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The structure parameter of the forward osmosis membrane has been defined as the characteristics of the support membrane, not related to the separation layer. Therefore, studies for improving the performance of the forward osmosis (FO) membranes have been focused on the optimization of the support structure. This study demonstrates that the separation thin-film polyamide (PA) layer has a strong impact on the performance of the FO membrane thus the structure parameters (S). We intentionally utilized a polyethersulfone hollow fiber substrate and two types of active separation skin were prepared at the inner surface: the first MPD/TMC and the second by adding triethylamine (TEA) into the aqueous phase during the interfacial polymerization (IP). By adding TEA, a rough PA layer with a leaf-like structure and a high crosslinking degree was obtained followed with high FO flux and low reverse salt flux attributed to the increased effective filtration area and crosslinking degree. The structure parameter of the FO membrane was reduced from 0.78 mm (for MPD/TMC system) to 0.45 mm (for MPD-TEA/TMC system). The result indicated that for the same substrate, lower structure parameter corresponded to the skin layer with higher permeance and rejection. This study confirmed that the structure parameter is more an inherent property of the entire TFC FO membrane than the character of the porous substrate. Future design for FO membranes needs to regulate the substrate, but more importantly to optimize the separation layer. • An approaching ratio (α) was designed as a simple guideline for control the structure parameter of FO membranes. • Diethylene glycol was used as the nonsolvent to control the approaching ratio. • Lowest structure parameter and highest FO performance were obtained at α = 50 %. • The optimized TFC membrane is of practical interest for lithium concentration. [ABSTRACT FROM AUTHOR]

At present, there are some problems in the process of human motion recognition, such as poor timeliness and low fault tolerance rate. How to effectively identify the motion process accurately has become a hot spot in the optimization system. In the existing research studies, the recognition accuracy is not very good and the response time is long. To end this issue, the paper proposed an information processing system and optimization method of human motion recognition based on the GA-BP neural network algorithm. Firstly, a human motion recognition system based on dynamic capture recognition technology is designed, which realizes the recognition of motion information from common postures such as action span, speed change, motion trajectory, and other aspects in the process of human motion. Secondly, the proposed algorithm is used to comprehensively analyse and evaluate the motion state. Finally, experiments are designed to verify and analyse the results. Compared to some baseline methods in human motion recognition information systems, the system in this paper based on the GA-BP neural network algorithm has the advantages of higher data accuracy and response speed, which can quickly and accurately identify the muscle group change in the process of human motion, and it can also provide customized motion suggestions based on the results. [ABSTRACT FROM AUTHOR]

Objective To explore the correlation between metabolic syndrome (MS) and noise-induced hearing loss (NIHL) in noise-exposed workers. Methods Using the convenient sampling method, a total of 850 male noise-exposed workers in an automobile manufacturing enterprise were studied. The questionnaire survey and occupational health examination were combined to collect general demographic data, physical examination data, and other information. According to the results of high-frequency hearing loss, the noise-exposed workers were divided into the hearing loss group (326 workers) and the normal hearing group (524 workers). The single-factor analysis was used to compare the above data differences between the two groups. The binary multiple-factor logistic regression model was used to analyze the influencing factors of NIHL in noise-exposed workers. Results The non-compliance rate of noise intensity in the enterprise was 39.47% (15/38), with the highest occurrences in the welding and painting posts. The morbidity of hearing loss was 38.35% (326/850), and the MS morbidity was 27.53% (234/850). The frequency of obesity, high-level triglyceride, high-level fasting blood glucose, hypertension, MS,and the contact noise level in the hearing loss group were higher than those in the normal hearing group (P < 0.05). The results of multiple-factor logistic regression showed that, compared with the workers with a noise exposure duration ≤ 5 years, the risk of NIHL in the workers with a noise exposure duration of 11 - 15 years or > 15 years increased to 1.553 and 1.727 times, respectively (P < 0.001). Compared with the workers without MS, the risk of NIHL in the workers with MS increased to 1.863 times (P < 0.001). The risk of NIHL increases by 1.567 times for each 1 dB(A) increase in noise level (P < 0.001). Conclusions There was a correlation between MS and NIHL. In addition to emphasizing control of noise level in the workplace, attention should also be paid to adopting a low-sugar, low-salt, and low-sodium diet, reducing the intake of saturated fatty acids, and strengthening physical exercise to effectively control the blood pressure, blood sugar, and blood lipid levels of workers so as to reduce the risk of NIHL. [ABSTRACT FROM AUTHOR]

Objective: This study aims to compare the efficacy of intra-articular injections of hyaluronic acid (HA), platelet-rich plasma (PRP), and platelet-rich fibrin (PRF) for treating temporomandibular disorders (TMDs) and summarize their mechanisms of action. Methods: Randomized controlled trials (RCTs) published until November 13, 2021, were identified using electronic and manual searches. Each study was evaluated for the risk of bias using the Cochrane risk of bias tool. The studies found via searches were categorized by follow-up time (1, 3, or 6 months). Evidence quality was graded according to the GRADE system. Results: Twelve RCTs were included that involved 421 patients with TMD. The network meta-analysis showed that all treatment groups improved compared to the placebo groups in terms of pain and maximal mouth opening (MMO). For pain evaluated via the visual analog scale, PRF exhibited better analgesic effects than PRP or HA after 1 and 3 months. PRP appeared to be more effective than PRF was after 6 months but there were no statistically significant differences between the two. For MMO, the effect of PRP was superior to those of PRF and HA after 1 month. However, after 3 and 6 months, PRF provided more encouraging results in improving MMO. Conclusion: PRP and PRF exhibited similar short-term efficacy in treating TMD, while PRF was more advantageous in terms of long-term efficacy. Therefore, PRF was recommended for treating TMD. [ABSTRACT FROM AUTHOR]

Direct preparation of dialysate from tap water based on osmotic dilution is beneficial for home hemodialysis which requires a defect-free forward osmosis (FO) membrane module. This report introduced a new vacuum-assisted interfacial polymerization (VAIP) process for optimal distribution of the aqueous phase and a well-controlled IP using dialyzer membranes. We demonstrated statistically that the vacuum-assisted process is beneficial for the preparation of integral FO modules with multiple fine fibers due to the good distribution of the aqueous phase. The as-prepared FO module displayed a low structural parameter (262 μm), an acceptable water flux (17.6 L m−2 h−1), and a low specific reverse salt flux (0.16 g/L) using deionized (DI) water as the feed and 1 M NaCl as the draw in AL-FS mode. Direct dialysate preparation from tap water using the FO module was presented and modeled with a good fit. The work showcases a new FO module based on dialyzer and its potential applications in the medical field. [Display omitted] • Tap water was used to directly dilute dialysis concentrate using dialyzer FO module. • Novel vacuum-assisted interfacial polymerization was employed to prepare the TFC HF FO membrane. • Hemodialysis is available at home using tap water and dialyzer FO module. [ABSTRACT FROM AUTHOR]

Rejection of single salts or ions is a basic and crucial characteristic of nanofiltration (NF) membranes. The simple and most pursued method to quantify the salt concentration has been via conductivity measurement. Pitfalls exist when ions hydrolysis or feed water contains monovalent ions. This could be explained in two possible scenarios: (1) easily hydrolyzed single salts form low charged ions and reduce feed pH, resulting in increased permeate conductivity and low nominal rejection; (2) for membranes with high multivalent ion rejections (>99%) or the concentration of target ions in feed is low, conductivity measurement results in low rejection due to the passage of monovalent ions if deionized water is used for the feed solution. A correction formula by subtracting the concentration of monovalent ions in water to obtain an accurate rejection value is proposed. This work provides an accurate, simple and robust evaluation of rejection for NF membranes, which promotes fair comparison of performance in literature, reliable analysis of separation mechanisms as well as a precise determination of product purity. • Cations hydrolysis form low-charged ions and reduce feed pH, resulting in low rejection tested by conductivity measurement. • The passage of monovalent ions results in low rejection for membranes with high multivalent ion rejections. • A correction formula was proposed by subtracting the concentration of monovalent ions for accurate rejection. [ABSTRACT FROM AUTHOR]

Fiber-reinforced resin-based composites (FRC) are in line with the concept of sustainable development owing to their excellent performance and have gradually replaced traditional friction materials. Notably, the wear of composites only accounts for about 15% of whole thickness when reaching their service life, so the surface characteristics are important factors affecting comprehensive properties. To make clear the relationship between surface characteristics and properties, especially under oil lubrication, the composites with different surface characteristics have been obtained by introducing constrain and free curing process during composites preparation. Results indicate that the surface porosity increases from 36.3% to 61.2% with the extension of free curing time, and the changes in surface roughness of different composites are consistent with surface porosity, showing an increasing trend. A more uniform and better-connected pore structure is conducive to enhancing the thermal conductivity of FRC. When the surface porosity is about 41.0%, the composite exhibits excellent tensile and interlaminar shear strength owning to better interface bonding. In addition, the dynamic friction coefficient (μ d) gradually improved as the surface porosity increases, and the stability of μ d is related to the change of surface roughness under continuous braking, the slight change of surface roughness corresponds to a more stable μ d. The wear rate of composites first decreases from 0.73 × 10−8 cm3/J (Y1) to 0.50 × 10−8 cm3/J (Y2) and then increases to 1.57 × 10−8 cm3/J (Y6). When the surface porosity is 40–50%, the composite exhibits excellent wear resistance. Most importantly, this study provides solid basic knowledge of the structural design of composites, which is favorable for obtaining expected mechanical and tribological performances. [Display omitted] [ABSTRACT FROM AUTHOR]

The dominant market for lithium-ion batteries (LIBs) in China has driven lithium chemicals with foreseeable growth in demand. Lithium extraction from salt-lake brine in China with high Mg2+/Li+ ratio has become one of the key challenges in the separation of Mg2+ and Li+. In this study, we introduce here an unprecedented, highly permselective nanofiltration hollow fiber membrane prepared by layer-by-layer (LBL) deposition as a novel alternative for Mg2+/Li+ separation. Poly(styrene sulfonate) and poly(allylamine hydrochloride) were deposited alternatively on a tailor-made ultrafiltration hollow fiber support and crosslinking with glutaric dialdehyde. The pure water permeability of LBL NF membrane was 18.4 L m−2 h−1 bar−1. Under the synergistic effect of size sieving and Donnan exclusion effect, it also achieved promising results when tested with simulated brine. The rejection rate of Mg2+ was as high as 99%, and the rejection rate of Li+ was as low as −60%, with a separation factor of 74 was observed, setting a record of permselectivity for Mg2+/Li+ separation for engineerable membranes. This research has paved a new road for the engineering application of LBL nanofiltration membranes for mono and bivalent ion separation. • LBL nanofiltration hollow fiber membrane was used for Mg2+/Li+ separation for the first time. • Exceedingly high permselectivity was observed using PSS/PAH pairs in LBL assembly. • Size sieving was identified as the key factor for Mg2+/Li+ separation. [ABSTRACT FROM AUTHOR]