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A magnetic Metal–Organic Framework (MOF) nanocomposite, namely Cu-BTC@Fe3O4 (BTC = 1,3,5-benzenetricarboxylate) was used for magnetically retrievable separation of uranyl (UO22+) in the presence of competitive ions. A significant adsorption amount of 312 mg/g was achieved for uranium over Cu-BTC@Fe3O4 at a pH value of 4.5. Extended X-ray Absorption Fine Structure (EXAFS) analysis indicated that the interaction of Cu-BTC@Fe3O4 with UO22+ is the synergistic coordination of carboxylate groups of BTC ligand, Fe3O4-COOH, and hydrate H2O for UO22+ ions. In addition to identifying a stable and retrievable adsorbent, the results generally elucidate UO22+ removal of MOFs composites. [ABSTRACT FROM AUTHOR]

A three-phase, double-percolating composite with Co2Z ferrite particles and nickel particles embedded in a poly(vinylidene fluoride) matrix was prepared by using a simple low-temperature hot-pressing technique. The large ferrite particles in the composite not only act as the magnetic phase but also present as a high volume fraction discrete (nonpercolating) phase, confining polymer and metallic particles into a continuous double-percolating structure of low volume fraction. With the addition of a small number of magnetic nickel particles, a large enhancement in both initial permeability and dielectric constant of the three-phase composite was observed. This can be explained by effective medium approach and percolation theory. The three-phase composite showed both frequency-independent inductive and capacitive properties in the high-frequency range up to ∼500 MHz. Such a multifunctional magnetic-electric three-phase composite could be used in high-frequency communications and electromagnetic interference filters not only as an inductor but also as a capacitor. [ABSTRACT FROM AUTHOR]

The energy storage density of pure polymers is usually limited by their low intrinsic dielectric constants (ε eff). Integrating polymer matrix with ceramic particles with high ε eff values has been one powerful approach to enhance the ε eff values of polymer composites and thus their energy storage density. In this study, we report a flexible polymer-based composite by introducing Nd-doped BaTiO3 (NBT) nanoparticles (ε eff over 3×105) into the poly(vinylidene fluoride) (PVDF). The phase of PVDF and its dielectric behavior could be adjusted by varying the NBT loadings. Composites including less than 5 vol.% NBT loading exhibited enhanced dielectric constants and maintained high breakdown strength. With a quenching process, the composite delivers a discharged energy density up to 7.91 J/cm3 at an electric field of 350 kV/mm with 2.5 vol.% NBT loading, which is 140% more than that of pure PVDF at the same electric field. [ABSTRACT FROM AUTHOR]

Objective The aim was to explore the influence of exercise prescription on physical health index of female college students. Methods Sixty-six female students of grade 2011 in Kunming Medical University were given the exercise prescription of aerobic exercise combined with small load strength training for one year, and the three physical health indexes data including the vital capacity/weight ratio, waist-to-hip ratio(WHR) and body mass index(BMI) were analyzed before and after exercise. Results The three physical health indexes have changed significantly(P< 0.01) . The vital capacity/weight ratio, WHR, and BMI were(56.42±1.03) and (61.72±1.09),(0.79±0.05) and (0.77±0.05),and (20.41±1.91) and (19.46±1.87) before and after exercise, respectively. Conclusion The experimental results fully affirmed the effect of the exercise prescription and proved the importance of three physical health indexes in verifying the effectiveness of the exercise prescription, which can provide guidance and empirical reference for physical exercise to female college students. [ABSTRACT FROM AUTHOR]

The article presents a study, which aims to use the pathway sensitivity analysis to detect the pro-proliferation activities of oncogenes and the epidermal growth factor receptor suppressors. Study shows that 12 out of 20 oncoproteins while four out of five tumor suppressors were reported through the use of the analysis approach. It is concluded that the data found through the method has been a useful approach to distinguish pro-proliferation oncoproteins' activities.

Objective To explore the influence factors of myopia of primary and secondary school students, and provide evidence for the preventive measures. Methods The visions of 3493 students of primary and secondary school from Yunnan province were tested with logarithmic visual chart, and the myopic influence factors were investigated with questionnaires. Results Twelve factors showed significant influence on myopia of students, such as sex, grades, nutrition, homework, physical exercise, and parents' myopia and physical exercise (P < 0.05). Conclusion The prevalence of myopia among the primary and secondary school students is affected synthetically by various factors. The school and family should take comprehensive measures to reduce the risk of myopia in students. [ABSTRACT FROM AUTHOR]

The dielectric properties of KCa2Nan-3NbnO3n+1 (n=3–6) Dion–Jacobson homologous series have been investigated. The dielectric constants ([variant_greek_epsilon]) increase with the number of octahedral units (n), and the n=6 compound (KCa2Na3Nb6O19) exhibits a stable dielectric response with [variant_greek_epsilon]=∼500 between 1 kHz and 1 MHz. This n-dependent behavior is similar to those observed in other layered perovskites such as Ruddlesden–Popper and Aurivillius phases. Raman scattering studies reveal that increase in n in KCa2Nan-3NbnO3n+1 leads to higher polarizability of the lattice and softening of the lowest-frequency phonon mode, which is responsible for the observed enhancement in [variant_greek_epsilon] with n. [ABSTRACT FROM AUTHOR]

Control over the emergence of ferroelectric order remains a fundamental challenge for the rational design of artificial materials with novel properties. Here we report a new strategy for artificial design of layered perovskite ferroelectrics by using oxide nanosheets (high-k dielectric Ca2Nb3O10 and insulating Ti0.87O2) as a building block. We approached the preparation of superlattice films by a layer-by-layer assembly involving Langmuir–Blodgett deposition. The artificially fabricated (Ti0.87O2/Ca2Nb3O10)2(Ti0.87O2) superlattices are structurally unique, which is not feasible to create in the bulk form. By such an artificial structuring, we found that (Ti0.87O2/Ca2Nb3O10)2(Ti0.87O2) superlattices possess a new form of interface coupling, which gives rise to ferroelectricity with a good fatigue-free characteristic. Considering the flexibility of self-assembled nanosheet interfaces, this technique provides a route to synthesize a new kind of layered ferroelectric oxides. [ABSTRACT FROM AUTHOR]

Motivation: Small GTPase RhoA regulates cell-cycle progression via several mechanisms. Apart from its actions via ROCK, RhoA has recently been found to activate a scaffold protein MEKK1 known to promote ERK activation. We examined whether RhoA can substantially affect ERK activity via this MEKK1-mediated crosstalk between RhoA and EGFR-ERK pathway. By extending the published EGFR-ERK simulation models represented by ordinary differential equations, we developed a simulation model that includes this crosstalk, which was validated with a number of experimental findings and published simulation results. Results: Our simulation suggested that, via this crosstalk, RhoA elevation substantially prolonged duration of ERK activation at both normal and reduced Ras levels. Our model suggests ERK may be activated in the absence of Ras. When Ras is overexpressed, RhoA elevation significantly prolongs duration of ERK activation but reduces the amount of active ERK partly due to competitive binding between ERK and RhoA to MEKK1. Our results indicated possible roles of RhoA in affecting ERK activities via MEKK1-mediated crosstalk, which seems to be supported by indications from several experimental studies that may also implicate the collective regulation of cell fate and progression of cancer and other diseases. Contact: phacyz@nus.edu.sg Supplementary information: Supplementary data are available at Bioinformatics online. [ABSTRACT FROM AUTHOR]