Microstructure Evolution and Recrystallization Mechanisms of a Cu-Cr-Sn Alloy during Thermal Deformation Process.

Thermal deformation behavior of Cu-Cr-Sn alloy ingots under deformation temperatures ranging from 600 °C to 950 °C and strain rates from 0.01 s-1 to 10 s-1 was investigated in detail. The thermal deformation constitutive equation and thermal processing map of the alloy were established, respectively. The activation energy Q was determined as 430.61 KJ/mol. The optimal deformation system corresponding to the hot working diagram was a deformation temperature of 900 °C and strain rate of 0.1 s-1. Under these deformation conditions, twin dynamic recrystallization (TDRX), continuous dynamic recrystallization (CDRX), and discontinuous dynamic recrystallization (DDRX) occurred simultaneously, with the twinning process causing the stress-strain curve to exhibit a wavy change. The thermal deformation microstructure of the alloy is co-regulated by different recrystallization mechanisms, with DDRX occurring mainly at low deformation temperatures, and both CDRX and DDRX occurring at high deformation temperatures.

Efficient nitrogen removal by multi-stage A/O mud membrane composite process with segmented influent: Performance and microbial community structure.

In this paper, a multi-stage A/O mud membrane composite process with segmented influent was constructed for the first time and compared with the traditional activated sludge process and the multi-stage A/O pure membrane process with segmented influent. The nitrogen removal efficiency of the process under different influencing factors was studied. Under the optimum conditions, the highest removal rate of ammonia nitrogen can reach 99%, and the average removal rate of total nitrogen was 80%. The removal rate of COD in effluent reached 93%. The relative abundance of Proteobacteria was the highest in the multi-stage A/O mud membrane composite reactor with segmented influent. The community diversity and richness of activated sludge and biofilm in aerobic pool were the highest. Dechloromonas, Flavobacterium and Rhodobacter were dominant bacteria, and they were aerobic denitrifying bacteria that significantly contributed to the removal rate of ammonia nitrogen.

Incorporation of Nasutitermes takasagoensis endoglucanase into cell surface-displayed minicellulosomes in Pichia pastoris X33.

In this study, the yeast Pichia pastoris was genetically modified to assemble minicellulosomes on its cell surface by the heterologous expression of a truncated scaffoldin CipA from Clostridium acetobutylicum. Fluorescence microscopy and western blot analysis confirmed that CipA was targeted to the yeast cell surface and that NtEGD, the Nasutitermes takasagoensis endoglucanase that was fused with dockerin, interacted with CipA on the yeast cell surface, suggesting that the cohesin and dockerin domains and cellulose-binding module of C. acetobutylicum were functional in the yeasts. The enzymatic activities of the cellulases in the minicellulosomes that were displayed on the yeast cell surfaces increased dramatically following interaction with the cohesin-dockerin domains. Additionally, the hydrolysis efficiencies of NtEGD for carboxymethyl cellulose, microcrystal cellulose, and filter paper increased up to 1.4-fold, 2.0-fold, and 3.2-fold, respectively. To the best of our knowledge, this is the first report describing the expression of C. acetobutylicum minicellulosomes in yeast and the incorporation of animal cellulases into cellulosomes. This strategy of heterologous cellulase incorporation lends novel insight into the process of cellulosome assembly. Potentially, the surface display of cellulosomes, such as that reported in this study, may be utilized in the engineering of S. cerevisiae for ethanol production from cellulose and additional future applications.

Evolutionary comparisons of miRNA regulation system in six model organisms.

miRNAs are a class of endogenous small non-coding regulatory RNAs, that can mediate the transcriptional gene silencing as well as gene expression activation. miRNAs, which are found in a wide range of species, participate in cell differentiation, proliferation, development, apoptosis, tumorigenesis, metabolism, immune system, and signaling pathways. Here, we focused on the relationship between evolution and the miRNA system, with an emphasis on both miRNAs and their target genes. Six species from the evolutionary ladder were selected as a focus of this study. Public data were retrieved and combined to compare miRNAs abundance, miRNA families, molecular functions of target genes, biological processes of target genes, protein families of target gene products, transcription factors regulated by the miRNAs, signaling pathways and tissues across the six species. We found that the expansion rate of miRNAs was significantly higher compared to other genes in human evolution. Newborn miRNA families, which were quantitatively larger than dead miRNA families, seem to be closely related to the species complexity and tissue specificity. Additionally, miRNAs in higher order species were more likely to target genes related to signaling and the immune system, while miRNAs from lower order species preferred to target genes related to the embryonic development process, reproduction and growth. Meanwhile, miRNA systems displayed diversity in regulating transcription factors, signaling pathways and tissues. Our research suggested that the miRNA system might promote evolution, especially in higher species.

(Cinnamato-κ(2)O,O')(5,5,7,12,12,14-hexa-methyl-1,4,8,11-tetra-aza-cyclo-tetra-decane-κ(4)N,N',N'',N''')nickel(II) perchlorate monohydrate.

In the title compound, [Ni(C(9)H(7)O(2))(C(16)H(36)N(4))]ClO(4)·H(2)O, the macrocyclic 5,5,7,12,12,14-hexa-methyl-1,4,8,11-tetra-aza-cyclo-tetra-decane ligand (L) folds around the Ni(II) atom, which is also chelated by the carboxyl-ate group. The geometry is a distorted N(4)O(2) octa-hedron. In the crystal, adjacent mol-ecules are connected by O-H⋯O and N-H⋯O hydrogen bonds into a zigzag chain parallel to [010].

Assessment of the role of brine shrimp Artemia in white spot syndrome virus (WSSV) transmission.

Challenge tests with Artemia four different development stages (nauplii, metanauplii, pseudoadults and adults) to white spot syndrome virus was carried out by immersion challenge and virus-phytoplankton adhesion route in order to asses the possibility of Artemia acting as a vector of WSSV to penaeid shrimp Litopenaeus vannamei postlarvae. The WSSV succeeded in infecting four stages Artemia, and nested-PCR detection for WSSV revealed positive results to virus-phytoplankton adhesion route. No mass mortalities were observed in penaeid shrimp postlarvae fed with WSSV-positive Artemia which exposed to WSSV by virus-phytoplankton adhesion route, whereas WSSV DNA detected in penaeid shrimp postlarvae by nested-PCR. By contrary, no WSSV-positive was detected in any animal fed with WSSV-negative Artemia. These results indicated that Artemia could serve as a vector in WSSV transmission.

[Establishment and application of a loop-mediated isothermal amplification method for rapid diagnosis of Vibrio cholerae].

OBJECTIVE: To establish a loop-mediated isothermal amplification (LAMP) method for rapid diagnosis of Vibrio cholerae. METHODS: Based on the ompW nucleic sequence of Vibrio cholerae, a pair of primers was designed for LAMP. The reaction conditions were optimized, and the specificity, sensitivity, and practicability of LAMP were tested using 47 bacterial strains and simulated contaminated sites. RESULTS: The results of viable bacterium count showed that LAMP was capable of detecting Vibrio cholerae at a level as low as 1.6x10(2) cfu/ml. The minimal detectable concentration was 1.6+10(3) cfu/ml for simulated contaminated samples such as feces and seawater, and 1.6+10(4) cfu/ml for contaminated milk. All the 21 strains of Vibrio cholerae yielded positive results in LAMP, and the 26 strains of other bacteria all showed negative results, with a detection specificity of 100%. CONCLUSION: The established LAMP method has high specificity and sensitivity for detecting Vibrio cholerae and is applicable in field monitoring and epidemiological study of Vibrio cholerae.

[The value of loop-mediated isothermal amplification method for rapid diagnosis of EBV DNA].

OBJECTIVE: To establish a rapid method for EBV detection with loop-mediated isothermal amplification (LAMP), and to make it as a clue for early diagnosis of nasopharyngeal carcinoma cancer. METHOD: EBV DNA was fast extracted from samples after boiling, while the whole detection will be finished within an hour with specific amplification of EBV gene by LAMP. RESULT: High specificity was shown from EBV detection of 33 clinical samples. Comparing with PCR, LAMP is more simple and convenient to perform under isothermal conditions, and require no special apparatus, thus, it is more economical and practical. CONCLUSION: LAMP analysis of EBV may be an efficient and easy way for clinical diagnosis of nasopharyngeal carcinoma.

BLogo: a tool for visualization of bias in biological sequences.

UNLABELLED: Blogo is a web-based tool that detects and displays statistically significant position-specific sequence bias with reduced background noise. The over-represented and under-represented symbols in a particular position are shown above and below the zero line. When the sequences are in open reading frames, the background frequency of nucleotides could be calculated separately for the three positions of a codon, thus greatly reducing the background noise. The chi(2)-test or Fisher's exact test is used to evaluate the statistical significance of every symbol in every position and only those that are significant are highlighted in the resulting logo. The perl source code of the program is freely available and can be run locally. AVAILABILITY: http://acephpx.cropdb.org/blogo/, http://www.bioinformatics.org/blogo/.

Polymorphic amino acids at codons 9 and 37 of HLA-DQB1 alleles may confer susceptibility to cervical cancer among Chinese women.

Cervical cancer is strongly associated with the infection by oncogenic forms of human papillomavirus (HPV). Although most women are able to clear HPV infection, some develop persistent infections that may lead to cancer, implying genetic susceptibility factors for malignant progression. To verify whether HLA class II DQB1 polymorphism is related to cervical cancer in Chinese population, HLA-DQB typing was carried out by PCR-SBT for 258 patients with cervical cancer and 284 healthy controls, and the allele frequencies were calculated. In this study, HLA-DQB1*060101 and DQB1*0602 alleles were significantly higher in the HPV16 infected patients with cervical cancer compared with healthy controls (chi(2) = 31.7452, p < 0.0001; chi(2) = 12.7838, p(c) = 0.0066), but DQB1*050201 allele was significantly lower (chi(2) = 26.2187, p < 0.0001). This result indicates that HLA-DQB1*060101 and DQB1*0602 may confer susceptibility to cervical cancer, and DQB1*050201 may contribute to the resistance to the development of cervical cancer among Chinese women. Sequence analysis reveals that DQB1*060101 allele encodes Leu at position 9 and Asp at position 37, unique to the susceptibility to cervical cancer, whereas the other DQB1 alleles encode Phe or Tyr and Ile or Tyr at the same two positions, respectively. This finding implies that polymorphic amino acids at the putative antigen binding residues 9 and 37 of HLA-DQB1 alleles may play an important role in the development of cervical cancer.