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In this research, a novel green mechanochemical dry gel conversion method (MDGC) is reported to obtain submicron-sized Ti-rich MWW zeolite. First, titanium and silica sources were milled under milder conditions in a planetary ball mill to construct the uniform SiO2-TiO2 composite powders with higher Ti contents. Subsequently, submicron-sized Ti-rich MWW zeolite powder was prepared via dry gel conversion (DGC) route using the obtained composite under mixed steam environment consisting of water and piperidine. The physicochemical properties of the SiO2-TiO2 composites before and after calcination and corresponding Ti-MWW-MDGC were investigated by XRD, UV–Vis, FT-IR, SEM, XRF, and N2 absorption-desorption. Moreover, Ti-MWW (30)-MDGC exhibited a superior catalytic activity during epoxidation with H2O2 compared with the traditional DGC method, and the conversion of 1-hexene increased from 4.2% to 26.3%. The MDGC method is a promising approach for the green production of various zeolites with higher heteroatom contents, such as TS-1, Ti-Beta and Sn-MWW, etc.

TGase treated soy protein isolate (SPI) was confirmed to improve the survival of Lb. bulgaricus CICC 6047 subjected to spray drying. The viability of this strain increased from 70.69 % to 86.01 % due to elevating thermal stability. The smoother bacterial cell surface was observed by TGase treated SPI. TGase treatment changed the secondary conformation of SPI, having α-helical structure increased. Chemical bonds (hydrogen bond, CN bond, NH bond) proved the enzyme-modified SPI to have enhanced resistance to heat. The addition of TGase treated SPI allowed other LAB strains to tolerate the spray drying better. Their survival percentage after spray drying was 83.44 % for Le. mesenteroides CICC 6055, 80.64 % for Lb. acidophilus NCFM, 87.79 % for B. animalis BI-03 and 87.02 % for Lb. plantarum CICC 6009, respectively. The good survival of the selected LAB strains from TGase treated SPI powders was observed during storage of 8 weeks at 4 °C.

A hierarchical nanosized Ti-BEA zeolite was prepared via a green steam-assisted conversion (SAC) method taking inorganic titanium source as the raw material. Neither aluminum source nor hydrofluoric acid was required, instead, only a bit of template agent (TEAOH/SiO2 = 0.2) and 2 days period were sufficient, much less than that reported (TEAOH/SiO2 ≥ 0.55, 7–14 days). Comprehensively, the role of seeds, alkali ions, and ion exchange on the physicochemical properties of Ti-BEA products were investigated via a series of characterization. Innovatively, the tetracoordinated Ti active sites could be directly constructed by a simple ion exchange process instead of conventional acid washing; furthermore, the mechanism of ion exchange inducing Ti coordination transformation was also proposed to guide other titanosilicate zeolites. Excellent Ti active sites, surface properties, and textural properties endowed the Ti-BEA catalyst with excellent activity over cyclohexene epoxidation, while its synthesis procedure and cost were far better than reported.

In this work, we construct zwitterionic multilayers on poly(vinyl alcohol) (PVA) thin-film nanofibrous composite (TFNC) substrate via a facile surface engineered layer-by-layer (LBL) assembly of poly (sulfobetaine methacrylate) (PSBMA) and tannic acid (TA, a polyphenol), which endowed the modified membranes with multifunctionality for filtration of proteins and dyes and potential biomedical application. Characterizations of surface chemical structure and morphology of the modified membranes confirmed the successful zwitterionic self-assembly modification. The LBL-assembled membranes showed superior separation performance for filtration of proteins and dyes. Especially when the number of TA/PSBMA bilayer was 6, the PVA-6BL-M possessed high permeate flux (311.7 Lm−2 h−1) and excellent rejection (99.9%) for 0.1 g/L Direct Red 80 solution at 0.6 MPa. After being covered more TA/PSBMA bilayers, the LBL-assembled membranes could not only sieve smaller molecules of proteins and dyes well, but also exhibit better anti-biofouling properties (higher water flux recovery ratio, negligible irreversible fouling and the less BSA, E. coli and S. aureus bacteria adsorption). In addition, the LBL-assembled membranes presented excellent blood compatibility (greatly reduced platelet adhesion, significantly increased clotting time and lower hemolysis ratio), which indicated great potential for biomedical application. This work provided a facile and efficient method for designing a multifunctional TFNC membrane for water treatment and biomedical engineering.

Polymeric hemodialysis (HD) membranes with limited porosities, tortuous pores, and broad pore size distributions suffer from a trade-off between permeability-i.e., how fast toxins pass through the membranes-and selectivity-i.e., to what extent necessary proteins are retained. Here, a novel thin-film nanofibrous composite (TFNC) membrane, composed of an electrospun polyacrylonitrile (PAN) nanofibrous support layer and a chemically cross-linked polyvinyl alcohol (PVA) separation layer filled with heparin functionalized multi-walled carbon nanotubes (Hep-g-pMWCNTs), was demonstrated for efficient and safe HD application. Combining dialysis simulation experiments and pore-flow model, we demonstrated that the formation of free nanogaps at the interface between Hep-g-pMWCNTs and PVA matrix provided additional directional nanochannels for toxins to transport. The membranes showed efficient toxins removal without sacrificing selectivity (with the urea clearance of 88.2%, lysozyme clearance of 58.6%, and bovine serum albumin retention of 98.4% in a 4 h simulating dialysis). Especially, the efficiency in removing middle molecule toxins increased obviously compared with the values reported to date. Besides, the membranes exhibited excellent hemocompatibility: high resistance to protein adsorption, suppressed platelet adhesion, favorable anticoagulant activity, limited hemolysis ratio, and low complement activation. These facts suggested that the Hep-g-pMWCNTs/PVA/PAN TFNC membranes with superior comprehensive performances presented great potential for HD application.

In order to improve the utilization of tea seed, microwave/ultrasonic assisted extraction (MUAE) was firstly applied for the extraction of tea seed oil (TSO). The factors with significant effects on oil yield were screened by Plackett-Burman design and then optimized by Box-Behnken design. The oil yield of 31.52% was obtained under optimum extraction conditions of microwave power 440 W, ultrasonic power 550 W, extraction time 38 min, solvent to material ratio 8 mL/g, extraction temperature 70 ℃ and particle size

Background: In the process of carrying small forgings and other materials, the trajectory error of the 6-degree of freedom light-load collaborative robot will lead to the deviation of forgings placement position. The kinematics analysis and calibration of 6-degree of freedom light load collaborative robot are performed to solve the problem of trajectory error. Methods: The quaternion and cubic spline interpolation methods are adopted to plan the trajectory of the 6-degree of freedom light load collaborative robot. Based on the kinematic error model, the least squares estimation method is adopted to estimate the parameter error of the robot's connecting rod, and the parameter compensation values of each joint are obtained. Results: The kinematic calibration experiment shows that the coordinates of the robot end center are basically consistent with the actual coordinates after compensation, which verifies the rationality of the kinematic model and calibration method. Conclusions: The study lays the theoretical foundation for the trajectory error correction of the light load collaborative robot.

In order to develop advanced hemodiafiltration membrane with favorable biocompatibility and efficient dialysis performance, novel thin film nanofibrous composite (TFNC) ultrafiltration (UF) membranes consisting of sulfonated poly(vinyl alcohol) (s-PVA) blended PVA hydrogel barrier layer and electrospun polyacrlonitrile (PAN) nanofibrous supporting layer were designed and fabricated by combining electrospinning and conventional surface coating techniques. The mesh sizes of hydrogel network of s-PVA/PVA barrier layer could be tuned by varying the blending content of s-PVA. The optimized s-PVA/PVA TFNC UF membrane (S-P-TFNC-1-3) possessed high pure water flux up to 380 L m−2 h−1 bar−1 with high bovine serum albumin (BSA) rejection (>90%). Besides, the introduction of s-PVA into the hydrogel barrier layer endowed the TFNC membranes with enhanced hydrophilicity, antifouling property and biocompatibility (decreased protein adsorption, prolonged clotting time, suppressed platelet adhesion, lower hemolysis ratio and more benefits for cell proliferation) due to the presence of sulfonic groups. The dialysis simulation experiment results of S-P-TFNC-1-3 showed that 84.2% of urea and 60.9% of lysozyme were cleaned and over 95% of BSA was retained after 4 h dialysis process. Especially, the removal of middle-molecule uremic toxin was more efficient than conventional hemodialysis membranes reported so far, and high retention of big proteins was achieved simultaneously. This work exposes a window of opportunity for modified PVA TFNC membranes in blood purification applications.

Many in vitro studies support the general idea that vitamin D plays a protective role against cancer. Increased doses of vitamin D dietary supplements have been widely used for the potential anticancer benefits of vitamin D. However, despite substantial epidemiological research, there are no clear conclusive data to support the use of vitamin D as a cancer preventive or treatment agent. In the, herein, reported study, we checked the effects of 1,25-dihydroxyvitamin D3 concentrations on the expression level of the vitamin D receptor (VDR) and cell cycle-related proteins CDKN1A (p21) and CDK1 in pancreatic cells and Panc-1 pancreatic cancer (PC) cells. We found that VDR, CDKN1A, and CDK1 were upregulated by an increase in 1,25-dihydroxyvitamin D3 concentration in normal pancreatic cells but not in the advanced cancer cell line Panc-1 from poorly differentiated metastatic PC cells. A further increase in 1,25-dihydroxyvitamin D3 concentration above the physiological range significantly downregulated the expression of VDR, indicating that VDR is modulated by VDR levels to maintain normal functioning during dramatic variations in vitamin D concentration. By increasing the level of cell cycle inhibitory and promoting proteins p21 and CDK1, vitamin D theoretically has both preventive and promoting effects on pancreatic cell division.

In this study, Microwave-assisted extraction (MAE) was firstly applied in extraction of tiger nut oil (TNO). Parameters of MAE were optimized by response surface methodology. The optimum extraction conditions were a mixture of petroleum ether (boiling range 60–90 °C) and acetone (2:1, v/v), microwave power 420 W, temperature 75 °C, liquid to solid ratio 7.0 mL/g and time 55 min, which could obtain yield of 24.12%. The fatty acid composition of oil by MAE was similar to that of oil by Soxhlet extraction (SE), whereas oil by MAE exhibited superior physicochemical properties and oxidation stability. Moreover, oil by MAE had a higher content of total phenolic, α-tocopherol, β-carotene, phospholipids and phytosterols. Scanning electron microscopy demonstrated that structural disruption of tiger nut caused by microwave irradiation was the main reason for rapid extraction. So MAE could be a good alternative for extraction of TNO.

Microwave-assisted extraction (MAE) of oil from silkworm pupae was firstly performed in the present research. The response surface methodology was applied to optimize the parameters for MAE. The yield of oil by MAE was 30.16% under optimal conditions of a mixed solvent consisting of ethanol and n-hexane (1:1, v/v), microwave power (360W), liquid to solid ratio (7.5/1mL/g), microwave time (29min). Moreover, oil extracted by MAE was quantitatively (yield) and qualitatively (fatty acid profile) similar to those obtained using Soxhlet extraction (SE), but oil extracted by MAE exhibited favourable physicochemical properties and oxidation stability. Additionally, oil extracted by MAE had a higher content of total phenolic, and it showed stronger antioxidant activities. Scanning electron microscopy revealed that microwave technique efficiently promoted the release of oil by breaking down the cell structure of silkworm pupae. Therefore, MAE can be an effective method for the silkworm pupal oil extraction.

Ethnopharmacological relevance Ginkgo biloba leaves and Panax ginseng are Chinese medicine commonly used in combination for cerebral disease. Aim of the study To investigate the effect of standard extract of Ginkgo biloba leaves (EGb) on facilitating brain uptake of ginsenoside and its underlying mechanisms. Materials and methods The increasing uptake of ginsenosides in the brain of rats by EGb were detected by LC–MS/MS analysis. Evans blue and FITC-dextran leakage were determined to evaluate blood-brain barrier (BBB) permeability in vivo. Transendothelial electrical resistance (TEER) and Na–F penetration rate were measured with a co-culture of the human cerebral microvascular endothelial cell line (hCMEC/D3) and human normal glial cell line (HEB) in vitro BBB model. WB were used to analyzed the expression of BBB tight junctions (TJs) related protein (ZO-1, Occludin, Claudin-3, p-ERM, and p-MLC), ultrastructure of TJs was determined by transmission electron microscope. Results LC–MS/MS analysis demonstrated that EGb could improve brain uptake of ginsenoside Rg1, Re, Rd and Rb1. In vivo study showed that, BBB permeability was significantly increased after EGb administration, evidenced by the markedly increased penetration of FITC-dextran and Evans Blue into the mice brain parenchyma. In the in vitro BBB model, reduced TEER and increased Na–F penetration rate was observed in EGb group, which was associated with alteration of TJs ultrastructure. Furthermore, the expression of p-ERM and p-MLC in hCMEC/D3 as well as mice brain microvessels were significantly upregulated, but no significant change on the expression of TJs proteins (ZO-1, Occludin and Claudin-3). Moreover, the effect of EGb on in vitro BBB permeability and ERM, MLC phosphorylation was counteracted by DPCPX, an A1 adenosine receptor (A1R) antagonist. Conclusions EGb might induce ERM/MLC phosphorylation and increase the cell-cell junction gaps to cause a reversible increase of the BBB permeability via A1R signaling pathway. Our results may contribute to better use of EGb in the treatment of brain diseases.

Membrane structure design is critical for the development of high-performance hemodialysis membranes. Here, a thin-film nanofibrous composite (TFNC) membrane, consisting of a two-tier composite structure, i.e., an ultrathin hydrophilic separation layer of chemically cross-linked polyvinyl alcohol (PVA), and an electrospun polyacrylonitrile (PAN) nanofibrous supporting layer, was demonstrated as the hemodialysis membrane for the first time. The optimized PVA/PAN TFNC membrane exhibited high permeability (~ 290.5 L/m 2 h at 0.1 MPa) and excellent selectivity which should be attributed to its unique structure with ultrathin separation layer and highly porous supporting layer. In addition, the TFNC membrane also possessed excellent overall mechanical properties, good hydrophilicity and comparable hemocompatibility properties (protein adsorption, platelet adhesion, complement activation, hemolysis ratio). The hemodialysis simulation experiments on optimized TFNC membrane showed that 82.6% of urea and 45.8% of lysozyme were cleaned and 98.8% of bovine serum albumin (BSA) was retained. The TFNC membranes exhibited excellent hemodialysis performances, especially for the middle-molecule uremic toxin removal, which was more efficient than conventional hemodialysis membranes reported so far, suggesting PVA/PAN TFNC membranes as promising alternatives for hemodialysis applications.

In order to reveal the performance of mixture in Organic Rankine Cycle (ORC), this paper presents the performance of ORC using hot air as heat resource. The zeotropic mixture fluids studied are R227ea/R245fa, Butane/R245fa and RC318/R245fa. The first law efficiency, the second law efficiency, exergy loss distributions and net power output of zeotropic mixture fluids are calculated and compared with corresponding pure fluids. By using the counter flow heat exchangers, the system's economic performance is analyzed based on the net power output per unit UA. The result indicates that better thermal performance can be achieved when the temperature difference of cooling water is near the temperature glide of zeotropic mixture in the condenser; cycle efficiency, exergy efficiency and net power output increase compared to corresponding pure fluid cycles, but the net power output per unit UA decreases; in other words, the economic performance of this system becomes worse in some degree.

Hemodialysis membranes are critical components for hemodialysis process. Herein, we demonstrate a new kind of hemodialysis membrane based on polyacrylonitrile (PAN) electrospun scaffold and heparin-poly(vinyl alcohol) (heparin-PVA) hydrogel coating. Manipulation of coating solution rheology by control of heparin content enabled the creation of membranes with sub-micron ridged surface topography. The results of attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectra confirmed that heparin was covalently incorporated in the hydrogel layer; meanwhile, the scanning electron microscopy (SEM) and atomic force microscopy (AFM) images gave clear evidence that the fabricated membranes had typical sub-micron ridge structure. The results revealed that the sub-micron ridged surface topography and heparin chemical modification synergistically endowed the membranes with excellent permeability, protein antifouling properties, anticoagulant activity, cytocompatibility, and dialysis performances. Especially, when the heparin/PVA weight ratio was 20%, the water flux of the membrane was 371.8 L/m2h. Its urea clearance was 86 mL/min, lysozyme clearance was 60 mL/min, and bovine serum albumin clearance was as less as 5.5 mL/min.

Biomacromolecules and their assemblies exhibit the great potential for biomimetic construction of novel and functional nanomaterials. In this work, sulfated silk nanofibrils (SSNFs) were firstly prepared with special designed sulfated silk fibroin molecule by a facile self-assembly technique, which were incorporated into the poly (vinyl alcohol) (PVA) hydrogel. Then they were together coated on the electrospun polyacrlonitrile (PAN) nanofibrous scaffold to fabricate a novel PVA/SSNFs/PAN thin film nanofibrous composite (TFNC) membranes for hemodiafiltration. Combining the results from filtration and hemodiafiltration tests, it could be deduced that the formation of nanogaps between PVA matrix and SSNFs provided more nanochannels for water and uremic toxins to transport rapidly through the functional layer. Especially the incorporation of SSNFs into PVA hydrogel layer endowed PVA/SSNFs TFNC hemodiafiltration membranes with rapid mid-molecule toxins removal channels. PVA/SSNFs-5 could clear 65.7% of lysozyme, also maintaining 85.0% clearance of urea and 94.7% interception of BSA after 4 h of dialysis. In addition, the blood compatibility of PVA/SSNFs TFNC membranes was also enhanced after the introduction of biomimetic SSNFs due to the heparin-like structure of sulfated silk fibroin (SSF). The biomimetic assembly route demonstrated here represents a green and efficient way for designing various functional nanomaterials in bio-nanotechnologies.

In order to increase the utilization of cherry seeds, ultrasonic-microwave assisted aqueous enzymatic extraction (UMAAEE) was used to extract cherry seed oil. Parameters of UMAAEE were optimized by Plackett-Burman design followed by Box-Behnken design. The oil recovery of 83.85 ± 0.78% was obtained under optimum extraction conditions of a 2.7% concentration of enzyme cocktail comprising cellulase, hemicellulase and pectinase (1/1/1, w/w/w), ultrasonic power of 560 W, microwave power of 323 W, extraction time of 38 min, extraction temperature of 40 °C, enzymolysis temperature of 40 °C, pH of 3.5, liquid to solid ratio of 12 mL/g, enzymolysis time of 240 min and particle size less than 0.425 mm. There were no significant differences in the fatty acid compositions of cheery seed oil by UMAAEE and Soxhlet extraction, and oil by UMAAEE possessed superior physicochemical properties and higher content of bioactive constituents. Scanning electron microscopy illustrated that enzyme hydrolysis and ultrasonic-microwave treatment causing the structural degradation of cherry seed was the main driving force for extraction. In this study, all results suggest that UMAAEE is an effective method to extract cherry seed oil.

This paper deals with a rigid formation control problem of n agents moving in the plane, where each agent is required to maintain a nominated distance from its neighbors, and each agent is described by a double integrator. A globally stable formation control strategy is designed to drive the multi-agent systems to a desired rigid formation using the integrator backstepping technique and the adaptive perturbation method. Therefore, the proposed control law can guarantee that the equilibrium set of the overall system is unique, and all agents' velocity converge to a common value without collision between each communicating agents. Simulation results are provided to illustrate the effectiveness of the control algorithm.

Objective: To investigate the protective effect of Polygonum multiflorum extracts (EPM) on SH-SY5Y cells treated with MPP+. Methods: SH-SY5Y cells were first exposed to various doses of EPM, and then treated with MPP+. The cell viability was detected with MTT assay, cell morphology was observed with microscope by Hoechst33258 staining, the level of glutathione (GSH), Malondialdehyde (MDA) and the activity of Lactate dehydrogenase (LDH) were measured with UV spectrophotometer. Reactive oxygen species (ROS) and the mitochondrial membrane potential were observed with fluorescence microscope. The expression of p-JNK and Caspase 3 was analyzed by Western Blot. Results: After 0.5 mmol/L MPP+ treatment for 48 h, the viability of SH-SY5Y cells was decreased to 44.7% (VS. control group), the shrunk cell body and nuclear condensation were observed. Compared with control group, the activity of lactate dehydrogenase (LDH), the level of malondialdehyde (MDA) and reactive oxygen species (ROS) and the expression of p-JNK and Caspase 3 were increased significantly in MPP+ treated SH-SY5Y cells, whereas the level of GSH and the mitochondrial membrane potential was reduced significantly in MPP+ treated group. However, pretreatment with EPM (at the concentration of 5, 25 and 100 mg/L) 4 h prior to being exposed to MPP+ rescued the cell viability of SH-SY5Y cells, and restored the cell morphological features in a dose-dependent manner. The increasement of lactate dehydrogenase (LDH), malondialdehyde (MDA) and reactive oxygen species (ROS) and the expression of p-JNK and Caspase 3 induced by MPP+ were also inhibited significantly by pretreatment with EPM. Exposure to EPM also blocked the reduction of the GSH level and the mitochondrial membrane potential induced by MPP+ in SH-SY5Y cells. Conclusion: Our results suggested that the EPM was able to protect the SH-SY5Y cells against the damage induced by MPP+, with the mechanism involved in resisting the oxidative stress.

Although marketing researchers and sociologists have recognized the large impact of life stage on consumer's purchasing behaviors, existing recommender systems have not taken this impact into consideration. In this paper, we found obvious correlation between life stage and purchasing behavior in many E-commerce categories. For example, a mum may look for different suitable products when her baby is at different ages. Motivated by this, we introduce the conception of life stage into recommender systems and propose to predict a user's current life-stage and recommend products correspondingly. We propose a new Maximum Entropy Semi Markov Model to segment and label consumer life stage based on the observed purchasing data over time. In the mom-baby product category where the life stage transition is deterministic, we develop an efficient approximate solution using large scale logistic regression and a Viterbi-like algorithm. We also propose a Gaussian mixture model to efficiently handle multi-kids life stage prediction problem. We integrate the life stage information predicted into the recommender system behind the largest online shopping website taobao.com. Both offline and online experiments demonstrate the effectiveness of the proposed life-stage based recommendation approach.

Few synthetic elaborations of the Michael adducts obtained are also reported, including syntheses of 2,3-disubstituted cyclic ethers, α-substituted lactones and analogues of the antidepressant drug venlafaxine.

A globally stable formation control strategy that drives multi-robot systems to a desired rigid formation is proposed in this paper. The proposed control law is based on the adaptive perturbation method, and it can guarantee that the equilibrium set of the overall system is unique, which is exactly the desired formation set. Simulation results are provided to illustrate the effectiveness of the control algorithm.