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This communication proposes a novel method to design low-profile and miniaturized dual-band microstrip patch antenna for 5G mobile terminals. Magnetic coupling is introduced to excite the parasitic patch that aims to improve the impedance and efficiency bandwidths simultaneously. Magnetic coupling is applied to the first two modes of the half-mode patch, i.e., TM0.5,0 and TM0.5,1 modes, and the effects of the parasitic patch on both modes obey the same physical regulation. As a result, dual band operation with enhanced bandwidths under a low profile is acquired. Slots are etched off for size reduction. The proposed dual-band patch antenna constructed by a pair of back-to-back slotted half-mode patches operating at partial 5G band N78 (3.4~3.6 GHz) and partial N79 (4.8~5.0 GHz) is with a profile of 1 mm (0.012λL) and footprint of 31.35×18 mm2 (0.36×0.21λL2). Measured results show that the -6 dB impedance bandwidths are 9.1% (3.46~3.79 GHz) at lower band and 4.3% (4.97~5.19 GHz) at higher, and the average efficiencies are -1.3 dB (74.1%) and -3.2 dB (47.9%). To the best of the authors’ knowledge, the proposed dual-band patch antenna is with superior performance than most of the reported planar dual-band antennas considering bandwidth and volume.

A differentially fed duplex filtering dielectric resonator antenna (DFDRA) is proposed. This DFDRA combines the functions of the duplexer, the filter and the antenna into one highly integrated multifunctional module. A dual-mode substrate integrated waveguide (SIW) cavity working as the common feeding structure operates at two orthogonal modes at the lower and higher channel and is differentially fed by two pairs of differential input ports. The DRA working as the common radiation element operates at two orthogonal modes at two channels respectively and is excited by two cross slots etched on the top of the SIW cavity. High-isolation between the two channels is realized due to the two pairs of orthogonal operating modes of the DRA and SIW cavity. Measured results show that the balanced DFDRA can operate with differential mode 10dB impedance bandwidth of 2.7% (5.07-5.21 GHz) and 2.6% (5.72-5.87 GHz), the peak realized gains of 4.6-4.9 dBi and 4.8-5.1 dBi for two channels respectively. The isolation between the lower and higher channels is greater than 75dB. Good common mode suppression is realized.

Edge computing pushes computation and storage resources to the network edge which is close to end users, and thus is critical for latency-sensitive applications, e.g., intelligent Vehicular Ad Hoc Networks (VANETs). To enable these services, a set of edge servers need to be deployed to the roadsides. Such deployment should offer low-latency services to end users, while keeping a low deployment or maintenance cost, which is a non-trivial task. In this paper, we study the edge server placement problem in a metropolitan area. This problem is composed of two parts: to determine 1) the locations of the servers and 2) the coverage of each server, with multiple optimization objectives. First, we study the Shanghai Taxi Trace to gain insights into the traffic pattern of taxis, especially how vehicles move between different locations. Second, we build multi-objective optimization models to characterize the trade-off among three critical performance metrics, namely the initial deployment cost, the runtime cost (i.e., number of hand-offs between different servers), and the average delay of tasks. Due to the intractability of these NP-hard problems, we propose a heuristic multi-objective optimization method to decompose the global problem into a set of local problems with tractable scale. Numerical results verify that our heuristic strategy achieves a desirable balance among the three performance metrics, e.g., a 5% compromise of the delay can reduce up to 50% of the hand-offs for small local areas, and 10%+ for the entire global area, compared with the best existing algorithms.

To meet the demands of the new frequency bands and the 4×4 MIMO specification brought by 5G, a triple-band microstrip patch antenna and its four-antenna module are proposed. Based on the half-mode microstrip patch, the first three modes of TM1/2,0, TM1/2,1, and TM3/2,0 that can be independently tuned are engineered to cover the three Chinese 5G bands (N41/N78/N79). The proposed triple-band microstrip patch antenna with the volume of 33.5×32.5×4 mm3 shows the -6-dB frequency bands of 2.47~2.75 GHz, 3.39~3.60 GHz, and 4.69~5.10 GHz, which makes a nice compromise between antenna volume and impedance bandwidths. Four such patches are arranged in a sequentially rotated style to constitute the triple-band four-antenna module, which is with the volume of 71×71×4 mm3. Measured results of the module show high performance. The reflection coefficients of the four elements are almost identical: the bandwidths are 2.50~2.75 GHz, 3.41~3.62 GHz, and 4.68~5.01 GHz; all the isolations are better than -13.3 dB; the average total efficiencies of the four elements are between -1.41~-1.11 dB, -2.45~-2.10 dB, and -1.81~-1.53 dB for N41, N78, and N79, respectively; and all the ECCs are lower than 0.07.

To satisfy the requirement of the sub-6 GHz bands coverage and the 44 MIMO specification for 5G era, a dual-band four-antenna module covering partial 5G bands N78 (3.4~3.6 GHz) and N79 (4.8~4.9 GHz) is proposed for 5G terminal applications. Based on quarter-circle-shaped dual-mode slotted PIFA, the two target bands are covered by the fundamental TM11 mode and a hybrid higher-order mode combined by quasi-TM11 and quasi-TM0,1/2 modes. The four-antenna module is composed by four such PIFA elements that are arranged in a sequentially rotated layout. It presents a circular shape with a diameter of 39.4 mm and is with a low profile of 1.2 mm. The measured results show that the reflection coefficients of the four elements basically cover the target bands; across N78 and N79, the isolations are better than 8.5 dB and 17.6 dB for the neighboring elements, and 19.4 dB and 18.5 dB for the diagonal elements; the average total efficiencies of the four elements are between 38.3%~39.5% for N78 and 39.3%~42.6% for N79; all the ECCs are lower than 0.42.

This article presents a dual-band and dual-polarized microstrip antenna array with broadside beam scanning ability for millimeter-wave applications. Within a compact multilayer structure, wide bandwidth and high port isolation are achieved by using double-layer gridded patches with three groups of metallic via-fences. For beam scanning purpose, a prototype of $2 \times 2$ array is designed, fabricated, and tested. The experimental results agree well with the simulations. For both orthogonal polarizations, the −10 dB bandwidth covers 23.3–31.7 and 42.5–46.5 GHz with average gains of 12 and 13.1 dBi, respectively. A 3 dB beam scanning angle from −51° to 43° at 27 GHz and −28° to 30° at 45 GHz is obtained. The proposed array provides dual-band and wideband properties for dual orthogonal polarizations with competitive beam steering range and compact dimensions, as a feasible solution for fifth-generation (5G) millimeter-wave mobile communications.

Since its first release over a decade ago, the MetaboAnalyst web-based platform has become widely used for comprehensive metabolomics data analysis and interpretation. Here we introduce MetaboAnalyst version 5.0, aiming to narrow the gap from raw data to functional insights for global metabolomics based on high-resolution mass spectrometry (HRMS). Three modules have been developed to help achieve this goal, including: (i) a LC–MS Spectra Processing module which offers an easy-to-use pipeline that can perform automated parameter optimization and resumable analysis to significantly lower the barriers to LC-MS1 spectra processing; (ii) a Functional Analysis module which expands the previous MS Peaks to Pathways module to allow users to intuitively select any peak groups of interest and evaluate their enrichment of potential functions as defined by metabolic pathways and metabolite sets; (iii) a Functional Meta-Analysis module to combine multiple global metabolomics datasets obtained under complementary conditions or from similar studies to arrive at comprehensive functional insights. There are many other new functions including weighted joint-pathway analysis, data-driven network analysis, batch effect correction, merging technical replicates, improved compound name matching, etc. The web interface, graphics and underlying codebase have also been refactored to improve performance and user experience. At the end of an analysis session, users can now easily switch to other compatible modules for a more streamlined data analysis. MetaboAnalyst 5.0 is freely available at https://www.metaboanalyst.ca., Graphical Abstract Graphical AbstractFrom raw data to statistical and functional insights using MetaboAnalyst 5.0.

In overlapping spectrum sharing, due to the complexity of cognitive environment, it is a real challenge for a secondary user (SU) to correctly sense the usage of the spectrum in real time. To tackle this challenge, a social awareness-aided transmit power control policy for SUs is developed. First, a social network composed of a group of third-party sensing nodes that do not share the spectrum with the PU is established, which helps an SU collect the power information of the PU. Then, we design a Dueling Deep Q-Network (DQN) model to achieve efficient dynamic spectrum sharing between the PU and the SU with the power information collected in the social network. Experimental results show that the spectrum sharing success rate is higher and the comprehensive performance is improved with the sensing nodes selected by the social relationship. Moreover, compared with other deep reinforcement learning (DRL) algorithms, the performance of Dueling DQN is more stable on our targeted spectrum sharing problem.

A statistical challenge to analyse hyperspectral data is the multicollinearity between spectral bands. Partial least squares (PLS) has been extensively used as a dimensionality reduction technique through constructing lower dimensional latent variables from the spectral bands that correlate with the response variables. However, it does not take into account the grouping structure of the full spectrum where spectral subsets may exhibit distinct relationships with the response variables. We propose a two-step group penalized PLS regression approach by performing a PLS regression on each group of predictors identified from a clustering approach in the first step. In the second step, a group penalty is imposed on the latent components to select the group with the highest predictive power. Our proposed method demonstrated a superior prediction performance, higher R-squared value and faster computation time over other PLS variations when applied to simulations and a real-world observational data set. Interpretations of the model performance are illustrated using the real-world data example of leaf spectra to indirectly quantify leaf traits. The method is implemented in an R package called “groupPLS”, which is accessible from github.com/jialiwang1211/groupPLS.

Hepatitis B surface antigen (HBsAg) and Hepatitis B surface antibody (anti-HBs) were reported simultaneously among Hepatitis B virus (HBV) infections. HBsAg is a specific indicator of acute or chronic HBV infections, while anti-HBs is a protective antibody reflecting the recovery and immunity of hosts. HBsAg and anti-HBs coexist during seroconversion and then form immune complex, which is rare detected in clinical cases. However, with the promotion of vaccination and the application of various antiviral drugs, along with the rapid development of medical technology, the coexistence of HBsAg and anti-HBs has become more prevalent. Mutations in the viral genomes, immune status and genetic factors of hosts may contribute to the coexistence. Novel HBsAg assays, with higher sensitivity and ability to detect mutations or immune complexes, can also yield HBsAg/anti-HBs coexistence. The discovery of coexistence has shattered the idea of traditional serological patterns and raised questions about the effectiveness of vaccines. Worth noting is that HBsAg/anti-HBs double positivity is strongly associated with progressive liver diseases, especially hepatocellular carcinoma. In conclusion, viral mutations, host factors, and methodology impacts can all lead to the coexistence of HBsAg and anti-HBs. This coexistence is not an indicator of improvement, as an increased risk of adverse clinical outcomes still exists.

In this article, an endfire dual-polarized phased antenna array with small ground clearance is proposed for the fifth-generation (5G) millimeter-wave (mmW) applications with a wide bandwidth. In this array, each antenna element consists of a dipole fed by a microstrip line for horizontal polarization and an H-plane horn using substrate-integrated waveguide (SIW) for vertical polarization. To achieve a wide bandwidth for vertical polarization, two metal vias are added at the aperture of the horn antenna. Then, a four-element antenna array is designed by partially overlapping the aperture of each horn element. A prototype has been fabricated using multilayer printed circuit board (PCB) process. The measured results agree well with the simulated ones. The antenna is with an impedance bandwidth of $\vert \text{S}_{11}\vert dB from 24.4 to 29.5 GHz for both polarizations. The maximum gains of vertical and horizontal polarizations are 9.16 and 9.27 dBi, with the scanning angle from −34° to 33° for both polarizations with gain deterioration less than 3 dB. The proposed antenna is a promising solution for 5G mmW cellphones or antenna-in-package applications.

Ta3N5 is a promising semiconductor for solar-driven photocatalytic or photoelectrochemical (PEC) water splitting. However, the lack of in-depth understanding of its intrinsic defect properties limi...

In this article, the guided-wave modes and leaky-wave characteristic of rectangular metal strips are investigated to realize endfire radiation. By strategically exciting the high-order TE1 leaky-wave mode in the metal strip, a transverse in-phase $E$ -field could be realized to generate an endfire radiation. An effective scheme is validated to manipulate the phase constant and leaky rate by altering the width of the TE1 mode metal strip. Then, to further tailor the phase constant and leaky rate for achieving an enhanced directivity, periodic grooves are etched on both edges of the metal strip to slowdown the phase velocity to a surface-wave mode. To verify this concept, an all-metal planar prototype of corrugated rectangular metal strip (CRMS) was fabricated and measured. Both the full-wave simulation and experimental results show that the CRMS could offer a high endfire gain of 14.2 dBi within a footprint of $3.0\times 0.5\lambda _{0}^{2}$ . Moreover, a broad overlapping bandwidth of 27.7% is realized with $S_{11} dB, gain variation less than 3 dB, and total efficiency better than 90%. The proposed design scheme paves the way for the traveling-wave antenna with simple structure, wide bandwidth, high gain, and good platform accommodation.

miRNet is an easy-to-use, web-based platform designed to help elucidate microRNA (miRNA) functions by integrating users' data with existing knowledge via network-based visual analytics. Since its first release in 2016, miRNet has been accessed by >20 000 researchers worldwide, with ∼100 users on a daily basis. While version 1.0 was focused primarily on miRNA-target gene interactions, it has become clear that in order to obtain a global view of miRNA functions, it is necessary to bring other important players into the context during analysis. Driven by this concept, in miRNet version 2.0, we have (i) added support for transcription factors (TFs) and single nucleotide polymorphisms (SNPs) that affect miRNAs, miRNA-binding sites or target genes, whilst also greatly increased (>5-fold) the underlying knowledgebases of miRNAs, ncRNAs and disease associations; (ii) implemented new functions to allow creation and visual exploration of multipartite networks, with enhanced support for in situ functional analysis and (iii) revamped the web interface, optimized the workflow, and introduced microservices and web application programming interface (API) to sustain high-performance, real-time data analysis. The underlying R package is also released in tandem with version 2.0 to allow more flexible data analysis for R programmers. The miRNet 2.0 website is freely available at https://www.mirnet.ca.

For the first time, zero-ground-clearance dual antenna pair with high isolation and balanced high performance is proposed. A T-shaped monopole intersects with a T-shaped slot that is etched on a large ground edge, constituting the CPW-fed dual antenna pair. By exploiting the odd and even modes of the CPW structure, two orthogonal characteristic modes including the in-phase current and monopole modes can be excited, generating high port isolation. Both modes are unbalanced mode, which means that the ground currents can be fully excited, so the two antennas are with balanced high performance. A sub-6 GHz antenna pair that occupies a footprint of $15\times 7$ mm2 ( $0.18\,\,\lambda \,\times 0.08\,\,\lambda$ ) is analyzed and the simulated results show an isolation of better than −24 dB and an envelope correlation coefficient (ECC) of lower than 0.0016, −6 dB bandwidths of 230 and 240 MHz, and average efficiencies of 57.9% and 57.4%. A four-antenna multiple-input multiple-output (MIMO) array is fabricated and measured to verify the feasibility. The measured isolations and ECCs of the two modes are, respectively, better than −20.0 dB and 0.04, −6 dB bandwidths are 230 MHz/240 MHz and 220 MHz/230 MHz, and average efficiencies are 54.5%/50.2% and 49.9%/48.6%. The proposed dual antenna pair exhibits a great potential for 5G MIMO smartphone application.

For the promising next-generation thin-film solar cells, Cu2SnS3 (CTS) solar cells still suffer from low open circuit voltage (VOC) and so resulting an unsatisfactory power conversion efficiency. Herein, Ag was introduced in solution-processed CTS thin films via adding AgNO3 into precursor solution for photovoltaic devices. Compared with CTS, the VOC deficit for CuxAg2−xSnS3 (CATS) based cells could be effectively reduced for about 10 mV, together with the increased short circuit current density (JSC) and fill factor (FF), a power conversion efficiency of 3.99% was achieved. Such improved performance of CATS cells could be attributed to the improved crystallization, reduced shunting channels and the decreased band-gap of CATS films.

Introduction The aim of this study was to verify less resorption of incompletely developed roots compared with those that were fully developed during the same orthodontic treatment and to test the value of the amount of external apical root resorption for predicting tooth development. Methods A sample of 524 patients aged 10-15 years was selected following the inclusion criteria. For each subject, pretreatment and posttreatment digital panoramic and lateral radiographs were collected, and tooth development was determined from each radiograph. Through calculations, the amount of root resorption was assessed by a created and scientific approach for large-scale application using radiographs with only 8 measurement indexes for each patient. Other basic information and treatment parameters regarded as possible risk factors were also collected from standardized recordings or radiographs. The root length between the groups or in the single group were compared with t tests and correlation analyses. Linear univariate and multivariate regression analyses were used to test identify predictors for root resorption and to develop a prediction model. Results There was a statistically significant difference in the amount of root resorption with tooth development before correction (P Conclusions There is an association between root resorption and tooth development, and tooth development is an important predictor of root resorption. Patients with immature teeth are at a much lower risk of apical root resorption.

With the outbreak of unknown pneumonia in Wuhan, China, in December 2019, a new coronavirus, Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), aroused the attention of the entire world. The current outbreak of infections with SARS-CoV-2 is termed Coronavirus Disease 2019 (COVID-19). The World Health Organization declared COVID-19 in China as a Public Health Emergency of International Concern. Two other coronavirus infections-SARS in 2002-2003 and Middle East Respiratory Syndrome (MERS) in 2012-both caused severe respiratory syndrome in humans. All 3 of these emerging infectious diseases leading to a global spread are caused by β-coronaviruses. Although coronaviruses usually infect the upper or lower respiratory tract, viral shedding in plasma or serum is common. Therefore, there is still a theoretical risk of transmission of coronaviruses through the transfusion of labile blood products. Because more and more asymptomatic infections are being found among COVID-19 cases, considerations of blood safety and coronaviruses have arisen especially in endemic areas. In this review, we detail current evidence and understanding of the transmission of SARS-CoV, MERS-CoV, and SARS-CoV-2 through blood products as of February 10, 2020, and also discuss pathogen inactivation methods on coronaviruses.

Ischemic stroke remains to be a leading cause of death and disability worldwide at present. Cerebral ischemia/reperfusion injury (CIRI) is a critical pathogenesis leading to a poor prognosis for ischemic stroke patients.Recent studies have found that miR155 may be involved in the occurrence of CIRI after stroke, but it’s role and specific mechanism are not completely clear.Therefore, this study investigated the effects of miR155 expression levels on mortality, cerebral infarction volume and neuronal apoptosis in MCAO/R rats by changing the expression level of miR155 in the ischemic penumbra (IP) region of rats. QRT-PCR and Western Blotting were used to detect the expression changes of Rheb, mTOR, 4EBP1 and S6K1 under different miR155 expression levels. The results showed that inhibition of miR155 could reduce the mortality, the volume of cerebral infarction and the number of neuronal apoptosis in MCAO/R rats.The mRNA and protein expressions of Rheb, mTOR, 4EBP1 and S6K1 were increased after inhibition of miR155, and vice versa. It suggested that inhibition the expression of miR155 could alleviate CIRI in the IP by activating Rheb/mTOR signaling at the transcriptional level. At the same time, we found that the phosphorylation level of mTOR signaling pathway were also increased after inhibition of miR155, indicating that autophagy level regulated by mTOR signaling pathway may be involved in the CIRI.

In order to better understand how the brain perceives faces, it is important to know what objective drives learning in the ventral visual stream. To answer this question, we model neural responses to faces in the macaque inferotemporal (IT) cortex with a deep self-supervised generative model, β-VAE, which disentangles sensory data into interpretable latent factors, such as gender or age. Our results demonstrate a strong correspondence between the generative factors discovered by β-VAE and those coded by single IT neurons, beyond that found for the baselines, including the handcrafted state-of-the-art model of face perception, the Active Appearance Model, and deep classifiers. Moreover, β-VAE is able to reconstruct novel face images using signals from just a handful of cells. Together our results imply that optimising the disentangling objective leads to representations that closely resemble those in the IT at the single unit level. This points at disentangling as a plausible learning objective for the visual brain., Little is known about the brain’s computations that enable the recognition of faces. Here, the authors use unsupervised deep learning to show that the brain disentangles faces into semantically meaningful factors, like age or the presence of a smile, at the single neuron level.

This paper proposes a polarization-orthogonal co-frequency dual antenna pair suitable for fifth-generation (5G) multiple-input multiple-output (MIMO) smartphone with metallic bezels. The proposed spatial-reuse dual antenna pair consists of a split on the metallic bezel and a slot on the mainboard ground, where the slot is centered on the split. Two orthogonal degenerate characteristic modes operating at half wavelength including in-phase current and slot modes can be excited on the same antenna structure. An end-shorted microstrip line that crosses the split is used to excite the in-phase current mode, producing $y$ -polarized radiation, while a symmetrical slot-centered Y-shaped feeding network with its shorted ends crossing the slot is adopted to excite the slot mode, producing $x$ -polarized radiation. To the best of authors’ knowledge, this is the first time that a co-frequency dual antenna pair suitable for smartphone with metallic bezels is proposed. A sub-6 GHz dual antenna pair operating at 3.5 GHz that occupies a footprint of $25 \times 7 \times 1.5$ mm3 shows a simulated isolation better than −24.1 dB without any external decoupling measures and an envelope correlation coefficient (ECC) lower than 0.008. A four-antenna MIMO array is fabricated and measured to verify the feasibility. Across the operation band, the measured isolation of the antenna pair is better than −20.1 dB and other isolation levels are all better than −12.7 dB, the ECCs of any two antennas are lower than 0.13, and the total efficiency range of the four antennas is 35.2%~64.7%. The proposed dual antenna pair exhibits a great potential to be applied in future 5G MIMO smartphone.

Background Demographic characteristic surveillance of transfusion-transmitted infections (TTIs) among blood donors is crucial to formulating control strategies and preventing TTIs. This study aimed to investigate the demographic characteristics and social factors associated with TTIs among blood donors from 14 different blood centers or banks in China, covering almost the entire China. Methods Demographic information of 1976 blood donations were obtained from the donor databases of 14 blood centers. The results of the samples were confirmed by the National Center for Clinical Laboratories (NCCL). Results Of the 1976 donations, 928 were confirmed as TTI positive (HBV, 309; HCV, 162; HIV, 116; syphilis, 341), while 1048 tested negative. The differences in demographic distribution of TTI positive and negative donations regarding age, previous donation history, occupation, and education were statistically significant (p

Kesterite Cu2ZnSn(S,Se)4 (CZTSSe) shows great promise in thin film photovoltaic application due to its reasonable band gap, low cost and non-toxic earth-abundant composition. Post-selenization is the generally adopted approach to obtain CZTSSe film with large-grain size. Thoroughly understanding and well controlling the grain growth process during selenization is thus essential for achieving high-performance solar cell devices. Here we demonstrate that the absorber microstructure can be adjusted by altering selenization conditions, especially the heating rate and annealing time. It is found that heating rate determines formation manner of top CZTSSe layer, while annealing time affects both the crystallization degree of bottom CZTSSe layer and the selenization of Mo contact layer. Properly adjusting the annealing time at an optimized heating rate is proven to successfully eliminate the fine-grain layer and obtain high quality CZTSSe thin films with large-size grains. Based on the observations, growth mechanisms for the microstructure development during selenization of solution processed Cu2ZnSnS4 films are suggested. Finally, CZTSSe device efficiency of 9.24% is achieved at an optimal selenization condition.

Background: Dyslipidemia contributes to the development and progression of cardiovascular disease. However, the potential association between non-high-density lipoprotein-cholesterol-to-high-density lipoprotein-cholesterol (nonHDLc/HDLc) ratio and mortality in septic patients is unclear.Methods: This was a retrospective cohort study of patients with sepsis in the eICU Collaborative Research Database (eICU-CRD) from 208 distinct ICUs across the United States between 2014 and 2015. All-cause mortality within 28-days after ICU admission. A multivariable logistic regression model was used to estimate the risk of death.Result: Of the 724 patients with a median age of 68 years, 43 (5.94%) died within 28 days after ICU admission. The association between the nonHDLc/HDLc ratio and the risk of all cause mortality was J shaped, and a high level was associated with increased risk of all cause mortality. The mortality rate increased when the nonHDLc/HDLc ratio higher than the turning point (≥3.41) with an adjusted odds ratio (OR) of 1.34 (95% CI: 1.07–1.67, P=0.010) for every 1 increment of nonHDLc/HDLc ratio. With the per-SD increase in the nonHDLc/HDLc ratio, the OR of mortality was 1.79 (95% CI: 1.15–2.80, P=0.010) when the nonHDLc/HDLc ratio was ≥3.41. The trend of sensitivity analysis was consistent with the main analysis.Conclusion: For patients with sepsis, the association between the nonHDLc/HDLc ratio and the 28-day mortality risk was J shaped. A higher level of nonHDLc/HDLc ratio was associated with an increased risk of 28-day mortality. These findings need to be confirmed in other studies.

Aiming at the unsatisfactory efficiency of concept word extraction from unstructured text for domain ontology construction, this work first uses a combined statistic to judge the correctness of the concept word boundary determined by the word segmentation, and corrects the wrong segmentation position, thereby strengthening the structural integrity of the segmented candidate concept words. On this basis, the improved methods and various resource libraries are used to adjust the weight of concept words, and the main purpose is to strengthen the correlation between the weight and its domain attributes of concept words. We conducted experiments and comparisons on English-Chinese bilingual corpus, and found that the method of strengthening the structural integrity of concept words and the method of dynamically adjusting the weight of concept words proposed in this paper both brought a certain improvement in the efficiency of concept word extraction.

In analog circuit, the component parameters have tolerances and the fault component parameters present a wide distribution, which brings obstacle to classification diagnosis. To tackle this problem, this article proposes a soft fault diagnosis method combining the improved barnacles mating optimizer(BMO) algorithm with the support vector machine (SVM) classifier, which can achieve the minimum redundancy and maximum relevance for feature dimension reduction with fuzzy mutual information. To be concrete, first, the improved barnacles mating optimizer algorithm is used to optimize the parameters for learning and classification. We adopt six test functions that are on three data sets from the University of California, Irvine (UCI) machine learning repository to test the performance of SVM classifier with five different optimization algorithms. The results show that the SVM classifier combined with the improved barnacles mating optimizer algorithm is characterized with high accuracy in classification. Second, fuzzy mutual information, enhanced minimum redundancy, and maximum relevance principle are applied to reduce the dimension of the feature vector. Finally, a circuit experiment is carried out to verify that the proposed method can achieve fault classification effectively when the fault parameters are both fixed and distributed. The accuracy of the proposed fault diagnosis method is 92.9% when the fault parameters are distributed, which is 1.8% higher than other classifiers on average. When the fault parameters are fixed, the accuracy rate is 99.07%, which is 0.7% higher than other classifiers on average.

Understanding how the brain represents the identity of complex objects is a central challenge of visual neuroscience. The principles governing object processing have been extensively studied in the macaque face patch system, a sub-network of inferotemporal (IT) cortex specialized for face processing. A previous study reported that single face patch neurons encode axes of a generative model called the “active appearance” model, which transforms 50D feature vectors separately representing facial shape and facial texture into facial images. However, a systematic investigation comparing this model to other computational models, especially convolutional neural network models that have shown success in explaining neural responses in the ventral visual stream, has been lacking. Here, we recorded responses of cells in the most anterior face patch anterior medial (AM) to a large set of real face images and compared a large number of models for explaining neural responses. We found that the active appearance model better explained responses than any other model except CORnet-Z, a feedforward deep neural network trained on general object classification to classify non-face images, whose performance it tied on some face image sets and exceeded on others. Surprisingly, deep neural networks trained specifically on facial identification did not explain neural responses well. A major reason is that units in the network, unlike neurons, are less modulated by face-related factors unrelated to facial identification, such as illumination.

Manufacturers are disseminating false or ambiguous information regarding new energy vehicles (NEVs), which has led to skepticism from consumers about the quality of NEVs. In this research, we simultaneously considered the relationship among manufacturers, consumers, and governments from the perspective of stakeholders, and then we analyzed the tripartite coordinated regulation. In view of the serious information asymmetry of NEVs, we innovatively developed the Bayesian dynamic game model. By solving refined Bayesian equilibrium strategies, this study explores the effects of key influencing factors on strategic choices. On the basis of the conclusion, relevant countermeasures and suggestions are put forward to engender effective regulation by governments.

In this study, we investigate the seroprevalence of SARS-CoV-2 antibodies among blood donors in the cities of Wuhan, Shenzhen, and Shijiazhuang in China. From January to April 2020, 38,144 healthy blood donors in the three cities were tested for total antibody against SARS-CoV-2 followed by pseudotype SARS-CoV-2 neutralization tests, IgG, and IgM antibody testing. Finally, a total of 398 donors were confirmed positive. The age- and sex-standardized SARS-CoV-2 seroprevalence among 18–60 year-old adults (18–65 year-old in Shenzhen) was 2.66% (95% CI: 2.24%–3.07%) in Wuhan, 0.033% (95% CI: 0.0029%–0.267%) in Shenzhen, and 0.0028% (95% CI: 0.0001%–0.158%) in Shijiazhuang, respectively. Female sex and older-age were identified to be independent risk factors for SARS-CoV-2 seropositivity among blood donors in Wuhan. As most of the population of China remained uninfected during the early wave of the COVID-19 pandemic, effective public health measures are still certainly required to block viral spread before a vaccine is widely available., Here, the authors determine seroprevalence of antibodies to SARS-CoV-2 in healthy blood donors in the cities of Wuhan, Shenzhen, and Shijiazhuang in China between January and April 2020. The age- and sex-standardized SARS-CoV-2 seroprevalence among 18–60 year-old adults is, with 2.66%, the highest in Wuhan.

Background: Dyslipidemia contributes to the development and progression of cardiovascular disease. The objective of this study was to investigate the association between the non-high-density lipoprotein-cholesterol-to-high-density lipoprotein-cholesterol (non-HDL-c/HDL-c) ratio and mortality for patients with sepsis.Methods: Using data from the eICU Collaborative Research Database (eICU-CRD) with high granularity data for over 200,000 admissions to ICUs monitored by eICU Programs across the United States. We identified 1680 patients with sepsis. All-cause mortality within 30-days after the date of visit to the ICU. We estimated the risk of mortality using multivariable logistic-regression model.Result: There were 115 deaths (6.85%). The probability of mortality decreased when the nonHDLc/HDLc ratio lower than the turning point ( P=0.011) for every 1 increment of nonHDLc/HDLc ratio. With the per-SD increase in the nonHDLc/HDLc ratio, the OR for mortality was 0.36 (95% CI: 0.16–0.79, P=0.011) when nonHDLc/HDLc ratio was PConclusion: Higher nonHDLc/HDLc ratio, even at a low level, was associated with a higher risk of 30-day mortality for patients with sepsis. The probability of mortality rose rapidly when the nonHDLc/HDLc ratio higher than the turning point (may at 3.58).

Background: Clinical evidence shows that mortality in relation to the potassium ranges was U-shaped in patients with hypertension, heart failure and cardiovascular disease. However, evidence is lacking for patients with cardiac arrhythmias in the emergency department. Present study aimed to clear the relationship between serum potassium level and mortality for patients with cardiac arrhythmias in the emergency department.Methods: Using data from a retrospective cohort study, we identified 7532 visits involving 3882 patients with cardiac arrhythmias referred for any reason to the emergency department (ED) between January 1, 2010, and December 31, 2015. All-cause mortality within 30-days after the date of visit to the ED. We estimated the risk of mortality using multivariable logistic-regression model.Results: There were 448 deaths (5.9%). The probability of mortality rose rapidly when potassium higher than the turning point (potassium ≥ 4.3 mmol/L) with a adjusted OR of 1.13 (95% CI:1.09, 1.16) for every 0.1 mmol/L increment of potassium. Moreover, the probability of mortality decreased when potassium lower than the turning point (potassium < 4.3 mmol/L) with a adjusted OR of 0.95 (95% CI:0.91, 0.98). Conclusions: Higher serum potassium, even at a low level, was associated with a higher risk of 30-day mortality for patients with cardiac arrhythmias in the emergency department. The probability of mortality rose rapidly when potassium higher than the turning point (may at 4.3 mmol/L).

Based on the discussion of the perception layer, network layer and application layer of the Internet of Things (IOT), this paper constructs a platform for cultivating senior technical talents of the Internet of things, which takes the application layer as the core, radiates the perception layer and network layer, provides the comprehensive and high-quality characteristics of senior technical talents, and discusses the senior technical talents with advanced engineering technology background, and create senior technical personnel with high starting point, strong application ability and strong engineering adaptability.

Vision-based sensors such as LiDAR (Light Detection and Ranging) are adopted in the SLAM (Simultaneous Localization and Mapping) system. In the 16-beam LiDAR aided SLAM system, due to the difficulty of object detection by sparse laser data, neither the grid-based nor feature point-based solution can avoid the interference of moving objects. In an urban environment, the pole-like objects are common, invariant and have distinguishing characteristics. Therefore, it is suitable to bring more robust and reliable positioning results as auxiliary information in the process of vehicle positioning and navigation. In this work, we proposed a scheme of a SLAM system using a GNSS (Global Navigation Satellite System), IMU (Inertial Measurement Unit) and LiDAR sensor using the position of pole-like objects as the features for SLAM. The scheme combines a traditional preprocessing method and a small scale artificial neural network to extract the pole-like objects in environment. Firstly, the threshold-based method is used to extract the pole-like object candidates from the point cloud, and then, the neural network is applied for training and inference to obtain pole-like objects. The result shows that the accuracy and recall rate are sufficient to provide stable observation for the following SLAM process. After extracting the poles from the LiDAR point cloud, their coordinates are added to the feature map, and the nonlinear optimization of the front end is carried out by utilizing the distance constraints corresponding to the pole coordinates, then, the heading angle and horizontal plane translation are estimated. The ground feature points are used to enhance the elevation, pitch and roll angle accuracy. The performance of the proposed navigation system is evaluated through field experiments by checking the position drift and attitude errors during multiple two-min mimic GNSS outages without additional IMU motion constrain such as NHC (Nonholonomic Constrain). The experimental results show that the performance of the proposed scheme is superior to that of the conventional feature point grid-based SLAM with the same back end, especially in congested crossroads where slow-moving vehicles are surrounded and pole-like objects are rich in the environment. The mean plane position error during two-min GNSS outages was reduced by 38.5%, and the root mean square error was reduced by 35.3%. Therefore, the proposed pole-like feature-based GNSS/IMU/LiDAR SLAM system can fuse condensed information from those sensors effectively to mitigate positioning and orientation errors, even in a short-time GNSS denied environment.

The formulation of proper financial penalties plays an important role in regulating Chinese traditional energy enterprises’ illegal pollution. Through the construction of a mixed-strategy game model and an evolutionary game model for regulatory agencies and traditional energy enterprises, the article studies how financial penalties impact players’ strategies and evolutionary processes to optimize financial penalties. It found that excessive financial penalties could reduce enforcement, but insufficient financial penalties would cause more pollution discharge violations. The article concludes that Chinese environmental laws should focus more on setting reasonable penalties based on the profit from activities that generate illegal pollution rather than on the environmental damage to improve regulatory effectiveness.

Taiwanese Mahjong (Tai-Mah) is a popular multiplayer tile-based game in Taiwan that presents imperfect information. Predicting the behavior of opponents is an essential aspect of Tai-Mah, and superior ability in doing so distinguishes master players from ordinary players. This paper presents a rule- based Tai-Mah AI using an opponent behavior prediction agent to optimize the AI. The agent can predict the probability of the Mahjong tiles that an opponent needs based on heuristic Tai-Mah principles, which is then verified by game records. It was observed that the AI exhibited better performance than the average human player even before the use of the prediction agent, with the winning percentage being 25.455% over 21.638%. After the implementation of the prediction agent, the performance of AI significantly improved compared to the previous version, with the winning percentage increasing to 28.830% over 17.953%. The proposed AI is easy to adjust, can reduce players’ waiting time (since a Mahjong game requires four players), and improve players’ gaming experience. Therefore, it is suitable for commercial use, and our AI is currently being used in the industry.

China now is the largest natural gas importer in the world, with the dependency on foreign countries has reached to 45.3%.On the other hand, China has a huge amount of natural gas resources in the South China Sea to be developed, but most of them are CO2-rich gas which contains 15%~80% CO2 located in the deep sea. How to develop these valuable offshore gas resources economically, efficiently, sustainably and environmental friendly, without causing greenhouse gas emission, has always been one of the biggest challenges in the offshore petroleum industry. Power-to-Hydrogen (PTH) from offshore renewables and CO2 methanation are expected to provide a new technical solution for the utilization of offshore CO2-rich gas. This method can improve the composition of CH4 to meet the requirements of economic pipeline transportation, and even the requirements of liquefaction to LNG. However, this technology is still under development. Regardless of the technology itself, the bottleneck exists in the balance between the costs of hydrogen and natural gas production and the economy condition for the whole life cycle of gas field development. But this technology still has the potential to provide a new solution for the development of CO2-rich natural gas resources. It is preliminary estimated that when the costs of offshore power are less than ¥0.3 / kWh, the project can be commercialized.

Background So far, the prevalence of human T-lymphotropic virus (HTLV) type 1 and 2 in some highly populated countries such as China is still unknown. In this study, a multi-center nationwide serological survey was designed and performed, to reveal the seroprevalence of HTLV infection among Chinese blood donors. Results Among 8,411,469 blood donors from 155 blood establishments, 435 were finally confirmed as HTLV carriers. The prevalence of HTLV infection in China varied in different provinces: Fujian had the highest prevalence of 36.240/100,000 (95% CI 31.990–41.050) and eleven provinces did not find HTLV-seropositive donors in the three years. no HTLV-2 infection was found. The overall prevalence of HTLV-1 in China decreased from 2016 to 2018. Female was identified as an independent risk factor of HTLV infection in China. Besides, seroconversion was observed in two of seven seroindeterminate donors 85 and 250 days after their last donation, respectively. Conclusions The seroprevalence of HTLV infection in most areas of China among blood donors is quite low, but it varies significantly in different geographic areas. Screening anti-HTLV-1/2 antibody and follow-up of serointederminate donors are essential to ensure blood safety especially in areas where we have found HTLV infected donors.

Background. Enzyme-linked immunosorbent assay (ELISA) is the only serological method approved for blood screening in China. Automated chemiluminescence immunoassay (CLIA) and electrochemiluminescence immunoassay (ECLIA) had been used in clinical laboratories but not applied to screen HIV among blood donors. This study aimed to evaluate the performance of ELISA, CLIA, and ECLIA, focusing on the feasibility of CLIA/ECLIA for blood screening. Method. 1029 blood donations from 14 blood centers screened by ELISA were enrolled in the study. All plasma samples were tested by eight ELISA assays in 16 blood centers, followed by the detection of CLIA and ECLIA methods in the National Center for Clinical Laboratories (NCCL), further confirmed by nucleic acid testing (NAT) and Western blot (WB). Results. Of 1029 samples, 136 were confirmed as HIV positive. CLIA and ECLIA assay had similar sensitivities with ELISAs but showed higher specificity (CLIA: 99.1%, 885/893; ECLIA: 99.0%, 884/893), concordance rate (CLIA: 99.2%, 1021/1029; ECLIA: 99.1%, 1020/1029), and positive predictive value (PPV) (CLIA: 94.4%, 136/144; ECLIA: 93.8%, 136/145) than most of ELISA kits (>5 ELISAs) (P<0.05). Kappa values of CLIA (0.967) and ECLIA (0.963) were the highest among all the serologic assays. Among 451 samples with initial ELISA reactivity, 315 were negatives, of which 307 (97.5%) and 306 (97.1%) were detected as nonreactive by CLIA (8 nonspecific reactions) and ECLIA (9 nonspecific reactions), respectively. Conclusion. Compared with ELISA, CLIA and ECLIA are more specific and accurate in detecting HIV antibody/antigen and can keep more nonspecifically reactive donors detected by ELISA. CLIA and ECLIA can be used for the improvement of serological blood screening strategy to avoid the unnecessary loss of blood donors.

Microplastics (MPs) are ubiquitous contaminants in the environment and can be transferred along the food chain, thus causing adverse effects in organisms, even human beings. Therefore, it is of practical importance to identify the environmental risks of MPs, which could lead to a significant impact on public health. In addition to the healthy population, there are large numbers of patients with chronic diseases around the world whose responses to MPs are understudied, representing a significant knowledge gap within the health risk assessment of MPs. In this study, the response sensitivity to MPs of mice with acute colitis was compared with that of healthy mice. The mice were fed water containing polystyrene microplastics (PS MP) at a concentration of 500 μg/L for 28 days. The results showed that PS MP exposure induced inflammatory effects and exerted great disturbance on liver metabolites. Moreover, exposure to PS MP exaggerated dextran sodium sulfate (DSS)-induced acute colitis, as well as lipid disorders, as verified by typical inflammatory factor expression and triglyceride accumulation. The increased intestinal permeability of mice with acute colitis caused by exposure to PS MP may be responsible for the upregulated adverse effects. The results of this study suggest that populations with chronic diseases might be more sensitive to environmental contamination, which should be considered during health risk assessments.

Background Severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) RNA could be detected in the blood of infected cases. From February 9, all blood establishments in Hubei province, China, implemented nucleic acid testing (NAT) for SARS‐CoV‐2 RNA among blood donors to ensure blood safety. Study Design and Methods Nucleic acid test screening individually (ID) or by minipool (MP) testing was performed according to the manufacturerʼs instructions. Inactivated culture supernatant of SARS‐CoV‐2–infected Vero cells was quantified by droplet digital polymerase chain reaction (ddPCR) and series diluted with negative plasma to evaluate the assayʼs performance. Results The limit of detection of the kit for MP testing was 62.94 and 33.14 copies/mL for N and ORF1ab region, respectively. ID testing could achieve 3.87 and 4.85 copies/mL for two regions using 1600 μL of plasma. Coefficients of variations of two different concentrations of reference samples were all less than 5% in MP testing. As of April 30, 2020, a total of 98,342 blood donations including 87,095 whole blood donations and 11,247 platelet donations were tested by ID or MP testing, and no RNAemia was found. In addition, Hubei province suffered precipitously decreased blood supply, especially in February: 86% reduction compared with the same period of 2019. Conclusion Nucleic acid test screening of SARS‐CoV‐2 on blood donations is suitable in blood establishments using the commercial real‐time PCR detection kit based on available instruments. The negative result indicated that SARS‐CoV‐2 appears to be no direct threat to blood safety but raises some serious issues for general blood supply.

In this work, we propose and demonstrate the concept of remote reflections, which help to multiply the photon propagations for increasing the light extraction efficiency (LEE) for both transverse magnetic (TM)- and transverse electric (TE)-polarized light. The remote reflection is enabled by using a remote-metal-reflector-based air cavity extractor. According to our study, the remote reflections can significantly avoid the optical absorption when compared with the conventional inclined-sidewall-shaped deep-ultraviolet light-emitting diodes with the metal Al reflector on the inclined sidewalls. As a result, the optical power for our proposed devices has been significantly enhanced by 55% experimentally. Numerical simulations further reveal that the remote metal reflector not only favors more total internal refection on the inclined sidewalls but also supports additional light escaped channels for enhancing the LEE.

SummaryUnderstanding how the brain represents the identity of complex objects is a central challenge of visual neuroscience. The principles governing object processing have been extensively studied in the macaque face patch system, a sub-network of inferotemporal (IT) cortex specialized for face processing. A previous study reported that single face patch neurons encode axes of a generative model called the “active appearance” model, which transforms 50-d feature vectors separately representing facial shape and facial texture into facial images. However, a systematic investigation comparing this model to other computational models, especially convolutional neural network models that have shown success in explaining neural responses in the ventral visual stream, has been lacking. Here, we recorded responses of cells in the most anterior face patch AM to a large set of real face images and compared a large number of models for explaining neural responses. We found that the active appearance model better explained responses than any other model except CORnet-Z, a feedforward deep neural network trained on general object classification to classify non-face images, whose performance it tied on some face image sets and exceeded on others. Surprisingly, deep neural networks trained specifically on facial identification did not explain neural responses well. A major reason is that units in the network, unlike neurons, are less modulated by face-related factors unrelated to facial identification such as illumination.

Hepatitis B virus (HBV) infection is a major threat to global public health, which can result in many acute and chronic liver diseases. HBV, a member of the family Hepadnaviridae, is a small enveloped DNA virus containing a circular genome of 3.2 kb. Located upstream of the S-open-reading frame of the HBV genome is the pre-S region, which is vital to the viral life cycle. The pre-S region has high variability and many mutations in the pre-S region are associated with several liver diseases, such as fulminant hepatitis (FH), liver cirrhosis (LC), and hepatocellular carcinoma (HCC). In addition, the pre-S region has been applied in the development of several pre-S-based materials and systems to prevent or treat HBV infection. In conclusion, the pre-S region plays an essential role in the occurrence, diagnosis, and treatment of HBV-related liver diseases, which may provide a novel perspective for the study of HBV infection and relevant diseases.

Serological tests have been widely used for detecting human T-cell lymphotropic virus type 1/2 (HTLV-1/2) antibodies in the endemic areas, but their performance in low-risk populations is rarely reported. The aim of this study was to evaluate the performance of four HTLV-1/2 screening assays and to discuss a strategy for diagnosis of HTLV-1/2 infection in a non-endemic area. At the present study, 1546 specimens repeatedly reactive (RR) by one screening ELISA were collected from blood centers/banks from January 2016 to April 2019. Avioq-ELISA, Murex-ELISA, Roche-ECLIA and Fujirebio-CLIA were independently performed on each plasma sample and compared to WB and LIA confirmatory tests. Positive or indeterminate specimens with blood available were quantified by qPCR. The results showed that 48 samples were finally confirmed as HTLV-1 positive, 13 were HTLV positive, 151 were indeterminate, and 387 were negative. All the WB-positive samples were also LIA-positive. Roche-ECLIA showed the highest sensitivity that was able to detect 91.8% positives and combined with the Murex-ELISA would significantly increase the positive detection rate (98.4%). In addition, LIA yield more indeterminate and HTLV-untyped results than WB (152 vs. 27), but was able to resolve infection status of some individuals with an indeterminate WB. Besides, 3 WB indeterminate and 1 LIA-untyped samples were confirmed as HTLV-1 positive by qPCR. Based on these findings, we put forward a proper test strategy for HTLV-1/2 diagnosis in low-prevalence areas. If possible, the Roche-ECLIA with the highest sensitivity is suggested as a second screening assay in primary labs. If not, all RR specimens are recommended to be firstly retested by Roche-ECLIA and Murex-ELISA in the reference lab. Secondly, samples reactive to any one of the two tests were quantified by qPCR, and then the NAT-negatives were furtherly submitted to LIA for confirmation. Thereby, the cost can be reduced and the diagnostic accuracy would be improved.

To analyze the risk and reason of false-negative HBV DNA results of NAT reagents among blood donations of China and discuss the necessity of two amplification targets for HBV DNA tests among donations. In this study, samples that showed discordant results on two commercially available assay platforms were further detected by established in-house methods based on conserved regions of the HBV genome. The HBV concentration of these samples was determined using two commercially available reagents. The samples with high titers of HBV were detected by an in-house method. The samples showing high Ct differences between two regions in the in-house method were further sequenced and aligned with primers and probes. The results showed that the established method has a good detection performance. The mismatch between reverse primers and sample sequences led to decreased detection capacity of S and C regions by the in-house method, but it could be compensated by another region. Among the false-negative samples detected by commercial reagents, most were because of low titers; however, there were 7 samples with HBV DNA concentrations much higher than the LOD of the commercial reagents, which may be due to mismatch of the primer or probe. This study highlights the potential risk of HBV false-negative detection by commercial NAT reagents. The dual-target assay may be helpful for HBV screening and reduce the risk of false-negative detection.

Through utilizing user mobility and short-range device-to-device communication techniques, mobile opportunistic networks (MONs) enable end-to-end message delivery without the dependence on reliable network infrastructures. Examples of these networks include mobile social networks and vehicular networks. Multicast in MONs is used to disseminate information to a group of mobile nodes, which have attracted considerable attention due to high resource utilization. In this paper, we focus on reducing the overhead of multicast in MONs without compromising the delivery performance, through utilizing static social features of nodes and time-varying social behaviors. We first conduct a trace data analysis using the information entropy theory to identify the most important and representative social features in a popular trace, the Infocom06 trace. Based on these static social features, we propose a Social Profile-based Multicast (SPM) routing scheme, that supports efficient multicast message dissemination with a small maintenance overhead, i.e., little cost on maintaining the historical records. Furthermore, by exploring the time-varying social behaviors during daytime and nighttime, we verify that a small number of forwardings during that daytime is sufficient to achieve a desirable delivery ratio. We thus propose an improved overhead-reducing scheme Social Profile-based Multicast-Overhead Reducing (SPMOR) that restricts the number of forwardings during the daytime. The extensive trace-driven simulations show that SPM achieves desirable delivery performance with small maintenance and transmission cost, and SPMOR can further reduce the transmission overhead under diurnal user behaviors. At last, we conduct a similar study on a campus-based MON trace, SocialBlueConn. We find that the main conclusions and performance results on SocialBlueConn are consistent with the Infocom06 trace, which verifies our methodology is scalable.

Summary Emerging and reemerging infectious diseases are global public concerns. With the outbreak of unknown pneumonia in Wuhan, China in December 2019, a new coronavirus, SARS‐CoV‐2 has been attracting tremendous attention. Rapid and accurate laboratory testing of SARS‐CoV‐2 is essential for early discovery, early reporting, early quarantine, early treatment, and cutting off epidemic transmission. The genome structure, transmission, and pathogenesis of SARS‐CoV‐2 are basically similar to SARS‐CoV and MERS‐CoV, the other two beta‐CoVs of medical importance. During the SARS‐CoV and MERS‐CoV epidemics, a variety of molecular and serological diagnostic assays were established and should be referred to for SARS‐CoV‐2. In this review, by summarizing the articles and guidelines about specimen collection, nucleic acid tests (NAT) and serological tests for SARS‐CoV, MERS‐CoV, and SARS‐CoV‐2, several suggestions are put forward to improve the laboratory testing of SARS‐CoV‐2. In summary, for NAT: collecting stool and blood samples at later periods of illness to improve the positive rate if lower respiratory tract specimens are unavailable; increasing template volume to raise the sensitivity of detection; putting samples in reagents containing guanidine salt to inactivate virus as well as protect RNA; setting proper positive, negative and inhibition controls to ensure high‐quality results; simultaneously amplifying human RNase P gene to avoid false‐negative results. For antibody test, diverse assays targeting different antigens, and collecting paired samples are needed.

Because of high rates of 2019 novel coronavirus disease in Wuhan, China, Wuhan Blood Center began screening for severe acute respiratory syndrome coronavirus 2 RNA on January 25, 2020. We screened donations in real-time and retrospectively and found plasma samples positive for viral RNA from 4 asymptomatic donors.

Fibroblast-like synoviocytes (FLSs), with their tumor-like proliferation, play an important role in rheumatoid arthritis (RA), and interleukin-17 (IL-17) participates in RA pathology by affecting FLSs. The aims of this study were to investigate the effects of IL-17 on the proliferation and autophagy of FLSs and the role of signal transducer and activator of transcription-3 (STAT3) in RA. FLSs were treated with IL-17 at different concentrations (0, 1, 10, and 20 ng/mL); then, autophagy was assayed with western blotting, immunofluorescence, and transmission electron microscopy. The effects of IL-17 on FLSs proliferation were measured with the Cell Counting Kit-8 assay and flow cytometry to analyze cell cycle distribution, and proliferating cell nuclear antigen (PCNA) was detected by western blotting. The autophagy inhibitors, 3-methyladenine (3-MA) and chloroquine (CQ), were used to determine the effect of autophagy on proliferation in IL-17-treated FLSs. Finally, the STAT3 inhibitor STA21 was used to examine the relationship between STAT3 and autophagy in IL-17-treated FLSs. Our results showed that IL-17 positively affected autophagy and proliferation in FLSs. Inhibition of autophagy suppressed the IL-17-mediated proliferation of FLSs. Additionally, suppression of STAT3 activation decreased autophagy in IL-17-treated FLSs. Our findings showed that IL-17 promoted the tumor-like proliferation of FLSs by upregulating autophagy via STAT3 activation.