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Background: Diabetic peripheral neuropathy (DPN) is the most prevalent complication of diabetes, and has been demonstrated to be independently associated with cardiovascular events and mortality. This aim of this study was to investigate the subclinical left ventricular (LV) myocardial dysfunction in type 2 diabetes mellitus (T2DM) patients with and without DPN. Methods: One hundred and thirty T2DM patients without DPN, 61 patients with DPN and 65 age and sex-matched controls who underwent cardiovascular magnetic resonance (CMR) imaging were included, all subjects had no symptoms of heart failure and LV ejection fraction ≥ 50%. LV myocardial non-infarct late gadolinium enhancement (LGE) was determined. LV global strains, including radial, circumferential and longitudinal peak strain (PS) and peak systolic and diastolic strain rates (PSSR and PDSR, respectively), were evaluated using CMR feature tracking and compared among the three groups. Multivariable linear regression analyses were performed to determine the independent factors of reduced LV global myocardial strains in T2DM patients. Results: The prevalence of non-infarct LGE was higher in patients with DPN than those without DPN (37.7% vs. 19.2%, p = 0.008). The LV radial and longitudinal PS (radial: 36.60 ± 7.24% vs. 33.57 ± 7.30% vs. 30.72 ± 8.68%; longitudinal: − 15.03 ± 2.52% vs. − 13.39 ± 2.48% vs. − 11.89 ± 3.02%), as well as longitudinal PDSR [0.89 (0.76, 1.05) 1/s vs. 0.80 (0.71, 0.93) 1/s vs. 0.77 (0.63, 0.87) 1/s] were decreased significantly from controls through T2DM patients without DPN to patients with DPN (all p < 0.001). LV radial and circumferential PDSR, as well as circumferential PS were reduced in both patient groups (all p < 0.05), but were not different between the two groups (all p > 0.05). Radial and longitudinal PSSR were decreased in patients with DPN (p = 0.006 and 0.003, respectively) but preserved in those without DPN (all p > 0.05). Multivariable linear regression analyses adjusting for confounders demonstrated that DPN was independently associated with LV radial and longitudinal PS (β = − 3.025 and 1.187, p = 0.014 and 0.003, respectively) and PDSR (β = 0.283 and − 0.086, p = 0.016 and 0.001, respectively), as well as radial PSSR (β = − 0.266, p = 0.007). Conclusions: There was more severe subclinical LV dysfunction in T2DM patients complicated with DPN than those without DPN, suggesting further prospective study with more active intervention in this cohort of patients. [ABSTRACT FROM AUTHOR]

Since the COVID-19 outbreak, raccoon dogs have been suggested as a potential intermediary in transmitting SARS-CoV-2 to humans. To understand their role in the COVID-19 pandemic and the species barrier for SARS-CoV-2 transmission to humans, we analyzed how their ACE2 protein interacts with SARS-CoV-2 spike protein. Biochemical data showed that raccoon dog ACE2 is an effective receptor for SARS-CoV-2 spike protein, though not as effective as human ACE2. Structural comparisons highlighted differences in the virus-binding residues of raccoon dog ACE2 compared to human ACE2 (L24Q, Y34H, E38D, T82M, R353K), explaining their varied effectiveness as receptors for SARS-CoV-2. These variations contribute to the species barrier that exists between raccoon dogs and humans regarding SARS-CoV-2 transmission. Identifying these barriers can help assess the susceptibility of other mammals to SARS-CoV-2. Our research underscores the potential of raccoon dogs as SARS-CoV-2 carriers and identifies molecular barriers that affect the virus's ability to jump between species. Author summary: Raccoon dogs are thought to have been a crucial link in the chain that led to the spread of the COVID-19 virus to humans. The key to a coronavirus moving from one species to another is its spike protein's ability to bind to receptors on the cells of the new host. In our research, we investigated the interaction between the spike protein of the COVID-19 virus and the ACE2 receptor in raccoon dogs, using both structural and biochemical techniques. We found that the ACE2 receptor in raccoon dogs does indeed work as an effective receptor for the virus, but there are critical differences when compared to the human ACE2 receptor, which may act as barriers to the virus making the jump between raccoon dogs and humans. To our knowledge, this study is the first in-depth examination of these cross-species transmission barriers for the COVID-19 virus, shedding light on how other mammals might be impacted by the virus. Our findings indicate that raccoon dogs could potentially carry and pass the COVID-19 virus on to humans, providing foundational knowledge for how the virus can navigate between different species. [ABSTRACT FROM AUTHOR]

Grain crushing underpins key mechanical behaviours of granular materials. A variety of factors, including grading, particle shapes and loading conditions, have been recognised to affect the crushability of grains and the overall behaviour of a granular material. Among them, the role of intermediate principal stress in a general stress condition on the shear behaviour of crushable granular sand remains less understood, owing to the scarcity of experimental data and analytical tools available. In this paper, a multi-scale computational approach is employed to investigate the shear behaviour of crushable granular sand under general stress conditions with varying intermediate principal stresses and confining pressures. The computational approach features multi-scale coupling between non-smooth contact dynamics and peridynamics, and offers a rigorous way to consider the intertwined evolution of particle size and shape during the process of grain crushing. The numerical study helps to quantify comprehensively and analyse the grain crushing-induced changes of macro- and micro-scale material behaviours including strength, deformability, particle size and shape evolution, particle-scale forces and contact conditions, and the development of anisotropy. The competition between a void-filling mechanism due to grain size change and enhanced friction and interlocking due to grain shape change in dictating the deformation of crushable sand is further discussed. The findings offer insights into the complex behaviours of crushable granular materials under general stress conditions and facilitate future development of physics-based constitutive theories on crushable sand. [ABSTRACT FROM AUTHOR]

To assure operational safety in the airport apron area and track the process of ground service, it is necessary to analyze key targets and their activities in the airport apron surveillance videos. This research shows an activity identification algorithm for ground service objects in an airport apron area and proposes an improved YOLOv5 algorithm to increase the precision of small object detection by introducing an SPD-Conv (spath-to-depth-Conv) block in YOLOv5's backbone layer. The improved algorithm can efficiently extract the information features of small-sized objects, medium-sized objects, and moving objects in large scenes, and it achieves effective detection of activities of ground service in the apron area. The experimental results show that the detection average precision of all objects is more than 90%, and the whole class mean average precision (mAP) is 98.7%. At the same time, the original model was converted to TensorRT and OpenVINO format models, which increased the inference efficiency of the GPU and CPU by 55.3 and 137.1%, respectively. [ABSTRACT FROM AUTHOR]

The wavelet transform cannot maintain a balance in image edge preservation and detail processing and the multi-scale Retinex algorithm is prone to halo artifacts and serious noise pollution in images. In order to solve the above problems, a mine low illumination image enhancement algorithm is proposed by combining the wavelet transform with the multi-scale Retinex algorithm based on multi-scale guided filtering. Firstly, the algorithm decomposes the low illumination image into wavelets to obtain the high-frequency and low-frequency components. Secondly, the wavelet denoising is applied to the high-frequency components of the image using a three-stage threshold function, and nonlinear global luminance correction is applied to the low-frequency components of the image to enhance the image luminance. Moreover, the multi-scale guided filter function is used to estimate the illumination components instead of the Gaussian filter function of the traditional multi-scale Retinex algorithm, and then the reflection components are obtained. The principal component analysis method is used to fuse the reflection component and the non-linear global luminance correction image so as to improve image edge detail preservation effect effectively. Finally, the wavelet reconstruction is performed on the high-frequency components and low-frequency components of the image, and the wavelet reconstructed image is nonlinearly transformed to solve the image graying problem. The experimental results show that the algorithm has strong noise suppression capability, can improve the image luminance and contrast effectively, make the image edge preservation performance and detail information richness effectively balanced, and avoid the image halo artifacts and color distortion.

In this work, the binding mechanism of myofibrillar protein (MP) with malondialdehyde and 4-hydroxy-2-nonenal under low temperature vacuum heating was investigated via multispectroscopic and molecular docking. The results showed that binding interaction and increasing temperature caused significant changes in the conformations as well as a decrease in the value of protein intrinsic fluorescence, surface hydrophobicity, and fluorescence excitation-emission matrix spectra. Furthermore, the decrease in α-helix and β-turn, increase in β-sheet and a random coil of MP, imply the MP molecules to be more unfolded. Isothermal titration calorimetry and molecular docking results showed that main driving force for binding with MP was hydrogen bond, and the binding ability of malondialdehyde was superior to that of 4-hydroxy-2-nonenal. Moreover, increasing the heating temperature was beneficial to the binding reaction and intensified the conformational transition of MP. These results will provide a reference for further studies on the lipid and protein interaction of sturgeon.