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Kaempferol-3-O-rutinoside (KR) is a flavonoid glycoside derived from traditional Chinese medicine, plants, and tea, and has good myocardial protection. This study focuses on the mechanism of myocardial protection with KR and whether myocardial protection can be achieved by activating the adenosine monophosphate-activated protein kinase–silent mating-type information regulation 2 homolog 1 (sirtuin) (AMPK/SIRT1) signal pathway. Molecular docking technique was used to predict the binding affinity of KR to AMPK. The inflammatory injury model of H9c2 cells was established by lipopolysaccharide (LPS) induction. H9c2 cell proliferation was detected by cell counting kit-8 assay. The apoptosis rate was measured by flow cytometry. Levels of interlukin (IL)-1β, IL-6, and tumor necrosis factor-α (TNF-α) were determined by enzyme-linked-immunosorbent serologic assay. AMPK and SIRT1 expression levels were quantified through reverse transcription-polymerase chain reaction and Western blotting assay. Results indicated that KR has a certain binding affinity with AMPK. KR could increase the growth of H9c2 inhibited by LPS, reduce apoptosis rate, and reverse the elevated levels of IL-1β, IL-6, and TNF-α. Furthermore, KR could suppress the expression levels of AMPK and SIRT1, and AMPK-specific inhibitor (Compound C) could significantly counteract the activation of KR, indicating that its anti-inflammatory effect is achieved by regulating the AMPK/SIRT1 signaling pathway. [ABSTRACT FROM AUTHOR]

Porcine deltacoronavirus (PDCoV) and porcine sapelovirus (PSV) are two viruses that can cause diarrhoea in pigs and bring great economic loss to the pig industry. In this research, a duplex real-time quantitative polymerase chain reaction (qPCR) assay based on SYBR Green? was developed to simultaneously detect PDCoV and PSV. No specific melting peaks were found in other porcine diarrhoea-associated viruses, indicating that the method developed in this study had good specificity. The detection limits of PDCoV and PSV were 1.0 × 101 copies µl-1 and 1.0 × 102 copies µl-1, respectively. The duplex real-time qPCR assay tested two hundred and three (203) intestinal and faecal samples collected from diarrhoeal and asymptomatic pigs. The positive rates of PDCoV and PSV were 20.2% and 23.2%, respectively. The co-infection rate of PDCoV and PSV was 13.8%. To evaluate the accuracy of the developed method, conventional PCR and singular TaqMan real-time qPCR assays for PDCoV/PSV were also used to detect the samples. The results showed that the duplex real-time qPCR assay was consistent with the singular assays, but its sensitivity was higher than conventional PCR methods. This duplex real-time qPCR assay provides a rapid, sensitive and reliable method in a clinic to simultaneously detect PDCoV and PSV. [ABSTRACT FROM AUTHOR]

Introduction: The integrated county healthcare consortium (ICHC) is becoming an important measure to improve the capacity of primary-level medical services and to achieve grading diagnosis and treatment system in China. However, it is not clear whether health professionals are satisfied with this reform and what are the problems with it. This study aimed to understand the satisfaction of healthcare professionals to the ICHC in Zhejiang Province, China, and analyze the problems and improvement measures of the ICHC. Methods: A cross-sectional study was carried out in the 11 pilot counties (cities and districts) implementing the construction of the ICHC in Zhejiang in November 2019. Healthcare professionals from the leading county-level hospital, three township health centers (THCs) or community health centers (CHCs) in each ICHC were invited to participate in this survey. Results: A total of 3531 healthcare professionals were included, 85.92% of the participants agreed that the integration of the Centers for Disease Control and Prevention (CDC) and other professional public health institutions into the construction of ICHC could actively promote basic public health work. The most severe problem was the lack of financial guarantee fund input (severity score: 2.92 ± 1.76). The most crucial measure to promote the construction of the ICHC was to increase government financial input and improve the security mechanism (importance score: 4.81 ± 0.47). The satisfaction of the healthcare professionals to the ICHC was 89.41%. The satisfaction of healthcare professionals from county-level hospitals was 2.37 (95% CI: 1.760-3.238) times higher than that of healthcare professionals from the township health centers (THCs) or community health centers (CHCs). The satisfaction of health professionals with a college degree or below was 3.215 (95% CI: 1.413-6.786) times higher than that of health professionals with a master's degree or above. Conclusions: Zhejiang Province has taken adequate measures to promote the construction of the ICHC. However, there are still some problems. Appropriate and effective policies should be implemented to enhance policy coordination and promote competition among ICHCs, as well as to strengthen medical service quality management and improve performance appraisal scheme. [ABSTRACT FROM AUTHOR]

Vitis shizishanensis (Vitaceae), a new species from Hubei, China, is described and illustrated. It is morphologically similar to V. flexuosa and V. bryoniifolia, but differs in leaf lobing and pubescence. It can be easily distinguished from the two species based on its glabrous or with very sparse arachnoid tomentum on the abaxial mature leaf surface, and its unlobed to 3-7 lobed leaves. A detailed description, along with photographs for the new species, and a table for morphological comparisons with similar Vitis species, are also provided. [ABSTRACT FROM AUTHOR]

Polymers of intrinsic microporosity (PIMs) have been used as precursors for the fabrication of porous carbon molecular sieve (CMS) membranes. PIM-1, a prototypical PIMmaterial, uses a fused-ring structure to increase chain rigidity between spirobisindane repeat units. These two factors inhibit effective chain packing, thus resulting in high free volume within the membrane. However, a decrease of pore size and porosity was observed after pyrolytic conversion of PIM-1 to CMS membranes, attributed to the destruction of the spirocenter, which results in the "flattening" of the polymer backbone and graphite-like stacking of carbonaceous strands. Here, a spirobifluorene-based polymer of intrinsic microporosity (PIM-SBF) was synthesized and used to fabricate CMS membranes that showed significant increases in p-xylene permeability (approximately four times), with little loss in p-xylene/o-xylene selectivity (13.4 versus 14.7) for equimolar xylene vapor separations when compared to PIM-1-derived CMS membranes. This work suggests that it is feasible to fabricate such highly microporous CMS membranes with performances that exceed current state-of-the-art zeolites at high xylene loadings. [ABSTRACT FROM AUTHOR]

This study reports the recognition of Vitis adenoclada Hand.-Mazz. from southern China. The species was not recognized in the Flora Reipublicae Ropularis Sinicicae and Flora of China treatments. Recent field studies and examination of herbarium collections including the type material suggest that Vitis adenoclada is morphologically similar to V. heyneana, in their densely arachnoid tomentose abaxial leaves, yet it can be easily distinguished from the latter by its red-purple glandular hairs on the young branches (vs. glandular hairs absent in V. heyneana) and inflorescences usually subtended by a tendril at the base (vs. only occasionally with a tendril in V. heyneana). Vitis adenoclada may be a species of hybrid origin, with the highly tomentose Vitis heyneana as one of the parental species, and likely the glandular-hair bearing V. davidii as the other parental species. Vitis adenoclada is recorded from southern China in Guangdong, Guangxi, Guizhou, Hunan and Zhejiang provinces. [ABSTRACT FROM AUTHOR]

The development of vehicle connectivity and autonomy in the ground transportation sector is not only able to enhance traffic safety and driving comfort as well as fuel economy. This study presents a receding-horizon optimization-based control strategy integrated with the preceding vehicle speed prediction model to achieve an eco-driving strategy for connected and automated vehicles (CAVs). In the real traffic scenario where the CAV follows the preceding vehicle on the road, a gated recurrent unit (GRU) network is used to predict the behavior of the preceding vehicle by utilizing the historical inter-vehicle information collected through on-board sensors. Then, a nonlinear model predictive control (NMPC) algorithm is adopted for CAV to minimize the accumulated fuel consumption within the preview horizon. The NMPC approach solves the fuel-optimal speed profile of the CAV, considering a predicted short-term speed preview of the preceding vehicle. With the awareness of the preview speed conditions, the fuel consumption of the CAV is reduced by avoiding unnecessary braking and acceleration, especially during transient traffic conditions. The Pareto front framework is used to examine a trade-off between the vehicle speed prediction accuracy, computational burden, and the fuel consumption of the CAV in the proposed GRU-NMPC design. To analyze the effectiveness of the GRU-NMPC design, adaptive cruise control with constant time headway policy (ACC-CTH) is adopted as a benchmark control design. Comparison results show significant fuel economy improvement of the proposed design and expose possible fuel benefits from vehicle autonomy and sensor fusion technology. [ABSTRACT FROM AUTHOR]

We consider worker skill estimation for the single-coin Dawid-Skene crowdsourcing model. In practice, skill-estimation is challenging because worker assignments are sparse and irregular due to the arbitrary and uncontrolled availability of workers. We formulate skill estimation as a rank-one correlation-matrix completion problem, where the observed components correspond to observed label correlation between workers. We show that the correlation matrix can be successfully recovered and skills are identifiable if and only if the sampling matrix (observed components) does not have a bipartite connected component. We then propose a projected gradient descent scheme and show that skill estimates converge to the desired global optima for such sampling matrices. Our proof is original and the results are surprising in light of the fact that even the weighted rank-one matrix factorization problem is NP-hard in general. Next, we derive sample complexity bounds in terms of spectral properties of the signless Laplacian of the sampling matrix. Our proposed scheme achieves state-of-art performance on a number of real-world datasets. [ABSTRACT FROM AUTHOR]

In the marine environment, marine pollution caused by ship transportation is becoming more serious. The introduction of distributed solar photovoltaic (PV) power generation system in ship power system is an important method to effectively solve marine pollution. Taking the large-scale ocean-going vessels as research objects, this paper studies the application of distributed solar PV power generation in ship power generation system and establishes corresponding models. The results show that solar light intensity and temperature have a non-negligible influence on distributed solar PV power generation system, distributed solar PV arrays have the maximum values, and the maximum power point can be obtained by changing the dynamic load characteristics of the ship. Besides, based on the ship grid-connected system technology, it carries out the studies on the grid-connected and off-grid dual-mode system of ship power generation system and distributed solar PV power generation system, and performs analysis and modelling of the distributed solar PV power generation system. The research in this paper provides operational experience and conditions for the application of distributed solar PV power generation on large ships. [ABSTRACT FROM AUTHOR]

Background: Pigeon crop has the unique ability to produce a nutrient rich substance termed pigeon ‘milk’ (PM), which has functional resemblance with the mammalian milk. Previous researches have demonstrated that a large number of exosomes and exosomal miRNAs exist in mammalian milk, and many of them are associated with immunity, growth and development. However, to date, little is known about the exosomes and exosomal miRNAs in PM. Results: In this study, we isolated the exosomes from PM and used small RNA sequencing to investigate the distribution and expression profiles of exosomal miRNAs. A total of 301 mature miRNAs including 248 conserved and 53 novel miRNAs were identified in five lactation stages i.e. 1d, 5d, 10d, 15d, and 20d. From these, four top 10 conserved miRNAs (cli-miR-21-5p, cli-miR-148a-3p, cli-miR-10a-5p and cli-miR-26a-5p) were co-expressed in all five stages. We speculate that these miRNAs may have important role in the biosynthesis and metabolism of PM. Moreover, similar to the mammalian milk, a significant proportion of immune and growth-related miRNAs were also present and enriched in PM exosomes. Furthermore, we also identified 41 orthologous miRNAs group (giving rise to 81 mature miRNA) commonly shared with PM, human, bovine and porcine breast milk. Additionally, functional enrichment analysis revealed the role of exosomal miRNAs in organ development and in growth-related pathways including the MAPK, Wnt and insulin pathways. Conclusions: To sum-up, this comprehensive analysis will contribute to a better understanding of the underlying functions and regulatory mechanisms of PM in squabs. [ABSTRACT FROM AUTHOR]

This paper presents two observers for estimating the aging condition of selective catalytic reduction (SCR) systems in vehicle applications. SCR systems have been widely recognized as one of the leading engine exhaust gas aftertreatment systems for reducing diesel powertrain tailpipe NOx emissions in ground vehicle applications. While fresh SCRs are quite effective in reducing tailpipe NOx emissions, their NOx reduction capabilities and performances may substantially degrade with in-service aging. To maintain the emission control performance of a SCR system for a diesel engine during the entire vehicle service life, it is thus critical to have an accurate estimation of the SCR system aging condition. In this paper, two Lyapunov-based observers utilizing the measurements of NOx and ammonia concentrations are analytically developed and verified in simulations for estimating the SCR aging condition. The measurement uncertainty is explicitly considered in the observer design process. A sufficient condition for the boundedness of the estimation error is derived. Simulation results under the US06 test cycle demonstrate the effectiveness of the proposed observers. [ABSTRACT FROM AUTHOR]

This paper proposes the complex frequency shifted (CFS) perfectly matched layer (PML) of dispersive media for finite-difference time-domain (FDTD) method combined with weighted Laguerre polynomials (WLP). According to the property of Laguerre basis function, the relative dielectric constant εr(ω) of dispersive media and complex frequency shifted (CFS) PML parameters, auxiliary differential equation (ADE) technique is introduced. Based on the ADE technique, the relationship between field components and auxiliary differential variables is derived in Laguerre domain. Using ADE scheme, the relationship between electric flux density D and electric field E is derived in Laguerre domain. Substituting auxiliary differential variables into CPML absorbing boundary conditions, using auxiliary differential variables, electric flux density D of order q can be expressed directly by magnetic field H in Laguerre domain. Using the same procedure, magnetic field H of order q can be expressed directly by electric field E in Laguerre domain. Inserting H of order q into D, using the relationship between D and E, and using central difference scheme, the formulations for dispersive media are obtained. In order to validate the efficiency of the presented method, two numerical examples are simulated. Numerical results show that, compared with the Berenger PML (BPML) and nearly PML (NPML), the CFS-PML has about more than 24 dB improvement in terms of the maximum relative error and much lower reflection error for the late-time region. [ABSTRACT FROM AUTHOR]

The genus Paracerella Imadaté, 1980 is recorded from China for the first time, with the description of a new species, Paracerella sinensis sp. n. Paracerella sinensis is characterized by four pairs of A-setae on tergite I, the presence of setae Pc and P3a on tergite VII, eight A-setae on tergite VIII, the presence of seta Pc on both sternites VI and VII, and 4/2 setae on sternite VIII, which are different from all other members of the genus. The key to the four species of the genus is updated. In addition, DNA barcodes of four populations are sequenced and their genetic differences are analyzed. [ABSTRACT FROM AUTHOR]

In some batch processes, the variables' trajectories often show obviously functional nature and can be considered as smooth functions rather than just vectors, then the collected three-way data array essentially can be transformed into a two-way function matrix. For this purpose, the approach of functional data analysis (FDA) is introduced to express the variables' functions in this article, which can highlight the subtle differences in the shape of variables' trajectories between normal batches and faulty ones, and can also easily handle the problems of irregular three-way data array, such as unequal batch length, different sampling rates, missing data, etc. Based on the function matrix, a novel monitoring method called multivariate functional kernel principal component analysis (MFKPCA) is proposed for fault detection of batch processes, which directly eigen-decomposes the two-way function matrix in the function space and uses the kernel trick to handle the nonlinear correlations. Different from the traditional PCA method, MFKPCA designs three complementary control charts for batch process monitoring based on three statistics including Hotelling's T 2 , squared prediction error (SPE) and mean squared error (MSE). Finally, some simulations and an industrial semiconductor etch process are used to illustrate the validity of the proposed monitoring method. [ABSTRACT FROM AUTHOR]

We consider a task assignment problem in crowdsourcing, which is aimed at collecting as many reliable labels as possible within a limited budget. A challenge in this scenario is how to cope with the diversity of tasks and the task-dependent reliability of workers; for example, a worker may be good at recognizing the names of sports teams but not be familiar with cosmetics brands. We refer to this practical setting as heterogeneous crowdsourcing. In this letter, we propose a contextual bandit formulation for task assignment in heterogeneous crowdsourcing that is able to deal with the exploration-exploitation trade-off in worker selection. We also theoretically investigate the regret bounds for the proposed method and demonstrate its practical usefulness experimentally. [ABSTRACT FROM AUTHOR]

In this paper, uniaxial anisotropic perfectly matched layer (UPML) absorbing boundary condition (ABC) of dispersive materials is presented for 2-D finite-difference time-domain (FDTD) method with weighted Laguerre polynomials (WLP). Taking advantage of the auxiliary differential equation (ADE) technique, our proposed algorithm avoids not only the complicated formulations but also the convolution integral. Using ADE scheme, the relationship between field components and auxiliary differential variables is derived in Laguerre domain. Substituting auxiliary differential variables into UPML-ABC, the electric field E of order q can be expressed directly by magnetic field H in Laguerre domain. Inserting magnetic field H of order q into electric field, and using central difference scheme, the formulations of uniaxial anisotropic dispersive media PML are obtained. One numerical example of wave propagation in 2-D dispersive materials is simulated. Numerical results validate the efficiency of the presented method. [ABSTRACT FROM AUTHOR]

Based on analyzing the special structure of three-way array and generalizing the concept of additive kernels, this paper proposes the generalized additive kernel principal component analysis (GAKPCA) method for on-line monitoring of batch processes. The proposed method is a special nonlinear principal component analysis (PCA) method which can handle the nonlinear relationships between different monitoring variables and/or time intervals. It inherits the good properties of traditional multiway PCA (MPCA) method for on-line monitoring, and solves some problems that exist in traditional multiway kernel PCA (MKPCA) method. For example, based on the decomposition of batch samples in the feature space, the total squared prediction error ( SPE ) statistic of an entire batch can be divided into K components corresponding to K time intervals respectively, and its score vectors can be directly estimated on-line by the least squares approach without filling the unknown observations. As a special case, when the Gaussian kernel is used as the kernel function at each time interval, the proposed method is connected with the concept of correntropy which can bring robustness to our method. The experimental results on a fed-batch penicillin fermentation process demonstrate the validity of the proposed GAKPCA-based on-line monitoring method. [ABSTRACT FROM AUTHOR]

This paper studies one-parameter formal deformations of Hom-Lie-Yamaguti algebras. The first, second, and third cohomology groups on Hom-Lie-Yamaguti algebras extending ones on Lie-Yamaguti algebras are provided. It is proved that first and second cohomology groups are suitable to the deformation theory involving infinitesimals, equivalent deformations, and rigidity. However, the third cohomology group is not suitable for the obstructions. [ABSTRACT FROM AUTHOR]

We illustrate how a completely new world of gauge force emerges from a conventional condensed matter system in a rigorous way. A characteristic energy scale (Mott gap) separates such an exotic universe from the ordinary one that we condensed matter physicists are more familiar with at higher energies. The governing physical law is no longer about individual electrons but concerns fractionalized particles, i.e., partons, as the new collective modes resulted from strong correlation among the electrons. Novel phenomena in this low-energy universe are clearly distinguished from Landau?s Fermi liquid described by the perturbative quantum many-body theory. [ABSTRACT FROM AUTHOR]

The availability of an accurate and systematic channel simulation technique is critical for the verification of the performance of digital radio transceivers designed for use on wireless channels. Despite the abundant results on channel simulation techniques available in the literature, an accurate technique for simulating Nakagami-m fading signals that have nonuniform phase distributions and any prespecified temporal autocorrelation function is not yet available. Such a technique is reported for the first time in this paper. We develop new cumulative distribution function (cdt) mapping methods to generate complex Nakagami sequences from complex Gaussian sequences, based on the independent transformation of their real and imaginary parts. Additionally, we analyze the relationships between the autocorrelation functions of Rayleigh and Nakagami fading signals to determine the autocorrelation function of Rayleigh input that is required to produce a specified autocorrelation function for the Nakagami output. Then, we implement the mapping algorithm to transform Rayleigh sequences with the so-determined autocorrelation functions into Nakagami sequences with the desired prespecified autocorrelation functions. Simulation results verify that our approaches can lead to the accurate simulation of Nakagami fading signals with prespecified autocorrelation functions and nonuniform phase distributions. [ABSTRACT FROM AUTHOR]

In this paper, we study the asymptotic performance of absolute-threshold-and normalized-threshold-based generalized selection combining (AT-GSC and NT-GSC) schemes over generalized fading channels for high average signal-to-noise ratios (ASNRs). By evaluating the asymptotic moment-generating function of the threshold-based GSC output SNRs, we derive the diversity and combining gains for AT- and NT-GSCs with a large class of modulation formats and versatile fading conditions, including different types of fading channels and nonidentical SNR statistics across diversity branches. Our analytical results reveal that the diversity gains of AT- and NT-GSC are equivalent to that of maximal-ratio combining, and the differences in the combining gains for different threshold values and modulation and diversity formats are derived by using the concept of modulation factors. [ABSTRACT FROM AUTHOR]

In this paper, we study the sum throughput maximization with access proportional fairness (APF) for downlink orthogonal frequency-division multiple access (OFDMA) channels. We propose selective multiuser diversity (SMuD) schemes with normalized signal-to-noise ratio (n-SNR)-based ranking for user selection at each carrier to achieve long-term fairness. We also propose a modified absolute signal-to-noise ratio (a-SNR)-ranking-based SMuD scheme, which provides improved performance over the original a-SNR SMuD scheme. The total transmit power is assigned to the allocated carriers using either equal power allocation (EPA) or water filling. Closed-form throughput and fairness expressions for both the n-SNR and a-SNR SMuD schemes with EPA over Rayleigh channels are derived, which are accurate for even highly correlated frequency channels. Numerical results show that the long-term fairness gives a substantially higher rate than the more stringent short- term fairness. The n-SNR scheme brings perfect access fairness; the sum rate is slightly degraded compared to the a-SNR scheme without fairness, and it is not very sensitive to the imperfect estimation of the average channel signal-to-noise ratio. These results put new insight into the achievable downlink OFDMA performance with proportional fairness and the effects of various system and channel parameters. [ABSTRACT FROM AUTHOR]

Hybrid-selection/equal-gain combining (HS/EGC) is a new diversity format in which a subset of branches with the largest signal-to-noise ratios are selected and combined per EGC rule. It provides a performance close to the hybrid-selection/maximum-ratio combining, and yet with a lower implementation complexity, and thus may be regarded as a promising candidate diversity format for multipath channels or multiple-antenna systems. In this paper, to enable HS/EGC diversity for nonconstant modulus modulation formats, we propose the relevant HS/]EGC receiver structure and decision variable. By deriving the moment-generating function expression for the HS/EGC output signal amplitude and with the help of Parseval's theorem, we develop a general analytical framework to evaluate the error and outage probabilities of predetection HS/EGC for a large class of modulation formats and versatile system and channel parameters. Simulation results verify the validity and accuracy of our analysis. Some insightful findings on the effect of the system and channel parameters are provided. [ABSTRACT FROM AUTHOR]

The effect of spatial correlation on the performance of orthogonal space-time block codes (OSTBCs) over multiple-input-multiple-output (MIMO) Rician fading channels is studied. Asymptotic error-rate formulas for OSTBC with high average signal-to-noise ratios (ASNRs) over arbitrarily correlated Rician MIMO channels are derived in terms of the diversity and coding gains. Our results show that, in correlated fading, the phase vector ϕ of the channel line-of-sight (LOS) components affects the effective Rice K-factor at the OSTBC receiver output and, hence, may result in a coding gain that is significantly higher than that for independent Rician MIMO channels. Furthermore, when the channel covariance matrix is rank deficient and under some additional mild conditions, the error and outage probabilities of OSTBC achieve those in a nonfading additive- white-Gaussian-noise channel. For both cases of full-rank and rank-deficient channel covariance matrices, analytical expressions of optimal and worst case phase vectors ϕ, and exact upper and lower bounds of OSTBC performance are derived. These results provide new insights into the achievable performance of OSTBC over correlated Rician MIMO channels and, if incorporated into future multiple antenna systems design, will bring about signifi- cant performance enhancement. [ABSTRACT FROM AUTHOR]

We study the effect of imperfect channel estimation (ICE) on the error probability performance of M-level quadrature amplitude modulation (M-QAM) with maximal-ratio combining and equal-gain combining diversity formats in Nakagami fading channels. We provide a novel formulation of the bit-error rate (BER) of M-QAM with ICE in terms of the signal constellation-dependent effective signal-to-noise ratios (SNRs) or amplitudes, which allows us to derive the general, accurate, and easy-to-evaluate BER formulas for square and rectangular diversity M-QAM with channel estimation errors. Our result shows that the performance loss caused by ICE may be manifested by the signal decision space distortion and a scaling of the effective SNR. Using our analytical result, we evaluate the performance of M-QAM with pilot-symbol assisted modulation and present some insightful findings. [ABSTRACT FROM AUTHOR]

We study the effect of imperfect channel estimation (ICE) on the error probability performance of M-level quadrature amplitude modulation (M-QAM) with maximal-ratio combining and equal-gain combining diversity formats in Nakagami fading channels. We provide a novel formulation of the bit-error rate (BER) of M-QAM with ICE in terms of the signal constellation-dependent effective signal-to-noise ratios (SNRs) or amplitudes, which allows us to derive the general, accurate, and easy-to-evaluate BER formulas for square and rectangular diversity M-QAM with channel estimation errors. Our result shows that the performance loss caused by ICE may be manifested by the signal decision space distortion and a scaling of the effective SNR. Using our analytical result, we evaluate the performance of M-QAM with pilot-symbol assisted modulation and present some insightful findings. [ABSTRACT FROM AUTHOR]

The effect of spatial correlation on the performance of orthogonal space-time block codes (OSTBCs) over multiple-input-multiple-output (MIMO) Rician fading channels is studied. Asymptotic error-rate formulas for OSTBC with high average signal-to-noise ratios (ASNRs) over arbitrarily correlated Rician MIMO channels are derived in terms of the diversity and coding gains. Our results show that, in correlated fading, the phase vector 4 of the channel line-of-sight (LOS) components affects the effective Rice K-factor at the OSTBC receiver output and, hence, may result in a coding gain that is significantly higher than that for independent Rician MIMO channels. Furthermore, when the channel covariance matrix is rank deficient and under some additional mild conditions, the error and outage probabilities of OSTBC achieve those in a nonfading additive- white-Gaussian-noise channel. For both cases of full-rank and rank-deficient channel covariance matrices, analytical expressions of optimal and worst case phase vectors ø, and exact upper and lower bounds of OSTBC performance are derived. These results provide new insights into the achievable performance of OSTBC over correlated Rician MIMO channels and, if incorporated into future multiple antenna systems design, will bring about significant performance enhancement. [ABSTRACT FROM AUTHOR]

Local and parallel finite element algorithms based on two-grid discretization for Navier-Stokes equations in two dimension are presented. Its basis is a coarse finite element space on the global domain and a fine finite element space on the subdomain. The local algorithm consists of finding a solution for a given nonlinear problem in the coarse finite element space and a solution for a linear problem in the fine finite element space, then droping the coarse solution of the region near the boundary. By overlapping domain decomposition, the parallel algorithms are obtained. This paper analyzes the error of these algorithms and gets some error estimates which are better than those of the standard finite element method. The numerical experiments are given too. By analyzing and comparing these results, it is shown that these algorithms are correct and high efficient. [ABSTRACT FROM AUTHOR]

In this letter, we study the asymptotic performance of hybrid-selection/maximal-ratio combining (HS/MRC) and post-detection HS/equal-gain combining (HS/EGC) over generalized fading channels for large average signal-to-noise ratios (ASNRs). By evaluating the asymptotic moment generating function of the HS/MRC output SNR at high ASNR, we derive the diversity and coding gains for HS/MRC for a large class of modulation formats and versatile fading conditions, including different types of fading channels and nonidentical SNR statistics across diversity branches. Our analytical results reveal that the diversity gains of HS/MRC and HS/EGC are equivalent to that of MRC, and the difference in the coding gains for different modulation formats is manifested in terms of a modulation factor defined in this letter. Some new analytical results about effects of the number of combined branches for HS/MRC and noncoherent combining loss of HS/EGC are also provided. [ABSTRACT FROM AUTHOR]

In this paper, we present a unified mathematical framework to analyze the bit-error rate (BER) performance of general linear coherent multiuser receivers with diversity reception and imperfect channel estimation for doubly selective Rician-fading asynchronous code-division multiple-access channels. BERs of linear receivers with channel state information and data-aided channel estimation are analyzed, and both exact and low-complexity approximate BER evaluation formulas are presented. Furthermore, by using a Markov chain steady-state analysis, a tight BER approximation for receivers with decision-directed channel estimation is proposed. Numerical and simulation results verify the accuracy of the proposed BER evaluation methods. [ABSTRACT FROM AUTHOR]

We study the effect of imperfect channel estimation (ICE) on the performance of M-ary phase shift keying (M-PSK) with maximum ratio combining (MEC) in generalized Rician fading channels. First, we derive the error probability formulas for M-PSK with MRC and ICE in arbitrary Rician fading channels. Furthermore, we derive the effective receiver output signal-to-noise ratio (SNR) statistics and the outage probability, and analytically quantify the average SNR loss of M-PSK caused by ICE, assuming independent diversity branches. Finally, we point out a major approximation in a popular approach used in the literature to evaluate the adverse effect of ICE. [ABSTRACT FROM AUTHOR]

Using a moment-generating function (MGF)-based approach, we study the performance of Mary phase-shift keying (M-PSK) with generalized selection combining (GSC) and equal gain combining (EGC) in fading channels (including Rayleigh, Rician, Nakagamini, and Nakagami-q fading) with independent and identically distributed (i.i.d) branches. Analytical expressions for the error and outage probabilities, the signal-to-noise-ratio (SNR) statistics, and the channel capacity of M-PSK diversity receivers are derived, taking into account the effects of Gaussian weighting errors and all relevant system and channel parameters. Unlike the case of perfect channel-state information (CS!), the outage probability for the ease of imperfect channel estimation (ICE) is not only a function of the normalized SNR with respect to the SNR threshold, but also a function of the operating SNR itself. The SNR toss of the M-PS)( GSC and EGC receivers due to ICE and the relation between the receiver input and output SNRs for ICE are derived. Our results show that, even with ICE, GSC and EGC are effective in improving the output SNR and significantly reduce the error floor and the channel-capacity loss caused by ICE. [ABSTRACT FROM AUTHOR]

In this letter, we give a tight approximation for the bit-error rate (BER) of decision-feedback differential detection (DF-DD). The influence of error propagation is modeled by a Markov chain. A simple state reduction method is proposed to limit computational complexity. Our results show that error propagation strongly depends on the chosen feedback filter. In particular, the popular assumption that error propagation increases BER by a factor of two is not always justified. [ABSTRACT FROM AUTHOR]

Presents a study which formulated the phase distribution in terms of joint moment generating functions (MGF) of the real and imaginary parts of the decision variable at the receiver output using a novel approach. Introduction of the signal model; Formulation of the phase cumulative function in terms of the real and imaginary parts of the decision variable; Derivation of the joint MGF for the decision variables over fading channels.

Presents a proposed general mathematical framework to determine the bit error probability performance for binary coherent and differentially coherent modulation formats with diversity reception in arbitrary Rician fading channels. Discussion of the performance of communication systems using binary coherent and differential phase-shift keyed modulation; Effect of cochannel interference and Gaussian noise on the detection of users in cellular mobile communications.

Focuses on a study which examined the application of a first-order linear state-space model to the asynchronous code-division multiple-access (CDMA) channel. Information on the state-space model of the multiuser CDMA system; Application of the Kalman filter; Simulation results of the study; Conclusion.

Background: To investigate the relationship between lactate dehydrogenase and apolipoprotein A1 levels and the condition and prognosis of patients with severe pneumonia. Methods: Data was collected from 204 patients with severe pneumonia who were hospitalized from January 1, 2019 to December 1, 2021 in Zhaotong First People's Hospital (respiratory intensive care unit (RICLJ)), and divided into survival group (160 patients) and death group (44 patients) according to their hospitalization outcome. The relationship between lactate dehydrogenase and apolipoprotein A1 levels and general information, disease, and treatment needs of patients with severe pneumonia was analyzed, and lactate dehydrogenase, apolipoprotein A1, neutrophil-to-lymphocyte ratio, hematocrit, C-reactive protein, calcitoninogen, D-dimer, Acute Physiology and Chronic Health Status Rating System II, and Pneumonia Severity Index scores were compared between the survival and death groups. The value of these indicators in determining the prognosis of patients was analyzed using subject operating characteristic (ROC) curves. Logistic regression was used to analyze the risk factors for death from severe pneumonia. Results: The age and pneumonia type differed significantly between the two groups (P<0.05). There were no significant differences in gender and total hospitalization days (P>0.05). LDH (Lactate Dehydrogenase) and ApoA1 (Apolipoprotein A1) levels showed significant differences among different age groups with severe pneumonia (P<0.05). LDH and ApoA1 levels did not differ significantly between SCAP (Severe Community-Acquired Pneumonia) and SHAP (hospital-acquired pneumonia) patients (P>0.05). LDH and ApoA1 levels were higher in severe pneumonia patients with acute exacerbation or MODS (multiple organ dysfunction syndrome), compared to those without (P<0.05). LDH and ApoA1 levels varied significantly with PSI (Pneumonia Severity Index) grades or APACHE II (Acute Physiology and Chronic Health Evaluation II) scores, ICU stay duration, and mechanical ventilation duration in severe pneumonia patients (P<0.05). The LDH and ApoA1 levels were significantly higher in the deceased group compared to the survival group (P<0.05). neutrophil-to-lymphocyte ratio (NLR), hematocrit (HCT), C-reactive protein (CRP), calcitoninogen (PCT), D-dimer (DD), PSI scores, and APACHE II scores did not show significant differences between the two groups (P>0.05). LDH and ApoA1, when combined, had a higher predictive value for severe pneumonia mortality (Area Under the Curve, AUC=0.873, P<0.05). Multivariate logistic regression analysis confirmed that LDH >289 U/mL and ApoA1<0.92 mg/mL increased the risk of severe pneumonia mortality (OR=4.275, 0.548, PcO.05). Conclusion: Elevated LDH levels and reduced ApoA1 levels in patients with severe pneumonia are valuable in assessing patients' conditions and prognosis, and can provide assistance in the early assessment of patients' conditions and diagnosis and treatment. [ABSTRACT FROM AUTHOR]

Radial borehole fracturing that combines radial boreholes with hydraulic fracturing is anticipated to improve the output of tight oil and gas reservoirs. This paper aims to investigate fracture propagation and pressure characteristics of radial borehole fracturing in multiple layers. A series of laboratory experiments with artificial rock samples (395 mm × 395 mm × 395 mm) was conducted using a true triaxial fracturing device. Three crucial factors corresponding to the vertical distance of adjacent radial borehole layers (vertical distance), the azimuth and diameter of the radial borehole are examined. Experimental results show that radial borehole fracturing in multiple layers generates diverse fracture geometries. Four types of fractures are identified based on the connectivity between hydraulic fractures and radial boreholes. The vertical distance significantly influences fracture propagation perpendicular to the radial borehole axis. An increase in the vertical distance impedes fracture connection across multiple radial borehole layers and reduces the fracture propagation distance along the radial borehole axis. The azimuth also influences fracture propagation along the radial borehole axis. Increasing the azimuth reduces the guiding ability of radial boreholes, which makes the fracture quickly curve to the maximum horizontal stress direction. The breakdown pressure correlates with diverse fracture geometries observed. When the fractures connect multi-layer radial boreholes, increasing the vertical distance decreases the breakdown pressure. Decreasing the azimuth and increasing the diameter also decrease the breakdown pressure. The extrusion force exists between the adjacent fractures generated in radial boreholes in multiple rows, which plays a crucial role in enhancing the guiding ability of radial boreholes and results in higher breakdown pressure. The research provides valuable theoretical insights for the field application of radial borehole fracturing technology in tight oil and gas reservoirs. [ABSTRACT FROM AUTHOR]

Investigation of Hg isotope ratios of gold-related sulfides and penecontemporaneous mafic dikes from four orogenic gold provinces on the margins of the North China Craton and Yangtze Craton identifies three orogenic gold deposit (OGD) groups from different tectonic regimes. Ore-related sulfides of group 1 OGDs and mafic dikes from the craton margin reworked via oceanic subduction mostly have positive 199Hg values. The group 2 OGDs and mafic dikes from the margin that witnessed complex oceanic and continental subductions have mixed positive to negative 199Hg values. The group 3 OGDs on the margin that experienced continental subduction have dominantly negative 199Hg values. These isotopic differences indicate subduction histories have a first-order control on the distinct sources for the OGDs. It indicates that OGDs were derived from fluids from the mantle lithosphere metasomatized by contrasting subduction components, not from metamorphic fluids as is widely accepted. Group 1 OGDs and dikes were sourced from metasomatized mantle, which inherited the positive 199Hg of both recycled marine sediments and seawater during oceanic subduction, whereas group 3 with negative 199Hg was derived from mantle lithosphere metasomatized by subduction of mainly continental components. This genetic model identifies regions with high-grade metamorphic rocks above metasomatized mantle lithosphere as promising new OGD exploration targets. [ABSTRACT FROM AUTHOR]

Background: Although coronary artery disease and coronary artery spasm (CAS) can lead to acute myocardial infarction, there are clear differences in treatment between coronary heart disease and CAS, and the therapeutic schedule should not be confused. Furthermore, electrocardiogram (ECG) "6+2" phenomenon is recommend as a specific ECG indicator for lesions in the left main coronary artery or multiple vessels. Currently, no reports of this phenomenon in CAS exist. Case Report: A 72-year-old man had history of recurrent chest pain for over 6 years, with episodes lasting about 10 min and resolving with rest. He experienced symptom recurrence and exacerbation due to substance abuse. He was admitted to our Emergency Department for chest pain at rest. His emergency ECG revealed a 6+2 phenomenon, accompanied by troponin levels exceeding 18 times the reference value. Promptly, we conducted coronary angiography, with unexpected normal findings. Following thorough assessment, we postulated the patient could have CAS. Subsequent to medical team intervention, the patient's ECG normalized, leading to his discharge upon condition stabilization. Conclusions: We report a case of CAS in a patient with ECG 6+2 phenomenon, without significant coronary artery stenosis. This differs from transient ST-segment elevation on ECG, a well-recognized hallmark of CAS; however, such a presentation has not been documented before. Additionally, treatment strategies for myocardial ischemic conditions stemming from coronary atherosclerosis diverge from those employed for CAS. Therefore, clinicians should advocate for coronary angiography whenever feasible. This approach serves to elucidate the underlying disease etiology and facilitates the administration of precision-targeted interventions for patients. [ABSTRACT FROM AUTHOR]

The unsymmetrical air flow of the dual slot die in the melt blowing process is simulated. The diameter and transverse displacement of the threadline are obtained numerically. The result shows that the threadline diameter in the unsymmetrical air flow is larger than that in the symmetrical one. This paper helps to point out the research direction for producing finer melt blown fibers. [ABSTRACT FROM AUTHOR]

INTRODUCTION Quitting smoking, the critical path to reach the global targets of reducing tobacco use, can bring major and immediate health benefits to smokers. Exploring factors that help individuals to quit smoking is of great importance. The present study explored influencing factors on smoking cessation, in order to provide comprehensive reference for tobacco control policies. METHODS Ex-smokers and current smokers were recruited online in this crosssectional survey, from 1 October to 31 November 2022, in China. The observational data were collected using a questionnaire to collect information with respect to sociodemographic characteristics of smokers, attitudes towards smoking cessation, details of smoking cessation, and different potential factors related to smoking cessation through open-ended questions. RESULTS A total of 638 smokers from 30 provinces were recruited as eligible respondents, with a mean age of 37.3 ± 11.7 years and a mean smoking history of 15.9 ± 13.7 years. The percentage of males was 92.3%. Of the 638 respondents, only 3.9% had no intention to stop smoking. Among 155 subjects who had quitted smoking successfully, willpower (55.5%) was considered as the most important contributing factor. Among 365 subjects who tried to quit but failed, lack of willpower (28.2%), tobacco dependence (16.2%), influence of surrounding smokers or smoking environments (15.9%), bad moods (9.9%), stress from work or life (7.9%), habits (7.1%), socialization (4.1%), and easy availability of tobacco (2.7%) were considered as the adverse factors leading to failure in quitting smoking. CONCLUSIONS Willpower and support from family members were the vital factors that lead to successful smoking cessation. Future tobacco control policies should also focus on addressing withdrawal symptoms and creating smoke-free environments as well as other factors. [ABSTRACT FROM AUTHOR]

Recent studies indicate that volcanism may be a potentially important factor in the formation of karstic bauxite, but more evidence is needed. Six billion tons of bauxite formed upon paleo-karstic terrain within a short time in the Late Carboniferous in the North China Basin (NCB) and in the Late Permian in the Youjiang Basin (YB) of China. The factors that trigger their apace formation remain unclear. Herein, we proposed that extensive volcanic eruptions have accounted for this large-scale bauxite formation based on the mineralogy, Hg isotopes, and Hg concentration enrichment proxies of the samples of bauxitic sequence in the NCB and YB. NCB bauxite generally has three layers, namely bottom Fe-bearing claystone, intermediate bauxite ore, and top claystone, while bottom Fe-bearing claystone is usually absent in YB bauxite, which directly covers carbonate rocks. The mineral assemblages of NCB and YB bauxite confirm that they were deposited in a superficial alkaline and reducing karstic environment. Strong Hg enrichment peaks with corresponding nearzero Δ199Hg, a signal of excess volcanogenic Hg, were discovered in the upper claystone of NCB bauxitic sequences, which overlaid the Ordovician carbonate substrate. It denotes volcanism occurred immediately subsequent to deposition of terrestrial weathered Al-rich remnants in paleo-karstic depressions during the Late Carboniferous. This volcanism, occurring in the northern margin of the NCB, is considered to have triggered the apace bauxitization in the NCB after its long exposure and weathering. In the YB, the remarkable Hg enrichment and nearzero Δ199Hg were observed in the entire Late Permian bauxitic sequences with Late Permian carbonate as the substrate. It denotes enhanced volcanogenic Hg inputs throughout the whole deposition process of bauxite during the Late Permian. This episode of volcanism associated with the Emeishan large igneous province and contemporaneous arc system resulted in the short term weathering of source materials and the apace bauxitization in YB. Volcanism is suggested to aggravate surface acidic and oxidizing conditions, in which rapid decomposition of source materials occurred to release Al3+ to precipitate diaspore above the physiochemical barrier of underlying carbonate. [ABSTRACT FROM AUTHOR]

Salutaxel (3) is a conjugate of docetaxel (7) and a muramyl dipeptide (MDP) analogue. Docetaxel (7) has been recognized as a highly active chemotherapeutic agent against various cancers. MDP and its analogues are powerful potentiators of the antitumor actions of various tumor-necrotizing agents. This article documents the discovery of compound 3 and presents pharmacological proof of its biological function in tumor-bearing mice. Drug candidate 3 was superior to compound 7 in its ability to prevent tumor growth and metastasis. Compound 3 suppressed myeloid-derived suppressor cell (MDSC) accumulation in the spleens of tumor-bearing mice and decreased various serum inflammatory cytokines levels. Furthermore, compound 3 antagonized the nucleotide-binding oligomerization domain-like receptor 1 (NOD1) signaling pathway both in vitro and in vivo. [ABSTRACT FROM AUTHOR]

Polygonatum polysaccharide (PP) has good myocardial protection. This study aims to find whether PP can relieve inflammation and play a protective role in diabetic cardiomyopathy (DCM). Intraperitoneal injection of streptozotocin was used to induce DCM in rats, which were then separated into four groups: model group, PP-200 group (200 mg/kg PP), PP-400 group (400 mg/kg PP), and Met group (120 mg/kg metformin). Both control (NC) and model groups of rats were administered normal saline. According to the kit instructions mentioned on the kit, the levels of blood glucose, glycosylated hemoglobin, insulin (INS), and myocardial enzymes (creatinine kinase, B-type natriuretic peptide, and cardiac troponin I) were measured after 8 weeks. Cardiac function was detected by echocardiography. Hematoxylin and eosin (HE) and Masson staining were used to observe pathological changes. Myocardial RNA and protein levels of NLR family pyrin domain containing 3 (NLRP3), caspase-1, and Gasdermin D (GSDMD) were quantified through reverse transcription-polymerase chain reaction and Western blotting analysis. The in vivo findings showed that PP could reduce blood glucose, glycosylated hemoglobin, and INS levels, enhance heart functioning, restore histological alterations and myocardial enzymes, and relieve myocardial fibrosis. Furthermore, PP suppressed the expressions of NLRP3, caspase-1, and GSDMD. PP could reduce inflammation in DCM rats by suppressing NLRP3 inflammasome. [ABSTRACT FROM AUTHOR]

In this paper, we try to understand the pseudogap phenomenon observed in the cuprate superconductor through a model study. Specifically, we explore the so-called low-temperature pseudogap state by turning off the superconducting (SC) of diagonal long range order in an ansatz state for the t–J model (Weng 2011 New J. Phys.13 103039). Besides strong non-Gaussian SC fluctuations, the resulting state also exhibits a systematic pseudogap behavior in both spin and charge degrees of freedom, manifested in the uniform spin susceptibility, specific heat, non-Drude resistivity, Nernst effect, as well as the quantum oscillation associated with small Fermi pockets emerging in strong magnetic fields, etc. These anomalous ‘normal state’ properties are found in qualitative consistency with experimental measurements in the cuprates. Such a model study establishes an intrinsic connection between the peculiar pseudogap properties and the non-BCS nature of the SC ground state. A critical comparison with other approaches to the doped Mott insulator is also made. [ABSTRACT FROM AUTHOR]

Plasma-enhanced chemical vapor deposited silicon nitride (SiNx) films are extensively used as passivation material in the solar cell industry. Such SiNx passivation layers are the most sensitive part to gamma-ray irradiation in solar cells. In this work, deep-level transient spectroscopy has been applied to analyse the influence of gamma-ray irradiation on the passivation properties of SiNx layer on silicon. It is shown that the effective carrier lifetime decreases with the irradiation dose. At the same time, the interface state density is significantly increased after irradiation, and its energy distribution is broadened and shifts deeper with respect to the conduction band edge, which makes the interface states becoming more efficient recombination centers for carriers. Besides, C–V characteristics show a progressive negative shift with increasing dose, indicating the generation of effective positive charges in SiNx films. Such positive charges are beneficial for shielding holes from the n-type silicon substrates, i. e. the field-effect passivation. However, based on the reduced carrier lifetime after irradiation, it can be inferred that the irradiation induced interface defects play a dominant role over the trapped positive charges, and therefore lead to the degradation of passivation properties of SiNx on silicon. [ABSTRACT FROM AUTHOR]