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In the current study, the effects of fermentation manners on the structure and immunomodulatory activity of polysaccharide in longan wine or vinegar were investigated. Compared to longan polysaccharide (CP1), polysaccharide in longan wine (CP2) or vinegar (CP3 and CP4) had smaller molecular weights, and was consisted of more mannose, arabinose, rhamnose, galactose and less glucose. After purification, the major fraction (P1-P4) was obtained from CP1-CP4, respectively. The structures and immunoregulatory activities of P1-P4 were characterized. Fermentation and purification were favorable to increase the immunoregulatory activities of P2-P4, which were contributed to their different structural features. The structure-activity relationship analysis indicated that molecular weight, mannose, rhamnose, glucuronic acid, glucose and arabinose were significantly associated with the cytokines secretion. Compared with other polysaccharides, P3 displayed better immunomodulatory activity due to its lower molecular weight, lower contents of rhamnose and glucose, and higher levels of mannose and arabinose by activating MAPK and PI3K/Akt signaling pathways.

Atmospheric plasma spraying (APS) of silicon carbide (SiC) is a challenging task due to the severe decomposition behaviour of the SiC. Previous studies, which utilized APS technique, mixed SiC powder with metals and/or metal oxides to prepare SiC coating. None of them sprayed silica gel-coated SiC and examined the characteristics of the coatings. In this work, silica gel-coated SiC, sodium dodecyl sulfate (SDS) enhanced silica gel-coated SiC, and the combination of alumina (Al2O3) and SiC were prepared and then deposited onto a titanium (Ti) plate by APS. Scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), adhesion and acid resistance test were performed to analyse the characteristics of modified powders and coatings. We found that compared to Commercial-SiC coatings, all the modified SiC coatings not only increase the coating thickness but also enhance the adhesion force between the coating and substrate; furthermore, the SDS-modified sample exhibits good sulfuric acid (H2SO4) resistance. On the other hand, samples containing Al2O3 showed a significant increase in coating thickness and adhesion force, despite a bit lower acid resistance. In sum, we believe that compared to silica-gel coated samples, Al2O3 contained samples are more suitable for industrial application.

In this study, a facile method was developed to fabricate MoS2 nanosheet-enhanced Pebax-MoS2 mixed matrix membranes (MMMs) for CO2 capture. A super mixer was introduced to ensure the homogeneity of the as-prepared solutions, and a far more efficient method of Pebax-MoS2 MMM preparation was accordingly achieved. The membrane structures were observed by SEM, and membrane crystallinity was examined by XRD and DSC. FTIR and Raman spectroscopy were utilized to verify that the Pebax-MoS2 membranes were well prepared. The gas permeability results showed that the Pebax membrane doped with 4.76 wt % MoS2 nanosheets had the best performance, with a CO2 permeability of 67.05 Barrer and CO2/N2 selectivity of 90.61. The molecular simulation technique used for the Pebax-MoS2 MMMs was first adopted by our group to investigate CO2 solubility and CO2/N2 solubility selectivity. The simulation results demonstrated the strong affinity of CO2 for the added MoS2, consequently contributing to high CO2/N2 selectivity, and were highly correlated with the experimental results. Pebax-1657-based MMMs incorporating MoS2 nanosheets can be therefore be considered a promising alternative for CO2 capture applications.

A combinatorial batch code was defined by Paterson, Stinson and Wei as a purely combinatorial description of batch codes, which were first introduced by Ishai, Kushilevitz, Ostrovsky and Sahai. It is a system consisting of m subsets of an n -element set such that any k distinct elements can be retrieved by reading at most one (or in general, t ) elements from each subset and the number of total elements in m subsets is N . For given parameters n , k , m , the goal is to determine the minimum N , denoted by N ( n , k , m ) . So far, for k ≥ 5 and m + 3 ≤ n m k − 2 , precise values of N ( n , k , m ) have not been established except for some special parameters. In this paper, we determine the N ( n , 5 , m ) for n ≤ ⌊ m 2 4 ⌋ + ⌈ m ∕ 2 ⌉ 3 + ⌊ m ∕ 2 ⌋ 3 , and give a bound on N ( n , 5 , m ) for ⌊ m 2 4 ⌋ + ⌈ m ∕ 2 ⌉ 3 + ⌊ m ∕ 2 ⌋ 3 n ≤ m 3 , which is tight for some m , n .

Fish are the primary source of protein and docosahexaenoic acid (DHA) for pregnant women and children, but methylmercury (MeHg) pollution is the potential hazard of fish consumption. In risk assessments, the bio-accessibility of MeHg is usually assumed to be 100%, which could lead to overestimation of dietary exposure.An existing PBTK model was adapted to estimate parameters of the bio-accessibility based on MeHg exposure data from a cohort of 397 Chinese pregnant women. The posterior distributions of parameters were determined by using the ABC - MCMC. RMSEP and Spearman's rank correlation coefficients (Rho) were calculated to determine the goodness of model fitting. The Monte Carlo analysis was performed for the parameter distributions to estimate the model variability.The median of daily MeHg intake and maternal MeHg levels were 0.018 μg/kg bw and 3.01 μg/kg in the early and middle terms of pregnancy. The estimated bio-accessibility of freshwater fish, marine fish and others were 46.1, 17.3 and 58.2%, separately. The RMSEP improved from 11.18 to 2.54 and the Rho improved from 0.19 to 0.22 after bio-accessibility optimization. The model variability was estimated to be 2.6.The bio-accessibility estimated in this study was comparable to that determined in previous in vitro studies. The optimized model could improve the prediction performance on the MeHg body burden by dietary exposure.

Applying a porous hydroxyapatite (HA) coating on a titanium substrate is a widely used method to increase the biocompatibility and osteogenic potential of human embryonic palatal mesenchymal (HEPM) pre-osteoblasts. Thermal spraying is one of the most prevalent methods used to coat HA on titanium substrates due to its ease in processing and ability to produce coatings with good adherence, which affect positively the surface topography and coating performance. The objective of this work is to enhance the biocompatibility and osteogenic potential of HA coatings on titanium substrates. HA was first synthesized and then coated onto a titanium substrate by two distinct methods, i.e., the dry coating method and the wet coating method. The phase content was evaluated by X-ray diffraction (XRD). The particle morphology was observed by scanning electron microscopy (SEM). HEPM pre-osteoblasts were used to test the cell-material interaction in vitro, and thereafter, an alkaline phosphatase (ALP) test was conducted. The wet coating method enhanced the specific surface area, which in turn increased the cell proliferation on HA-coated titanium substrates. The in vitro test demonstrated that wet coatings resulted in enhanced cell attachment and ALP activity. This study shows that spraying HA using the wet coating method is a technique that can produce potentially bioactive bone-regeneration implants.

Dispersion of carbon fibers in the cement matrix remains a hot topic in the preparation of carbon fiber-reinforced cement-based composites (CFRC) because it affects greatly both the mechanical and electrical properties of the composites. In this work, a new dispersant hydroxyethyl cellulose was used with the aids of pre-dispersion by ultrasonic wave to realize the uniform distribution of chopped carbon fibers in the cement matrix. The fracture surface of the prepared CFRC was observed by scanning electron microscopy, the elemental distribution was investigated by energy dispersive spectroscopy, and the components was analyzed by X-ray diffraction. Influences of carbon fiber lengths and contents, water/cement weight ratio, molding process, curing time, and silica fume content over the conductivity of the CFRC composites were studied. The mechanism of conductivity was discussed. Results shown that the electrical resistivity intended to decrease with the increasing of carbon fiber contents. The mass fraction 0.6% of carbon fibers was a turning point. The concentration of hydroxyethyl cellulose between 1.66% and 1.86% was mostly beneficial for the dispersion of carbon fibers. The resistivity was increased first and decreased then with the increase of water/cement ratio. When the CFRC sample was prepared by the vibrating pressing method, the resistivity of the sample was reduced far greatly than that of the sample by the vibrating method. The incorporation of silica fume into the CFRC composites exerted not only a good effect on the dispersion of carbon fibers, but also increased the density of the composites to further influence the conductivity of the CFRC.

Cyanate ester (CE) resin was modified in a multi-component way using the technology of conjugated tri-component interpenetrating polymer networks (CTC-IPN). Experimental results showed that the three components in the modified composite existed undependably and they interweaved irregularly in the structure of IPN to form a unique supermolecule structure. The analysis by differential scanning calorimetry (DSC) indicated that the T g of the modified CE was increased by 22 °C, compared with the T g prior to modification. When the amount of an initiator was 0.3% or 0.4% and concurrently the ratio of PST/PMMA/CE was 15/15/85, the flexural strength and the impact strength reached the maximum values. Compared with those of pure CE, the flexural strength was increased by 22.65% and the impact strength by 94.99%, respectively.

For the first time, a 3D Digital Twin virtual model of a hollow fiber membrane was established based on real data. The filtration process of ultrafine particles by using a hollow fiber membrane was also successfully analyzed with multiscale simulation. In this study, we investigated the difference between scanning electron microscopy (SEM) and X-ray computed tomography (X-CT) with regard to membrane analysis. In addition, the pore size distribution was calculated based on two different modules: the Granulometry module and the Porosimetry module. The results of the latter showed greater accuracy than the results of the experimental measurements. In the flow analysis, the velocity and pressure distribution were also obtained through simulations to investigate transport phenomena in membrane filtration. Moreover, the unprecedented technique of particle tracing was applied and successfully provided detailed information regarding how the particles were captured. Evaluations of the membrane performance, pressure drop, and filtration efficiency were conducted and compared to the experimental results with 2.25% and 0.01% errors. Our work showed the potential of the construction of 3D virtual models. These models not only exhibited high accuracy but also provided detailed information that is difficult to obtain via experiments. Through a combination of image analysis and multiscale simulation, a platform to evaluate membrane performance with high reliability and efficiency was established.

In this study, a thin membrane with vertically aligned mesoporous silica nanochannels was modified with long silane group molecules (E-MSTF-LTA) supported on an anodic aluminum oxide (AAO) for organic solvent nanofiltration (OSN). The ultrathin thickness, low tortuosity, ordered vertical channels and super-organophilic surface of E-MSTF-LTA endow it with an ultrahigh ethanol permeance (110 LMH/bar) over current state-of-the-art OSN membranes and a high acetone permeance of 360 LMH/bar. Furthermore, a 99% rejection of Evans blue (EB) was demonstrated, and a cut-off of approximately 660 Da was achieved. Besides, the modified Hagen-Poiseuille (HP) equation was applied to evaluate the theoretical permeance, which is consistent with the experimental results. To explore in depth the underlying principle behind the OSN performance of the vertically aligned E-MSTF-LTA membrane, the parameters, including the solvent viscosity, total Hansen solubility, solvent diameter, and solvent polarity were introduced to evaluate their influence on the permeance, while for solute transport behavior, the impact of the size exclusion effect on the solute rejection rate was examined. The results show that the viscosity is the critical factor for determining the solvent permeation, while the size exclusion effect dominates solute rejection. These findings open up a way to design next-generation vertically aligned OSN membranes and shed light on the OSN performance, both empirically and theoretically, using this system.

In this work, a zeolitic imidazolate framework-8 (ZIF-8)/polyvinyl alcohol (PVA) mixed matrix membrane (MMM) was coated onto α-aluminum oxide (α-Al2O3) hollow fibers for ethanol dehydration by utilizing the pervaporation technique. ZIF-8/PVA solution was prepared via a drying-free, water-based method to obtain a uniform distribution MMM. Before coating the MMM onto the hollow fiber, a pristine PVA solution was first dip-coated onto hollow fiber as a gutter layer to prevent phase separation. Different weight ratios of ZIF-8-loaded MMMs were prepared. The results showed that at high ZIF-8 loading (39 wt %), a high permeate flux (685 g/m2 h) and high separation factor (4821) can be observed. Furthermore, compared with free-standing ZIF-8/PVA MMMs, hollow fiber supported ZIF-8/PVA MMMs exhibit a thinner coating thickness but higher pervaporation separation index (approximately 1.5–2 times). The main contribution of this study is not only fabricated the high loading ZIF-8/PVA composite membrane with enhanced performance, but also coated onto the hollow fiber membrane which opens a gate for scale-up production.

Quasi-strongly regular graphs are a combinatorial generalization of strongly regular graphs. A quasi-strongly regular graph of grade 2 with parameters ( n , k , a ; c 1 , c 2 ) is a k -regular graph on n vertices such that any two adjacent vertices have a common neighbours, any two non-adjacent vertices have c 1 or c 2 common neighbours, and for each c i ( i = 1 , 2 ) , there exists a pair of non-adjacent vertices sharing c i common neighbours. If a quasi-strongly regular graph of grade 2 is neither a strongly regular graph nor a Deza graph, then it is called a strictly quasi-strongly regular graph. In this paper, we characterize strictly quasi-strongly regular graphs with parameters satisfying c 1 = k − 1 .

The surface topography of implants plays an important role in affecting the behaviour of osteoblasts. Previous research has demonstrated that porous hydroxyapatite (HAp) coating surfaces fabricated by vapour-assisted flame spraying enhances osteoblast attachment and differentiation, but flame spraying cannot supply sufficient power for fabricating porous surfaces without cracks. To solve this problem, porous HAp coatings were deposited on titanium (Ti) discs using a novel vapour-induced pore-forming atmospheric plasma spraying (VIPF-APS) technique with a higher amount of energy. A water reservoir was placed behind the Ti discs to serve as the vapour source. Ti discs with three different mean pore diameters, namely, ATi (2.65 μm), BTi (15.65 μm), and CTi (35.33 μm), were used, and the HAp coatings that were deposited on these three discs using the VIPF-APS technique were denoted HAp-ATi, HAp-BTi, and HAp-CTi, respectively. For comparison, the conventional APS technique was used to deposit HAp on ATi, and this sample was named HAp-APS/ATi. The results showed that the VIPF-APS technique effectively produced porous HAp coatings, whereas the conventional APS technique yielded dense coatings that are unfavourable for applications. These porous coatings further contributed to higher osteoblast proliferation and distinctive alkaline phosphatase activity. The VIPF-APS technique thus has great potential for producing bioactive coatings that can be used in implants.

In this study, an environmentally friendly method was developed to fabricate N-doped few-layer graphene (N-FLG)/Pebax mixed-matrix membranes (MMMs) for CO2 capture. A supermixer was introduced to ensure homogeneity of the N-FLG in the Pebax solution, and a highly efficient method of N-FLG/Pebax MMM preparation was achieved. The membrane structures were analyzed by SEM, while the N-FLG morphology was examined by SEM, AFM, XPS and EDX. A detailed molecular simulation was applied to mimic and predict the behavior of and interaction between membranes and gas molecules. Through the simulation, an independent analysis of transport-related characteristics, such as diffusivity, solubility and permeability, was achieved. In addition, the simulation indicated that the affinity of N-FLG for CO2 molecules improves the CO2 capture performance, that the membranes are solubility-dependent when prepared with low contents of N-FLG and that the effect of diffusivity increases as the addition of N-GO increases above 5 wt%. The simulation results were highly correlated with the experimental results, while the experimental gas permeability results showed that the optimal performance of N-FLG/Pebax MMM was obtained with the addition of 4 wt% N-FLG, providing CO2 permeability and CO2/N2 selectivity of 239.8 Barrer and 95.5, respectively. Pebax-1657-based MMMs incorporating N-FLG nanosheets fabricated by an environmentally friendly method can therefore be considered a promising material for CO2 capture applications.

Strontium (Sr) and magnesium (Mg) have been reported to promote osteoblastic cell proliferation and to accelerate bone formation. However, the biofunctional effect on osseointegration caused by coating dental implants with hydroxyapatite (HA) incorporating both of these elements has not been investigated to date. The aim of this study was to examine bone formation and osseointegration in Sr- and Mg-doped HA-coated titanium implants. In this study, the flame-spraying technique was used to deposit Sr- and Mg-doped HA onto titanium discs and implants. The biocompatibility and alkaline phosphatase (ALP) activity of human embryonic palatal mesenchymal pre-osteoblasts on titanium discs was evaluated. In addition, the expression of the osteogenesis gene and the protein expression of Runt-related transcription factor 2 (RUNX2), osteopontin (OPN), and osteocalcin (OCN) on titanium discs were determined by using real-time polymerase chain reaction assays, Western blot analysis, and enzyme-linked immunosorbent assays. Ultimately, the effects of Sr- and Mg-doped HA on the osseointegration of implants were examined in beagle dogs. The results showed that of the groups tested, the 5Sr5Mg-HA group exhibited the highest biocompatibility, ALP activity, and mRNA and protein expression of RUNX2, OPN, and OCN. Prominent new bone ingrowth with osteoblasts and osteoid tissue was found in the 5Sr5Mg-HA group at 4 weeks and 8 weeks. In addition, the highest bone-to-implant contact ratio was found in the 5Sr5Mg-HA group compared to other groups at 8 weeks in beagle dogs. The results show the potential of using 5Sr5Mg-HA coating on dental implants for enhanced osseointegration. Statement of Significance Osseointegration is assessed according to the extent of bone-to-implant contact and is an indication of implant success. This study is the first to report that flame-sprayed Sr- and Mg-doped HA coatings on titanium surfaces enhance osseointegration and new bone apposition in a beagle dog model. Therefore, the use of titanium implants incorporating Sr and Mg might be advantageous for patients with a low bone density.