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Using selected sepiolite (SEP) and biochar (BC) as contrasts, we investigated the effects of a new cross-linked modified chitin (CC) on the bioavailability of Pb and Cd in soils, the yield of rice, and the absorption and accumulation of Pb and Cd in different parts of rice plants in a field environment. We hope this study provides the basis for the application of this material to improve soil fertility, and a direction for further soil improvement studies. A field experiment was carried out in 2015-2016 on selected Pb- and Cd-contaminated rice fields in Linghai, Liaoning. The changes in soil pH and available Pb and Cd in the soil were analyzed after the rice was harvested(October 2016). The effects of different treatments on the growth traits and yield of rice, the absorption of Pb and Cd by rice roots, stems and leaves, and grains were compared. The results showed that adding 167-333 kg·hm-2 CC could increase the soil pH value by 0.36-0.45 units, decreasing the contents of available Pb and Cd in the soil by 46.39%-64.01% and 29.73%-43.24% respectively (P<0.05). This treatment significantly reduced the Pb and Cd contents in all parts of rice (P<0.05) compared to conventional fertilization; Pb and Cd contents in different parts of rice were significantly reduced (P<0.05) by 16.09%-38.14% and 21.22%-31.38% in the root, 19.17%-46.92% and 25.66%-45.34% in the stem and leaf, and 29.47%-58.25% and 44.75%-64.02% in the grain, respectively. The treatment of adding 333 kg·hm-2 CC (CC-2) reduced the contents of Pb and Cd in rice grains to 0.2041±0.011 mg·kg-1 and 0.1922±0.021 mg·kg-1, respectively, which were lower than or close to the limit values of Pb and Cd in rice (0.20 mg·kg-1) as per GB 2762-2005. Compared to conventional fertilization, SEP treatment, and BC treatment, without adding any amendments, the yield per mu of rice under CC treatment increased by 33.6-47, 27.6-44, and 8.67-34.77 kg, respectively. The effect of CC-2 treatment on yield was the most obvious; the yield of rice per mu increased by 47 kg, and the yield increase rate was 8.59%. The ability of CC to repair soil contaminated by Pb and Cd and to reduce the contents of Pb and Cd in rice was not weaker than that of SEP and BC. The CC treatment also controlled the migration and redistribution of Pb and Cd in soil-rice systems, and significantly increased the yield of rice. It has good potential to ensure the safe production of rice.

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One new dimeric diterpenoid, 8(14)-enyl-pimar-2'(3')-en-4'(18')-en-15'(16')-endolabr- 16,15,2',3'-oxoan-16-one (1) and five known terpenoids: Tagalsin C (2), Tagalsin I (3), lup-20(29)-ene-3ß,28-diol (4), 3-oxolup-20(29)-en-28-oic acid (5) and 28-hydroxylup- 20(29)-en-3-one (6) were isolated from the roots of the mangrove plant Ceriops tagal. Their structures and relative stereochemistry were elucidated by means of extensive NMR, IR and MS analysis. The antifouling activity against larval settlement of the barnacle Balanus albicostatus were evaluated using capsaicin as a positive control. All these terpenoids exhibited antifouling activity against cyprid larvae of the barnacle without significant toxicity. The structure-activity relationship results demonstrated that the order of antifouling activity was diterpenoid (Compound 2) > triterpenoid (Compounds 4, 5 and 6) > dimeric diterpenoid (Compounds 1 and 3). The functional groups on the C-28 position of lupane triterpenoid significantly affect the antifouling activity. The diterpenoid dimmer with two identical diterpenoid subunits might display more potent antifouling activity than one with two different diterpenoid subunits. The stability test showed that Compounds 2, 4, 5 and 6 remained stable over 2-month exposure under filtered seawater.

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Five new pimarane diterpenoids 1-5 were synthesized using ent-8(14)-pimarene-15R,16-diol as starting material. The structures were elucidated by means of extensive NMR and MS analysis. The antifouling activity against larval settlement of the barnacle Balanus albicostatus were evaluated using capsaicin as a positive control. Compounds 1-3 and 5 showed more potent antifouling activity than capsaicin. Compound 5, which exhibited almost the same antifouling activity as starting material, showed better stability than starting material. These compounds all showed antifouling activity in a non-toxic way against larval settlement of the barnacle B. albicostatus. Analysis of structure-activity relationships (SAR) demonstrated that the substituents on the C-15 and C-16 position of pimarane diterpenoid were responsible for the antifouling activity.

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To investigate the mechanism of meridians in circulating qi and blood and its role in medical model of TCM. To clarify the cell model of meridian structure formation and the significance in both its mechanism of regulating qi and blood and TCM model formation, by using the result of modern life science researches. With its unique mechanism formation and through its organizational structure, the meridian structure manages to regulate the state of qi and blood circulation in the tissues and organs by affecting the bio-activity and the specific bio-active substance transmission of mast cells, which also plays an important role in the medical model formation of TCM.

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In the present paper, the characteristics of acupoints in composition and their functional activities are discussed based on related domestic and abroad investigated results achieved in this area. Niche microenvironment of adult stem cells and correlative special differentiated cells are assembled, like gathering in caves, under the complex ation of network junctions of biological stress. A hypothesis of trinity is put forward to explain the construction and functional activities of acupoints.

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Recognition of traditional Chinese medicine for the structures of channels and collaterals is possibly related with the tactics of human early general medical study, characterized by "inner", sub-micro, entirety, etc. The mechanisms are possibly involved in direct communication pathway of the cell junction (specially keeping the relevant cellular direct communication relation in individual development), the extra-cellular matrix stress network system and its biophysical message transmission--force--meridian signs transformation--inter-cellular massage integration, and "generalization" of the structures and activities of channels and collaterals in acupuncture serum phenomenon, etc. Thus, the hypothesis of multi-factors about channel structures-mechanisms is proposed.

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A new atisane-type diterpene, ent-16alpha-hydroxy-atisane-3,4-lactone (4) and three known diterpenes, ent-16alpha-hydroxy-atisane-3-one (1), ent-atisane-3beta,16alpha-diol (2), ent-3,4-seco-16alpha-hydroxyatis- 4(19)-en -3-oic acid (3) were isolated from the bark of the mangrove plant Excoecaria agallocha. Their structures and relative stereochemistry were elucidated by means of extensive NMR and MS analysis. Compound 3 exhibited significant anti-microfouling activity against the adherence of Pseudomonas pseudoalcaligenes, with an EC(50) value of 0.54+/-0.01 ppm.

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The new diterpene methoxy-ent-8(14)-pimarenely-15-one (1) and three known metabolites: ent-8(14)-pimarene-15R,16-diol (2), stigmasterol (3) and beta-sitosterol (4), were isolated from the roots of the mangrove plant Ceriops tagal. Their structures and relative stereochemistry were elucidated by means of extensive NMR, IR and MS analysis. Compounds 1, 2, 3 and 4 exhibited significant antifouling activities against cyprid larvae of the barnacle Balanus albicostatus Pilsbry, with EC(50) values of 0.32 +/- 0.01, 0.04 +/- 0.00,4.05 +/- 0.15 and 18.47 +/- 0.40 microg/cm(2), respectively, whereas their toxicities towards cyprids were very low, with LC(50 )values all above 10 microg/cm(2).

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