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In this study, reflectance spectroscopy was used to achieve rapid and non-destructive detection of amylase activity and moisture content in rice. Since rice husk can interfere with spectral measurements, spectral data transformation was used to remove the husk interference. Reflectance spectra of rice were transformed by direct standardization, convolutional autoencoder network, and kernel regression (KR). Then, random frog and elliptical envelope were adopted to select effective wavelengths, and partial least squares regression (PLSR) and support vector regression were used to establish analysis models. The optimal transformation was from KR, and PLSR and effective wavelengths of the transformed spectra obtained excellent performance with coefficient of determination of test of 0.6987 and 0.8317 and root-mean-square error of test of 0.3359 and 2.2239, respectively. The result was better than that of the rice spectra and was close to that of the husked rice spectra. When the moisture content was integrated into the regression model of amylase activity, a better result was obtained. Thus, the proposed method can detect amylase activity and moisture content in rice accurately.

This study presents a facile strategy for the formation of highly substituted butterfly 1,4-adducts/9,10-adducts via the Diels–Alder reaction of benzyne intermediates. The method achieves very good to excellent yields of the respective anthracene derivatives under mild conditions. This practical protocol is compatible with a variety of sensitive functional groups and provides access to difunctionalized bridge 1,4-adducts/9,10-adducts.

Lysinibacillus sphaericus C3-41 carries a large low-copy-number plasmid pBsph, which encodes binary toxin proteins. Our previous study found that the transcriptional activator TubX plays an important role in the newly identified type Ⅲ TubRZC replication/partition system in pBsph, and that a vector consisting of tubRZC and tubX is not as stable as pBsph, indicating the presence of other maintenance module(s). In this study, we identified that orf9 and orf10 are necessary for the stability of pBsph by a series of deletion and complementation experiments. Bioinformatics analysis showed that ORF9 contains a PIN domain of VapBC toxin-antitoxin (TA) system, whereas ORF10 share no significant sequence similarity to any of the characterized antitoxins in the database. Further studies revealed that orf9 and orf10 are transcribed as an operon. The overexpression of ORF9 repressed the growth of both Escherichia coli and L. sphaericus, which can be alleviated by overexpression of ORF10. The deletion of orf10 individually or orf9-10 together resulted a decrease on plasmid stability which was restored by the complementation of corresponding gene(s), suggesting that ORF10 plays an important role in plasmid stability. In addition, it was found the plasmid stability is related with the transcription level of tubRZ, and overexpression of TubRZ could neutralize the negative effect on plasmid stability caused by the deletion of orf9-orf10. Moreover, the recombinant vector containing tubRZC, tubX and orf9-10 was more stable than the ones containing only tubRZC and either tubX or orf9-10. The data indicate that the plasmid maintenance system on pBsph includes orf9-orf10 TA system.

Poly (2-aminothiophenol) (PATP)/MnO2 nanocables have been fabricated through in situ growth of MnO2 nanoflakes on surfaces of PATP nanofibers thanks to the redox activity between PATP and KMnO4. The coating amount of MnO2 shells can be well-controlled by determining the KMnO4 precursor concentration. When used as adsorbents, the PATP/MnO2 nanocables showed excellent adsorption capacity towards heavy metal ions owing to the integrated physical and chemical adsorption behaviors resulted from MnO2 inorganic oxide and PATP polymer. Effect of Pb(II) ions concentration, solution pH, ionic strength and coexisting ions on the on Pb(II) ions adsorption have been investigated. In addition, the adsorption data of PATP/MnO2 adsorbent toward Pb(II) ion fits the Freundlich isotherm. The developed PATP/MnO2 adsorbents synthesized by a facile and economic route are believed to show high potential in environmental remediation for heavy metal removal.

DegS and DegU make up a two component system belonging to a class of signal transduction systems that play important roles in a broad range of bacterial responses to the environment. However, little study has been done to explore the physiological functions of DegS-DegU in mosquitocidal Lysinibacillus sphaericus . In this study, it was found that deletion of degU or degS-degU inhibited the swarming motility , biofilm formation, sporulation and binary toxin production through regulating the related genes, and phosphorylation was necessary for the functions of DegU. Based on the findings, a regulation network mediated by DegU was delineated. Both DegU-pi and Spo0A-pi positively regulates genes which are linked with the transition from stage Ⅱ to the end of the sporulation process and also influences the production of binary toxins via regulation on sigE. Both DegU-pi and Spo0A-pi negatively regulate abrB/sinR and influence the biofilm formation. DegU-pi can positively regulate the motility via the regulation on sigD. Whether the regulations are directly or indirectly need to be explored. Moreover, Spo0A-pi may indirectly regulate the swarming motility through negatively regulating DegU. It was concluded that DegU is a global transcriptional regulator on cell swarming motility, biofilm formation, sporulation and virulence in L. sphaericus.

An efficient approach to N, N′-unsymmetrically substituted ureas 9 has been developed through the ammonolysis process of N-Boc protected anilines 7 with amines prompted by 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD). Moreover, a convenient protocol for the synthesis of the symmetric N, N'-substituted ureas 12 by one-pot diammonolysis process of Boc2O with amines catalyzed by DABCO has also been achieved. With broad substrate scope and mild conditions, these two methods demonstrate practical preparation of both unsymmetrical and symmetrical ureas.

Two new citrinin derivatives, pencitrin (1) and pencitrinol (2), and a known compound citrinin (3), together with its two known dimers, penicitrinone A (4), penicitrinone E (5), were isolated from an endophytic fungus P. citrinum 46 derived from Salicornia herbacea Torr. by adding CuCl2 into fermentation medium. The structures of these compounds were elucidated by detailed spectroscopic analysis, and the absolute configurations of 1, 4, and 5 were determined by comparison of quantum chemical time-dependent density functional theory (TDDFT) calculated and electronic circular dichroism (ECD) spectra. Compound 1 exhibited potent cytotoxic activities towards A549 human lung cancer cells and HepG2 human liver cancer cells with IC50 values of 23.73 ± 3.61 and 35.73 ± 2.15 μM, respectively, whereas compound 5 showed moderate cytotoxic activities towards A549 and HepG2 cancer cells with IC50 values of 40.47 ± 4.52 and 53.57 ± 3.24 μM, respectively. The results from the current research highlighted the effectiveness and usefulness of the pipeline to discover novel bioactive fungal secondary metabolites by modification of the culture media.

This paper proposes a novel multiple-stress-based predictive model (MSBPM) to rapidly assess the lifetime of light-emitting diodes (LEDs). The MSBPM addresses the lifetime estimation of LEDs with respect to temperature, humidity, and current; these three stresses are rarely considered simultaneously in the assessment of reliability. Using several degradation data sets from accelerated life tests (ALTs) without using extrapolation method, a designed adaptive genetic algorithm is employed to identify five unknown parameters of the MSBPM. A simulation of the proposed MSBPM is presented as validation. By applying the degradation data from the ALTs under high stresses, an MSBPM for the LEDs is established. Under the nominal conditions of 25 °C/22.5% RH and a current of 0.35 A, the lifetime of the LED is estimated using the established MSBPM. The effectiveness of the proposed MSBPM is further verified through the estimated results.

Biomimetic mineralized hybrid scaffolds are widely used as natural bone substitute materials in tissue engineering by mimicking vital characters of extracellular matrix (ECM). However, the fabrication of hybrid scaffolds with suitable mechanical properties and good biocompatibility remains a challenge. To solve the problems mentioned above, biomimetic calcium phosphate mineralized organic-inorganic hybrid scaffold composed of nano hydroxyapatite (nHAP), Chitosan (CS), Chondroitin sulfate (CSA) and hyaluronic acid (HA) with hierarchical micro/nano structures was successfully developed. In this process, an efficient and easy-to-accomplish method combining in situ biomimetic synthesis with freeze-drying technology was applied. The chemical structure of the scaffolds was confirmed by Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). Surface morphology of scaffolds was characterized by Scanning electron microscopy (SEM). The nHAP/CS/CSA/HA hybrid scaffolds with a well-distributed pore size showed suitable mechanical strength which is not only due to the addition of the nHAP but also the interaction between the positively charged CS and the negatively charged CSA and HA. Simultaneously, the biocompatibility was evaluated by the MTT cytotoxicity assay, alkaline phosphatase (ALP) activity, Hoechst 33258 fluorescence staining. All those results proved that the scaffolds possess good biocompatibility and the components added have enhanced the proliferation and differentiation of osteoblast. Thus, it can be anticipated that the in situ biomimetic mineralized nHAP/CS/CAS/HA hybrid scaffolds will be promising candidates for bone tissue engineering.

Recent research has established growing research interest in subject of conducting polymer (CP)-based hybrids due to their novel properties and potential applications in diverse fields. The incorporation of CPs with other materials can produce new hybrids showing distinct properties that are not observed in the individual components. Among numerous CP-based hybrids, CP and noble metal nanoparticle (NMNP) hybrids have attracted the most intensive attention in the past few years. The numerous functional groups and tunable chemical structures through redox in the main chains of CPs, make them as ideal supporters for NMNPs. The compact interactions and synergistic effects between CPs and NMNPs contribute to the increased performances in diverse applications. The purpose of this review focuses on state-of-the-art synthetic strategies, mechanisms and applications involved in CP-NMNP hybrids. Herein, CPs used are polyaniline (PANI), polypyrrole (PPY), polythiophene (PTH) and their derivatives; while NMNPs mainly refer to Au, Ag, Pt and Pd nanoparticles. Specifically, the topics include: 1) strategies and mechanisms involved in the synthesis of CP-NMNP hybrids; 2) potential applications of CP-NMNP hybrids in fields of catalysis, sensor, surface-enhanced Raman scattering (SERS), device and others. Finally, prospects and challenges for making advanced CP-NMNP hybrids are discussed.

Polyacetylene glycosides, (6Z, 12E)-tetradecadiene-8,10-diyne-1-ol-3(R)-O-β-D-glucopyranoside (trivially named coreoside E) and (6Z, 12E)-tetradecadiene-8,10-diyne-1-ol-3(R)-O-β-L-arabinopyranosyl-(1 → 2)-β-D-glucopyranoside (trivially named coreoside F), were isolated from buds of Coreopsis tinctoria Nutt., together with one known compound, coreoside B. Their chemical structures were elucidated by extensive spectroscopic analysis and on the basis of their chemical reactivities. Coreoside E exhibited high levels of antimicrobial activity against Staphylococcus aureus and Bacillus anthracis with minimum inhibitory concentrations of 27 ± 0.27 and 18 ± 0.40 μM, respectively, whereas coreoside F and coreoside B showed weak antimicrobial activity against S. aureus and B. anthracis.

The fabrication of bone scaffolds with interconnected porous structure, adequate mechanical properties and excellent biocompatibility presents a great challenge. Herein, a hybrid nanostructured chitosan/chondroitin sulfate/hydroxyapatite (ChS/CSA/HAP) in situ composite scaffold was prepared by in situ fabrication and freeze-drying technique. The composition and morphology of scaffold were characterized by Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM). It proved that the low crystallinity of HAP crystals were uniformly distributed in ChS/CSA organic matrix and the nanostructured hybrid scaffold exhibited good mechanical property. The biocompatibility and in vitro bioactivity were detected by MTT-assay, maturation (alkaline phosphatase (ALP) activity), Hoechst 33258 and PI fluorescence staining. In vitro tests indicated that the hybrid scaffold not only promoted the adhesion and proliferation of osteoblasts, but also improved the growth of the osteoblasts. Therefore, it is promising for bone repair application in bone tissue engineering.

A convenient method was developed for the cyclopropanation of aryl acetates and aryl acetonitrile using vinyl diphenyl sulfonium triflate salt. The newly developed conditions are simple, mild, and compatible with a wide range of functional groups, without the need to apply an inert atmosphere, or alkali bases.

This review explores state-of-the-art and new perspectives description of scaffold-based strategies utilized in in-suit bone tissue engineering. The bone defects caused by severe trauma and tumor resection can't be healed by themselves. It needs to apply exogenous bone induction materials to recover effectively. In recent years, with the rapid development of bone repair materials and tissue engineering, in-situ bone tissue engineering provides a new choice for the treatment of bone defects. The key point is to prepare cell-free scaffolds instead of grafts and implant them in the defect area to achieve bone healing. Therefore, this paper describes in detail the preparation needs, in-situ preparation methods, functional bone repair scaffold and the application of functional scaffold composite in in-situ tissue engineering.

This research aims to prepare the biphasic-induced magnetic composite microcapsules (BIMCM) as a promising environmental stimuli-responsive delivery vehicle to dispose the problem of drug burst effect. The paper presented a novel automated in situ click technology of magnetic chitosan/nano hydroxyapatite (CS/nHA) microcapsules. Fe3O4 magnetic nanoparticles (MNP) and nHA were simultaneously in situ crystallized by one-step process. Icariin (ICA), a plant-derived flavonol glycoside, was combined to study drug release properties of BIMCM. BIMCM were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and Thermal gravimetric analysis/Differential Scanning Calorimetry(TGA/DSC) in order to reveal their component and surface morphology as well as the role of the in situ generated Fe3O4 MNP and nHA. The magnetic test showed the BIMCM were super-paramagnetic. Both in situ generated Fe3O4 MNP and nHA serve as stable inorganic crosslinkers in BIMCM to form many intermolecular crosslinkages for the movability of the CS chains. This makes ICA loaded microcapsules take on a sustained release behavior and results in the self-adjusting of surface morphology, decreasing of swelling and degradation rates. In addition, in vitro tests were systematically carried out to examine the biocompatibility of the microcapsules by MTT test, Wright-Giemsa dying assay and AO/EB fluorescent staining method. These results demonstrated that successful introduction of the in situ click Fe3O4 MNP provided an alternative strategy because of magnetic sensitivity and sustained release. As such, the novel ICA loaded biphasic-induced magnetic CS/nHA/MNP microcapsules are expected to find potential applications in drug delivery system for bone repair.

Excessive N fertilization is a problem in the intensive cropping systems on the North China Plain. Proper N management is essential to maximize N efficiency and sustain agricultural production while minimizing negative impacts on the environment. The aim of the present study was to investigate N dynamics, maize yields and soil fertility in response to short term compost application and straw return vs. inorganic fertilization. A field experiment (2012–2014) was conducted for three years on a calcareous soil in Quzhou county, Heibei province, north China. There were four treatments: unfertilized control (T1), inorganic fertilizer (100% NPK, T2), compost (cattle wastes) + 70% NPK (T3), T3 + wheat straw (T4). No significant differences in biomass accumulation or N uptake among the fertilized treatments were observed across the maize growing season. Compost application for three years tended to increase grain yields particularly in the second and third years, and the average yield increase was approximately 7–15% over T2. Residual Nmin down the soil profile (1 m) in the compost treatments (T3 and T4) decreased by 50% deeper in the soil (60–100 cm depth) at the maize harvest in 2014. Compared to T2, the compost treatments significantly increased NUE and soil available P and K contents. Correlation analysis indicates that maize yield in 2014 was significantly correlated with soil available P and K and with soil organic carbon (SOC). Overall, straw return did not have a significant influence on any measured parameters in either soil or plant samples. Our results demonstrate that 30% replacement of N fertilizer by compost is an effective nutrient management strategy to maintain N uptake and yield of maize, reduce N loss and also increase soil fertility. A considerable increase in invertase activity in the compost treatments highlights that the critical importance of integrating the management of carbon and nitrogen for sustainable agricultural production in this region of highly intensive production.

Background Quantifying acute hypoxia is desirable yet challenging in radiation therapy. Here, we report a simulation study on the feasibility of mapping acute hypoxia, generated in a 2D simulation vasculature of a pancreas model, using in situ 15O washout images. The influence of varying tissue types and photon beam energies (i.e., 20, 25, 30 and 50 MeV) was investigated. Method and materials An ex vivo autoradiography 64Cu-ATSM image of a rat tumor was used as a surrogate for the microvessel density map. It was then input to a reaction diffusion model to simulate a steady state partial oxygen pressure (pO2) map. The resulting in situ 15O-PET image was generated using a high-energy photon beam and included both mobile and immobile 15O. An image of 15O washout was produced by subtracting the immobile decay portion from the overall decay curve in the in situ PET image, (i.e., fitting the sum of the two exponentials for mobile and immobile oxygen) using different decay constants. Finally, the pO2 map and in situ 15O washout images were thresholded and compared. Results The reaction diffusion model showed a heterogeneous distribution of pO2 with mean values of 27.4 and 16.8 mmHg, depending on microvessel permeability, tumor vasculature structure, and architecture. A 62% threshold of the mean intensity in the in situ 15O washout image was found to agree reasonably well with the original hypoxia map using 5 mmHg as a cutoff value. These parameters yielded two sets of images with hypoxia fractions of 0.146 and 0.152, respectively. Conclusions This simulation study demonstrates the feasibility of mapping acute hypoxia using tissue in situ activation with high-energy photons. With recent advances in in-room or in-beam PET and more work being performed on thresholding the in situ 15O washout, mapping acute hypoxia in real time may become a reality.

Background aims Autologous transplantation of granulocyte colony-stimulating factor–mobilized peripheral blood mononuclear cells (M-PBMNCs) has been shown to be effective in treating critical limb ischemia (CLI); however, the studies of the possible prognosis predictors after autologous M-PBMNC transplantation are inadequate. The objective of the study was to assess the possible factors affecting the results of M-PBMNC transplantation for CLI. Methods We reviewed the clinical profiles of 87 patients with CLI who were treated with M-PBMNC implantation in the Blood Diseases Hospital, Chinese Academy of Medical Sciences, between December 2002 and December 2011, and we followed these patients. The patients were divided into a good prognosis group and a poor prognosis group on the basis of whether amputation was performed. The significant differences of clinical variables between two groups were analyzed by means of the Mann-Whitney test and χ 2 test, and logistic regression analysis was used to study the variables representing the possible prognostic factors for amputation. Results Of the 87 patients, three patients died and one patient was lost during the follow-up period. We analyzed 83 patients. The diseases included CLI complicated by diabetes mellitus gangrene (35 cases, 42.2%), arteriosclerosis obliterans (31 cases, 37.3%) and thromboangiitis (17 cases, 20.5%). The mean age was 62 years (range, 30–87). The median follow-up time for the surviving patients was 5 years. The 5-year amputation-free rate was 72.2%, and no adverse effects related to M-PBMNC transplantation were observed. Conclusions The significant prognostic factors associated with poor angiogenesis were fibrinogen >4 g/L and fasting blood glucose >6 mmol/L.

A formal [3+2] annulation reaction of 1,4-dithiane-2,5-diol and N -substituted imides through one-pot metal-free strategy has been developed. This method could furnish 2,3-thienoimides in good to high yields.

Et3N-catalyzed [3+2] cycloaddition of 1,4-dithiane-2,5-diol with ynal has been developed. This strategy provides a rapid way to synthesize 3-aldehyde-2-substituted thiophene in one portion and the desired products could be obtained in high yields, which contain various functional groups.

The efficient cross-coupling of bromo(iso)quinoline to 1,6-diynes with the Pd-catalyzed system was established. Using unactivated simple diynes with bromo(iso)quinoline in the presence of palladium catalytic system afforded different kinds of rare 7,11-diphenyl-9,10-dihydro-8H-pyrrolo[3,4-j]phenanthridine derivatives through regioselective C–H functionalization in one step. Different diynes (a–p) and different bromo(iso)quinolines were shown to be very active in the reaction. Thus, the generality of this process makes the reaction highly valuable in view of the synthetic and medicinal importance of these pyrrolo[3,4-j]phenanthridine derivatives.

An efficient method via sequential domino allylation/olefination of C–C triple bonds for the syntheses of five-membered heterocycles was developed by treatment 1,6-enynes with alkenes in the presence of a palladium catalyst. The configurations of the 1,3-dienes of the five-membered heterocycles are stereocontrolled.

An efficient and general route for the synthesis of functionalized hexahydroindole and hexahydrobenzofuran derivatives has been developed via the palladium-catalyzed domino coupling/cyclization reaction of 1,6-enynes and aryl halides. The results indicated that the electronic properties of the aryl halides strongly affect the reaction yields.

Antidepressants have been widely used to treat neuropathic pain for many years. However, the mechanisms of their analgesic actions are little known and remain controvertible. Recent studies indicate that cytokines in central nervous system (CNS) play a critical role in the pathological states of pain. The present study was designed to explore the effects and most appropriate dosage of mirtazapine in treating neuropathic pain and its possible neuroimmune mechanisms. L5 spinal nerve transection was done to produce hyperalgesia in rats. Mirtazapine (10, 20 and 30 mg/kg, respectively) was orally administered daily for 14 days, beginning from the 5th day after nerve transection. Mechanical and thermal hyperalgesia was measured using Von-Frey filament and Hargreaves tests before and after the surgery. Rats were then sacrificed on days 3, 7, 14, 21 post-administration. The inflammatory cytokines production such as TNFalpha, IL-1beta, IL-10 and nuclear factor kappa B (NF-kappaB) activity in brain was quantified using enzyme-linked immunosorbent assay (ELISA) and electrophoretic mobility shift assay (EMSA). We found that mirtazapine (20 and 30 mg/kg) can markedly attenuate mechanical and thermal hyperalgesia produced by nerve transection, most significantly on the 14th day. The elevated TNFalpha, IL-1beta and NF-kappaB in brain were accordingly reduced, while the expression of increased IL-10 were even stimulated after repeated mirtazapine administration. Our data could conclude that mirtazapine suppressed neuropathic pain partially through inhibiting cerebral proinflammatory cytokines production and NF-kappaB activation in CNS.