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1.
Int J Biol Macromol ; 274(Pt 1): 133290, 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38908631

RESUMEN

MccY is a novel, structurally stable microcin with antibacterial activity against Enterobacteriaceae. However, the bioavailability of orally administrated MccY is unknown. This study evaluated the effects of MccY as a antimicrobial on pre-digestion in vitro and its intake, digestion and gut metabolism in vivo. The result of pre-digestion results that MccY maintained its biological activity and was resistant to decomposition. The study established a safe threshold of 4.46-9.92 mg/kg for the MccY dosage-body weight relationship in BALB/c mice. Mice fed with MccY demonstrated improved body weight and intestinal barrier function, accompanied with increased IgM immunogenicity and decreased levels of TNF-α, IL-6, and IL-10 in the intestine. MccY significantly facilitates the growth and activity of probiotics including Lactobacillus, Prevotella, and Bacteroides, and leading to the production of SCFAs and MCFAs during bacterial interactions. Furthermore, MccY effectively protects against the inflammatory response caused by Salmonella Typhimurium infection and effectively clears the Salmonella bacteria from the gut. In conclusion, MccY is seen as a promising new therapeutic target drug for enhancing the intestinal microbe-barrier axis and preventing enteritis.

2.
Inorg Chem ; 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38937959

RESUMEN

Type I photosensitizers offer an advantage in photodynamic therapy (PDT) due to their diminished reliance on oxygen levels, thus circumventing the challenge of hypoxia commonly encountered in PDT. In this study, we present the synthesis and comprehensive characterization of a novel type I photosensitizer derived from a cyclometalated Ir(III)-rhodamine complex. Remarkably, the complex exhibits a shift in absorption and fluorescence, transitioning from "off" to "on" states in aprotic and protic solvents, respectively, contrary to initial expectations. Upon exposure to light, the complex demonstrates the effective generation of O2- and ·OH radicals via the type I mechanism. Additionally, it exhibits notable photodynamic antibacterial activity against both Gram-positive and Gram-negative bacteria, demonstrated through in vitro and in vivo experiments. This research offers valuable insights for the development of novel type I photosensitizers.

3.
Entropy (Basel) ; 26(6)2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38920476

RESUMEN

Block compressed sensing (BCS) is a promising method for resource-constrained image/video coding applications. However, the quantization of BCS measurements has posed a challenge, leading to significant quantization errors and encoding redundancy. In this paper, we propose a quantization method for BCS measurements using convolutional neural networks (CNN). The quantization process maps measurements to quantized data that follow a uniform distribution based on the measurements' distribution, which aims to maximize the amount of information carried by the quantized data. The dequantization process restores the quantized data to data that conform to the measurements' distribution. The restored data are then modified by the correlation information of the measurements drawn from the quantized data, with the goal of minimizing the quantization errors. The proposed method uses CNNs to construct quantization and dequantization processes, and the networks are trained jointly. The distribution parameters of each block are used as side information, which is quantized with 1 bit by the same method. Extensive experiments on four public datasets showed that, compared with uniform quantization and entropy coding, the proposed method can improve the PSNR by an average of 0.48 dB without using entropy coding when the compression bit rate is 0.1 bpp.

4.
Vet Res ; 55(1): 66, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38778424

RESUMEN

The lasso peptide microcin Y (MccY) effectively inhibits various serotypes of Salmonella in vitro, but the antibacterial effect against S. Pullorum in poultry is still unclear. This study was the first to evaluate the safety and anti-S. Pullorum infection of MccY in specific pathogen-free (SPF) chicks. The safety test showed that the body weight, IgA and IgM levels of serum, and cecal microbiota structure of 3 groups of chicks orally administrated with different doses of MccY (5 mg/kg, 10 mg/kg, 20 mg/kg) for 14 days were not significantly different from those of the control group. Then, the chicks were randomized into 3 groups for the experiment of anti-S. Pullorum infection: (I) negative control group (NC), (II) S. Pullorum-challenged group (SP, 5 × 108 CFU/bird), (III) MccY-treated group (MccY, 20 mg/kg). The results indicated that compared to the SP group, treatment of MccY increased body weight and average daily gain (P < 0.05), reduced S. Pullorum burden in feces, liver, and cecum (P < 0.05), enhanced the thymus, and decreased the spleen and liver index (P < 0.05). Additionally, MccY increased the jejunal villus height, lowered the jejunal and ileal crypt depth (P < 0.05), and upregulated the expression of IL-4, IL-10, ZO-1 in the jejunum and ileum, as well as CLDN-1 in the jejunum (P < 0.05) compared to the SP group. Furthermore, MccY increased probiotic flora (Barnesiella, etc.), while decreasing (P < 0.05) the relative abundance of pathogenic flora (Escherichia and Salmonella, etc.) compared to the SP group.


Asunto(s)
Bacteriocinas , Pollos , Microbioma Gastrointestinal , Enfermedades de las Aves de Corral , Salmonelosis Animal , Animales , Microbioma Gastrointestinal/efectos de los fármacos , Enfermedades de las Aves de Corral/microbiología , Salmonelosis Animal/microbiología , Bacteriocinas/administración & dosificación , Bacteriocinas/farmacología , Administración Oral , Salmonella/efectos de los fármacos , Salmonella/fisiología , Organismos Libres de Patógenos Específicos , Alimentación Animal/análisis , Antibacterianos/farmacología , Antibacterianos/administración & dosificación , Distribución Aleatoria , Funcion de la Barrera Intestinal
5.
Math Biosci Eng ; 21(2): 2991-3015, 2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38454716

RESUMEN

Lung adenocarcinoma, a chronic non-small cell lung cancer, needs to be detected early. Tumor gene expression data analysis is effective for early detection, yet its challenges lie in a small sample size, high dimensionality, and multi-noise characteristics. In this study, we propose a lung adenocarcinoma convolutional neural network (LATCNN), a deep learning model tailored for accurate lung adenocarcinoma prediction and identification of key genes. During the feature selection stage, we introduce a hybrid algorithm. Initially, the fast correlation-based filter (FCBF) algorithm swiftly filters out irrelevant features, followed by applying the k-means-synthetic minority over-sampling technique (k-means-SMOTE) method to address category imbalance. Subsequently, we enhance the particle swarm optimization (PSO) algorithm by incorporating fast-decay dynamic inertia weights and utilizing the classification and regression tree (CART) as the fitness function for the second stage of feature selection, aiming to further eliminate redundant features. In the classifier construction stage, we present an attention convolutional neural network (atCNN) that incorporates an attention mechanism. This improved model conducts feature selection post lung adenocarcinoma gene expression data analysis for classification and prediction. The results show that LATCNN effectively reduces the feature dimensions and accurately identifies 12 key genes with accuracy, recall, F1 score, and MCC of 99.70%, 99.33%, 99.98%, and 98.67%, respectively. These performance metrics surpass those of other comparative models, highlighting the significance of this research for advancing lung adenocarcinoma treatment.


Asunto(s)
Adenocarcinoma del Pulmón , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/genética , Redes Neurales de la Computación , Adenocarcinoma del Pulmón/genética , Algoritmos
6.
Heliyon ; 10(3): e24899, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38317901

RESUMEN

Background: Emerging evidence has demonstrated the impact of psychological stress on intestinal microbiota, however, the precise mechanisms are not fully understood. Enteric glia, a unique type of peripheral glia found within the enteric nervous system (ENS), play an active role in enteric neural circuits and have profound effects on gut functions. In the present study, we tested the hypothesis that enteric glia are involved in the alterations in the intestinal microflora and barrier induced by chronic water-avoidance stress (WAS) in the gut. Methods and results: Western blotting and immunohistochemical (IHC) staining were used to examine the expression of glial fibrillary acidic protein (GFAP), nitric oxide synthetase (NOS) and choline acety1transferase (ChAT) in colon tissues. 16S rDNA sequencing was performed to analyse the composition of the intestinal microbiota in rats. Changes in the tight junction proteins Occludin, Claudin1 and proliferating cell nuclear antigen (PCNA) in the colon tissues were detected after WAS. The abundance of Firmicutes, Proteobacteria, Lactobacillus and Lachnospiraceae_NK4A136 decreased significantly, whereas the abundance of Actinobacteria, Ruminococcaceae_UCG-005 and Christensenellaceae-R-7 increased significantly in stressed rats. Meanwhile, the expression of Occludin, Claudin1 and PCNA significantly decreased after WAS. Treatment with L-A-aminohexanedioic acid (L-AA), a gliotoxin that blunts astrocytic function, obviously decreased the abundance of Actinobacteria, Ruminococcaceae_UCG-005 and Christensenel-laceae_R-7 in stressed rats and significantly increased the abundance of Proteobacteria, Lactobacillus and Lachnospiraceae_NK4A136. In addition, the protein expression of colon Occludin, Claudin1, and PCNA increased after intraperitoneal injection of L-AA. Furthermore, the expression level of NOS in colon tissues was significantly decreased, whereas that of ChAT was significantly increased following L-AA treatment. Conclusions: Our results showed that enteric glial cells may contribute to WAS-induced changes in the intestinal microbiota and barrier function by modulating the activity of NOS and cholinergic neurones in the ENS.

7.
Polymers (Basel) ; 16(4)2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38399905

RESUMEN

Solid hygroscopic materials are extensively utilized in diverse fields, including adsorption heat transfer, adsorption heat storage, atmospheric water harvesting (AWH), and air conditioning dehumidification. The efficacy and energy efficiency of these materials in practical applications are significantly influenced by their adsorption and desorption properties. Yet, the introduction of inorganic salts to boost adsorption performance can result in issues like salt leakage. In this research, we prepared a polyacrylamide hydrogel through free radical polymerization, and its water-absorbing capabilities were improved by incorporating the hygroscopic salt lithium chloride. We compared it to a salt-based porous adsorbent, AlFum-LiCl, which also exhibited strong water adsorption properties and the potential for large-scale production. While AlFum-LiCl suffered from limited pores and salt leakage during high water uptake, the optimized PAM-LiCl displayed superior water sorption capabilities, showing no salt leakage even at water uptake of up to 3.5 g/g. At 25 °C, PAM-LiCl achieved equilibrium water uptake of 1.26 g/g at 30% RH and 3.15 g/g at 75% RH. In this context, utilizing 20 g of PAM-LiCl for the AWH experiment yielded daily water outputs of 8.34 L/kg at 30% RH and 16.86 L/kg at 75% RH. The salt-optimized PAM-LiCl hydrogel offers the benefit of application in higher relative humidity environments without the risk of deliquescence, underscoring its promise for atmospheric water harvesting.

8.
IEEE Trans Biomed Eng ; 71(6): 1732-1744, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38170654

RESUMEN

OBJECTIVE: To develop a novel multi-TE MR spectroscopic imaging (MRSI) approach to enable label-free, simultaneous, high-resolution mapping of several molecules and their biophysical parameters in the brain. METHODS: The proposed method uniquely integrated an augmented molecular-component-specific subspace model for multi-TE 1H-MRSI signals, an estimation-theoretic experiment optimization (nonuniform TE selection) for molecule separation and parameter estimation, a physics-driven subspace learning strategy for spatiospectral reconstruction and molecular quantification, and a new accelerated multi-TE MRSI acquisition for generating high-resolution data in clinically relevant times. Numerical studies, phantom and in vivo experiments were conducted to validate the optimized experiment design and demonstrate the imaging capability offered by the proposed method. RESULTS: The proposed TE optimization improved estimation of metabolites, neurotransmitters and their T2's over conventional TE choices, e.g., reducing variances of neurotransmitter concentration by  âˆ¼  40% and metabolite T2 by  âˆ¼  60%. Simultaneous metabolite and neurotransmitter mapping of the brain can be achieved at a nominal resolution of 3.4 × 3.4 × 6.4 mm 3. High-resolution, 3D metabolite T2 mapping was made possible for the first time. The translational potential of the proposed method was demonstrated by mapping biochemical abnormality in a post-traumatic epilepsy (PTE) patient. CONCLUSION: The feasibility for high-resolution mapping of metabolites/neurotransmitters and metabolite T2's within clinically relevant time was demonstrated. We expect our method to offer richer information for revealing and understanding metabolic alterations in neurological diseases. SIGNIFICANCE: A novel multi-TE MRSI approach was presented that enhanced the technological capability of multi-parametric molecular imaging of the brain. The proposed method presents new technology development and application opportunities for providing richer molecular level information to uncover and comprehend metabolic changes relevant in various neurological applications.


Asunto(s)
Encéfalo , Imagen Molecular , Fantasmas de Imagen , Encéfalo/diagnóstico por imagen , Encéfalo/metabolismo , Humanos , Imagen Molecular/métodos , Algoritmos , Procesamiento de Imagen Asistido por Computador/métodos , Imagen por Resonancia Magnética/métodos , Procesamiento de Señales Asistido por Computador , Espectroscopía de Resonancia Magnética/métodos
9.
Artículo en Inglés | MEDLINE | ID: mdl-38290466

RESUMEN

Objective: The present study was performed to evaluate the effect of ultrasound-guided erector spinae plane block (ESPB) on pain after laparoscopic transabdominal preperitoneal (TAPP) repair. Therefore, improved postoperative pain management is crucial for enhancing the overall patient experience and recovery. Methods: This prospective, double-blind, randomized controlled trial enrolled 40 male patients with a unilateral inguinal hernia at Xi'an Aerospace General Hospital from November 1, 2020, to February 1, 2021. Participants were assigned through a random number table at a 1:1 ratio to receive either ESPB with 20 ml 0.5% ropivacaine in the experimental group (Group E) or ESPB with 20 ml normal saline in the control group (Group C), with 20 cases in each group. The primary outcome was assessed using visual analogue scale (VAS) scores for exercise pain at 2h, 6h, 12h, 18h, and 24h postoperatively. Secondary outcomes included time lapses before patient-controlled intravenous analgesia (PCIA) use, intraoperative remifentanil usage, additional sufentanil, postoperative nalbuphine consumption, analgesic remedies at 24h postoperatively, and incidence of postoperative adverse events. Results: Group E provided more pain mitigation for patients than Group C, as evidenced by the significantly lower VAS scores during exercise pain at 2h (Group C: 1.95±1.19; Group E:4.00±1.38), 6h (Group C: 2.00±1.12; Group E:3.90±1.37), and 12h (Group C: 2.05±1.05; Group E:3.55±1.36) postoperatively (P < .05), and the pain mitigation for Group C was significant only at 18h and 24h postoperatively compared to at 2h postoperatively (P < .05). Group E resulted in significantly reduced intraoperative use of remifentanil and, additional sufentanil and postoperative nalbuphine consumption versus Group C (P < .05). Group E exhibited a better pain tolerance than Group C, as demonstrated by the longer time lapse before the use of PCIA (RR value=5.709, t=8.446, P < .05). Group C required more analgesic remedies within 24 h after surgery than Group E (P < .05). Group E did not increase the risk of postoperative adverse events, given the absence of statistical significance in the intergroup comparison (P > .05). Conclusion: Ultrasound-guided ESPB demonstrates notable benefits by decreasing intraoperative and postoperative anesthetic drug requirements, enhancing pain management, and elevating postoperative comfort and quality of life for patients. While acknowledging the study's limitations, it is crucial to highlight the potential clinical implications of these findings. The incorporation of ESPB with ropivacaine into postoperative pain management protocols could represent a significant advancement in clinical practice. The observed improvements in pain management and reduced reliance on anesthetic drugs may lead to more tailored and efficient postoperative care, potentially enhancing patient recovery experiences. Further research and practical implementation studies are warranted to fully elucidate the specific impact and optimal integration of ESPB with ropivacaine within broader clinical settings.

10.
Environ Sci Pollut Res Int ; 31(6): 9582-9595, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38194173

RESUMEN

Previous researches seldom studied the selection of buffer distance between geological hazards (positive samples) and non-geological hazards (negative samples), and its reasonable selection plays a very important role in improving the accuracy of susceptibility zoning, protecting the environment and reducing the cost of hazard management. Based on GIS technology and random forest (RF) and frequency-ratio random forest (FR-RF) models, this study innovatively explored the influence of randomly selected non-geological hazard samples outside different buffer distances on the susceptibility evaluation results, with buffer distances of 100 m, 500 m, 1000 m and 2000 m in sequence. The results show that through the confusion matrix and ROC curve test, the accuracy of the model increases first and then decreases with the increase of buffer distance. Both RF and FR-RF models have the highest accuracy when the buffer distance is 1000 m, and the accuracy of the RF model is generally higher than that of the FR-RF model under the same buffer distance. Similar attribute values of positive samples and randomly selected negative samples or "extreme" attribute values of negative samples are the main reasons for the differences in evaluation results of different buffer distances. According to the weight analysis of causative factors, the distance from road, the distance from river and the normalized vegetation index (NDVI) are the main factors affecting the occurrence of hazards. The high and very high susceptibility areas in the study area are mainly distributed on both sides of roads and water systems, which are the key areas for hazard prevention and reduction. The HMC of RF-1000m decreased by 3.55% on average compared with other models. The results of this study improve the accuracy of geological hazard susceptibility assessment, maintain the safety of ecological environment, and provide a scientific basis for the selection of buffer distance index in local and surrounding areas in the future.


Asunto(s)
Geología , Ríos
11.
J Phys Chem Lett ; 14(51): 11550-11557, 2023 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-38096129

RESUMEN

Polymer dielectrics with excellent high-temperature capacitive energy storage performance are in urgent demand for modern power electronic devices and high-voltage electrical systems. Nevertheless, the energy storage capability usually degrades dramatically at increased temperatures, owing to the exponentially increased conduction loss. Herein, a trace of commercially available aluminum nitride (AlN) nanoparticles is incorporated into the poly(ether imide) (PEI) matrix to inhibit the conduction loss. The nanostructured AlN component with a large specific surface area can provide abundant sites for the collision of carriers. More importantly, the generated new trap energy levels can immobilize the carriers, accordingly contributing to the reduction in leakage current. From this, the discharged energy density at 150 °C of PEI composites increases by 82.13% from 2.63 J/cm3 for pristine PEI to 4.79 J/cm3 for PEI composites. This work establishes a facile approach to enhancing the high-temperature capacitive performance of polymer dielectrics.

12.
ACS Omega ; 8(50): 47938-47953, 2023 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-38144124

RESUMEN

The Ediacaran Doushantuo phosphate deposit in Kaiyang, Guizhou Province, China, contains thick phosphate ores. Most of the ores are reconstituted phosphorite, and there have been few studies of the primary phosphorites, which has led to controversy regarding the origins and nature of mineralization of these phosphate-rich deposits. We identified high-grade primary phosphorites in the Kaiyang area and undertook a stratigraphic, petrological, sedimentological, geochemical, and isotopic study of these rocks. Moving up-section, the Longshui phosphate ore deposit comprises granular, micritic, stromatolitic, honeycomb, and sandy phosphorites. The first four types of phosphorite contain abundant biological structures, such as spherical, lobe-like, and amorphous forms. These are mainly fossils of benthic multicellular red algae, along with other types of algae. These fossils comprise >70% of the phosphorites, indicating that these are protist phosphorites. The ores are massive, unstratified, and contain numerous layered cavity structures, indicating that the ore bed was originally a reef. The phosphorites have P2O5 contents of 38.6-40.2 wt %, with an average of 38.9 wt %. The Al2O3 + TiO2 values are 0.02-0.44 wt %. The δ18O values of the samples vary from 13.76 to 16.57‰, with an average of 14.60‰, and δ13C values range from -15.789 to -8.697‰, with an average of -13.133‰. The samples exhibit rare-earth element patterns that are enriched with middle rare-earth elements and have strongly negative Ce anomalies. The geochemical features show that the reef was deposited in clear and oxidized waters. The discovery of this high-grade protist phosphorite shows that the involvement of algae was key to the formation of the Kaiyang phosphate-rich deposit.

13.
Adv Mater ; : e2309640, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-38100119

RESUMEN

Superior high-temperature capacitive performance of polymer dielectrics is critical for the modern film capacitor demanded in the harsh-environment electronic and electrical systems. Unfortunately, the capacitive performance degrades rapidly at elevated temperatures owing to the exponential growth of conduction loss. The conduction loss is mainly composed of electrode and bulk-limited conduction. Herein, the contribution of surface and bulk factors is unified to conduction loss, and the loss is thoroughly suppressed. The experimental results demonstrate that the polar oxygen-containing groups on the surface of polymer dielectrics can act as the charge trap sites to immobilize the injected charges from electrode, which can in turn establish a built-in field to weaken the external electric field and augment the injection barrier height. Wide bandgap aluminum oxide (Al2 O3 ) nanoparticle fillers can serve as deep traps to constrain the transport of injected or thermally activated charges in the bulk phase. From this, at 200 °C, the discharged energy density with a discharge-charge efficiency of 90% increases by 1058.06% from 0.31 J cm-3 for pristine polyetherimide to 3.59 J cm-3 for irradiated composite film. The principle of simultaneously inhibiting the electrode and bulk-limited conduction losses could be easily extended to other polymer dielectrics for high-temperature capacitive performance.

14.
Environ Sci Pollut Res Int ; 30(58): 122245-122261, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37968480

RESUMEN

The rational selection of the proportion between geological disasters (positive samples) and non-geological disasters (negative samples) holds significant importance in enhancing the precision of geological disaster susceptibility assessment and maintaining the sustainable development of the ecological environment. This paper, using Liulin County as an example, employs correlation analysis to select appropriate evaluation factors. A Random Forest (RF) model, based on GIS technology, is used for susceptibility mapping. Sample ratios of 1:1, 1:1.5, 1:3, 1:5, and 1:10 are applied. The results indicate that, through a confusion matrix test, the model's predictive performance reaches a "tipping point" at a sample ratio of 1:5. The receiver operating characteristic (ROC) curve test shows that the 1:5 model performs best. Combining the proportion of susceptibility zones and disaster points, 1:5 is identified as the most suitable ratio for assessing geological disaster susceptibility in the study area. High and very high susceptibility zones are primarily concentrated in the central and northern regions alongside roads and rivers, making these areas key focuses for disaster prevention and reduction in Liulin County. The accuracy of the model's predictions increases with a greater number of samples, but it does not continue to rise indefinitely; accuracy declines after a critical threshold is crossed. These research findings complement prior studies, promote advances in geological disaster prevention technology, and maintain geological environmental stability, all of which are crucial for the local economy's stability and sustainable development.


Asunto(s)
Desastres , Bosques Aleatorios , Geología , Desarrollo Sostenible , Ríos
15.
Microbiol Spectr ; 11(6): e0178423, 2023 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-37819128

RESUMEN

IMPORTANCE: Diseases caused by Enterobacteriaceae multidrug-resistant strains have become increasingly difficult to manage. It is necessary to verify the new antibacterial drug MccY effect on non-typhoid Salmonella infection in mice since it is regarded as a promising microcin. The results demonstrated that MccY has a potential therapeutic application value in the protection against Salmonella-induced intestinal damage and alleviating related intestinal dysbiosis and metabolic disorders. MccY could be a promising candidate as an antimicrobial or anti-inflammatory agent for treating infectious diseases.


Asunto(s)
Microbioma Gastrointestinal , Ratones , Animales , Funcion de la Barrera Intestinal , Inflamación/tratamiento farmacológico , Salmonella , Péptidos , Disbiosis/microbiología
16.
Materials (Basel) ; 16(19)2023 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-37834697

RESUMEN

We have particularly investigated the correlation law of the effect of different carbon black fillings on the hyper-elastic mechanical behavior of natural rubber by conducting uniaxial tensile tests over a wide range of deformations with different volume fractions of carbon black fillings (0%, 4.7%, 8.9%, 12.8%, 16.4%, 19.7%, 22.7% and 25.2%). The results show that the stress-strain curve for carbon black filled rubber increases with the amount of filling, meaning that the rubber gradually becomes "harder". We explore the correlation between the carbon black filling volume and the parameters of the Yeoh constitutive model by examining the Yeoh constitutive model to characterize the hyper-elastic mechanical behavior of rubber with different carbon black fillings. A quantitative relationship between the material parameters and the carbon black filling volume in the Yeoh constitutive model is presented. A method for calculating the material parameters of the Yeoh constitutive model is developed, and it predicts the correlation between the hyper-elastic properties of rubber and the volume fraction of the carbon black filling.

17.
Heliyon ; 9(8): e19252, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37664716

RESUMEN

Accurate engine gas path component fault diagnosis methods are key to ensuring the reliability and safety of engine operations. At present, the effectiveness of the data-driven gas path component fault diagnosis methods has been widely verified in engineering applications. The deep stack neural network (DSN), as a common deep learning neural network, has been gaining more attention in gas path fault diagnosis studies. However, various gas path component faults with strong coupling effects could occur simultaneously, resulting the DSN method less effective for engine gas path fault diagnosis. In order to improve the prediction performance of the DSN handling multiple gas path component fault diagnosis, a sparse regularization and representation method was proposed. The sparse regularization term is used to expand the traditional deep stacking neural network in the sparse representation, and the predicted output tag is close to the target output tag through this term. The diagnosis performance of six different neural network methods were compared by various engine gas path component fault diagnosis types. The results show that the proposed sparse regularization method significantly improves the prediction performance of the DSN, with an accuracy rate 99.9% under various gas path component fault conditions, which is higher than other methods. The proposed engine gas path component fault diagnosis method can handle multiple coupling gas path faults, and help engine operators to develop maintenance plans for the purpose of engine health management.

18.
Polymers (Basel) ; 15(18)2023 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-37765532

RESUMEN

The water sorption and desorption properties of solid adsorbent materials are crucial in rotary dehumidification systems. Metal organic frameworks (MOFs) and hydrogels are mostly at the laboratory stage due to factors like the synthesis process and yield. In this study, we utilized an eco-friendly and large-scale synthesis method to prepare polyacrylamide (PAM) hydrogels (yielding approximately 500 mL from a single polymerization). Subsequently, PAM was then coated onto glass fiber paper (GFP), which serves as a commonly employed substrate in desiccant wheels. By incorporating the hygroscopic salt LiCl and optimizing the content of each component, the water sorption performance of the composite was notably improved. The water sorption and desorption performances, as well as cycling stability, were evaluated and compared with composites containing aluminum fumarate, LiCl, and GFP (AlFum-LiCl&GFP). The results revealed that PAM-LiCl&GFP outperformed AlFum-LiCl&GFP in terms of sorption capacity throughout various relative humidity (RH) levels. It achieved a water uptake of 1.06 g·g-1 at 25 °C and 30% RH, corresponding to a water sorption rate coefficient K of 15.32 × 10-4 s-1. Furthermore, the lower desorption temperature (60 °C) resulting in a desorption ratio of 82.6%, along with the excellent cycling stability and effective performance as a desiccant wheel module, provide evidence for the potential application of PAM-LiCl&GFP in desiccant wheels.

19.
Plants (Basel) ; 12(14)2023 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-37514247

RESUMEN

The PLATZ (plant AT protein and zinc-binding protein) transcription factor family is involved in the regulation of plant growth and development and plant stress response. In this study, 24 SlPLATZs were identified from the cultivated tomato genome and classified into four groups based on the similarity of conserved patterns among members of the same subfamily. Fragment duplication was an important way to expand the SlPLATZ gene family in tomatoes, and the sequential order of tomato PLATZ genes in the evolution of monocotyledonous and dicotyledonous plants and the roles they played were hypothesized. Expression profiles based on quantitative real-time reverse transcription PCR showed that SlPLATZ was involved in the growth of different tissues in tomatoes. SlPLATZ21 acts mainly in the leaves. SlPLATZ9, SlPLATZ21, and SlPLATZ23 were primarily involved in the red ripening, expanding, and mature green periods of fruit, respectively. In addition, SlPLATZ1 was found to play an important role in salt stress. This study will lay the foundation for the analysis of the biological functions of SlPLATZ genes and will also provide a theoretical basis for the selection and breeding of new tomato varieties and germplasm innovation.

20.
BMC Anesthesiol ; 23(1): 233, 2023 07 11.
Artículo en Inglés | MEDLINE | ID: mdl-37434138

RESUMEN

BACKGROUND: This investigation aimed to evaluate the impact of continuous pericapsular nerve group (PENG) block and continuous fascia iliac compartment block (FICB) on postoperative pain following total hip arthroplasty (THA). METHODS: This prospective, randomized, and controlled trial recruited a cohort of fifty-seven patients with unilateral femoral neck fractures from Xi'an Aerospace General Hospital in northwest China between July 2020 and November 2021. These patients were randomly assigned to two groups: the continuous PENG block group (PENG group, n = 29) and the continuous FICB group (FICB group, n = 28). Under ultrasound guidance, PENG block and FICB procedures were performed prior to spinal anesthesia, utilizing 20 ml of 0.25% ropivacaine for PENG block and 30 ml of 0.25% ropivacaine for FICB. Subsequently, a catheter was inserted. All study participants received a standardized postoperative multimodal analgesic regimen, including intravenous administration of 30 mg Ketorolac tromethamine every eight hours and patient-controlled neural analgesia (PCNA) after surgery. Numerical rating scale (NRS) scores at rest and during exercise were recorded at various time points: prior to block (T0), 30 min post-blockade (T1), and 6 h (T2), 12 h (T3), 24 h (T4), and 48 h (T5) postoperatively. Additional data collected encompassed postoperative quadriceps muscle strength, the time of initial ambulation after surgery, the number of effective PCNA activations, rescue analgesia requirements, and occurrences of adverse events (such as nausea and vomiting, hematoma, infection, catheter detachment, or displacement) within 48 h following surgery. RESULTS: In the PENG group, the resting NRS pain scores exhibited lower values at T1, T4, and T5 than those at T0. Furthermore, exercise NRS pain scores at T1-T5 were lower in the PENG group than in the FICB group. Similarly, during the same postoperative period, the PENG group demonstrated enhanced quadriceps strength on the affected side compared to the FICB group. Additionally, the PENG group displayed earlier postoperative ambulation and reduced occurrences of effective PCNA activations and rescue analgesia requirements compared to the FICB group. CONCLUSION: Continuous PENG block exhibited superior analgesic efficacy after THA compared to continuous FICB, promoting recovery of quadriceps strength on the affected side and facilitating early postoperative ambulation. TRIAL REGISTRATION: This clinical trial was registered in the China Clinical Trials Center ( http://www.chictr.org.cn ) on 20/07/2020, with the registration number ChiCTR2000034821.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Músculo Cuádriceps , Humanos , Manejo del Dolor , Artroplastia de Reemplazo de Cadera/efectos adversos , Nervio Femoral , Antígeno Nuclear de Célula en Proliferación , Estudios Prospectivos , Ropivacaína , Fascia , Analgesia Controlada por el Paciente , Dolor
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