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In this paper, a new technique is introduced to obtain non-uniform Berry-Esseen bounds for normal and nonnormal approximations by unbounded exchangeable pairs. This technique does not rely on the concentration inequalities developed by Chen and Shao [4,5] and can be applied to the quadratic forms and the general Curie-Weiss model.

To collect information and statistical data regarding the current oral health care and dental education resources in China.Electronic databases were searched and a literature review conducted. The homepages of relevant universities and colleges were visited to collect dental education information. In addition, private conversations with related experts were conducted.Compared with the 3rd National Oral Health Survey (2005), the ratio of gingival bleeding in individuals aged 33 to 44 years has increased in the last 10 years. The average percentage of residents visiting departments of dentistry in public hospitals is less than 10%. The total number of dentists and assistant dentists increased to 167,227 in 2016, with a ratio of 1.21 per 10,000 people. There is a great imbalance in the distribution of dental practitioners among the provinces. There are 101 dental schools or departments of stomatology that provide 5-year dental training courses and offer bachelor's degrees in dentistry, with another 93 dental institutions offering shorter 3-year training courses for assistant dentists.The results of the present study show that there has been significant change during recent years in China. However, the ratio of dental practitioners to the population as well as the number of dental visits carried out is still much lower than in developed countries and does not satisfy the demand for dental care in China. The quality and quantity of dental education, including continuing dental education, calls for improvement in the future.

Objective Chronic periodontitis is a chronic inflammatory disease of the periodontal tissues and is caused by invasion of certain types of bacteria and Archaea , with Methanobrevibacter oralis as the predominant archaeon. In this study, we investigated the prevalence and quantity of the newly discovered Archaea phylotype Thermoplasmata in patients with chronic periodontitis. Methods Subgingival plaque samples were obtained from 49 patients with chronic periodontitis and 45 periodontally healthy subjects. Qualitative analyses of Archaea and class Thermoplasmata were carried out by amplification of 16S rRNA genes in DNA extracts from plaque samples, and all the samples were quantitatively analyzed by real-time polymerase chain reaction (PCR). Results The prevalence of Archaea in patients with chronic periodontitis was 69.4% according to the conventional PCR results, but was 87.8% according to real-time PCR. In the control group, three samples were detected as positive, but none of these were confirmed in qualitative analyses. The prevalence of class Thermoplasmata was 18.4% by nested PCR and 24.5% by quantitative PCR in the chronic periodontitis group. The prevalence of Thermoplasmata was significantly lower than that of total Archaea. The relative abundances of Archaea and Thermoplasmata varied among samples. Thermoplasmata were not the predominant archaeons in the subgingival dental plaque. Among the clinical parameters of patients with periodontitis, probing depth was positively associated with Archaea detection. Conclusions The existence of Archaea was correlated closely with the presence of chronic periodontitis. Thermoplasmata represented a minor archaeon in periodontal infection.

LDM process is used for preparing three-dimensional scaffolds for tissue engineering rapid prototyping technologies. Because of its forming process is complex, which influenced by a variety of factors, so the processing environment is not stable, the forming of scaffold pore size can not be guaranteed, therefore the forming precision is poor. However, the scaffold pore size accuracy is mainly decided by the wire filament width. Neural network theory and development provides a powerful tool for the study of nonlinear systems. This article analyzed the influence factors for forming bone scaffold filament width of LDM process, based on improved BP neural network, using MATLAB software programming, then predicted the filament width. The results show that model prediction error was less than 8%, it has high forecasting precision, and it can be used to guide the LDM process parameter selection and forming precision of prediction.

From the perspective of forming bone scaffold, the technologic parameters of LDM which have important influence on the shape of the deposition material are studied. Through building experimental platform and using chitosan solution as experimental material, the influence of the temperature and the layer height on the lap of every fiber layer are firstly discussed in detail. Besides, the effects of nozzle diameter, the velocity of receiving device, the pressure of feeding device are also discussed. Then the above mentioned process parameters are all optimized, which make the forming mechanism of LDM to be clear. Finally, based on the optimal parameters, the scaffold with self-designed pore size and a high degree of pore interconnectivity, which meeting the requirements of the structure of tissue engineering are fabricated.

The scaffold is a key part of the artificial regeneration osseous tissues. The ideal scaffold will have the ability to mimic the fully functional tissue, which can afford the fibrous form and complex function of the native ECM. Although Low-temperature deposition manufacturing is a promising method for fabricate tissue scaffold because scaffold can maintain a good performance of biomaterials in low temperature, the scaffold pore size can not be controlled according to demands. Therefore, the key factors that affect the pore size of bone scaffolds are firstly analyzed. Then the mechanism for on-line control is given. Finally, an automatic control system is proposed and some experimental results are given, which have demonstrated the effects of processing parameters on the Shaping of scaffold material.

Low-temperature deposition manufacturing (LDM) has been proven as an effective bone scaffold preparation process, but its further application has been seriously hindered by the existing material over-accumulation problem. In view of the over-accumulation problem of the traditional pneumatic extrusion material feeding way, designed and developed a feeding system based on pneumatic-extrusion and valve-control, which can achieve rapid pressure/relief, Combined with the inflation / deflation time calculation method of fixed volume container for analysis and calculation. A unified data management method of the material feeding device and a regulation scheme of the controller are given. Experimental results show that, by adjusting parameters, the feeding system based on pneumatic-extrusion and valve-control can achieve rapid gas pressure/relief, the flux has been well controlled, the over-accumulation on deposition path at the end has been eliminated, which lead to effective guarantee of scaffold forming quality.

A nanostructured surface layer was obtained on the surface of Zr-4 by surface mechanical attrition treatment(SMAT). The structure and the properties of the SMAT sample were analyzed by means of the optical microscope, hardness and polarization curve testing. The results show that， when processing time for 5min, the average grain sizes on the surface layer can be refined to 23nm. The average grain size by SMAT-ed for 15min is 20nm, which is the smallest. The microhardness have a significant increase, the surface roughness also increase, and the corrosion resistance reduce in 1mol H2SO4solution.

An innovative fabrication technique for the nanometer-sized SiGe/Si heterostructure was developed in this study. Ge was induced in Si substrate by two-step ion implantation. The spherical SiGe nanoclusters are self-assembled in the Si substrate by subsequent rapid thermal annealing at 1,100 °C. The diameter of the spherical SiGe nanoclusters is 5–7 nm. Visible photoluminescence from this nanometer-sized SiGe/Si heterostructure at room temperature was investigated. We found three peak energies of visible luminescence spectra at 1.97, 2.13, and 2.16 eV, respectively. The luminescence intensity depends on the number of the nanoclusters and will be decreased because of the micro-defects around the heterostructure, which is discussed in detail.

Electrospinning, which is a technology to make nano fiber, has quite high requirements of the speed of feeding. In order to solve the unstable phenomenon, salivation, and achieve the stability of quality, numerical simulation is used to compute the nozzle exit pressure and exit velocity, while recursive least squares is used to identify of the results of the simulation. At last, PID algorithm and recursive least squares methods are combined together to form a model for the feeding system controller. And the pneumatic device and pressure sensor are used to build electrospinning feeding system. Finally, experimental verification PEO solution is used to verify this method, no drooling electrospinning phenomenon happens

The Si1−xGex thin layer is fabricated by two-step Ge ion implantation into (0 0 1) silicon. The embedded SiGe nanoclusters are produced in the Si1−xGex layer upon further annealing. The number and size of the nanoclusters changed due to the Ge diffusion during annealing. Micro defects around the nanoclusters are illustrated. It is revealed that the change of Si–Si phonon mode is causing by the nanoclusters and micro defects.

Electrospinning is an effective and versatile technology to fabricate ultrafine nanofiber,however further development is urgently limited due to the low uniformity distribution and unpredictable feature of the fiber deposited. For that sake, experiment has been done and analyzed to address these problems. Relation between process physics-Taylor cone and fiber diameter characters has been discovered. Furthermore, the feature parameters of the Taylor cone are extracted effectively by CCD detection and image processing. The above experiments results and processing data is analysis and examed by the steady jet theory. This paper offers significant theoretical guidance and technical support to the online control of electrospinning fiber diameter.

Sasobit has been applied into asphalt successfully since 1997. From then on, a lot of studies emphasizes on how Sasobit can lower asphalt’s viscosity and reduce poison odor emission. However, the durability of asphalt containing Sasobit is ignored to research. This paper aimed to analyze Sasobit impact on the durability of asphalt. In this study, the Sasobit modified asphalt was blended using different Sasobit contents of 2%, 3%, 4% and 5% by weight of asphalt into the base asphalt (SBS modified asphalt). The Rolling Thin Film Oven test (RTFO) and Pressure Aging Vessel test (PAV) were conducted to simulate the mixing and construction aging and in-service aging of asphalt. The properties and micro-structure of the base asphalt and Sasobit modified asphalt in three different aging states (original state, mixing and construction aging state and in-service aging state) were tested by using the Penetration-Grade system, Performance-Grade system and fluorescence microscope. The aging indexes of the base asphalt and Sasobit modified asphalt were calculated to compare their durability. It was evident that the durability of the Sasobit modified asphalt was mostly affected by the type of base asphalt and Sasobit had a little impaction on the durability of the asphalt.

When electrospinning has been used as a special technology of regenerative bone scaffold, for raising the efficiency of electrospinning and decreasing collecting area, the mechanism of bending instability was analyzed and concluded that the force of electric field is a key factor. Auxiliary gradient rings have been added to electric field, which changed the environment of electric filed. Then, it was verified that additive gradient rings could reduce the collecting area. On the other hand, Maxwell was used to analyze the strength and structure of electric field. The maximum intensity of electric field existed in the position of nozzle. The farther apart from nozzle, the rapidly intensity decreased. When auxiliary gradient rings had been added, the intensity of instability stage showed increased trend. Mechanism analysis and experimental result were confirmed by the simulation effectively.

The purpose of this study was to evaluate the clinical effects of photodynamic therapy (PDT) for scaling and root planing (SRP) in the treatment of chronic periodontitis.PDT has become a potential treatment of infectious diseases with the development of laser medicine. However, there are very limited data from clinical trials to evaluate the effect of PDT in the treatment of periodontitis.Fifty-eight patients with chronic periodontitis were included and divided into three groups. They were treated with SRP alone, SRP followed by one PDT, or SRP followed by two PDT treatments. PDT was performed at sites with a probing depth (PD) ≥5 mm by using Periowave(TM) therapy. Periodontal values of bleeding on probing (BOP), PD, and clinic attachment loss (CAL) were examined at baseline, 6 wk after treatment, and 12 wk after treatment.Compared with the baseline, sites with baseline PD ≥5 mm in all three groups showed significant reductions of PD, CAL, and BOP at 6 and 12 wk after treatment. Although there were no differences between the three groups for PD and CAL in all three examinations, the presence of BOP sites at 12 wk, but not 6 wk, after SRP treatment significantly decreased in groups with PDT in comparison with SRP alone.PDT may serve as an adjunctive therapy to SRP treatment in periodontal pockets with PD ≥5 mm to reduce the presence of bleeding in these lesions.

Based on the analyzing for strengths and weaknesses of the rapid prototyping (RP) and electrospinning technique in the manufacturing of three-dimensional bone scaffold, the defects including RP’s low precision and electrospinning’ low intensity has been found. Accordingly, composite structure forming (CSF) has been proposed. This approach integrates the advantage of rapid prototyping and electrospinning. Furthermore, the modeling method of Scaffold for composition forming has been proposed .At the end, the method of controlling process has been given.

Previous studies have assumed that amelogenin is responsible for the therapeutic effect of the enamel matrix derivative (EMD) in periodontal tissue healing and regeneration. However, it is difficult to confirm this hypothesis because both the EMD and the amelogenins are complex mixtures of multiple proteins. Further adding to the difficulties is the fact that periodontal tissue regeneration involves various types of cells and a sequence of associated cellular events including the attachment, migration and proliferation of various cells. In this study, we investigated the potential effect of a 25-kDa recombinant porcine amelogenin (rPAm) on primarily cultured periodontal ligament fibroblasts (PDLF), gingival fibroblasts (GF) and gingival epithelial cells (GEC). The cells were treated with 25-kDa recombinant porcine amelogenin at a concentration of 10 microg/mL. We found that rPAm significantly promoted the proliferation and migration of PDLF, but not their adhesion. Similarly, the proliferation and adhesion of GF were significantly enhanced by treatment with rPAm, while migration was greatly inhibited. Interestingly, this recombinant protein inhibited the growth rate, cell adhesion and migration of GEC. These data suggest that rPAm may play an essential role in periodontal regeneration through the activation of periodontal fibroblasts and inhibition of the cellular behaviors of gingival epithelial cells.

In this paper, the strength and deformation of an elastic orientating component (sleeve) were analyzed by Finite Element Method (FEM). The highest stress of the part and the relationship between the dimension and deformation were found. The position under the critical situation was obtained. The optimal dimension of the sleeve was given.

SiGe nanoparticles with uniform diameter of about 30 nm in the top silicon of silicon on insulator (SOI) were synthesized by Ge ion implantation combined with subsequent annealing process. The density of those nanoparticles is 6 × 10 7 /cm 2 . These nanoparticles are formed by agglomeration of the recoil atoms and the migrated adatoms. The method presented in this study will allow efficient fabrication of uniform SiGe nanoparticles into SOI.

To analyze the relation of virulence properties and pathogenicity of Porphyromonas gingivalis (P.gingivals) isolated from Chinese patients.Based on the previous analysis of virulence properties, investigations of pathogenicity properties, including the adhesion to host cells, gingipain activities, and resistance to host immune reaction were performed to analyze the diversity of pathogenic properties of these strains. SAS 8.02 software package was used for statistical analyses.Less-virulent type strain showed higher adherence ability to host red blood cells and weaker resistance to serum killing, while virulent type strain showed the opposite reactions. However, the clinic isolates presented just the opposite relationship between virulence properties and pathogenicity. In addition, there was no obvious correlation between gingipain activities and virulence properties of P. gingivalis strains.The results suggested that there is no obvious linkage between the P. gingivalis virulence properties and pathogenicity diversity.

To study the clinical effect of osteotome sinus floor elevation (OSFE) combined with simultaneous implant placement in the treatment of edentulous posterior maxilla subject to insufficient bone height in the periodontally compromised patients.Forty-seven Straumanns implants were placed in the posterior maxilla in 35 patients with the procedure of OSFE. The final prostheses were restored after 3 to 6 months. The follow-up period was 6 to 30 months. Radiographs were taken and PD, PLI, BOP were measured and analyzed.The overall survival rate was 95.74% during the study period. Forty-five out of the 47 implants were clinically stable and loaded without pain or any subjective sensation. The perforation ratio of the membrane was 4.26%. The average of PD around the implants was (3.22±1.07) mm. The average of the marginal bone loss was (1.38±0.59) mm.OSFE without bone graft proves to be an effective and predictable treatment for atrophic edentulous posterior maxillary region in patients with periodontitis, but the long-term effect needs further observation.

To determine whether an elevated neutrophil-lymphocyte ratio (NLR) is negatively associated with tumor recurrence in patients with hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC) after liver transplantation (LT), and to determine the optimal predictive NLR cut-off value.The data of HCC patients who had undergone LT came from the China Liver Transplant Registry database. We collected data from 326 liver cancer patients who had undergone LT at our medical center. We divided the patients into groups based on their NLRs (3, 4 or 5). We then compared the clinicopathological data and long-time survival between these groups. Meanwhile, we used receiver operating characteristic analysis to determine the optimal NLR cut-off.Of 280 HCC patients included in this study, 263 were HBV positive. Patients with an NLR3 and patients with an NLR ≥ 3 but4 showed no significant differences in overall survival (OS) (P = 0.212) or disease-free survival (DFS) (P = 0.601). Patients with an NLR ≥ 4 but5 and patients with an NLR ≥ 5 also showed no significant differences in OS (P = 0.208) or DFS (P = 0.618). The 1-, 3- and 5-year OS rates of patients with an NLR4 vs an NLR ≥ 4 were 87.8%, 63.8% and 61.5% vs 73.9%, 36.7% and 30.3%, respectively (P0.001). The 1-, 3- and 5-year DFS rates of patients with an NLR4 vs NLR ≥ 4 were 83.9%, 62.9% and 60.7% vs 64.9%, 30.1% and 30.1%, respectively (P0.001). Univariate and multivariate analyses demonstrated that three factors, including NLR ≥ 4 (P = 0.002), were significant predictors of tumor recurrence in HCC patients after LT.A preoperative elevated NLR significantly increased the risk for tumor recurrence in HCC patients after LT.

To investigate the virulent properties of P. gingivalis clinical strains.By using mouse abscess model (MAM), six P. gingivalis clinical strains, L2, L3, L4, L5, L11 and L12 were subcutaneously inoculated into the central back of BALB/C mice. The clinical signs of the mice were observed and the virulent properties of the clinical strains were analyzed by comparison with type strains of W83 and ATCC 33277. SPSS11.5 software package was used for statistical analysis.According to the criteria established in previous reports, L3, ATCC33277, and W83 produced a localized abscess at the site of injection and were categorized as noninvasive. L2, L5, L11, and L12-induced lesions spread to distant organs and may produce severe systemic reactions and these strains were classified as invasive.Clinical strains from Chinese patients showed similarities to type strains in MAM. The virulent properties of P. gingivalis clinical strains are quite different from each other.

To analyze bacteria community structure changes in subgingival plaque after initial therapy, and to provide experimental evidences for clinical decision.Six patients with chronic periodontitis were chosen. Subgingival plaque samples, as well as clinical indexes, were collected at baseline and six weeks after initial therapy. The generated two different 16S rDNA fragments of subgingival plaque samples were separated by denaturing gel, creating bands patterns representative of community structure. Subsequent cluster analysis was made.The clinical indexes were improved significantly. The diversity of population of clinical subgingival samples was not significantly different between baseline and 6 weeks after initial therapy. Through cluster analysis, it was confirmed that same patient got similar subgingival plaque between baseline and 6 weeks after treatment.Same patient tend to get similar subgingival plaque between baseline and after initial therapy. DGGE can detect the microbial composition of subgingival plaque.

We have fabricated SiGe quantum dots (QDs) by means of a two-step Si ion implantation followed by thermal rapid thermal annealing (RTA) method. SiGe QDs with the 4–6 nm diameter are formed uniformly in the near-surface region of Ge substrate. The RTA processes are performed at 800 and 900 °C for 15 s, respectively. Both experimental and theoretical analysis indicates that the higher temperature (900 °C) RTA can enhance the growth of SiGe QDs. Two photoluminescence peaks are observed near 572 and 581 nm at room temperature. The mechanism of the luminescence from SiGe QDs is discussed.

MicroRNAs (miRNAs) have been demonstrated to play an important role in regulation of the immuno-inflammatory response; however, the function of miRNAs in periodontal inflammation has not been investigated. The objective of this study was to explore the properties of miRNAs in periodontal inflammation by comparing miRNA profiles of inflamed and healthy gingival tissues. Gingival tissues were obtained from 10 periodontitis patients and 10 healthy subjects. After RNA extraction, miRNA profiles were analyzed by microarray, and expression levels of selected miRNAs were confirmed by real-time quantitative reverse transcription polymerase chain reaction (RT-PCR). Analyses using two computational methods, Targetscan and MicroRNA.org, were combined to identify common targets of these miRNAs. Finally, the individual miRNA expression levels of three toll-like receptor (TLR)-related miRNAs from inflamed and healthy gingival tissues were evaluated by RT-PCR. Ninety-one miRNAs were found to be upregulated and thirty-four downregulated over two-fold in inflamed gingival tissue compared with those in healthy gingival tissue. Twelve selected inflammatory-related miRNAs, hsa-miR-126*, hsa-miR-20a, hsa-miR-142-3p, hsa-miR-19a, hsa-let-7f, hsa-miR-203, hsa-miR-17, hsa-miR-223, hsa-miR-146b, hsa-miR-146a, hsa-miR-155, and hsa-miR-205 showed comparable expression levels by microarray and real-time quantitative RT-PCR analyses. In addition, the putative inflammation targets of these miRNAs were predicted, and three that were tested (hsa-miRNA-146a, hsa-miRNA-146b, and hsa-miRNA-155), showed significant differences between inflamed and healthy gingiva. This remarkable difference in miRNA profiles between periodontal diseased and healthy gingiva implicates a probable close relationship between miRNAs and periodontal inflammation. The data also suggest that the regulation of TLRs in periodontal inflammation may involve miRNA pathways.

This paper addresses the problem of fetal electrocardiogram (FECG) extracion using recursive least squares (RLS) and normalized least mean squares (NLMS) adaptive algorithms based adaptive noise canceling (ANC) approach. The simulation results are compared with the classical adaptive filters, such as RLS, NLMS and LMS algorithms, for eliminating the maternal electrocardiogram (MECG) and hence to extract the FECG. The comparative study has been carried out to show that the performance and accuracy of the recursive least squares adaptive noise cancelling(RLS-ANC) approach is more effective than the normalized least mean squares (NLMS) algorithm in an adaptive manner, and it is found to converge faster than NLMS algorithm in ANC.