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Abstract: The B4C nanowires can be easily fabricated by employing an activated carbon, boron and Ni(NO3)2 whereas almost no B4C nanowires can be obtained if activated carbon is replaced by pure carbon. The analyses show that there are Si and Al impurities in the activated carbon, and both Si and Ni are critical to the growth of the B4C nanowires. Additionally, the yield of the B4C nanowires is greatly increased if the B4C nanowires are grown by the carbon nanotubes-confined method when Si is introduced. The mechanism of the Si enhanced growth of B4C nanowires is discussed. [Copyright &y& Elsevier]

A novel water-soluble ligand of N,N,N‴,N‴ -tetraethyl- N ′ ,N ″-ethidene bisdiglycolamide (TEE-BisDGA) was synthesized and used as a masking agent for selective extraction of Am(III) over Eu(III) from HNO 3 solution by N,N,N ′, N ′ ,N ″ ,N ″-hexaoctylnitrilotriacetamide (NTAamide(C8)) in kerosene. Influences of acidity, concentration of water-soluble ligands and extractant as well as nitrate ions on the distribution ratios ( D ) and separation factors ( SF ) of Am(III) and Eu(III) were investigated. In the range of examined acidity from 0.001 to 0.2 mol/L, D Am and D Eu decreased with the increase of HNO 3 concentration. Using 0.1 mol/L NTAamide(C8) as an extractant, the maximum SF Am/Eu of 26 can be obtained in the presence of 0.01 mol/L TEE-BisDGA in aqueous phase with pH of 3.0, which was significantly higher than that case with no TEE-BisDGA. Job's method and mole ratio method were employed for extraction mechanism research. It has been shown that Am(III) and Eu(III) formed di-solvated species with TEE-BisDGA and mono-solvated species with NTAamide(C8), respectively. Moreover, the stability constants logβ values were obtained from UV–vis adsorption spectroscopic titration for Nd(III) complexes with TEE-BisDGA and N,N,N ′ ,N ′-tetraethyldiglycolamide (TEDGA), which indicated that TEDGA had a stronger complex ability than TEE-BisDGA. [ABSTRACT FROM AUTHOR]

The two-stage suspension system (TSSS) is designed for the fiber optic vector hydrophone (FOVH) to isolate the vibration from the mooring rope. The acceleration transmissibility of the TSSS is studied theoretically and experimentally. The results show that the TSSS has a major advantage over the traditional one-stage suspension system (OSSS). Typically, the vibration isolation of the TSSS is demonstrated to be over 25 dB higher than that of the OSSS at 100 Hz. Meanwhile, it is demonstrated that the TSSS has little negative influence on the in-band acceleration response of the FOVH. The TSSS has the prospect of reducing the mechanical noise of the FOVH, which is conducive to suppressing the self-noise and enhancing the ability of weak signal detection. [ABSTRACT FROM AUTHOR]

Modulation instability (MI) is the main limitation factor of the maximum optical power in long-haul phase-sensitive optical time domain reflectometry (Φ-OTDR), and induces signal fading and serious phase noise. In this paper, a method of coherent seed injection is proposed to suppress the MI-induced phase noise in long-haul Φ-OTDR. The spontaneous MI is suppressed by stimulating induced MI in an optical fiber. The visibility of the signal in Φ-OTDR is enhanced and the phase noise is suppressed significantly. This paper offers an effective method to increase the maximum input power with the MI-induced phase noise suppressed in the long-haul Φ-OTDR system. As a result, the maximum input power and sensing distance can be potentially increased, which is greatly beneficial to the enhancement of the performance of long-haul Φ-OTDR. [ABSTRACT FROM AUTHOR]

Thermal effect inevitably occurred in a bipolar membrane electrodialysis (BMED) stack impacts its energy efficiency and potentially damages non-metallic components. Up to now, thermal mechanism and impacts within a BMED stack remain incompletely understood. Thus, thermal mechanism and impacts within the stack were investigated using the validated equivalent circuit model of a BMED system. Its results revealed that currents/Joule effect in the main circuit were dominant compared to those in the external circuit. The proportion of Joule heat in the main circuit exceeds 99.00 %, while that in the external circuit was less than 1.00 %. Joule heat generated in the outermost slot of the maximum conductivity compartment was obvious, while that in any position of the main circuit within the minimum conductivity compartment was also significant. Thermal impacts of non-metallic components were affected by the heat transfer of solution thermal effect. Besides, these effects which included current distribution, Joule effect, and thermal risk, were mainly affected by the size of the element at spacer, and the conductance provided by the salt and its products. Larger size of slots/ducts at spacer reduced the heat transfer efficiency at their location, while that of main channel enhanced the heat transfer efficiency between membranes and solution. Low conductivity salts and corresponding products pose a greater thermal risk for BMED stack. Meanwhile, these effects would be aggravated from the lab- to large-scale BMED stack. These findings can enhance the comprehension of the involved processes for optimizing BMED technique, thereby accelerating its development. [Display omitted] • Thermal mechanism in a BMED stack was caused by current distribution of main/external circuit. • Thermal risk of non-metallic components was affected by heat transfer of solution thermal effect. • Larger size of slots at spacer reduced the heat transfer efficiency at their location. • Low conductivity salts and corresponding products pose a greater thermal risk for BMED stack. [ABSTRACT FROM AUTHOR]

• Vehicle modal parameters are identified using the free responses from the field tests of a vehicle passing over humps. • The road roughness can be estimated accurately using the measured vehicle responses from the field tests. • The proposed method can be easily and effectively performed with a few accelerometers only. Accurate information about vehicle parameters and road roughness is of great significance in vehicle dynamic analysis, road driving quality, etc. In this study, a method for estimating vehicle parameters and road roughness was developed using the measured vehicle responses from field tests which is efficient, economical, and accurate. First, the full-vehicle model was introduced. Then, vehicle modal parameters were identified using the consequent free responses of a vehicle passing over bumps. Second, the expression of the vehicle frequency response function (FRF) with respect to the wheel contact point was derived from the vehicle equation of motion, and a road roughness estimation method based on the vehicle FRF was developed. Third, field tests in which the vehicle passes over bumps were performed for vehicle model identification. Finally, field tests for road roughness estimation were carried out using a calibrated vehicle to verify the effectiveness of the proposed methods. [ABSTRACT FROM AUTHOR]

The mammalian olfactory system uses a large family of odorant receptors (ORs) to detect and discriminate amongst a myriad of volatile odor molecules. Understanding odor coding requires comprehensive mapping between ORs and corresponding odors. We developed a means of high-throughput in vivo identification of OR repertoires responding to odorants using phosphorylated ribosome immunoprecipitation of mRNA from olfactory epithelium of odor-stimulated mice followed by RNA-Seq. This approach screened the endogenously expressed ORs against an odor in one set of experiments using awake and freely behaving mice. In combination with validations in a heterologous system, we identified sets of ORs for two odorants, acetophenone and 2,5-dihydro-2,4,5-trimethylthiazoline (TMT), encompassing 69 OR-odorant pairs. We also identified shared amino acid residues specific to the acetophenone or TMT receptors and developed models to predict receptor activation by acetophenone. Our results provide a method for understanding the combinatorial coding of odors in vivo. [ABSTRACT FROM AUTHOR]

Background: With a pronounced and historically unprecedented tendency of population ageing, research on ageing and related disorders has been increasingly brought into focus. Horticultural therapy (HT), as an important role of social prescribing, has been an integrative for decades. This systematic review and meta-analysis aimed to evaluate HT for general health in older adults. Methods: Electronic databases including PubMed, Web of Science, ScienceDirect, the Cochrane Library, MEDLINE (Ovid), EMBASE (Ovid), CINAHL (EBSCO), China National Knowledge Infrastructure (CNKI), and the Wanfang database, grey literature databases and clinical trials registers were searched from inception to March 2021. Randomized controlled trials (RCTs), quasi-RCTs (QRCTs) and the cohort studies about HT for adults aged over 60 were included in this study. Outcome measures were physical function, quality of life, BMI, mood tested by self-reported questionnaire and the expression of the immune cells. The study was registered under PROSPERO (CRD42019146184). Results: Totally, fifteen studies (thirteen RCTs and two cohort studies) involving 1046 older participants were included. Meta-analysis showed that HT resulted in better quality of life (MD 2.09, 95% CI [1.33, 2.85], P<0. 01) and physical function (SMD 0.82, 95% [0.36, 1.29], P<0.01) compared with no-gardener; the similar findings showed in BMI (SMD -0.30, 95% [-0.57, -0.04], P = 0.02) and mood tested by self-reported questionnaire (SMD 2.80, 95% CI [1.82, 3.79], P<0. 01). And HT might be conducive on blood pressure and immunity, while all the evidence were moderate-quality judged by GRADE. Conclusions: HT may improve physical function and quality of life in older adults, reduce BMI and enhance positive mood. A suitable duration of HT may be between 60 to 120 minutes per week lasting 1.5 to 12 months. However, it remains unclear as to what constitutes an optimal recommendation. [ABSTRACT FROM AUTHOR]

Abstract: A test method for spherical mirrors with super-long radius of curvature that only one compensator is employed to measure the radii of curvature of both concave and convex mirrors is presented. With this testing system, the surface figure and radius of curvature of spherical mirrors can be measured simultaneously. Using the ABCD matrix method, a precise formula for radius of curvature calculation is deduced. Experimental results show that the relative measurement error of this method is less than 4.2×10−4. [ABSTRACT FROM AUTHOR]

Purpose: This paper aims to focus on the preparation of Kevlar fiber (KF) and alkaline hydrolyzed KF (KF-H) to improve the dispersed condition of polyaniline (PAn), as the aggregation of PAn would lead to some adsorption sites buried. And then the materials were used to enrich anionic dye Congo red (CR) from aqueous solution. Design/methodology/approach: The materials (KF@PAn and KF-H@PAn) were designed by means of "diffusion-interfacial-polymerization" under mild condition as high affinity due to the structural properties of PAn, KF and KF-H. The dispersed degree of PAn on the surface of KF and KF-H was validated according to adsorption efficiency for CR. Findings: The content of PAn introduced was not beyond 20 wt.%, while adsorption capacity for CR was significantly enhanced by 4–8 times (on the basis of kinetic data) according to the calculation only by the content of PAn due to KF and alkaline hydrolyzed KF exhibited almost no adsorption for CR, indicating dispersed situation of PAn coating was greatly enhanced and more active sites exposed, which was favorable for the adsorption process. Presence of NaCl would exhibit a more or less positive effect on CR uptake, suggesting the materials could be used for high salt environment. Research limitations/implications: The investigated means of dispersed degree of PAn on the surface of KF and KF-H are the further and future investigation. Practical implications: This study will provide a method to improve the dispersed situation of PAn and a theoretical support to treat anionic dyes from aqueous solution especially for salt environment. Originality/value: The results showed that the dispersed condition of PAn on the surface of KF and KF-H was greatly improved. According to the adsorption capacities for CR, it can be concluded that part of adsorption sites were buried due to the aggregation of PAn, and introduction of KF and KF-H, buried adsorption sites decreased greatly. This study will provide a method to decrease buried adsorption sites of PAn and a contribution for their convenient application in wastewater treatment especially for high salt environment. [ABSTRACT FROM AUTHOR]

Carbocysteine (H 2 ccys) wastewater, which contains H 2 ccys, chloroacetic acid, and ammonium chloride, can pose significant risks to the environment. In this study, a novel strategy was proposed for treating H 2 ccys wastewater by bipolar membrane electrodialysis (BMED) to realize resource recovery. The migration and coexistence mechanism of organic/inorganic ions in wastewater were investigated in lab-scale experiments. The results indicated that the desirable migration of inorganic ions, such as NH 4 + and Cl− ions, in the feed compartment were dominant. The undesirable migration of organic molecules, such as ClCH 2 COOH and H 2 ccys, could be managed through precise control of the BMED reaction process. To optimize the energy efficiency and thermal effect occurred in the pilot-scale, a two-stage BMED process was designed for treating H 2 ccys wastewater. The results revealed that BMED produced 1.33–1.63 M of HCl and 2.62–2.88 M of NH 3 ·H 2 O, and removed 90 wt% of NH 4 Cl from H 2 ccys wastewater. Meanwhile, the thermal effect of the slot at the outermost acid compartment decreased from 3.32 W in the one-stage BMED process to 0.10 W in the two-stage BMED process during the pilot-scale tests. The current efficiency of the two-stage BMED process for the acid/base production and feed desalination in the pilot-scale tests increased and its energy consumption decreased compared with the lab-scale tests. Moreover, the BMED r r ecycling route showed that a closed loop can be realized in the treatment of H 2 ccys wastewater, and its economic assessment showed that applying BMED to the treatment of H 2 ccys wastewater have economic benefits. These findings illustrated the feasibility of this novel strategy for treating H 2 ccys wastewater and laid a solid foundation for its industrialization. [Display omitted] • H 2 ccys wastewater treated by BMED process was investigated from lab-to pilot-scale. • Migration and coexistence mechanism of the ions in H 2 ccys wastewater were identified. • Novel concept of the stack design that prioritizes thermal effects was initially applied. • In situ application route of BMED products was established on the basis of recycling concept. • Economy of utilizing BMED to treat H 2 ccys wastewater was assessed. [ABSTRACT FROM AUTHOR]

Selective serotonin reuptake inhibitors (SSRIs) are first-line antidepressants, however, only around 60% of patients could benefit from them. Acupuncture is supported by insufficient evidence to help with symptom relieving and SSRIs tolerance. This pragmatic randomized controlled trial compared SSRIs alone versus SSRIs together with manual acupuncture (MA) or electroacupuncture (EA) in moderate to severe depressed patients. Patients were randomly allocated to receive MA + SSRIs (161), EA + SSRIs (160), or SSRIs alone (156) for six weeks, and then followed up for another four weeks. The primary outcome was response rate of the 17-item Hamilton Depression Scale (HAMD-17) at 6th week. The secondary outcomes were HAMD-17 (remission rate, early onset rate, total score), Self-Rating Depression Scale (SDS: total score), Clinical Global Impression (CGI), Rating Scale for Side Effects (SERS: total and domain scores), number of patients with adjusted dosage of SSRIs and adverse events (AEs). Both MA + SSRIs and EA + SSRIs were significantly better than SSRIs at 6th week on HAMD-17 response rate (RR = 1.21, 95% CI 1.04, 1.42, P = 0.013; RR = 1.27, 95% CI 1.09, 1.48, P = 0.0014), HAMD-17 early onset rate (P < 0.0001), HAMD-17 and SDS total scores (P < 0.05), CGI (P < 0.01), SERS total score (P < 0.01), number of patients with increased dosage of SSRIs (P < 0.01). For HAMD-17 remission rate, EA + SSRIs was significantly higher than SSRIs (P = 0.0083), while MA + SSRIs showed no significant difference at 6th week (P = 0.092). No unintended acupuncture-related severe AE was observed. This study identified that both MA and EA showed beneficial effects in addition to SSRIs alone in patients with moderate to severe depression, and were well tolerated. Clinical trials registration: ChiCTR-TRC-08000297. [ABSTRACT FROM AUTHOR]

In this work, a unique Ppy@NiCo 2 S 4 core-shell heterostructure material is prepared taking polypyrrole (Ppy) nanotubes as skeleton through a simple and environmentally friendly hydrothermal method. The heterostructured structure with Ppy nanotubes (NTs) as the core and intertwined flake-like NiCo 2 S 4 as the outer shell, holds a large specific surface area (217 m 2 g −1 ), convenient charge transport channel, high specific capacitance (908.1 F g −1 at a current density of 1 A g −1 ), and excellent cycling performance (87.7% of initial value is retained after 2000 cycles). What’s more, an asymmetric supercapacitor is fabricated by employing Ppy@NiCo 2 S 4 core-shell heterostructured material as positive and nitrogen-doped carbon nanotubes (N-C NTs) as negative electrode. This Ppy@NiCo 2 S 4 //N-C asymmetric supercapacitor effectively provides a high energy density over 50.82 Wh kg −1 with a high power density of 160 W kg −1 and preeminent cyclic stability of 126.6% after 2000 cycles. Due to the introduction of one-dimensional flexible Ppy inner core, as-designed the core-shell heterostructure composite may be promising in the flexible energy storage devices. [ABSTRACT FROM AUTHOR]

This paper develops an approach that estimates the range and depth of a broadband source by adopting the vector hydrophone vertical array (VHVA) in the deep ocean. The sound field in the direct wave zone is mainly composed of direct (D) and once-sea-surface-reflected (S1B0) waves. The arrival angles and time delays of the two waves are consistent. The combined beamforming technology is applied to the VHVA to accurately obtain the elevation angles and further enhance the received signal-to-noise ratio (SNR). The source ranges are then estimated according to the simple geometric relationship. The source depth estimation model is established based on the Lloyd-mirror principle, which relates the interference properties of D and S1B0 to the oscillation period of the combined signals of VHVA. The feasibility and availability of this method are validated by both simulations and sea trials in the South China Sea. The experimental results indicate the range estimation error of the moving vessel is less than 10% and the surface or submerged targets can be effectively determined. Our proposed algorithm has the strong benefits of simple principle, low computational complexity and small error. These properties indicate this algorithm can be used in target detection in the deep sea. • Applying the combined beamforming to the vector hydrophone vertical array to estimate elevation angle more accurately. • Providing a simple method for range and depth estimation. • Range estimation error of a moving vessel is less than 10% in the direct zone. • Recognizing surface or submerged targets effectively at moderate ranges. • Valuable deep-sea data in the experiment. [ABSTRACT FROM AUTHOR]

Two diglycolamide homologs, N,N,N′,N′-tetraoctyl-3,6-dioxaoctane diamide (DOODA) and N,N,N′,N′-tetraoctyl-3,6,9-trioxaundecane diamide (TOUDA), were synthesized. Their extraction behaviors of Am and Eu were investigated and compared with those of N,N,N′,N′-tetraoctyl-3-oxapentane diamide (TODGA). The extraction ability toward Am and Eu decreased with increasing etheric oxygen number in the extractant structure. In contrast to TODGA, an very interesting inversion on the selectivity occurred for DOODA and TOUDA, which were more favor of extracting Am than Eu. The maximum SF of 3.5 for DOODA can be achieved at 3.0 mol/L HNO. The stoichiometries of extracted species and extraction thermodynamic parameters were also presented. Graphical Abstract: [ABSTRACT FROM AUTHOR]

Accurate vehicle parameter information plays an important role in assessing the conditions of roads and bridges, along with the corresponding maintenance. This study considered a vehicle parameter identification method based on a vehicle frequency response function (FRF). First, the vehicle FRF was deduced with respect to the displacements of the vehicle-road contact points, thereby building the relationships among the FRF, vehicle responses, and road profile in the frequency domain. Next, using the responses of vehicles passing over on-road bumps of known size, a direct estimation of the vehicle FRF was described. Then, a combination of Tikhonov regularization and a shape function method was used to update the estimated vehicle FRF by removing the singular data owing to the direct computation of the vehicle FRF. Subsequently, the modifying factors of the vehicle parameters were iteratively identified based on a sensitivity analysis of the estimated FRF to the vehicle parameters. A numerical simulation for vehicle parameter identification was performed to test the effectiveness of the proposed methods, considering a 5% Gaussian noise pollution and the influences of different driving speeds. At last, field tests of a vehicle passing over bumps were performed for the verification of vehicle parameter identification. [ABSTRACT FROM AUTHOR]

[Display omitted] • The polyethylene glycol brush grafted from nitrile butadiene rubber is successfully prepared and characterized with the reactive site found. • The brush improves the tribological performance of NBR, with coefficient of friction reduced by 73.4% at 100 rpm in particular. • The Fast Sample Entropy Diagram is proposed to analyze the friction-induced vibration visually. The water-lubricated bearing will be in a state of poor lubrication when marine stern shafts operate under low speed and heavy load conditions, which could cause severe wear and vibration, endangering the stealth performance of underwater vehicles. In this study, the grafting of polyethylene glycol brush was carried out on the surface of nitrile butadiene rubber (PEG-g-sNBR) by "grafting from" method. Fourier-transform-infrared-spectroscopy, nuclear-magnetic-resonance, and scanning-electron- microscope results demonstrated that the PEG-g-sNBR brush was successfully synthesized, and the reactive site was found. Using a tribological test machine with a high-precision vibration acceleration sensor, the tribological behaviors of PEG-g-sNBR were studied under aqueous lubrication. The results showed that the coefficient of friction of PEG-g-sNBR was reduced by 73.4% at 100 rpm compared to pure NBR, its microscopic wear and vibrational energy were also lower than pure NBR. Moreover, the lubrication states were revealed by friction, wear, together with the complexity of friction-induced vibration signal time series, and a lubricating film was formed on the friction surface of PEG-g-sNBR at lower rotational speed. In addition, the PEG-g-sNBR could work stably for 12 h at 300 rpm, and still maintain good tribological performance. [ABSTRACT FROM AUTHOR]

When marine stern shafts operate under low speed and heavy load conditions, the metal shaft and water-lubricated bearing will be in a state of boundary lubrication or even dry friction. Poor lubrication can cause severe wear and friction-induced vibration, endangering the stealth performance of underwater vehicles. In this study, several typical liquid lubricants, including liquid paraffin, tung oil (TO), dimethyl silicone oil (DSO), ionic liquid (IL), and hexamethylene diisocyanate (HDI) were selected as the surface coatings for nitrile butadiene rubber (NBR). Using a tribological test machine with a high-precision vibration acceleration sensor, as well as scanning electron microscopy (SEM) and other techniques, the tribological performance and mechanisms of the NBR samples coated with different lubricants were studied under various working conditions. The results showed that the liquid lubricant significantly reduced the coefficient of friction of the NBR at high rotational speeds by over 92.2%. The sample coated with HDI showed obvious tribochemical wear, and coating with the rest of the liquid lubricants decreased the specific wear rate of NBR. According to the friction-induced vibration signals, we found that an increase in loading aggravated friction-induced vibrations, and the vibrational energy was mainly concentrated in the low frequency range. The liquid paraffin and TO coatings barely changed the vibration characteristics of the NBR, while the other three lubricants produced more friction-induced self-oscillations. In conclusion, compared to the other liquid lubricants, TO exhibited the best tribological performance. The finding of this study further our understanding of the friction and vibration behaviours of polymer materials, providing a reliable basis for designing composite materials with good lubrication and vibration damping performance. • A feasible method for friction-induced vibration testing and analyzing is provided. • The tribological behavior database of liquid lubricants is improved. • Tung oil shows excellent lubricating performance. • The lubrication state is revealed by friction, wear and vibration together. [ABSTRACT FROM AUTHOR]

The nanopowders of Zn 2 SnO 4 were prepared via a hydrothermal method with different solution pH values. The influence of the pH value on the crystal structure, morphology, specific surface area, and gas sensing performance was comparatively investigated. The sensor prepared at the pH value of 13 showed the most promising integral ethanol gas sensing properties. At the optimal operating temperature of 300 °C, the sensor response increased linearly with ethanol concentration among the range of 5–200 ppm and showed a sensitivity of 0.213/ppm, a response/recovery time less than 15 s, and a high ethanol gas sensing selectivity against to acetone, methylbenzene and methanol. The related sensing mechanism was discussed based on the structural characteristics and the sensing properties. The results indicated that as-prepared Zn 2 SnO 4 nanopowders might be a promising candidate material for fabricating practical ethanol gas sensors. [ABSTRACT FROM AUTHOR]

High spatial frequency laser-induced periodic surface structures (high-spatial frequency LIPSSs; HSFLs), being beyond the optical diffraction limit, have attracted great attention due to their outstanding physical characteristics and potential for use in various fields. However, the formation mechanism of HSFL is still controversial, which severely limits their further applications. In this work, a novel numerical model with experimental support are proposed to explain the formation of HSFL through the existence of subsurface plasmon polaritons (Sub-SPPs) generated at the subsurface of the material. According to the results, the period of HSFL is determined by the competition between the propagation loss of Sub-SPP and the penetration loss of fs-laser pulses. Given this competition, the HSFL formation can be investigated through the optical method by introducing a typical dielectric constant and thereby avoiding the discussion of complex electronic behavior. The numerical simulation results are in good agreement with the experimental data acquired on various materials, thus evidencing the applicability of this model. This work provides a clear physical picture of HSFL formation, allowing one to develop state-of-the-art surface morphology controlling methods for potential manufacturing applications. [Display omitted] • Experimental support of sub-surface energy deposition in HSFL formation is obtained. • A novel numerical model is developed to explain HSFL formation. • The stability of HSFL period is analyzed through different types of losses. [ABSTRACT FROM AUTHOR]

In order to meet the needs of phase generated carrier (PGC) demodulation technology for interferometric fiber optic hydrophones, we proposed an optical microfiber all-optical phase modulator (OMAOPM) based on the photo-induced thermal phase shift effect, which can be used as a phase carrier generation component, so as to make the modulation efficiency and working bandwidth of this type of modulator satisfy the requirements of underwater acoustic signal demodulation applications. We analyzed the modulation principle of this modulator and optimized the structural parameters of the optical microfiber (OM) when the waist length and waist diameter of OM are 15 mm and 1.4 μm, respectively. The modulation amplitude of the modulator can reach 1 rad, which can meet the requirements of sensing applications. On this basis, the fiber optical hydrophone PGC-Atan demodulation system was constructed, and the simulated underwater acoustic signal test demodulation research was carried out. Experimental results showed that the system can demodulate underwater acoustic signals below 1 kHz. [ABSTRACT FROM AUTHOR]

Introduction: Chronic obstructive pulmonary disease (COPD) represents one of the leading causes of death worldwide. Published clinical trials suggest that the Chinese patent herbal medicine Shufeng Jiedu capsule (SFJD) is safe and may be effective for treating acute exacerbations of COPD (AECOPD). However, these effects have been reported with low or very low certainty evidence. This trial aims to evaluate the effectiveness and safety of SFJD for AECOPD., Methods and Analysis: This study is designed as a multicentre, randomised, double-blind, placebo-controlled trial. Three hundred patients with moderate or severe hospitalised AECOPD will be recruited in Beijing, Shanghai and Hefei. Participants will be randomly assigned to SFJD and usual care or placebo and usual care at a ratio of 1:1. SFJD and placebo will be administered orally four capsules three times daily for 7 consecutive days followed by an 8-week follow-up period. The primary outcome will be COPD symptom severity as measured by the EXAcerbation of Chronic Pulmonary Disease Tool score. Secondary outcomes include clinical symptoms, quality of life, length of hospital stay, a total dose of antibiotics, the frequency of recurrence of AECOPD, haematological biomarkers, death and adverse events. This study will answer the question of whether SFJD was safe to use and will improve symptoms in people with AECOPD, and will therefore reduce the necessity for antibiotics, the risk and duration of admission to hospital, and the risk of recurrence., Ethics and Dissemination: The ethics committee of the first affiliated hospital of Anhui Medical University, Beijing University of Chinese Medicine affiliated Dongzhimen hospital and fifth people's hospital of Shanghai Fudan University approved the study protocol. Informed written consent will be obtained from all the participants. The results of this trial will be disseminated at academic conferences and in peer-reviewed publications., Trial Registration Number: ISRCTN99049821., Competing Interests: Competing interests: The authors declare that they have the following possible conflicts of interest. However, these conflicts of interest did not actually influence the design, and the reporting of this study. The Beijing University of Chinese Medicine obtained funding from the Ministry of Science and Technology of the People’s Republic of China for a project investigating the use of Chinese herbal medicine for the treatment of chronic obstructive pulmonary disease. The other partners in the project are the University of Southampton, Anhui Jiren Pharmaceutical Co. (manufacturer of SFJD, providing the trial medication/placebo for free), and Phoenix Medical. The project is part of the “UK-China collaboration to tackle antimicrobial resistance”, funded by the UK and Chinese governments. Ruyu Xia, Yutong Fei, Lishan Zhang, Mengyuan Dai, Guanghe Fei and Jianping Liu received this research funding from Ministry of Science and Technology of the People’s Republic of China; Michael Moore, Merlin Willcox, and Xiaoyang Hu received this research funding from Innovate-UK., (© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: : During the coronavirus disease (COVID-19) pandemic, health care workers (HCWs) have faced a heightened risk of infection. Preventative measures are critical to mitigate the spread of COVID-19 and protect HCWs. Traditional Chinese medicine (TCM) has been recommended to prevent and treat COVID-19 in China. We conducted this survey to investigate the use of infection control behaviors, preventative and therapeutic interventions, and outcomes among HCWs during the surge of Omicron variant infections to explore the association of preventative measures with outcomes and to investigate the factors influencing the adoption of TCM as a preventative measure., Methods: : The questionnaire consisted of 23 sections with 154 questions intended for HCWs. The targeted respondents comprised all HCWs from Xiamen Hospital Affiliated of Beijing University of Chinese Medicine. The recruitment process was open between March 17 and June 1, 2022. Chi-square test was used to estimate the relationship between prevention and outcomes. Multivariable logistic regression was used to investigate factors influencing the use of TCM as a preventative measure., Results: : Among the 1122 participants who completed the questionnaire, 79.71% took preventative measures, including TCM (56.21%), physical activities (52.37%) and food supplements (26.99%). Xiamen preventative formula (a government-approved fixed prescription) (45.22%) and Lianhua Qingwen preparations (18.95%) were the most commonly used Chinese medicines. Thirty-six participants reported flu-like symptoms and three were diagnosed with COVID-19. Flu-like symptoms were not associated with prevention, vaccination, or TCM. Frontline working experience (OR = 0.61, 95% CI: 0.46-0.80), good knowledge of post-COVID-19 syndrome (OR = 0.57, 95% CI: 0.39-0.84), Western medicine qualifications (OR = 2.41, 95% CI: 1.51-3.86), nurses (OR = 1.70, 95% CI: 1.21-2.40), and medical technicians (OR = 2.27, 95% CI: 1.25-4.10) were associated with the willingness of using TCM as a preventative measure., Conclusion: : Complementary medicine, especially TCM, could be used for COVID-19 prevention. Knowledge of COVID-19 may prompt people to use TCM to prevent COVID-19. Multicenter studies and prospective cohort follow-up studies are needed to provide further insights into the use of TCM for COVID-19 management., Competing Interests: The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Xiaohua Pei reports article publishing charges was provided by Xiamen Municipal Bureau of Science and Technology. Co-responding author Jianping Liu is one of editorial board members of the European Journal of Integrative Medicine. Co-author Xiaoyang Hu is one of editorial board members of the European Journal of Integrative Medicine. Co-author Chun-li Lu is the managing editor of the European Journal of Integrative Medicine., (© 2023 Published by Elsevier GmbH.)

In the process of ocean exploration, highly accurate and sensitive measurements of seawater temperature and pressure significantly impact the study of seawater's physical, chemical, and biological processes. In this paper, three different package structures, V-shape, square-shape, and semicircle-shape, are designed and fabricated, and an optical microfiber coupler combined Sagnac loop (OMCSL) is encapsulated in these structures with polydimethylsiloxane (PDMS). Then, the temperature and pressure response characteristics of the OMCSL, under different package structures, are analyzed by simulation and experiment. The experimental results show that structural change hardly affects temperature sensitivity, and square-shape has the highest pressure sensitivity. In addition, with an input error of 1% F.S., temperature and pressure errors were calculated, which shows that a semicircle-shape structure can increase the angle between lines in the sensitivity matrix method (SMM), and reduce the effect of the input error, thus optimizing the ill-conditioned matrix. Finally, this paper shows that using the machine learning method (MLM) effectively improves demodulation accuracy. In conclusion, this paper proposes to optimize the ill-conditioned matrix problem in SMM demodulation by improving sensitivity with structural optimization, which essentially explains the cause of the large errors for multiparameter cross-sensitivity. In addition, this paper proposes to use the MLM to solve the problem of large errors in the SMM, which provides a new method to solve the problem of the ill-conditioned matrix in SMM demodulation. These have practical implications for engineering an all-optical sensor that can be used for detection in the ocean environment.

Metal coatings can protect the fragile optical fiber sensors and extend their life in harsh environments. However, simultaneous high-temperature strain sensing in a metal-coated optical fiber remains relatively unexplored. In this study, a nickel-coated fiber Bragg grating (FBG) cascaded with an air bubble cavity Fabry-Perot interferometer (FPI) fiber optic sensor was developed for simultaneous high temperature and strain sensing. The sensor was successfully tested at 545 °C for 0-1000 µɛ, and the characteristic matrix was used to decouple temperature and strain. The metal layer allows easy attachment to metal surfaces that operate at high temperatures, enabling sensor-object integration. As a result, the metal-coated cascaded optical fiber sensor has the potential to be used in real-world structural health monitoring.

Background: Duck viral hepatitis (DVH) has a significant economic impact on duck industry, and duck hepatitis A virus genotype 3 (DHAV-3) is the most prevalent pathogen of DVH in Asian duck industry. The detailed study connecting differentially expressed genes (DEGs) and the differential resistance to DHAV-3 have not been accurately described, although a large numbers of DEGs have been identified by transcriptomic studies., Results: Here, a resistant Pekin duck line (Z8R) and a susceptible Pekin duck line (Z8S) as models, high mortality and dramatically increased aspartate aminotransferase (AST), alanine aminotransferase (ALT) and the expression of immune-related genes of Z8S group were shown to be noticeable signs of cases caused by DHAV-3 infection. Compared with the control (Con) group, 1117 down-regulated DEGs and 612 up-regulated DEGs were found in the Z8S group and 37 down-regulated DEGs and 82 up-regulated DEGs were found in the Z8R group. Ultimately, the expression patterns of 10 DEGs were found to be diametrically opposite in Z8R and Z8S group. Functional analysis revealed that IFITM1 was associated with cell growth suppression, which was considered a key candidate gene. Results of flow cytometry showed that the conserved regions of IFITM1 (213-317 bp) could affected the cell cycle of duck embryo fibroblast (DEF) cells after infection with DHAV-3. Transcriptome and western blot analysis suggested that the CCND1, CCNE1 and CDK6 were significantly up-regulated in susceptible ducks by comparing with Con group., Conclusions: The hepatic injury and pathogenic outcomes caused by DHAV-3 infection were more severe in Z8S group compared to Z8R. Results of transcriptomics analysis and flow cytometry suggested that DHAV-3 infection can induce cell cycle changes that may be associated with IFITM1 expression level. These data will greatly enhance our understanding of the pathogenesis of DHAV-3 infection in ducklings and have implications for development of resistance breeding., Competing Interests: Declaration of Competing Interest No potential conflict of interest was reported by the author(s)., (Copyright © 2022. Published by Elsevier B.V.)

To improve the sensing performance of optical fiber magnetic field sensor based on magneto-refractive effect, a D-shaped photonic crystal fiber-surface plasmon resonance (PCF-SPR) sensor based on magneto-refractive effect is proposed and its magnetic field sensing characteristics are investigated. The designed D-shaped PCF has a core-analyte-gold structure. Within the D-shaped PCF, the side polishing surface is coated with the gold film and the special hole is sandwiched between the core and the gold film. To realize the high magnetic field sensitivity for the fiber SPR magnetic field sensor, the special hole is filled with magnetic fluid (MF). In this paper, we analyze the mode transmission characteristics and magnetic field sensing characteristics of this fiber sensor by finite element method. We also obtain a general rule for the optimization of PCF-SPR sensors by analyzing the dispersion curves, the energy of the surface plasmon polariton mode and the core mode on the sensing performance of the designed fiber sensor. The maximum refractive index sensitivity and magnetic field sensitivity of the optimized fiber are 59714.3 nm/RIU and 21750 pm/mT (50-130 Oe), respectively. Compared with optical fiber magnetic field sensors based on magneto-refractive effect reported previously, the magnetic field sensitivity in this paper is nearly two orders of magnitude higher and it can initially achieve nT magnitude magnetic field resolution and testing capability. The proposed fiber sensor has the advantages of simple structure, easy production, high sensitivity, and strong environmental adaptability. It not only improves the sensing performance of optical fiber magnetic field sensors, but also provides an ideal alternative platform for biosensors like microfluidics because of its high refractive index sensitivity and the special structure.

Based on the polymer encapsulation method, a compact structure and high-sensitivity temperature and pressure dual parametric sensor was developed in this paper by wrapping an optical microfiber coupler (OMC) in polydimethylsiloxane (PDMS). Benefiting from the stable chemical properties and good optical field control ability of PDMS, the sensor showed good stability and repeatability. The dependence of the sensor sensitivity on wavelength, temperature, and pressure was experimentally investigated. The results showed that the temperature and pressure sensitivity could reach -2.283 nm/°C and 3.301 nm/Mpa in the C-band range. To overcome the cross-sensitivity of sensor temperature and pressure, a sensitivity matrix was established to realize dual-parameter simultaneous demodulation. In addition, the pressure repeatability of the sensor was tested. Based on this, the sensitivity matrix was further calibrated to reduce the error and improve the accuracy of demodulation. Finally, we also designed a protective shell for the sensor to meet the requirements of practical marine applications. Compared with other existing types of optical fiber sensors, this sensor has the advantages of simple fabrication, high sensitivity, and environmental adaptability, and has great potential for application in the field of marine environmental monitoring.

To the best of our knowledge, we present what we believe is a novel approach for fading noise reduction in distributed acoustic sensing (DAS). Rayleigh signals in multiple optical modes are collected by a phase-sensitive optical time-domain reflectometry system with a diversity detection scheme. An optimal weighted average algorithm is proposed to synthesize the phase demodulated from the Rayleigh signals, leading to the aggregate phase that presents acoustic signals with optimal fading noise reduction. The validity of the proposed approach is experimentally confirmed by comparison of the fading noise along a 12.8 km sensing fiber in a conventional DAS system and a DAS system that employs the proposed approach.

Osteoporosis (OP) is a systemic bone metabolic disease. Promotion of osteoblast proliferation and inhibition of cell apoptosis may be helpful for the prevention and clinical treatment of OP. In the current study, we focused on the expression changes and clinical values of lncRNA ROR and miR-145-5p in OP clinical serum samples, and investigated the interactive modulation effect of ROR/miR-145-5p on osteoblast function. Serum samples were obtained from 82 OP patients and 79 healthy individuals. MC3T3-E1 was applied for the cell experiments. Levels of lncRNA ROR and miR-145-5p were detected using qRT-PCR. Transient transfection was performed to regulate gene levels in cells, and cell proliferation and apoptosis were detected. A reciprocal correlation between lncRNA ROR and miR-145-5p was explored. LncRNA ROR was downregulated, and miR-145-5p was overexpressed in OP patients. The combined diagnosis of ROR and miR-145-5p showed good diagnostic value for OP. ROR knockdown promoted the MC3T3-E1 cell apoptosis and inhibited cell proliferation. Luciferase reporting assay verified the target relationship between ROR and miR-145-5p. MiR-145-5p downregulation reversed ROR silence mediated effect on MC3T3-E1 cell proliferation and apoptosis. LncRNA ROR is downregulated and miR-145-5p is highly expressed in OP patients. ROR knockdown may inhibit osteoblast proliferation via targeting miR-145-5p. It may provide a theoretical basis and experimental basis for ROR to be a potential target for the treatment of OP.