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The sufficient interface contact in the composite absorbing material is beneficial to increase the dielectric loss and promote the microwave absorption performance. In this paper, the composite nanoparticles (NPs), Fe3O4 covered with ultra-thin carbon layer (Fe3O4/C), were synthesized by simple high temperature solution-phase and subsequent high-temperature steam carbonization methods. Small size Fe3O4/C composite NPs have large heterogeneous interfaces, which can control the polarization loss of composite NPs through the method of interface regulation and achieve high microwave absorption performance. The strongest reflection loss of the composite NPs with an average particle size of 52 nm can reach −58.5 dB at 14.88 GHz with a thickness of 2 mm, and the corresponding effective absorption (RL ≤ -10 dB) bandwidth (EAB) is 5.63 GHz (12.37–18 GHz). In particular, the high-efficiency absorption (RL ≤ -20 dB) bandwidth of Fe3O4/C can reach 15.44 GHz (2–17.44 GHz) with a thickness of 1.7–10 mm. The current method for controlling polarization loss provide a meaningful reference for future microwave absorption research.

The synergistic effect of magnetic and dielectric materials makes this kind of composite as an ideal microwave absorber. So far, composite absorbing materials of Fe3O4 and carbon have been extensively studied and achieved excellent absorption properties. However, this type of absorber always has the problem of narrow effective absorption band (RL ≤ −10 dB). In this article, we have prepared 3D (Fe3O4/ZnO)@C double-core@shell nanocomposites by a clever method. Especially, the electromagnetic parameters and microwave absorption performances of the nanocomposites can be tuned by changing the zinc content. When the molar ratio of Zn to Fe is 1:2, the effective absorption bandwidth of the double-core@shell nanocomposite is 6.4 GHz with 2 mm thickness and 7.11 GHz with 1.9 mm thickness. Besides, when Zn:Fe = 1:1, the double-core@shell nanocomposite achieves a minimum RL value of −40 dB at 15.31 GHz with 2 mm thickness and has a wideband effective absorption of 6.5 GHz and an efficient absorption bandwidth (RL ≤ −20 dB) of 3.4 GHz. The special 3D double-core@shell structure and ingenious introduction of tunable ZnO could improve the microwave absorption performances of the (Fe3O4/ZnO)@C nanocomposites, which can be considered as promising absorbing materials.

To study the effect of surfactant synergistic composite acidification on the chemical structure and wetting characteristics of coal, in this paper, the influence mechanism of the chemical structure on the wetting characteristics of coal was studied. The results showed that the surfactant Sodium Dodecyl Sulfate (SDS) intensified the substitution reaction of the benzene ring structure of coal by composite acidification. The stability order of the radicals during acidification is –CH3 > –CH2 > –CH. In terms of the wetting characteristics of coal, ash and fixed carbon have a greater influence on the coal contact angle than the moisture and volatile component. The aromatic and aliphatic groups are hydrophobic structures, and the OH…OH interaction has the greatest influence on the wettability and belongs to the hydrophilic group. The research results have important guiding significance for coal seams to reduce coal dust pollution and deep impact ground pressure by applying surfactants to achieve synergistic composite acidification.

Background We aimed to assess the recurrence risk of sinonasal inverted papillomas (SNIPs), based on a staging system developed according to the originating site of SNIP. Methods A total of 200 patients with SNIP were enrolled, and a staging system was developed based on the originating sites and corresponding recurrence rates of tumor in the patients. In the verification phase, 675 patients with SNIPs were enrolled as above, and the originating sites of the SNIPs were confirmed by an endoscopic sinus surgery. Cluster analysis was performed to determine the stage for each SNIP. Results Overall, 608 patients completed the study. SNIP recurrence rates for stages 1‐4 were 0 (n = 43), 4.0% (n = 420), 13.4% (n = 134), 36.4% (n = 11), respectively (total = 6.4%). Conclusions The origin site‐based classification of SNIP may aid surgeons in selecting appropriate endoscopic surgical approaches to minimize the risk of recurrence.

Background: Serum periostin levels have been reported to be an indicator of Th2 inflammation in asthmatic patients. Objective: This study aimed to investigate serum levels of periostin in patients with allergic bronchopulmonary aspergillosis (ABPA) and to evaluate its diagnostic and monitoring value in the disease. Methods: Patients with ABPA (n = 19) and asthma (n = 24), including severe asthma with fungal sensitisation (SAFS, n = 11) and severe asthma without fungal sensitization (SAwFS, n = 13), were enrolled. Serum levels of periostin were analysed by enzyme-linked immunosorbent assay. Serum total IgE and Aspergillus fumigatus specific IgE, IgG were measured by ImmunoCAP. Levels of cytokines (IFN-γ, IL-4, IL-5, IL-8, IL-10, IL-13 and IL-17A) were measured by Meso Scale Discovery (MSD). Results: Serum levels of periostin in ABPA patients (85.55 ng/mL, [68.28-166] ng/mL) were higher than those in SAFS (50.99 ng/mL, [32.02-71.80] ng/mL; P

Vertical cavity surface emitting lasers (VCSELs) have lots of excellent properties, such as circular beam, low threshold, single longitudinal mode, high speed modulation and monolithic array fabrication capability. The VCSELs have been widely used in data communication and short-distance optical interconnection. In the fields of distance detection and automatic driving, high accuracy lidars have become an indispensable component. In practical applications, 905 nm laser exhibits little absorption by the water vapor in the air. In addition, the 905 nm laser can match with both inexpensive Si detector and high response avalanche photodiode (APD). Therefore, the 905 nm semiconductor laser has become a key light source of lidar. This paper presents the design and fabrication of 905 nm VCSEL with high power conversion efficiency. First, the main factors influencing the power conversion efficiency (PCE) of VCSEL are analyzed theoretically. It is concluded that the slope efficiency contributes to the PCE most. In order to achieve a high slope efficiency, strained InGaAs is used as a quantum well material. Due to the wavelength redshift caused by the thermal effect, the lasing peak wavelength of the multiple quantum well (MQW) is designed to be about 892 nm by optimizing the In composition. The active region consists of three pairs of In0.123Ga0.88As/Al0.3Ga0.7 MQWs. The N-distributed Bragg reflectors (DBRs) are designed to have 40 pairs of Al0.9Ga0.1As/Al0.12Ga0.88As, and the P-DBRs are designed to have 20 pairs of Al0.9Ga0.1As/Al0.12Ga0.88As. The epitaxial structure is designed and grown by metal organic chemical vapor deposition (MOCVD). The cavity mode of the epitaxial wafer is around 903.7 nm. The photoluminescence (PL) spectrum is also measured. The peak wavelength is approximately 893.7 nm, and the full width at half maximum is 21.6 nm. Then, the 905 nm VCSELs with different apertures (6–18 μm) are fabricated via semiconductor technologies such as photolithography, evaporation, inductively coupled plasma (ICP), wet oxidation, electroplating, etc. Finally, the L-I-V characteristics and spectra of VCSELs with different apertures are tested. The obtained maximum slope efficiency and PCE of the devices are 1.12 W/A and 44.8%, respectively. In addition, the influences of aperture size on the far-field profiles and spectra of the devices are investigated. These 905 nm VCSELs with high PCE are potential for the miniaturization and lowing the cost of LiDAR.

In order to enhance the wetting performance of surfactants to coal dust and reduce the harm caused by coal dust, different concentration of NaCl solution was added to the anionic surfactant of Sodium Dodecyl Sulfate (SDS). The effect of NaCl-SDS compound solution on wetting coal was studied by DSA25 optical droplet morphology analysis system and Fourier transform infrared spectroscopy (FTIR). The results show that the surface tension and contact angle decrease significantly with the increase of NaCl concentration in SDS. When the concentration of NaCl is 0.9 mol/L, the surface tension and contact angle are the lowest, which are 29.41 mN/m and 29.3°, respectively. In addition, adding NaCl to SDS can change the content of functional groups in coal, in which the content of methyl ( CH3) increases with the increase of NaCl concentration. The effect of CH3 content on the contact angle is the most significant, and the contact angle decreases with the increase of CH3 content. The addition of NaCl into SDS can effectively reduce the surface tension of the solution, reduce the contact angle between the solution and the coal sample, and improve the wetting effect. In this paper, a new compound solution is prepared by combining a surfactant and an inorganic salt, and the NaCl-SDS compound solution can further improve the wettability of the surfactant, and is of great significance in reducing the coal dust in the mining process of the coal mine.

Mechanical ventilation can induce lung fibrosis. This study aimed to investigate whether ventilator-induced lung fibrosis was associated with endothelial-mesenchymal transition and to uncover the underlying mechanisms.Randomized, controlled animal study and cell culture study.University research laboratory.Adult male Institute of Cancer Research, NACHT, LRR, and PYD domains-containing protein 3 (NLRP3) knockout and wild-type mice. Primary cultured mouse lung vascular endothelial cells.Institute of Cancer Research, NLRP3 knockout and wild-type mice were subjected to mechanical ventilation (20 mL/kg) for 2 hours. Mouse lung vascular endothelial cells were subjected to cyclic stretch for 24 hours.Mice subjected to mechanical ventilation exhibited increases in collagen deposition, hydroxyproline and type I collagen contents, and transforming growth factor-β1 in lung tissues. Ventilation-induced lung fibrosis was associated with increased expression of mesenchymal markers (α smooth muscle actin and vimentin), as well as decreased expression of endothelial markers (vascular endothelial-cadherin and CD31). Double immunofluorescence staining showed the colocalization of CD31/α smooth muscle actin, CD31/vimentin, and CD31/fibroblast-specific protein-1 in lung tissues, indicating endothelial-mesenchymal transition formation. Mechanical ventilation also induced NLRP3 inflammasome activation in lung tissues. In vitro direct mechanical stretch of primary mouse lung vascular endothelial cells resulted in similar NLRP3 activation and endothelial-mesenchymal transition formation, which were prevented by NLRP3 knockdown. Furthermore, mechanical stretch-induced endothelial-mesenchymal transition and pulmonary fibrosis were ameliorated in NLRP3-deficient mice as compared to wild-type littermates.Mechanical stretch may promote endothelial-mesenchymal transition and pulmonary fibrosis through a NLRP3-dependent pathway. The inhibition of endothelial-mesenchymal transition by NLRP3 inactivation may be a viable therapeutic strategy against pulmonary fibrosis associated with mechanical ventilation.

With the demand on integrated construction of large scale LNG facilities in non-slide way zone at marine construction site, finite element analysis with parametric modeling technology (ANSYS-APDL) are conducted to simulate nonlinear relationship of basement and the state of foundation settlement at the construction stage. Structural analysis models are simplified from 3D architecture models of build order in building information modeling (BIM) system through MATLAB interface development. Unfavorable settlement effects are examined by detailed analysis cases studying. The prediction results can guide installation and temporary reinforcement measures of large scale structures.

With the rapid development of marine exploration, the scale of offshore structures is getting large. It makes the slipways of marine construction site under critical bearing capacity and results in high-risk. Accurate evaluation of load responses of slipways can ensure the safety during construction and launching process and make use of them efficiently. Focusing on the issue, APDL technique is used in this paper to assessing mechanical performance of slab of the heavy slipway with maximum building capacity currently. Unfavorable live load distribution and contact conditions of panels are demonstrated under various serving conditions.

The paper presents an assessment methodology for comparable evaluation of a Spar and a Barge support with multi-megawatt OWT. Stability and hydrodynamic performance of both two floaters are checked by SESAM software. Taking consideration of rotational excitation frequencies of the OWT and primary wave excitations, reasonable engineering attributes of the structures are derived. The attributes are applied in multi-criteria decision making method-TOPSIS combining with environmental and economic attributes for benchmarking relatively better solution. The outcome of the study would contribute towards a more informed decision making process for the most suitable configuration of a new floating support structure for large wind turbine at deeper water.

Background Inflammation has been shown to be an integral component of allergic rhinitis (AR). However, there is no n worth debate regarding this fact in nonallergic rhinitis (NAR). Some studies have suggested that exclusion of inflammation is indicative of NAR and other studies have indicated that most of the NAR patients have some degree of inflammation. Recently, it has been shown that the level of immunoglobulin free light chains (IgFLCs) in serum is increased in some autoimmune diseases and airway inflammation. This study was designed to show whether IgFLC is associated with non–IgE-mediated rhinitis to reveal the relationship between the expression of IgFLC and activation of mast cells and eosinophils. Methods Thirty patients with IgE-mediated AR and 30 patients with NAR and 30 healthy persons as control were involved this study. The total IgE, IgFLC, eosinophil cationic protein (ECP) and mast cell tryptase (MCT) in serum, and nasal secretions were assayed, respectively. For identifying the expression cells of IgFLC in nasal mucosa, the immunohistochemical (IHC) staining for kappa-FLC, gamma-FLC, ECP, and MCT were performed on 30 specimens. Meanwhile, the mRNA expression of kappa-FLC, gamma-FLC, and MCT was determined by real-time quantitative polymerase chain reaction. Results IgFLCs (kappa/lambda) levels in serum and nasal secretion were significantly increased in AR patients and NAR patients. The ECP and MCT levels in serum and nasal secretion were significantly enhanced in AR and NAR patients when compared with healthy control subjects (p < 0.01). There was a positive correlation between IgFLC (kappa/lambda) and MCT n nasal secretion of patients with NAR, but only IgFLC (kappa-FLC was associated with MCT in AR. There was no correlation between IgFLC and ECP in nasal secretion. In serum expression level, there was a positive correlation between IgFLC (kappa) and ECP in AR or IgFLCs (lambda) and ECP in NAR. IHC staining showed that FLC+ cells were significantly increased in AR and NAR mucosa, kappa-FLC was mainly expressed in epithelial cells, and lambda-FLC was mainly expressed in subepithelial cells. Double immunofluorescence staining showed that the expression of lambda-FLC was mainly localized in mast cells in NAR nasal mucosa (45%). Conclusion These findings suggest strongly that IgFLC may play an important role in inducing local nasal mucosa inflammation especially those in AR and NAR.

BACKGROUND: Type 2 innate lymphoid cells (ILC2s) were shown to be involved in Th2-type immune responses in allergic disease animal models. ILC2s enrichment was shown in nasal polyps in chronic rhinosinusitis (CRS) patients and peripheral blood from asthma animal models; the role of ILC2s9 contribution of Th2 response in CRS and asthma remains to be investigated. AIMS: We hypothesized that there would be enhanced expression of ILC2s in peripheral blood of patients with CRS and asthma, which may show correlation with clinical features. METHODS: 6 CRS patients ,5 Asthma patients 5 healthy controls were recruited in our out-patient allergy clinic , ILC2 were quantized as Lin-CRTH2+CD127+ from PBMSs of subjects by using flowcytometry. SNOT-20 , VAS score and levels of IgE were also documented.IL-5 and IL-10 were measured in serum samples from patients by ELISA RESULTS: There were higher IC2 ratio (number of IC2s / one million PBMC %) in CRS group(0.958 ± 0.6209) and Asthma group(1.1191 ± 0.2611) , ,compared to healthy control(0.4831 ±0.0564).(p CONCLUSIONS: Our results showed the IL2s ratio were correlated with clinical features of allergic airway patients, type 2 innate immune responses were higher in CRS and asthma,ILC2 maybe a good marker of airway eosinophilic inflammation and peripheral blood is useful for evaluating type 2 innate immunity in human.

Large aperture proton-implanted vertical-cavity surface-emitting lasers (VCSELs) were fabricated. the uniformity of injection current was improved because of employing graphene as transparent conductive layer.

Indium tin oxide (ITO) transparent conductive layer was employed in oxide-confined vertical cavity surface emitting lasers. It can significantly improved the performance of VCSELs, such as output power and far field divergence angle.

Polarization stable characteristic of vertical cavity surface emitting laser array with rectangular element structure based on proton implantation is achieved. Arrays with different aperture sizes and different array scales are investigated. The maximum orthogonal polarization suppression ratio of a 6 × 6 array with 6 μm; × 4 μm elements is as high as 16.1 dB at 51 mA. The x-polarization dominates y-polarization in the operation current range from the threshold to the saturated current. The full widths at half maximum in far-field profiles for x-polarization and y-polarization are 8.8° and 10.7°, respectively. These results suggest that stable polarization is available in the implant-defined VCSEL array.

A three-dimensional electrical-thermal coupling model based on the finite element method is applied to study thermal properties of implant-defined vertical cavity surface emitting laser (VCSEL) arrays. Several parameters including inter-element spacing, scales, injected current density and substrate temperature are considered. The actual temperatures obtained through experiment are in excellent agreement with the calculated results, which proves the accuracy of the model. Due to the serious thermal problem, it is essential to design arrays of low self-heating. The analysis can provide a foundation for designing VCSEL arrays in the future.