The limit order book on different time scales

Financial markets can be described on several time scales. We use data from the limit order book of the London Stock Exchange (LSE) to compare how the fluctuation dominated microstructure crosses over to a more systematic global behavior.Comment: 11 pages, 7 figures, 2 tables, to appear in Proc. SPIE, Fluctuations and Noise 2007, Florenc

Kinematic Clues to Bar Evolution for Galaxies in the Local Universe: Why the Fastest Rotating Bars are Rotating Most Slowly

We have used Spitzer images of a sample of 68 barred spiral galaxies in the local universe to make systematic measurements of bar length and bar strength. We combine these with precise determinations of the corotation radii associated with the bars, taken from our previous study, which used the phase change from radial inflow to radial outflow of gas at corotation, based on high-resolution two-dimensional velocity fields in Hα taken with a Fabry-Pérot spectrometer. After presenting the histograms of the derived bar parameters, we study their dependence on the galaxy morphological type and on the total stellar mass of the host galaxy, and then produce a set of parametric plots. These include the bar pattern speed versus bar length, the pattern speed normalized with the characteristic pattern speed of the outer disk versus the bar strength, and the normalized pattern speed versus R, the ratio of corotation radius to bar length. To provide guidelines for our interpretation, we used recently published simulations, including disk and dark matter halo components. Our most striking conclusion is that bars with values of R < 1.4, previously considered dynamically fast rotators, can be among the slowest rotators both in absolute terms and when their pattern speeds are normalized. The simulations confirm that this is because as the bars are braked, they can grow longer more quickly than the outward drift of the corotation radius. We conclude that dark matter halos have indeed slowed down the rotation of bars on Gyr timescales. © 2017. The American Astronomical Society. All rights reserved.

Comparative internal kinematics of the H II regions in interacting and isolated galaxies: Implications for massive star formation modes

We have observed 12 interacting galaxy pairs using the Fabry-Perot interferometer GH αFaS (GalaxyHα Fabry-Perot system) on the 4.2-mWilliam Herschel Telescope at theObservatorio del Roque de los Muchachos, La Palma. We present here the Hα surface brightness, velocity and velocity dispersion maps for the 10 systems we have not previously observed using this technique, as well as the physical properties (sizes, Hα luminosities and velocity dispersion) of 1259 HII regions from the full sample. We also derive the physical properties of 1054 HII regions in a sample of 28 isolated galaxies observed with the same instrument in order to compare the two populations of HII regions. We find a population of the brightest HII regions for which the scaling relations, for example the relation between the Hα luminosity and the radius, are clearly distinct from the relations for the regions of lower luminosity. The regions in this bright population are more frequent in the interacting galaxies. We find that the turbulence, and also the star formation rate (SFR), are enhanced in the HII regions in the interacting galaxies. We have also extracted the Hα equivalent widths for the HII regions of both samples, and we have found that the distribution of HII region ages coincides for the two samples of galaxies. We suggest that the SFR enhancement is brought about by gas flows induced by the interactions, which give rise to gravitationally bound gas clouds which grow further by accretion from the flowing gas, producing conditions favourable to star formation. Key words: stars: formation -HII regions - galaxies: interactions - galaxies: ISM- galaxies: kinematics and dynamics

Young women's use of a microbicide surrogate: The complex influence of relationship characteristics and perceived male partners' evaluations

This is the post-print version of the article. The official published version can be found at the link below.Currently in clinical trials, vaginal microbicides are proposed as a female-initiated method of sexually transmitted infection prevention. Much of microbicide acceptability research has been conducted outside of the United States and frequently without consideration of the social interaction between sex partners, ignoring the complex gender and power structures often inherent in young women’s (heterosexual) relationships. Accordingly, the purpose of this study was to build on existing microbicide research by exploring the role of male partners and relationship characteristics on young women’s use of a microbicide surrogate, an inert vaginal moisturizer (VM), in a large city in the United States. Individual semi-structured interviews were conducted with 40 young women (18–23 years old; 85% African American; 47.5% mothers) following use of the VM during coital events for a 4 week period. Overall, the results indicated that relationship dynamics and perceptions of male partners influenced VM evaluation. These two factors suggest that relationship context will need to be considered in the promotion of vaginal microbicides. The findings offer insights into how future acceptability and use of microbicides will be influenced by gendered power dynamics. The results also underscore the importance of incorporating men into microbicide promotion efforts while encouraging a dialogue that focuses attention on power inequities that can exist in heterosexual relationships. Detailed understanding of these issues is essential for successful microbicide acceptability, social marketing, education, and use.This study was funded by a grant from National Institutes of Health (NIHU19AI 31494) as well as research awards to the first author: Friends of the Kinsey Institute Research Grant Award, Indiana University’s School of HPER Graduate Student Grant-in-Aid of Research Award, William L. Yarber Sexual Health Fellowship, and the Indiana University Graduate and Professional Student Organization Research Grant

Access and utilisation of primary health care services comparing urban and rural areas of Riyadh Providence, Kingdom of Saudi Arabia

The Kingdom of Saudi Arabia (KSA) has seen an increase in chronic diseases. International evidence suggests that early intervention is the best approach to reduce the burden of chronic disease. However, the limited research available suggests that health care access remains unequal, with rural populations having the poorest access to and utilisation of primary health care centres and, consequently, the poorest health outcomes. This study aimed to examine the factors influencing the access to and utilisation of primary health care centres in urban and rural areas of Riyadh province of the KSA

Multiparticle azimuthal correlations for extracting event-by-event elliptic and triangular flow in Au + Au collisions at sNN =200 GeV

We present measurements of elliptic and triangular azimuthal anisotropy of charged particles detected at forward rapidity 1&lt;|η|&lt;3 in Au + Au collisions at sNN=200 GeV, as a function of centrality. The multiparticle cumulant technique is used to obtain the elliptic flow coefficients v2{2},v2{4},v2{6}, and v2{8}, and triangular flow coefficients v3{2} and v3{4}. Using the small-variance limit, we estimate the mean and variance of the event-by-event v2 distribution from v2{2} and v2{4}. In a complementary analysis, we also use a folding procedure to study the distributions of v2 and v3 directly, extracting both the mean and variance. Implications for initial geometrical fluctuations and their translation into the final-state momentum distributions are discussed

Pseudorapidity Dependence of Particle Production and Elliptic Flow in Asymmetric Nuclear Collisions of p+Al, p+Au, d+Au, and ^{3}He+Au at sqrt[s_{NN}]=200 GeV.

Asymmetric nuclear collisions of p+Al, p+Au, d+Au, and ^{3}He+Au at sqrt[s_{NN}]=200  GeV provide an excellent laboratory for understanding particle production, as well as exploring interactions among these particles after their initial creation in the collision. We present measurements of charged hadron production dN_{ch}/dη in all such collision systems over a broad pseudorapidity range and as a function of collision multiplicity. A simple wounded quark model is remarkably successful at describing the full data set. We also measure the elliptic flow v_{2} over a similarly broad pseudorapidity range. These measurements provide key constraints on models of particle emission and their translation into flow

Inhibition of Inducible Nitric Oxide Synthase Attenuates Monosodium Urate-induced Inflammation in Mice

The present study elucidated the effect of the selective inducible nitric oxide synthase (iNOS) inhibitor N6-(1-iminoethyl)-L-lysine (L-NIL) on monosodium urate (MSU) crystal-induced inflammation and edema in mice feet. L-NIL (5 or 10 mg/kg/day) was administered intraperitoneally 4 h before injection of MSU (4 mg) into the soles of mice hindlimb feet. Twenty-four hours after MSU injection, foot thickness was increased by 160% and L-NIL pretreatment reduced food pad swelling in a dose dependent manner. Pretreatment of 10 mg/kg/day L-NIL significantly suppressed the foot pad swelling by MSU. Plasma level of nitric oxide (NO) metabolites and gene expression and protein level of iNOS in feet were increased by MSU, which was suppressed by L-NIL pretreatment. Similar pattern of change was observed in nitrotyrosine level. MSU increased the gene expression of tumor necrosis factor (TNF)-α and interleukin (IL)-1β and L-NIL pretreatment suppressed MSU-induced cytokines expression. The mRNA levels of superoxide dismutase and glutathione peroxidase1 were increased by MSU and L-NIL pretreatment normalized the gene expression. Phosphorylation of extracellular signal-regulated kinase 1/2 and p38 was increased by MSU, which was suppressed by L-NIL pretreatment. The mRNA levels of iNOS, TNF-α, and IL-1β were increased by MSU in human dermal fibroblasts, C2C12 myoblasts, and human fetal osteoblasts in vitro, which was attenuated by L-NIL in a dose dependent manner. This study shows that L-NIL inhibits MSU-induced inflammation and edema in mice feet suggesting that iNOS might be involved in MSU-induced inflammation

Cloud-scale Radio Surveys of Star Formation and Feedback in Triangulum Galaxy M 33: VLA Observations

Studying the interplay between massive star formation and the interstellar medium (ISM) is paramount to understand the evolution of galaxies. Radio continuum (RC) emission serves as an extinction-free tracer of both massive star formation and the energetic components of the interstellar medium. We present a multi-band radio continuum survey of the local group galaxy M 33 down to ~30 pc linear resolution observed with the Karl G. Jansky Very Large Array (VLA). We calibrate the star-formation rate surface density and investigate the impact of diffuse emission on this calibration using a structural decomposition. Separating the thermal and nonthermal emission components, the correlation between different phases of the interstellar medium and the impact of massive star formation are also investigated. Radio sources with sizes <~ 200 pc constitute about 36% (46%) of the total RC emission at 1.5 GHz (6.3 GHz) in the inner 18' x 18' (or 4kpc x 4kpc) disk of M 33. The nonthermal spectral index becomes flatter with increasing star-formation rate surface density, indicating the escape of cosmic ray electrons {from their birth places}. The magnetic field strength also increases with star-formation rate following a bi-modal relation, indicating that the small-scale turbulent dynamo acts more efficiently at higher luminosities and star-formation rates. Although the correlations are tighter in star-forming regions, the nonthermal emission is correlated also with the more quiescent molecular gas in the ISM. An almost linear molecular star-formation law exists in M 33 when excluding diffuse structures. Massive star formation amplifies the magnetic field and increases the number of high-energy cosmic ray electrons, which can help the onset of winds and outflows

Comprehensive assessment of spotty calcifications on computed tomography angiography: Comparison to plaque characteristics on intravascular ultrasound with radiofrequency backscatter analysis

Vascular Biology and Interventio