1,072 results on '"Feng Qu"'
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2. VR Scene Detail Enhancement Method Based on Depth Reinforcement Learning Algorithm
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Changbao Feng, Xin Tong, Meili Zhu, and Feng Qu
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Deep reinforcement learning ,VR scene ,Detail enhancement ,Expose framework ,Gradient descent method ,Meta learning ,Electronic computers. Computer science ,QA75.5-76.95 - Abstract
Abstract In virtual reality, due to factors such as light sources and surface materials of objects, the details of the scene exhibit extremely complex changes, making it difficult to capture environmental modeling relationships and reducing the quality of scene details. Therefore, a VR scene detail enhancement method based on deep reinforcement learning algorithm is proposed. Using the Total Variation (TV) denoising algorithm to decompose the VR scene, the VR scene is divided into two parts: noisy and non-noisy, to complete the noise removal. Based on the denoised VR scene, a Hessian matrix is constructed to extract VR scene features using the SURF algorithm. Using deep reinforcement learning algorithms to train and process the extracted VR visual features, introducing meta-learning within the gradient descent method, updating the parameters of the deep reinforcement learning Expose framework, and accelerating the training speed of the deep reinforcement learning Expose framework. By designing L1 loss, structural similarity loss, content perception loss, and sharpness loss functions, the enhancement effect of VR visual details can be improved. The experimental results show that the proposed method enhances the gray-scale values and distribution of VR scene detail images to be higher and more uniform. When the magnification is different, the studied method can effectively enhance the signal-to-noise ratio of VR scenes. Therefore, it indicates that the VR scene detail enhancement effect of the method proposed in this article is good.
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- 2024
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3. Improved shape-from-template method with perspective space constraints for disappearing features
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Dongliang Tan, Huamin Yang, Zhengang Jiang, Weili Shi, Jun Qin, and Feng Qu
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Shape-from-Template ,Computer Vision ,Virtual Reality ,Digital Modeling ,Electronic computers. Computer science ,QA75.5-76.95 ,Information technology ,T58.5-58.64 - Abstract
Abstract Inferring the 3D surface shape of a known template from 2D images captured by a monocular camera is a challenging problem. Due to the severely underconstrained nature of the problem, inferring shape accurately becomes particularly challenging when the template exhibits high curvature, resulting in the disappearance of feature points and significant differences between the inferred and actual deformations. To address this problem, this paper proposes a concise and innovative approach that utilizes a physical simulator incorporating the object’s material properties and deformation law. We utilize a view frustum space constructed from the contours of a monocular camera image to effectively restrict the physically-based free motion of the template. Additionally, we employ mesh denoising techniques to ensure the smoothness of the surface following deformation. To evaluate our shape inference results, we utilize a ground truth 3D point cloud generated from multiple viewpoint images. The results demonstrate the superior performance of our approach compared to other methods in accurately inferring deformations, particularly in scenarios where feature points are unobservable. This method carries significant practical implications across diverse domains, including virtual reality, digital modeling, and medical surgery training.
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- 2024
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4. Study on Mechanical Performance of Tunnel Interface between 3D Printed Lining and Surrounding Rock
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Feng QU
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metro ,tunnel lining ,3d printing ,roughness ,bonding mechanical performance ,interface micro-structure ,Transportation engineering ,TA1001-1280 - Abstract
[Objective] Research on and application of 3D printing technology in engineering structure construction are gradually deepening. Applying 3D printing in tunnel construction creates a new idea and approach. In the process of 3D printing construction, ensuring the co-construction effect and collaborative working performance of tunnel lining and surrounding rock is crucial to building a tunnel lining structure system. Therefore, it is necessary to conduct in-depth research on it. [Method] Through experimental simulation of the interface characteristics under different surrounding rock conditions, the bonding mechanical performance between the lining and surrounding rock is thoroughly investigated together with the influencing factors in 3D printing tunnel construction. [Result & Conclusion] The roughness of the surrounding rock surface significantly influences the bonding effect of 3D printed concrete lining, while the surface coating can effectively improve the bonding performance of the lining-surrounding rock interface. Filling in the micro unevenness of the interface is helpful to improve the construction quality of 3D printed lining.
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- 2024
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5. Examining the joint coordination during dynamic balance learning using vector coding and statistical parametric mapping analyses
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Sungmin Kim, Feng Qu, Yi Wang, and Wing-kai Lam
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Medicine ,Science - Abstract
Abstract We aimed to examine the changes in balance performance, kinematic variables, and joint coordination of the lower extremities during the Y-balance learning task. Twenty female university students completed five consecutive blocks of Y-balance learning from days 3 to 7 (135 trials). Pre-tests and tests were performed on days 1 and 9. Maximum reach distance, peak joint angle, and joint coordination in the anterior (AL), posterolateral (PL), and posteromedial (PM) directions were measured to determine the efficacy of Y-balance performance. A repeated measures ANOVA was performed for the maximum reach distance across learning blocks to confirm whether learning had occurred. Our results indicated that the maximum reach distance on day 5 was longer than that on other learning days. The maximum reach distance significantly increased in the PL and PM directions after learning. The hip flexion (PL/PM), abduction (PM), internal rotation (PM), and external rotation (PL) angles increased after learning. The knee joint flexion angle increased in both AL and PL directions. Only the ankle dorsiflexion angle increased in the AL direction. Joint coordination indicated that the knee and hip joints performed simultaneously during internal rotation. Ankle-knee joint coordination was performed using dorsiflexion and flexion strategies. Statistical parametric mapping analysis indicated significant differences in the ankle sagittal plane in the AL direction, hip horizontal and hip/knee sagittal planes in the PL direction, and hip/knee sagittal and hip frontal/horizontal planes in the PM direction. These data suggest that the dynamic balance ability of the novice participants improved in relation to changes in coordination patterns after learning. The results of this study can be applied to other populations to improve their dynamic balance and prevent fall injuries.
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- 2024
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6. Heel-to-toe drop effects on biomechanical and muscle synergy responses during uphill walking
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Liang Jiang, Feng Qu, Zihan Yang, Xue Chen, Xianzhi Gao, Qing Sun, and Bo Huo
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slope ,heel-to-toe drop ,gait ,joint work ,frontal plane ,muscle synergy ,Biotechnology ,TP248.13-248.65 - Abstract
Uphill walking is a common task encountered in daily life, with steeper inclines potentially imposing greater biomechanical and neuromuscular demands on the human body. The heel-to-toe drop (HTD) in footwear may influence the biomechanical and neuromuscular pattern of uphill walking; but the impact remains unclear. Adjustments in HTD can modulate biomechanical and neuromuscular patterns, mitigating the demands and optimizing the body’s response to different inclinations. We hypothesize that adjustments in HTD can modulate biomechanical and neuromuscular patterns, mitigating the demands and optimizing the body’s response to different inclinations. Nineteen healthy men walked on an adjustable slope walkway, with varied inclinations (6°, 12°, 20°) and HTD shoes (10mm, 25mm, 40 mm), while the marker positions, ground reaction forces and electromyography data were collected. Our study reveals that gait temporo-spatial parameters are predominantly affected by inclination over HTD. Inclination has a more pronounced effect on kinematic variables, while both inclination and HTD significantly modulate kinetic and muscle synergy parameters. This study demonstrates that an increase in the inclination leads to changes in biomechanical and neuromuscular responses during uphill walking and the adjustment of HTD can modulate these responses during uphill walking. However, the present study suggests that an increased HTD may lead to elevated loads on the knee joint and these adverse effects need more attention.
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- 2024
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7. Experimental phasing opportunities for macromolecular crystallography at very long wavelengths
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Kamel El Omari, Ramona Duman, Vitaliy Mykhaylyk, Christian M. Orr, Merlyn Latimer-Smith, Graeme Winter, Vinay Grama, Feng Qu, Kiran Bountra, Hok Sau Kwong, Maria Romano, Rosana I. Reis, Lutz Vogeley, Luca Vecchia, C. David Owen, Sina Wittmann, Max Renner, Miki Senda, Naohiro Matsugaki, Yoshiaki Kawano, Thomas A. Bowden, Isabel Moraes, Jonathan M. Grimes, Erika J. Mancini, Martin A. Walsh, Cristiane R. Guzzo, Raymond J. Owens, E. Yvonne Jones, David G. Brown, Dave I. Stuart, Konstantinos Beis, and Armin Wagner
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Chemistry ,QD1-999 - Abstract
Abstract Despite recent advances in cryo-electron microscopy and artificial intelligence-based model predictions, a significant fraction of structure determinations by macromolecular crystallography still requires experimental phasing, usually by means of single-wavelength anomalous diffraction (SAD) techniques. Most synchrotron beamlines provide highly brilliant beams of X-rays of between 0.7 and 2 Å wavelength. Use of longer wavelengths to access the absorption edges of biologically important lighter atoms such as calcium, potassium, chlorine, sulfur and phosphorus for native-SAD phasing is attractive but technically highly challenging. The long-wavelength beamline I23 at Diamond Light Source overcomes these limitations and extends the accessible wavelength range to λ = 5.9 Å. Here we report 22 macromolecular structures solved in this extended wavelength range, using anomalous scattering from a range of elements which demonstrate the routine feasibility of lighter atom phasing. We suggest that, in light of its advantages, long-wavelength crystallography is a compelling option for experimental phasing.
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- 2023
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8. CPF-UNet: A Dual-Path U-Net Structure for Semantic Segmentation of Panoramic Surround-View Images
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Qiqing Sun and Feng Qu
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semantic segmentation ,encoders ,decoders ,dual-path structures ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
In this study, we propose a dual-stream UNet neural network architecture design named CPF-UNet, specifically designed for efficient semantic pixel-level segmentation tasks. This architecture cleverly extends the basic structure of the original UNet, mainly through the addition of a unique attention-guided branch in the encoder part, aiming to enhance the model’s ability to comprehensively capture and deeply fuse contextual information. The uniqueness of CPF-UNet lies in its dual-path mechanism, which differs from the dense connectivity strategy adopted in networks such as UNet++. The dual-path structure in this study can effectively integrate deep and shallow features without relying excessively on dense connections, achieving a balanced processing of image details and overall semantic information. Experiments have shown that CPF-UNet not only slightly surpasses the segmentation accuracy of UNet++, but also significantly reduces the number of model parameters, thereby improving inference efficiency. We conducted a detailed comparative analysis, evaluating the performance of CPF-UNet against existing UNet++ and other corresponding methods on the same benchmark. The results indicate that CPF-UNet achieves a more ideal balance between accuracy and parameter quantity, two key performance indicators.
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- 2024
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9. Self-Responsive Fluorescence Aptasensor for Lactoferrin Determination in Dairy Products
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Hao Liu, Xibao Gao, Hongwei Qin, Mengmeng Yan, Chao Zhu, Linsen Li, and Feng Qu
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aptamer ,self-responsive ,fluorescence aptasensor ,lactoferrin detection ,Organic chemistry ,QD241-441 - Abstract
In this study, a self-responsive fluorescence aptasensor was established for the determination of lactoferrin (Lf) in dairy products. Herein, the aptamer itself functions as both a recognition element that specifically binds to Lf and a fluorescent signal reporter in conjunction with fluorescent moiety. In the presence of Lf, the aptamer preferentially binds to Lf due to its specific and high-affinity recognition by folding into a self-assembled and three-dimensional spatial structure. Meanwhile, its reduced spatial distance in the aptamer–Lf complex induces a FRET phenomenon based on the quenching of 6-FAM by amino acids in the Lf protein, resulting in a turn-off of the fluorescence of the system. As a result, the Lf concentration can be determined straightforwardly corresponding to the change in the self-responsive fluorescence signal. Under the optimized conditions, good linearities (R2 > 0.99) were achieved in an Lf concentration range of 2~10 μg/mL for both standard solutions and the spiked matrix, as well as with the desirable detection limits of 0.68 μg/mL and 0.46 μg/mL, respectively. Moreover, the fluorescence aptasensor exhibited reliable recoveries (89.5–104.3%) in terms of detecting Lf in three commercial samples, which is comparable to the accuracy of the HPCE method. The fluorescence aptasensor offers a user-friendly, cost-efficient, and promising sensor platform for point-of-need detection.
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- 2024
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10. The Effects of Hand Tremors on the Shooting Performance of Air Pistol Shooters with Different Skill Levels
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Yu Liu, Nijia Hu, Mengzi Sun, Feng Qu, and Xinglong Zhou
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physiological tremor ,tremor amplitude ,tremor complexity ,multiscale entropy ,muscle activation ,Chemical technology ,TP1-1185 - Abstract
Physiologic hand tremors are a critical factor affecting the aim of air pistol shooters. However, the extent of the effect of hand tremors on shooting performance is unclear. In this study, we aim to explore the relationship between hand tremors and shooting performance scores as well as investigate potential links between muscle activation and hand tremors. In this study, 17 male air pistol shooters from China’s national team and the Air Pistol Sports Center were divided into two groups: the elite group and the sub-elite group. Each participant completed 40 shots during the experiment, with shooters’ hand tremors recorded using three-axis digital accelerometers affixed to their right hands. Muscle activation was recorded using surface electromyography on the right anterior deltoid, posterior deltoid, biceps brachii (short head), triceps brachii (long head), flexor carpi radialis, and extensor carpi radialis. Our analysis revealed weak correlations between shooting scores and hand tremor amplitude in multiple directions (middle-lateral, ML: r2 = −0.22, p < 0.001; vertical, VT: r2 = −0.25, p < 0.001), as well as between shooting scores and hand tremor complexity (ML: r2 = −0.26, p < 0.001; VT: r2 = −0.28, p < 0.001), across all participants. Notably, weak correlations between shooting scores and hand tremor amplitude (ML: r2 = −0.27, p < 0.001; VT: r2 = −0.33, p < 0.001) and complexity (ML: r2 = −0.31, p < 0.001) were observed in the elite group but not in the sub-elite group. Moderate correlation were found between the biceps brachii (short head) RMS and hand tremor amplitude in the VT and ML directions (ML: r2 = 0.49, p = 0.010; VT: r2 = 0.44, p = 0.025) in all shooters, with a moderate correlation in the ML direction in elite shooters (ML: r2 = 0.49, p = 0.034). Our results suggest that hand tremors in air pistol shooters are associated with the skill of the shooters, and muscle activation of the biceps brachii (long head) might be a factor affecting hand tremors. By balancing the agonist and antagonist muscles of the shoulder joint, shooters might potentially reduce hand tremors and improve their shooting scores.
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- 2024
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11. The Double Identities of the Shaman and the Dualistic Attitudes of the State: An Exploration of Contemporary Organizational Shamanism in Northeast China
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Feng Qu
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organizational shamanism ,double identities ,heritagization process ,dualistic attitudes ,superstitious ,Religions. Mythology. Rationalism ,BL1-2790 - Abstract
This paper presents a case study of the first shamanic organization in China and argues that organizational shamanism in Northeast China is characterized by the double identities of the shaman and the dualistic attitudes of the national authorities. The analyses in this paper reveal how the shamanic organization created a modernized and globalized space for traditional shamans and specialists to connect with the outside world, enabling them to gain empowerment, legitimacy, and agency. Chinese authorities hold dualistic attitudes towards shamanism: the positive attitude of seeing shamanism as part of cultural heritage has always been coupled with the negative attitude of seeing shamanism as superstition. The studies in this paper demonstrate that organizational shamanism in Northeast China has played a crucial role in negotiating with political authorities and linking local traditions with global discourse. In this sense, the traditional eco-cosmological way of maintaining relationships with natural forces and nonhuman beings has been irrevocably transformed into a cosmopolitical form for the shaman, where the animistic world engages with the outside world, global currency, and political forces.
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- 2024
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12. COVID19-ResCapsNet: A Novel Residual Capsule Network for COVID-19 Detection From Chest X-Ray Scans Images
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Zhihua Li, Qiwei Xing, Jiashi Zhao, Yu Miao, Ke Zhang, Guanyuan Feng, Feng Qu, Yanfang Li, Wei He, Weili Shi, and Zhengang Jiang
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COVID-19 detection ,residual network ,capsule network ,deep learning ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 - Abstract
In the global outbreak of corona-virus disease (COVID-19), it is of foremost priority to find an efficient and faster diagnosis method to reduce the transmission rate of the COVID-19 disease. Recently, deep learning-based detection methods have been proposed as a potential diagnostic tool, because there is much essential information in the radio-logical images for COVID-19 detection. This paper intends to develop a hybrid deep neural network (COVID19-ResCapsNet), using the X-ray images, to predict the risk at the onset of disease in patients suffering from COVID-19. The proposed COVID19-ResCapsNet method consists of two steps. The first step is mainly to extract features with the improved Residual feature extraction network. In the final step, several Capsule Networks are employed to classify COVID-19, and Non COVID-19. The proposed method is evaluated on two CXR image datasets(Dataset-1: 4236 images and Dataset-2: 2250 images) and the classification accuracy can reach 0.9988 on Dataset-1 and 0.9933 on Dataset-2 for binary classification cases. The results are compared with several state-of-the-art pre-trained classification models. The effects of two important hyper parameters: different optimizer and batch size, have also been investigated. Hence, the proposed COVID-19 detection model is effective and can be used as the supplementary tool in clinical application.
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- 2023
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13. A case report: extracorporeal membrane oxygenation for multitrauma patient with pneumorrhagia
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Qiang Meng, Changwei Ji, Zhen Ma, Bo wang Chen, Hao Zhang, Jun Li, Lin Cong, Feng Qu, and Shuhong Gao
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Case report ,Multitrauma ,Acute respiratory distress syndrome ,Extracorporeal membrane oxygenation ,D-dimer ,Diseases of the respiratory system ,RC705-779 ,Medical emergencies. Critical care. Intensive care. First aid ,RC86-88.9 - Abstract
Abstract Background Extracorporeal membrane oxygenation (ECMO) can be used as salvage therapy for multitrauma patients with acute respiratory distress syndrome (ARDS) when conventional treatment fails to maintain oxygenation. However, controversy exists between ECMO application and the risk of bleeding due to systemic anticoagulation during the treatment. Non-heparin introduction seems to be a possible solution for this dilemma, owing to technical improvements in the device and management methods of ECMO. Case presentation A 58-year-old woman suffered from blunt thoracic, pelvic, and right lower limb fractures due to a falling accident, which resulted in acute respiratory distress syndrome (ARDS). Although the patient received intubation and mechanical ventilation (MV), respiratory failure was not alleviated. Venous-venous (V-V) ECMO was used as a salvage therapy. With the support of V-V ECMO, we safely cleared blood clots in the bronchus and avoided secondary lung injury caused by pressure trauma and oxygen poisoning of the MV. We introduced heparin-free ECMO management as a solution to reduce the risk of bleeding associated with pulmonary contusion and other organ injuries. To prevent thrombosis, we set the blood rate of ECMO to 4.0 L/min, which is much higher than the usual parameter. During ECMO, coagulation factors, such as prothrombin time, activated partial thromboplastin time, and D-dimer, were examined. ECMO was maintained for 5 days without any complications; MV was stopped on the 13th day, extubated on the 24th day, and discharged from ICU on the 28th day. Conclusion ECMO with non-heparin could be an optimal treatment for multitrauma patients with ARDS when traditional treatment cannot sustain oxygenation. High blood flow rate could prevent thrombosis through ongoing ECMO therapy without systemic anticoagulation. In addition, monitoring D-dimer value change (Δ D-dimer) may be better than D-dimer value in predicting clot formation in the membrane oxygenator.
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- 2023
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14. FTL004, an anti-CD38 mAb with negligible RBC binding and enhanced pro-apoptotic activity, is a novel candidate for treatments of multiple myeloma and non-Hodgkin lymphoma
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Guangbing Zhang, Cuiyu Guo, Yan Wang, Xianda Zhang, Shuang Liu, Wen Qu, Chunxia Chen, Lingli Yan, Zhouning Yang, Zhixiong Zhang, Xiaohua Jiang, Xiaofeng Chen, Hong Liu, Qinhuai Lai, Xian Wei, Ying Lu, Shengyan Zhao, Han Deng, Yuxi Wang, Lin Yu, Hongbin Yu, Yu Wu, Zhaoming Su, Pengyu Chen, Ziqing Ren, Meng Yu, Feng Qu, Yong Luo, Lantu Gou, Qing Li, Ying Huang, Fanxin Ma, and Jinliang Yang
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Multiple myeloma ,Monoclonal antibodies ,CD38 ,Red blood cells ,Direct apoptosis ,Diseases of the blood and blood-forming organs ,RC633-647.5 ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Abstract Anti-CD38 monoclonal antibodies (mAbs), daratumumab, and isatuximab have represented a breakthrough in the treatment of multiple myeloma (MM). Recently, CD38-based mAbs were expected to achieve increasing potential beyond MM, which encouraged us to develop new anti-CD38 mAbs to meet clinical needs. In this study, we developed a novel humanized anti-CD38 antibody, FTL004, which exhibited enhanced pro-apoptotic ability and negligible binding to red blood cells (RBCs). FTL004 presented a better ability to induce direct apoptosis independent of Fc-mediated cross-linking against lymphoma and MM cell lines as well as primary myeloma cells derived from MM patients. For instance, FTL004 induced RPMI 8226 cells with 55% early apoptosis cells compared with 20% in the isatuximab-treated group. Of interest, FTL004 showed ignorable binding to CD38 on human RBCs in contrast to tumor cells, even at concentrations up to 30 μg/mL. Furthermore, with an engineered Fc domain, FTL004 displayed stronger antibody-dependent cellular cytotoxicity (ADCC) against CD38+ malignant cells. In vivo MM and non-Hodgkin lymphoma tumor xenograft models showed that FTL004 possessed an effective anti-tumor effect. Cryo-electron microscopy structure resolved two epitope centers of FTL004 on CD38: one of which was unique while the other partly overlapped with that of isatuximab. Taken together, FTL004 distinguishes it from other CD38 targeting mAbs and represents a potential candidate for the treatment of MM and non-Hodgkin lymphoma.
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- 2022
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15. Musculoskeletal simulation of professional ski jumpers during take-off considering aerodynamic forces
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Yi Huang, Liang Jiang, Xue Chen, Qing Sun, Xiao Zhang, Xunan Tan, Yan Du, Fangtong Zhang, Nannan Wang, Rufeng Su, Feng Qu, Guoqing Zhang, and Bo Huo
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ski jumping ,take-off ,musculoskeletal simulation ,aerodynamics ,muscle activation ,joint torque ,Biotechnology ,TP248.13-248.65 - Abstract
Introduction: Musculoskeletal simulation has been widely used to analyze athletes’ movements in various competitive sports, but never in ski jumping. Aerodynamic forces during ski jumping take-off have been difficult to account for in dynamic simulation. The purpose of this study was to establish an efficient approach of musculoskeletal simulation of ski jumping take-off considering aerodynamic forces and to analyze the muscle function and activity.Methods: Camera-based marker-less motion capture was implemented to measure the take-off kinematics of eight professional jumpers. A suitable full-body musculoskeletal model was constructed for the simulation. A method based on inverse dynamics iteration was developed and validated to estimate the take-off ground reaction force. The aerodynamic forces, which were calculated based on body kinematics and computational fluid dynamics simulations, were exerted on the musculoskeletal model as external forces. The activation and joint torque contributions of lower extremity muscles were calculated through static optimization.Results: The estimated take-off ground reaction forces show similar trend with the results from past studies. Although overall inconsistencies between simulated muscle activation and EMG from previous studies were observed, it is worth noting that the activation of the tibialis anterior, gluteus maximus, and long head of the biceps femoris was similar to specific EMG results. Among lower extremity extensors, soleus, vastus lateralis, biceps femoris long head, gluteus maximus, and semimembranosus showed high levels of activation and joint extension torque contribution.Discussion: Results of this study advanced the understanding of muscle action during ski jumping take-off. The simulation approach we developed may help guide the physical training of jumpers for improved take-off performance and can also be extended to other phases of ski jumping.
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- 2023
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16. Single-cell mutation rate of turnip crinkle virus (-)-strand replication intermediates.
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Camila Perdoncini Carvalho, Junping Han, Khwannarin Khemsom, Ruifan Ren, Luis Eduardo Aranha Camargo, Shuhei Miyashita, and Feng Qu
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Immunologic diseases. Allergy ,RC581-607 ,Biology (General) ,QH301-705.5 - Abstract
Viruses with single-stranded, positive-sense (+) RNA genomes incur high numbers of errors during replication, thereby creating diversified genome populations from which new, better adapted viral variants can emerge. However, a definitive error rate is known for a relatively few (+) RNA plant viruses, due to challenges to account for perturbations caused by natural selection and/or experimental set-ups. To address these challenges, we developed a new approach that exclusively profiled errors in the (-)-strand replication intermediates of turnip crinkle virus (TCV), in singly infected cells. A series of controls and safeguards were devised to ensure errors inherent to the experimental process were accounted for. This approach permitted the estimation of a TCV error rate of 8.47 X 10-5 substitution per nucleotide site per cell infection. Importantly, the characteristic error distribution pattern among the 50 copies of 2,363-base-pair cDNA fragments predicted that nearly all TCV (-) strands were products of one replication cycle per cell. Furthermore, some of the errors probably elevated error frequencies by lowering the fidelity of TCV RNA-dependent RNA polymerase, and/or permitting occasional re-replication of progeny genomes. In summary, by profiling errors in TCV (-)-strand intermediates incurred during replication in single cells, this study provided strong support for a stamping machine mode of replication employed by a (+) RNA virus.
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- 2023
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17. A cowpea severe mosaic virus-based vector simplifies virus-induced gene silencing and foreign protein expression in soybean
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Fides Angeli Zaulda, Seung Hyun Yang, Junping Han, Sizolwenkosi Mlotshwa, Anne Dorrance, and Feng Qu
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Cowpea severe mosaic virus ,VIGS ,Expression vector ,Soybean functional genomics ,Plant culture ,SB1-1110 ,Biology (General) ,QH301-705.5 - Abstract
Abstract Background Soybean gene functions cannot be easily interrogated through transgenic disruption (knock-out) of genes-of-interest, or transgenic overexpression of proteins-of-interest, because soybean transformation is time-consuming and technically challenging. An attractive alternative is to administer transient gene silencing or overexpression with a plant virus-based vector. However, existing virus-induced gene silencing (VIGS) and/or overexpression vectors suitable for soybean have various drawbacks that hinder their widespread adoption. Results We describe the development of a new vector based on cowpea severe mosaic virus (CPSMV), a plus-strand RNA virus with its genome divided into two RNA segments, RNA1 and RNA2. This vector, designated FZ, incorporates a cloning site in the RNA2 cDNA, permitting insertion of nonviral sequences. When paired with an optimized RNA1 construct, FZ readily infects both Nicotiana benthamiana and soybean. As a result, FZ constructs destined for soybean can be first delivered to N. benthamiana in order to propagate the modified viruses to high titers. FZ-based silencing constructs induced robust silencing of phytoene desaturase genes in N. benthamiana, multiple soybean accessions, and cowpea. Meanwhile, FZ supported systemic expression of fluorescent proteins mNeonGreen and mCherry in N. benthamiana and soybean. Finally, FZ-mediated expression of the Arabidopsis transcription factor MYB75 caused N. benthamiana to bear brown leaves and purple, twisted flowers, indicating that MYB75 retained the function of activating anthocyanin synthesis pathways in a different plant. Conclusions The new CPSMV-derived FZ vector provides a convenient and versatile soybean functional genomics tool that is expected to accelerate the characterization of soybean genes controlling crucial productivity traits.
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- 2022
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18. Intracellular bottlenecking permits no more than three tomato yellow leaf curl virus genomes to initiate replication in a single cell.
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Ruifan Ren, Limin Zheng, Junping Han, Camila Perdoncini Carvalho, Shuhei Miyashita, Deyong Zhang, and Feng Qu
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Immunologic diseases. Allergy ,RC581-607 ,Biology (General) ,QH301-705.5 - Abstract
Viruses are constantly subject to natural selection to enrich beneficial mutations and weed out deleterious ones. However, it remains unresolved as to how the phenotypic gains or losses brought about by these mutations cause the viral genomes carrying the very mutations to become more or less numerous. Previous investigations by us and others suggest that viruses with plus strand (+) RNA genomes may compel such selection by bottlenecking the replicating genome copies in each cell to low single digits. Nevertheless, it is unclear if similarly stringent reproductive bottlenecks also occur in cells invaded by DNA viruses. Here we investigated whether tomato yellow leaf curl virus (TYLCV), a small virus with a single-stranded DNA genome, underwent population bottlenecking in cells of its host plants. We engineered a TYLCV genome to produce two replicons that express green fluorescent protein and mCherry, respectively, in a replication-dependent manner. We found that among the cells entered by both replicons, less than 65% replicated both, whereas at least 35% replicated either of them alone. Further probability computation concluded that replication in an average cell was unlikely to have been initiated with more than three replicon genome copies. Furthermore, sequential inoculations unveiled strong mutual exclusions of these two replicons at the intracellular level. In conclusion, the intracellular population of the small DNA virus TYLCV is actively bottlenecked, and such bottlenecking may be a virus-encoded, evolutionarily conserved trait that assures timely selection of new mutations emerging through error-prone replication.
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- 2023
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19. The effect of loss of foot sole sensitivity on H-reflex of triceps surae muscles and functional gait
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Fangtong Zhang, Mengzi Sun, Feng Qu, Kelsey Lewis, Jung Hun Choi, Qipeng Song, and Li Li
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foot sole sensitivity ,H-reflex ,functional gait ,motor control ,triceps surae muscles ,Physiology ,QP1-981 - Abstract
Objective: To investigate the effects of foot sole insensitivity on the outcomes of the triceps surae muscle H-reflex and functional gait.Material and Methods: People with peripheral neuropathy were recruited and divided into two groups: people with more (n = 13, 73.3 ± 4.3 years old) or less (n = 10, 73.5 ± 5.3) sensitive tactile sensation. Their monofilament testing scores were 9.0 ± 1.5 (range: 7–10) and 2.3 ± 2.4 (range: 0–6) out of 10, respectively. H-reflex of the triceps surae muscles during quiet standing and their relationship with functional gait, 6 min walking distance (6MWD), and timed-up-and-go duration (TUG), were compared between groups.Results: No significant difference was detected for H-reflex parameters between the groups. The less sensitive group showed reduced (p < .05) functional gait capacity compared to the other group, 38.4 ± 52.7 vs. 463.5 ± 47.6 m for 6MWD, and 9.0 ± 1.5 vs. 7.2 ± 1.1s for TUG, respectively. A significant correlation (p < .05), worse functional gait related to greater H/M ratio, was observed in the less sensitive group, not the other group.Conclusion: Although there was no significant H-reflex difference between the groups, more pronounced tactile sensation degeneration affected functional gaits and their relationship with H-reflex.
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- 2023
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20. Bacillus methylotrophicus Could Improve the Tolerance and Recovery Ability of the Tomato to Low-Temperature Stress and Improve Fruit Quality
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Guobin Li, Tieli Peng, Feng Qu, Junzheng Wang, Yanghao Long, and Xiaohui Hu
- Subjects
tomato ,low temperature ,Bacillus methylotrophicus ,growth ,fruit quality ,Agriculture - Abstract
Low-temperature stress seriously affects the growth, development, yield, and quality of tomato production. Bacillus methylotrophicus is an important plant growth promoting rhizobacteria (PGPR). However, the role of B. methylotrophicus under low-temperature stress is poorly understood. Accordingly, the effects of B. methylotrophicus (‘VL-10′) on tomato cold stress (15 °C/8 °C, 12 h/12 h, and day/night) were studied. B. methyltrophicus ‘VL-10′ was added into the substrate at the time of sowing, and the plants were treated at a low temperature for 2 weeks after 40 days of growth. We found that the low temperature reduced the spatial distribution of the aboveground and underground sections of tomatoes and the leaf SPAD and photochemical efficiency of PS II (Fv/Fm). After low-temperature stress, the tomato flowering was delayed, the vitamin C and lycopene content in fruit decreased, and the nitrate content increased. However, inoculated with B. methyltrophicus ‘VL-10′ during sowing promoted the growth of tomato seedlings, enhanced the native defense ability of the tomatoes, and effectively reduced the cold shock response of the roots to cold damage and the adverse effects of low temperature on leaf SPAD and Fv/Fm. After the cultivation at normal temperature, the inoculat B. methyltrophicus ‘VL-10′ could rapidly regain plant growth levers, and eliminate the delay of low temperature on flowering. TOPSIS analysis showed that the nutritional quality of tomatoes could be effectively improved by inoculation with B. methyltrophicus ‘VL-10′ regardless of normal cultivation or low-temperature stress.
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- 2023
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21. P3 and NIa-Pro of Turnip Mosaic Virus Are Independent Elicitors of Superinfection Exclusion
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Haritha Nunna, Feng Qu, and Satyanarayana Tatineni
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Turnip mosaic virus ,cross protection ,superinfection exclusion ,potyvirus ,P3 ,NIa-Pro ,Microbiology ,QR1-502 - Abstract
Superinfection exclusion (SIE) is an antagonistic interaction between identical or closely related viruses in host cells. Previous studies by us and others led to the hypothesis that SIE was elicited by one or more proteins encoded in the genomes of primary viruses. Here, we tested this hypothesis using Turnip mosaic virus (TuMV), a member of the genus Potyvirus of the family Potyviridae, with significant economic consequences. To this end, individual TuMV-encoded proteins were transiently expressed in the cells of Nicotiana benthamiana leaves, followed by challenging them with a modified TuMV expressing the green fluorescent protein (TuMV-GFP). Three days after TuMV-GFP delivery, these cells were examined for the replication-dependent expression of GFP. Cells expressing TuMV P1, HC-Pro, 6K1, CI, 6K2, NIa-VPg, NIb, or CP proteins permitted an efficient expression of GFP, suggesting that these proteins failed to block the replication of a superinfecting TuMV-GFP. By contrast, N. benthamiana cells expressing TuMV P3 or NIa-Pro did not express visible GFP fluorescence, suggesting that both of them could elicit potent SIE against TuMV-GFP. The SIE elicitor activity of P3 and NIa-Pro was further confirmed by their heterologous expression from a different potyvirus, potato virus A (PVA). Plants systemically infected with PVA variants expressing TuMV P3 or NIa-Pro blocked subsequent infection by TuMV-GFP. A +1-frameshift mutation in P3 and NIa-Pro cistrons facilitated superinfection by TuMV-GFP, suggesting that the P3 and NIa-Pro proteins, but not the RNA, are involved in SIE activity. Additionally, deletion mutagenesis identified P3 amino acids 3 to 200 of 352 and NIa-Pro amino acids 3 to 40 and 181 to 242 of 242 as essential for SIE elicitation. Collectively, our study demonstrates that TuMV encodes two spatially separated proteins that act independently to exert SIE on superinfecting TuMV. These results lay the foundation for further mechanistic interrogations of SIE in this virus.
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- 2023
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22. Efficient Removal of Chromium(VI) Using a Novel Waste Biomass Chestnut Shell-Based Carbon Electrode by Electrosorption
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Xiaofei Zhang, Bo Ren, Xiaonan Wu, Xin Yan, Yu Sun, Hongcheng Gao, and Feng Qu
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Chemistry ,QD1-999 - Published
- 2021
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23. Repairing sciatic nerve injury with self-assembling peptide nanofiber scaffold-containing chitosan conduit
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Xuezhen Shen, Feng Qu, Yilun Pei, Simeng Lei, Suhang Xia, Jing Liang, Shan Li, Xun Sun, and Liang Liu
- Subjects
peripheral nerve defects ,nerve regeneration ,nerve guidance conduits ,combined therapy ,self-assembling peptide ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
BackgroundAn increasing number of nerve guide scaffolds have been used to replace the “gold-standard” autologous nerve graft for repairing peripheral nerve defects, but nerve regeneration is usually far from complete.MethodsHere, we designed and prepared two functionalized self-assembling peptides (SAP) with the IKVAV and KLT sequences, which were derived from the combination of laminin and VEGF, respectively. Their mixtures were also obtained to combine the effects of neuroprotective and neurotrophic and proangiogenic factors.ResultsThe beneficial effect of peptide gels on nerve regeneration was evaluated in vitro using Schwann cells (SCs). As a useful intraluminal filling, a three-dimensional (3D) functionalized self-assembling peptide (SAP) nanofiber hydrogel was formed in the hollow lumen of chitosan conduits under physiological conditions. In vivo, the combination of the two functionalized SAP gels containing a chitosan nerve conduit significantly accelerated nerve healing and enhanced morphological repair.ConclusionBased on the current findings, the combined application of two functionalized SAP gels with chitosan nerve conduit is a promising therapy for the engineering of peripheral nerve regeneration.
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- 2022
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24. Design feature combinations effects of running shoe on plantar pressure during heel landing: A finite element analysis with Taguchi optimization approach
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Zihan Yang, Chuyi Cui, Xianglin Wan, Zhiyi Zheng, Songhua Yan, Hui Liu, Feng Qu, and Kuan Zhang
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rearfoot strike ,shoe design ,plantar pressure ,finite element method ,Taguchi method ,Biotechnology ,TP248.13-248.65 - Abstract
Large and repeated impacts on the heel during running are among the primary reasons behind runners’ injuries. Reducing plantar pressure can be conducive to reducing running injury and improving running performance and is primarily achieved by modifying the design parameters of running shoes. This study examines the effect of design parameters of running shoes (i.e., heel-cup, insole material, midsole material, and insole thickness) on landing peak plantar pressure and determines the combination of different parameters that optimize cushion effects by employing the Taguchi method. We developed the foot–shoe finite element (FE) model through reverse engineering. Model assembly with different design parameters was generated in accordance with the Taguchi method orthogonal table. The effectiveness of the model was verified using the static standing model in Ansys. The significance and contribution of different design parameters, and the optimal design to reduce plantar pressure during landing, were determined using the Taguchi method. In the descending order of percentage contribution was a conforming heel-cup (53.18%), insole material (25.89%), midsole material (7.81%), and insole thickness (2.69%). The more conforming heel-cup (p < 0.001) and softer insole (p = 0.001) reduced the heel pressure during landing impact. The optimal design of running shoe in this study was achieved with a latex insole, a 6 mm insole thickness, an Asker C-45 hardness midsole, and a 100% conforming heel-cup. The conforming heel-cup and the insole material significantly affected the peak plantar pressure during heel landing. The implementation of a custom conforming heel-cup is imperative for relieving high plantar pressure for long-distance heel-strike runners.
- Published
- 2022
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25. Self-assembly and label-free fluorescent aptasensor based on deoxyribonucleic acid intercalated dyes for detecting lactoferrin in milk powder
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Jiahui Liu, Tengfei Li, Hongwei Qin, Linsen Li, Mengmeng Yan, Chao Zhu, Feng Qu, and A. M. Abd El-Aty
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aptamer ,fluorescent aptasensor ,DNA intercalated dyes ,lactoferrin detection ,milk powder ,Nutrition. Foods and food supply ,TX341-641 - Abstract
Lactoferrin (Lf), an iron-binding glycoprotein, regulates the immune system. It has broad-spectrum antimicrobial activity and is critical for child physical growth and development. As a common additive in the dairy industry, it is crucial to quantify LF content. This study established a self-assembly and universal fluorescence aptasensor for detecting LF in milk powder based on structure-selective dyes of PicoGreen intercalated in the label-free aptamer. Herein, the aptamer functions as both a specific recognition element against targets and a fluorescent signal reporter integrated with structure-selective dyes. First, the aptamer folds into a three-dimensional spatial structure based on complementary base pairings and intermolecular weak non-covalent interactions. Then, the dye is intercalated into the minor groove structures of the aptamer and triggers its potential fluorescent property. When the target exists, the aptamer binds to it preferentially, and its space structure unfolds. This causes the freeing of the subsequent dye and decreases the corresponding fluorescence. Hence, the reflected fluorescence signals could directly determine the target concentrations. Under the optimum conditions, a good linear relationship (R2, 0.980) was obtained in the Lf range from 20 to 500 nM with a detection limit of 3 nM (2.4 mg/kg) and good specificity, as well as a reliable recovery of 95.8–105.1% in milk powder. In addition, the universality was also confirmed with a good performance by quickly changing the aptamers against other targets (chlorpyrifos, acetamiprid, bovine thyroglobulin, and human transferrin) or utilizing another fluorescence dye. Therefore, this self-assembly aptasensor provides a universal and concise strategy for effective detection.
- Published
- 2022
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26. Identification of SARS-CoV-2-against aptamer with high neutralization activity by blocking the RBD domain of spike protein 1
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Ge Yang, Ziyue Li, Irfan Mohammed, Liping Zhao, Wei Wei, Haihua Xiao, Weisheng Guo, Yongxiang Zhao, Feng Qu, and Yuanyu Huang
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Medicine ,Biology (General) ,QH301-705.5 - Published
- 2021
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27. The Reduced Adaptability of H-Reflex Parameters to Postural Change With Deficiency of Foot Plantar Sensitivity
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Mengzi Sun, Kelsey Lewis, Jung Hun Choi, Fangtong Zhang, Feng Qu, and Li Li
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H-reflex ,peripheral neuropathy ,prone ,standing ,heel-contact ,Physiology ,QP1-981 - Abstract
Purpose: The project was to examine the influence of peripheral neuropathy (PN) severity on the relationship between Hoffmann-reflex (H-reflex) and postures.Methods: A total of 34 participants were recruited. H-reflex (H/M ratio and H-index) during prone, standing, and the heel-contact phase of walking was tested, along with foot sole sensitivity.Results: The participants were divided into three groups based on the severity of the foot sole sensitivity deficit: control, less (LA), and more (MA) affected with both feet 5.07 monofilament test scores ranging 10, 0–5, and 6–9, respectively. A significant group by the posture interaction was observed in the H/M ratio (F3.0, 41.9 = 2.904, p = 0.046, ηp2 = 0.172). In the control group, the H/M ratio of prone (22 ± 7%) was greater than that of the standing (13 ± 3%, p = 0.013) and heel-contact phase (10 ± 2%, p = 0.004). In the MA group, the H/M ratio of standing (13 ± 3%) was greater than that of the heel-contact phase (8 ± 2%, p = 0.011). The H-index was significantly different among groups (F2,28 = 5.711, p = 0.008, and ηp2= 0.290). Post hoc analysis showed that the H-index of the control group (80.6 ± 11.3) was greater than that of the LA (69.8 ± 12.1, p = 0.021) and MA groups (62.0 ± 10.6, p = 0.003).Conclusion: In a non-PN population, the plantar sensory input plays an important role in maintaining standing postural control, while as for the PN population with foot sole sensitivity deficiency, type Ⅰ afferent fibers reflex loop (H-reflex) contributes more to the standing postural control. The H-index parameter is an excellent method to recognize the people with and without PN but not to distinguish the severity of PN with impaired foot sole sensitivity.
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- 2022
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28. Screening and Identification of ssDNA Aptamers for Low-Density Lipoprotein (LDL) Receptor-Related Protein 6
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Xiaomin Zhang, Ge Yang, Wenjing Liu, Qing Liu, Zhuoran Wang, Kelong Fan, Feng Qu, and Yuanyu Huang
- Subjects
LRP6 ,aptamer ,capillary electrophoresis ,SELEX ,Organic chemistry ,QD241-441 - Abstract
Low-density lipoprotein receptor-related protein 6 (LRP6), a member of the low-density lipoprotein receptor (LDLR) family, displays a unique structure and ligand-binding function. As a co-receptor of the Wnt/β-catenin signaling pathway, LRP6 is a novel therapeutic target that plays an important role in the regulation of cardiovascular disease, lipid metabolism, tumorigenesis, and some classical signals. By using capillary electrophoresis–systematic evolution of ligands by exponential enrichment (CE-SELEX), with recombinant human LRP-6 as the target, four candidate aptamers with a stem-loop structure were selected from an ssDNA library—AptLRP6-A1, AptLRP6-A2, AptLRP6-A3, and AptLRP6-A4. The equilibrium dissociation constant KD values between these aptamers and the LRP6 protein were in the range of 0.105 to 1.279 μmol/L, as determined by CE-LIF analysis. Their affinities and specificities were further determined by the gold nanoparticle (AuNP) colorimetric method. Among them, AptLRP6-A3 showed the highest affinity with LRP6-overexpressed human breast cancer cells. Therefore, the LRP6 aptamer identified in this study constitutes a promising modality for the rapid diagnosis and treatment of LRP6-related diseases.
- Published
- 2023
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29. Deconstruction of the Trance Model: Historical, Ethnographic, and Contextual Studies of Manchu Shamanism
- Author
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Feng Qu
- Subjects
trance model ,Manchu ,court shamanism ,clan shamanism ,wild shamanism ,Religions. Mythology. Rationalism ,BL1-2790 - Abstract
Social trends and historical contexts have popularized Eliade’s trance model in shamanism studies and have contributed to a famous academic debate. A case study on Manchu shamanism conducted in this article shows that a Manchu shaman functions primarily as a sacrificial specialist rather than a mental state adept. Three types of Manchu shamanism—court shamanism, clan shamanism, and wild shamanism—are examined based on historical and ethnographic analyses. This study deconstructs the trance model and demonstrates that shamanism among Manchus has a dynamic, reactive, constitutive, and unstable historical process.
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- 2023
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30. Effect of Wet-Dry Cycles on the Mechanical Performances and Microstructure of Pisha Sandstone
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Yanbing Zhao, Caiqian Yang, Feng Qu, Zhiren Wu, Kejie Ding, and Zhishui Liang
- Subjects
Pisha sandstone ,microstructure ,mineral compositions ,uniaxial compressive strength ,wet–dry cycles ,Organic chemistry ,QD241-441 - Abstract
The effects of the wet–dry cycles on the chemical compositions, microstructure, and mechanical properties of Pisha sandstone were experimentally investigated in the current study. A series of uniaxial compression tests were conducted to validate the deterioration of the mechanical property of specimens after wet–dry cycles. In addition, the evolutions of the mineral compositions and microstructure characteristics were confirmed by X-ray diffraction (XRD) and scanning electron microscope (SEM). Experimental results indicated that with the increase of wet–dry cycles, the mechanical properties of Pisha sandstone gradually decrease. After five wet–dry cycles, the uniaxial compressive strength, elastic modulus, and fracture energy of specimens were reduced by 41.06%, 62.39%, and 31.92%, respectively. The failure mode of the specimen changes from inclined shear failure to peel failure. Compared to the initial specimens, the relative content of primary minerals after five wet–dry cycles declined by 5.94%, and the relative content of clay minerals after five wet–dry cycles increased by 54.33%. Additionally, the porosity of samples exhibits a positive correlation with wet–dry cycles. Compared to the initial specimens, the porosity of specimens after five wet–dry cycles increased by 176.32%. Finally, a prediction model of the correlation between uniaxial compressive strength and porosity is proposed and verified.
- Published
- 2023
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31. LncRNA HOXA-AS3 promotes gastric cancer progression by regulating miR-29a-3p/LTβR and activating NF-κB signaling
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Feng Qu, Bin Zhu, Yi-Lin Hu, Qin-Sheng Mao, and Ying Feng
- Subjects
HOXA-AS3 ,Gastric cancer ,miR-29a-3p ,Ltβr ,NF-κb ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 ,Cytology ,QH573-671 - Abstract
Abstract Background Gastric cancer (GC) is among the most common and deadliest cancers globally. Many long non-coding RNAs (lncRNAs) are key regulators of GC pathogenesis. This study aimed to define the role of HOXA-AS3 in this oncogenic context. Methods Levels of HOXA-AS3 expression in GC were quantified via qPCR. The effects of HOXA-AS3 knockdown on GC cells function were evaluated in vitro using colony formation assays, wound healing assays and transwell assays. Subcutaneous xenograft and tail vein injection tumor model systems were generated in nude mice to assess the effects of this lncRNA in vivo. The localization of HOXA-AS3 within cells was confirmed by subcellular fractionation, and predicted microRNA (miRNA) targets of this lncRNA and its ability to modulate downstream NF-κB signaling in GC cells were evaluated via luciferase-reporter assays, immunofluorescent staining, and western blotting. Results GC cells and tissues exhibited significant HOXA-AS3 upregulation (P
- Published
- 2021
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32. Research on the lean and swept optimization of a single stage axial compressor
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Zhongyi Wang, Feng Qu, Yanhua Wang, Yigang Luan, and Meng Wang
- Subjects
optimization ,axial compressor ,lean and swept ,stall margin ,Engineering (General). Civil engineering (General) ,TA1-2040 - Abstract
Compressor design is always a prevalent research issue as nowadays the compressor demands higher performance. Designing afresh a new compressor of higher aerodynamic performance will cost a tremendous amount of time and expense. Consequently, the wiser method of acquiring a higher performance compressor is to optimize a current compressor, discussed in this paper. First, a detailed numerical simulation of al compressor is done. A parametric rotor model is created and the variations of lean and swept parameters are limited. Then, an optimization calculation is carried out based on the combination of an artificial neural network and a genetic algorithm. The optimization iteration is started at three specified working points – a choke point, a design point and a near stall point – to acquire a comprehensive improved solution. A novel penalty function considering both pressure ratio and efficiency is constructed to find the optimal model. Finally, a detailed review is made of the original and the optimized compressor. The computational results show that the isentropic efficiency is successfully increased and the stall margin is remarkably improved. Ultimately, a detailed vortex structure analysis with increasing outlet pressure is discussed. This helps the performance increment mechanism to be understood further.
- Published
- 2021
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33. Are tumor-associated micro-angiogenesis and lymphangiogenesis considered as the novel prognostic factors for patients with Xp11.2 translocation renal cell carcinoma?
- Author
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Wenliang Ma, Jun Yang, Ning Liu, Xiaohong Pu, Feng Qu, Linfeng Xu, Xiaozhi Zhao, Xiaogong Li, Gutian Zhang, Hongqian Guo, Dongmei Li, and Weidong Gan
- Subjects
Micro-angiogenesis ,Lymphangiogenesis ,Renal cell carcinoma ,Xp11.2 translocation ,TFE3 ,Prognosis ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Abstract Background Tumor micro-angiogenesis and lymphangiogenesis are effective prognostic predictors in many solid malignancies. However, its role on Xp11.2 translocation RCC has not been fully elucidated. Herein, we purposed to explore the correlation between quantitative parameters of tumor-related micro-angiogenesis or lymphangiogenesis and the prognosis of Xp11.2 translocation renal cell carcinoma (Xp11.2 translocation RCC). Methods Tissue samples were obtained from 34 Xp11.2 translocation RCC and 77 clear cell renal cell carcinoma (ccRCC) between January 2007 and December 2018. Micro-angiogenesis was detected using CD34 antibody and quantified with microvessel density (MVD) and microvessel area (MVA), while the lymphangiogenesis in RCC was immunostained with D2–40 antibody and assessed using lymphatic vessel density (LVD) and lymphatic vessel area (LVA). The Kaplan-Meier method of survival analysis was used to estimate prognosis, and both univariate and multivariate analysis was performing using the Cox proportional hazards. Results The MVD and MVA of Xp11.2 translocation RCC in two detected areas (intratumoral and peritumoral area) were not significantly different from that of ccRCC (all P > 0.05). Notably, D2–40-positive lymphatic vessels of Xp11.2 translocation RCC were highly detected in the peritumoral area compared to the intratumoral area. Interestingly, the peritumoral LVD and LVA of Xp11.2 translocation RCC were higher than that of ccRCC (all P 0.05). Conclusions This study outlines that Xp11.2 translocation RCC is a highly vascularized solid RCC, characterized by rich lymph vessels in the peritumoral area. Quantitative parameters of micro-angiogenesis and lymphangiogenesis could not be considered as novel prognostic factors for patients with xp11.2 translocation RCC.
- Published
- 2020
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34. Selection and Identification of an ssDNA Aptamer for Fibroblast Activation Protein
- Author
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Xiaomin Zhang, Ge Yang, Yi Zhao, Xuyan Dai, Wenjing Liu, Feng Qu, and Yuanyu Huang
- Subjects
FAP ,aptamer ,CE ,SELEX ,cancer-associated fibroblasts ,Organic chemistry ,QD241-441 - Abstract
As a type II transmembrane serine protease, fibroblast activation protein (FAP) is specifically expressed on the surface of fibroblasts associated with a variety of epithelial-derived malignancies such as pancreatic cancer, breast cancer, and colon cancer. It participates in the processes of tumorigenesis, progression, and immunosuppression. FAP constitutes an important target for tumor treatment; however, the current studies on FAP are mainly related to structural characteristics, enzymatic properties, and biological functions, and aptamers of FAP have not been investigated. In this work, by using recombinant human FAP as the target, five candidate aptamers, which are AptFAP-A1, AptFAP-A2, AptFAP-A3, AptFAP-A4, and AptFAP-A5, were selected by capillary electrophoresis–systematic evolution of ligands by exponential enrichment (CE-SELEX), and their secondary structures were predicted to be mainly stem-loop. Moreover, the CE-laser-induced fluorescence (LIF) method was used to determine the equilibrium dissociation constant KD values between the FAP protein and candidate aptamers, and the KD value was in the low molar range. Finally, Cy5-labeled aptamers were co-incubated with human pancreatic cancer-associated fibroblasts highly expressing FAP protein, and confocal microscopy imaging showed that aptamer AptFAP-A4 had the highest affinities with the cells. The FAP aptamers screened in this study provide a promising direction for the development of rapid tumor diagnosis and targeted therapy.
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- 2023
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35. Results of active surveillance of foodborne diseases in Pudong New Area of Shanghai, 2015-2018
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Yaping REN, Huiping SHEN, Feng QU, and Pinqing BAI
- Subjects
foodborne diseases ,active surveillance ,pathogens ,Food processing and manufacture ,TP368-456 ,Nutrition. Foods and food supply ,TX341-641 - Abstract
Objective To understand the epidemic trend and characteristics of foodborne diseases caused by specific pathogens in Pudong New Area of Shanghai, so as to provide scientific evidence for disease prevention and control. Methods From 2015 to 2018, the infectious cases with diarrhea as the main complaint were collected from the sentinel hospital of foodborne disease active monitoring in Pudong New Area of Shanghai. Stool or anal swab samples were collected and tested for Vibrio parahaemolyticus, Salmonella, Shigella, diarrheogenic Escherichia coli, Campylobacter jejuni and Norovirus. At the same time, the profiles were collected and analyzed. Results In 2015-2018, 2 871 stool or anal swab samples of diarrhea cases were monitored and collected. The positive rate of pathogens was 23.55% (676/2 871), including Norovirus 20.04% (97/484), diarrheogenic Escherichia coli 11.84% (340/2 871), Campylobacter jejuni 7.21% (68/943), Vibrio parahaemolyticus 4.01% (115/2 871), Salmonella 3.27% (94/2 871) and Shigella 0.28% (8/2 871). The positive rate was higher in the third quarter, showing a significant peak in summer and autumn. Suspicious food was mainly mixed food (41.12%, 278/676), followed by aquatic animals and their products (22.19%, 150/676) and meat and meat products (10.95%, 74/676). Conclusion Norovirus and diarrheogenic Escherichia coli were the main pathogens of diarrhea cases in Pudong New Area of Shanghai. We should further improve the foodborne disease active monitoring system, carry out detailed epidemiological case investigation for specific pathogen positive cases, and provide technical support for effective prevention and control.
- Published
- 2020
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36. Effects of different N, P, K and Ca levels on tomato yield, quality and fertiliser use efficiency
- Author
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Feng Qu, Jiao Zhang, Xueqiang Ma, Junzheng Wang, Zixing Gao, and Xiaohui Hu
- Subjects
solanum lycopersicum l. ,soilless cultivation ,vegetable management ,comprehensive analysis ,greenhouse ,Plant culture ,SB1-1110 - Abstract
The experiment aimed to obtain a quadratic regression mathematical model of the comprehensive evaluation score of yield, quality, and four macroelements (N, K, P and Ca). The suitable nutrient solution was chosen and verified via computer simulation of the model and the highest comprehensive score in all treatments. Results showed that P, K and Ca had a positive effect on the comprehensive evaluation value of tomato, whereas N showed a negative effect. The optimal formula calculated using the regression equation could promote high-yield and high-quality tomato. The single-plant yield, soluble protein, vitamin C, total sugar, lycopene, and elemental utilisation of K and Ca in the tomato were 13.93, 78.95, 3.29, 20.98, 51.91, 16.69 and 24.14% higher than those in the special formula treatment of Japanese Yamazaki tomato, respectively. In summary, the optimal nutrient solution formula of tomato cultivation was obtained, in which the N, P, K and Ca levels were 24.83, 4.50, 9.49 and 5.73 mmol/L, respectively.
- Published
- 2020
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37. The suitability of NONO-TFE3 dual-fusion FISH assay as a diagnostic tool for NONO-TFE3 renal cell carcinoma
- Author
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Ning Liu, Wei Guo, Qiancheng Shi, Wenyuan Zhuang, Xiaohong Pu, Shaoyu Chen, Feng Qu, Linfeng Xu, Xiaozhi Zhao, Xiaogong Li, Gutian Zhang, Hongqian Guo, Weidong Gan, and Dongmei Li
- Subjects
Medicine ,Science - Abstract
Abstract NONO-TFE3 RCC is a subtype of Xp11.2 translocation renal cell carcinoma (RCC). So far, only a small amount of NONO-TFE3 RCC have been reported owing to lack of effective diagnosis methods. Utilizing the novel dual-fusion fluorescence in situ hybridization (FISH) probe reported here, 5 cases of NONO-TFE3 RCC were identified and were ultimately confirmed by RT-PCR. Histopathology, all 5 cases were consisted by sheets of epithelial cells and papillary architecture. The cytoplasm was abundantly clear, and nucleoli was not prominent. Besides, the nuclear palisading, subnuclear vacuoles and psammoma bodies were identified. The most distinctive features were strong positive TFE3 staining but equivocal split signals of the TFE3 probe, which might lead to the misdiagnosis of Xp11.2 translocation RCC. The median age and median tumor size of the five patients were 41.2 years and 3.6 cm, respectively. A median following follow-up of 27 months showed moderate disease progression and prognosis in NONO-TFE3 RCC patients. In conclusion, the present study demonstrates the effectiveness and reliability of the NONO-TFE3 dual-fusion FISH probe for diagnosing NONO-TFE3 RCC. Suspected cases of Xp11.2 translocation RCC showing biphasic pattern, strong positive TFE3 staining, and equivocal split signals in the TFE3 FISH assay indicated a possibility of NONO-TFE3 RCC.
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- 2020
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38. Differential Synergistic Interactions Among Four Different Wheat-Infecting Viruses
- Author
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Satyanarayana Tatineni, Jeff Alexander, and Feng Qu
- Subjects
barley stripe mosaic virus ,brome mosaic virus ,co-infection ,synergistic interaction ,Triticum mosaic virus ,virus–virus interaction ,Microbiology ,QR1-502 - Abstract
Field-grown wheat (Triticum aestivum L.) plants can be co-infected by multiple viruses, including wheat streak mosaic virus (WSMV), Triticum mosaic virus (TriMV), brome mosaic virus (BMV), and barley stripe mosaic virus (BSMV). These viruses belong to four different genera in three different families and are, hence, genetically divergent. However, the impact of potential co-infections with two, three, or all four of them on the viruses themselves, as well as the wheat host, has yet to be examined. This study examined bi-, tri-, and quadripartite interactions among these viruses in wheat for disease development and accumulation of viral genomic RNAs, in comparison with single virus infections. Co-infection of wheat by BMV and BSMV resulted in BMV-like symptoms with a drastic reduction in BSMV genomic RNA copies and coat protein accumulation, suggesting an antagonism-like effect exerted by BMV toward BSMV. However, co-infection of either BMV or BSMV with WSMV or TriMV led to more severe disease than singly infected wheat, but with a decrease or no significant change in titers of interacting viruses in the presence of BMV or BSMV, respectively. These results were in stark contrast with exacerbated disease phenotype accompanied with enhanced virus titers caused by WSMV and TriMV co-infection. Co-infection of wheat by WSMV, TriMV, and BMV or BSMV resulted in enhanced synergistic disease accompanied by increased accumulation of TriMV and BMV but not WSMV or BSMV. Quadripartite interactions in co-infected wheat by all four viruses resulted in very severe disease synergism, leading to the death of the most infected plants, but paradoxically, a drastic reduction in BSMV titer. Our results indicate that interactions among different viruses infecting the same plant host are more complex than previously thought, do not always entail increases in virus titers, and likely involve multiple mechanisms. These findings lay the foundation for additional mechanistic dissections of synergistic interactions among unrelated plant viruses.
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- 2022
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39. We miss you, we are all FFF--Mourns from the Chinese orthopaedic sports medicine community
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Jiangtao Dong, Feng Qu, Jingbin Zhou, Tianlong Huang, Yan Xu, Yongtao Mao, Xin Tang, Shurong Zhang, and Shiyi Chen
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Diseases of the musculoskeletal system ,RC925-935 - Published
- 2021
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40. Enzyme-Linked Aptamer Kits for Rapid, Visual, and Sensitive Determination of Lactoferrin in Dairy Products
- Author
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Fan Zhang, Hongxia Du, Linsen Li, Tengfei Li, Jing Wang, Zilei Chen, Mengmeng Yan, Chao Zhu, and Feng Qu
- Subjects
aptamer ,lactoferrin determination ,enzyme-linked aptamer assay ,colorimetric ,capillary electrophoresis ,Chemical technology ,TP1-1185 - Abstract
Lactoferrin (Lf), as a popular nutritional fortification in dairy products, has the ability regulate the body’s immune system and function as a broad-spectrum antibacterial, which is of great significance to the growth and development of infants and children. Herein, an indirect competitive enzyme-linked aptamer assay (ELAA) kit was established for rapid, sensitive, and visual determination of Lf in dairy products. In the construction, the Lf aptamer was conjugated with horseradish peroxidase (HRP) as the recognition probe and aptamer complementary strand (cDNA) were anchored onto the microplate as the capture probe. The recognition probes were first mixed with a sample solution and specifically bound with the contained Lf, then added into the microplate in which the free recognition probes in the mixture were captured by the capture probe. After washing, the remaining complex of cDNA/Aptamer/HRP in the microplate was conducted with a chromogenic reaction through HRP, efficiently catalyzing the substrate 3, 3′, 5, 5′-tetramethylbenzidine (TMB), therefore the color shade would directly reflect Lf concentration. Under the optimization conditions, a good linear relationship (R2, 0.9901) was obtained in the wide range of 25–500 nM with the detection limit of 14.01 nM and a good specificity, as well as the reliable recoveries. Furthermore, the ELAA kits achieved the Lf determination with an accuracy of 79.71~116.99% in eleven samples, which consisted of three kinds of dairy products: including goat milk powder, cow milk powder, and nutrition drop. Moreover, the results were also validated by the high-performance capillary electrophoresis (HPCE) method. The ELAA kit provides a simple and convenient determination for Lf in dairy products, and it is highly expected to be commercialized.
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- 2022
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41. Effects of Shoe Midfoot Bending Stiffness on Multi-Segment Foot Kinematics and Ground Reaction Force during Heel-Toe Running
- Author
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Ruiya Ma, Wing-Kai Lam, Rui Ding, Fan Yang, and Feng Qu
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midsole modification ,overground running ,foot kinematics ,running injuries ,footwear ,Technology ,Biology (General) ,QH301-705.5 - Abstract
We investigated how midfoot stiffness of running shoes influences foot segment kinematics and ground reaction force (GRF) during heel-toe running. Nineteen male rearfoot strike runners performed overground heel-toe running at 3.3 m/s when wearing shoes with different midfoot bending stiffnesses (low, medium, and high) in a randomized order. A synchronized motion capture system (200 Hz) and force plate (1000 Hz) were used to collect the foot-marker trajectories and GRF data. Foot kinematics, including rearfoot-lab, midfoot-rearfoot, forefoot-rearfoot, and forefoot-midfoot interactions, and kinetics, including GRF characteristics, were analyzed. Our results indicated that high midfoot stiffness shoes reduced the forefoot-rearfoot range of motion (mean ± SD; high stiffness, 7.8 ± 2.0°, low stiffness, 8.7 ± 2.1°; p < 0.05) and forefoot-midfoot range of motion (mean ± SD; high stiffness, 4.2 ± 1.1°, medium stiffness, 4.6 ± 0.9°; p < 0.05) in the frontal plane. No differences were found in the GRF characteristics among the shoe conditions. These findings suggest that an increase in midsole stiffness only in the midfoot region can reduce intersegmental foot medial-lateral movements during the stance phase of running. This may further decrease the tension of the foot muscles and tendons during prolonged exercises.
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- 2022
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42. Novel Nitric Oxide Donor Dinitroazetidine-Coumarin Hybrids as Potent Anti-Intrahepatic Cholangiocarcinoma Agents
- Author
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Zhihui Yu, Mengru Li, Shiqi Guo, Weijie Wang, Feng Qu, Yulei Ma, Hongrui Liu, and Ying Chen
- Subjects
intrahepatic cholangiocarcinoma ,NO donor ,dinitroazetidine-coumarin hybrids ,antitumor ,Organic chemistry ,QD241-441 - Abstract
Intrahepatic cholangiocarcinoma (iCC) is a serious liver cancer threatening human health. However, there are a few chemotherapeutic drugs for the treatment of iCC in the clinic. It is extremely urgent to develop new drugs for iCC. In this study, twenty dinitroazetidine and coumarin hybrids were synthesized and evaluated anti-iCC bioactivity as a new type of nitric oxide (NO) donors. Among them, compounds 2–5 and 21 showed a higher antiproliferative activity against RBE cell lines (human intrahepatic cholangiocarcinoma cell lines) and low cytotoxicity in nontumor cells (HOSEpiC and T29). The preliminary study of pharmacology mechanism indicated that compounds 2–5 and 21 could release effective concentration of NO in RBE cell lines, which leaded to inhibit the proliferation of RBE cell lines. The research results revealed that compound 3 inhibited the proliferation of RBE cell lines by inducing apoptosis and arresting cell cycle at G2/M phase. Additionally, compound 3 had acceptable metabolic stability. Therefore, compound 3 was merited to further explore for developing a desirable NO donor lead with anti-iCC activity.
- Published
- 2022
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43. A new risk-scoring system to predict Xp11.2 translocation renal cell carcinoma in adults
- Author
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Qiancheng Shi, Ning Liu, Yiqi Zhu, Feng Qu, Linfeng Xu, Xiaogong Li, Gutian Zhang, Hongqian Guo, Dongmei Li, and Weidong Gan
- Subjects
Medicine (General) ,R5-920 - Abstract
Objective The objective was to derive and validate a practical scoring system for preoperative diagnosis of Xp11.2 translocation renal cell carcinoma (RCC) in adults. Methods Epidemiology, symptomatology, and imaging methods were correlated between patients with common RCC and those with Xp11.2 translocation RCC using a derivation study (N = 6352) and a validation study (N = 127). Univariate analysis of risk factors was performed to derive a scoring system to predict the occurrence of Xp11.2 translocation RCC in adults. The Hosmer–Lemeshow goodness-of-fit test and receiver operating characteristic (ROC) curve were used to validate the scoring system. Results Based on odd ratios, three low-risk factors (sex, gross haematuria, and intratumoural calcification) and three high-risk factors (age, unenhanced computed tomography density, and enhancement pattern) were given weighted scores of 1 and 2, respectively. Patients who scored 3 to 5 points underwent an additional magnetic resonance imaging examination. The final scoring system had a sensitivity of 81.0% and a specificity of 98.0%. Conclusion We established a practical scoring system for the preoperative diagnosis of Xp11.2 translocation RCC in adults, which can be optimised through further clinical findings in the future.
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- 2021
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44. Drip irrigation and fertilization improve yield, uptake of nitrogen, and water-nitrogen use efficiency in cucumbers grown in substrate bags
- Author
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Feng Qu, Jingjing Jiang, Jiwen Xu, Tao Liu, and Xiaohui Hu
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cucumis sativus l. ,vegetable management ,crop nutrition ,soilless culture ,controlled environment agriculture ,Plant culture ,SB1-1110 - Abstract
This study was conducted to identify ideal irrigation and fertigation levels for maximum yields and profitability of cucumber grown in a substrate-bag cultivation system. The experiment was laid out in randomized complete-block design, with combinations of four drip irrigation rates (75, 100, 125, or 150% of crop evapotranspiration (ETc)) and three fertilization (F) levels (60, 100, or 125% of one dose of Yamazaki nutrient solution formula). The 'irrigation level × fertilization level' interaction significantly affected cucumber yield and nitrogen accumulation. The treatment combination of 125% ETc and 100% F promoted yield relatively best. Plants were grown in the 125% ETc and 125% F treatment combination accumulated the most nitrogen. The greatest nitrogen use efficiency (NUE) was observed in the 100% ETc plus 60% F treatment combination. Water use efficiency (WUE) decreased with increasing irrigation rate, and considering just one fertilization level. Through the multivariate regression analysis and the spatial analysis methods to evaluate yield, WUE, and NUE, we conclude that the combination of 13.54-23.78 g/plantand 37.71-52.59 L/plant were the best strategy of fertigation and irrigation for the production of drip-irrigated cultivated cucumber grown in substrate bags in spring.
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- 2019
- Full Text
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45. Identity Preserving Generative Adversarial Network for Cross-Domain Person Re-Identification
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Jialun Liu, Wenhui Li, Hongbin Pei, Ying Wang, Feng Qu, You Qu, and Yuhao Chen
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Person re-identification ,domain adaptation ,style transfer ,unsupervised learning ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 - Abstract
In this paper, we study the domain adaptive person re-identification(re-ID) problem: train a re-ID model on the labeled source domain and test it on the unlabeled target domain. It's known challenging due to the feature distribution bias between the source domain and target domain. The previous methods directly reduce the bias by image-to-image style translation between the source and the target domain in an unsupervised manner. However, these methods only consider the rough bias between the source domain and the target domain but neglect the detailed bias between the source domain and the target camera domains (divided by camera views), which contain critical factors influencing the testing performance of re-ID model. In this work, we particularly focus on the bias between the source domain and the target camera domains. To overcome this problem, a multi-domain image-to-image translation network, termed Identity Preserving Generative Adversarial Network (IPGAN) is proposed to learn the mapping relationship between the source domain and the target camera domains. IPGAN can translate the styles of images from the source domain to the target camera domains and generate many images with styles of target camera domains. Then the re-ID model is trained with the translated images generated by IPGAN. During the training of the re-ID model, we aim to learn the discriminative feature. We design and train a novel re-ID model, termed IBN-reID, in which Instance and Batch Normalization block (IBN-block) are introduced. Experimental results on Market-1501, DukeMTMC-reID and MSMT17 show that the images generated by IPGAN are more suitable for cross-domain re-ID. Very competitive re-ID accuracy is achieved by our method.
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- 2019
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46. Structural Analysis of Biomolecules through a Combination of Mobility Capillary Electrophoresis and Mass Spectrometry
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Muyi He, Pan Luo, Jie Hong, Xiaofeng Wang, Haimei Wu, Rongkai Zhang, Feng Qu, Ye Xiang, and Wei Xu
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Chemistry ,QD1-999 - Published
- 2019
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47. An Effective AUSM-Type Scheme for Both Cases of Low Mach Number and High Mach Number
- Author
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Nan Li, Feng Qu, Di Sun, and Guanghui Wu
- Subjects
shock anomaly ,AUSM ,all speeds ,AUSMAS ,computational fluid dynamics ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
A new scheme called AUSMAS (Advection Upstream Splitting Method for All Speeds) is proposed for both high speed and low speed simulation cases. For the cases of low speed, it controls the checkerboard decoupling by keeping the coefficient of the pressure difference to the order of O(Ma−1) in the mass flux. Furthermore, it is able to guarantee a high level of accuracy by keeping the coefficients of the dissipation terms to the order of O(Ma0) in the momentum flux. For the cases of high speeds, especially at supersonic and hypersonic speeds, it is able to avoid the appearance of the shock anomaly by controlling the coefficients of the density perturbation in the mass flux. AUSMAS is testified to have the following attractive properties according to various numerical tests: (1) robustness against the abnormal shock; (2) high resolution in discontinuity; (3) the appearance of the unphysical expansion shock is avoided; (4) high resolution and low dissipation at low speeds; (5) independent of any tuning coefficient. These properties determined that AUSMAS has great promise in efficiently and accurately simulating flows of all speeds.
- Published
- 2022
- Full Text
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48. Trajectory Generation and Optimization Using the Mutual Learning and Adaptive Ant Colony Algorithm in Uneven Environments
- Author
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Feng Qu, Wentao Yu, Kui Xiao, Chaofan Liu, and Weirong Liu
- Subjects
trajectory generation and optimization ,mutual learning ,adaptive ant colony algorithm ,2D-H map ,de-temperature function ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
Aiming at the trajectory generation and optimization of mobile robots in complex and uneven environments, a hybrid scheme using mutual learning and adaptive ant colony optimization (MuL-ACO) is proposed in this paper. In order to describe the uneven environment with various obstacles, a 2D-H map is introduced in this paper. Then an adaptive ant colony algorithm based on simulated annealing (SA) is proposed to generate initial trajectories of mobile robots, where based on a de-temperature function of the simulated annealing algorithm, the pheromone volatilization factor is adaptively adjusted to accelerate the convergence of the algorithm. Moreover, the length factor, height factor, and smooth factor are considered in the comprehensive heuristic function of ACO to adapt to uneven environments. Finally, a mutual learning algorithm is designed to further smooth and shorten initial trajectories, in which different trajectory node sequences learn from each other to acquire the shortest trajectory sequence to optimize the trajectory. In order to verify the effectiveness of the proposed scheme, MuL-ACO is compared with several well-known and novel algorithms in terms of running time, trajectory length, height, and smoothness. The experimental results show that MuL-ACO can generate a collision-free trajectory with a high comprehensive quality in uneven environments.
- Published
- 2022
- Full Text
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49. Scalar fields on pAdS
- Author
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Feng Qu and Yi-hong Gao
- Subjects
Physics ,QC1-999 - Abstract
We obtain a subgroup of the isometry group of pAdS (a p-adic version of AdS alternative to the Bruhat–Tits tree). We propose a candidate for the scalar bulk action and equation of motion on pAdS, and work out analytical expressions of the Green's functions for a particular choice of parameter together with an ansatz for general cases. The limiting behaviors of the Green's function are also studied. With their help, the convergence of small loops (whose radii are smaller than AdS length scale of pAdS) is analyzed. Keywords: Anti-de Sitter/conformal field theory correspondence, Gauge/gravity correspondence, p-adic number
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- 2018
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50. High-Precision SLAM Based on the Tight Coupling of Dual Lidar Inertial Odometry for Multi-Scene Applications
- Author
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Kui Xiao, Wentao Yu, Weirong Liu, Feng Qu, and Zhenyan Ma
- Subjects
simultaneous localization and mapping ,dual lidar inertial odometry ,IMU ,time synchronization ,tight coupling ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
Simultaneous Localization and Mapping (SLAM) is an essential feature in many applications of mobile vehicles. To solve the problem of poor positioning accuracy, single use of mapping scene, and unclear structural characteristics in indoor and outdoor SLAM, a new framework of tight coupling of dual lidar inertial odometry is proposed in this paper. Firstly, through external calibration and an adaptive timestamp synchronization algorithm, the horizontal and vertical lidar data are fused, which compensates for the narrow vertical field of view (FOV) of the lidar and makes the characteristics of vertical direction more complete in the mapping process. Secondly, the dual lidar data is tightly coupled with an Inertial Measurement Unit (IMU) to eliminate the motion distortion of the dual lidar odometry. Then, the value of the lidar odometry after correcting distortion and the pre-integrated value of IMU are used as constraints to establish a non-linear least-squares objective function. Joint optimization is then performed to obtain the best value of the IMU state values, which will be used to predict the state of IMU at the next time step. Finally, experimental results are presented to verify the effectiveness of the proposed method.
- Published
- 2022
- Full Text
- View/download PDF
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