Association of circulating omentin level and metabolic-associated fatty liver disease: a systematic review and meta-analysis

BackgroundMetabolic-associated fatty liver disease (MAFLD) is closely associated with omentin, a novel adipokine that plays a vital role in metabolic balance. The literature about the relationship between circulating omentin and MAFLD is conflicting. Therefore, this meta-analysis evaluated circulating omentin levels in patients with MAFLD compared with healthy controls to explore the role of omentin in MAFLD.MethodsThe literature search was performed up to April 8, 2022, using PubMed, Cochrane Library, EMBASE, CNKI, Wanfang, CBM, Clinical Trials Database and Grey Literature Database. This meta-analysis pooled the statistics in Stata and presented the overall results using the standardized mean difference (SMD) and 95% confidence interval (CI).ResultsTwelve studies with 1624 individuals (927 cases and 697 controls) were included, and all of them were case-control studies. In addition, ten of twelve included studies were conducted on Asian participants. Patients with MAFLD had significantly lower circulating omentin levels than healthy controls (SMD=-0.950 [-1.724, -0.177], P=0.016). Subgroup analysis and meta-regression demonstrated that fasting blood glucose (FBG) might be the source of heterogeneity and was inversely associated with omentin levels (coefficient=-0.538, P=0.009). No significant publication bias existed (P>0.05), and outcomes were robust in the sensitivity analysis.ConclusionLower circulating omentin levels were associated with MAFLD, and FBG might be the source of heterogeneity. Since Asian studies accounted for a significant portion of the meta-analysis, the conclusion might be more applicable to the Asian population. By investigating the relationship between omentin and MAFLD, this meta-analysis laid the foundation for the development of diagnostic biomarkers and treatment targets.Systematic review registrationhttps://www.crd.york.ac.uk/prospero/, identifier CRD42022316369

Evolution of hydrogen and helium co-implanted single-crystal silicon during annealing

H+H+ was implanted into single-crystal silicon with a dose of 1×1016/cm21×1016/cm2 and an energy of 30 KeV, and then He+He+ was implanted into the same sample with the same dose and an energy of 33 KeV. Both of the implantations were performed at room temperature. Subsequently, the samples were annealed in a temperature range from 200 to 450 °C450 °C for 1 h. Cross-sectional transmission electron microscopy, Rutherford backscattering spectrometry/channeling, elastic recoil detection, and high resolution x-ray diffraction were employed to characterize the strain, defects, and the distribution of H and He in the samples. The results showed that co-implantation of H and He decreases the total implantation dose, with which the surface could exfoliate during annealing. During annealing, the distribution of hydrogen did not change, but helium moved deeper and its distribution became sharper. At the same time, the maximum of the strain in the samples decreased a lot and also moved deeper. Furthermore, the defects introduced by ion implantation and annealing were characterized by slow positron annihilation spectroscopy, and two positron trap peaks were found. After annealing, the maximum of these two peaks decreased at the same time and their positions moved towards the surface. No bubbles or voids but cracks and platelets were observed by cross-sectional transmission electron microscopy. Finally, the relationship between the total implantation dose and the fraction of hydrogen in total implantation dose was calculated. © 2001 American Institute of Physics.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/70387/2/JAPIAU-90-8-3780-1.pd

Defect and strain in hydrogen and helium coimplanted single-crystal silicon

In this paper we studied the processes of blistering and exfoliation on the surface of crystal silicon, the evolution of defects/strains in the crystal silicon caused by hydrogen and helium coimplantation during annealing, and the formation of platelets and bubbles in the crystal. It is shown that H + and He + coimplantation produces a synergistic effect, which greatly decreases the total implantation dose, compared with either just H + or He + implantation. We also present the effect of coimplantation and analyse the different roles of H and He in the process of exfoliation during annealing. It seems that the essential role of hydrogen is to interact chemically with the defects in the silicon and create H-stabilized platelets, while the role of helium is to effuse into these platelets and exert a pressure on the inner surface of these platelets. The damage caused by coimplantation is lower than by hydrogen implantation (at the dose that exfoliation requires).Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/48907/2/d10102.pd

Comparison between the different implantation orders in H + and He + coimplantation

H + and He + were implanted into single crystals in different orders (H + first or He + first). Subsequently, the samples were annealed at different temperatures from 200 °C to 450 °C for 1 h. Cross sectional transmission electron microscopy, Rutherford backscattering spectrometry and channelling, elastic recoil detection were employed to characterize the defects and the distribution of H and He in the samples. Furthermore, the positron traps introduced by ion implantation and annealing were characterized by slow positron annihilation spectroscopy. Both orders in the coimplantation of H and He have the ability to decreases the total implantation dose after annealing. No bubbles or voids but cracks and platelets, were observed by cross sectional transmission electron microscopy. The different implantation orders affect the density of interstitial atoms and positron traps.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/48910/2/d10406.pd

Pose estimation-dependent identification method for field moth images using deep learning architecture

Due to the varieties of moth poses and cluttered background, traditional methods for automated identification of on-trap moths suffer problems of incomplete feature extraction and misidentification. A novel pose estimation-dependent automated identification method using deep learning architecture is proposed in this paper for on-trap field moth sample images. To deal with cluttered background and uneven illumination, two-level automated moth segmentation was created for separating moth sample images from each trap image. Moth pose was then estimated in terms of either top view or side view. Suitable combinations of texture, colour, shape and local features were extracted for further moth description. Finally, the improved pyramidal stacked de-noising auto-encoder (IpSDAE) architecture was proposed to build a deep neural network for moth identification. The experimental results on 762 field moth samples by 10-fold cross-validation achieved a good identification accuracy of 96.9%, and indicated that the deployment of the proposed pose estimation process is effective for automated moth identification

Lateral stability simulation and analysis for wheel loaders based on the steady-state margin angle

Wheel loaders are prone to lateral tilting accidents due to their complex working environment, variable structure frame and the large offset of the centroid position. The accidents may seriously threaten the driver's safety. This paper proposes a steady-state margin (SSM) angle as a new instability threat indicator to analyse lateral stability of wheel loaders. Firstly, the structural characteristics and the rollover process of a wheel loader are presented, and the SSM angle is defined. Secondly, on the assumption that the tyres are rigid, the calculation process of the SSM angle is described in detail, then the SSM angle of the XG953 wheel loader is computed. A virtual prototyping simulation was performed under the environment of ADAMS. The maximum relative error between the theoretical calculation and simulated result was 4.55%, within the permissible speed range. When changing the tyre parameters to normal tyre parameters, the relative error became larger. Finally, an indirect method is proposed to deal with the influence of tyres on the SSM angle and reduce the relative error

Effect of ultrasonic frequency on cavitation behavior, microstructure and mechanical properties of AZ80 magnesium alloy

In this paper, the effects of single-frequency ultrasonic treatment (SUT) and dual-frequency ultrasonic treatment (DUT) on the microstructure and mechanical properties of AZ80 magnesium alloy were investigated by numerical simulation and experimental research. Numerical simulation shows that the effective cavitation area of 15 kHz SUT is about twice that of 20 kHz, while the cavitation area of the 15 + 20 kHz DUT is larger than the sum of two SUT. The experimental results find that grains are refined after ultrasonic treatment, while the refinement effects of SUT and DUT are different. Under the same power condition, the refinement effect of 15 kHz is better than 20 kHz, but the DUT has higher efficiency than both SUT. The average grain size of untreated ingot is 174 mu m, which is reduced to 123 mu m, 99 mu m and 80 mu m after 20 kHz SUT, 15 kHz SUT and 15 + 20 kHz DUT, respectively. Therefore, applying DUT is more efficient in refining the grain size of the AZ80 magnesium alloy

Modelling of stable angle-based instability threat indicator for articulated off-road vehicles

This paper presents the modelling and simulation of a stable angle-based instability threat indicator for articulated off-road vehicles. First, a stable angle is represented by the vertical forces of four wheels and steering angle of an off-road articulated steer vehicle. Then a vehicle prototype model is built based on a specific wheel loader type and a tyre/terrain model. Finally, the prototype model and tyre/terrain model are imported to the multi-body dynamics analysis software-ADAMS to conduct a number of simulations using the stable angle-based instability threat indicator. Simulation results indicate that a stable angle of 80.5° is the threshold angle for lateral instability, and a stable angle of 90° is the threshold angle for longitudinal instability of this model. Compared with the traditional instability indicating methods for off-road vehicles, the proposed stable angle-based method is more efficient and can deal with both lateral and longitudinal instability of an articulated vehicle effectively. Copyright © 2014 Inderscience Enterprises Ltd

A Computer-Aided Modeling and Measurement System for Environmental Thermal Comfort Sensing

Predicted mean vote (PMV) is a well-known thermal comfort index with four environmental variables (air temperature, relative humidity, air velocity, and average radiation temperature) and two human factors (metabolic rate and clothing thermal resistance). This paper presents a novel computer-aided thermal comfort measurement system with PMV, which combined the advanced sensors with the virtual instrument technology. The system software is developed using the LabVIEW platform. The measured data can be transmitted to the server-computer in a data center and displayed on a web page through the Internet. The impact of the measurement error of each environmental variable on PMV is analyzed via MATLAB. The system tests were conducted under the certain environmental conditions and Monte Carlo method is deployed to analyze the PMV measurement uncertainty. The experimental results show the feasibility and effectiveness of the proposed system, and confirm that the measurement uncertainty of PMV is not a constant, and varies with the environment changes