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Due to the existence of SAR interferogram noise, the quality of the interferogram is seriously affected. Therefore, to suppress the influence of phase noise, many scholars have carried out a lot of research on SAR interferogram noise reduction, but existing studies have difficulty maintaining edge details while also considering effective noise reduction. Therefore, we proposed an improved wavelet denoising algorithm for SAR interferogram using fast nonlocal means filtering. The algorithm was divided into three steps. First, the appropriate wavelet basis was selected and the decomposition level was determined by white noise detection to achieve wavelet decomposition. Then, after non-local processing of wavelet coefficients, the threshold denoising rule was constructed by improving the threshold function to achieve the first denoising. Finally, fast non-local means filtering was used for the second denoising. To verify the effectiveness and superiority of the proposed method, experimental verification of simulated data and real data was conducted. Experimental results show that the proposed method can obtain a more ideal SAR interferogram after noise reduction and has better qualitative and quantitative evaluation than the competitive methods, which indicates that the proposed method can achieve effective denoising for SAR interferograms while preserving the detailed features at smaller window settings. [ABSTRACT FROM AUTHOR]

In order to study the influence of defect geometric parameters (width, thickness) on the electromagnetic characteristics of the space around the defect in the process of eddy current testing of metal spheres, based on the principle of eddy current testing, a metal sphere detection model with different defect parameters was established by COMSOL software for simulation. The distribution of the magnetic field around the defect under different parameters is analyzed with the help of the butterfly diagram composed of the radial magnetic induction intensity and the axial magnetic induction intensity. The results show that: When the width of the corrosion defect is different, the butterfly diagram will change differently. When the width is small, the butterfly diagram basically does not change. When the width reaches a certain value, the butterfly diagram begins to change significantly. The intersection of the graph and the initial butterfly graph is defined as the influence node, and the width of the defect can be quantitatively analyzed according to the sequence of the influence nodes. The influence of the thickness of the corrosion defect on the magnetic field on the surface of the sphere is different under different defect widths. The larger the thickness of the corrosion defect, the greater the influence on the magnetic field near the center of the defect, and the deeper the depression of the butterfly diagram. [ABSTRACT FROM AUTHOR]

Sufficient labeled fault samples are the key to ensuring the performance of deep learning diagnostic models. However, in practical engineering applications, machinery and equipment operate normally most of the time, and it is difficult to collect enough fault data. In contrast, through the kinetics analysis method, simulation data sets of various fault types can be easily obtained. However, there is a difference in distribution between simulation data and real data. The deep learning diagnosis model trained directly with simulation data lacks versatility and cannot be applied to fault diagnosis of real data. To this end, this paper proposes a simulation datadriven deep transfer learning fault diagnosis method, which applies the fault diagnosis knowledge in the simulation data to the real data fault diagnosis task. The effectiveness of the method is verified by experiments on the two-stage planetary gearbox in the Drivetrain Diagnostics Simulator (DDS) test bench. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the effect of dietary supplementation of two omega fatty acids on in vitro rumen fermentation, microbial populations, total gas and methane (CH4) production． Methods: Both linoleic and linolenic acids were supplemented at 0 (control), 1, 3, 5 and 7 % of dry matter (DM) in a ration with a high roughage to concentrate ratio (70: 30). Total gas and CH4 were measured at 3, 6, 9, 12 and 24 h of fermentation while pH, volatile fatty acids (VFA), and ammonia nitrogen (NH3-N) concentrations were measured at 24 h using buffalo rumen fluid in an in vitro batch culture system. Microbial populations were determined using 16S-rDNA gene primers by RT-PCR. Results: The results revealed that linoleic acid at 3, 5 and 7 % decreased the concentration of NH3-N (p < 0.05) but linolenic acid at 5 and 7 % increased NH3-N (p < 0.05). A linear decrease (p <0.001) in acetate and butyrate, coupled with linear increase (p <0.001) in propionate was observed in response to treatment. Furthermore, supplementation of 3, 5 and 7 % of both fatty acids linearly (p < 0.001) decreased total gas and CH4 production when compared to the control. The addition of linoleic acid linearly (p < 0.001) decreased the number of protozoa without affecting methanogens, while linolenic acid linearly and quadratically (p < 0.001) reduced the population of both protozoa and methanogens (p < 0.05). Conclusion: Linolenic acid is more effective at a 3 % level in reducing methane production (up to 63 %) in high roughage diets. [ABSTRACT FROM AUTHOR]

This study was conducted to evaluate potential of Moringa oleifera seed oil (MOSO) to modulate rumen microflora to mitigate methane (CH4) production in different total mixed rations (TMRs). Three TMRs with different roughage (R) to concentrate (C) ratio were used as substrates (R70:C30, R50:C50 and R30:C70) for in vitro fermentation study using batch culture technique. Results revealed that supplementation of MOSO in different rations with variable roughage to concentrates ratio altered (P < 0.05) CH4 production and fermentation parameters. M. oleifera seed oil at 3 and 4% increased (P < 0.01) microbial protein (MCP) and propionate concentration for all rations but decreased acetate concentration in R70:C30 TMR. Two levels of MOSO (3 and 4%) quadratically increased (P = 0.001) MCP and decreased acetate in R30:C70 while all levels increased propionate. For R30:C70 and R50:C50 rations, MOSO linearly and quadratically decreased (P < 0.001) protozoa and methanogen counts; however, protozoa, methanogens and bacteria were significantly increased in R70:C30 ration without any change in fungal counts. Supplementation of higher level of MOSO (4%) in high roughage ration (R70:C30) showed negative effects on diversity (Shannon index) and evenness of bacterial species as compared to control and lower oil level. Moreover, it also decreased Firmicutes to Bacteroidetes ratio in high roughage rations more obviously at lower levels. Moringa oil also stimulated Prevotella in both high and low roughages diets that indicates its potential to mediate rumen acidosis. Conclusively, MOSO enhanced fermentation kinetics and decreased CH4 production through effective modulation of rumen microbiome. [ABSTRACT FROM AUTHOR]

A microaccelerometer based on gallium arsenide (GaAs) resonant-tunneling diodes (RTDs) is demonstrated. The input acceleration signal can be transformed into an output electrical signal using the mesopiezoresistive effects of the RTDs located at the root of the detection beams. Finite element simulations were performed to design, analyze, and optimize the structures of the accelerometer. The accelerometer was fabricated using a combination of GaAs IC surface and bulk micromachining techniques. Vibrating tests and shock tests were conducted to investigate the accelerometer characteristics. The experimental results revealed that the sensitivity of the RTD accelerometer was 7.91 mV/g. The noise resolution was ~1.264 mg/ pHz, and the working frequency was up to 3 kHz. [ABSTRACT FROM AUTHOR]

This article proposes a novel lightweight attention spatiotemporal joint distribution adaptation network fault diagnosis model to address the key challenges of domain transfer and high model complexity in traditional methods. The novelty lies in 1. Using model compression techniques to reduce the complexity of the network model and improve its computational efficiency; 2. Introducing new domain adaptation and adversarial methods to solve the domain transfer problem. The effectiveness of the proposed model is verified through a transfer experiment of planetary gearbox vibration data. The experimental results show that the proposed model reduces the parameters and computational complexity to 18 % and 15 % of the original model, respectively, and has a diagnostic accuracy of over 98 % in cross-condition transfer tasks, and still maintains an accuracy of over 88 % even under high noise levels. This indicates that the proposed model is an efficient and accurate fault diagnosis model. [ABSTRACT FROM AUTHOR]

Objective • To investigate the impact of an Internet + WeChat platform-based “trinity” remote rehabilitation model involving the hospital, community, and family on stroke patient rehabilitation nursing. Methods • 159 patients with stroke who were discharged from Beijing Luhe Hospital of Capital Medical University from January 1, 2018, to December 31, 2019, were selected and divided into a control group (79 cases) and an experimental group (80 cases) by the random drawing method. The control group was given routine nursing, and the experimental group was given remote rehabilitation nursing intervention by using the WeChat network platform based on the control group. Limb function [Fugl-Meyer Assessment Scale (FMA)] and activities of daily living [Modified Barthel Index (MBI)] were evaluated at enrollment and at the end of 3 months, 6 months and 12 months in both groups. The compliance and satisfaction surveys in the two groups were evaluated after 6 months and 12 months of intervention. Results • (1) Before the intervention, there was no statistical significance in FMA score between the two groups (t = 0.798, P > .05). After 3 months, 6 months and 12 months of intervention, the FMA score in the two groups was increased compared with that before intervention (t = 2.463, P < .05), and the FMA scores in the experimental group at the above time points were higher than those in the control group (ts = 7.057, 14.285, Ps < .05). (2) There was no statistical difference in MBI scores between the two groups before intervention (t = 0.798, P > .05). After 3 months, 6 months, and 12 months of intervention, the MBI score in the two groups was increased compared with that before intervention (t = 0.232, P < .05), and MBI scores in the experimental group at the above time points were higher compared to the control group (ts = 4.959, 8.842, 8.131, Ps < .05). (3) The compliance scores in the experimental group were higher than those in the control group after 6 months and 12 months of intervention (ts = 4.959, 8.842, 8.131, Ps < .05). (4) The satisfaction survey scores in the experimental group after 6 months and 12 months of intervention were higher than those in the control group (ts = 2.120 ~ 14.554, Ps < .05). Conclusion • The Hospital-community-family “trinity” stroke rehabilitation model on the WeChat network platform holds significant importance. Enhancing limb function and daily living for stroke patients improves their quality of life and lessens reliance on caregivers. This positively impacts both survivors’ well-being and healthcare resources. Increased patient satisfaction and compliance suggest a potential revolution in post-stroke care, favoring a more patient-centered approach. Overall, this model has transformative potential for stroke treatment, offering holistic and patient-focused strategies. Its success promises better rehabilitation outcomes, patient satisfaction, and cost reduction, while paving the way for innovative research in stroke treatment and rehabilitation. [ABSTRACT FROM AUTHOR]

In this paper, we take a novel two-translation parallel mechanism based on variable length parallelogram structure as the research object, and carry out the research on the dynamic characteristics of the mechanism. Based on the principle of virtual work, the dynamic model of the new two-translation parallel mechanism is established. By numerically solving the dynamic model, the dynamic behavior of the new mechanism with impact characteristics is found, which provides a theoretical basis for optimizing this new mechanism. [ABSTRACT FROM AUTHOR]

Pea (Pisum sativum L.) is an annual cool-season legume crop. Owing to its role in sustainable agriculture as both a rotation and a cash crop, its global market is expanding and increased production is urgently needed. For both technical and regulatory reasons, neither conventional nor transgenic breeding techniques can keep pace with the demand for increased production. In answer to this challenge, CRISPR/Cas9 genome editing technology has been gaining traction in plant biology and crop breeding in recent years. However, there are currently no reports of the successful application of the CRISPR/Cas9 genome editing technology in pea. We developed a transient transformation system of hairy roots, mediated by Agrobacterium rhizogenes strain K599, to validate the efficiency of a CRISPR/Cas9 system. Further optimization resulted in an efficient vector, PsU6.3-tRNA-PsPDS3-en35S-PsCas9. We used this optimized CRISPR/Cas9 system to edit the pea phytoene desaturase (PsPDS) gene, causing albinism, by Agrobacterium-mediated genetic transformation. This is the first report of successful generation of gene-edited pea plants by this route. [ABSTRACT FROM AUTHOR]

Template-based surface nanopatterning techniques are highly efficient methods in realizing different surface nanopatterns, which are the fundamental structures of various nanodevices. We demonstrate a template of pyramidal silicon nanopore array (PSNA) for direct surface nanopatterning. Using the PSNA templates, deposition experiments of platinum (Pt) and gold-palladium (Au-Pd) particles on chromium-coated silicon substrates were performed. Individual Pt nanocubes and nanocube arrays with different shapes and feature sizes as small as 82 nm were obtained. By tuning the gap between the PSNA template and the substrate, Au-Pd microdot arrays with an average diameter of 7.6 μm were also fabricated. As the nanopore size and shape of the PSNA template can be easily controlled, the corresponding size and shape of the transferred surface nanopatterns are tunable. These results indicate the potential of the PSNA templates for large-scale production of nanopatterns with desired Sizes and Shapes. [ABSTRACT FROM AUTHOR]

The article explores how high-loading single Platinum, Pt atom sites [Pt-O(OH)x] catalyze the CO preferential oxidation, PROX reaction with high activity and selectivity at mild conditions. It reports the synthesis of high-loading single Platinum atom catalysts with oxygen-bonded alkaline ions that stabilize the cationic Platinum.

Background: Chimeric antigen receptors (CARs) presented on T cell surfaces enable redirection of T cell specificity, which has enormous promise in antitumor therapy. However, excessive activity and poor control over such engineered T cells cause significant safety challenges, such as cytokine release syndrome and organ toxicities. To enhance the specificity and controllable activity of CAR-T cells, we report a novel switchable dual-receptor CAR-engineered T (sdCAR-T) cell and a new switch molecule of FITC-HM-3 bifunctional molecule (FHBM) in this study. Methods: We designed a fusion molecule comprising FITC and HM-3. HM-3, an antitumor peptide including an Arg-Gly-Asp sequence, can specifically target integrin αvβ3 that is presented on some tumor cells. Moreover, to improve the specificity of CAR-T cells, we also generated the sdCAR-T cell line against cognate tumor cells expressing human mesothelin (MSLN) and integrin αvβ3. Finally, the activity of sdCAR-T cell and FHBM is verified via in vitro and in vivo experiments. Results: In the presence of FHBM, the designed sdCAR-T cells exerted high activity including activation and proliferation and had specific cytotoxicity in a time- and dose-dependent manner in vitro. Furthermore, using a combination of FHBM in nude mice, sdCAR-T cells significantly inhibited the growth of MSLN+ K562 cells and released lower levels of the cytokines (e.g., interleukin-2, interferon γ, interleukin-6, and tumor necrosis factor α) relative to conventional CAR-T cells, obtaining specific, controllable, and enhanced cytotoxicity. Conclusions: Our data indicate that FHBM can accurately control timing and dose of injected CAR-T cells, and sdCAR-T cells exert significant antitumor activity while releasing lower levels of cytokines for the cognate tumor cells expressing both MSLN and integrin αvβ3. Therefore, combination therapies using sdCAR-T cells and the switch molecule FHBM have significant potential to treat malignancies. [ABSTRACT FROM AUTHOR]

Areca catechu L. nut, a well-known toxic traditional herbal medicine, has been widely used to treat various diseases in China and many other Asian countries for centuries. However, to date the in vivo absorption and metabolism of its multiple bioactive or toxic components still remain unclear. In this study, liquid chromatography coupled with tandem mass spectrometry was used to analyze the major components and their metabolites in rat plasma and urine after oral administration of Areca catechu L. nut extract (ACNE). A total of 12 compounds, including 6 alkaloids, 3 tannins and 3 amino acids, were confirmed or tentatively identified from ACNE. In vivo, 40 constituents, including 8 prototypes and 32 metabolites were identified in rat plasma and urine samples. In summary, this study showed an insight into the metabolism of ACNE in vivo, which may provide helpful chemical information for better understanding of the toxicological and pharmacological profiles of ACNE. [ABSTRACT FROM AUTHOR]

A novel type of π-extended 1,10-phenanthroline, specifically with fused thiophene groups at the less exploited 3-, 4-, 7-, and 8-positions of the phenanthroline ring, and its conjugated polymers were designed and synthesized. The current developed route is based on the Bischler-Napieralski cyclization of the (1,2-phenylene)diamide precursor, which offers a facile and versatile strategy for preparing soluble and well-defined 1,10-phenanthroline derivatives and their analogues. High molecular weight poly(phenanthroline-co-fluorene)s with good solubility in common organic solvents or water were prepared by palladium-catalyzed Suzuki-Miyaura-Schlüter polycondensation. The optical responsive properties of these thiophene-fused 1,10-phenanthroline-containing polymers have demonstrated these polymers could be a good candidate for potential applications as luminescent chemosensor materials thanks to the specific repeating unit along the backbone. [ABSTRACT FROM AUTHOR]