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In this paper, a new method for quantification of interfacial interactions between a randomly rough particle and membrane surface was proposed. It was found that sludge flocs in a membrane bioreactor were of apparent fractal characteristics, and could be modeled by the modified two-variable Weierstrass-Mandelbrot (WM) function. By combining the surface element integration (SEI) method, differential geometry and composite Simpson's rule, the quantitation method for calculating such interfacial interactions was further developed. The correctness and feasibility of the new method were verified. This method was then applied to evaluate the interfacial interactions between a randomly rough particle and membrane surface. It was found that, randomly rough particle possesses stronger interaction strength than regularly rough particle but weaker strength than smooth particle with membrane surface, indicating significant effects of surface morphology and roughness. The proposed method in this study has broad application prospect in membrane fouling study., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Alzheimer's disease (AD) is the most common dementia and the trigger of its pathological cascade is widely believed to be the overproduction and accumulation of β-amyloid protein (Aβ) in the affected brain. However, effective AD remedies are still anxiously awaited. Recent evidence suggests that curcumin may be a potential agent for AD treatment. In this study, we used 5×FAD transgenic mice as an AD model to investigate the effects of curcumin on AD. Our results showed that curcumin administration (150 or 300 mg/kg/day, intragastrically, for 60 days) dramatically reduced Aβ production by downregulating BACE1 expression, preventing synaptic degradation, and improving spatial learning and memory impairment of 5×FAD mice. These findings suggest that curcumin is a potential candidate for AD treatment.

Objective To express the V1/V2 domain of HIV-1 subtype CRF01_AE gp120 in eukaryotic cells, and then prepare its monoclonal antibody (mAb) and identify its antigen reactivity. Methods Eukaryotic expression vector of pTriEx-3-V1/V2CNE55 was constructed and transiently transfected into HEK293F cell line. The V1/V2-His chimera protein was purified and injected into BALB/c mice. After the fusion between spleen cells of immunized BALB/c mice and myeloma cells SP 2/0, ELISA was used for screening the positive hybridoma cell clones against the V1/V2 recombinant protein. The specificity, titer and type of its mAb were characterized. Results We obtained a stable hybridoma cell line which secreted anti-HIV-1 AE subtype gp120 V1/V2 domain mAb. The ascite titer of the mAb was 1:81 000, and the type of the mAb was IgG1/κ. Western blotting showed that the mAb could recognize recombinant HIV-1 gp120 of different HIV-1 subtypes. Conclusion The study prepared successfully the anti-HIV-1 V1/V2 domain mAb.

Interfacial interactions between foulants and membrane directly determine foulant adhesion and membrane fouling. In this study, surface of sludge foulant particles (flocs) was found to be rough, and could be modeled by a sinusoidal sphere function. A novel method, which combined surface element integration (SEI) method, differential geometry and composite Simpson's rule, was developed to quantify the interfacial interactions between the modeled rough floc surface and membrane surface. Application of the novel method in a membrane bioreactor (MBR) provides broad profiles of quantitative interactions with rough floc surface with separation distance. It is also found that increase in the scaled amplitude of floc surface significantly reduced the interaction strength. Derjaguin's approximation (DA) can be regarded as a special case of the novel method, indicating the extensive application prospect of the novel method. The novel method for interaction calculation was verified to be correct and feasible. Finally, roles of the novel method in membrane fouling research were discussed., (Copyright © 2016 Elsevier Inc. All rights reserved.)

A membrane bioreactor (MBR) was continuously operated to investigate mechanisms of fouling caused by the gel layer in this study. Agar was used as a model foulant for gel layer formation, and filtration resistance of gel layers was systematically assessed. The results showed that gel layer possessed unusually high specific filtration resistance (SFR) and high measured porosity as compared with cake layer. Current knowledge cannot explain the contradiction between high filtration resistance and high porosity of gel layer. A new fouling mechanism based on Flory-Huggins theory was then proposed. Filtration resistance of agar gel layer was found to be independent of pH and ionic strength, but linearly increase with gel thickness. The results are accordant with the mechanism deductions. Simulation of the mechanism model showed that the filtration resistance induced by mixing chemical potential variation was comparable to the experimental data of filtration resistance of agar gel layer, indicating that the proposed mechanism is the predominant mechanism responsible for the high filtration resistance of gel layer. The proposed mechanism was further verified from the bound water viewpoint., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Objectives: An effective AIDS vaccine should elicit protective antibody responses against HIV/simian immunodeficiency virus (SIV) infection. We recently reported that mucosal priming with a replicating modified vaccinia Tiantan virus (MVTTgpe)-based vaccine regimen induces durable protection against pathogenic SIVmac239 infection in rhesus monkeys. Here, we aim to conduct a comprehensive analysis on antigenic determinants recognized by specific antibody responses generated by vaccination and SIVmac239 infection., Methods: A novel yeast surface displayed antigen library of entire SIVmac239 envelope (Env) glycoprotein was established and validated to map the major antigenic determinants (MAD) in monkey sera elicited by vaccination and infection. MAD-directed antibody responses were further analyzed for correlation of protection., Results and Conclusions: The yeast surface displayed library allows the mapping of SIV-specific linear and conformational MAD. The MVTTgpe-based regimen induces antibodies targeting mainly to 6 antigenic domains covering the entire gp160. Critically, this regimen induced a uniquely predominant antibody response against a distinct MAD in variable region 2 (V2) as compared with the Ad5gpe-based vaccine and SIVmac239 infection. This MAD was associated with a higher titer of anti-V2 antibody responses, which was inversely correlated with peak and set-point viral loads. Unexpectedly, the pathogenic SIVmac239 challenge evaded the vaccine-elicited anti-V2 antibody response. Instead of recalling B-cell memory responses to the V2 MAD, viral infection directed anti-V1V2 antibodies primarily to V1 region. Moreover, the anti-V1V2 antibody responses diminished significantly in infected macaques after they enter the stage of simian AIDS. Our findings have critical implications to AIDS vaccine efforts with focus on V2 region.

Penoscrotal entrapment is a rare urological emergency that requires urgent treatment to avoid penile ischaemia and subsequent erectile dysfunction. Non-metallic and thin metallic objects are easily removed via cutting, while thick metallic constricting devices require specialist saws or motorised cutters, all of which may be difficult to locate in the emergency setting. We report a case of a 45-year-old patient who presented with a 48-h history of gross penoscrotal oedema secondary to entrapment by a thick metal ring (internal diameter 55 mm, external diameter 74 mm and thickness 19 mm). The positioning, thickness of the ring, delayed presentation and extensive oedema meant its removal was especially challenging. We improvised a simple, three-step technique (aspiration, strapping and sling) which enabled the metal ring to be removed without the need for specialist equipment. We would encourage others to employ this safe technique in an emergency setting.

The study on the energy characteristics of Casurina equisetifolia community on red earth eolian sandy soil and homogeneous eolian sandy soil in Dongshan County of Fujian Province showed that the standing biomass and energy of Casurina equisetifolia community were 15 681.84 g x m(-2) and 317 795.31 kJ x m(-2) on red earth eolian sandy soil, and 5 129.87 g x m(-2) and 10 575.50 kJ x m(-2) on homogeneous eolian sandy soil, respectively. On homogeneous eolian sandy soil, the gross caloric value of the community ranged from 19.98 kJ x g(-1) to 21.39 kJ x g(-1), of which, dead branch was the highest while root was the lowest, and its percentage was 46.93% (truck) > 16.44%(root) > 13.92% (branch) > 12.28% (dead branch) > 5.87% (bark) > 3.90% (leaf) > 0.66% (fruit). The return amount of litter was 2061.77 kJ x m(-2) x yr(-1), and the net energy productivity was 12662.82 kJ x m(-2) x yr(-1). On red earth eolian sandy soil, the gross caloric value was 19.84 - 21.70 kJ x g(-1), among which, leaf was the highest while root was the lowest, and its percentage was 38.09% (truck) > 19.48% (branch) > 17.09% (root) > 16.86% (leaf) >6.83% (bark) > 0.88% (dead branch) > 0.77% (fruit). The returned amount of litter was 9070.47 kJ x m(-2) x yr(-1), and the net energy productivity was 31 298.70 kJ x m(-2) yr(-1). The standing biomass and energy of Casurina equisetifolia community were higher on red earth eolian sandy soil than on homogeneous eolian sandy soil, mainly because red earth eolian sandy soil had a thinner sandy layer (< 20 cm) and a stronger nutrient and water supplying ability.