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A novel nano-magnetic particles–polyferric sulfate composite coagulant (Fe3O4–PFS) was firstly produced. In this study, the pre-polymerized ion-based PFS and Fe3O4were combined (Fe3O4–PFS) to remove a typical anion dye, Congo Red. Fe3O4–PFS with different molar ratio of PFS (30–100 mg/L) to Fe3O4(0–600 mg/L) showed good performance at the studied pH range, especially at pH 7. The removal value increased from 29.5% to 64.8% when 500 mg/L of Fe3O4was added into 30 mg/L of PFS. The structure and morphology property of the aggregated flocs induced by the composite coagulant were analyzed through instrumental analyses such as Fourier-transform infrared spectroscopy, X-ray diffractometer, scanning electron microscope, a physical property measurement system equipped with vibrating-sample magnetometer, and optical microscope. To study the influence of Fe3O4, fractal dimension (Df) of flocs was investigated by employing image analysis. Finally, the effects and interactions of various factors on the treatment efficiency were studied by response surface methodology coupled with Box–Behnken design. The results showed that the Fe3O4–PFS–CR flocs induced by some local charge interactions and cheating were successfully formed. The flocs of Fe3O4–PFS–CR were lager, compacter, and denser. The surface of it exhibits rougher and more porous. This coagulant significantly decreased the dosage of inorganic coagulant, the flocculation time, and exhibited slighter pH dependence compared with PFS. The respective tests confirmed that the predominant coagulation mechanism of Fe3O4–PFS is the adsorbing-bridging. The method can greatly improve the color removal value. The novel method was highly efficient and environmentally feasible, which it seemed to hold considerable potential in the purification processes of real wastewater.

The undrained interface characteristics of marine clay-structures are key to the design of offshore platforms. However, it is difficult to acquire interfacial shear-induced pore pressure measurements employing conventional interface equipment. This paper introduces an interface instrument that is suitable for evaluating marine soil-structure interface characteristics. The developed device is utilized to investigate the undrained interfacial evolution behavior and softening mechanism of specimens with different moisture contents. The results indicate that the interface undrained strength curve exhibits high stiffness initially, and then declines as the strain level increases. The interfacial soil particles experience two stages: obvious contraction and slight dilatancy tendency. The moisture content response to interface shear resistance is mainly through changing interface adhesion. Additionally, the reduction in contact area caused by interfacial particle dilatancy is the internal inducement of interfacial strain softening. The increase in interfacial soil moisture content caused by water migration is another external inducement. Accordingly, the stress development state in the whole shear process and the variation in free water migration toward the interface are revealed, providing an excellent analytical basis for further investigation of undrained interface behavior.

A major goal of biomedical research is the identification of molecular and cellular mechanisms that underlie memory storage. Here we report a previously unknown signaling pathway that is necessary for the conversion from short- to long-term memory. The mammalian target of rapamycin (mTOR) complex 2 (mTORC2), which contains the regulatory protein Rictor (rapamycin-insensitive companion of mTOR), was discovered only recently and little is known about its function. We found that conditional deletion of Rictor in the postnatal murine forebrain greatly reduced mTORC2 activity and selectively impaired both long-term memory (LTM) and the late phase of hippocampal long-term potentiation (L-LTP). We also found a comparable impairment of LTM in dTORC2-deficient flies, highlighting the evolutionary conservation of this pathway. Actin polymerization was reduced in the hippocampus of mTORC2-deficient mice and its restoration rescued both L-LTP and LTM. Moreover, a compound that promoted mTORC2 activity converted early LTP into late LTP and enhanced LTM. Thus, mTORC2 could be a therapeutic target for the treatment of cognitive dysfunction.

Regeneratable antioxidant property of nanoceria has widely been explored to minimize the deleterious influences of reactive oxygen species. Limited information is, however, available regarding the biological interactions and subsequent fate of nanoceria in body fluids. This study demonstrates a surprising dissolution of stable and ultrasmall (4 nm) cerium oxide nanoparticles (CeO2NPs) in response to biologically prevalent antioxidant molecules (glutathione, vitamin C). Such a redox sensitive behavior of CeO2NPs is subsequently exploited to design a redox responsive drug delivery system for transporting anticancer drug (camptothecin). Upon exposing the CeO2capped and drug loaded nanoconstruct to vitamin c or glutathione, dissolution-accompanied aggregation of CeO2nanolids unleashes the drug molecules from porous silica to achieve a significant anticancer activity. Besides stimuli responsive drug delivery, immobilization of nanoceria onto the surface of mesoporous silica also facilitates us to gain a basic insight into the biotransformation of CeO2in physiological mediums.

Heterotrimeric G(o) is an abundant brain protein required for negatively reinforced short-term associative olfactory memory in DROSOPHILA: G(o) is the only known substrate of the S1 subunit of pertussis toxin (PTX) in fly, and acute expression of PTX within the mushroom body neurons (MB) induces a reversible deficit in associative olfactory memory. We demonstrate here that the induction of PTX within the α/β and γ lobe MB neurons leads to impaired memory acquisition without affecting memory stability. The induction of PTX within these MB neurons also leads to a significant defect in an optimized positively reinforced short-term memory paradigm; however, this PTX-induced learning deficit is noticeably less severe than found with the negatively reinforced paradigm. Both negatively and positively reinforced memory phenotypes are rescued by the constitutive expression of G(o)α transgenes bearing the Cys351Ile mutation. Since this mutation renders the G(o) molecule insensitive to PTX, the results isolate the effect of PTX on both forms of olfactory associative learning to the inhibition of the G(o) activation.

Active learning involves selecting a few critical unlabeled samples for manual and credible labeling to improve the performance of the current classifier. The critical step of active learning is the sample selection strategy. Uncertainty sampling is a well-known sample selection strategy, which involves selecting the samples for which the current classifier is uncertain. For the generalized linear model, these samples are usually distributed around the current classification hyperplane. However, uncertain samples include samples near the current classification hyperplane, and samples far from the current classification hyperplane and the labeled samples. Traditional uncertainty sampling fails to describe the latter, and traditional methods are easily affected by outliers. In this paper, belief functions are used to describe the uncertainty that exists in various samples. Furthermore, we propose a sample selection strategy based on belief functions. Experimental results based on benchmark datasets show that the proposed approach outperforms several classical methods. Through this approach, higher classification accuracy can be achieved using the same number of new labeled samples.