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1.
Periodontitis is a multifactorial disease. The aim of this explorative study was to investigate the role of Interleukin-(IL)-1, IL-4, GATA-3 and Cyclooxygenase-(COX)-2 polymorphisms after non-surgical periodontal therapy with adjunctive systemic antibiotics (amoxicillin/metronidazole) and subsequent maintenance in a Caucasian population. Analyses were performed using blood samples from periodontitis patients of a multi-center trial (ClinicalTrials.gov NCT00707369=ABPARO-study). Polymorphisms were analyzed using quantitative real-time PCR. Clinical attachment levels (CAL), percentage of sites showing further attachment loss (PSAL) ≥1.3 mm, bleeding on probing (BOP) and plaque score were assessed. Exploratory statistical analysis was performed. A total of 209 samples were genotyped. Patients carrying heterozygous genotypes and single-nucleotide-polymorphisms (SNP) on the GATA-3-IVS4 +1468 gene locus showed less CAL loss than patients carrying wild type. Heterozygous genotypes and SNPs on the IL-1A-889, IL-1B +3954, IL-4-34, IL-4-590, GATA-3-IVS4 +1468 and COX-2-1195 gene loci did not influence CAL. In multivariate analysis, CAL was lower in patients carrying GATA-3 heterozygous genotypes and SNPs than those carrying wild-types. For the first time, effects of different genotypes were analyzed in periodontitis progression after periodontal therapy and during supportive treatment using systemic antibiotics demonstrating a slight association of GATA-3 gene locus with CAL. This result suggests that GATA-3 genotypes are a contributory but non-essential risk factor for periodontal disease progression.  相似文献   
2.

Although Long-term Evolution (LTE) technology has currently being used in data and voice transmission, reserved frequency bands for GSM is still in use due to its strengthen against multipath fading and it provides wider coverage area. Poor coverage problems caused by low signal level directly reduce network performance and cause undesirable cases for voice transmission. The aim of this study is first to solve handover (HO) problems due to the low signal quality and bad speech quality by hardware configuration and changing optimization parameters in detail as a novelty. The second is to examine the KPI values of the test region where HO problems have been solved and to determine whether the network contributed to the network quality. Offered method has made the network having following improvements; the value of RxQual drops from 0.61 to 0.57, number of failure in random access channel (RACH) drops down from 12 to 2, the number of failure in SDCCH drops down from 6 to 2, the total number of blocked calls from 18 to 4, and the number of dropped calls drops down to 2 from 5. Another criterion of the network quality the average for both uplink and downlink mean opinion score (MOS) value of region increased from 3.51 to 3.86. Also CSSR has been increased from 94.43 to 97.82% and HO success rate has been reached from 93.56 to 99.13%.

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3.
In many wireless sensor network (WSN) applications, the location of a sensor node is crucial for determining where the event or situation of interest occurred. Therefore, localization is one of the critical challenges in WSNs. Mobile anchor node assisted localization (MANAL) is one of the promising solutions for the localization of statically deployed sensors. The main problem in MANAL localization is that the path planning of the mobile anchor (MA) node should be done so that the localization error in the network will be minimal and that all unknown nodes in the network are covered. This paper proposes a new path planning approach called nested hexagons curves (NHexCurves) for MANAL. NHexCurves guarantees that it will receive messages from at least three non-collinear anchors to locate all unknown nodes in the network. The proposed model has compared six different path planning schemes in the literature using weighted centroid localization (WCL). In these comparisons, first of all, localization errors of the models are compared using some statistical concepts. Second, the variation of the localization error according to parameters such as resolution (R) and the standard deviation of noise (σ) is observed. Then, with similar approaches, the standard deviation of errors, localization ratio, scalability performances, and finally, path lengths of the models are examined. The simulation results show that the NHexCurves static path planning model proposed in this study stands out compared to other models with high localization error and localization ratio performance, especially at low resolutions, due to its path design. At the same time, the lowest error values according to σ are obtained with the proposed model among all models considered.  相似文献   
4.
An interpretation for the use of cumulants in narrowband array processing problems is proposed. It is shown how fourth-order cumulants of multichannel observations increase the directional information compared with second-order statistics. Based on the interpretation, it is shown how cumulants can be used to increase the effective aperture of an arbitrary antenna array. The amount of partial information necessary to jointly calibrate an arbitrary array and estimate the directions of far-field sources is also investigated. It is proven that the presence of a doublet and use of fourth-order cumulants is sufficient to accomplish this task. The proposed approach is computationally efficient and more general than covariance-based algorithms that have addressed the calibration problem under constraints. A class of beamforming techniques is proposed to recover the source waveforms. Proposed estimation procedures are based on cumulants, which bring insensitivity to the spatial correlation structure of additive Gaussian measurement noise. Simulations are provided to illustrate the use of the proposed algorithms  相似文献   
5.
Improvement of superconducting properties, such as critical current density J/sub c/ and trapped magnetic field, of melt textured YBa/sub 2/Cu/sub 3/O/sub 7-x/ (Y123) require introducing of effective pinning sites, e.g., nonsuperconducting inclusions, twin boundaries and other defects. It has been shown that addition of small quantities of BaCeO/sub 3/ (<0.5 wt%) into Y123 results in an increase of the J/sub c/. However, higher cerium concentrations affect the solidification process and inhibit the growth of melt textured Y123 single crystals. In this study, the effect of BaCeO/sub 3/ additions on the growth and microstructural development of melt textured Y123 single crystals were investigated. The relationship between the solidification kinetics, microstructural development and superconducting properties of Y123 melt textured single crystals with cerium additives is discussed.  相似文献   
6.
In the dry milling of wheat flour, each unit process (roller mill, purifier, sifter, etc.) produces a mixture with varying amounts of wheat endosperm and non-endosperm byproducts. Chemical images with 82 000 pixels of each intermediate product stream issuing from an individual processing machine are readily analyzed in terms of the relative amount of endosperm and non-endosperm. Approximately three minutes is required to produce an image of each intermediate product stream. Applying partial least squares (PLS) chemometric software to identify individual pixels, which enables calculation of the relative amount of endosperm and non-endosperm, is not a time-limiting factor. When relative flow rates are known for each stream, mass balance can be calculated from each intermediate stream in terms of the product (endosperm content) and the lower value non-endosperm byproduct. Data is presented from a purifier in a commercial flour mill. Intermediate streams collected from a run with optimized operational parameters were compared to those of another run before adjustment. The endosperm (product) mass balance profile for each run enabled assessment of operational efficiency. The devised chemical imaging analysis system would be particularly useful in commissioning of a new mill or to optimize existing wheat milling systems. Also, when raw material differs from that for which previous optimization was established, a new optimization may be in order. The ability to acquire a large number of spectra from a specimen and apply multivariate statistics to identify each pixel and subsequently count pixels accommodates heterogeneity and reports the results from averaging a very large number of individual spectra. A second illustration of the utility of the imaging method is presented centering on streams from the first and second break unit operations at the beginning of the roller mill process.  相似文献   
7.
In this study, optimal angle‐ply orientation of symmetric composite cylinders under fatigue loading is investigated. The fiber‐reinforced plastic cylinders were manufactured from E‐glass/epoxy. The layers were manufactured symmetrically in [±75°]2, [±60°]2, [±55°]2, and [±45°]2 orientations. Burst pressure of filament‐wound composite cylinders under alternating pure internal pressure was measured experimentally. Internal fatigue pressure testing method was applied to the composite cylinders in close‐ended condition. For this study, a PLC controlled hydraulic pressure testing machine has been employed. The static burst pressure values of specimens were measured; subsequently, fatigue test pressure was applied in 70, 60, and 50% stress levels of burst pressure for each orientation. Damage propagations of the composite cylinders on these stress levels were observed as whitening, leakage, and final failure for [±60°]2, [±55°]2, and orientations. When the damage propagation of [±75°]2 angle‐ply cylinder was observed, whitening and leakage did not occur and final failure occurred suddenly. Stress‐cycle curves obtained from the tests are given in graphics. Experimental results reveal that variation in stress levels and the winding angles have considerable effects on final failure cycles, which is also presented graphically. The optimum winding angle for the composite pressure cylinders or vessels under internal fatigue pressure load was obtained as [±45°]2 orientation. POLYM. COMPOS., 2010. © 2009 Society of Plastics Engineers  相似文献   
8.
The propagation kinetics of ethyl methacrylate (EMA) and ethyl α-hydroxy methacrylate (EHMA) has been subject to a computational study to understand their free radical polymerization (FRP) behavior in bulk and in solution using Density Functional Theory (DFT). The propagation of EHMA is studied in ethanol and toluene to assess the effect of hydrogen-bonding solvents on FRP of monomers with α-hydroxy functionality. Although EMA and EHMA resemble each other in structure, EHMA propagates faster in bulk due to the presence of intermolecular hydrogen-bonds, which tend to facilitate the approach of the propagating species. This falls in contrast with the experimentally observed lower propagation rates of EHMA in ethanol compared to toluene. Calculations show that the 2.28 rate acceleration in toluene is governed by the ratio of the pre-exponential factors, which reflect the entropies of activation, in both media. The polar protic solvent ethanol has a disruptive effect via hydrogen-bonding on the 6-membered ring shape of EHMA monomers thus decreasing the entropy of activation of the reaction. In the case of toluene, there are no special interactions with the hydrophobic solvent, the entropy of activation is higher than in ethanol.  相似文献   
9.
10.
Experiments were carried out in a half slot-rectangular spouted bed to investigate the effects of slot width and lower section basal angle on column hydrodynamics. Flow regimes, minimum spouting velocity, spouting and maximum pressure drops, and maximum spoutable bed height were determined for 4 mm diameter polyethylene particles. The results are compared with those for conventional cylindrical and rectangular spouted beds. Correlations for each hydrodynamic parameter are developed and compared with equations available in the literature.  相似文献   
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