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The accuracy of conventional target-based camera calibration depends on the detection of feature points. To improve the calibration accuracy in the flat field, this paper proposes an innovative calibration method based on encoded phase-shifting fringe (PSF) patterns. By using arbitrary quadrilateral interpolation, the relationship between a point on the virtual phase plane and the corresponding four original phase points is determined, establishing a mapping between the simplified original phase field and the virtual phase field. This spatial relationship can be used for accurate camera calibration. The proposed research investigates the details of the PSF based camera calibration method and demonstrates its accuracy and effectiveness through experiments. The evaluation of this method includes the checkerboard edge length variance analysis and the linear distance analysis of the checkerboard fit, both of which serve as validation metrics. Camera distortion is described by the phase distribution, and the average phase error after correction is less than 0.001 pixels (px). • A method of accurately calibrating camera by virtual phase is proposed. • The high precision of the phase-shifting fringe ensures reliable calibration. • The phase distribution error was effectively described. • Two analysis methods of edge length variance and linear distance are proposed. [ABSTRACT FROM AUTHOR]

• An adaptive neural network control with less computation is proposed to compensate the system uncertainty. • The control system with proposed control law and adaptive law is proved as uniform ultimate bounded using Lyapunov method • The effects of the number of hidden nodes on adaptive neural network control of robot manipulators are discussed. • A new approach is proposed to obtain the optimal number of hidden nodes for the adaptive neural network control. In this paper, an adaptive neural network control with optimal number of hidden nodes and less computation is proposed for approximating the system uncertainty and tracking the trajectory of robot manipulators. Unlike the existing researches on adaptive neural network for robot manipulators, whose number of hidden nodes is fixed and determined through the trial and error, a new approach is proposed to obtain the optimal number of hidden nodes, in which the number of hidden nodes adapts to the trajectory variations and is capable of catching up with the optimal value and minimizing the tracking error. The proposed control scheme can avoid overfitting and underfitting problems and guarantee a better trajectory tracking. Mathematical proof for stability and convergence of the system is presented using Lyapunov method. In the end, simulations are performed to illustrate the effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]

[Display omitted] • The abnormal local and long-range FCD in MCI compared with HCs. • The reversed FCD was found in MCI after treatments of acupoint-related moxibustion. • After moxibustion treatment, the MoCA scores of MCI were improved. Mild cognitive impairment (MCI) is a general neurodegenerative disease. Moxibustion has been shown to have remarkable effect on cognitive improvement, however, less is known about the effect of moxibustion on MCI and its underlying neural mechanism. This study aimed to investigate the ameliorative brain network in MCI after treatments of acupoint-related moxibustion. Resting-state functional MRI were derived from 47 MCI patients and 30 healthy controls (HCs). Patients were randomized as Tiaoshen YiZhi (TSYZ, n = 27) and sham (SHAM, n = 20) acupoint moxibustion groups. Functional connectivity density (FCD) method and repeated-measures two-way analysis of variance (ANOVA) were performed to ascertain the interaction effects between groups (TSYZ and SHAM) and time (baseline and post-treatment). Abnormal FCD was examined between baseline and post-treatment in TSYZ and SHAM groups, respectively. Compared with HCs, MCI showed altered FCD in the middle frontal cortex (MFC), inferior frontal cortex, temporal pole, thalamus and middle cingulate cortex. After moxibustion treatment in MCI, 1) a significant time-by-groups interaction was observed in the medial prefrontal cortex (mPFC); 2) abnormal long-range FCD (lrFCD) in the mPFC and MFC were modulated in TSYZ group; 3) significantly improved clinical symptoms; 4) changed lrFCD in the MFC was significantly negatively correlated with the increased Montreal Cognitive Assessment scores in TSYZ group. These imaging findings suggest that treatments of acupoint-related moxibustion could improve lrFCD in certain regions related to self-related cognitive and decision making. Our study might promote understanding of MCI neural mechanisms and expand the clinical application of moxibustion in MCI. [ABSTRACT FROM AUTHOR]

Abstract: The m-plane GaN (11¯00) epilayers have been grown on LiAlO2 (100) substrate by a two-step growth method using a metal-organic chemical vapor deposition (MOCVD) system. The GaN buffer layer is introduced to overcome the drawbacks of thermal instability of LiAlO2 (LAO), and to relieve the strains due to large thermal mismatch between LAO and GaN. The results of X-ray diffraction (XRD) and polarized Raman scattering spectra demonstrate that the GaN (11¯00) epilayer is single crystal as the growth temperature of the buffer layer is in the range of 850–950°C. Moreover, it is found that the surface nitridation process on LAO substrate can result in the formation of the GaN poly-crystalline films, which is due to the unintentional growth of a thin layer of c-phase AlN on LAO surface. [Copyright &y& Elsevier]

The microfluidic platform offers an exclusive environment compatible with different analytical tools to investigate crystallization processes. Moreover, microfluidic devices allow precise and convenient control of crystallization conditions at nano or meso scales, making them suitable for pharmaceutical and energy applications. These miniaturized screening devices can be effective during drug discovery stages for screening active ingredients available on micro/milligram scales. In this review, we discuss the advancements and applications of microfluidics platforms in the development of crystallization processes, including measurement of crystal growth and nucleation rates, screening of co-crystals, polymorphs and morphology, synthesis of nanocrystals, and determination of metastable zones and solubility. In addition, the latest microfluidics setups for high-throughput screening and lab-on-chip enhancements with sensors and automation are presented in this review. Lastly, an outlook on how microfluidic platforms can be adapted to improve workflow in crystallization process development is presented. [Display omitted] • Droplet-based microfluidics and microtiters cannot maintain supersaturation. • Continuous microfluidics with cyclonic flow can maintain supersaturation. • State-of-the-art of microfluidic platforms for crystallization is presented. • Parallel processing can improve the throughput of integrated microfluidics. • Microfluidics can be automated by hybridization with instrumentation and sensors. [ABSTRACT FROM AUTHOR]

• This study investigated altered functional connectivity (FC) of the periaqueductal gray (PAG) subregions in CD patients with and without abdominal pain. • This study found that FC between PAG and certain regions had correlation relationship with the pain degree. • This study revealed the disrupt communication between the PAG and default mode network (DMN) in CD patients with abdominal pain. Abdominal pain in Crohn's disease (CD) has been known to be associated with changes in the central nervous system. The periaqueductal gray (PAG) plays a well-established role in pain processing. However, the role of PAG-related network and the effect of pain on the network in CD remain unclear.Resting-state functional magnetic imaging (fMRI) data were collected from 24 CD patients in remission with abdominal pain, 24 CD patients without abdominal pain and 28 healthy controls (HCs). Using the subregions of PAG (dorsomedial (dmPAG), dorsolateral (dlPAG), lateral (lPAG) and ventrolateral (vlPAG)) as seeds, the seed-based FC maps were calculated and one-way analysis of variance (ANOVA) was performed to investigate the differences among the three groups.Results showed that the group differences were mainly involved in the FC of the vlPAG with the precuneus, medial prefrontal cortex (mPFC) as well as orbitofrontal cortex (OFC), and the FC of the right lateral PAG (lPAG) with the precuneus, inferior parietal lobule (IPL), angular gyrus and premotor cortex. The FC values of all these regions decreased successively in the order of HCs, CD without abdominal pain and CD with abdominal pain. The pain score was negatively correlated with the FC of the l/vlPAG with the precuneus, angular gyrus and mPFC in CD patients with abdominal pain.This study implicated the disrupt communication between the PAG and the default mode network (DMN). These findings complemented neuroimaging evidence for the pathophysiology of visceral pain in CD patients. [ABSTRACT FROM AUTHOR]

Abstract To intelligently control the parameters of a semiconductor pulsed seed source, a novel scheme is presented involving commercial electronic chips as switching devices to drive a semiconductor laser (SL). By combining theoretical analysis and rate-equation theory, we construct a mathematical model of the SL. Further, a pulsed laser module with real-time tunable optical pulse parameters is designed and implemented. The tunable pulse width ranges from 90 ps (PS) to continuous wave, and the tunable pulse repetition rate is 0–10 MHz. the SL temperature drift is less than 0.07 °C. The experimental results verify the feasibility of the design scheme, and the theoretical analysis and simulation results guide the generation of high-quality optical pulses. [ABSTRACT FROM AUTHOR]

Highlights • Using an erbium-doped photonic crystal fiber was used as a gain medium. • The stable laser output has wavelength step lengths below 0.02 nm. • The laser can align the acetylene absorption peak with high precision. • The laser had a maximum fluctuation in wavelength less than 6 pm (2h). • The peak power standard deviation was ∼0.03 dB during the 2 h experimental time. Abstract Narrow line-width fiber lasers are useful in gas-sensing, but systems that are both tunable and stable are rare. Here, we describe a single-wavelength ring cavity erbium-doped photonic crystal fiber laser (ED-PCFL) that can align the acetylene (C 2 H 2) gas absorption peak with high precision and a maximum deviation less than 0.012 nm. Rather than using a combination of erbium-doped fiber and a strong nonlinear fiber, ED-PCF was used as a gain medium to achieve a stable single-wavelength output based on the non-linear polarization rotation effect (NPR). This was selected because ED-PCF has a strong nonlinear effect. We added the dual polarization controllers (PCs) to weaken the homogeneous broadening based on the traditional tunable filter (TF) filtering structure. The results show that these steps improve the tunability of the laser wavelength and enhance the stability of the light source. The final laser had a side-mode suppression ratio as high as 60 dB over 45 nm with a maximum fluctuation in wavelength less than 6 pm. The peak power standard deviation was ∼0.03 dB during the 2 h experimental time. The peak power response of ED-PCFL was studied as a function of C 2 H 2 concentrations, and the calculated R-squared value was 0.993. This means that the ED-PCFL is suitable for C 2 H 2 sensing. [ABSTRACT FROM AUTHOR]