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Finite difference methods are commonly used in the pricing of discretely monitored exotic options in the Black–Scholes framework, but they tend to converge slowly due to discontinuities contained in terminal conditions. We present an effective analytical modification to existing finite difference methods that greatly enhances their performance on discretely monitored options with non-smooth terminal conditions. We apply this modification to the popular Crank–Nicolson method and obtain highly accurate option pricing results with significantly reduced CPU cost. We also introduce an adaptive mesh refinement technique that further improves the computational speed of the modified finite difference method. The proposed method is especially useful for options with high monitoring frequencies, which are difficult to price using other existing methods. [ABSTRACT FROM AUTHOR]

The dispersibility of carbon nanotubes (CNTs) in ultrahigh-performance concrete (UHPC) under different preparation processes was investigated. The dispersion stability, dispersion degree of CNT aggregates, and absorbance of CNT dispersions were measured by static observation, microscope observation, and ultraviolet spectrophotometer. The results showed that compared with adding polycarboxylic acid superplasticizer (SP) after ultrasound, adding SP at the same time as ultrasonic CNT solution obtained a better dispersion of the CNT solution. When the mass ratio of SP to CNT was 1∶1 , the dispersion of CNT suspension was the best under 400-W ultrasonic power for 30 min. The flow properties, setting time, and compressive strength of CNT-modified UHPC also were studied. The experimental results show that the flow performance of CNT-UHPC decreases with the increase of CNT content. The condensation time of CNT-UHPC decreases with the increase of CNT content. The addition of 0.1% by weight CNT can improve the compressive strength of UHPC and refine the microstructure of UHPC. In conclusion, the study results can help to improve the dispersion and stability of carbon nanotubes in UHPC and effectively enhance the strength of UHPC adding carbon nanotubes in terms of working performance, mechanical strength, and microscopic morphology. [ABSTRACT FROM AUTHOR]

In this paper, an adaptive radial basis function neural network (RBFNN) is investigated and presented for identifying the nonlinear dynamical system. In traditional RBFNN structure, the selections of the activated radius are decided by the designer's experience to satisfy the best approximation of nonlinear dynamical function. In order to reduce the experience error, an adaptive RBFNN mechanism that can realize auto-regulation of activated radius is proposed in this paper. Taking the lattice points as the center of activated function, we use Taylor expansion to separate the factor of activated radius in local space. In order to ensure that the identification error has the property of fast convergence, the error conversion function is used for shrinking the gain in the error differential equation. Constructing a Lyapunov function to determine the differential equation of the weights and the activated radius, it is shown that the weights and the activated radius will converge to the neighborhood of its true value and the identification error will converge to neighborhood of zero in a periodic or period-like nonlinear dynamical system. To illustrate the effectiveness of the proposed adaptive RBFNN, Vanderpol and Duffing dynamical system are used as test examples, in comparison with traditional RBFNN and wavelet neural networks (WNN). The results show that the proposed method has best accurate identification and approximating effect in all of test algorithms. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Tumor stroma composing diverse extracellular matrixes (ECM) and stromal cells shapes a condensed physical barrier, which severely hampers the efficient accessibility of nanomedicine to tumor cells, especially these deep‐seated in the core of tumor. Such barrier significantly compromises the antitumor effects of drug‐loaded nanomedicine, revealing the remarkable importance of disrupting stromal barrier for improved tumor therapy with deep penetration ability. To achieve this goal, various nanoparticle‐based strategies have been developed, including direct depleting ECM components via delivering anti‐fibrotic agents or targeting stromal cells to suppress ECM expression, dynamic regulation of nanoparticles' physicochemical properties (i.e., size, surface charge, and morphology), mechanical force‐driven deep penetration, natural/biomimetic self‐driven nanomedicine, and transcytosis‐inducing nanomedicine. All these nanostrategies were systemically summarized in this review, and the design principles for obtaining admirable nanomedicine were included. With the rapid development of nanotechnology, elaborate design of multifunctional nanomedicine provides new opportunities for overcoming the critical stromal barriers to maximize the therapeutic index of various therapies, such as chemotherapy, photodynamic therapy, and immunotherapy. Key Scientists: In 2006, Chan et al. demonstrated that the size and shape of nanoparticles were important for biomedical applications, such as intracellular delivery rate and tissue penetration. In addition, the degradation of the structural collagen was confirmed to increase the diffusion of nanoparticles and macromolecules by Davies et al. in 2010. These findings reveal the importance of chemophysical properties of nanoparticles in determining their diffusion and the critical roles of stromal barrier in hindering nanoparticles penetration. On the basis of this, photoswitchable nanoparticles were developed by Kohane et al. for triggered tissue penetration and efficient drug delivery. In 2015, Nie et al. reported the targeted depletion of cancer‐associated fibroblasts by peptide assembly for enhanced antitumor drug delivery. In 2019, Shen et al. proposed the transcytosis strategy to promote the tumor penetration of nanoparticles. Very recently, Luo et al. reported the specific reversing of the biological function of cancer‐associated fibroblasts to suppress the generation of stromal matrix, greatly increasing the drug perfusion in tumor tissue. All these strategies fueled the design and construction of function‐specific nanoparticles for tumor therapy. [ABSTRACT FROM AUTHOR]

To observe the dynamic changes in the silage corn production, the study was based on panel data from 30 provinces in China from 2001 to 2021, and used a center of gravity model to analyze the changes in the silage corn production agglomeration areas. On this basis, the dynamic spatial Durbin model was used to analyze the impact of factor input, socio-economic and policy support on regional changes in Chinese silage corn production. The results showed that there was a spatial clustering phenomenon in Chinese silage corn, which meant that the Moran index of Chinese silage corn production from 2001 to 2021 showed an overall development trend of 'decreasing-increasing-decreasing- increasing'. The evolution trajectory of the production center showed that the center of gravity in the Chinese silage corn production area showed an evolution trend of 'first northeast, then northwest, and southwest'. The results of the mechanism of action indicated that the main driving factors for promoting the production of silage corn were grain advantages, financial support, and increased income from migrant workers. The production infrastructure, fertilizer application, and agricultural benefits had a positive impact on the production of silage corn in this province, but the impact on the production of silage corn in neighboring provinces was not significant. [ABSTRACT FROM AUTHOR]

Gene therapy is the ultimate therapeutic technology for diseases related to gene abnormality. However, the use of DNA alone has serious problems, such as poor stability and difficulty in entering target cells. The development of a safe and efficient gene delivery system is the cornerstone of gene therapy. Of particular interest, multifunctional peptides are rationally designed as non-viral vectors for efficient gene delivery. As components of gene delivery vectors, these peptides play critically important roles in skeleton construction, the implementation of targeting strategies, cell membrane penetration, endosome rupture, and nuclear transport. In recent years, the research of functional peptide-based gene delivery vectors has made important progress in improving transfection efficiency. The latest research progress and future development direction of peptide-based gene delivery vectors are reviewed in this paper. [ABSTRACT FROM AUTHOR]

The experiment was conducted to investigate the effect of different biological starter treatments and fermentation days on the nutritional value of Chinese medicinal residue after fermentation. Six Chinese medicinal residue were selected in the experiment, and a 4 x 4 two-factor experimental design was adopted. Four levels were set for two experimental factors with different biological starter cultures (control group, complex enzyme group, complex bacteria group and complex enzyme + bacteria group) and fermentation days (3, 6, 9, 12 d), and the changes in nutrient content of Chinese medicinal residue after fermentation were carried out with the interaction of different factors and levels. The results showed that there was extreme interaction between different fermentation treatments and different fermentation days on changes of conventional nutrient content of six kinds of Chinese medicinal residues (P<0.01). The fermentation quality was significantly improved, the fiber content was decreased, and the crude protein content was increased when the composite enzyme powder and composite bacterial powder were added. With the extension of fermentation days, the fermentation quality increased at first and then decreased, and the fermentation effect was similar to that of 3 d after fermentation at 12 d. The study indicates that the suitable starter is mixed treatment group of compound enzyme powder and compound bacterial powder, and the suitable fermentation time is 3 d. [ABSTRACT FROM AUTHOR]

Three new three-dimensional metal–organic frameworks were synthesized based on a naphthalenediimide derivative ligand, all of which exhibit photochromic behaviour due to the presence of the naphthalenediimide core. Interestingly, two of them possess significant colour changes under light, excellent stability, and appropriate photochromic lifetimes, thus showing potential for application in inkless and erasable printing media. [ABSTRACT FROM AUTHOR]

Several stress‐activated signals are highly responsible for the thermal tolerance and attribute to the poor therapeutic outcome of photothermal therapy (PTT). In this study, the naturally human hair‐derived nanoparticles (Hair NPs) with significant photothermal conversion efficacy are explored to combine with stress‐activated signal inhibitors for maximizing the PTT efficiency. During the Hair NPs‐based PTT, two distinct signals are found to be remarkably upregulated. One is the heat‐induced overexpression of HSP90, and the other one is the activation of mitogen‐activated protein kinase (MAPK) signaling pathway. Through the integration of particular inhibitors (17‐allylamino‐17‐demethoxygeldanamycin (17AAG) specifically binding to HSP90 or LY2228820 targeting to p38 MAPK) and the subsequent modification of hyaluronic acid (HA), the resultant Hair NPs‐HA@inhibitor can specifically deliver the inhibitor into tumor cells with minimal side effects on normal tissues, which can specifically block the stressfully activated signals as well as inhibit the expression of their downstream effectors (e.g., MMPs, VEGF) that are closely related with tumor survival and invasion. Without these elements to protect tumor cells or promote tumor progression, the Hair NPs‐induced PTT effect can be much elevated, resulting in a superior antitumor efficacy. These findings represent an effective approach in maximizing PTT effect for fighting against tumor. [ABSTRACT FROM AUTHOR]

In the environment of expansion of college enrollment, the current teaching resources cannot satisfy the requirements of students' learning, which greatly restricts the students' learning interest, especially in the course of automatic control principle. With the development of computer technology and virtual instrument technology, the emergence of virtual laboratory not only provides a beneficial supplement for the traditional experiment, but also extends the experiment without limitation of time and space. Based on the concept of virtual laboratory, a virtual experiment platform is proposed for the course of automatic control principle by applying B/S network architecture and Mysql database in LABview software. The realizations of virtual experiment platform such as remote network design, interface design, basic and innovative experimental contents are further studied in this paper. This virtual experimental platform can provide network remote access for students and offer an online environment for teachers to check experimental results. This platform has completely broken the traditional experimental model and helps students to cultivate creative ability. The characteristic of excellent openness and flexibility can ensure adding new function for future education development in this platform. Further to the observation of the teaching effect of this platform applied in the Nanfang College of Sun Yat-Sen University, students are more willing to accept the automatic control principle course combined with virtual experimental platform. [ABSTRACT FROM AUTHOR]

Yam is an important food staple for millions of people globally, particularly those in the developing countries of West Africa and the Pacific Islands. To sustain the growing population, yam production must be increased amidst the many biotic and abiotic stresses. Plant viruses are among the most detrimental of plant pathogens and have caused great losses of crop yield and quality, including those of yam. Knowledge and understanding of virus biology and ecology are important for the development of diagnostic tools and disease management strategies to combat the spread of yam-infecting viruses. This review aims to highlight current knowledge on key yam-infecting viruses by examining their characteristics, genetic diversity, disease symptoms, diagnostics, and elimination to provide a synopsis for consideration in developing diagnostic strategy and disease management for yam. [ABSTRACT FROM AUTHOR]

Differing from the traditional wavelet neural network, a special type of discrete-time multiscale wavelet neural network (MWNN) using mesh grid is presented and investigated to solve the problem of identification of the autonomous nonlinear dynamical system. Inspired by the multiscale perception of biological neurons and the concept of continuous wavelet theory, multiscale and mesh grid proposed in this paper can be regarded as scale transformation and time translation in the mechanism of MWNN. For the convenience of digital processor realization, discrete-time expressions of weights updating and errors iteration are inferred by the Taylor expansion. In order to ensure the convergence of performance of this discrete-time model, the relation between the constant C in the equation of error iteration and sampling interval has been discovered by applying Z transform theory. The tracking error of autonomous nonlinear dynamical system will converge to the neighborhood of zero, which has been testified by discrete-time Lyapunov stability theory. For comparative purposes, discrete-time MWNN, Raised-Cosine Radial Basis Function Neural Network (RCRBFNN) and Gaussian Radial Basis Function Neural Network (GRBFNN) are used for solving the problem of autonomous nonlinear dynamical system identification. The Lorenz system and clinical electrocardiogram (ECG) dynamical system are applied to test the efficacy and superiority of the proposed discrete-time MWNN, in comparison with GRBFNN and RCRBFNN. [ABSTRACT FROM AUTHOR]

Previous studies have suggested that depression, anxiety, and somatization disorder are strongly associated with diminished functional status. However, research has not tested the mediational models of how depression and anxiety lead to functional impairment. The aim of this study was to examine whether somatization disorder mediates the association of depression and anxiety with functional impairment in heart failure (HF) patients. The self-reported questionnaires were applied to measure depression, anxiety, and somatization disorder. Functional status was evaluated by the NYHA Class. Ordinal logistic regression analysis was performed to examine the association of depression, anxiety, and somatization disorder with functional status. Mediation analysis was conducted to determine indirect effects. Functional impairment was both related to depression (OR = 2.257, 95% CI = 1.534–3.322, P < 0.001) and elevated somatization severity (OR = 1.042, 95% CI = 1.003–1.082, P = 0.032) in HF patients, whereas anxiety was not associated with functional impairment (OR = 0.659, 95% CI = 0.429–1.012, P > 0.05). Mediation analysis indicated that both depression and anxiety have indirect effects on functional impairment as mediated by somatization disorder in HF patients. Additionally, depression has direct effect on functional impairment of the patients. [ABSTRACT FROM AUTHOR]

Type 1 narcolepsy is strongly (98%) associated with human leukocyte antigen (HLA) class II DQA1*01:02/DQB1*06:02 (DQ0602) and highly associated with T cell receptor (TCR) alpha locus polymorphism as well as other immune regulatory loci. Increased incidence of narcolepsy was detected following the 2009 H1N1 pandemic and linked to Pandemrix vaccination, strongly supporting that narcolepsy is an autoimmune disorder. Although recent results suggest CD4+ T cell reactivity to neuropeptide hypocretin/orexin and cross-reactive flu peptide is involved, identification of other autoantigens has remained elusive. Here we study whether autoimmunity directed against Regulatory Factor X4 (RFX4), a protein co-localized with hypocretin, is involved in some cases of narcolepsy. Studying human serum, we found that autoantibodies against RFX4 were rare. Using RFX4 peptides bound to DQ0602 tetramers, antigen RFX4-86, -95, and -60 specific human CD4+ T cells were detected in 4/10 patients and 2 unaffected siblings, but not in others. Following culture with each cognate peptide, enriched autoreactive TCRαβ clones were isolated by single-cell sorting and TCR sequenced. Homologous clones bearing TRBV4-2 and recognizing RFX4-86 in patients and one twin control of patient were identified. These results suggest the involvement of RFX4 CD4+ T cell autoreactivity in some cases of narcolepsy, but also in healthy donors. [ABSTRACT FROM AUTHOR]

This paper presents an airborne piezoelectric micromachined ultrasonic transducers (PMUTs) operated at low frequency (40–50 kHz) for long-range detection, where the acoustic absorption loss in air is relatively low (0.8–1 dB/m). The PMUTs made with single-crystal Lead Zirconate Titanate (PZT) enables a high piezoelectric coefficient (${e} _{31, f} \approx ~16$ - 24 C/ $\text{m}^{{2}}$), and a low dielectric constant ($\varepsilon _{\mathrm {r}}~\approx ~308$), achieving high PMUT transceiver efficiency. The $2\times 2$ PMUT array achieves a very high sound pressure level (SPL) output of 109.4 dB at 26 cm distance. Different from conventional PZT PMUTs, this study utilized single-crystal PZT with a low permittivity to achieve a good acoustic reception, demonstrating the sensitivity of 2 mV/Pa. This work reports the PMUT design, modeling, fabrication, characterization, enabling a long-range detection of 4.8 meters in a pulse-echo experiment, which was conducted by a pair of $2\times 2$ PMUT arrays with the matched resonances. [2020-0270] [ABSTRACT FROM AUTHOR]

Cell primitive-based functional materials that combine the advantages of natural substances and nanotechnology have emerged as attractive therapeutic agents for cancer therapy. Cell primitives are characterized by distinctive biological functions, such as long-term circulation, tumor specific targeting, immune modulation etc. Moreover, synthetic nanomaterials featuring unique physical/chemical properties have been widely used as effective drug delivery vehicles or anticancer agents to treat cancer. The combination of these two kinds of materials will catalyze the generation of innovative biomaterials with multiple functions, high biocompatibility and negligible immunogenicity for precise cancer therapy. In this review, we summarize the most recent advances in the development of cell primitive-based functional materials for cancer therapy. Different cell primitives, including bacteria, phages, cells, cell membranes, and other bioactive substances are introduced with their unique bioactive functions, and strategies in combining with synthetic materials, especially nanoparticulate systems, for the construction of function-enhanced biomaterials are also summarized. Furthermore, foreseeable challenges and future perspectives are also included for the future research direction in this field. [ABSTRACT FROM AUTHOR]

This communication presents a magnetic-material-loaded 3-D frequency-selective rasorber (FSR) consisting of independent transmission and absorption channels. The main feature of the proposed design is employing both ferrite material and meander line in the absorption channel to obtain a wide absorption band and low-loss transmission band. Detailed analysis of the absorption channel is given with the help of equivalent circuit models to demonstrate the operating principle. The design guidelines are formulated, and a design example is presented with both the simulated and measured results. The proposed FSR features both thin thickness and wide absorption bands. Moreover, no lumped components are required, which greatly facilitates the fabrication and reduces the cost. [ABSTRACT FROM AUTHOR]

A three-dimensional (3-D) structure is proposed in this article for ultra-wideband absorber design. The ultra-wideband absorber is implemented by properly combining two subabsorbers. The first subabsorber operates in its fundamental mode ($f_{0}$) and the third-order mode ($3f_{0}$). Its lossy layer is designed with an infinite impedance at the second-order mode frequency ($2f_{0}$). The second subabsorber is designed to operate in its fundamental mode frequency, which is corresponding to $2f_{0}$ of the first subabsorber. A double-sided parallel-strip line (DSPSL) is employed to produce the required infinite impedance of the first absorber. A simple equivalent circuit model of the DSPSL is established to explain the operating principle. A conventional parallel LC circuit is also provided for comparison to show the advantages of the DSPSL. Single-polarized and dual-polarized ultra-wideband absorbers are designed by combining these two subabsorbers, and their simulated fractional bandwidths (FBWs) of 151.6% and 150.9% are achieved, respectively. A prototype of the dual-polarized ultra-wideband absorber is fabricated and measured to validate the design concept. Its measured absorption band from 1.50 to 12.31 GHz with an FBW of 156.6% is in a good agreement with the simulated one. The proposed absorber features a wide absorption band and few lumped elements, which makes it more useful in practical applications. [ABSTRACT FROM AUTHOR]

SiO2 particles and red-emitting CaMgSi2O6:Eu2+,Mn2+ phosphor have been added into a yellow phosphor compound YAG:Ce3+ to enhance the optical efficiency of white light LEDs whose average correlated color temperature (CCT) is in the range of 5600 K ÷ 8500 K. It was observed that altering CaMgSi2O6:Eu2+,Mn2+ concentration from 2 % to 30 % while maintaining 5 % of the SiO2 strongly influenced the color rendering index (CRI), color quality scale (CQS), and lumen efficiency of the compound. Besides, through the application of Monte Carlo simulation and Mie-scattering theory, it was possible to improve the optical properties by CaMgSi2O6:Eu2+,Mn2+ and SiO2 addition. The results provided a practical approach to achieve higher luminous efficiency and better color uniformity in remote-phosphor white LEDs (RP-WLEDs). [ABSTRACT FROM AUTHOR]

All‐DNA scaffolds act as templates for the organization of photosystem I model systems. A series of DNA templates composed of ZnII‐protoporphyrin IX (ZnIIPPIX)‐functionalized G‐quadruplex conjugated to the 3′‐ or 5′‐end of the tyrosinamide (TA) aptamer and ZnIIPPIX/G‐quadruplex linked to the 3′‐ and 5′‐ends of the TA aptamer through a four‐thymidine bridge. Effective photoinduced electron transfer (ET) from ZnIIPPIX/G‐quadruplex to bipyridinium‐functionalized tyrosinamide, TA‐MV2+, bound to the TA aptamer units is demonstrated. The effectiveness of the primary ET quenching of ZnIIPPIX/G‐quadruplex by TA‐MV2+ controls the efficiency of the generation of TA‐MV+.. The photosystem‐controlled formation of TA‐MV+. by the different photosystems dictates the secondary activation of the ET cascade corresponding to the ferredoxin‐NADP+ reductase (FNR)‐catalysed reduction of NADP+ to NADPH by TA‐MV+. and the sequestered alcohol dehydrogenase catalysed reduction of acetophenone to 1‐phenylethanol by NADPH. [ABSTRACT FROM AUTHOR]

All‐DNA scaffolds act as templates for the organization of photosystem I model systems. A series of DNA templates composed of ZnII‐protoporphyrin IX (ZnIIPPIX)‐functionalized G‐quadruplex conjugated to the 3′‐ or 5′‐end of the tyrosinamide (TA) aptamer and ZnIIPPIX/G‐quadruplex linked to the 3′‐ and 5′‐ends of the TA aptamer through a four‐thymidine bridge. Effective photoinduced electron transfer (ET) from ZnIIPPIX/G‐quadruplex to bipyridinium‐functionalized tyrosinamide, TA‐MV2+, bound to the TA aptamer units is demonstrated. The effectiveness of the primary ET quenching of ZnIIPPIX/G‐quadruplex by TA‐MV2+ controls the efficiency of the generation of TA‐MV+.. The photosystem‐controlled formation of TA‐MV+. by the different photosystems dictates the secondary activation of the ET cascade corresponding to the ferredoxin‐NADP+ reductase (FNR)‐catalysed reduction of NADP+ to NADPH by TA‐MV+. and the sequestered alcohol dehydrogenase catalysed reduction of acetophenone to 1‐phenylethanol by NADPH. [ABSTRACT FROM AUTHOR]

In this paper, we present to achieve a broadband miniaturized transmission waveguide based on complementary spoof surface plasmon polaritons (CSSPPs). For this purpose, a novel SSPP design that consists of a corrugated slot line and a group of additional interdigital structures (ISs) is proposed, which brings in an extra solution to control the cut-off property of CSSPPs. The transmission cut-off frequency of the proposed design decreases with the increasing of the number of the ISs. Since the width of CSSPP waveguide is directly related to the operating frequency, the degree of miniaturization can be modulated freely by carefully choosing the number of the ISs. A prototype of device with four-ISs introduced is designed and fabricated. And the cut-off frequency of the design decreases from 10 GHz to 5.3 GHz, when the ISs are added. Experimental results agree well with the numerical simulations. The proposed design illustrates great potentials in modern plasmonic integrated circuits. [ABSTRACT FROM AUTHOR]

This study develops a differential‐fed filtering patch antenna, which features superior frequency selectivity, compact size, low cross‐polarisation, and symmetrical radiation patterns. The proposed antenna consists of a rectangular patch on the top layer, which is differentially fed by a balun bandpass filter on the bottom layer. A pair of rectangular coupling slots were etched on the middle layer for energy coupling. The patch antenna performs not only as the radiator but also as the last resonator of the whole filter circuit for compactness. A prototype of the proposed filtering antenna operating at 2.45 GHz was fabricated and tested. The measured in‐band peak gain is 5.9 dBi with steep roll‐off at band edges, and the out‐of‐band gain is less than − 25 dBi. Moreover, symmetrical radiation patterns and low cross‐polarisation levels of − 22 dB are also realised for the proposed filtering antenna. [ABSTRACT FROM AUTHOR]

A novel dual-polarized band-absorptive frequency selective rasorber (FSR) is proposed in this communication. The FSR is constructed by two-layer cascaded printed circuit boards, in which meander-line square loops with and without lumped resistors loaded on the top and bottom surfaces of the two substrates. Its operating principle is analyzed, and an accurate equivalent circuit model is presented. A prototype has been fabricated, assembled, and measured. The measured absorption band is from 4.8 to 6.81 GHz (34.6%), with a thickness of $\lambda _{\mathrm {a}}$ /8 at 4.8 GHz. Moreover, it is almost transparent to electromagnetic waves below 1.54 GHz. The measurement results achieve a good agreement with the simulated results, which verifies the effectiveness of the design. [ABSTRACT FROM AUTHOR]

Abstract A horizontally polarized (HP) wideband antenna is designed and analyzed for wireless communication in this communication. The HP antenna is a combination of four quarter-wavelength slot elements, and fed by a wideband power divider with equal amplitude and zero phase difference output signals. Equivalent to the current loop, four slot elements rotate around the center of proposed structure, which gives rise to a monopolar radiation pattern. A prototype is designed, fabricated and measured. The results show that a deep null more than 20 dB appears in the broadside of the elevation plane radiation pattern. And a small ripple less than 2 dB in azimuth plane radiation pattern is obtained. The antenna has a wide impedance band of 33.3% for S11 <−10 dB and a cross-polarization level lower than 15 dB. [ABSTRACT FROM AUTHOR]

Highlights • A variation of the FRI-based DOA estimation algorithm under closely-spaced sources, low SNR, and small number of snapshots scenarios is proposed. • The MMV-FRI model is built in the direct data domain, which makes the new method be free of model residual error and compatible with coherent sources. • The full column rank constraint on the mapping matrix in FRIDA is relaxed, which reduces the Bessel approximation error to a negligible level. • For FRI iteration, only a single straightforward initialization is used instead of the multiple random initializations. Abstract Recently, a new DOA estimation algorithm called FRIDA was proposed. It is based on spatial finite rate of innovation (FRI) reconstruction and exhibits some attractive features. In this paper, we propose a variation of FRIDA which is called FRIDA-V (suffix “-V” means variation). FRIDA-V improves FRIDA in three aspects. Firstly, a multiple measurement vectors (MMV) spatial FRI model is built in the direct data domain rather than the covariance domain, which avoids the model residual error in FRIDA and makes the new method capable of handling both incoherent and coherent sources. Secondly, the full column rank constraint on the mapping matrix is relaxed by adopting the pseudo-inverse technique, which makes it possible to reduce the Bessel function approximation error to a negligible level. Thirdly, the multiple random initializations in the iterative calculations are replaced by a single straightforward initialization, which will speed up the convergence to the optimal solution and save the computational resource. Theoretical derivations and numerical simulation results are given to demonstrate the effectiveness of the proposed method. Compared with the representative methods, the new method is gridless and possesses higher performance with closely-spaced sources and under low signal-to-noise ratio (SNR), small number of snapshots scenarios. [ABSTRACT FROM AUTHOR]

Allylic N,N-acetals are important intermediates in the synthesis of biologically active heterocycles and natural products. Herein, we report a facile protocol for the synthesis of this compound through N-iodosuccinimide-mediated hydroamination of allenamides by imidazole heterocycles. The reaction is regioselective, fast, and tolerant of a broad scope of imidazole and benzimidazole derivatives. The key intermediate is a conjugated sulfimide ion species that undergoes nucleophilic attack by imidazole to form the 1,2-adduct. Mixtures of N1- and N3-substituted isomers were obtained using asymmetrically substituted imidazoles. However, the 1,4-adduct was obtained using a tri-substituted imidazole. The efficiency of the gram-scale reaction suggests the potential industrial application of this synthetic method. [ABSTRACT FROM AUTHOR]

The influence of mineral admixtures and curing conditions on the permeability of concrete with high volume mineral admixtures is investigated. Fly ash and ground granulated blast furnace slag (GGBFS) are used to replace 50% cement, the water absorption, capillary water absorption, sorptivity coefficient, electric flux and carbonation depth of concrete with mineral admixtures are tested under different curing conditions, such as the curing time, curing humidity and curing temperature. The test results show that the water absorption, capillary water absorption, sorptivity coefficient, electric flux and carbonation depth of concrete decrease with the longer standard curing time, higher curing humidity and appropriate curing temperature, and decrease with the increasing of GGBFS content. It is also shown that the permeability of concrete with high volume mineral admixtures is very sensitive to the curing conditions. [ABSTRACT FROM AUTHOR]

The present study was performed to investigate the chemical components of the branches and leaves of Isodon rubescens. Two 6,7-seco-spiro-lacton-ent-kauranoids were obtained. Based on the extensive spectroscopic analyses, their structures were elucidated as 6-epi-11-O-acetylangustifolin (1) and 11-O-acetylangustifolin (2), respectively. The structure of 2 was further comfirmed by X-ray crystallography analysis. MTT method was employed to evaluate their cytotoxity against human lung cancer cell lines A549 and leukemia cell lines K562. [ABSTRACT FROM AUTHOR]

• We propose the self-information of radicals (SIR) from the information theory perspective to measure the importance of radicals in recognizing Chinese characters. • The proposed SIR can be easily adopted by two commonly used radical-based zero-shot Chinese Character Recognition (ZSCCR) frameworks, i.e., sequence matching based and attribute embedding based. • For sequence matching based ZSCCR, we propose a novel Chinese character uncertainty elimination (CUE) framework, which is capable of alleviating the sequence mismatch problem. • For attribute embedding based ZSCCR, we propose a novel radical information embedding (RIE) method, which can highlight the importance of indispensable radicals. • Comprehensive experiments on the CASIA-HWDB, ICDAR2013, CTW, and AHCDB datasets demonstrate the effectiveness and high extensibility of the proposed SIR. Zero-shot Chinese character recognition (ZSCCR) is an important research topic in Chinese character recognition as it attempts to recognize unseen Chinese characters. As basic components and mid-level representations, radicals are significant for ZSCCR. However, previous methods treat the importance of radicals equally, ignoring the different contributions of radicals in distinguishing characters. In this paper, we propose the self-information of radicals (SIR) to measure the importance of radicals in recognizing Chinese characters. The proposed SIR can be easily adopted by two commonly used radical-based ZSCCR frameworks, i.e., sequence matching based and attribute embedding based. For sequence matching based ZSCCR, we propose a novel Chinese character uncertainty elimination (CUE) framework to alleviate the radical sequence mismatch problem. For attribute embedding based ZSCCR, we propose a novel radical information embedding (RIE) method that can highlight the importance of indispensable radicals and weaken the influence of some unnecessary radicals. We conducted comprehensive experiments on the CASIA-HWDB, ICDAR2013, CTW datasets, and AHCDB datasets to evaluate the proposed method. Experiments show that our proposed methods can achieve superior performance to the state-of-the-art methods, which demonstrate the effectiveness and the high extensibility of the proposed SIR. [ABSTRACT FROM AUTHOR]

Background: A recent publication suggested molecular mimicry of a nucleoprotein (NP) sequence from A/Puerto Rico/8/1934 (PR8) strain, the backbone used in the construction of the reassortant strain X-179A that was used in Pandemrix® vaccine, and reported on anti-hypocretin (HCRT) receptor 2 (anti-HCRTR2) autoantibodies in narcolepsy, mostly in post Pandemrix® narcolepsy cases (17 of 20 sera). In this study, we re-examined this hypothesis through mass spectrometry (MS) characterization of Pandemrix®, and two other pandemic H1N1 (pH1N1)-2009 vaccines, Arepanrix® and Focetria®, and analyzed anti-HCRTR2 autoantibodies in narcolepsy patients and controls using three independent strategies. Methods: MS characterization of Pandemrix® (2 batches), Arepanrix® (4 batches) and Focetria® (1 batch) was conducted with mapping of NP 116I or 116M spectrogram. Two sets of narcolepsy cases and controls were used: 40 post Pandemrix® narcolepsy (PP-N) cases and 18 age-matched post Pandemrix® controls (PP-C), and 48 recent (≤6 months) early onset narcolepsy (EO-N) cases and 70 age-matched other controls (O-C). Anti-HCRTR2 autoantibodies were detected using three strategies: (1) Human embryonic kidney (HEK) 293T cells with transient expression of HCRTR2 were stained with human sera and then analyzed by flow cytometer; (2) In vitro translation of [35S]-radiolabelled HCRTR2 was incubated with human sera and immune complexes of autoantibody and [35S]-radiolabelled HCRTR2 were quantified using a radioligand-binding assay; (3) Optical density (OD) at 450 nm (OD450) of human serum immunoglobulin G (IgG) binding to HCRTR2 stably expressed in Chinese hamster ovary (CHO)-K1 cell line was measured using an in-cell enzyme-linked immunosorbent assay (ELISA). Results: NP 116M mutations were predominantly present in all batches of Pandemrix®, Arepanrix® and Focetria®. The wild-type NP109-123 (ILYDKEEIRRIWRQA), a mimic to HCRTR234-45 (YDDEEFLRYLWR), was not found to bind to DQ0602. Three or four subjects were found positive for anti-HCRTR2 autoantibodies using two strategies or the third one, respectively. None of the post Pandemrix® narcolepsy cases (0 of 40 sera) was found positive with all three strategies. Conclusion: Anti-HCRTR2 autoantibody is not a significant biological feature of narcolepsy or of post Pandemrix® autoimmune responses. [ABSTRACT FROM AUTHOR]

Poor tumor selectivity and short life span of reactive oxygen species (ROS) are two major challenges in photodynamic therapy (PDT). In this study, a selftransformable pH-driven membrane anchoring photosensitizer (pHMAPS) is used to realize tumor-specific accumulation and in situ PDT on tumor cell membrane to maximize the therapeutic potency. It is found that pHMAPS was able to form α-helix structure under acidic condition (pH 6.5 or 5.5), while remain random coil at normal pH of 7.4. This pH-driven secondary structure switch enables the successful insertion of pHMAPS into membrane lipid bilayer, especially for cancerous cell membrane in the acidic tumor microenvironment. Under laser irradiation, cytotoxic ROS is generated in the immediate vicinity of cell membrane, resulting in superior cell killing effect in vitro and significant inhibition of tumor growth in vivo. Importantly, benefited from this membrane-specific PDT, tumor growth-induced hepatic, pulmonary, as well as osseous metastases of breast cancer cells are also retarded after PDT treatment. Thus, the membrane localized PDT by pHMAPS provides a simple but effective strategy to enhance the medical performance of photosensitizing agents in cancer therapy. [ABSTRACT FROM AUTHOR]

Poor tumor selectivity and short life span of reactive oxygen species (ROS) are two major challenges in photodynamic therapy (PDT). In this study, a self-transformable pH-driven membrane anchoring photosensitizer (pHMAPS) is used to realize tumor-specific accumulation and in situ PDT on tumor cell membrane to maximize the therapeutic potency. It is found that pHMAPS was able to form α-helix structure under acidic condition (pH 6.5 or 5.5), while remain random coil at normal pH of 7.4. This pH-driven secondary structure switch enables the successful insertion of pHMAPS into membrane lipid bilayer, especially for cancerous cell membrane in the acidic tumor microenvironment. Under laser irradiation, cytotoxic ROS is generated in the immediate vicinity of cell membrane, resulting in superior cell killing effect in vitro and significant inhibition of tumor growth in vivo. Importantly, benefited from this membrane-specific PDT, tumor growth-induced hepatic, pulmonary, as well as osseous metastases of breast cancer cells are also retarded after PDT treatment. Thus, the membrane localized PDT by pHMAPS provides a simple but effective strategy to enhance the medical performance of photosensitizing agents in cancer therapy. [ABSTRACT FROM AUTHOR]

Supramolecular photosensitizers (supraPSs) have emerged as effective photodynamic therapy (PDT) agents. Here, we propose the assembling capacity of supraPSs as a new strategy to construct theranostic nanoplatform with versatile functions aming at high-performance tumor therapy. By coating tirapazamine (TPZ)-loaded mesoporous silica nanoparticles (MSNs) with layer-by-layer (LbL) assembled multilayer, the versatile nanoplatform (TPZ@MCMSN-Gd 3+ ) was obtained with the formation of supraPSs via host-guest interaction and the chelation with paramagnetic Gd 3+ . The TPZ@MCMSN-Gd 3+ could be specifically uptaken by CD44 receptor overexpressed tumor cells and respond to hyaluronidase (HAase) to trigger the release of therapeutics. As confirmed by in vivo studies, TPZ@MCMSN-Gd 3+ showed preferential accumulation in tumor site and significantly inhibited the tumor progression by the collaboration of PDT and bioreductive chemotherapy under NIR fluorescence/MR imaging guidance. Taken together, this supraPSs based strategy paves a new paradigm of the way for the construction of theranostic nanoplatform. [ABSTRACT FROM AUTHOR]

This letter proposes a broadband mono‐cone antenna with a shorted parasitic ring and parasitic metal pillars. Four parasitic metal pillars expand the high‐frequency operation band, while a shorted parasitic ring increases the current flow path and expands the low‐frequency operation band. A 148.3% impedance bandwidth for VSWR ≤ 2 from 0.831 to 5.6 GHz is attained. The antenna has stable radiation performance across the entire operation spectrum. The simulated and measured results show a good agreement. It is exceptionally compatible with GSM900, DCS1800, PCS1900, UMTS, IMT2000, WiBro, WiMAX2350/3500, LPWAN, wireless LAN (IEEE 802.11b), and a portion of the WLAN/Wi‐Fi frequency spectrum. Indoor applications such as wireless energy collection, partial discharge detection, and so on are possible for the proposed antenna. [ABSTRACT FROM AUTHOR]

A core‐shell structured Pd@TS‐1@meso‐SiO2 catalyst with confined Pd nanometals has been fabricated by one‐pot synthesis, impregnation method and sol‐gel method. With the promotion of acid sites and protection of mesoporous silica shell, Pd@TS‐1@meso‐SiO2 shows higher activity than commercial comparison and higher stability than sample without mesoporous silica shell in the hydrogenation of nitrobenzene. The schematic illustration of the synergy effect is also proposed. [ABSTRACT FROM AUTHOR]

ABSTRACT A novel ultra-wideband (UWB) antenna with chessboard-shaped patch is successfully designed by employing planar patterned metamaterial in this paper. The metamaterial antenna has two layers, a novel chessboard-shaped patch on the top layer and a planar metallic ground carved grid patterned gaps on the bottom layer. This novel antenna has a fractional impedance bandwidth of 71%, which is far more than that of a corresponding conventional patch antenna. Its radiation efficiency is higher than 88% within its operating frequency range 3.5∼7.9GHz and a maximum radiation efficiency of 96% has been achieved. Its gain is varied from 2.7 to 6.9dBi within its operating bandwidth. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:3008-3012, 2016 [ABSTRACT FROM AUTHOR]

The PV Industry is a strategic emerging industry in China. With extensive application, easy local accommodation and little impact on the power grid, distributed PV power generation is viewed as a major way of PV power generation in the future. In recent two years, the Chinese government has rolled out policies concerning distributed PV power generation, in the hope to quickly expand the domestic market, ease the impact on the PV industry from global market fluctuations and reduce the excess capacity of the PV industry. However, distributed PV power generation faces complex financing problems at home with the unclear definition of rooftop property rights, risks in PV power generation policies, risks in the access to power grids and uncertainties in profitability. The paper summarizes that China must improve laws, polices and management institution to dissolve the financing risks related to distributed PV power generation. [ABSTRACT FROM AUTHOR]

To integrate treatments of photothermal therapy, photodynamic therapy (PDT), and chemotherapy, this study reports on a multifunctional nanocomposite based on mesoporous silica-coated gold nanorod for high-performance oncotherapy. Gold nanorod core is used as the hyperthermal agent and mesoporous silica shell is used as the reservoir of photosensitizer (Al(III) phthalocyanine chloride tetrasulfonic acid, AlPcS4). The mesoporous silica shell is modified with β-cyclodextrin (β-CD) gatekeeper via redox-cleavable Pt(IV) complex for controlled drug release. Furthermore, tumor targeting ligand (lactobionic acid, LA) and long-circulating poly(ethylene glycol) chain are introduced via host-guest interaction. It is found that the nanocomposite can specifically target to hepatoma cells by virtue of the LA targeting moiety. Due to the abundant existence of reducing agents within tumor cells, β-CD can be removed by reducing the Pt(IV) complex to active cisplatin drug for chemotherapy, along with the releasing of entrapped AlPcS4 for effective PDT. As confirmed by in vitro and in vivo studies, the nanocomposite exhibits an obvious near-infrared induced thermal effect, which significantly improves the PDT and chemotherapy efficiency, resulting in a superadditive therapeutic effect. This collaborative strategy paves the way toward high-performance nanotherapeutics with a superior antitumor efficacy and much reduced side effects. [ABSTRACT FROM AUTHOR]

[Display omitted] • The first PTAA-based tin perovskite solar cells. • The hydrophobic surface of PTAA is modified to become hydrophilic via PEAI. • Two-step fabrication approach was implemented to retard crystal growth. • The PTAA device attained 8.3 % which outperforms that made of PEDOT:PSS. • The long-term stability is significantly improved due to the hydrophobic nature of PTAA. We deposited a smooth and uniform tin-perovskite layer on a hydrophobic conducting polymer, (bis (4-phenyl) (2,4,6-trimethylphenylamine) (PTAA), on modification of the PTAA surface with an organic ammonium salt, phenylethylammonium iodide (PEAI), according to a two-step approach. We found that π-π interaction between the phenyl rings of PTAA and PEAI plays an important role to modify the hydrophobicity of the PTAA surface and to passivate the crystal surface so as to form a tin-perovskite film of high quality. The FASnI 3 device with PTAA serving as a hole-transport layer (HTL) attained PCE 8.3 % with great stability, becoming the first example reported for a PTAA-based tin-perovskite solar cell. Our approach is applicable to other prospective HTL materials to match the energy levels between perovskite and HTL so as to enhance further the performance of the device. [ABSTRACT FROM AUTHOR]

In this paper, a multifunctional theranostic magnetic mesoporous silica nanoparticle (MMSN) with magnetic core was developed for magnetic-enhanced tumor-targeted MR imaging and precise therapy. The gatekeeper β-cyclodextrin (β-CD) was immobilized on the surface of mesoporous silica shell via platinum(IV) prodrug linking for reduction-triggered intracellular drug release. Then Arg-Gly-Asp (RGD) peptide ligand was further introduced onto the gatekeeper β-CD via host–guest interaction for cancer targeting purpose. After active-targeting endocytosis by cancer cells, platinum(IV) prodrug in MMSNs would be restored to active platinum(II) drug in response to the innative reducing microenvironment in cancer cells, resulting in the detachment of β-CD gatekeeper and thus simultaneously triggering the in situ release of anticancer drug doxorubicin (DOX) entrapped in the MMSNs to kill cancer cells. It was found that with the aid of an external magnetic field, drug loaded MMSNs showed high contrast in MR imaging in vivo and exhibited magnetically enhanced accumulation in the cancer site, leading to significant inhibition of cancer growth with minimal side effects. This multifunctional MMSN will find great potential as a theranostic nanoplatform for cancer treatment. [ABSTRACT FROM AUTHOR]

Since 2010 China has faced a worrying phenomenon “wind curtailment” in the development and operation of the wind power industry. This phenomenon has resulted in sharp decline of the utilization hours of the wind power equipment, seriously affected the economic benefits of the wind farms and caused serious energy waste. The wind curtailment in China is seemingly caused by the volatility of the wind power technical characteristics. However, judging from a deep level, the planning, networking management and policies play a critical role. With analysis this paper makes such a conclusion: it is not practical to solve the wind curtailment of China solely with the technical solutions and comprehensive measures must be taken. The paper offers strategies from the planning, policy and technical levels to solve the wind curtailment problem according to the actual situation of China and by referring to experiences of developed countries. [ABSTRACT FROM AUTHOR]

Three Mo8- and Mo12-based polyoxoanion compounds (1–3), containing [Mo8O26]4− and [(SiO4)(Mo12O36)]4− anions, were successfully synthesized by a one-pot hydrothermal method, and structurally characterized by an X-ray crystallographic method. 1, [Cu(L′)4]2[Mo8O26] (L′ = 1-methyl-imidazole), contained rarely observed Mo8-based oblate shell [Mo8O26]4− polyoxoanion, 2, [L′′H]4[SiMo12O40]·5[L′′]·5H2O (L′′ = benzotriazole), and 3, [L′′H]4[SiMo12O40]·2H2O, contained Mo12-based spherical shell α-Keggin [(SiO4)(Mo12O36)]4− polyoxoanions. Interestingly, SiO44− fragment is disordered in 2 but is ordered in 3. The observation that 1–3 have different polyoxoanion structures but crystallize in order in the same solution system is rare for POM synthetic chemistry, and is of interest for understanding the formation mechanism and self-assembly process of Mo-based polyoxoanions. Fragment analysis based on the clathrate structural model, i.e. [Mo8O26]4− anion modeled as [MoO4]24−@Mo6O18, and [(SiO4)(Mo12O36)]4− anion modeled as [SiO4]4−@[Mo12O36] and/or [SiO4]4−@[Mo3O9]2@[Mo6O18], and orbital interaction analysis based on extended Hückel theory calculation were employed successfully to account for the formation mechanism and self-assembly process of fragments and two Mo-based polyoxoanions in 1–3. The calculated large charge transfer and/or high electronic polarization between fragments provide electronic structural information on structural stability and help to interpret the fragment–fragment self-assembly process. [ABSTRACT FROM AUTHOR]

Activity-guided fractionation ofNeosinocalamus affinisleaves led to obtain two new flavonoids, 4′-O-((7″R,8″S)-8″-guaiacylglyceryl)-pleioside B (9) and apigenin 6-C-β-d-fucopyranosyl-7-O-β-d-glucopyranoside (10) along with eight known compounds. Their structures were elucidated on the basis of spectroscopic data (UV, IR, NMR, and MS). Among these 10 compounds, farobin A (4) and isoorientin (7) showed significant antioxidant activity evaluated by 1,1-diphenyl-2-picrylhydrazyl, 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid), superoxide anion and nitric oxide (NO) radical-scavenging assays. [ABSTRACT FROM AUTHOR]

The μνSSM, one of supersymmetric extensions beyond the Standard Model, introduces three singlet right-handed neutrino superfields to solve the μ problem and can generate three tiny Majorana neutrino masses through the seesaw mechanism. In this paper, we investigate the rare decay process in the μνSSM, under a minimal flavor violating assumption for the soft breaking terms. Constrained by the SM-like Higgs with mass around 125 GeV, the numerical results show that the new physics can fit the experimental data for and further constrain the parameter space. [ABSTRACT FROM AUTHOR]

Abstract: A multi-center population-based study in Shanghai, China was performed to explore the implications for the management of pancreatic cancer by comparing diagnosis and survival rates. Novel imaging modalities including MRI (13.9%), PET/CT (1.8%), and EUS (5.6%) were not widely used in our population. Only 39.7% of cases were histologically verified (surgery with histologic diagnosis 31.0%, cytological diagnosis 8.7%, surgery without histologic diagnosis 12.1%, and clinical diagnosis 48.2%). Overall, 30.0% of patients underwent curative-intent operation, and only 9.8% of patients received comprehensive treatment. The prognosis of pancreatic cancer patients was significantly better for patients who were treated in high-volume centers than in low-volume centers. We propose that more effort should be put on novel diagnostic modalities, histological confirmation, and comprehensive treatment in China. Multidisciplinary teams specialized in pancreatic cancer therapy in high-volume centers are urgently needed. [Copyright &y& Elsevier]

Abstract: Bees Algorithm is a population-based method that is a computational bound algorithm whose inspired by the natural behavior of honey bees to finds a near-optimal solution for the search problem. Recently, many parallel swarm based algorithms have been developed for running on GPU (Graphic Processing Unit). Since nowadays developing a parallel Bee Algorithm running on the GPU becomes very important. In this paper, we extend the Bees Algorithm (CUBA (i.e. CUDA based Bees Algorithm)) in order to be run on the CUDA (Compute Unified Device Architecture). CUBA (CUDA based Bees Algorithm). We evaluate the performance of CUBA by conducting some experiments based on numerous famous optimization problems. Results show that CUBA significantly outperforms standard Bees Algorithm in numerous different optimization problems. [Copyright &y& Elsevier]

• Many popular exotic options are path-dependent and have early-exercise features. • Most path-dependent exotic options are discretely monitored and need to be priced using numerical techniques. • Traditional pricing methods such as Monte-Carlo simulations or finite difference methods are easy to implement but are often too slow. • More advanced pricing methods tend to be more efficient but are often too difficult to understand and to properly implement. • Our new quadrature-based method is very efficient while at the same time is very easy to understand and implement. We present a simple, fast, and accurate method for pricing a variety of discretely monitored options in the Black-Scholes framework, including autocallable structured products, single and double barrier options, and Bermudan options. The method is based on a quadrature technique, and it employs only elementary calculations and a fixed one-dimensional uniform grid. The convergence rate is O (1 / N 4) and the complexity is O (M N log N) , where N is the number of grid points and M is the number of observation dates. Besides Black-Scholes, our method is also applicable to more general frameworks such as Merton's jump diffusion model. [ABSTRACT FROM AUTHOR]

Aminopeptidase N (APN/CD13) plays an important role in the growth and metastasis, of tumor, and is a potential biomarker for the post-treatment surveillance of cancer reoccurrence and progression of various malignancies. Thus, we have designed and prepared a convenient and ultrasensitive APN-targeting activity-based ratiometric electrochemical molecular substrate (Ala-AFC) for direct real-time monitoring of APN activity in biosamples. The APN in our experiment was used to hydrolyze the alanine moiety of the Ala-AFC probe and, as a result of this hydrolysis, realize concomitantly a cascade reaction to unmask the electrochemical reporter N-alkylated amino ferrocene (AAF). The Ala-AFC probe exhibited high sensitivity with a wide detection range of 0.05–110 ng mL-1 and a low limit of detection of 23.18 pg mL-1. The electrochemical signals were found to be distinctly specific for APN and free of interference from other electroactive biological species. Furthermore, the Ala-AFC probe was employed to monitor and quantify, in real-time, the activity of APN in tumor cells, whole blood, and urine. In addition, the results of our direct electrochemical quantifications of the amount of APN in whole blood and urine were found to be consistent with the results of the use of commercially available fluorometric assay kits to sense APN in serum and urine. Thus our approach shows promise as a point-of-care tool for cancer diagnostics and post-treatment surveillance of cancer reoccurrence. [ABSTRACT FROM AUTHOR]