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Pregnancy complications affect millions of women each year. Some of these diseases have high morbidity and mortality such as preeclampsia. At present, there is no safe and effective treatment for pregnancy complications, so it is still a difficult clinical problem. As many pregnancy complications are closely related to placental dysplasia, placenta-specific therapy, as an important method, is expected to be a safe, effective, and specific therapeutic strategy. This review explains in detail the placenta physiological structure, characteristics, and action mechanism of some biomolecules and signaling pathways that play roles in normal development and disorders of the development of the placenta, and how to use these biomolecules as therapeutic targets when the placenta disorder causes disease, combining the latest progress in the field of nanodelivery systems, so as to lay a foundation for the development of placenta-specific therapy of pregnancy complications.

With the continuous improvement in medical science in modern times, the spread of bacterial infection has become a matter of global concern. Therefore, the search for biological medical materials with antibacterial function has become a focus of intense research. In this work, pure SnO2 and Ag-doped SnO2 hollow nanofibers were fabricated by a combination of an electrospinning method and a calcination procedure, and the effects of the doped Ag on antibacterial activity and catalytic antibacterial activity were subsequently investigated. Through the process of high-temperature calcination, a high heating rate would lead to the formation of a hollow tubular structure in SnO2 fibers, and Ag2O would be reduced to Ag0 by a facile process with appropriate thermal treatment. Additionally, the existence of SnO2 as a tetragonal rutile structure was confirmed. On the basis of pure SnO2, doping with Ag greatly improved the antibacterial activity and catalytic antibacterial activity of hollow nanofibers. The formation mechanism and the antibacterial mechanism of pure SnO2 and Ag-doped hollow nanofibers are also discussed. This study has broad application prospects for biological medicine.

Multi-wall Sn/SnO2 @carbon hollow nanofibers evolved from SnO2 nanofibers are designed and programable synthesized by electrospinning, polypyrrole coating, and annealing reduction. The synthesized hollow nanofibers have a special wire-in-double-wall-tube structure with larger specific surface area and abundant inner spaces, which can provide effective contacting area of electrolyte with electrode materials and more active sites for redox reaction. It shows excellent cycling stability by virtue of effectively alleviating pulverization of tin-based electrode materials caused by volume expansion. Even after 2000 cycles, the wire-in-double-wall-tube Sn/SnO2 @carbon nanofibers exhibit a high specific capacity of 986.3 mAh g-1 (1 A g-1 ) and still maintains 508.2 mAh g-1 at high current density of 5 A g-1 . This outstanding electrochemical performance suggests the multi-wall Sn/SnO2 @ carbon hollow nanofibers are great promising for high performance energy storage systems.

In order to solve the problem of low detection accuracy of small targets in the SSD detection algorithm, a pipeline magnetic flux leakage image detection algorithm based on multiscale SSD network is proposed in this paper. The dilated convolution and attention residual module are introduced into the SSD algorithm to fuse the low-resolution high-semantic information feature map with the high-resolution low-semantic information feature map so as to improve the resolution of the low-resolution feature map and provide detailed features for small targets. Finally, the target location and category are obtained by regression algorithm. The experimental results show that the proposed algorithm can automatically identify the location of circumferential weld, spiral weld, and defect of magnetic flux leakage data. Compared with the original SSD algorithm framework, the improved algorithm has higher detection accuracy, 97.62%, 18.01% lower false detection rate, 18.36% lower false detection rate, better robustness, and obvious effect on small target detection.

Hierarchically structured nanomaterials are critical for the catalysis and energy storage to make full use of the surfaces and space to elevate activities. Electrospinning is a very convenient technique for programmable fabrication of different kinds of nanofibers with diverse compositions as well as complex internal and external structures for various demands in application of catalysis and energy storage fields. In this review, some effective electrospinning strategies for constructing various nanofibrous materials with multilevel structures are presented. Firstly, hierarchically hollow structured nanofibers are described and categorized including hollow fibers, wire-in-tube fibers, tube-in-tube fibers, peapod-like fibers, multichannel fibers and outer branched fibers etc. The unique properties arose from the special hierarchical structures effect such as multiple heterogeneous interfaces, confined space and large specific area are discussed and some representative applications in catalysis and energy storage are presented. Finally, the challenges and perspectives of future researches on the electrospinning hierarchically structured nanofibers for various applications are highlighted.

The approaches for cotton shrink-resistant finishing can be categorized into chemical finishing and physical finishing. In this research, a new approach to prevent cotton fabric from shrinkage and wrinkling without resin finishing was studied to reach an easy care effect of “wash-and-wear” for related end products. It was achieved by adding a certain proportion of fine denier polyester and memory polyester fibers. Unlike the previous chemical finishing methods, this physical finishing method does not cause yellowing, formaldehyde content increase or strong damage of tensile strength. It can reduce the shrinkage rate and increases the wrinkle recovery angle (WRA) through the shape memory formed by the memory polyester fiber in the heat setting stage. Our results were of better condition with significant improvements in WRA, anti-pilling effect, shrink-proofing and strength of the fabrics. The fabrics can be widely used in bedding textiles and shirting fabrics.

Multi-wall Sn/SnO

In order to solve simultaneous multi-leak problem of the pipeline, a method to detect multi-leak of pipeline by using optical fiber detection technology is proposed. Firstly, use optical fiber sensors to detect pressure signal, then construct the residual generator based on the fault diagnosis observer, and the leak coefficients are extracted by the residual error. Secondly, make the observer has good robustness to the unknown input disturbance by using the decoupling technology for disturbance. Stability of the fault diagnosis observer is proven by using the Lyapunov function and Barbalat lemma. The approach can detect and estimate the leak coefficients. Experiment results show that the effectiveness of the propsed approach.

The paper demonstrates the relationship between a local stress concentration state and the self magnetic leakage field (SMLF) measured by the metal magnetic memory (MMM) effect using a first-principle calculation based on the density functional theory (DFT). In order to verify the theoretical approach, blasting experiments with X70 steel pipes were performed to document the reliability of the investigation methods. Interestingly concerning the theoretical approach is the linear change of the local SMLF signal with the increase of stress which is in very good agreement with the experimental observations. A new research program for quantitative interpretation of the MMM effect was initiated.

Communication on power line is a useful means. An intelligent control system-on-chip RISE3201 is adopted to realize low-voltage power line modem. It is a carrier spread spectrum system that includes RISE3201 and external circuits such as coupling circuit, send-receiver circuit. Upon this system, two anti-jamming method CRC code and hamming code are used to improve communication quality. Some experiments had been done under various distances and different time. The results show that the serial communication error code is greatly eliminated with using CRC code and hamming code. These methods are suitable for serial communication over low-voltage power line.

In magnetic flux leakage (MFL) testing of pipelines, quantitatively classifying defects remains to be a difficult problem. The mathematical model of MFL field is presented based on the finite element (FE) method, and two-dimensional axisymmetric FE model of MFL testing system is also established by adopting ANSYS software to simulate magnetostatics. The results show that different defects cause different signal. There are certain functions between the defect character and MFL signal character. Defect is quantitatively classified by MFL signal character.

A pipeline MFL (magnetic flux leakage) inspection device with high resolution generates a great deal of data, so it is necessary to compress the real-time data. The characteristics of MFL inspection data was analyzed, the inspection data was preprocessed to eliminate the effect of sensor lift-off and the preprocessed MFL image was segmented to ensure the ROI (region of interest). Integer wavelet transform was applied to the ROI and wavelet coefficient which was lifted by the max shift method and combined with SPIHT (set partitioning in hierarchical tree) code algorithm realizes the lossless compression of MFL image ROI and compression ratio is over 8:1

Aiming to the low accuracy IMU's initial alignment issue related to the pipeline's geographical coordinate measuring system (PGC), the PGC initial alignment method is introduced. The coarse alignment is used to resolve large angle error at first, and then the precise alignment is done in small angle range. In the precise alignment process, the irstorder Markov process is used to separate the white noise, then the 13 dimension states equation and the measuring equation are built; the unscented particle kalman filtering (UPF) is used to resolve nonlinear problem that caused by the large attitude angle. The experiment shows that the method mentioned above can effectively mproves the accuracy of the initial alignment in the PGC.