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Field experiments of nitrogen (N) treatment at five different application rates (0, 75, 150, 225, and 300 kg ha−1) were conducted under pot-seedling mechanical transplanting (PMT) in 2018 and 2019. Two high-quality and high-yielding hybrids of indica rice, Huiliangyou 898 and Y Liangyou 900, were used in this study. The N nutrition index (NNI) and accumulated N deficit (Nand), used to assess the N nutrition status in real-time, were calculated for the indica cultivars under PMT with a critical nitrogen concentration (Nc) dilution model based on shoot dry matter (DM) during the whole rice growth stage. The relationships between NNI and Nand with relative yield (RY) were determined, and accurate N application schemes were developed for hybrids indica rice under PMT. The results indicated that high application rate of N-fertilizer significantly increased the concentrations of shoot DM and N in aboveground organs during the observed stages in the two cultivars for two years (P

Electrospun poly(L)-lactide (PLLA) ultrafine fibers are a biodegradable and biocompatible scaffold, widely used in tissue engineering applications. Unfortunately, these scaffolds have some limitations related to the absence of bioactivity and antibacterial capacity. In this study, dopamine-functionalized reduced graphene oxide (rGO)/PLLA composite nanofibers were fabricated via electrospinning. The morphology and the physicochemical and biological properties of the composite nanofibers were investigated. The results indicate that incorporating rGO improves the hydrophilic, mechanical, and biocompatibility properties of PLLA nanofibers. Tetracycline hydrochloride (TC)-loaded rGO/PLLA composite nanofibers showed better controlled drug release profiles compared to GO/PLLA and PLLA nanofibrous scaffolds. Drug-loaded nanofibrous scaffolds showed significantly improved antibacterial activity against Gram-negative Escherichia coli (E. coli) and Gram-positive Staphylococcus aureus (S. aureus). Additionally, rGO/PLLA composite nanofibers exhibited enhanced cytocompatibility. Thus, it can be concluded that rGO/PLLA composite nanofibers allow the development of multifunctional scaffolds for use in biomedical applications.

The aim of this study was to observe the spatial distribution and dynamic changes of matrix metalloproteinase (MMP)-2, MMP-9, and collagen in in stent restenosis (ISR) and to explore their influence on ISR.Sixty Z type stents were implanted into the common iliac arteries of minipigs, which were divided into 10 groups (six in each group) according to euthanasia time (6 hours, and 1, 3, 7, 14, 28, 56, 84, 168, and 336 days). After the samples were harvested, haematoxylin and eosin staining, immunohistochemical staining, Western blotting, and Picrosirius red staining were performed for all groups.ISR occurred in all six minipigs in the 56 day group (percentage diameter stenosis range 71.6%-79.2%, mean ± standard deviation 75.6% ± 2.5%). The percentage diameter stenosis decreased to 38.3% ± 2.7% at 336 days (p .001). Immunohistochemical staining showed that MMP-2 and MMP-9 were strongly stained near the internal elastic lamina or in the damaged parts of the intima, around the struts and neointimal lumen surface in the ISR process. The expression of MMP-2 and MMP-9 at 56 days was significantly lower compared with their peaks (seven days and one day [p .001; p = .002], respectively). At 56 days, the collagen content reached its maximum (mean integrated optical density range 0.73-0.92, mean ± standard deviation 0.82 ± 0.09). From the 14 day group to the 336 day group, mature collagen in neointima was correlated negatively with MMP-2 (γ(36) = -0.816; p .001) and MMP-9 expression (γ(36) = -0.853; p .001). During the neointimal regression period, new collagen in neointima was positively correlated with MMP-2 (γ(24) = 0.683; p .001) and MMP-9 (γ(24) = 0.873; p .001).This study has demonstrated the spatial distribution of and dynamic changes in MMP-2, MMP-9, and collagen in ISR by simulating the process of neointima from generation to regression after stent implantation. When ISR occurred, MMP-2 and MMP-9 expression decreased and collagen content reached its maximum, which might contribute to ISR.

We evaluated the protective effect and toxicity of extracts from Mylabris phalerata Pallas by measuring the activated partial thromboplastin time, prothrombin time, venous thrombosis and acute toxicity in rats. Results showed the petroleum ether and water fractions of M. phalerata inhibited thrombosis but hardly prolonged the activated partial thromboplastin time and prothrombin time in rats. The trichloromethane fraction had obvious toxicity with an LD50 of 0.2 g/kg in vivo, and contained many cantharidin analogs (CAs) by ultra-performance liquid chromatography-quadrupole ion trap-tandem mass spectrometry (UPLC-QTRAP-MS/MS). CAs are the major potential bioactivity constituent in M. phalerata. An effective and reliable UPLC-QTRAP-MS/MS method was successfully developed to separate and identify CAs. The fragmentation patterns of five purified compounds were applied to elucidate the structure of their analogs. Thirty-four CAs were characterized or tentatively identified, eight of which are proposed to be novel compounds (13-17, 20, 21, 23), and their fragmentation patterns were investigated for the first time. Most importantly, a rapid and reliable UPLC-MS method was developed to identify the CAs of M. phalerata. This method has contributed to the discovery of most of these unknown analogs or their metabolites in M. phalerata effectively and quickly, and does not rely on limited chemical structural diversity libraries.

MnO2-decorated magnesium wire composite (MnO2-M) was fabricated via a simple hydrothermal reaction and accompanied by the calcination process (MnO2/Mn3O4-M). To clarify the optimized reaction condition of δ-MnO2 in the system, the effect of different pH, temperature and pollutant concentration of methyl orange (MO) for degradation process were investigated. Experimental results showed that MnO2-M achieves a high removal rate of 76% (2h, at 25°C) in the presence of H2O2 at pH 2.5, which is higher than that of MnO2/Mn3O4-M (54%). Moreover, reaction temperature and MO dye concentration have little effect on the degradation performance of MnO2-M. This implies the stability of the as-prepared samples and good potential in the application of wastewater treatment.

Background The diagnosis of gastric cancer mainly relies on endoscopy, which is invasive and costly. The aim of this study is to develop a predictive model for the diagnosis of gastric cancer based on noninvasive characteristics. Aims To construct a predictive model for the diagnosis of gastric cancer with high accuracy based on noninvasive characteristics. Methods A retrospective study of 709 patients at Zhejiang Provincial People's Hospital was conducted. Variables of age, gender, blood cell count, liver function, kidney function, blood lipids, tumor markers and pathological results were analyzed. We used gradient boosting decision tree (GBDT), a type of machine learning method, to construct a predictive model for the diagnosis of gastric cancer and evaluate the accuracy of the model. Results Of the 709 patients, 398 were diagnosed with gastric cancer; 311 were health people or diagnosed with benign gastric disease. Multivariate analysis showed that gender, age, neutrophil lymphocyte ratio, hemoglobin, albumin, carcinoembryonic antigen (CEA), carbohydrate antigen 125 (CA125) and carbohydrate antigen 199 (CA199) were independent characteristics associated with gastric cancer. We constructed a predictive model using GBDT, and the area under the receiver operating characteristic curve (AUC) of the model was 91%. For the test dataset, sensitivity was 87.0% and specificity 84.1% at the optimal threshold value of 0.56. The overall accuracy was 83.0%. Positive and negative predictive values were 83.0% and 87.8%, respectively. Conclusion We construct a predictive model to diagnose gastric cancer with high sensitivity and specificity. The model is noninvasive and may reduce the medical cost.

We demonstrate a novel preparative strategy for the well-controlled MnCo 2 O 4.5 @MnO 2 hierarchical nanostructures. Both δ-MnO 2 nanosheets and α-MnO 2 nanorods can uniformly decorate the surface of MnCo 2 O 4.5 nanowires to form core–shell heterostructures. Detailed electrochemical characterization reveals that MnCo 2 O 4.5 @δ-MnO 2 pattern exhibits not only high specific capacitance of 357.5 F g −1 at a scan rate of 0.5 A g −1 , but also good cycle stability (97% capacitance retention after 1000 cycles at a scan rate of 5 A g −1 ), which make it have a promising application as a supercapacitor electrode material.

During the course of search for novel and bioactive molecules of microbial origin for drug development, Stachybotrys and Memnoniella fungi generally have been found to be a rich source of novel and bioactive secondary metabolites of great importance. Results of phylogenetic analyses were in agreement that the Memnoniella is paraphyletic to Stachybotrys. Interestingly, most Memnoniella spp. were found to produce the similar chemical substances. Up until now, almost 200 secondary metabolites belonging to diverse structural types of trichothecene, triprenyl phenol, diterpenoid, isochroman, polyketide, cochlioquinone and cyclic peptide have been discovered. Most of these fungal metabolites were reported to possess several interesting biological activities, such as disruption of the complement system, inhibition of TNF-α release, endothelin receptor antagonism, anti-influenza A virus, antimalarial, inhibition of avian myeloblastosis virus protease, cholesterol esterase, tyrosine kinase, farnesyl-protein transferase, squalene synthase and human heart chymase as well as stimulation of plasminogen, fibrinolysis, thrombolysis. This review summarizes the research on the isolation, structure elucidation, structural diversity, and bioactivities of the Stachybotrys and Memnoniella fungal secondary metabolites reported up to the year of 2014, and then highlights some bioactive compounds as well as their mechanisms of action and structure–activity relationships.

The microbiological transformation of the triterpene nigranoic acid (3,4-secocycloarta-4(28),24(Z)-diene-3,26-dioic acid) (1) to 3,4-secocycloarta-4(28),17(20),24(Z)-triene-7β-hydroxy-16β,26-lactone-3-oic acid (2) and 3,4-secocycloarta-4(28),17(20)(Z),24(Z)-triene-7β-hydroxy-16β-methoxy-3,26-dioic acid (3) by the freshwater fungus Dictyosporium heptasporum YMF1.01213 has been demonstrated. The structures of the biotransformation products were determined by spectroscopic and MS analyses. Compound 2, characterized by the presence of a formed C-16/C-26 ester bridge, provided a novel nine-membered lactone ring structural skeleton for 3,4-secocycloartane triterpenoid derivatives. In addition, Compounds 1-3 exhibited weak anti-HIV activity in vitro. Compounds 2 and 3 were reported for the first time as natural product derivatives.

Six new dibenzo[b,e]oxepinone metabolites, chaetones A-F (1-6), as well as three known compounds, 1-hydroxy-6-methyl-8-hydroxymethyl-xanthone (7), citreorosein (8), and emodin (9), were obtained from a freshwater-derived fungal strain Chaetomium sp. YMF 1.02105. Their structures were established on the basis of extensive spectroscopic data analysis and comparison with spectroscopic data reported. Compounds 1-6 are further additions to the small group of dibenzo[ b,e]oxepinones represented by arugosins A-H. Compounds 1-7 were tested for their cytotoxic activities against A549, Raji, HepG2, MCF-7, and HL-60 cell lines. The results showed that compound 3 had significant cytotoxicitywith IC50 values of 1.2, 1.8, 1.9, 2.3, and 1.6 mu g/mL, respectively, against the five cancer cell lines. All compounds showed modest antimicrobial activity against Staphylococcus aureus (ATCC 6538) in standard disk assays.

Eleven new monoterpenoids including three 1-methyl cantharimide-type derivatives (1–3), five 1,2-dimethyl cantharimide-type derivatives (4, 5, 7–9), and three 1-hydroxymethyl-2-methyl cantharimide-type derivatives (10–12), together with seven known cantharimides (6, 13–18), were isolated from Mylabis phalerata Palla. The planar structures and absolute configurations of compounds 1–14 were fully elucidated on the basis of spectroscopic analysis, ECD spectra, single-crystal X-ray diffraction analysis, and chemical methods. Compounds 6, 15, 16, and 18 were found to be potent inhibitors of HBV virus, with IC50 values of 62, 42, 58, and 19 μM.

Two new metabolites were obtained by microbial transformation of the triterpene nigranoic acid (3,4-secocyloarta-4 (28), 24 (Z)-diene-3,26-dioic acid), (1) in the culture of Trichoderma sp. JY-1, a fungus obtained from the branches of Kadsura angustifolia. Their structures were established as 15α, 16α-dihydroxy-3,4-secocyloarta-4 (28), 17 (20), 17 (E), 24 (E)-triene-3,26-dioic acid (2) and 16α, 20α-dihydroxy-18 (13 → 17β) abeo-3,4-secocyloarta-4 (28), 12 (13), 24 (Z)-triene-3,26-dioic acid (3) by analysis of NMR and MS data and by analogy with the data for the substrate nigranoic acid (1). Compound 2 was found to possess an unusual 17(20), 17 (E)-ene structure while compound 3 featured an unprecedented 18(13 → 17β)-abeo-secocyloarta skeleton. Additionally, compounds 1–3 showed weak anti-HIV activity with EC50 values of 10.5, 8.8 and 7.6 μg/mL, therapeutic index values (CC50/EC50) of 8.48, 9.12 and 10.1, respectively.

Ten compounds were isolated from Mylabris phalerata by using preparative HPLC and column chromatography over MCI gel. On the basis of physical-chemical properties, NMR and MS data analysis, the compounds were identified as 5'-[(1 R,2 R,3 S,6R)-1-hydroxymethyl-2-methyl-3,6-epoxycyclohexane-1,2-dicarboximide]- ethyl-2'-methyl-2'-butenoate (1),cantharidin (2), cyclo-(L-Pro-L-Ala) (3), cyclo-(R-Pro-R-Leu) (4), cyclo-(S-Pro-R-Leu) (5), cyclo-(D-Pro-L-Tyr) (6), indole-3-aldehyde (7), 3-indoleacetic acid (8), valerolactam (9), and 4-hydroxyphthalid (10).Compound 1 was a new compound, and compounds 2-10 were obtained from this genus for the first time. Compounds 1-9 were subjected to cytotoxic activity on HCT-116, HepG2, BGC-823, NCI-H1650, A2780 cell lines, and only compound 2 showed inhibitory effect on all cancer cell lines.

AZ31 wrought alloys at as-cast state with different microcontent calcium and strontium was studied by optical microscopy, X-ray diffraction, scanning electron microscopy and energy dispersive X-ray analysis. The study shows that the primary dendrite spacing and the secondary dendrite arm spacing can be refined significantly by Ca or Sr element. At 0.5wt.% Sr and 1.8wt.% Ca, the best refinement effect is fulfilled, its primary dendrite spacing and secondary dendrite arm spacing decreased from 292μm to 87μm. The Al4Sr intermetallic compound is observed at grain boundaries When Sr was added. The Al4Sr disappears after Ca added, a new ternary intermetallic compound (Mg, Al)2Ca presents. The addition of Sr and Ca can cause microhardness increasing.

Four new cycloartane triterpenoids, angustific acid A (1), angustific acid B (2), angustifodilactone A (3) and angustifodilactone B (4) were isolated from the branches of Kadsura angustifolia together with six known compounds, micranoic acid B (5), nigranoic acid (6), schisandrin (7), schisantherin D (8), interiotherin B (9), schisantherin B (10). Their structures were established on the basis of extensive spectroscopic data analyses and comparison with spectroscopic data reported. Compound 1, characterized by the presence of a C-16/C-17, C-20/C-21 conjugated diene and a C-1/C-7 ester bridge formed in rings A and B, provided a novel structural skeleton for 3,4-secocycloartane triterpenoid derivatives. In addition, the anti-HIV activities of these compounds were determined in infected C8166 cells, and it was found that angustific acid A (1) exhibited the most potent anti-HIV activity with an EC(50) value of 6.1 μg/mL and a therapeutic index of more than 32.8.

The microstructure, mechanical properties and damping capacity of ZK60-xY (x=0, 1.5%, 2.5%, 4.0%, mass fraction) magnesium alloys were investigated by using the optical microscope (OM), X-ray diffractometer (XRD), universal tensile testing machine and dynamic mechanical analyzer (DMA). The mechanisms for damping capacity of referred alloys were discussed by Granato-Lucke theory. The results show that Y additions remarkably reduce grain size (the average grain size is 21.6, 13.0, 8.6 and 4.0 μm, respectively), and the tensile properties are enhanced with grain refining (the yield tensile strength increases to 292 MPa from 210 MPa and ultimate tensile strength increases to 330 MPa from 315 MPa). For the ZK60-xY (x=0, 1.5%, 4.0%) alloys, the damping capacity decreases with the increase of Y content. However, for the ZK60-xY (x=2.5%) alloy, the damping capacity improves abnormally, which is possibly related to the formation of Mg3Y2Zn3 (W) FCC phase in this alloy.

Titanium dioxide (TiO2) and silicon dioxide (SiO2) coating deposition were respectively performed by the dip coating technique on magnesium AZ31 alloy with extrusion surface finishes. The anticorrosive effect of different sol-gel coating was compared by measuring the weight loss when the samples were immerged in atmosphere, acetic acid aqueous solution with pH 5.0, distilled water with pH 6.4, aqueous 5% sodium chloride solution with pH 7.0. Morphological and structural characteristics of the coatings were analyzed by scanning electron microscopy (SEM), and semi quantitative analyses of the composition were performed by energy dispersive X-ray analysis (EDX) line scans. The results show that the anticorrosion properties of magnesium alloy with SiO2 or TiO2 are magnificently impactful in atmosphere. The anticorrosion effect of TiO2 coating is much preferable in a relatively strong acid environment.

The structural organization of natural liver is instrumental in the multifunctionality of hepatocytes, and mimicking these specific architectures in tissue-engineered scaffold plays an important role in the engineering of an implantable liver equivalent in vitro. To achieve this goal, we have developed a novel fabrication process to create chitosan–gelatin hybrid scaffolds with well-organized architectures and highly porous structures by combining rapid prototyping, microreplication and freeze–drying techniques. The scaffolds obtained not only have analogous configurations of portal vein, central vein, flow-channel network and hepatic chambers, but also have high (>90%) porosity, with the mean pore size of 100 μm. Swelling and degradation studies showed that the scaffold has excellent properties of hydrophilicity and biodegradability. A hepatocyte culture experiment was conducted to evaluate the efficiency of the well-defined chitosan–gelatin scaffold in facilitating hepatocyte growth in the inner layer of the scaffold in vitro. Scanning electron microscopy and histological analysis showed that hepatocytes could form large colonies in the predefined hepatic chambers, and these cavities could the completely filled with hepatocytes during 7 day culture. Albumin secretion and urea synthesis further indicated that the well-organized scaffolds were more suitable for hepatocyte culture.

The fabrication process for a novel three-dimensional (3D) chitosan/gelatin scaffold with predefined multilevel internal architectures and highly porous structures is presented combining solid freeform fabrication (SFF), microreplication and lyophilization techniques. The computer model of the scaffold is designed with biological data such as branching angle in liver vascular cast incorporated. Stereolithography (SL), known as a SFF technique, is utilized to build the resin mould, based on which poly-dimethylsilicone (PDMS) mould is produced by microreplication. The chitosan/gelatin hybrid solution is then cast onto the PDMS mould for pre-freeze and the monolayer porous structures with organized internal morphology are produced upon lyophilization. The 3D scaffold can be constructed via stacking these monolayer structures. The properties of porous structure, such as porosity, pore size and micromorphology as well as wall thickness, were investigated. Scanning electron microscopy (SEM) demonstrated that the scaffold possesses multilevel organized internal morphologies including vascular systems (portal vein, artery and hepatic vein) and parenchymal component (hepatocyte chamber). These organized structures enable orderly arrangement of hepatocyte and hepatic nonparenchymal cells and co-culture in the same 3D scaffold to guide liver regeneration in a controlled manner. Cell culture experiment in vitro showed that hepatocytes perform better in the well-defined chitosan/gelatin scaffold than in porous scaffold. This approach makes it flexible to investigate the relationship between internal scaffold microstructure and hepatocyte behavior in vitro. It also provides a new way to fabricate complex 3D scaffold using various natural biomaterials for vital organ engineering.

Four new cycloartane triterpenoids angustifodilactone A and B (I), angustific acid A (II), and angustific acid B (III), are isolated from the branches of the title plant together with six known compounds.

Activated carbons (ACs) were prepared from lignin as the char precursor by means of the KOH activation method. The influence of KOH char mass ratio (K/C) on the pore properties and morphology of ACs, which play an important role on the electrochemical behavior of AC electrodes, were investigated by scanning electron microscope (SEM) and nitrogen adsorption technique. The results showed that K/C has a great effect on the pore properties including the specific surface area (S BET ), total pore volume (V t ) and micro pore volume (V mic ). The S BET and V t of ACs reached a maximum (1506 m2/g and 0.795 cm3/g) as the K/C was equal to 3. With the aim of studying, the influence of K/C on the electrochemical properties of AC electrodes was investigated by cyclic voltammetry, constant current charge-discharge and electrochemical impedance spectroscopy. The specific capacitance of AC electrodes reached a maximum (267.8 F/g measured at a current density of 50 mA/g) as K/C was equal to 3, even the specific capacitance remained the capacitance retention ratio of 83.9% after 2000 cycles, which was attributed to high specific surface area, appropriate pore distribution and low electronic resistance of ACs.

In the PDF file of the paper by Y. B. Tao et al. [Phys. Status Solidi C 6, S317 (2009)], published online 7 May 2009, a wrong image was loaded: in place of Fig. 2, inadvertently Fig. 1 was shown again. This Erratum displays Figs. 1 and 2 properly. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Using the surface of poly (sulfone) hollow fiber membrane segments as grafted layer, the hydrophilic acrylamide chain was grafted on by UV-photoinduced grafting polymerization. The gained improvement of surface wettability for the modified membrane was tested by measuring the contact-angle as well as FTIR spectra. Then correlation between the hydrophilic ability of support material and the biofilm adherence ability was demonstrated by comparing the pollutant removal rates from urban wastewater via two identical lab-scale up-flow biological aerated filters, one employed the surface wettability modified poly (sulfone) hollow fiber membrane segment as biofilm carrier and the other employed unmodified membrane segment as biofilm carrier. The experimental results showed that under the conditions of influent flux 5 L/h, hydraulic retention time 9 h and gas to liquid ratio (G/L) 10:1, the removal rates of chemical oxygen demand (COD) and ammonium nitrogen (NH4(+)-N) for the modified packing filter and the unmodified packing filter was averaged at 83.64% and 96.25%, respectively, with the former filter being 5%-20% more than the latter. The effluent concentration of COD, NH4(+)-N and turbidity for the modified packing filter was 25.25 mg/L, 2 mg/L and 8 NTU, respectively. Moreover, the ammonium nitrogen removal performance of the filter packing the modified PSF was compared with the other bioreactor packing of an efficient floating medium. The biomass test indicated that the modified membrane matrixes provided better specific adhesion (3310-5653 mg TSS/L support), which gave a mean of 1000 mg TSS/L more than the unmodified membrane did. In addition, the phenomenon of simultaneous denitrification on the inner surface of the support and nitrification on the outer surface was found in this work.

Removal of inorganic nitrogen (inorganic-N) from toilet wastewater, using a pilot-scale airlift external circulation membrane bioreactor (AEC-MBR) was studied. The results showed that the use of AEC-MBR with limited addition of alkaline reagents and volumetric loading rates of inorganic-N of 0.19–0.40 kg inorganic-N/(m3.d) helped achieve the desired nitrification and denitrification. Furthermore, the effects of pH and dissolved oxygen (DO) on inorganic-N removal were examined. Under the condition of MLSS at 1.56–2.35 g/L, BOD5/ammonia nitrogen (NH4+-N) at 1.0, pH at 7.0–7.5, and DO at 1.0–2.0 mg/L, the removal efficiencies of NH4+-N and inorganic-N were 91.5% and 70.0%, respectively, in the AEC-MBR. The cost of addition of alkaline reagent was approximately 0.5–1.5 RMB yuan/m3, and the energy consumption was approximately 0.72 kWh/m3 at the flux of 8 L/(m2.h).