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Preparing porous geopolymer for an insulation material was performed by a protein-assisted foaming and non-sintering method. Samples was produced by fly ash, sodium water glass, water and foam as original material, and the protein is used as foaming agent. The influences caused by the dosage (ratio of foam, water glass and water), and curing temperature on the properties were investigated to achieve the optimal performance. Porosity, bulk density, thermal conductivity, mechanical property and thermal evolution behaviors of the produced samples in this study were analyzed accordingly. It was known based on the experimental results that the optimal performance is achieved with a ratio of 35:35:5 for foam, sodium water glass and water under curing temperature of 55 °C, showing a porosity of 90.87%, bulk density of 235.5 kg/m 3 , thermal conductivity of 0.0564 W m −1 K −1 and compressive strength of 0.51 MPa. The obtained research outcomes from this study not only solve the problem of reutilizing waste materials, but also address a new strategy for obtaining non-flammability insulating materials. [ABSTRACT FROM AUTHOR]

Quantitative assessment of ecosystem services in the Grazing Withdrawal Program (GWP) of China is required to understand the effectiveness of environmental protection programs and the sustainability of grassland ecosystems. This study focused on quantitative assessment of changes of key ecosystem services and their driving factors in the GWP from 2000 to 2013. Based on widely used biophysical models, including the GLOPEM-CEVSA model, the precipitation storage method, Integrated Valuation of Ecosystem Services and Trade-Offs (InVEST), Revised Wind Erosion Equation (RWEQ) and Underground Productivity Model (UPM), this study integrated multi-source data to analyze dynamic changes of regulating services, including carbon sequestration, water regulation, sand fixation and soil retention, and the provisioning service of grassland yield. For the GWP area during 2000–2013, the ecosystem pattern remained relatively stable and multiple ecosystem services showed overall improvement but there were local deteriorations. For the 14 years net primary productivity (NPP) and grassland yield (GY) increased substantially. Water regulation in forest, grassland and wetland/water body ecosystems improved slightly. The soil conservation function of the entire ecosystem was slightly enhanced with soil retention showing an increasing spatial homogenization and wind erosion having a decreasing tendency. Ecological restoration and reconstruction efforts and climate change helped to improve ecosystem services. Increases in both temperature and precipitation and ecological rehabilitation had a positive effect on vegetation restoration related to a marked increase of vegetation coverage. Increase in annual precipitation increased rainfall related erosion but also assisted water regulation. Reduction in wind speed effectively lowered the occurrence of wind erosion. Vegetation restoration directly increased NPP and GY, and was conducive to water regulation and soil conservation. However, grassland degradation still continued in local areas. Ecological programs applied to the grasslands of China should be continued. Adopting adaptive management approaches that facilitate the synergy of multiple ecosystem services are required to maximize their benefit to the people of China. [ABSTRACT FROM AUTHOR]

An efficient quenching electrochemiluminescence (ECL) immunosensor based on ECL resonance energy transfer (ECL-RET) was studied for sensitive analysis of prostate specific antigen (PSA). In this protocol, nitrogen-doped graphene quantum dots (NGQDs) which could produce excellent ECL emission, were loaded onto Ni(OH) 2 with the three-dimensional (3D) hierarchical and stacked lamellar structure. Taking advantages of high conductivity and large specific surface area of Ni(OH) 2 , the better electrochemical and ECL behavior of Ni(OH) 2 /NGQDs were presented. As another part of immunosensor, the Fe 3 O 4 @MnO 2 composites with wider ultraviolet absorption range were successfully assembled. The absorption spectra of Fe 3 O 4 @MnO 2 precisely overlapped with the ECL spectra of NGQDs, leading to the significant decrement of ECL signal. Herein, the sandwich-type immunosensor was developed based on the quenching mechanism between NGQDs (ECL donor) and Fe 3 O 4 @MnO 2 (ECL acceptor). The system was optimized to realize reliable determination of PSA concentration within the linear range of 10 −5 –10 ng/mL and a detection limit of 5 fg/mL (S/N = 3). Eminently, the developed method was successfully applied in real serum samples with good recoveries in a range from 94.0% to 102%, indicating the good accuracy of the proposed method for PSA detection. [ABSTRACT FROM AUTHOR]

The post-buckling equilibrium paths (including the whole unstable region) and natural characteristics of fiber-reinforced composite laminated plates with different imperfections under thermal load are studied. Based on the Incremental Von Karman nonlinear relationship, Third-order shear deformation plate theory and Hamilton's principle, the theoretical governing equations are formulated. Firstly, the Cylindrical Arc-length method is developed with a direction judgement to capture the unstable post-buckling path including a number of snap-back and limit points. Then the natural characteristics are derived at the stable buckling position. The results show that in post-buckling state, the number of limit points along the unstable paths is directly related to the number of negative eigenvalues at the initial position. As long as the perturbation load is small enough, the buckling deformation of the flat plate keeps the same under different perturbation load. For the plate with imperfection, if the imperfection is really small, the buckling deformation is the same as that of the flat plate. If the imperfection is relatively larger, the buckling deformation is of high correlation with the imperfection shape. The effects of thermal stress and buckling deformation on the natural frequencies and mode shapes are further analyzed. Some new interesting phenomena are presented. [ABSTRACT FROM AUTHOR]

Cisplatin (CDDP) has received worldwide approval for clinical use in the past decades. However, its development in cancer chemotherapy was overshadowed by severe side effects and drug resistance. Herein, we developed a CDDP drug delivery system with high encapsulation efficiency and near-infrared light stimuli-responsive drug release properties based on the coordination of novel tellurium-containing block polymer (PEG-PUTe-PEG) and CDDP. The nanocarriers made from PEG-PUTe-PEG were loaded with CDDP and indocyanine green (ICG) simultaneously. The coordination chemistry between CDDP and tellurium guaranteed the nanocarrier a high stability in plasma and prolonged circulation time in vivo by reducing possible penetration of water molecule into the nanoparticles. Under the stimuli of a near-infrared laser, an amount of ROS can be generated by irradiation of ICG. The tellurium is easily oxidized by ROS because of the low electronegativity of tellurium. The CDDP could be rapidly released from the nanocarriers along with the oxidation of the tellurium at the tumor sites as the oxidized tellurium will weaken the coordination interaction with CDDP. In addition, the encapsulated ICG played a synergistic antitumor effect through photothermal effect with mild laser irradiation. The integrated strategy achieved higher antitumor efficacy and showed minimal side effects compared with the CDDP alone. [ABSTRACT FROM AUTHOR]

Human beings are inevitably exposed to ubiquitous phthalate esters (PEs) surroundings. The purposes of this study were to investigate the effects of long-term low-dose exposure to the mixture of six priority controlled phthalate esters (MIXPs): dimethyl phthalate (DMP), diethyl phthalate (DEP), di( n -butyl) phthalate (DBP), butyl benzyl phthalate (BBP), di(2-ethyhexyl) phthalate (DEHP) and di- n -octyl phthalate (DNOP), on male rat reproductive system and further to explore the underlying mechanisms of the reproductive toxicity. The male rats were orally exposed to either sodium carboxymethyl cellulose as controls or MIXPs at three different low-doses by gavage for 15 weeks. Testosterone and luteinizing hormone (LH) in serum were analyzed, and pathological examinations were performed for toxicity evaluation. Steroidogenic proteins (StAR, P450scc, CYP17A1 and 17β-HSD), cell cycle and apoptosis-related proteins (p53, Chk1, Cdc2, CDK6, Bcl-2 and Bax) were measured for mechanisms exploration. MIXPs with long-term low-dose exposure could cause male reproductive toxicity to the rats, including the decrease of both serum and testicular testosterone, and the constructional damage of testis. These effects were related to down-regulated steroidogenic proteins, arresting cell cycle progression and promoting apoptosis in rat testicular cells. The results indicate that MIXPs with long-term low-dose exposure may pose male reproductive toxicity in human. [ABSTRACT FROM AUTHOR]

The effect of H 2 O 2 desorption on the direct synthesis of H 2 O 2 from H 2 and O 2 over Pd-TiO 2 (B)/anatase and Pd-anatase has been investigated. The interaction between H 2 O 2 and the support has been studied by isothermal microcalorimetry and molecular dynamics (MD) simulation. H 2 O 2 desorption from TiO 2 (B)/anatase is more facile due to the existence of TiO 2 (B). The accelerated H 2 O 2 desorption from the catalyst surface can effectively decrease the hydrogenation rate of H 2 O 2 over Pd-TiO 2 (B)/anatase, which results in a 57% increase in the selectivity of H 2 O 2 synthesis. [ABSTRACT FROM AUTHOR]

The government service platform, exemplified by the government hotline, has to handle extensive volumes of business documents that contain rich and timely public opinion information and citizens' demands. However, manual processing struggles to process large-scale text data, adversely impacting operating costs and the quality of government services. This study proposes a comprehensive system for business document classification of the government hotline (BDCGHS) in China to address these challenges. BDCGHS leverages information entropy fused with term frequency-inverse document frequency (TF-IDF) weight to mine new words from business documents of the government hotline, and store them in a new word repository. These new words optimize Chinese word segmentation and text representation for text classification. We introduce a novel data structure called nested balanced binary tree to expedite new word mining, yielding a computational speed of almost five times than the Trie trees. Comparative experiments on the THUNews and government hotline datasets validate our proposed improvement BDCGHS algorithm's superior performance 3 % over text classification algorithms. Compared to the latest bidirectional encoder representations from the transformers (BERT) model, BDCGHS enhances the accuracy of order dispatch based on business documents by almost 3 %. It has also demonstrated stable operations in two Chinese cities for over a year, yielding favorable results. [Display omitted] • An embedded balanced binary tree structure is proposed for new word discovery. • A new word database is constructed for the government hotline. • The effects of mainstream classification algorithms are compared based on a new word database. • An intelligent text classification system for the government hotline is constructed and the results have promising results. [ABSTRACT FROM AUTHOR]

Gas chromatography-mass spectrometry (GC-MS) was used to analyze the soluble portions (SPs) of eight lignites which were obtained by extracting using cyclohexane, methanol and ethanol, respectively, as the solvent. For thermal dissolution at 300 °C using cyclohexane, the intermolecular interactions between mobile phase and macromolecules in coal were weakened. Consequently, non- and low-polar compounds such as alkanes and aromatics were well dissolved. Methanol and ethanol were more likely to closely interact with oxygen-containing functional groups and promoted the breakage of hydrogen bonds and weak covalent bonds. Hierarchical cluster analysis classified all the 24 SPs, and the SPs from cyclohexane and ethanol solvents exhibited more similarity. Partial least squares discriminant analysis was established to reproduce the classification results of SPs entirely and accurately. The SPs were further classified by combining a small number of geochemical characteristic compounds rather than massive GC-MS data. • Three low-rank coals retain the biological properties of numerous aquatic plants. • Data mining provides convenient and accurate classification for coal samples. • PLS-DA classification is determined by differential geochemical characteristic compounds. [ABSTRACT FROM AUTHOR]

Polycyclic aromatic compound (PAC) contamination in soil as a result of oil spills is a serious issue because of the huge global demand for fossil energy. This study assessed the vertical variation in polycyclic aromatic hydrocarbons (PAHs), derivatives of PAHs (dPAHs) and bacterial community structure in deep soil with long-term contamination by oil spillage. Our results suggest that the content of total PACs ranged from 1196.6 μg/kg to 14980.9 μg/kg and decreased with depth at all sites. PAHs were the most abundant PACs, with a mean concentration of 6640.7 μg/kg, followed by oxygenated PAHs (mean 156.3 μg/kg) and nitrated PAHs (mean 33.4 μg/kg). PAHs are mainly low molecular weight PACs such as naphthalene, fluorene and phenanthrene, while derivatives of PAHs are all low molecular weight PACs and mainly oxygenated PAHs. Low molecular weight PAHs were an important source of dPAHs under specific conditions. The bacterial community structure showed higher bacterial diversity and lower bacterial richness in shallow soil (2–6 m in depth) than in deep soil (8–10 m in depth). Spearman's analysis confirmed that dramatic bacterial community shifts are a response to contamination. At the genus level, the presence of PACs highly selected for Pseudomonas , belonging to Proteobacteria. Moreover, functional predictions based on Tax4Fun revealed that soil with long-term contamination had a strong potential for PAC degradation. In addition, statistical analysis showed that oxidation-reduction potential (Eh) was closely related to variations of bacterial community composition and function. Finally, Ramlibacter , Pseudomonas , Pseudonocardia , c_MB-A2-108 , f_Amb-16S-1323 , and Qipengyuania were identified by cooccurrence network analysis as keystone taxa contributing to the maintenance of bacterial ecological function. Together, our results provide evidence of tight bacterial effects of PAHs and dPAHs and a more complete understanding of the fate of PACs in deep contaminated soils. [Display omitted] • Total PAC concentrations decreased with increasing soil depth. • Low molecular weight PAHs were an important source of dPAHs. • Variations of Eh and PACs droved assembly of microbial communities. • Actinobacteria was more adaptable to higher PAC pollution than Proteobacteria. • The soil with long-term contamination had a strong potential for PACs biodegradation. [ABSTRACT FROM AUTHOR]

Adiabatic foam has been successfully prepared through sintering sodium silicate which is modified by boric acid. The effect of the sintering temperature, boric acid content and modulus of sodium silicate on the thermal conductivity, density, compression strength and microstructure of the adiabatic foam was studied in detail. In the sintering process, B 3+ ion can take the place of the Si 4+ ion by incorporating into the Si–O–Si structure via Si–O–B bridges, increasing the chemical stability of the adiabatic foam. High temperature, low boric acid content and low modulus of sodium silicate can reduce the thermal conductivity, density and compression strength. In order to meet the application of exterior wall thermal insulation, 450–500 °C of the sintering temperature, 18–24 g boric acid per 600 g sodium silicate solution, and 2.5–2.8 modulus of sodium silicate are chosen. The samples with thermal conductivity less than 0.044 W/m·K, density less than 100 kg/m 3 and compression strength more than 0.7 MPa are obtained. [ABSTRACT FROM AUTHOR]

An ultrasensitive sandwich-type electrochemical immunosensor was designed for the quantitative detection of alpha fetoprotein (AFP). The β-cyclodextrins functionalized graphene sheets (CD-GS) were used as the sensing matrix for immobilizing adamantine-1-carboxylic acid functionalized primary anti-AFP (ADA–Ab 1 ) and enhanced the electron transfer. PdNi alloy nanoparticles decorated N-doped graphene nanoribbons (PdNi/N-GNRs) were used as labels of secondary anti-AFP (Ab 2 ), and PdNi alloy nanoparticles (PdNi NPs) exhibited high catalytic performance towards the reduction of H 2 O 2 . Meanwhile, with good dispersion, large specific surface area and good catalytic performance, N-doped graphene nanoribbons (N-GNRs) significantly amplified the electrochemical signal. Under the optimal conditions, the electrochemical immunosensor exhibited a wide linear range of 0.0001–16 ng/mL with a low detection limit of 0.03 pg/mL. Additionally, the proposed immunosensor showed high specificity, good reproducibility and long-term stability, which have promising application in bioassay analysis. [ABSTRACT FROM AUTHOR]

An underactuated planar acrobot (UPA) is a two-link manipulator with a passive first joint. The control objective for a UPA in a horizontal plane is to move it from an initial position and stabilize it at a target position. Since a UPA is not small-time locally controllable, motion control is a big challenge. This paper presents a new control strategy based on constraints on the motion state. First, constraints on the angles and angular velocities of the two links are devised by integrating the dynamic equation of the UPA. Next, the state constraints are analyzed to discover the motion characteristics. Then, the optimal target position is obtained by solving a motion optimization problem that incorporates those characteristics. Finally, a control strategy based on the Lyapunov function method is devised to achieve the control objective. A numerical example demonstrates the validity of the control strategy. [ABSTRACT FROM AUTHOR]

The bond behavior (failure modes, bond strength, bond stress-slip curves) between steel bar and recycled aggregate concrete after different cycles of freeze – thaw was studied using pullout tests. One recycled aggregate concrete, two types of steel bars: plain steel bars with diameter 12 mm, deformed steel bars with diameter 14 mm, 18 mm, 22 mm and 0, 15, 25, 50, 75 cycles of freeze–thaw were considered in the experiment. Based on the experimental results, the influence of number of freeze–thaw cycles, type of steel bar, and diameter of deformed steel bar on the bond behavior between steel bar and recycled aggregate concrete was studied and analyzed. It was found that the bond strength decreases as the freeze–thaw cycles increased, the drop of bond strength between plain steel bar and recycled aggregate concrete is larger than that between deformed steel bar and recycled aggregate concrete as the freeze–thaw cycles increased, the pullout force and bond strength for deformed steel bar are larger than that for plain steel bar after the same cycles of freeze–thaw. [ABSTRACT FROM AUTHOR]

A novel and sensitive electrochemical immunosensor for ultrasensitive detection of pancreatic cancer biomarker carbohydrate antigen 199 (CA199) was proposed by using Au@Cu x OS yolk–shell nanostructures with porous shells as labels for signal amplification. Au@Cu x OS yolk–shell nanostructures exhibit high electrocatalytic activity toward the reduction of hydrogen peroxide (H 2 O 2 ) as analytical signal. Moreover, secondary antibody (Ab 2 ) can adsorb on the surface of Au@Cu x OS with porous shells which has large surface area and could greatly increase the probability of Ab 2 –antigen interactions thereby leading to higher sensitivity. Reduced graphene oxide–tetraethylene pentamine (rGO–TEPA), containing abundant amine groups, was supported Au nanoparticles as a support platform to immobilize the primary antibody (Ab 1 ). The resulting sensing interface of rGO–TEPA/AuNPs could provide a large electroconductive surface area, allowing high loadings of the biological recognition elements as well as the occurrence of electrocatalytic and electron-transfer processes. Under optimal conditions, the immunosensor exhibited a wide linear response to CA199 ranging from 0.001 to 12 U/mL with a low detection limit of 0.0005 U/mL. The designed immunosensor displayed good precision, high sensitivity, acceptable stability and reproducibility, and has been applied to the analysis of serum with satisfactory results. The proposed method provides a new promising platform of clinical immunoassay for other biomolecules. [ABSTRACT FROM AUTHOR]

• Construct the T-GADF rule to incorporate fault knowledge into images. • Design multi-scale neural network to guide high-precision fault diagnosis. • The Grad-CAM is introduced to visualize the feature learning mechanisms. • The generalization and robustness are verified through various experiments. Intelligent fault diagnosis employing CNN-based techniques has demonstrated promising results in rotating machinery maintenance and management. However, most approaches that rely on time-series vibration signals fail to incorporate the physical knowledge of faults into feature learning, and are subject to obtaining the correlation between input and output characteristics. Furthermore, it is challenging for the neural network to improve feature extraction due to the rigid convolution kernel and the limited receptive field. To address these issues, an intelligent fault diagnosis framework is developed based on vibration image encoding and multi-scale neural networks. Firstly, a novel image encoding rule is designed to convert time-series signals into vibration images, which incorporate the impact characteristics of faults into the model inputs to enhance fault information. Secondly, a multi-scale feature fusion network with dilatated and irregular sampling convolution block is constructed for feature extraction and classification. In addition, a new regularization term is designed to avoid training overfitting. Finally, Grad-CAM is introduced to visualize the region of interest of the model. The proposed method is verified on the datasets with different fault types from our laboratory and DIRG bearing dataset with different fault severities from Politecnico di Torino. The experimental results demonstrate that our diagnostic framework exhibits good generalization and noise robustness, and can achieve high-precision fault diagnosis. [ABSTRACT FROM AUTHOR]

Soil-slurry bioreactor based bioremediation of polycyclic aromatic hydrocarbons (PAHs) contaminated soil was studied through laboratory and pilot-scale trials, in which the degradation mechanism was explored. Indigenous PAH-degrading consortium was firstly screened out and it degraded 80.5% of total PAHs in lab-scale bioreactors. Then a pilot-scale trial lasting 410 days was conducted in two bioreactors of 1.5 m3 to examine the operating parameters and validate the optimum running conditions. During the initial 200 days, the crucial running parameters affecting PAH removal were evaluated and selected. Subsequently, an average PAH removal rate of 93.4% was achieved during 15 consecutive batches (210 days) under the optimum running conditions. The kinetic analysis showed that the reactor under optimum conditions achieved the highest PAH degradation rate of 0.1795 day−1 and the shortest half-life of 3.86 days. Notably, efficient mass transfer of PAHs and high biodegradation capability by bioaugmented consortia in soil-slurry bioreactors were two key mechanisms for appreciable PAH removal performance. Under the optimal operating conditions, the degradation rate of low-molecular-weight (LMW) PAHs was significantly higher than high-molecular-weight (HMW) PAHs; when the mass transfer was limited, there was no significant difference between their degradation behaviors. Both microbial co-metabolism and collaborative metabolism might occur when all PAHs demonstrated low degradation rates. The findings provide insightful guidance on the future assessment and remediation practices of PAH-contaminated sites. [Display omitted] • Indigenous bacterial consortium was more conducive to efficient degradation. • Kinetic analysis of the pilot-scale trial showed rapid and efficient remediation. • Aeration and water-soil ratio were main PAH degradation factors. • Mass transfer determined the PAH degradation behaviors. [ABSTRACT FROM AUTHOR]

[Display omitted] • Monoatomic copper induces platinum atoms to be loaded on N-doped porous carbon. • The Pt mass activity of C-ZIF-CuPt is 4.4 times (ORR) and 6.7 times (HER) of the commercial Pt/C. • The carbon carrier and CuPt clusters have a strong orbital interaction. • Cu doping reduces the ORR overpotential of Pt and the activation energy barrier to water molecules. The preparation of oxygen reduction reaction (ORR) and hydrogen evolution reaction (HER) catalysts with high activity, stability and low platinum loading has always been the focus of research. The single-atom platinum supported catalyst greatly improves the utilization of platinum, but the catalytic activity and selectivity are greatly affected by the platinum coordination environment, and the preparation of the material is difficult. Doping base metals to adjust the electronic structure of platinum is an effective strategy to improve catalyst performance. In this work, copper-platinum alloy nanoparticles were loaded on N-doped porous carbon via a targeted route guided by highly dispersed Cu atoms derived from MOF. The product C-ZIF-CuPt has high activity and high stability ORR, HER bifunctional catalytic performance, which is better than commercial Pt/C (20 wt%). The Pt activity in C-ZIF-CuPt is 4.4 times (ORR) and 6.7 times (HER) than Pt/C. Spectromicroscopic determinations unveiled that strong interactions between carbon carrier and the CuPt alloys contribute to the overall stabilities. DFT calculations show that Cu doping can increase the d-band center of Pt, reduce the ORR overpotential, and the activation energy barrier to water molecules, which is beneficial to ORR and HER catalysis. Under the same carrier conditions, the performance of sub-nano (single atoms, clusters) platinum-supported catalysts (C-ZIF-Cu-Pt) is inferior to C-ZIF-CuPt. This further shows that platinum alloying can effectively improve the performance of the catalyst. [ABSTRACT FROM AUTHOR]

Humulus scanden, rich in flavonoids, is a traditional Chinese medicine. It is widely used in China to treat tuberculosis, dysentery and chronic colitis. In this study, Humulus scandens (H.S) was extracted in different solvents (water, n-butanol, acetic ether and chloroform) and the antioxidant, anti-inflammatory activities of extracts were investigated by four assays including DPPH, reducing power, xylene-induced mouse ear edema and cotton pellet-induced granuloma methods. And then, the acute oral toxicity of extracts and biochemical parameters such as superoxide dismutase (SOD) and catalase (CAT) in blood serum and edematous tissue of rats were also evaluated. Moreover, the active compounds were identified by LC-ESI-QTOF-MS-MS. Results showed that ethyl acetate and n-butanol extracts had the stronger antioxidant activities, while water extract appeared to be weakest among them. The anti-inflammatory test showed that the extract of n-butanol and chloroform had significant anti-inflammatory effects and could improve the activity of SOD and CAT in mice. In general, the site of n-butanol has a stronger antioxidant and anti-inflammatory activity, and 15 compounds were analyzed by LC/Q-TOF-MS/MS technology. The present study confirms the ethnobotanical use of H.S extracts as natural antioxidant, anti-inflammatory, and the composition of the active compound was preliminarily identified. [ABSTRACT FROM AUTHOR]

Abstract: The cartilaginous fish (chimeras, sharks, skates and rays) are the oldest group relative to mammals in which an adaptive immune system founded upon immunoglobulins has been found. In this manuscript we characterize the immunoglobulins of the spiny dogfish (Squalus acanthias) at both the molecular and expressed protein levels. Despite the presence of hundreds of IgM clusters in this species the serum levels of this isotype are comparatively low. However, analysis of cDNA sequences and serum protein suggests microheterogeneity in the IgM heavy chains and supports the proposal that different clusters are preferentially used in the two forms (monomer or pentamer) of this isotype. We also found that the IgNAR isotype in this species exists in a previously unknown multimeric format in serum. Finally, we identified a new form of the IgW isotype (the shark IgD orthologue), in which the leader is spliced directly to the first constant domain, resulting in a molecule lacking an antigen-binding domain. [Copyright &y& Elsevier]

Abstract: A novel electrogenerated chemiluminescence (ECL) biosensor based on the construction of triplex DNA for the detection of adenosine was designed. The ECL biosensor employs an aptamer as a molecular recognition element, and quenches ECL of tris(2,2′-bipyridine) ruthenium (Ru(bpy)3 2+) by ferrocenemonocarboxylic acid (FcA). Through self-assembly technology, the ECL probe of thiolated hairpin adenosine aptamer tagged was self-assembled onto the surface of a gold electrode with an ECL signal producer Ru(bpy)3 2+ derivative (Ru-DNA-1). The adenosine aptamer, including a section of triplex characteristic chain, formatted triplex DNA with two other DNAs (DNA-2, Fc-DNA-3) in the presence of triplex DNA binder coralyne chloride (CORA). Fc-DNA-3 was tagged with an ECL quencher ferrocenemonocarboxylic acid (FcA), a quenching probe. In the presence of adenosine, the aptamer sequence (Ru-DNA-1) prefers to form the aptamer–adenosine complex with hairpin configuration and the switch of the DNA-1 occurs in conjunction with the generation of a strong ECL signal owing to the dissociation of a quenching probe. Meanwhile, a control experiment was performed; the ECL-duplex biosensor was designed to detect adenosine. The detection limits were 2.7×10−10 molL−1 and 2.3×10−9 molL−1 for the ECL-triplex DNA biosensor and ECL-duplex DNA biosensor, respectively, which demonstrated that the ECL-triplex DNA biosensor improved the sensitivity and specificity greatly. [ABSTRACT FROM AUTHOR]

Abstract: An approach of selecting alloying elements to control the size of in situ formed reinforcement in metal melts is proposed. This approach is based on the effect of alloying addition on nucleation of reinforcement predicted by the extended Miedema model and Wilson equation and on growth of reinforcement predicted by diffusion coefficient model. Using this approach, the effect of alloying element addition on the size of in situ formed Mg2Si in (AlN+Mg2Si)/Mg composites is evaluated. The results show that the addition of Ti, V, Mo, Cr, Fe and Mn can delay the nucleation and promote the growth of Mg2Si, while the addition of Ge, Sn, Cu and Zn can promote the nucleation and hinder the growth of Mg2Si. The microstructure of (AlN+Mg2Si)/Mg with the addition of Ti has been investigated based on the theoretical prediction. [Copyright &y& Elsevier]

Abstract: A novel and sensitive sandwich electrochemical biosensor based on the amplification of magnetic microbeads and Au nanoparticles (NPs) modified with bio bar code and PbS nanoparticles was constructed in the present work. In this method, the magnetic microspheres were coated with 4 layers polyelectrolytes in order to increase carboxyl groups on the surface of the magnetic microbeads, which enhanced the amount of the capture DNA. The amino-functionalized capture DNA on the surface of magnetic microbeads hybridized with one end of target DNA, the other end of which was hybridized with signal DNA probe labelled with Au NPs on the terminus. The Au NPs were modified with bio bar code and the PbS NPs were used as a marker for identifying the target oligoncleotide. The modification of magnetic microbeads could immobilize more amino-group terminal capture DNA, and the bio bar code could increase the amount of Au NPs that combined with the target DNA. The detection of lead ions performed by anodic stripping voltammetry (ASV) technology further improved the sensitivity of the biosensor. As a result, the present DNA biosensor showed good selectivity and sensitivity by the combined amplification. Under the optimum conditions, the linear relationship with the concentration of the target DNA was ranging from 2.0×10−14 M to 1.0×10−12 M and a detection limit as low as 5.0×10−15 M was obtained. [Copyright &y& Elsevier]

Abstract: The thermodynamic work of solid–liquid adhesion in multicomponent melts is important in many fields. Quantitative calculation of the work of solid–liquid adhesion has not, however, been well developed. A model for quantitative calculation of the work of solid–liquid adhesion in a multicomponent melt has been proposed based on the expansion of the Maclaurin infinite series in the neighborhood of each pure component of the binary alloy. The parameters used in this model are assessed through the statistical thermodynamic model of surface and interface tensions, which is based on the monolayer approximation for metal–vapor and metal–solid interfaces and Bragg–Williams statistics. According to the present model, the work of adhesion–concentration dependency over the whole concentration range for binary alloy can be theoretically determined from only the physical parameters of the pure components. The model has been successfully applied to calculate the work of adhesion for various solid–liquid systems. [Copyright &y& Elsevier]

Abstract: Nanoscale Co and Ni catalysts in silica were synthesized using sol–gel method for hydrogen production from steam reforming of methanol (SRM) in silicon microreactors with 50μm channels. Silica sol–gel support with porous structure gives specific surface area of 452.35m2 g−1 for Ni/SiO2 and 337.72m2 g−1 for Co/SiO2. TEM images show the particles size of Ni and Co catalysts to be <10nm. The EDX results indicate Co and Ni loadings of 5–6wt.% in silica which is lower than the intended loading of 12wt.%. The DTA and XRD data suggest that 450°C is an optimum temperature for catalyst calcination when most of the metal hydroxides are converted to metal oxides without significant particle aggregation to form larger crystallites. SRM reactions show 53% methanol conversion with 74% hydrogen selectivity at 5μLmin−1 and 200°C for Ni/SiO2 catalyst, which is higher than that for Co/SiO2. The activity of the metal catalysts decrease significantly after SRM reactions over 10h, and it is consistent with the magnetization (VSM) results indicating that ∼90% of Co and ∼85% of Ni become non-ferromagnetic after 10h. [Copyright &y& Elsevier]

The incorporation of aluminum (Al) into explosives represents a facility and efficient way to enhance the energy output through the secondary reaction between Al and the detonation products of explosive. The Al/O ratio and microstructure of HMX/Al play critical roles in combustion performance and energy output. Herein, a gradient structured HMX/Al composite has been designed and fabricated via 3D printing technology using well-dispersed HMX/Al-based ink. For HMX/Al lines, the second reaction heat increases from 196.5 J/g to 1644.8 J/g and the burning rate would decrease from 14.6 to 12.0 mm/s with Al content increased from 10 to 30 wt%. For gradient structured HMX/Al, the burning rate could be controlled by varying the component ratio and the burning rate of each component in the gradient structure was higher than that of the normal HMX/Al counterpart. Furthermore, a gradient evolution of pressure output was monitored for gradient structured HMX/Al cylinder ignited by the laser. These results indicate that the gradient structure as an effective approach can tune combustion performance and energy output of HMX/Al. [ABSTRACT FROM AUTHOR]

Niobium oxalate was employed to obtain BiNbO 4 for the first time and the BiNbO 4 nanorods were successfully synthesized through a hydrothermal method at a low temperature. Oxygen vacancies were introduced into the BiNbO 4 nanorods, lowering the BiNbO 4 bandgap. The O-deficient BiNbO 4 exhibited excellent sonocatalytic performance. [ABSTRACT FROM AUTHOR]

In order to relieve high residual stresses between ceramics and metals during brazing processes, an AgCuTi/graphene-reinforced Cu foam composite filler was developed and used to braze the ZrB 2 -SiC ceramic and Inconel 600 alloy. Microstructures and shear strengths of the joints were systematically studied. The joints are composed of TiFe 2 , TiCu, TiC, Cu(s, s), Ag(s, s), and Ti 5 Si 3 phases. It is found the addition of graphene on the Cu foam surface can effectively retard diffusions of metal atoms and avoid the collapse of the foam matrix. After being brazed at 900 °C, the joint can get a maximum shear strength of 157 MPa, much higher than those brazed without graphene addition. The high shear strength was investigated in detail and attributed to the integrity of the Cu foam, formation of the TiC and thickness of the reaction layer at the ceramic side. [ABSTRACT FROM AUTHOR]

The multilayer nanostructured FG/Al (MN-FG/Al) energetic materials with particle mosaic have been rapidly assembled by the intercalation-like method, and the energy output performance of these MN-FG/Al energetic materials can be effectively regulated by changing the ratio of FG and nAl. [Display omitted] • Propose an efficient strategy towards the design of energetic materials. • Multilayer nanostructured have assembled by the intercalation-like method. • Energy output can be effectively regulated by changing the ratio of FG and Al. • Oxygen content determines the reaction and obtains different pressure outputs. Fluorinated reactive materials as new energetic materials are widely studied because of their high combustion heat and the ability to release large amounts of gaseous products. In order to further improve combustion reaction and the energy release efficiency, structural processing strategy is usually adopted to construct unique microstructures for fluorinated reactive materials. In this work, it is found that fluorinated graphene (FG) and nano-aluminum (nAl) can be rapidly assembled by the intercalation-like method to form multilayer nanostructured energetic materials with particle mosaic. Based on this, the energy output performance of these multilayer nanostructured energetic materials can be effectively regulated by changing the ratio of FG to nAl. The shortest laser ignition delay time (8 ms) and the longest burning time (56 ms) can be achieved for the multilayer nanostructured energetic material with proper FG/Al ratio, while the burning rate of the sample spline can reach 14.83 cm/s. In addition, the reaction process of multilayer nanostructured FG/Al energetic materials depends upon oxygen content that participates in the reaction in different atmospheres, leading to the different pressure output performance. This study provides a promising strategy for the further application of fluorinated reactive materials in the field of energetic materials. [ABSTRACT FROM AUTHOR]

[Display omitted] • G-A MN patch is synthesized via UV crosslinking of GelMA and acrylic acid (AA). • G-A MN patch enables rapid analytes extraction for subsequent detection. • G-A MN patch detects breast cancer occurrence earlier than standard methods. • Timely diagnosis extends survival in the breast cancer model. • Provide a promising alternative strategy for breast cancer screening. Early diagnosis and treatment are crucial for breast cancer patients. Interstitial fluid (ISF) shows promise for early disease screening, but its extraction for biomarker detection is challenging. To address this, we designed a microneedle (MN) patch for minimally invasive and rapid ISF extraction through materials engineering, which could improve cancer detection, ease the burden on medical resources, and increase patient compliance. Via UV crosslinking, the water absorbing moiety, acrylic acid (AA), can be polymerized and crosslinked with gelatin methacrylate (GelMA). The resulting GelMA-AA MN (G-A MN) can rapidly extract different analytes. One piece of G-A MN patch can aspirate about 1.29 mg (≈ 1.29 µL) of ISF from mice within 60 s. We further applied G-A MN for breast cancer screening in the 4T1 orthotopic mice breast cancer model and genetically engineered breast cancer model. By measuring the tumor markers carcinoembryonic antigen (CEA) and glycoantigen CA15-3, G-A MN could detect the cancer occurrence earlier than other standard screening methods, including blood tests, ultrasound, or Micro-CT. Furthermore, earlier diagnosis led to timely chemotherapy treatment and resulted in prolonged survival in the mice 4T1 breast cancer model. In conclusion, G-A MN enabled rapid ISF extraction for biomarker analysis in a minimally invasive manner. G-A MN facilitated detection outperformed other common diagnostic methods, representing a promising alternative breast cancer screening strategy. [ABSTRACT FROM AUTHOR]

The ECL emission of simple and stable zirconium dioxide nanomaterials has always been a blank slate in the ECL sensors field. In this work, zirconium dioxide (ZrO 2)-titanium dioxide (TiO 2)-gold nanoparticle (AuNPs) composite (ZT-Au), a novel self-enhanced ECL emitter, was introduced the system of dual-quenching ECL immunosensor. The anodic luminescence of ZrO 2 in the system of tripropylamine (TPrA) as a co-reagent was first reported and explored. Meanwhile, TiO 2 was designed into the ECL scheme as a co-reaction accelerator to form the ZrO 2 /TPrA/TiO 2 ternary system, which can efficiently amplify the ECL signal of the emitter. In addition, cuprous oxide-triaminophenol (Cu 2 O-APF) as the quencher was devoted to the dual-quenching sensing strategy. The dual-quenching mechanism that effectively boosted the immunosensor sensitivity was adequately investigated and conjectured in this paper. The sensing model based on the luminophor ZT-Au and the quencher Cu 2 O-APF was utilized for the detection of D-dimer, a reliable marker for the diagnosis and evaluation of thrombotic diseases. The short peptide ligands NARKFYKGC (NFC) with efficient biological affinity were used to site-directionally capture antibodies for adequately protecting the activity of antigen binding sites during the construction of the immunosensor. The implemented immunosensor was equipped with a broad linear range of 0.01–500 ng/mL and a low detection limit of 3.6 pg/mL. The original methodology opens up the field of vision for the detection of additional biomarkers. [ABSTRACT FROM AUTHOR]

[Display omitted] • Co 3 O 4 @Co(OH) 2 photocatalyst was synthesized by a one-pot hydrothermal method. • Co 3 O 4 @Co(OH) 2 was photocatalytic active in PS MPs degradation and H 2 production. • The photocatalytic degradation was assessed by morphological changes of the MPs. • Photocatalytic H 2 production was of 43 μmol g−1. • Band diagram and mechanism could be proposed for both applications. The 2D semiconductors are important players in environmental and energy fields due to their unique catalytic and physical properties defined by their dimensionality. Versatile functionalities on one 2D matrix will enlarge its application scopes but require dedicated engineering paths. In this work, we present a cross-dimensional strategy by decorating 0D Co 3 O 4 onto 2D Co(OH) 2 to form a multifunctional photocatalyst. The one-pot hydrothermally synthesized Co 3 O 4 @Co(OH) 2 composite is capable of degrading polystyrene microplastics with an efficiency of 40% under 0.495 W white LED illumination. In a separated experiment, H 2 evolution reaction from water splitting was evaluated in absence of sacrificial agents leading to 43 μmol g−1 and to an apparent quantum efficiency of 3.48% at 420 nm. The study of the energy band diagrams by UV–Visible and ambient photoemission spectroscopy and the analysis of the radicals involved in the reaction of photocatalytic degradation allow to unveil the mechanisms for both the processes herein studied. Finally, we could confirm that the heterostructure benefits the redox potentials of 2D and 0D counterparts and facile electron transfers when crossing two different dimensions. These results provide guidelines and inspiration for cross-dimensional activations of low-dimensional materials for versatile functionalities. [ABSTRACT FROM AUTHOR]

• Dispersal probability is more sensitive to distance thresholds compared to effective conductance. • Combining modularity with connectivity for landscape functional change analysis. • ' Flow ' module based on Infomap has similar theoretical hypotheses with circuit theoretic model. • Infomap can identify the hierarchical module structure of habitat network. Recent studies show that modularity is a crucial aspect of habitat network connectivity that affects the likelihood of population persistence despite unpredictable perturbations, therefore, modularity should be considered while restoring connectivity in highly fragmented landscapes. However, what methods or models can be applied to an integrated analysis of connectivity and modularity are rarely discussed. An integrated approach is proposed to model connectivity of habitat networks and identify module structure on the basis of comparing Least Cost Path (LCP) with circuit-theoretic model, Informap with Newman Girvan's modularity score Q method. To measure connectivity between habitat patches, dispersal probability based on LCP and effective conductance based on circuit-theoretic model were calculated respectively and compared under different cost-weighted distance thresholds of 150, 500, 1000, 2500, 5000, 10,000. Then, results of six scenarios were compared using Infomap and Newman-Girvan's modularity score Q to demonstrate the utility of the two methods in identifying modular structure. These procedures were carried out in a simulated landscape. The results show that (1) compared with effective conductance, dispersal probability is more sensitive to the change of cost-weighted distance thresholds.(2) increasing cost-weighted distance thresholds lead to a decrease in current density of pinch points and resistance distance of corridors between two habitats, but it improves habitat connectivity.(3) the results of modules identified by Newman-Girvan's method differ noticeably from that of Infomap, but Infomap can identify the hierarchical module structure of the habitat network. Our approach offers an effective means for characterizing functional structure of habitat networks combining connectivity with modularity. Effective conductance has a wider application in identifying important landscape elements, and Infomap can extract multiple levels of network structure, which likely reflect structures determined by different ecological processes at different scales. [ABSTRACT FROM AUTHOR]

Abstract In this paper, brazing behaviors between ZrB 2 SiC and Ti 6Al 4V by Cu foam interlayer were studied. The microstructure, formation mechanism, mechanical property and fracture surface of the joints were systematically studied. The results showed that the phases in the joints were α + β -Ti, TiCu, Ti 2 Cu, Cu(s, s), TiC, TiB 2 and Ti 3 SiC 2. An optimum shear strength reached up to 435 MPa at a brazing temperature of 910 °C and holding time of 20 min. Such a shear strength was 90 MPa higher than the one without the Cu foam. The obtained high shear strength of joint was discussed from microstructure and residual stress. With the increase of brazing time, Cu(s,s) gradually disappeared and the content of Ti 2 Cu intermetallic compound increased, which was harmful for the joint. Furthermore, the residual stress of joint with Cu foam was calculated to be 324 MPa, lower than the one without Cu foam interlayer. [ABSTRACT FROM AUTHOR]

Abstract Detecting the small amounts of proteins interacting effectively with the solid film electrodes surface still remains a challenge. To address this, in this work, a new approach was proposed by the combination of the adhesion forces and the molecular interaction measured with AFM. Cytochrome c (Cyt C) interacting effectively with TiO 2 nanotube arrays (TNAs) was chosen as a probe. The amounts of Cyt C molecules interacting effectively on TNAs surface (C TNA) range from 5.5 × 10−12 to 7.0 × 10−12 mol/cm2 (68.2–86.8 ng/cm2) and they are comparable with the values obtained by the electrochemistry method in the literature, in evidence of the accuracy of this AFM-based approach. The reliability of the proposed approach was further verified by conducting Surface Enhanced Raman Scattering (SERS) measurements and estimating the enhancement factor (EF). This interaction-based AFM approach can be used to accurately obtain the small amounts of adsorbed substances on the solid film electrodes surface in the applications such as biosensors, biocatalysis, and drug delivery, etc. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

Abstract A sensitive dual mode competitive electrochemical immunosensor for the detection of B-type natriuretic peptide (BNP) was successfully fabricated, which based on differential pulse voltammetry (DPV) and amperometric i-t curve response modes. Polyaniline (PAN) and tin dioxide (SnO 2) were loaded on graphene sheets (GS), which could effectively promote the electron transfer process, thereby amplifying the current signal and increasing the sensitivity of the immunosensor. To promote biocompatibility, gold nanoparticles (Au) were incorporated on GS/SnO 2 /PAN (GS/SnO 2 /PAN-Au). GS/SnO 2 /PAN-Au complex was gotten to act as the platform which could provide a clearly DPV signals. N-doped carbon nanotubes (N-CNTs) embellished by ZnCo 2 O 4 quantum dots (ZnCo 2 O 4 /N-CNTs) with excellent catalytic properties for the reduction of H 2 O 2 was gotten to act as the label of the antibody-BNP (Ab), providing an obviously current signal through amperometric i-t curve method. A large quantity of BNP could be stable loaded in the modified electrode via GS/SnO 2 /PAN-Au with excellent electrical conductivity and good biocompatibility, which could compete with target-BNP to combine Ab that labelled by ZnCo 2 O 4 /N-CNTs. Under the optimum conditions, the immunosensor exhibited remarkable analytical performance of a linear range from 0.01 pg/mL to 1 ng/mL with a detection limit of 3.4 fg/mL for quantitative detection of BNP (S/N = 3). This method was able to become a universal strategy for other biological detection. Highlights • A dual mode competitive electrochemical immunosensor was fabricated. • GS/SnO 2 /PAN-Au possessed excellent electrical conductivity and good bioactivity. • ZnCo 2 O 4 /N-CNTs owned excellent catalytic properties for reduction of H 2 O 2. • The electrochemical immunosensor employed DPV and amperometric i-t curve methods. • The designed immunosensor exhibited low detection limit of 3.34 fg mL−1 for BNP. [ABSTRACT FROM AUTHOR]

Abstract A high sensitivity photoelectrochemical (PEC) immunosensor for amyloid beta (Aβ) detection, which has great neurotoxic effect on the progression of Alzheimer's disease (AD), was presented based on the sensitization of Mn2+ doped CdSe (Mn:CdSe) to Bi 2 WO 6 /CdS electrode. Bi 2 WO 6 was synthesized successfully with a unique flower-like amorphous structure, providing a merit to load functional CdS for obtaining an expected PEC response. Mn:CdSe was used to label Aβ for acquiring Mn:CdSe-Aβ bioconjugate and enhancing the detection sensitivity via the competitive immunoreaction of Mn:CdSe-Aβ and Aβ with antibody immobilized on Bi 2 WO 6 /CdS electrode. The doped of Mn2+ in CdSe nanoparticles could induce energy defect that impeded the recombination of photo-generated charges, and greatly enhanced PEC response for ultrasensitive detection of Aβ. The proposed immunosensor for Aβ showed a linear range of 0.2 pg mL−1–50 ng mL−1 with a detection limit of 0.068 pg mL−1, also with good stability, high selectivity, and acceptable reproducibility. The sensitization of Mn:CdSe provided a new way for preparation of highly sensitive protein biosensors. Highlights • A novel PEC immunosensor for ultrasensitive detection of Aβ was proposed at Bi 2 WO 6 /CdS modified electrode. • Aβ was labeled with Mn2+ doped CdSe for signal amplification. • The sensitization of Mn:CdSe to Bi 2 WO 6 /CdS remarkably enhanced the PEC intensity. • The biosensor for Aβ exhibited the detection limit of 0.068 pg mL−1. [ABSTRACT FROM AUTHOR]

Abstract In this study, the Ag-loaded Sb 2 WO 6 photocatalysts have been successfully synthesized by a facile solvothermal method. The as-prepared Ag-loaded Sb 2 WO 6 microspheres were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), high-resolution transmission electron microscopy (HRTEM), high angle annular dark-field transmission electron microscopy (HAADF-STEM), energy-dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), UV–Vis diffuse reflectance spectroscopy (UV-DRS) and the Brunauer–Emmett–Teller (BET) method. Results indicate that metallic Ag was successfully grown on Sb 2 WO 6. The photocatalytic activities of the Ag-Sb 2 WO 6 photocatalysts were evaluated by degradations of MO, RhB and MB under UV light and visible light. It is found that the photocatalytic activity is excellent and superior after the decoration of the metallic Ag nanoparticles. A possible photocatalytic mechanism was proposed. Graphical abstract Ag-loaded hierarchical microspheres have been synthesized by a facile solvothermal method. The samples exhibited the higher photocatalytic activity under UV irradiation than pure Sb 2 WO 6. Unlabelled Image Highlights • The hierarchical Ag-loaded Sb 2 WO 6 microspheres have been prepared by solvothermal method. • Photocatalytic activity of Ag-loaded Sb 2 WO 6 was enhanced under different light irradiation. • A possible photocatalytic mechanism was proposed. [ABSTRACT FROM AUTHOR]

Highlights • Grassland yield on the Tibetan Plateau for a 26-year long sequence was estimated, and showed a fluctuating increase trend. • The grassland was overloaded in 2013, although the grazing pressure had decreased gradually since 1988. • Warming temperature and the effectiveness of ecological restoration programs jointly promoted the positive increase of grassland yields. Abstract Accurate and periodic assessment of grassland yield (GY) is of great importance for the management of high altitude plateau grasslands. The Tibetan Plateau (TP) is a very important pastoral area that provides a microcosm of typical alpine grassland ecosystems. Based on remote sensing data, meteorological datasets and observational plant biomass data, we used the Global Production Efficiency Model and Soil and Atmosphere Model (GLOPEM-CEVSA) to estimate GY and its response to climate change and anthropogenic activities on the TP from 1988 to 2013. We quantitatively analyzed spatiotemporal dynamic changes of GY for four geomorphological divisions and five main grassland types. For the 26 years of the study, average annual total GY was 515.8 kg/ha/yr and gradually decreased from the southeast to the northwest of the TP. Annual GY fluctuated from year to year but had an overall positive trend (4.2 kg/ha/yr). Spatiotemporal variation of GY was greatly influenced by spatial heterogeneity. For the total area, the proportion showing a significant increase in GY was 45.2%, while only 12.6% showed a significant decrease. For the main grassland types, GY of Alpine Meadow was highest and had the highest slope of increase. The pattern of decrease of GY from the southeast to the northwest was predominantly related to climate gradients. Regional correlation analysis indicated that warming temperature promoted positive increase of GY for almost all the region. Annual precipitation was related to a less significant decreasing trend of GY over all the TP apart from an increase of GY in the middle area of the north. The grazing pressure index decreased over the years by control of livestock numbers, the reduction of grazing pressure assisting restoration of alpine grasslands. However, grazing pressure on the TP in 2013 remained too high and overloaded. Nevertheless, grassland protection and restoration projects have mitigated grassland degradation in some areas, promoted grassland restoration, and increased incomes of herdsmen. The study indicates that continuation of these projects is critical for the restoration and sustainable use of the TP grasslands. [ABSTRACT FROM AUTHOR]

Abstract An ultrasensitive label-free photoelectrochemical (PEC) immunosensor with high visible-light activity was developed for quantitative detection of amyloid β-protein (Aβ) by cross-linking anti-Aβ antibody onto the Ag 2 S sensitized SnO 2 /SnS 2 nanocomposites. Specifically, SnO 2 with flower-like porous nanostructure was innovatively applied in PEC immunosensor as a basal material. It could form a heterostructure with SnS 2 , which brought about the sensitization of SnO 2 and enhanced the separation of photogenerated electrons and holes. Moreover, Ag 2 S was in-situ growth on the surface of SnO 2 /SnS 2 , which further enhanced the photocurrent response significantly. Therefore, SnO 2 /SnS 2 /Ag 2 S could form stepwise band-edge structure, which benefited the light harvesting and provided a good foundation for sensor construction and detection. Under optimal conditions, the PEC immunosensor was used to detect the content of Aβ and exhibited a wide linear concentration range from 0.5 pg mL−1 to 100 ng mL−1, with low limit of detection (0.17 pg mL−1) and limit of quantification (0.56 pg mL−1). Additionally, the designed PEC immunosensor exhibited good reproducibility, specificity, and stability which may find potential applications in the biosensor, biomedicine, clinical diagnosis, photocatalysis and other related fields. Highlights • A label-free PEC immunosensor was developed based on SnO 2 /SnS 2 /Ag 2 S nanocomposites. • SnO 2 /SnS 2 /Ag 2 S nanocomposites exhibited excellent photoelectrochemical performance. • The PEC immunosensor displayed highly sensitive detection toward amyloid β-protein. [ABSTRACT FROM AUTHOR]

Cardiac troponin I (cTnI) is a specific and sensitive biomarker for the early diagnosis of acute myocardial infarction and for the subsequent clinical treatments. In this work, novel electrochemical sensing platform for sensing of cTnI based on aptamer-MoS 2 nanoconjugates was proposed. For comparison, core-shell Au@SiO 2 @Au nanoparticles were also used for sensing of cTnI. The sensing schemes and electrochemical responses of the proposed sensors were investigated by electrochemical impedance spectroscopy (EIS) in 5.0 mM K 3 [Fe(CN) 6 ]/K 4 [Fe(CN) 6 ] (1:1) solution containing 0.1 M KCl, respectively. Results showed that the aptamer-Au@SiO 2 @Au based aptasensor shows a linear rage of 10 pM-10.0 μM with the detection limits of 1.23 pM For the aptamer-MoS 2 nanosheets based aptasensor, the linear range for cTnI detection was from 10 pM to 1.0 μM with a lower detection limit of 0.95 pM Meanwhile, both the sensors were successfully applied for detection of cTnI in human blood samples. The two kinds of aptsensors have been successfully used for detecting of cTnI in human blood serums. Moreover, no negligible signal changes could be observed in the presence of non-targets of CK-MB and Myo, suggesting the good potential for clinic diagnosis. [ABSTRACT FROM AUTHOR]

• Four new lytic phages infecting Cronobacter sakazakii were isolated from sewage samples. • Morphological, physiological, genomic characteristics of phages were characterized. • C. sakazakii phage origin, evolution and their connections were studied by a comparative genomics analysis. Cronobacter sakazakii, a foodborne pathogen, can contaminate powdered infant formula (PIF) and cause life-threatening meningitis, necrotizing colitis and meningoencephalitis in infants. Bacteriophages are increasingly considered an efficient approach to target pathogenic microorganisms. In the current study, four virulent phages that can infect C. sakazakii were isolated from sewage samples, and their biological and complete genomic characteristics were analyzed. A comparative genomic analysis was performed to investigate the functional genes and phylogenetic evolution of the four phages. The results revealed that all four phages belonged to the Ackermannviridae family. Notably, the viral burst size of the phages ranged from 10 to 250 PFU/cell, following a latent period of 5 min to 20 min. Moreover, phages were stable over a pH range of 4 to 10 and a temperature range of 50 ℃ to 60 ℃. The full length of the complete genomes of the four phages ranged from 41,929 bp to 146,806 bp, containing lysis genes but no virulence genes. Phylogenetic tree analysis showed that the four phages were members of two distinct genetic groups with a significant genetic evolutionary distance between each C. sakazakii phage. Furthermore, the antibacterial assay revealed that all phages could inhibit the growth of C. sakazakii for up to 24 h. Taken together, the four phages have huge prospects as additives in dairy products to counter C. sakazakii. [ABSTRACT FROM AUTHOR]

Phenanthrene, as a widespread polycyclic aromatic hydrocarbons (PAHs) contaminant in vitro and in vivo of plant, has the characteristics of carcinogenicity, teratogenicity and mutagenicity. This work aimed to explore the phenanthrene metabolic mechanism by Phomopsis liquidambari in vitro, as well as the bioremediation ability through P. liquidambari -rice combination. This strain was able to use phenanthrene as source of carbon and energy to grow, more than 77% of added 50 mg L −1 phenanthrene was removed after 10 d in MSM. We identified the metabolic products via HPLC-MS and proposed two possible degradation pathways. Phenanthrene was firstly combined with oxygen to become phenanthrene 9,10-oxide, and then degraded to 9-phenanthrol, followed by oxidization to 9,10-dihydroxyphenanthrene. In addition, that epoxide (phenanthrene 9,10-oxide) was also hydrolyzed to phenanthrene trans -9,10-dihydrodiol, and then dehydrogenized to 9,10-dihydroxyphenanthrene, which was further degraded to 9,10-phenanthrenequinone; during this metabolic pathway, the changes of P450 monooxygenase, epoxide hydrolase, dehydrogenase and catechol 2,3-dioxygenase activities and their corresponding gene transcription levels were closely related. What's more, P. liquidambari could combine with rice to eliminate phenanthrene accumulated in vivo of rice seedlings, and the removal rate in inoculation treatment represented a significant difference (increased 25.68%) compared with uninoculation treatment after cultivation 30 d. Therefore, we concluded that P. liquidambari could not only respond to phenanthrene pollution stress in vitro but also exert a mitigation effect on plants accumulated phenanthrene. This work provides a foundation for applying endophytic fungi to PAHs bioremediation in vitro and in vivo. [ABSTRACT FROM AUTHOR]

In this work, Ru(bpy) 3 2+ encapsulated in metal–organic frameworks (MOFs) UiO-67 (Ru(bpy) 3 2+ /UiO-67) as luminophor was easily prepared and firstly applied in constructing an electrochemiluminescence (ECL) immunosensor to efficiently estimate diethylstilbestrol (DES). The competitive method-based ECL immunosensor platform was fabricated by amino-silicon dioxide which possesses large surface area. The poriness of UiO-67 was splendid so that Ru(bpy) 3 2+ could be easily encapsulated. Ru(bpy) 3 2+ /UiO-67 with excellent ECL luminescence signal existed large specific surface area for easily labeled with antibodies. DES competed with bovine serum albumin-diethylstilbestrol (BSA-DES) for binding to antibody-specific sites in the constructed immunosensor. However DES was micromolecule, which was easier to bond to antibodies than BSA-DES. The ECL signal was gradually decreases with the increase of the concentration of DES. Under optimal conditions, the proposed immunosensor exhibited a wide linear range from 0.01 pg mL −1 to 50 ng mL −1 with a low detetion limit of 3.27 fg mL −1 (S/N = 3). The novel fabricated immunosensor with interference immunity and high stability may cause an attractive approach for the other targets determination. [ABSTRACT FROM AUTHOR]

In this study, a sensitive sandwich-type electrochemical immunosensor was fabricated for the detection of alpha fetoprotein (AFP) based on Co 3 O 4 @MnO 2 -thionine (Co 3 O 4 @MnO 2 -Th) and the screen printing technique. Meanwhile, the pseudo enzyme-linked immunosorbent assay (pseudo-ELISA) method was applied in fabricating the immunosensor. Screen-printed carbon electrode (SPCE) was applied for achieving the detection of AFP. Simultaneously, the amino functionalized Co 3 O 4 @MnO 2 -Th was employed as secondary label and could greatly improve the electrochemical response signal, which was beneficial for detecting AFP. Differential pulse voltammetry (DPV) was applied for the detection of AFP and electrochemical impedance spectroscopy (EIS) confirmed the successful fabrication of the immunosensor. Under optimal conditions, the immunosensor exhibited a linear response toward AFP in the range of 0.001–100 ng/mL, with a low detection limit of 0.33 pg/mL. Simultaneously, the proposed immunosensor displayed acceptable selectivity, excellent stability and well reproducibility. Furthermore, this proposed strategy may open up new ideas and find many potential applications in the detection of other tumor markers. [ABSTRACT FROM AUTHOR]

Understanding spatiotemporal variation of PM 1 (mass concentrations of particles with aerodynamic diameter < 1 μm) is important due to its adverse effects on health, which is potentially more severe for its deeper penetrating capability into human bodies compared with larger particles. This study aimed to quantify the spatial and temporal distribution of PM 1 across China as well as its ratio with PM 2.5 (<2.5 μm) and relationships with meteorological parameters in order to deepen our knowledge of the drivers of air pollution in China. Ground-based monitoring PM 1 and PM 2.5 measurements, along with collocated meteorological data, were obtained from 96 stations in China for the period from November 2013 to December 2014. Generalized additive models were employed to examine the relationships between PM 1 and meteorological parameters. We showed that PM 1 concentrations were the lowest in summer and the highest in winter. Across China, the PM 1 /PM 2.5 ratios ranged from 0.75–0.88, reaching higher levels in January and lower in August. For spatial distribution, higher PM 1 /PM 2.5 ratios (>0.9) were observed in North-Eastern China, North China Plain, coastal areas of Eastern China and Sichuan Basin while lower ratios (<0.7) were present in remote areas in North-Western and Northern China (e.g., Xinjiang, Tibet and Inner Mongolia). Higher PM 1 /PM 2.5 ratios were observed on heavily polluted days and lower ratios on clean days. The high PM 1 /PM 2.5 ratios observed in China suggest that smaller particles, PM 1 fraction, are key drivers of air pollution, and that they effectively account for the majority of PM 2.5 concentrations. This emphasised the role of combustion process and secondary particle formation, the sources of PM 1 , and the significance of controlling them. [ABSTRACT FROM AUTHOR]

To obtain ideal implant materials, we hot extruded Mg-2.0Zn-0.5Zr-3.0Gd solid-solution alloys, and studied extrusion temperature impacts on materials properties. Fine dynamic recrystallized (DRXed) grains (∼5 μm) and elongated coarse un-dynamic recrystallized (unDRXed) deformed grains turned out at the range of 470–490 °C, but changed to bigger ones (∼8 μm) and abnormal growth (30–40 μm) at 490–510 °C. Precipitated phases consist of rod-like (Mg, Zn) 3 Gd particles and newly precipitated Mg 2 Zn 11 rectangles. The alloy extruded at 490 °C meets all mechanical and anticorrosive requirements for biomaterials, thanks to evenly distributed second phases via the solid solution, and the grain refinements through the hot extrusion. [ABSTRACT FROM AUTHOR]

In this work, a highly-efficient competitive method-based electrochemiluminescence (ECL) immunosensor was proposed based on {[Ru(bpy) 3 ][Cu 2x Ni 2(1−x) (ox) 3 ]} n (Cu/Ni/Ru) as luminophor to efficiently detect aflatoxins B1 (AFB1). Cu/Ni/Ru exhibited excellent ECL behavior. While polyethyleneimine capped silicon dioxide (PEI@SiO 2 ) could decrease the ECL performance of Cu/Ni/Ru due that PEI could destroy the structure of Cu/Ni/Ru via producing the complex between PEI and metal ions (Cu(II)/Ni(II)), inducing the release of Ru(bpy) 3 2+ . Since Au nanoparticles can directly combine with antibody and antigen, the Cu/Ni/Ru and PEI@SiO 2 was functionalized by Au nanoparticles. The quantitative detection of AFB1 was based on the competitive binding between AFB1-bovine serum albumin labeled Au-PEI@SiO 2 (Au-PEI@SiO 2 -AFB1-BSA) and free AFB1 with antibody-AFB1 which immobilized on Au-Cu/Ni/Ru. The ECL signal increased with augmenting the concentrations of the free AFB1 due to less Au-PEI@SiO 2 -AFB1-BSA combining with antibodies. Under optimal conditions, the proposed immunosensor exhibited a wide linear range from 0.01 ng mL −1 to 100 ng mL −1 with a detection limit of 0.0039 ng mL −1 (S/N = 3). The proposed immunosensor also provides a promising approach for ultrasensitive detection of other mycotoxins. [ABSTRACT FROM AUTHOR]

The effect of a self-assembly nucleating agent, N , N ′, N ″-tricyclohexyl-1,3,5-benzenetricarboxylamide (BTCA), on the crystallization behavior of poly(lactic acid) (PLA) was probed by time-resolved Fourier transform infrared spectroscopy (FTIR) and wide angle X-ray diffraction (WAXD). The vibrational changes associated with inter- and intra-chain interactions during crystallization were monitored. In the initial period of crystallization, the order of intensity changes is as follows: 1458 cm −1 > 1210 cm −1 » 921 cm −1 , 1458 cm −1 ∼ 1210 cm −1 > 921 cm −1 , and 1458 cm −1 ∼ 1210 cm −1 ∼ 921 cm −1 for neat PLA, PLAs containing 0.1 wt% and 0.3 wt% BTCA, respectively. This indicates that BTCA can accelerate both the formation of skeletal conformational-ordered structure and, especially, the 10 3 helix one. The incorporation of BTCA changes the crystallization mechanism but has no impact on the crystal form of PLA. [ABSTRACT FROM AUTHOR]