154 research outputs found

    A High-Density Linkage Map of the Ancestral Diploid Strawberry, Fragaria iinumae, Constructed with Single Nucleotide Polymorphism Markers from the IStraw90 Array and Genotyping by Sequencing

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    Fragaria iinumae Makino is recognized as an ancestor of the octoploid strawberry species, which includes the cultivated strawberry, Fragaria ×ananassa Duchesne ex Rozier. Here we report the construction of the first high-density linkage map for F. iinumae. The F. iinumae linkage map (Fii map) is based on two high-throughput techniques of single nucleotide polymorphism (SNP) genotyping: the IStraw90 Array (hereafter “Array”), and genotyping by sequencing (GBS). The F2 generation mapping population was derived by selfing F. iinumae hybrid F1D, the product of a cross between two divergent F. iinumae accessions collected from Hokkaido, Japan. The Fii map consists of seven linkage groups (LGs) and has an overall length of 451.7 cM as defined by 496 loci populated by 4173 markers: 3280 from the Array and 893 from GBS. Comparisons with two versions of the Fragaria vesca ssp. vesca L. ‘Hawaii 4’ pseudo-chromosome (PC) assemblies reveal substantial conservation of synteny and colinearity, yet identified differences that point to possible genomic divergences between F. iinumae and F. vesca, and/or to F. vesca genomic assembly errors. The Fii map provides a basis for anchoring a F. iinumae genome assembly as a prerequisite for constructing a second diploid reference genome for Fragaria

    Inter-comparison of Radio-Loudness Criteria for Type 1 AGNs in the XMM-COSMOS Survey

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    Limited studies have been performed on the radio-loud fraction in X-ray selected type 1 AGN samples. The consistency between various radio-loudness definitions also needs to be checked. We measure the radio-loudness of the 407 type 1 AGNs in the XMM-COSMOS quasar sample using nine criteria from the literature (six defined in the rest-frame and three defined in the observed frame): RL=log(L5GHz/LB)R_L=\log(L_{5GHz}/L_B), q24=log(L24μm/L1.4GHz)q_{24}=\log(L_{24\mu m}/L_{1.4GHz}), Ruv=log(L5GHz/L2500A˚)R_{uv}=\log(L_{5GHz}/L_{2500\AA}), Ri=log(L1.4GHz/Li)R_{i}=\log(L_{1.4GHz}/L_i), RX=log(νLν(5GHz)/LX)R_X=\log(\nu L_{\nu}(5GHz)/L_X), P5GHz=log(P5GHz(W/Hz/Sr))P_{5GHz}=\log(P_{5GHz}(W/Hz/Sr)), RL,obs=log(f1.4GHz/fB)R_{L,obs}=\log(f_{1.4GHz}/f_B) (observed frame), Ri,obs=log(f1.4GHz/fi)R_{i,obs}=\log(f_{1.4GHz}/f_i) (observed frame), and q24,obs=log(f24μm/f1.4GHz)q_{24, obs}=\log(f_{24\mu m}/f_{1.4GHz}) (observed frame). Using any single criterion defined in the rest-frame, we find a low radio-loud fraction of 5%\lesssim 5\% in the XMM-COSMOS type 1 AGN sample, except for RuvR_{uv}. Requiring that any two criteria agree reduces the radio-loud fraction to 2%\lesssim 2\% for about 3/4 of the cases. The low radio-loud fraction cannot be simply explained by the contribution of the host galaxy luminosity and reddening. The P5GHz=log(P5GHz(W/Hz/Sr))P_{5GHz}=\log(P_{5GHz}(W/Hz/Sr)) gives the smallest radio-loud fraction. Two of the three radio-loud fractions from the criteria defined in the observed frame without k-correction (RL,obsR_{L,obs} and Ri,obsR_{i,obs}) are much larger than the radio-loud fractions from other criteria.Comment: 12 pages, 7 figures, MNRAS submitte

    Smoking in film in New Zealand: measuring risk exposure

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    BACKGROUND: Smoking in film is a risk factor for smoking uptake in adolescence. This study aimed to quantify exposure to smoking in film received by New Zealand audiences, and evaluate potential interventions to reduce the quantity and impact of this exposure. METHODS: The ten highest-grossing films in New Zealand for 2003 were each analysed independently by two viewers for smoking, smoking references and related imagery. Potential interventions were explored by reviewing relevant New Zealand legislation, and scientific literature. RESULTS: Seven of the ten films contained at least one tobacco reference, similar to larger film samples. The majority of the 38 tobacco references involved characters smoking, most of whom were male. Smoking was associated with positive character traits, notably rebellion (which may appeal to adolescents). There appeared to be a low threshold for including smoking in film. Legislative or censorship approaches to smoking in film are currently unlikely to succeed. Anti-smoking advertising before films has promise, but experimental research is required to demonstrate cost effectiveness. CONCLUSION: Smoking in film warrants concern from public health advocates. In New Zealand, pre-film anti-smoking advertising appears to be the most promising immediate policy response

    The Rise and Fall of Passive Disk Galaxies: Morphological Evolution Along the Red Sequence Revealed by COSMOS

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    The increasing abundance of passive "red-sequence" galaxies since z=1-2 is mirrored by a coincident rise in the number of galaxies with spheroidal morphologies. In this paper, however, we show that in detail the correspondence between galaxy morphology and color is not perfect, providing insight into the physical origin of this evolution. Using the COSMOS survey, we study a significant population of red sequence galaxies with disk-like morphologies. These passive disks typically have Sa-Sb morphological types with large bulges, but they are not confined to dense environments. They represent nearly one-half of all red-sequence galaxies and dominate at lower masses (log Mstar < 10) where they are increasingly disk-dominated. As a function of time, the abundance of passive disks with log Mstar < 11 increases, but not as fast as red-sequence spheroidals in the same mass range. At higher mass, the passive disk population has declined since z~1, likely because they transform into spheroidals. We estimate that as much as 60% of galaxies transitioning onto the red sequence evolve through a passive disk phase. The origin of passive disks therefore has broad implications for understanding how star formation shuts down. Because passive disks tend to be more bulge-dominated than their star-forming counterparts, a simple fading of blue disks does not fully explain their origin. We explore several more sophisticated explanations, including environmental effects, internal stabilization, and disk regrowth during gas-rich mergers. While previous work has sought to explain color and morphological transformations with a single process, these observations open the way to new insight by highlighting the fact that galaxy evolution may actually proceed through several separate stages.Comment: 16 pages, Accepted version to appear in Ap

    The Morphology of Galaxies in the Baryon Oscillation Spectroscopic Survey

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    We study the morphology of luminous and massive galaxies at 0.3<z<0.7 targeted in the Baryon Oscillation Spectroscopic Survey (BOSS) using publicly available Hubble Space Telescope imaging from COSMOS. Our sample (240 objects) provides a unique opportunity to check the visual morphology of these galaxies which were targeted based solely on stellar population modelling. We find that the majority (74+/-6%) possess an early-type morphology (elliptical or S0), while the remainder have a late-type morphology. This is as expected from the goals of the BOSS target selection which aimed to predominantly select slowly evolving galaxies, for use as cosmological probes, while still obtaining a fair fraction of actively star forming galaxies for galaxy evolution studies. We show that a colour cut of (g-i)>2.35 selects a sub-sample of BOSS galaxies with 90% early-type morphology - more comparable to the earlier Luminous Red Galaxy (LRG) samples of SDSS-I/II. The remaining 10% of galaxies above this cut have a late-type morphology and may be analogous to the "passive spirals" found at lower redshift. We find that 23+/-4% of the early-type galaxies are unresolved multiple systems in the SDSS imaging. We estimate that at least 50% of these are real associations (not projection effects) and may represent a significant "dry merger" fraction. We study the SDSS pipeline sizes of BOSS galaxies which we find to be systematically larger (by 40%) than those measured from HST images, and provide a statistical correction for the difference. These details of the BOSS galaxies will help users of the data fine-tune their selection criteria, dependent on their science applications. For example, the main goal of BOSS is to measure the cosmic distance scale and expansion rate of the Universe to percent-level precision - a point where systematic effects due to the details of target selection may become important.Comment: 18 pages, 11 figures; v2 as accepted by MNRA

    Halide homogenization for low energy loss in 2-eV-bandgap perovskites and increased efficiency in all-perovskite triple-junction solar cells

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    Monolithic all-perovskite triple-junction solar cells have the potential to deliver power conversion efficiencies beyond those of state-of-art double-junction tandems and well beyond the detailed-balance limit for single junctions. Today, however, their performance is limited by large deficits in open-circuit voltage and unfulfilled potential in both short-circuit current density and fill factor in the wide-bandgap perovskite sub cell. Here we find that halide heterogeneity—present even immediately following materials synthesis—plays a key role in interfacial non-radiative recombination and collection efficiency losses under prolonged illumination for Br-rich perovskites. We find that a diammonium halide salt, propane-1,3-diammonium iodide, introduced during film fabrication, improves halide homogenization in Br-rich perovskites, leading to enhanced operating stability and a record open-circuit voltage of 1.44 V in an inverted (p–i–n) device; ~86% of the detailed-balance limit for a bandgap of 1.97 eV. The efficient wide-bandgap sub cell enables the fabrication of monolithic all-perovskite triple-junction solar cells with an open-circuit voltage of 3.33 V and a champion PCE of 25.1% (23.87% certified quasi-steady-state efficiency)

    Reductionism in Economics: Causality and Intentionality in the Microfoundations of Macroeconomics

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    In many sciences – physical, but also biology, neuroscience, and other life sciences – one object of reductionism is to purge intentionality from the fundamental basis of both explanations and the explanatory target. The scientifically relevant level – ontologically and epistemologically – is thought to lie deeper than the level of ordinary human interactions. In the material and living world, the more familiar is the less fundamental. In contrast, the economic world of day-to-day life – the world of market interactions – appears to be the relevant level. Macroeconomics is thought to provide an account that is above, not below or behind, ordinary economic decisionmaking. An advantage of a macroeconomic account is that it is possible to employ causal analysis of the economy as a whole analogous to the causal analysis of physical systems. The fear of many economists is that such analyses are untethered to ordinary economic decisionmaking. The object of reductionism in economics – the so-called microfoundations of macroeconomics – is adequately to ground or replace higher level causal analysis with an analysis of the day-to-day interactions of people. The object is not to purge intentionality, but to reclaim it. The paper will attempt to understand the key issues surrounding the microfoundations of macroeconomics from a perspectival realist perspective that elucidates the relationship between economists' methodological preference for microfoundations and need for macroeconomic analysis – that is, between economists' respect for the intentional nature of economic life and the need for a causal analysis of the economy. The paper favors metaphysical humility and methodological pragmatism

    A Strawberry KNOX Gene Regulates Leaf, Flower and Meristem Architecture

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    The KNOTTED-LIKE HOMEODOMAIN (KNOX) genes play a central role in maintenance of the shoot apical meristem. They also contribute to the morphology of simple and compound leaves. In this report we characterize the FaKNOX1 gene from strawberry (Fragaria spp.) and demonstrate its function in trasgenic plants. The FaKNOX1 cDNA was isolated from a cultivated strawberry (F.×ananassa) flower EST library. The sequence is most similar to Class I KNOX genes, and was mapped to linkage group VI of the diploid strawberry genome. Unlike most KNOX genes studied, steady-state transcript levels were highest in flowers and fruits. Transcripts were also detected in emerging leaf primordia and the apical dome. Transgenic strawberry plants suppressing or overexpressing FaKNOX1 exhibited conspicuous changes in plant form. The FaKNOX1 RNAi plants presented a dwarfed phenotype with deeply serrated leaflets and exaggerated petiolules. They also exhibited a high level of cellular disorganization of the shoot apical meristem and leaves. Overexpression of FaKNOX1 caused dwarfed stature with wrinkled leaves. These gain- and loss-of-function assays in strawberry functionally demonstrate the contributions of a KNOX domain protein in a rosaceous species
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