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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.

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

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.

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.

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.

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.

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.