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In this paper, a series of novel Sr3-xGa2Ge4O14:xDy3+ (x = 0 - 0. 40) (mole fraction) and Sr2.68Ga2Ge4O14 :0. 16Dy3+, 0. 16M+ (M = Li, Na, K) phosphors were prepared by high-temperature solid-phase method. EDS analysis confirms the presence of Sr, Ga, Ge, O and Dy elements in the phosphors. The series Sr3-xGa2Ge4O14 :xDy3+ produce strong yellow light emission with 568 nm as the dominant wavelength under 350 nm optical excitation, corresponding to the 4F9/2→6H13/2 transition. The emission spectra of the phosphor show that the emission intensity varies with the increase of Dy3+ concentration and reaches its maximum at x = 0. 16. The co-doping of alkali metal M(M = Li, Na, K) as a charge compensation ion, among which Li+ has the most obvious effect on increasing the emission intensity of Dy3+, led to the increase of the emission intensity of the phosphor to twice that of the phosphor in the absence of the charge compensation ion. In addition, the fluorescence lifetime of the phosphor decrease continuously with the increase of Dy3+ doping concentration. Finally, the CIE chromaticity coordinates and thermal stability of the phosphor Sr2.68Ga2Ge4O14 :0.16Dy3+, 0.16Li+ are explored, and its CIE chromaticity coordinates are (0. 371 9, 0.404 6), which are located in the yellow region, and its luminescence intensity at 453 K is about 95. 5% of its room temperature luminescence intensity. Therefore, Dy3+, Li+ co-doped Sr3-xGa2Ge4O14 phosphor is a potential candidate material for display devices and white light LED devices. [ABSTRACT FROM AUTHOR]

Graphene oxide (GO) surface contains a large amount of oxygen containing groups, which is of good hydrophilidty. It is a new type of Nano carbon material that affects the shape and aggregation state of cement hydration products. In this paper, multilayer GO and water were mixed to form GO dispersions by ultrasonic dispersion. The autogenous shrinkage of fresh cement paste with different GO content was tested and IS pore structure was characterized by nitrogen adsorption method. The results showed that the incorporation of GO increased the free water in the gel pores and accelerated the hydration rate of the cement. The autogenous shank age increased as the GO content increased. It was deduced from the hysteresis effect that GO made the pores inside the cement paste develop into a sit. The pore distribution was analyzed by the BJH method of Kelvin equal- ion to explore the regulation mochas of GO on autogenous shrinkage. It was found that GO could reline the maternal pore diameter. The large capillary pores inside the cement slurry were transformed toward the small capillary pores, which led to an increase in capillary pore pressure, thereby increasing the autogenous shrinkage of the cement-based composite material. [ABSTRACT FROM AUTHOR]

Due to its unique structure and excellent properties, (β-cyclodextrin, as a green environmental material, is widely used in the fields ff the drug, medicine and environment and so on, and plays an increasingly important role. The excellent properties of (β-cyclodextrin and its derivatives were introduced. Several modification principles and methods of (β-cyclodextrin were briefly introduced. The preparation methods of (β-cyclodextrin nanoparticles and the results of their application researches in the fields of medicine and environment in recent years were mainly reviewed. Finally, the further works on the anti-tumor effect of modified β-cyclodextrin microparticles were suggested, and the modified methods to expand its application were forecasted. [ABSTRACT FROM AUTHOR]

To enhance the vibration control bandwidth of active-passive hybrid piezoelectric network ( APPN), a kind of piezoelectric hybrid constrained layer damping ( PHCLD ), which combined the advantages of the APPN and passive constrained layer damping, was presented to control the vibrations of cantilever beams. Complex shear modulus was used to characterize the dynamic behavior of viscoelastic material, and Hamilton's principle with Raleigh-Ritz method was employed to establish the dynamic model of the cantilever beams with PHCLD treatments. On this basis, the velocity feedback control strategy was used to design the active controller, and numerical simulations were performed to analyze the open-loop and closed-loop characteristics of the beam/PHCLD system. Analysis results indicate that the PHCLD has better vibration control performance and wider vibration control bandwidth as compared with the APPN. Furthermore, this PHCLD treatment could be easily extended to control the vibrations of other kinds of structures. [ABSTRACT FROM AUTHOR]

In this paper, a series of novel Sr3-xGa2Ge4O14:xDy3+ (x = 0 - 0. 40) (mole fraction) and Sr2.68Ga2Ge4O14 :0. 16Dy3+, 0. 16M+ (M = Li, Na, K) phosphors were prepared by high-temperature solid-phase method. EDS analysis confirms the presence of Sr, Ga, Ge, O and Dy elements in the phosphors. The series Sr3-xGa2Ge4O14 :xDy3+ produce strong yellow light emission with 568 nm as the dominant wavelength under 350 nm optical excitation, corresponding to the 4F9/2→6H13/2 transition. The emission spectra of the phosphor show that the emission intensity varies with the increase of Dy3+ concentration and reaches its maximum at x = 0. 16. The co-doping of alkali metal M(M = Li, Na, K) as a charge compensation ion, among which Li+ has the most obvious effect on increasing the emission intensity of Dy3+, led to the increase of the emission intensity of the phosphor to twice that of the phosphor in the absence of the charge compensation ion. In addition, the fluorescence lifetime of the phosphor decrease continuously with the increase of Dy3+ doping concentration. Finally, the CIE chromaticity coordinates and thermal stability of the phosphor Sr2.68Ga2Ge4O14 :0.16Dy3+, 0.16Li+ are explored, and its CIE chromaticity coordinates are (0. 371 9, 0.404 6), which are located in the yellow region, and its luminescence intensity at 453 K is about 95. 5% of its room temperature luminescence intensity. Therefore, Dy3+, Li+ co-doped Sr3-xGa2Ge4O14 phosphor is a potential candidate material for display devices and white light LED devices. [ABSTRACT FROM AUTHOR]

Compared with conventional cardiopulmonary resuscitation (CCPR), extracorporeal cardiopulmonary resuscitation (ECPR) can improve the survival rate of patients with cardiac arrest, and reduce the risk of reperfusion injury. However, it is still difficult to avoid the risk of secondary brain damage. Low temperature management has good neuroprotective potential for ECPR patients, which minimizes brain damage. However, unlike CCPR, ECPR has no clear prognostic indicator. The relationship between ECPR combined with hypothermia management-related treatment measure and neurological prognosis is not clear. This article reviews the effect of ECPR combined with different therapeutic hypothermia on brain protection and provides a reference for the prevention and treatment of neurological injury in patients with ECPR.

Objective To investigate the effect of resolvin D1 (RvD1) on the injury of PC12 cells induced by activated BV-2 microglia and the related mechanisms. Methods BV-2 cells were divided into control group, lipopolysaccharide (LPS)-treated group, RvD1-treated group and RvD1 combined with LPS (RvD1-LPS)-treated group. After BV-2 cells were incubated with the corresponding substances for 12 and 24 hours, the levels of interleukin-1β (IL-1β), IL-6, tumor necrosis factor-α (TNF-α) in the supernatants were determined by ELISA. The culture supernatants of BV-2 cells were collected at 24 hours and added into PC12 cells for another 24-hour culture. Thereafter, the survival rate of PC12 cells was tested by MTT assay. The expression of NF-κB p65 protein in BV-2 cells was deteced by Western blotting. Results Compared with the control group, the survival rate of PC12 cells in the LPS group significantly decreased; the levels of IL-1β, IL-6 and TNF-α in the supernatant of BV-2 cells and the nuclear translocation of NF-κB p65 significantly increased in the LPS group. Compared with the LPS group, the survival rate of PC12 cells in RvD1-LPS group was significantly elevated; the levels of IL-1, IL-6, TNF-α and the nuclear translocation of NF-κB p65 were significantly reduced in RvD1-LPS group. Conclusion RvD1 can inhibit the injury of PC12 cells induced by activated BV-2 microglia through inhibiting the nuclear translocation of NF-κB p65 and inflammatory factor levels in BV-2 cells.

Shikimic acid (SA), as a hydroaromatic intermediate in the common pathway of aromatic amino acid biosynthesis, is the starting material for the synthesis of neuraminidase inhibitors and other useful compounds. The fermentative production of SA by metabolically engineered microorganisms is an excellent alternative to the extraction from fruits of the Illicium plant. In this study, Escherichia coli was metabolically engineered by rational design and genetic manipulation for fermentative production of SA. Firstly, blocking the aromatic amino acid pathway after the production of SA was carried out by deletion of aroL and aroK genes encoding SA kinase. Secondly, the ptsG gene encoding protein EIICBglc were removed in the aroL/aroK mutant strain to make the phosphotransferase system (PTS) system default. In the resulting strain, the phosphoenolpyruvate-dependent PTS pathway, a main pathway for glucose transport, were replaced by ATP-dependent GalP (galactose permease). Thus, more PEP flux was used to produce SA as a critical precursor of SA. Furthermore, ydiB gene (encoding quinic acid/SA dehydrogenase) was deleted to prevent SA precursors of 3-dehyroquinic acid into the byproduct of quinic acid. Thus, the engineered strain with four genes deletion was constructed and 576 mg/L SA was produced in the shake flask fermentation. Results show that SA produciton was increased 90 times compared to the parent strain E. coli CICIM B0013.

Background: Abnormal proliferation and metastasis is the basic characteristic of malignant tumors. The aim of this work is to explore the effects of zoledronic acid on cell proliferation and invasion in lung cancer cell line 95D., Methods: The effect of zoledrnic acid (ZOL) on proliferation of lung cancer cell line 95D was detected by MTT. The expression of proliferation and invasion-relation genes and proteins were detected by Western blot, RT-PCR and immunofluorescence. Changes of invasion of lung cancer cell numbers were measured by polycarbonates coated with Matrigel., Results: ZOL could inhibit the proliferation of lung cancer cell line 95D in vitro in a time-dependant and a dose-dependant manner. With time extending after ZOL treated, the mRNA expresion of VEGF, MMP9, MMP2 and protein expression of VEGF, MMP9, ERK1/ERK2 were decreased. The results of Tanswell invasion showed the numbers of invasive cells were significantly reduced in 95D cells treated with ZOL 4 d and 6 d later., Conclusions: ZOL could inhibit cell proliferation and invasion of lung cancer cell line 95D.