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The purpose of this work was to develop accurate calibration standards which were fully characterized in terms of uniformity and concentration using fundamental measuring methods. Three similar sets of vacuum deposits were commercially made, each set containing the single deposits CuS, KCl, CaF2, Cr, Fe, Cu, RbNO3, SrF2, MoO3 , BaF2, and Pb. Thickness variations in each deposit were measured with PIXEA (proton induced x-ray excitation analysis) measurements taken at 6 to 8 positions along the deposit diameters. Relative elemental concentrations on corresponding deposits from each set were measured using multiple XRF intercomparisons. One set of deposits was destructively analyzed at the National Bureau of Standards with isotope dilution thermal ionization mass spectrometry (IDMS) in order to calibrate the remaining sets of vacuum deposits. The calibrated deposits were compared with standards from two commercial sources. For seven elements heavier than chlorine there was an average deviation of 13.5% between the calibrated deposits and the commercial standards. Disagreements as large as 15% were observed between standards from the two commercial suppliers.
We present VELOCIraptor, a massively parallel galaxy/(sub)halo finder that is also capable of robustly identifying tidally disrupted objects and separate stellar halos from galaxies. The code is written in C++11, use the Message Passing Interface (MPI) and OpenMP Application Programming Interface (API) for parallelisation, and includes python tools to read/manipulate the data products produced. We demonstrate the power of the VELOCIraptor (sub)halo finder, showing how it can identify subhalos deep within the host that have negligible density contrasts to their parent halo. We find a subhalo mass-radial distance dependence: large subhalos with mass ratios of ≳10−2 are more common in the central regions than smaller subhalos, a result of dynamical friction and low tidal mass loss rates. This dependence is completely absent in (sub)halo finders in common use, which generally search for substructure in configuration space, yet is present in codes that track particles belonging to halos as they fall into other halos, such as hbt+. VELOCIraptor largely reproduces the dependence seen without tracking, finding a similar radial dependence to hbt+ in well-resolved halos from our limited resolution fiducial simulation.
Full potential of African tomato has not been tapped due to lack of information regarding its characterization. The aim of this work was to study the diversity of 17 African tomato landraces collected from Solanaceae gene bank – Tanzania. Evaluation was done using Complete Random Block Design. Morphological data collected were subjected to GenStat's and Darwin6 software. RNA was extracted from leaf samples, fruits at three ripening stages using modified Trizol method and sequencing done using Illumina sequencing platform. The raw reads were filtered and analysed using the Bioinformatics tools. Phenotypically, the landraces clustered into three clusters dendrogram representation. Clustering was attributed by phenotypic variation. Analysis of variance showed significant phenotypic variations among the landraces (P < 0.05). A total of 115,965 validated single nucleotide polymorphisms (SNPs) were mined from the 303,754,051 high-quality filtered reads. Molecular characterization showed significant variation within the landraces at fruit development stages. Unlike the phenotypic variation, phylogenetic tree representation grouped the 17 landraces according to their geographical location with some landraces from different countries grouping together. The findings of this study reveal significant morphological variation among African tomato contributed by plant height, leaf blade length, leaf blade width and fruit width. Positive correlation between fruit width and yield (r = 0.93, P < 0.01) was observed. Results of this study reveal that there is admixture of landraces from various geographical locations. Morphological characterization of African tomato can only lay a foundation but it does not reveal genetic diversity. The transcriptome SNP analysis revealed significant variation among the African tomato according to their geographical location.
The controls on rapid surface lake drainage on the Greenland ice sheet (GrIS) remain uncertain, making it challenging to incorporate lake drainage into models of GrIS hydrology, and so to determine the ice-dynamic impact of meltwater reaching the ice-sheet bed. Here, we first use a lake area and volume tracking algorithm to identify rapidly draining lakes within West Greenland during summer 2014. Second, we derive hydrological, morphological, glaciological and surface-mass-balance data for various factors that may influence rapid lake drainage. Third, these factors are used within Exploratory Data Analysis to examine existing hypotheses for rapid lake drainage. This involves testing for statistical differences between the rapidly and non-rapidly draining lake types, as well as examining associations between lake size and the potential controlling factors. This study shows that the two lake types are statistically indistinguishable for almost all factors investigated, except lake area. Thus, we are unable to recommend an empirically supported, deterministic alternative to the fracture area threshold parameter for modelling rapid lake drainage within existing surface-hydrology models of the GrIS. However, if improved remotely sensed datasets (e.g. ice-velocity maps, climate model outputs) were included in future research, it may be possible to detect the causes of rapid drainage.
The ultrafast charge dynamics following the interaction of an ultra-intense laser pulse with a foil target leads to the launch of an ultra-short, intense electromagnetic (EM) pulse along a wire connected to the target. Due to the strong electric field (of the order of
) associated to such laser-driven EM pulses, these can be exploited in a travelling-wave helical geometry for controlling and optimizing the parameters of laser accelerated proton beams. The propagation of the EM pulse along a helical path was studied by employing a proton probing technique. The pulse-carrying coil was probed along two orthogonal directions, transverse and parallel to the coil axis. The temporal profile of the pulse obtained from the transverse probing of the coil is in agreement with the previous measurements obtained in a planar geometry. The data obtained from the longitudinal probing of the coil shows a clear evidence of an energy dependent reduction of the proton beam divergence, which underpins the mechanism behind selective guiding of laser-driven ions by the helical coil targets.
We have measured the distribution of polarized emission from the radio galaxies NGC315, NGC6251, DA240, 3C236 and 3C326 at 327 MHz (92 cm wavelength) with the Westerbork Synthesis Radio Telescope (WSRT). These radio galaxies were all selected for observation because they exhibited degrees of polarization as high as 60 or 70 percent at 610 MHz (49 cm wavelength) and because they all have angular sizes greater than about 20 arcmin. Therefore they are still well-resolved by the WSRT at 92 cm wavelength. All sources in the sample exhibit significant linear polarization at 92 cm wavelength. Some depolarization does occur in NGC315 and 3C326 but parts of 3C236, DA240 and NGC6251 appear not to depolarize to 92 cm. Assuming an ordered, equipartition magnetic field, we find that the density of thermal depolarizing material in these radio galaxies is very low, typically about 1 × 10−5 cm−3 or less. Therefore these radio galaxies may represent distributions of pure magnetic fields and relativistic particles on scales of several hundred kiloparsecs or more.
Moss et al. (2006) provided comments and criticisms of our recent paper in this journal (Hall et al. 2005). We can appreciate the need for promoting vigorous dialogue among those interested in the research of early sites along the New World Pacific Margin and thus welcome their intervention; however, we are compelled to respond because they raise several points that require clarification and introduce a critical error that must be corrected.
Radiocarbon dates together with geoarchaeological, soil, and lithic analyses are presented to describe archaeological site 35-CS-9 in Bandon Ocean Wayside State Park, Oregon, northwestern USA. One of the few Oregon middle-Holocene coastal sites that includes sediments and artifacts dating to the early Holocene and possibly to the late Pleistocene, it was recorded in 1951 and surface surveyed by archaeologists in 1975, 1986, and 1991, but its depth and antiquity were not tested. In February 2002, we studied the site's stratigraphy and sediments and described 8 strata from the aeolian surface to bedrock at 350 cm depth. Soil samples taken from a cut bank for texture classification, particle size analysis, pH, carbon content, and chemical analysis suggested that the site represented a complete history of Holocene deposits. Excavation of 2 test units in August 2002 uncovered substantial lithic and charcoal remains that confirm a protracted middle-Holocene occupation and suggest that human occupation began in the early Holocene. Charcoal recovered at 235–245 cm dated to 11,000 14C BP, and the deepest lithic artifact was recovered in a level at 215–225 cm. Whether the human occupation was continuous throughout the Holocene, and whether it began in the early Holocene or in the late Pleistocene, can only be determined with further excavations.
In the framework of our high-frequency survey of giant radio galaxies with the Effelsberg 100-m telescope (Klein et al., 1994; Saripalli et al., 1995) we have obtained radio continuum maps of NGC6251, a source of 1.5 Mpc size (H0 = 75km s–1Mpc–1). Together with low-frequency WSRT observations (Willis & O'Dea, 1990), these measurements form a unique data base which for the first time allows thorough studies of the spectral index over a large frequency range. Theoretical models of particle ageing have been fitted to the spectrum to determine particle ages and other relevant physical parameters. Because of the immense size of NGC6251 these numbers provide information about the physics of the surrounding intergalactic medium.
The Book Annexed of 1662, as printed by the Queen’s Printers from the manuscript authenticated by the signatures of the members of both Houses of either Convocation, and annexed to the Act of Uniformity of 1662, shews no consistency in printing the Lord’s Prayer, and almost every time it occurs it is spelt or punctuated in a different way. But the variants are small, and in this Book the phrasing of the Prayer for public recitation appears in the following form:—
Our Father, which art in heaven. Hallowed be thy name. Thy kingdom come. Thy will be done in earth as it is in heaven. Give us this day our daily bread, And forgive us our trespasses, As we forgive them that trespass against us; And lead us not into temptation, But deliver us from evil. Amen.
Anyone reading the Solemn Prayers of Good Friday in the Roman rite is at once struck by the clear distinction which exists between the biddings and the collects of this ancient intercession both in language and in rhythm, and closer examination shows that whereas the biddings are almost destitute of rhythmic endings, showing only four in the nine biddings (two each in Biddings VI and VII), the collects abound in them, and not one of the nine collects is without at least one. This enables us to conclude that the biddings are earlier than the collects. For it is known that Roman liturgical composition, like the work of the papal chancery, conformed to the principles of the cursus from some time in the fourth century until the middle of the seventh. Presence of rhythmic endings is therefore useless for dating a document within this period, but in the case of writings before or after it, attention to the presence or absence of cursus can give a good indication of date. The cursus became the rule in the papal chancery from the time of Siricius (384-98), and disappeared after St Gregory the Great (604), and in the case of liturgical composition it prevailed roughly from 350 or a little later until about 650. The collects of the three ancient Roman sacramentarles abound in rhythmic endings. Dom Mocquereau collected about 1030 clausulae from the Leonine Sacramentary, of which only ten did not conform to the rules of the cursus. The Gelasian and Gregorian Sacramentarles show a like adherence to this literary principle, and their prayers nearly all date from within the classic period of the cursus, from the fourth to the seventh centuries.
Mediana is a term peculiar to Roman liturgy and is applied to the fifth Sunday in Lent, to the Wednesday and Saturday which precede this Sunday, and to the week embracing these three days. The term first occurs in a letter of Pope Gelasius, written in 494, in which he says that ordinations of priests and deacons should only be performed at certain seasons on Saturday evening, namely the fasts of the fourth, seventh and tenth months, which are the original Embertides, on the first Saturday in Lent, which is in the fourth and later Embertide, and on the Saturday medianae quadragesimae. The term occurs again in the next century when Pope Pelagius I (556–561) appointed this mediana septimana paschae as a season for ordinations. The text of Gelasius is quoted in the Liber Diurnus, of which the earliest manuscript dates from the seventh to the eighth century; in a letter of Gregory II of 715; and in the eleventh Canon of the Roman Council of 743.
In July 1995, the United States requested the establishment of the first Panel under Chapter 20 procedures of the North American Free Trade Agreement (NAFTA) and challenged Canada's duties on its “supply-managed” dairy, poultry, egg, barley, and margarine products. These industries had grown and prospered under supply management – a system intended to establish stability in a domestic market afflicted by unpredictable production cycles. The import restrictions were designed in conformity with the international trade rules as set out in the General Agreement of Tariffs and Trade (GATT). These rules changed in 1995 as a result of the WTO Agreement on Agriculture under which Canada and WTO members replaced quantitative import restrictions with tariffs and tariff-rate quotas. The United States claimed that the duties contravened the basic NAFTA obligation to not rahe tariffs. Canada countered that the new tariff rates were justified under the new WTO Agreement on Agriculture that had been negotiated in Geneva after NAFTA. The resulting decision in favour of Canada was both praised for its consideration of the case in the context of the complex interplay of relevant trade obligations and criticized for finding “an implied bargain among negotiators … that was never struck.” The Panel assumed that if tariff eqivalents could not be applied – which in effed would render the WTO Agreement on Agriculture inoperative – the result would be that the parties would be entitled to apply Article XI restrictions as if the Uruguay Round had never happened. The logic was impeccable – the NAFTA was “not to be read in clinical isolation from public international law.”
The Westerbork Synthesis Radio Telescope (WSRT) has now been used to make source surveys at frequencies of 610 and 1415 MHz. This paper summarizes the results concerning source counts and anisotropies in the distribution of sources from those surveys not concerned with clusters of galaxies.
NGC 6251, a 14th mag elliptical galaxy, was shown by Waggett et al. (1977) to have large-scale radio emission features with a total angular extent of ∼ 1.1°, which corresponds to a projected linear size of about 1.7 Mpc (HO = 75 km s−1 Mpc−1). A bright radio jet links a central core source embedded in NGC 6251 to the extended emission on the northwest side of the galaxy.
Spectral index distributions can be indicated conveniently by gSv1(αv1,v2), i.e. the distribution of the two-point spectral index between frequencies v1 and v2 for a sample of radio sources complete to flux density S at the selection frequency v1 (flux densities will be expressed in Jy and frequencies in GHz). Such a detailed specification is necessary because g(α) has been found to depend on all three parameters. The effect of varying v1 is well-known: the fraction of flat-spectrum sources increases with selection frequency. Variations of g(α) with S have also been found: both the fraction of flat-spectrum sources and the mean spectral index of the steep-spectrum sources depend on S, at least at high frequencies. The magnitude of this dependence on S as well as g(α) itself appear to depend on the choice of v2, or rather on the relation between v2 and v1. This complex behaviour of g(α) is not unexpected if one considers that the redshift and luminosity distributions of a source sample vary with selection frequency and flux density limit. Intrinsic or induced correlations between spectral index and redshift or luminosity, or different redshift distributions of flat-and steep-spectrum sources may cause variations of g(α) with v and S. An understanding of the behaviour of g(α) requires observations over large ranges of frequency and flux density. Even then, it will be difficult to interpret these data without information about the composition of the various samples, which can be obtained only through optical work. Here we describe recent spectral index information for weak sources selected at 1.4 GHz, as well as work on spectral index/optical identification correlations in 5 GHz samples.
We have recently mapped about a dozen Seyfert galaxies with the Very Large Array at 5 GHz and obtained less complete structural information on about a dozen more. Most sources are heavily resolved at resolutions near or below 1 arc sec, with linear scales in the range several hundred parsecs to a few kiloparsecs. For 3 galaxies (Mark 3, NGC 1068 and NGC 5548) the structure is double with two components more or less symmetrically placed on opposite sides of the optical nucleus. A third component, when present, coincides with the optical nucleus. This result provides strong evidence that “double radio source machines” also reside in the nuclei of active spiral galaxies as well as ellipticals. Other sources show a more diffuse morphology, but usually also possess a compact radio source associated with the optical continuum nucleus. A close relation between the extended radio emission and the thermal gas in the forbidden line region is indicated since (a) they have similar extents, (b) the radio and forbidden line powers are correlated, (c) the relativistic plus magnetic (B2eq/4π) and thermal pressures (nekTe) are similar and (d) the kinetic energy of the thermal gas and the minimum energy for synchrotron radiation are comparable. For the double sources, the radio emitting plasma is probably ejected from the compact nucleus and slowed by the large quantities of thermal gas in the forbidden line region. Alternatively, radio sources with more diffuse morphology may derive their luminosity from cosmic rays accelerated “in situ” by shock waves associated with the high velocity thermal gas and a magnetic field from a compressed (accreted?) interstellar medium.