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This study develops two different approaches to perform temporal and spatial measurements of surface wave profile for experimental studies in transparent wave flumes. Both are based on image acquisition and processing with an Internet of Things (IoT) system consisting of three sets of GoPro camera cum Raspberry Pi connected wirelessly together in a local LAN. The first approach uses advanced edge algorithms with perspective transformation of the multiple cameras for the detection, while the second approach adopts Convolutional Neural Network (CNN) algorithms instead with training of the processed image data using information from additional discrete probes installed. Their accuracy is assessed under a range of experimental conditions of regular and irregular waves with different wave heights and periods, based on metrics that consist of the average errors of the predicted water surface profile as well as position errors for wave crests and troughs. The effects on the measurement accuracy due to the image acquisition frequency, camera resolution and camera location are also investigated. The results show that higher wave steepnesses generally lead to larger detection errors, and measurements for irregular waves are also more challenging. In addition, positioning the cameras closer to the wave flume sidewalls yields better detection results as expected, particularly in resolving wave crests and troughs, although the field of view narrows at the same time. However, higher video frequencies and camera resolutions might not necessarily improve the accuracy contrary to common expectation due to jaggedness in the image processing. Overall, both approaches are shown to be viable for the measurement of wave profile in the laboratory. The first approach is more straight forward in terms of implementation, and it performs well for regular wave conditions. The second approach requires more complex training of the neural networks, but its accuracy is significantly higher particularly for irregular waves. [ABSTRACT FROM AUTHOR]

Sorbent morphology is significant to Hg0 removal performance due to its serious impacts on the number and availability of adsorption sites and the mass transfer of the Hg0 removal process. Given this, a novel sorbent was obtained by in-situ growth of Co 3 O 4 nanoparticles on channel walls of wood vessel which has regular mesoporous channels. The effects of synthetic conditions of hydrothermal temperature and NH 4 F concentration on sorbent morphology and Hg0 removal performance are investigated. Characterization results show that Co 3 O 4 nanoparticles integrate a monolithic shell as synthesis temperature rises, while the nanoparticles grow radially with the increase of NH 4 F concentration. Radial growth of nanoparticles results in a higher crystallinity. The sorbent synthesized at hydrothermal temperature of 90 °C with the NH 4 F concentration of 0.05 M (denoted as T 90 C 0.05) has uniform Co 3 O 4 nanoparticle size, homogeneous dispersion and a larger specific surface area. Furthermore, T 90 C 0.05 has a higher chemisorbed oxygen concentration and a higher Co3+/Co2+, which is of benefit to Hg0 removal process. Therefore, T 90 C 0.05 has an excellent Hg0 removal efficiency of 97% with a high gas hourly space velocity of 180, 000 h−1 at 200 °C and the Co 3 O 4 loading is only wt.5%. The effects of compounded flue gas components on the Hg0 removal performance were also studied. NO can weaken the inhibition effect of NH 3 through the reaction between NO and NH 3 forming labile [NH 2 NO]. In contrast, SO 2 can not weaken the inhibition effect of NH 3 due to the production coming from the reaction of SO 2 and NH 3 is stable at Hg0 removal temperature. [Display omitted] • A novel sorbent was obtained by in-situ growth of Co 3 O 4 on wood vessel channel. • The sorbent has ordered pore structure and uniform size of Co 3 O 4 nanoparticles. • The Hg0 removal efficiency is 97% at 200 °C with Co 3 O 4 loading amount of 5%. • The mechanism of the different effects of NO and SO 2 on Hg0 removal was studied. [ABSTRACT FROM AUTHOR]

Abstract: Deuterium quadrupolar echo NMR was applied to precision CD3 branched polyethylene at temperatures ranging from below the glass transition up to the melting point. The CD3 branches were placed on every 15th or 21st carbon with zero variation in the branch spacing by acyclic diene metathesis polymerization chemistry. The deuterium lineshapes were simulated and fit to the experimental spectrum assuming appropriate models that approximate the motions in the amorphous and crystalline phases. Spectral contributions of each phase were isolated by T 1 fitting. The fitting results comprise the isotropic reorientation correlation time distribution and axial jump angle distribution in these two phases, respectively. The mean jump angle was found to increase monotonically with temperature, approaching 35° near the melting point, consistent with previous carbon-13 NMR results on this same polymer. [Copyright &y& Elsevier]

Long non-coding RNA (lncRNA) potentially regulates tumorigenesis. LncRNA small nucleolar RNA host gene 1 (SNHG1) expression remains high in hepatocellular carcinoma cells; however, its biological mechanism in hepatocellular carcinoma remains unknown. In this study, SNHG1 expression in hepatocellular carcinoma cells was detected by qRT-PCR. Proliferative and migratory potentials of hepatocellular carcinoma cells were determined by CCK-8 and Transwell assay, respectively. Then, the nude mice model of xenograft was employed to verify the effect of SNHG1 on tumor formation in vivo. We identified the potential target of SNHG1 through bioinformatics and dual-luciferase reporter gene. Furthermore, Western blot and RIP assay was used for clarifying their interaction and functions in regulating the development of hepatocellular carcinoma. Our results indicated a high expression of SNHG1 in hepatocellular carcinoma cells. Downregulation of SNHG1 inhibited proliferative and migratory potentials of hepatocellular carcinoma cells in vitro and in vivo. Moreover, the expression of programmed cell death 4 (PDCD4) was positively regulated by SNHG1 through competing with miR-195-5p. These results indicated that SNHG1 participated in the development of hepatocellular carcinoma as a ceRNA to competitively bind to miR-195-5p and thus mediate PDCD4 expression. • Our results indicated a high expression of SNHG1 in HCC cells. • SNHG1 promotes cell proliferation and migration in vitro and in vivo. • SNHG1 acts as a ceRNA to promote HCC progression by sponging miR-195-5p. [ABSTRACT FROM AUTHOR]

[Display omitted] • Co 3 O 4 nanosheets with different amount of oxygen vacancies were synthesized. • Higher reduction level can over reduce Co 3 O 4 leading to lower oxygen vacancies. • The over reduced Co 3 O 4 will adsorb O 2 forming lattice oxygen not chemisorbed one. • Suitable reduction condition give more oxygen vacancies and improve Hg0 removal. Oxygen vacancy is very important for the Hg0 oxidation process due to it can capture and activate gaseous oxygen forming surface chemisorbed oxygen to oxidize Hg0 to HgO. Precise control of oxygen vacancies amount is a big challenge in this field. For Co 3 O 4 , oxygen vacancy can be generated by Co3+ reduction to Co2+ and Co3+ mainly exist in (2 2 0) facet. Thus, in the present work, Co 3 O 4 nanosheets preferentially growing (2 2 0) facet with more Co3+ were synthesized and CO was used as reduction agent to reduce Co 3 O 4 at different reduction condition. After that, Co 3 O 4 nanosheets with different amount of oxygen vacancies were obtained. XPS, Raman and PL results show that, the amount of oxygen vacancies increase firstly and then decrease with the increase of reduction temperature and time. CO can reduce Co3+ to Co2+ forming oxygen vacancies. However, when the reduction temperature and time are at a high level, Co 3 O 4 will be over reduced to CoO leading to a decrease of oxygen vacancies. DFT confirm that, when Co 3 O 4 is over reduced, O 2 will hard to adsorb on Co 3 O 4 surface and lattice oxygen will be formed even after O 2 adsorption. Co 3 O 4 -Te 300 Ti 2 has an optimal reduction degree leading to higher oxygen vacancy concentration and better O 2 adsorption and activation ability. Therefore, Co 3 O 4 -Te 300 Ti 2 has a high Hg0 oxidation efficiency which is over 96 % in a wide temperature range of 150–300 °C at a high GHSV of 180,000 h−1. [ABSTRACT FROM AUTHOR]

[Display omitted] • Co 3 O 4 nanosheet was successfully grown in the interlayer space of g-C 3 N 4. • Electron will transfer from g-C 3 N 4 to Co 3 O 4 improving oxygen activation. • The Hg0 removal efficiency of 20%Co 3 O 4 /NS-g-C 3 N 4 was about 97% at 250 °C. • Hg species on sorbent surface and the adsorption mechanism were investigated. Hg0 adsorption with sorbents is a widely used way to remove Hg0 from coal fire flue gas. The adsorption efficiency and capacity are limited by the activation and number of the surface adsorption sites. In the present work, a series of composite sorbents with nanosheet structure were successfully synthesized by in situ growth of Co 3 O 4 nanosheets in the interlayer space of g-C 3 N 4. The effects of the mass ratio of Co 3 O 4 /g-C 3 N 4 on sorbent physicochemical properties were comprehensively studied. Characterization results show that, when the mass ratio of Co 3 O 4 /g-C 3 N 4 is 20%, the corresponding sorbent of 20%Co 3 O 4 /NS-g-C 3 N 4 has well dispersion of Co 3 O 4 nanosheets in g-C 3 N 4 interlayer (SEM and TEM) and a relatively large BET area (BET). It results in a larger amount of surface chemisorbed oxygen which can react with Hg0 forming HgO. Furthermore, the strong interaction between Co 3 O 4 and g-C 3 N 4 make electron transfer from g-C 3 N 4 to Co 3 O 4 improving oxygen activation. Therefore, 20%Co 3 O 4 /NS-g-C 3 N 4 has a higher Hg0 removal efficiency of 97% at 250 °C and it maintains above 80% even after 70 h test. XPS, FTIR and Hg0 desorption experiment results confirm that the adsorbed Hg mainly stays in the form of HgO and a probable adsorption mechanism is deduced by these results. [ABSTRACT FROM AUTHOR]

[Display omitted] • GO support sigle-atom Co catalysts were successfully synthesized. • MOF on GO has highly dispersion degree giving a large BET surface area. • The Co in MOF mainly stay in single-atom status which is the main active site. • The Hg0 oxidation activity of Co 2.5 -SAs@NC/GO-1 is above 95 % at 120–180 °C. Oxidation of Hg0 to Hg2+ is an efficient way to remove Hg0 from flue gas. Chemisorbed oxygen as the main active site plays an important role in Hg0 oxidation process. Single-atom catalyst has an excellent ability of transforming gaseous oxygen into chemisorbed oxygen. In the present work, graphene oxide (GO) was used as support to in-situ grow Co/Zn bimetallic MOF on GO surface. After pyrolysis, a GO supported Co@C single-atom catalyst was obtained. SEM and TEM results show that GO supporting gives a high dispersion for calcined MOF particles. HAADF-STEM results prove that most of the Co atoms in calcined MOF particles stay as single-atom status. EXAFS indicated that the Co atoms in the catalyst was coordinated with N, and the coordination was dominated by CoN 2. CoN 2 can capture and activate gaseous oxygen forming more chemisorbed oxygen. Thanks to the high dispersion of calcined MOF and higher chemisorbed oxygen concentration, the Hg0 oxidation efficiency of the obtained catalyst (Co 2.5 -SAs@NC/GO-1) can reach above 90 % in the temperature range of 120–180 °C with 0.075 g loading amount at the GHSV of 180, 000 h−1. The probable reaction pathway was analyzed by an adsorption–desorption experiment and XPS over the used and regenerated Co 2.5 -SAs@NC/GO-1. [ABSTRACT FROM AUTHOR]

None-felt needling technology is a novel 3D preform preparation technology, which improved the mechanical properties of needled preforms effectively. However, the mode I interlaminar fracture behavior of none-felt needled composite has not yet been clarified. In this paper, none-felt needled fabrics and their composites were prepared, the structure of the fabrics was characterized, and mode I interlaminar fracture performance of the composites were carried out through experiments and simulation method. It was found that none-felt needled composites showed effect on improving mode I interlaminar fracture property compared with the traditional needled composites, the maximum failure load and interlaminar fracture toughness (G IC) increased by up to 107% and 129% respectively. The double cantilever beam (DCB) experiment revealed that the failure mode of the none-felt needled composites were manifested as cracking of the matrix and brittle fracture of the needled fiber bundles. More content and thicker needled fiber bundles of none-felt needled fabric are important factors to improve the mode I interlaminar performance. Moreover, based on the failure mechanism and the structural features, mode I simulation model of none-felt needled composites was developed. The load–displacement curves obtained from the simulations were well closed to the experiment, and the error range was between 2.0% and 7.5%. None-felt needled composite structure with high interlaminar properties is hopeful to be applied in composite thin-walled components such as radomes and cabin sections of high-speed aircraft. [Display omitted] • The mode I interlaminar fracture behavior of none-felt needled composite was studied by experiment and simulation method. • None-felt needled composite showed great improvement in mode I interlaminar fracture property. • The maximum failure load and interlaminar fracture toughness (G IC) increased by up to 107% and 129% respectively. • The none-felt needled composite have more and thicker needled fiber bundles than the traditional needled composite. • The load-displacement curves obtained from the simulations were well closed to the experiment. [ABSTRACT FROM AUTHOR]

As a global mental disorder, depression is associated with oxidative stress in the brain. Cysteine, a reductive biothiols, regulates the oxidative situation in many biological events including the stress that occurs in the tissues. Exploring the pathology and physiology of depression is still a challenge and always in an urgent need. Thus, developing a new method that could track Cys level without the interferes from other competing substances is of great importance. Herein, we developed a fluorescence probe that could selectively sensing Cys over other biothiols. Besides, we have demonstrated its desirable performance in cellular applications and mouse brain. This work provides a new method for Cys imaging and understanding pathogenesis of depression. We hope the work described here could be used as a potential chemical approach for the diagnosis of Cys associated diseases in clinical applications. [Display omitted] [ABSTRACT FROM AUTHOR]

• The mode Ⅱ interlaminar shear strength of none-felt needled composites increased by up to 108.6%. • Double cohesive zone model was established to predict the mode Ⅱ interlaminar shear property. • The in-plane tensile strength and modulus improved by 19%–21% and 11%–20% respectively. • The interlaminar shear and in-plane tensile properties of the needle-punched composite were simultaneously improved. The none-felt needling technology improved the interlaminar peeling and in-plane tensile property of the needled fabric. Following the previous research, this paper proposed a study on the interlaminar shear property of the none-felt needled composites by using experiments and numerical methods, and compared with common felt/base cloth needled composites. Result showed that none-felt needled composites had great enhancement in interlaminar shear strength, increased by up to 108.6%. Double cohesive zone models were established to predict the mode Ⅱ interlaminar shear property of none-felt needled composites. The simulation of interlaminar shear strength and the surface strain cloud graph were well close to the experimental results. Moreover, tensile and bending properties were also characterized. The in-plane tensile strength and modulus increased by up to 21% and 20% respectively. The bending strength and modulus improved by 3%–7% and 4%–13%. The none-felt needling technology realized the simultaneous enhancement of interlaminar shear and in-plane tensile properties of needled composites, which may further broaden the application fields of needled composites. [ABSTRACT FROM AUTHOR]

Abstract: Botulinum neurotoxins (BoNTs) are the most poisonous substances ever known. The early detection of these toxins could bear more time for appropriate medical intervention. The standard method for detecting BoNTs is the mouse bioassay, which is time consuming (up to 4 days) and requires a large number of laboratory animals. The immunologic detection methods could detect the toxins within a day, but most of these methods are less sensitive compared with the mouse bioassay due to the lack of high-affinity antibodies. Recently, the recombinant HC subunit of botulinum neurotoxin type A (rAHC) was expressed as an effective vaccine against botulism, indicating that the rAHC could be an effective immunogen that raises the monoclonal antibody (mAb) for detecting BoNT/A. After immunized BALB/c mice with rAHC, 56 mAbs were generated. Two of these mAbs were selected to establish a highly sensitive sandwich chemiluminescence enzyme immunoassay (CLEIA), in which FMMU-BTA-49 and FMMU-BTA-22 were used as capture antibody and detection antibody, respectively. The calculated limit of detection (LOD) based on molecular weight of rAHC and BoNT/A reached 0.45pgmL−1. This CLEIA can be used in the detection of BoNT/A in matrices such as milk and beef extract. This method has 20–40 fold lower LOD than that of the mouse bioassay and takes only 3h to complete the detection, indicating that it can be used as a valuable method to detect and quantify BoNT/A. [Copyright &y& Elsevier]

• The novel none-felt needling technology was proposed. • Properties of needled fabrics were significantly improved by none-felt needling. • The study established the possibility of developing high density needled fabrics. An attempt has been made to explore the possibility of manufacturing high performance needled fabrics by none-felt needling technology. The concept of half-cut cloth and none-felt needling were proposed. Experiments were designed to study the influence of different half-cut cloth and different base cloth on the structure parameters of the none-felt needled fabrics, as well as the interlayer peeling and in-plane tensile properties. It was observed that the needled fabrics prepared by none-felt needling technology depicted considerable enhancement in volume density, interlayer peeling strength and in-plane tensile strength. The fabric structure, density and half-cut width of half-cut cloth, and the density of the base cloth presented a significant influence on the mechanical properties of none-felt needled fabrics. The study established the possibilities of developing new high density needled fabrics, which greatly improved interlayer and in-plane performance. The none-felt needled fabric is expected to be used for high-speed aircraft radome materials. [ABSTRACT FROM AUTHOR]