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Because of the low recovery of -10 μm fine scheelite particles in scheelite flotation, some amount of fine scheelite is lost in the tailing, resulting in the wasting of scheelite resources. It is urgently needed to solve the problems inherent in fine scheelite flotation and explore new processes of fine ores to effectively recover fine scheelite. The carrier flotation has proven to be an effective method of improving the recovery of scheelite by promoting the recovery of fine particles. Based on studies of the effect of particle size and particle fraction on scheelite flotation, the application of auto-carrier flotation in the recovery of -10 μm scheelite using sodium carbonate in both the presence and absence of sodium carbonate were studied. The effect of percentage carrier, particle size of carrier, and sodium carbonate on the auto-carrier flotation of scheelite were also studied through flotation tests, theoretical calculation, and instrument testing. The results indicate that the contents and particle size of coarse particles exert significant influence on auto-carrier flotation. The recovery of fine scheelite with a size of -10 μm is increased by using auto-carrier flotation with the proper carrier percentage and size. The addition of sodium carbonate strengthens the carrier flotation of scheelite and therefore improves the scheelite recovery. Furthermore, the addition of sodium carbonate can also expand the percentage and particle size range of carrier mineral. The results of mechanism studies indicate that there exists interaction among scheelite particles, which results in the adhesion of fine particle to carrier. The hydrophobic force is the main reason that the scheelite particles attracted each other, and the addition of sodium carbonate increases the adsorption of sodium oleate onto the scheelite surface, thereby improving the hydrophobicity of scheelite and the hydrophobic force among scheelite particles. It can be concluded that the auto-carrier flotation of scheelite can be improved by adding sodium carbonate.

The unsymmetric finite element is based on the virtual work principle with different sets of test and trial functions. In this article, the incompatible four‐node quadrilateral element and eight‐node hexahedral element originated by Wilson et al. are extended to their unsymmetric forms. The isoparametric shape functions together with Wilson's incompatible functions are chosen as the test functions, while internal nodes at the middle of element sides/edges are added to generate the trial functions with quadratic completeness in the Cartesian coordinate system. A local area/volume coordinate frame is established so that the trial shape functions can be explicitly obtained. The key idea which avoids the matrix inversion is that the trial nodal shape functions are constructed by standard quadratic triangular/tetrahedral elements and then transformed in consistent with the quadrilateral/hexahedral elements. Numerical examples show that the present elements keep the merits of both incompatible and unsymmetric elements, that is, high numerical accuracy, insensitivity to mesh distortion, free of trapezoidal and volumetric locking, and easy implementation. [ABSTRACT FROM AUTHOR]

Objective: To investigate the effects of autophagy activator (rapamycin, RAPA) and autophagy inhibitor (hydroxychloroquine, HCQ and 3-methyl adenine, 3-MA) on the proliferation, apoptosis and autophagy of multiple myeloma cell line of RPMI8226., Methods: RPMI8226 cells were treated with autophagy regulating drugs of different concentrations. The proliferation and apoptosis of cells were determined by CCK-8 and flow cytometry, respectively. The expressions of apoptosis-related proteins BCL-2, caspase-3 and PARP protein were assessed by Western blot. Autophagy was detected by monodansylcadaverine staining. Autophagic protein (LC-3b) and apoptosis-related proteins (caspase-3, PARP and BCL-2) were analyzed by Western blot., Results: RAPA and HCQ inhibited the proliferation of RPMI8226 in a concentration- and time-dependent manner, and increased the apoptosis. However, 3-MA did not show significantly inhibitory effect on the proliferation and apoptosis of RPMI8226. MDC staining showed that the more autophagic vacuoles could be detected in the higher concentration of RAPA, but the less autophagic vacuoles in the higher concentration of HCQ and 3-MA. Western blot showed that RAPA increased the expression of LC3-II/LC3-I, caspase-3 and PARP, but inhibited the expression of BCL-2. HCQ inhibited the expression of LC3-II/LC3-I and BCL-2, but increased the expression of caspase-3 and PARP. 3-MA inhibited the expression of LC3-II/LC3-I, but had no effect on the expression of caspase-3, PARP or BCL-2., Conclusion: Rapamycin can inhibit the proliferation, induce apoptosis and autophagy of RPMI 8226, the hydroxychloroquine can inhibit autophagy and proliferation of RPMI 8226, and induce apoptosis, the 3-MA can inhibit autophagy of RPMI 8226, but hardly has any effects on proliferation and apoptosis of RPMI 8226 cells.

The genetic polymorphisms of four microsatellite loci BM143, OarHH35, OarAE101, and BMS2508 were analyzed in 286 sheep of seven sheep populations (Small Tail Han sheep, Hu sheep, Ujumqin sheep, Suffolk sheep, Dorset sheep, Charolais sheep, F1 of Dorset male x Small Tail Han female sheep). The numbers of alleles for BM143, OarHH35, OarAE101, and BMS2508 are 9, 11, 14 and 9 in seven sheep populations, respectively. The polymorphism information content/number of effective alleles/ heterozygosity of BM143, OarHH35, OarAE101 and BMS2508 were 0.7073/3.7231/0.7314, 0.8267/6.4399/0.8447, 0.5743/2.5178/0.6028, 0.6172/3.0712/0.6744 in 286 sheep, respectively. The results revealed the greatest genetic variation at OarHH35 locus and the lowest at OarAE101, the greatest genetic variation in Small Tail Han sheep and the lowest in Hu sheep among seven sheep populations. In the unweighted pair group method with arithmetic mean (UPGMA) dendrograms based on Nei's D(A) distance and Nei's D(S) standard genetic distance, the Chinese native breeds (Small Tail Han sheep, Ujumqin sheep, Hu sheep) were grouped together, then with Charolais sheep. The F1 crossbred sheep, and the two British native sheep (Suffolk sheep, Dorset sheep) also clustered together. Microsatellite genotyping in sheep provided a useful tool for examining the genetic relationships among breeds (populations).

Small Tail Han sheep is an excellent local sheep breed in China. Small Tail Han sheep had significant characteristics of high prolificacy. The lambing percentage averaged 260 percent in Small Tail Han sheep. The polymorphisms of 5 microsatellite loci OarAE101, BM1329, BMS2508, TGLA54 and TGLA68 which were closely linked to the fecundity genes FecB and FecXI in sheep were detected in 244 ewes of Small Tail Han sheep. The PCR amplified products of microsatellites were detected by non-denatured (natural) polyacry lamide gel electrophoresis. Allele frequency, polymorphism information content, gene homogeneity and heterozygosity for 5 microsatellite loci were calculated. The number of alleles for BM1329, OarAE101, TGLA54, TGLA68 and BMS2508 were 6, 9, 5, 2 and 6 in Small Tail Han sheep, respectively. The range of allele sizes for BM1329, OarAE101, TGLA54, TGLA68 and BMS2508 were 160 bp to 180 bp, 97 bp to 135 bp, 116 bp to 136 bp, 98 bp to 100 bp, and 93 bp to 115 bp, respectively. The alleles of the greatest frequency for BM1329, OarAE101, TGLA54 and BMS2508 were 164 bp, 97 bp, 134 bp and 99 bp, respectively. Polymorphism information content/gene homogeneity/heterozygosity for BM1329, OarAE101, TGLA54, TGLA68 and BMS2508 were 0.4481/0.4840/0.5160, 0.3516/0.6375/0.3625, 0.2528/0.7326/0.2674, 0.3733/0.5034/0.4966 and 0.5809/0.3581/0.6419 in Small Tail Han sheep, respectively. The results revealed the greatest genetic variation in BMS2508 and the lowest in TGLA54. These results could provide, basic molecular data for the research on the germplasm characteristics of Small Tail Han sheep.

Small Tail Han sheep is an excellent local sheep breed in China. Small Tail Han sheep has significant characteristics of high prolificacy. The lambing percentage averaged 260 percent in Small Tail Han sheep. The genetic detection of 4 microsatellite loci OarAE101, OarHH35, BM143 and BMS2508 which were closely linked to the fecundity gene FecB in Booroola sheep was conducted in 159 sheep in Small Tail Han sheep, Dorset sheep, F1 hybzids(Dorset x Small Tail Han sheep). The results confirmed the genetic characteristics of codominance of microsatellite DNA. The PCR amplified products of microsatellites were detected by non-denatured (natural) polyacrylamide gel electrophoresis. The sequences of PCR amplification fragment of 6 clones of 4 microsatellite loci in Small Tail Han sheep were accepted by GenBank of National Center for Biotechnology Information, National Institutes of Health in USA, the GenBank accession numbers were AF394445, AF394446, AF394447, AF394448, AF394449, AF394450, respectively. The sequence homogeneity between OarAE101 in Small Tail Han sheep in this study and the ovine OarAE101 in GenBank was 98 percent. The sequence homogeneity between OarHH35 in Small Tail Han sheep in this study and the ovine OarHH35 in GenBank was 99 percent. The sequence homogeneity between BM143 in Small Tail Han sheep in this study and the bovine BM143 in GenBank was 95 percent. The sequence homogeneity between BMS2508 in Small Tail Han sheep in this study and the bovine BMS2508 in GenBank was 95 percent. OarAE101, OarHH35, BM143 and BMS2508 in Small Tail Han sheep were all perfect microsatellites. These results could provide molecular basic data for the research on the germplasm characteristics of Small Tail Han sheep.