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Organomineral associations in micro-aggregate architecture are important in soil functions. The effect of greenhouse management on micro-aggregation should be investigated to rationally maximize the benefits of solar greenhouses. The relationships between combined organic matter and inorganic minerals were studied during a long-term greenhouse experiment for 15 years in Shenyang, China. Stepwise settlement method was used to isolate micro-aggregate fractions. Combined organic matter, sesquioxides and combined inorganic phosphorus were also determined. The mass proportions of 50–250 and <1 μm size fractions decreased under long-term greenhouse management. The opposite trends were observed in 10–50 and 1–5 μm size fractions. Significant correlations were also determined between the combined organic matter and amorphous Al oxide, complex Fe and Al oxides, and phosphorus combined with Ca and occluded phosphorus. These results indicated that greenhouse management significantly affected the turnover of organomineral associations in micro-aggregates. [ABSTRACT FROM AUTHOR]

A phytic acid chemical conversion bath was applied to a sample of AZ31 magnesium alloy in this study; a transparent conversion coating formed subsequently on the sample surface. The test results of this coating with a scanning electron microscope (SEM) showed that there exist compact coatings on the surface of treated magnesium alloy. With the analyses of electronic probe microscopy (EPMA) and IR spectrum, a further study of this coating indicated that the coating was mainly composed of phytate and oxide or hydroxid. Furthermore, The electrochemical tests showed that the phytic acid bath conversion treatment enhanced the corrosion resistance of AZ31 magnesium alloys. The optimal pH of the phytic acid bath was 9.00–10.00. [ABSTRACT FROM AUTHOR]

Differential evolution (DE) is a promising evolutionary algorithm for solving optimal reactive power flow problems, but it requires relatively large population to avoid premature convergence. In order to overcome this disadvantage, a novel decomposition and coordination method based on the cooperative co-evolutionary architecture and the voltage-var sensitivity-based power system decomposition technique is proposed and incorporated with DE in this paper. It is implemented with a three-level parallel computing topology on a PC-cluster. Based on the IEEE 118-bus system test case, the effectiveness of the proposed method has been verified by comparison with the parallel basic DE not using the decomposition and coordination technique. [ABSTRACT FROM AUTHOR]

Foreign body ingestion is not an uncommon problem encountered in clinical practice. However, the associated complication of bowel perforation and migration of the foreign body to the liver is rare. We report two cases of hepatic foreign bodies identified intra-operatively as toothpicks, with the alimentary tract being the presumed origin. [ABSTRACT FROM AUTHOR]

Cellular senescence functions as a tumor suppressor that protects against cancer progression. α-Catulin, an α-catenin-related protein, is reported to have tumorigenic potential because it regulates the nuclear factor-κB (NF-κB) pathway, but little is known about its clinical relevance and the mechanism through which it regulates cancer progression. Here, we found that α-catulin mRNA levels were significantly upregulated in cancer cell lines and clinical oral squamous cell carcinomas, which positively correlated with tumor size (P=0.001) and American Joint Committee on Cancer (AJCC) stage (P=0.004). α-Catulin knockdown in the OC2 and A549 cancer cell lines dramatically decreased cell proliferation and contributed to cellular senescence, and inhibited OC2 xenograft growth. Mechanistic dissection showed that α-catulin depletion strongly induced the DNA-damage response (DDR) in both cell lines, via a p53/p21-dependent pathway in A549 cells, but a p53/p21-independent pathway in OC2 cells carrying mutant p53. Global gene expression analysis revealed that α-catulin knockdown altered cell-cycle regulation and DDR pathways at the presenescent stage as well as significantly downregulate several crucial genes related to mitotic chromosome condensation, DDR and DNA repair systems, which suggests that its depletion-induced cellular senescence might be caused by chromosome condensation failures, severe DNA damage and impaired DNA repair ability. Our study provides evidence that α-catulin promotes tumor growth by preventing cellular senescence and suggests that downregulating α-catulin may be a promising therapeutic approach for cancer treatment. [ABSTRACT FROM AUTHOR]

The natural reservoir for influenza viruses is waterfowl, and from there they succeeded in crossing the barrier to different mammalian species. We analyzed the adaptation of avian influenza viruses to a mammalian host by passaging an H9N2 strain three times in differentiated swine airway epithelial cells. Using precisioncut slices from the porcine lung to passage the parental virus, isolates from each of the three passages (P1 to P3) were characterized by assessing growth curves and ciliostatic effects. The only difference noted was an increased growth kinetics of the P3 virus. Sequence analysis revealed four mutations: one each in the PB2 and NS1 proteins and two in the HA protein. The HA mutations, A190V and T212I, were characterized by generating recombinant viruses containing either one or both amino acid exchanges. Whereas the parental virus recognized α2,3-linked sialic acids preferentially, the HA190 mutant bound to a broad spectrum of glycans with α2,6/8/9-linked sialic acids. The HA212 mutant alone differed only slightly from the parental virus; however, the combination of both mutations (HA190+HA212) increased the binding affinity to those glycans recognized by the HA190 mutant. Remarkably, only the HA double mutant showed a significantly increased pathogenicity in mice. In contrast, none of those mutations affected the ciliary activity of the epithelial cells which is characteristic for virulent swine influenza viruses. Taken together, our results indicate that shifts in the HA receptor affinity are just an early adaptation step of avian H9N2 strains; further mutational changes may be required to become virulent for pigs. [ABSTRACT FROM AUTHOR]

The method of mode matching (MM) is used to construct ideal waveports in the context of the method of moments (MoM). The waveports can provide not only excitations as sources but also perfectly matched loads for traveling-wave slotted waveguide antennas. Additionally, the application of the higher order basis functions (HOBs) in MoM significantly reduces the number of unknowns compared to the RWG basis functions. Numerical results show that the proposed method is accurate and efficient for traveling-wave slotted waveguide antennas. Finally, a Ka-band waveguide array with 1976 narrow-wall slots is solved using a high-performance cluster. [ABSTRACT FROM PUBLISHER]

We synthesized a series of cobalt-iron Prussian blue analogues in the form of nanocubes with which we tuned the amount of Cesium cation in the tetrahedral sites of the structure and varied nature of the alkali cation in the compound adopting a single microemulsion technique. Structure and morphology of the compound had been investigated by combining energy-dispersive X-ray spectroscopy (EDS), inductively coupled plasma (ICP), thermo-gravimetry analysis (TGA), infrared spectroscopy (IR), powder X-ray diffraction (XRD) and Transmission electron microscopy experiments (TEM). To directly determine the coercivity, remanence and Curie temperature, superconducting quantum interference device magnetometer (SQUID) was performed. Our investigation suggests that the amount and nature of the alkali cation are critical parameters for understanding the magnetic properties of the nanoparticles. [ABSTRACT FROM AUTHOR]