Luminescence and temperature-sensing properties of Li+, Na+, or K+, Tm3+, and Yb3+ co-doped Bi2WO6 phosphors

A series of Li+, Na+, or K+, Tm3+, and Yb3+ co-doped Bi2WO6 upconversion phosphors were prepared by a high-temperature solid-phase method at 800°C for 3 h. X-ray diffraction showed that Li+, Na+, K+, Tm3+, and Yb3+ doping did not affect the orthorhombic structure of the Bi2WO6 matrix. Scanning electron microscopy images of the Bi2WO6:1% Tm3+, 6% Yb3+ and 1% Li+, 1% Na+, or 1% K+-doped Bi2WO6:1% Tm3+, 6% Yb3+ samples reveal irregular particles with a 0.5–5 µm particle size range; upon Na+ or K+ doping, the particle size increases and the particle surface becomes smooth. EDS analysis shows that the above ions are well incorporated into the powder particles. At 298 K, the relative temperature sensitivities are 0.00144, 0.0016, 0.0024, and 0.0018 K−1 for the 1% Tm3+, 6% Yb3+:Bi2WO6 samples without alkali metal ions and doped with 1% Li+, 1% Na+, or 1% K+ based on the thermally coupled energy level 3F3/3F2 characterization temperature. However, under the same conditions, when using the nonthermally coupled level 3F3/1G4 characterization temperature, the relative temperature sensitivities of these four samples are 0.0378, 0.0166, 0.046, and 0.0257 K−1, increasing by 26.3, 10.3, 19.1, and 13.9 times, respectively. The relative temperature sensitivities of the 1% Na+, 1% Tm3+, and 6% Yb3+:Bi2WO6 samples are the highest at 298 K

Lumbosacral Transitional Vertebra Contributed to Lumbar Spine Degeneration: An MR Study of Clinical Patients

We aimed to comprehensively characterize degenerative findings associated with various types of lumbosacral transitional vertebra (LSTV) on magnetic resonance images. Three hundred and fifty patients with LSTV (52.3 ± 10.9 years), including 182 Castellvi type I, 107 type II, 43 type III, and 18 type IV, and 179 controls without LSTV (50.6 ± 13.1 years), were studied. Discs, endplates, and posterior vertebral structures were assessed and compared to those of controls for the most caudal three discs on MRIs. There were no differences in degenerative findings between patients with type I LSTV and controls. For types III and IV, the transitional discs had smaller sizes, lower Pfirrmann scores, and lower rates of disc bulging (2.3% and 5.6% vs. 39.1%), osteophytes (2.3% vs. 15.1%), disc herniation (2.3% and 5.6% vs. 31.8%), and Modic changes (2.3% and 5.6% vs. 16.8%) than controls. However, the cranial discs had more severe Pfirrmann scores, disc narrowing and spinal canal narrowing, and greater rates of disc herniation (41.9% and 50.0% vs. 25.7%), endplate defects (27.9% and 33.3% vs. 14.4%) and spondylolisthesis (18.6% vs. 7.3%) than controls. Type II LSTV was associated with degenerative findings in the cranial segments but to a lesser degree, as compared with type III/IV LSTV. Thus, Castellvi type III/IV LSTV predisposed the adjacent spinal components to degeneration and protected the transitional discs. Type II LSTV had significant effects in promoting transitional and adjacent disc degeneration. Type I LSTV was not related to spinal degeneration

Au(I)/Ag(I)-Catalyzed Cascade Approach for the Synthesis of Benzo[4,5]imidazo[1,2‑<i>c</i>]pyrrolo[1,2‑<i>a</i>]quinazolinones

An efficient and facile Au­(I)/Ag­(I)-catalyzed cascade method has been developed for one-pot synthesis of the complex polycyclic heterocycles benzo­[4,5]­imidazo­[1,2-<i>c</i>]­pyrrolo­[1,2-<i>a</i>]­quinazolinone derivatives through treatment of the substituted 2-(1<i>H</i>-benzo­[<i>d</i>]­imidazol-2-yl)­anilines with 4-pentynoic acid or 5-hexynoic acid. The strategy features a Au­(I)/Ag­(I)-catalyzed one-pot cascade process involving the formation of three new C–N bonds in high yields, and with broad a substrate scope

Clinical and Biomechanical Study of Laminoplasty for Thoracic and Lumbar Intradural Tumors

(1) Background: Primary intraspinal tumors account for 2–15% of all central nervous system (CNS) tumors. Most intraspinal tumors are benign, and about 40% of them occur intradurally, for which early surgery is the preferred treatment. Laminectomy with pedicle screw fixation is the conventional surgical treatment. However, laminectomy with pedicle screw fixation is likely to reduce the spinal range of motion (ROM), with many other complications, although it can maintain the stability of the spine. The aim of this study is to determine whether laminoplasty as a new surgical approach for thoracic and lumbar intradural tumors is superior to laminectomy in preserving spinal ROM, maintaining spinal stability and reducing postoperative complications. (2) Methods: We retrospectively analyzed 50 patients who received intradural tumor resection, including 23 who received traditional laminectomy with pedicle screw fixation and 27 who received new laminoplasty. Spinal ROM was evaluated by lumbar flexion/extension radiograph and biomechanical evaluation. Spinal stability was evaluated by imaging observations of the spinal Cobb angle and laminar bone fusion. Postoperative complications were evaluated according to cerebrospinal fluid (CSF) leakage and the length of hospital stay. (3) Results: Compared with the laminectomy group, patients in the laminoplasty group exhibited a better spinal ROM (31.6 ± 12.0° vs. 21.7 ± 11.8°, p = 0.013), a smaller Cobb angle (9.6 ± 4.3 vs. 12.5 ± 5.3, p = 0.034), a lower incidence of CSF leakage (4/14.8% vs. 11/47.8%, p = 0.015), and a shorter length of hospital stay (13.1 ± 1.8 vs. 15.1 ± 2.3 days, p = 0.001). Most patients in the laminoplasty group had satisfactory bone fusion. The biomechanical experiment also demonstrated that spinal ROM in laminoplasty was larger than that in the laminectomy group. (4) Conclusions: Compared with the traditional surgery, the new laminoplasty surgery can better maintain the stability of the spine, preserve spinal ROM, and reduce postoperative complications. It is a surgical method that can be clinically popularized

Au(I)/Ag(I)-Catalyzed Cascade Approach for the Synthesis of Benzo[4,5]imidazo[1,2‑<i>c</i>]pyrrolo[1,2‑<i>a</i>]quinazolinones

An efficient and facile Au­(I)/Ag­(I)-catalyzed cascade method has been developed for one-pot synthesis of the complex polycyclic heterocycles benzo­[4,5]­imidazo­[1,2-<i>c</i>]­pyrrolo­[1,2-<i>a</i>]­quinazolinone derivatives through treatment of the substituted 2-(1<i>H</i>-benzo­[<i>d</i>]­imidazol-2-yl)­anilines with 4-pentynoic acid or 5-hexynoic acid. The strategy features a Au­(I)/Ag­(I)-catalyzed one-pot cascade process involving the formation of three new C–N bonds in high yields, and with broad a substrate scope