Fabrication of broadband antireflection coatings using wavelength-indirect broadband optical monitoring

Multi-layer optical coatings with complex spectrum requirements, such as multi-band pass filters, notch filters, ultra-broadband antireflection coating and etc., whose working wavelength is out of monitoring wavelength range, are difficult to be fabricated using direct broadband optical monitoring (BBOM). In this paper, a broadband antireflection (AR) coating in the wavelength range from 1300 nm to 2000 nm at 45 incident was designed and deposited by dual ion beam sputtering (DIBS). Ta2O5 and SiO2 were chosen as high and low refractive index coating materials, respectively. The optimized coating structure contains 4 non-quarter-wave (QW) layers. In order to obtain high transmittance, the most important is to realize the thickness accurate control. Due to the limitation of the monitoring wavelength range, which is only from 450 nm to 1000 nm, a wavelength-indirect broadband optical monitoring strategy was successfully employed to control the layers thickness during the deposition process. At last, a good agreement between theoretical and measured transmittance is obtained. The maximum error (the first layer) is only about 5.3% and the minimum error (the third layer) is about -0.25% base on the results of reverse engineering analysis. (C) 2017 Elsevier GmbH. All rights reserved

Study on the Properties of 1319 nm Ultra-High Reflector Deposited by Electron Beam Evaporation Assisted by an Energetic RF Ion Source

Ultra-high reflectors, working as a critical optical component, has been widely applied as a cavity mirror in fine optical systems such as laser gyro, F-P interferometer, etc. For decades, ion beam sputtering (IBS) technology, which can deposit ultra-low loss and dense layers, has been commonly believed to be the only and irreplaceable method to fabricate ultra-high reflectors. Thus, reports on other methods are rare and a reflectivity above 99.99% obtained by evaporation technology (including ion assisted evaporation) has not been seen yet. In the present study, an energetic radio frequency (RF) ion source was introduced during the electron beam evaporation process, which improved the layer quality dramatically. An ultra-high reflector at 1319 nm with reflectivity of 99.992% (measured by cavity-ring down method) was successfully deposited on a phi 100 mm x 25 mm single crystal silicon substrate whose surface roughness was approximately 0.420 nm. The surface figure of the reflector was accurately controlled superior to 1/6 lambda (lambda = 632.8 nm). The measured absorption was approximately 3-5 ppm and the calculated scatter based on surface roughness measurement was approximately 6.64 ppm. Total loss of the reflector was systematically discussed. This study showed that it is possible to apply electron beam evaporation in ultra-high reflector manufacture and the method is capable of depositing reflectors with an aperture larger than phi 600 mm which is the maximum capacity of current IBS technology

Transparent and water repellent ceria film grown by atomic layer deposition

Transparent and hydrophobic ceria film was fabricated by atomic layer deposition (ALD). The ceria coatings were characterized by goniometry, atomic force microscopy, X-ray photoelectron spectroscopy and variable angles spectroscopic ellipsometry. The hydrophobicity of the ceria coatings was investigated with water contact angles achieving as high as 105 degrees. The effect of annealing or surface relaxation on the hydrophobicity was studied. Surface chemistry analysis of the ceria surfaces was carried out to understand the surface treatment towards the wettability of the ALD coatings. The proposed ALD ceria film offers the advantages of hydrophobic coatings covering fine optical lens such as band-pass filter. (C) 2017 Published by Elsevier B.V

METTL14 enhances the m6A modification level of lncRNA MSTRG.292666.16 to promote the progression of non-small cell lung cancer

Abstract Background m6A modification has close connection with the occurrence, development, and prognosis of tumors. This study aimed to explore the roles of m6A modification and its related mechanisms in non-small cell lung cancer (NSCLC). Methods NSCLC tissues and their corresponding para-cancerous tissues were collected to determine the m6A levels of total RNA/lncRNAs and the expression of m6A modification-related genes/lncRNAs. Then, A549 cells were transfected with si-METTL14 or oe-METTL14, and the cell transfection efficiency was assessed. Subsequently, the viability, apoptosis, cell colony formation, migration and invasion of the different cells were determined. Finally, the nude mouse tumorigenicity experiments were performed to observe the effects of METTL14 in vivo. Results Compared to the para-NSCLC tissues, the m6A level and METTL14 expression were both significantly increased in the NSCLC tissues (P < 0.05). Based on the expression of METTL14 in the different cell lines, A549 cells were chosen for further experiments. Then, the A549 cells with METTL14 knockdown and overexpression were successfully established, as well as it was found that METTL14 knockdown could inhibit the viability, colony formation, migration, and invasion of A549 cells, while facilitate their apoptosis. In vivo experiments also showed that METTL14 knockdown could inhibit tumor formation and growth. Additionally, the m6A level of MSTRG.292666.16 was higher in the NSCLC tissues; and after METTL14 knockdown, the expression and m6A level of MSTRG.292666.16 were both significantly reduced in A549 cells, and vice versa. Conclusion METTL14 may promote the progression of NSCLC through up-regulating MSTRG.292666.16 and enhance its m6A modification level

Cancer-Related Triplets of mRNA-lncRNA-miRNA Revealed by Integrative Network in Uterine Corpus Endometrial Carcinoma

The regulation of transcriptome expression level is a complex process involving multiple-level interactions among molecules such as protein coding RNA (mRNA), long noncoding RNA (lncRNA), and microRNA (miRNA), which are essential for the transcriptome stability and maintenance and regulation of body homeostasis. The availability of multilevel expression data enables a comprehensive view of the regulatory network. In this study, we analyzed the coding and noncoding gene expression profiles of 301 patients with uterine corpus endometrial carcinoma (UCEC). A new method was proposed to construct a genome-wide integrative network based on variance inflation factor (VIF) regression method. The cross-regulation relations of mRNA, lncRNA, and miRNA were then selected based on clique-searching algorithm from the network, when any two molecules of the three were shown as interacting according to the integrative network. Such relation, which we call the mRNA-lncRNA-miRNA triplet, demonstrated the complexity in transcriptome regulation process. Finally, six UCEC-related triplets were selected in which the mRNA participates in endometrial carcinoma pathway, such as CDH1 and TP53. The multi-type RNAs are proved to be cross-regulated as to each of the six triplets according to literature. All the triplets demonstrated the association with the initiation and progression of UCEC. Our method provides a comprehensive strategy for the investigation of transcriptome regulation mechanism

Relationship between ID1 and EGFR-TKI Resistance in Non-small Cell Lung Cancer

Background and objective Non-small cell lung cancer (NSCLC) presents the highest morbidity and mortality among malignant tumors worldwide. The overall effective rate of epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI) is 30% to 40%, and PFS (progression-free sruvival) is 12 months. However, EGFR-TKI resistance is typical in clinical observations, and this phenomenon significantly affects tumor suppression. To overcome this resistance, a new prognostic factor associated with lung cancer drug resistance should be discovered. This study investigated the relationship between the inhibitor of differentiation 1 (ID1) and non-small cell lung cancer EGFR-TKI resistance in vivo and in vitro to determine any statistical significance and discuss the underlying mechanism. Methods Western blot and qRT-PCR were used to quantify the expression of ID1 in lung cancer. IHC was used to detect the expression of ID1 in pathological tissues (lung cancer tissues and adjacent tissues). MTT was used to detect cell proliferation, in which the cells were treated with gefitinib after being transfected by ID1 slow virus vector. Lung cancer cells were inoculated in nude mice until the tumor diameter grew to certain measurement. Gefitinib treatment was started, and the tumor volume was estimated. Results ID1 was highly expressed in NSCLC (P<0.05). Both ID1 expression and drug resistance of EGFR-TKI in NSCLC were positively correlated (P<0.05). The treatment group with gefitinib showed obviously less expression than the control group. Conclusion ID1 is highly expressed in NSCLC. ID1 expression was positively related to drug resistance of EGFR-TKI in NSCLC. Gefitinib can be used to effectively treat NSCLC, and the mechanism may be associated with an increased level of STAT3 phosphorylation

Effects of Annealing on Residual Stress in Ta2O5 Films Deposited by Dual Ion Beam Sputtering

Optical coatings deposited by the dual ion beam sputtering (DIBS) method usually show high compressive stress, which results in severe wavefront deformation of optical elements. Annealing post-treatment has been widely used to control the residual stress of optical coatings. However, the effect of annealing on the stress of Ta2O5 films deposited by the IBS method has not been reported in detail. In this study, different thicknesses of Ta2O5 films were deposited by IBS and annealed at different temperatures from 473 to 973 K in air, and the effect of annealing on the stress of Ta2O5 films was investigated. The as-deposited Ta2O5 films deposited by IBS show high compressive stress, which are about 160 MPa. The compressive stress decreases linearly with the increasing temperature, and the wavefront deformation of Ta2O5 films increases linearly with film thickness (within 20 &mu;m) at the same annealing temperature. When the temperature rises to 591 K, Ta2O5 films with zero-stress can be obtained. Ta2O5 films show tensile stress instead of compressive stress with further increasing annealing temperature, and the tensile stress increases with increasing temperature. Meanwhile, with the increasing annealing temperature, the refractive index of Ta2O5 film decreases, indicating the decreasing packing density. The atomic force microscope (AFM) test results show that surface roughness of Ta2O5 films slowly increases with the increasing of annealing temperature. Moreover, X-ray photoelectron spectroscopy (XPS) analysis shows that the Ta in Ta2O5 films can be further oxidized with increasing annealing temperature, namely, the absorption of Ta2O5 film can be reduced. X-ray diffraction (XRD) analysis shows that the annealing temperature should be below 923 K to maintain the amorphous structure of the Ta2O5 film

Further Optimized Design of a Nested Rotate Sextupole Permanent Magnet Lens for the Focusing of Pulsed Neutrons

A compact nested rotate sextupole permanent magnet (Nest-Rot-SPM) lens was designed for the focusing of pulsed neutrons. It is based on the working conditions of the Very Small Angle Neutron Scattering (VSANS) instrument at the China Spallation Neutron Source (CSNS), and is expected to focus a neutron pulse from 6 Å to 10.5 Å, without chromatic aberration. Three hurdles must be addressed, i.e., the tremendous torque, the heat deposition, and the synchronization with the neutron pulse, respectively. The bore diameter and segment length of the lens are optimized using a formula analysis of the key parameters and model simulations of the torque and heat deposition. A twin torque canceling design is used to reduce the torque to one-third of its original value, or even lower. The goal of this project is to take the device into practical use in the VSANS at the CSNS

Further Optimized Design of a Nested Rotate Sextupole Permanent Magnet Lens for the Focusing of Pulsed Neutrons

A compact nested rotate sextupole permanent magnet (Nest-Rot-SPM) lens was designed for the focusing of pulsed neutrons. It is based on the working conditions of the Very Small Angle Neutron Scattering (VSANS) instrument at the China Spallation Neutron Source (CSNS), and is expected to focus a neutron pulse from 6 &Aring; to 10.5 &Aring;, without chromatic aberration. Three hurdles must be addressed, i.e., the tremendous torque, the heat deposition, and the synchronization with the neutron pulse, respectively. The bore diameter and segment length of the lens are optimized using a formula analysis of the key parameters and model simulations of the torque and heat deposition. A twin torque canceling design is used to reduce the torque to one-third of its original value, or even lower. The goal of this project is to take the device into practical use in the VSANS at the CSNS