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Peripheral nerve injury (PNI) is a common and complex clinical disease with high morbidity, limited treatment options and poor clinical outcomes. Several million cases of PNI in the world every year have brought a heavy burden to the patients and the social economy. Autologous nerve grafting has long been the "gold standard" in the treatment of PNI repair, but it still has some shortcomings, such as donor area injury, limited graft source and mismatch of nerve thickness after transplantation. In recent years, many artificial nerve guidance conduits (NGCs) have emerged for replacing autologous nerve grafts, and their effectiveness has been proven. Currently, there are already clinical products obtained from the European CE Certification, and approved by the Food and Drug Administration (FDA), China Food and Drug Administration (CFDA), Therapeutic Goods Administration (TGA) in Australia, etc. The preparation of NGCs requires interdisciplinary studies and has received considerable attention from researchers in recent years. At present, among emerging and mature manufacturing technologies, textile methods to prepare NGCs are relatively simple and have wide material sources, which has become a hotspot in textile research. This paper mainly reviewed the current situation and recent technological achievements of NGCs that were prepared by textile methods. Several other common methods were also briefly summarized. Furthermore, current NGCs products and their clinical applications were reported. Finally, the future development direction of textile-based NGCs is discussed in this review. [ABSTRACT FROM AUTHOR]

Wheat gluten (WG) foam was successfully prepared by heating, stirring and freeze-drying. The effects of WG concentration, content of glycerol and glutaraldehyde on the macroscopic appearance, microstructure, swelling property and self-expansion, as well as mechanical compressibility, were studied. Results showed that the density and structure of foam can be changed by adjusting the concentration of WG, glycerol, and glutaraldehyde. The addition of glycerol softens the WG foams, while glutaraldehyde significantly improved their mechanical properties and stability in wet state. The swollen foams were repeatedly pressed and exhibited rapid water-triggered shape recovery performance (less than 3 s). Moreover, WG foams displayed excellent biodegradability and hemocompatibility. In vitro studies of drug loading and release were performed using an antibacterial drug, chlorhexidine gluconate (CHG), and showed sustained drug-release activity. The above advantages make the foams hold great potential for application in self-expanding, antibacterial hemostatic medical dressings. [ABSTRACT FROM AUTHOR]

Synchrotron radiation real-time imaging technology was carried out in situ to observe and characterize the effect of thermomigration on the growth behavior of interfacial intermetallic compounds (IMCs) in Cu/Sn/Cu solder joint during soldering. The thermomigration resulted in asymmetrical formation and growth of the interfacial IMCs. Cu6Sn5 and Cu3Sn IMCs formed at the cold end and grew rapidly during the whole soldering process. However, only Cu6Sn5 IMC formed at the hot end and remained relatively thin until solidification. The IMCs at the cold end were nearly seven times thicker than that at the hot end after solidification. The Cu dissolution at the cold end was significantly restrained, while that at the hot end was promoted, which supplied Cu atoms to diffuse toward the cold end under thermomigration to feed the rapid IMC growth. Moreover, the thermomigration also caused asymmetrical morphology of the interfacial IMCs at the cooling stage, i.e., the Cu6Sn5 IMC at the cold end transformed into facet structure, while that at the hot end remained scallop-type. The asymmetrical growth behavior of the interfacial IMCs was analyzed from the view point of kinetics. [ABSTRACT FROM AUTHOR]

Background/aims: Sheep are important livestock with variant ovulation rate and fertility. Dorset sheep is a typical breed with low prolificacy, whereas Small Tail Han sheep with FecB mutation (HanBB) have hyperprolificacy. Our previous studies have revealed the gene expression difference between the ovaries from Dorset and HanBB sheep contributes to the difference of fecundity, however, what leads to these gene expression difference remains unclear. DNA methylation, an important epigenetic process, plays a crucial role in gene expression regulation. Methods: In the present study, we constructed a methylated DNA immunoprecipitation combined with high throughput sequencing (MeDIP-seq) strategy to investigate the differentially methylated genes between the Dorset and HanBB ovaries. Results: Our findings suggest the genes involved in immune response, branched-chain amino acid metabolism, cell growth and cell junction were differentially methylated in or around the gene body regions. Conclusions: These findings provide prospective insights on the epigenetic basis of sheep fecundity. [ABSTRACT FROM AUTHOR]

In our previous study, we investigated the regulatory relationship between lncRNAs, miRNA, and mRNAs in an effort to shed light onto the regulatory mechanisms involved in sheep fecundity. As an extension of this study, here, we aimed to identify potential regulators of sheep fecundity using a genome-wide analysis of miRNAs and the methylated genes encoding mRNAs and lncRNAs in the ovaries of Dorset sheep (low fecundity) and Small Tail Han ewes (high fecundity) with the genotype BB (Han BB) and the genotype ++ (Han ++) by performing RNA-Seq and MeDIP-Seq analyses. Methylated coding-non-coding gene co-expression networks for Han and Dorset sheep were constructed using the methylated genes encoding the differentially expressed mRNAs and lncRNAs identified in this study. In the Han BB vs. Dorset comparison, the lncRNAs TTC26 and MYH15 had the largest degree. Similarly, the lncRNA NYAP1 had the largest degree in the Han ++ vs. Dorset comparison. None of the methylated genes encoding lncRNAs were co-expressed with the methylated genes encoding mRNAs in the Han BB vs. Han ++ comparison. The methylated genes encoding lncRNAs identified here may play a vital regulatory role in sheep breeding. Our results suggest that miRNAs might play a key role in sheep prolificacy by regulating target genes related to thyroid hormone synthesis, and methylated genes encoding lncRNAs associated with tight junctions might contribute to the high breeding rate in Han sheep. These findings may contribute to a deeper understanding of sheep prolificacy. [ABSTRACT FROM AUTHOR]

In this study, self-assembly regenerated silk fibroin (RSF) nanofibers were prepared and observed by Atomic Force Microscope (AFM). Then RSF films containing nanospheres and nanofibers were prepared and dissolved with poly (L-lactide-co-ε-caprolactone) (PLCL) with a blending ratio of 30/70 in hexafluoro-2-propanol (HFIP). In order to determine whether different nanostructures in the solution influence the morphological, structural, and mechanical properties of the final electrospun materials, flat membranes were prepared and characterized by Scanning Electron Microscope (SEM), Fourier Transform Infrared (FT-IR), and mechanical testing. The secondary structure of as-spun materials with RSF nanofibers were not changed, however, the diameter of electrospun fibers decreased and tensile strength and elongation at breaks increased. Electrospun materials with RSF nanofibers have the potential to be used for skin, cartilage, and blood vessels because of their biocompatibility and improved mechanical properties. [ABSTRACT FROM AUTHOR]

Silk fibroin (SF) hydrogels were obtained fromboth domestic (Bombyx mori) and wild (Antheraea pernyi) silkworms from aqueous silk fibroin solutions at room temperature. The gelation time of the Antheraea pernyi (A. pernyi) SF solution was significantly shorter than that of the Bombyx mori (B. mori) SF solution. The secondary structures of the two kinds of hydrogels were also compared. In order to further reduce the gelation time, various amounts of polyethylene glycol (PEG) were blended with the silk fibroins of A. pernyi and B. mori. The gelation time of both A. pernyi SF and B. mori SF decreased with the increased amount of PEG. After freeze-drying, the hydrogels were characterized through X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and Raman spectroscopy. Results showed that the addition of polyalcohol did not change the main secondary structure of the hydrogels. However, the addition of polyalcohol did reduce the gelation time and triggered additional formation of β-sheets. [ABSTRACT FROM AUTHOR]

Fatigue testing for twelve SG tubular fabrics with various textile parameters was performed under pulsatile pressure by an Accelerated fatigue tester. Two time points as of 0, and 1x108 cycles were selected. The percentage change of tubular diameter, fabric count, porosity, and water permeability before and after the fatigue testing were used to characterize the fatigue performance. Bursting work was used to indicate fatigue. The mathematical model of quantification theory I was used to analyze the influence of various textile parameters on the fatigue performance of SG tubular fabric. It was found that with the increase of fatigue time, bursting work decreased, and the predicting results by quantification theory I for the fatigue resistance were relatively accurate and the contribution ratio of each textile parameter to the fatigue performance was also obtained. Different textile parameter has different contribution ratio if different parameters were used to characterize the fatigue performance. Woven construction had more influence than yarn size on the fatigue performance, and yarn type had the least influence on it. Woven construction, yarn size, and yarn type had interactive influence on the fatigue performance. This can provide theoretical foundation for making better fatigue resistant SG tubular fabrics. [ABSTRACT FROM AUTHOR]

The Vehicle-borne Laser Measurement System (VLMS) is a mobile mapping system where three single-row laser range scanners, six line CCD cameras, and a GPS/INS-based navigation unit are mounted on a van to measure object geometry and texture along a street. This paper contributes to a method of fusing the data output of VLMS with existing geographic data sources where the focus is on the rectification of the vehicle's motion data derived from GPS/INS, which may be quite erroneous in an urban area. An algorithm is developed to correct the four variables of the vehicle's motion data, i.e., x, y, and z coordinates of the vehicle position and yaw angle of orientation by registering the laser points of the VLMS with an existing data source, e.g., a DSM. The algorithm was examined using the VLMS data that were taken in the Ginza District, Tokyo. By manually assigning 18 sets of tiepoints, the vehicle's motion data were corrected automatically and efficiently, such that the laser points of VLMS were matched to a DSM. In data fusion, a set of objects, which contained commercial signboards, traffic signs and signals, road boundaries, and road lights were extracted from the corrected VLMS data using an interface described in a previous paper. They were integrated with a 1:2500 3D map that consists of only building frames. In addition, line images from the VLMS were projected onto the building facades of the 3D map, and textures were generated automatically. [ABSTRACT FROM AUTHOR]

In this research, we propose a novel system for tracking pedestrians in a wide and open area, such as a shopping mall and exhibition hall, using a number of single-row laser-range scanners (LD-A), which have a profiling rate of 10 Hz and a scanning angle of 270°. LD-As are set directly on the floor doing horizontal scanning at an elevation of about 20 cm above the ground, so that horizontal cross sections of the surroundings, containing moving feet of pedestrians as well as still objects, are obtained in a rectangular coordinate system of real dimension. The data of moving feet are extracted through background subtraction by the client computers that control each LD-A, and sent to a server computer, where they are spatially and temporally integrated into a global coordinate system. A simplified pedestrian's walking model based on the typical appearance of moving feet is defined and a tracking method utilizing Kalman filter is developed to track pedestrian's trajectories. The system is evaluated through both real experiment and computer simulation. A real experiment is conducted in an exhibition hall, where three LD-As are used covering an area of about 60 × 60 m². Changes in visitors' flow during the whole exhibition day are analyzed, where in the peak hour, about 100 trajectories are extracted simultaneously. On the other hand, a computer simulation is conducted to quantitatively examine system performance with respect to different crowd density. [ABSTRACT FROM AUTHOR]

Focuses on a study which proposed a novel vehicle-borne system of measuring three-dimensional (3-D) urban data suing single-row laser range scanners. Alignment of the vertical range profiles; Kinds of techniques used for measuring 3-D geometrical data; Obstacles to acquire 3-D data of complicated environment with necessary accuracy and robustness.

There is a potentially strong demand for detailed 3D spatial data of urban areas. A ground-based laser range scanner is one of the promising devices to acquire range images of urban 3D objects. In this paper, the authors propose an automated registration method of multiple overlapping range images for the reconstruction of 3D urban objects. Registration is achieved in two steps, pair-wise registration and multiple registration as-suming that one rotating axis of a laser range scanner is almost vertical. At first, pair-wise registration determines the approximate values off our transformation parameters, a horizontal rotation angle and three translation parameters of a pair of neighboring range images. Then through multiple registration, the transformation parameters of all range images are adjusted using the approximate values so as to minimize the total errors. An outdoor experiment was conducted registering 42 range images to construct a 3D model of a building on the campus of the University of Tokyo. The accuracy of the model was examined using a 1:500scale digital map and GPS-measured locations of the viewpoints. The efficiency and accuracy of the registration method is demonstrated in this paper. [ABSTRACT FROM AUTHOR]

Braided silk fibroin tubes, the basic material of tubular tissue engineering vascular scaffolds, were designed in this study. Based on the characteristics of braided fabrics, a nonlinear model was established for predicting the stress-strain relationship. This model was proved to have high predicting precision for the similar materials through fitting analysis of the tested values, which could provide theoretical foundation to design coating layers for braided silk fibroin tubes to prevent blood leakage. [ABSTRACT FROM AUTHOR]