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"Cao, Yu-Tian"
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Airfoil response to periodic vertical and longitudinal gusts
Gust response has consistently been a concern in engineering. Critical theories have been proposed in the past to predict the unsteady lift response of an airfoil experiencing vertical gusts by Atassi, and longitudinal gusts by Greenberg. However, their applicability for an airfoil with non-zero angles of attack still needs clarification. Thus, force measurements are conducted to examine these theories’ validity and quasi-steady corrections are applied to compensate potential disparities between the idealised and real flow conditions. Velocity measurements are performed to scrutinise the effect of gusts on the flow around the airfoil, and subsequently to reveal the underlying mechanism governing the airfoil's response to gust-induced perturbations. In the study, two pitching vanes are arranged upstream to generate periodic vertical and longitudinal gusts, whereas a downstream airfoil with angles of attack of 0–12° is subjected to two gust types. It is found that Greenberg's theory demonstrates superior predictive capability in pre-stall regimes, with the potential for its effectiveness to be expanded to post-stall regimes through theoretical refinements. In contrast, Atassi's theory exhibits significant deviations from experimental outcomes across the measured angles of attack. Nevertheless, a modified version of the theory aligns better with experimental results at small angles of attack, whereas substantial discrepancies persist as the angle of attack increases. In the pre-stall regime, the aerodynamic response of the airfoil to vertical gusts displays a linear correlation with the flow angle near the leading edge. In the post-stall regime, the vertical gust induces dynamic stall of the airfoil. The flow angle has an essential effect on the lift coefficient but it alone is inadequate to dictate the trend of the lift coefficient. The vorticity statistics show that negative vortex circulation strongly correlates with the lift coefficient. Thus, further correction of the theory or a new vortex model can be expected to predict the lift variation.
Journal Article
Sex- and reproductive status-specific relationships between body composition and non-alcoholic fatty liver disease
Background
Sex and reproductive status differences exist in both non-alcoholic fatty liver disease (NAFLD) and body composition. Our purpose was to investigate the relationship between body composition and the severity of liver steatosis and fibrosis in NAFLD in different sex and reproductive status populations.
Methods
This cross-sectional study included 880 patients (355 men, 417 pre-menopausal women, 108 post-menopausal women). Liver steatosis and fibrosis and body composition data were measured using FibroScan and a bioelectrical impedance body composition analyzer (BIA), respectively, and the following parameters were obtained: liver stiffness measurement (LSM), controlled attenuation parameter (CAP), waist circumference (WC), body mass index (BMI), percent body fat (PBF), visceral fat area (VFA), appendicular skeletal muscle mass (ASM), appendicular skeletal muscle mass index (ASMI), fat mass (FM), fat free mass (FFM), and FFM to FM ratio (FFM/FM). Multiple ordinal logistic regression (MOLR) was used to analyze the independent correlation between body composition indicators and liver steatosis grade and fibrosis stage in different sex and menopausal status populations.
Results
Men had higher WC, ASM, ASMI, FFM, and FFM/FM than pre- or post-menopausal women, while pre-menopausal women had higher PBF, VFA, and FM than the other two groups (p < 0.001). Besides, men had greater CAP and LSM values (p < 0.001). For MOLR, after adjusting for confounding factors, WC (OR, 1.07; 95% CI, 1.02–1.12; P = 0.011) and FFM/FM (OR, 0.52; 95% CI, 0.31–0.89; P = 0.017) in men and visceral obesity (OR, 4.16; 95% CI, 1.09–15.90; P = 0.037) in post-menopausal women were independently associated with liver steatosis grade. WC and visceral obesity were independently associated with liver fibrosis stage in men (OR, 1.05; 95% CI, 1.01–1.09, P = 0.013; OR, 3.92; 95% CI, 1.97–7.81; P < 0.001, respectively).
Conclusions
Increased WC and low FFM/FM in men and visceral obesity in post-menopausal women were independent correlates of more severe liver steatosis. In addition, increased WC and visceral obesity were independent correlates of worse liver fibrosis in men. These data support the sex- and reproductive status-specific management of NAFLD.
Journal Article
Platelet abnormalities in autoimmune thyroid diseases: A systematic review and meta-analysis
Some degree of platelet index abnormality has been found clinically in the autoimmune thyroid disease (AITD), but the findings are not uniform.
The PubMed, Web of Science, Cochrane Library, and Embase databases were searched for relevant articles published up to August 16th, 2022, with no restrictions on the language of the articles. Reference lists of eligible articles were also searched. A random effect model was used to pool the standardized mean difference (SMD) and 95% confidence interval (95% CI) of platelet count (PLT), mean platelet volume (MPV), and platelet distribution width (PDW) between AITD patients and healthy controls, and subgroup analyses were performed.
A total of 19 articles with 6173 people (3824 AITD patients and 2349 healthy people) were included in the meta-analysis. The results showed that PLT and MPV values were significantly increased in AITD patients when compared with healthy people (SMD: 0.164, 95% CI: 0.044 to 0.285; SMD: 0.256, 95% CI: 0.013 to 0.500), while no significant difference was found in PDW between the AITD group and the control group (SMD: 0.060, 95% CI: -0.164 to 0.284). Subgroup analysis according to disease type and thyroid function revealed that for PLT, this difference was only found in the Hashimoto's thyroiditis (HT) and hypothyroid groups, but not in the Graves' disease (GD) and hyperthyroid groups. For MPV, the results were the opposite of those for PLT: MPV was significantly higher in the GD, hyperthyroid, and euthyroid groups than in the control group, but not in the HT and hypothyroid groups. Sensitivity analysis showed that the stability of the pooled MPV was not good. No publication bias was found.
PLT and MPV are significantly elevated in patients with AITD, with PLT being more significantly elevated in HT and hypothyroidism, and MPV being more significantly increased in GD and hyperthyroidism. Appropriate clinical attention can be paid to the thyroid function of patients when abnormal platelet indices are found, and conversely, the consequences of abnormal platelet parameters such as elevated MPV lead to an increased occurrence of cardiovascular events, which should also be addressed in the AITD population.
https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42022341823.
Journal Article
Sea-Surface Target Enhanced Detection Based on Attentional Multi-Pixel Fusion
Maritime target recognition and image perception enhancement are gradually being promoted and applied in ocean engineering. This paper proposes the attentional multi-pixel fusion (AMF) algorithm for the intelligent navigation of unmanned surface vessels (USVs). The algorithm preprocesses the image pixel matrix in blocks, computes the mapping between regional and full-pixel matrices, and adaptively equalizes the mapping weights via a Gaussian-fuzzy matrix. This approach guarantees the preservation of the target contour and texture information. Compared with five classic enhancement algorithms, the AMF algorithm improves the peak signal-to-noise ratio (PSNR) and structural similarity index (SSIM). Experimental validation via YOLOv8 for maritime target detection demonstrates 2.1% and 2.4% improvements in the evaluation indices over training on 4000 original images, with shorter training times and lower confusion rates. In maritime target ranging, the AMF algorithm, coupled with the ISR method, exhibits the lowest improved stereo ranging mean absolute error and standard deviation values and higher similarity between the regional and full-pixel matrices. In summary, the AMF algorithm excels in target detection and ranging, offering promising applications in ocean engineering, such as marine resource exploitation, path planning, and intelligent collaboration among unmanned vessels.
Journal Article
The Correlation Between Olfactory Test and Hippocampal Volume in Alzheimer's Disease and Mild Cognitive Impairment Patients: A Meta-Analysis
Background: Previous studies have reported that olfactory identification deficits may be the earliest clinical features of Alzheimer's disease (AD). However, the association between odor identification and hippocampal atrophy remains unclear. Objective: This meta-analysis quantified the correlation between odor identification test scores and hippocampal volume in AD. Method: A search of the PUBMED, EMBASE, and WEB OF SCIENCE databases was conducted from January 2003 to June 2020 on studies with reported correlation coefficients between olfactory identification score and hippocampal volume in patients with amnestic AD or mild cognitive impairment (MCI). The quality of the studies was assessed using the Newcastle-Ottawa quality assessment scale (NOS). Pooled r- values were combined and computed in R studio. Results: Seven of 627 original studies on AD/MCI using an olfactory identification test ( n = 902) were included. A positive correlation was found between hippocampal volume and olfactory test scores ( r = 0.3392, 95% CI: 0.2335–0.4370). Moderator analysis showed that AD and MCI patients were more profoundly correlated than normal controls (AD: r = 0.3959, 95% CI: 0.2605–0.5160; MCI: r = 0.3691, 95% CI: 0.1841–0.5288; NC: r = 0.1305, 95% CI: −0.0447–0.2980). Age difference and patient type were the main sources of heterogeneity in this analysis. Conclusion: The correlation appears to be more predominant in the cognitive disorder group (including MCI and AD) than in the non-cognitive disorder group. Age is an independent factor that affects the severity of the correlation during disease progression. The mildness of the correlation suggests that olfactory tests may be more accurate when combined with other non-invasive examinations for early detection. Systematic Review Registration: https://inplasy.com/ , identifier INPLASY202140088.
Journal Article
Corrigendum: Platelet abnormalities in autoimmune thyroid diseases: A systematic review and meta-analysis
[This corrects the article DOI: 10.3389/fimmu.2022.1089469.].
Journal Article
A Comparative Study of Ionospheric Response to Solar Flares at Earth, Venus, and Mars
It has been widely recognized that the ionosphere of the terrestrial planet responds greatly to the enhanced X-ray and extreme ultraviolet radiation during solar flares. However, little attention has been paid to the comparative study of the ionospheric response between different Earth-like planets. In this work, we investigate the responses of the ionospheres of Earth, Venus, and Mars to the 2017 September 6 solar flares, with self-consistent planetary ionospheric models. The result shows that the electron density increases significantly in the relatively low ionosphere region, and its maximum relative change displays profound differences between planets. The ion temperatures at Earth and Venus share a similar response to flares, but differ from those at Mars, which relates to the background atmospheric conditions. For the electron temperature response to the X9.3 flare, at Earth it increases with a maximum magnitude of 250 K, in contrast to the decrease of ∼45 K at Venus and ∼40 K at Mars. The vertical plasma velocity at all three planets exhibits enhancement during solar flares. As a result, the upward flux increases by 2.16 × 1012 m−2 s−1 at 800 km of Earth, 3.79 × 1010 m−2 s−1, and 8.45 × 109 m−2 s−1 at 400 km of Venus and Mars. This is the first self-consistent simulation of the flare-induced enhancement of upward plasma flow at Venus and Mars.
Journal Article
Xietu Hemu Prescription Improves Metabolic Dysfunction-Associated Steatotic Liver Disease: A Real-World Cohort Study
This study aims to evaluate the efficacy of the Xietu Hemu prescription (XHP) in improving metabolic dysfunction-associated steatotic liver disease (MASLD) through a Real World Study approach.
This was a single-center, prospective, real-world cohort study of 262 patients with MASLD who met the inclusion and exclusion criteria from November 2021 to November 2023 at Jiangsu Provincial Hospital of Traditional Chinese Medicine. The exposure of this study was who took the XHP. We assessed the efficacy of the XHP on MASLD by comparing FibroScan parameters, body composition indicators, and liver serological indicators. The XHP was then evaluated for MASLD by inverse probability of treatment weighting (IPTW) as well as log-binomial analysis.
We ended up collecting the exposure cohort (n=163) and the referent cohort (n=99). Patients were categorized into an exposure cohort (n=163, XHP + basic treatment) subdivided by treatment duration: 4 weeks (n=28), 8 weeks (n=60), 12 weeks (n=51), and ≥16 weeks (n=24), and a referent cohort (n=99, basic treatment alone). The results showed significant improvements in Liver stiffness measurement (LSM), controlled attenuation parameter (CAP), body mass index (BMI), waist-to-hip ratio (WHR), visceral fat area (VFA), the fatty liver index (FLI), and FibroScan-AST (FAST) in the exposure cohort after treatment compared to before treatment. After controlling confounding by IPTW, log-binomial analysis revealed that XHP administration was significantly more effective for MASLD in the exposure cohort than in the referent cohort (weighted risk ratio=2.99, 95% CI=1.86 to 4.89, p<0.001). Subgroup analyses revealed a significantly greater efficacy of the XHP in the exposure cohort compared to the MASLD referent cohort, across various durations and dosages of XHP and varying degrees of hepatic steatosis and fibrosis. No serious adverse events occurred; occasional mild gastrointestinal reactions were self-limiting.
The results of our study suggest that XHP has a significant treatment effect on MASLD, which hopes to complement the current lack of treatment for MASLD.
Journal Article
Culture and Social Transformations in Reform Era China
Leading scholars examine the interplay between the ideological reorientation and radical social changes in contemporary China in terms of the interpretation, appropriation and mobilization of three major cultural resources (traditional, May Fourth, and socialist) by various social groups.
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