Graphene based new physics phenomena are leading to a variety of stimulating graphene-based photonic devices. In this study, the enhancement of surface evanescent field by graphene cylindrical ...cladding is observed, for the first time, by using a graphene-coated microfiber multi-mode interferometer (GMMI). It is found theoretically and experimentally that the light transmitting in the fiber core is efficiently dragged by the graphene, hence significantly enhancing the evanescent fields, and subsequently improving the sensitivity of the hybrid waveguide. The experimental results for gas sensing verified the theoretical prediction, and ultra-high sensitivities of ~0.1 ppm for NH(3) gas detection and ~0.2 ppm for H(2)O vapor detection are achieved, which could be used for trace analysis. The enhancement of surface evanescent field induced by graphene may pave a new way for developing novel graphene-based all-fiber devices with compactness, low cost, and temperature immunity.
Lithium is an activator of β-catenin signaling, and β-catenin mediates bone acquisition in response to mechanical loading in the bone. We tested the hypothesis that lithium enhances new bone ...formation during midpalatal suture expansion. Forty-eight Wistar rats with or without suture expansion were gavage-fed daily with lithium chloride or sodium chloride. We labeled the rats with bromodeoxyuridine to evaluate the proliferation and differentiation of the osteoprogenitors. Lithium increased β-catenin expression and cell proliferation in expanding sutures. Initial delay in the differentiation of osteoprogenitors into mature osteoblasts by lithium treatment corresponded with expansion of pre-osteoblasts, which preceded the increase of new bone formation in the suture. These results suggested that β-catenin regulates proliferation of osteoprogenitors and maturation of osteoblasts during midpalatal suture expansion osteogenesis, and that lithium enhances bone regeneration by elevating β-catenin expression. Lithium treatment could be a pharmaceutical aid to improve the stability of orthodontic treatment like rapid palatal expansion.
Abstract
X-ray scattering (XRS), x-ray absorption near-edge structure (XANES) and extended x-ray absorption fine structure (EXAFS) spectroscopic techniques were used to study the electronic and ...atomic structures of the high-quality Sr
3
Ir
4
Sn
13
(SIS) single crystal below and above the transition temperature (T
*
≈ 147 K). The evolution of a series of modulated satellite peaks below the transition temperature in the XRS experiment indicated the formation of a possible charge density wave (CDW) in the (110) plane. The EXAFS phase derivative analysis supports the CDW-like formation by revealing different bond distances Sn
1(2)
-Sn
2
below and above T
*
in the (110) plane. XANES spectra at the Ir
L
3
-edge and Sn
K
-edge demonstrated an increase (decrease) in the unoccupied (occupied) density of Ir 5
d
-derived states and a nearly constant density of Sn 5
p
-derived states at temperatures T < T
*
in the (110) plane. These observations clearly suggest that the Ir 5
d
-derived states are closely related to the anomalous resistivity transition. Accordingly, a close relationship exists between local electronic and atomic structures and the CDW-like phase in the SIS single crystal.
The adsorption and separation of CH3OH/H2O and CO2/CH4 in Zn(BDC)(TED)0.5 (BDC = benzenedicarboxylate, TED = triethylenediamine) are investigated by integrating experiment and simulation. ...Zn(BDC)(TED)0.5 is a highly hydrophobic metal−organic framework (MOF) with interlacing channels. The simulated isotherms of CH3OH and H2O are in fairly good agreement with experimental results. While H2O adsorption in Zn(BDC)(TED)0.5 is vanishingly small, CH3OH shows a much stronger adsorption. The selectivity of CH3OH over H2O is approximately 20 at low pressures and the selectivity decreases with increasing pressure. From the density distributions and structural analysis, it is found that CH3OH interacts strongly with the metal oxides, particularly at low pressures. The isotherms of CO2 and CH4 from simulation match well with experimental data. As a nonpolar molecule, CO2 exhibits different favorable sites from polar CH3OH. At low pressures, CO2 is located preferentially near the BDC linkers. As pressure increases, CO2 is proximal to the metal oxides and TED linkers. The selectivity of CO2 over CH4 increases as a function of pressure, with a magnitude similar to that in most neutral MOFs. H2O has a negligible effect on the selectivity of CO2/CH4. In addition, the simulated adsorption isotherm of n-hexane is in accord with experiment. This work provides a quantitative understanding at the molecular level for adsorption behavior in Zn(BDC)(TED)0.5 and suggests that Zn(BDC)(TED)0.5 is a good candidate for the separation of alcohol/water mixtures and alcohol-based liquid fuels.
Abstract In this study, PbZr 0.52 Ti 0.48 O 3 /PbZrO 3 (PZT/PZ) multilayer films were prepared on SiO 2 /Si substrate buffered with LaNiO 3 (LNO) thin films, and then annealed at different ...temperatures by rapid thermal annealing (RTA) technology. The phase structures, microstructures, and electrical properties of the obtained PZT/PZ multilayer films were studied. According to the results of XRD and SEM, it was found that the PZ films with perovskite phase were obtained by annealing at 650 °C firstly. The PZT films on crystallized PZ films were in amorphous phase after annealing at 450 °C, in pyrochlore phase after annealing at 550 °C, and finally in perovskite phase at annealing temperature higher than 600 °C. The multilayer films with the PZT films annealed at 550 °C exhibited linear hysteresis loops, and such films showed the enhanced energy storage density of 31.6 J cm −3 and the energy storage efficiency of 66.9% at a high breakdown field strength of 2475 kV cm −1 . The experimental results proved that the phase structure of the PZT/PZ multilayer films can be regulated by different annealing temperatures, which could further enhance the energy storage performance of the PZT/PZ multilayer films.
BACKGROUND The importance of early intravenous (IV) antibiotic use for Mycobacterium abscessus complex lung diseases (MABC-LD) treatment remains unknown. METHODS A retrospective multi-centre
...observational study was conducted in Taiwan. Patients who were diagnosed with and received treatment for MABC-LD from January 2007 to April 2021 were included. Treatment outcome was defined as modified microbiological cure of MABC-LD. RESULTS Of
the 89 enrolled patients, 34 (38.2%) received IV antibiotics as part of the treatment regimen. The median time to IV initiation was 1 day (IQR 1-49); 24 (70.6%) of these patients received IV agents within 4 weeks, defined as early-use. Forty-two (47.2%) patients achieved modified microbiological
cure. In the multivariable logistic analysis, early IV antibiotic use was an independent factor associated with modified microbiological cure (aOR 5.32, 95% CI 1.66-17.00), whereas high radiological score (aOR 0.86, 95% CI 0.73-1.00) demonstrated negative association. CONCLUSIONS In
the present study, early use of effective IV antibiotic was prescribed in a low percentage (27%) for MABC-LD. By contrast, early IV antibiotic use was correlated with higher microbiological cure than were late or non-use. Future larger and prospective studies are needed to validate the association.
Abstract Background The recipient's hepatic vascular anatomy is essential in living-donor liver transplantation (LDLT). Magnetic resonance angiographic inflow-sensitive inversion recovery (IFIR-MRA) ...is a new noncontrast technology for vascular evaluation, particularly for those patients with renal function impairment. The purpose of this study was to improve the image quality with different blood suppression inversion time (BSP TI) settings. Methods From October 2012 to March 2013, 21 recipient candidates underwent IFIR-MRA with the use of the GE 1.5T-Discovery 450 for LDLT preoperation evaluation with different BSP TI settings. Subjective visualized image quality and depiction of hepatic arteries, portal veins, and inferior vena cava (IVC) were all evaluated on a vessel-to-vessel basis. A paired t test analysis was used to assess the difference in grading scales between the different BSP TI settings in IFIR-MRA. Results The 21 recipients (4 female, 17 male) had a mean age of 53.43 ± 11.07 years. A significant difference ( P < .001) existed in the arterial depiction scores between BSP TI 1,000 ms (3.10 ± 0.70) and BSP TI 1,400 ms (3.57 ± 0.7). There were no significant differences of quality scores in artery (3.71 ± 0.56 vs 3.48 ± 0.60), portal vein (3.57 ± 0.60 vs 3.48 ± 0.51), and IVC (2.71 ± 1.19 vs 2.76 ± 1.09), and no significant differences of depiction scores in portal vein (2.29 ± 0.46 vs 2.48 ± 0.51) and IVC (1.57 ± 0.68 vs 1.62 ± 0.15). Conclusions The images with BSP TI 1,400 ms were the most optimal for IFIR noncontrast MRA imaging in LDLT. This new technology can replace traditional contrast-enhanced MRA, especially for patients with renal function impairment.
Abstract
A new concrete recycling method is to crush demolished concrete into distinctly large recycled concrete lumps (RCLs), which are in a direct mix with fresh concrete, leading to the so-called ...compound concrete. Not only can this method decrease the recycling cost by simplifying the recycling process, it can also increase the recycling ratio. However, existing studies have demonstrated that such compound concrete is inferior to normal concrete. To improve the performance of compound concrete, an effective technique is to confine the compound concrete using fiber-reinforced polymer (FRP)–confining tubes, as demonstrated by a limited number of studies through tests on circular compound concrete columns. However, no studies have been done on FRP-confined rectangular compound concrete columns. Moreover, the possible column size effect in such columns has never been investigated; indeed, existing studies have revealed that FRP-confined rectangular normal concrete columns of different-sized specimens may exhibit obvious behavioral difference. Against this background, this paper presents the results of the first-ever experimental program on glass FRP (GFRP)–confined square compound concrete columns of three different sizes. The columns of different sizes had the same effective FRP confinement stiffness, and, therefore, the possible column size effect could be revealed. It was observed that the column size effect was obvious in the test columns in terms of compressive strength. Finally, three existing compressive strength models originally developed for FRP-confined normal concrete were evaluated using the present test results.
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