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Quantitative oxygen detection is of great importance in biological fields, complex environments, and chemical process engineering. Due to the high sensitivity and rapid response of long-lived phosp...

Image and sentence matching has attracted increasing attention since it is associated with two important modalities of vision and language. Previous methods aim to find the latent correspondences between image regions and words by aggregating the similarities of the region-word pairs. However, these approaches consider little about the relationships of diverse regions in the image and treat the similarities of all region-word pairs equally. Moreover, focusing on fine-grained alignment overly, the true meaning of the original image will be likely distorted. In this paper, a novel Region Reinforcement Network with Topic Constraint (RRTC) is proposed to explore the correspondences between images and texts. Specifically, the region reinforcement network is built to infer fine-grained correspondence by considering the relationships of regions and re-assigning region-word similarities. Meanwhile, the topic constraint module is presented to summarize the central theme of images, which constrains the original image deviation. Extensive experimental results on MSCOCO and Flickr30k datasets verify the effectiveness of our proposed RRTC.

Recently, visual question answering (VQA) based on the feature fusion between image vision and question text has attracted considerable research interests. The attention mechanism and dense iterative operations are adopted for fine-grained interplay and matching by aggregating the similarities of the image region and question word pairs. However, the autocorrelation information of image regions is ignored, which will lead to deviation in overall semantic understanding, thereby reducing the accuracy of answer prediction. Moreover, we notice that some valuable but unattended edge information of image is often completely forgotten after multiple bilateral co-attention operations. In this paper, a novel Compound-Attention Network with Original Feature injection is proposed to leverage both bilateral information and autocorrelation in a holistic deep framework. A visual feature enhancement mechanism is designed to mine more complete visual semantics and avoid understanding deviation. Then, an original feature injection module is proposed to retain the unattended edge information of the image. Extensive experiments conducted on VQA2.0 database demonstrate the effectiveness of the proposed method.

Background Ulcerative colitis (UC) is defined as a chronic inflammatory bowel disease that can occur in any part of the large bowel. In addition, UC affects only the large bowel except for backwash ileitis and pouchitis, whereas Crohn's disease (CD) affects the entire digestive tract. Inflammatory bowel disease (IBD) patients tend to be diagnosed with CD or indeterminate colitis when combined with gastric lesion. However, in recent years, some UC patients are reported to have various degrees of lesions in gastroduodenum. Here, we report a case of gastroduodenitis associated with UC (GDUC). Case summary A 25-year-old man with a history of Klippel-Trenaunay syndrome presented to the hospital with mucopurulent bloody stool and epigastric persistent colic pain for 2 wk. Continuous superficial ulcers and spontaneous bleeding were observed under colonoscopy. Subsequent gastroscopy revealed mucosa with diffuse edema, ulcers, errhysis, and granular and friable changes in the stomach and duodenal bulb, which were similar to the appearance of the rectum. After ruling out other possibilities according to a series of examinations, a diagnosis of GDUC was considered. The patient hesitated about intravenous corticosteroids, so he received a standardized treatment with pentasa of 3.2 g/d. After 0.5 mo of treatment, the patient's symptoms achieved complete remission. Follow-up endoscopy and imaging findings showed no evidence of recurrence for 26 mo. Conclusion The occurrence of gastrointestinal involvement in UC is rare, which may open a new window for studying the etiology and pathogenesis of UC. Physicians should consider broad differential diagnosis by endoscopic biopsy and laboratory examinations.

Semiconductor refrigeration utilizes Peltier effects to achieve cooling, and does not use any refrigerants. Due to its simple and compact structure, semiconductor refrigeration has become one of the most promising cooling technologies. However, as a semiconductor refrigeration system, the interactions among the main external factors that affect its performance are complicated. Based on experimental results and thermodynamic models, deeper insights are presented into semiconductor refrigeration in this study. Broader coupling between performance and main external parameters are analyzed, including the driving voltage of fans at both the hot and cold sides, and the working voltage of the semiconductor refrigeration chip. Optimal external parameters corresponding to a maximum COP and a maximum cooling capacity are obtained. For example, under the optimal working voltage of a semiconductor refrigeration chip with a fan driving voltage of 4 V at the hot side and 6 V at the cold side, Qc,max was increased by 60%, and was 326% higher than chips under 2 V and 10 V working voltages. Under the optimal fan driving voltage at the hot side with a 6 V fan driving voltage at the cold side and a 3 V working voltage of the chip, the maximum value of COP was respectively 140.3% and 104.3% larger than those with 0 V and 12 V fan driving voltages at the hot side. It is also found that the driving voltage of fans at the hot side has a greater influence on the optimal working voltage of a semiconductor refrigeration chip. This investigation could be applied in the optimization of the design and operational control of semiconductor refrigeration systems.

A new numerical method was proposed to describe the thermodynamic process of solidification and melting of alumina within discrete phase model (DPM). In this method, mushy region model which usually used in energy engineering was introduced in the calculation of phase transition and the effect of latent heat was calculated by defining the specific heat capacity of alumina particles. According to the comparison between cases which were no particle case, pure solid particles and phase transition involved case, several impacts on the flow field by particles were presented. The effect of solidification and melting process was concluded as the temperature lag around the melting point of alumina.

Finite element method is an efficient tool to investigate the biomechanics of human spine. The key to finite element method is to reconstruct a complete and accurate finite element model. In this study, a three-dimensional finite element model of thoracolumbar structure including complete pelvis (T12-pelvis) was built using computed tomography technology. The modeling process has been explained in detailed. During the process of validation, the model was assigned with non-linear material property for static or dynamic analyses. In static analysis, the vertebral geometry parameters of T12-L5, the axial displacement, the posterior disc bulge and the intradiscal pressure of intervertebral disc, range of motion under six loading cases and facet joint forces were obtained and compared with the experimental data. In dynamic analysis, motion segments were loaded with sinusoidal displacement at 1 Hz in the anterior-posterior and axial directions to verify the reaction force. The first-order resonant frequencies in the vertical direction from one motion segment and two motion segments to the entire model were obtained. The study provides a detailed and accurate method of validation to verify the finite element model of thoracolumbar spine.

Hydrodynamic force coefficients are important parameters in design and assessment of marine risers. The hydrodynamic coefficients are widely used for assessing marine riser responses due to floater motion excitation and vortex-induced vibrations (VIV). Traditionally, the hydrodynamic coefficients have been obtained from physical model tests on short rigid riser sections. Recently, the offshore industry has started to use computational fluid dynamics (CFD) analysis for predicting the hydrodynamic coefficients due to the recent advancement of CFD software and high-performance computing capabilities, but a reliable CFD modeling practice is requested for CFD analysis to be a more widely accepted prediction tool in the industry. A joint industry effort has been made for developing and verifying the reliable CFD modeling practice through a working group of the Reproducible Offshore CFD JIP. In the working group, a CFD modeling practice document was written based on existing practices already validated for model test data, and verified by blind validations with three CFD practitioners. The first year works are focused on the bare riser with circular cross-section, and the second year work will be extended to the other riser sections such as staggered buoyancy module and straked riser. This paper presents the working group’s first-year verification activities for a bare riser with circular cross-section. The verification works covers three test problems: 1) stationary simulation in steady current, 2) forced-oscillation in calm water, 3) forced-oscillation in steady current. In the stationary simulation, mean drag coefficient, standard deviation of lift coefficient, and Strouhal numbers are compared. In the forced-oscillation simulation in calm water, the fully-submerged riser section oscillates with a sinusoidal motion, and damping and added mass coefficients are compared. In the forced-oscillation simulation in current, the riser section oscillates in cross-flow direction to the steady current, and lift coefficient and added mass coefficient are compared. By following the modeling practice, the CFD predictions are consistent with each other and close to the model test data for a majority of test cases.

Addressing the phenomenon of data sparsity in hostile working conditions, which leads to performance degradation in traditional machine learning based fault diagnosis methods, a novel Wasserstein distance based Asymmetric Adversarial Domain Adaptation (WAADA) is proposed for unsupervised domain adaptation in bearing fault diagnosis. A GAN-based loss and asymmetric mapping are integrated to alleviate the difficulty of the training process in adversarial transfer learning, especially when the domain shift is serious. Moreover, simplified lightweight architecture is introduced to enhance the generalization and representation capability and reduce the computational cost. The experiment results show that our method not only achieves outstanding performance with sufficient data but also outperforms these prominent adversarial methods with limited data (both source and target domain), which provides a promising approach to the real industrial bearing fault diagnosis.

Highlights • We report one case of human rabies with a long incubation period in Wuhan, China. • In Wuhan, many free-roaming dogs are not only dangerous to domestic dogs and livestock, they are also a threat to humans. • Epidemiology of rabies with emphasis on its potential to spread in urban-rural fringe in Wuhan has been discussed. • The elimination of RABV from free-roaming domestic dogs will drive a considerable reduction in human disease. • We showed that the efficient collaboration was important between the hospital and a professional laboratory for rabies diagnosis., Rabies remains endemic in China and continues to pose a major threat to public health with a nearly 100 % case fatality rate in humans. We confirmed a case of human rabies in Wuhan, in May 2018. The patient had got a dog bite wound 3 years before symptoms of confusion, hydrophobia, and photophobia onset. On May 14, our laboratory confirmed that the patient was infected with a rabies virus that circulates in dogs in China and died on May 24, two weeks later after admission. Complete glycoprotein gene sequences determined for this isolate indicated the source of a RABV infection was dog-related RABV variants.

Through the analysis of real-time data and historical data mining in power grid operation, we can master the operation law of power grid, optimize the power system resources, and construct the technical support system of electric dispatching automation to improve the security and reliability of the power grid. This paper discusses the integration, storage, analysis and display technology of power big data. The technical support system based on big data technology includes the equipment maintenance management module, operation model management module, scheduling task management module and resource allocation management module. The experiment shows that TFFB of the system is always within the range of receiving in the case of high concurrent access, and the performance of the system can meet the application requirements.

To precisely measure the whole-surface characterization of freeform progressive addition lenses (PALs), considering the multi-optical-axis conditions is becoming particularly important. Spherical power and astigmatism (cylinder) measurements for freeform PALs, using a Hartmann–Shack wavefront sensor (HSWFS) are proposed herein. Conversion formulas for the optical performance results were provided as HSWFS Zernike polynomial expansions. For each selected zone, the studied PALs were placed and tilted to simulate the multi-optical-axis conditions. The results of two tested PALs were analyzed using MATLAB programs and represented as contour plots of the spherical equivalent and cylinder of the whole-surface. The proposed experimental setup can provide a high accuracy as well as a possibility of choosing 12 lines and positions of 193 measurement zones on the entire surface. This approach to PAL analysis is potentially an efficient and useful method to objectively evaluate the optical performances, in which the full lens surface is defined and expressed as the contour plots of power in different regions (i.e., the distance region, progressive region, and near region) of the lens for regions of interest.

With the development of the Internet of Things (IoT), the cloud data centers have already been an important foundation to support IoT data analysis and data-driven IoT services. For the data-driven services provision, cloud resources are necessary for the service components in the form of virtual machines (VMs). At the same time, there is a frequent data transmission among the service components (or VMs). Hence, to reduce the IoT services’ response time, it is critical to improve the network issue and avoid network bottleneck during resource allocation. In this paper, we investigate the VM placement problem for balanced network utilization by avoiding network congestion. We first use the resource topology model to represent user requests and formulate the problem formally. We prove that the problem is NP-hard and present a heuristic algorithm based on the resource topologies. The core idea is to analyze the global and required resource topologies and place the required VMs into multiple servers with lower communication cost. We conduct extensive simulations, and the simulation results show that our algorithms have significant performance improvement on reducing network occupation and IoT service delay compared to the best-fit strategy and divide-and-conquer strategy.

The gate system is used to estimate the direction of RFID tags carriers when they are going through the gate. Normally, it is difficult to achieve and keep a high accuracy in estimating motion dire...

Apatinib is a novel oral tyrosine kinase inhibitor targeting vascular endothelial growth factor receptor-2, which has been proved by clinical trials to be effective and safe for patients with chemotherapy-refractory gastric cancer. To date, there is no study or case report on apatinib treatment for patients with ovarian cancer. Here, we present the case of a 50-year-old Chinese woman with advanced ovarian cancer, who received apatinib at a daily dose of 500 mg for 28 days per cycle after failure of fourth-line chemotherapy. Favorable oncologic outcome was achieved in this case after treatment with apatinib. The patient’s progression-free survival is now 11.3 months, and she is taking apatinib and capecitabine as maintenance treatment. The common side effect of apatinib was fatigue; however, the toxicity of apatinib was controllable and tolerable. Thus, apatinib may be an option for chemotherapy-refractory advanced epithelial ovarian cancer, but this still warrants further investigation.

Representation based classifications are extensively used in many applications and have achieved remarkable successes. However, they still suffer from some problems. In one respect, the coefficients obtained are not competitive, which is not beneficial for classification. Also, the intrinsic manifold structure is not taken into consideration. It has been shown that the manifold smoothness is important for classification. To this end, based on collaborative representation, a new algorithm coined Manifold Smoothed Class-specific Discriminant Collaborative Representation, MSCDCR, for short, is proposed. Besides manifold structure, MSCDCR employs the whole training samples to code the test sample in a linear way, so that it can tell which class has the most similarity. The method proposed can reduced to a closed-form solution, which is time-efficient, and it also can exploit the intrinsic manifold geometric structure and discriminant information. Consequently, it bears more discriminant ability. Experiments are carried out on face recognition, and they show the relatively promising performance of the proposed algorithm.

The analog front end circuit is an important part of the digital storage oscilloscope. This paper designs a wide band, low noise and high input impedance analog front end circuit. It includes high impedance buffer, single-ended-to-differential conversion, DC offset adjustment, variable gain amplifier and low noise power modules. We used a high-impedance passive probe with this circuit to perform a deep performance test, which contains time and frequency domain. The test results show that it can be well matched with general probe. The front end system has good performance. The bandwidth reaches about 500 MHz and the noise floor RMS voltage is 5.1 mV. The bandwidth and noise floor can meet the GSPS sampling rate and 8-bit vertical resolution digital oscilloscope requirements.

Background Coxsackievirus B3 (CVB3) is the primary cause of infectious myocarditis. Aggressive immunological activation and apoptosis of myocytes contributes to progressive dysfunction of cardiac contraction and poor prognosis. MG-132, a proteasome inhibitor, regulates mitochondrial-mediated intrinsic myocardial apoptosis and downregulates NF-κB-mediated inflammation. Here, we determined whether AMPK pathway participates in MG-132-mediated myocardial protection in viral-induced myocarditis. Methods and results Acute viral myocarditis models were established by intraperitoneal inoculation of CVB3 in male BALB/c mice. Myocarditis and age-matched control mice were administered MG-132 and/or BML-275 dihydrochloride (BML) (AMPK antagonist) intraperitoneally daily from the day following CVB3 inoculation. MG-132 improved hemodynamics and inhibited the structural remodeling of the ventricle in mice with myocarditis, while BML largely blunted these effects. TUNEL staining and immunochemistry suggested that MG-132 exerts anti-apoptotic and anti-inflammatory effects against CVB3-induced myocardial injuries. BML attenuated the effects of MG-132 on anti-apoptosis and anti-inflammation. Conclusion MG-132 modulated apoptosis and inflammation, improved hemodynamics, and inhibited the structural remodeling of ventricles in a myocarditis mouse model via regulation of the AMPK signal pathway.

The strap-on launch vehicle is widely adopted in order to increase the launching capability of the launch vehicle, especially in the unmanned system. The connect and separation equipment between the core and the booster is one of the most key techniques in the aerospace unmanned system. In this paper, the mechanical property of the astronautic separation equipment is researched based on the different axial stiffness in tension and compression characteristics, which could be simulated as the bi-linear spring model. With the single degree of freedom analytical schematic model, every design parameter that affects the separation equipment's stiffness is researched, which can optimize the astronautic separation equipment's mechanical property. This method can provide a reference and a basis for the aerospace unmanned system design.

In order to analyze the transient characteristic of voltage dividers in HVDC systems, the transfer function of DC voltage divider is derived. Analysis results show that the characteristics of DC voltage divider are determined by both two-stage resistor-capacitor voltage bleeder circuit and isolation amplifier circuit. Especially, if the parameters of the resistors and capacitors in two-stage bleeder circuits are all match well, cutoff frequency of the isolation amplifier will become the most key parameter, which determines the transmission characteristics of divider. When the cutoff frequency of isolation amplifier decreases, the rise time of the step response of DC voltage divider increases significantly. Furthermore, the effects of the transient characteristics of DC voltage divider on undervoltage sensing protection are also analyzed by simulation. Simulation results indicate that the fault component of the voltage at the secondary side of divider is much smaller than that in the first side, when the short fault occurs. Therefore, the sensitivity and the anti-resistant capacity of the protection are also decreased. Increasing the cut-off frequency may be an effective way to increase the sensitivity of such protection.

Applying atmospheric plasma etching to the surface texturing process of silicon solar cells is a promising strategy for the current photovoltaic manufacturing industry due to its low equipment cost and good fabrication flexibility. This paper investigates the morphology evolution of the silicon surface etched by an Ar/CF4/O2 plasma and the associated optical properties. Results show that the generation of the light trapping structure on the polished silicon surface can be divided into two stages on the basis of the multi-scale morphological images and the quantitative evaluation of roughness parameters. The initial roughening stage mainly involves the formation of high-frequency nanoroughness that can act as an effective medium layer with a gradual refractive index. The resulting optical medium effect can reduce the surface reflectance within a broad range of wavelengths. At the next texturing stage, the low-frequency and high-amplitude microroughness dominates the morphology of the etched silicon surface. It features inverted parabolic structures with a high aspect ratio, which can cause multiple reflections of the incident light. The optical medium effect resulting from the nanoroughness is also inherited. Thus, the anti-reflectance property of the etched silicon surface is greatly improved. This work demonstrates that the light trapping properties of silicon surface etched by atmospheric plasma jet are a synergy of the optical medium effect and geometrical optics. Insights into the morphology evolution and optical properties of the textured surfaces are important for developing a new surface texturing process of silicon solar cells.

The accurate estimation of the state of power (SoP) in battery systems is crucial for battery safety of hybrid electric vehicles and pure electric vehicles. Discharge or charge with large current might lead to significant rise of temperature to batteries. To improve the estimation accuracy of SoP for battery management systems, thermal characteristics of batteries during acceleration or deceleration of electric vehicles are considered. Considering the heat transfer from electrochemical reactions and joule heating to the air and consequently a corresponding rise of battery temperature, a model is established in Matlab/Simulink ® and integrated into the calculation process of SoP based on an 18650-type cylinder lithium-ion battery. The corresponding simulation results show that temperature limits have more influence than state of charge limits and terminal-voltage-based limits under high air temperature and high battery temperature. It is proven that multi-constraint SoP estimation method including the thermal effect has the potential to achieve higher prediction precision compared with the general SoP estimation methods.

This study aimed to investigate the development and bioactive compounds of biofloc promoted by adding molasses and wheat bran to zero-water exchange culture tanks and their effects on physiological parameters and growth performance of juvenile Litopenaeus vannamei (initial weight: 6.8 ± 0.4 g). Different combinations of molasses and wheat bran were added as carbon sources: T1, 100% molasses; T2, 50% molasses + 50% wheat bran; T3, 25% molasses + 75% wheat bran. Clear water tanks with water exchange served as the control group (control). After the 30-d experiment, the development of biofloc in terms of total suspended solids (TSS) and biofloc volume (BFV) showed significant differences in the three biofloc treatments, especially the highest levels of TSS and BFV observed in T3. The levels of poly-beta-hydroxybutyrate or polysaccharide in the biofloc of T1 and T2 were significantly higher than those in T3. Meanwhile, compared with the control group, most of the immune and antioxidant parameters and growth performance of shrimp were significantly enhanced in biofloc treatments, especially in T1 or T2. In conclusion, different carbon sources could effectively affect the development and bioactive compounds of biofloc, which could improve physiological health status and growth performance of shrimp in zero-water exchange systems.

A novel method of controller parameter tuning is proposed, based on the guardian maps stability theory. The tuning sequence could be divided into three steps: first, make sure the appropriate region in the complex plane in order to achieve the desired performance. Then, calculate the guardian function with guardian maps techniques. Finally, let the guardian function equal to zero, and find the parameters tuning space by solving the equation. Besides, if the controller parameters are selected, we can make sure the allowable perturbation range of the plant parameters is determined. It can be shown that our new performance-oriented scheme is convenient and practical, and also it is suitable for solving the controller parameter tuning problems of various plants with most of the classical control methods.

Large bowel perforation is an acute abdominal emergency requiring rapid diagnosis for proper treatment. The high mortality rate associated with large bowel perforation underlines the importance of an accurate and timely diagnosis. Computed tomography is useful for diagnosis of ingested foreign bodies, and endoscopic repair using clips can be an effective treatment of colon perforations. We herein describe a 78-year-old man with sigmoid colon perforation caused by accidental swallowing of a jujube pit. The jujube pit had become stuck in the wall of the sigmoid colon and was successfully removed by colonoscopy, avoiding an aggressive surgery. As a result of developments in endoscopic techniques, endoscopic closure has become a feasible option for the management of intestinal perforation.

The permanent 3D-printed concrete envelope formwork can realize the personalized printing of special-shaped envelope structures efficiently with a high degree of automation and obvious advantages. This paper calculated the load-bearing characteristics of the 3D-printed concrete envelope formwork and analyzed the influence of steel supports on its load-bearing characteristics based on PFT. The study showed that the structure would have the highest bearing capacity when the position of steel support reinforcement was near the bisected point of the structure and close to the resultant point of the external load; steel support reinforcement could increase the bearing capacity of structures by nearly 5 times; compared with the single support, the double support could increase the same by nearly 3 times; and triple support reinforcement played a limited role in the improvement of the bearing capacity of structures.

In the process of mine production, the properties of the ore is an important reference for the operation of each working procedure. In this article, a mathematical model is established to track bulk materials in the fine ore bin. For the uncertainty of the movement of materials within the fine ore bin, monte carlo method random sampling simulation is used to produces a large amount of enter and discharge sequence. According to calculation result, the properties of the discharged ore over a period of time can be calculated. Experiments show that the model has good precision, and can provide good support for the decision of mine processes.