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Tympanic membrane (TM) perforation leads to persistent otitis media, conductive deafness, and affects life quality. Ointment medication may not be sufficient to treat TM perforation (TMP) due to the lack of an underlying tissue matrix and thus requiring a scaffold-based application. The engineering of scaffold biointerface close to the matrix via tissue-specific decellularized extracellular matrix (dECM) is crucial in instructing cell behaviour and regulating cell-material interaction in the bioengineering domain. Herein, polycaprolactone (PCL) and TM-dECM (from Sprague–Dawley rats) were combined in a different ratio in nanofibrous form using an electrospinning process and crosslinked via tannic acid. The histological and biochemical assays demonstrated that chemical and enzymatic decellularization steps removed cellular/immunogenic contents while retaining collagen and glycosaminoglycan. The morphological, physicochemical, thermomechanical, contact angle, and surface chemical studies demonstrated that the tannin crosslinked PCL/dECM nanofibers fine-tune biophysical and biochemical properties. The multifaceted crosslinked nanofibers hold the tunable distribution of dECM moieties, assembled into a spool-shaped membrane, and could easily insert into perforated sites. The dECM decorated fibers provide a preferable biomimetic matrix for L929 fibroblast adhesion, proliferation, matrix adsorption, and f-actin saturation, which could be crucial for bioengineering. Overall, dECM patterning, surface hydrophilicity, interconnected microporosities, and multifaceted nanofibrous biosystem modulate cell–scaffold performance and could open opportunities to reconstruct TMP in a biomimetic fashion.

Dual phase grating x-ray interferometry is compatible with common imaging detectors, and abandons the use of an absorption analyzer grating to reduce the radiation dose. When using x-ray tubes, an absorbing source grating must be introduced into the dual phase grating interferometer. In order to attain a high fringe visibility, in this work we conduct a quantitative coherence analysis of dual phase grating interferometry to find how the source grating affects the fringe visibility. Theoretical analysis shows that with the generalized Lau condition satisfied, the fringe visibility is influenced by the duty cycle of the source grating and the transmission through the grating bar. And the influence of the source grating profile on the fringe visibility is independent of the phase grating type. Numerical results illustrate that the maximum achievable fringe visibility decreases significantly with increasing transmission in the grating bar. Under a given transmission, one can always find an optimal duty cycle to maximize the fringe visibility. These results can be used as general guidelines for designing and optimizing dual phase grating x-ray interferometers for potential applications.

We present a moment-based alternative approach to retrieve multiple scattering contrasts from x-ray analyzer-based imaging. By use of the properties of moments of convolutions, the multiple-image radiography approach is theoretically validated. Furthermore, higher order moments of the object scattering distribution, inaccessible in multiple-image radiography, are simultaneously provided by this alternative approach. It is experimentally demonstrated that the skew and kurtosis information related to the distribution of sub-pixel features within the object can be obtained from those complementary contrasts. Finally, the sensitivity of the retrieved multiple scattering contrasts is investigated experimentally. The finding that the sensitivity is inversely proportional to the square root of the detected photon number essentially indicates that the retrieval of moments with an order higher than two can be achieved without increasing exposure time or dose. The presented alternative approach provides an access to the exploitation of multiple scattering contrasts, which is expected to be useful in biomedical research, materials science, security screening, etc.

Recently, a novel three-image algorithm has been proposed to retrieve the sample’s absorption, refraction, and scattering properties in x-ray analyzer-based imaging. The feasibility of the three-image algorithm was validated by synchrotron radiation experiments. However, it is unclear yet whether the estimated refraction and scattering signals are biased or not and how the analyzer angular position affects the biases in the estimated signals. For this purpose, the biases of the extracted refraction and scattering signals are theoretically derived for the three-image algorithm. The theoretical models are further confirmed by numerical experiments. The results show that both the estimated refraction and scattering signals are biased, and the biases are strongly dependent on the analyzer angular position. Besides, the biases also show dependence on the sample’s refraction and scattering properties locally. Those results can be used as general guidelines to optimize experimental parameters for bias reduction and accurate imaging of different features within the sample.

With the obvious improvement in people’s quality of life, the use of natural gas is becoming increasingly common. Household natural gas has hidden safety hazards while being hygienic and convenient. There are many gas explosion accidents every year, and life and property are seriously damaged. When the natural gas body leaks a little and the methane concentration in the air is extremely low, the methane sensor may fail to report, and the signal is weak or the early warning signal cannot be processed in time, which brings hidden dangers to the accident of gas explosion. In this paper, an optimized array of antenna arrays is designed based on the ZigBee network. Use multiple MQ-4 sensor arrays to detect the methane concentration in the kitchen, and send the weak signals collected by the four methane sensors to the ZigBee router in the same direction through the four antennas of the ZigBee module. The router timely and accurately transmits to the ZigBee coordinator and uses ZigBee network technology to upload the alarm information to the cell monitoring center through wireless. The simulation test results show that the diamond antenna array can quickly detect the change of methane concentration, and has high sensitivity and reliability.

Named entity recognition (NER) is a common task in Natural Language Processing (NLP). To this end, we propose a novel approach based on pre-training model to complete the sequence labeling tasks by learning the large-scale real-world data from Brazilian legal documents. Especially, combining iterated dilated convolution[1] (IDCNN) and Bi-LSTM, we develop the scalable sequence labeling model named Sequence Tagging Model (STM) and extensive experiments validate the effectiveness of STM for NER tasks. Furthermore, compared with the IDCNN-CRF model, the experimental results show that the STM is better and the F1 score is 93.23%, which provides an important basis for NER tasks.

Driving behavior is one of the most important reasons that affect traffic safety and energy saving. In view of the management problems existing in traffic safety, it is necessary to strengthen the driver’s safety and energy conservation awareness. To this end, based on the driving status information collected by the road transportation industry in the vehicle networking system, we propose a data-driven approach to dig deeper into driving behaviors that affect driving safety and energy efficiency. Among them, we used the quantitative description of idle speed preheating, overspeed, fatigue driving and other series of indicators, and combined with the AHP (Analytic Hierarchy Process) to construct a comprehensive driving safety evaluation index system. Assisting the Ministry of Transportation in managing roads more efficiently and creating a harmonious driving environment via our evaluation model.

Social change has a direct influence on the family loss. To this end, we propose a novel approach to model the probability of family loss by learning the large-scale real-world survey data from China Family Panel Studies (CFPS). Especially, combining individual economic, health, identity, family profile and other information, we develop the scalable tree boosting model named Family Loss Prediction Model (FLPM) to model the family loss. Extensive experiments on real-world survey data validate the effectiveness of FLPM for measuring the probability of family loss in China. Furthermore, compared with the XGBoost and GBDT models, the experimental results show that the FLPM model is better and the precision is 98.48%, which provides an important basis for this study.

We develop an element-specific x-ray microscopy method by using Zernike phase contrast imaging near absorption edges, where a real part of refractive index changes abruptly. In this method two phase contrast images are subtracted to obtain the target element: one is at the absorption edge of the target element and the other is near the absorption edge. The x-ray exposure required by this method is expected to be significantly lower than that of conventional absorption-based x-ray elemental imaging methods. Numerical calculations confirm the advantages of this highly efficient imaging method.

X-ray grating interferometry provides substantially increased contrast over conventional absorption-based imaging methods, and therefore new and complementary information. Compared with other phase-contrast imaging techniques, x-ray grating interferometry can overcome some of the problems that have impaired the applications of x-ray phase-contrast radiography and phase tomography. Recently, special attention has been paid to the development of quantitative phase retrieval methods, which is mandatory to perform x-ray phase tomography, to achieve material identification, to differentiate distinct tissues, etc. Typically, the phase-stepping approach has been utilized for phase retrieval in grating interferometry. This method requires a grating scanning and acquisition of multiple radiographic projections, and therefore is disadvantageous in terms of imaging speed and radiation damage. Here we present an innovative, highly sensitive approach, dubbed 'reverse projection' (RP), for quantitative phase retrieval. Compared with the phase-stepping approach, the present RP method abandons grating scanning completely, and thus is advantageous due to its much higher efficiency and the reduced radiation dose, without the degradation of reconstruction quality. This review presents a detailed explanation of the principle of the RP method. Both radiography and phase tomography experiments are performed to validate the RP method. We believe that this new technique will find widespread applications in biomedical imaging and in vivo studies.

We propose a method for reconstructing a complex field from a series of its near-field diffraction patterns. This method is based on the paraxial Fresnel diffraction equation without making further approximations. Numerical simulations are presented showing that a complex field can even be reconstructed with moderate qualities from its two near-field diffraction patterns and almost exact reconstructions can be obtained when three or more diffraction patterns are used. We also show by numerical simulation that the correct diffraction distances can be recovered in case only coarsely measured values are available. This method may be applied to phase imaging of weak-absorption objects.

This paper presents an integrated delta-sigma digital current sensor. With high sensitivity and good linearity, GMR sensor is a good choice for current measurement application. In this design, a GMR sensor which is configured as a Wheatstone bridge of four spin-valve sensing elements is integrated with CMOS signal processing circuit together, and the output signal is converted to digital domain by an on-chip 10-bit delta-sigma ADC. The whole circuit is designed and simulated using CSMC standard 0.5 μm process.