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To study the prevalence of Parvimonas micra (Pm) and the associations between Pm and pulp dominant pathogens in order to reflect the colonization of Pm in the infected root canals with chronic periradicular periodontitis.A total of 120 teeth diagnosed as chronic periradicular periodontitis from 104 patients were included into the study. The teeth were allocated into untreated (primary infectious) and root-canal- treated (secondary infectious) groups with 60 in either group. Samples were collected from the root canals using sterile files and paper points, and subsequent extraction of bacterial DNA was undertaken. The Pm 16S rDNA level was evaluated using 16S rDNA PCR. The prevalence of Pm in chronic periradicular periodontitis was determined accordingly. Then, the associations of Pm and Enterococcus faecalis (Ef), Porphyromonas endodontalis (Pe) as well as Porphyromonas gingivalis (Pg) were analysed.Pm was detected in 40% (24/60) of the samples from the primary infectious group, 5% (3/60) from the secondary infectious group. The prevalences of Pm from the two groups were different significantly (χ² = 21.06, P0.05). Significant correlations (untreated group OR = 5.98, root-canal-treated group OR = 33.50) between Pm and Pe were identified in both groups, while the correlations between Pm and Pg as well as Ef were not of significance, respectively.A significantly higher relevance ratio of Pm was estimated in the primary infectious group than the secondary infectious one. Pm and Pe were correlated significantly in the infected root canals, suggesting a symbiotic relation between these two bacteria.

One-dimensional (1D) Mn₃O₄ nanorod/Zn2SnO4 nanoneedle hierarchical composites were conveniently synthesized via a simple hydrothermal process at 180 °C for 24 h. It was found that the reaction time and an appropriate amount of ammonia play vital roles during their formation process, and their formation is likely driven by the lattice match of the cubic Zn₂SnO₄ nanoneedles and cubic Mn₃O₄ nanorods. The as-obtained composites deliver a high initial discharge capacity of 1370.9 mA h g(-1) at 100 mA g(-1) in the range of 0.01-3.0 V, and a reversible specific capacity of 577.4 mA h g(-1) could be retained after 50 cycles. It is noteworthy that 441.5 mA h g(-1) could be maintained after 50 cycles even if the current density was set as high as 1000 mA h g(-1), and the rate performance of nanocomposites (200, 500, 1000 mA g(-1)) also shows excellent reversible character. The high specific capacity, good cycling stability and high rate performance of the as-obtained composites enable them to be promising and competitive high-performance anodes in lithium-ion batteries (LIBs). It is worth noting that the fabrication method reported here can be easily extended to prepare other 1D metal oxide hybrid materials including Mn₃O₄/ZnFe₂O₄, Mn₂O₃/CoFe₂O₄ and Mn₂O₃/NiFe₂O₄ composites via a similar hydrothermal process with/without subsequent calcination, which hold great promise for their wide potential applications in energy, catalysis and environmental science and technology.

This paper presents an optimal unified combination rule within the framework of the Dempster-Shafer theory of evidence to combine multiple bodies of evidence. It is optimal in the sense that the resulting combined m-function has the least dissimilarity with the individual m-functions and therefore represents the greatest amount of information similar to that represented by the original m-functions. Examples are provided to illustrate the proposed combination rule.

The modified Pechini method using ethylenediaminetetraacetic acid as a chelating agent to prepare Ba2Ti9O20is reported. The resin precursors were prepared and heated at 700 to 1200 °C in air, and x-ray diffraction was used to determine the phase transformations as a function of temperature. Single-phase Ba2Ti9O20was obtained at 1200 °C for 2–6 h, without the need of prolonged heat treatment time. The process was simple and easy to control: low-temperature conditions or a protective atmosphere was not needed. Differential thermal analysis, thermogravimetric analysis, and Raman spectroscopy were used to characterize the precursors and derived oxide powders. Details of the synthesis and characterization of the resultant products were given.

The objective function of the original (fuzzy) c-mean method is modified by a regularizing functional in the form of total variation (TV) with regard to gradient sparsity, and a regularization parameter is used to balance clustering and smoothing. An alternating direction method of multipliers in conjunction with the fast discrete cosine transform is used to solve the TV-regularized optimization problem. The new algorithm is tested on both synthetic and real data, and is demonstrated to be effective and robust in treating images with noise and missing data (incomplete data).

Electric field tunable ferroelectric materials have attracted extensive attention in recent years due to their potential applications for tunable microwave device such as tunable filters, phased array antennas, delay lines and phase shifters (Maiti et al. 2007a; Rao et al. 1999; Romanofsky et al. 2000; Varadan et al 1992.; Zhi et al. 2002). Ba1-xSrxTiO3 and BaZrxTi1−xO3 have received the most attention due to their intrinsic high dielectric tunability. However, the high inherent materials loss and high dielectric constant has restricted its application in tunable microwave device. Various methods have been investigated to lower the dielectric constant and loss tangent of pure ferroelectrics. Forming ferroelectric-dielectric composite is an efficient method to reduce material dielectric constant, loss tangent and maintain tunability at a sufficiently high level. For binary ferroelectric-dielectric composite (such as BST+MgO) (Chang & Sengupta 2002; Sengupta & Sengupta 1999), with the increase of dielectrics content, the dielectric constant and tunability of composites decrease. In order to decrease the dielectric constant of binary composite, it is necessary to increase the content of linear dielectric, and the tunability will decrease inevitably due to ferroelectric dilution. Replacing one dielectric by the combination of dielectrics with different dielectric constants and forming ternary ferroelectric-dielectric composite can decrease the dielectric constant of composite and maintain or even increase the tunability. This is beneficial for tunable application. The Ba0.6Sr0.4TiO3-Mg2SiO4-MgO and BaZr0.2Ti0.8O3-Mg2SiO4-MgO composites exhibited relatively high tunability in combination with reduced dielectric permittivity and reduced loss tangent (He et al. 2010, 2011). With the increase of Mg2SiO4 content and the decrease of MgO content in Ba0.6Sr0.4TiO3-Mg2SiO4-MgO composite, the dielectric constant decrease and the tunability remain almost unchanged. For BaZr0.2Ti0.8O3-Mg2SiO4-MgO composite, an anomalous relation between dielectric constant and tunability was observed: with the increase of Mg2SiO4 content (>30 wt%), the dielectric constant of composite decreases and the tunability increases. The anomalous increased tunability can be attributed to redistribution of the electric field. Ba1-xSrxTiO3-Mg2TiO4-MgO can also form ferroelectric (Ba1-xSrxTiO3)-dielectric (Mg2TiO4-MgO) ternary composite and the dielectric constant can be decreased. With the increase of Mg2TiO4 content and the decrease of MgO content, the tunability of Ba1-xSrxTiO3Mg2TiO4-MgO composite increase. The multiple-phase composites might complicate method to effectively deposit films, particularly if the dielectrics and ferroelectric are not compatible for simultaneous deposition or simultaneous adhesion with a substrate or with

The paper presents an approach based on Dempster-Shafer theory of evidence to quantify uncertainty in flight plan trajectories. The approach is developed for 4D aircraft trajectories. However, as the full data set (latitude, longitude, altitude vs. time) for flight plan trajectories is not publicly available, only uncertainty in the horizontal projection (longitude vs. latitude) of the trajectories is considered in the present paper. Two flight phases - climb and descent - are chosen to demonstrate the proposed approach. The actual dataset for two flights -- Delta DAL1212 from Los Angeles to Atlanta and Airtran Airways TRS841 from Atlanta to Orlando -- are chosen to represent a cross-country flight and a southeastern flight through Florida from the busy airport hub, Atlanta Hartsfield-Jackson International, is used.

Ba(0.6)Sr(0.4)TiO(3)-Mg(2)SiO(4)-MgO composite ceramics were prepared by a solid-state reaction method and their dielectric tunable characteristics were investigated for the potential application as microwave tunable materials. The addition of Mg(2)SiO(4)-MgO into Ba(0.6)Sr(0.4)TiO(3) forms ferroelectric (Ba(0.6)Sr(0.4)TiO(3))-dielectric (Mg(2)SiO(4)-MgO) composites and shifts the Curie temperature to a lower temperature. The dielectric constant and loss tangent of Ba(0.6)Sr(0.4)TiO(3)-Mg(2)Si(O4)- MgO composites have been decreased and the overall tunability is maintained at a sufficiently high level. The microwave dielectric properties of Ba(0.6)Sr(0.4)TiO(3)-Mg(2)Si(O4)-MgO composites were evaluated. Ba(0.6)Sr(0.4)TiO(3)-Mg(2)SiO(4)-MgO composites have tunability of 9.2 to 10.5% at 100 kHz under 2 kV/mm, indicating that it is a promising candidate material for tunable microwave applications requiring a low dielectric constant.

The paper presents an approach based on Dempster-Shafer theory of evidence to represent uncertainty in flight plan departure and arrival times. It is shown that the accuracy and credibility of flights plans for a given flight can be completely represented by belief functions. A procedure on how to construct belief functions using the data of actual and scheduled (estimated) departure and arrival times is described. Application of the approach is demonstrated using actual flight data for two flights: Delta DAL1212 from Los Angeles to Atlanta and Airtran Airways TRS841 from Atlanta to Orlando, chosen to represent a cross-country flight and a southeastern flight through Florida from a busy hub airport, Atlanta Harsfield-Jackson Intl.

Laser ablation biologic tissue is an important performance of laser application. Based on the combination function of two-wavelength laser to biologic tissue ablation, the semi-continuous two-wavelength laser at 532nm and 1064nm ablating blood tissue was investigated by experiment. The fresh pork and pig liver specimens were ablated at different laser power density and different laser power proportion in water conditions and ablation depth and thermo-damage thickness were measured. The experiment results indicate that there is no effective ablation but deeper thermo-damage of the 1064 nm laser to biologic tissue in water conditions when the 532nm laser power is little but the ablation efficiency sharp inc- reases and the thermo-damage sharp decreases when the 532nm laser power arrives to a threshold. The combination function of two wavelength laser to tissue ablation is appeared here. It indicates that the ablation efficiency and hemostatic function in laser surgery can be adjusted by the two-wavelength laser power proportion.

The use of phase-change materials for latent heat storage is a new type of environmentally-friendly energy-saving technologies. Molten salts, one kind of phase-change materials, which have high latent heats, and whose phase transition temperatures match the high temperatures of heat engines, are the most widely used high-temperature phase-change heat storage materials. However, the heat transfer at solid/liquid phase interface belongs to Micro/Nanoscale Heat transfer, lots of the thermal properties of molten salt at melting point is difficult to test. In this investigation, based on the theory that the thermal conductivity can be determined by measuring the speed of the propagation of the solid/liquid phase interface during phase change, a set of system is developed to investigate the thermal conductivity of molten salts at liquid/solid phase transformation point. Meanwhile, mathematical calculation is applied to intuitively simulate the melting and solidifying process in the phase change chamber, by which the error could be analyzed and partly corrected and the result precision could also be increased. And a series of verification experiments have been performed to estimate the precision and the applicability of the measuring system to evaluate the feasibility of the method and measuring system. This research will pave the way to the follow-on research on heat storage at high temperature in industry.Copyright © 2009 by ASME

Fractional laser resurfacing technology is one of those medical advanced technologies. It has bridged the gap between ablative lasers and non-ablative lasers. Fractional laser resurfacing is a new laser skin treatment modality that creates numerous microscopic thermal injury zones with controlled width, depth and density. Those injury zones are surrounded by a reservoir of spared epidermal and dermal tissue that allow for rapid repair of laser-induced thermal injury. In this paper the ideal laser parameters, the damage depth and width, the relationship between the energy and the damage about fractional resurfacing and so on are analyzed. The results show: the Q-switch Er:YAG laser is an ideal lasers for fractional laser resurfacing, the dynamical equilibrium time of fractional resurfacing treating is depended on the energy, the damage area is only the evaporation zone with minimal residual heat, and the damage width and depth of the injury zone in fractional treating can be controlled precisely by the appropriate adjustment of the diameter, energy, pulse width and frequency of Er:YAG laser beam.

Potassium-titanyl-phosphate (KTP) green (frequency double Nd:YAG) laser vaporizationwas a safe and effective procedure in urology. This study demonstrated the potential and feasibility of the domestically manufactured green laser to treat patients with Benign Prostate Hyperplasia (BPH). The porcine muscles were vaporized with different power (7.5-57W) under water by the domestically manufactured KTP laser system. The fresh canine prostate tissues were also vaporized with 43W green laser. All biology tissues were weighed, measured, serially sectioned, and whole mounted for histologic analysis. The laser vaporization in human prostate tissue was performed clinically. The porcine muscles were vaporized under water for ten seconds. Increasing laser power appeared to increase depth and diameter of vaporization while maintaining or decreasing depth of necrosis. With domestically manufactured 60W KTP laser system, the laser prostatectomy was performed in 15 BPHs. All patients received spinal anesthesia. Isotonic saline at room temperature was used as irrigation solution. Postoperative insertion of an indwelling catheter was mandatory. The initial study of the domestically manufactured KTP laser vaporization in animal tissue and human prostate tissue confirms its technical feasibility in most cases and good intraoperative and early postoperative effect.

Laser technology has succeeded in medical application. High power 532nm laser has applied in prostate ablation and other clinic application. To understand optical property of bio-tissue at 532nm wavelength, a method of monitoring surface temperature was used to measure absorption coefficient of gall-stone, porcine liver and canine prostate. The absorption coefficient of gall-stone is about 62cm-1 at 532nm wavelength, and those of porcine liver and canine prostate are about 13cm-1 and 5.4cm-1, respectively. These results help to understand the optical property of bio-tissue and offer theoretic reference for optical dosimetry in clinic application.© (2007) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.