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Viral reservoirs of HIV-1 are a major obstacle for curing AIDS. The novel animal models that can be directly infected with HIV-1 will contribute to develop effective strategies for eradicating infections. Here, we inoculated 4 northern pig-tailed macaques (NPM) with the HIV-1 strain HIV-1NL4.3 and monitored the infection for approximately 3 years (150 weeks). The HIV-1-infected NPMs showed transient viremia for about 10 weeks after infection. However, cell-associated proviral DNA and viral RNA persisted in the peripheral blood and lymphoid organs for about 3 years. Moreover, replication-competent HIV-1 could be successfully recovered from peripheral blood mononuclear cells (PBMCs) during long-term infection. The numbers of resting CD4+ T cells in HIV-1 infected NPMs harboring proviruses fell within a range of 2- to 3-log10 per million cells, and these proviruses could be reactivated both ex vivo and in vivo in response to co-stimulation with the latency-reversing agents JQ1 and prostratin. Our results suggested that NPMs can be infected with HIV-1 and a long-term viral reservoir was formed in NPMs, which might serve as a potential model for HIV-1 reservoir research.

GO/CNTs composite membranes with fine hierarchical nanostructure were facilely fabricated by intercalation with 1D carboxylated multi-walled carbon nanotubes (MWCNTs-COOH) into 2D graphene oxide (GO) nanosheets for efficient organic wastewater treatment. By characterization results of XRD, Raman, FTIR, TEM and water contact angle, MWCNTs-COOH was successfully to be intercalated into GO lamellar interlayers with grafting reactions, which would improve water permeated flux and stability of membrane. The influences of GO/CNTs ratios, loading amounts, CNTs types and support types on the membrane separation performance were systematically investigated towards methylene blue dye solution. For the GO/CNTs composite membranes prepared under the optimized conditions, the permeated flux of 34.4 L m−2 h-1 and rejection over 99.7 % were obtained towards methylene blue solutions under the transmembrane pressure difference of 0.9 bar, respectively. Compared with pristine GO membrane, it exhibited a nearly 10-fold water permeated flux improvement meanwhile maintaining high rejection. Moreover, the electrostatic interaction and size exclusion effects were synergistically contributed to be responsible for the efficiently separation properties of the GO/CNTs membranes towards different positively/negatively charged dyes and neutral organic molecules. Such the GO/CNTs membranes also exhibited good chemical stability for acid resistance with highly efficient separation performance.

Spinel nickel ferrite (NiFe 2 O 4 ) nanoparticles with high specific area and excellent magnetic properties were synthesized via a template-assisted sol – gel method. The effects of template type on the structural properties, magnetic properties, and heating rate are investigated. Results of XRD and TEM indicate that the NiFe 2 O 4 particles synthesized using templates exhibit a typical single phase spinel structure in nano size. The sample using sponge or cotton as template presents the best saturation magnetization (66.6 emu/g) and the lowest coercivity (137.7 Oe), respectively, and their specific surface area is enhanced greatly from 20.1 m 2 /g to 55.7 m 2 /g. It is found that the calculated hysteresis loss agrees well with the measured radio frequency heating rate.

The root cause of the failure of a cracked blade in the low pressure turbine of a nuclear power plant was investigated. The low clearance between the blade and the disk caused a sliding motion, which led to fretting wear during in-service operations. The crack in the blade was determined to have initiated under fretting wear and propagated with high cycle fatigue by means of analyzing the fracture surface of the failed blade. Micro oxide particles were detected from the Electron Dispersive Spectroscopy data analysis at the fatigue initiation position as typical evidence of fretting wear. The stress distribution on the blade in normal service was calculated with a non-linear elastic–plastic finite element method. The analysis results show that the crack initiation location was different with the location of the highest Mises stress. The fretting fatigue crack initiated under a combination of fretting wear and relatively high Mises stress. Designed fretting fatigue experiments were performed with the results that the fatigue life was greatly reduced by the interaction of the loading history and local fretting wear.

The influence of MoSi2 content on the microstructural, mechanical, and electrical properties of MoSi2–RSiC composites was studied. Results showed that the main phases in the MoSi2–RSiC composites were SiC, MoSi2 and Mo4.8Si3C0.6. When the MoSi2 content was below 10%, most of the Mo compounds coated the surface of the coarse SiC particles. At MoSi2 contents >10%, some Mo compounds coated the surface while others filled the pores near the sintering neck between the SiC particles. MoSi2 can also accelerate the re-crystallization process of RSiC. Increases in MoSi2 content resulted in decreases in the porosity of the composite; in contrast, the flexural strength initially increased and then decreased under the same conditions. The flexural strength reached 94.0 MPa when the MoSi2 content was 10%. With increasing MoSi2 content, the volume resistivity of the composites decreased steeply, the electrical conductivity mechanism of it resembled that of a two shunt-wound equivalent circuit.

Nonlinear optical and optical limiting properties of three graphene materials (pure graphene, graphene oxide, reduced graphene oxide) covalently functionalized by zinc phthalocyanine were studied in nanosecond and femtosecond regimes. In nanosecond regime, reduced graphene oxide–phthalocyanine hybrid shows better optical limiting effect than the other two hybrids. In femtosecond regime, graphene oxide–phthalocyanine shows the best nonlinear optical properties among the three hybrid materials. Based on Z-scan and transient absorption measurements, the mechanisms for nonlinear optical property were analyzed for these materials. Compared with the other two hybrids, reduced graphene oxide–phthalocyanine hybrid is a better candidate in the application of optical limiter.

The paper mainly studies the sum-rate performance of limited feedback (LFB) block-diagonalization (BD) in multi-user distributed antenna system (DAS). As the channel state information (CSI) fed back to base station (BS) is limited, multi-user interference (MUI) is caused inevitably because of the quantization error. Considering the influence of the MUI to the capacity of DAS, we propose a parameter of effective sum-rate ratio (ESRR) to denote the capacity offset under the condition of the BS can get perfect CSI and limited CSI first, then we confirm that the approximated ESRR is very close to actual ESRR got through simulations. After that, based on the approximated ESRR, an adaptive minimum bit feedback scheme which can effectively reduce the overhead of feedback channel and the complexity of the system is proposed. Simulation results show the effectiveness of the proposed scheme.

Multi-walled carbon nanotubes covalently functionalized with tetraphenylporphyrin (MWCNT–TPP) with diameter ranges of

Third-order nonlinear optical responses of a heterostructure composed of a planar thick silver film combined with a truncated all-dielectric photonic crystal are studied experimentally. Both open- and closed-aperture Z-scan measurements show a large nonlinear response within the metallic structure using a nanosecond laser. Compared with metal–dielectric photonic crystals with the same thickness of metal, the effective nonlinear optical response of heterostructure can be amplified nearly 3 times of the magnitude, due to the enhancement of fields in the metal under the tunneling mechanism. This configuration containing an isolated flat metal film has particular applications in reduced dimensions, such as surface sensor and microscopy.

One of the remarkable features of the next generation network is the integration of heterogeneous wireless networks, which enables mobile users with multi-mode terminals access to the best available network seamlessly. However, most of previous work only takes account of either maximizing single user's utility or the whole network's payoff, rarely considers the negotiation between them. In this paper, we propose a novel network selection approach using improved multiplicative multi-attribute auction (MMA). At first, an improved MMA method is put forward to define the user's utility. Additionally, user cost is defined by considering allocated bandwidth, network load intensity and cost factor parameter. And last the best suitable network is selected according to the user's performance-cost-ration. Simulation results confirm that the proposed scheme outperforms the existing scheme in terms of network selection's fairness, user's performance-cost-ration, load balancing and the number of accommodated users.

The problem of power allocation in cognitive radio networks plays an important role to improve the efficiency of spectrum utilization. However, most of previous works focus on the power allocation for secondary users in spectrum sharing overlay or spectrum sharing underlay, which needs to frequently handoff between the idle spectrum bands or considers the interference constraints in all spectrum bands respectively. In order to reduce the handoff and fully utilize the spectrum resource, we propose a new spectrum sharing paradigm which not only can just need to adjust the transmit power in spectrum bands instead of frequently handoff between idle spectrum bands, but can fully utilize the spectrum resource as we only consider the interference power constraints in active spectrum bands rather than in all spectrum bands. Then based on this new spectrum sharing paradigm and the constraint conditions, we study the distributed power allocation for secondary users and formulate the optimization problem as a non-cooperative game problem, after that the variational inequality approach is used to solve this game problem and a Nash equilibria solution is got, finally simulation results are illustrated to demonstrate the performance of the proposed scheme.

Nonlinear optical properties of hydroxyl groups modified multi-walled carbon nanotubes (MWNTs-OH) with diameter of 20–30 nm (MWNTs 2030 -OH) dispersed in water, N , N -dimethylformamide (DMF) and chloroform were studied by using Open-aperture Z-scan technique with nanosecond pulse at 532 nm. The influences of solvent, laser pulse-width, on-axis fluence at focus and concentration on nonlinear optical properties of MWNTs 2030 -OH were analyzed in detail to obtain the optimal nonlinear optical response for applications in optical limiters. Nonlinear optical properties of MWNTs-OH with different diameter in DMF were also studied and compared with multi-walled carbon nanotubes in DMF and C 60 in toluene.

An organic solution-processable functionalized graphene hybrid material with oligothiophene (6THIOP-NH-SPFGraphene) has been synthesized. The thermogravimetry analysis data shows that the hybrid is more stable than its parent graphene oxide as observed with an increased onset temperature. Ultraviolet–visible absorption and fluorescence emission data show that the attachment of the electron-acceptor group (graphene oxide sheet) onto the oligothiophene molecules results in an improved absorption than its parent compound in the whole spectral region and an efficient quenching of photoluminescence. The optical limiting properties were studied by using the open-aperture Z-scan measures at 532 nm, and the results show that 6THIOP-NH-SPFGraphene demonstrated a superior optical limiting effect, better than that of the benchmark optical limiting material C60.

With increasing awareness of the importance of renal cortical interstitial fibrosis, interest has focused on the mechanisms that stimulate generation of profibrotic factors including transforming growth factor (TGF)-beta1, by resident cells, such as proximal tubular epithelial cells (PTCs). Infiltration of monocytes, has been implicated in the pathogenesis of a wide variety of renal diseases, however, how interaction between monocytes and PTCs may affect the generation of TGF-beta1 by the resident cell is unknown. We demonstrate that monocytes stimulate TGF-beta1 transcription and protein synthesis by PTCs. This was dependent on direct cell contact and TGF-beta1 transcriptional activation that was dependent on ICAM-1 binding of unstimulated monocytes. This was mimicked by antibody cross-linking of PTC surface ICAM-1. We have previously identified hyaluronan (HA)-based structures on the surface of PTCs, both primary cultures and the HK-2 cell line. Removal of cell-surface HA increased ICAM-1-dependent monocyte binding and stimulation of TGF-beta1 synthesis. Furthermore, we demonstrate that binding of monocytes to HA-based structures on the cell surface of HK-2 cells interferes with this response. In summary, we have demonstrated that HA-based pericellular structures down-regulate proinflammatory and profibrotic responses by modulation of monocyte-driven ICAM-1-dependent cell activation and TGF-beta1 generation.

Copper(II) complexes of high and low melting points, 1,2-bis-(n-octyl-sulphinyl)ethane (α-bose and β-bose), have been synthesized. The complexes were assigned the formulae: [Cu 2 (α-bose) 4 ](ClO 4 ) 4 ( 1 ), [Cu 2 (β-bose) 4 ](ClO 4 ) 4 ( 2 ), [Cu 2 (α-bose) 2 (NO 3 ) 3 ] (NO 3 )·2H 2 O ( 3 ) and [Cu 2 (β-bose) 2 (NO 3 ) 4 ]·H 2 O ( 4 ), on the basis of their elemental analyses, electrical conductance, magnetic measurements (room and variable temperature) and IR studies. Ferromagnetic and binuclear complexe have also been confirmed.