3,177 research outputs found
High-resolution Velocity Fields of Low-mass Disk Galaxies. I. CO Observations
This paper is the first in a series whose aim is to examine the relative distributions of dark and baryonic matter as a function of star formation history in a representative sample of low-mass disk galaxies. In this paper, we present high-resolution 12 CO(j=1→0) interferometry for a sample of 26 nearby dwarf galaxies that were obtained from the Combined Array for Research in Millimeter-wave Astronomy (CARMA). Among these 26 galaxies, 14 have good CO detections, including 6 galaxies previously detected in single-dish CO measurements and 8 newly detected ones. We find a linear correlation between the CO flux and the mid- and far-IR flux from the WISE and IRAS catalogs. Compared to the far-IR flux, the mid-IR flux may be a better indication of whether a galaxy contains sufficient CO for detection at the level of instrument sensitivity of CARMA. This correlation might prove to be useful in future studies to help choosing other CO targets for observation. The median molecular mass (including helium) of our galaxies is 2.8×10 8 M⊙, which is consistent with past observations for dwarf galaxies. The molecular content is weakly correlated with the dynamical mass, r-band luminosity and size of the galaxies. The median ratios of molecular mass versus dynamical mass and molecular mass versus r-band luminosity are M mol M dyn ≈ 0.035 and M mol L r ≈ 0.078M⊙ L r , ⊙, respectively, which are also consistent with past observations for dwarf galaxies
Improving soil phosphorus availability following application of Egypt rock phosphate and chicken litter biochar
Biochar has high concentrations of organic carbon, high porosity and surface area, improvement in soil physical properties including soil structure and water holding capacity. Chicken litter biochar had been used to improve soil phosphorus (P) availability for maize production but limited information on optimum rates of biochar and Egypt Rock Phosphate (ERP) to increase P availability. This research determined the rate of biochar and Egypt Rock Phosphate (ERP) that could increase soil P retention and availability. A laboratory study on P retention by different rates of biochar was evaluated in a leaching study for 30 days where the leachates were collected at three-day interval. Selected soil chemical properties before and after incubation were determined using standard procedures. The total P, pH, K, Mg, total C and P, exchangeable P, and water-soluble P, of the soils with biochar significantly higher than recommended fertilization practice. Around 75% biochar of 10 t ha-1 with 50% and 25% ERP of the existing recommendation showed significant retention and nutrients availability
High-resolution Velocity Fields of Low-mass Disk Galaxies. I. CO Observations
This paper is the first in a series whose aim is to examine the relative distributions of dark and baryonic matter as a function of star formation history in a representative sample of low-mass disk galaxies. In this paper, we present high-resolution 12 CO(j=1→0) interferometry for a sample of 26 nearby dwarf galaxies that were obtained from the Combined Array for Research in Millimeter-wave Astronomy (CARMA). Among these 26 galaxies, 14 have good CO detections, including 6 galaxies previously detected in single-dish CO measurements and 8 newly detected ones. We find a linear correlation between the CO flux and the mid- and far-IR flux from the WISE and IRAS catalogs. Compared to the far-IR flux, the mid-IR flux may be a better indication of whether a galaxy contains sufficient CO for detection at the level of instrument sensitivity of CARMA. This correlation might prove to be useful in future studies to help choosing other CO targets for observation. The median molecular mass (including helium) of our galaxies is 2.8×10 8 M⊙, which is consistent with past observations for dwarf galaxies. The molecular content is weakly correlated with the dynamical mass, r-band luminosity and size of the galaxies. The median ratios of molecular mass versus dynamical mass and molecular mass versus r-band luminosity are M mol M dyn ≈ 0.035 and M mol L r ≈ 0.078M⊙ L r , ⊙, respectively, which are also consistent with past observations for dwarf galaxies
Ergodic Jacobi matrices and conformal maps
We study structural properties of the Lyapunov exponent and the
density of states for ergodic (or just invariant) Jacobi matrices in a
general framework. In this analysis, a central role is played by the function
as a conformal map between certain domains. This idea goes
back to Marchenko and Ostrovskii, who used this device in their analysis of the
periodic problem
Visible inequality breeds more inequality
Experiments suggest that when people can see wealth inequality in their social network, this propels further inequality through reduced cooperation and reduced social connectivity. News & Views comment on Nishi et al, Nature 526, 2015, p. 426-429
E-cadherin can limit the transforming properties of activating β-catenin mutations
Wnt pathway deregulation is a common characteristic of many cancers. But only Colorectal Cancer predominantly harbours mutations in APC, whereas other cancer types (hepatocellular carcinoma, solid pseudopapillary tumours of pancreas) have activating mutations in β-catenin (CTNNB1). We have compared the dynamics and the potency of β-catenin mutations in vivo. Within the murine small intestine (SI), an activating mutation of β-catenin took much longer to achieve a Wnt deregulation and acquire a crypt-progenitor-cell (CPC) phenotype than Apc or Gsk3 loss. Within the colon, a single activating mutation of β-catenin was unable to drive Wnt deregulation or induce the CPC phenotype. This ability of β-catenin mutation to differentially transform the SI versus the colon correlated with significantly higher expression of the β-catenin binding partner E-cadherin. This increased expression is associated with a higher number of E-cadherin:β-catenin complexes at the membrane. Reduction of E-cadherin synergised with an activating mutation of β-catenin so there was now a rapid CPC phenotype within the colon and SI. Thus there is a threshold of β-catenin that is required to drive transformation and E-cadherin can act as a buffer to prevent β-catenin accumulation
Syntaxin 16 is a master recruitment factor for cytokinesis
Recently it was shown that both recycling endosome and endosomal sorting complex required for transport (ESCRT) components are required for cytokinesis, in which they are believed to act in a sequential manner to bring about secondary ingression and abscission, respectively. However, it is not clear how either of these complexes is targeted to the midbody and whether their delivery is coordinated. The trafficking of membrane vesicles between different intracellular organelles involves the formation of soluble N-ethylmaleimide–sensitive factor attachment protein receptor (SNARE) complexes. Although membrane traffic is known to play an important role in cytokinesis, the contribution and identity of intracellular SNAREs to cytokinesis remain unclear. Here we demonstrate that syntaxin 16 is a key regulator of cytokinesis, as it is required for recruitment of both recycling endosome–associated Exocyst and ESCRT machinery during late telophase, and therefore that these two distinct facets of cytokinesis are inextricably linked
Three weeks of interrupting sitting lowers fasting glucose and glycemic variability, but not glucose tolerance, in free-living women and men with obesity
Funding This work was supported by grants from the Novo Nordisk Foundation (NNF14OC0011493, NNF14OC0009941, NNF18CC0034900), Swedish Diabetes Foundation (DIA2018-357), Diabetes Wellness Sverige (1849-PG), Swedish Research Council (2015-00165, 2018-02389), the Strategic Research Programme in Diabetes at Karolinska Institutet (2009-1068), the Knut and Alice Wallenberg Foundation (2018-0094), and the Stockholm County Council (SLL20170159). D.D. is supported by the National Health and Medical Research Council and the Victorian Government’s OIS scheme. Acknowledgements We thank the Swedish Metabolomics Centre (Umeå University) for assisting with the lipidomic analysis and Mariam Nordstrand for efforts in the recruitment and screening of participants, and in muscle biopsy procedure. The current addresses for S.P. and B.M.G. are the School of Life Sciences, University of Nottingham, Nottingham, UK, and The Rowett Institute, University of Aberdeen, Aberdeen, UK, respectively.Peer reviewedPostprin
The uncertainties associated with sediment fingerprinting suspended and recently deposited fluvial sediment in the Nene river basin
The use of tracers within a sediment fingerprinting framework has become a commonly used technique for investigating the sources of fine sediment. However, uncertainties associated with tracer behaviour have been cited as major potential limitations to sediment fingerprinting methodologies. This paper aims to determine the differences between fingerprinting results derived using different groups of tracer properties and to determine the role of organic matter content, particle size, and within-source variability in tracer concentrations on the observed differences. A mean difference of 24.1% between the predicted contributions of sediment originating from channel banks was found when using different tracer groups. Mean differences between tracer group predictions were lower, at between 8% and 11%, when fingerprinting contributions from urban street dusts. Organic matter content and / or particle size showed little indication that they caused differences between tracer group predictions. The within-source variability in tracer concentrations and small contrasts between the tracer concentrations of different source groups were identified as probable causes of inherent uncertainty in the fingerprinting predictions. We determined that the ratio of the percentage difference between median tracer concentrations in the source groups and the average within-source tracer concentration coefficient of variation could indicate the likely uncertainty in model predictions prior to tracer use
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