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This study was conducted to investigate the effects of traditional Chinese medicine compounds (TCMC) on rumen fermentation, methane emission and populations of ruminal microbes using an in vitro gas production technique. Cablin patchouli herb (CPH), Atractylodes rhizome (AR), Amur Cork-tree (AC) and Cypsum were mixed with the weight ratios of 1:1:1:0.5 and 1:1:1:1 to make up TCMC1 and TCMC2, respectively. Both TCMC were added at level of 25 g/kg of substrate dry matter. In vitro gas production was recorded and methane concentration was determined at 12 and 24 h of incubation. After 24 h, the incubation was terminated and the inoculants were measured for pH, ammonia nitrogen, volatile fatty acids (VFA). Total deoxyribonucleic acid of ruminal microbes was extracted from the inocula, and populations were determined by a real-time quantitative polymerase chain reaction. Populations of total rumen methanogens, protozoa, total fungi, Ruminococcus albus, Fibrobacter succinogenes and Ruminococcus flavefaciens were expressed as a proportion of total rumen bacterial 16S ribosomal deoxyribonucleic acid. Compared with the control, the 2 TCMC decreased (P ≤ 0.05) total VFA concentration, acetate molar proportion, acetate to propionate ratio, gas and methane productions at 12 and 24 h, hydrogen (H) produced and consumed, and methanogens and total fungi populations, while the 2 TCMC increased (P ≤ 0.05) propionate molar proportion. Traditional Chinese medicine compound 1 also decreased (P ≤ 0.05) R. flavefaciens population. From the present study, it is inferred that there is an effect of the TCMC in suppressing methanogenesis, probably mediated via indirect mode by channeling H2 utilized for methanogenesis to synthesis of propionate and direct action against the rumen microbes involved in methane formation. In addition, the relative methane reduction potential (RMRP) of TCMC2 was superior to that of TCMC1. Keywords: Traditional Chinese medicine compound, Fermentation characteristics, Methanogenesis, Ruminal microbes, In vitro

Lactate is formed by many species of colonic bacteria, and can accumulate to high levels in the colons of inflammatory bowel disease subjects. Conversely, in healthy colons lactate is metabolized by lactate-utilizing species to the short-chain fatty acids butyrate and propionate, which are beneficial for the host. Here, we investigated the impact of continuous lactate infusions (up to 20 mM) at two pH values (6.5 and 5.5) on human colonic microbiota responsiveness and metabolic outputs. At pH 5.5 in particular, lactate tended to accumulate in tandem with decreases in butyrate and propionate and with corresponding changes in microbial composition. Moreover, microbial communities with low numbers of lactate-utilizing bacteria were inherently less stable and therefore more prone to lactate-induced perturbations. These investigations provide clear evidence of the important role these lactate utilizers may play in health maintenance. These should therefore be considered as potential new therapeutic probiotics to combat microbiota perturbations., Lactate can be produced by many gut bacteria, but in adults its accumulation in the colon is often an indicator of microbiota perturbation. Using continuous culture anaerobic fermentor systems, we found that lactate concentrations remained low in communities of human colonic bacteria maintained at pH 6.5, even when dl-lactate was infused at 10 or 20 mM. In contrast, lower pH (5.5) led to periodic lactate accumulation following lactate infusion in three fecal microbial communities examined. Lactate accumulation was concomitant with greatly reduced butyrate and propionate production and major shifts in microbiota composition, with Bacteroidetes and anaerobic Firmicutes being replaced by Actinobacteria, lactobacilli, and Proteobacteria. Pure-culture experiments confirmed that Bacteroides and Firmicutes isolates were susceptible to growth inhibition by relevant concentrations of lactate and acetate, whereas the lactate-producer Bifidobacterium adolescentis was resistant. To investigate system behavior further, we used a mathematical model (microPop) based on 10 microbial functional groups. By incorporating differential growth inhibition, our model reproduced the chaotic behavior of the system, including the potential for lactate infusion both to promote and to rescue the perturbed system. The modeling revealed that system behavior is critically dependent on the proportion of the community able to convert lactate into butyrate or propionate. Communities with low numbers of lactate-utilizing bacteria are inherently less stable and more prone to lactate-induced perturbations. These findings can help us to understand the consequences of interindividual microbiota variation for dietary responses and microbiota changes associated with disease states. IMPORTANCE Lactate is formed by many species of colonic bacteria, and can accumulate to high levels in the colons of inflammatory bowel disease subjects. Conversely, in healthy colons lactate is metabolized by lactate-utilizing species to the short-chain fatty acids butyrate and propionate, which are beneficial for the host. Here, we investigated the impact of continuous lactate infusions (up to 20 mM) at two pH values (6.5 and 5.5) on human colonic microbiota responsiveness and metabolic outputs. At pH 5.5 in particular, lactate tended to accumulate in tandem with decreases in butyrate and propionate and with corresponding changes in microbial composition. Moreover, microbial communities with low numbers of lactate-utilizing bacteria were inherently less stable and therefore more prone to lactate-induced perturbations. These investigations provide clear evidence of the important role these lactate utilizers may play in health maintenance. These should therefore be considered as potential new therapeutic probiotics to combat microbiota perturbations.

This paper analyzed the feasibility of tailings briquetting for filling mining subsidence area based on the actual conditions. In the experiment, the diameter 25mm filling balls were made of slurry of Jinshandian tailings and cement, the cement tailing ratio was 1:4, the concentration of slurry was respectively 68%, 70%, 72%, 75%, and the falling strength, the compressive strength, the powder ratio about the filling balls were tested. The results showed that the falling strength was more than 50 times/A; the compressive strength was 5.23~21.12MPa; the powder ratio was 0.69%~10.52%. The results of the PFC2D numerical simulation showed that the maximum stress among the filling balls was 3.39MPa during the ore drawing process. The stress was lower than the minimum compressive strength of 5.23MPa, and the corresponding powder ratio was less than 8%. It has been concluded that the filling-body is able to meet the requirement of the strength and the powder ratio in the mine filling. The filling-body can be applied to backfilling subsidence area.

A new geometric correction method in processing close range digital photograph is presented. All the critical steps involved in the geometric correction method are briefed and discussed, including determination of Control Points (CP) on the exposure of the rock mass, projection of the 3-D CPs on the exposure of the rock mass to the projection plane, mathematically solving the transformation matrix, geometrically correcting and resampling the digital photograph. As an illustrative example, the whole process of application of the method for a specific digital photograph taken from an outcrop of rock mass is also presented. It is found that the new geometric correction method is effective and more convincing.

Fluoralkylpolysiloxane modified Polyurethane (FSPU) films with high water contact angle (CA) were prepared. fluoralkylpolysiloxane was obtained using perfluoro octyl sulfuryl fluoride and terminal amino-silicone oil as reactants. Then, the isocyanate end capped PU prepolymer was synthesized by reacting isocyanate with a soft segment mixed by active amino-end-capping fluoralkylpolysiloxane and polyether glycol. The fluoralkylpolysiloxane modified PU films were obtained after the PU prepolymer was cured by 3,3 '- dichloro -4,4' – amino - diphenyl methane (MOCA). The results showed that the modified polyurethane with 10% (mass fraction) PFATPS had a good compatibility, low surface energy, surface water contact angle and surface oil contact angle was improved by 49° and 37° respectively, and heat resistance, water resistance was apparently improved.

The proton-translocating vacuolar ATPase (V-ATPase) acidifies the endocytic network of eukaryotic cells. Although all eukaryotic cell types require low to moderate levels of V-ATPase, some proton-secreting cells express amplified levels for use in specialized membrane domains. To characterize genetic elements required for this heightened expression, we studied transcription and stability of mRNA encoding the V-ATPase c subunit in a low expressing fibroblast cell line (NIH 3T3) and a high expressing macrophage cell line (RAW 264.7). Isolation of the promoter and mapping of the transcriptional start site indicated that the c subunit promoter is TATA-less and initiates transcription at a single site. Promoter activity was regulated through the same transcription factor binding sites in both cell types, which showed no discernible difference in rates of c subunit transcription. In contrast, c subunit transcripts showed markedly greater stability in RAW cells than in 3T3 cells, as did other constitutively expressed V-ATPase subunit transcripts. Only the B and 'a' subunits, which are expressed in multiple isoforms, were not regulated solely by mRNA stability. These results suggest that overall expression levels of the V-ATPase are set primarily by regulation of mRNA stability and that transcriptional mechanisms determine subunit composition in varying cell types.

A fluoride-containing organic silane was synthesized by the reaction of N-ethyl-N-hydroxy-ethyl perfluorinated octyl sulfonamide (EHPOS), N-(β-aminoethyl)-γ-aminopropyl trimethoxy silane (ATS) and cis-butenedioic anhydride (CA). The experimental results show that the yield of product is up to 87% when the molar ratio of EHPOS: CA: ATS is 1: 1.05: 1.1. EHPOS and CA were maintained at 115 °C for 3 hours, then after cooling the reaction solution to 75 °C, ATS was added and reacted for another 3.5 hours at 145 °C. The structure of the product and thermal properties were characterized by Fourier transform infrared (FTIR) and thermogravimetric analysis (TGA), respectively. Results show that fluoride-containing organic silane has excellent thermal stability below 185 °C.

2-Cetyl-3-20 keto acid(N-ethyl perfluorinated octyl sulfonamide) N- ethyl ester was synthesized by the reaction of N-ethyl-N-hydroxyethyl perfluorinated octyl sulfonamide and alky ketene dimer. The experimental results show that the yield of products can be 89% when the molar ratio of perfluorinated octyl sulfonamide to ketene dimer is 1:1.1 and the reaction lasts about four hours at 80 °C. The structure of the product was characterized by FTIR and 1HNMR. The product can dissolve in polar solvents such as NMP, DMAC, THF, DMSO, CHCl3, and 10% weight-loss temperature measured by TGA is 202 °C.

Eight Caulobacter crescentus flagellar genes, flmA , flmB , flmC , flmD , flmE , flmF , flmG , and flmH , have been cloned and characterized. These eight genes are clustered in pairs ( flmAB , flmCD , flmEF , and flmGH ) that appear to be structurally organized as operons. Homology comparisons suggest that the proteins encoded by the flm genes may be involved in posttranslational modification of flagellins or proteins that interact with flagellin monomers prior to their assembly into a flagellar filament. Expression of the flmAB , flmEF , and flmGH operons was shown to occur primarily in predivisional cells. In contrast, the flmCD operon was expressed throughout the cell cycle, with only a twofold increase in predivisional cells. The expression of the three temporally regulated operons was subject to positive regulation by the CtrA response regulator protein. Mutations in class II and III flagellar genes had no significant effect on the expression of the flm genes. Furthermore, the flm genes did not affect the expression of class II or class III flagellar genes. However, mutations in the flm genes did result in reduced synthesis of the class IV flagellin proteins. Taken together, these data indicate that the flm operons belong to a new class of flagellar genes.

A gene, fdxP, was identified upstream of the rrnA gene in Caulobacter crescentus and shown to encode ferredoxin II (FdII) by insertional inactivation. FdII is homologous to a class of [2Fe-2S] ferredoxins typified by putidaredoxin. Furthermore, reconstitution assays demonstrated that FdII was able to promote p-hydroxybenzoate hydroxylase activity in ferredoxin-depleted extracts. Thus, biodegradation of p-hydroxybenzoate may be ferredoxin dependent in C. crescentus.

Directional pattern is a representation of original fingerprint image. This paper proposes one algorithm based on direction mean value difference to detect fingerprint center point. To realize this algorithm mainly includes detecting point direction of each pixel and configuring block patterns with 8×8 and 16×16 ranges. Experimental results show the algorithm has good robustness and can easily wipe off the false center point detected from the fingerprints.

Mutations having pleiotropic effects on polar organelle development (pod) in Caulobacter crescentus have been identified and shown to occur in at least 13 genes scattered throughout the genome. Mutations at each locus affect a unique combination of polar traits, suggesting that complex interactions occur among these genes. The DNA sequence of one of these genes, pleC, indicates that it is homologous to members of the family of histidine protein kinase genes. Membes of this family include the senor components of the bacterial two-component regulatory systems. Furthermore, in vitro experiments demonstrated that the PleC protein was capable of autophosphorylation. These results suggest that the PleC protein (and perhaps the proteins encoded by the other pod genes as well) regulates the expression of genes involved in polar organelle development through the phosphorylation of key regulatory proteins. The use of a phosphorelay system cued to internal changes in the cell would provide a mechanism for coordinating major changes in gene expression with the completion of specific cell cycle events.

Fluoralkylpolysiloxane was prepared using perfluoro octyl sulfuryl fluoride and terminal amino-silicone oil as reactants. Then, the isocyanate end capped PU prepolymer was synthesized by reacting isocyanate with a soft segment mixed by active amino-end-capping fluoralkylpolysiloxane and polyether glycol. The fluoralkylpolysiloxane modified PU was obtained after the PU prepolymer was cured by 3,3'- dichloro -4,4' - amino-diphenyl methane (MOCA). The structure, tensile properties, dynamic mechanical analysis and water contact angle of modified PU were investigated. The results show that, when the content of PFATPS was around 10%, the two phrases were compatible and FSPU had the optimal properties. The tensile strength and elongation at break increased by 26% and 32% respectively compared to that of the unmodified. In addition, the surface water contact angle increased by 38 degree and the damping capacity also had a considerable improvement.

Tone is an essential component for word formation in all tone languages. It plays a very important role in the transmission of information in speech communication. In this paper, we look at using support vector machines (SVMs) for automatic tone recognition in continuously spoken Mandarin. Wavelet transform and Teager Energy Operation (TEO) are used to detect the voiced segments. Considerable improvement has been achieved by adopting binary-SVMs scheme in a speaker-independent Mandarin tone recognition system.

Caulobacter crescentus differentiates prior to each cell division to form two different daughter cells: a monoflagellated swarmer cell and a nonmotile stalked cell. Thus, one might expect that developmentally expressed genes would be regulated by mechanisms different from those used to regulate the expression of the biosynthetic genes. To determine a consensus promoter sequence for genes involved in biosynthetic or housekeeping functions, DNA fragments containing the regulatory regions of the ilvD, ilvR, cysC, pleC, and fdxA genes were cloned. S1 nuclease protection mapping and primer extension techniques were used to identify the transcription initiation sites. Comparison of the regulatory regions of these genes with those of the published sequences of the ilvBN, rrnA, trpFBA, dnaA, dnaK, hemE, and rsaA genes has resulted in the identification of a putative promoter consensus sequence. The -35 region contains the sequence TTGACGS, which is similar to the Escherichia coli -35 region, while the -10 region, GCTANAWC, has a more balanced GC content than the corresponding region in E. coli. Oligonucleotide-directed site-specific mutagenesis of both the ilvBN and pleC promoters indicates that mutations that make a promoter more like the consensus result in increased promoter activity, while mutations decreasing similarity to the consensus result in decreased promoter activity.

The fdxA gene was identified upstream of and in the opposite direction from the Caulobacter crescentus cysC gene. Analyses of the nucleotide sequence and the deduced amino acid sequence of the fdxA gene demonstrated that it encodes a ferredoxin with a molecular mass of 12,080 Da. This ferredoxin has common structural features with ferredoxins that contain a [3Fe-4S] and a [4Fe-4S] cluster, including seven conserved cysteines responsible for the binding of the two clusters. A mutation in the fdxA gene was obtained, and the resulting strain did not produce one of the two ferredoxins (FdI) found in C. crescentus. Further experiments demonstrated that the fdxA gene is temporally expressed in C. crescentus and that FdI is required for completion of the cell cycle at 37 degrees C.

Induction of nod genes in Rhizobium and Bradyrhizobium species is dependent on the presence of plant-produced flavonoids, the NodD protein, and the cis-acting nod box promoter sequence. Although the nodD (nodD1) gene in Rhizobium species is constitutively expressed, nodD1 expression in Bradyrhizobium japonicum is inducible by isoflavones in a manner similar to that of the nodYABC operon. A consensus nod box sequence is found 5' of the nodYABC operon, whereas a presumptive, nod box-like sequence is found 5' of the nodD1 gene. As an initial step toward examining the nodD1 promoter, the transcriptional start sites of the nodD1 and nodYABC operons were determined and found to be 44 and 28 bp, respectively, downstream of their respective nod box sequences. A series of deletions of the nodD1 promoter were constructed and fused to the lacZ gene. Analysis of the activity of these deletions clearly showed that the divergent nod box sequence was essential for nodD1 induction by isoflavones or soybean seed extract. The induction of nodD1 expression requires NodD1, as tested in B. japonicum and in a heterologous system, Agrobacterium tumefaciens. On the basis of these data, we analyzed the published nod box sequences and propose a new consensus sequence composed of paired 9-bp repeats. Analysis of the nodD1 nod box and synthetic constructs of the nocYABC nod box indicate that at least two 9-bp repeats are required for NodD1-mediated induction. Furthermore, insertions between the paired repeats of the nodYABC nod box suggest that orientation of the repeats on opposite faces of the DNA helix is essential for maximum nod gene expression.

The expression of the nodD and nodYABC operons of Bradyrhizobium japonicum is repressed by the addition of ammonia. Repression of nodYABC expression is probably due to the effect on nodD since NodD positively regulates itself, as well as other nod operons. The effect of ammonia is independent of the known nitrogen regulatory protein, NtrC, and another regulatory protein for nitrogen fixation, NifA.

Purpose Previous studies have identified sequences encoding vascular endothelial growth factor (VEGF)-A and one of the VEGF receptors (VEGFR2, Flk-1, KDR) in lens fiber cells. The current study was undertaken to determine the distribution of VEGF-A protein in the lens, whether signaling through VEGF receptors occurs in lens cells, the pattern of VEGF-A expression during lens development, and the effect of hypoxia on VEGF-A expression. Methods VEGF-A and VEGFR2 were localized using immunocytochemistry. VEGF-A and VEGFR2 protein were identified and quantified by Western blot analysis. Activated (tyrosine phosphorylated) VEGFR2 was detected by immunoprecipitation with an anti-phosphotyrosine antibody followed by Western blot analysis with antibody to VEGFR2. Levels of VEGF-A mRNA were measured by quantitative PCR. Suturing the lids of adult mouse or rabbit eyes for 3 days was used to induce lens hypoxia. Results VEGFR2 sequences were present in adult human lens epithelial cells, and VEGF-A transcripts were detected in chicken embryo, adult human, and mouse lens epithelial cells. VEGF-A protein localized to the ends of mouse embryo lens fiber cells at developmental stages when the fetal vasculature was forming. At later stages, VEGF-A was distributed uniformly throughout the cytoplasm of cortical fiber cells. VEGFR2 was present in mouse lens epithelial and fiber cells and was tyrosine phosphorylated at all stages examined. VEGF-A protein was barely detectable in lens epithelial cells during the first postnatal week, but increased as the capillaries of the anterior pupillary membrane regressed. VEGF-A levels were highest in adult lenses. Suturing the eyelid caused an increase in VEGF-A mRNA and protein in lens epithelial and fiber cells. Conclusions VEGF-A secreted by lens cells may stimulate the formation of the fetal vasculature, but regression of these vessels is not likely to be caused by a reduction in VEGF-A production by the lens. An active VEGF-A signaling system of unknown function appears to be active in the lens. It is likely that VEGF-A expression is regulated by tissue hypoxia at all stages of lens development.

Genes that specify nodulation (nod genes) are only active in the free-living rhizobia or in the nodule initiation state of rhizobia. As soon as the repression of nod genes occurs in the bacteroids of the nodule, nifA is induced, while ntrC is inactivated and thus the nifA-mediated nif/fix genes are turned on. Limitation of available oxygen brings about the induction of nifA, which reflects the actual status of nif/fix gene activities in symbiotic state of rhizobia. Oxygen thus appears to be a major symbiotic signal to the expression of bacteroid nif/fix genes. Mutation of nifA or shortage of nifA product in wild-type rhizobia caused by the inhibition of multicopy nifH/fixA promoters leads to an abnormal development of nodules and premature degradation of bacteroids in nodules.Key words: nitrogen fixation, nodulation, nif/fix regulation, nifA mutant.