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With the aim to explore the use of tree pruning waste as replacement material in papermaking, a study was conducted to investigate the effect of soda pulping concentration on the tear resistance and surface morphology of the fabricated papers. By varying the sodium hydroxide concentration from 5% to 25%, tree pruning waste papers with different tear resistance and surface morphology were fabricated. The tree pruning waste papers with the optimum tear resistance (73049.68 mN) was produced when the pulping medium was prepared at 20% sodium hydroxide concentration. As confirmed by the morphology study, the pulp fibres with improved interlocking surface morphology was produced at 20% sodium hydroxide concentration. Beyond that, fibre fibrillation had took place and exerted negative impact on the tear resistance of the papers. The present study confirms the use of tree pruning waste as an alternative in papermaking. Nonetheless, the soda pulping concentration must be properly regulated in order to maximize the performance of the fabricated paper products.

Tremella fuciformis is an important edible mushroom that has been widely cultivated and used as food and medicinal ingredient in traditional Chinese medicine. In the past decades, many researchers have reported that T. fuciformis polysaccharides (TPS) possess various bioactivities, including anti-tumor, immunomodulatory, anti-oxidation, anti-aging, repairing brain memory impairment, anti-inflammatory, hypoglycemic and hypocholesterolemic. The structural characteristic of TPS has also been extensively investigated using advanced modern analytical technologies such as NMR, GC-MS, LC-MS and FT-IR to dissect the structure-activity relationship (SAR) of the TPS biomacromolecule. This article reviews the recent progress in the extraction, purification, structural characterization and applications of TPS.

As one of the key technologies, preparation of silicon nanospheres is very important for developing the new types of silicon based solar cells. In this paper, with the establishment of a novel electrical discharge machining (EDM) system and the raw material of heavy doped mono-crystalline silicon (0.01Ω•cm), silicon nanospheres of which diameter are ranging from 25nm to 280nm have been successfully prepared by using EDM method. The micro surface topography and the elements composition are analyzed by the SEM and the EDS methods respectively. The formation mechanism of nanospheres has also been studied.

To understand the relationship between lodging resistance and chemical component contents in culms and leaf sheaths of rice, the physical strength and maximum bearing capacity of culm, and the contents and amounts of potassium (K), silicon (Si) and soluble sugars in culms and leaf sheaths were investigated using four japonica rice varieties with different lodging resistance characteristics during grain filling. There were significant differences in the total amounts of K, Si and soluble sugars in culms and leaf sheaths among the tested rice varieties. The difference in the total amount of Si was greater than that of K or soluble sugars. The physical strength and maximum bearing capacity of culm continuously decreased from heading to ripening, with a rapid decrease at the dough stage. However, the contents and total amounts of K and Si in culms and the Si content in leaf sheaths gradually increased and an accumulation of K and Si in culms was exhibited, whereas the content and total amount of K and the total amount of Si in leaf sheaths gradually decreased and an exportation of K and Si in leaf sheaths was presented. The physical strength was positively and significantly correlated with the total amounts of K and Si in culms during grain filling except that at the heading stage, the total amount of soluble sugars in culms at the heading and milky stages, the total amounts of Si and soluble sugars in leaf sheaths at the heading stage, the total amount of K in leaf sheaths at the heading and milky stages, and the maximum bearing capacity during grain filling. It is suggested that the lodging resistance of japonica rice would be improved by increasing the amount of soluble sugars in plants at the early filling stage, and enhancing the amount of Si in plants during grain filling through topdressing Si fertilizer at the early filling stage.

The progenies differed in amylose and protein contents in grains, which derived from a rice cross, Dongnong 423×Toukei 180, were used to study changes in the activities of ADP-glucose pyrophosphorylase (AGPP), soluble starch synthetase (SSS), starch branching enzyme (SBE) and glutamine synthetase (GS) in rice grains during grain filling. The activities of AGPP, SSS and SBE gradually increased and then declined as a single-peak curve with the process of grain filling in the progenies with high and low amylose contents in grains. The progenies with high amylose content peaked earlier in the AGPP, SSS and SBE activities and had higher AGPP, SSS and SBE activities at the early grain filling stage than those with low amylose content. The GS activity peaked earlier and was higher at the late stage of grain filling in the progenies with high protein content than in those with low protein content. It is suggested that the activities of key enzymes for starch synthesis and glutamine synthetase could be changed in oriented breeding for amylose and protein contents in grains.

Angiotensin-(1-7) [Ang-(1-7)], a heptapeptide mainly generated from cleavage of AngI and AngII, possesses physiological and pharmacological properties, including anti-inflammatory and antidiabetic properties. Activation of the phosphoinositide 3-kinase and protein kinase B (PI3K/Akt) signaling pathway has been confirmed to participate in cardioprotection against hyperglycaemia-induced injury. The aim of the present study was to test the hypothesis that Ang-(1-7) protects H9c2 cardiomyoblast cells against high glucose (HG)-induced injury by activating the PI3K/Akt pathway. To examine this hypothesis, H9c2 cells were treated with 35 mmol/l (mM) glucose (HG) for 24 h to establish a HG-induced cardiomyocyte injury model. The cells were co-treated with 1 μmol/l (μM) Ang-(1-7) and 35 mM glucose. The findings of the present study demonstrated that exposure of H9c2 cells to HG for 24 h markedly induced injury, as evidenced by an increase in the percentage of apoptotic cells, generation of reactive oxygen species and level of inflammatory cytokines, as well as a decline in cell viability and mitochondrial luminosity. These injuries were significantly attenuated by co-treatment of the cells with Ang-(1-7) and HG. In addition, PI3K/Akt phosphorylation was suppressed by HG treatment, but this effect was abolished when the H9c2 cells were co-treated with Ang-(1-7) and HG. Furthermore, the cardioprotection of Ang-(1-7) against HG-induced injury in H9c2 cardiomyoblasts was highly attenuated in the presence of either D-Ala7-Ang-(1-7) (A-779, an antagonist of the Mas receptor) or LY294002 (an inhibitor of PI3K/Akt). In conclusion, the present study provided new evidence that Ang-(1-7) protects H9c2 cardiomyoblasts against HG-induced injury by activating the PI3K/Akt signaling pathway.

Objective: Chilling tolerance of salicylic acid (SA) in banana seedlings (Musa acuminata cv., Williams 8818) was investigated by changes in ultrastructure in this study. Methods: Light and electron microscope observation. Results: Pretreatment with 0.5 mmol/L SA under normal growth conditions (30/22 °C) by foliar spray and root irrigation resulted in many changes in ultrastructure of banana cells, such as cells separation from palisade parenchymas, the appearance of crevices in cell walls, the swelling of grana and stromal thylakoids, and a reduction in the number of starch granules. These results implied that SA treatment at 30/22 °C could be a type of stress. During 3 d of exposure to 7 °C chilling stress under low light, however, cell ultrastructure of SA-pretreated banana seedlings showed less deterioration than those of control seedlings (distilled water-pretreated). Conclusion: SA could provide some protection for cell structure of chilling-stressed banana seedling.

Pretreatment in the chilling-sensitive banana seedlings by spraying 0.5 mM salicylic acid (SA) hydroponic solution onto leaves and irrigating to roots at 30/22 °C for 1 day induced an increase of chilling tolerance during subsequent 5 °C chilling stress. Pretreatment of 0.5 mM SA treatment at 30/22 °C for 1 day did not result in a remarkable change in superoxide dismutases (SOD) activity, but reduced catalases (CAT) and ascorbate peroxidase (APX) activities, and increased peroxidases (POX) activity. During a 5 °C chilling stress period, however, SA pretreatment caused an activation of SOD, CAT and APX activities, while it did not change POX activity. Different effects of SA on protective enzyme activities could be associated with hydrogen peroxide (H 2 O 2 ) metabolism. Measurement of H 2 O 2 levels and staining with diaminobenzidine (DAB) indicated that SA pretreatment at 30/22 °C resulted in H 2 O 2 accumulation; however, during subsequent 5 °C chilling stress, SA pretreatment reduced H 2 O 2 overproduction. The results suggested that H 2 O 2 metabolism could participate in enhanced chilling tolerance of SA in banana plants.

Hydroxyapatite has achieved significant application in orthopedic and dental implants due to its excellent biocompatibility. Sintered hydroxyapatites showed significant dissolution, however, after their immersion in water or simulated body fluid (SBF). This grain boundary dissolution, even in pure hydroxyapatites, resulted in grain separation at the surfaces, and finally, in fracture. In this study, hydroxyapatite ceramics containing apatite-wollastonite (AW) or calcium silicate (SG) glass ceramics as additives were prepared to prevent the dissolution. AW and SG glass ceramics were added at 0-7 wt% and powder-compacted uniaxially followed by firing at moisture conditions. The glass phase was incorporated into the hydroxyapatite to act as a sintering aid, followed by crystallization, to improve the mechanical properties without reducing the biocompatibility. As seen in the results of the dissolution test, a significant amount of damage was reduced even after more than 14 days. TEM and SEM showed no decomposition of HA to the secondary phase, and the fracture toughness increased, becoming even higher than that of the commercial hydroxyapatite.