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Accurate and reliable detection of exosomal miRNA can serve as a promising method for early diagnosis of disease and evaluation of therapeutic effects. However, current exosomal miRNA detection methods commonly involve exosome enrichment, containing RNA extraction, and qRT-PCR based quantification, which are expensive and time-consuming. Herein, we develop a DNA zipper-mediated membrane fusion approach for rapid exosomal miRNA detection and cancer diagnosis. First, a lipid vesicle probe containing miR21-targeting molecular beacons (MBs) is constructed and further loaded with zipper DNA constructs (ZDCs) on its surface. Meanwhile, complementary zipper DNA constructs (cZDCs) are introduced on the exosome of interest. Upon mixing them together, zipping between ZDC and cZDC induces the membrane fusion of exosomes and vesicle probes, triggering the recognition of exosomal miR21 by contained MBs and fluorescence emission that can be conveniently detected within 30 min. Importantly, with the assistance of flow cytometry, miR21-overexpressed tumor exosomes derived from either cell culture medium or clinical patient serums can be distinguished from exosomes secreted from normal cells. This approach provides a convenient way to accurately detect the exosomal miRNA, which may hold great potential in liquid biopsy for early cancer diagnosis and monitoring the therapeutic effects during the treatments.

Aiming at the problems of low reconstruction rate and poor reconstruction precision when reconstructing sparse signals in wireless sensor networks, a sparse signal reconstruction algorithm based on the Limit-Broyden-Fletcher-Goldfarb-Shanno (L-BFGS) quasi-Newton method is proposed. The L-BFGS quasi-Newton method uses a two-loop recursion algorithm to find the descent direction dk directly by calculating the step difference between m adjacent iteration points, and a matrix Hk approximating the inverse of the Hessian matrix is constructed. It solves the disadvantages of BFGS requiring the calculation and storage of Hk, reduces the algorithm complexity, and improves the reconstruction rate. Finally, the experimental results show that the L-BFGS quasi-Newton method has good experimental results for solving the problem of sparse signal reconstruction in wireless sensor networks.

The traditional fixing method for coverage gap in wireless sensor network (WSN) mainly targets the homogenous networks, in which all nodes have the same detection radius. By this method, the gaps in the network are covered randomly by mobile nodes, leading to low coverage and resource waste. Considering the different detection radii of actual WSN nodes, this paper explores the gap fixing in heterogenous WSNs, and proposes an improved gap fixing method based on fixing priority. Specifically, the gap fixing points were determined and prioritized with the aid of Voronoi polygons, and then fixed by mobile nodes. After that, the nodes with overlapping sensing ranges were removed to reduce the redundancy. Simulation results show that the improved method can effectively enhance the coverage of the entire network.

It is difficult for traditional circuit-fault feature-extraction methods to accurately distinguish between nonlinear analog-circuit faults and analog-circuit faults with high fault rates and high diagnostic costs. To solve this problem, this paper proposes a method of mathematical morphology fractal dimension (VMD-MMFD) based on variational mode decomposition for soft-fault feature extraction in analog circuits. First, the signal is decomposed into variational modes to suppress the influence of environmental noise, and multiple high-dimensional eigenmode functions with different center frequencies are obtained. The fractal dimension of the signal feature information component IMF is calculated, and then, KPCA (Kernel Principal Component Analysis) is used to remove the overlapping and redundant parts of the data. The fault set obtained is used as the basis for judging the working state and the fault type of the circuit. The experimental results of the simulation circuits show that this method can be effectively used for circuit-fault diagnosis.

Aiming at the problems of nonlinearity and serious confusion of fault characteristics in analog circuits, this paper proposed a fault diagnosis method for an analog circuit based on ensemble empirical pattern decomposition (EEMD) and improved multifractal detrended fluctuations analysis (MF-DFA). This method consists of three steps: preprocessing, feature extraction, and fault classification identification. First, the EEMD decomposition preprocesses (denoises) the original signal; then, the appropriate IMF components are selected by correlation analysis; then, the IMF components are processed by the improved MF-DFA, and the fault feature values are extracted by calculating the multifractal spectrum parameters, and then the feature values are input to a support vector machine (SVM) for classification, which enables the diagnosis of soft faults in analog circuits. The experimental results show that the proposed EEMD-improved MF-DFA method effectively extracts the features of soft faults in nonlinear analog circuits and obtains a high diagnosis rate.

Because of their excellent optical and electrical properties, doped carbon quantum dots (CQDs) are expected to be used in novel film optoelectronic devices such as light-emitting diodes and solar cells. However, these device advancements are currently hindered by the elusive photophysical process of doped CQDs in solid-state films. Here, the optical properties of nitrogen-doped CQD (N-CQD) films are studied using spectro-electrochemical (SEC) methods. A distinctive photoluminescence (PL) enhancement phenomenon is observed, in which the PL intensity of the N-CQD film can be increased in both positive and negative electrochemical potential sweeps. The effect of positive potential on PL enhancement is greater (∼340% at +1.4 V), while that of negative potential is slightly weaker (∼10% at -1.4 V). To the best of our knowledge, no similar brightening process has been reported in all previous SEC studies on a variety of QDs, wherein the emission intensity can only exhibit enhancement under positive or negative potential at most. We propose that the above PL brightening is related to the weakened π-π stacking effect after electrochemical charge injection and nitrogen doping plays a crucial role in it. Finally, a low hysteresis reversible electrochemistry regulation of the PL spectrum can be achieved by increasing electrolyte fluidity with argon gas bubbling to reduce local charge aggregation.

Full well capacity (FWC) modeling has been widely used to clarify the imaging characteristics of the pinned photodiode (PPD) in complementary metal-oxide-semiconductor (CMOS) image sensors. Until now, FWC modeling has considered only the effects of temperature, doping, and photon dependence on the FWC. However, the influence of the distribution of interface trap-state energy levels on the FWC is ignored. Therefore, this article proposes a dynamic FWC model that depends on the energy-level distribution of interface trap states in a PPD for the first time. By establishing a 2-D function for the reverse saturation current related to the trap-state density and trap energy level, an explicit 2-D expression is derived for the full well potential associated with trap-state density and trap energy level. According to the relationship between the full well potential and FWC, as well as the relationships among the trap-state density, trap energy level, and trap energy-level distribution, a dynamic model of the FWC is deduced that depends on the trap energy-level distribution. The consistency between results of TCAD simulations and our theoretical model shows that the FWC is not a single fixed value but a set of dynamic values that change with the distribution of trap energy levels.

Aiming at the problems of data loss and uneven energy consumption in wireless sensor networks during data transmission, this paper proposes a ReInForM transmission fault-tolerant routing algorithm based on energy selection and erasure code fault-tolerant machines (E-ReInForMIF). The E-ReInForMIF algorithm improves the multi-path routing algorithm by combining an erasure coding fault-tolerant machine and node residual energy sorting selection. First, the erasure coding fault-tolerant machine is used to encode the signal, determine the number of transmission paths through multi-path routing, and then select the specific node of the next hop by sorting the residual energy of the node. The E-ReInForMIF routing algorithm effectively solves the problems of uneven energy consumption and data loss in data transmission, improving network lifespan and transmission reliability. Finally, the signal is decoded. The simulation results show that the E-ReInForMIF routing algorithm is superior to the ReInForM routing algorithm in improving the reliability of data transmission.

William Shakespeare is one of the most famous dramatists in England history. His works are popular from the Renaissance in Europe to now. The Merchant of Venice, which is called one of the four great comedies, is presented to people again in the form of films several centuries later. This paper tries to analyze it from the perspective of Cooperative Principle, which is one of the most important theories in linguistics. Through analysis, it is found that the violation of Cooperative Principle in the movie leads to the production of the conversational meaning, which can better shape the character of the figures; intensify the conflict between characters; facilitate the development of the plot, and attract people’s eyes. This paper is a meaningful attempt to analyze the movie in terms of linguistic theory and provide some inspiration for the study of other literary works.

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The improvement of coverage is a critical issue in the coverage hole patching of sensors. Traditionally, VOPR and VORCP algorithms improve the coverage of the detection area by improving the original VOR algorithm, but coverage hole patching algorithms only target homogeneous networks. In the real world, however, the nodes in the wireless sensor network (WSN) are often heterogeneous, i.e., the sensors have different sensing radii. The VORPH algorithm uses the VOR in a hybrid heterogeneous network and improves the original algorithm. The patched nodes are better utilized, and the detection range is enlarged. However, the utilization rate of the patched nodes is not optimized, making it impossible to patch the coverage holes to the maximum degree. In the environment of hybrid heterogeneous WSN, we propose a coverage hole patching algorithm with a priority mechanism. The algorithm determines the patching priority based on the size of the coverage holes, thereby improving network coverage, reducing node redundancy, and balancing resource allocation. The proposed algorithm was compared under the same environment by simulation and analysis. The results show that our algorithm is superior to the traditional coverage hole patching algorithms in coverage rate, and can reduce node redundancy.

Narrow-band perovskite photodetectors based on the charge collection narrowing (CCN) mechanism have developed rapidly owing to their narrow-band spectral response in the visible and near-infrared range. However, they face problems such as low external quantum efficiency (EQE) and an insufficiently narrow bandwidth. To solve these problems, a new method that uses the barrier effect between the electron blocking/hole transport layer and the perovskite absorption layer is proposed to realize the CCN mechanism. Based on this new method, a new narrow-band perovskite photodetector is designed. In the device, the electron blocking/hole transport layer plays the dual role of blocking the transport of photogenerated electrons in perovskite absorber layer-1 to the cathode and promoting the transport of photogenerated holes in perovskite absorber layer-2 to the anode. By changing the thickness of the perovskite absorber layer, an ultra-narrow-band perovskite photodetector with a full width at half maximum of 9 nm was finally realized. The simulation results showed that the peak EQE of the device with the optimal performance under zero bias was as high as 59.13%, and the spectral responsivity reached as high as 0.376 A W−1. Both of these metrics were higher than those of other existing narrow-band perovskite photodetectors based on the CCN mechanism.

To obtain feature information of soft faults in non-linear analog circuits in a more effective way, this paper proposed a novel feature extraction method for soft faults in non-linear analog circuits based on Local Mean Decomposition-Generalized Fractal Dimension (LMD-GFD) and Kernel Principal Component Analysis (KPCA). First, the fault signals were subject to LMD, the features of each component signal were extracted by GFD for the first time, and a high-dimensional feature space was formed. Then, KPCA was employed to reduce the dimensionality of the high-dimensional feature space, and feature extraction was performed again; at last, KPCA and Support Vector Machine (SVM) were adopted to diagnose the faults. The experimental results showed that the proposed LMD-GFD-KPCA method had effectively extracted the features of the soft faults in the non-linear analog circuits, and it achieved a high diagnosis rate.

The application of intensity-based H2O2-responsive fluorescence nanoprobe for circulating tumor cell detection was limited by the complex background and the nanoprobe uptake in each CTC. In this context, we developed a ratiometric fluorescence nanoprobe, on which a H2O2-responsive subunit and a stable subunit grafted working as a H2O2 detector and a reference, respectively. When responding to intracellular H2O2, the reference fluorescence (580 nm) maintained as a correction background while the detector fluorescence (450 nm) was turned on to conduct CTC enumeration and intracellular H2O2 evaluation. Two normal cells and three colon cancer cells were examined to evaluate their endogenous H2O2 with the ratiometric nanoprobe by flow cytometry and confocal laser scanning microscopy. CTC sample from colorectal cancer patients was used to validate the performance of the nanoprobe for CTC enumeration and H2O2 evaluation. The results indicated that not only CTC could be effectively identified based on the “turn on” fluorescence, but also the viability of the identified CTCs could be assessed with the intensity of the reference fluorescence to avoid the false-positive number. Moreover, the clinical results demonstrated that the viability CTC count combined with intracellular H2O2 content (described as I450/580)were related to the tumor TNM stage, which might provide significant guidance for clinical treatments.

A novel form of magnetic bead, namely antibody-coated magnetic lipid nano-vehicle (AMLV), was synthesized by embedding Fe3O4 nanoparticles into an amphiphilic antibody-modified liposome as a high-performance circulating tumor cell (CTC) hunter. The CTC capture performance of AMLV was validated based on an enlarged patient sample (including 318 colorectal, 78 breast, 77 lung and 55 liver cancer patients) with high detection rate. The preliminary comparison with Cellsearch was also conducted, indicating that the cell membrane-semblance AMLVEpCAM showed higher capture performance for different kinds of EpCAM-expressed circulating tumor cells in the peripheral blood (4.4 ± 1.2-fold for AMLVEpCAM vs CellsearchTM, n=5, P

Purpose Castration resistance prostate cancer patients showing resistance to the androgen deprivation therapy always have low five-year survival rate and worse prognosis. A responsive NIR fluorescent probe was designed to report the androgen dependence and monitor the development of castration resistance for prostate cancer. Methods Intratumoral H2S in prostate cancer was closely related to castration resistance. A H2S-responsive NIR probe (HM) was developed as a dependent indicator to report the androgen dependence of prostate cancer. The specificity of HM to H2S and the influence of normal intracellular substrates to the response between H2S and HM were determined. Cell/in vivo animal imaging were performed on PC-3 and LnCAP cell/tumor bearing mice, which presented with androgen independence and androgen dependence, respectively. Results When HM responded to H2S, strong fluorescence at 770 nm could be rapidly turned on in 5 min with the stokes shift as large as 200 nm. The recognition between HM and H2S showed high specificity. Neither other common substrates showed capacity to turn on HM's fluorescence, nor their existence demonstrated competition. The fluorescence intensity was linearly dependent to the H2S concentration and the limited of detection was 0.15 μM. When HM was applied to PC-3/LNCaP prostate cancer cell and tumor, the intracellular and intratumoral H2S could be clearly imaged and monitored. Conclusion HM showing obvious fluorescent behaviors in androgen dependence and independence prostate tumor, which could work as an indicator to reported the androgen dependence of prostate cancer and monitor the development of castration resistance.

In order to expand the color gamut of liquid crystal displays, colloidal semiconductor nanocrystals (NCs) with narrow emission peaks were introduced as down-converters for the backlight, in which the green-emitting NC is the critical and challenging part. Herein green-emitting CdZnSe ternary NCs, with narrow emission line width of ∼18 nm, were synthesized. By combining these green-emitting NCs with blue light-emitting diode and red-emitting CdSe-based NCs a wider color gamut of ∼136% can be reached, relative to the National Television Standard Committee (NTSC) in the 1931 CIE color coordinates space. The influence factors on narrow line width, such as size/morphology distribution and surface state, were investigated by transmission electron microscope (TEM) images and time resolved spectrometry. The synthetic conditions of these NCs were discussed also.

Intracellular cysteine and glutathione was deemed as the most important reductants in the cell and played significant roles in the cellular homeostasis and redox adjustment. Here we developed a NIR fluorescent probe (HI) to detect and report the intracellular cysteine and glutathione, and monitor the development of the drug resistance of tumor. HI with both excited wavelength and emitting wavelength located within near infrared area showed no fluorescence in the normal physiological environment. However, when HI responded to cysteine and glutathione, strong NIR fluorescence could be turned on, which was linear dependent to the cysteine concentrations and the limited of detection was 0.18 μM. The response between HI and cysteine/glutathione demonstrated high specificity and no other amino acids showed influence or competition. The HPLC identification of the recognition results confirmed the response of acryloyloxy on the HI and active sulfhydryl on the cysteine/glutathione. DFT calculation of the HOMO and LUMO energy before and after response revealed the intramolecular charge transfer mechanism that induced the generation of the fluorescence. When HI was incubated with PATU-8988 and PATU-8988/Fu cell, the intracellular cysteine and glutathione could be clearly imaged and monitored by the enhanced fluorescence. Meanwhile, when HI was applied to the tumor-bearing mice, the drug resistance of tumor could be monitored and reported.

Plasmonic color filters based on nanostructure have the advantages of stable color, small size and good color reproduction, which exhibit promises as an alternative for existing colorant-based filters. However, the color gamut produced by the existing filters is relatively narrow and cannot exceed the sRGB color space so that the limited color gamut limits the further application of the plasmonic color filters. In order to overcome this drawback, we propose a color filter scheme based on surface plasmon resonance (SPR), which can obtain a color range that exceeds the sRGB color space. A special nano pattern structure was etched on the surface of silver film. Under natural light incidence, the nanohole acts as a grating coupler to match the momentum between the photon and the plasma. The surface plasmon resonance occurs on the surface of the metal/medium. In this case, the plasma passes through the aperture and decays into radiant photons after passing through the metal film. By changing the structural parameters of the nano pattern, the plasmon resonance wavelength can be adjusted to obtain different transmission spectra. Converting the transmission spectrum into color coordinates and drawing on the CIE1931 chromaticity diagram can obtain a wide range of colors, and the color range and saturation can exceed the effects that other existing color filters can achieve. Because of the symmetry of the designed nanostructure, the plasmonic color filter is not sensitive to polarized light.

Radially polarized Lorentz-Gauss vortex beam with sine-azimuthal variation wavefront was proposed and its focusing properties were investigated by vector diffraction theory. The effect of phase parameter on focal pattern is very considerable, and some novel intensity pattern comes into being under certain focusing condition, including multiple-peaks, crescent shape, multiple intensity lines, intensity cross. Especially, the symmetry characteristics are systematical on increasing phase parameter. For case of even number of phase parameter, there are two symmetric axes for whole focal pattern, while there is only one symmetric axis for odd number of phase parameter. When topological charge is small, the intensity maximum shifts within small distance range, while intensity maximum may switch for higher topological charge in focal pattern evolution process.

Focusing properties of linearly polarized Lorentz-Gaussian vortex beams was investigated by vector diffraction theory, from which topological charge determination method is proposed. Results show that the focal pattern can be altered considerably by topological charge, and for certain condition, the number of dark spots along one coordinate direction equals to topological charge, and the number of intensity lines crossing focal pattern along the other coordinate direction minus topological charge is one. The intensity lines across focal pattern get weaker for higher topological charge, which leads to the boundaries among dark spots become blurring. Focal shift value of the most out dark peak increases on increasing topological charge, and the dependence curve is monotonous. Topological charge can be obtained according to dependence curve even for fractional topological charge.

Circulating tumor cells (CTCs) represent the most common way of tumor metastasis and has been considered as a significant index for tumor diagnosis, staging and prognosis. However, CTC detection and analysis are always limited by the scarcity of CTC in the peripheral blood and the interference of blood cells. Therefore, here we presented with a hydrogen peroxide (H

A detailed study of high-efficiency polymer solar cells (PSCs) based on a low bandgap polymer PBDTT-F-TT and PC 71 BM as the bulk heterojunction (BHJ) layer is carried out. By using 1,8-diiodooctane (DIO) as solvent additive to control the morphology of active layer and comparing different device architecture to optimize the optical field distribution, the power conversion efficiency (PCE) of the resulted devices can be reached as high as 9.34%. Comprehensive characterization and optical modeling of the resulting devices is performed to understand the effect of DIO and device geometry on photovoltaic performance. It was found that the addition of DIO can significantly improve the nanoscale morphology and increased electron mobility in the BHJ layer. The inverted device architecture was chosen because the results from optical modeling shows that it offers better optical field distribution and exciton generation profile. Based on these results, a low-temperature processed ZnO was finally introduced as an electron transport layer to facility the fabrication on flexible substrates and showed comparable performance with the device based on conventional ZnO interlayer prepared by sol-gel process.

Based on the diffractive vector theory, the focusing properties of annular cylindrical vector beams generated by the novel polarized convertor are investigated. By the combination of the vortex phase plate eimφ and the phase variety parameter cosφ + ihsinφ which exists naturally in the CV beams, the intensity pattern at the focus can be tailored. Flattop spot and light intensity with pure transverse and longitudinal component are formed in the focal region. More interestingly, tunable dark focal spot is also achieved. By changing h, the light intensity in the center of spot can be changed at will while the outer ring of spot remains the same. This works are important for microscope imaging and optical lithography, particle manipulation, electric acceleration etc.

Circulating tumor cells (CTCs) represent the most common way of tumor metastasis and has been considered as a significant index for tumor diagnosis, staging and prognosis. However, CTC detection and analysis are always limited by the scarcity of CTC in the peripheral blood and the interference of blood cells. Therefore, here we presented with a hydrogen peroxide (H2O2)-response nanoprobes with CD44-targeted ability to reduce the interference of blood cells and improve the detection efficiency and accuracy and the pancreatic cancer cell was used to evaluate the feasibility of our probe. Shortly, hydrophobic H2O2-response naphthalimide-borate fluorophore was introduced onto the hydrophilic hyaluronic acid to form an amphiphilic complex, which could self-assemble into fluorescent nanoprobes in water. Our studies demonstrated that the nanoprobes were not only able to specifically recognize the pancreatic cancer cells with overexpressed CD44 proteins and reduce the influence of white blood cells in the peripheral blood, but also capable of semi-quantifying H2O2 content in CTCs, Which could be further used as a significant index for tumor clinical evaluation and therapy.

In situ detection of certain specific enzyme activities in cells is deeply attached to tumor diagnosis. Conventional enzyme-responsive fluorescent probes have difficulty detecting targeted enzymes in situ in cells due to the low detection accuracy caused by the spread of fluorescence probes. In order to solve this problem, we have designed and synthesized an enzyme-responsive, water-soluble fluorescent probe with AIE characteristics, which could aggregate and precipitate to produce in situ fluorescence when reacting with the targeted enzyme in cells. The AIE fluorophore (TPEQH) was utilized to design the enzyme-responsive, fluorescent probe (TPEQHA) by introducing a phosphate group on to it, which could be specifically decomposed by the targeted enzyme, namely alkaline phosphatase (ALP). In tumor cells, TPEQH was highly produced due to the interaction of phosphate on the TPEQHA and the overexpressed ALP. Water-insoluble TPEQH then precipitated and release fluorescence in situ, thereby successfully detecting the ALP. Furthermore, the expression level of ALP could be determined by the fluorescence intensity of TPEQH with higher accuracy due to the inhibition of TPEQH leak, which demonstrated a potential application of in suit ALP detection in both clinical diagnosis and scientific research of tumor.

Epidermal growth factor receptor (EGFR) has emerged as an attracting target in the field of imaging and treatment for non-small cell lung cancer (NSCLC). Radiolabeled EGFR-tyrosine kinase inhibitors (EGFR-TKIs) specifically targeting EGFR are deemed as promising probes for the imaging of NSCLC. This study aimed to label icotinib (one kind of EGFR-TKI) with

Lu, X.-M. and Wu, Q., 2019. Coverage hole patching of hybrid wireless sensor network in marine environment. In: Gong, D.; Zhu, H., and Liu, R. (eds.), Selected Topics in Coastal Research: ...

The random telegraph signal noise in the pixel source follower MOSFET is the principle component of the noise in the CMOS image sensor under low light. In this paper, the physical and statistical model of the random telegraph signal noise in the pixel source follower based on the binomial distribution is set up. The number of electrons captured or released by the oxide traps in the unit time is described as the random variables which obey the binomial distribution. As a result, the output states and the corresponding probabilities of the first and the second samples of the correlated double sampling circuit are acquired. The standard deviation of the output states after the correlated double sampling circuit can be obtained accordingly. In the simulation section, one hundred thousand samples of the source follower MOSFET have been simulated, and the simulation results show that the proposed model has the similar statistical characteristics with the existing models under the effect of the channel length and the density of the oxide trap. Moreover, the noise histogram of the proposed model has been evaluated at different environmental temperatures.