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The seam hole type carbonate didn't touch type drill in the cave reservoir oil and gas resources is rich, but due to the large difference of unused reservoir capacity, capacity of main control factors and the evaluation model is not clear, so the reservoir is difficult to reasonable and effective development, in order to improve the cave reservoir development effect, find the factors influencing the cave reservoir capacity of the master,This article through to carry out the cave type carbonate reservoir capacity model test, the cave reservoir productivity prediction model is set up and analyze the factors affecting capacity, studies have shown that the wellbore storage coefficient and skin factor of cave type carbonate reservoir had a greater influence on the vertical well productivity, this paper research content for the cave type of carbonate reservoir reserves producing has a certain guiding significance.

A method for the iodine-catalyzed conjugation of soybean oil was developed, and the conjugated product was analyzed by UV, IR, and 1H NMR. The results indicated that the optimal conditions for conjugation included a temperature of 180°C, a catalyst loading of 0.5 wt.% and a reaction time of 3 h, at which the concentration of conjugated linoleic acid was 1.51 mol L-1, with 92 % conversion, the CLNA reached 0.225 mol L-1 when the temperature was 130°C, a catalyst loading of 0.5 wt.%, and a reaction time of 3 h with a conversion rate of 99.9 %. The reaction predominantly produced trans-trans, trans-cis and cis-trans isomers. It was also revealed that the conjugation of linolenic acid was much faster than that of linoleic acid. The method possessed the advantages of a short procedure, a high conversion rate, and no methyl esterification of the raw material, and it was an environmentally friendly technology that does not use solvents.

Vaccination is an effective strategy to prevent leptospirosis, a global zoonotic disease caused by infection with pathogenic Leptospira species. However, the currently used multiple-valence vaccine, which is prepared with whole cells of several Leptospira serovars, has major side effects, while its cross-immunogenicity among different Leptospira serovars is weak. LipL32, LipL21 and 2 OmpL1 have been confirmed as surface-exposed antigens in all pathogenic Leptospira strains, but their immunoprotective efficiency needs to be improved. In the present study, we generated a fusion gene lipL32/1-lipL21-ompL1/2 using primer-linking PCR and an engineered E. coli strain to express the recombinant fusion protein rLipL32/1-LipL21-OmpL1/2 (rLLO). Subsequently, the expression conditions were optimized using a central composite design that increased the fusion protein yield 2.7-fold. Western blot assays confirmed that rLLO was recognized by anti-rLipL32/1, anti-rLipL21, and anti-rOmpL1/2 sera as well as 98.5% of the sera from leptospirosis patients. The microscopic agglutination test (MAT) demonstrated that rLLO antiserum had a stronger ability to agglutinate the strains of different Leptospira serovars than the rLipL32/1, rLipL21, and rOmpL1/2 antisera. More importantly, tests in hamsters showed that rLLO provided higher immunoprotective rates (91.7%) than rLipL32/1, rLipL21 and rOmpL1/2 (50.0-75.0%). All the data indicate that rLLO, a recombinant fusion protein incorporating three antigens, has increased antigenicity and immunoprotective effects, and so can be used as a novel immunogen to develop a universal genetically engineered vaccine against leptospirosis.

Leptospirosis caused by pathogenic Leptospira species is a worldwide zoonotic 2 infectious disease, but the mechanisms of leptospiral internalization remain poorly understood. Here, we report that mouse J774A.1 macrophages expressed integrin-subfamily proteins (ITGB1, ITGB2 and ITGB3). Antibody blockage and siRNA-based knockdown of ITGB1 decreased the internalization of leptospires into mouse J774A.1 macrophage cells. The internalization required focal adhesion kinase (FAK) activation in J774A.1 cells rather than phosphoinositide-3-kinase (PI3K), and microfilament rather than microtubule aggregation during infection. The data indicated that the ITGB1/FAK/microfilament signaling pathway is responsible for leptospiral internalization in mouse macrophages.

Leptospirosis caused by Leptospira is a worldwide zoonotic disease. The 2 spirochete can efficiently invade host cells and spread from blood into internal organs, but the mechanisms of leptospiral internalization into different host cells remain poorly understood. Adhesion of leptospires to the ECM (extracellular matrix) initiated leptospire internalization in macrophage cell-lines THP-1, J774A.1, and in human umbilical epithelial cells (HUVEC). We assessed the distribution of ECM , including fibronectin (FN), laminin and collagens 1-4 (COL1-COL4) in different cells. FN was expressed in THP-1 and J774A.1 cells, and FN, LN, COL3 and COL4 were expressed in HUVEC. Then, we found leptospires adhered to FN, LN, COL3 and COL4. The most important intracellular leptospires in macrophages (THP-1 and J774A) significantly decreased when leptospires were pre-blocked with FN This indicates that FN has an important role in the adherence to and entry of leptospires in macrophages, while in HUVEC, FN, LN, COL3 and COL4 assume this role.

Ti-45Al-7Nb alloys are produced by liquid-metal-cooling (LMC) directional solidification (DS) furnace with different temperature gradients (G) at a range of 40–80 K/cm. The growth directions of primary β phases and the deflection angles relative to the 〈100〉β direction were investigated. The solidification pathway of alloy is: Liq. → Liq. + β → β → β + α → α + γ → lamella (α2 + γ) + B2. Primary dendrite arm spacing λ reduced from 611.4 µm to 508.7 µm when G increased from 40 K cm−1 to 80 K cm−1. Grains with lamellar orientation aligned at the angles of 12–15° and 55° to growth direction were favored for various G. The orientations of the γ lamellas in steady-state regions were identified by the electron backscattered diffraction analysis (EBSD). The results indicated that the growth directions of primary bcc-β dendrites were 〈211〉β and 〈110〉β at 40 K/cm, 〈210〉β and 〈211〉β at 50 K/cm and 〈211〉β at 80 K/cm, the deflection angle of 〈211〉β relative to 〈100〉β direction is 35.3°.

A common strategy by which bacterial pathogens reside in humans is by shifting from a virulent lifestyle, (systemic infection), to a dormant carrier state. Two major serovars of Salmonella enterica, Typhi and Typhimurium, have evolved a two-component regulatory system to exist inside Salmonella-containing vacuoles in the macrophage, as well as to persist as asymptomatic biofilms in the gallbladder. Here we present evidence that SsrB, a transcriptional regulator encoded on the SPI-2 pathogenicity-island, determines the switch between these two lifestyles by controlling ancestral and horizontally-acquired genes. In the acidic macrophage vacuole, the kinase SsrA phosphorylates SsrB, and SsrB~P relieves silencing of virulence genes and activates their transcription. In the absence of SsrA, unphosphorylated SsrB directs transcription of factors required for biofilm formation specifically by activating csgD (agfD), the master biofilm regulator by disrupting the silenced, H-NS-bound promoter. Anti-silencing mechanisms thus control the switch between opposing lifestyles.

Microstructural refinement by two steps heat treatment in Ti-47Al-2Cr-2Nb at.% alloy, with samples' dimension of ⌀ 15 mm × 80 mm, is studied in this paper. A coarse fully lamellar microstructure can be refined to a near gamma (NG) one with a grain size of ∼ 180 μm by one step heat treatment of 1150°C for 12 h. The instability of initial structure plays an important role in the transformation. Some samples are subsequently treated at 1280°C for 2 h, the NG structure is further converted to a new lamellar structure through α laths precipitated with different directions within each γ grain and room temperature tensile elongation of the alloy is reached to a value of 1.28% after two steps heat treatments.