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This paper addresses theoretically and methodologically the electrical characteristics (including node voltage and equivalent resistance) of a class of n-ladder resistor networks with external load. The authors establish, with node voltage as a variable, the second-order difference equation model and boundary condition equation model based on Kirchhoff’s law. They propose the general and specific methods of solution for different equations and at once obtain the voltage formula of any node in the n-ladder network with external load and the equivalent resistance formula between any two nodes as well. Special cases in the conclusion section are analyzed and discussed. In particular, they find the oscillation and resonance characteristics of the LC network under different conditions by carrying out an analysis and research into the equivalent complex impedance characteristics of the LC network.

Complex n-order complex impedance network is a kind of common complex problems. The electrical characteristics of its equivalent complex impedance are usually complex. We consider a kind of complex impedance network model of two terminal ladder network with complex parameters, and investigate the characteristics of equivalent complex impedance by deriving the analytical formula of equivalent complex impedance. The main research methods are as follows: firstly, the equivalent model is constructed. Secondly, the nonlinear difference equation model is established according to the equivalent model, and then the universal law of the equivalent complex impedance of n-ladder network is given by studying the solution of the nonlinear difference equation. Finally, the specific cases of LC network and non-ideal transmission line are studied respectively, and compared with the relevant results.

This paper introduces an n-order network model with Y circuits to investigate the electrical properties, and it is an entirely new question that has seldom been addressed in the academic world. We carry out the research by means of building an equivalent model. Firstly, we use Kirchhoff's law to build a second-order nonlinear recurrence equation model. Secondly, by using variable substitution we transform the nonlinear equation into a linear difference equation. Thirdly, we name the process recurrence transformation of n-order network, called N-RT for short. Based on the linear difference equation, an analytical solution is offered to the problem of the equivalent resistance of the n-order network with Y circuits. This research is going to find specific application in many cases. What's important, this paper further investigates the equivalent complex impedance of LC network and the electrical properties of complex impedance, and illustrates the oscillation and resonance characteristics of LC network with 3D graphs.

This paper investigates the electrical properties of a class of n-order triangular resistor network model. The authors establish, by constructing equivalent model, the second-order nonlinear difference equation model. We propose, by using equivalent transformation method, the general and specific methods of solution for the nonlinear difference equation and at once obtain an accurate equivalent resistance formula of n-order triangular resistor network, and a series of special conclusions are analyzed and compared. Finally, we study the oscillation and resonance characteristics of the triangular LC network under different conditions, where the method used is variable substitution by using the equivalent resistance results obtained. This study reveals the electrical characteristics of triangular LC network and establishes a new theoretical foundation for related disciplines.

The main purpose of this study was to characterize the adsorption behavior of naphthalene, one of polycyclic aromatic hydrocarbons (PAHs), on silk fabric. Typical batch reactors were used to perform adsorption kinetics and isotherm experiments. It was found in this study that the pseudo-second-order model described the sorption kinetics data well. An adsorption isotherm in the form of Linear Equation was observed, and the adsorbed capacity was influenced evidently by the enhanced temperature. In addition, the results demonstrated that silk fabric could adsorb large amounts of naphthalene from water, and the maximum exceeded 700 μg/g.

Some flashover incidents of high-voltage transmission lines are reported to be induced by fire. Though the mechanism of fire induced flashover is not well understood, it is deemed that fire could reduce the insulation strength of air. This paper has compared the breakdown characteristics of gaps in normal air conditions and those in fire. The results show that the breakdown voltage or electric field strength of gaps in fire decreases greatly. The value of breakdown electric field strength in alcohol flame is about 1.454 KV/cm, which is only about 28.8% of that in air. The value of breakdown electric field strength in wood crib fire is about 0.300KV/cm, corresponding to 19.9% of that in air. This study demonstrates that flame and soot particle of fire are responsible for fire induce flashover of high-voltage transmission lines.

Cyclin D1 plays a pivotal role in cell-cycle transition through G1 phase. In this article, we found that Degenerative Spermatocyte Homolog 1 (DEGS1) up-regulated the expression of cyclin D1 and the activation of transcription factor NF-κB was essential for DEGS1-induced cyclin D1 production. Forced expression of DEGS1 in Esophageal carcinoma cell line Eca109 cells increased their ability of cell migration and significantly induced tumor metastasis in nude mice, whereas RNA interference-mediated knockdown of DEGS1 cells significantly inhibited cell migration in vitro, as well as tumor metastasis in vivo. Our results demonstrated that expression of DEGS1 up-regulated the expression of cyclin D1 and enhanced the efficiency of tumor metastasis. © 2009 Wiley-Liss, Inc.

This study sought to investigate the effect of delayed pulsed-wave ultrasound with low frequency on drug release from and the antimicrobial efficacy of vancomycin-loaded acrylic bone cement in vivo and the possible mechanism of this effect. After the implantation of cement and the inoculation of Staphylococcus aureus into the bilateral hips of rabbits, ultrasound (average intensity, 300 mW/cm 2 ; frequency, 46.5 kHz; on/off ratio, 20 min/10 min) was applied to animals in the normal ultrasound group (UG 0-12 ) from 0 through 12 h after surgery and to those in the delayed-ultrasound group (UG 12-24 ) from 12 through 24 h after surgery. The control group (CG) was not exposed to ultrasound. Based on vancomycin concentrations in left hip cavities at projected time intervals, the amount of time during which the local drug concentration exceeded the MIC ( T >MIC ) in UG 12-24 was significantly prolonged compared with that in either CG or UG 0-12 , and the ratios between the areas under the concentration-time curves over 24 h and the MIC for UG 0-12 and UG 12-24 were both increased compared with that for CG. The greatest reductions in bacterial densities in both right hip aspirates and right femoral tissues at 48 h were achieved with UG 12-24 . Local hemorrhage in rabbits of UG 0-12 during the 12-h insonation was more severe than that in rabbits of UG 12-24 . Of four variables, the T >MIC and the bioacoustic effect were both identified as parameters predictive of the enhancement of the antimicrobial efficacy of cement by ultrasound. Sustained concentrations above the MIC replaced early high maximum concentrations and long-term subtherapeutic release of the drug, provided that ultrasound was not applied until local hemorrhage was relieved. The enhancement of the antimicrobial efficacy of cement by ultrasound may be attributed to the prolonged T >MIC and the bioacoustic effect caused by ultrasound.

In the centrosymmetric title compound, 2C4H12NO+·C8H4O42−, two N,N-diethyl(hydroxy)ammonium cations are linked to a benzene-1,4-dicarboxylate dianion by a combination of O—H...O and N—H...O hydrogen bonds, which can be described in graph-set terminology as R22(7). The crystal structure is further stabilized by C—H...O hydrogen bonds, leading to the fomation of a ribbon-like network.

JARID1B (jumonji AT rich interactive domain 1B) is a large nuclear protein that is highly expressed in breast cancers and is proposed to function as a repressor of gene expression. In this paper, a phage display screen using the N-terminus of JARID1B as bait identified one of the JARID1B interacting proteins, namely PcG protein (Polycomb group) hPc2. We demonstrated that the C-terminal region, including the COOH box, was required for the interaction with the N-terminus of JARID1B. In a reporter assay system, co-expression of JARID1B with hPc2 significantly enhanced the transcriptional repression. These results support a role for hPc2 acting as a transcriptional co-repressor.

Objective: The aims of this research were to purify and identify the 130 kDa (CagA) protein ofH. pylori clinical isolate HP97002 and evaluate the relationships between the purified 130 kDa (CagA) protein and gastric diseases. Methods: The procedure for isolating the protein included 6 mol/L guanidine extract, size exclusion chromatography and elusion from gel. Sera of 68 patients with gastric diseases (44 with chronic gastritis, 15 with atrophic gastritis, 7 with peptic ulcer disease, 2 with gastric cancer) were obtained, and the serological response to CagA was studied by Western-blot using the purified protein. Results: The purified protein was 130 kDa and preserved good antigenicity and revealed basic isoelectric point about of 8.1. Among 68 sera, 43 sera could recognize the purified protein associated with chronic gastritis 47.7% (21/44), atrophic gastritis 86.7% (13/15), peptic ulcer disease 100% (7/7), gastric cancer 100% (2/2). Compared with each other, the difference was significant (χ2=13.327,P=0.004), and 130 kDa (CagA) protein was associated with severe gastric diseases (r s=0.442,P=0.001). Conclusion: The 130 kDa (CagA) protein was associated with severe gastric diseases.

In the title compound, C11H14N4O4, doxofylline [7-(1,3-di­oxolan-2-ylmeth­yl)-3,7-dihydro-1,3-dimethyl-1H-purine-2,6-dione] mol­ecules are linked by C—H⋯N hydrogen bonds to form weakly hydrogen-bonded dimers, which are further linked by C—H⋯O hydrogen bonds to form a three-dimensional network.

In the title molecular compound, C4H12NO+·C8H5O4−, the N,N-diethyl(hydroxy)ammonium cation (DTHA) is linked to the 3-carboxybenzoate anion (HBDL) by O—H...O and N—H...O hydrogen bonds with a graph-set motif R22(7). In the crystal, helical chains are formed by O—H...O hydrogen bonds, propagating along [010]. The crystal structure is further stabilized by π–π interactions between inversion-related HBDL benzene rings [centroid–centroid distance = 3.900 (4) Å] and C—H...O interactions.