Graphene-based nanostructured hybrid materials for conductive and superhydrophobic functional coatings

A bi-functional, conductive and superhydrophobic, graphene-based nanostructured hybrid material was fabricated. In order to construct the bi-functional hybrid material, carbon nanotubes (CNT) and polyhedral oligomeric silsesquioxane (POSS) were introduced. The water contact angle (WCA) of the graphene/POSS/CNT coating reached about 155 degrees and its conductivity was about 1-10 S/cm. Such graphene-based nanostructured hybrid materials could have great potential as an antistatic and self-cleaning coating in various applications.

Higher harmonic anisotropic flow measurements of charged particles in Pb-Pb collisions at sqrt(s(NN)) = 2.76 TeV

We report on the first measurement of the triangular v3, quadrangular v4, and pentagonal v5 charged particle flow in Pb-Pb collisions at sqrt(s(NN)) = 2.76  TeV measured with the ALICE detector at the CERN Large Hadron Collider. We show that the triangular flow can be described in terms of the initial spatial anisotropy and its fluctuations, which provides strong constraints on its origin. In the most central events, where the elliptic flow v2 and v3 have similar magnitude, a double peaked structure in the two-particle azimuthal correlations is observed, which is often interpreted as a Mach cone response to fast partons. We show that this structure can be naturally explained from the measured anisotropic flow Fourier coefficients.

Conductive behaviour and self-conductance characteristic of carbon nanotubes/functionalized graphene hybrid films

Multi-walled carbon nanotubes (MWCNTs)/Functionalized graphite (FG) hybrid films were fabricated by a simple solution-casting method. The films showed a layered, well-entangled and interconnected porous structure at nanometer scale. Such the nanostructures resulted in the films having the relatively high bulk conductivity and self-conductance characteristics. With increasing MWCNT mass fraction, the conductivity rapidly increased from approximately 10(-9) S/m of the host FG to over 10(-1) S/m. The percolation threshold was found to be about 29.6 wt% of MWCNTs. For the film with 83 wt% MWCNTs the specific capacitance was about 1 F/cm3. The hybrid films are of much higher power factor compared to conventional dielectric capacitors. The energy density of the film with 50 wt% MWCNTs was found to be 0.1 Wh/m3 and the charge-discharge period was very short about 8 seconds. It is believed that the MWCNTs/FG hybrid films have great potential as electrode materials for applications to energy storage.

CD40-specific costimulation blockade enhances neonatal porcine islet survival in nonhuman primates

The widespread clinical implementation of alloislet transplantation as therapy for type 1 diabetes has been hindered by the lack of suitable islet donors. Pig-to-human islet xenotransplantation is one strategy with potential to alleviate this shortage. Long-term survival of porcine islets has been achieved using CD154-specific antibodies to interrupt the CD40/CD154 costimulation pathway; however, CD154-specific antibodies seem unlikely candidates for clinical translation. An alternative strategy for CD40/CD154 pathway interruption is use of CD40-specific antibodies. Herein, we evaluate the ability of a chimeric CD40-specific monoclonal antibody (Chi220) to protect islet xenografts. Neonatal porcine islets (~50,000 IEQ/kg) were transplanted intraportally into pancreatectomized diabetic macaques. Immunosuppression consisted of induction therapy with Chi220 and the IL-2 receptor-specific antibody basiliximab, and maintenance therapy with sirolimus and the B7-specific fusion protein belatacept. Chi220 effectively promoted xenoislet engraftment and survival, with five of six treated recipients achieving insulin-independent normoglycemia (median rejection-free survival 59 days; mean 90.8 days, maximum 203 days). No thromboembolic phenomena were observed. CD40 represents a promising alternative to CD154 as a therapeutic target, and the efficacy of CD40-specific antibodies in islet xenotransplantation warrants further investigation.

A clinical case-control study on the association between mannose-binding lectin and susceptibility to HIV-1 infection among northern Han Chinese population

Mannose-binding lectin (MBL) is a key molecule of the innate immune system and a competent to bind carbohydrates of a variety of microorganisms, resulting in complement activation and opsonophagocytosis against various pathogens. However, there is no systemic investigation on the MBL's role in innate immune responses against HIV-1 infection among northern Han Chinese. This study investigated the association between MBL and HIV-1 infection susceptibility among northern Han Chinese. A total of 91 HIV-1 infected patients and 91 HIV-1 seronegative healthy individuals were recruited. Six polymorphisms of MBL2 gene were genotyped by pyrosequencing. The quantitative measurement of serum MBL concentration and MBL complex activity were performed by ELISA. The CD4+ T-cell counts were determined by flow cytometry. The plasma viral loads of 91 HIV-1 infected patients were determined by bDNA method. The results show that there is an association between MBL and HIV-1 infection susceptibility among northern Han Chinese. The individuals with B variant, low serum MBL concentration and low MBL complex activity are more susceptible to HIV-1 infection.

Down-regulation of TSG101 by small interfering RNA inhibits the proliferation of breast cancer cells through the MAPK/ERK signal pathway

We designed to investigate the effects of down-regulating the tumor susceptibility gene 101 (TSG101) on the proliferation and apoptosis of the human breast cancer MCF-7 cell line, and the role of the MAPK/ERK signal pathway in this process. The siRNA against TSG101 was transfected into the breast cancer MCF-7 cell line using Lipofectamine 2000. After TSG101 knockdown, the proliferation of MCF-7 cells was measured by the MTT assay. The cell cycle distribution and apoptosis were examined by using flow cytometry while cell migration was measured using a transwell assay. The protein level of p-ERK was further assessed by immunofluorescence and western blotting. Our results are as following, the MCF-7 cells transfected with TSG101 siRNA proliferated significantly slower and exhibited significantly increased rates of apoptosis compared to the control cells. In the TSG101 siRNA transfected cells, the percentage of cells in the G₀/G₁ and S phase of the cell cycle was significantly higher and lower, respectively, compared to the control cells. Moreover, the migration ability of TSG101 siRNA transfected cells was lower than the control groups. Lastly, the level of p-ERK protein in TSG101 siRNA transfected cells was significantly decreased compared with the control cells. In conclusion, TSG101 knockdown in breast cancer cells induces apoptosis and inhibits proliferation. The TSG101 depleted cells are arrested at the G₁/S transition of the cell cycle. The migration of breast cancer cells is also impaired by TSG101 siRNA. TSG101 may play a biological role through modulation of the MAPK/ERK signaling pathway in breast cancer.

In-situ observation of atomic processes in Xe nanocrystals embedded in al

Self-organization processes in Xe nanocrystals embedded in Al are observed with in-situ high-resolution electron microscopy. Under electron irradiation, stacking fault type defects are produced in Xe nanocrystals. The defects recover in a layer by layer manner. Detailed analysis of the video reveals that the displacement of Xe atoms in the stacking fault was rather small for the Xe atoms at boundary between Xe and Al, suggesting the possibility of the stacking fault in Xe precipitate originating inside of precipitate, not at the Al/Xe interface.

Centrality dependence of the charged-particle multiplicity density at midrapidity in Pb-Pb collisions at sqrt[s(NN)] = 2.76 TeV

The centrality dependence of the charged-particle multiplicity density at midrapidity in Pb-Pb collisions at sqrt[s_{NN}]=2.76  TeV is presented. The charged-particle density normalized per participating nucleon pair increases by about a factor of 2 from peripheral (70%-80%) to central (0%-5%) collisions. The centrality dependence is found to be similar to that observed at lower collision energies. The data are compared with models based on different mechanisms for particle production in nuclear collisions.

Elliptic flow of charged particles in Pb-Pb collisions at sqrt[S(NN)] = 2.76 TeV

We report the first measurement of charged particle elliptic flow in Pb-Pb collisions at sqrt[S(NN)] =2.76 TeV with the ALICE detector at the CERN Large Hadron Collider. The measurement is performed in the central pseudorapidity region (|η|<0.8) and transverse momentum range 0.2<p t<5.0 GeV/c. The elliptic flow signal v₂, measured using the 4-particle correlation method, averaged over transverse momentum and pseudorapidity is 0.087 ± 0.002(stat) ± 0.003(syst) in the 40%-50% centrality class. The differential elliptic flow v₂ p t reaches a maximum of 0.2 near p t =3 GeV/c. Compared to RHIC Au-Au collisions at sqrt[S(NN)] 200 GeV, the elliptic flow increases by about 30%. Some hydrodynamic model predictions which include viscous corrections are in agreement with the observed increase.

Charged-particle multiplicity density at midrapidity in central Pb-Pb collisions at sqrt[S(NN)] = 2.76 TeV

The first measurement of the charged-particle multiplicity density at midrapidity in Pb-Pb collisions at a center-of-mass energy per nucleon pair √ S NN = 2.76 TeV is presented. For an event sample corresponding to the most central 5% of the hadronic cross section, the pseudorapidity density of primary charged particles at midrapidity is 1584 ± 4(stat) ± 76(syst), which corresponds to 8.3 ± 0.4(syst) per participating nucleon pair. This represents an increase of about a factor 1.9 relative to pp collisions at similar collision energies, and about a factor 2.2 to central Au-Au collisions at √ S NN = 2.76 TeV. This measurement provides the first experimental constraint for models of nucleus-nucleus collisions at LHC energies.

Dietary effects of distillers dried grains with solubles on performance and milk composition of lactating sows

A study was conducted to evaluate the dietary effect of adding increasing concentrations of distillers dried grains with solubles (DDGS) to corn- and soybean meal-based sow lactation diets on sow and litter performance, energy and N digestibility, plasma urea N (PUN), and milk fat and protein concentrations. Mixed-parity sows [n = 307; 221 ± 15 kg of BW, 4.54 parities, litter size of 10.6, and litter weight at birth (alive) of 15.14 kg] were assigned randomly to 1 of 5 dietary treatments: control (CON; corn-soybean meal); 10, 20, and 30% DDGS; and 30% DDGS high-protein (HP) diets. Sows were moved to farrowing rooms on d 109 of gestation and were fed the dietary treatments until weaning. Within each treatment group, feces and urine for energy and N digestibility analysis (from d 10 to 12 of lactation) and blood for PUN analysis and milk fat and protein concentrations (on d 0 and 19 of lactation) were collected from 6 randomly chosen parity 3 to 5 sows. There were no dietary effects (P = 0.10) of DDGS on ADFI of sows and sow backfat change. However, sows fed 30% DDGS HP lost more BW compared with sows fed CON (P < 0.05). There were no dietary effects (P = 0.71) of DDGS on preweaning mortality of piglets, litter weight gain, and piglet ADG. Dietary treatments did not affect (P > 0.05) DE, ME, N retention, or N digestibility of the diets. There were no differences in the concentrations of fat and protein in milk at weaning (d 19) among dietary treatments. Sows fed 20 and 30% DDGS had less (P < 0.05) PUN at weaning (d 19) than sows fed CON and 30% DDGS HP. Inclusion of up to 30% DDGS in a lactation diet did not affect (P > 0.05) sow and litter performance, DE and ME contents of the diets, N retention and digestibility, and milk composition compared with sows fed a corn-soybean meal CON diet. It was concluded that addition of up to 30% DDGS in a lactation diet will support satisfactory sow and litter performance.

Midrapidity antiproton-to-proton ratio in pp collisons at sqrt[s]=0.9 and 7 TeV measured by the ALICE experiment

The ratio of the yields of antiprotons to protons in pp collisions has been measured by the ALICE experiment at sqrt[s]=0.9 and 7 TeV during the initial running periods of the Large Hadron Collider. The measurement covers the transverse momentum interval 0.45<p_{t}<1.05  GeV/c and rapidity |y|<0.5. The ratio is measured to be R_{|y|<0.5}=0.957±0.006(stat)±0.014(syst) at 0.9 TeV and R_{|y|<0.5}=0.991±0.005(stat)±0.014(syst) at 7 TeV and it is independent of both rapidity and transverse momentum. The results are consistent with the conventional model of baryon-number transport and set stringent limits on any additional contributions to baryon-number transfer over very large rapidity intervals in pp collisions.

A study of energy dissipation in exfoliated polyurethane/organoclay nanocomposites

Exfoliated polyurethane (PU)/organoclay nanocomposites were prepared by in situ polymerization of polyol/organoclay mixture, chain extender and diisocyanate. The effect of organoclay on energy dissipation in the exfoliated PU/organoclay nanocomposites during cyclic deformation at strain ratios of 50%, 100% and 200% was investigated experimentally and by molecular dynamics (MD) simulation. The addition of organoclay resulted in extra energy loss in the PU nanocomposites and greater energy dissipation in the exfoliated nanocomposites compared with intercalated ones containing the same percentage of organoclay. With the help of MD simulation, understanding of the energy dissipation arising from the addition of organoclay to the exfoliated PU nanocomposites is now clearer. The nanoplatelets exhibited reversible orientation behaviour at a low strain ratio of 50%, suggesting that the additional energy dissipation may be due to the frictional sliding at the interface between polymer chains and the surfaces of organoclay layers. However, when the sample was subjected to large strain, the orientation of nanoplatelets revealed more irreversible behaviour indicating that the extra energy dissipation is due to both the frictional sliding at the interface and the orientation of the nanoplatelets. The additional energy dissipation was also influenced by the strength of interactions between polymer chains and clay platelets: the stronger interactions, the greater the energy dissipation.