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The pore habits of gas hydrate in natural sediment matrices provide essential clues for understanding physical (mechanical, thermal, hydraulic, and electrical) properties of hydrate-bearing sediments, yet there are no tools that can directly visualize the pore habits of natural gas hydrate other than indirect interpretation based on core-scale or field-scale observations. A significant challenge is to obtain a mini-core from pressure cores retrieved from natural reservoirs for high-resolution micro-CT (computed tomography) scans while maintaining pressure and temperature conditions required for stability of gas hydrate during all operational steps including manipulation, cutting, transferring, sub-coring and CT scanning. We present a new set of tools for pore-scale micro-CT imaging of natural hydrate-bearing sediments while maintaining pressure and temperature control. The tests with laboratory-prepared cores and pressure cores successfully demonstrate the capability of this set of tools to subsample a mini-core from pressure cores, transfer the mini-core to an X-ray transparent core holder, and conduct micro-CT scans. Successfully obtained CT images prove the functionality of this set of tools.

A novel chip-scale metal-dielectric-metal (MDM) refractive-index sensor is proposed and investigated in this paper by using finite-difference time-domain (FDTD) method and multimode interference coupled-mode theory (MICMT), respectively. A slot cavity with an embedded tooth-shape cavity and a side-coupled semi-ring cavity are inserted between the input and output MDM waveguides. According to the simulation results, dual ultra-sharp and asymmetrical Fano peaks emerge in transmission spectrum with high performances. Besides, the transmission responses for the primary parameters of this structure are also investigated. To focus on developing integrated photonic devices, the original structure is successfully expanded by two additional semi-ring cavities through an innovative coupling approach, generating up to eight Fano peaks with outstanding characteristics. It is believed that this novel MDM structure will be a guideline for designing the chip-scale plasmonic devices.

Microstructures are fabricated with a fast fabrication speed, submicron-scale precision and a minimum feature size of 1.5 μm. The proposed rapid prototyping fabrication method takes advantage of the maskless lithography technique based on a digital mirror device (DMD) and photocurable resin, which has a broad range of uses in three-dimensional (3D) printing. To illustrate the feasibility of this method, a Dammann grating is fabricated. Using a series of experiments and optimized designs, we analyze the characteristics of the photocurable resin, quantify the dose modulation for lithography and redesign the mask pattern. Consequently, a Dammann grating with a 50% diffraction efficiency is successfully fabricated, which can not only guarantee the precision but also maintain the fabrication speed. This work demonstrates the potential of this method to rapidly and directly manufacture binary optical elements or structures at the nanoscale based on photocurable resin and DMD-based maskless lithography.

In order to design a five-port grating with good uniformity, a single-groove reflective beam splitter with an incident wavelength of 1550 nm is designed. The incident structure is under normal incidence. We get better optimized parameters by rigorous coupled waves. The five diffraction order efficiencies of the grating are each close to 20%. The optimized data shows that grating structure has high efficiency and high tolerance, which will have good application value in the field of beam splitter. Furthermore, by investigating the coupling overlap integration and field distribution, the mechanism can be well explained for such a grating.

The physical properties of natural gas hydrate-bearing sediments are critical for the analysis of natural systems and for the design of gas production strategies. This work explores the properties of fine-grained sediments containing segregated hydrate lenses. Our analyses show that hydrate formation is grain-displacive when the product of the effective stress and the grain radius is σ′R

Purpose: The objective of this study was to predict the preoperative pathological grading and survival period of Pseudomyxoma peritonei (PMP) by establishing models, including a radiomics model with greater mental caking as the imaging observation index, a clinical model including clinical indexes, and a combination model of these two.Methods: A total of 88 PMP patients were selected. Clinical data of patients, including age, sex, preoperative serum tumor markers [CEA, CA125, and CA199], survival time, and preoperative computed tomography (CT) images were analyzed. Three models (clinical model, radiomics model and joint model) were used to predict PMP pathological grading. The models’ diagnostic efficiency was compared and analyzed by building the receiver operating characteristic (ROC) curve. Simultaneously, the impact of PMP’s different pathological grades was evaluated.Results: The results showed that the radiomics model based on the CT’s greater omental caking, an area under the ROC curve ([AUC] = 0.878), and the combined model (AUC = 0.899) had diagnostic power n for determining PMP pathological grade.Conclusion: The imaging radiomics model based on CT greater omental caking can be used to predict PMP pathological grade, which is important in the treatment selection method and prognosis assessment.

All-optical controllable photonic devices have attracted more and more attention for their excellent performances of all-optical controllability, without mechanical structure, high compactness, fast response speed and stable regulation. Here, we will present our recent research achievements in graphene enabled all-optical controllable photonic devices and their applications in filter and sensor.

A submarine cable monitoring system based on enhanced coherent optical time-domain reflectometry (E-COTDR) is realized. An improved optimal peak-seeking (OPS) based I/Q demodulation method is employed for simultaneous loss measurement and vibration monitoring. A single-end diagnosis range over 74km is achieved for the proposed E-COTDR, enabling the double-end cooperative system to have a single-span of 148km. For the multi-span cascaded cables over 1000km, the loss and vibration monitoring without fading zone is carried out for a single-span of 121km. The proposed system provides a reliable technical option for the next generation underwater cable monitoring applications.

In this paper, we aim to achieve effective image representation for image retrieval in an unsupervised manner. To this end, we propose a fully cross-dimensional weighting pooling (FCroW) method to improve the weight strategy of the cross-dimensional weighting pooling (CroW). More specifically, FCroW weights both the non-zero parts and zero-parts of convolutional layers, aiming to obtain robust image representations. In particular, we aggregate multi-scale features extracted by convolutional neural networks using the proposed FCroW, taking into account multiple aspects of visual features captured by the networks. Different weights can be assigned to the features extracted by different layers of the networks. To reduce the effort for parameter tuning, we propose an initial strategy to prune the searching space of the weights, which is achieved by designing constraint rules based on the prior knowledge on relations between the layers of the networks. Based on this, we propose weighted multi-layer feature fusion for similar image representations. Extensive experiments conducted on four public real-world datasets demonstrate the effectiveness of the proposed FCroW method and the pruning strategy for image retrieval.

In this paper, we investigate and analyze numerically and theoretically a coupled plasmonic resonant system by using finite-difference time-domain (FDTD) method and multimode interference coupled-mode theory (MICMT), respectively. First, by employing an end-coupled cavity associated with two side-coupled cavities, three ultra-sharp and asymmetrical Fano resonant peaks are observed in the transmission spectrum. High refractive index sensitivities and high figure of merits are achieved for all the peaks. In the interest of highly integrated optical devices, up to seven Fano peaks with asymmetrical line shapes are achieved when the composite structure is successfully extended by two additional cavities, whereas most of the reported results are about 1-4 Fano resonances in a single structure. Preferred performances are also obtained for this chip-scale structure. This proposed structure may have great potential applications for on-chip optical sensing and optical communication in highly integrated photonic circuits.

Background: We aimed to establish a new approach for surveillance of cancer prevalence and survival in China, based on the Medical-Insurance-System-based Cancer Surveillance System (MIS-CASS). Methods: We constructed a standard procedure for data collection, cleaning, processing, linkage, verification, analysis, and estimation of cancer prevalence and survival (including both actual observations and model estimates) by conjoint use of medical insurance claims data and all-cause death surveillance data. As a proof-of-principle study, we evaluated the performance of this surveillance approach by estimating the latest prevalence and survival for upper gastrointestinal cancers in Hua County, a high-risk region for oesophageal cancer in China. Findings: In Hua County, the age-standardised relative 5-year survival was 39·2% (male: 36·8%; female: 43·6%) for oesophageal cancer and 33·3% (male: 29·6%; female: 43·4%) for stomach cancer. For oesophageal cancer, better survival was observed in patients of 45–64 years compared with national average estimates, and women of

The machining of mechanical parts needs to go through cutting, grinding and other processes, but it is often necessary to spray anti rust paint after forming to achieve the anti rust effect. However, it takes a long time for mechanical parts to dry naturally after painting, which affects the production efficiency. In order to accelerate the drying process of antirust paint and shorten the processing cycle of mechanical parts, it is necessary to dry the mechanical parts with the help of drying device. In the existing technology, the drying device mostly places the mechanical parts with drying on the conveyor belt or drying table, and then uses the heating device to dry them. This mode can only dry one side of the mechanical parts each time, and can not dry the mechanical parts in three dimensions, so the drying efficiency is low. Therefore, we provide a drying device for machining parts.

With the improvement of living standards, foods with high sugar content will bring oral health problems, so the problem of 3D reconstruction of teeth is derived. Human denture has the characteristics of complex curved surface, high manufacturing accuracy and complex measurement. Alginate materials are widely used in mainstream dental clinics to act on patients' oral cavity. The denture models are obtained by multiple occlusions of the upper and lower jaw of the patients, and then sent to the processing plant for manufacturing, and finally polished, which takes about 3 to 7 days. The abovementioned processing plants often use the method of impression filling, which will produce great error during the processing, and even in the later stage of model dressing, it can not achieve high precision. Therefore, accurate measurement of human denture is the key factor of tooth preparation.

Feeding refers to putting materials into machines for processing. However, with the development of society, more and more materials are needed. However, the efficiency of manual feeding is too low to meet the needs of production. In the process of mechanical processing, it is usually necessary to process parts or structures for stamping. The existing mechanical processing and stamping equipment adopts manual feeding, which not only has low efficiency, but also has great danger and high production cost. To solve the problems raised in the background technology, an improved feeding device for machining is proposed.

To understand the influence of the text representation of vertigo interrogation texts on classification results, our paper proposes a fusion strategy of text representation combination and constructs a new stacking model fusion. Vertigo interrogation texts of the four typical vertigo diseases are used to make classification under the different text representation. Results show that the classification effect of proposed stacking model fusion with proposed text representation combinations is superior to that of the gradient boosting decision tree, support vector machine, and naive Bayes with the simple text representation. Results also show that the proposed text representation combination of word2vec, GloVe and one-hot is the best overall classification effect among other text representation combinations based on our proposed stacking model fusion. Therefore, we conclude that the proposed fusion strategy of text representation combination and stacking model fusion can improve the classification effect of text representation of vertigo interrogation texts.

Beauty and Personal care product retrieval has attracted more and more attention due to its wide application value. However, due to the diversity of data and the complexity of image background, this task is very challenging. In this paper, we propose a multi-feature fusion method based on salient object detection to improve retrieval performance. The key of our method is to extract the foreground objects of the query set by using the salient object detection network, so as to eliminate the background interference. Then the foreground target images and dataset are put into the multi-classification networks to extract multiple fusion features for retrieval. We use the perfect-500k dataset for experiments, and the results show that our method is effective. Our method ranked 2st in the Grand Challenge of AI Meets Beauty in ACM Multimedia 2020 with a MAP score of 0.43729. We released our code on GitHub:github.com/R-M-Yan/ACMMM2020AIMeetBeauty.

Highlights • Code comparisons build confidence in simulators to model interdependent processes. • International hydrate reservoir simulators are compared over five complex problems. • Geomechanical processes significantly impact response of gas hydrate reservoirs. • Simulators yielded comparable results, however many differences are noted. • Equivalent constitutive models are required to achieve agreement across simulators. Geologic reservoirs containing gas hydrate occur beneath permafrost environments and within marine continental slope sediments, representing a potentially vast natural gas source. Numerical simulators provide scientists and engineers with tools for understanding how production efficiency depends on the numerous, interdependent (coupled) processes associated with potential production strategies for these gas hydrate reservoirs. Confidence in the modeling and forecasting abilities of these gas hydrate reservoir simulators (GHRSs) grows with successful comparisons against laboratory and field test results, but such results are rare, particularly in natural settings. The hydrate community recognized another approach to building confidence in the GHRS: comparing simulation results between independently developed and executed computer codes on structured problems specifically tailored to the interdependent processes relevant for gas hydrate-bearing systems. The United States Department of Energy, National Energy Technology Laboratory, (DOE/NETL), sponsored the first international gas hydrate code comparison study, IGHCCS1, in the early 2000s. IGHCCS1 focused on coupled thermal and hydrologic processes associated with producing gas hydrates from geologic reservoirs via depressurization and thermal stimulation. Subsequently, GHRSs have advanced to model more complex production technologies and incorporate geomechanical processes into the existing framework of coupled thermal and hydrologic modeling. This paper contributes to the validation of these recent GHRS developments by providing results from a second GHRS code comparison study, IGHCCS2, also sponsored by DOE/NETL. IGHCCS2 includes participants from an international collection of universities, research institutes, industry, national laboratories, and national geologic surveys. Study participants developed a series of five benchmark problems principally involving gas hydrate processes with geomechanical components. The five problems range from simple geometries with analytical solutions to a representation of the world's first offshore production test of methane hydrates, which was conducted with the depressurization method off the coast of Japan. To identify strengths and limitations in the various GHRSs, study participants submitted solutions for the benchmark problems and discussed differing results via teleconferences. The GHRSs evolved over the course of IGHCCS2 as researchers modified their simulators to reflect new insights, lessons learned, and suggested performance enhancements. The five benchmark problems, final sample solutions, and lessons learned that are presented here document the study outcomes and serve as a reference guide for developing and testing gas hydrate reservoir simulators.

Importance Lymphopenia is common and correlates with poor clinical outcomes in patients with coronavirus disease 2019 (COVID-19). Objective To determine whether a therapy that increases peripheral blood leukocyte and lymphocyte cell counts leads to clinical improvement in patients with COVID-19. Design, Setting and Participants Between February 18 and April 10, 2020, we conducted an open-label, multicenter, randomized clinical trial at 3 participating centers in China. The main eligibility criteria were pneumonia, a blood lymphocyte cell count of 800 per μL (to convert to ×109/L, multiply by 0.001) or lower, and no comorbidities. Severe acute respiratory syndrome coronavirus 2 infection was confirmed with reverse-transcription polymerase chain reaction testing. Exposures Usual care alone, or usual care plus 3 doses of recombinant human granulocyte colony-stimulating factor (rhG-CSF, 5 μg/kg, subcutaneously at days 0-2). Main Outcomes and Measures The primary end point was the time from randomization to improvement of at least 1 point on a 7-category disease severity score. Results Of 200 participants, 112 (56%) were men and the median (interquartile range [IQR]) age was 45 (40-55) years. There was random assignment of 100 patients (50%) to the rhG-CSF group and 100 (50%) to the usual care group. Time to clinical improvement was similar between groups (rhG-CSF group median of 12 days (IQR, 10-16 days) vs usual care group median of 13 days (IQR, 11-17 days); hazard ratio, 1.28; 95% CI, 0.95-1.71;P = .06). For secondary end points, the proportion of patients progressing to acute respiratory distress syndrome, sepsis, or septic shock was lower in the rhG-CSF group (rhG-CSF group, 2% vs usual care group, 15%; difference, −13%; 95%CI, −21.4% to −5.4%). At 21 days, 2 patients (2%) had died in the rhG-CSF group compared with 10 patients (10%) in the usual care group (hazard ratio, 0.19; 95%CI, 0.04-0.88). At day 5, the lymphocyte cell count was higher in the rhG-CSF group (rhG-CSF group median of 1050/μL vs usual care group median of 620/μL; Hodges-Lehmann estimate of the difference in medians, 440; 95% CI, 380-490). Serious adverse events, such as sepsis or septic shock, respiratory failure, and acute respiratory distress syndrome, occurred in 29 patients (14.5%) in the rhG-CSF group and 42 patients (21%) in the usual care group. Conclusion and Relevance In preliminary findings from a randomized clinical trial, rhG-CSF treatment for patients with COVID-19 with lymphopenia but no comorbidities did not accelerate clinical improvement, but the number of patients developing critical illness or dying may have been reduced. Larger studies that include a broader range of patients with COVID-19 should be conducted. Trial Registration Chinese Clinical Trial Registry:ChiCTR2000030007

Retrieving cases with similar image features has been found to be effective for improving the diagnostic accuracy of microcalcification (MC) lesions in mammograms. However, a major challenge in such an image-retrieval approach is how to determine a retrieved lesion image has diagnostically similar features to that of a query case. We investigate the feasibility of modeling perceptually similar MC lesions by using deep learning features extracted from two types of deep neural networks, of which one is a supervised-learning network developed for the task of MC detection and the other is a denoising autoencoder network. In the experiments, the deep learning features were compared against the perceptual similarity scores collected from a reader study on 1,000 MC lesion image pairs. The results indicate that the deep learning features can potentially be more effective for modelling the notion of perceptual similarity of MC lesions than traditional handcrafted texture features.

Summary: Background: We aimed to establish a Medical-Insurance-System-based Cancer Surveillance System (MIS-CASS) in China and evaluate the completeness and timeliness of this system through reporting cancer incidence rates using claims data in two regions in northern and southern China. Methods: We extracted claims data from medical insurance systems in Hua County of Henan Province, and Shantou City in Guangdong Province in China from Jan 1, 2012 to Jun 30, 2019. These two regions have been considered to be high risk regions for oesophageal cancer. We developed a rigorous procedure to establish the MIS-CASS, which includes data extraction, cleaning, processing, case ascertainment, privacy protection, etc. Text-based diagnosis in conjunction with ICD-10 codes were used to determine cancer diagnosis. Findings: In 2018, the overall age-standardised (Segi population) incidence rates (ASR World) of cancer in Hua County and Shantou City were 167·39/100,000 and 159·78/100,000 respectively. In both of these areas, lung cancer and breast cancer were the most common cancers in males and females respectively. Hua County is a high-risk region for oesophageal cancer (ASR World: 25·95/100,000), whereas Shantou City is not a high-risk region for oesophageal cancer (ASR World: 11·43/100,000). However, Nanao island had the highest incidence of oesophageal cancer among all districts and counties in Shantou (ASR World: 36·39/100,000). The age-standardised male-to-female ratio for oesophageal cancer was lower in Hua County than in Shantou (1·69 vs. 4·02). A six-month lag time was needed to report these cancer incidences for the MIS-CASS. Interpretation: MIS-CASS efficiently reflects cancer burden in real-time, and has the potential to provide insight for improvement of cancer surveillance in China. Funding: The National Key R&D Program of China (2016YFC0901404), the Digestive Medical Coordinated Development Center of Beijing Municipal Administration of Hospitals (XXZ0204), the Sanming Project of Shenzhen (SZSM201612061), and the Shantou Science and Technology Bureau (190829105556145, 180918114960704). Keywords: Medical insurance system, Claims data, Cancer surveillance, Cancer incidence, China

Since December 2019, when coronavirus disease 2019 (Covid-19) emerged in Wuhan city and rapidly spread throughout China, data have been needed on the clinical characteristics of the affected patients.We extracted data regarding 1099 patients with laboratory-confirmed Covid-19 from 552 hospitals in 30 provinces, autonomous regions, and municipalities in mainland China through January 29, 2020. The primary composite end point was admission to an intensive care unit (ICU), the use of mechanical ventilation, or death.The median age of the patients was 47 years; 41.9% of the patients were female. The primary composite end point occurred in 67 patients (6.1%), including 5.0% who were admitted to the ICU, 2.3% who underwent invasive mechanical ventilation, and 1.4% who died. Only 1.9% of the patients had a history of direct contact with wildlife. Among nonresidents of Wuhan, 72.3% had contact with residents of Wuhan, including 31.3% who had visited the city. The most common symptoms were fever (43.8% on admission and 88.7% during hospitalization) and cough (67.8%). Diarrhea was uncommon (3.8%). The median incubation period was 4 days (interquartile range, 2 to 7). On admission, ground-glass opacity was the most common radiologic finding on chest computed tomography (CT) (56.4%). No radiographic or CT abnormality was found in 157 of 877 patients (17.9%) with nonsevere disease and in 5 of 173 patients (2.9%) with severe disease. Lymphocytopenia was present in 83.2% of the patients on admission.During the first 2 months of the current outbreak, Covid-19 spread rapidly throughout China and caused varying degrees of illness. Patients often presented without fever, and many did not have abnormal radiologic findings. (Funded by the National Health Commission of China and others.).

Activated hidden units in convolutional neural networks (CNNs), known as feature maps, dominate image representation, which is compact and discriminative. For ultra-large datasets, high dimensional feature maps in float format not only result in high computational complexity, but also occupy massive memory space. To this end, a new image representation by aggregating convolution kernels (ACK) is proposed, where some convolution kernels capturing certain patterns are activated. The top-n index numbers of the convolution kernels are extracted directly as image representation in discrete integer values, which rebuild relationship between convolution kernels and image. Furthermore, a distance measurement is defined from the perspective of ordered sets to calculate position-sensitive similarities between image representations. Extensive experiments conducted on Oxford Buildings, Paris, and Holidays, etc., manifest that the proposed ACK achieves competitive performance on image retrieval with much lower computational cost, outperforming the ones using feature maps for image representation.

BackgroundThe coronavirus disease 2019 (COVID-19) outbreak is evolving rapidly worldwide.ObjectiveTo evaluate the risk of serious adverse outcomes in patients with COVID-19 by stratifying the comorbidity status.MethodsWe analysed data from 1590 laboratory confirmed hospitalised patients from 575 hospitals in 31 provinces/autonomous regions/provincial municipalities across mainland China between 11 December 2019 and 31 January 2020. We analysed the composite end-points, which consisted of admission to an intensive care unit, invasive ventilation or death. The risk of reaching the composite end-points was compared according to the presence and number of comorbidities.ResultsThe mean age was 48.9 years and 686 (42.7%) patients were female. Severe cases accounted for 16.0% of the study population. 131 (8.2%) patients reached the composite end-points. 399 (25.1%) reported having at least one comorbidity. The most prevalent comorbidity was hypertension (16.9%), followed by diabetes (8.2%). 130 (8.2%) patients reported having two or more comorbidities. After adjusting for age and smoking status, COPD (HR (95% CI) 2.681 (1.424–5.048)), diabetes (1.59 (1.03–2.45)), hypertension (1.58 (1.07–2.32)) and malignancy (3.50 (1.60–7.64)) were risk factors of reaching the composite end-points. The hazard ratio (95% CI) was 1.79 (1.16–2.77) among patients with at least one comorbidity and 2.59 (1.61–4.17) among patients with two or more comorbidities.ConclusionAmong laboratory confirmed cases of COVID-19, patients with any comorbidity yielded poorer clinical outcomes than those without. A greater number of comorbidities also correlated with poorer clinical outcomes.

This paper designs a five-port transmission grating under normal incidence. Rigorous coupled-wave approach is used to optimize the grating parameters. The energy of the grating is mainly dispersed to the 0th, ±1st and ±2nd orders. The efficiency of each diffraction order under both polarizations is close to 20%. The modal method is used to describe the propagation mechanism of the two polarized lights in the grating, and the diffraction behavior of the grating is analyzed. In addition, the grating has a wide range of incident characteristics and a large process tolerance. Therefore, this five-port beam splitter with a connecting layer will be a good polarization-independent beam splitting device.

Li, L.; Lei, L., and Han, D., 2018. Regional green innovation efficiency in high-end manufacturing. In: Ashraf, M.A. and Chowdhury, A.J.K. (eds.), Coastal Ecosystem Responses to Human and Climatic Changes throughout Asia.Using regional panel data of the high-end manufacturing industry in China from 2011 to 2015, the authors use projection tracking and a stochastic frontier model to analyze regional green innovation efficiency and influencing factors. Research shows that the innovation efficiency national average in high-end manufacturing is between 0.7 and 0.8 and that regional green innovation efficiency is polarized, presenting as high in the east and low in the west. Both of these measures illustrate some room for green innovation improvement. The number of research and development institutions and industry agglomeration have a significant positive influence on green innovation, while government funding plays a supporting role. Environmental regulation, market maturity, and degree of openness to the outside world have some negative effects on green innovation, with environmental regulation having significant effects. This paper provides evidence for the improvement of green innovation efficiency in the high-end manufacturing industry in China.

A polarization-independent ultra-broadband T-type absorber with doped silicon in the terahertz band is proposed, which consists of T-shaped Si/SiO2 arrays. The results show that the absorption is more than 95% at 1.0–5.3 THz. Such an absorber can have a center frequency and relative bandwidth ratio of 3.15 THz and 137%. In addition, the absorption of 90% can be achieved at 1.0–5.3 THz with the incident angle of 0–44°. The energy distribution of the electromagnetic field at the peak of the ultra-broadband absorber is clearly explained by finite element method. Furthermore, compared with the proposed reference planar absorber and the reported broadband absorber, the T-type absorber in this work has better absorption bandwidth, center frequency, and relative bandwidth ratio. The impedance of T-type terahertz absorber is demonstrated well by impedance matching theory. It is believed that the ultra-wideband terahertz absorber with silicon doped based on periodic T-shaped arrays has great potential in the wideband terahertz absorber field and can be applied in the biomedical field.

An enhanced newly high-efficiency dual-function beam splitter of the grating is described in this paper. The proposed grating can realize newly dual-function at infrared wavelength under second Bragg incidence, which can function as high-efficiency component for TE polarization. Moreover, under TM polarization, the grating is different from the other traditional dual-function grating, which can achieve a three-port output with high efficiency and good uniformity. By using the finite element method, an optimum grating structure can be presented with the efficiency of three diffraction orders (0th, −1st, −2nd) for TM polarization greater than 30%. As for TE polarization, the efficiency of −2nd order will be better than 95% with a wide bandwidth. Therefore, the proposed grating can be well applied in variety optical fields.

MTS-810 material testing machine and acoustic emission signal analyzer were adopted to explore the mechanical behavior of concrete beams broken by the static load and the nonlinear cumulative damage law of concrete beams broken by fatigue bending from single-stage loading. Then, by introducing the Ramesh Talreja’s Damage Criterion, the damage rule of single-stage loading was extended to the damage accumulation rule under multi-stage loading, and the results were verified by the results of two-stage and three-stage fatigue loading tests. Two main conclusions are achieved: first, affected by four-point bending load, the fatigue life of the concrete specimen is in line with the law of the two-parameter Weibull distribution, namely the higher the stress level is, the shorter the fatigue life is. Second, an obvious nonlinear relationship was discovered in the damage of concrete. The model deduced in this paper and the Palmgren-Miner linear damage accumulation model were adopted to compare the test results of flexural fatigue under single, two and three stage loads. The calculation results of this model were more reliable.

Widely tunable distributed feedback (DFB) lasers based on surface isolation grooves were developed using i-line lithography. Periodic p-electrodes on mesas enabled the realization of a great tunability. It is to be mentioned that, our device reached a wavelength tuning range of approximately 17.5 nm by only one pair of electrodes under both temperature and current variation with the help of order hop. A single longitudinal mode with continuous-wave output power reached up to 132.8 mW/facet for a drive current of 400 mA at 20 °C. The side-mode suppression ratio reached 36.25 dB. The wide tuning range and the simple fabrication steps promise our device an immense potential as light source in many applications such as atomic clocks and gas sensing.

Glare reduction is the focus of much attention in the field of optical engineering owing to its vital role in high-quality image acquisition in photoelectric visual inspection technology. Based on Fresnel reflection theory, we have derived a polarization factor related to the glare intensity distribution and have obtained theoretical results showing that the factor plays a leading role in reducing glare. Based on the image detection model, we have derived a displacement factor which determines the position and the size of the glare area, and have obtained theoretical results showing that the factor plays a supporting role in reducing glare. The image gray-scale transformation curve is obtained by sampling image data under the different polarization and positions. And these image data are measured from certain object in the equivalent environment while the different conditions. Then the theories above have been justified and the whole theory of the polarization-based glare elimination method has been interpreted completely via actual experiments in glare elimination. As a result, reducing the intensity contrast between the glare area and its neighboring area is proved to be the essence of glare elimination. Furthermore, the glare can be nearly eliminated perfectly by adjusting the polarization factor and the displacement factor.

// Yong Yan 1, * , Jian-Yong Luo 1, * , Yin Chen 2, * , Heng-Hui Wang 1 , Guo-Ying Zhu 1 , Pei-Yan He 1 , Jin-Lei Guo 1 , Yong-Liang Lei 3 and Zhong-Wen Chen 1 1 Jiaxing Key Laboratory of Pathogenic Microbiology, Jiaxing Municipal Center for Disease Control and Prevention, Jiaxing 314050, China 2 Institute of Microbiology, Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou 310051, China 3 Lishui Municipal Center for Disease Control and Prevention, Lishui 323000, China * These authors contributed equally to this work Correspondence to: Zhong-Wen Chen, email: heton74@hotmail.com Keywords: Luminex, xMAP, respiratory virus, real-time RT-PCR, multiplex detection Received: December 30, 2016 Accepted: June 02, 2017 Published: June 17, 2017 ABSTRACT We utilized one-step multiplex reverse transcription-PCR (RT-PCR) and Luminex xMAP technology to develop a respiratory multiplex liquid-chip assay (rMLA) for simultaneous detection of 6 common respiratory viruses, including influenza virus type A (FluA) and type B (FluB), para-influenza virus type 3 (PIV-3), respiratory syncytial virus (RSV), human metapneumovirus (MPV) and a threatening virus to China, Middle East Respiratory Syndrome coronavirus (MERS-CoV). Performance of rMLA was evaluated by comparing with real-time RT-PCR. Detection data from clinical specimens showed that the rMLA had diagnostic sensitivities of 97.10% for FluA, 94.59% for FluB, 98.68% for PIV-3, 94.87% for RSV and 95.92% for MPV (No Data for MERS-CoV due to the lack of positive specimens). Data of analytical sensitivities showed that the detection limits of the rMLA assay were 5–25 viral RNA copies per μl for FluA, FluB, PIV-3 and MERS-CoV, approximate to the real-time RT-PCR assay; while the values were 8 and 22copies/μl for MPV and RSV, lower than the real-time RT-PCR(78 and 114 copies/μl respectively). The results indicated that the rMLA is a sensitive, specific detection tool and comparable to real-time RT-PCR, especially suitable for high-throughput detection of respiratory specimens.

Though adding a groove to a plasmonic end-coupled perfect ring (PR) resonator, two additional resonance modes, which can be controlled by the length of the groove, will arise in this proposed ring-groove (RG) joint metal-insulator-metal (MIM) waveguide. By further cascading, the PR resonator and the RG joint resonator, single and dual Fano resonances with asymmetric line shapes are obtained due to the interference effects between the dark modes and the bright modes. High figure of merit and high refractive-index sensitivity are achieved, and thus this structure is suitable for the biochemistry sensing area. Interestingly, normal and abnormal dispersions are also investigated for the Fano peaks and dips, respectively. The performances of the proposed structure are investigated by using the finite-difference time-domain method.

The increasing demand of super large-scale spacecraft simulation and spacecraft multi-disciplinary collaborative simulation brings great pressure to the simulation system architecture. In order to satisfy the current complex simulation requirements, combined with cloud computing architecture and edge computing architecture, a new and efficient simulation architecture composed of core cloud, edge cloud, and user terminal is designed. The core cloud manages and monitors the edge cloud; the edge cloud allocates virtual resources and completes simulation; and user terminals provide users with portals for describing tasks and viewing results. The simulation system architecture integrating cloud and edge computing has the advantages of high resource utilization, quick service response, strong robustness, and simple promotion in other research fields. And it is great significance to improve simulation efficiency and conserve computing resources.

An under-voltage locking circuit for driving chip is designed to ensure the stability of the enhanced GaN HEMT driving voltage. Firstly, SPICE model of enhanced GaN HEMT device is used to build the circuit. The basic electrical characteristics of the device are analyzed. Then the parasitic inductance of the enhanced GaN HEMT device caused by PCB wiring and pad layout is simulated. According to the volt-ampere characteristics of parasitic PNP transistors in Shanghua CSMC 0.5um CMOS process, an under-voltage locking circuit with Schmidt flip-flops and inverters at the output end is designed which improves the driving ability of the circuit. When the power supply voltage rises/falls between 3-5V, the rising/falling threshold is 4.1V/3.7V, and the threshold hysteresis is 400mV. When the temperature changes from - 40°C to 125°C, there is a small temperature drift. This under voltage lock out circuit can effectively prevent the power supply from abnormal transition due to noise and load-induced interference and the incomplete conduction state of the enhanced GaN HEMT.

A chip-scale refractive index sensor based on multiple Fano resonances is proposed by using a metal-insulator-metal (MIM) structure, which is constructed by two side-coupled semi-ring cavities and a vertical cavity. The finite-difference time-domain method and multimode interference coupled-mode theory are employed to simulate and analyze the transmission spectra of this structure, respectively. First, dual Fano resonances are generated in the MIM structure with a baffle and a semi-ring cavity. By arranging two additional cavities, the mode interferences successfully induce up to six ultra-sharp and asymmetrical Fano peaks. The calculated sensing performances are available with ultra-high sensitivity of 1405 nm/RIU and figure of merit of 3.62×105. This chip-scale refractive index sensor may have great applications in highly integrated photonic circuits.

We evaluated characteristics and different prognostic factors for survival in age-stratified high-grade glioma in a US cohort. Eligible patients were identified in the Surveillance, Epidemiology, and End Results (SEER) registries and stratified into 3 age groups: 20-39 years old (1,043 patients), 40-59 years old (4,503 patients), and >60 years old (5,045 patients). Overall and cancer-related survival data were obtained. Cox models were built to analyze the outcomes and risk factors. It showed that race was a prognostic factor for survival in patients 40 to 59 years old and in patients ≥60 years old. Partial resection was associated with lower overall survival and cause-specific survival in all age groups (overall survival: 20-39 yr: HR=6.41; 40-59 yr: HR=4.84; >60 yr: HR=5.06; cause-specific survival: 20-39 yr: HR=5.87; 40-59 yr: HR=4.01; >60 yr: HR=3.36). The study highlights that, while some prognostic factors are universal, others are age-dependent. The effectiveness of treatment approaches differs for patients in different age groups. Results of this study may help to develop personalized treatment protocols for glioma patients of different ages.

In this study, a method is proposed for the rapid fabrication of a hexagonal compound eye microlens array (HCE-MLA) using maskless lithography technique based on digital micromirror device (DMD), in which a hexahedron array is lithographed, and subsequently, a microlens structure is lithographed layer by layer upon the hexahedron. Owing to the high filling rate of the hexagon and the aspheric surface of the paraboloid profile of the microlens, after the distribution of the required exposure dose of HCE-MLA was calculated based on dose modulation, a series of circular pattern with different radius could be obtained by equal-arc-mean slicing strategy that can adapt to the variable curvature of the target contour and improve its reconstruction precision. Then, after a hexagonal photoresist island was fabricated on the substrate, and the dose accumulated over multiple exposures, the required exposure dose profiles were reconstructed on the hexagonal photoresist island. Finally, a high-quality HCE-MLA with a smooth surface was fabricated via thermal reflow. The fabrication of the designed HCE-MLA using this method was demonstrated in experiments. The results indicate that the actual profile of HCE-MLA shows good agreement with the design profile and that simultaneously increasing the number of the slicing layers can improve the quality of the profile. The research indicated that this method is feasible and convenient for the fabrication of high-quality HCE-MLA.

Manipulation of femtosecond laser induced microstructures in glass by tuning the laser polarization has great potential in optics. Here we report two different polarization-dependent microstructures and their evolution with pulse repetition rate in an aluminosilicate glass induced by femtosecond laser irradiation. A V-shaped crack oriented parallel to the laser polarization plane is induced at the bottom of modified regions by pulses operated at 200 kHz, 1030 nm, and 300 fs. Further increasing the pulse repetition rate to 500 kHz leads to the formation of a dumbbell-shaped structure, which is elongated perpendicularly to the laser polarization, at the top of the modified region. The size of the coloration area and the dumbbell-shaped structure can be controlled by tuning the pulse duration. Further investigation indicates that higher numerical apertures are in favor of the presence of the polarization effects in femtosecond laser irradiation. The possible mechanism responsible for the formation of the two microstructures is discussed. These results could be helpful for understanding of ultrafast laser interaction with glass.

Four-port beam splitter with good uniformity was proposed by T-type double-layer with different dielectric grating. The total efficiency of the beam splitter is over 90% with beam splitting uniformity better than 3%. At the same time, the simplified modal analysis is added to calculate the grating mode and effective refractive index of the grating area, which clearly describes the physical propagation mechanism inside the grating. The finite element method is used to investigate the normalized field of the grating, which more intuitively reflects the way of energy transfer inside the grating. Finally, the incident characteristics and manufacturing tolerance of the grating are analyzed. Properties of the T-type grating were analyzed in three methods, which more fully illustrates the applicability and stability of the grating in this paper.

In fringe projection profilometry (FPP), objects with hole discontinuities can lead to shadows and even phase unwrapping morbidity. To solve this problem, we propose an enhanced FPP system by employing the backlighting technique in this paper. This method consists of shadow compensation (SC) and high dynamic range (HDR) imaging; the SC is implemented using the optimal mask, which is obtained by fusing two high-contrast images from different backlight intensities; the HDR imaging is performed by a multi-exposure technique to tackle the issue of multi-colored or specular reflections. Since the proposed method does not require complex phase-unwrapping algorithms, it is fast and robust for three-dimensional shape measurement of objects with hole discontinuities. To validate the method, morphological measurements of a wheel rim and a multi-colored human mask were performed. The results show that the proposed method can overcome discontinuity problems without degrading performance.

Through adding a groove to an end-coupled perfect ring (PR) resonator, a ring-groove (RG) joint metal-insulator-metal (MIM) structure is proposed. Destructive interference for the expected surface plasmon mode will occur due to the phase differences between two optical paths, leading to the plasmonic-induced absorption response with abnormal dispersion, which is analogous to the electromagnetically induced absorption in the three-level atomic system. A transmission dip is achieved at the former-peak wavelength of the PR resonator, while two transmission peaks arise around the window. The proposed structure, which benefits from -0.3 ps group delay time, will be preferred in the ultrafast-light applications. Due to the same interference effect, plasmonic-induced transparency response with slow-light characteristic is also investigated by arranging the RG joint resonator to be a side-coupled configuration. Therefore, a new approach for on-chip light-speed control can be developed by using the proposed structures, whose performances are investigated by the finite-difference time-domain (FDTD) method and the coupled mode theory.

A tunable multimode plasmonic filter is proposed by using a side-coupled ring-groove joint resonator. In addition to the integer resonance modes of the perfect ring resonator (RR), extra non-integer resonance modes are excited by adding a groove on the RR. According to the simulations with finite difference time domain method, it is investigated that two integer and two non-integer modes are obtained. When the groove is placed on the antinodes of the magnetic fields, the effective resonance lengths for the corresponding modes will be changed by the groove. In this case, one can linearly manipulate the wavelengths by changing the length of the groove. On the contrary, the wavelengths of the specific modes will be always fixed when the groove locates at the nodes of the modes. Compared to those perfect structured Fabry-Perot (FP) resonators, this compact device can provide more channels and manipulate the wavelengths flexibly. Therefore, it may find widely applications in the on-chip optical signal processing area.

The fused-silica sandwiched three-port grating under second Bragg angle incidence is presented with operation in transmission. To obtain a highly-efficient three-port grating for a working wavelength of 800 nm, the grating depth and period should be optimized by using rigorous coupled-wave analysis. With the optimized different three-port grating depths and periods, both TE-polarized and TM-polarized waves can be diffracted into three orders with nearly 33% efficiency for the given duty cycle of 0.6. Based on the grating parameters of numerical optimization, modal method may be employed to explain the physical mechanism of the beam propagation in the grating and analyze the splitting behavior. For the sandwiched three-port grating, it is feasible that the diffraction efficiencies can be enhanced for both TE and TM polarizations.

On the basis of single metal-insulator-metal (MIM) ring resonator (RR) structure, which acts as a band-stopped filter, a dual RR (DRR) system is proposed to obtain the plasmon-induced transparency (PIT) effect. By rotating the second RR an angle, double PIT windows are achieved due to the dual interference effects, which are attributed to different excitation pathways from the first RR to the second RR. In addition, triple PIT peaks are also achieved by adding an extra inclined RR to the DRR system. Phase shifts, which will occur at each transparency window, are also achieved and analyzed. These compact MIM waveguide structures may be used in the highly integrated optical circuits for biochemical sensors optical signal processing, and optical data storage.

BackgroundDuring the outbreak of coronavirus disease 2019 (COVID-19), consistent and considerable differences in disease severity and mortality rate of patients treated in Hubei province compared to those in other parts of China have been observed. We sought to compare the clinical characteristics and outcomes of patients being treated inside and outside Hubei province, and explore the factors underlying these differences.MethodsCollaborating with the National Health Commission, we established a retrospective cohort to study hospitalised COVID-19 cases in China. Clinical characteristics, the rate of severe events and deaths, and the time to critical illness (invasive ventilation or intensive care unit admission or death) were compared between patients within and outside Hubei. The impact of Wuhan-related exposure (a presumed key factor that drove the severe situation in Hubei, as Wuhan is the epicentre as well the administrative centre of Hubei province) and the duration between symptom onset and admission on prognosis were also determined.ResultsAt the data cut-off (31 January 2020), 1590 cases from 575 hospitals in 31 provincial administrative regions were collected (core cohort). The overall rate of severe cases and mortality was 16.0% and 3.2%, respectively. Patients in Hubei (predominantly with Wuhan-related exposure, 597 (92.3%) out of 647) were older (mean age 49.7 versus 44.9 years), had more cases with comorbidity (32.9% versus 19.7%), higher symptomatic burden, abnormal radiologic manifestations and, especially, a longer waiting time between symptom onset and admission (5.7 versus 4.5 days) compared with patients outside Hubei. Patients in Hubei (severe event rate 23.0% versus 11.1%, death rate 7.3% versus 0.3%, HR (95% CI) for critical illness 1.59 (1.05–2.41)) have a poorer prognosis compared with patients outside Hubei after adjusting for age and comorbidity. However, among patients outside Hubei, the duration from symptom onset to hospitalisation (mean 4.4 versus 4.7 days) and prognosis (HR (95%) 0.84 (0.40–1.80)) were similar between patients with or without Wuhan-related exposure. In the overall population, the waiting time, but neither treated in Hubei nor Wuhan-related exposure, remained an independent prognostic factor (HR (95%) 1.05 (1.01–1.08)).ConclusionThere were more severe cases and poorer outcomes for COVID-19 patients treated in Hubei, which might be attributed to the prolonged duration of symptom onset to hospitalisation in the epicentre. Future studies to determine the reason for delaying hospitalisation are warranted.