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1.
Materials (Basel) ; 16(24)2023 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-38138836

RESUMEN

The heterogeneity of concrete is a major challenge for acoustic emission monitoring. A method of active-passive joint acoustic emission monitoring considering the heterogeneity of concrete is presented herein, and the time-frequency-space multi-parameter response characteristics of active and passive acoustic emission signals were studied in relation to the damage evolution of concrete. This method provides an idea of evaluating the damage state of concrete more actively and quantitatively than traditional methods. The results show that the microscopic damage model of concrete based on the acoustic emission penetrating wave velocity and amplitude is in agreement with the damage process of concrete. The standard deviation of the wave velocity up to 1000 m/s and the change rate of the amplitude up to -0.66 can be adopted as two signs that the load of concrete reached 70% of the ultimate load. The time-of-arrival localization based on variable velocity was used to correct the acoustic emission localization results, and the localization accuracy was increased by 44.74%. The damage process of concrete undergoes diverse changes; that is, the distribution of damage changes from heterogeneous to homogeneous and then back to heterogeneous. Hence, it is necessary for researchers to consider the heterogeneity of concrete when using acoustic emission monitoring. The active-passive joint acoustic emission monitoring is an effective method.

2.
Opt Lett ; 48(22): 5935-5938, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37966756

RESUMEN

We present the design and fabrication of an on-chip FBG interrogator based on arrayed waveguide grating (AWG) technology. The spectral overlap between adjacent channels in the integrated AWG is significantly enhanced through a combination approach involving the reduction of the output waveguide spacing and an increase in the input waveguide width. As a result of these design choices, our AWG demonstrates excellent spectral consistency, with spectral cross talk exceeding 30 dB. The interrogator seamlessly combining optical and circuitry components achieves full integration and enables a wide range of interrogation wavelengths, including C-band and L-band. With an interrogation range extending up to 80 nm, it theoretically has the capacity to simultaneously interrogate the wavelengths of 20 FBG sensors. Experimental findings demonstrate an absolute interrogation accuracy of less than 2 pm for the fully integrated interrogator. With its compact size, cost-effectiveness, exceptional precision, and ease of integration, the proposed interrogator holds a substantial promise for widespread application in the realm of FBG sensing.

3.
World J Clin Cases ; 11(27): 6455-6475, 2023 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-37900219

RESUMEN

BACKGROUND: Radical resection offers the only hope for the long-term survival of patients with gallbladder carcinoma (GBC) above the T1b stage. However, whether it should be performed under laparoscopy for GBC is still controversial. AIM: To compare laparoscopic radical resection (LRR) with traditional open radical resection (ORR) in managing GBC. METHODS: A comprehensive search of online databases, including Medline (PubMed), Cochrane Library, and Web of Science, was conducted to identify comparative studies involving LRR and ORR in GBCs till March 2023. A meta-analysis was subsequently performed. RESULTS: A total of 18 retrospective studies were identified. In the long-term prognosis, the LRR group was comparable with the ORR group in terms of overall survival and tumor-free survival (TFS). LRR showed superiority in terms of TFS in the T2/tumor-node-metastasis (TNM) Ⅱ stage subgroup vs the ORR group (P = 0.04). In the short-term prognosis, the LRR group had superiority over the ORR group in the postoperative length of stay (POLS) (P < 0.001). The sensitivity analysis showed that all pooled results were robust. CONCLUSION: The meta-analysis results show that LRR is not inferior to ORR in all measured outcomes and is even superior in the TFS of patients with stage T2/TNM Ⅱ disease and POLS. Surgeons with sufficient laparoscopic experience can perform LRR as an alternative surgical strategy to ORR.

4.
Front Oncol ; 13: 1186378, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37469411

RESUMEN

Objectives: Although guidelines recommend extended cholecystectomy for T2 gallbladder cancer (GBC), the optimal hepatectomy strategy remains controversial. The study aims to compare the prognosis of T2 GBC patients who underwent wedge resection (WR) versus segment IVb and V resection (SR) of the liver. Methods: A specific search of online databases was performed from May 2001 to February 2023. The postoperative efficacy outcomes were synthesized and meta-analyses were conducted. Results: A total of 9 studies involving 2,086 (SR = 627, WR = 1,459) patients were included in the study. The primary outcomes included disease-free survival (DFS) and overall survival (OS). For DFS, the 1-year DFS was statistically higher in patients undergoing SR than WR [risk ratio (RR) = 1.07, 95% confidence interval (CI) = 1.02-1.13, P = 0.007]. The 3-year DFS (P = 0.95), 5-year DFS (P = 0.77), and hazard ratio (HR) of DFS (P = 0.72) were similar between the two groups. However, the 3-year OS was significantly lower in patients who underwent SR than WR [RR = 0.90, 95% CI = 0.82-0.99, P = 0.03]. Moreover, SR had a higher hazard HR of OS [HR = 1.33, 95% CI = 1.01-1.75, P = 0.04]. No significant difference was found in 1-year (P = 0.32) and 5-year (P = 0.9) OS. For secondary outcomes, patients who received SR tended to develop postoperative complications (POC) [RR = 1.90, 95% CI = 1.00-3.60, P = 0.05]. In addition, no significant differences in intrahepatic recurrence (P = 0.12) were observed. Conclusions: In conclusion, SR can improve the prognosis of T2 GBC patients in DFS. In contrast to WR, the high HR and complications associated with SR cannot be neglected. Therefore, surgeons should evaluate the condition of the patients and take their surgical skills into account when selecting SR. Systematic review registration: https://www.crd.york.ac.uk/prospero/, identifier, CRD42022362974.

5.
Foods ; 12(1)2022 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-36613295

RESUMEN

The usage of tea polyphenols (TPs) as a natural food additive into non-fermented frozen dough (NFFD) has rarely been investigated, and results have been controversial. Hence, this study investigated the effect of TPs at various levels (0, 0.5, 1, and 2%) on the quality of NFFD stored from 0 to 4 weeks. The rheological characteristics, water state, protein, and its microstructure were analyzed by DSC, LF-NMR, SDS-PAGE, FT-IR, and SEM, respectively. Results showed that the 0.5% TP group delayed the deterioration of protein and inhibited the water migration in dough throughout the whole frozen storage period. In addition, the 0.5% TP group enhanced the rheological properties of NFFD and stabilized the sulfhydryl content and the secondary structure in the gluten network. On the contrary, opposite phenomena were found in the 1 and 2% TP groups, which might be due to the induction of excess hydroxyl groups from TPs. In conclusion, our results suggested that a proper addition of TPs, but not an excessive amount (>1%), exhibited beneficial effects in maintaining the quality of NFFD during the 4-week frozen storage. Moreover, this paper elucidated the mechanism of TPs in influencing the protein structure and water state of NFFD during storage and provided new insight into its application in dough-based foods.

6.
Macromol Biosci ; 20(3): e1900382, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32058665

RESUMEN

The feasible fabrication of nerve guidance conduits (NGCs) with good biological performance is important for translation in clinics. In this study, poly(d,l-lactide-co-caprolactone) (PLCL) films loaded with various amounts (wt; 5%, 15%, 25%) of methylcobalamin (MeCbl) are prepared, and are further rolled and sutured to obtain MeCbl-loaded NGCs. The MeCbl can be released in a sustainable manner up to 21 days. The proliferation and elongation of Schwann cells, and the proliferation of Neuro2a cells are enhanced on these MeCbl-loaded films. The MeCbl-loaded NGCs are implanted into rats to induce the regeneration of 10 mm amputated sciatic nerve defects, showing the ability to facilitate the recovery of motor and sensory function, and to promote myelination in peripheral nerve regeneration. In particular, the 15% MeCbl-loaded PLCL conduit exhibits the most satisfactory recovery of sciatic nerves in rats with the largest diameter and thickest myelinated fibers.


Asunto(s)
Células Inmovilizadas , Regeneración Nerviosa/efectos de los fármacos , Traumatismos de los Nervios Periféricos , Poliésteres , Células de Schwann , Nervio Ciático , Vitamina B 12/análogos & derivados , Animales , Línea Celular , Células Inmovilizadas/metabolismo , Células Inmovilizadas/patología , Células Inmovilizadas/trasplante , Regeneración Tisular Dirigida , Traumatismos de los Nervios Periféricos/metabolismo , Traumatismos de los Nervios Periféricos/patología , Traumatismos de los Nervios Periféricos/terapia , Poliésteres/química , Poliésteres/farmacología , Ratas , Ratas Sprague-Dawley , Células de Schwann/metabolismo , Células de Schwann/patología , Células de Schwann/trasplante , Nervio Ciático/lesiones , Nervio Ciático/patología , Nervio Ciático/fisiología , Vitamina B 12/química , Vitamina B 12/farmacología
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