In order to analyze the improvement of fish resource,the trawl net and gill net were used in the background survey and investigation in the artificial reef area and control area of the east of corner was discussed in ...In order to analyze the improvement of fish resource,the trawl net and gill net were used in the background survey and investigation in the artificial reef area and control area of the east of corner was discussed in Zhelang Shanwei in January 2003 and April 2010 respectively.Margalef species richness index,Shannon-Winener diversity index and Pileou uniformity index were chosen to analyze the multiformity of biological population and community structure.Resource density index of trawl net investigation and catch rate of gill net were chosen to estimate the variance of biomass.The results of the trawl net showed that the resources density of the artificial area increased by 3.078 times,and numbers of species increased by 1.875 times,squilla being the dominant group instead of the fish,and the first dominant species being squilla oratoria(Oratosquilla oratoria),which increased by 4.372 times before the artificial reef dropped.The results of the gill net showed that the catch rate of the artificial area increased by 12.043 times,numbers of species increased by 1.333 times,the dominant group was fish,it increased greatly,the first dominant species was golden small fish(Sardinella aurita),which increased by 13.035 times before the artificial reef dropped.Both the results of trawl net and gill net indicated that the effect of fish assemblage were evident,and the community structure had improved greatly.It showed a wonderful effect on conservation and assemblage of fishes resource.The artificial reefs developed a new resource enhancement system in the east corner of Zhelang Shanwei accomplished basically.展开更多
The interface characteristics of cyanide tailings are different from those of the raw ore. In this study, valuable elements could not be thoroughly recovered via the flotation of cyanide tailings from Shandong, China....The interface characteristics of cyanide tailings are different from those of the raw ore. In this study, valuable elements could not be thoroughly recovered via the flotation of cyanide tailings from Shandong, China. The interface and floatability of these tailings were investig- ated by phase analysis and flotation tests. The chalcopyrite in the cyanide tailings was fine and had a porous surface. The floatability of 68% chalcopyrite was similar to that of galena in the presence of a collector. A layer of fine galena particles compactly wrapped the chalcopyrite. The chalcopyrite recovery sharply decreased as the nonpolar oil residue in cyanide tailings was extracted using alcohol;however, this removal had no effect on the galena. The remaining chalcopyrite in the flotation tailings was covered with an oxidation layer consisting of O, Fe, S, Pb, Cu, Zn, and Si.展开更多
Matrix stiffness has been demonstrated in many studies to adjust the biological behaviors of mesenchymal stem cells (MSCs). However, in the initial phase of bone restore, MSCs will encounter a hypoxic microenvironment...Matrix stiffness has been demonstrated in many studies to adjust the biological behaviors of mesenchymal stem cells (MSCs). However, in the initial phase of bone restore, MSCs will encounter a hypoxic microenvironment. Studying the connection existing between the matrix stiffness and biological behavior of MSCs under hypoxic condition can better simulate the microenvironment at the prime period of bone repairment. In this work, three-dimensional (3D) decalcified bone scaffolds with diverse stiffness (high stiffness (66.06 ± 27.83) MPa, medium stiffness (26.90 ± 13.16) MPa, and low stiffness (0.67 ± 0.14) MPa) but same microstructure have been prepared by controlling decalcification time. In addition, the decellularized bone scaffold was regard as control group and its stiffness was (230.93 ± 72.65) MPa. The viability, proliferation, infiltration, and osteogenic differentiation of MSCs seeded into these 3D demineralized bone scaffolds were systematically investigated under 100 μM CoCl2-simulated hypoxic and normoxic environments. The results showed that the viability, proliferation, and extracellular matrix (ECM) secretion of MSCs had no significant difference on scaffolds with diverse stiffness but the degree of collagen deposition of MSCs gradually increased with the increase of scaffold stiffness both under normoxia and hypoxia. Compared to normoxia, the viability, proliferation, ECM secretion, vascular endothelial growth factor (VEGF) expression, and osteogenis of MSCs on the scaffolds with the same stiffness were evidently inhibited by hypoxia. Additionally, under hypoxic condition, the expression of VEGF and hypoxia inducible factor 1α(HIF-1α) in MSCs on the low stiffness scaffold was markedly increased comparing to those on other groups. In summary, we found that the low stiffness scaffold can improved the proliferation and osteoginic differentiation of MSCs under hypoxic environment, which may help to explore efficient methods for bone defect repairing.展开更多
基金Supported by National Public Industry Scientific Research Program(201003068)National"863"Program(2006AA100303)National Financial Program(2009-2012)
文摘In order to analyze the improvement of fish resource,the trawl net and gill net were used in the background survey and investigation in the artificial reef area and control area of the east of corner was discussed in Zhelang Shanwei in January 2003 and April 2010 respectively.Margalef species richness index,Shannon-Winener diversity index and Pileou uniformity index were chosen to analyze the multiformity of biological population and community structure.Resource density index of trawl net investigation and catch rate of gill net were chosen to estimate the variance of biomass.The results of the trawl net showed that the resources density of the artificial area increased by 3.078 times,and numbers of species increased by 1.875 times,squilla being the dominant group instead of the fish,and the first dominant species being squilla oratoria(Oratosquilla oratoria),which increased by 4.372 times before the artificial reef dropped.The results of the gill net showed that the catch rate of the artificial area increased by 12.043 times,numbers of species increased by 1.333 times,the dominant group was fish,it increased greatly,the first dominant species was golden small fish(Sardinella aurita),which increased by 13.035 times before the artificial reef dropped.Both the results of trawl net and gill net indicated that the effect of fish assemblage were evident,and the community structure had improved greatly.It showed a wonderful effect on conservation and assemblage of fishes resource.The artificial reefs developed a new resource enhancement system in the east corner of Zhelang Shanwei accomplished basically.
基金the National Key R&D Program of China(Nos.2018YFC1902002 and 2018YFC1902003)the Special Fund for the National Natur-al Science Foundation of China(No.U1608254)the En-terprise Research Program(No.2014-0-1-02129).
文摘The interface characteristics of cyanide tailings are different from those of the raw ore. In this study, valuable elements could not be thoroughly recovered via the flotation of cyanide tailings from Shandong, China. The interface and floatability of these tailings were investig- ated by phase analysis and flotation tests. The chalcopyrite in the cyanide tailings was fine and had a porous surface. The floatability of 68% chalcopyrite was similar to that of galena in the presence of a collector. A layer of fine galena particles compactly wrapped the chalcopyrite. The chalcopyrite recovery sharply decreased as the nonpolar oil residue in cyanide tailings was extracted using alcohol;however, this removal had no effect on the galena. The remaining chalcopyrite in the flotation tailings was covered with an oxidation layer consisting of O, Fe, S, Pb, Cu, Zn, and Si.
基金the National Natural Science Foundation of China (Grants 11702043 and 11672051 and 11702044)Fundamental Research Funds for the Central Universities (Grant 2018CDQYSG0015).
文摘Matrix stiffness has been demonstrated in many studies to adjust the biological behaviors of mesenchymal stem cells (MSCs). However, in the initial phase of bone restore, MSCs will encounter a hypoxic microenvironment. Studying the connection existing between the matrix stiffness and biological behavior of MSCs under hypoxic condition can better simulate the microenvironment at the prime period of bone repairment. In this work, three-dimensional (3D) decalcified bone scaffolds with diverse stiffness (high stiffness (66.06 ± 27.83) MPa, medium stiffness (26.90 ± 13.16) MPa, and low stiffness (0.67 ± 0.14) MPa) but same microstructure have been prepared by controlling decalcification time. In addition, the decellularized bone scaffold was regard as control group and its stiffness was (230.93 ± 72.65) MPa. The viability, proliferation, infiltration, and osteogenic differentiation of MSCs seeded into these 3D demineralized bone scaffolds were systematically investigated under 100 μM CoCl2-simulated hypoxic and normoxic environments. The results showed that the viability, proliferation, and extracellular matrix (ECM) secretion of MSCs had no significant difference on scaffolds with diverse stiffness but the degree of collagen deposition of MSCs gradually increased with the increase of scaffold stiffness both under normoxia and hypoxia. Compared to normoxia, the viability, proliferation, ECM secretion, vascular endothelial growth factor (VEGF) expression, and osteogenis of MSCs on the scaffolds with the same stiffness were evidently inhibited by hypoxia. Additionally, under hypoxic condition, the expression of VEGF and hypoxia inducible factor 1α(HIF-1α) in MSCs on the low stiffness scaffold was markedly increased comparing to those on other groups. In summary, we found that the low stiffness scaffold can improved the proliferation and osteoginic differentiation of MSCs under hypoxic environment, which may help to explore efficient methods for bone defect repairing.
