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Abstract Polyimide (PI) dielectric nanocomposites containing functional nanofillers based on layered structure (single-layer: BT@[Al.sub.2][O.sub.3]@PI, double-layer: PI/BT@[Al.sub.2][O.sub.3]@PI, three-layer: PI/BT@[Al.sub.2][O.sub.3]@PI/PI) were designed and prepared by using PI as matrix, barium titanate (BT)@alumina [...]

A 1,2:3,4:9,10:9,19-tetraseco-cycloartane triterpene spiroketal lactone, pseudoamaolide P (1), two new labdane-type diterpenoids, pseudoamains A and B (2-3), and four known cembrane-type diterpenoids (4–7) were isolated from the seeds of Pseudolarix amabilis. The structures of these compounds were elucidated by spectroscopic analyses, including HRESIMS, 1D-, and 2D-NMR. The anti-inflammatory activities of the compounds were evaluated by suppressing the transcription of the NF-κB-dependent reporter gene in LPS-induced 293 T/NF-κB-luc cells. All compounds do not show potent activity. [ABSTRACT FROM AUTHOR]

The status and sources of OMPs pollution in urban surface runoff and the effects mechanisms influencing factors and migration models of OMPs removed by bio retention facilities are reviewed. The re-sults show that OMPs in urban runoff mainly come from human production and life and their removal in bio retention facilities mainly depends on soil adsorption plant uptake and biodegradation and the removal effect of OMPs can be improved by optimizing filler design-laying plants or adjusting microbial communities. Multi-media migration models have good applicability in bio retention facilities but how to quantify the pollution flux between various environmental phases and develop a migration model with spatial heterogeneity is still a key research direction in the future. [ABSTRACT FROM AUTHOR]

In order to explore effective strategies to fabricate main‐chain polybenzoxazine (PBZ) thermosetting resin for structural material applications, here, five PBZ with different molecular structures, that is, poly(Co‐ddm), poly(Co‐BPA‐ddm‐Co)main, poly(Ph‐BPA‐ddm‐Co)main, poly(Ph‐BPA‐ddm‐Ph)main and poly(Ph‐ddm) were designed, synthesized and compared by introducing unsaturated fatty chains through the Mannich reaction with cardanol. The structure and properties of five PBZ with different structure were systematically investigated by using Fourier transform infrared (FTIR), NMR, water absorption and mechanical tests. FTIR and NMR tests indicated that five PBZ with different molecular structures were successfully synthesized. The mechanical tests indicated that the impact strength of the double‐capped cardanol‐based main‐chain PBZ was 243% higher than that of the traditional PBZ. The water absorption of main‐chain PBZ was higher than that of diamine PBZ, and the water absorption of poly(Ph‐BPA‐ddm‐Co)main was the lowest in the main‐chain PBZ. Based on the experimental results, five PBZ amorphous cells with different structures were successfully established. It indicated that the main chain PBZ showed better thermomechanical properties than the traditional diamine PBZ due to high crosslinking conversion and hydrogen bond density. Moreover, the modulus and glass transition temperature of the main chain structure containing unsaturated fatty chains did not decrease significantly. [ABSTRACT FROM AUTHOR]

Through deeply analyzing on the principle,mode,character of DoS,and the DoS attack faced by SIP network,combining with the idea of Client Puzzle,DFA,long-distance linkage,host linkagethe,the character of SIP network,and the principle of SIP proxy server,the defence model of SIP proxy server for DoS attack was put forward,and the testbed to test the ability of this model to resist DoS attack was designed.The experiment result proves that this model can effectively resist the DoS attack for SIP proxy server with millisecond delay of signal transfer,and improves the usablity of SIP network.

Through analyzing the security of SIP,combining PKI technology,digital time authentication,digital certifi-cate and the characteristic of SIP network,the safe communicated model of SIP network based on improved SIP protocol was put forward.New call established protocol was constituted used the primary flow for reference,new register protocol and roam register protocol were constituted,time synchronization protocol and negotiating key protocol was added for this model,and test the safe communicated model in real circumstance.The result of the experiment proved that this model improved the confidentiality,integrality,usability,non-repudiation and novelty of the SIP network with the millisecond delay which can be accepted.

In order to systematically investigate the dependence of the properties of nanocomposites on the shape of nanofillers, including spherical and fibrous, and the contents and its special arrangement, polyimide (PI) as matrix, nano-silicon carbide particles (SiCp) and whisker (SiCw) as fillers were applied to prepare PI nanocomposite films by in-situ polymerization. FTIR and XRD tests verified the successful polymerization of SiC/PI nanocomposites. FESEM observations showed that both SiCp and SiCw nanofillers were uniformly dispersed in the PI matrix during in-situ polymerization and contributed to the improvements of properties. Compared with pure PI film, addition of SiC nanofillers enhanced obviously the heat resistance and the thermal stabilities of PI nanocomposites, as verified by TGA. Tensile tests indicated that the mechanical properties of PI nanocomposites enhanced with increasing SiC nanofillers. Moreover, SiCw was more prominent than SiCp in the reinforcement of PI nanocomposites. Due to the influences of dielectric properties by the changes of the spatial arrangement and the local distribution of electric field of the nanofillers in PI matrix, the dielectric constant of 3wt.%SiCp/PI and 3wt.%SiCw/PI nanocomposites reached 4.3 and 5.6, respectively. Compared with pure PI film, the dielectric constants of SiCp/PI and SiCw/PI nanocomposites were enhanced by 26% and 64%, respectively. In comparison, PI nanocomposites containing SiCw possessed higher effective permittivity than those containing SiCp under the same nanofillers concentration. This work is expected to show great significance to understand the microscopic mechanism of PI dielectric nanocomposites for high energy-storage applications. [ABSTRACT FROM AUTHOR]

Two new diterpenoids, dauricumins A (1) and B (2), together with two known aromatic meroterpenoids (3 and 4), were isolated from the petroleum ether soluble fraction of the stems from Rhododendron dauricum through an HPLC-MS-SPE-NMR combination strategy. The absolute configurations of 1 and 2 were elucidated by ECD calculations and [Rh2 (OCOCF3)4]-induced CD spectrum analysis. In a membrane potential FLIPR assay, confluentin (4) showed an agonistic effect on GABAA receptor (EC50 = 20 µM). [ABSTRACT FROM AUTHOR]

In this study, a new and facile route has been developed to prepare graphene oxide (GO)/sodium benzoate (Sb) compounding nucleator (GO‐Sb) reinforced polyamide 6 (PA6) nanocomposites. The effects and mechanism of adding GO/Sb compounding nucleator on the morphology and properties of PA6 nanocomposites were systematically investigated. The experimental results showed that there are electrostatic interaction and π–π conjugation between GO and Sb, which make the GO‐Sb compounding nucleator homogenously dispersed in matrix and gain good interfacial adhesion. XRD and DSC analysis revealed that incorporation of Sb improved the formation of γ‐crystal. In addition, GO‐Sb significantly enhanced the crystallization temperature of PA6 nanocomposites due to "the heterogeneous nucleating effects". The tensile results showed that the tensile strength and elastic modulus of the nanocomposites can be obviously improved by incorporation of GO‐Sb compounding nucleator at low contents. The tensile strength and impact strength of the PA6‐GO‐Sb (100/0.05/0.25) nanocomposite were enhanced by 69.9% and 157.1%, respectively compared with pure PA6. Compared with pure PA6, the thermal conductivity of PA6‐GO‐Sb (100/0.05/0.25) nanocomposite increased by 258.8%. This simple and effective approach is believed to offer possibilities for broadening the graphene applications with the development of PA6‐graphene nanocomposites. [ABSTRACT FROM AUTHOR]

A facile strategy through incorporating barium titanate (BT)/multiwalled carbon nanotubes (MWCNTs) compounding dielectric nanofillers into polyvinylidene fluoride (PVDF) via melt‐processing was proposed. Benefiting from the strong interfacial interactions between BT and MWCNTs, as well as oxygen‐containing groups of BT/MWCNTs and fluorine atoms of PVDF, the sandwiched structure was constructed and thus tailoring the microstructure and enhancing the mechanical, thermal and dielectric properties of resultant nanocomposites. The effects of BT/MWCNTs multiscale dielectric nanofiller on the mechanical properties, heat resistance and dielectric properties of nanocomposites were investigated by infrared spectra, X‐ray diffraction (XRD), differential scanning calorimetry (DSC) analysis, field emission scanning electron microscope, tensile and dielectric tests. XRD and DSC analysis indicated that compared with neat PVDF, BT/PVDF and MWCNTs/PVDF nanocomposites, the BT/MWCNTs/PVDF nanocomposites showed higher crystallinity and thermal properties. The dielectric performance tests showed that the BT/MWCNTs/PVDF nanocomposites had better dielectric performance than those of BT/PVDF and MWCNTs/PVDF nanocomposites. At 100 Hz, the dielectric constant of BT/MWCNTs/PVDF nanocomposites reached 119, which was 14 times that of neat PVDF, and the dielectric loss was only 0.051. The BT/MWCNTs/PVDF nanocomposites showed the tensile strength of 57.7 MPa and the tensile modulus of 1226 MPa, respectively. This work provides a novel strategy for the fabrication of PVDF based dielectric nanocomposites, inspiring the research and development of PVDF in the energy‐related areas in the future. [ABSTRACT FROM AUTHOR]

Objective The study aimed to investigate the clinical efficacy and prognosis of different surgical methods for patients with osteosarcoma in limbs. Methods A retrospective analysis was made on clinical data of 68 patients with osteosarcoma underwent surgery in the Third Affiliated Hospital of Kunming Medical University and Kunming General Hospital of Chengdu Military Area Command of Chinese PLA from May 2010 to October 2012. According to the operation methods, patients were divided into: amputation group 20 cases, tumor bone shell inactivated bone replantation group 12 cases, massive bone allograft group 10 cases and tumor segmental resection and prosthetic replacement group 26 cases. The local recurrence rates, pulmonary metastatic rates and long-term survival rates of four groups were observed and analyzed statistically after operation. Results The local recurrence rate of amputation for osteosarcoma in limbs was lower than that of the tumor bone shell inactivated bone replantation, allografts bone joint transplantation and tumor section removal and artificial joint prosthetic replacement (P < 0.05), but there were no significant differences in the long-term survival rate and lung metastasis rate among four kinds of surgical methods (P>0.05). Conclusion Amputation is a disabling operation mode, so most patients are unable to accept. The surgical methods of tumor bone shell inactivated bone replantation, allografts bone joint transplantation and tumor section removal and artificial joint prosthetic replacement are conducive to the preservation of limb function, but the choice of surgical method should be based on the comprehensive analysis of individual patient to choose the operation scheme optimization. It is very important to reduce the operation complications and the incidence rate of operation and improve the surgical quality and the patient's postoperative quality of life. [ABSTRACT FROM AUTHOR]

Objective The aim of this study was to investigate the inhibition of different doses of fluvastatin in SPC-A-1 lung adenocarcinoma nude mice bone destruction. Methods 100 nude mice age range of 6 w to 8 w (20-22 g) were treated with zoledronic acid, saline and different doses of fluvastatin, and the inhibition of bone destruction was studied. The data were analyzed using SPSS19.0 statistical software. Results 75 nude mice were valid. In high dose group of fluvastatin, the number of aggravated nude mice bone destruction was the least, followed by zoledronic acid, moderate dose and low dose groups of fluvastatin. Conclusion Fluvastatin has inhibitory effect on bone destruction, and high dose group is better than those of zoledronic acid group, middle dose group, and low-dose fluvastatin group. [ABSTRACT FROM AUTHOR]

This work evaluated the interaction of perchlorate and trichloroethene (TCE), two common co-contaminants in groundwater, during bioreduction in serum bottles containing synthetic mineral salts media and microbial consortia. TCE at concentrations up to 0.3 mM did not significantly affect perchlorate reduction; however, perchlorate concentrations higher than 0.1 mM made the reduction of TCE significantly slower. Perchlorate primarily inhibited the reduction of vinyl chloride (VC, a daughter product of TCE) to ethene. Mechanistic analysis showed that the inhibition was mainly because perchlorate reduction is thermodynamically more favorable than reduction of TCE and its daughter products and not because of toxicity due to accumulation of dissolved oxygen produced during perchlorate reduction. As the initial perchlorate concentration increased from 0 to 600 mg/L in a set of serum bottles, the relative abundance of Rhodocyclaceae (a putatively perchlorate-reducing genus) increased from 6.3 to 80.6%, while the relative abundance of Dehalococcoides , the only known genus that is able to reduce TCE all the way to ethene, significantly decreased. Similarly, the relative abundance of Proteobacteria (a phylum to which most known perchlorate-reducing bacteria belong) increased from 22% to almost 80%. [ABSTRACT FROM AUTHOR]

By various chromatographic techniques and extensive spectroscopic methods, 17 abietane diterpenoids were isolated from the dichloromethane fraction of the 95% ethanol cold-soak extracts of the seeds of Pseudolarix amabilis, namely pseudoamaol A(1), 12α-hydroxyabietic acid(2), 12-methoxy-7,13-abietadien-18-oic acid(3), 13-hydroxy-8,11,13-podocarpatrien-18-oic acid(4), 15-hydroxy-7,13-abietadien-12-on-18-oic acid(5), 8(14)-podocarpen-13-on-18-oic acid(6), holophyllin K(7), metaglyptin B(8), 7α-hydroxydehydroabietinsaure-methylester(9), 7-oxodehydroabietic acid(10), 15-hydroxy-7-oxodehydroabietinsaure-methy-lester(11), 15-methoxydidehydroabietic acid(12), 7-oxo-15-hydroxy-dehydroabietic acid(13), 15-hydroxydehydroabietic acid(14), 8,11,13-abietatriene-15,18-diol(15), 8,11,13-abietatriene-15-hydroxy-18-succinic acid(16), and 7β-hydroxydehydroabie-tic acid(17). Compound 1 was a new compound. The isolated compounds were evaluated for their antitumor activities(HepG2, SH-SY5Y, K562), and compounds 8 and 17 showed potential cytotoxic activity against K562 cells, with IC&#95;(50) values of 26.77 and 37.35 μmol·L~(-1), respectively.

Two new diterpenoids, dauricumins A ( 1 ) and B ( 2 ), together with two known aromatic meroterpenoids ( 3 and 4 ), were isolated from the petroleum ether soluble fraction of the stems from Rhododendron dauricum through an HPLC-MS-SPE-NMR combination strategy. The absolute configurations of 1 and 2 were elucidated by ECD calculations and [Rh 2 (OCOCF 3 ) 4 ]-induced CD spectrum analysis. In a membrane potential FLIPR assay, confluentin ( 4 ) showed an agonistic effect on GABA A receptor (EC 50 = 20 µM).

Objective: To investigate the effects of local injection of insulin on the level of systemic blood glucose and granulation tissue formation of wound in patients with diabetic foot ulcer., Methods: Thirty-two patients with diabetic foot ulcer hospitalized in our wards from June 2009 to June 2010 were divided into insulin (I, n = 16) and control (C, n = 16) groups according to the random number table. For patients in I group, after debridement, one half of calculated dose of insulin diluted with equal amount of normal saline was injected diffusely into the base of the ulcer, and another half dose of insulin was subcutaneously injected into abdominal wall for 7 days, two times a day. For patients in C group, after debridement, primary insulin was subcutaneously injected into abdominal wall, 1 mL saline was subcutaneously injected into basal layer of ulcer for 7 days, two times a day. Before injection and 0.5, 1.0, 2.0, and 4.0 hours after injection (PIH), level of fasting blood glucose was determined. Before injection and on post injection day (PID) 3, 5, and 7, the growth of granulation tissue was assessed, and wound specimens were harvested for observation of CD34 expression and calculation of microvessel density (MVD). Data were processed with t test., Results: The levels of fasting blood glucose in both groups during observational time points ranged from 6.6 mmol/L to 12.8 mmol/L with a mean of (10.0 ± 2.2) mmol/L, and there was no statistical difference (with t values from 0.000 to 2.209, P values all above 0.05). Growth of granulation tissue in I group was more exuberant from PID 5, especially on PID 7 [(59.06 ± 1.58)%], which was significantly richer than that in C group [(23.61 ± 1.57)%, t = 17.420, P = 0.000]. New vessels were observed in I group from PID 3 as indicated by CD34 expression. There was no obvious difference in the number of MVD between I group and C group on PID 3 (t = 0.247, P > 0.05). The number of MVD per 200 times visual field in I group was respectively 8.34 ± 0.48, 11.22 ± 0.97 on PID 5 and 7, which was respectively higher than that in C group (4.42 ± 0.14, 5.44 ± 1.13, with t value respectively 16.568, 27.664, P values all below 0.01)., Conclusions: Local injection of insulin has a significant effect on systemic blood glucose in patients with diabetic foot ulcer, and it can promote the growth of granulation tissue and wound healing.