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1.
Sci Rep ; 14(1): 9324, 2024 04 23.
Artículo en Inglés | MEDLINE | ID: mdl-38654056

RESUMEN

This study constructs a composite indicator system covering the core dimensions of medical equipment input and output. Based on this system, an innovative cone-constrained data envelopment analysis (DEA) model is designed. The model integrates the advantages of the analytic hierarchy process (AHP) with an improved criterion importance through intercriteria correlation (CRITIC) method to determine subjective and objective weights and employs game theory to obtain the final combined weights, which are further incorporated as constraints to form the cone-constrained DEA model. Finally, a bidirectional long short-term memory (Bi-LSTM) model with an attention mechanism is introduced for integration, aiming to provide a novel and practical model for evaluating the effectiveness of medical equipment. The proposed model has essential reference value for optimizing medical equipment management decision-making and investment strategies.


Asunto(s)
Equipos y Suministros , Humanos , Modelos Teóricos , Teoría del Juego , Algoritmos
2.
Sci Total Environ ; 919: 170824, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38340861

RESUMEN

Growing concerns have raised about the microplastic eco-coronas in the ultraviolet (UV) disinfection wastewater, which accelerated the pollution of antibiotic resistance genes (ARGs) in the aquatic environment. As the hotspot of gene exchange, microplastics (MPs), especially for the UV-aged MPs, could alter the spread of ARGs in the eco-coronas and affect the resistance of the environment through adsorbing antibiotic resistant plasmids (ARPs). However, the relationship between the MP adsorption for ARPs and ARG spreading characteristics in MP eco-corona remain unclear. Herein, this study explored the distribution of ARGs in the MP eco-corona through in situ investigations of the discharged wastewater, and the adsorption behaviors of MPs for ARPs by in vitro adsorption experiments and in silico calculations. Results showed that the adsorption capacity of MPs for ARPs was enhanced by 42.7-48.0 % and the adsorption behavior changed from monolayer to multilayer adsorption after UV-aging. It was related to the increased surface roughness and oxygen-containing functional groups of MPs under UV treatment. Moreover, the abundance of ARGs in MP eco-corona of UV-treated wastewater was 1.33-1.55 folds higher than that without UV treatment, promoting the proliferation of drug resistance. DFT and DLVO theoretical calculations indicated that the MP-ARP interactions were dominated by electrostatic physical adsorption, endowing the aged MPs with low potential oxygen-containing groups to increase the electrostatic interaction with ARPs. Besides, due to the desorption of ARPs on MPs driven by the electrostatic repulsion, the bioavailability of ARGs in the MP eco-coronas was increased with pH and decreased with salinity after the wastewater discharge. Overall, this study advanced the understanding of the adsorption behavior of MPs for ARPs and provided inspirations for the evaluation of the resistance spread in the aquatic environment mediated by MP eco-coronas.


Asunto(s)
Microplásticos , Plásticos , Aguas Residuales , Adsorción , Farmacorresistencia Microbiana/genética , Antibacterianos , Oxígeno , Genes Bacterianos
3.
Materials (Basel) ; 16(8)2023 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-37109840

RESUMEN

The effects of solid solution treatment duration on the corrosion behavior and microstructure behavior of the cast Mg-8.5Li-6.5Zn-1.2Y (wt.%) alloy were investigated. This study revealed that with the treatment time for solid solutions increasing from 2 h to 6 h, the amount of α-Mg phase gradually decreases, and the alloy presents a needle-like shape after solid solution treatment for 6 h. Meanwhile, when the solid solution treatment time increases, the I-phase content drops. Exceptionally, under 4 h of solid solution treatment, the I-phase content has increased, and it is dispersed uniformly over the matrix. What we found in our hydrogen evolution experiments is that the hydrogen evolution rate of the as-cast Mg-8.5Li-6.5Zn-1.2Y alloy following solid solution processing for 4 h is 14.31 mL·cm-2·h-1, which is the highest rate. In the electrochemical measurement, the corrosion current density (icorr) value of as-cast Mg-8.5Li-6.5Zn-1.2Y alloy following solid solution processing for 4 h is 1.98 × 10-5, which is the lowest density. These results indicate that solid solution treatment can significantly improve the corrosion resistance of the Mg-8.5Li-6.5Zn-1.2Y alloy. The I-phase and the α-Mg phase are the primary elements influencing the corrosion resistance of the Mg-8.5Li-6.5Zn-1.2Y alloy. The existence of the I-phase and the border dividing the α-Mg phase and ß-Li phase easily form galvanic corrosion. Although the I-phase and the boundary between the α-Mg phase and ß-Li phase will be corrosion breeding sites, they are more effective in inhibiting corrosion.

4.
Materials (Basel) ; 16(8)2023 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-37110067

RESUMEN

Magnesium-lithium alloys are popular in the lightweight application industry for their very low density. However, as the lithium content increases, the strength of the alloy is sacrificed. Improving the strength of ß-phase Mg-Li alloys is urgently needed. The as-rolled Mg-16Li-4Zn-1Er alloy was multidirectionally rolled at various temperatures in comparison to conventional rolling. The results of the finite element simulations showed that multidirectional rolling, as opposed to conventional rolling, resulted in the alloy effectively absorbing the input stress, leading to reasonable management of stress distribution and metal flow. As a result, the alloy's mechanical qualities were improved. By modifying the dynamic recrystallization and dislocation movement, both high-temperature (200 °C) and low-temperature (-196 °C) rolling greatly increased the strength of the alloy. During the multidirectional rolling process at -196 °C, a large number of nanograins with a diameter of 56 nm were produced and a strength of 331 MPa was obtained.

5.
Front Med (Lausanne) ; 10: 1239795, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38239616

RESUMEN

Introduction: In the rapidly evolving field of digital public health, effective management of medical equipment is critical to maintaining high standards of healthcare service levels and operational efficiency. However, current decisions to replace large medical equipment are often based on subjective judgments rather than objective analyses and lack a standardized approach. This study proposes a multi-criteria decision-making model that aims to simplify and enhance the medical equipment replacement process. Methods: The researchers developed a multi-criteria decision-making model specifically for the replacement of medical equipment. The model establishes a system of indicators for prioritizing and evaluating the replacement of large medical equipment, utilizing game theory to assign appropriate weights, which uniquely combines the weights of the COWA and PCA method. In addition, which uses the GRA method in combination with the TOPSIS method for a more comprehensive decision-making model. Results: The study validates the model by using the MRI equipment of a tertiary hospital as an example. The results of the study show that the model is effective in prioritizing the most optimal updates to the equipment. Significantly, the model shown a higher level of differentiation compared to the GRA and TOPSIS methods alone. Discussion: The present study shows that the multi-criteria decision-making model presented provides a powerful and accurate tool for optimizing decisions related to the replacement of large medical equipment. By solving the key challenges in this area as well as giving a solid basis for decision making, the model makes significant progress toward the field of management of medical equipment.

6.
Int J Mol Sci ; 24(1)2022 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-36613832

RESUMEN

Fresh sweet corn has a series of physiological and biochemical reactions after picking due to the high moisture content, leading to damaged nutritional value. Rapid freezing of sweet corn after harvest can minimize tissue damage and quality deterioration. In this study, freshly harvested sweet corn was frozen by ultrasound-assisted freezing, brine freezing, strong wind freezing, and refrigerator freezing. The effects of different freezing methods on hardness, water loss, color, epidermal structure, soluble solids content, soluble sugars content, peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX) activities of frozen sweet corn during storage were investigated. The results showed that brine freezing and strong wind freezing could effectively reduce the quality loss of sweet corn, keep the color, soluble sugars, and soluble solids content of the sweet corn, delay the decrease in antioxidant enzyme activity, and maintain the quality of sweet corn during long term storage.


Asunto(s)
Antioxidantes , Zea mays , Zea mays/química , Congelación , Peroxidasa , Valor Nutritivo
7.
Plants (Basel) ; 10(8)2021 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-34451660

RESUMEN

Freshly cut vegetables are susceptible to microbial contamination and oxidation during handling and storage. Hence, light-emitting diode technology can effectively inhibit microbial growth and improve antioxidant enzyme activity. In this paper, the freshly cut amaranth was treated with different intensities of blue light-emitting diode (LED460nm) over 12 days. Chlorophyll content, ascorbic acid content, antioxidant capacity, antioxidant enzymes activity, the changes in microbial count, and sensorial evaluation were measured to analyze the effects of LED treatment on the amaranth. Blue LED460nm light irradiation improved the vital signs of the samples and extended the shelf life by 2-3 days. The AsA-GSH cycle was effectively activated with the irradiation of 30 µmol/(m2·s) blue LED460nm light. According to the results, the LED460nm light could retard the growth of colonies and the main spoilage bacteria, Pseudomonas aeruginosa, of freshly cut amaranth.

8.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 46(12): 762-4, 2011 Dec.
Artículo en Chino | MEDLINE | ID: mdl-22333361

RESUMEN

OBJECTIVE: To evaluate the effect of denture base resin surface pretreatment with chemical etchants on microleakage and bond strength between silicone-based resilient liner and denture base resin. The initial bending strength of denture base resin after surface pretreatment was also examined. METHODS: Thirty-six polymethyl methacrylate (PMMA) denture base resin blocks (30 mm × 30 mm × 2 mm) were prepared and divided into three groups: group acetone, group methyl methy acrylate (MMA) and group control. Subsequently, a 2 mm silicone-based resilient liner was applied between every two blocks. After 5000 cycles in the thermal cycler (5 and 55°C), they were immersed in the (131) I solution for 24 hours and γ-ray counts were measured. Another 36 PMMA resin blocks (30 mm × 10 mm × 7.5 mm) were prepared. The blocks were divided into three groups and treated as mentioned above. A 3 mm silicone-based resilient liner was applied between every two blocks. After 5000 thermal cycles, tensile bond strength of the sample was measured in a universal testing machine. Another 18 PMMA resin blocks (65 mm × 10 mm × 3.3 mm) were prepared. They were divided into 3 groups and treated in the same way. After an adhesive was applied, the bending strength was measured with three-piont bending test. RESULTS: Two experimental groups showed lower microleakage (520.0 ± 562.2 and 493.5 ± 447.9) and higher tensile bond strength [(1.5 ± 0.4) and (1.4 ± 0.5) MPa] than the group control [microleakage: (1369.5 ± 590.2); tensile bond strength: (0.9 ± 0.2) MPa, P < 0.05]. There was no statistically significant difference between group acetone and MMA in microleakage and tensile bond strength (P > 0.05). There was no statistically significant difference in bending strength among the three groups (P > 0.05). CONCLUSIONS: Treating the denture base resin surface with acetone and MMA decreased the microleakage, increased the tensile bond strength between the two materials and did not make the initial bending strength of denture base resin decline.


Asunto(s)
Recubrimiento Dental Adhesivo , Bases para Dentadura , Siliconas , Cementos Dentales , Materiales Dentales , Alineadores Dentales , Dimetilpolisiloxanos , Humanos , Ensayo de Materiales , Polimetil Metacrilato , Elastómeros de Silicona , Propiedades de Superficie , Resistencia a la Tracción
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