Glyptosternoid fishes are a group of sisorid catfishes living in torrents of rivers mainly originating from the Qinghai-Tibet Plateau. Based on our survey in the Drung River Basin, seven collecting sites were investig...Glyptosternoid fishes are a group of sisorid catfishes living in torrents of rivers mainly originating from the Qinghai-Tibet Plateau. Based on our survey in the Drung River Basin, seven collecting sites were investigated and 271 glyptosternoid fishes caught belong to three species （Pareuchiloglanis kamengensis, Exostoma labiatum and Oreoglanis mocropterus）. Features of the distribution of the three catfishes were assessed. More individuals of E. labiatum were caught in the lower reaches of the Drung River with fast water velocity and it might be more adapted to a torrent habitat. The relationships between standard length （L） and weight （W） for P. kamengensis, E. labiatum and O. macropterus were also studied, and the parameter b of the L-W relationship （W = aL^b） ranged between 2. 8201 and 3. 0131. From the present study, all the three catfish species grow allometrically and the growth type of E. labiatum is the closest to a symmetrical one.展开更多
The present work dealt with the preconcentration of rare earth elements in Saghand ore(Yazd province,Iran)which was achieved by Humphrey spiral using orthogonal optimization method after scrubbing the sample at 45%sol...The present work dealt with the preconcentration of rare earth elements in Saghand ore(Yazd province,Iran)which was achieved by Humphrey spiral using orthogonal optimization method after scrubbing the sample at 45%solid pulp density for 30 min.The pulp was diluted and was fed to a Humphrey spiral for upgrading.The process parameters considered were feed size,feed solids and feed rate,and Taguchi’s L9(34)orthogonal array(OA)was selected for optimization of the process.The results show that the feed rate and feed size were more significant than the other operation parameters of the process.It was also found that under optimal conditions,the concentrate grade of rare earth elements increased from2860 10 6to 6050 10 6and recovery reached to 58%.展开更多
A simple and economical chemical process for obtaining high purity neodymium oxide is discussed. The raw material in the form of RE （rare earth） carbonates is produced industrially in Brazil from monazite. Using thi...A simple and economical chemical process for obtaining high purity neodymium oxide is discussed. The raw material in the form of RE （rare earth） carbonates is produced industrially in Brazil from monazite. Using this concentrate as the feed material, ion exchange with a strong cationic resin, commonly used for water treatment, and without the use of retention ions was used for the fractionating of the REE （rare earth elements）. The eluent was ammonium salt of EDTA （ethylenediaminetetraacetic acid） at pH 4.0. The complex of EDTA-neodymium was transformed into neodymium oxides via oxalate precipitation. We produced 99.9% pure Nd203 in yields greater than or equal to 80%. Molecular absorption spectrophotometry was used to monitor the neodymium content during the process and sector field inductively coupled plasma mass spectrometry was used to certify the purity of the neodymium oxides. The typical neodymium oxides obtained contained the followings contaminants in micrograms per gram： Sc （4.09）; Y （0.39）; La （0.78）; Ce （5.62）; Pr （4.56）; Sm （11.10）; Eu （1.10）; Gd （14.30）; Tb （29.3）; Dy （4.15）; Ho （8.39）; Er （13.80）; Tm （0.23）; Yb （2.29）; Lu （0.39）. High purity neodymium oxides obtained from this procedure replaced the imported product used in research and development work on rare earth at IPEN/CNEN-SP （Instituto de Pesquisas Energeticas e Nucleares/Comissfio Nacional de Eneergia Nuclear-Sao Paulo）.展开更多
Objective To generate and characterize anti-idiotypic monoclonal antibody (Ab2) that bears the internal image of nasopharyngeal carcinoma (NPC) associated antigen. Methods Using NPC monoclonal antibody (Ab1) as immu...Objective To generate and characterize anti-idiotypic monoclonal antibody (Ab2) that bears the internal image of nasopharyngeal carcinoma (NPC) associated antigen. Methods Using NPC monoclonal antibody (Ab1) as immunogen, hybridoma cells were obtained by fusion of SP2/0 myeloma cells with immunized murine spleen cells. Positive clones were screened by Sandwich ELISA and a binding inhibition test. To determine whether Ab2 possess the internal image of the original antigen or not, mice were immunized with Ab2. ELISA and the competitive inhibition assay tested anti-anti-idiotypic antibodies (Ab3) in anti-sera. Cell-mediated immunity to tumors induced by Ab2 was investigated by a delayed-type hypersensitivity response and the mouse T-cell proliferation assay. Results Anti-idiotypic monoclonal antibodies against the monoclonal anti-NPC antibodies FC2 and HNL5 were generated that recognize NPC associated antigens. These Ab2, which were designated 2H4 and 5D3, could inhibit the binding of FC2 or HNL5 to NPC cell lines. Anti-sera from the immunized mice, which contained Ab3, could compete with FC2 or HNL5 for binding with NPC cell by a competitive inhibition assay. Mice immunized with 2H4 or 5D3 coupled with keyhole limpet hemocyanin (KLH), showed a positive and specific delayed-type hypersensitivity (DTH) reaction after stimulation by NPC cells. The mouse T cell proliferative assay indicated that there was a significantly higher proliferative response of the splenocytes in the experimental groups than that in control groups. Conclusions Anti-idiotypic antibodies 2H4 and 5D3 are Ab2 beta bearing the internal image of the epitope of NPC associated antigen. Either 2H4 or 5D3 expressing three-dimensional shapes that resemble the structure of natural antigens could induce humoral and cellular immune response.展开更多
Biological world always provides inspirations for engineering designs, and insects are important targets to mimic. For the Coleoptera, its flight has been emphasized for long. However, the invisible folding procedure ...Biological world always provides inspirations for engineering designs, and insects are important targets to mimic. For the Coleoptera, its flight has been emphasized for long. However, the invisible folding procedure of hind wings, which occurs under the stiff elytra after flight, still remains unknown. In this paper, the wing folding process and the surficial microstructures of elytra, hind wing and abdomen are investigated by video recording and scanning electron microscopy. The results show that there are hooklike protrusions approximately 15 μm in length distributing on the inner side of elytra, and bump-like protrusions on the hind wings. The ＇hooks＇ may anchor the ＇bumps＇ on the main wing to prevent corrugation during folding. The horizontal protrusions observed on the abdomen shape a hairy cuticle, which is conducive to a better wing-abdomen interaction. Thus, the ratcheting mechanism that wing folding facilitated by micro-protrusions on the body surface is revealed. This new finding helps us to further understand the functions of diversely shaped protrusions in the physiology of insects. More importantly, the ratcheting mechanism could serve as a cuticle interaction model and inspire new engineering applications, such as microsystems.展开更多
文摘Glyptosternoid fishes are a group of sisorid catfishes living in torrents of rivers mainly originating from the Qinghai-Tibet Plateau. Based on our survey in the Drung River Basin, seven collecting sites were investigated and 271 glyptosternoid fishes caught belong to three species （Pareuchiloglanis kamengensis, Exostoma labiatum and Oreoglanis mocropterus）. Features of the distribution of the three catfishes were assessed. More individuals of E. labiatum were caught in the lower reaches of the Drung River with fast water velocity and it might be more adapted to a torrent habitat. The relationships between standard length （L） and weight （W） for P. kamengensis, E. labiatum and O. macropterus were also studied, and the parameter b of the L-W relationship （W = aL^b） ranged between 2. 8201 and 3. 0131. From the present study, all the three catfish species grow allometrically and the growth type of E. labiatum is the closest to a symmetrical one.
基金the deputy director of Research and Development in Atomic Energy of Iran for financial support as well as Nuclear Science and Technology Research Institute for technical support
文摘The present work dealt with the preconcentration of rare earth elements in Saghand ore(Yazd province,Iran)which was achieved by Humphrey spiral using orthogonal optimization method after scrubbing the sample at 45%solid pulp density for 30 min.The pulp was diluted and was fed to a Humphrey spiral for upgrading.The process parameters considered were feed size,feed solids and feed rate,and Taguchi’s L9(34)orthogonal array(OA)was selected for optimization of the process.The results show that the feed rate and feed size were more significant than the other operation parameters of the process.It was also found that under optimal conditions,the concentrate grade of rare earth elements increased from2860 10 6to 6050 10 6and recovery reached to 58%.
文摘A simple and economical chemical process for obtaining high purity neodymium oxide is discussed. The raw material in the form of RE （rare earth） carbonates is produced industrially in Brazil from monazite. Using this concentrate as the feed material, ion exchange with a strong cationic resin, commonly used for water treatment, and without the use of retention ions was used for the fractionating of the REE （rare earth elements）. The eluent was ammonium salt of EDTA （ethylenediaminetetraacetic acid） at pH 4.0. The complex of EDTA-neodymium was transformed into neodymium oxides via oxalate precipitation. We produced 99.9% pure Nd203 in yields greater than or equal to 80%. Molecular absorption spectrophotometry was used to monitor the neodymium content during the process and sector field inductively coupled plasma mass spectrometry was used to certify the purity of the neodymium oxides. The typical neodymium oxides obtained contained the followings contaminants in micrograms per gram： Sc （4.09）; Y （0.39）; La （0.78）; Ce （5.62）; Pr （4.56）; Sm （11.10）; Eu （1.10）; Gd （14.30）; Tb （29.3）; Dy （4.15）; Ho （8.39）; Er （13.80）; Tm （0.23）; Yb （2.29）; Lu （0.39）. High purity neodymium oxides obtained from this procedure replaced the imported product used in research and development work on rare earth at IPEN/CNEN-SP （Instituto de Pesquisas Energeticas e Nucleares/Comissfio Nacional de Eneergia Nuclear-Sao Paulo）.
基金ThisinvestigationwassupportedbygrantsfromtheNationalNaturalScienceFoundationofChina (No 392 70 716 )ChinaMedicalBoardinNewYork (No 90 5 2 9project 7)
文摘Objective To generate and characterize anti-idiotypic monoclonal antibody (Ab2) that bears the internal image of nasopharyngeal carcinoma (NPC) associated antigen. Methods Using NPC monoclonal antibody (Ab1) as immunogen, hybridoma cells were obtained by fusion of SP2/0 myeloma cells with immunized murine spleen cells. Positive clones were screened by Sandwich ELISA and a binding inhibition test. To determine whether Ab2 possess the internal image of the original antigen or not, mice were immunized with Ab2. ELISA and the competitive inhibition assay tested anti-anti-idiotypic antibodies (Ab3) in anti-sera. Cell-mediated immunity to tumors induced by Ab2 was investigated by a delayed-type hypersensitivity response and the mouse T-cell proliferation assay. Results Anti-idiotypic monoclonal antibodies against the monoclonal anti-NPC antibodies FC2 and HNL5 were generated that recognize NPC associated antigens. These Ab2, which were designated 2H4 and 5D3, could inhibit the binding of FC2 or HNL5 to NPC cell lines. Anti-sera from the immunized mice, which contained Ab3, could compete with FC2 or HNL5 for binding with NPC cell by a competitive inhibition assay. Mice immunized with 2H4 or 5D3 coupled with keyhole limpet hemocyanin (KLH), showed a positive and specific delayed-type hypersensitivity (DTH) reaction after stimulation by NPC cells. The mouse T cell proliferative assay indicated that there was a significantly higher proliferative response of the splenocytes in the experimental groups than that in control groups. Conclusions Anti-idiotypic antibodies 2H4 and 5D3 are Ab2 beta bearing the internal image of the epitope of NPC associated antigen. Either 2H4 or 5D3 expressing three-dimensional shapes that resemble the structure of natural antigens could induce humoral and cellular immune response.
基金supported by the National Natural Science Foundation of China(51176087)
文摘Biological world always provides inspirations for engineering designs, and insects are important targets to mimic. For the Coleoptera, its flight has been emphasized for long. However, the invisible folding procedure of hind wings, which occurs under the stiff elytra after flight, still remains unknown. In this paper, the wing folding process and the surficial microstructures of elytra, hind wing and abdomen are investigated by video recording and scanning electron microscopy. The results show that there are hooklike protrusions approximately 15 μm in length distributing on the inner side of elytra, and bump-like protrusions on the hind wings. The ＇hooks＇ may anchor the ＇bumps＇ on the main wing to prevent corrugation during folding. The horizontal protrusions observed on the abdomen shape a hairy cuticle, which is conducive to a better wing-abdomen interaction. Thus, the ratcheting mechanism that wing folding facilitated by micro-protrusions on the body surface is revealed. This new finding helps us to further understand the functions of diversely shaped protrusions in the physiology of insects. More importantly, the ratcheting mechanism could serve as a cuticle interaction model and inspire new engineering applications, such as microsystems.
