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1.
Sci Rep ; 14(1): 9139, 2024 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-38644375

RESUMEN

This paper aims to investigate the dynamic response characteristics of subway station under earthquakes. To this end, seismic waves are transformed into equivalent nodal loads on viscoelastic artificial boundaries using theories and methods of wave motion. The calculation formulas for equivalent nodal loads of SV waves incident at any angle are established, and ANSYS' APDL program compiles to automatically generate the viscoelastic artificial boundary and input the seismic loads. A finite element model of soil-subway station interaction was established, and the seismic response characteristics of a two-story three-span subway station under different incidence angles of SV waves were investigated using the above seismic input method. The results indicate that the incidence angle of seismic waves has a significant impact on the seismic response of subway station. Inclined incidence of seismic waves causes non-uniform loading and deformation of the subway station. Specifically, a small angle leads to predominantly transverse shear deformation, while a large angle causes mainly vertical shear deformation. The inclined incidence of seismic waves significantly increases the vertical acceleration of the subway station, with the effect becoming more pronounced as the angle increases. Additionally, special attention should be given to the joints between the structural slab and the side wall, slab and center column, as well as the two ends of the center column as they are vulnerable areas during earthquakes and require careful consideration in seismic design.

2.
ChemSusChem ; 17(4): e202301331, 2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-37853262

RESUMEN

Due to the intrinsic safety and cost effectiveness, aqueous Zn-ion batteries (AZIBs) are considered a promising candidate for future energy storage systems. However, the widespread implementation of AZIBs faces significant obstacles due to various undesirable side reactions, including hydrogen evolution reaction (HER), corrosion, and uncontrolled dendrite growth at the anodes. Here, 4-hydroxybenzoic acid sodium salt (PHB) is employed in the ZnSO4 electrolyte to enable highly-reversible zinc anodes. PHB has a greater tendency to bind with the Zn surface, resulting in increased steric effects within the electrolyte. As a result, it hinders the direct interaction between anode and water while facilitating the uniform plating of Zn2+ . Zn/Zn batteries with PHB additives realized more than 1600 h stable cycling life under 1 mA cm-2 and 1 mAh cm-2 . Moreover, Zn/Cu batteries with PHB additives achieved a reversible plating/stripping process for over 500 cycles with high average CE of 98.6 %. In addition, the assembled Zn/NH4 V4 O10 batteries with PHB additive yielded 80.5 mAh g-1 after 1000 cycles at 10 A g-1 . The inexpensive and effective application of PHB as an electrolyte additive has the potential to significantly enhance the stability and dependability of ZIBs.

3.
Animals (Basel) ; 13(11)2023 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-37889633

RESUMEN

The objective of this study was to investigate the PPBRs of EF and CF in the plasma of yellow catfish, grass carp, and largemouth bass at different temperatures with different concentrations. A fast and simple ultrafiltration method was used to determine the PPBRs of EF and CF. Results showed that PPBRs of EF decreased from 37.71% to 9.66%, from 46.10% to 13.52%, and from 43.90% to 4.36% in the plasma of yellow catfish with the increase of concentration from 15 to 25 °C. The same trends of PPBRs of EF were presented in the plasma of grass carp and largemouth bass. In comparison to the data at the same concentration of EF at disparate temperatures, the PPBRs of EF at a concentration of 1 µg/mL increased from 37.71% to 46.10% and then decreased to 43.90% in the plasma of yellow catfish with elevated temperature from 15 to 25 °C. There is no obvious regularity with the rise of temperature, and the same phenomenon also were found in other concentrations and species. Meanwhile, the PPBRs of CF also decreased in the three species with the rise in concentration. Under the consistent concentration, the temperature-dependent regularities were not found in the PPBRs of CF. Overall, the increased concentration reduced the PPBRs of EF and CF in the plasma of three fish species, and the alteration in temperature only has a certain effect on the PPBRs of EF and CF.

4.
Animals (Basel) ; 13(16)2023 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-37627363

RESUMEN

The objective of the present study was to investigate the residue depletion of EF and CF in yellow catfish to estimate its WTs in plasma and tissues after multiple oral doses for 3 days at 20 mg/kg at 15, 20, and 25 °C. Samples were collected at pre-designed time points after oral doses. A validated method was performed to quantify EF and CF in plasma and tissues by high-performance liquid chromatography. Statistical differences were conducted using one-way ANOVA analysis. According to the maximum residue limit of China and Europe considering 95% percentile with 95% confidence, the WTs were estimated to be 44, 72, 66, 99, and 95 days at 15 °C; 32, 66, 65, 86, and 73 days at 20 °C; and 32, 61, 64, 55, and 59 days at 25 °C in the plasma, muscle and skin, gill, liver, and kidney, respectively. We found that increased temperature shortened the WTs in plasma and tissues. Therefore, this study can help the risk assessment of EF in aquatic products for human health at different temperatures to avoid residue violation.

5.
Food Res Int ; 166: 112604, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36914350

RESUMEN

Doxycycline is an important medicine in aquaculture for treating fish diseases. However, its excess use causes residue exceeding to threaten human health. So, this study aimed to estimate a reliable withdrawal time (WT) of doxycycline (DC) in crayfish (Procambarus clarkii) based on statistical approaches and conduct a risk assessment for human health in the natural environment. Samples were collected at predetermined time points and determined by high-performance liquid chromatography. A novel statistical method was used to process the data of residue concentration. The homogeneity and linearity of the regressed line of data were evaluated by Bartlett's, Cochran's, and F tests. Outliers were excluded by establishing the standardized residual versus their cumulative frequency distribution on a normal probability scale. The calculated WT was 43 days in muscle of crayfish based on China and European stipulations. After 43 days, estimated daily intakes of DC were ranged from 0.022 to 0.052 µg/kg/d. Hazard Quotients were ranged from 0.007 to 0.014, which were far less than 1. These results indicated that established WT could avoid health risks for humans resulting from DC's residue in crayfish.


Asunto(s)
Astacoidea , Doxiciclina , Animales , Humanos , Astacoidea/química , Alimentos Marinos/análisis , Ambiente , Medición de Riesgo
6.
Front Neurol ; 14: 1094066, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36779050

RESUMEN

Objective: Although balloon-assisted techniques are valuable in aneurysm clipping, repeated angiography and fluoroscopy are required to understand the location and shape of the balloon. This study investigated the value of visualization balloon occlusion-assisted techniques in aneurysm hybridization procedures. Methods: We propose a visualization balloon technique that injects methylene blue into the balloon, allowing it to be well visualized under a microscope without repeated angiography. This study retrospects the medical records of 17 large or giant paraclinoid aneurysms treated by a visualization balloon occlusion-assisted technique in a hybrid operating room. Intraoperative surgical techniques, postoperative complications, and immediate and long-term angiographic findings are highlighted. Results: All 17 patients had safe and successful aneurysm clipping surgery with complete angiographic occlusion. Under the microscope, the balloon injected with methylene blue is visible through the arterial wall. The position and shape of the balloon can be monitored in real time without repeated angiography and fluoroscopic guidance. Two cases of intraoperative visualization balloon shift and slip into the aneurysm cavity were detected in time, and there were no cases of balloon misclipping or difficult removal. Of 17 patients, four patients (23.5%) experienced short-term complications, including pulmonary infection (11.8%), abducens nerve paralysis (5.9%), and thalamus hemorrhage (5.9%). The rate of vision recovery among patients with previous visual deficits was 70% (7 of 10 patients). The mean follow-up duration was 32.76 months. No aneurysms or neurological deficits recurred among all patients who completed the follow-up. Conclusion: Our study indicates that microsurgical clipping with the visualization balloon occlusion-assisted technique seems to be a safe and effective method for patients with large or giant paraclinoid aneurysms to reduce the surgical difficulty and simplify the operation process of microsurgical treatment alone.

7.
Artículo en Inglés | MEDLINE | ID: mdl-36709862

RESUMEN

The objective of this study was to examine the pharmacokinetic (PK) properties of enrofloxacin (EF) and its metabolite, ciprofloxacin (CF), in yellow catfish (Pelteobagrus fulvidraco) after a single oral dose of EF at 20 mg/kg at 20, 25, and 30 °C. Samples were collected at pre-designed time points and determined by high-performance liquid chromatography with a fluorescent detector. Results showed that most concentrations of EF and CF in plasma and tissues at the same time point at different temperatures were statistically significant. With the increase in temperature, the terminal half-life (T1/2λz) of EF and CF was first reduced from 20 to 25 °C but elevated from 25 to 30 °C in plasma, muscle + skin, gill, liver, and kidney, respectively. The area under the plasma concentration-time curves (AUClast) of EF were all decreased in plasma, muscle + skin, and gill except for that of EF in the liver and kidney. However, the AUClast and the apparent metabolic rate of CF were exhibited first elevated and then decreased trend. The apparent volume of distribution (Vz_F) of EF was first reduced from 20 to 25 °C but increased at 30 °C. The apparent total body clearance (CL_F) of EF was increased from 0.15 to 0.32 L/h·kg with the temperature elevation. These indicated that increased temperature markedly affected the PKs of EF and CF in yellow catfish. Through in-depth analysis, the EF dosage of 20 mg/kg is appropriate to use in yellow catfish at 20 and 25 °C but 30 °C.


Asunto(s)
Bagres , Ciprofloxacina , Animales , Enrofloxacina , Ciprofloxacina/farmacocinética , Temperatura , Fluoroquinolonas/análisis , Fluoroquinolonas/farmacocinética , Cinética , Administración Oral
8.
Front Oncol ; 12: 918296, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36267985

RESUMEN

Background: The setup accuracy plays an extremely important role in the local control of tumors. The purpose of this study is to verify the feasibility of "Sphere-Mask" Optical Positioning System (S-M_OPS) for fast and accurate setup. Methods: From 2016 to 2021, we used S-M_OPS to supervise 15441 fractions in 1981patients (with the cancer in intracalvarium, nasopharynx, esophagus, lung, liver, abdomen or cervix) undergoing intensity-modulated radiation therapy (IMRT), and recorded the data such as registration time and mask deformation. Then, we used S-M_OPS, laser line and cone beam computed tomography (CBCT) for co-setup in 277 fractions, and recorded laser line-guided setup errors and S-M_OPS-guided setup errors with CBCT-guided setup result as the standard. Results: S-M_OPS supervision results: The average time for laser line-guided setup was 31.75s. 12.8% of the reference points had an average deviation of more than 2 mm and 5.2% of the reference points had an average deviation of more than 3 mm. Co-setup results: The average time for S-M_OPS-guided setup was 7.47s, and average time for CBCT-guided setup was 228.84s (including time for CBCT scan and manual verification). In the LAT (left/right), VRT (superior/inferior) and LNG (anterior/posterior) directions, laser line-guided setup errors (mean±SD) were -0.21±3.13mm, 1.02±2.76mm and 2.22±4.26mm respectively; the 95% confidence intervals (95% CIs) of laser line-guided setup errors were -6.35 to 5.93mm, -4.39 to 6.43mm and -6.14 to 10.58mm respectively; S-M_OPS-guided setup errors were 0.12±1.91mm, 1.02±1.81mm and -0.10±2.25mm respectively; the 95% CIs of S-M_OPS-guided setup errors were -3.86 to 3.62mm, -2.53 to 4.57mm and -4.51 to 4.31mm respectively. Conclusion: S-M_OPS can greatly improve setup accuracy and stability compared with laser line-guided setup. Furthermore, S-M_OPS can provide comparable setup accuracy to CBCT in less setup time.

9.
Appl Opt ; 60(18): 5399-5404, 2021 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-34263779

RESUMEN

We numerically investigated a sandwiched photonic crystal fiber (S-PCF) based on triangular lattice air holes that can be used for broadband dispersion compensation. By adjusting two layers of air holes diameter in the cladding, the S-PCF performs a large negative dispersion curve that can compensate for the dispersion of a standard single-mode fiber (SMF). The kappa value of the proposed PCF is also consistent with that of the SMF at the wavelength of 1.55 µm. In addition, the dispersion compensation multiple reaches up to 25.37. We have successfully obtained an effective compensated dispersion with the value of -0.5 to +0.1ps/nm/km in the wavelength of 1.46-1.67 µm, which covers the S+C+L+U wavelength bands. Moreover, we considered the manufacturing tolerance of the dispersion and effective compensated dispersion with ±2% and ±5% variation.

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