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Magnetic agglomeration of CoB nanoparticles in the hydrogen production from the hydrolysis of NaBH4 aqueous solution always degrades their catalytic activity. This work aims at the rational development of robust supported CoB catalyst that is active and stable towards NaBH4 hydrolysis. In this study, PANI nanotubes derived from PS nanofiber templates are firstly synthesized by the polymerization of aniline followed by the template removal. CoB nanoparticles are then decorated into PANI nanotubes via an impregnation and chemical reduction method. It can be found that CoB nanoparticles can be confined into the internal surface of PANI nanotubes which improves the dispersion and anchored stability of CoB nanoparticles. The as-prepared CoB/PANI composite catalyst exhibits a high catalytic performance and recycling stability. The hydrogen production rate as high as 2300 ml. min−1. g − 1 is achieved and the activation energy was calculated to be only 37.75 kJ/mol. Meanwhile, CoB/PANI catalyst displays excellent stability in NaBH4 hydrolysis during five cycles. The experimental results indicated that as-synthesized CoB/PANI composite catalysts are very efficient towards hydrogen production from NaBH4 hydrolysis.

Agglomeration of CoB catalysts is a severe problem in hydrogen generation from NaBH4 hydrolysis. Herein, highly dispersed carbon nanofiber immobilized CoB catalysts (CoB/CN) were synthesized by a combined prereduction and carbonization method, which is used in hydrogen generation from NaBH4 hydrolysis. Morphological evolution of carbon nanofibers, phase structure and elemental distribution of CoB/CN catalysts are explored by X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). Compared to Co/carbon nanofiber catalysts (Co/CN) without prereduction, CoB/CN catalysts can afford higher CoB dispersity and specific surface area because the migration rate of cobalt species during carbonization is effectively retarded by prereduction. Hence the agglomeration of magnetic CoB nanoparticles can be effectively inhibited. The hydrogen generation experiment shows that CoB/CN catalysts process higher catalytic activity and lower activation energy than Co/CN.

Robust multiperson tracking requires the correct associations of online detection responses with existing trajectories. In this paper, we propose to integrate multiple cues to resolve the ambiguities in data association for multiperson tracking. Unlike most existing algorithms which integrate multiple cues in the same manner for different scenes, we learn scene-specific parameters to integrate multiple cues for different scenes, as the discriminative power of each cue may vary in different scenes. The scene-specific integration parameters are learned offline by supervised learning method. Min-cost multicommodity flow is employed to solve the data association task. The edge cost of the multicommodity network, which is crucial for the data association, is determined by integrating the multiple cues extracted from the detection response based on the learned scene-specific integration parameters. The experimental results on public multiperson tracking data set demonstrate the effectiveness of the proposed scene-specific integration method.

Recruiting periapical stem cells into the root canal and inducing their odontogenic differentiation are both vital for pulp regeneration. This study was aimed at developing a kind of bioactive composite scaffolds (G/PSC scaffolds) by combining the pH-neutral bioactive glass named PSC and gelatin. The incorporation of PSC endowed the scaffolds with bioactivity and enhanced its resistance to enzymatic hydrolysis in vitro while maintaining its high water absorption capacity. The G/PSC scaffold with a PSC content of 0.5 mg/mL in 3% gelatin solution showed the best overall performance, released large amounts of silicate ions and maintained a neutral pH after soaking in simulated body fluid (SBF). Human bone marrow mesenchymal stem cells (hBMMSCs) developed good cell morphology with affluent pseudopods on the G/PSC scaffold and infiltrated fairly deep into it. Additionally, hBMMSCs showed increased proliferation and mRNA expression levels of dentin sialophosphoprotein (DSPP), dentin matrix protein 1 (DMP-1), alkaline phosphatase (ALP), collagen type I (Col-I), osteocalcin (OCN), and runt-related transcription factor 2 (Runx2). The present results demonstrated that the G/PSC scaffold significantly promoted hBMMSC chemotaxis, proliferation and odontogenic differentiation. Therefore, the G/PSC scaffold is a promising material for pulp regeneration.

This work focused on fabricating mesoporous bioactive glass nanospheres with large pore (LMBGs) by means of a biphase delamination approach and the self-assembly of the reactants took place at the oil-water interface. The morphology and mesostructure of LMBGs were investigated and the results demonstrated that the well-dispersed LMBGs with a radial mesoporous structure and large pore size could be easily tuned by adjusting the reaction temperature using hexadecyl trimethyl ammonium bromide (CTAB) as a template agent and triethanolamine (TEA) as a hydrolysis catalyst. The special structure and outstanding property of LMBGs probably endowed it with a bright prospect in the application of drug delivery systems.

The aims of this study were to compare the osteogenic effects of a novel nano-sized bioactive glass (BG) and a traditional micron-sized BG, and to verify whether mitogen-activated protein kinases (MAPKs) are involved and play a part in BG’s osteoblast gene activation. It was found that the effect of a nano-sized BG on MAPK phosphorylation is better than the traditional 45S5 BG. We prepared extractions of the novel nano-sized 58S BG and traditional 45S5 BG and compared their effect on osteoblast-like cells’ (MG-63 cell) proliferation, osteogenic gene and protein expressions, matrix mineralization and MAPK activation. We further investigated the signal transducing effect of the MAPK pathway on the BG’s osteogenic gene activation. Our results showed that nano-58S extraction enhanced the MG-63 cells’ proliferation and osteogenic gene expressions of alkaline phosphatase (ALP), collagen type I (Col I), Runt-related transcription factor 2 (Runx2) and osteocalcin (OCN). The results of ELISA showed more Col I and OCN protein production in the BG groups than in the control group. Greater mineralized nodule formation was found in the nano-58S BG group using alizarin red S staining. We also found that nano-58S and 45S5 BG activated MAPKs, specifically the ERK and p38 pathways, using western blotting. After blocking the ERK or p38 pathway, real-time PCR showed the osteogenic gene activation induced by the BG extractions was inhibited. Blocking the ERK pathway induced a more obvious inhibitory effect on the genes’ normal expression and activation. The significance of this study is that we found that the ERK and p38 MAPK pathways are involved and play an important part in BG’s osteogenic gene activation. The effect of the nano-sized BG on MAPK phosphorylation, osteogenic gene activation, and osteoblast differentiation and mineralization is better than the traditional 45S5 BG.

Phytic acid derived bioactive calcium phosphosilicate (PSC) glasses with a high phosphate content were synthesised by using non-toxic phytic acid as a phosphorus precursor. This study aimed to verify the effects of PSC on the odontogenic differentiation and dentin–pulp complex-like tissue regeneration of dental pulp cells (DPCs). Nitrogen adsorption, field-emission scanning electron microscopy, Fourier transform infrared spectroscopy, pH measurement, and inductively coupled plasma optical emission spectroscopy analyses were performed to characterise PSC. Classical 45S5 bioactive glasses (45S5) were used as positive control. Cell proliferation (1, 3, 5, 7 and 9 days), odontogenic-related gene expression levels (3 and 7 days) and mineralisation ability (21 days) of human DPCs (hDPCs) were evaluated with methylthiazol tetrazolium assay, real-time polymerase chain reaction and alizarin red staining after hDPCs from third molars were treated with PSC or 45S5 extractions. Rat molar crowns with pulp tissues covered by PSC or 45S5 were transplanted subcutaneously into nude mice for 2 and 6 weeks to demonstrate their biological effects in vivo. Results revealed that the specific surface area of PSC was larger than that of 45S5. The PSC also induced hydroxycarbonate apatite precipitation earlier than 45S5. pH was slightly increased when the amount and dissolution time of PSCs were increased. By comparison, pH was remarkably increased by 45S5. The amounts of Si and P ions released by PSC (0.1 mg mL−1) were larger than those released by 45S5. Cell proliferation, mRNA expression levels of dentin sialophosphoprotein, dentin matrix protein 1 and osteocalcin and mineralisation of hDPCs were also more strongly promoted by PSC than by 45S5. In vivo, the amount of induced typical dentin-like tissues with odontoblast-like cells generated on the interface between materials and pulp tissues was higher in PSC than in 45S5. Only collagen-like tissues were observed in groups without bioactive glasses. These findings suggested that PSC enhanced the odontogenic differentiation of DPCs and dentin–pulp complex-like tissue regeneration. The PSC might be a potential candidate for vital pulp preservation and regeneration of the dentin–pulp complex.

The object of this study was to evaluate the effect of bioactive glass (BG) size on mineral formation on dentin surfaces. Totally demineralized dentin discs were treated using BG suspensions with different particle sizes: i.e. , microscale bioactive glass ( m -BG), submicroscale bioactive glass ( sm -BG) and nanoscale bioactive glass ( n -BG). Field-emission scanning electron microscopy and 3D profile measurement laser microscopy were used to observe the surface morphology and roughness. It was found that all BG particles could promoted mineral formation on dentin surfaces, while plug-like depositions were observed on the dentin discs treated by n -BG and they were more acid-resistant. The present results may imply that n -BG has potential clinical application for dentin hypersensitivity treatment.

Introduction This study aimed to evaluate the potential applications of polycaprolactone (PCL)/submicron bioactive glass (smBG) hybrid composites for pulp and dentin tissue regeneration. Methods PCL/smBG hybrid composites were made with novel monodispersive bioactive glass submicrospheres, and pure PCL and bioactive glass samples were used as controls. Surface characteristics were assessed by scanning electron microscopy. Crystalline apatite deposition in vitro was examined after incubation in simulated body fluid. Inductively coupled plasma spectroscopy was used to further analyze the concentration of Si ions released by the scaffolds. Cell adhesion and morphology of human dental pulp cells were observed by immunofluorescence staining. The proliferation and expression of odontogenic-related markers were subsequently investigated using the Cell Counting Kit-8 assay (Beyotime Institute of Biotechnology, Jiangsu, China), Western blotting, and real-time reverse-transcription polymerase chain reaction. Mineralization activity was assessed by alizarin red staining. Results Crystalline apatites were precipitated on the PCL/smBG hybrid and pure bioactive glass surfaces after incubation in vitro , and pure PCL did not exhibit precipitation. Surface deposition on PCL/smBG hybrids presented different topographies and was thicker than on pure bioactive glass scaffolds at a later stage. Human dental pulp cells had a significantly higher proliferation rate on the PCL/smBG hybrid than on the bioactive glass and PCL scaffolds. Furthermore, the integration of smBG into the hybrid scaffold significantly promoted the expression of markers for odontogenic differentiation. More mineralized nodules were generated in the PCL/smBG group than in the other 2 groups. Conclusions PCL/smBG hybrid composites may serve as potential material for pulp repair and dentin regeneration. The physical and chemical properties of the bioactive glass component affect the bioactivity of hybrid composites.

In this paper, we propose a novel convolutional neural network (CNN) based tracking framework, which aggregates multiple CNN features from different layers into a robust representation and realizes real-time tracking. We found that some feature maps have interference for effectively representing objects. Instead of using original features, we build an end-to-end feature aggregation network (FAN) which suppresses the noisy feature maps of CNN layers. The feature significantly benefits to represent objects with both coarse semantic information and fine details. The FAN, as a light-weight network, can run at real-time. The highlighted region of feature maps obtained from the FAN is the tracking result. Our method performs at a real-time speed of 24fps while maintaining a promising accuracy compared with state-of-the-art methods on existing tracking benchmarks.

Introduction This study aimed to investigate dental pulp responses to novel bioactive glass (BG) pulp capping materials after direct pulp capping in vivo . Methods Novel BG pulp capping materials are composed of powder and fluid. The powder is BG (82.36% SiO 2 , 15.36% CaO, and 2.28% P 2 O 5 ), and the fluid is provided in 2 kinds: (1) phosphate buffer solution (BG-PB) and (2) phosphate buffer solution with the addition of 1 wt% sodium alginate (BG-PB-SA). After mixing the powder and fluid, BG-PB and BG-PB-SA were prepared. Cavities with mechanical pulp exposure were prepared on maxillary first molars of Wistar rats. The exposures were randomly capped with BG-PB, BG-PB-SA, or mineral trioxide aggregate (MTA). After 1 ( n = 6) and 4 weeks ( n = 8), maxillary segments were obtained and prepared for histologic analysis with a scoring system. Statistical analysis was performed using the Kruskal-Wallis and Mann-Whitney U tests with the significance set at .05. Results After 1 week, few inflammatory cells were present in the BG-PB, BG-PB-SA, and MTA groups. Moreover, a thin layer of newly generated matrix was observed in most specimens. After 4 weeks, all specimens from the 3 groups formed a heavy dentin bridge. BG-PB and BG-PB-SA groups exhibited no or slight inflammatory response, whereas the MTA group exhibited a slight to moderate inflammatory response. No significant difference was observed in pulp inflammation and dentin formation among the 3 groups at either time point ( P > .05). Conclusions When used as a pulp capping agent, BG-PB and BG-PB-SA had similar favorable cellular and inflammatory pulp responses to those of MTA. Therefore, BG is a promising pulp capping material.

Correlation filters have recently made significant improvements in visual object tracking on both efficiency and accuracy. In this paper, we propose a sparse correlation filter, which combines the effectiveness of sparse representation and the computational efficiency of correlation filters. The sparse representation is achieved through solving an l0 regularized least squares problem. The obtained sparse correlation filters are able to represent the essential information of the tracked target while being insensitive to noise. During tracking, the appearance of the target is modeled by a sparse correlation filter, and the filter is re-trained after tracking on each frame to adapt to the appearance changes of the target. The experimental results on the CVPR2013 Online Object Tracking Benchmark (OOTB) show the effectiveness of our sparse correlation filter-based tracker.

This study aimed to evaluate the dentinal tubule penetration and filling quality of a bioceramic sealer (iRoot SP). Forty-two roots of extracted adult lower incisors were selected. After instrumentation with Protaper Universal to F3, 40 roots were chosen and randomly divided into 4 groups, as follows: iRoot SP single cone group, iRoot SP warm vertical group, AH Plus single cone group, and AH Plus warm vertical group. Before root canal filling, sealers were mixed with Rhodamine B dye for visualization under confocal laser scanning microscope. All samples were sectioned at 2, 4, and 6 mm to apex. Then, the percentages of void areas, gap regions, and segments of sealer that penetrated into dentinal tubules in each section were calculated. Non-parametric test was used for statistical analysis (α = 0.05). We found that filling techniques and types of sealer had no statistically significant effects on the occurrence of voids and gaps. The segments of iRoot SP penetrated into dentinal tubules were statistically more than that of AH Plus in both single cone and warm vertical techniques at 2 mm to apex (P < 0.05). Regardless of the filling technique used, iRoot SP can achieve comparable filling quality and better dentinal tubules penetration than AH Plus. Considering the good bioactivity of iRoot SP, it may help improve the seal of root canal system.

The correct associations of detections and tracklets are the key to online multi-person tracking. Good appearance models can guide data association and play an important role in the association. In this paper, we construct a discriminative appearance model by using metric learning which can obtain accurate appearance affinities with human appearance variations. The novel appearance model can significantly guide data association. Furthermore, the model is learned incrementally according to the association results and its parameters are automatically updated to be suitable for the next online tracking. Based on an online tracking-by-detection framework, our method achieves reliable tracking of multiple persons even in complex scenes. Our experimental evaluation on publicly available data sets shows that the proposed online multi-person tracking method works well.