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1.
Dalton Trans ; 51(30): 11295-11301, 2022 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-35819169

RESUMO

The incorporation of Sc3+ can stabilize calcite-phase LuBO3:Ce3+ to grow large-sized single crystals but leads to the significant degradation of scintillation performance. In the present work, alkali metal ion (A+ = Li+, Na+, K+)-incorporated (Lu, A, Sc)BO3:Ce was rapidly synthesized in batches via a high-throughput sol-gel method. The aliovalent substitution of Lu3+ with A+ is balanced by the generation of oxygen vacancies by forming complexes. Thanks to the increased oxygen vacancies, the luminescence and XEL intensity of (Lu, Li, Sc)BO3:Ce are significantly enhanced by 2.2 times and 1.9 times, respectively. Further, the incorporation of A+ is attributed to the improved transition efficiency of charge carriers. The prepared scintillation screen fabricated with LASBO:Ce and PMMA shows that the spatial resolution can reach 8.6 lp mm-1, indicating its potential application in efficient and low-cost non-destructive X-ray detection. This work is of great significance in improving the luminescence and scintillation performance of (Lu, Sc)BO3:Ce single crystals and thin films and their application in the scintillation field.

2.
J Clin Med ; 11(6)2022 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-35330025

RESUMO

Obese patients are predisposed to rapid oxygen desaturation during tracheal intubation. We aimed to compare the risk of desaturation between high-flow nasal oxygenation (HFNO) and classical facemask oxygenation (FMO) during rapid sequence intubation for elective surgery in obese patients. Adults with a body mass index ≥30 kg·m−2 undergoing laparoscopic sleeve gastrectomy at a medical center were randomized into the HFNO group (n = 40) and FMO group (n = 40). In the HFNO group, patients used a high-flow nasal cannula to receive 30 to 50 L·min−1 flow of heated and humidified 100% oxygen. In the FMO group, patients received a fitting facemask with 15 L·min−1 flow of 100% oxygen. After 5-min preoxygenation, rapid sequence intubation was performed. The primary outcome was arterial desaturation during intubation, defined as a peripheral capillary oxygen saturation (SpO2) <92%. The risk of peri-intubation desaturation was significantly lower in the HFNO group compared to the FMO group; absolute risk reduction: 0.20 (95% confidence interval: 0.05−0.35, p = 0.0122); number needed to treat: 5. The lowest SpO2 during intubation was significantly increased by HFNO (median 99%, interquartile range: 97−100) compared to FMO (96, 92−100, p = 0.0150). HFNO achieved a higher partial pressure of arterial oxygen (PaO2) compared to FMO, with medians of 476 mmHg (interquartile range: 390−541) and 397 (351−456, p = 0.0010), respectively. There was no difference in patients' comfort level between groups. Compared with standard FMO, HFNO with apneic oxygenation reduced arterial desaturation during tracheal intubation and enhanced PaO2 among patients with obesity.

3.
Inorg Chem ; 61(10): 4302-4311, 2022 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-35212526

RESUMO

Mechanoluminescence materials that emit light under mechanical stimulation have attracted widespread attention in sensing, anticounterfeiting, and imaging applications. In this study, a series of Sr1-xBixZnSO (0.001 ≤ x ≤ 0.1) samples was synthesized by the method of high temperature solid-state reaction. It is worth noting that the distortion degree of the SrO3S3 octahedron was increased with increasing Bi3+ concentration, and the color manipulated Sr1-xBixZnSO which can emit different photoluminescence (blue to dark blue and finally red) and mechanoluminescence (orange to red) colors is obtained. Moreover, the deep traps can stably store and provide electronic supplements in shallow traps released under mechanical stimulation. Therefore, devices made of SrZnSO:Bi3+ phosphor and polydimethylsiloxane (PDMS) can be used as thermo-mechano-opto three-mode anticounterfeiting. The ML intensity is linear to the external load and can be utilized for stress sensing or imaging.

4.
Dalton Trans ; 50(32): 11130-11136, 2021 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-34323902

RESUMO

A series of Bi3+ and Mn2+ co-doped CaZnOS phosphors with a tunable emission color have been synthesized by a high temperature solid-state reaction method. Their crystal structure, spectroscopic properties, energy transfer and thermal quenching have been investigated systematically. An intense blue-green emission band at 485 nm and a red emission band at 616 nm were observed at an excitation wavelength of 375 nm, owing to the 3P1,0→1S0 transition of Bi3+ and the 4T1(4G) →6A1(6S) transition of Mn2+, respectively. The tunable color from blue-green, white light to red light can be obtained by varying the Mn2+ ion concentration from 0.005 to 0.015 in CaZnOS:Bi3+. The decay time decreased from 642 to 273 ns with the Mn2+ ion concentration x increasing from 0.005 to 0.015, and the energy transfer efficiency ηT can reach up to 65% in the CaZnOS:Bi3+,0.015Mn2+ phosphor. As the temperature increases from 300 to 420 K, the emission intensity is maintained at 67%, and the activation energy Ea is estimated to be 0.28 eV. An LED fabricated using CaZnOS:Bi3+,0.01Mn2+ exhibited the chromaticity coordinates and corrected color temperature (CCT) of (0.338, 0.364) and 4655 K, respectively. These results validate the promising applications of the CaZnOS:Bi3+,Mn2+ phosphor in UV white LEDs.

5.
J Clin Med ; 11(1)2021 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-35011903

RESUMO

Obesity increases the risk of prolonged emergence from general anesthesia due to the delayed release of anesthetic agents from body fat. This trial aimed to evaluate the effects of sevoflurane and desflurane along with anesthetic depth monitoring on emergence time from anesthesia in obese patients. Adults with a body mass index ≥ 30 kg·m-2 undergoing laparoscopic sleeve gastrectomy at a medical center were randomized into four groups: sevoflurane or desflurane anesthesia with or without M-Entropy guidance on anesthetic depth in a ratio of 1:1:1:1. In the M-Entropy guidance groups, the dosage of sevoflurane and desflurane was adjusted to achieve response and state entropy values between 40 and 60 during surgery. In the non-M-Entropy guidance groups, the dosage of anesthetics was titrated according to clinical signs. Primary outcome was time to spontaneous eye opening. A total of 80 participants were randomized. Compared to sevoflurane, desflurane anesthesia significantly reduced the time to spontaneous eye opening [mean difference (MD): -129 s; 95% confidence interval (CI): -211, -46], obeying commands (-160; -243, -77), tracheal extubation (-172; -266, -78), and leaving operating room (-148; -243, -54). M-Entropy guidance further reduced time to eye opening (MD: -142 s; 99.2% CI: -276, -8), tracheal extubation (-199; -379, -19), and leaving operating room (-190; -358, -23) in the desflurane but not the sevoflurane group. M-Entropy guidance significantly reduced the risk of agitation during emergence, i.e., risk difference: -0.275 (95% CI: -0.464, -0.086); and number needed to treat: 4. Compared to sevoflurane, using desflurane to maintain general anesthesia accelerated the return of consciousness in obese patients. M-Entropy guidance further hastened awakening in patients using desflurane and prevented emergence agitation.

6.
ACS Appl Mater Interfaces ; 12(18): 20849-20858, 2020 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-32233356

RESUMO

Carbon dots (CDs) as new fluorescent materials with excellent fluorescence properties have shown enormous potential applications, especially in anticounterfeiting and cell imaging. Herein, nitrogen-doped CDs (NCDs) with excellent biocompatibility were prepared by a simple thermal sintering method. An extremely large red shift (∼130 nm) of the emission peak was observed when the excitation wavelength changes from 355 to 550 nm, indicating that NCDs are excellent fluorescent labeling materials for multiple cell imaging. On the other hand, NCDs showed obvious changes of emission intensity and peak position when the temperature increased from 223 to 323 K and the pH values changed from 1 to 13, respectively, which has been demonstrated by the "horse" pattern printed with NCD water-soluble fluorescent inks. The nontoxic NCDs dispersed in a multiple matrix are highly sensitive to excitation wavelength, temperature, and pH, indicating their great potential application in multiple anticounterfeiting and multiple cell imaging.


Assuntos
Corantes Fluorescentes/química , Fraude/prevenção & controle , Tinta , Pontos Quânticos/química , Alginatos/química , Carbono/química , Carbono/efeitos da radiação , Carbono/toxicidade , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/efeitos da radiação , Corantes Fluorescentes/toxicidade , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Microscopia Confocal , Microscopia de Fluorescência , Nitrogênio/química , Nitrogênio/efeitos da radiação , Nitrogênio/toxicidade , Pontos Quânticos/efeitos da radiação , Pontos Quânticos/toxicidade , Temperatura
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