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The coupling and interplay between magnon and phonon are important topics for spintronics and magnonics. In this work we studied the nonlinear magnon-phonon coupling in CoF 2 . First-principles calculations demonstrate that the antiferromagnetic resonance magnon drives a phonon with B 1g character; the oscillating driving force has a frequency twice of that of the magnon. Comparing with similar materials indicates a strong correlation between the strength of nonlinear magnon-phonon coupling and the orbital magnetic moment of the magnetic ion. This work pave the way for theoretical study of nonlinear magnon-phonon coupling., (© 2024 IOP Publishing Ltd.)

The vicinity to a two-dimensional magnetic material provides a simple and effective way to break the valley degeneracy of transition-metal dichalcogenides because of the magnetic proximity effect. Based on first-principles calculations, we study the band structure of a MoS 2 /CrI 3 van der Waals heterostructure and its manipulation by vertical electric fields. A huge valley splitting of about 19.60 meV, equivalent to an external magnetic fields of about 89.0 T can be generated by an electric field of 0.115 V Å -1 . The electric field causes discontinuous changes in the valley splitting. The electric field drives the bands of MoS 2 across those of CrI 3 . At the critical electric fields, the interlayer orbital hybridization leads to the energy level repulsion and an abrupt exchange of the band index. We also study the effect of interlayer distance on the valley splitting and observe a more significant electric field modulation. This work deepens our understanding on the interfacial magnetic proximity effect as a result of the orbital hybridization across the van der Waals gap., (© 2021 IOP Publishing Ltd.)

The van der Waals ferromagnetic material VI 3 is a magnetic Mott insulator. In this work, we investigate the effects of isotropic and anisotropic pressure on the atomic structure and the electronic structure of VI 3 using the first-principles method. The in-plane strain induces structural distortion and breaks the three-fold rotational symmetry of the lattice. Both the in-plane and out-of-plane strain widen the conduction and the valence bands, reduce the energy band gap and drive VI 3 from a semiconductor to a three-dimensional metal. The structural distortion is not the cause of insulator-to-metal transition. Calculations of the magnetocrystalline anisotropy energy indicate an easy-axis to easy-plane transition when the pressure is higher than 2 GPa. The ferromagnetic Curie temperature falls from 63 K at 0 GPa to 25 K at 6 GPa., (© 2021 IOP Publishing Ltd.)

Objective: To verify the accuracy and effectiveness of Goldengate high-throughput deafness gene chip in detecting the patients with enlarged vestibular aqueduct syndrome(EVAS), and to provide a reference for genetic detection strategy of EVAS. Methods: From August 2016 to February 2018, 15 patients with EVAS and 60 normal controls were detected by Goldengate high-throughput deafness detection chip developed by our team, and the results were verified by Sanger sequencing. SLC26A4 gene sequencing was carried out in all the patients with EVAS. Results: 12/15 of patients with EVAS were detected mutations of SLC26A4 gene. Nine mutations were detected by chip detection and SLC26A4 gene direct sequencing, seven of which were detected by both methods. The chip could detect 93.33%(28/30) of the allele information provided by SLC26A4 gene direct sequencing. In addition to SLC26A4 gene, mutations of GJB2 , PCDH15 , TMC1 , MYO6 and mitochondrial genes were detected in 15 patients with EVAS. These results were verified by Sanger sequencing. Conclusion: Goldengate high-throughput deafness gene chip possesses the traits of wide coverage and high accuracy, which can be used as a preliminary detection method for patients with EVAS.

Graphene-based and metal-based surface plasmon polariton (SPP) waveguides have attracted intense research interest because they can be used as basic components to propagate electromagnetic (EM) waves in future optical integrated systems. We propose a directional coupler, which can couple EM energy from a multilayer-graphene-based cylindrical long-range SPP waveguide to a metal-based cylindrical hybrid SPP waveguide in the mid-infrared range. This coupler exhibits relatively low coupling length, high coupling efficiency, low insertion loss, and high extinction ratio after adjustment of the wave vector mismatch of the two waveguides. Moreover, this coupler is tolerant to practical fabrication errors like misalignment of graphene layres, and can effectively work in the range of Fermi energy Ef > 0.6 eV when the mobility of graphene varies from 10000 to 800 cm 2 /Vs. Hence, the coupler offers potential applications in signal routing and information exchange between graphene-based and metal-based SPP waveguides in photonic integrated circuits.

Understanding the photoexcited carrier-relaxation actions in ultrasmall black phosphorus quantum dots (BPQDs) will play a crucial role in the fields of electronics and optoelectronics. Herein, we report the ultraviolet (UV) saturable absorption and ultrafast photoexcited carrier-relaxation dynamics of BPQDs. The ultrasmall BPQDs are synthesized using a facile liquid-exfoliation method and possess a diameter of 3.8 ± 0.6 nm and a thickness of 1.5 ± 0.4 nm. Femtosecond open-aperture (OA) Z-scan measurements showed typical saturable absorption properties in the UV band. A negative nonlinear optical (NLO) absorption coefficient of -(1.4 ± 0.3) × 10 -3 cm GW -1 and a saturable intensity of 6.6 ± 1.3 GW cm -2 were determined. Using a degenerate pump-probe technique, an ultrafast photoexcited carrier-recombination time was observed in the range of 216-305 fs, which was 3 orders of magnitude faster than that of BP nanosheets. Such an ultrafast relaxation component may be attributable to the edge- and step-mediated recombination and was confirmed by our density functional theory (DFT) calculations. This work provides fundamental insight into the underlying mechanism of the photoexcited carrier relaxation dynamic action in BPQDs which can enable UV photonic devices.

Primary Intestinal lymphangiectasia (PIL) is a common cause of protein losing enteropathy (PLE). It will affect enter-hepatic circulation of lipid-soluble vitamin, and absorption of electrolytes, cause malnutrition related osteomalacia or osteoporosis. While seldom health care workers noted to assess and treat osteomalacia or osteoporosis in PIL. Here we report a related case. We found increased parathyroid hormone, decreased 25(OH)D3, low bone mineral density, which indicated that the PIL patient had osteomalacia and/or osteoporosis. Adequate calcium and vitamin D supply can relieve the condition efficaciously. We should pay attention to osteomalacia and osteoporosis in PIL patients.

First-principles density functional theory coupled with deformation potential calculations indicate a strong width-dependent carrier mobility: for an armchair graphene ribbon whose width (i.e., number of carbons along the edge) is N = 3k, the room-temperature electron mobility is calculated to be approximately 10(6) cm(2) V(-1) s(-1) and the hole mobility approximately 10(4) cm(2) V(-1) s(-1), while for N = 3k + 1 or 3k + 2, the hole mobility is calculated to be 4-8 x 10(5) cm(2) V(-1) s(-1) and the electron mobility approximately 10(4) cm(2) V(-1) s(-1). Such alternating behavior is absent in zigzag-type graphene.

Objective: To study the safety, biodistribution, and dosimetry of myocardial perfusion imaging agent 99Tc(m)N-NOET in 10 healthy volunteers., Methods: 744-792 MBq of 99Tc(m)N-NOET was injected to each volunteer. Safety parameters and adverse event was measured in 24 hours of injection. Biodistribution was studied by whole-body imaging 1, 30 minutes, 1, 2, 4, 8, and 24 hours after the injection of 99Tc(m)N-NOET. The estimation of dosimetry was based on the standard medical internal radiation dose method using MIRDOSE 3.0 analysis program. Myocardial single photon emission computed tomography (SPECT) imaging was performed at 1 and 4 hours after injection., Results: No undesirable effects were reported by the subject during 24 hours after injection of 99Tc(m)N-NOET. No clinically significant changes were found in vital signs (heart rate, blood pressure, and electrocardiogram). No biochemical aspects and serology changes were measured. The myocardial SPECT imaging was clear. Cardiac uptake of 99Tc(m)N-NOET was as high as 2.68% at 2 hours after injection. The heart to lung ratio was more than 1 from 30 minutes after injection, reaching a maximum of 1.91 +/- 0.53 at 2 hours after injection. Radiation dosimetry calculations indicated an effective absorbed dose of 1.28 x 10(-5) Sv/MBq. The dosimetry in each main organ is lower then 50 mGy given 740 MBq of 99Tc(m)N-NOET in once imaging., Conclusions: 99Tc(m)N-NOET exhibits high cardiac uptake and low estimated effective absorbed dose. It's a safe myocardial perfusion imaging agent.

Forty patients with breast mass and 10 female controls underwent double-phase (15 min and 3 h) 99Tcm-sestamibi (MIBI) imaging. Another four post-mastectomy patients with suspected metastases underwent total body imaging at 15 min. The 99Tcm-MIBI images of all 10 female controls showed symmetrical homogeneous radioactivity in both breasts. A focal area of increased 99Tcm-MIBI uptake in the breast tumour is considered as positive. Eleven breasts of 10 patients underwent total mastectomies with lymph node dissection, with one patient having bilateral mastectomy. These 11 breast tumours were confirmed to be infiltrating ductal carcinoma. All 11 breast carcinomas had positive early and delayed phase results with the exception of one patient who had only a focal increased uptake in early phase which happened to be the smallest size of carcinoma. Focal areas of positive MIBI uptake in the axillae in 4 of 10 patients were confirmed to be metastatic carcinoma of the breast. One patient with breast carcinoma underwent mastectomy whose 99Tcm-MIBI imaging was negative. Twelve patients undergoing excisional biopsy or lumpectomy of breast resulted in 7 fibroadenomas, 2 papillomas, 1 abscess, 1 granuloma and 1 chronic inflammation. Four of 7 fibroadenomas having hypercellularity histopathologically exhibited a focal MIBI uptake on double-phase imaging. One granulomatous disease had positive early phase but faded on the delayed image. The patients with absence of MIBI uptake included 3 fibroadenomas, 2 papillomas, 1 abscess, 1 chronic inflammation and 17 fibrous hyperplasia.(ABSTRACT TRUNCATED AT 250 WORDS)