On the relation between the mass of Compact Massive Objects and their host galaxies

Supermassive black holes and/or very dense stellar clusters are found in the central regions of galaxies. Nuclear star clusters are present mainly in faint galaxies while upermassive black holes are common in galaxies with masses $\geq 10^{10}$ M$_\odot$. In the intermediate galactic mass range both types of central massive objects (CMOs) are found. Here we present our collection of a huge set of nuclear star cluster and massive black hole data that enlarges significantly already existing data bases useful to investigate for correlations of their absolute magnitudes, velocity dispersions and masses with structural parameters of their host galaxies. In particular, we directed our attention to some differences between the correlations of nuclear star clusters and massive black holes as subsets of CMOs with hosting galaxies. In this context, the mass-velocity dispersion relation plays a relevant role because it seems the one that shows a clearer difference between the supermassive black holes and nuclear star clusters. The $M_{MBH}-{\sigma}$ has a slope of $5.19\pm 0.28$ while $M_{NSC}-{\sigma}$ has the much smaller slope of $1.84\pm 0.64$. The slopes of the CMO mass- host galaxy B magnitude of the two types of CMOs are indistinguishable within the errors while that of the NSC mass-host galaxy mass relation is significantly smaller than for supermassive black holes. Another important result is the clear depauperation of the NSC population in bright galaxy hosts, which reflects also in a clear flattening of the NSC mass vs host galaxy mass at high host masses.Comment: 12 pages, 22 figures, 2 tables, accepted for publication in MNRA

Chain or Ring: Which One Is Favorable in Nitrogen-Rich Molecules N₆XH<i>_m</i>, N₈XH<i>_m</i>, and N₁₀XH<i>_m</i> (X = B, Al, Ga, <i>m</i> = 1 and X = C, Si, Ge, <i>m</i> = 2)?

A series of nitrogen-rich molecules N₆XH_<i>m</i>, N₈XH_<i>m</i>, and N₁₀XH_<i>m</i> (X = B, Al, Ga, <i>m</i> = 1 and X = C, Si, Ge, <i>m</i> = 2) consisting of N₃ and N₅ radicals, are systematically investigated by using B3LYP and B3PW91 DFT methods. It is found that for the nitrogen-rich molecules, the structures with N₃-chains (N₅-ring) are more stable than those containing a N₃-ring (N₅-chain). This result could be well-explained by the intrinsic stability of the N₃ and N₅ radicals and their charge distribution in nitrogen-rich molecules. The dissociation energies further indicate that the B-doped and C-doped structures are the most stable among the molecules with three elements of group 13 and 14, respectively. Energy decomposition analysis shows the bond of boron–nitrogen is stronger than that of carbon–nitrogen. Detailed bonding analysis demonstrates that the B–N bond is determined by σ and π interactions between the B and N atoms, whereas C–N bonds by only σ interactions. These results imply that the boron atom is more suitable than the carbon atom for building the nitrogen-rich molecules studied in this article

Cell Number Expansion analysis of MES and MEF cells after five days incubation under 1G or SMG.

<p>(A) The initial MES cells seeding number was 3×10⁴. The cell doubling curve was generated by dividing the cell number by10⁴ and then transforming the values to logarithm base2. (B) The initial MEF cells seeding number was 10⁵. The cell doubling curve was generated by dividing the cell number by10⁴ and then transforming the values to logarithm base2. The data represent mean ±SD of three independent experiments.</p

Effects of SMG on NADPH oxidase2 (Nox2) expression in <i>Mdc1</i>^<i>+/+</i> and <i>Mdc1</i>^<i>-/-</i> MEF cells.

<p>(A) Western blot analysis of Nox2 protein expression in <i>Mdc1</i>^{<b><i>+/+</i></b>} and <i>Mdc1</i>^{<b><i>-/-</i></b>} MEF cells exposed to 1G or SMG condition for 1 or 5days. GAPDH was used as an internal control. The representative results of three independent experiments were shown. (B) Quantitative comparison of Nox2 expression. Data were derived from three independent experiments as in A). The expression levels of Nox2 were normalized to the endogenous control GAPDH expression. The data represent mean ± SD of three independent experiments. Student’s t test, *P<0.05.</p

Effects of SMG on antioxidant enzyme activity in MES cells.

<p><i>Rad9</i>^{<b><i>+/+</i></b>} MES cells and <i>Rad9</i>^{<b><i>-/-</i></b>} MES cells were cultured under 1G and SMG for 1 and 5 days, respectively. The activities of the antioxidant enzymes in MES cell lysates were determined. (A) Histograms of superoxide dismutase enzyme activity. (B) Histograms of catalase enzyme activity. (C) Histogram of Glutahione peroxidase. The data represent mean ± SD of three independent experiments.</p

Effects of SMG on DNA damage in <i>Mdc1</i>^<i>+/+</i> and <i>Mdc1</i>^<i>-/-</i> MEF cells.

<p>Evaluation of DNA double strand break by neutral comet assay in <i>Mdc1</i>^{<b><i>+/+</i></b>} and <i>Mdc1</i>^{<b><i>-/-</i></b>} MEF cells cultured under 1G or SMG condition for 1 or 5 days. At least 50 cells for each condition were scored for comet tail moment. The data represent mean ± SD of three independent experiments. Student’s t test, *P<0.05.</p

Chemical Sensing on a Single SERS Particle

We report a new chemical sensing platform on a single surface-enhanced Raman scattering (SERS) particle. A cabbage-like Au microparticle (CLMP) with high SERS enhancement was applied as an ultrasensitive SERS substrate. A new Raman reporter bis­[4,4′-[dithiodiphenyl azo-phenol] (DTDPAP) was synthesized to display multiple fingerprints and high reactivity toward sodium dithionite. The reaction of DTDPAP with sodium dithionite was in situ monitored by SERS on a single CLMP. The DTDPAP fingerprint change is dependent on the sodium dithionite concentration, providing a simple and sensitive method for sodium dithionite profiling

Effects of SMG on DNA damage and apoptosis in <i>Rad9</i>^<i>+/+</i> and <i>Rad9</i>^<i>-/-</i> MES cells.

<p>(A) Evaluation of DNA double strand break by neutral comet assay in <i>Rad9</i>^{<b><i>+/+</i></b>} and <i>Rad9</i>^{<b><i>-/-</i></b>} MES cells cultured under 1G or SMG condition. Time points were 1, 2, 3, 4 and 5 days. At least 50 cells for each condition were scored for comet tail moment. (B) Flow cytometric analysis of γ-H2AX formation in <i>Rad9</i>^{<b><i>+/+</i></b>} and <i>Rad9</i>^{<b><i>-/-</i></b>} mMES cells cultured under 1G or SMG condition for 1 or 5 days. (C) Evaluation of DNA damage by alkaline comet assay in <i>Rad9</i>^{<b><i>+/+</i></b>} and <i>Rad9</i>^{<b><i>-/-</i></b>} MES cells cultured under 1G or SMG condition for 1 or 5 days. At least 50 cells for each condition were scored for comet tail moment. (D) Evaluation of DNA damage by alkaline comet assay in <i>Rad9</i>^{<b><i>-/-</i></b>} MES cells with ectopic expression of <i>Rad9</i> (<i>Rad9</i>^{<b><i>-/-</i></b>}<i>+Rad9</i> MES cells) cultured under 1G or SMG condition for 1 or 5 days. At least 50 cells for each condition were scored for comet tail moment. (E) Flow cytometric analysis of <i>Rad9</i>^{<b><i>+/+</i></b>} and <i>Rad9</i>^{<b><i>-/-</i></b>} MES cells cultured under 1G or SMG condition for 1 day to assess apoptosis using Annexin V labeling. Experiments were performed three times and representative analyses are shown (upper). The lower part is the quantitative comparison of apoptosis between the 1G Group and the SMG Group. The data represent mean ± SD of at least three independent experiments. Student’s t test, *P<0.05.</p

Characterizing Binding of Small Molecules. II. Evaluating the Potency of Small Molecules to Combat Resistance Based on Docking Structures

Drug resistance severely erodes the efficacy of therapeutic treatments for many diseases. Assessing the potency of a drug lead to combat resistance is no doubt critical for designing new drugs or new therapeutic combinations. Virtual screening is often the first step in drug discovery and a challenging problem is to accurately predict the resistant profile of an inhibitor based on the docking structures. Using a well studied system HIV-1 protease, we have illustrated the success of a computational method called MIEC-SVM on tackling this problem. We computed molecular interaction energy components (MIECs) between the ligand and the protease residues to characterize the docking poses, which were input to support vector machine (SVM) to distinguish resistant from nonresistant mutants. More importantly, the method is able to predict resistant profiles for new drugs based on the docking structures as indicated by its satisfactory performance in leave-one-drug-out and leave-drug/mutants-out tests. Therefore, the MIEC-SVM method can also facilitate designing effective therapeutic combinations by combining drugs with complementary resistant profiles

Effects of SMG on NADPH oxidase2 (Nox2) and NADPH oxidase4 (Nox4) expression in <i>Rad9</i>^<i>+/+</i> and <i>Rad9</i>^<i>-/-</i> MES cells.

<p>(A) Quantitative real-time PCR analysis of Nox2 mRNA expression in <i>Rad9</i>^{<b><i>+/+</i></b>} and <i>Rad9</i>^{<b><i>-/-</i></b>} MES cells exposed to 1G or SMG condition for 1 or 5 days. The expression levels of Nox2 were normalized to the endogenous control GAPDH expression. (B) Quantitative real-time PCR analysis of Nox4 mRNA expression in <i>Rad9</i>^{<b><i>+/+</i></b>} and <i>Rad9</i>^{<b><i>-/-</i></b>} MES cells exposed to 1G or SMG condition for 1 or 5 days. The expression levels of Nox4 were normalized to the endogenous control GAPDH expression. (C) Western blot analysis of Nox2 protein expression in <i>Rad9</i>^{<b><i>+/+</i></b>} and <i>Rad9</i>^{<b><i>-/-</i></b>} MES cells exposed to 1G or SMG condition for 1 or 5 days. GAPDH was used as an internal control. The representative results of three independent experiments were shown. (D) Quantitative comparison of Nox2 expression. Data were derived from three independent experiments. The expression levels of Nox2 protein were normalized to the endogenous control GAPDH protein expression. The data represent mean ± SD of three independent experiments. Student’s t test, *P<0.05.</p