The curious case of offset bars : markers for a baby galaxy disk or signposts of an interaction with dark matter sub halos?

>Magister Scientiae - MScWe have used the Spitzer Survey of Stellar Structure in Galaxies (S⁴G) as a representative sample of the local universe (total of 2352 galaxies in S⁴G) to make a catalog of offset disk barred galaxies. Using the combined variation of the position angle and the ellipticity (provided by ellipse fit) and also through visual inspection, we have been able to identify all offset structures in S⁴G. While primary bars are present in 2=3 of the disk galaxies in the visible universe, offset bars have a much lower fraction. Of the ̴ 1500 (3.6µm images) disk galaxies available in S⁴G, we classified only 49 as offset barred disk galaxies. We have determined basic properties (bar to total luminosity ratio, bar length, disk scale-length and bars of offset bars shape) using GALFIT, a widely used galaxy decomposition software package. Our main conclusion is that all the offset bars are boxy, independent of their offset from the galaxy center, or the mass of the host galaxy. Additionally we find that, the early type offset bars seem to be more boxy than the late types. The comparison of our offset sample with two other samples, respectively, low mass and high mass normal barred galaxies ("normal" for bars located at the photometric center of the host galaxy), reveals them to be at an intermediate position between the two normal samples. The bar length, disk scale-length and bar to total luminosity ratio are on average larger than the low mass normal and smaller than high mass normal barred galaxies. We have found, overall, a tighter correlation between the disk and bar properties for offset bars in comparison to the two normal samples. Our explanation is that, although the offset has no visible impact on the global shape of the bars, the process responsible for these disturbances seems to affect the star formation rate such that their disk and bars are on average more active than the normal barred galaxies in the same mass range, but not enough to surpass normal barred galaxies with much higher mass

第828回千葉医学会例会・第6回磯野外科例会 88-3.

Western blotting was performed to examine the protein levels of Twist in the indicated cells; β-actin was used as control. (JPG 151 kb

Intramolecular O···H Hydrogen Bonding of Salicylic Acid: Further Insights from O 1s XPS and ¹H NMR Spectra Using DFT Calculations

Intramolecular hydrogen bonding (HB) is a complex phenomenon that extends beyond a simple valence event, affecting the core electrons of a molecule. Salicylic acid (SA) and its conformers provide an excellent model compound for studying intramolecular HB as the proton donor (H) and acceptor (O) can be toggled by rotating the C–O and C–C bonds to form up to seven potential conformers through various HB. In this study, we computationally investigated intramolecular interactions in SA conformers with and without such HB, by examining their calculated O 1s core electron-binding energy (CEBE) and 1H NMR chemical shifts validated using recent measurements. The quantum mechanically stable SA conformers are fully defined by three rotatable bonds in the compound, which are abstracted as SA(η1η2η3) digital structures, where ηi = 0 if the ηi angles match the most stable SA conformer (000) and ηi = 1 otherwise. Our findings suggest that the stability is dominated by the appearance of the intergroup intramolecular HB of Hp···O (where O is in the carboxylic acid functional group and Hp is the phenolic proton in −OHp), and η3 serves as a switch of such HB. As a result, the (η1η20) SA conformers containing such Hp···O HB are more stable than other SA conformers (η1η21) without such the Hp···O HB. The present density functional theory calculations reveal that this Hp···O HB results in splitting of the O 1s CEBEs of two hydroxyl groups (−OH) by up to 1 eV and deshielding the Hp proton 1H NMR (δHp) up to 11.68 ppm for the (η1η20) conformers. Without such Hp···O HB, the O 1s XPS binding energies of two −OH groups will be closely located in the same band, and the 1H NMR chemical shift of the Hp atom will be as small as an 4.09 ppm SA conformer [SA-G(101)]. The present study indicates that the O 1s CEBE splitting between two −OH groups serves as an indicator of the presence of the Hp···O HB in SA conformers, which is also supported by the 1H NMR results

Dual-Functional Emulsifying/Antifogging Coumarin-Containing Polymeric Micelle

Dual-functional emulsifying/antifogging polymeric micelles have been prepared by the self-assembly of poly­(2-(dimethylamino)­ethyl methacrylate-<i>co</i>-methyl methacrylate-<i>co</i>-7-acryloxy-4-methylcoumarin) P­(DMAEMA-<i>co</i>-MMA-<i>co</i>-AOM). On one hand, the polymeric micelles have spherical morphology and exhibit triple responsive behaviors. The sample with the DMAEMA/MMA/AOM molar ratio of 5/3/3 (T2) is chosen to investigate the influence of pH on the emulsifying performance, and the configuration of polymeric micelles on the oil/water interface is investigated. The amount of micelles arranged on the surface of solidified polymerized beads gradually decreases as the pH changes from 12 to 5, and then total phase separation and demulsification occur at pH 3. On the other hand, we prepare an effective antifogging coating by forming an interchain network (ICN) resulting from self-assembled micelles and photo-cross-linked coumarin units. The ICN-T2 coating can not only absorb water vapor rapidly but also avoid excessive swelling of the amphiphilic terpolymer, thus leading to excellent antifogging performance. To the best of our knowledge, the photo-cross-linkable coumarin derivative is first introduced into an antifogging polymer coating at the molecular level, successfully avoiding the use of chemical cross-linking agents. The coumarin-containing polymeric micelle may be applied in many industrial processes and will provide new insight into the interface or surface property of macromolecular materials

Accelerating Computation of Acidity Constants and Redox Potentials for Aqueous Organic Redox Flow Batteries by Machine Learning Potential-Based Molecular Dynamics

Due to the increased concern about energy and environmental issues, significant attention has been paid to the development of large-scale energy storage devices to facilitate the utilization of clean energy sources. The redox flow battery (RFB) is one of the most promising systems. Recently, the high cost of transition-metal complex-based RFB has promoted the development of aqueous RFBs with redox-active organic molecules. To expand the working voltage, computational chemistry has been applied to search for organic molecules with lower or higher redox potentials. However, redox potential computation based on implicit solvation models would be challenging due to difficulty in parametrization when considering the complex solvation of supporting electrolytes. Besides, although ab initio molecular dynamics (AIMD) describes the supporting electrolytes with the same level of electronic structure theory as the redox couple, the application is impeded by the high computation costs. Recently, machine learning molecular dynamics (MLMD) has been illustrated to accelerate AIMD by several orders of magnitude without sacrificing the accuracy. It has been established that redox potentials can be computed by MLMD with two separated machine learning potentials (MLPs) for reactant and product states, which is redundant and inefficient. In this work, an automated workflow is developed to construct a universal MLP for both states, which can compute the redox potentials or acidity constants of redox-active organic molecules more efficiently. Furthermore, the predicted redox potentials can be evaluated at the hybrid functional level with much lower costs, which would facilitate the design of aqueous organic RFBs

Chilling injury symptoms of ‘Hongyang’ kiwifruit.

<p>Representative pictures of ‘Hongyang’ kiwifruit after 90 days of cold storage followed by 5 days of shelf life at 20°C. (A) normal kiwifruit. (B) skin showing the brown symptom of CI (arrow). (C) normal flesh of kiwifruit. (D) flesh of kiwifruit showing the grainy symptom (arrow). (E) the cross-section of the normal flesh. (F) the cross-section of the flesh showing the grainy symptom (arrow). (G)the longitudinal section of the normal flesh. (H) the longitudinal section of the flesh showing the grainy symptom (arrow).</p

Effect of exogenous Put treatment on ethylene production rate of ‘Hongyang’ fruit.

<p>Kiwifruit were respectively immersed in 0 mM (control) and 2 mM putrescine (Put) for 10 min and then storage at 0°C and 90–95% relative humidity for 90 days. In storage time ‘+5’ denotes 5 days of shelf life at 20°C following storage at 0°C. Vertical bars represent standard error of means (n = 3). Asterisks show significant difference (<i>P <0</i>.<i>05</i>) for the samples between 2 mM Put treatment and control taken at the same time point.</p

Loading of principal components.

<p>Loading of principal components.</p

MOESM1 of Hemodynamics of cerebral bridging veins connecting the superior sagittal sinus based on numerical simulation

Additional file 1. The detail data about the difference between the anterior and posterior segments of bridging vein models