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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.
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   
3.
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   
4.

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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5.
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   
6.
Effect of edible coatings on the quality of frozen fish fillets   总被引:7,自引:0,他引:7  
The objective of this study was to determine the changes in the quality of coated trout fillets after coating with edible materials. Fillets were coated and stored at −18 °C for a period lasting up to 7 months. Coating materials were applied in three different stages (first, second, and last coatings). The coated fillets were fried and analyzed for oil absorption and moisture content throughout the storage period. Sensorial attributes and the physical-biochemical changes were also measured before the frying process in each month. It was observed that it is more advantageous to use gluten as the first coating, xanthan gum as the second coating, and wheat (W) and corn (C) flours in the ratio of 1:1 or 2:1 as the last coating. In terms of the fillet quality, the following results were obtained in the analyses conducted before frying. The lowest pH found was 6.25 in zein-containing samples and 6.30 in guar-containing samples. The effects of the last coatings on pH were unimportant (P > 0.05). The lowest thiobarbituric acid levels found were 2.07 mg kg in the fillets coated with casein mixture, 2.44 mg kg in the fillets coated with xanthan gum, and 2.25 mg kg in the fillets coated with W:C flour mixture in the ratio of 2:1. The lowest total volatile basic nitrogen levels found were18.06 mg 100 g in the fillets coated with casein mixture, 18.62 mg 100 g in the fillets coated with xanthan gum, and 18.47 mg 100 g in the fillets coated with W:C flour mixture at 1:1 ratio. In the sensorial analysis, the coated samples were much more preferred than those not coated. As a result of the effects of all the materials, the coating layers on the meat surface provided more resistance against mass transfer during storage.  相似文献   
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9.
In this study, the steady and dynamic rheological properties of the dairy dessert samples (puddings) containing carrageenan, alginate, guar and xanthan gums and their combinations were investigated in a model system, and mixture design was utilized to observe the effects of the gums and their interactions. The flow behaviour of the pudding samples fitted to the Ostwald de Waele model (R 2?>?0.98). All the samples exhibited a gel structure with their higher G′ (storage modulus) values than the G″ (loss modulus) values. Carrageenan was the most effective hydrocolloid on both the steady and dynamic rheological parameters of the dairy dessert samples. On the other hand, alginate had relatively smaller effect. Furthermore, 30 pudding samples containing different gum or gum combinations were classified into two groups (A and B) by using principal component analysis (PCA). Samples containing more than 33% carrageenan in their formulations made up the group A which positively correlated to K (consistency index), η 50 (apparent viscosity at shear rate 50 s?1), G′, G″, G* (complex modulus) and η* (complex viscosity) values.  相似文献   
10.
In this study, four different fresh Kashar cheese samples were ripened for 90 days. The physicochemical properties, texture attributes, fatty acid composition and volatile compound profiles of the samples were measured every 30 days of ripening. The texture properties of the cheese samples were significantly affected by the duration of the ripening period. The results of this study highlighted that texture parameters as a function of ripening period should be considered for both fresh and aged Kashar cheeses to determine the ripening period as they are very important for consumer acceptability and consumption of the end product.  相似文献   
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