric micelles, ultrasound effects, such as thermal effect, cavitation effect, ultrasound sonochemistry (including ultrasonic degradation, ultrasound-initiated polymerization, ultrasonic in-situ polymerization and ultrasound site-specific degradation), as well as basic micellar knowledge are introduced. Ultrasound-mediated polymeric micelle drug delivery has been classified into two main streams based on the different interaction mechanism between ultrasound and polymeric micelles; one is based on the ultrasound-induced physical disruption of the micelle and reversible release of payload. The other is based on micellar ultrasound mechanochemical disruption and irreversible release of payload.

Crude protein, total lipids, moisture, total ashes and selected mineral (Ca, Mg, Fe, Zn, Cu, Mn) content, fatty acid and amino acid composition were determined in the muscle tissue of three widely consumed fish species (sardine, anchovy and mackerel) obtained from Quanzhou of China. All fish species were high in protein (21.46%~22.75%), with total lipid and moisture content varied from 2.24% to 8.23% and from 69.7% to 74.9%, respectively, depending on the species. Total ash content range from 1.25%~1.63% but macrominerals content varied considerably with Mg content ranged from 470.24mg/100g to 687.45mg/100g and Ca levels ranged from 16.40mg/100g~109.22 mg/100g depending on the species. The most abundant microminerals were Fe and Zn followed by Cu and Mn. In all the three species, palmitic acid (28.44%~30.62%) was the predominant saturated fatty acid. Oleic acid (11.23%~22.15%) was the most abundant monounsaturated fatty acid. DHA was the main polyunsaturated fatty acids, followed by EPA. Sardine had the highest DHA (12.74%). Amino acid compositions were similar for the three species which were high in glutamate, lysine, leucine and aspartate and low in cysteine. Almost all amino acids content of anchovy were higher than other two species.

The juvenile Chinese mitten crabs Eriocheir sinensis (1.40 ± 0.43 g) were cultured in water of 5.34 ± 0.43 (hypoxia, treatment group) and 21.02 ± 0.06 kPa (high dissolved oxygen (DO), control group) DO for 24 h, respectively. The total hemocyte counts (THC), the hyaline hemocyte counts were measured at 0 and 24 h in the treatment group, and superoxide dismutase (SOD) activity, concentrations of lactic acid and hemocyanin (Hc) in hemolymph and the metabolism of hepatopancreas (concentrations of glucose, total cholesterol, uric acid, total protein, urea, triglyceride in hepatopancreas) were assayed at 0, 2, 8, and 24 h in both treatment and control groups. The hyaline hemocyte counts and THC decreased significantly by 66 and 49% after exposure to hypoxic water for 24 h, respectively. SOD activity, Hc and lactic acid content were significantly affected in treatment group, and there were significant differences between treatment and control groups. In the treatment group, the concentration of glucose, cholesterol and uric acid in hepatopancreas had a significant variation for 24 h. The concentration of total protein, urea and triglyceride between treatment and control groups was not significantly different after 0, 2, 8, 24 h. However, there were significant differences between treatment and control groups in terms of total protein, glucose, and uric acid concentration. Taken together, the effect of hypoxia is comprehensive in juvenile Chinese mitten crab Eriocheir sinensis.

This study was conducted to develop a method for improving tenderness and inhibiting oxidative change of yak meat by ginger extract (GE) treatment. Uniform-sized 3 cm × 3 cm × 3 cm yak meat chunks (Longissimus dorsi muscles) were marinated with distilled water, 3%, 5%, 7% GE and 0.2% sodium ascorbate, respectively. The samples stored for 24 h, 48 h and 72 h, and 3, 5, 7, 9 and 11 days at 4C ± 1C. The shear force values and cooking yield of the GE-treated samples were compared with that of the control groups, and thiobarbituric acid reactive substance (TBARS) value was compared with both the control group and the 0.2% sodium ascorbate-treated group. Significantly lower shear force values and TBARS value (P

Aromatic isothiocyanates are interesting pseudohalides molecules which are widely existed in healthy intact plants. However, few attempts were made to analyze their structures and correlate their electronic structure with other properties (e.g., chemical reactivity). In this paper, the electronic structures and substituent effects of o-, m-, and p- iodophenyl isothiocyanates were studied by the ultraviolet photoelectron spectroscopy and discussed through the careful analysis of ionization potentials corresponding toand n orbitals. Owing to the effects of the iodine atom and the NCS group, the first ionization potentials of iodophenyl isothiocyanates are lower than that of iodobenzene and phenyl isothio- cyanate. And the energetic order of the first six MOs is � 3 > � 2 > nS > n� > � NCS > n�. The energy and electron density of the topmost occupied molecular orbitals of iodophenyl isothiocyanates were analyzed. It has been found that the ioniza- tion energy ofNCS orbital electrons in p-iodophenyl isothiocyanate is the lowest of the three iodophenyl isothiocyanates, which indicates the chemical reactivity of p-iodophenyl isothiocyanate is the highest.

Linear Polystyrene (PS) was grafted onto the convex surfaces of multiwalled carbon nanotubes (MWCNTs). Bromine-terminated polystyrene synthesized by atom transfer radical polymerization (ATRP) was directly reacted with MWCNTs under ATRP conditions using CuBr/2,2′-bipyridine as catalyst. The PS-grafted MWCNT samples were characterized by scanning electron microscopy, transmission electron microscopy, FT-IR spectra, Raman spectra, 1H NMR, UV–vis spectra, thermal gravimetric analyses, and X-ray diffraction. The products can dissolve in organic solvents such as 1,2-dichlorobenzene, tetrahydrofuran and chloroform to form well-dispersed solutions. Optical limiting property measurements in chloroform were carried out at 532 nm using the open-aperture z-scan technique. The results demonstrate that the samples preserve good optical limiting properties when the polymer is covalently attached to the carbon nanotube.

The electronic structure and the dissociative ionization of selenium oxychloride, OSeCl2, have been investigated in the valence region by using results from both photoelectron spectroscopy (PES) and synchrotron-based photoelectron photoion coincidence (PEPICO) spectra. The PES is assigned with the help of quantum chemical calculations at the outer-valence Green's function (OVGF) and symmetry adapted cluster/configuration interaction (SAC-CI) levels. The first energy ionization is observed at 11.47 eV assigned to the ionization of electrons formally delocalized over the Se, Cl, and O lone pair orbitals. Irradiation of OSeCl2 with photons in the valence region leads to the formation of OSeCl2•+, OSeCl+, SeCl2•+, SeCl+, and SeO•+ ions. Furthermore, the inner shell Se 3p, Cl 2p, and Se 3s electronic regions of OSeCl2 together with S 2p, Cl 2p, and S 2s electronic regions of thionyl chloride, OSCl2, have been studied by using tunable synchrotron radiation. Thus, total ion yield spectra and the fragmentation patterns deduced from PEPICO spectra at the various excitation energies have been studied. Cl+, O•+, and Se•+ ions appear as the most intense fragments in the OSeCl2 PEPICO spectra, like in the sulfur analogue OSCl2, whose photofragmentation is dominated by the Cl+, O•+, and S•+ ions. Fragmentation processes in OSCl2 leading to the formation of the double coincidences involving atomic ions appear as the most intense in the PEPIPICO spectra. (Figure Presented). Fil: Gerones, Mariana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Química Inorgánica ; Argentina Fil: Rodriguez Pirani, Lucas Sebastian. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Química Inorgánica ; Argentina Fil: Erben, Mauricio Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Química Inorgánica ; Argentina Fil: Romano, Rosana Mariel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Química Inorgánica ; Argentina Fil: Cavasso Filho, Reinaldo L.. Universidade Federal do ABC; Brasil Fil: Tong, Sheng Rui. Chinese Academy of Sciences; República de China Fil: Ge, Maofa. Chinese Academy of Sciences; República de China Fil: Della Védova, Carlos Omar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Química Inorgánica ; Argentina

The nonlinear optical properties and the ultrafast dynamics for the polymers with the donor–acceptor structure were measured by the femtosecond laser spectroscopic techniques. Two polymers show intense two-photon absorption properties due to the unique tribranched structure. The ultrafast dynamics of the excited states were measured by two-color femtosecond pump–probe method, and the relaxation properties of the fluorescence emission state were detected by time-resolved fluorescence (TRFL) technique. We suggest that the fast decay component in the TRFL dynamics comes from the exciton migration process, and the slow decay component is caused by the recombination process of the excitons. In two-color femtosecond pump–probe and TRFL dynamics, both decay processes were accelerated when the solvent was changed from CHCl 3 to DMSO, due to the fact that the dipole moment of DMSO is larger than that of CHCl 3 .

Fullerenation of polycarbonate (PC), a commercially important optical polymer, was achieved by direct reaction of C60 and PC in the presence of azo-bis-isobutyronitrile (AIBN), using 1,1,2,2-tetrachloroethane as the solvent under microwave irradiation (MI). Compared with conventional heating process, MI could significantly enhance the rate of the fullerenation under identical reaction conditions. The C60 content of the fullerene-functionalized polycarbonate (C60-PC) could be controlled via varying the C60/PC feed ratio and the reaction time. The C60-PCs are soluble in common organic solvents such as THF and chloroform. The products were characterized by gel permeation chromatography, UV–vis, FTIR, TGA, DSC, 1H NMR, and 13C NMR. The reaction of C60 with PC under MI was monitored by electron spin resonance spectra, the fullerene radicals were detected in reaction solutions and also in the solid product polymers, indicating the radical mechanism of the reaction. The nonlinear optical property of C60-PCs in THF was investigated by the open-aperture z-scan technique at 527 nm, and its nonlinear absorption coefficient was found to be in the same order as that of C60. POLYM. ENG. SCI., 46:399–405, 2006. © 2006 Society of Plastics Engineers

OVCA1, a tumor suppressor gene, is deleted or lower expressed in about 80% of ovarian cancer. Over expression of OVCA1 in human ovarian cancer A2780 cells inhibits cell proliferation and arrests cells in G1 stage. However, the fact that the molecular mechanism of OVCA1 inhibits cell growth is presently elusive. Here we investigated the potential signaling pathway induced by over-expression of OVCA1. Our results show that over-expression of human OVCA1 in ovarian cancer cells A2780 leads to down-regulation of cyclin D1, and up-regulation of p16, but no effect on the expression of NF-κB. It indicates that OVCA1 could inhibit the proliferation of ovarian cancer cell A2780 by p16/cyclin D1 pathway, but not by NF-κB.

A novel class of HIFU and redox dual responsive polymer with a disulfide bond weak linkage is developed. The novel modality of HIFU and redox triggered release allows for the fine-tuning of the release kinetics of the encapsulants from the micelles in a remote and controlled way.

By using the femtosecond laser spectroscopic techniques, we have studied the ultrafast response and the nonlinear optical properties of three molecules with donor−acceptor structure (denoted as T01, T02, and T03). Two-photon absorption (2PA) cross sections measured by the open aperture Z-scan technique were determined to be 77, 90, and 410 GM for T01, T02, and T03, respectively. The relaxation dynamics of the excited states were measured by two-color femtosecond pump−probe and time-resolved photoluminescence (PL) experiments. By changing the solvent from chloroform (CHCl3) to dimethyl sulfoxide (DMSO), the transient dynamics was found changed significantly and the decay time of PL emission decreased dramatically because DMSO with large dipole moment accelerates the cross-transfer process and the nonradiative process in the molecules.

Two different site-specific cleavage mechanisms for copolymer micelles under ultrasound and redox were confirmed. The finding that ultrasound induced mechanochemical cleavage of central ester bonds can open up a new way in the design of novel ultrasound responsive copolymer micelles for drug release.