539 research outputs found
Novel Wideband Metallic Patch Antennas with Low Profile
Two planar metallic patch (MP) antennas with low profiles are investigated and compared in this paper. The MP of each antenna consists of metallic patch cells and it is centrally fed by a rectangular slot. Two modes with close resonance frequencies are excited, providing a quite wide bandwidth. The antenna principle is explained clearly through a parametric study. Simulated and measured results show that the MP antennas with profile of 0.06λ0 can obtain a 10 dB impedance bandwidth of ~32% and an average gain of ~10 dBi
Network pharmacology and UPLC-Q-TOF/MS studies on the anti-arthritic mechanism of Pterocephalus hookeri
Purpose: To investigate the mechanism underlying the anti-arthritic properties of Pterocephalus hookeri used for treatment of rheumatoid arthritis (RA).Methods: Aqueous methanol extract of P. hookeri was analyzed using UPLC-Q-TOF/MS, a Waters Acquity UPLCR BEH C18 column (2.1 × 100 mm, 1.7 μm) and gradient elution with acetonitrile-formic acid-water. Targets and related pathways were predicted by PharmMapper database and Molecule Annotation System, respectively. The network was built with Cytoscape software.Results: Forty compounds were identified, comprising 17 iridoid glycosides, 7 phenolic acids, 13 triterpenes, and 3 other compounds. A total of 38 targets and 44 pathways associated with RA were obtained. These involved mainly MAPK signaling pathway, adherens junction, and colorectal cancer.Conclusion: These results from network pharmacology suggest that P. hookeri exerts therapeutic effect on RA via multiple components, multiple targets and multiple pathways.Keywords: Pterocephalus hookeri, Rheumatoid arthritis, UPLC-Q-TOF/MS, Chemical composition, Network pharmacolog
A study on non-invasive prenatal screening for the detection of aneuploidy
Objectives: To explore the feasibility of clinical application of non-invasive prenatal screening to detect aneuploidy diseases.
Material and methods: A total of 14,574 singleton pregnant women who underwent Non-invasive prenatal testing (NIPT) in the Southern Hospital from 2015 to June 2017 were selected, and 6471 pregnant women with twin pregnancy who underwent NIPT in the laboratory of Bei Rui He Kang Southern Hospital from June 2016 to October 2017 were included in this study. We analyzed NIPT screening efficiency (sensitivity, specificity) in twin pregnancies and singleton pregnancies, compared the positive detection rate of NIPT in patients with or without clinical symptoms. All NIPT high-risk results were validated by karyotyping, which were further verified by the follow-up physical examination of the neonatal.
Results: A total of 68 cases of twin pregnancy abnormalities were detected by NIPT, including 18 cases of trisomy 21, 6 cases of trisomy 18, 1 case of trisomy 13, 39 cases of Spinocerebellar ataxias (SCAs), and 4 cases of other chromosomal abnormalities. The sensitivity for trisomy 21, 18, and 13 and sex chromosome abnormality was 100%; the specificity for trisomy 21, 18, and 13 and sex chromosome abnormality was 99.97%, 99.95%, 99.97%, and 99.91% respectively. The screening efficiency was similar to that of singleton pregnancy, indicating that the NIPT technology in our laboratory for screening for aneuploidy diseases in twin pregnancy has reached the accuracy level of singleton pregnancy screening. There was a statistical difference between the risk group and the non-risk group in pregnant women with singleton pregnancy. The screening efficiency of NIPT was higher in pregnant women in the risk group, which implies that the clinical application of NIPT is inclined to detect high-risk group.
Conclusions: Non-invasive prenatal testing (NIPT) is a rapid and safe screening method with high efficiency. Non-invasive prenatal testing (NIPT) is used for the screening of aneuploidy in twin pregnancy. The efficiency is similar to that of singleton pregnancy, indicating the feasibility of clinical application. However, the efficiency of NIPT screening tends to favor the detection in high-risk groups
Graphdiyne-metal contacts and graphdiyne transistors
Graphdiyne is prepared on metal surface, and making devices out of it also
inevitably involves contact with metals. Using density functional theory with
dispersion correction, we systematically studied for the first time the
interfacial properties of graphdiyne contacting with a series of metals (Al,
Ag, Cu, Au, Ir, Pt, Ni, and Pd). Graphdiyne is in an n-type Ohmic or
quasi-Ohmic contact with Al, Ag, and Cu, while it is in a Schottky contact with
Au (at source/drain interface), Pd, Pt, Ni, and Ir (at source/drain-channel
interface), with high Schottky barrier heights of 0.39, 0.21 (n-type), 0.30,
0.41, and 0.45 (p-type) eV, respectively. A graphdiyne field effect transistor
(FET) with Al electrodes is simulated by using quantum transport calculations.
This device exhibits an on-off ratio up to 104 and a very large on-state
current of 1.3 * 104 mA/mm in a 10 nm channel length. Thus, a new prospect is
opened up for graphdiyne in high performance nanoscale devices.Comment: 27 pages, 9 figure
In Situ Reconstruction of High‐Entropy Heterostructure Catalysts for Stable Oxygen Evolution Electrocatalysis under Industrial Conditions
info:eu-repo/semantics/publishedVersio
Review on risk assessments of dammed lakes
As one type of natural disaster, dammed lakes pose a serious threat to the safety of lives and properties downstream. Scientific risk assessments of dammed lakes are key for pre-disaster prevention and post-disaster rescue. However, due to the lack of basic information and uncertainty surrounding materials and loads, risk assessments of dammed lakes are more complex than those of artificial reservoir dams, and comprehensive assessment methods are lacking. Based on the evolution of dammed lake hazard chains, starting with the concept of a dammed lake risk assessment, this paper focused on six aspects: worldwide dammed lake databases, hazard assessments for landslide dams, breach mechanisms and breach processes, flood routing after landslide dam breaching, loss assessments, and risk mitigation measures. A comprehensive review was conducted on the qualitative and quantitative risk assessment methods around the world, as well as future outlooks
Superconductivity and Charge-density-wave-like Transition in Th2Cu4As5
We report the synthesis, crystal structure, and physical properties of a
novel ternary compound, ThCuAs. The material crystallizes in a
tetragonal structure with lattice parameters {\AA} and
{\AA}. Its structure can be described as an alternating stacking
of fluorite-type ThAs layers with antifluorite-type double-layered
CuAs slabs. The measurement of electrical resistivity, magnetic
susceptibility and specific heat reveals that ThCuAs undergoes bulk
superconducting transition at 4.2 K. Moreover, all these physical quantities
exhibit anomalies at 48 K, where the Hall coefficient change the sign. These
findings suggest a charge-density-wave-like (CDW) transition, making
ThCuAs a rare example for studying the interplay between CDW and
superconductivity.Comment: 11 pages, 6 figures, and 1 tabl
A clinical evaluation of amlexanox oral adhesive pellicles in the treatment of recurrent aphthous stomatitis and comparison with amlexanox oral tablets: a randomized, placebo controlled, blinded, multicenter clinical trial
<p>Abstract</p> <p>Background</p> <p>Amlexanox has been developed as a 5 percent topical oral paste for the treatment of patients with recurrent aphthous stomatitis (RAS) in most European countries. However, it is not yet available in China and has not been generally accepted in clinical treatment. The aim of this study was to explore the effectiveness of amlexanox oral adhesive pellicles in the treatment of minor recurrent aphthous ulcers, and compare the results with those of amlexanox oral adhesive tablets in order to analyse the difference between the two dosage forms of amlexanox.</p> <p>Methods</p> <p>We performed a randomized, blinded, placebo-controlled, parallel, multicenter clinical study. A total of 216 patients with minor recurrent aphthous ulcers (MiRAU) were recruited and randomized to amlexanox pellicles or placebo pellicles. Pellicles were consecutively applied four times per day, for five days. The size and pain level of ulcers were measured and recorded on treatment days 0, 4 and 6. Finally, the results were compared with those of our previous 104 cases treated with amlexanox tablets.</p> <p>Results</p> <p>Amlexanox oral adhesive pellicles significantly reduced ulcer size (P= 0.017 for day 4, P=0.038 for day 6) and alleviated ulcer pain (P=0.021 for day 4, P=0.036 for day 6). No significant difference was observed in the treatment effectiveness between the pellicle and tablet form of amlexanox.</p> <p>Conclusions</p> <p>Amlexanox oral adhesive pellicles are as effective and safe as amlexanox oral adhesive tablets in the treatment of MiRAU for this Chinese cohort. However, pellicles seem to be more comfortable to use when compared with the dosage form of tablets. Therefore, in clinical practice, amlexanox oral adhesive pellicles may be a better choice for RAS patients.</p> <p>Trials registration</p> <p>Nederlands Trial Register NTR1727.</p
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