Tunable Unidirectional Sound Propagation through a Sonic-Crystal-Based Acoustic Diode

Nonreciprocal wave propagation typically requires strong nonlinear materials to break time reversal symmetry. Here, we utilized a sonic-crystal-based acoustic diode that had broken spatial inversion symmetry and experimentally realized sound unidirectional transmission in this acoustic diode. These novel phenomena are attributed to different mode transitions as well as their associated different energy conversion efficiencies among different diffraction orders at two sides of the diode. This nonreciprocal sound transmission could be systematically controlled by simply mechanically rotating the square rods of the sonic crystal. Different from nonreciprocity due to the nonlinear acoustic effect and broken time reversal symmetry, this new model leads to a one-way effect with higher efficiency, broader bandwidth, and much less power consumption, showing promising applications in various sound devices

The level of IL-35 in the circulation of patients with Graves’ disease

Introduction: The aim of this study was to explore the potential role of IL-35 in Graves’ disease (GD). Material and methods: A total of 142 GD patients including 80 newly onset patients, 52 refractory patients and 10 remission patients and 70 normal controls (NCs) were recruited. The messenger RNA (mRNA) expressions of P35 and Epstein-Barr-virus-induced gene 3 (Ebi3) were measured by quantitative reverse transcription polymerase chain reaction (qRT-PCR). Serum level of IL-35 was measured by enzyme-linked immunosorbent assay (ELISA). Results: The expression of IL-35mRNA in new onset GD and refractory GD were both significantly higher than NC. Comparison between remission GD and NC showed no significant difference (p > 0.05). A significant increase of Ebi3mRNA expression was observed in new onset GD compared with remission GD (p = 0.030). The new onset GD showed a tendency for increased expression of serum IL-35 but without significant difference. No correlation between IL-35 expression and clinic parameters was found. Conclusions: Our preliminary observations indicate that IL-35 and CD4+P35+Ebi3+T cells may be involved in the pathogenesis of GD

Strong Photoluminescence Enhancement of MoS2 through Defect Engineering and Oxygen Bonding

We report on a strong photoluminescence (PL) enhancement of monolayer MoS2 through defect engineering and oxygen bonding. Micro- PL and Raman images clearly reveal that the PL enhancement occurs at cracks/defects formed during high temperature vacuum annealing. The PL enhancement at crack/defect sites could be as high as thousands of times after considering the laser spot size. The main reasons of such huge PL enhancement include: (1) the oxygen chemical adsorption induced heavy p doping and the conversion from trion to exciton; (2) the suppression of non-radiative recombination of excitons at defect sites as verified by low temperature PL measurements. First principle calculations reveal a strong binding energy of ~2.395 eV for oxygen molecule adsorbed on an S vacancy of MoS2. The chemical adsorbed oxygen also provides a much more effective charge transfer (0.997 electrons per O2) compared to physical adsorbed oxygen on ideal MoS2 surface. We also demonstrate that the defect engineering and oxygen bonding could be easily realized by oxygen plasma irradiation. X-ray photoelectron spectroscopy further confirms the formation of Mo-O bonding. Our results provide a new route for modulating the optical properties of two dimensional semiconductors. The strong and stable PL from defects sites of MoS2 may have promising applications in optoelectronic devices.Comment: 23 pages, 9 figures, to appear in ACS Nan

Competition and cooperation of sulfate reducing bacteria and five other bacteria during oil production

Embargo until March 18, 2023Effective control of sulfate-reducing bacteria (SRB) will help reduce economic losses and prevent threats to human health during the oil production. In this study, the responses of SRB to environmental variables and some functional microorganisms (including denitrifying bacteria (DNB), methanogenic bacteria (MGB), saprophytic bacteria (SPB), zymophyte bacteria (ZPB), and iron bacteria (IB)), during oil production processes were investigated to improve our understanding of how to control SRB abundance. Correlation analyses demonstrated that nitrate and redox potential exihibited significant inhibitory effects on the growth and reproduction of SRB and redox potential (0.175, P < 0.01) had a stronger effect than NO3− (0.0817, P < 0.05). PCA analysis demonstrated a clear division of the bacteria into two clusters, cluster 1 consisted of SRB, SPB and IB, while cluster 2 consisted of DNB, MGB and ZPB. Cooperation was apparent for SRB with SPB and IB, while competition was apparent for SRB with DNB, MGB and ZPB. These results provide new insights to possible solutions to control SRB growth in the oilfield environment, including addition of nitrate and nitrite, to promote the growth of denitrifying bacteria, thereby suppressing the growth of SRB.acceptedVersio