Healing Pattern Analysis for Dental Implants Using the Mechano-Regulatory Tissue Differentiation Model

(1) Background: Our aim is to reveal the influence of the geometry designs on biophysical stimuli and healing patterns. The design guidelines for dental implants can then be provided. (2) Methods: A two-dimensional axisymmetric finite element model was developed based on mechano-regulatory algorithm. The history of tissue differentiation around eight selected implants can be predicted. The performance of the implants was evaluated by bone area (BA), bone-implant contact (BIC); (3) Results: The predicted healing patterns have very good agreement with the experimental observation. Many features observed in literature, such as soft tissues covering on the bone-implant interface; crestal bone loss; the location of bone resorption bumps, were reproduced by the model and explained by analyzing the solid and fluid biophysical stimuli and (4) Conclusions: The results suggested the suitable depth, the steeper slope of the upper flanks, and flat roots of healing chambers can improve the bone ingrowth and osseointegration. The mechanism related to solid and fluid biophysical stimuli were revealed. In addition, the model developed here is efficient, accurate and ready to extend to any geometry of dental implants. It has potential to be used as a clinical application for instant prediction/evaluation of the performance of dental implants.     

Physical study of room‐temperature‐cured epoxy/thermally reduced graphene oxides with various contents of oxygen‐containing groups

In this study, the effects of different oxygen‐containing group contents in thermally reduced graphene oxides (TRGs) for enhancing the physical properties of epoxy nancomposites was examined. The epoxy/TRG nanocomposites (ETNs) were prepared by a room temperature curing method in the presence of TRGs containing different oxygen‐containing groups and were then characterized by Fourier transform infrared spectroscopy. TRG contents with higher oxygen‐containing group contents (ca 33%) were found to show better dispersion capability in the epoxy matrix than TRGs with lower oxygen‐containing group contents (ca 11%) based on morphological observations by transmission electron microscopy. The better dispersion capability of TRGs with higher oxygen‐containing group contents in ETN membranes was found to lead to significantly enhanced mechanical strength, thermal stability and thermal conductivity based on measurements of dynamic mechanical analysis, tensile tests, thermogravimetric analysis and by the transient plane source technique. © 2014 The Authors. Polymer International published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry     

浅谈智能化小区安全防范设计

随着智能化小区的不断涌现,居民安全已成为智能化小区建设中极为重要的问题.文章就智能化小区的安全防范设计进行探讨,简要介绍了周界报警、闭路电视监控、电子巡更、访客对讲、住户防盗与安全报警等系统的设计.     

A New Test to Evaluate the Fire Performance of Residential Sprinklers

Fire tests were conducted using the Underwriters Laboratories (UL) UL 1626 Fire Test for residential sprinklers. The results indicated that sprinkler performance in UL 1626 could not be reproduced due to differences in material flammability properties. This conclusion was reached in a cooperative effort with UL. Factory Mutual Research's Approval fire test that had been redesigned based on UL 1626 was thus subject to the same variability. A new fire test was developed using fuel with controlled material flammability parameters based upon the use of the ASTM E2058 Fire Propagation Apparatus. The new fuel package consists of a wood crib (one half the height of the one which was used in UL 1626) supported over a pan with heptane, two polyether foam cushions (about 60% greater in density than the foam previously used in UL 1626) measuring 34 in by 30 in by 3 in (864 mm by 762 mm by 76 mm) and in (6 mm) Douglas Fir plywood paneling. The new fire test was shown in a series of sprinklered fire tests to provide a reproducible challenge to residential sprinklers comparable to that observed in the Factory Mutual Research and the Los Angeles Residential Test Programs.     

Effect of temperature on removal of heavy metals from contaminated river sediments via bioleaching

The aim of this study was to determine the effect of temperature on the solubilization of heavy metals from contaminated river sediment by sulfur oxidizing bacteria taken from Ell-Ren River sediment. Of three temperatures tested (25 degrees C, 37 degrees C and 55 degrees C), pH decrease was greatest at 37 degrees C, indicating that, after acclimation, bacterial oxidizing activity is greatest at this temperature. At 55 degrees C, pH change was similar to that which occurred with no inoculum added. The increase in sulfates and high pH at 55 degrees C indicate that the indirect mechanism was not initiated at this temperature. Solubilization efficiency of total extractable Ni, Zn, Cu and Cr was high (>90%) at 37 degrees C, whilst that of Pb was only 60.4%. Except for Pb, the optimal temperature for solubilization of total extractable heavy metal was 37 degrees C. The order of average solubilization efficiency of total extractable heavy metals was Ni, Zn, Cu>Cr>Co, Pb. The solubilization efficiency of Pb and Co was markedly less than that of other heavy metals. Transfer of heavy metals between binding fractions was most apparent at 55 degrees C before and after bioleaching.     

The Effects of Annealing Atmosphere on the Electrical Properties of MgNb2O6/ITO Heterostructures

The effects of annealing atmosphere (N₂, air and O₂) on the electrical properties of sol–gel‐derived MgNb₂O₆/ITO heterostructures are discussed in this work. All samples exhibited the amorphous phase and were highly transparent. The percentage of Nb⁴⁺ content increased when the films were annealed in the oxygen‐deficient conditions, which could lead to semiconducting films. In addition, the results show that the electrical properties of sol–gel‐derived MgNb₂O₆ thin films could be tuned based on the annealing atmosphere. Moreover, the conduction mechanisms of MgNb₂O₆/ITO heterostructures are also discussed in this study. The results show that MgNb₂O₆ thin films have potential for use in multifunctional optoelectronic applications, due to their flexible electrical properties and good transparency.     

Optimization of an RFID location identification scheme based on the neural network

An indoor localization technology is increasingly critical as location‐aware applications evolve. Researchers have proposed several indoor localization technologies. Because most of the proposed indoor localization technologies simply involve using the received signal strength indicator value of radio‐frequency identification (RFID) for indoor localization, radio‐frequency interference, and environmental factors often limit the accuracy of localization results. Therefore, this study proposes an accurate RFID localization based on the neural network (ARL‐N²), a passive RFID indoor localization scheme for identifying tag positions in a room, combining a location identification based on dynamic active RFID calibration algorithm with a backpropagation neural network (BPN). The proposed scheme composed of two phases: in the training phase, an appropriate BPN architecture is constructed using the training data derived from the coordinates of reference tags and the coordinates obtained using the localization algorithm. By contrast, the online phase involves calculating the tracking tag coordinates and using these values as BPN inputs, thereby enhancing the estimated location. A performance evaluation of the ARL‐N² schemes confirms its high localization accuracy. The proposed method can be used to locate critical objects in difficult‐to‐find areas by creating minimal errors and applying and economical technique. Copyright © 2013 John Wiley & Sons, Ltd.