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In this paper, a novel radial segmental blank holder technique based on electro-permanent magnet (EPM) technology is proposed. The blank holding force (BHF) can be independently and effectively applied on different regions of flange in a more convenient and low-energy way. The principles and advantages of radial segmental blank holder technique are first expatiated and analyzed by theoretical derivation and numerical simulation. The results indicate that there is no overheating problem during the continuous forming process. The distribution of the BHF applied by the radial segmental blank holder is more reasonable than from that of using the single blank holder and it can also better suppress wrinkling. Finally, the effectiveness of the EPM radial segmental blank holder is proven by forming experiments of 08Al steel. It is demonstrated that the flange wrinkling of the drawn cup is better eliminated using the new blank holder and the forming limit is improved compared to using the single blank holder.

Additional file 2: Table S1. The sequences information of fecal samples. Group: Normal, Model, SNT and Meto represent normal group, model group, Sini Decoction treatment group and metoprolol treatment group, respectively; Seq num: sequences number; Base num: number of bases.

The fluid-elastic instability is probably to occur in both transverse and streamwise directions. The studies of streamwise instability are mainly performed with the tubes are fixed in the transverse direction, which may not happen in the practical tube bundles. In this study, the effect of asymmetry of the tube stiffness on the streamwise instability was investigated through water tunnel tests and numerical simulations. The vibration was controlled by changing the stuffiness of tubes in the two directions. The results show that the streamwise vibration can affect instability threshold in the transverse direction in single tube tests, and the streamwise vibration was suppressed when the tubes fall into instability in transverse direction. The asymmetry of the tube stiffness can have an effect on streamwise and transverse instability, but the effect is not pronounced in the multi-flexible tube array.

A new blank holder divided into double rings is proposed, in which the blank holder force (BHF) can be independently and effectively applied on different flange regions. In this paper, the principle and characteristics of the new blank holder technique are expatiated by theoretical derivation and stress analysis. All results indicate that the distribution of BHF applied by the double rings blank holder is more reasonable than a single blank holder under the condition of proper parameter selection, and the wrinkling can be better suppressed. The effectiveness of the double rings blank holder has been proven by deep drawing experiments. Using the new blank holder technique, the flange wrinkling was demonstrated to be more eliminated than that using the single blank holder. Moreover, experimental results also corroborate that the parameters of BHF distribution ratio and the boundary diameter of the two rings have a great influence on the effects of the new blank holder technique.

Gametocyte proteins of Eimeria spp. are essential components of the oocyst wall, and some of these proteins have been analysed to identify targets of transmission-blocking vaccines against avian coccidiosis. In the present study, a cDNA from E. necatrix gametocytes was cloned and sequenced. The cDNA is 1473 bp in length and encodes a 490-amino-acid protein containing a tyrosine-serine (Tyr/Ser)-rich domain and a proline-methionine (Pro/Met)-rich domain. A quantitative real-time PCR (qPCR) analysis showed that the cDNA is expressed only during gametogenesis. A fragment containing the Tyr/Ser-rich domain (rEnGAM59) was expressed in Escherichia coli BL21 (DE3) cells. Immunoblotting showed that rEnGAM59 was recognized by the serum of convalescent chickens after infection with E. necatrix, and that an anti-rEnGAM59 antibody recognized a ∼59 kDa protein and two other proteins (∼35 kDa and ∼33 kDa) in gametocyte extracts. An immunofluorescence assay showed that the anti-rEnGAM59 antibody recognized wall-forming bodies in the macrogametocytes and oocyst walls. An in vivo vaccination and challenge trial was conducted to test the potential utility of rEnGAM59 as a vaccine. Immunized chickens performed better than the unimmunized and challenged (positive control) chickens. The intestinal lesion scores were significantly lower in the immunized groups than in the positive control group (P0.05). In contrast, the body weight gains (BWG) were significantly higher in the immunized groups than in the positive control group (P0.05). There were no significant differences in the lesion scores and BWG between the groups immunized with rEnGAM59 protein or with live oocysts (P0.05). Chickens immunized with rEnGAM59 protein had a significantly higher antigen-specific serum IgY response (P0.05). rEnGAM59 protein can be used as candidate antigen to develop a recombinant coccidiosis vaccine.

Industrial development and human activities have greatly altered land cover over the past several decades. To measure net primary production (NPP) is a way to understand the photosynthesis capabilities of the vegetation. Great progress was made in the study of zonal NPP estimation, especially in world wide or in China; however, quantitative research on NPP at the regional scale using multi-temporal satellite data is still inadequate. In this study, Wuhan city of Hubei Province, China, was chosen as the study area.17 scenes of Land sat images were used to estimate annual NPP of 1988 and 2002 using photosynthesis curve model with vegetation index based on universal pattern decomposition method (VIUPD). NPP of Wuhan area in 1988 was estimated to be 2.64times10-3PgC/a, and average NPP was 356.76gC/m2/a; where NPP in 2002 was estimated as 2.52times10-3PgC/a, and average NPP was 341.17 gC/m2/a. Although NPP of China increases 0.6973 PgC from 1982 to 2000 with the speed of 0.0367 PgC per year, NPP of Wuhan decreased. It was found because of speeding up urbanization of Wuhan for these twenty years by spatial-temporal patterns analysis.

Background It is well known that different Eimeria maxima strains exhibit significant antigenic variation. However, the genetic basis of these phenotypes remains unclear. Methods Total RNA and mRNA were isolated from unsporulated oocysts of E. maxima strains SH and NT, which were found to have significant differences in immunogenicity in our previous research. Two subtractive cDNA libraries were constructed using suppression subtractive hybridization (SSH) and specific genes were further analyzed by dot-blot hybridization and qRT-PCR analysis. Results A total of 561 clones were selected from both cDNA libraries and the length of the inserted fragments was 0.25–1.0 kb. Dot-blot hybridization revealed a total of 86 differentially expressed clones (63 from strain SH and 23 from strain NT). Nucleotide sequencing analysis of these clones revealed ten specific contigs (six from strain SH and four from strain NT). Further analysis found that six contigs from strain SH and three from strain NT shared significant identities with previously reported proteins, and one contig was presumed to be novel. The specific differentially expressed genes were finally verified by RT-PCR and qRT-PCR analyses. Conclusions The data presented here suggest that specific genes identified between the two strains may be important molecules in the immunogenicity of E. maxima that may present potential new drug targets or vaccine candidates for coccidiosis.