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The wide deployment of speech-based biometric systems usually demands high-performance speaker recognition algorithms. However, most of the prior works for speaker recognition either process the speech in the frequency domain or time domain, which may produce suboptimal results because both time and frequency domains are important for speaker recognition. In this paper, we attempt to analyze the speech signal in both time and frequency domains and propose the time-frequency network~(TFN) for speaker recognition by extracting and fusing the features in the two domains. Based on the recent advance of deep neural networks, we propose a convolution neural network to encode the raw speech waveform and the frequency spectrum into domain-specific features, which are then fused and transformed into a classification feature space for speaker recognition. Experimental results on the publicly available datasets TIMIT and LibriSpeech show that our framework is effective to combine the information in the two domains and performs better than the state-of-the-art methods for speaker recognition., Comment: 5pages, 3 figures

To establish a highly sensitive time-resolved fluorescence immunoassay (TRFIA) of kidney injury molecule-1 (Kim-1) and evaluate its clinical value in acute kidney injury (AKI).The Kim-1-TRFIA was established by the double-antibody sandwich method, and the method was evaluated. The established Kim-1-TRFIA was used to detect the concentration of Kim-1 in the serum of healthy controls and patients with AKI.The optimal coating antibody concentration and optimal EuA highly sensitive Kim-1-TRFIA was established. With this immunoassay, a good differential diagnosis can be made, and healthy people and AKI patients can be differentiated by detecting the concentration of Kim-1 in the serum. Moreover, the severity of AKI patients can be determined.

Au cluster-incorporated TiO2 nanosheets with exposed (001) facets were designed and fabricated using a facile self-assembly strategy. The glutathione-protected Au clusters act as both a co-catalyst and a photosensitizer and significantly enhance the light absorption efficiency and photocatalytic hydrogen production simultaneously.

Recent years have witnessed increasing popularity in the use of automatic written evaluation (AWE) in the writing context for its immediacy and high accessibility for EFL learners. Meanwhile, the effectiveness of the AWE tool in writing accuracy and ability is fully appreciated by the previous researchers. However, students' engagement in the revising process, key factors that mediate the uptake of feedback, and learning effect have not aroused much attention as expected. Thus, this review aimed to depict a broader picture of learners' behavioral, cognitive, and affective engagement in AWE feedback to bring a further understanding of how learners process the feedback and make the decision from a psychological perspective. Firstly, widely adopted targets in AWE research are discussed. Then, the definition of learner engagement and its constructs are presented based on existing research. After that, the link between AWE feedback and learner engagement has been taken into consideration. Finally, conclusions and suggestions are provided for insightful studies.

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Streptococcus pneumoniae is the most common pathogenic bacterium of pneumonia and can cause death. Here, we examined the impact of Baicalein on mouse mortality caused by Streptococcus pneumoniae infection. Baicalein protected mice from Streptococcus pneumoniae-induced deaths. Baicalein reduced alveolocapillary membrane permeability, lung infiltration of inflammatory cells, inflammatory cytokine production and pulmonary cell apoptosis. These evidences show that Baicalein is useful in the therapy of a severe form of pneumonia that can cause deaths.

A WO3/g-C3N4 composite photocatalyst with 2D–2D heterostructure was designed and constructed to boost the visible light performance for degradation of organic pollutants by an in situ preparation strategy. The degradation of RhB as a model reaction was used to evaluate the photocatalytic activity of the WO3/g-C3N4 photocatalyst. The optimized mass fraction of WO3 is 13% for the WO3/g-C3N4 composite photocatalyst, namely the CNW-13 sample, which can almost completely degrade the pollutant in 40 min under 70 W metal halide lamp irradiation. The different contents of WO3/g-C3N4 composite photocatalysts were investigated in detail by a series of detailed characterization measurements. Based on the trapped active species and photoelectrochemical experiments, the enhanced photocatalytic performance of WO3/g-C3N4 can be ascribed to the formation of a Z-scheme system to accelerate the separation and transfer of photo-generated charge carriers. Furthermore, the major active species, superoxide radical (˙O2−), also can be determined by active species-trapping experiments. It is expected that our current work could provide a counterpart to further develop the efficient composite photocatalysts in practical applications.

Because China is becoming an aging society, the incidence of diabetes and diabetic foot have been increasing. Diabetic foot has become one of the main health-related killers due to its high disability and mortality rates. Negative pressure wound therapy (NPWT) is one of the most effective techniques for the treatment of diabetic foot wounds and great progress, both in terms of research and its clinical application, has been made in the last 20 years of its development. However, due to the complex pathogenesis and management of diabetic foot, irregular application of NPWT often leads to complications, such as infection, bleeding and necrosis, that seriously affect its treatment outcomes. In 2020, under the leadership of Burns, Trauma and Tissue Repair Committee of the Cross-Straits Medicine Exchange Association, the writing group for ‘Consensus on the application of negative pressure wound therapy of diabetic foot wounds’ was established with the participation of scholars from the specialized areas of burns, endocrinology, vascular surgery, orthopedics and wound repair. Drawing on evidence-based practice suggested by the latest clinical research, this consensus proposes the best clinical practice guidelines for the application and prognostic evaluation of NPWT for diabetic foot. The consensus aims to support the formation of standardized treatment schemes that clinicians can refer to when treating cases of diabetic foot.

Aiming at the problems of low bandwidth utilization, severe inter-carrier interference, and the difficulty in service upgrades in the current digital radio over fibre (DRoF) system, this paper proposes a multi-carrier combination and division algorithm based on digital baseband modulation. The algorithm modulates the sub-carrier in the digital baseband domain and realizes multi-carrier combination and division in the limited frequency band. Besides, it adjusts the parameters in real time according to the bandwidth and insertion loss of each channel. In this way, the algorithm improves the frequency band utilization, optimizes the inter-carrier interference and the signal-to-noise ratio, reduces the transmission link rate. In this paper, a complete simulation system of multi-carrier combination at the transmitting end and multi-carrier division at the receiving end is built. And the three-carrier combination and division performance test are completed in the multi-service digital distributed antenna system (DDAS). Simulation and experimental results show that the algorithm greatly improves the signal transmission performance of adjacent frequency multi-channel systems, implying that the algorithm can be applied to various multi-service communication systems.

The Maiji Grottoes a famous grotto group located on the ancient “Silk Road”. It occupies a significant place in the history of grottoes and has also contributed to the communication of Buddhist art. Since the 1970s, the Chinese government and restoration professionals have made many efforts to restore the Maiji Grottoes for purposes of both scientific research and cultural protection. However, some severe diseases have repeatedly broken out in several grottoes, which require urgent treatment. In this paper, 21 grottoes and about 137.72 m2 of murals from 21 grottoes reinforced by PVAc emulsion were investigated. The results indicated the most common diseases are cracking, hollowing, discoloration, mildew, saline-alkaline and flaking. These diseases have a close relationship with the microenvironment of each grotto. Moreover, the LC analysis showed the PVAc look like remained practically the same reinforce effect, regardless of changes in time and climate. Thus, the PVAc could be used in the protection of murals for which a controlled environment should be provided to prevent these renewed diseases.

Introduction Allogeneic and xenogeneic skin are recognized as the best coverings for skin burn wounds, but currently face a supply shortage. To solve this problem, our research group developed a standardized manufactured hydrogel dressing based on a new type of highly bioactive recombinant human collagen. Study design Prospective self-controlled trial. Objective To evaluate the efficacy and safety of recombinant human collagen hydrogel in the treatment of partial burn wounds to the skin compared to those of xenogeneic skin. Methods This study included twenty-one patients admitted to Shanghai Changhai Hospital within 48 h after receiving partial-thickness skin burns. The wounds were symmetrically separated along the axis and treated with recombinant human collagen hydrogel (RHCH) or a human-CTLA4-Ig gene-transferred pig skin xenotransplant. The condition of the wound surfaces was recorded on days 0 (of enrollment), 5, 10, 15, and 20, and bacterial drug sensitivity testing, hematuria examination, and electrocardiographic tests were conducted on days 0, 10, 20, or on the day of wound healing. Results There were no statistically significant differences in wound healing time between the two groups. The median number of days to healing was 11.00 ± 0.56 for xenogeneic skin vs. 11.00 ± 1.72 for RHCH. Conclusion During the observation period, the therapeutic effect of the RHCH developed by our group on partial-thickness burn wounds was not significantly different from that of gene-transferred xenogeneic skin. Thus, our designed RHCH shows potential for clinical use to treat burn wounds on the skin.

Droplet digital PCR (ddPCR) is a single-molecule amplification technology with broad applications in precision medicine and clinical diagnosis. Dual-fluorescence and four-cluster ddPCR (two/four-ddPCR) assay is an effective way to quantify copy numbers. Currently, two/four-ddPCR data are usually classified with manual thresholds. For clinical applications, automatic and accurate methods are required to avoid subjectivity in diagnosis. Although there are some automatic classification algorithms, their accuracy and robustness still need to be improved to meet the needs of clinical diagnosis. Therefore, a new method is in high demand to automatically classify two/four-ddPCR data in an accurate and robust way. Here, a novel density-watershed algorithm (DWA) method was developed for the accurate, automatic and unsupervised classification of two/four-ddPCR data. First, data gridding was applied to a scatter plot of the fluorescence signal intensity to calculate data densities. Based on the data densities, the watershed algorithm was used to divide the gridded scatter plot into isolated regions automatically. Next, an optimal cluster pattern was determined based on these isolated regions, and excess regions were merged. Finally, the two/four-ddPCR data were classified based on the merged regions, and DNA template copy numbers were calculated accordingly. Using the DWA method for the quantification of both wild types and mutants of epidermal growth factor receptor (EGFR) L858R and T790M, the classification results were highly consistent with expectations, and significantly better than commonly-used automatic algorithms for now. The computed template copy numbers scaled proportionally to the relative concentration of input templates (r2 > 0.998) in four orders of magnitude with a good reproducibility, and achieved a limit of detection over 40 times lower than the commonly-used automatic algorithms. Furthermore, the DWA method was validated on 254 clinical DNA samples derived from frozen tissues, formalin-fixed paraffin-embedded tissues and peripheral blood. In most cases, the DWA method derived accurate and valid classification results. This highly effective DWA method may be widely used for automatically classifying two/four-ddPCR data, and it will greatly promote the application of ddPCR in clinical diagnosis.

Highly-sensitive and contamination-free droplet digital PCR (ddPCR) is an enabling technology and widely needed for accurate quantification of nucleic acid in clinical applications. In this paper, a novel droplet reader was developed by combining a "quasi" confocal laser-induced fluorescence (LIF) cytometry with a delicate microfluidic chip design. The droplets with a size of 90 μm was illuminated at an out-of-focus position by two aligned laser beams to generate maximum fluorescent signal. Additionally, the lateral offset position of the microfluidic chip should be precisely tuned so that the bandwidth of the FAM and VIC channels were configured at the matching sizes. Then, PMT gain voltages and pneumatic pressures were optimized for better droplet detection efficiencies. An aerosol adsorption experiment was performed to demonstrate that there was no aerosol contamination, and detected copy numbers of both mutants and wild types scaled linearly with the expected input copy numbers (r2>0.998) with a LoB of 0.0 copies and LoD of 3.0 copies. The results demonstrated that this droplet reader with the delicate chip is a convenient, highly-sensitive and contamination-free to detect fluorescence signals inside droplets after ddPCR, which is highly promising for broad applications of ddPCR in clinical diagnosis.

Anti-phospholipase A2 receptor antibody (PLA2R-Ab) is useful for affirming the diagnosis of idiopathic membranous nephropathy (IMN). Time-resolved fluoroimmunoassay (TRFIA) is highly sensitive and quantitative for measuring serum PLA2R-Ab immunoglobulin (IgG). We measured PLA2R-Ab levels with TRFIA in sera from 172 patients with IMN (n = 69), secondary MN (n = 9), and those with other glomerulonephritis (n = 94) at the time of renal biopsy compared to healthy controls (n = 286). Serum anti-PLA2R-IgG levels in healthy volunteers ranged from 0.09–0.91 mg/L. We set the cutoff value of the anti-PLA2R-IgG titer at 0.91 mg/L, with a sensitivity of 84.06% for diagnosing IMN. Increasing the cut-off value to 2.025 mg/L altered the sensitivity for diagnosing IMN to 71.01%, but with 100% specificity. IMN patients had significantly higher serum anti-PLA2R-IgG levels compared to those with secondary MN. PLA2R-Ab titers negatively correlated with estimated glomerular filtration rate (eGFR). Patinets with high titers had significantly lower serum albumin and eGFR, higher proteinuria and serum creatinine levels, accompanied by a lower complete remission rate. High titers of PLA2R-Ab were associated with poor prognosis of patients with IMN. TRFIA-based quantification of anti-PLA2R-IgG can be a reliable approach for the diagnosis and prognostication of patients with IMN.

This study aimed to evaluate the potency of optical coherence tomography (OCT) to detect early occlusal caries compared with clinical visual examination.Approximately 97 sites of occlusal fissures on 77 extracted accessional human teeth were scored by three examiners using conventional visual examination and OCT. Results of histological examination on these sites obtained by polarimicroscope served as a gold standard to analyze the sensitivity (SE), specificity (SP), positive predictive value (PPV), and negative predictive value (NPV). Results of the area under receiver operating characteristic (ROC) curve (AUC) by visual examination and OCT were also analyzed. The Spearman's rank correlation coefficient with histology and the inter-examiner reliability were compared.For sites of enamel demineralization limited to the outer 1/2 of the enamel layer, the detection rate of OCT (14/25) was obviously higher than that of the clinical and visual examination (3/25). SE, SP, PPV and NPV of OCT during diagnosis of the early occlusal caries (0.83, 0.64, 0.87 and 0.57) were higher than that of the visual examination (0.79, 0.60, 0.85 and 0.50). AUC (95%CI) of OCT and the visual examination were 0.737 (0.569-0.822) and 0.696 (0.614-0.859), respectively. No statistically significant difference was observed between the results. Results of OCT correlated well with histology (r=0.559, P0.05). The inter-examiner reliability of OCT was medium.OCT can accurately detect early occlusal lesions atraumatically with high sensitivity and effectiveness. OCT exhibits the potential of auxiliary clinical diagnosis enhancing detection rate and finally implementing early diagnosis and early intervention of early occlusal lesions in clinical practice.目的 比较光学相干断层成像技术（OCT）与临床探视诊对人牙窝沟早期釉质龋的检出效能。 方法 获取77颗人离体恒磨牙面的97个可疑早期龋位点OCT二维图像，由3位临床医师双盲法分别通过OCT图像和探视诊方法对这些位点进行评分，以偏光显微镜获取的组织学图像为金标准，评估OCT、临床探视诊检出早期窝沟龋的敏感度（SE）、特异度（SP）、阳性预测值（PPV）、阴性预测值（NPV）及其与组织学评分结果的相关性；采用Kappa检验分析检测者间评分结果的一致性，采用非参数法Z检验比较受试者工作特征（ROC）曲线下面积（AUC）。 结果 对于脱矿局限于釉质表层外1/2的窝沟早期龋，OCT检出率（14/25）明显优于探视诊（3/25）。OCT检出窝沟早期釉质龋的SE、SP、PPV、NPV（0.83、0.64、0.87、0.57）均高于探视诊（0.79、0.60、0.85、0.50）。OCT与探视诊检测窝沟早期龋的AUC（95% CI）分别为0.737（0.569~0.822）、0.696（0.614~0.859），二者间差异无统计学意义。OCT评分与组织学评分呈正相关（r=0.559，P0.05），检测者间检测结果的一致性为中等。 结论 OCT能够敏感、无创、有效地检出早期窝沟龋，具有辅助临床探视诊检出早期窝沟龋的应用潜能。.

The Shihu gold deposit, situated in the Taihang Mesozoic orogen of the North China Craton (NCC), is hosted by ductile-brittle faults within Archean metamorphic core complex. The deposit is characterized by gold-bearing quartz-polymetallic sulfides veins. The Mapeng granitoids stock and intermediate-basic dikes intruded the metamorphic basement rocks, and are spatially related to gold mineralization. Detailed laser ablation inductively coupled plasma mass spectrometry (LA ICP-MS) U-Pb zircon ages of the granitic rocks, dykes and mineralized quartz veins in the studied area reveal its magmatic and mineralized history. The mineralized quartz veins contain inherited zircons with ages of about 2.55 Ga and 1.84 Ga, probably coming from the basement. These two Precambrian events are coeval with those in other parts of the NCC. The Mapeng granitoid stock, the largest intrusion in the area, was emplaced at ca. 130 Ma, and is coeval with magmatic zircon populations from diorites and quartz diorite pophyrites in the same region. The ca. 130 Ma magmatism and gold mineralization were most likely related to an underplating event that took place in the Taihang orogen at Late Mesozoic. The timing of gold mineralization with respect to felsic magmatism in the area is similar to those observed in other major gold-producing provinces in the NCC. This episode is simultaneous with those in the eastern margin of NCC, indicative of a widespread late Yanshanian metallogenic event that was a response to the Early Cretaceous lithosphere in the eastern NCC, in which the mesothermal gold deposits were formed from similar tectono-magmatic environments.

Clear water scour experiments with a wide range of water discharge were conducted on uniform and non-uniform beds. The fractional transportability in non-uniform runs is compared with that of the same fraction in uniform runs. It is found that in non-uniform runs, the fractional transportability of gravel is greatly promoted compared with that in uniform runs by the same proportion, while the transportability of sand fraction is obviously inhibited. Furthermore, although the transport rate of sand is undoubtedly much greater than that of gravel under the same flow strength in uniform runs, the transport rates of sand fraction and gravel fraction are found to be nearly the same in non-uniform runs.

With the rapid growth in consumer electronics, people expect thin, smart and powerful devices, e.g. Google Glass and other wearable devices. However, as portable electronic products become smaller, energy consumption becomes an issue that limits the development of portable systems due to battery lifetime. In general, simply reducing device size cannot fully address the energy issue. To tackle this problem, we propose an on-chip interconnect infrastructure and pro- gram storage structure for a coarse-grained reconfigurable architecture (CGRA) with emerging non-volatile embedded memory (MRAM). The interconnect is composed of a matrix of time-multiplexed switchboxes which can be dynamically reconfigured with the goal of energy reduction. The number of processors performing computation can also be adapted. The use of MRAM provides access to high-density storage and lower memory energy consumption versus more standard SRAM technologies. The combination of CGRA, MRAM, and flexible on-chip interconnection is considered for signal processing. This application domain is of interest based on its time-varying computing demands. To evaluate CGRA architectural features, prototype architectures have been pro- totyped in a field-programmable gate array (FPGA). Measurements of energy, power, instruction count, and execution time performance are considered for a scalable num- ber of processors. Applications such as adaptive Viterbi decoding and Reed Solomon coding are used for evaluation. To complete this thesis, a time-scheduled switchbox was integrated into our CGRA model. This model was prototyped on an FPGA. It is shown that energy consumption can be reduced by about 30% if dynamic design reconfiguration is performed.

Pneumatic conveying of granular material through the upward inclined pipe was studied by using the numerical simulation based on ANSYS platform. Euler- Lagrange two-phase method and discrete phase model were adopted to simulate the pneumatic conveying process. Three kind of inclined pipes with different angles were studied. The results showed the flow pattern, motion trajectory and pressure distribution in the pipes of particle. Through the simulation results, it was found that the particles flowing in the pipe was mainly influenced by gravity and inertia force, in addition to collision between particles or particle and pipe wall.

Webkit, as an open-source browser engineer, has higher speed, less memory and other notable features. In the paper, introduced the framework of Webkit and the Linux browser-related techniques, studied the core models and improved the function of Webkit by object WebKitWebView and locale setting, made it support Multi-window display and Chinese pages, realized the basic uses of browser. When it runs, it costs less resource, having the higher speed of image rendering. This Linux browser will have a good application prospects.

Multicast technology introduces a number of new applications; meanwhile, it reduces the congestion of the network and releases the burden of the server. Those characteristics, such as reducing the occupied bandwidth, reducing server load, improving the quality of data transmission, are especially applicable to the needs of large bandwidth multimedia applications such as audio, Video. This new technology has become a hot topic in Internet circles, and to fundamentally change the network architecture. Although multicast technology has also brought some problems, such as routing instability, the network load imbalance, QoS fluctuations, but its application is still very wide.

The effects of in vivo local expression of recombined human tissue-type plasminogen activator (t-PA) gene on the thrombosis and neointima formation of vein grafts were explored. Jugular vein-to-artery bypass grafting was performed on 72 New Zealand white rabbits. The rabbits were divided into 3 groups according to the different processing methods: transfected t-PA gene group (n = 24), vector group (n = 24) and blank control group (n = 24). Samples of vein grafts were harvested at different time points after surgery. The expression of t-PA gene in vein graft was detected by RT-PCR and the synthesis of t-PA protein by Western-Blot assay. The t-PA activity was measured by chromogenic substrate assay. The Cr51 labeled platelets accumulation in vein grafts was counted. The histopathological changes were compared in intima hyperplasia index among the three groups after operation. The results showed that at the 2nd, 5th, 14th and 28th day after operation, RT-PCR and Western-blot confirmed the expression of t-PA mRNA and protein at the site of gene transfer. The t-PA activity detected on the 2nd, 5th, 14th and 28th day in experimental group was 370.63 +/- 59.44, 344.13 +/- 48.47, 252.87 +/- 51.80 and 161.75 +/- 68.94 U/g respectively, and disappeared on the 60th day and undetected in the control groups. The number of platelets accumulated in the vein grafts in gene group, vector group and blank control group was (85.04 +/- 21.58) 10(6), (225.87 +/- 85.13) 10(6) and (211.7 +/- 78.02) 10(6) respectively. The number of platelets accumulated in gene group was significantly fewer than that in the control groups. Morphometric analysis revealed that intimal hyperplasia was markedly reduced in the t-PA gene group as compared with that in the control groups. It was suggested that the local expression of t-PA gene in vein graft significantly inhibited the accumulation of platelets, thrombosis and concomitant intimal hyperplasia, by which stenosis of bypass graft could be prevented effectively.

Based on Lyapunov's theory of stability, a equation of sufficient condition for multivariable linear delayed systems with delayed independent stabilization is derived and another forms are also given. Based on this, several simple criterions for judging independent stabilization from linear delayed system are presented. We also discuss the exponential stability for delayed system and also provide the sufficient condition of exponential stability with any appointed convergent rate and its corresponding deductions. Using these conditions, we can choose a set of suitable parameters to reduce the conservation. By calculating and being compared with methods of the literature, the results show that our methods have less conservation.

In this paper, a new design concept of an isolated cradle trusslike structure to support vibrating machinery is proposed. The acoustic and vibratory energy transmission in this isolation system is investigated to improve the vibration isolation performance of conventional floating raft system. The finite element method and experimental measurements are used to understand the dynamic behavior of this cradle truss. In conjunction with experiments, a vectorial four pole parameter numerical model is used to identify power flow of the floating raft isolation system. The proposed floating raft design achieved a vibration reduction of 30–40dB in the frequency range of 20–600Hz. It is also shown that the loss factors of the cradle truss configured floating raft are up to 4dB than conventional floating flat raft.

Double plate is widely used to isolate the vibration and noise in the air,it needs more research on the underwater application.The vibration model of double plate with periodic connectors was built up.The transmission path of power was analyzed carefully and this analysis revealed the specific frequency and wavenumber selective characteristics of double plate in comparison with the single plate.The incident sound wave and the turbulence have very different frequency and wavenumber's spectrum,this may introduce very interesting usage in the sonar dome which needs consideration of both sound wave and turbulence.

Cavity noise in the cube with multiple layer composite plate as the back panel was predicted and analyzed in this paper. The mode solution was used to solve this acoustical problem,the mode strain and stress transmission matrix in the composite plate was built up,this paper chose the Corcos model as the turbulent boundary layer pressures's wavenumber-frequency spectrum.The cavity noise was calculated,the sound pressure level's difference between the theory and experiment was less than 3dB,the method in this paper can be used to predict the cavity noise underwater.