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A risk assessment for storm surge disasters can provide scientific support for coastal management as well as marine disaster prevention and mitigation. By taking the Wenchang City of Hainan Province as a pilot area, a risk assessment approach for typhoon-induced storm surge disasters is introduced in detail in this article. First, a numerical simulation system for storm surge inundation is developed, which is applied for the simulation and calculation of the probable maximum storm surge in Wenchang, and the obtained inundation areas and depths are used to assess the storm surge hazard. Then, the data of land use and disaster-bearing bodies are used to classify and assess the vulnerability of Wenchang. Finally, by taking the community as unit, the risk assessment for typhoon-induced storm surge affecting Wenchang is performed by combining the assessment results of both hazard and vulnerability, thereby obtaining a level map of risk distribution. The results show that there are risks of typhoon-induced storm surge in most of the coastal areas of Wenchang, especially for its northeast and east coastal areas, where the risks reach Levels I–II. This approach can be conveniently applied to risk assessments of storm surge in other coastal areas. Note that this approach focuses on the current risk of typhoon-induced storm surge in coastal areas, and further studies will be conducted on the assessment methods for the potential risk.

Zirconia are widely employed as a bone-substitute material for surgical implants due to its biocompatible and mechanical properties. However, implants introduced into the human undergo detachment from the host tissue due to poor biological performance. The laser-texturing can enhance the biological performance of the surface by altering surface properties and maintaining the bulk properties of the zirconia. In this work, laser-texturing microstructure features on zirconia are carried out to modify surface characteristics. Wettability are evaluated through water contact angles (WCAs) measurements. To characterize the influence of laser-texturing on pattern morphology, the produced surfaces are measured by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD). Micro cracks with melted material flowing along the scanning tracks in the untreated areas were observed from SEM. XRD results, in turn, show that the tetragonal → monoclinic phase transformation leads to many tiny cracks around the transformed particles. Wettability can be attributed to the modifications of the surface's microstructure depending on laser parameters and chemical composition. The stability tests prove that the super-hydrophobic surfaces produced by laser-texturing possess good abrasion resistance. This work may provide a simple method for producing zirconia surfaces with controlled wettability with the proper choice of laser parameter for extremely extensive industrial applications.

In bone tissue engineering, the structure of a scaffold is very important for cell growth and bone regeneration. It is better to make the scaffold resemble the native cancellous bone because natural cancellous bone can promote scaffold revascularization, which then accelerates cell proliferation. This study presents a parameterized design and fabrication method for cranial scaffold construction. A native human cranial sample was first scanned using micro computed tomography (CT), followed by 3D reconstruction, after which the internal structure of the bone trabecula was created. Based on an extracted negative bone trabecula model, the design components of “cavity”, “connecting pipe” and “spatial framework” were proposed to describe the scaffold model. Then, by using the parameterized component model and an assembly and deformation algorithm, the bionic scaffold was designed. Its porous distribution, connection, porosity and area size were easily controlled. Finally, a biomaterial scaffold case was fabricated using a gelcasting process, and cell culture testing was performed in vitro to verify the scaffold's biocompatibility. The results show that the scaffold can promote cell growth and that cells accumulate in the form of a mass within three days.

Wear is one of the main forms of tool failure during machining. The prediction of tool wear is of great significance for ensuring the high quality of the workpiece. In order to improve prediction accuracy of tool wear, a tool wear prediction model based on singular value decomposition (SVD) and bidirectional long short-term memory neural network (BiLSTM) is proposed. The cutting force signal is taken as the monitoring signal. Firstly, the raw cutting force signal is reconstructed by Hankle matrix, and the SVD of the reconstructed matrix is performed to extract the signal features. Then, SVD features of the current sampling period and the previous four sampling periods are taken as the input, and the tool wear prediction value at the current time is obtained based on the BiLSTM. The experimental results show that the proposed SVD-BiLSTM model can effectively predict the tool wear and obtain higher prediction accuracy than other comparison models.

In skull bone tissue engineering, cells do not easily survive and proliferate in the scaffold because of the lack of nutrient transport channels. To address these problems, a vascular design and fabrication method based on human skull diploic vein characteristics was proposed. The skull sample was scanned by micro-CT, and the 3D model was constructed by Avizo. By analyzing the characteristics of the diploic vein, the vascular centerline model, path model, taper model and bifurcation model were proposed. Two vascular network examples were constructed by iteration of the bifurcation unit. The mold method of constructing vascular scaffolds embedded within the bionic channels was proposed. The scaffold material is PDMS, and the surface was coated with collagen. The Human Umbilical Vein Endothelial Cells (HUVECs) were planted into the lumen of the channels for 7 days in vitro and found to be able to proliferate. The cells cultured for three days were fluorescently stained, and it was found that the cells were well attached to the surfaces of the lumen. This vascular design and fabrication process can lay a foundation for vascularization in bone tissue engineering.

We investigate the surface modification by laser texturing and effects thereof on the tribological performance in

Vascularization is one of the most important factors greatly influencing scaffold regeneration. In this study, a precise network of hollow vessels was printed by digital light processing (DLP) with poly(ethylene glycol) diacrylate (PEGDA)/gelatin-methacryloyl (GelMA), and dark pigmentation absorbers were added to ensure printing accuracy. First, the compound bio-inks of the PEGDA-GelMA hydrogel were prepared for direct vascular printing, and a high-precision DLP system was established. Second, the printing effects of three dark absorbers, namely, nigrosin, brilliant black, and brilliant blue, on the x-, y-, and z-axes were studied. By printing models with different densities, it was determined that 0.2% nigrosin, 0.1% brilliant black, and 0.3% brilliant blue had better effects on the x- and y-axes accuracy, and the absorbance of the absorbers played a decisive role in adjusting the accuracy. Additionally, to solve the problem of uneven curing on the upper and lower surfaces caused by the addition of an absorber with high absorbance, a model of the difference in curing width between the upper and lower surfaces of a unit-layer slice based on high-absorbance absorbers was established, and the reference value for the slice thickness was calculated. Third, the biological and mechanical properties of the bio-inks were verified with scanning electron microscopy and Fourier transform infrared, and by tensile, swelling, degradation, and cytotoxicity tests on different concentrations of PEGDA-GelMA hydrogel and absorbers. The results showed that 30% PEGDA-7% GelMA/0.1% brilliant black was the optimal preparation to print a hollow vascular network. The error of the printing tube wall and cavity was between 1% and 3%, which demonstrates the high precision of the method. Human umbilical vein endothelial cells were planted in the lumen, and the survival rate achieved 107% on the seventh day, demonstrating the good biocompatibility of the composite hydrogel.

The life of ceramic tools restricts the development of the manufacturing industry and can be increased through the enhancement of surface performance. Laser surface texturing is a feasible technology to improve ceramic tool life based on the relationship between surface properties and the laser-texturing process. In this study, ${{\rm Al}_2}{{\rm O}_3}$ substrates have been textured by an ytterbium fiber laser system with a wavelength of 1064 nm and a pulse duration of 50 ns. First, the damage threshold of ${{\rm Al}_2}{{\rm O}_3}$ was measured to provide a basis for selecting laser-texturing parameters. The surface morphology was characterized using a white confocal scanning microscope and a scanning electron microscope to investigate the characteristics of laser processing. Water contact angles were measured to investigate the relationship between laser parameters and changes in wettability. The surface energy of the superhydrophobic ceramic was calculated based on the contact angle. Combined X-ray photoelectron spectroscopy (XPS) measurement was used to explore the mechanism of wettability changes from the chemical component and microstructure perspectives. The friction coefficient of ${{\rm Al}_2}{{\rm O}_3}$ was determined by a ball-on-disc wear test. The results showed that laser texturing can significantly improve the surface hydrophobicity and friction stability.

Chemokine (C‑C motif) ligand 18 (CCL18) is derived from breast tumor‑associated macrophages (TAMs), which are primarily a macrophage subpopulation with an M2 phenotype. CCL18 binds to its receptor, PYK2 N‑terminal domain interacting receptor 1 (Nir1), and promotes tumor progression and metastasis by inducing epithelial‑mesenchymal transition (EMT) via the PI3K/Akt/GSK3β/Snail signaling pathway in breast cancer cells. Recent research shows that Annexin A2 (AnxA2) plays a significant role in the invasion, metastasis, angiogenesis, proliferation, F‑actin polymerization and multidrug resistance to chemotherapy of breast cancer. The present study aimed to elucidate the molecular mechanisms by which CCL18 promotes breast cancer progression through AnxA2 which are not fully understood. Western blot analysis showed that the expression of AnxA2 was upregulated in highly invasive breast cancer cell lines and invasive ductal carcinoma. Furthermore, through chemotaxis, scratch, Matrigel invasion, and spontaneous metastasis assays, it was demonstrated that AnxA2 enhanced the invasion of breast cancer cells and the metastasis of human breast cancer cells to lungs of SCID mice with CCL18 stimulation. Cellular F‑actin measurement assay showed that reduction of AnxA2 suppressed CCL18‑induced F‑actin polymerization though phosphorylation of integrin β1 in breast cancer cells. Immunofluorescence and western blot analysis revealed that AnxA2 promoted CCL18‑induced EMT via the PI3K/Akt/GSK3β/Snail signaling pathway, and LY294002 inhibited the phosphorylation of AnxA2 in vitro. In brief, AnxA2, as a downstream molecule of Nir 1 binding to CCL18, promotes invasion and metastasis by EMT through the PI3K/Akt/GSK3β/Snail signaling pathway in breast cancer. This study suggests that AnxA2 is a potential anti‑invasion/metastasis target for therapeutic intervention in breast cancer.

We investigate the surface modification by laser texturing and effects thereof on the tribological performance in A l 2 O 3 . By detailed observation for microstructure evolution, it has been shown that there were three distinct modification morphologies by laser treatment: dense surface microfeatures, “coral” dendritic structures, and coarse grains. X-ray diffraction (XRD) results indicated that there was no formation of metastable phases due to low supercooling in solidification in the nanosecond laser regime. The formation of AlN compounds in the laser-treated region was examined by using x-ray photoelectron spectroscopy (XPS), which led to dense surface microfeatures and randomly distributed pores formation in the laser treated region. The formation of “coral” dendritic structures on the edge of groove and coarse grains in the vicinity of the laser surface was attributed to the fast-cooling rates. Wear tests were carried out to analyze the effect of laser texturing on tribological performance. The results of coefficients of friction (COF) illustrated that laser texturing can significantly improve COFs for dry friction; however, it decreases the COFs for wet friction. The mechanism of wear was explained based on a SEM measurement for worn surfaces; the formation of surface texture can store abrasive particles and debris lead to hydrodynamic lubricant film formation and the COFs significantly reducing for wet friction.

Eight unknown impurities in xinfujunsu and its injection were characterized by liquid chromatography coupled with ion trap/time-of-flight mass spectrometry (LC-IT-TOF MS). In order to determine the m/z values of the molecular ions and predict the formulas of all detected impurities, full scan LC-MS in positive ion mode was firstly executed to obtain the m/z value of the molecules. Then LC-MS2, LC-MS3 and LC-MS4 were carried out on target compounds to obtain as much structural information as possible. Based on MSn spectral data and exact mass measurements, the chemical structures of eight unknown impurities were characterized, among which three impurities were degradation impurities and five impurities were process impurities. In addition, the source of impurities and the correlation between process and impurities were also studied. The production of degraded impurities was caused in the high pressure sterilization process of xinfujunsu injection. Based on characterization of impurities, this study revealed the cause of impurity production and provided guidance for enterprises to improve the process to reduce impurity content. Furthermore, this study also provided scientific basis for the further improvement of official monographs in pharmacopoeias.

The life of ceramic tools restricts the development of the manufacturing industry and can be increased through the enhancement of surface performance. Laser surface texturing is a feasible technology to improve ceramic tool life based on the relationship between surface properties and the laser-texturing process. In this study, A l 2 O 3 substrates have been textured by an ytterbium fiber laser system with a wavelength of 1064 nm and a pulse duration of 50 ns. First, the damage threshold of A l 2 O 3 was measured to provide a basis for selecting laser-texturing parameters. The surface morphology was characterized using a white confocal scanning microscope and a scanning electron microscope to investigate the characteristics of laser processing. Water contact angles were measured to investigate the relationship between laser parameters and changes in wettability. The surface energy of the superhydrophobic ceramic was calculated based on the contact angle. Combined X-ray photoelectron spectroscopy (XPS) measurement was used to explore the mechanism of wettability changes from the chemical component and microstructure perspectives. The friction coefficient of A l 2 O 3 was determined by a ball-on-disc wear test. The results showed that laser texturing can significantly improve the surface hydrophobicity and friction stability.

National Science Foundation of China (No. 21405005, 21501006) ; Joint Fund for Fostering Talents of National Natural Science Foundation of China and Henan Province (No. U1404208) ; Program for Science and Technology Innovation Talents at the University of Henan Province (17HASTIT001) ; Scientific Research Foundation for Returned Overseas Chinese Scholars, State Education Ministry.

As a new gear processing technology, gear slicing technology has the characteristics of high efficiency, high precision and environmental protection. In this paper, the slicing process with equal-rake angle arc-tooth slice tool (ERA-ATST) is taken as the research object. Considering the particularity of the slicing process, a theoretical calculation method of tool and chip temperature is proposed. By analyzing the characteristics of the slicing process with ERA-ATST, a cutter tooth of the ERA-ATST is divided into several sections along the cutting edge, which are called micro-section tooth. For each of the micro-section tooth, the slicing process is simplified and equivalent to oblique cutting process. Comprehensively considering the influence of cutting speed, chip force and tool-chip contacting characteristics in slicing process, a temperature calculation model is established based on the generation mechanism of slicing heat. The tool and chip temperature is derived by averaging the results of several micro-section teeth. With the established model, an inner arc-spur gear slicing with the ERA-ATST is used as an example to calculate the temperature on the chip and rake face. The gear slicing test is carried out on the slicing machine tool. The measured chip temperature and rake face temperature are compared with the corresponding calculation results to verify the temperature calculation model. The proposed temperature calculation method provides a theoretical basis for the analysis and control of slicing heat in the gear slicing process.

This paper presents an investigation of wettability of zirconia by nanosecond laser treatment. Laser treatment of zirconia has been carried out for investigating the surface wettability with different processing parameters. Morphological and metallurgical modifications are examined in the laser treated layer by using scanning electron microscope (SEM) and X-ray photoelectron spectroscopy (XPS). The contact angle (CA) and surface roughness also have been measured. It is found that the micro pits and cracks is produced, and the melt of material is splashed on the surface of untreated surface, forming irregular bumps during laser processing, the surface morphology become more complex than the expected surface structure. The dependency of water contact angle of surface by laser treated with time is attributed to the modification of surface chemical composition, especially the change of carbon content and oxygen content. Surface roughness is a factor affecting the stable contact angle.

A post-and-core crown is widely used in prosthetic dentistry; however, in clinical treatment, it easily causes root fracture and tooth penetration. To address these problems, this study aimed to present a customized post-and-core design for the posterior tooth implant. First, a residual tooth and its root canal were reconstructed. Then, the root canal surface was extracted, the surface curvature and length parameters were defined, and the customized post-and-core design was developed. Finally, the tooth, root canal, and post-and-core with different implant lengths in five masticatory directions were analyzed using finite element analysis to evaluate the stress distribution. The results showed that, with the similar shape of the post-and-core structure and the root canal, the tooth stress trend was uniform. When the length of the post-and-core structure [Formula: see text] was 0[Formula: see text]mm, that is, it was two thirds of the root canal length, the root canal stress was minimum. Therefore, the customized design of the post-and-core structure could well adapt to any kind of root canal, and the length of the post-and-core structure [Formula: see text] provided guidance for the post-and-core crown prosthesis in clinic.

In human skull tissue engineering scaffolds, cell growth and osteogenesis are limited due to the lack of vascular structure. Therefore, a mosaic structure vascular parameterized design method is proposed according to the scanning characteristics of the diploic vein. Using micro-CT scans of skull samples, the features of the diploic vein were extracted, and a multi-level vascular network model was established based on a power diagram. Considering the characteristics of blood flow in the veins, finite element analysis (FEA) of the fluid-solid coupling was established to analyze the effect of blood on vessels with four-level mosaic structures. The results showed that the deformation and stress distribution of vessels were reasonable, and the blood pressure, velocity and shear stress in the designed vascular structure could meet the cell growth requirements. The mosaic structure was prepared by PDMS and cultured in vitro using HUVECs. It was found that most of the cells survived after 48 h, and some cells were attached to the surface mosaic structure. In this method, different levels of vessels nest together, with a curvature that matches the shape of the skull, forming a similar morphology to the native diploic vein, and the local structures can be adjusted flexibly. This mosaic structure vascular design method can be used for network vascular design and experimental studies in hard tissues.

During the second Chinese National Arctic Research Expedition in summer 2003, sea ice cores and the underlying water were sampled from seven stations in the pack ice zone of the Canada Basin and were examined with a phase contrast microscope. A total of 102 and 78 algal species were identified for the ice cores and the underlying water, respectively, ranking in the middle range among the surveys of the Arctic Ocean up to the present despite seasonal variability. The Shannon-Wiener indices ranged from 1.40 to 4.88 with an average of 3.58 ± 0.68. Diatom species, especially pennate species, dominated in all the samples. A large number of algal spores were contained in every layer (abundance percentage > 1%). The microalgal abundances ranged from 1.4 × 104 to 8.73 × 105 cells L−1 and the biomass ranged from 0.56 to 89.49 μg L−1. They were correlated with the number of algal species (P < 0.05) but not with the diversity index (P > 0.05). Ice algal maxima were observed in various layers (bottom, interior and near the surface of the ice floes). The phytoplankton biomass in the ice-water interface was one order of magnitude lower than that in the bottom ice (P < 0.05). The species number and the diversity index in water samples, with much less biomass (P < 0.01), were comparative with the ice samples (P > 0.05). Spatial heterogeneity in both horizontal and vertical directions was the main characteristic of the algal community structure, which was demonstrated by the cluster analysis result and the distribution patterns.

Aims This research aimed to examine the relationship between Dock1 and miR-31 and to determine the effect of miR-31 on the mesenchymal transition and invasiveness of glioma. Methods Real-time PCR was used to measure the expression of miR-31 and other RNAs. The transfection was used to manipulate the expression levels of Dock1 and miR-31 in cancer cells. Western blot was used to detect the expression of Dock1 and other related proteins. Wound healing, Matrigel invasion and chemotaxis assays were performed to detect the invasion and migration of glioma cell lines. The actual binding site of miR-31 to the 3′-untranslated region of Dock1 was confirmed through luciferase assay and RNA immunoprecipitation. Methylation-specific PCR was performed to detect the methylation level of miR-31 in both glioma cell lines and tissues. Results Dock1 can promote the IL8-induced chemotaxis and mesenchymal transition of glioma cells through the NF-κB/Snail signalling pathway. The protein levels of Dock1 in glioma cell lines and clinical specimens were negatively correlated with miR-31 expression, and Dock1 was directly targeted by miR-31. Animal experiments showed that Dock1 downregulation and miR-31 overexpression reduced glioma cell invasion. Investigation of the underlying molecular mechanism revealed that miR-31 downregulation was attributable to the hypermethylation of the promoter region of miR-31 in glioma cells. Conclusion Dock1 modulation by miR-31 plays an important function in glioma invasion both in vitro and in vivo. This study provides new insights into the invasion of glioma cells and might therefore contribute to the development of new antiglioma strategies.

For the limits of the symmetrical structure and uncontrollability in current cranial microstructure modeling, a biomimetic modeling approach based on micro-CT technology is proposed in this paper. At the beginning, the natural cranial sample is scanned by micro-CT technology and reconstructed using reverse engineering. Then through the study of the reconstructed sample, it is found that the cranial microstructure is configured by three parts of special architecture nets, cavity and connecting pipe. So after the parametric analysis, modeling to the three parts respectively, and assembly them in a certain form, the partial biomimetic model of the cranial microstructure was established. The results indicate that the biomimetic model and the natural cranial microstructure show high similarity.