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Purpose: Current computed tomography (CT)‐based lung ventilation imaging (CTVI) techniques derive a static ventilation image without temporal information. This research aims to develop a four‐dimensional CT (4DCT)‐based multiphase dynamic ventilation imaging framework capable of recovering the entire ventilation process throughout the breathing cycle for functional lung avoidance radiotherapy (FLART). Methods: A total of 15 free‐breathing thoracic 4DCT scans of lung or esophageal cancer patients were collected from the public datasets. The lung region of each phase image was first delineated, and then the mask‐free isotropic total variation image registration algorithm was used to derive the deformation vector fields between the end‐expiration (EE) phase and other phases. As a surrogate of ventilation, the voxel‐wise local expansion ratio of each phase relative to the EE phase was estimated using the parameterized Integrated Jacobian Formulation method in the EE phase coordinate. Lastly, the dynamic ventilation images were generated by warping these phase‐specific local expansion distributions with a same geometry into their respective breathing phases. Quantitative analysis, including interphase Spearman correlation coefficients, voxel‐wise, and regional‐wise expansion/contraction tracking, were performed to indirectly validate the proposed method. Results: The proposed method maintains the physiological meaning of ventilation on each phase and enables to recover the dynamic lung ventilation process. The mean interphase Spearman correlations ranged between 0.23 ± 0.20 and 0.93 ± 0.04 and decreased near the EE phase. Only 26.2% (2.59E + 6 out of 9.89E + 6) of lung voxels exhibited the same expansion/contraction pattern as the global lung. Qualitative and quantitative evaluations of the interphase ventilation distribution difference show that ventilation spatiotemporal heterogeneities generally exist during respiration. Conclusions: In contrast to conventional CTVI metrics, our method enables to extract additional phase‐resolved respiration‐correlated information and reflects the generally existed ventilation spatiotemporal heterogeneities. Subsequent studies with quantitative phase‐by‐phase cross‐modality evaluations will further explore its potential to deepen our understanding of lung function and respiration mechanics and also to facilitate more accurate implementation of FLART. [ABSTRACT FROM AUTHOR]

Establishing beneficial intestinal microbiota using autochthonous probiotics is a promising approach for disease control and growth regulation during fish rearing. Therefore, it is crucial to identify indigenous probiotics with high application potential in aquaculture. In this study, we screened Bacillus coagulans BC1, a strain with strong application potential. After a comprehensive safety assessment, diets containing varying doses of BC1 were formulated and administered to crucian carp. Subsequently, a feeding experiment was conducted to evaluate non-specific immune response, intestinal structure, microbiota, and challenge protection rate. The results demonstrate that oral supplementation of BC1 can lead to tissue-dependent upregulation of various serum immune enzymes and IgM levels, while significantly enhancing the expression of IL-1β , IL-10 , TNF-α , and TGF-β in various organs of crucian carp (p < 0.05). The BC1 diet effectively promoted intestinal morphology in crucian carp and improved resistance to Aeromonas veronii TH0426 infection. Intestinal microbiota analysis revealed that the oral addition of BC1 significantly changed the intestinal microbial community structure of crucian carp but did not clearly affect intestinal microbial diversity. Oral administration of BC1 significantly improved the relative abundance of Cetobacterium in the intestines of crucian carp; reduced the abundance of opportunistic pathogens such as Bacteroides , Vibrio and Aeromonas and effectively regulating the nutrient metabolism in intestinal microbiota. These results indicate that BC1 could regulate immune function, effectively improving the intestinal morphology and intestinal flora structure and function of crucian carp, and therefore is a potential candidate strain for aquatic feed additives. • B. coagulans strain BC1 with strong application potential in aquatic feed additive was obtained by in situ screening. • Oral BC1 effectively enhanced the non-specific immunity of crucian carp juvenile. • BC1 diet could regulate the structure and function of intestinal flora of crucian carp juvenile. [ABSTRACT FROM AUTHOR]

Purpose: Our purpose was to develop a deep learning-based computed tomography (CT) perfusion mapping (DL-CTPM) method that synthesizes lung perfusion images from CT images.Methods and Materials: This paper presents a retrospective analysis of the pulmonary technetium-99m-labeled macroaggregated albumin single-photon emission CT (SPECT)/CT scans obtained from 73 patients at Queen Mary Hospital in Hong Kong in 2019. The left and right lung scans were separated to double the size of the data set to 146. A 3-dimensional attention residual neural network was constructed to extract textural features from the CT images and reconstruct corresponding functional images. Eighty-four samples were randomly selected for training and cross-validation, and the remaining 62 were used for model testing in terms of voxel-wise agreement and function-wise concordance. To assess the voxel-wise agreement, the Spearman's correlation coefficient (R) and structural similarity index measure between the images predicted by the DL-CTPM and the corresponding SPECT perfusion images were computed to assess the statistical and perceptual image similarities, respectively. To assess the function-wise concordance, the Dice similarity coefficient (DSC) was computed to determine the similarity of the low/high functional lung volumes.Results: The evaluation of the voxel-wise agreement showed a moderate-to-high voxel value correlation (0.6733 ± 0.1728) and high structural similarity (0.7635 ± 0.0697) between the SPECT and DL-CTPM predicted perfusions. The evaluation of the function-wise concordance obtained an average DSC value of 0.8183 ± 0.0752 for high-functional lungs (range, 0.5819-0.9255) and 0.6501 ± 0.1061 for low-functional lungs (range, 0.2405-0.8212). Ninety-four percent of the test cases demonstrated high concordance (DSC >0.7) between the high-functional volumes contoured from the predicted and ground-truth perfusions.Conclusions: We developed a novel DL-CTPM method for estimating perfusion-based lung functional images from the CT domain using a 3-dimensional attention residual neural network, which yielded moderate-to-high voxel-wise approximations of lung perfusion. To further contextualize these results toward future clinical application, a multi-institutional large-cohort study is warranted. [ABSTRACT FROM AUTHOR]

Synthetic aperture imaging systems can be applied to equivalently get high-resolution images of traditional monolithic primary mirror systems with less weight and costs. Spatial modulation diversity (SMD), a newly developed post-processing technology applicable for such synthetic aperture systems, is very sensitive to Gaussian noise, which greatly limits its further application. In this paper, we propose an improved SMD strategy by introducing the deep denoising convolutional neural networks (DnCNN) into the image preprocessing to improve the robustness of SMD. Results of the numerical simulations demonstrate that the strategy proposed exhibits superior performance compared to the traditional SMD technique in terms of both the root-mean-square error (RMSE) of phase estimates and the structural similarity (SSIM) of image reconstruction. In view of the superiority and robustness, the method we proposed may have important application prospects in multi-aperture imaging systems. [ABSTRACT FROM AUTHOR]

Summary: Mud volcanoes (MVs) emit globally significant quantities of methane into the atmosphere, however, methane cycling in such environments is not yet fully understood, as the roles of microbes and their associated biogeochemical processes have been largely overlooked. Here, we used data from high‐throughput sequencing of microbial 16S rRNA gene amplicons from six MVs in the Junggar Basin in northwest China to quantify patterns of diversity and characterize the community structure of archaea and bacteria. We found anaerobic methanotrophs and diverse sulfate‐ and iron‐reducing microbes in all of the samples, and the diversity of both archaeal and bacterial communities was strongly linked to the concentrations of sulfate, iron and nitrate, which could act as electron acceptors in anaerobic oxidation of methane (AOM). The impacts of sulfate/iron/nitrate on AOM in the MVs were verified by microcosm experiments. Further, two representative MVs were selected to explore the microbial interactions based on phylogenetic molecular ecological networks. The sites showed distinct network structures, key species and microbial interactions, with more complex and numerous linkages between methane‐cycling microbes and their partners being observed in the iron/sulfate‐rich MV. These findings suggest that electron acceptors are important factors driving the structure of microbial communities in these methane‐rich environments. [ABSTRACT FROM AUTHOR]

The bacterial quorum sensing signals N-acyl homoserine lactone (AHL) signals are able to regulate a diverse array of physiological activities, such as symbiosis, virulence and biofilm formation, depending on population density. Recently, it has been discovered that the bacterial quorum sensing (QS) signal molecules can induce extensive response of higher eukaryotes including plants and mammalian cells. However, little is known about the response of fungi reacting to these bacterial signals. Here we showed that Saccharomyces cerevisiae, as an ancient eukaryote and widely used for alcoholic beverage and bioethanol production, exposed to short-chain 3-OC-HSL and long-chain C-HSL appeared obvious changes in morphology and ethanol tolerance. AHLs could increase the frequency of cells with bipolar and multipolar buds, and these changes did not present distinct differences when induced by different types (3-OC-HSL and C-HSL) and varied concentrations (200 nM and 2 μM) of AHLs. Further investigation by flow cytometer displayed that the cells untreated by AHLs reduced cell size (decreased FSC) and enhanced intracellular density (increased in SSC), compared with the AHLs-induced cells after incubation 6 h. In addition, the long-chain C-HSL could slightly increase the ethanol tolerance of S. cerevisiae while the short-chain HSL obviously decreased it. Our study would be valuable to further research on the interaction between prokaryotic and eukaryotic microbes, and be reference for industrial production of bioethanol. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the effects of conventional (Soxhlet; shaking extraction, SE) and green methods (microwave-assisted extraction, MAE; ultrasound-assisted extraction, UAE; subcritical extraction, SubE) on the oil yield, physicochemical properties, and lipid compositions of pomegranate seeds oil (PSO). The oil yield ranged from 11.32% to 15.66%, and the highest yield was obtained by Soxhlet. The results indicated that no significant differences (p > 0.05) were observed in refractive index and specific gravity of oils among different methods. PSO was abundant in polyunsaturated fatty acids. MAE and SubE samples exhibited comparatively higher contents of punicic acid (776.5 and 772.3 mg/g, respectively). Twelve triacylglycerol molecules were detected, in which punicic acid-punicic acid-punicic acid occupied the most proportion (47.85–48.51%). Lipid concomitants in PSO mainly contained squalene (1.20–1.72 mg/g), β-sitosterol (3.23–3.67 mg/g), and tocopherols (348.2–359.8 mg/100 g). Three tocopherols (α, γ, and δ) were identified in PSO with the dominance of γ-tocopherol (322.7–329.4 mg/100 g). UAE obtained relatively higher squalene and β-sitosterol contents, whereas SubE resulted in the highest tocopherol content in oils. These results demonstrated the technical feasibility of green extraction methods for obtaining PSO with high nutritional and valuable compounds. • Five extraction methods for pomegranate seed oil (PSO) were compared. • PSO was rich in unsaturated fatty acid, with punicic acid (Pu) as the main component. • PuPuPu was the predominant triacylglycerol molecules (> 47.85 % content) in PSO. • PSO involved lipid concomitants containing squalene, β-sitosterol, and tocopherol. • The three green methods selected can be well applied for the extraction of PSO. [ABSTRACT FROM AUTHOR]

In order to estimate the performance of opto-electrical tracking system, the integrated simuation platform should be developed, which is comprised of structure, control and optics. Based on the object track modeling, the tracking strategy for system is analyzed, and tracking optics principle and con- trol principle are studied separately. Finally, virtual reality is introduced. Integrated simulation platform is implemented in Matlab/Simulink. Using the platform, an example is analyzed, and the results accord with the fact. So the platform can be used in design and performance estimation in future. [ABSTRACT FROM AUTHOR]

For the dynamics of a rigid body with a fixed point based on the quaternion and the corresponding generalized momenta, a displacement-based symplectic integration scheme for differential-algebraic equations is proposed and applied to the Lagrange’s equations based on dependent generalized momenta. Numerical experiments show that the algorithm possesses such characters as high precision and preserving system invariants. More importantly, the generalized momenta based Lagrange’s equations show unique advantages over the traditional Lagrange’s equations in symplectic integrations. [ABSTRACT FROM AUTHOR]

The progressively intensifying misuse of antibiotics has caused a serious threat to the sustainable and sound development of aquaculture industry through the transfer of antibiotic resistance genes and the formation of multidrug-resistant bacteria, further leading to significant food and public health risks. Therefore, there is an urgent need for a new sustainable alternative treatment for antibiotics. Bacteriophages with high host specificity, have gradually attracted attention as relatively safe biological substitutes for antibiotics. However, there is a lack of systematic evaluation on the therapeutic effects and usage methods of bacteriophage treatment. In this meta-analysis, we investigated the therapeutic effect of bacteriophage therapy on aquatic animals and potential influencing factors, and analyzed the possibility of bacteriophages replacing antibiotics as a new biological control agent. A total of 3547 studies from five databases including PubMed, Web of Science, Science Direct, China National Knowledge Infrastructure, and Wanfang published within the past ten years were retrieved. After applying exclusion and inclusion criteria, a total of 32 studies with 67 datasets were included. Using a random-effects model, the results were pooled, and statistical heterogeneity between the data was assessed using Cochrane's Q test and I2 statistic. The results of the meta-regression and subgroup analysis showed that the therapeutic effect of bacteriophages was significantly influenced by multiplicity of infection (MOI) (p = 0.005, R2 = 11.97%) and treatment duration (p = 0.019, R2 = 8.00%). Moreover, there was no significant difference in the therapeutic effect between bacteriophages and antibiotics. In conclusion, our findings suggest that bacteriophages have great potential as alternatives to antibiotics in aquaculture. These results provide evidence-based guidance for the practical application of bacteriophage preparations in the aquaculture industry. • The evaluation of bacteriophage therapy in aquaculture. • Bacteriophages have great potential as alternatives to antibiotics in aquaculture. • The therapeutic effect of bacteriophages was significantly influenced by MOI and treatment duration. [ABSTRACT FROM AUTHOR]

Purpose: Radiation dermatitis (RD) is a common, unpleasant side effect of patients receiving radiation therapy. In clinical practice, the severity of RD is graded manually through visual inspection, which is labor intensive and often leads to large interrater variations. To overcome these shortcomings, this study aimed to develop an automatic RD assessment based on deep learning (DL) techniques that could efficiently assist the RD severity classification in clinical application.Methods and Materials: A total of 1205 photographs of the head and neck region were collected from patients with nasopharyngeal carcinoma (NPC) undergoing radiation therapy. The severity of RD in these photographs was graded by 5 qualified assessors based on the Radiation Therapy Oncology Group guidance. An end-to-end RD grading framework was developed by combining a DL-based segmentation network and a DL-based RD severity classifier, which are used for segmenting the neck region from the camera-captured photographs and grading, respectively. U-Net was used for segmentation and another convolutional neural network classifier (DenseNet-121) was applied to RD severity classification. Dice similarity coefficient was used to evaluate the performance of segmentation. Severity classification was evaluated by several metrics, including overall accuracy, precision, recall, and F1 score.Results: Results of segmentation showed that the averaged dice similarity coefficients were 91.2% and 90.8% for front and side view, respectively. For RD severity classification, the overall accuracy of test photographs was 83.0%. Our method accurately classified 90.5% of grade 0, 67.2% of grade 1, 93.8% of grade 2, and 100% of above grade 2 cases. The overall prediction performance was comparable with human assessors. There was no significant difference in accuracy when using manually or automatically segmented regions (P = .683).Conclusions: We have successfully demonstrated a DL-based method for automatic assessment of RD severity in patients with NPC. This method holds great potential for efficient and effective assessing and monitoring of RD in patients with NPC. [ABSTRACT FROM AUTHOR]

Purpose. This study aims to investigate the feasibility of different acquisition methods for time-resolved magnetic resonance fingerprinting (TR-MRF) in computer simulation. Methods. An extended cardiac-torso (XCAT) phantom is used to generate abdominal T1, T2, and proton density maps for MRF simulation. The simulated MRF technique consists of an IR-FISP MRF sequence with spiral trajectory acquisition. MRF maps were simulated with different numbers of repetitions from 1 to 15. Three different methods were used to generate TR-MRF maps: (1) continuous acquisition without delay between MRF repetitions; (2) continuous acquisition with 5 s delay between MRF repetitions; (3) triggered acquisition with variable delay between MRF repetitions to allow the next acquisition to start at different respiration phase. After the generation of TR-MRF maps, the image quality indexes including the absolute T1 and T2 values, signal-to-noise-ratio (SNR), tumor-to-liver contrast-to-noise ratio, error in the amplitude of diaphragm motion and tumor volume error were used to evaluate the reconstructed parameter maps. Three volunteers were recruited to test the feasibility of the selected acquisition method. Results. Dynamic MR parametric maps using three different acquisition methods were estimated. The overall and liver T1 value error, liver SNR in T1 and T2 maps, and tumor SNR from T1 maps from triggered method is statistically significantly better than the other two methods (p-value < 0.05). The other image quality indexes have no significant difference between the triggered method and the other two continuous acquisition methods. All image quality indexes exhibit no significant difference between the acquisition methods with 0 s and 5 s delay. The triggered method was successfully performed in three healthy volunteers. Conclusion. TR-MRF technique was investigated using three different acquisition methods in computer simulation where the triggered method showed better performance than the other two methods. The triggered method has been tested successfully in healthy volunteers. [ABSTRACT FROM AUTHOR]

Simple Summary: Dynamic chest radiographs offer a distinct advantage over traditional chest radiographs by integrating motion and functional data, elevating their significance in clinical diagnostics. This study introduces a pioneering technique employing deep neural networks to simulate respiratory lung motion and extract local functional details from single-phase chest X-rays, thereby enhancing lung cancer clinical diagnostic capabilities. Our research establishes the viability of generating patient-specific respiratory motion profiles from single-phase chest radiographs. The evaluation of results from the network developed here underscores its substantial accuracy and fidelity, affirming its robustness in providing valuable supplementary insights into pulmonary function. In this study, we present an innovative approach that harnesses deep neural networks to simulate respiratory lung motion and extract local functional information from single-phase chest X-rays, thus providing valuable auxiliary data for early diagnosis of lung cancer. A novel radiograph motion simulation (RMS) network was developed by combining a U-Net and a long short-term memory (LSTM) network for image generation and sequential prediction. By utilizing a spatial transformer network to deform input images, our proposed network ensures accurate image generation. We conducted both qualitative and quantitative assessments to evaluate the effectiveness and accuracy of our proposed network. The simulated respiratory motion closely aligns with pulmonary biomechanics and reveals enhanced details of pulmonary diseases. The proposed network demonstrates precise prediction of respiratory motion in the test cases, achieving remarkable average Dice scores exceeding 0.96 across all phases. The maximum variation in lung length prediction was observed during the end-exhale phase, with average deviation of 4.76 mm (±6.64) for the left lung and 4.77 mm (±7.00) for the right lung. This research validates the feasibility of generating patient-specific respiratory motion profiles from single-phase chest radiographs. [ABSTRACT FROM AUTHOR]

Accurate and robust prostate segmentation in transrectal ultrasound (TRUS) images is of great interest for ultrasound-guided brachytherapy for prostate cancer. However, the current practice of manual segmentation is difficult, time-consuming, and prone to errors. To overcome these challenges, we developed an accurate prostate segmentation framework (A-ProSeg) for TRUS images. The proposed segmentation method includes three innovation steps: (1) acquiring the sequence of vertices by using an improved polygonal segment-based method with a small number of radiologist-defined seed points as prior points; (2) establishing an optimal machine learning-based method by using the improved evolutionary neural network; and (3) obtaining smooth contours of the prostate region of interest using the optimized machine learning-based method. The proposed method was evaluated on 266 patients who underwent prostate cancer brachytherapy. The proposed method achieved a high performance against the ground truth with a Dice similarity coefficient of 96.2% ± 2.4%, a Jaccard similarity coefficient of 94.4% ± 3.3%, and an accuracy of 95.7% ± 2.7%; these values are all higher than those obtained using state-of-the-art methods. A sensitivity evaluation on different noise levels demonstrated that our method achieved high robustness against changes in image quality. Meanwhile, an ablation study was performed, and the significance of all the key components of the proposed method was demonstrated. [ABSTRACT FROM AUTHOR]

• In local denoising, the nonlocal WDF filter provides better results. • The WDF filter can be realized with a hardware implementation, such as an optical system. • Simple filters, such as apertures and Gaussian-weighted averages, can be highly effective in reducing noise. Nonlocal means denoising (NLM) and block-matching and 3D filtering (BM3D) have become the most popular algorithms for image processing. The disadvantage of these methods is that they cannot be realized by hardware implementation. The Wigner distribution function (WDF) has advantages such as explicit physical meaning, spatial frequency distribution of each pixel, and suitability for optical implementation. In recent years, the wide-field imaging system has been used extensively in multiple situations such as aviation, medicine, and traffic. Large-field images often have multiple point spread functions (PSF) and local random noise. However, the results have shown that most nonlocal filters have inadequate effects on local noise filtering. This paper analytically examines the Wigner transform of a multi-Gaussian function and investigates the effects of cross-term and noise on filter reconstruction in image processing. Based on the results, a new space-variant filter with a simple mathematical formula is proposed and applied to local high-frequency noise filtering. Since the filter is closely related to the intensity distribution in the spatial and frequency domains, it provides a simple way to process local noise while simultaneously preserving the high-frequency information of the image. [ABSTRACT FROM AUTHOR]

To understand the characteristics, source apportionment, and regional transport of volatile organic compounds (VOCs) and ozone (O 3) in a typical city with severe air pollution in central China, we observed and analyzed 115 VOC species at an urban site in Zhengzhou from 29 July to 26 September 2021. During this period, observation- and emission-based approaches revealed that Zhengzhou was in a VOC-limited regime. The average concentration of total VOCs (TVOCs) was 162.25 ± 71.42 μg/m3, dominated by oxygenated VOCs (OVOCs, 34.49%), alkanes (24.29%), and aromatics (19.49%). Six VOC sources were identified using positive matrix factorization (PMF) model, including paint solvent usage (25.32%), secondary production (24.11%), industrial production (19.22%), vehicle exhaust (16.18%), biogenic emission (8.87%), and combustion (6.30%). To assess the regional contribution and source apportionment of VOCs and O 3 , Comprehensive Air Quality Model with Extensions (CAMx) with the Ozone Source Apportionment Technology (OSAT) was used for simulation. Results showed that the VOCs were significantly affected by local emissions (about 70%), while O 3 was mainly attributed to regional and super-regional transport. Regarding multi-directional regional transport of VOCs and O 3 , dominant contributions were from the northeast and east-northeast directions, and O 3 contributions were also predominantly from the east and east-southeast directions. In terms of source apportionment, the transportation and industrial sectors (including solvent usage) were the major contributors to O 3 and VOCs. To alleviate VOCs and O 3 pollution, transportation and industrial emission reduction should be strengthened, and regional coordination, especially from the northeast to east-southeast directions, should be emphasized in addition to local management. [Display omitted] • 115 VOC species, including 21 OVOCs, were measured and analyzed in Zhengzhou. • Local emissions mainly affected VOCs (∼70%) rather than O 3. • Regional contributions of VOCs and O 3 were mainly from the NE and ENE directions. • Transportation and industrial sectors were the major contributors to VOCs and O 3. [ABSTRACT FROM AUTHOR]

When a beam moves through a curved tube, there exists a large number of contacts between the beam and the inner wall of the tube. Usually, it is necessary to use fine Lagrangian meshes to discretize the beam for possible contact area in order to obtain sufficiently accurate results, even if the contact is only once for a very short time. Accordingly, the computation process is very time-consuming due to the large number of degrees of freedom (DOF) of the discretized system. To solve this problem, an Arbitrary Lagrangian-Eulerian (ALE) formulation of a Timoshenko beam based on geometrically exact beam theory, which considers the rotation around the axis of the beam, is presented in this paper. In this formulation, the mesh nodes of the beam are not associated with the material points, which provides the flexibility to mesh the beam freely. For this reason, the ALE mesh nodes can be arranged along the tube and constrained to move just within the corresponding tube cross section. The axial movement of the beam can be described by the material points flowing through the axially constrained mesh nodes. In so doing, only the beam in the high-curvature section of the tube needs to be finely meshed, resulting in a significant reduction of the DOF of the whole system. Several examples are presented and discussed to demonstrate the correctness and efficiency of the proposed method. [ABSTRACT FROM AUTHOR]

The FPSS (fusion power shutdown system) provides a safety emergency shutdown system terminating the ITER (international thermonuclear experimental reactor). It has a reservoir of impurity gas and a dedicated tube for the impurity gas injection. In the preliminary design stage, the FPSS is studied as a sealed gas injection system, it is a supersonic and high pressure flow field. The transient flow of the system is analyzed with a commercial CFD code, ANSYS ® FLUENT in this paper. To satisfy the functional requirement, the injected gas volume of the VV (vacuum vessel) is predicted from a series of tank pressures in 3s. The influence of initial tank pressures, vessel pressure and flow times of the FPSS is quantified. CFD data is compared with the experimental activities and the discrepancy is acceptable. All the results will be used for optimized design of the FPSS. [ABSTRACT FROM AUTHOR]

A noised phase-unwrapping method is presented by using the Wigner distribution function to filter the phase noise and restore the gradient of the phase map. By using Poisson's equation, the unwrapped phase map was obtained. Compared with the existing methods, the proposed method is theoretically simple, provides a more accurate representation, and can be implemented in light-field hardware devices, such as Shack-Hartmann sensors. [ABSTRACT FROM AUTHOR]

Quorum sensing has been widely applied to enhance the energy recovery of bioelectrochemical system as a sustainable pathway to enhance communication between cells and electrodes. However, how signalling molecules (acyl-homoserine lactones, AHLs) regulate the microbial community to improve hydrogen generation in microbial electrolysis cells (MECs) is not well understood, especially the subsequent influence on interspecies relationships among not only electrode-respiring bacteria but also hydrogen scavengers. Understanding AHL regulation in a complicated and actual biofilm system will be valuable for future applications of microbial electrochemical technology. Herein, we added short-chain AHLs (3OC6) to regulate the biofilm community on bio-electrodes in MECs. As a result, hydrogen yields were enhanced with AHL addition, increasing by 5.57%, 38.68%, and 81.82% with varied external voltages (0.8 V, 0.6 V, and 0.4 V, respectively). Accordingly, overall reactor performance was enhanced, including coulombic efficiency, electron recovery efficiency, and energy efficiency. Based on an electrochemical impedance spectra analysis, the structured biofilm under simple nutrient conditions (acetate) showed a lower internal resistance with AHL addition, indicating that the microbial communities were altered to enhance electron transfer between the biofilm and electrode. The change in the cathodic microbial structure with more electrochemically active bacteria and fewer hydrogen scavengers could contribute to a higher electron recovery and hydrogen yield with AHL addition. The regulation of the microbial community structure by AHLs represents a potential strategy to enhance electron transfer and hydrogen generation in bioelectrochemical systems. [ABSTRACT FROM AUTHOR]

Non-line-of-sight (NLOS) imaging techniques have garnered significant interest in recent years for their ability to reconstruct obscured scenes. This type of imaging typically needs numerous temporal histograms, which require thousands of scans on the relay surface. Reconstructing obscured targets using several channels, i.e., capturing echoes from a few positions of the relay surface, is an attractive prospect but has so far been restricted to localization applications. Herein, we propose a rectangle-based data-driven method and first demonstrate that the 2D size of the hidden target can be detected even with as few as 2 or 3 detectors by exploiting the information inside an echo signal. Specifically, we conceptualize the occluded target as a rectangle representing the target size and train a multi-layer perceptron to learn the correspondence of the hidden scene from the generated data, in which the method can directly respond to unknown targets. Both numerical simulations and experiments are performed to evaluate the feasibility of this method. Furthermore, this work provides a feasible way of detecting hidden scene without scanning. [Display omitted] Reconstructing obscured objects using several channels without scanning is an attractive prospect but has thus far been restricted to localization applications. Herein, we propose a rectangle-based data-driven method which conceptualize the occluded target as a rectangle, and first demonstrates that the 2D size of the hidden target can be detected even with as few as 2 or 3 detectors by exploiting the information inside an echo signal. (a) shows a schematic diagram of the hidden scene, where P L is left bound the target and B L i is the left side of the box. (b) represents the recorded temporal histograms which contains information about the obscured target, where t P c is the closest ToF of the hidden target on the histogram, and t P f is the farthest ToF of the hidden target. (c) is a photo of the hidden scene. (d) is a depth image of the hidden scene as a front view, generated by the rectangle-based (multi-layers perceptron) MLP. • Proposes a rectangle-based data-driven method to associate echoes and target size. • Reconstructs the non-line-of-sight target 2D size using few detection channels. • Conceptualizes the occluded target as a rectangle representing the target size. • Provides a feasible way of detecting hidden scene using fixed laser and few detectors. [ABSTRACT FROM AUTHOR]

Background: Most available four‐dimensional (4D)‐magnetic resonance imaging (MRI) techniques are limited by insufficient image quality and long acquisition times or require specially designed sequences or hardware that are not available in the clinic. These limitations have greatly hindered the clinical implementation of 4D‐MRI. Purpose: This study aims to develop a fast ultra‐quality (UQ) 4D‐MRI reconstruction method using a commercially available 4D‐MRI sequence and dual‐supervised deformation estimation model (DDEM). Methods: Thirty‐nine patients receiving radiotherapy for liver tumors were included. Each patient was scanned using a time‐resolved imaging with interleaved stochastic trajectories (TWIST)–lumetric interpolated breath‐hold examination (VIBE) MRI sequence to acquire 4D‐magnetic resonance (MR) images. They also received 3D T1‐/T2‐weighted MRI scans as prior images, and UQ 4D‐MRI at any instant was considered a deformation of them. A DDEM was developed to obtain a 4D deformable vector field (DVF) from 4D‐MRI data, and the prior images were deformed using this 4D‐DVF to generate UQ 4D‐MR images. The registration accuracies of the DDEM, VoxelMorph (normalized cross‐correlation [NCC] supervised), VoxelMorph (end‐to‐end point error [EPE] supervised), and the parametric total variation (pTV) algorithm were compared. Tumor motion on UQ 4D‐MRI was evaluated quantitatively using region of interest (ROI) tracking errors, while image quality was evaluated using the contrast‐to‐noise ratio (CNR), lung–liver edge sharpness, and perceptual blur metric (PBM). Results: The registration accuracy of the DDEM was significantly better than those of VoxelMorph (NCC supervised), VoxelMorph (EPE supervised), and the pTV algorithm (all, p < 0.001), with an inference time of 69.3 ± 5.9 ms. UQ 4D‐MRI yielded ROI tracking errors of 0.79 ± 0.65, 0.50 ± 0.55, and 0.51 ± 0.58 mm in the superior–inferior, anterior–posterior, and mid–lateral directions, respectively. From the original 4D‐MRI to UQ 4D‐MRI, the CNR increased from 7.25 ± 4.89 to 18.86 ± 15.81; the lung–liver edge full‐width‐at‐half‐maximum decreased from 8.22 ± 3.17 to 3.65 ± 1.66 mm in the in‐plane direction and from 8.79 ± 2.78 to 5.04 ± 1.67 mm in the cross‐plane direction, and the PBM decreased from 0.68 ± 0.07 to 0.38 ± 0.01. Conclusion: This novel DDEM method successfully generated UQ 4D‐MR images based on a commercial 4D‐MRI sequence. It shows great promise for improving liver tumor motion management during radiation therapy. [ABSTRACT FROM AUTHOR]

Purpose: To investigate a novel deep-learning network that synthesizes virtual contrast-enhanced T1-weighted (vceT1w) magnetic resonance images (MRI) from multimodality contrast-free MRI for patients with nasopharyngeal carcinoma (NPC).Methods and Materials: This article presents a retrospective analysis of multiparametric MRI, with and without contrast enhancement by gadolinium-based contrast agents (GBCAs), obtained from 64 biopsy-proven cases of NPC treated at Hong Kong Queen Elizabeth Hospital. A multimodality-guided synergistic neural network (MMgSN-Net) was developed to leverage complementary information between contrast-free T1-weighted and T2-weighted MRI for vceT1w MRI synthesis. Thirty-five patients were randomly selected for model training, whereas 29 patients were selected for model testing. The synthetic images generated from MMgSN-Net were quantitatively evaluated against real GBCA-enhanced T1-weighted MRI using a series of statistical evaluating metrics, which include mean absolute error (MAE), mean squared error (MSE), structural similarity index (SSIM), and peak signal-to-noise ratio (PSNR). Qualitative visual assessment between the real and synthetic MRI was also performed. Effectiveness of our MMgSN-Net was compared with 3 state-of-the-art deep-learning networks, including U-Net, CycleGAN, and Hi-Net, both quantitatively and qualitatively. Furthermore, a Turing test was performed by 7 board-certified radiation oncologists from 4 hospitals for assessing authenticity of the synthesized vceT1w MRI against the real GBCA-enhanced T1-weighted MRI.Results: Results from the quantitative evaluations demonstrated that our MMgSN-Net outperformed U-Net, CycleGAN and Hi-Net, yielding the top-ranked scores in averaged MAE (44.50 ± 13.01), MSE (9193.22 ± 5405.00), SSIM (0.887 ± 0.042), and PSNR (33.17 ± 2.14). Furthermore, the mean accuracy of the 7 readers in the Turing tests was determined to be 49.43%, equivalent to random guessing (ie, 50%) in distinguishing between real GBCA-enhanced T1-weighted and synthetic vceT1w MRI. Qualitative evaluation indicated that MMgSN-Net gave the best approximation to the ground-truth images, particularly in visualization of tumor-to-muscle interface and the intratumor texture information.Conclusions: Our MMgSN-Net was capable of synthesizing highly realistic vceT1w MRI that outperformed the 3 comparable state-of-the-art networks. [ABSTRACT FROM AUTHOR]

• High-precision but large-range automatic image stacking technique. • Minimizing the manual operation and additional optical modules in engineering applications. • The dynamic metric optimization strategy avoids falling into local extremes. • It's universal applicability regardless of the arrangements, aperture numbers, and coherence. Image stacking is the first step of alignment of the sparse aperture telescopes. We propose an all-purpose automatic image stacking technique using dynamic metric stochastic parallel gradient descent algorithm (DM-SPGD). With the image stacking modeled as an optimization problem, the dynamic metric functions consisting of a distance metric and an energy metric are defined. According to the judgment of the spot state, the two metrics, both computed from the focal spot at each step, are switched dynamically to perform SPGD optimization. By use of the dynamic metric functions, DM-SPGD can exactly and quickly correct any-amplitude tip/tilt errors, regardless of the array arrangements, aperture numbers and coherence as verified by simulation. In addition, jitter and changes in piston brought about by the environment have no effect on the image stacking. Multiple closed-loop image stacking experiments are performed, demonstrating that the offsets of randomly distributed spots can be all controlled below 0.5 pixels within 300 iterations (within 30 s). [ABSTRACT FROM AUTHOR]

• A new IGRT technique based on the "CBCT-only" mode is proposed to improve the treatment effectiveness of esophageal cancer radiotherapy. This mode relies on CBCT images and utilizes different deep learning models to synthesize corresponding pseudo-CT and pseudo-PET images. The synthesized data is used to assist clinicians in tasks such as delineation, dose calculation, and positioning verification during radiotherapy, thus avoiding various sources of human error introduced in current clinical radiotherapy practices. • A dual-domain parallel deep learning model with attention waning mechanism (AWM-PNet) is proposed to obtain pseudo-CT images from CBCT. The parallel image synthesis approach can effectively leverage the information from sinogram and spatial domains. The attention waning mechanism captures important features and contextual information in a more efficient manner. • A GAN model with a prior region aware mechanism (PRAM-GAN) is employed to synthesize pseudo-PET images from CT. By incorporating knowledge from clinical experts regarding tumor location and shape, the mechanism assists the model to learn the representation of tumor region features in the PET image domain and their relationship with other soft tissues. • The accuracy of the pseudo-medical images synthesized by the models proposed in this study has been verified in terms of anatomical representation and dosimetric evaluation. Purpose To minimize the various errors introduced by image-guided radiotherapy (IGRT) in the application of esophageal cancer treatment, this study proposes a novel technique based on the 'CBCT-only' mode of pseudo-medical image guidance. Methods The framework of this technology consists of two pseudo-medical image synthesis models in the CBCT→CT and the CT→PET direction. The former utilizes a dual-domain parallel deep learning model called AWM-PNet, which incorporates attention waning mechanisms. This model effectively suppresses artifacts in CBCT images in both the sinogram and spatial domains while efficiently capturing important image features and contextual information. The latter leverages tumor location and shape information provided by clinical experts. It introduces a PRAM-GAN model based on a prior region aware mechanism to establish a non-linear mapping relationship between CT and PET image domains. As a result, it enables the generation of pseudo-PET images that meet the clinical requirements for radiotherapy. Results The NRMSE and multi-scale SSIM (MS-SSIM) were utilized to evaluate the test set, and the results were presented as median values with lower quartile and upper quartile ranges. For the AWM-PNet model, the NRMSE and MS-SSIM values were 0.0218 (0.0143, 0.0255) and 0.9325 (0.9141, 0.9410), respectively. The PRAM-GAN model produced NRMSE and MS-SSIM values of 0.0404 (0.0356, 0.0476) and 0.9154 (0.8971, 0.9294), respectively. Statistical analysis revealed significant differences (p < 0.05) between these models and others. The numerical results of dose metrics, including D98 %, Dmean, and D2 %, validated the accuracy of HU values in the pseudo-CT images synthesized by the AWM-PNet. Furthermore, the Dice coefficient results confirmed statistically significant differences (p < 0.05) in GTV delineation between the pseudo-PET images synthesized using the PRAM-GAN model and other compared methods. Conclusion The AWM-PNet and PRAM-GAN models have the capability to generate accurate pseudo-CT and pseudo-PET images, respectively. The pseudo-image-guided technique based on the 'CBCT-only' mode shows promising prospects for application in esophageal cancer radiotherapy. [ABSTRACT FROM AUTHOR]

Mechanically robust optical homogeneous polyimide (PI) films with desirable atomic oxygen (AO) erosion duration were fabricated by initially synthesizing amine-functionalized hyperbranched polysiloxane (NH2-HBPSi), then reinforcing the pristine polyimide skeleton with it via copolycondensation reactions. NH2-HBPSi macromolecule imparts desirable AO survivability to the resulting hybrids. The mass loss per unit area of hybrid films had a downward trend with rising NH2-HBPSi content and AO dose before the complete silica protective layer was formed. It has been proven by the experiments in an underground simulated AO environment. It decreased to 1% of that of pristine polyimide when NH2-HBPSi accounted for 30% of the solid content after 24 h AO attack. The stable thickness uniformity that can meet the Rayleigh criterion was achieved in a 30 wt% HBPSi PI film, mainly due to the selection of the best process parameters. Meanwhile, 30 wt% HBPSi PI demonstrates satisfactory mechanical properties, with a tensile strength of 228.9 MPa and elongation at break of 7.3%. The characterization of scanning electron microscopy confirmed that pristine polyimide was substantially eroded after AO exposure while the surface morphology of 30 wt% HBPSi polyimide showed no evident change. The low AO erosion yield and prominent film thickness uniformity may find extensive usage in ultra-lightweight space diffractive optical elements (DOE) working in low earth orbit (LEO). [ABSTRACT FROM AUTHOR]

Optical sparse aperture imaging technology has promising applications in the next generation of high-resolution imaging systems, but the phasing errors correction of sparse aperture is an urgent problem to be addressed. In this paper, we propose a blind structured-illumination super-resolution imaging system using a sparse aperture as the transmitter to overcome phasing errors and obtain higher resolution. In our scheme, an unknown pattern is projected onto the object by a sparse aperture system. By translating the unknown pattern, a sequence of modulated raw images is obtained. Based on these low-resolution raw images, the super-resolution object and the unknown illumination pattern are jointly estimated by the Adam algorithm. Here we show, both in the simulation and experiment, the resolution of reconstructions using sparse aperture as transmitter are similar to those using monolithic lens. Furthermore, we validate that the proposed method can protect the reconstruction effect from piston error and widen the tolerance range of tip/tilt error (peak-valley values) up to 0.5λ. At the same time, our proposed system can also alleviate to some extent the problem of mid-frequency modulation transfer function (MTF) attenuation that exists in sparse aperture imaging. Our approach not only simplifies the process of constructing synthetic aperture system, but also provides a novel application for synthetic aperture systems. • The introduction of structured illumination improves the resolution of synthetic aperture imaging. • Protect the reconstruction effect from piston error in the sparse aperture transmitter. • Widen the tolerance range for imaging system of tip/tilt error in sparse aperture transmitter. • Alleviate to some extent the problem of mid-frequency attenuation that exists in sparse aperture imaging. [ABSTRACT FROM AUTHOR]

The Arbitrary Lagrangian–Eulerian (ALE) formulation provides a high-efficiency approach to simulate the moving contact behaviors in mechanical systems using the relative movement between material points and mesh nodes. Two approaches have been widely adopted to obtain the governing equations of ALE elements, namely (i) Lagrange's equations for non-material volume and (ii) the principle of virtual work. Indeed, consistent numerical results should be obtained through these two approaches; however, their mathematical expressions are quite different at first glance. In this paper, the equivalence of the above-mentioned two approaches demonstrated analytically for a general case and a specific example of three-dimensional two-node ALE cable elements. Additionally, the existence and disappearance conditions for additional terms L 1 and L 2 of the generalized inertial forces, which distinguish the ALE formulation from the Lagrangian formulation, are explicitly presented. They are physically caused by the material flow through the boundary and mathematically caused by the dependence of the mass matrix M on the material coordinates p 1 and p 2 . When no mass is transported through the boundary surface or the kinetic energy of the material points flowing into or out of the control volume is zero, L 1 and L 2 automatically disappear, and the governing equations degenerate to the classical form of Lagrange's equations. Finally, an example of preloaded wire rope with variable length is used to verify the above conclusions. [ABSTRACT FROM AUTHOR]

In drilling engineering, it is extremely challenging to drill a prescribed wellbore over several thousand meters. One of the main difficulties arises from accurately predicting and controlling the directional drilling performance, caused by the complex nonlinear dynamics of the slender drilling assembly and its interactions with the surrounding rocks. Nowadays, the simplified analytical geometry method, which has been adopted as the industry standard, can merely offer a rough estimation of the drilling direction, while the high-accuracy finite element method is computationally inefficient. This study is intended to provide a straightforward prediction of the drilling direction for a long drilling distance accurately and efficiently by proposing a dynamical simulation method based on the flexible multibody approach. Three techniques were adopted to achieve the critical objective of the paper. First, an Arbitrary Lagrangian–Eulerian formulation was used to provide a new approach to balance the efficiency and accuracy. Additionally, it can perfectly simulate the realistic drilling operation that drill pipes are continuously added to the drill string one by one through dynamically inserting new beam elements into the existing model. Second, the whole drill string and its interaction with the wellbore were all considered to carry out a high-fidelity simulation. Finally, the bit–rock interaction model was introduced to offer a straightforward way of evaluating the steerability of drilling assemblies. The presented method and model were validated by the consistency between the simulated wellbore trajectory and the in-field experimental data and are ready to be applied in drilling tools design, real-time drilling simulation, and drilling direction control. [ABSTRACT FROM AUTHOR]

This paper presents a method for solving the differential equation of light rays. We define functions which represent Cartesian coordinates and take the arc length as the independent variable. Then the ray equation can be transformed to convenient pattern by these defined functions. This proposed method avoids the complex transformation and interpolation in traditional techniques. So the coordinate value can be directly solved using the computational software. The solution procedure has been demonstrated by a ray tracing simulation in an axial gradient refractive-index media. And the computer code can be developed. Comparing with the analytical solution shows that the error of the proposed method is small. [ABSTRACT FROM AUTHOR]

Abstract The underlying dynamics of microbial (bacteria and archaea) communities ecologically responding to an applied potential are critical to achieving the goal of enhancing bioenergy recovery but are not sufficiently understood. We built a MEC-AD mode that increased methane production rate by several times (max. 3.8 times) during the startup period compared to control AD, changed the absence or presence of external voltage to provide the pre-, dur-, and post- samples for microbial analysis. From a time and spatially dependent community analysis of electrode-respiring bacteria and methanogens, the corresponding Geobacter developed under the influence of external voltage, pairing with methanogens in the anodic and cathodic biofilm to generate methane. Additionally, at the cathode, the Alkaliphilus (basophilic bacteria) also correspondingly shifted alongside the change of external voltage. The mcrA sequencing confirmed a change in the dominant microbe from acetoclastic (mostly Methanosarcina mazei LYC) to hydrogenotrophic methanogens (mostly basophilic Methanobacterium alcaliphilum) at the cathode with 0.8 V voltage. Overall, the external voltage not only enriched the functional microbes including electrogens and methanogens but also indirectly shifted the composition of the bacterial and archaeal community via disturbing the pH condition. The predictive functional profiling indicated that the cathodic methanogenesis principally followed the metabolism pathway of the hydrogenotrophic methanogens, suggesting the F420 co-enzyme could be the key mediate for electron transfer. All data suggested that the electric stimulation would change and maintain the micro-environmental conditions to shift the bacterial/archaeal community. Graphical abstract Unlabelled Image Highlights • Electricity-driven induced a core-shell structure of microbial communities. • Hydrogenotrophs and acetoclastic methanogens enriched at cathodic community. • Basophilic Alkaliphilus and Methanobacterium alcaliphilum were influenced by electricity. [ABSTRACT FROM AUTHOR]

Gear contact problems are characterized by a large number of possible contact scenarios while only a few of them are simultaneously active at a given time. When applying the model order reduction method in gear contact problems, the addition of a static shape vector for each possibly-loaded boundary Degree of Freedom (DOF) will enable the contact being accurately described but may be computationally expensive when the number of boundary DOF is large. On the other hand, omission of boundary DOF, though might be computationally efficient, will result in a slow convergence. The objective of this paper is to develop a modeling technique based on Arbitrary Lagrangian Eulerian (ALE) formulation to reduce DOF while providing accurate gear meshing contact simulation. Four techniques are adopted to achieve the critical objective of the paper. First, the low-frequency approximation is attained by ignoring fixed boundary normal modes. Second, under the framework of ALE formulation, only the mesh nodes of four engaging tooth-faces are defined as boundary nodes during the whole process resulting in a great reduction of DOF of the system. Then, the calculation of inertial force and Jacobian matrix are simplified by ignoring the inertial forces resulted from deformation. Finally, a four-step high-efficiency contact algorithm is adopted to reduce the number of contact pairs and accelerate the detection process. The performance of the proposed method is demonstrated with four gear contact problems and correlated with commercial nonlinear finite element software. [ABSTRACT FROM AUTHOR]

Cathodic methanogenesis is a promising method for accelerating and stabilising bioenergy recovery in anaerobic processes. The change in composition of microbial (especially methanogenic) communities in response to an applied potential—and especially the associated pH gradient—is critical for achieving this goal, but is not well understood in cathodic biofilms. We found here that the pH-polarised region in the 2 mm surrounding the cathode ranged from 6.9 to 10.1, as determined using a pH microsensor; this substantially affected methane production rate as well as microbial community structure. Miseq sequencing data of a highly conserved region of the mcrA gene revealed a dramatic variation in alpha diversity of methanogens concentrated in electrode biofilms under the applied potential, and confirmed that the dominant microbes at the cathode were hydrogenotrophic methanogens (mostly basophilic Methanobacterium alcaliphilum ). These results indicate that regional pH variation in the microenvironment surrounding the electrode is an ecological niche enriched with Methanobacterium . [ABSTRACT FROM AUTHOR]

Understanding the buckling behaviors of rods confined in a finite space is of paramount importance in a diversity of engineering fields. In this paper, theoretical analyses, numerical simulations and experimental measurements are combined to investigate the buckling and postbuckling of a long rod confined in a circular tube. Under uniaxial compression, the initially straight rod first buckles into a sinusoidal shape, followed by the occurrence of snap-through instability or helical buckling, which leads to a complicated, three-dimensional configuration consisting of serially connected sinusoids and helices. A new theoretical model is presented to analyze the sinusoidal and helical buckling processes of the confined rod. The complete load–displacement curve of the buckled system during loading and unloading can be well predicted by the present theory. The critical conditions are obtained for the occurrence of the sinusoidal buckling and the sinusoid–helix transitions of buckling modes. It is found, both theoretically and experimentally, that the morphological evolution during unloading exhibits distinctly different features from that during loading due to the peculiar energetic features of snap-through instability. A flexible multibody dynamics method on the basis of the geometrically exact beam theory is employed to numerically explore the buckling behavior of slender rods and to reveal the underlying energetic mechanisms. The theoretical, numerical, and experimental results agree with each other very well. The theoretical model and the numerical method presented in this work are expected to analyze some other problems of confined rods, beams, and their combined systems. [ABSTRACT FROM AUTHOR]

Polymer brushes modified surfaces have been widely used for protein immobilization and isolation. Modification of membranes with polymer brushes increases the surface concentration of affinity ligands used for protein binding. Albumin is one of the transporting proteins and shows a high affinity to bile acids. In this work, the modified membranes with cholic acid-containing polymer brushes can be facilely prepared by the immobilization of cholic acid on the poly(2-hydroxyethyl methacrylate) grafted microporous polypropylene membranes (MPPMs) for affinity adsorption of albumin. ATR/FT-IR and X-ray photoelectron spectroscopy were used to characterize the chemical composition of the modified membranes. Water contact angle measurements were used to analyze the hydrophilic/hydrophobic properties of the membrane surface. The modified MPPMs show a high affinity to albumin and have little non-specific adsorption of hemoglobin. The dynamic binding capacity of albumin in the continous-flow system increases with the cycle number and feed rate as the binding degree of cholic acid is moderate. The highest binding capacity of affinity membranes is about 52.49 g/m 2 membrane, which is about 24 times more than the monolayer binding capacity. These results reveal proteins could be captured in multilayers by the polymer brushes containing affinity ligands similar to the polymer brushes containing ion-exchange groups, which open up the potential of the polymer brushes containing affinity ligands in protein or another components separation. And the cholic acid containing polymer brushes modified membranes has the promising potential for albumin separation and purification rapidly from serum or fermented solution in medical diagnosis and bioseparation. [ABSTRACT FROM AUTHOR]

Quorum sensing (QS) has been extensively studied as a cell–cell communication system, where small chemical signal molecules (acylhomoserine lactones, AHLs) can regulate the bacterial communications in bioelectrochemical systems via chemical signaling and electric signaling. In this study, electrochemical activity of bio-anode is substantially promoted by adding two kinds of AHLs with different chain length at the stage of community formation in microbial electrolysis cells (MECs). Hydrogen yield increase is observed by adding of two chain length AHLs, 3-oxo-hexanoyl-homoserine lactone (3OC6-HSL) and 3-oxo-dodecanoyl homoserine lactone (3OC12-HSL). A higher MEC current is acquired with addition of 3OC6-HSL than 3OC12-HSL at a fixed voltage of 0.8 V (vs. SHE). The highest yield is up to 3.8 ± 0.2 mol H 2 mol −1 acetate at 10 μM 3OC6-HSL, which is increased 29% over control MECs. Evaluated on applied voltage, energy efficiency is increased to 171.6 ± 21.3% with short chain AHL, however, no significant improvement is performed on energy efficiency and coulombic efficiency with long-chain AHL. The study shows that bioelectrochemical characteristics of MECs varied on the chain length of AHL signal molecules and short-chain AHLs have a more positive effect on electron transfer and energy recovery in MECs. [ABSTRACT FROM AUTHOR]

The coregistration of complex image pairs is a very important step in interferometric synthetic aperture radar (InSAR) data processing. This article proposes a coregistration method based on the stochastic parallel gradient descent (SPGD) algorithm. Stochastic parallel perturbations are imposed on the translation coefficients of the polynomial coregistration model to make the performance evaluation function converge to a global extremum, which allows the translation coefficients to be obtained, and then the coregistration is achieved after resampling. Data processing of images from Kashgar and Mount Etna show that the proposed method is effective and robust. Furthermore, a series of experiments is designed to evaluate the convergence characteristics of the proposed method, which indicates that it has a stable convergence process and good robustness. [ABSTRACT FROM AUTHOR]

Reducing the noise level of fiber optic gyroscope (FOG) has been paid much attention. The relative intensity noise (RIN) of the light source is a dominant noise source and different methods have been used to reduce the RIN. However, the performance of the RIN suppression methods suffering from parameter variation is rarely discussed. In this paper, we introduced a method that uses the period LMS (PLMS) adaptive filter in the FOG system with noise subtraction implementation to ensure the sensor's performance in varying environment. By analyzing the sampled detector signals in the system, the parameters in the system are determined based on the convergence requirement and noise performance of PLMS. Simulations as well as experiments of a FOG system with the PLMS algorithm implemented in the signal processing board are used to verify the feasibility of the method. The performance comparison between the PLMS filter and the predetermined Wiener filter in different temperature is tested and analyzed, which reveals the variability of the system parameters and verifies the necessity and ability of the introduced method to adapt to the varying environment. [ABSTRACT FROM AUTHOR]

In this paper, we consider a two-sided vibro-impact energy harvester described as a forced cylindrical capsule inclined at a horizontal angle, and the motion of the ball inside the capsule follows from the impacts with the capsule ends and gravity. Two distinct cases of dynamical behavior are investigated: the nondissipative and dissipative cases, where the dissipation is given by a restitution coefficient of impacts. We show that the dynamics of the system are described by the use of a 2D implicit map written in terms of the variables' energy and time when the ball leaves the moving capsule ends. More precisely, in the nondissipative case, we analytically show that this map is area-preserving and the existence of invariant curves for some rotation number with Markoff constant type is proved according to Moser's twist theorem in high energy. The existence of invariant curves implies that the kinetic energy of the ball is always bounded, and hence, the structure of system is not destroyed by the impacts of the ball. Furthermore, by numerical analysis we also show that the dynamical behavior of this system is regular, mainly containing periodic points, invariant curves and Aubry–Mather sets. After introducing dissipation, the dissipation destroys the regular dynamical behavior of the nondissipative case, and a periodic point with low energy is generated. [ABSTRACT FROM AUTHOR]

• We propose a simple but efficient pre-processing algorithm capable of extracting translation positions of the structure light directly from raw images of Incoherent pattern-illumination Fourier ptychography (IFP), termed translation position extracting (TPE). • TPE removes the requirement of IFP for prior knowledge of translation positions, thus further relaxing the practical conditions. Both simulation and experiment are performed to demonstrate its effectiveness. • The calculation cost of the TPE algorithm is similar to the cross-correlation, which is far lower than the existing translation extraction algorithm based on iterative optimization. Incoherent Pattern-illuminated Fourier ptychography (IFP) is a newly developed super-resolution method, where accurate prior knowledge of translation positions is essential for image reconstruction. To release this limitation, we propose a pre-processing algorithm capable of extracting translation positions of the structure light directly from raw images of IFP, termed translation position extracting (TPE). TPE mainly involves two steps. First, the speckle parts mixed in the acquired raw images, in which the illumination motion is encoded, are isolated by intensity averaging and division. Then the cross-correlations of the speckle dataset are computed to determine the shift positions. TPE-IFP improves the previous IFP by removal of the requirement for prior knowledge of translation positions. Its effectiveness is demonstrated by obtaining high-quality super-resolution images in absence of location information in both simulations and experiments. By further relaxing the practical conditions, the proposed TPE may accelerate the applications of IFP. What's more, as a pre-processing approach, TPE might also contribute to the estimation of pattern positions for the similar speckle-based imaging. [ABSTRACT FROM AUTHOR]

[Display omitted] • Time-dependent multibody dynamic with interval uncertainty parameters is considered. • Response surface method systematically incorporates signal decomposition technique. • Each sampled response is decomposed into several vibration terms and a trend. • Agent models of vibration term's amplitude and phase as well as the trend are built. • Long-time and high-precision uncertainty analysis is achieved. Studying multibody dynamic systems, a common way to evaluate the effects of uncertainty parameters is the response surface method, which works by building a polynomial surrogate model at each time instant through a set of input and corresponding output responses. However, a dynamic response always becomes a more and more complicated function of uncertainty parameters with the increase of time; as a result, the fitted surrogate model often fails to provide an accurate approximation at later time instants. This paper suggests that a dynamic response is composed of several vibration components and one trend component. Therefore, it is better to decompose the response into its multiple components, and then fit the amplitude and phase of each vibration component, as well as the trend component, using polynomial functions. By combining the response surface method with signal decomposition techniques, such as Hilbert-Huang transform and local mean decomposition, this study proposes a novel methodology to develop a high-accuracy surrogate model for interval uncertainty analysis. The proposed methodology will degenerate to the conventional response surface method when the dynamic response is a trend component. Three mechanical systems – a Duffing oscillator, a single pendulum and a slider-crank model – are used to confirm the effectiveness of the proposed methodology. This methodology provides a new technical pathway to improve the accuracy of dynamical uncertainty analysis. [ABSTRACT FROM AUTHOR]

Abstract: A novel pathway for homocoupling of terminal alkynes has been described using cyclopalladated ferrocenylimine 1 or 2/CuI as catalyst in the air. This catalytic system could tolerate several functional groups. The palladacycle 2 in the presence of n-Bu4NBr as an additive could be applied to Sonogashira cross-coupling reaction of aryl iodides, aryl bromides, and some activated aryl chlorides with terminal alkynes under amine- and copper-free conditions, mostly to give moderate to excellent yields. [Copyright &y& Elsevier]

In many control systems, the most effective method to improve the performance of the closed-loop system is by enhancing the gain of the control system, which results in a wide control bandwidth. However, in the control system of a charge-coupled-device-based tracking loop for a fast steering mirror, the bandwidth of the closed loop is greatly limited by the large time delay of the TV tracker. Additionally, the time delay leads to instability of the system when the closed-loop system has high gain. We propose a new feedforward control to compensate some errors related to the time delay of the tracker, meanwhile improving the performance of the closed-loop fast steering mirror system. The control structure we propose includes two closed loops; a tracking loop and a fast position loop. The fast position loop is produced using an eddy current sensor, and the tracking loop is the outer loop, enveloping the fast position loop. The feedforward signal is estimated from the signal of the eddy current sensor and the TV tracker, which is added to the input of the fast position loop. Experimental results show that our proposed feedforward system can effectively enhance trajectory tracking and pointing performance. [ABSTRACT FROM AUTHOR]

• The system combines the advantages of multi vision and synthetic aperture imaging. • In this system, besides a high-resolution image captured by synthetic aperture system, lower-resolution images with parallax can be obtained by multi-vision system. • By fusing the high-resolution image and lower-resolution images, a high precision measurement can be achieved. A new system that combines multi-vision system and synthetic aperture system is proposed to improve the measurement of small-scale or longer-range object. In the system, the parallax information is recorded by multi-vision system, meanwhile, a higher optical resolution image is obtained by synthesizing several optical apertures of multi-vision system to increase the effective aperture. By fusing the higher resolution image into the parallax images, we can acquire higher resolution images with parallax information from which the measurement can be improved greatly. As an example, a trinocular vision system improved by synthetic aperture has been studied experimentally. Results show that the method can improve the resolution in detection about two times and perform more accurate measurement than traditional multi-vision system. [ABSTRACT FROM AUTHOR]

• An efficient multibody model of arresting cable systems is proposed. • ALE formulation is used to model the moving contact between tailhook/pulley and cable. • More than one order of magnitude acceleration is achieved with high accuracy. Arresting cable systems (ACS) are widely used in aircraft carriers to decelerate an aircraft with high landing velocity in a limited runway length. Considering the complexity of the arresting process, it is extremely challenging to accurately and efficiently predict system dynamic behaviors, such as the arresting distance of aircrafts. In this paper, a comprehensive multibody dynamic model of ACS is proposed, where Arbitrary Lagrangian Eulerian (ALE) formulation is adopted to efficiently simulate the tailhook/pulley-cable moving contact in ACS. In our model, a moving fine mesh of the ALE cable, which tracks the real-time position of the tailhook, is used to accurately capture the contact behaviors between them, while evenly-distributed coarse meshes are used in non-contact areas, thereby greatly reducing DOFs and contact pairs. Additionally, the pulley joint is used to simulate the cable-sheave moving contact, where contact details are completely neglected and the ALE cable node is fixed to the dimensionless sheave point. Finally, the accuracy and efficiency of the proposed method are verified through three numerical tests with correlation to the conventional Lagrangian formulation. [ABSTRACT FROM AUTHOR]

• We demonstrate that using only a single deep convolutional neural network (DCNN) is sufficient to detect pistons from broadband extended images. To the best of our knowledge, the technique, reported in this paper, has never been reported. • Compared to other piston sensing methods using neural network, the reported technology being able to discern pistons directly from the broadband intensity summations rather than the intensities of separated wavelengths uses only a single DCNN, which extremely relaxes the optics complexity. • Above all, we believe this paper is suitable for optics and lasers in engineering. It is crucial for sparse aperture systems to preserve imaging quality, which can be addressed when fast corrections of pistons within a fraction of a wavelength are available. In this paper, we demonstrate that only a single deep convolutional neural network is sufficient to extract pistons from wide-band extended images once being appropriately trained. To eliminate the object characters, the feature vector is calculated as the input by a pair of focused and defocused images. This method possesses the capability of fine phasing with high sensing accuracy, and a large-scale capture range without the use of combined wavelengths. Simple and fast, the proposed technique might find wide applications in phasing telescope arrays or segmented mirrors. [ABSTRACT FROM AUTHOR]

• An efficient multibody model of 3D helical gear-shaft systems is proposed. • Low-frequency approximation and ALE formulation are used to reduce DOFs. • Dynamic equations are simplified and contact detection process is accelerated. • One order of magnitude acceleration is achieved with high accuracy. The dynamics of helical gear-shaft systems are characterized by three-dimensional (3D) meshing contacts that have significant variations in the location and size of the contact area, resulting in noise that is unavoidably transmitted to the gearbox through the shaft. Accurate and efficient predictions of the dynamic behaviors of helical gear and shaft are indispensable in reliable and cost-effective gearbox design. Available analytical methods, though computationally feasible, cannot consider multi-point contacts and uneven tooth-load distribution. In contrast, the finite element (FE) method provides a high-fidelity approach to compute the dynamic behaviors of a general gear-shaft system at high expenses of computation. This paper aims to establish a high-efficiency multibody dynamic model for 3D contacts in helical gear-shaft systems, in which the helical gear is pertinently represented under the framework of Arbitrary Lagrangian Eulerian formulation and the shaft is discretized by 3D Timoshenko beam elements. The computational efficiency is greatly improved through the following four steps. First, the low-frequency approximation technique is adopted to reduce the degrees of freedom (DOFs) resulting from the fixed boundary normal modes. Second, under the framework of ALE formulation, only the FE nodes of three meshing tooth-faces are defined as boundary nodes. Then, the dynamic equations and Jacobian matrix are simplified by ignoring the inertial forces associated with deformation. Finally, a two-step algorithm is adopted to accelerate the contact detection process. The accuracy and efficiency of the proposed method are demonstrated through five numerical tests with correlation to commercial nonlinear finite element software. [ABSTRACT FROM AUTHOR]

Fig. 5 Model of double-stage PSP Aiming at insufficiency in the passive and active disturbance suppression of the precision stabilized platform (PSP) system, in this study, a novel cascading double-stage PSP is designed and analyzed. Compared with the traditional structure, a new secondary PSP is provided to improve the disturbance suppression capability of the system over the full frequency range. The stabilizing mechanism of the secondary PSP is discussed in detail through dynamic modeling analysis of the double-stage PSP. This method can be used to solve the difficult compromise between the mechanical resonance and the control bandwidth in the design of the PSP with flexible support structure. Meanwhile, due to the reaction force of the primary PSP on the secondary PSP, the controlled object of the secondary PSP will be subjected to uncertain perturbation. Therefore, a robust control design method with a model is proposed to solve control problem of the secondary PSP. Theoretical and experimental results show that the secondary PSP brings better active and passive disturbance suppression ability for the stability control of the primary PSP. [ABSTRACT FROM AUTHOR]