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Chestnut bur is an agro-waste material generated in the chestnut production. It is a tannin-rich lignocellulosic material which might be a promising raw material for low-formaldehyde composite particleboard production when using urea–formaldehyde (UF) as bonding adhesive. In this study, the characteristics of chestnut bur were analyzed to assess its application value for composite panel. Five-type particleboards were manufactured from the mixture of chestnut bur/poplar particles with the weight ratios of 0/100, 25/75, 50/50, 75/25 and 100/0, UF resin was used as bonding adhesive. The effects of the addition amount of chestnut bur on the physical, mechanical properties and formaldehyde emission of particleboard were studied. The results showed as follows: (1) chestnut bur showed low cellulose, hemicelluloses and lignin contents, but high extractives and ash contents compared with poplar wood. Chestnut bur and poplar wood had the similar fiber morphology. (2) Composite board with relatively good performances could be manufactured with mix particles of chestnut bur and poplar wood. With the increasing of chestnut bur content, the mechanical properties of the composite board decreased, whereas the dimensional stability increased. (3) The total phenol content in the chestnut bur was as high as 13.79%. The phenolic substance in the chestnut burs could react with free formaldehyde. Hence, the free formaldehyde emission of particleboard was effectively reduced. In summary, waste chestnut bur is a suitable material which can not only be utilized as the base material, but also a natural free formaldehyde scavenger for composite particleboard production.

Tea polyphenols (TP) are a widely acknowledged bioactive natural product, however, low stability and bioavailability have restricted their application in many fields. To enhance the stability and bioavailability of TP under certain moderate conditions, encapsulation technique was applied. Kappa–Carrageenan (KCG) was initially degraded to a lower molecular weight KCG (LKCG) by H2O2, and was selected as wall material to coat TP. The obtained LKCG (Mn = 13,009.5) revealed narrow dispersed fragments (DPI = 1.14). FTIR and NMR results demonstrated that the main chemical structure of KCG remained unchanged after degradation. Subsequently, LK-CG and TP were mixed and homogenized to form LK-CG-TP microspheres. SEM images of the microspheres revealed a regular spherical shape and smooth surface with a mean diameter of 5–10 μM. TG and DSC analysis indicated that LK-CG-TP microspheres exhibited better thermal stability as compared to free TP. The release profile of LK-CG-TP in simulated gastric fluid (SGF) showed a slowly release capacity during the tested 180 min with the final release rate of 88.1% after digestion. Furthermore, in vitro DPPH radical scavenging experiments revealed that LK-CG-TP had an enhanced DPPH scavenging rate as compared to equal concentration of free TP. These results indicated that LK-CG-TP microspheres were feasible for protection and delivery of TP and might have extensive potential applications in other bioactive components.

The associations of long-term exposure to various constituents of fine particulate matter (≤2.5 μm in aerodynamic diameter, PM2.5) air pollution with lung function were not clearly elucidated in developing countries. The aim was to evaluate the associations of long-term exposure to main constituents of PM2.5 with lung function in China. This is a nationwide, cross-sectional analysis among 50,991 study participants from the China Pulmonary Health study. Multivariable linear regression models were used to obtain differences of forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), FEV1/FVC, peak expiratory flow (PEF), and forced expiratory flow at 25–75% of exhaled FVC (FEF25-75%) associated with an interquartile range (IQR) change of PM2.5 or its constituents. Residential annual PM2.5 levels varied from 26 μg/m3 to 92 μg/m3 (average: 53 μg/m3). An IQR increase of PM2.5 concentrations was associated with lower FEV1 (19.82 mL, 95% CI: 11.30–28.33), FVC (17.45 mL, 95% CI: 7.16–27.74), PEF (86.64 mL/s, 95% CI: 59.77–113.52), and FEF25-75% (31.93 mL/s, 95% CI: 16.64–47.22). Black carbon, organic matter, ammonium, sulfate, and nitrate were negatively associated with most lung function indicators, with organic matter and nitrate showing consistently larger magnitude of associations than PM2.5 mass. This large-scale study provides first-hand epidemiological evidence that long-term exposure to ambient PM2.5 and some constituents, especially organic matter and nitrate, were associated with lower large- and small- airway function.

To evaluate the effects of biomass pre-pyrolysis and pyrolysis temperature on magnetic biochar (MB) properties, MB composites were fabricated from rattan sawdust (RS) and rattan charcoal (RC) through simple iron salt impregnation and subsequent pyrolysis under different temperatures (600–900 °C). Characterization analysis revealed that pyrolysis procedure greatly affects the physicochemical properties of final products. Magnetite dominates the crystal phases of the MB pyrolyzed at 600–800 °C and the Fe (III) species in MBS (MB from RS) are easier to be reduced into wustite. Raising the pyrolysis temperature to 900 °C or increasing the molar ratio of Fe2+–Fe3+ are effective ways to promote the formation of α-iron for both MBS and MBC (MB from RC). Although the MBS yield is lower than that of MBC, the magnetic media in MBS dispersed more uniform on the surface of the biochar matrix. The saturation magnetization decreased from 600 to 800 °C and increased afterward from 800 to 900 °C for MBS, which raised continuously for MBC.

Adoptive transfer of bone marrow‑derived mesenchymal stem cells (BMSCs) significantly alleviates smoking‑induced chronic obstructive pulmonary disease (COPD) in rats. Considering the critical roles of T cells during COPD development, the present study aimed to further identify the molecular mechanisms underlying the antiproliferative effect of BMSCs on splenic T cells isolated from rats following chronic exposure to nicotine. Splenic T cells were co‑cultured with rat BMSCs at various ratios and subsequently, T‑cell proliferation was measured using the Cell Counting Kit‑8 assay. The effects of the inducible nitric oxide synthase (iNOS) inhibitor N‑nitro‑L‑arginine methylester (L‑NAME) and short hairpin (sh)RNA‑lentivirus‑mediated knockdown of iNOS in BMSCs on T‑cell proliferation were evaluated. The expression levels of iNOS and STAT5 phosphorylation in BMSCs and T cells, respectively, were assessed by reverse transcription‑quantitative PCR and western blotting. A higher ratio of BMSCs to T cells resulted in increased inhibition of T‑cell proliferation; therefore, the ratio of 1:20 was selected for further in vitro experiments. At a dose of 5 µM, L‑NAME displayed the strongest ability to reverse the antiproliferative effects of BMSCs in the co‑culture system. Both L‑NAME treatment and shRNA‑mediated knockdown of iNOS expression significantly decreased the suppressive effects of BMSCs, downregulated iNOS expression at the mRNA and protein levels in BMSCs, and enhanced STAT5 phosphorylation in T cells. BMSCs inhibited the proliferation of nicotine‑exposed T cells, which was associated with iNOS expression in BMSCs and decreased STAT5 phosphorylation in T cells. The present study indicated the potential mechanisms underlying the beneficial effects of BMSC infusion in patients with chronic smoking‑induced COPD and emphysema.

Bronchial asthma is the most common chronic respiratory disease. Chronic airway inflammation, airflow restriction and airway hyper-responsiveness are its main manifestations. In recent decades, the prevalence and mortality of asthma have been increasing all over the world, which seriously threatens public health. Research suggests that air pollution is associated with the increased incidence of asthma. PM2.5 is one of the most complex pollutants in the atmospheric environment and harmful to human health. It is related to the incidence of asthma. However, the molecular mechanism of PM2.5 in the development of asthma is still unclear. In this study, we established a mouse model of asthma using CRE to observe the effect of PM2.5 on the symptoms of asthmatic mice and its possible molecular mechanism. The results showed that PM2.5 could significantly increase airway resistance and pulmonary inflammation, increase the number of inflammatory cells, eosinophils, macrophages, neutrophils and lymphocytes in bronchoalveolar lavage fluid in asthmatic mice. Moreover, PM2.5 could reduce the contents of antioxidant enzymes such as CAT, GSH, GSH-Px and T-SOD in lung tissue of mice, and increase the ROS level. PM2.5 can promote the expression of microRNA-206 in lung tissue of mice. miR-206 can target the 3'-UTR of SOD1 to inhibit SOD1 expression, which leads to the increase of ROS level and aggravates pulmonary inflammatory response and asthma symptoms in asthmatic mice. This study found the possible molecular mechanism of PM2.5 aggravating asthma, and miR-206 may be a potential target for asthma treatment.

Binderless ramie stem particleboard was prepared by steam injection pressing in this paper. Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TG), high performance liquid chromatography analysis (HPLC) and specific surface area (BET) were used to analyze the forming mechanism. The results show that the number of active hydroxyl in cellulose molecule was increased by the synergistic effect of the water and heat, which could form hydrogen bonds (O-H…H), Van der Waals forces to enhance mechanical properties of resulting board. In addition, part of hemicellulose in ramie stem particles were hydrolyzed by the synergistic effect of the water and heat, and the hydrolysate could be subjected to polycondensation reaction to generate polycondensation furan resin which was similar to adhesives. The hydrolysate also could be subjected to polycondensation reaction with the lignin having a phenolic hydroxyl structure to generate a kind of condensation compound which was similar to phenolic resin adhesive. Moreover, the lignin in ramie stem particles were fully expanded and part of lignin was evenly distributed by the synergistic effect of the water and heat, which could improve the physical and mechanical properties of binderless particleboard to some extent.

The development of natural adhesives derived from non-fossil resources is very important for the future. In this study, by taking sugarcane bagasse as the raw material, without using any synthetic resin but adding some eco-friendly additives (citric acid and sucrose), low density particleboards were successfully developed. The effects of board density and additive contents on the physical and mechanical properties of the boards were investigated. The bonding mechanism was observed by Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). The results showed that the low density bagasse particleboard had good mechanical properties and dimensional stability relative to its low board density. The modulus of rupture (MOR) and the thickness swelling (TS) values increased with increasing board density. The board with a density of higher than 0.40 g/cm³ and manufactured at 15% additive content can meet the requirements of the Chinese national forestry industry standard LY/T 1718-2007 (2007). Based on the results of the FTIR spectra, the additive not only increased the hydrogen bond but also the molecular linkage force (C-O-C). X-ray diffraction showed the relationship between crystallinity of cellulose and the strength of particleboard.

We investigated optimum self-bonding conditions of kenaf core composites manufactured by steam treatment, and discussed on the roles of cinnamic acids in the self-bonding mechanism. The presence of cinnamic acids in the kenaf core and its composites were analyzed by pyrolysis gas chromatography-mass spectrophotometry in the presence of tetramethyl ammonium hydroxide (TMAH/Py-GC-MS). The results showed that the optimum bonding properties of kenaf core composites were achieved under these conditions: steam pressure of 0.8–1.0 MPa and pressing time of 10–15 min were able to provide shear strength of 0.40–0.42 MPa while having 2–5% of weight loss. Lignin analysis showed that steam-treated kenaf core composites had a lower proportion of syringyl- to guaiacyl-derived moieties and also cinnamic acids to guaiacyl-derived moieties than its native counterpart. The results indicated that some parts of the ester-linked cinnamic acids were also cleaved due to the degradation of hemicelluloses and lignin during steam treatment. Based on these results, it was concluded that in addition to three main components, the cinnamic acid was also suggested to participate in the self-bonding mechanism of non-wood lignocellulosic binderless boards.

The effects of chemical changes in kenaf core binderless particleboards on the bonding performance and thickness swelling of boards were investigated by chemical and spectroscopic analyses. Mild steam-injection treatments (0.6–1.0 MPa) caused significant degradation of hemicelluloses, lignin, and cellulose. Conventional hot pressing caused a lower degree of degradation of the chemical components. The hot-pressed kenaf core board without any binders showed poor bonding performance. Thus, it was found that partial degradation of the three major chemical components of the kenaf core by mild steam-injection treatment increased the bonding performance and dimensional stability of the binderless boards, and gave better quality binderless boards than those made by hot-pressing treatments.

This work presents a series of experimental tests on new practical approaches in membrane design to improve extraction capacity and rate. We chose an extraction system involving Aliquat 336 as the extractant and Cd(II) as the metal ion to be extracted to demonstrate these new approaches. The core element in the new membrane assembly was the extractant loaded sintered glass filter. This membrane assembly provided a large interface area between the extractant and the aqueous solution containing metal ions. By recycling the aqueous solution through the membrane assembly, the extraction rate was significantly improved. The membrane assembly also offered good extraction capacity.

A major concern in solvent extraction processes is the loss of extractant into the aqueous phase due to its slight solubility in the aqueous phase. Similarly, in membrane extraction processes, extractant loss through extractant leakage from the membrane into the aqueous phase is also a concern. Several published membrane extraction studies using Aliquat 336 as the extractant, have expressed this concern, but none has studied extractant leakage quantitatively. It is the authors’ opinion that the extractant leakage should be considered as a technical parameter of a membrane. In our laboratory active progress has been made in using Aliquat 336 ‘entangled’ into the polymer membranes to remove heavy metal ions from wastewater samples. In this work, we studied the loss of Aliquat 336 from the point of view of its solubility in aqueous solutions. The results showed that the solubilities of Aliquat 336 in an aqueous phase acidified with 2 M HCl is about 0.1 g/100 m/ of the solution. This figure provides a useful guideline for evaluating the leakage of the Aliquat 336 extractant from the membranes.

Clara cell protein (CC16) is a well-known anti-inflammatory protein secreted by the epithelial Clara cells of the airways. It is involved in the development of airway inflammatory diseases such as chronic obstructive pulmonary disease and asthma. Previous studies suggest that CC16 gene transfer suppresses expression of interleukin (IL)-8 in bronchial epithelial cells. However, its role in the function of these cells during inflammation is not well understood. In this study, we evaluated the effect of CC16 on the expression of matrix metalloproteinase (MMP)-9 in lipopolysaccharide (LPS)-stimulated rat tracheal epithelial cells and its underlying molecular mechanisms. We generated recombinant rat CC16 protein (rCC16) which was bioactive in inhibiting the activity of phospholipase A2. rCC16 inhibited LPS-induced MMP-9 expression at both mRNA and protein levels in a concentration-dependent (0–2 µg/mL) manner, as demonstrated by real time RT-PCR, ELISA, and zymography assays. Gene transcription and DNA binding studies demonstrated that rCC16 suppressed LPS-induced NF-κB activation and its binding of gene promoters as identified by luciferase reporter and gel mobility shift assays, respectively. Western blotting and immunofluorescence staining analyses further revealed that rCC16 concentration dependently inhibited the effects of LPS on nuclear increase and cytosol reduction of NF-κB, on the phosphorylation and reduction of NF-κB inhibitory IκBα, and on p38 MAPK-dependent NF-κB activation by phosphorylation at Ser276 of its p65 subunit. These data indicate that inhibition of LPS-mediated NF-κB activation by rCC16 involves both translocation- and phosphorylation-dependent signaling pathways. When the tracheal epithelial cells were pretreated with chlorpromazine, an inhibitor of clathrin-mediated endocytosis, cellular uptake of rCC16 and its inhibition of LPS-induced NF-κB nuclear translocation and also MMP-9 production were significantly abolished. Taken together, our data suggest that clathrin-mediated uptake of rCC16 suppresses LPS-mediated inflammatory MMP-9 production through inactivation of NF-κB and p38 MAPK pathways in tracheal epithelial cells.

Nowadays wood-based panels are widely used in furniture manufacture and interior decoration. They would release formaldehyde during the service for most of them being bonded with the formaldehyde-based adhesive. The formaldehyde does a great harm to people's health. Measurements should be taken to lower the formaldehyde emission. Several methods were introduced in this paper to solve the problem. There is a well defined market for the environmental friendly wood-based panel production.