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In this work, MoS 2 -based hybrid tubular nanostructures are facilely synthesized via a self-assembly-assisted process and evaluated as a bifunctional electrocatalyst for hydrogen evolution reactions (HERs) and oxygen reduction reactions (ORRs). By simply mixing the reactants under ambient conditions, (NH 4 ) 2 MoS 4 /polydopamine (PDA) hybrid nanospheres are formed. The protonated dopamine is linked to tetrahedral [MoS 4 ] 2- via weak N-H···S and O-H···S interactions, causing the PDA nanospheres merging together and forming nanorods under stirring-induced shear force. Moreover, the oxidative polymerization of dopamine proceeds on the surface of the nanorods, whereas it is prohibited inside the nanorods owing to lack of oxygen, leading to outward diffusion of dopamine and hence cavitation. After annealing, the tubular morphology is perfectly retained, while ultrafine MoS 2 monolayers are formed due to the confinement of the framework. Benefiting from these unique structural features, the MoS 2 /C hybrid nanotubes possess abundant active sites and high surface area, as well as boost electronic and ionic transport, remarkably enhancing their electrocatalytic activities. The onset and half-wave potentials are 0.91 and 0.82 V, respectively, for ORR, close to those of Pt/C. Moreover, low onset potential and small Tafel slope are also observed for HER, demonstrating the potential of the hybrid nanotubes as a promising non-noble metal bifunctional electrocatalyst.

Ultralight and highly elastic reduced graphene oxide (RGO)/lignin-derived carbon (LDC) composite aerogels with aligned micron-sized pores and cell walls are prepared using a facile freeze-drying method. The presence of a small fraction of LDC in the cell walls enhances the interfacial polarization effect while almost maintaining the amount of charge carriers and conductivity of the cell walls, greatly boosting the wave absorption capability of the cell walls. RGO/LDC aerogels also show a greater number of large cell walls with better integrity than RGO aerogels, further improving the multiple reflection ability of the aligned cell walls. Synergistic effects of the multiphase cell walls and the preferred microstructures of the RGO/LDC aerogels lead to their high electromagnetic interference (EMI) shielding effectiveness of 21.3-49.2 dB at an ultralow density of 2.0-8.0 mg/cm 3 . This corresponds to the surface-specific SE (SE divided by density and thickness) up to 53 250 dB·cm 2 /g, which is higher than the values reported for other carbon- and metal-based shields. Furthermore, the critical roles that microstructures play in determining the EMI shielding performance are directly revealed by comparing the shielding performance in directions parallel and normal to cell walls, as well as in an in situ compression process.

Flexible waterborne polyurethane (WPU)/silver nanowire (AgNW) nanocomposites with unidirectionally aligned micrometer-sized pores are fabricated using a facile freeze-drying process, and their dimensions, densities, and AgNW contents are easily controllable. The high-aspect-ratio AgNWs are well-dispersed in the nanocomposite cell walls, giving the nanocomposites good compression strength and excellent electrical conductivity even at very low densities. The large conductivity mismatch between the AgNWs and WPU also induces substantial interfacial polarization that benefits the absorption of electromagnetic (EM) waves, whereas the aligned cell walls promote multireflections of the waves in the porous architectures, further facilitating the absorption. The synergistic actions of the AgNWs, WPU, and unidirectionally aligned pores lead to ultrahigh EM shielding performance. The X-band shielding effectiveness (SE) of the nanocomposites is 64 and 20 dB at the densities of merely 45 and 8 mg/cm 3 , respectively, and ultrahigh surface specific SE of ∼1087 dB cm 3 /(g mm) is achieved with only 0.027 vol % AgNWs, demonstrating that they are promising ultralight, flexible, mechanically robust, high-performance EM shielding materials.

This paper examines the effect of surface treatment and filler shape factor on the fracture toughness and elastic modulus of epoxy-based nanocomposite. Two forms of nanofillers, polydopamine-coated montmorillonite clay (D-clay) and polydopamine-coated carbon nanofibres (D-CNF) were investigated. It was found that Young's modulus increases with increasing D-clay and D-CNF loading. However, the fracture toughness decreases with increased D-clay loading but increases with increased D-CNF loading. Explanations have been provided with the aid of fractographic analysis using electron microscope observations of the crack-filler interactions. Fractographic analysis suggests that although polydopamine provides a strong adhesion between the fillers and the matrix, leading to enhanced elastic stiffness, the enhancement prohibits energy release via secondary cracking, resulting in a decrease in fracture toughness. In contrast, 1D fibre is effective in increasing the energy dissipation during fracture through crack deflection, fibre debonding, fibre break, and pull-out., Competing Interests: The authors declare no conflict of interest.

An electrofluorochromic (EFC) conjugated copolymer (PEFC) containing carbazole and benzothiadiazole (BTD) moieties is synthesized through Suzuki coupling followed by electrochemical polymerization, resulting in a nanoporous EFC polymer electrode. The electrode exhibits high sensitivity and selectivity in the EFC detection of cyanide anions (CN(-)) in largely aqueous electrolyte (67 vol % water) because electrochemical oxidation of PEFC leads to significant fluorescence quenching, and the presence of different concentrations (1 to 100 μM) of CN(-) in the electrolyte can weaken the oxidative quenching to substantially different extents. Although PEFC is hydrophobic in the neutral state, it is converted to radical cation/dication states upon oxidation, rendering the PEFC some hydrophilicity. Moreover, its nanoporous morphology provides a large surface area and short diffusion distance, facilitating the movement of CN(-) in the electrolyte into the PEFC film to interact with receptors. Density functional theory calculations show that the noncovalent interaction between electron-deficient BTD and nucleophilic CN(-) is energy favorable in the oxidized states in both aqueous and organic media, suggesting that the specific π(-)-π(+) interaction plays the main role in the CN(-) detection., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Inspired by the high transition-metal-ion content in mussel glues, and the cross-linking and mechanical reinforcement effects of some transition-metal ions in mussel threads, high concentrations of nickel(II), cobalt(II), and manganese(II) ions have been purposely introduced into the reaction system for dopamine polymerization. Kinetics studies were conducted for the Ni(2+)-dopamine system to investigate the polymerization mechanism. The results show that the Ni(2+) ions could accelerate the assembly of dopamine oligomers in the polymerization process. Spectroscopic and electron microscopic studies reveal that the Ni(2+) ions are chelated with polydopamine (PDA) units, forming homogeneous Ni(2+)-PDA complexes. This facile one-pot approach is utilized to construct transition-metal-ion-PDA complex thin coatings on graphene oxide, which can be carbonized to produce robust hybrid nanosheets with well-dispersed metallic nickel/metallic cobalt/manganese(II) oxide nanoparticles embedded in PDA-derived thin graphitic carbon layers. The nickel-graphene hybrid prepared by using this approach shows good catalytic properties and recyclability for the reduction of p-nitrophenol., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

In this work, bundles of rutile TiO₂ nanoneedles/nanorods are hydrothermally grown on carbon nanofibers (CNFs), forming free-standing mats consisting of three dimensional hierarchical nanostructures (TiO₂-on-CNFs). Morphologies and structures of the TiO₂-on-CNFs are studied using a field-emission scanning electron microscope (FESEM), transmission electron microscope (TEM), X-ray diffractometer (XRD) and thermogravimetric analyzer (TGA). Their electrochemical properties as electrodes in lithium ion batteries (LIBs) are investigated and correlated with the morphologies and structures. It is shown that the lateral size of the TiO₂ nanoneedles/nanorods ranges from a few nanometers to tens of nanometers, and increases with the hydrothermal temperature. Small interspaces are observed between individual nanoneedles/nanorods, which are due to the diverging arrangement of nanoneedles/nanorods induced by growing on the convex surface of nanocylinders. It is found that the growth process can be divided into two stages: initial growth on the CNF surface and further growth upon re-nucleation on the TiO₂ bundles formed in the initial growth stage. In order to achieve good electrochemical performance in LIBs, the size of the TiO₂ nanostructures needs to be small enough to ensure complete alloying and fast charge transport, while the further growth stage has to be avoided to realize direct attachment of TiO₂ nanostructures on the CNFs, facilitating electron transport. The sample obtained after hydrothermal treatment at 130 °C for 2 h (TiO₂-130-2) shows the above features and hence exhibits the best cyclability and rate capacity among all samples; the cyclability and rate capacity of TiO₂-130-2 are also superior to those of other rutile TiO₂-based LIB electrodes.

Azulene-containing conjugated polymers with near-infrared absorption up to 1.5 μm and beyond are achieved by treating with trifluoroacetic acid (TFA). Density functional theory calculations reveal that the near-infrared absorption arises from a strong intramolecular charge transfer transition on the polymer backbone, and the near-infrared absorption can be tuned by the degree of protonation. Furthermore, TFA treated polymers show a ten-fold enhancement in electrochromic contrast and significantly improved switching stability, suggesting that these polymers are promising candidates for fabrication of the first generation organic near-infrared devices., (Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Zinc oxide (ZnO) nanorods coated with silver (Ag) film on a polyethylene terephthalate (PET)flexible substrate were used as the photo anode for water splitting. The hybrid nanostructures were prepared via low-temperature hydrothermal growth and electron beam evaporation. The effects of plasmonic enhanced absorption, surface recombination inhibition and improved charge transport are investigated by varying the Ag thickness. Light trapping and absorption enhancement are further studied by optimizing the curvature of the PET substrates. The maximum short circuit current density (JSC, 0.616 mA cm -2) and the photoelectron conversion efficiency (PCE, 0.81%) are achieved with an optimized Ag film thickness of 10 nm and substrate bending radius of 6.0 mm. The maximum JSC and PCE are seven times and ten times, respectively, higher than those of the bare ZnO nanorods on flexible substrates without bending. The overall PEC performance improvement is attributed to the plasmonic effects induced by Ag film and improved charge transport due to inhibition of ZnO surface charge recombination. Enhanced light trapping (harvesting) induced by bending the PET substrates further improved the overall efficiency.

1D hierarchical tubular MnO(2) nanostructures have been prepared through a facile hydrothermal method using carbon nanofibres (CNFs) as sacrificial template. The morphology of MnO(2) nanostructures can be adjusted by changing the reaction time or annealing process. Polycrystalline MnO(2) nanotubes are formed with a short reaction time (e.g., 10 min) while hierarchical tubular MnO(2) nanostructures composed of assembled nanosheets are obtained at longer reaction times (>45 min). The polycrystalline MnO(2) nanotubes can be further converted to porous nanobelts and sponge-like nanowires by annealing in air. Among all the types of MnO(2) nanostructures prepared, tubular MnO(2) nanostructures composed of assembled nanosheets show optimized charge storage performance when tested as supercapacitor electrodes, for example, delivering an power density of 13.33 kW·kg(-1) and a energy density of 21.1 Wh·kg(-1) with a long cycling life over 3000 cycles, which is mainly related to their features of large specific surface area and optimized charge transfer pathway.

Mice with chronic graft-versus-host disease (cGVHD) induced by transferring parental BALB/C lymphocytes into (C57BL/6 × BALB/C) F1 (CBF1) hybrids, develop a syndrome characterized by B-cell hyperactivity, autoantibody production, and immune complex-mediated glomerulonephritis. In this model, we evaluated the role of leflunomide on the development of lupus nephritis in system autoimmunity. Daily administration of leflunomide (15 mg/kg/d) from 2 weeks after cGVHD induction can dramatically reduce the production of autoantibodies and immune complex deposition in the kidney, leading to relieved kidney damage and reduced mortality. The therapeutic effect of leflunomide on the lupus-prone mice was partially due to the inhibition of TLR9 signaling pathway, which was an important component of innate immune system.

A carbon/SnO(2)/carbon core/shell/shell hybrid nanofibrous mat was successfully prepared via single-spinneret electrospinning followed by carbonization and hydrothermal treatment. The morphology and structure of carbon/SnO(2)/carbon hybrid nanofibers were characterized by field-emission scanning electron microscopy, transmission electron microscopy, thermogravimetric analysis, wide-angle X-ray diffraction and X-ray photoelectron spectroscopy, and their electrochemical properties were studied as an anode in lithium ion batteries (LIBs). It is shown that the designed hybrid nanofibrous mat exhibits excellent electrochemical properties, including high reversible capacity with high columbic efficiency and impressive rate capacity. The greatly enhanced electrochemical performance is mainly due to the morphological stability and reduced diffusion resistance, which are induced by both the carbon core and deposited carbon skin. Furthermore, the embedded and de-aggregated SnO(2) nanoparticles in the carbon phase, which are less than 10 nm in size, provide large numbers of reaction sites for lithium ions and ensure complete alloying with them.

Solid polymer electrolytes with excellent ionic conductivity (above 10(-4) S cm(-1)), which result in high optical modulation for solid electrochromic (EC) devices are presented. The combination of a polar host matrix poly(vinylidene fluoride-trifluoroethylene) P(VDF-TrFE) and a solid plasticized of a low molecular weight poly(ethylene oxide) (PEO) (M(w)≤ 20,000) blended polymer electrolyte serves to enhance both the dissolution of lithium salt and the ionic transport. Calorimetric measurement shows a reduced crystallization due to a better intermixing of the polymers with small molecular weight PEO. Vibrational spectroscopy identifies the presence of free ions and ion pairs in the electrolytes with PEO of M(w)≤ 8000. The ionic dissolution is improved using PEO as a plasticizer when compared to liquid propylene carbonate, evidently shown in the transference number analysis. Ionic transport follows the Arrhenius equation with a low activation energy (0.16-0.2 eV), leading to high ionic conductivities. Solid electrochromic devices fabricated with the blended P(VDF-TrFE)/PEO electrolytes and polyaniline show good spectroelectrochemical performance in the visible (300-800 nm) and near-infrared (0.9-2.4 μm) regions with a modulation up to 60% and fast switching speed of below 20 seconds. The successful introduction of the solid polymer electrolytes with its best harnessed qualities helps to expedite the application of various electrochemical devices., (This journal is © the Owner Societies 2011)

A facile biomimetic method was developed to enhance the interfacial interaction in polymer-layered silicate nanocomposites. By mimicking mussel adhesive proteins, a monolayer of polydopamine was constructed on clay surface by a controllable coating method. The modified clay (D-clay) was incorporated into an epoxy resin, it is found that the strong interfacial interactions brought by the polydopamine benefits not only the dispersion of the D-clay in the epoxy but also the effective interfacial stress transfer, leading to greatly improved thermomechanical properties at very low inorganic loadings. Rheological and infrared spectroscopic studies show that the interfacial interactions between the D-clay and epoxy are dominated by the hydrogen bonds between the catechol-enriched polydopamine and the epoxy.

The electrodes with the hierarchical nanoarchitectures could offer a huge increase in energy storage capacity. However, the ability to achieve such hierarchical architectures on a multiple scale still has remained a great challenge. In this paper, we report a scalable self-assembly strategy to create bioinspired hierarchical structures composed of functionalized graphene sheets to work as anodes of lithium-ion batteries. The resulting electrodes with novel multilevel architectures simultaneously optimize ion transport and capacity, leading to a high performance of reversible capacity of up to 1600 mAh/g, and 1150 mAh/g after 50 cycles. Importantly, the process to fabricate such hierarchical structures is facile, low-cost, green, and scalable, providing a universal approach for the rational design and engineering of electrode materials with enhanced performance, and it may have utility in various applications, including biological scaffold, catalysis, and sensors.

The strong ability of polyhedral oligomeric silsesquioxane (POSS) to aggregate in nonsolvents makes it interesting to study the self-assembly behaviors of polymer-POSS hybrids. Telechelic poly(styrene-ran-sodium styrenesulfonate) with POSS as the end groups was prepared via end-capping of anionic living polystyrene chains with POSS followed by a mild sulfonation. The morphology and association properties of this new amphiphilic hybrid in an aqueous solution were investigated by dynamic and static light scattering, transmission electron microscopy and atomic force microscopy. The studies reveal that the strong aggregation propensity of POSS leads to a low critical micelle concentration and induces the aggregation of micelles. Hollow supermicellar structures can be observed at a low concentration of 1 mg/mL., (© 2011 American Chemical Society)

Hybrid electrochromic materials were readily synthesized via copolymerization of aniline with p-phenylenediamine-functionalized single-walled carbon nanotubes (SWCNTs) in the presence of poly(styrene sulfonate) (PSS) dopant in an aqueous medium. Polyaniline (PANI)-grafted SWCNTs are formed, and they are uniformly dispersed in the PANI/PSS matrix. Impedance analysis shows that the charge-transfer resistances of the hybrids at all states are reduced drastically with increasing SWCNT loading. With 0.8 wt % SWCNTs, the charge-transfer resistances of the hybrid at +1.5 and -1.5 V are only about 20% and 12% of those of PANI/PSS, respectively, which is due to the greatly increased redox reactivity given by the enhanced electron transport in the hybrid and further doping function of the SWCNTs. The remarkable increase in redox reactivity leads to much enhanced electrochromic contrast from 0.34 for PANI to 0.47 for PANI-SWCNT-0.8%.

Poly(methacrylic acid)-grafted hollow silica vesicles (PMAA-g-hollow silica vesicles) were obtained through a grafting-from approach. PMAA brushes were formed by performing atom-transfer radical polymerisation of sodium methacrylate with an initiator attached to the hollow silica spheres. PMAA-g-hollow silica vesicles were characterised by using TEM, thermogravimetric analysis (TGA) and FTIR spectroscopy. pH-dependent ξ potential and (1)H NMR spectra of PMAA-g-hollow silica vesicles were measured, and the results indicated that MAA brushes in PMAA-g-hollow silica vesicles had a lower ionisation degree and low solubility in acidic aqueous solution, for example, pH 3.4, but a higher ionisation degree and high solubility when the pH was higher than 7. Also it was demonstrated that calcein blue and fluorescein isothiocyanate (FITC) labelled dextran (M(n):10 kDa) could be encapsulated in the interiors of the PMAA-g-hollow silica vesicles with a negligible amount in PMAA brushes at pH 2, and pH-triggered release of calcein blue and FITC-labelled dextran from PMAA-g-hollow silica vesicles was observed at pH 7.4., (Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Carbon-SnO(2) core-shell hybrid nanofibers were prepared via single-spinneret electrospinning and subsequent heat treatment. The Kirkendall effect during the heat treatment is found to be responsible for the formation of core-shell morphology. The route is proven to be generic for fabrication of carbon-metal oxide or carbon-metal core-shell nanofibers, and corresponding nanotubes.

A reverse-barrier technique is used to enable the treatment of electrospun poly(vinylidene fluoride) nanofibrous membranes with supercritical carbon dioxide. The treatment induces the formation of nanopores and extended-chain β crystallites of small lateral dimensions in the nanofibers. It also creates interfiber junctions, resulting in a remarkable improvement in mechanical properties of the membranes. The treated membranes are able to retain their shape very well after loading with an ionic liquid (IL). The ionic conductivity of the IL-loaded membrane is very close to that of the neat IL., (Copyright © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Lupus nephritis (LN) is a common secondary glomerular disease with diverse clinical manifestations and pathology. We retrospectively analyzed the clinical manifestations and pathology of 82 hospitalized LN patients (73 females and nine males) during February 2004 to February 2009. The mean age at disease onset of male patients was much younger than female patients (27.6 +/- 6.8 vs. 35.5 +/- 13.9). The kidney biopsy showed that more than 50% was IV-type LN. The II- and III-type LN were also common; their clinical manifestations were common in nephritic syndrome and (or) asymptomatic urinary abnormalities, whereas IV- and V-type LN usually presented nephrotic syndrome. Simultaneously, we investigated that the highest incidence rates of anemia and chronic renal failure were observed in IV- and IV + V-type LN. What was more, we found that serum creatinine level was higher; the interstitial involvement was more severe with renal biopsy. The serum creatinine level and renal interstitial lesions were positively correlated. Our study showed that the different pathologic phenotypes of LN were correlated with the specific clinical manifestations. However, the conclusion should be confirmed by large-scale prospective research.

This paper reports the packing structures of two types of polyhedral oligomeric silsesquioxane (POSS)-imidazolium surfactants with different molecular rigidity in the intergalleries of montmorillonite clay. Wide-angle X-ray scattering (WAXS) and molecular modeling studies suggest that the POSS-imidazolium cations have a bilayer packing structure in clay with the long axes of the molecules largely tilted with respect to the basal plane. Direct evidence for the bilayer structure is provided by transmission electron microscopy (TEM). WAXS and differential scanning calorimetry (DSC) results indicate that the relatively flexible POSS-imidazolium cation is able to form a two-dimensionally ordered structure in the clay intergalleries, while the relatively rigid one exhibits a disordered structure in clay. Furthermore, with reducing surfactant loading, the clay modified with the rigid surfactant exhibits increased interlayer d-spacings probably because the surfactant is able to take more extended conformation at lower loadings. With its low organic content and disordered surfactant packing structure, the clay modified with the rigid surfactant also exhibits excellent thermal and thermo-oxidative stabilities.

Polymer electrolyte is an important component in many multilayer devices such as batteries, fuel cells, and electrochromic devices. The effects of polymer electrolyte solidification on the ionic movement and device performance are presented based on near-infrared (IR) (860-2500 nm) electrochromic (EC) devices using the conducting polymer polyaniline. EC devices using electrolyte with polar polymer host of P(VDF-TrFE) show stable and reversible light modulation up to 65% in gel state and 30% in solid state. This is significantly improved when compared to devices with solidified nonpolar polymer host which retains less than 10% light modulation. Electrochemical impedance combined with in situ light modulation measurement identifies various key characteristics exerted by the electrolyte states on device performance. Gel-state devices are affected by the amount of dissociated ions while ionic movement in the electrolyte bulk and through the electrolyte/EC material interface dictates the light modulation in semisolid devices. For solid-state devices, electronic leakage, ionic dissociation, and interaction with electrochrome molecules have been found to limit the operation.

Polyvinylidene difluoride (PVDF) solutions containing a very low concentration of single-walled carbon nanotubes (SWCNTs) and multiwalled carbon nanotubes (MWCNTs) of similar surface chemistry, respectively, were electrospun, and the nanofibers formed were collected using a modified rotating disk collector. The polymorphic behavior and crystal orientation of the nanofibers were studied using wide-angle X-ray diffraction and infrared spectroscopy, while the nanotube alignment and interfacial interactions in the nanofibers were probed by transmission electron microscopy and Raman spectroscopy. It is shown that the interfacial interaction between the SWCNTs and PVDF and the extensional force experienced by the nanofibers in the electrospinning and collection processes can work synergistically to induce highly oriented beta-form crystallites extensively. In contrast, the MWCNTs could not be well aligned along the nanofiber axis, which leads to a lower degree of crystal orientation.

Water-dispersible polyelectrolyte multilayers (PEM) were obtained by layer-by-layer assembly of poly(allylamine hydrochloride) (PAH) and poly(sodium 4-styrene sulfonate) (PSS) on water-soluble poly(ethylene glycol)- graft-multiwalled carbon nanotubes (PEG- g-MWNTs), and their structures were investigated using solution (1)H NMR. It was clearly shown that some segments of the adsorbed topmost layers formed in layer-by-layer assembly processes are still highly mobile in aqueous solution, and these segments are totally compensated by subsequent coatings of the oppositely charged layers to form ionically cross-linked polyelectrolyte complexes (PEC) layers; it was demonstrated that the ionization behaviors of the highly mobile segments of the topmost PAH layers are similar to those in solution rather than those in the bulk multilayers at different pH. Furthermore, the similarity among the PEM on substrates and the PEC colloids prepared under similar conditions in solution was supported by solution (1)H NMR results, and the unequal stiochiometry of the cationic group from PAH and the anionic group from PSS in the cores of the PEC colloids in solution was identified from solution (1)H NMR results using PEG as external references. On the basis of these, it is suggested that the PEC layers in PEM formed from coating of the adsorbed topmost PAH layers with PSS solution contain excess PSS, and reversely those formed from coating of the adsorbed topmost PSS layers with PAH solution contain excess PAH. Hence a new description of PEM is put forward that the polyelectrolyte multilayers are composed of alternate layers excess either in PSS or in PAH.

Background: Our previous study has shown that porcine antigen-primed and CD4+ T cell-activated macrophages are capable of recognition and rejection of porcine xenografts after adoptive transfer. However, whether this is an absolute xenograft specific rejection remains to be confirmed., Methods: Mouse islet allografts and neonatal porcine islet cell cluster (NICC) xenografts were admixed and transplanted under the left kidney capsule, and NICC xenografts alone were transplanted under the right kidney capsule of strepotozotocin-induced diabetic NOD-SCID mice. After achievement of normoglycemia, the NOD-SCID recipients were transferred with macrophages purified from NICC transplant NOD-SCID mice reconstituted with CD4+ T cells. Five weeks after macrophage transfer the left kidney with the admixed grafts were removed. Graft survival and function following macrophage transfer was assessed by blood glucose measurement and immunohistochemistry., Results and Conclusions: Adoptive transfer with activated macrophages did not affect the normalized blood glucose levels in NOD-SCID recipients of admixed grafts until left nephrectomy 5 weeks post-macrophage transfer. Insulin-positive and porcine C-peptide-negative mouse islets were detected in the admixed grafts. The surviving mouse islets in the admixed grafts were surrounded but not infiltrated by macrophages. The nephrectomized recipients demonstrated sustained hyperglycemia and completely destroyed NICC xenografts in their remaining right kidneys 8 weeks after macrophage transfer. Taken together, these data provide direct evidence of porcine islet xenograft specific rejection by activated macrophages.

The influence of clay surface modification on the polymorphism behavior of poly(ethylene naphthalate) (PEN)/clay nanocomposites was investigated via in situ Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction. The results show that untreated clay has a heterogeneous nucleating effect on PEN and favors the beta-crystal form, while the surfactant 1-hexadecyl-2,3-dimethylimidazolium (IMC16) has a plasticization effect and tends to enhance the kinetically favored alpha-phase instead. In contrast, the nanocomposite (PEN/IMC16-MMT) formed from IMC16-treated clay (IMC16-MMT) exhibits a strong temperature-dependent polymorphic behavior, with the beta-phase being more favored at 200 degrees C, but the alpha-phase being preferred instead at 180 degrees C. In situ FTIR spectroscopy of PEN/IMC16-MMT reveals an abrupt change in the concentration of alpha- and beta-"crystalline conformers" between the two temperatures during the induction period of crystallization. This is attributed to the hindered formation of stable nuclei at the organoclay surface. In addition, surfactant degradation gives rise to a highly plasticized polymer/organoclay interface. The combination of the hindered heterogeneous nucleation and plasticization effects gives rise to the unique temperature-dependent polymorphism behavior in PEN/IMC16-MMT.

Thermally stable organically modified clays based on 1,3-didecyl-2-methylimidazolium (IM2C10) and 1-hexadecyl-2,3-dimethyl-imidazolium (IMC16) were used to prepare poly(ethylene naphthalate) (PEN)/montmorillonite (MMT) nanocomposites via a melt intercalation process. Examination by X-ray diffraction and transmission electron microscopy indicates that an intercalated nanocomposite was formed with IMC16-MMT, while unmodified MMT (Na-MMT) and IM2C10-MMT are generally incompatible with PEN. Thermogravimetric analysis reveals that the peak derivative weight loss temperature of the intercalated PEN/IMC16-MMT was more than 10 "C higher compared to neat PEN, PEN/Na-MMT, or PEN/IM2C10-MMT. Dynamic mechanical analysis also showed that a more significant improvement of the storage modulus was achieved in the better dispersed PEN/IMC16-MMT. The effect of annealing on the dynamic storage modulus of the hybrids is also investigated.

Poly(ethylene terephthalate) (PET)/Clay hybrids were prepared via in situ polymerization, in which the clay was modified with 12-aminododecanoic acid (ADA). Three types of bifunctional compounds were introduced into the system, respectively, as compatibilizers between PET and ADA-Clay. The three compounds contain 1 degree, 2 degree, and 3 degree amino groups, respectively, that could form ionic complex with carboxylic acid of ADA. They also contain an ester group that could react with PET chains through transesterification. The results show that adding the compound with 3 degree amino group can improve clay dispersion significantly, while the ones with 1 degree and 2 degree amino groups are not effective compatibilizers. The possible underlying mechanism is discussed.

[structure: see text] Tetrahedral precursors of tetra(N-alkyl-3-bromocarbazole-6-yl)silanes (1-3), which were amorphous with T(g) being adjustable by changing the chain length of the N-substitutent, were developed. Fluorene-conjugated glassy compound 4 and hyperbranched polymer 5 were synthesized from the precursors via Suzuki coupling reaction. 4 and 5 emitted blue light efficiently in the condensed state with high quantum efficiencies of 80 (4) and 59% (5) and small fwhm (full width at half-maximum) of 48 (4) and 55 nm (5), indicating that they did not pack into detrimental aggregates in the solid state.