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Purpose: This study aimed to evaluate the microbial contamination level and its influencing factors of rigid gas permeable (RGP) trial lenses and lens cases in China.Materials and Methods: A total ...

The early fault characteristics of rolling bearing are weak, and the background noise is so strong that it is difficult to diagnose. In order to solve the above problems, an early fault feature extraction method for rolling bearings based on variational mode decomposition and random decrement technique was proposed. The variational mode decomposition was used to decompose the collected vibration signals, and the component with the larger correlation coefficient was selected as the fault component. Then the fault component was processed by random decrement technology, and the Hilbert envelope spectrum of the fault component was made. According to the proposed method, the early fault characteristic of outer ring of rolling bearing was extracted. Compared with the method based on EMD, the proposed method is more effective in extracting the early fault characteristics of rolling bearings.

This study is to explore controllable preparation of poly (lactic-co-glycolic acid) (PLGA) microcapsules to load 2-[[(4-phenoxyphenyl)sulfonyl]methyl]-thiirane (SB-3CT) for traumatic brain injury (TBI) pharmacological therapy. Capillary-based microfluidic method was proposed to prepare SB-3CT loaded PLGA microcapsules. Drug loading and release behavior of the corresponding PLGA microcapsules were evaluated and correlated with their degradation profile. The obtained PLGA microcapsules had a golf-featured morphology and high mono-dispersion. Precise control on the size and size distribution of the microcapsules could be achieved by varying the geometry of the capillary device and operation parameters to yield uniform and reproducible PLGA microcapsules in the range of 35–65 µm. A high drug encapsulation efficiency of 99% within the obtained PLGA microcapsules with a releasing duration of around 50 d was ensured. Pharmacological therapy of TBI was tried by local injection of PLGA-SB-3CT suspension in rats at the trauma site after TBI. The protection on brain tissue upon administration was demonstrated by accelerated behavioral recovery (beam balance and beam walk latencies, and spatial memory ability) and reduction in the neuronal cell apoptosis in CA2 and hilus hippocampus as well as the injury cortical region. Hence, PLGA-SB-3CT could serve as a promising pharmaco-therapeutic option for TBI treatment.

Osteosarcoma (OS) is the most common primary pediatric bone tumor lethal to children and adolescents. Chemotherapeutic agents such as cisplatin are not effective for OS because of their poor accessibility to this cancer and severe systemic toxicity. In this study, a lipophilic platinum(II) complex bearing a bisphosphonate bone-targeting moiety, cis-[PtL(NH

Remote manipulation of a robot without assistance in an unstructured environment is a challenging task for operators. In this paper, a novel methodology for haptic constraints in a point cloud augmented virtual reality environment is proposed to address this human operation limitation. The proposed method generates haptic constraints in real time for an unstructured environment, including regional constraints and guidance constraints. A modified implicit surface method is applied for regional constraint generation for the entire point cloud. Additionally, the isosurface derived from the implicit surface is proposed for real-time three-dimensional artificial force field estimation. For guidance constraint generation, a new incremental prediction and local artificial force field generation method based on the modified sigmoid model is proposed in an unstructured point cloud virtual reality environment. With the generated haptic constraints, the operator can control the robot to realize obstacle avoidance and easily reach the target tasks. System evaluation is conducted, and the result demonstrates the effectiveness of the proposed method. In addition, a 10-participant study with users who control the robot to three specific targets shows that the system can enhance human operation efficiency and reduce time costs by at least 59% compared with no-haptic-constraint operations. Additionally, the designed questionnaire also demonstrates that the proposed methodology can reduce the workload during human operations.

In this paper, we mainly consider a class of free boundary problems of reaction-diffusion equations with nonlocal diffusion coefficient. By the well-known contraction mapping theorem, the uniqueness and existence of solutions are established for the local time t > 0 . Secondly, we give some sufficient conditions for vanishing phenomenon and spreading phenomenon, respectively. Further, we prove a spreading-vanishing dichotomy for this model. Finally, we obtain the asymptotic spreading speed when spreading happens.

Sea level change is not uniform across the oceans and high-resolution sea level trend (SLT) models reveal that the rate of sea level change differs between different waters. In this study, we developed a new method for obtaining a high-resolution, 1′×1′-grid SLT model, using the time-varying mean sea surface (MSS) of several MSSs calculated from averaged multi-satellite-derived sea surface heights (TOPEX/Poseidon, Jason-1/2/3, ERS-1/2, Envisat, GFO, Cryosat-2, SARAL/AltiKa, Sentinel-3A, HY-2A) over different periods. We applied this model to estimate the mean sea level change in the China seas and their adjacent ocean (0°–41°N, 100°–140°E). This new model revealed the patterning of sea level change within the study region in detail, and detected a sea level change dipole south of Japan. A zonal SLT pattern was identified in three regions: the region of the North Pacific Subtropical Counter Current (an eastward current located in the band of 19.5°–22.5°N, populated with eddies), and the areas east of Taiwan and east of Luzon Island. Moreover, the rate of sea level rise in the offshore zone was found to be ~ 0.67 mm/yr (20%) higher than that in the open ocean. This finding has important implications for coastal protection.

The pendular spectra of linear ( H C C C N ) n ( n = 1 − 3 ) molecules at several rotational temperatures under a certain range of electric field strength E are calculated using the finite element matrix diagonalization method. In addition, the normalized “ Q -branch” intensity ( I Q ) and the gradient ( K E ) of I Q under corresponding conditions are investigated. Based on the results, the range and sensitivity of measuring the electric field strength with linear ( H C C C N ) n ( n = 1 − 3 ) molecules are analyzed. A scheme to measure electric field strength based on ( H C C C N ) n ( n = 1 − 3 ) with high sensitivity is proposed and the spatial resolution is also discussed. The feasibility of measuring the electric field strength of the electrostatic Stark decelerator based on a pendular spectrum is studied.

Both noncontrast and contrast-enhanced approaches to gated thoracic magnetic resonance angiography (MRA) for aortic root evaluation have been reported at 3T. We compare qualitative and quantitative image quality measures for the two approaches, and assess the reproducibility of standard aortic measurements. Respiratory and cardiac gated MRA of the chest was performed at 3T in 45 patients: 23 after administration of iron-based blood pool contrast, and 22 without contrast. Image quality was assessed with a 5-point Likert scale, vessel lumen-to-muscle contrast ratios, and vessel wall sharpness. Two reviewers measured the ascending aorta diameter and valve annulus area. Interrater agreement was assessed using Bland-Altman plots and coefficient of variation (CV). Qualitative image quality was better with blood pool contrast in all principal vessels of the chest (mean Likert of 4.20 ± 0.79 vs. 2.60 ± 0.77, p

Osteosarcoma is the most common malignant bone tumor primarily affecting adolescents. Targeted platinum(II) complexes are promising candidates for overcoming the general toxicity of conventional platinum anticancer drugs. In this study four dinuclear platinum(II) complexes, {[cis-Pt(NH3 )2 Cl]2 (PD)} (NO3 )2 (1), {[cis-Pt(NH3 )2 Cl]2 (PDBP)} (NO3 )2 (2), {[cis-Pt(DACH)Cl]2 (PD)} (NO3 )2 (3), and {[cis-Pt(DACH)Cl]2 (PDBP)} (NO3 )2 (4) [PD=5,5'-carbonylbis(2-(2-(pyridin-2-yl)ethyl)isoindoline-1,3-dione), PDBP=tetraethyl (((bis(1,3-dioxo-2-(2-(pyridin-2-yl)ethyl)isoindolin-5-yl)methylene)amino) methylene)bis(phosphonate), DACH=1,2-diaminocyclohexane)], were designed and synthesized. The complexes were fully characterized by 1 H, 13 C, 195 Pt or 31 P NMR spectroscopy and HR-MS. ICP-MS studies showed that considerable amounts of Pt accumulate in U2OS osteosarcoma cells. The interactions of the complexes with calf thymus DNA and plasmid pUC19 DNA were investigated using CD and gel electrophoresis, which indicated that the complexes can react with DNA. The in vitro cytotoxicity showed that 2 is the most potent complex towards U2OS cells. The cellular inhibition mode was examined by flow cytometry. Complex 2 kills U2OS cells predominately through an apoptotic pathway and arrests the cell cycle mainly in the G2 or M phase. The results demonstrate that dinuclear platinum(II) complexes with bone-targeting groups could be anticancer agents for osteosarcoma.

SISR (Single image super-resolution) has always been a key problem in image processing field. In recent years, deep learning has been successfully used to SISR reconstruction. However, most of the previous deep learning methods use L2 norm based on pixel pairs as loss function, which results in a high peak signal-to-noise ratio (PSNR) value, but the perception quality has not been improved. When using Generative Adversarial Network (GAN), although it has good perception quality, PSNR is lower. So we’ll generate realistic results when both of them are used well. The image quality evaluation (IQA) network is to evaluate the image quality, so as to obtain good PSNR value and perception quality. In this paper, we use image quality assessment network to guide the SISR reconstruction network. Besides that, our proposed Super-resolution reconstruction of single image method is composed of several our given cross-attention units (CA) and is trained iteratively. Experimental results demonstrate that our method in qualitative and quantitative is better than others.

The Super-Resolution Generative Adversarial Network (SRGAN) is a seminal work that is capable of generating more realistic texture in semantics and style during single image super-resolution. However, Since the loss function adopts L2 norm based on pixel points, the hallucinated details are often accompanied with unpleasant artifacts even false pixels. Our model adjusts generative loss to L1 norm, and perceptual loss is still based on L2 norm. L1 cost function can reduce the coefficients of some features to zero, thus indirectly realizing the selection of features according to the perceptual loss, and obtaining more real texture features. The combination of these two loss functions ensures that the reconstructed results of the model are very close to the target image in terms of spatial features, high-level abstract features and semantic features, overall sensory and image quality. The generating network of our model is based on dense residual structure, and the dense connection of residual-in-residual is used to implement fast and accurate learning of high frequency features of images. The adversarial network is based on the structure of discriminators in DCGAN and WGAN. Experimental results show that subjective quality we reconstructed is much higher than SRGAN.

In the research of the bionics for manta rays, it is an important way to realize the pectoral fin movement through mechanical structure. This paper proposed a new type of bionic manta ray robot based on the linkage mechanism. After three-dimensional modeling, the overall structure of the robot was built. The torso of the robot seals the controller, sensor and power supply, and is controlled by the host computer through the signal cable. Its actuator consists of waterproof motors, a multi-level link, and a flexible fin surface. Then the kinematics of the linkage mechanism is analyzed. Finally, the feasible overall design scheme is determined and the prototype is developed. The underwater test of the bionic robot verified that the trajectory of the bionic robot is consistent with the fluttering shape of the manta ray. The prototype has good underwater performance, smooth and quiet movement, and can adapt to the working environment of deeper waters.

Coastal acoustic tomography can perform a realtime field observation, and can be an important supplement to the Marine Ranch Observation. In this paper, a short range experiment has been conducted in ZhaiRuo Island, ZhouShan on January 20,2019. Four acoustic stations sent signals to each other to obtain the travel time of the signal between stations. ADCP and CTD were used to collect reference data. The horizontal velocity fields are mapped by inversion. The range-average currents calculated by inversion and travel time difference are close, and the inversion results are almost the same as the velocities obtained by ADCP. Vloume transports are also proved to reach balance by calculating flow rates of upper 2m crossing perpendicularly to the peripheral paths. Experiments show the feasibility of the coastal acoustic tomography to observe small area.

Cerebrovascular disease is a major source of mortality that commonly requires neurosurgical intervention. MR imaging is the preferred technique for imaging cerebrovascular structures, as well as regions of pathology that include microbleeds and ischemia. Advanced MR imaging sequences such as time-of-flight, susceptibility-weighted imaging, and 3D T2-weighted sequences have demonstrated excellent depiction of arterial and venous structures with and without contrast administration. While the advantages of 3T compared with 1.5T have been described, the role of ultra-high-field (7T) MR imaging in neurovascular imaging remains poorly understood. In the present review, we examine emerging neurosurgical applications of 7T MR imaging in vascular imaging of diverse conditions and discuss current limitations and future directions for this technique.

The current study, inspired by the immunosuppressive property of rapamycin (Rapa) and the benefit of microspheres both as drug delivery system and cell carriers, was designed to develop an efficient Rapa delivery system with tunable controllability to facilitate its local administration. A capillary-based two-phase microfluidic device was designed to prepare monodisperse poly(lactide-co-glycolide) (PLGA) microspheres to load Rapa (PLGA-Rapa-M). The physical and chemical properties of PLGA-Rapa-M were characterized, and the Rapa loading capacity and release profile were explored. Chondrocytes were chosen as a cell model to evaluate the adhesion and proliferation on these microspheres. Controllability over the microsphere properties was illustrated. The PLGA-Rapa-M is averagely 63.91 μm in size with a narrow size distribution and a CV of 2.44%. The encapsulation efficiency of Rapa within microspheres via the current microfluidics was around 98%, and Rapa loading could be easily varied with a maximum value of ∼20%. The PLGA-Rapa-M has a sustained Rapa release duration of ∼3 months. These microspheres could not only successfully be used for Rapa sustained release but also as cell carriers for cell therapy since they can support the attachment/proliferation of chondrocytes. Hence, improved therapeutic index could be expected by using the current developed Rapa-release system.

Intraluminal thrombus (ILT) is present in the majority of abdominal aortic aneurysms (AAA) of a size warranting consideration for surgical or endovascular intervention. The rupture risk of AAAs is thought to be related to the balance of vessel wall strength and the mechanical stress caused by systemic blood pressure. Previous finite element analyses of AAAs have shown that ILT can reduce and homogenize aneurysm wall stress. These works have largely considered ILT to be homogeneous in mechanical character or have idealized a stiffness distribution through the thrombus thickness. In this work, we use magnetic resonance imaging (MRI) to delineate the heterogeneous composition of ILT in 7 AAAs and perform patient–specific finite element analysis under multiple conditions of ILT layer stiffness disparity. We find that explicit incorporation of ILT heterogeneity in the finite element analysis is unlikely to substantially alter major stress analysis predictions regarding aneurysm rupture risk in comparison to models assuming a homogenous thrombus, provided that the maximal ILT stiffness is the same between models. Our results also show that under a homogeneous ILT assumption, the choice of ILT stiffness from values common in the literature can result in significantly larger variations in stress predictions compared to the effects of thrombus heterogeneity.

To evaluate and compare wall enhancement patterns in saccular and fusiform intracranial aneurysms using high-resolution black-blood MRI at 7 T. Thirty-one patients with 32 unruptured intracranial aneurysms (21 saccular and 11 fusiform) underwent 7-T black-blood MRI. Aneurysm wall enhancement (AWE) was categorized as follows: no wall enhancement (NWE), focal wall enhancement (FWE), and uniform wall enhancement (UWE). The degree of enhancement was scored as follows: 0 (no enhancement), 1 (signal intensity (SI) of the aneurysm wall less than that of the pituitary infundibulum), and 2 (equal to that of the pituitary infundibulum). The chi-squared test was used to compare the AWE pattern and degree between saccular and fusiform aneurysms. In saccular aneurysms, 12/21 (57%) enhanced. Of these, 9 showed FWE (5 grade 1 and 4 grade 2), and 3 showed UWE (2 grade 1 and 1 grade 2). In fusiform aneurysms, 11/11 (100%) enhanced. Of these, 1 showed FWE and 10 showed UWE. All fusiform aneurysms had grade-2 enhancement. Fusiform aneurysms had more extensive and higher SI AWE than saccular aneurysms (p

Table S1. Qualitative and quantitative image quality assessment of DANTE-SPACE and CS-DANTE-SPACE. (Reader 2). (DOCX 15 kb)

BACKGROUND: Intraluminal thrombus (ILT) signal intensity on MRI has been studied as a potential marker of abdominal aortic aneurysm (AAA) progression. PURPOSE: 1) To characterize the relationship between ILT signal intensity and AAA diameter; 2) to evaluate ILT change over time; and 3) to assess the relationship between ILT features and AAA growth. STUDY TYPE: Prospective. SUBJECTS: Eighty AAA patients were imaged, and a subset (n = 41) were followed with repeated MRI for 16 ± 9 months. FIELD STRENGTH/SEQUENCE: 3D black-blood fast-spin-echo sequence at 3 T. ASSESSMENT: ILT was designated as “bright” if the signal was greater than 1.2 times that of adjacent psoas muscle. AAAs were divided into three groups based on ILT: Type 1: bright ILT; Type 2: isointense ILT; Type 3: no ILT. During follow-up, an active ILT change was defined as new ILT formation or an increase in ILT signal intensity to bright; stable ILT was defined as no change in ILT type or ILT became isointense from bright previously. STATISTICAL TESTS: Shapiro-Wilk test; Mann-Whitney U-test; Fisher’s exact test; Kruskal-Wallis test; Spearman’s r; intraclass correlation coefficient (ICC), Cohen’s kappa. RESULTS: AAAs with Type 1 ILT were larger than those with Types 2 and 3 ILT (5.1 ± 1.1 cm, 4.4 ± 0.9 cm, 4.2 ± 0.8 cm, P = 0.008). The growth rate of AAAs with Type 1 ILT was significantly greater than that of AAAs with Types 2 and 3 ILT (2.6 ± 2.5, 0.6 ± 1.3, 1.5 ± 0.6 mm/year, P = 0.01). During follow-up, AAAs with active ILT changes had a 3-fold increased growth rate compared with AAAs with stable ILT (3.6 ± 3.0 mm/year vs. 1.2 ± 1.5 mm/year, P = 0.008). DATA CONCLUSION: AAAs with bright ILT are larger in diameter and grow faster. Active ILT change is associated with faster AAA growth. Black-blood MRI can characterize ILT features and monitor their change over time, which may provide new insights into AAA risk assessment.

Objective: To assess whether intracranial vessel wall (IVW) MRI luminal measurements are more accurate than non-contrast 3D-TOF-MRA measurements for intracranial atherosclerotic stenosis, relative to CTA. Methods: Consecutive patients with non-calcified intracranial atherosclerotic stenosis seen on CTA, who had non-contrast 3D-TOF-MRA and IVW performed between 1 January 2013 and 20 April 2014 were selected, and images with stenosis were pre-selected by a single independent rater. The pre-selected CTA, MRA, and IVW (T1-weighted) images were then reviewed by two independent raters blinded to the other measurements in random order. Measurements were made in a plane perpendicular to the lumen on each modality. MRA and IVW measurements were compared to CTA, to determine which more accurately matched the degree of stenosis. Results: 18 patients with 33 intracranial atherosclerotic stenoses were included. Relative to CTA, IVW had 40% less variance than MRA (p = .004). IVW had a significantly higher concordance correlation coefficient (CCC) relative to CTA than MRA (.87 vs .68, p = .002). IVW and MRA did not have significant bias relative to CTA, however, 8/33 lesions showed >20% overestimation of the degree of stenosis on MRA, compared to 1/33 for IVW. CCC between raters were 0.84 (95% CI 0.67–0.93) for CTA, 0.83 (0.67–0.93) for TOF-MRA, and 0.85 (0.71–0.94) for IVW. For stenosis >50% sensitivity was 82% for IVW and 64% for MRA, while specificity was 73% for both. Conclusion: IVW provides more accurate stenosis measurements than MRA when compared to CTA. Advances in knowledge: Considering higher stenosis measurement accuracy of IVW, it can be more reliably used for quantitative evaluation relative to MRA.

Non-contrast 3D black blood MRI is a promising tool for abdominal aortic aneurysm (AAA) surveillance, permitting accurate aneurysm diameter measurements needed for patient management.To evaluate whether automated AAA volume and diameter measurements obtained from computer-aided segmentation of non-contrast 3D black blood MRI are accurate, and whether they can supplant reference standard manual measurements from contrast-enhanced CT angiography (CTA).Thirty AAA patients (mean age, 71.9 ± 7.9 years) were recruited between 2014 and 2017. Participants underwent both non-contrast black blood MRI and CTA within 3 months of each other. Semi-automatic (computer-aided) MRI and CTA segmentations utilizing deformable registration methods were compared against manual segmentations of the same modality using the Dice similarity coefficient (DSC). AAA lumen and total aneurysm volumes and AAA maximum diameter, quantified automatically from these segmentations, were compared against manual measurements using Pearson correlation and Bland-Altman analyses. Finally, automated measurements from non-contrast 3D black blood MRI were evaluated against manual CTA measurements using the Wilcoxon test, Pearson correlation and Bland-Altman analyses.Semi-automatic segmentations had excellent agreement with manual segmentations (lumen DSC: 0.91 ± 0.03 and 0.94 ± 0.03; total aneurysm DSC: 0.92 ± 0.02 and 0.94 ± 0.03, for black blood MRI and CTA, respectively). Automated volume and maximum diameter measurements also had excellent correlation to their manual counterparts for both black blood MRI (volume: r = 0.99, P0.001; diameter: r = 0.97, P0.001) and CTA (volume: r = 0.99, P0.001; diameter: r = 0.97, P0.001). Compared to manual CTA measurements, bias and limits of agreement (LOA) for automated MRI measurements (lumen volume: 1.49, [-4.19 7.17] cmSemi-automatic segmentation of non-contrast 3D black blood MRI efficiently provides reproducible morphologic AAA assessment yielding accurate AAA diameters and volumes with no clinically relevant differences compared to either automatic or manual measurements based on CTA.

This paper presents a novel method for a visual-haptic aid teleoperation system (VHATS). The human operator sends commands to the remote manipulator using a haptic device while observing the virtual environment at the local site. The virtual environment also generates aiding force, which helps the human operator feeling the real touching force and drive the remote manipulator to avoid obstacles. In our system, high-resolution point cloud data of the remote environment are collected by a Kinect sensor. Then three-dimensional (3-D) graphic models are reconstructed at the master site. The environment information is transmitted to the local site to create and update the virtual models after the time delay. The feedback force is divided into two parts, guiding force and virtual contact force. The guiding force is derived from the Artificial Potential Field Method (APFM) for obstacles avoiding. The virtual contact force is based on the parameters of geometric and dynamic models. An adaptive Window-based Sliding Least-Squares Method (AW-SLSM) is adopted to update the parameters of the dynamic models on-line. At last, the experimental platform is established, while a moving, obstacle avoiding, target picking task is carried out and verified in the presence of a round-trip communication delay of 2 s.

Modifying the BODIPY fluorophore with a 4-aminostyryl group forms a NIR fluorescent Cu 2+ sensor with a large Stokes shift, high photostability and a high quantum yield. The in vivo Cu 2+ fluorescence imaging in live mice was realized for the first time with this sensor, profiting from its reduced self-absorption and minor photobleaching.

High resolution MRI of the intracranial vessel wall provides important insights in the assessment of intracranial vascular disease. This study aims to refine high resolution 3D MRI techniques for intracranial vessel wall imaging at both 3 and 7 T using customized flip angle train design, and to explore their comparative abilities. 11 patients with intracranial artery disease (four atherosclerotic plaques, six aneurysms and one reversible cerebral vasoconstriction syndrome) were imaged at 3 and 7 T with a 3D T 1-weighted fast-spin-echo sequence (SPACE) both pre and post Gd contrast injection. Wall to lumen contrast ratio (CRwall-lumen), contrast enhancement ratio (ER) and the sharpness of the vessel wall were quantified. Two experienced radiologists evaluated the image quality on a 0–5 scale. Both 3 and 7 T achieved good image quality with high resolution (nominal 0.5 mm isotropic) and whole brain coverage. The CRwall-lumen and the ER measurements were comparable (p > 0.05). The 7 T images were significantly sharper (sharpness: 2.69 ± 0.50 vs. 1.88 ± 0.53 mm−1, p

Superparamagnetic iron oxide nanoparticles (SPIONs) are potential vehicles for targeted drug delivery and viable contrast agents for magnetic resonance imaging (MRI). A PtIV prodrug (HSPt) derived from functionalization of cisplatin with hydroxyl and succinate is conjugated with a poly(ethylene glycol) (PEG)-modified SPION for cancer therapy and monitoring of therapeutic responses. The relaxivity of HSPt–PEG-SPIONs is larger than that of commercial contrast agent Feridex, and a tumor-selective negative contrast is observed in MRI in a magnetic field. HSPt–PEG-SPIONs can be dissociated and reduced into PtII species by glutathione (GSH). Instead of forming DNA–Pt crosslinks, the reduced product induces direct DNA single- or double-strand breaks, which is uncommon for Pt drugs. The cytotoxicity of HSPt–PEG-SPIONs is positively correlated with the GSH level of tumor cells, which is opposite to the scenario of current Pt drugs. HSPt–PEG-SPIONs are as cytotoxic as cisplatin against cancer cells but are almost nontoxic towards normal cells. Since the mechanism of action of the nanocomposite is different from the established paradigm for Pt drugs, it may become a special theranostic agent for cancer treatment.

Background There is a worldwide outbreak of coronavirus disease 2019 (COVID-19), at present, accumulative attention has been paid to COVID-19 due to its global prevalence. Acupuncture may play a beneficial role in patients who suffer from COVID-19. In China and East Asia, acupuncture has been widely used to treat diverse diseases for thousands of years, as an important method of treatment now, it plays an indispensable role in the treatment of respiratory diseases in China. This study is designed to determine the efficacy and safety of acupuncture in COVID-19. Methods We will search the following sources for the Randomized controlled trials (RCT): The Cochrane Library, PubMed, EMBASE, Web of Science, Chinese Biomedical Literature Database (CBM), Chinese National Knowledge Infrastructure Database (CNKI), Chinese Science, and the Wanfang Database. All the above databases will be searched from the available date of inception until the latest issue. No language or publication restriction will be used. Primary outcomes will include chest CT and nucleic acid detection of respiratory samples. Results The results will provide a high-quality synthesis of current evidence for researchers in this subject area. Conclusion The conclusion of our study will provide evidence to evaluate whether acupuncture is an effective treatments for patients suffering from COVID-19. Prospero registration number CRD42020180875.

Purpose This study aims to explore wall enhancement characteristics of vertebrobasilar nonsaccular aneurysms (VBNAs) and their relationship to clinical symptoms. Methods We retrospectively analyzed VBNAs in the high resolution MR vessel wall imaging (HR-VWI) databases at two institutions. The aneurysmal basic characteristics and wall enhancement characteristics, were evaluated by two radiologists. The aneurysmal basic characteristics were location, type, the maximal outer diameter (Dmax), T1 hyperintensity, and mural thrombus. The wall enhancement characteristics included the presence or absence of enhancement, enhancement distribution (concentric or eccentric), enhancement grades ( Results 34 VBNAs cases were included in the final analysis. Of the 34 cases, 18 cases (52.9%) presented VBNAs’ related symptoms. Aneurysmal characteristics associated with symptoms were transitional type (P = 0.015), Dmax (P Conclusion Wall enhancement correlates with symptomatic VBNAs. Dmax and enhancement ratio of aneurysmal wall are important indicators to instable status of symptomatic VBNAs.

Altimeter waveforms are usually contaminated due to nonmarine surfaces or inhomogeneous sea state conditions. The present work aimed to present how the singular spectrum analysis (SSA) can be used to reduce the noise level in Jason-1 altimeter waveforms to obtain SSA-denoised waveforms, improving the accuracy of a mean sea surface height (MSSH) model. Comparing the retracked sea surface heights (SSHs) by a 50% threshold retracker for the SSA-denoised waveforms with those for the raw waveforms, the results indicated that SSA allowed a noise reduction on Jason-1 waveforms, improving the accuracy of retracked SSHs. The MSSH model (called Model 1) over the South China Sea with a grid of 2&prime, &times, 2&prime, was established from the retracked SSHs of Jason-1 by the 50% threshold retracker for the SSA-denoised waveforms. Comparing Model 1 and Model 2 (established from the retracked SSHs by the 50% threshold retracker for the raw waveforms) with the CLS15 and DTU18 models in the South China Sea, it was found that the accuracy of Model 1 was higher than that of Model 2, which indicates that using SSA to reduce noise level in Jason-1 waveforms can effectively improve the accuracy of the MSSH model.

A new mean sea surface (MSS) model (named Shandong University of Science and Technology (2018) (SUST2018) MSS model) with a grid of 1′ × 1′ over China seas and its adjacent ocean (0°N~41°N, 100°E~140°E) is established and validated. The SUST2018 model established with the 19-year moving average method is based on 26-year multi-satellite altimeter data covering the time period 1992–2018. The new altimetry data of HaiYang-2A (HY-2A), Jason-3 and Sentinel-3A have been used in establishing the SUST2018 model. The process of the establishment of the MSS model also have been presented, including collinear adjustment of exact repeat mission (ERM) data, removal of the temporal oceanic variability of geodetic mission (GM) data, crossover adjustment and gridding. The reliability and accuracy of SUST2018 are validated by comparing with the CLS15 and DTU18 MSS models as well as satellite altimeter data. By comparing SUST2018 and SUST(all)2018 (established with the traditional average method), it can be found that the accuracy of SUST2018 is higher than that of SUST(all)2018, which indicates that the 19-year moving average method can effectively improve the accuracy of an MSS model.

Background Few studies directed at assessing the visualization of the walls of unruptured aneurysms have used higher-resolution 3D MRI vessel wall imaging. Prospective longitudinal studies are also needed to screen vessel wall changes in unruptured aneurysms. Purpose To compare the aneurysm wall visualization on pre- and post-3D isotropic T1 -weighted Sampling Perfection with Application-optimized Contrasts by using different flip angle Evolutions (SPACE) images and to explore whether there is a change in wall enhancement at follow up. Study type Prospective. Population Twenty-nine patients with a total of 35 unruptured intracranial aneurysms. Sequence 3D T1 -weighted pre- and postcontrast SPACE (0.5 mm isotropic) at 3.0T. Assessment The aneurysm wall visibility (0-5 scale) between pre- and postcontrast images as well as the wall enhancement (0-5 scale) between follow-up and baseline studies (6-30 months, average 12.7 months) were compared. Differences in wall visibility and enhancement were also investigated as a function of aneurysm diameter and location. Statistical test The Wilcoxon signed rank paired test was used to compare the wall visibility score between pre- and postcontrast SPACE images, as well as wall enhancement between follow-up and baseline. The Mann-Whitney and Kruskal-Wallis tests were used to investigate the enhancement difference between different diameters and locations. Results Postcontrast images had significantly higher wall visibility (P = 0.01). A wall enhancement score ≥2 was found in 71% of the aneurysms. Changes in levels of wall enhancement were found in 17% of the aneurysms at follow-up studies, but those changes were small. Wall visibility and enhancement scores of large aneurysms were significantly higher than small ones (P Data conclusion 3D T1 -weighted higher resolution SPACE can be used to assess changes in enhancement at follow-up studies. Contrast SPACE image provides better aneurysm wall visibility and improves visualization of the aneurysm wall. Level of evidence 2 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2019;50:193-200.

The aim of this study was to compare image quality of low tube voltage cerebral computed tomography angiography (CTA) reconstructed with knowledge-based iterative model reconstruction (IMR), filtered back projection (FBP), and hybrid iterative reconstruction (HIR). A total of 101 patients with suspected cerebrovascular diseases were enrolled and randomized into 2 groups, 100 kVp tube voltage (n = 53) and reduced tube voltage (80 kVp) (n = 48). Computed tomography data were reconstructed with IMR, FBP, and HIR algorithms. The image noise, vascular attenuation, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) were measured and calculated. Two blinded radiologists independently evaluated image quality based on diagnostic confidence on a 3-point scale. Quantitative and qualitative assessments were compared between different groups and reconstruction subgroups. Vascular attenuation was higher in the reduced tube voltage group than in 100-kVp tube voltage group, but showed no significant difference within each group. In both groups, the image noise, vascular SNR, and CNR were significantly improved by IMR as compared with FBP and HIR. Inter-group comparison indicated that IMR with reduced tube voltage showed better image quality with lower image noise and higher vascular SNR and CNR than FBP and HIR at 100 kVp, but slightly inferior to IMR at 100 kVp. IMR also yields the best qualitative image quality, and improves the diagnostic confidence of atherosclerosis and aneurysm. Compared with the standard 120-kVp protocol (1.86mSv), the radiation doses of 100 kVp (1.13mSv) and 80 kVp (0.56mSv) were 39% and 70% less, respectively. The quantitative and qualitative image quality obtained by IMR was superior to that obtained by FBP and HIR for low tube voltage cerebral CTA.

The paper reports a free-breathing black-blood CINE fast-spin echo (FSE) technique for measuring abdominal aortic wall motion. The free-breathing CINE FSE includes the following MR techniques: (1) variable-density sampling with fast iterative reconstruction; (2) inner-volume imaging; and (3) a blood-suppression preparation pulse. The proposed technique was evaluated in eight healthy subjects. The inner-volume imaging significantly reduced the intraluminal artifacts of respiratory motion (p = 0.015). The quantitative measurements were a diameter of 16.3 ± 2.8 mm and wall distensibility of 2.0 ± 0.4 mm (12.5 ± 3.4%) and 0.7 ± 0.3 mm (4.1 ± 1.0%) for the anterior and posterior walls, respectively. The cyclic cross-sectional distensibility was 35 ± 15% greater in the systolic phase than in the diastolic phase. In conclusion, we developed a feasible CINE FSE method to measure the motion of the abdominal aortic wall, which will enable clinical scientists to study the elasticity of the abdominal aorta.

Large sheaves, such as crosshead sheaves, are foundation parts in the heavy industry. Counter-roller spinning steel sheaves are utilized to replace traditional casting iron parts. Few studies exist on the groove shape of these spinning sheaves. Consequently, it is significant to explore the spinning groove shape variation rule and confirm the appropriate spinning parameters. Both experimental and numerical methods were utilized to study the groove shape variation of Q235 steel sheaves and their results were well matched. Spring-back phenomena were considered in this study. The groove depth was lower than the spinning depth and the last formed groove was the deepest. The former groove depth would be affected by the adjacent following spinning process. The single groove spinning result was linearly dependent on the multiple spinning groove depth. Certain equations were used to calculate the groove depth. The bottom&ndash, middle&ndash, top spinning sequence, which was better than other spinning sequences, should be used in the sheave spinning method. A sheave spinning process could be designed based on the study to obtain a fine groove shape.

Rationale and Objectives Aneurysm wall enhancement (AWE) on magnetic resonance vessel wall imaging has been proposed as an imaging marker of aneurysm wall inflammation and instability. We performed a systematic review and meta-analysis to summarize the association between AWE and aneurysm rupture. Materials and Methods We performed a comprehensive literature search of studies evaluating the association between AWE and aneurysm rupture. We abstracted the following study data: study design, patient demographics, aneurysm characteristics, MRI protocols, and AWE assessment. We performed meta-analysis using a random-effects model. Study heterogeneity was assessed by using the Cochrane Q and I2 statistic, and publication bias was examined by using the Begg–Mazumdar test. Results Five studies with 492 subjects met eligibility for systematic review. We found a significant positive overall association between AWE and aneurysm rupture, with an odds ratio (OR) of 34.26 (95% confidence interval [CI] 10.20–115.07, p Conclusion AWE on magnetic resonance vessel wall imaging is significantly and independently associated with aneurysm rupture and may become a promising imaging marker to predict aneurysm behavior and identify high-risk aneurysms.

The Industry 4.0 is regard as the fourth industrial revolution which is geared to the demand of customization products. As one kind of basic components in industry, the small complicated axisymmetric parts are usually low-volume customization products. So it is significant to explore their manufacturing process in the Industry 4.0 era. The production procedure of a representative 4 stages cone has been studied. First, requirements of customers are sent to the industrial internet. Then technology suppliers will design an appropriate forming process with the CAD (Computer-Aided Design), CAE (Computer-Aided Engineering), CAPP (Computer-Aided Process Planning), CAM (Computer-Aided Manufacturing) and other Industry 4.0 technologies. Finally, distributed smart factories will organize production and send target products to customers depending on the industrial internet. Based on this study, it can be seen that the metal spinning method is suitable for the small complicated axisymmetric parts producing in Industry 4.0. The remote customization manufacturing will be more popularize. Even, the CAD, CAE, CAPP and CAM method will play more important roles in manufacture with the help of industrial internet.

Aneurysm wall enhancement (AWE) on MRI has been considered an imaging marker to indicate active aneurysm inflammation, but no prospective studies have assessed the ability of AWE to predict rupture risk or growth. We aim to study the association of AWE with traditional risk factors and the estimated rupture risk. Seventy-seven patients (mean age, 58.4 ± 10.8 years; 57% female) with 88 asymptomatic intracranial saccular aneurysms underwent both 3-T high-resolution MRI and three-dimensional (3D) rotational digital subtraction angiography (DSA). Geometric and morphologic parameters were measured on DSA, and the degree of AWE on MRI was graded. One- and 5-year rupture risks of aneurysms were estimated using the UCAS and PHASES calculator. Parameters associated with AWE were analyzed using uni- and multivariate logistic regression. Non-internal carotid artery location (OR 3.4, 95% CI 1.6-7.1) and aneurysm size (OR 1.9, 95% CI 1.3-2.7) were independently associated with AWE (p < 0.05). Aneurysms with AWE had significantly higher estimated rupture risk (1 and 5 year, 1.9% and 5.8%) than aneurysms without AWE (0.5% and 2.1%) (p < 0.001). Stronger and larger areas of AWE were correlated with the aneurysm size, size ratio and estimated rupture risk (R2 ≥ 0.30) (p < 0.01). Prospective assessment of asymptomatic intracranial aneurysms with MRI suggests that AWE is associated with traditional risk factors and estimated short- and medium-term rupture risk. • AWE independently associates with aneurysm location and size. • Aneurysms with AWE have higher rupture risk than aneurysms without AWE. • Stronger and larger areas of AWE correlated with the aneurysm size, size ratio and rupture risk.

With different polarity responses, coumarin and 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene (BODIPY) were hybridised to construct polarity fluorescent sensors, CBDP and iso-CBDP, to overcome the disadvantages of solvatochromic sensors in ratiometric polarity sensing. Only CBDP displayed an emission ratio (ICou /IBDP , coumarin to BODIPY emissions) that increased with an exponential dependence on medium relative permittivity over a wide polarity range (ϵr

A highly stretchable hyaluronic acid (HA)/sodium alginate (SA) hydrogel was developed in this study based on an interpenetrating polymer network. HA/SA hydrogels were prepared by mixing two polysaccharides followed by covalent crosslinking via epoxy groups on HA molecules and ionic crosslinking via divalent ions on SA chains sequentially. The effect of HA/SA ratio on the pore size and distribution, swelling ratio, elongation and rheological properties as well as protein loading and release properties of HA/SA hydrogels was explored. Moreover, a surface modification method, layer-by-layer (LBL) assembly technique, was applied to modify the hydrogel to evaluate the hydrogel's tenability in varying biological performance. It was then shown that the hydrogels had the pore sizes ranging from 100 to 50 μm. With the increase in SA content of the resulting hydrogels, the pore size, swelling ratio, and storage modulus (G') and loss modulus (G″) of the hydrogel all decreased, whereas the in vitro bulk weight loss was fastened. Moreover, elongation at break (EB) value increased first, reached a peak value and then decreased, that is HA8/SA1 (HA:SA = 8:1) had the highest EB value of 417%. This hydrogel could retain 33.2% of the pre-loaded protein even after 72 h, which could be further attenuated when LBL was used to shell the hydrogel. The growth of fibroblasts on HA8/SA1 hydrogel gave preliminary assessment on its suitability as a cellular carrier, while the LBL modified HA8/SA1 hydrogel also favored the anchoring of keratinocytes, further enhancing its cell carrier role for tissue regeneration, especially skin engineering.

It is a challenging task for operators to interact with the remote environment without its geometric and dynamic knowledge during teleoperation. In this article, a novel system architecture for implementing the translational object modeling and correction during remote interaction is proposed to reconstruct the haptic interaction and predict the object motion at the local virtual reality–based teleoperation. First, a stress mutation analysis method is proposed for segmenting the translational object motion into static phase, critical phase, and sliding phase. And the static limiting friction is originally estimated in the teleoperation area. Meanwhile, mass-damper-spring model and adapted Karnopp friction model are adopted for dynamic modeling in each phase. Second, a novel adaptive forgetting factor recursive least square method is studied for high-accuracy parameter estimation. With the estimated model parameters, the motion of the translational object is predicted at the master side. Meanwhile, for model consistence between the real and virtual environments, a new correction strategy is used to adaptively update the environment model. According to the experimental results, the translational object can be accurately modeled in real time, and its motion at the master side can be predicted precisely and corrected promptly.

OBJECTIVE:Develop and optimize an accelerated, high-resolution (0.5mm isotropic) 3D black blood MRI technique to reduce scan time for whole-brain intracranial vessel wall imaging. MATERIALS AND METHODS:A 3D accelerated T1-weighted fast-spin-echo prototype sequence using compressed sensing (CS-SPACE) was developed at 3T. Both the acquisition [echo train length (ETL), under-sampling factor] and reconstruction parameters (regularization parameter, number of iterations) were first optimized in 5 healthy volunteers. Ten patients with a variety of intracranial vascular disease presentations (aneurysm, atherosclerosis, dissection, vasculitis) were imaged with SPACE and optimized CS-SPACE, pre and post Gd contrast. Lumen/wall area, wall-to-lumen contrast ratio (CR), enhancement ratio (ER), sharpness, and qualitative scores (1-4) by two radiologists were recorded. RESULTS:The optimized CS-SPACE protocol has ETL 60, 20% k-space under-sampling, 0.002 regularization factor with 20 iterations. In patient studies, CS-SPACE and conventional SPACE had comparable image scores both pre- (3.35±0.85 vs. 3.54±0.65, p=0.13) and post-contrast (3.72±0.58 vs. 3.53±0.57, p=0.15), but the CS-SPACE acquisition was 37% faster (6:48 vs. 10:50). CS-SPACE agreed with SPACE for lumen/wall area, ER measurements and sharpness, but marginally reduced the CR. CONCLUSION:In the evaluation of intracranial vascular disease, CS-SPACE provides a substantial reduction in scan time compared to conventional T1-weighted SPACE while maintaining good image quality.

OBJECTIVE. Ferumoxytol is increasingly reported as an alternative to gadolinium-based contrast agents for MR angiography (MRA), particularly for patients with renal failure. This article summarizes more than 3 years of clinical experience with ferumoxytol-enhanced MRA for a range of indications and anatomic regions. CONCLUSION. Ferumoxytol-enhanced MRA has many advantages including that it is safe for patients with renal failure and provides a lengthy plateau of vascular signal as a blood pool agent that allows longer navigated MRA sequences.

Multi-pass equal-channel angular pressing (EACP) was applied to produce ultrafine-grained (UFG) Cu-0.2wt%Mg alloy contact wire with high mechanical/electric performance, aim to overcome the catenary barrier of high-speed trains by maximizing the tension and improving the power delivery. Microstructure evolution and overall properties of the Cu-Mg alloy after different severe-plastic-deformation (SPD) routes were investigated by microscopic observation, tensile and electric tests. The results show that the Cu-Mg alloy after multi-pass ECAP at 473 K obtains ultrafine grains, higher strength and desired conductivity. More passes of ECAP leads to finer grains and higher strength, but increasing ECAP temperature significantly lower the strength increment of the UFG alloy. Grain refinement via continuous SPD processing can endow the Cu-Mg alloy superior strength and good conductivity characteristics, which are advantageous to high-speed electrification railway systems.

Epidemiological surveys have demonstrated that helminth infections are negatively related to atopic diseases, including asthma. Defining and characterising specific helminth molecules that have excellent immunomodulatory capacities as potential therapeutics for the treatment or prophylaxis of allergic manifestations are of great interest. AcCystatin, a cystatin protease inhibitor of Angiostrongylus cantonensis, is a homologue of other nematode cystatins with immunoregulatory properties. Here, we aim to determine the effects of AcCystatin on an ovalbumin/aluminium hydroxide (OVA/Al[OH]3)-induced rat model of asthma. Wistar rats were randomly divided into four groups, including a control group, an OVA/Al[OH]3-induced asthma group, a group receiving AcCystatin immunisation prior to OVA/Al[OH]3-induced asthma and a group receiving AcCystatin treatment after OVA/Al[OH]3-induced asthma. The numbers of eosinophils, basophils, neutrophils, lymphocytes and monocytes in the peripheral blood and of eosinophils in the bronchoalveolar lavage fluid (BALF) were counted for each animal. The expression levels of the cytokines interferon-γ, interleukin (IL) 4, IL-5, IL-6, IL-10, IL17A and tumour necrosis factor receptor-α in BALF, of OVA-specific immunoglobulin E in BALF and serum and of the chemokines eotaxin-1, eotaxin-2, eotaxin-3, MCP-1 and MCP-3 in lung tissue were measured. In addition, the degree of peribronchial and perivascular inflammation and the intensity of goblet cell metaplasia were qualitatively evaluated. The sensitised/challenged rats developed an extensive cell inflammatory response of the airways. AcCystatin administration significantly reduced the cellular infiltrate in the perivascular and peribronchial lung tissues and reduced both goblet mucous production and eosinophil infiltration. The rats that were treated with AcCystatin before or after sensitisation with OVA showed significant decreases in eotaxin-1, eotaxin-3 and MCP-1 expression in the lung tissue. The production of IL-4, IL-5, IL-6 and IL-17A and of OVA-specific IgE antibodies was also significantly reduced in AcCystatin-treated rats compared with untreated asthmatic rats. The AcCystatin treatment was associated with a significant increase in IL-10 levels. Our present findings provide the first demonstration that AcCystatin is an effective agent in the prevention and treatment of the airway inflammation associated with asthma.