Black Hole Growth in Disk Galaxies Mediated by The Secular Evolution of Short Bars

<p>In a series of papers (Du et al. 2015, 2016, 2017a), we have developed realistic ”bars within bars” (S2B) systems using N-body simulations. The short bars of sub-kiloparsec radius have been hypothesized to be an important mechanism for driving gas inflows efficiently to small scale, feeding central BHs in the secular evolution. The growth of black holes (BHs) in disk galaxies lacking classical bulges, which implies an absence of significant mergers, appears to be driven by such secular processes. We quantify the maximum BH mass allowed by this mechanism with our numerical S2B models (Du et al. 2017b). We find that short bars can be destroyed quickly when BHs of mass Mbh 0.05%-0.2% of the total stellar mass (M*) are present. Thus, the dissolution of short inner bars is possible, perhaps even frequent, in the universe. An important implication of this result is that inner-bar-driven gas inflows may be terminated when BHs grow to 0.1%M* . We predict that 0.2%M* is the maximum mass of BHs allowed if they are fed predominately via inner bars. This value matches well the maximum ratio of BH-to-host-galaxy stellar mass observed in galaxies with pseudo-bulges and most nearby active galactic nucleus host galaxies. This hypothesis provides a novel explanation for the lower Mbh/M* in galaxies that have avoided significant mergers compared with galaxies with classical bulges.</p

Effects of UV radiation and temperature on Shiga toxin 2 protein content in <i>E. coli</i> O157:H7 EDL933 strain.

<p>(A) Representative Stx2A western blotting band. (B) Relative Stx2A protein content including only the major band. (C) Relative Stx2A protein content including all three bands. **: <i>P</i><0.01; **: <i>P</i><0.05. (Mean ± SEM; n = 3).</p

Quantitative PCR quantification of Stx2 prophage induction in the <i>E. coli</i> O157:H7 EDL933 strain with/without UV radiation at different temperatures.

<p>**: <i>P</i><0.01; **: <i>P</i><0.05. (Mean ± SEM; n = 3).</p

Investigation of Inhibition Properties of Sophorolipids for X65 Steel Corrosion in Simulated Oilfield Produced Water Saturated with Carbon Dioxide

The inhibiting effect of sophorolipids on the corrosion of X65 steel in the simulated oilfield produced water saturated with CO₂ was investigated by weight-loss measurement, polarization, electrochemical impedance spectroscopy, and scanning electronic microscope analysis. Results demonstrated that sophorolipids showed good inhibition performance for X65 steel corrosion in simulated oilfield produced water saturated with CO₂ and was found to be an anodic-type inhibitor

Movie S5 from <i>Ex vivo</i> gut culture for studying differentiation and migration of small intestinal epithelial cells

Representative Lgr5-derived epithelial cells and columnar epithelium in <i>ex vivo</i> guts at 7d. Lgr5^mT/mG <i>ex vivo</i> guts were induced by 250 μm 4-hydroxytamoxifen and the Lgr5-derived epithelial cells of <i>ex vivo</i> guts are shown at 7d by confocal microscope. Columnar epithelium was stained with violet color. This movie is related to figure 4e

Cyclopolymerization of Disiloxane-Tethered Divinyl Monomers To Synthesize Chirality-Responsive Helical Polymers

Synthetic polymers mimicking the stimuli-responsive coiled-coil structures of naturally occurring macromolecules such as motor proteins remain challenging. Here we report that chirality switchable quasi-double helical polymers can be synthesized by the free radical cyclopolymerization of the tetramethyl­disiloxane-tethered divinyl monomers. Two cyclopolymers (pbSt and pbMA) are obtained in this work, which in solid state are helical polymers investigated by both ECD and VCD. According to VCD analysis, the C–H deformation modes including C–H bending (mode I) and C–H rocking (mode II) in the main-chain helix show strong signals in VCD spectra and the plots of the division of VCD by IR, which have different responses to solvation histories or thermal treatment compared with other vibrational signals arising from side rings (especially signals from tetramethyl­disiloxane groups). After thermal treatment, all the side-ring VCD signals of both pbSt and pbMA are inverted, while the VCD signals from mode II of the main chain are unchanged. In cast films from chloroform solutions, pbSt shows only and inverted VCD signals arising from mode I and mode II of the main-chain helix, but not any VCD signals from side rings. <i>Ab initio</i> quantum calculation reveals that the change in the orientation of side-ring distortion against the main chain may account for the inversion of side-ring VCD signals. The responses of the experimental VCD spectra of the cyclopolymers can thus be rationalized based on the quantum calculation results. The main-chain helices of the cyclopolymers remained unchanged, while the side rings changed their distortion orientation during thermal treatment. In cast films from chloroform solutions, the polymer main-chain helix was inverted, hence inverted main-chain VCD; while the side rings might be randomly distorted, causing loss of VCD from side rings. Overall, the main-chain helices and side-ring pseudohelices can be switched independently. This work presents the first example that a single macromolecule can display such (quasi-)­double-helical conformation. Besides the theoretical value, this kind of chirality switchable quasi-double-helical polymer may find application in asymmetric catalyst, smart molecular devices, etc

Figure S4 from <i>Ex vivo</i> gut culture for studying differentiation and migration of small intestinal epithelial cells

<b>Effects of Wnt, BMP and Notch signaling on intestinal differentiation of <i>ex vivo</i> guts</b>. Small intestine from E13.5 embryos were isolated and cultured in medium containing 100 nM LDN-193189 (BMP signaling inhibitor; a), 10 μM DAPT (Notch signaling inhibitor; b), or 100 ng/ml Wnt 3a plus 500 ng/ml R-spondin1 (Wnt signaling activator; c). Relative mRNA expressions were tested using RT-qPCR. Data are represented as mean ± SEM. N=4. *: P < 0.05 versus CON. **: P < 0.01 versus CON

Effects of UV radiation and temperature on lambdoid prophage induction of <i>E. coli</i> O157:H7 EDL933 strain.

<p>**: <i>P</i><0.01; **: <i>P</i><0.05. (Mean ± SEM; n = 3).</p

Spontaneous lambdoid prophage induction in <i>E. coli</i> O157:H7 strains.

<p>(A) Statistical data of prophage induction (Means ± SEM, n = 3). (B) Representative pictures of plaque forming units of <i>E. coli</i> O157:H7 strains EDL933 and 493/98.</p

Figure S2 from <i>Ex vivo</i> gut culture for studying differentiation and migration of small intestinal epithelial cells

<b>Representative images of negative controls in immunofluorescent staining.</b> Sections were permeabilized, incubated with 5% goat serum overnight at 4°C, and incubated with respective fluorescent secondary antibodies for 2h at room temperature. Immunofluorescence was imaged using a fluorescence microscope. Scale bar is 200 μm