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The produced water-containing polymer brings new challenges to oil-water separation in oilfield production, yet separators with coalescing plates to remove free water have been playing an active role. In this paper, the flow-field characteristics of polymer-laden produced water in a separator with coalescing plates are analyzed using computerized mathematical methods to investigate the effects with a water content of 55%, 70%, and 85%, flow rate of 3500 m3/d, 4800 m3/d, and 6000 m3/d, and duration time of 20 min, 40 min, and 60 min on flow-field properties and separating efficiency are studied. The results show that the separating efficiency is positively correlated with water content and duration time, and duration time has the greatest improvement to the separating efficiency, but the enhancement of flow rate may reduce the separating efficiency. It is also observed that the separation efficiency of free-water reached 70.9% and the water content at the oil outlet of the separator reached 20.4% at a duration time of 60 min, when the contained polymer concentration and water content in the oil-water mixture are 500 mg/L and 70%, respectively.

The objective of this study was to compare the clinical effects of a long-pulse-width 1064-nm Nd:YAG laser-assisted ear correction model and a simple ear correction model in the treatment of congenital auricular deformities in children older than 6 weeks.A total of 129 children (179 ears) with congenital auricular deformities who were older than 2 months were included. Among them, 84 (119 ears) were treated with the ear correction model after long-pulse-width 1064-nm Nd:YAG laser irradiation (observation group) and 45 (60 ears) were treated with the ear correction model only (control group). The affected ears of the two groups were measured, the correction time was calculated, and the patients' family members filled in the satisfaction questionnaire before and after the treatment.The level of satisfaction of both groups improved after the treatment. The satisfaction level of the observation group was higher than that of the control group. Fewer days of correction were observed in the observation group than in the control group ( p0.05). The measurements of the affected ears in the two groups were significantly different after treatment. The difference after treatment of each measurement in the observation group was higher than in the control group. The therapeutic effect of the observation group was significantly better than that of the control group and the differences were statistically significant.Long-pulse-width 1064-nm Nd:YAG laser combined with the ear correction model can improve the success rate of correction of congenital auricular deformities in over-aged ears.Therapeutic, II.

With the expanding utilization of hyaluronic acid (HA) and collagen as cosmetic fillers in plastic and reconstructive surgery, complications due to their excessive use and/or irregular procedures warrant great caution. Recently, a fatal case occurred caused by a poorly regulated procedure of vaginal injection of HA and collagen. A 33-year-old female was admitted to the emergency department 3 hours after the operation with a chief complaint of dyspnea, which initiated 5 to 10 minutes after the operation. Her blood pressure remained low while dopamine pressor and fluid replacement were used. Computed tomography of the chest showed local exudation in the lower lobe of the left lung, enlargement of right atrium and ventricle, and uneven development of the bilateral inferior lobar artery with filling defects. Pulmonary computed tomography angiography and three-dimensional reconstruction showed continuous interruption of pulmonary artery branches of the posterior basal segment of the right lower lobe. Unfortunately, the clinical symptoms caused by vaginal injection aggravated rapidly and could not be effectively controlled. The patient died 9 hours after injection. Pulmonary complications after injection of cosmetic fillers are scarcely reported. Thus far, only 2 cases of HA-related pulmonary complications after vaginal injection have been described. The present case emphasizes that surgeons and other healthcare providers must be aware of the risk of serious pulmonary complications and even death associated with these 2 widely utilized injectable fillers. Level of Evidence: 5

A 300 mm×500 mm large-area echelle grating with groove density of 79 grooves/mm is fabricated for the spectrometer of the fiber array solar optical telescope (FASOT). This paper focusses on measurement methods of the grating performance. We present a method to evaluate the grating’s stray light intensity, which is measured to a level of 10−4. The directly measured grating efficiency is approximately 90% of the designed value, and an indirect measurement method based on the grating groove profile is proposed. Based on the Rayleigh criterion and the grating diffraction wavefront, a physical optics method and a geometric grating method are proposed and are used to calculate the actual grating resolving power; the calculated results exceed 95% of the grating’s theoretical resolving power. These results show that the CIOMP-6 ruling engine has sufficient precision to fabricate high-quality, large-area echelle gratings.

BACKGROUND Background: Virtual reality (VR) and augmented reality (AR) have recently become popular research themes. However, there are no published bibliometric reports that have analyzed the corresponding scientific literature in relation to the application of these technologies in surgery. Our study aims to study the research trend on virtual reality and surgery, and compare the contribution of publications from different countries, institutions, journals and authors. OBJECTIVE We used a bibliometric approach to identify and analyze the scientific literature on virtual reality and surgery during 2001-2020 form Web of Science. GraphPad Prism 6, and VOSviewer software were used to collect and analyze the publication trend in related field, revealing the popular research topics, key authors, scientific institutions, countries, and journals. METHODS The Web of Science electronic database was searched to identify relevant papers on VR research in surgery. Basic publication and citation data were acquired using the “Analyze” and “Create Citation Report” functions of the database. Complete bibliographic data were exported to VOSviewer for further analyses. Visualization maps were generated to illustrate the recurring keywords and words mentioned in the titles and abstracts. RESULTS We identified a total of 3323 publications with citation frequency of 81919 times up to August 21, 2021. The United States accounted for the largest number of publications (30.575%), 31199 of total citations as well as the highest H-index (88). The sum of publications from China ranked the fifth, while the overall citations (3257) and H-index (29) ranked the eighth and the ninth, respectively. The paper published on Annals of Surgery in 2002 had been cited for 1759times, which was the most cited papers in related field. The “system research” seemed to be the hotspot in relevant scope. CONCLUSIONS The United States made the most outstanding contribution within this important field. There is a mismatch between the quantity and quality of publications from China. Latest progress can be tracked in Annals of Surgery. Augmented reality related researches may be hotspots in the near future.

A mosaicking method for echelles is proposed. The “zero-order” and diffraction-order interference fringes of the echelle can be imaged simultaneously on the detector using a mirror–echelle structure designed. The five-dimensional mosaicking errors are divided into two categories for elimination using the “zero order” and the diffraction order. During the experiments, adjustment devices for the mosaicking errors are installed on two echelles for these two categories to avoid mechanical coupling. As theoretical analysis, we follow the experimental steps to obtain a mosaicked echelle.

A wellhead multistage bundle gas–liquid separator combining a gas–liquid cylindrical cyclone (GLCC) with multi-tube bundle components is expected to improve the gas–liquid separation performance. However, there is no unified understanding of the factors influencing the separation performance of the separator. The continuous improvement and applications of the separator are restricted. This paper evaluated the performance of the separator using a numerical simulation method. The results indicate that the separation flow field evolves to be uniform with the increased water cut when the gas–oil ratio and flow rate remain constant. Compared with a 30% water cut, the separation efficiency at a 50% water cut increased by 5.88%. When the gas–oil ratio and water cut remained constant, the swirl effect of the primary separation was enhanced. The separation efficiency increased to more than 70% when the flow rate was 15 m/s. When the flow rate and water cut remained unchanged, the pressure of the separation flow field was reduced. However, when the gas–oil ratio was greater than 160 m3/t, the flow field trace density of the secondary separation bundle was reduced, and the separation efficiency was also lower than 60%. The separation efficiency can be further improved by optimizing the number and diameter of secondary separation bundles.

Measuring mirror requirements and their impact on groove errors are related to the error compensation strategy for a ruling engine. We analyze why the measuring mirror of the CIOMP-6 engine affects the groove straightness and the grating diffraction wavefront. We study a theoretical model of the relationship between the measuring mirror’s surface shape error and the grating wavefront, propose a requirement for the measuring mirror surface shape error, and reprocess the measuring mirror. Comparative ruling experiments prove that the grating’s wavefront quality at the diffraction order along the groove direction improved significantly after reprocessing of the measuring mirror.

A method for echelle gratings tiling based on lateral shearing interferometry is proposed. Fringe patterns of the grating assembly are generated by a wedge plate. Mosaic errors can be calculated and corrected by observing the working order and its adjacent order. An experimental mosaic of two 50 mm × 50 mm , 79 grooves / mm echelles is aligned to verify the theory. The rms wavefront is better than 0.04 wavelength. Angular and translation sensitivities of less than 1 arcsec and 10 nm are achieved respectively.

Although the problems of wax deposition in multiphase transportation pipelines have been addressed and wax deposition models have been developed in recent years, the complex wax deposition paths derived from the potential variety of flow regimes in multiphase flow have not been well understood. This study presented a method for characterizing wax crystals aggregation and developed a model for describing the wax deposition path in oil−water two-phase flows. The effect of the emulsified water droplets on wax crystals aggregation in shearing flows was identified using the polarized light microscopy and image analysis method. The role of the emulsified water droplets in the wax deposition path reaching the upper side and lower side of the pipeline wall was discussed by solving the developed model which involves the possible inclination angle of the multiphase transportation pipeline. The availability of the mechanistic model was validated by the data and knowledge in the existing literature. The results indicated that the circular degree and particle size of wax crystals showed a characteristic that it first increased and then decreased with the accumulation of emulsified water droplets in shearing flow, and this transition appeared to the phase inversion point of the oil−water two-phase. The wax deposition path was complex in multiphase transportation. The velocity for wax crystals depositing to the pipeline wall decreased, and the time for wax crystals depositing to the pipeline wall extended with the existence of emulsified water droplets. This behavior became remarkable when the dispersion stability of the oil−water two-phase enhanced.

A concept for position adjustment of the diamond in a ruling engine to enable nanoscale groove positioning is proposed. Based on this concept, we fabricate a diamond carriage, design an optical path, and propose an appropriate control method. Several high-quality gratings are ruled for spectrometer or interferometer applications. After implementation of the improvements, the maximum intensity of ghosts and scattered light of the echelle grating with 79 grooves/mm is reduced to half of that before the improvement, and the highest achievable groove density is increased from 6000 grooves/mm to 8000 grooves/mm. The grating ruling results indicate that the proposed concept and the related improvements to the engine significantly improve the accuracy of the CIOMP-6 ruling engine.

In order to provide the guidance for the design and application of echelle gratings, the reason why the diffraction efficiency of the echelle grating can be improved by increasing the groove depth or reducing the apex angle is given. The polarization behaviors of gratings with different groove depths were simulated and analyzed via integral theory. To further demonstrate the polarization behavior, gratings with right and acute apex angles for classical and conical-Littrow incidence were simulated. Experimental polarization behaviors of gratings with 5.1-μm and 6.7-μm groove depths for classical incidence were obtained. The polarization degree of the echelle grating with the 6.7-μm groove depth was 6.5% at 405 nm and 2.52% at 632.8 nm, which smaller than 7.89% at 405 nm and 35.74% at 632.8 nm for the grating with a 5.1-μm groove depth. Therefore, the diffraction efficiency of an echelle grating can be improved by increasing the groove depth or reducing the apex angle, mainly because the polarization degree is restrained.

Grating tiling is an important fabrication technology for large-size gratings. However, when using grating tiling technology to form large-size echelle gratings, the interferometer cannot detect the grating's zero-order diffraction wavefront because the zero-order diffraction light of the echelle grating is weak. This prevents use of the zero-order and non-zero-order diffraction light of the grating to realize separation detection and correction of mosaic errors. To solve this problem, a new method for separation detection and correction of mosaic errors in mosaic gratings based on two detection lights with the same diffraction order but different incident angles is proposed and a mosaic error detection system is designed. Then, the correction steps for mosaic errors are summarized and the error in mosaic error detection system is analyzed. Finally, the measurement uncertainty in detecting the wavefront of the mosaic grating and the mosaic accuracy of the grating wavefront are analyzed. The uncertainty is 0.008λ (λ=632.8 nm) and the mosaic accuracy of the peak-to-valley wavefront is 0.069λ, which shows that high-precision measurements of the wavefront and high-precision mosaic of the wavefront were successfully achieved. The proposed method can be used for the mosaic of all blazed gratings.

A measuring method was studied to further improve the manufacturing accuracy of the lead screw. Firstly, factors that can axially displace the screw shaft were analyzed and a relationship between factors and axial displacement was given. The axial displacement of the screw shaft was measured using a laser interferometer, and results show that the variation amplitude of the screw-shaft axial displacement was about 80 nm while the variation period was consistent with the rotation period of the screw shaft. Next, two methods of measuring the manufacturing accuracy of the lead screw were considered: a traditional method that measures the absolute position of the nut and an improved method that measures the displacement between the nut and screw shaft. A No. 4 screw shaft was manufactured under the guidance of results obtained using the improved measuring method. Experimental measurements were then made; results show that the pitch displacement errors obtained using the traditional and improved measuring methods were 0.6 and 0.4 μm, respectively, indicating that the improved measuring method is more exact. Finally, an echelle grating ruled by a grating ruling engine that used the No. 4 screw shaft as a macro-positioning element was introduced. Its excellent parameters indirectly show that the improved measuring method has better accuracy.

A new fast algorithm for autonomous star identification in the general lost-in-space case is developed based on optimized catalog. The proposed method takes advantage of singular value decomposition method and the accuracy angular separation information. The central idea is that a unique pattern is created for each of guide star so that the pattern recognition is simple and straightforward and the index entry reaches minimum. The unique pattern is comprised of ellipticity and angular separations between pivot star and adjacent stars. The method for selecting adjacent stars of pivot star and how to rank them is presented. Three series of simulations each of which included more than ten thousand star tracker orientations were performed by dividing the entire celestial sphere into small regions. The results support the validity of the proposed method that achieves higher identification rate with 99.999%.

The groove shape characteristics of echelle gratings with high diffraction efficiency are investigated. Using the coordinate transformation method (C method), an r-2 aluminum echelle with 79 grooves/mm is optimized through rigorous numerical simulations and shows high diffraction efficiency of 76–81% in the high Littrow orders. A grating is found to be essentially an echelle if it contains a series of reflective facets with a specific tilt angle that are located far from the nonworking facet of the grating and have a deep groove depth; any groove shape that meets these conditions can be called an echelle grating. The underlying mechanism is analyzed phenomenologically using electromagnetic theory. The universal model proposed here, which represents a new cognitive understanding of the concept of the echelle, is ready for use in manufacturing applications and offers a new perspective for the fabrication of these gratings.

Poly-(ADP-ribose) polymerase inhibitors (PARPi) selectively kill breast and ovarian cancers with defects in homologous recombination (HR) caused by BRCA1/2 mutations. There is also clinical evidence for the utility of PARPi in breast and ovarian cancers without BRCA mutations, but the underlying mechanism is not clear. Here, we report that the deubiquitylating enzyme USP15 affects cancer cell response to PARPi by regulating HR. Mechanistically, USP15 is recruited to DNA double-strand breaks (DSBs) by MDC1, which requires the FHA domain of MDC1 and phosphorylated Ser678 of USP15. Subsequently, USP15 deubiquitinates BARD1 BRCT domain, and promotes BARD1-HP1γ interaction, resulting in BRCA1/BARD1 retention at DSBs. USP15 knockout mice exhibit genomic instability in vivo. Furthermore, cancer-associated USP15 mutations, with decreased USP15-BARD1 interaction, increases PARP inhibitor sensitivity in cancer cells. Thus, our results identify a novel regulator of HR, which is a potential biomarker for therapeutic treatment using PARP inhibitors in cancers., Deubiquitinases have been shown to be involved in double strand break repair pathways. Here the authors reveal that USP15 deybiquitinase plays a role in homologues recombination repair by targeting BARD1 and affecting cells response to PARP inhibitors.

Combining the mathematical relationships between the grating wavefront and surfaces with the spatial relationships between the two grating wavefront, a mathematical model of the mosaicking errors is established to mosaic gratings. The five-dimensional mosaicking errors will respectively be calculated and then removed by the adjustment mechanisms. Mosaicking experiments are performed by using two gratings. First, by using zeroth order, the longitudinal offset is calculated and removed. Second, by using the diffraction order, the in-plane angle and grating spacing are calculated and removed, while the tip and tilt angles are calculated and removed. And then a mosaic grating is obtained.

The influence of the removal depth of a silicon modification layer on grating structures and mirrors is studied. The removal depth 6-14 μm is the optimization result for Si-modified reaction-sintered silicon carbide (RS-SiC) used as mirror substrates, but the removal depth 9-12 μm is the optimization result for Si-modified RS-SiC used as grating substrates. The diffraction efficiency and stray light of the gratings fabricated in the Si-modified RS-SiC substrates with removal depth 9-12 μm is 90.5%-94% and 5.30×10-7-5.45×10-7, respectively. Additionally, the number and scale of high-reflection points can be used as the basis for judging the removal depth of the Si-modified RS-SiC used as grating substrates. These results and the regularity have guiding significance for the application of Si-modified RS-SiC as a microstructural substrate.

A swing ion-beam etching method to fabricate convex blazed gratings used in shortwave infrared hyperspectral imaging spectrometers is presented. This method solves the consistency problem of blaze angles by swing etching through the meridian direction of the gratings. The mathematical relationship of the curvature, aperture, and diffraction efficiency of convex gratings is studied to demonstrate the limitation of conventional translational lithography and the necessity of swing etching. A geometric model is built to analyze the influence of swinging speed and beam slit width on groove evolution. Convex gratings with a 45.5 gr/mm groove density, 67 mm aperture, 156.88 mm radius of curvature, and 2.2° blaze angle have been fabricated and measured where the peak and average diffraction efficiency in the shortwave infrared band reach 90% and 70%, respectively. Experimental results validate that high-efficiency convex gratings of small blaze angle and high groove consistency can be produced by swing etching, which satisfy the requirements for high spectral resolution and miniaturization of imaging spectrometers.

A field-widened spatial heterodyne Raman spectrometer with a mosaic grating structure is developed for the simultaneous sensitivity enhancement and broadband transmission Raman measurements. We optimize the etendue to maximize the signals collected from the samples by using field-widening prisms and employ two mosaic gratings to achieve broadband operation, covering 5638 cm-1 with 2.865 cm-1 spectral resolution. The signal-to-noise ratios are improved by a factor of more than 11 and show a good stability and fair repeatability. We investigate the effects of the sample thickness and outer layer depth and observe liquids, solids, mixed targets, and anti-Stokes shifts. The instrument exhibits good performance for wide-field, high-resolution broadband transmission Raman measurements.

The theoretical calculation model for a mosaic error was established based on the plane equation for a grating surface and the relationship equation for a mosaic grating surface. A mosaic grating was obtained based on this model. In the experiment, the mosaic error was calculated based on the diffraction wavefronts of two groups of mosaic gratings that were obtained simultaneously with a Zygo interferometer. The difference between the wavefront of the mosaic grating and the average wavefront of the mosaic grating element was 0 . 031 λ . The maximum far-field intensity of the mosaic grating was 90% of that without an error. This model provides a theoretical basis for the numerical mosaic between gratings. In addition, the mosaic error can be calculated with this model, and the quality of the mosaic grating can be evaluated.

In order to scan efficiently along the trace of curve-distributed off-track targets, a novel push-broom imaging method is proposed. Firstly, the trace equation is fitted to optimize the number of detectable targets. To achieve the shortest attitude maneuver time, the triaxial attitude of the satellite is solved in real time, and the TDI imaging velocity is made consistent with the direction of the trace. Finally, the ground imaging simulation is performed, and JL-1 Smart Verification Satellite is utilized to verify that the imaging temporal resolution has been improved by more than 4 times.

Reduction of groove errors on the grating wavefront caused by the refractive index of air is a critical issue in ruling grating fabrication when using an interferometer to provide position feedback. We establish a mathematical model of the relationship between the grating wavefront and the refractive index of air. We then introduce two methods to measure the air’s refractive index, analyze the effects of temperature, pressure and humidity on the grating wavefront, and use the advantages of the two methods to obtain the groove error compensation value. Comparative ruling experiments prove that grating wavefront quality is significantly improved after compensation of the groove errors caused by the refractive index of air.

As the grating area increases, the non-uniformity of the metal film thickness becomes one of the main factors affecting both the grating surface error and the wavefront of the grating diffraction order. We study the theoretical model of the relationship between the metal film thickness non-uniformity and the grating diffraction wavefront error, analyze the effects of the relevant factors on the thickness of the metal films, and determine the values of these factors using theoretical and experimental methods. We also perform a ruling experiment to verify that the wavefront quality of the grating increases with improvement in the film thickness uniformity.

Groove error is one of the most important factors affecting grating quality and spectral performance. To reduce groove error, we propose a new ruling-tool carriage system based on aerostatic guideways. We design a new blank carriage system with double piezoelectric actuators. We also propose a completely closed-loop servo-control system with a new optical measurement system that can control the position of the diamond relative to the blank. To evaluate our proposed methods, we produced several gratings, including an echelle grating with 79 grooves/mm, a grating with 768 grooves/mm, and a high-density grating with 6000 grooves/mm. The results show that our methods effectively reduce groove error in ruled gratings.

In the silicon echelle grating fabrication process, the “pseudo-mask” formed by the hydrogen bubbles generated during the etching process is the reason causing high surface roughness and poor surface quality of blazed plane. Based upon the ultrasonic mechanical effect and contact angle reduced by surfactant additive, ultrasonic vibration, isopropyl alcohol (IPA) and 2,4,7,9-Tetramethyl-5-decyne-4,7-diol (TMDD) were used to improve surface quality of 53.5 gr/mm echelle grating. The surface roughness R q is smaller than 18 nm, 7 nm and 2 nm when using ultrasonic vibration, IPA and TMDD respectively. The surface roughness R q is smaller than 5 nm and 1.5 nm respectively when combining ultrasonic vibration with IPA and TMDD. The experimental results indicated that the combination of ultrasonic agitation and surfactant additive (IPA&TMDD) could obtain a lower surface roughness of blazed plane in silicon echelle grating fabrication process.

Background The incidence of neonatal ear deformities varies widely in the literature, and the incidence of those that correct spontaneously is largely unknown. To address these questions, the authors analyzed the auricles of 1500 newborns from the Pearl River Delta within the first 7 days of life and again at 30 days of age. Methods Using a combination of direct measurement and digital image measurement, the authors measured physiognomic ear length, physiognomic ear breadth, morphologic ear length, vertical distance between head and ear, and auriculocephalic angle of the newborns. The first measurement was within 1 week of birth, whereas the second measurement was performed for the same newborns 1 month after birth. Results Among 1500 newborns, 862 had various forms of auricular deformities. The incidence of neonatal auricular deformity in the Pearl River Delta area was 57.46 percent, and the self-healing rate was 31.55 percent by the 30-day follow-up. Seven factors were found to be statistically significant: mother's delivery situation, mother's hepatitis history, abnormal pregnancy, abnormal labor, cephalopelvic disproportion, premature rupture of membranes, and neonatal weight. Birth by cesarean delivery and mother with no abnormal pregnancy or no history of hepatitis were protective factors against the newborn's auricular deformity. Conclusions Newborns have a high incidence of auricular deformities, and different types of auricular deformities have distinct incidences. Auricular deformities are caused by the interactions of a number of factors. There were large differences in the self-healing rates of different types of auricular deformities. Clinical question/level of evidence Risk, II.

Line curvature error greatly influences the quality of the diffraction wave fronts of machine-ruling gratings. To reduce the line curvature error, we propose a correction method that uses interferometric control. This method uses diffraction wave fronts of symmetrical orders to compute the mean line curvature error of the ruled grating, taking the mean line curvature error as the system line curvature error. To minimize the line curvature error of the grating, a dual-frequency laser interferometer is used as a real-time position feedback for the grating ruling stage, along with using a piezoelectric actuator to adjust the stage positioning to compensate the line curvature error. Our experiments show that the proposed method effectively reduced the peak-to-valley value of the line curvature error, improving the quality of the grating diffraction wave front.

Uniform and well-crystallized YPO4·0.8H2O and YPO4·0.8H2O:Tb3+, Eu3+ nanocrystals have been successfully synthesized by a facile hydrothermal method using trisodium citrate (Cit3−) as a “shape modifier”. X-ray diffraction (XRD), field emission-scanning electron microscopy (FE-SEM), high-resolution transmission electron microscopy (HRTEM) and photoluminescence (PL) spectra were used to characterize the samples. It was found that the pH of the initial solution was responsible for determining the shape of the final products. In addition, the YPO4·0.8H2O samples prepared by Cit3−-assisted hydrothermal synthesis exhibited an intense and bright blue emission. Characterized with Fourier transform infrared (FT-IR) spectra and electron paramagnetic resonance (EPR) spectra, the carbon-related impurities induced by trisodium citrate (Cit3−) in the hydrothermal process were confirmed and confirmed that the paramagnetic defects relating to the luminescence properties existed in the luminescent YPO4·0.8H2O nanocrystals. More interestingly, the YPO4·0.8H2O:Tb3+, Eu3+ samples could be effectively excited with 380 nm and the luminescence colors of YPO4·0.8H2O:Tb3+, Eu3+ nanocrystals can be easily tuned by changing the concentration of Eu3+ ions due to an efficient energy transfer from Tb3+ to Eu3+. These results revealed that the combination of the defect luminescence and rare earth-doping emission in YPO4·0.8H2O:Tb3+, Eu3+ nanocrystals could result in tunable emission in a large color gamut, which may be potentially applied in fields such as solid state lighting and field emission displays.

A method to calculate the weight of grating mosaic errors is proposed based on an analytical hierarchy process. An accurate mosaic error tolerance calculation formula is also presented that is useful for large-size grating fabrication by the mosaic method. The grating mosaic error weights and tolerances are analyzed for mosaic echelle gratings. The analytical error weight and tolerance results agree well with the experimental results. The mosaic grating's far-field intensity is 95.8%, which is higher than the 94% value from the simulation results.

Spatial heterodyne Raman spectrometry (SHRS) is a spectral analysis technique used to study material structures and compositions. We propose a multi-grating SHRS system that uses a multi-grating module rather than the single grating used to terminate each arm in traditional spatial heterodyne spectrometry (SHS). The proposed system not only retains the advantages of traditional SHS but also resolves the mutual limitation between system spectral range and resolution. The increased spectral range and resolution that can be achieved in detection are dependent on the number of sub-gratings used in the module. A verification system was built using 130 gr/mm and 150 gr/mm sub-gratings and calibrated. Under different experimental conditions (including laser power, integration time, container material and thickness, pure and mixed samples, and standoff experiments), the backscattered Raman spectra of different types of targets (including organic solutions, inorganic powders, and minerals) were tested. The multi-grating SHRS shows good performance for broad spectral range and high-resolution Raman detection.

A new broadband Raman spectrometer has been developed, to the best of our knowledge, using a double-echelle spatial heterodyne Raman spectrometer (DESHRS). The instrument is constructed by using two echelle gratings. Masks are used to remove the shadow ghosts caused by the different orders of the two echelle gratings. Raman spectra of inorganic solid targets and methanol are given, and Raman shifts of up to 3000 cm−1 are obtained by the DESHRS. The instrument has shown that a broadband coverage and high resolution can be achieved simultaneously to meet the requirements of Raman measurements, covering 3590 cm−1 with 1.21 cm−1 spectral resolution.

Objectives The aim of this study was to determine the effect of closing and opening muscle groups of the jaw on mandibular stability after prominent mandibular angle osteotomy, through three-dimensional finite element analysis (FEA). Materials and methods Six patients with prominent mandibular angles, without malocclusion, were selected as finite element models of preoperative and postoperative prominent mandibular angle surgery. Computed tomographic (CT) scans were undertaken of the patients before and after surgery and three-dimensional images reconstructed using Simpleware software. The images were imported into an FEA software. Boundary-constrained and load conditions were applied. The solution process was run, and actions of closing and opening muscle groups were simulated and calculated. Results The Von Mises stresses on the condyle position after the operation were higher than those before the operation. A significant difference was found between the stress distributions in the condyle position between prominent mandibular angle patients and mandibular angle ostectomy patients ( P Conclusions After osteotomy, the variation in force exerted by the closing and opening muscle groups of the jaw is one of the major factors affecting mandibular stability. FEA is a promising strategy in pre-surgical planning for improving surgical success and reducing complications.

In this study, we employed the metal-enhanced fluorescence (MEF) method for the detection of polycyclic aromatic hydrocarbons (PAHs) in diesel oil emulsions in artificial seawater. Silver nanoparticles with an average diameter of 80 nm were immobilized onto silanized quartz as MEF substrates. Excited by illumination at 355 nm, a 4.6-fold increase in the fluorescence signals of PAHs was recorded when MEF substrates were used. The finite-difference time-domain (FDTD) method was used to provide mechanistic insights into the fluorescence enhancement. Monitoring water pollution has environmental significance and MEF spectroscopy is finding direct applications in this field.

Gratings with stray light of 4.99 × 10−7-5.67 × 10−7 and efficiency of 93%-95% in a wavelength range of 1592 nm-1632 nm on Si-surface-modification SiC, fused silica and BK7 have been fabricated by the method of ICP etching-polishing. The CHF3 and SF6 plasma were used to etch a preliminary grating profile. Ar and O2 plasma with low energy were then used to polish the grating to acquire low surface roughness and groove profiles closer to the ideal profiles. The morphologies of the gratings were characterized by AFM. The efficiencies and stray light were measured quantitatively by self-developed equipment. These results show that the ICP etching-polishing method is a promising candidate for production of good quality gratings into common optical materials.