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Previous studies have shown that modulation of the receptor-mediated endocannabinoid system during ischemia injury can induce potent neuroprotective effects. However, little is known about whether cannabinoid-2 (CB2) receptor agonist would produce a protective effect on blood-spinal cord barrier (BSCB) during ischemia. Using an in vivo transient spinal cord ischemia model in rats, JWH-015 (1mg/kg, i.p.), a CB2 receptor selective agonist, or vehicles were injected 20 min before ischemia. The effects of JWH-015 on BSCB permeability, the major structural protein for the formation of caveolae, caveolin-1 (cav-1), tight junction (TJ) protein Occludin and zona occludens protein-1 (ZO-1) were examined at day 1, day 3 and day 7 of reperfusion after transient spinal cord ischemia in rats. Here we demonstrated that JWH-015 significantly down-regulated the expression of cav-1, up-regulated the expression of TJ proteins, and then decreased the permeability of BSCB compared with control group. In addition, using an in vitro BBB model, oxygen glucose deprivation (OGD) was applied to simulate spinal cord ischemia in vitro in Human brain microvascular endothelial cells (HBMECs). JWH-015 greatly increased the transepithelial electrical resistance (TEER) and changed the distribution of ZO-1 and Occludin. Moreover, JWH-015 induced the expression of p-PKB and p-FoxO1 protein and decreased the expression of cav-1, which were greatly reversed by ROS inhibitor or PI3K inhibitor. Taken together, all of these results suggested that JWH-015 might regulate the BSCB permeability and this effect could be related to paracellular and transcellular pathway. And pharmacological CB2R ligands offer a new strategy for BSCB protection during ischemic injury.

The study planned to determine proximate composition, antioxidant activity and chemical characterization in the fruit bodies of Auricularia auricula and pickled product. Two polysaccharide fractions (AAPF, AAPP) were purified from the fruiting body of A. auricula by ethanol precipitation, deproteination and macroporous resins and were subsequently lyophilized. The results showed that AAPF consisted of five monosaccharides, including glucose, rhamnose, arabinose, mannose and galactose with a molar ratio of 16.74:1.0:1.18:1.0:1.0; in contrast, AAPP was composed of four monosaccharides, namely arabinose, mannose, galactose and xylose with the molar ratio of 15.59:1.52:4.76:1.0. AAPF and AAPP were characterized by Fourier Transform Infrared spectroscopy (FTIR), which indicated peaks at approximately 3500cm(-1) and 522.28cm(-1) in the carbohydrate region and composed of β-glycoside linkages at the 1200-1000cm(-1) peaks. However, the antioxidant activity of AAPF demonstrated a significant result in scavenging free radicals except for DDPH. The in vitro test indicated that AAPF and AAPP have good antioxidant activity, demonstrating that A. auricula polysaccharide has immense potential as a functional food.

International audience; Propagation of elastic waves in acoustic metamaterials based on locally resonant viscoelastic phononic crystals is discussed. A variational formulation of the complex band structure for in-plane polarized waves is proposed and used to formulate a finite element model. Two different types of locally resonant band gaps are found for quasilongitudinal and quasishear waves, with distinct features in terms of complex bands and transmission bandwidth. The influence of viscosity on the complex band structure, transmission properties, and effective dynamic mass density of two-dimensional locally resonant metamaterials is further investigated. It is found that bands that were degenerate in the elastic case are separated when viscosity is introduced, and that sharp corners at high symmetry points become rounded. Transmission is generally worsened in passing bands, while it is enhanced inside locally resonant band gaps, contrary to what was observed previously for Bragg band gaps. All changes in the complex band structure and transmission spectra are solely due to the dispersive and dissipative effects of viscosity. It is also found that the negative mass density property may also disappear when viscosity is introduced. These results are relevant to practical applications of elastic and viscoelastic metamaterials.

The textile and clothing industry generates much pollution and consumes a large amount of resources. Improper uses and disposal of clothing products make the problems much more severe. Fast fashion products shorten the valid lifecycle and generate more waste than regular clothing products. Considering the features of fashion products, a system of a rent-based closed-loop supply chain is developed to improve the sustainability of fashion products. The supply chain processes (fashion design and manufacturing, laundry, logistics and disposal), the operations management issues (inventory management, closed-loop logistics, human-clothing matching, booking system and the rental pricing) and the sustainability promotion aspects (customization, responsive system, culture and policy aspects) are investigated by devising sustainable strategies. The rationalities of the developed system and strategies are reviewed and elucidated in detail. The results may contribute to building sustainable closed-loop fashion supply chains, the related information systems and operational and managerial mechanisms.

To investigate the clinical characteristics and prognostic factors of leptomeningeal metastases (LM) from solid tumors and to develop better treatment strategies.The clinical characteristics and follow-up results of 77 cases of leptomeningeal metastases (LM) from solid tumors diagnosed and treated in our hospital from 2002 to 2011 were retrospectively analyzed. Clinical characteristics, treatment methods and overall survival were analyzed using Kaplan-Meier method and Cox regression model.The median survival time for all the patients was 88 days. KPS score, control of the primary tumor and systemic treatment were correlated with survival time for the patients (P0.05 for all). The median survival time of systemic treatment was 150 d and those without systemic treatment (chemotherapy and/or targeted therapy) after LM was 60 d (P = 0.001). Systemic therapy combined with local treatment (radiotherapy to the meninges or intrathecal chemotherapy) further improved the survival time of patients. Multivariate analysis showed that KPS and short-term therapeutic response for the LM were independent prognostic factors (P0.05 for both).KPS and short-term therapeutic response are independent prognostic factores for leptomeningeal metastases from solid tumors. Systemic chemotherapy or targeted therapy can prolong the survival time. Systemic treatment (chemotherapy and/or targeted therapy) combined with radiation therapy or intrathecal injection may further improve the clinical outcomes.

Two polyimides, PI(C1-BA) and PI(C1-6FDA), based on an aromatic di- amine compound and two aromatic dianhydrides (biphenyltetracarboxylic dianhydride (BA) and 4,49-(hexafluoroisopropylidene)diphthalic anhydride (6FDA)) were newly syn- thesized. They were characterized by viscosity, Fourier transform infrared measure- ments, and X-ray analyses. X-ray results revealed that the crystallinity of PI(C1-BA) was lower than that of PI(C1-6FDA). The synthesized polyimides could be formed into stable and homogeneous thin films on an ITO (indium tin oxide) electrode, functioning as good hole-transport materials for organic electroluminescent (EL) devices. The double-layered EL devices, consisting of the hole-transport layer of these polyimides and an emitting layer of tris(8-quinolinolato)aluminum complex, exhibited a peak emission wavelength in the bright green at 524 -527 nm. Moreover, a maximum luminance of 355 cd/m 2 was achieved at a voltage of 13 V, with a current density of 600 mA/cm 2 for the EL device using PI(C1-BA) as a hole-transport layer. The phenomenon of an extended luminance of these EL devices was also found when the voltage was

A novel zinc complex, Zn(NDP)2 (NDP = 2-naphthyl-7-dimethylamino-1,3-propanedione), was synthesized and applied to an organic electroluminescent (EL) device as an emitting material and an electron-transporting material. The double-layered EL device has been fabricated by using triphenyldiamine derivative (TPD) as a hole-transporting layer and Zn(NDP)2 as an active emitting layer sandwiched between indium-tin oxide (ITO) and an alloy of Al/Li (99:1) electrodes. The deposited EL device was observed to emit a yellow-green light originating from Zn(NDP)2 with a maximum luminance of 1000 cd/m2 at 14 V and 200 mA/cm2.

N-Stearylacrylamide (SAAm), N-oleylacrylamide (OAAm), and N-laurylacrylamide (LAAm) were synthesized. They were characterized by 1H-NMR, 13C-NMR, FT-IR, melting point measurements, and elemental analysis. The copolymerizations of SAAm, OAAm, and LAAm with 2-[(3-(acrylamido)propyl)dimethylammonio]ethyl 2′-isopropyl phosphate were carried out, and a series of amphiphilic poly(acrylamide)s (1a,b, 2, and 3a,b) were obtained. These copolymers showed polyelectrolyte behavior in their viscous properties in polar solvents. X-ray diffraction analysis indicated that the copolymers 1a,b formed similar stacked bilayers with hydrophilic groups and hydrophobic parts. The polymorphic phase transition of these copolymers was also observed by DSC. In addition, the monolayers as well as LB films of these amphiphilic copolymers were prepared on the surface of water and their π–A isotherms were investigated at different temperatures. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 1293–1302, 1999

A novel europium complex, Eu(DTP)3(dipphen) (DTP = 1,3-di(2-thienyl)propane-1,3-dione, dipphen = 4,7-diphenyl-1,10-phenanthroline), has been synthesized and applied to organic electroluminescent (EL) devices as an emitting and electron-transporting material. The EL device structure can be described as indium tin oxide (ITO)/hole-transporting layer (triphenyldiamine derivative (TPD))/emitting layer (Eu(DTP)3(dipphen))/electron transport layer (Alq3)/AlLi (99∶1). The emitting layers were formed by a codeposition technique. The deposited EL devices were observed to emit a bright red light originating from Eu(DTP)3(dipphen) with a maximum luminance of 450 cd m–2 at 15 V and 200 mA cm–2.

A novel europium complex, Eu(MDFP) 3 (phen) (MDFP = 5-methyl-1,3-di-(2-furyl)-1,3-propanedione, phen = 1,10-phenanthroline), was synthesized and applied to an organic electroluminescent (EL) device as an emitting material and an electron-transporting material. The double-layered EL device has been fabricated by using triphenyldiamine derivative (TPD) as a hole-transporting layer and Eu(MDFP) 3 (phen) as an active emitting layer sandwiched between indium—tin oxide (ITO) and an alloy of Al/Li (99:1) electrodes. The deposited EL device was observed to emit a bright red light originating from Eu(MDFP) 3 (phen) with a maximum luminance of 32.0 cd/m 2 at 9 V and 25.7 mA/cm 2 .

Two polyimides, PI(BA-TD) and PI(6FDA-TD), based on an aromatic diamine (TD) and two aromatic dianhydrides (BA, 6FDA) were synthesized. They were characterized by viscosity, FT-IR, and X-ray photoelectron spectroscopy (XPS) measurements. XPS results reveal that the binding energy of C 1s , N 1s , and O 1s in PI(BA-TD) is lower than that in PI(6FDA-TD). The synthesized polyimides form stable and homogeneous thin films on an ITO electrode, functioning as good hole transporting materials for organic electroluminescent (EL) devices. The double-layered EL devices consisting of a hole transporting layer of these polyimides and an emitting layer of the tris(8-quinolinolato)aluminium complex exhibit a peak emission wavelength in the bright green at 521∼525 nm. Furthermore, a maximum luminance of 97 cd/m 2 was achieved at a voltage of 15 V with a current density of 192 mA/cm 2 for the EL device using PI(BA-TD) as a hole transporting layer. The phenomenon of an extended luminance of these EL devices was also found when a voltage higher than 15 V was applied.

A diol containing a protected galactitol analogue was used to synthesize segmented polyurethanes with the usual three-step addition polymerization method. By removing the protecting groups with acid, some novel galactitol analogous segmented polyurethanes (SPUs) were obtained. In these SPUs, poly(ethylene glycol) (PEG), poly(tetramethylene glycol) (PTMG), poly(butadiene) glycol (PBD), and poly(1,6-hexyl-1,2-ethyl carbonate) glycol (PC) were used as the soft segments, while 4,4'-methy)enedipheny) diisocyanate (MDI) and extender butanediol (BD) were used as the hard segments. Furthermore, long alkyl side-chains were also introduced into one of the PTMG-based SPUs. These synthesized polymers were characterized by FT-IR spectroscopy and the structure of the PC-based SPU6 was analyzed by X-ray diffraction. Cast films of the SPUs were characterized for surface properties by measuring the water contact angle and by X-ray photoelectron spectroscopy. From the results of dynamic viscoelasticity and tensile property...

Polyamides (4a-b and 5a-b) were synthesized from interfacial polycondensation of novel diamine containing phosphatidylcholine analogous moiety, hexamethylene diamine with adipoyl chloride, or sebacoyl chloride in the interface of water and carbon tetrachloride at room temperature. The characterizations of synthesized diamine and polyamides were carried out with FT-NMR, or IR spectral method, elemental analysis, and melting point measurements, respectively. These polyamides obtained are insoluble in any normal solvents. From the results of X-ray diffraction analysis and POM observation, it was revealed that the polyamide 4b was prepared with high molecular weight, while polyamide 4a obtained seemed to have low molecular weight. For copolymers 5a and 5b, X-ray reflections from only adipoyl or sebacoyl chloride parts were observed as in crystalline state. In addition, thermal properties were also studied by DSC and transmitted light intensity measurements.

A series of amphiphilic phospholipid analogous acrylamide monomers and homopolymers containing long alkyl chains as the hydrophobic groups and phosphatidylcholine analogues as the hydrophilic groups were used to study the properties of monolayers and multilayers. The P-A isotherms of the monolayers for these monomers and polymers were measured at different temperatures. The temperature and length dependence of alkyl chains, and the difference between monomers and polymers were investigated, respectively. On the other hand, the LB multilayers of all monomers and polymers were prepared. The contact angles of LB films obtained with pure water were also measured.

Three new phospholipid diols, bis[2-(2-hydroxyethyldimethylammonio)ethyl]diethylene octadecylamine diphosphate (BDODP), bis[2-(2-hydroxyethyldimethylammonio)ethyl]diethylene hexadecylamine diphosphate (BDHDP), and bis[2-(2-hydroxyethyldimethylammonio)ethyl]diethylene dodecylamine diphosphate (BDDDP), together with 1,4-butanediol (BD) or ethylenediamine (ED) as chain extender were further incorporated into the prepolymer of poly(butadiene) glycol (PBD) and 4,4‘-methylenediphenyl diisocyanate (MDI). The bulk and surface characteristics of the resulting phospholipid segmented polyurethanes (SPUs) and segmented poly(urethane urea)s (SPUUs) were investigated by infrared (IR), gel permeation chromatography (GPC), attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), electron spectroscopy for chemical analysis (ESCA), and contact angle measurements. The mechanical properties were investigated by dynamic viscoelasticity. The hemocompatibilities of the new polymers were evaluated by plat...

Gel formation of a water-soluble zwitterionic phosphatidylcholine analogous acrylamide monomer, 1 - ( acrylamidomethyl ) -2'-(trimethylammonio)ethyl phosphate (AMP), was examined using N,N'-methylenebisacrylamide as the crosslinking constituent, ammonium persulfate as the initiator, and N,N,N',N'-tetramethyl ethylene diamine as the accelerator at room temperature in water system. The swelling properties of the synthesized hydrogel AMPG were investigated in distilled water at different temperatures, in water-acetone medium with different volume ratios, or in different inorganic salts aqueous of various compositions. Furthermore, lysozyme release behavior of the gel was found to depend on the composition of immersed solutions.

An amphiphilic acrylamide monomer containing a vitamin E moiety as the hydrophobic group and a phosphatidylcholine analogue as the hydrophilic group was newly synthesized in high yield. The radical polymerization was carried out in the presence of α, α′ -azobisisobutyronitrile as an initiator. The obtained monomer and homopolymer were characterized by 1H NMR, IR, and melting points. A stacked bilayer structure was proposed for homopolymer from x-ray diffraction analysis. Furthermore, monolayers of the homopolymer were prepared on the surface of water and were investigated at different temperatures.

Previous studies have shown that curcumin (Cur) can produce potent neuroprotective effects against damage due to spinal cord injury (SCI). However, whether Cur can preserve the function of the blood-spinal cord barrier (BSCB) is unclear. The present study was performed to investigate the mechanism underlying BSCB permeability changes, which were induced by treatment with Cur (75, 150, and 300 mg/kg, i.p.) after compressive SCI in rats. BSCB permeability was evaluated by Evans blue leakage. Motor recovery of rats with SCI was assessed using the Basso, Beattie, and Bresnahan scoring system every day until the 21st days post-injury. The protein levels of heme oxygenase-1 (HO-1), tight junction protein, and inflammatory factors were analyzed by western blots. The expression of the inflammatory factors tumor necrosis factor-α (TNF-α) and nuclear factor-kappaB (NF-κB) mRNA was determined with reverse transcription-polymerase chain reactions. Treatment with Cur (150 and 300 mg/kg) significantly reduced Evans blue leakage into the spinal cord tissue at 24h after SCI. Cur (150 mg/kg) significantly increased HO-1 protein expression. The levels of TNF-α and NF-κB mRNA and protein greatly increased at 24h after SCI, and this increase was significantly attenuated by Cur treatment. ZO-1 and occludin expression was upregulated by Cur (150 mg/kg) treatment after SCI, and this effect was blocked by the HO-1 inhibitor zinc protoporphyrin. Long-term effects of Cur on motor recovery after SCI were observed. Our results indicated that Cur can improve motor function after SCI, which could correlate with improvements in BSCB integrity.

In this paper, we study the band gap properties of two-dimensional piezoelectric phononic crystals with {1-3} connectivity family, in which piezoelectric rods with a square cross-section are embedded in a polymer matrix in a square lattice. The finite element method is applied to calculate the band structures of two polarization modes: the shear mode out-of-plane and the mixed mode in-plane. The effects of the rod rotation on the band gaps are discussed. The numerical results illustrate that the rotation of the square rods have significantly impacts on the band gap.

Previous research works on solid oxide fuel cells (SOFCs) have mainly focused on the large length scale phenomena, such as physical and chemical transport phenomena at macroscale. A new approach is proposed in this work, which combines concepts from all-atom (AA) modeling with coarse-graining (CG) molecular dynamics (MD) method to reveal the replacement mechanism of Yttria-Stabilized Zirconia (YSZ) and establish the nanostructures of a NiO-based anode and an YSZ-based electrolyte. Lattice constants of NiO and YSZ are obtained by special measurements. Nanocrystalline structures of anode and electrolyte material structures under disparate conditions are generated via Atomistic Simulation Environment (ASE). By combining this technique with the local lattice constants, the effect of temperature on crystal formation and the influence of sintering conditions on the volume shrinkage are predicted. The combined AA-CG-MD method is validated and subsequently applied to an equilibrated anode and electrolyte nanostructures with a box length of 50 nm. The resulting nanostructures of the materials show good agreement with the distributions from experiments based on Transmission/Scanning Electron Microscopy (TEM/SEM) techniques, and provide insight into atom/pore distribution and the volume shrinkage at a length scale which is expanded into atomistic/molecular dynamics simulation to capture the best materials’ performance and the balance of oxygen-ion conductivity and material stability.

In this paper, the bandgap properties of three-dimensional holey phononic crystals with resonators are investigated by using the finite element method. The resonators are periodically arranged cubic lumps in the cubic holes connected to the matrix by narrow connectors. The influence of the geometry parameters of the resonators on the bandgap is discussed. In contrast to a system with cubic or spherical holes, which has no bandgaps, systems with resonators can exhibit complete bandgaps. The bandgaps are significantly dependent upon the geometry of the resonators. By the careful design of the shape and size of the resonator, a bandgap that is lower by an order of magnitude than the Bragg bandgap can be obtained. The vibration modes at the band edges of the lowest bandgaps are analyzed in order to understand the mechanism of the bandgap generation. It is found that the emergence of the bandgap is due to the local resonance of the resonators. Spring-mass models or spring-pendulum models are developed in order to evaluate the frequencies of the bandgap edges. The study in this paper is relevant to the optimal design of the bandgaps in light porous materials.

In this study, the proximate composition, free amino acids content and 5′-nucleotides in frozen, canned and salted Agaricus bisporus (A. bisporus) were investigated. We found that the three kinds of A. bisporus products were good sources of protein, with amount varying in the ranges of 16.54–24.35 g/100 g (dry weight). Freezing, canning and salting process, followed by 6 months of storage led to a significant reduction in free amino acids, especially tyrosine, alanine, glutamine and cysteine. There were medium levels of MSG-like amino acids in frozen A. bisporus and canned A. bisporus, and low levels of MSG-like amino acids in salted A. bisporus. The mount of flavor 5′-nucleotides in frozen A. bisporus was higher than that of canned and salted A. bisporus. The present study thus suggests that freezing is beneficial for the preservation of A. bisporus.

Due to the bandwidth constraints in the networked control systems (NCSs), a deadband scheduling strategy is proposed to reduce the data transmission rate of network nodes. A discrete-time model of NCSs is established with both deadband scheduling and network-induced time-delay. By employing the Lyapunov functional and LMI approach, a state feedback H∞ controller is designed to ensure the closed-loop system asymptotically to be stable with H∞ performance index. Simulation results show that the introduced deadband scheduling strategy can ensure the control performance of the system and effectively reduce the node's data transmission rate.

To investigate a model to simulate wheat dry matter accumulation, three wheat cultivars with different tillering abilities were grown at three densities each in a field experiment. Five simulation models with high correlation coefficients for relative dry matter accumulation were established by the method of normalized. Among these models, the Richards equation was the best in fitting and forecasting, i.e., y = 1.1435/(1 + e0.2776 − 4.6558x )1/0.1130, r = 0.9927. Correlation coefficient of grey comprehensive relationship degree between actual dry matter accumulation in occurrence time of maximum rate of dry matter accumulation and dry matter weight was highest, so a higher actual dry matter weight in occurrence time of maximum rate of dry matter accumulation played an important role in stabilizing and improving dry matter weight of wheat.

Amphiphilic acrylamide monomer containing a cholesterol moiety as a hydrophobic group and a phosphatidylcholine analogue as a hydrophilic group was synthesized in high yield. Radical polymerization was carried out in the presence of α,α′-azobisisobutyronitrile (AIBN) as initiator. The obtained monomer and homopolymer were characterized by 1H-NMR, IR and melting point, respectively. The packing structure and thermal properties of the obtained polymer were investigated by X-ray diffraction analysis, DSC measurement and polarizing microscopy observation. It has been proposed that the homopolymer consists of a stacked bilayer structure in a smectic liquid crystalline phase over a wide temperature range. In addition, the monolayers of monomer and homopolymer on the surface of water were investigated at different temperatures and different subphase pH. The optimum condition for preparing stable and order monolayer has been determined as 10 °C and pH 4.0 for a monomer, and over a wide range of temperature (10–30 °C) and pH (pH 4.0–10.0) for a homopolymer.

Polyrethanes, based on 2-[bis(2-hydroxyethyl)methylammoni]ethylstearylphosphate, alone or together with 1,4-butanediol as the chain extender, poly(isoprene) diol and 4,4′-methylenediphenyl diisocyanate, were prepared. These segmented phospholipid polyurethanes were characterized by IR, elemental analyses, and gel permeation chromatography. The polyurethane, with both phospholipid diol and 1,4-butanediol as the chain extender, was further investigated by differential scanning calorimetry, x-ray diffraction, scanning electron microscopy, plasma contact and clotting time. An x-ray diffraction measurement for the polymer shows a intense scattering at 79.3 A corresponding to the length of soft segments, which is hydrophobic poly(isoprene), and a weak diffuse scattering at 5.1 A corresponding to the distance between the hydrophobic poly (isoprene) layers. The hemocompatibilities of the polymer were evaluated by platelet rich plasma contacting studies and by scanning electron microscopy using medical grade poly(vinyl chloride) as control. The hot-pressed films of the polymer exhibit a favorable surface in terms of platelet adhesion, and the morphology of adhered platelets undergoes to a relatively lower degree of variation compared to poly(vinyl chloride). Moreover, the clotting time of the polymer in contact with human platelet rich plasma was 220, 100, and 86 s for the phospholipid-based polyurethane, poly(vinyl chloride), and glass, respectively. © 1996 John Wiley & Sons, Inc.

SUMMARY Three new amphiphilic phospholipid diols containing hydrophilic phosphatidylcholine analogues in the main chains and hydrophobic octadecyl, hexadecyl or dodecyl alkyl groups in the side chains were synthesized. The typical phospholipid diol based on an octadecyl group was further reacted with diisocyanates such as hexamethylene diisocyanate (HDI), 2,4-tolylene diisocyanate (TDI) and 4,4‘-methylenediphenyl diisocyanate (MDI), respectively. Preliminary studies suggest that polyurethane based on MDI shows a viscosity behavior similar to common polyelectrolytes and exhibits a therm decomposition peak at 244°C due to the phospholipid moiety and a melting point at 218°C.

A series of phospholipid diols based on different lengths of alkyl chains such as eicosyl, stearyl, cetyl, lauryl, octyl, and butyl was synthesized and characterized. The phospholipid diols were subjected a polyaddition polymerization with hexamethylene diisocyanate. The haemocompatibilities of the resulting phospholipid polyurethanes were evaluated by platelet rich plasma contacting experiments and viewed by scanning electron microscopy. The polymers with alkyl chains of 20, 18, 16, and 12 carbon atoms showed much better haemocompatibilities than those with alkyl chains of 8 and 4 carbon atoms.

New phospholipid analogous polymers were prepared by radical copolymerizations of 2-(methacryloyloxy)ethyl-2-(trimethylammonio)-ethyl phosphate and poly(ethylene glycol)monomethylether methacrylates (PEGMM) at room temperature, using (NH4)2S2O8 as the initiator and pure water as the solvent. The copolymers obtained were characterized based on their IR, 1H-, and 13C-NMR spectral data and melting point measurements. The molecular weights of these copolymers decrease as the length of the PEGMM side chain increases. These new polymers, which contain phosphatidylcholine analogous groups in their side chains, show viscosity properties similar to typical polyelectrolytes.

A series of new phospholipid analogous acrylamide monomers (4a-e) containing long alkyl chains as hydrophobic groups and containing phosphatidylcholine analogues as hydrophilic group were synthesized in high yields. The homopolymerizations and copolymerization (4b with 4e) were carried out in the presence of a radical initiator. The structures and thermal properties of these polymers were investigated by x-ray diffraction analysis, DSC, and polarizing microscopy measurements. It has been revealed that these homopolymers (5b, 5c, and 5d) which bear saturated long-hydrocarbon chains in the side chains exhibited not only orderly stacked bilayer structures at room temperature but also clear liquid crystalline behavior within a wide temperature range. The viscosity behavior of all polymers was found similar to usual polyelectrolytes in porlar solvent. The polymers obtained were also characterized by 1 H-NMR, IR, and melting point, respectively.

New hydrophobic-hydrophilic microphase-separated block segmented copoly(urethane-urea)s were synthesized by introducing hydrophobic polybutadienes as the soft segments and 4,4′-methylenediphenyl diisocyanate, hexamethylene diisocyanate, ethylenediamine, and a hydrophilic phosphatidylcholine analogue as the hard segments in the backbones of these polymers. The results of ATR-IR and XPS show the coexistence of phosphatidylcholine analogues and polybutadienes on the surface of cast films of the synthesized poly(urethane-urea)s. Furthermore, TEM cross sectional observation of the cast film PBDP-1370 indicates that it possesses a hydrophilic-hydrophobic microphase-separated domain structure.

Two kinds of phospholipid analogous compounds, methacrylate monomers (4a-b) and acrylamide monomers (5a-b), were prepared and polymerized with a radical initiator in water at room temperature. The viscosity behavior of these charged polymers were investigated in the presence or absence of inorganic salts, and the found inherent viscosity [η] of amide polymer (poly7a) is higher than those of ester polymers (poly6a1 and poly6b). On the other hand, the radical copolymerization of monomer 5b with acrylamide (AAm) was also carried out in water. Based on the x-ray analyses, it is proposed that some of the obtained polymers show ordered bilayer structures in condensed phase. Furthermore, the thermal properties were studied by DSC anti TG-DTA measurements.

A novel vinyl monomer 2-{(3-acrylamidopropyl)dimethyl ammonio}ethyl 2'-isopropyl phosphate (AAPI) having phosphatidylcholine analogous moiety and a series of new acrylamide monomers containing two long alkyl chains [stearyloleylacrylamide (SOAAm), distearylacrylamide (SSAAm), and n-docosyloleylacrylamide (DOAAm)] were synthesized and characterized. The polyacrylamides (Va, Vb, and Vc) were obtained from radical copolymerization of SOAAm, SSAAm, or DOAAm with AAPI in the presence of AIBN as an initiator. The investigations of these copolymers were carried out by x-ray analysis method, DSC, TG-DTA, and viscosity measurement, respectively. The copolymer Vb containing distearyl groups as hydrophobic side chains shows a crystalline state at room temperature, and the ordered structure disappears at high temperature. The phase transition from a crystalline state to a liquid-crystalline state was observed obviously only for copolymer Vb. In addition, the Π-A isotherms and A-T isobars of these copolymers were measured and their stable LB films were also prepared.

Poly(sodium glutamate) (DP = 160) was modified by sheep brain L-a-phosphatidylethanolamine with about 65% substitution in side chains via the active ester method. The structure of the modified polypeptide was characterized by its IR and 1 H NMR spectral data and elemental analysis. The π-A isotherms of the modified polypeptide at different temperatures and pH were measured. Reproducible Y-type deposition, with a deposition ratio of 0.9 Y-type Langmuir-Blodgett films (30 layers) of the modified polypeptide were also prepared, and lamellar structure, together with an average 32 A thick monolayer was observed by transmission electron microscopy. The formation of β-structure but no α-helix structure for cast film of the modified polypeptide was observed by circular dichroism spectroscopy. A wide-angle X-ray diffraction pattern investigation for the cast film showed a small peak at 2θ = 5.7° and a big peak at 2θ = 20.1°, corresponding to d spacing of 15.5 and 4.4 A, respectively. In addition, investigation of Na + ion and K + ion transport behavior for cast film of the modified polypeptide showed that Na + ion permeating through the cast film was easier than K + ion, and both Na + ion and K + ion permeated through the film easier under acidic conditions (pH 4) than that under neutral conditions (pH 7).

New segmented polyurethanes (SPUs) based on stearyl and phosphatidylcholine analogues were synthesized. The soft segments used in this study were the poly(butadiene) (PBD) glycol, the hard segments...

A novel phosphatidylcholine analogous vinyl monomer 1-(acrylamidomethyl)-2'-(trimethyl ammonio)ethyl phosphate (AMP) was synthesized and characterized. A series of amphiphilic poly- (acrylamide)s were obtained from AMP, and some dialkylacrylamide monomers, by radical copolymeri- zation in the presence of R,R'-azobis(isobutyronitrile) (AIBN). The polyelectrolyte behavior of these copolymers was investigated by their viscosity measurements. Moreover, the structures in condensed phases and thermal properties of these copolymers were investigated by X-ray analysis, DSC measurement, and POM observation. In addition, the phase transitions of monolayers obtained from these amphiphilic copolymers were observed by changing the temperature of the subphase, length of the alkyl chains, and observation times (tob). The LB films were prepared by using the vertical dipping method, and their surface contact angles with pure water were also measured.

Several new polyurethanes bearing fluorene moieties were prepared by addition polymerization of bisphenoxyethanofluorene (BPEF) with diisocyanates such as hexamethylene diisocyanate (HDI), 2,4-tolylene diisocyanate (TDI), and m-xylylene diisocyanate (XDI), respectively. The resulting polyurethanes, BPEF-HDI (PU1), BPEF-TDI (PU2), and BPEF-XDI (PU3), have the number average molecular weight Mn of 11000, 9600, 14000 and intrinsic viscosities [η] of 0.142, 0.085, and 0.120 dL.g -1 , respectively. Moreover, all of the resulting polymers could form brittle transparent films.

Curcumin (Cur) is a major active component of the food flavor turmeric isolated from the powdered dry rhizome of Curcuma longa Linn., which has been used in traditional Chinese medicine to ameliorate intracerebral ischemic damage and reduce brain edema. However, the effects of Cur on the disruption of the blood-brain barrier (BBB) induced by brain ischemia are still unclear. The effects of Cur on the disruption of BBB and changes of tight junction (TJ) proteins induced by oxygen glucose deprivation (OGD) were studied in BBB in vitro. The transendothelial electrical resistance and the flux of horseradish peroxidase in BBB in vitro were measured. The expression and localization of the TJ proteins occludin and zonula occludens-1 (ZO-1) were evaluated by Western blots and immunofluorescence microscopy. The protein levels of heme oxygenase-1 (HO-1) were also analyzed via Western blots. Cur attenuated OGD-induced disruption of paracellular permeability and increased the expression of HO-1 protein in rat brain microvascular endothelial cells (RBMECs). After administration of OGD, the expression of occludin and ZO-1 proteins was restored by Cur, and this effect was blocked by a HO-1 inhibitor, zinc protoporphyrin (ZnPP). Cur protects RBMECs against OGD-induced disruption of TJ and barrier dysfunction via the HO-1 pathway. We propose that Cur is capable of improving the barrier function of BBB under ischemic conditions and this beneficial effect might be reversed by a HO-1 inhibitor, ZnPP.

SummaryLow-density lipoproteins (LDL) is known to protect boar sperm during freezing–thawing, but little information is known about the effects of LDL extracted from different avian egg yolks on post-thaw boar semen quality. The purpose of this study was to compare and analyze the effects of LDL at various concentrations and different species on boar sperm quality after freezing–thawing. LDL extracted from the yolk of hen egg, duck egg, quail egg, pigeon egg or ostrich egg was added to the extender at the concentrations of 0.06, 0.07, 0.08, 0.09 and 0.1 g/ml, respectively, and their effects on frozen–thawed boar sperm quality were assessed. According to all measured parameters, the results showed that sperm motility, acrosome integrity and plasma membrane integrity were 43.20%, 52.57% and 48.13%, respectively, after being frozen–thawed with 0.09 g/ml LDL extracted from pigeon egg yolk. All these quality parameters were higher than that of other groups (P < 0.05). In conclusion, our results confirmed that LDL extracted from pigeon egg yolk had the best cryoprotective effects on frozen–thawed boar sperm among all of the groups supplemented with LDL from five kinds of avian egg in extender. The optimum concentration of LDL extracted from pigeon egg in boar semen freezing extender was 0.09 g/ml.

A phospholipid-like acrylamidic monomer with both a long alkyl chain as the hydrophobic group and a phosphatidylcholine analogue as the hydrophilic group was newly synthesized and characterized. The homopolymerization and copolymerization with acrylamide were carried out in the presence of a radical initiator. The obtained polymers were characterized by FT-NMR, IR, and melting points. From the X-ray diffraction measurements, the structures proposed for monomer, homopolymer, and copolymer are basically constructed from alternately stacked bilayers with hydrophilic and hydrophobic regions of the monomer or the side chain, the bilayer structures of which are similar to that found for lipid bilayers. The thermal properties of monomer and polymers were also studied by DSC measurements.

In this paper, the bandgap properties of three-dimensional holey phononic crystals with Helmholtz resonators are investigated by using the finite element method. The resonators are periodically arranged cubic lumps in the cubic holes connected to the matrix by one narrow connector. In contrast to a system with cubic or spherical holes, which has no bandgaps, systems with Helmholtz resonators can exhibit complete bandgap, which is lower by an order of magnitude than the Bragg bandgap can be obtained. The vibration modes at the band edges of the lowest bandgap are analyzed in order to understand the mechanism of the bandgap generation. It is found that the emergence of the bandgap is due to the local resonance of the resonators. Spring-mass/ pendulum models are developed in order to evaluate the frequencies of the bandgap edges. The study in this paper is relevant to the optimal design of the bandgaps in light porous materials.

Spermatogonial stem cells (SSCs) are the only type of cells that transmit genes to the subsequent generations. The proliferation, cultivation and identification of SSCs in vitro are critical to understanding of male infertility, genetic resources and conservation of endangered species. To investigate the effects of glial cell-derived neurotrophic factor (GDNF) and leukemia inhibitory factor (LIF) on the proliferation of mouse SSCs in vitro, supplement of GDNF and/or LIF were designed to culture SSCs. The testes of 6–8 d mouse were harvested and digested by two-step enzyme digestion method. The SSCs and Sertoli cells were separated by differential plating. Then the SSCs were identified by alkaline phosphatase staining, RT-PCR and indirect immunofluorescence cell analysis. The cellular proliferation capacity was measured by methyl thiazolyl tetrazolium assay. The results showed that addition of 20 and 40 ng/ml of GDNF could strongly promote growth of mouse SSCs (p 0.05). However, the combination of 20 ng/ml GDNF and 1,000 U/ml LIF could significantly enhance the invitro proliferation of mouse SSCs (p

By using the finite element method, the propagation of Lamb waves in sandwich phononic crystal plates is investigated. This structure is composed of a two-dimensional phononic crystal plate coated with two homogeneous substrates on both surfaces. The phononic crystal plate is constituted by a square array of elastic cylinder embedded in a solid matrix. It is shown that some complete band gaps are opened by changing the thickness of the phononic crystal plate, and that the width of the first band gap becomes larger as the thickness increased. The influence of the thickness and material properties of the substrates on the width of the complete band gap is discussed as well. It is noted that the thickness of either phononic crystal plate or substrates plays a key role in tuning the band gaps of the sandwich phononic crystal plates.

Phononic crystals (PCs) are a kind of acoustic composite materials which have periodic structures and exhibit elastic wave (EW) band gaps. Due to their unique properties the phononic crystals have potential applications in acoustic devices and noise control, etc. The effects of both positive and negative Poisson's ratios on the phononic band gaps (PBGs) due to either Bragg scattering or locally resonance in three-dimensional (3D) solid/solid phononic crystals with a simple-cubic (SC) lattice are studied. The band structures are obtained by the finite difference time domain (FDTD) method combined with the fast Fourier transform- (FFT-) based postprocessing method. The numerical results show that Poisson's ratio of the scatterer plays an important role in tuning the PBGs.

In this paper, the band structures of 2D vacuum/solid square phononic crystal slabs with cross-like holes are calculated by using the finite element method. The numerical computation is performed by Comsol Multiphysics 3.5a. The transmission spectra of a finite structure and the eigenmodes for the band edges of the lowest bandgap are also calculated. The results show that no bandgap exists for phononic crystal slabs with square holes; however, by introducing cross-like holes, the degeneracy of the bands are separated and wide bandgaps are generated. The band width to center frequency ratio is about eight times of that for the traditional phononic slab with circular holes by carefully designing the geometry of the cross-like holes. The eigenmodes corresponding to the band edges show that the bandgaps are governed by the flexural wave. The results are relevant to the optimization of the acoustic bandgaps.

In this paper, we present a type of vacuum/solid phononic crystal composed of two-dimensional Helmholtz resonators, which is called Helmholtz resonant phononic crystals. By using the finite element method, bandgaps and vibration modes are studied. The numerical computation is performed by Comsol Multiphysics 3.5a. The results show that complete resonant bandgaps exist for the Helmholtz resonant phononic crystals, and also a lower full bandgap appears for the mixed mode. The results are related to optimization of the acoustic bandgaps.