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We present the luminosity function and selection function of 60 μm galaxies selected from the Imperial IRAS-FSC Redshift Catalogue. Three methods, including the and the parametric and non-parametric maximum-likelihood estimators, are used and the results agree well with each other. A density evolution or a luminosity evolution where tL is the look-back time, is detected in the full sample in the redshift range [0.02, 0.1], consistent with previous analyses. Of the four infrared subpopulations, cirrus-type galaxies and M82-type starbursts show similar evolutionary trends, galaxies with significant active galactic nucleus contributions show stronger positive evolution and Arp 220-type starbursts exhibit strong negative evolution. The dominant subpopulation changes from cirrus-type galaxies to M82-type starbursts at . In the second half of the paper, we derive the projected two-point spatial correlation function for galaxies of different infrared template types. The mean relative bias between cirrus-type galaxies and M82-type starbursts, which correspond to quiescent galaxies with optically thin interstellar dust and actively star-forming galaxies, respectively, is calculated to be . The relation between the current star formation rate (SFR) in star-forming galaxies and environment is investigated by looking at the dependence of clustering on infrared luminosity. We found that M82-type actively star-forming galaxies show stronger clustering as infrared luminosity/SFR increases. The correlation between the clustering strength and SFR in the local Universe seems to echo the basic trend seen in star-forming galaxies in the Great Observatories Origins Deep Survey fields (at ). [ABSTRACT FROM AUTHOR]

A privacy violation occurs when the association between an individual identity and data considered private by that individual is obtained by an unauthorized party. Uncertainty and indistinguishability are two independent aspects that characterize the degree of this association being revealed. Indistinguishability refers to the property that the attacker cannot see the difference among a group of individuals, while uncertainty refers to the property that the attacker cannot tell which private value, among a group of values, an individual actually has. This paper investigates the notion of indistinguishability as a general form of anonymity, applicable, for example, not only to generalized private tables, but to relational views and to sets of views obtained by multiple queries over a private database table. It is shown how indistinguishability is highly influenced by certain symmetries among individuals, in the released data, with respect to their private values. The paper provides both theoretical results and practical algorithms for checking if a specific set of views over a private table provide sufficient indistinguishability. [ABSTRACT FROM AUTHOR]

We present a careful analysis of the point-source detection limit of the AKARI All-Sky Survey in the WIDE-S 90-μm band near the North Ecliptic Pole (NEP). Timeline analysis is used to detect IRAS ( Infrared Astronomy Satellite) sources and then a conversion factor is derived to transform the peak timeline signal to the interpolated 90-μm flux of a source. Combined with a robust noise measurement, the point-source flux detection limit at signal-to-noise ratio for a single detector row is which corresponds to a point-source detection limit of the survey of ∼0.4 Jy. Wavelet transform offers a multiscale representation of the Time Series Data (tsd). We calculate the continuous wavelet transform of thetsd and then search for significant wavelet coefficients considered as potential source detections. To discriminate real sources from spurious or moving objects, only sources with confirmation are selected. In our multiscale analysis, IRAS sources selected above 4σ can be identified as the only real sources at the Point Source Scales. We also investigate the correlation between the non- IRAS sources detected in timeline analysis and cirrus emission using wavelet transform and contour plots of wavelet power spectrum. It is shown that the non- IRAS sources are most likely to be caused by excessive noise over a large range of spatial scales rather than real extended structures such as cirrus clouds. [ABSTRACT FROM AUTHOR]

Community archiving is grounded in grassroots documentation projects. This article, collectively written by an instructor and students of a community archiving course in a professional ischool, describes a process of teaching community archiving in ways that draw on and embrace community archiving principles and ethos rather than operating in opposition to them. It argues that teaching community archiving can create a classroom community that becomes a community archive in itself, and this article acts as one artifact created in the overall process. The article also offers information on the course outline, outcomes, pedagogical approach, and projects - some of which are documented in the text - that may be useful to other archival educators. It emphasizes the value of the personal, affective, and collaborative aspects of archival practice that are emphasized in community archiving practice and literature, and it also draws attention to the ways in which these operate as dimensions of pedagogy and classroom community, allowing both the content and delivery of the class to work in harmony. [ABSTRACT FROM AUTHOR]

We present stacked average far-infrared spectra of a sample of 197 dusty star-forming galaxies (DSFGs) at using about 90% of the Herschel Space Observatory SPIRE Fourier Transform Spectrometer (FTS) extragalactic data archive based on 3.5 years of science operations. These spectra explore an observed-frame 447–1568 GHz frequency range, allowing us to observe the main atomic and molecular lines emitted by gas in the interstellar medium. The sample is subdivided into redshift bins, and a subset of the bins are stacked by infrared luminosity as well. These stacked spectra are used to determine the average gas density and radiation field strength in the photodissociation regions (PDRs) of DSFGs. For the low-redshift sample, we present the average spectral line energy distributions of CO and H2O rotational transitions and consider PDR conditions based on observed [C i] 370 and 609 μm, and CO (7-6) lines. For the high-z () sample, PDR models suggest a molecular gas distribution in the presence of a radiation field that is at least a factor of 103 larger than the Milky Way and with a neutral gas density of roughly – cm−3. The corresponding PDR models for the low-z sample suggest a UV radiation field and gas density comparable to those at high-z. Given the challenges in obtaining adequate far-infrared observations, the stacked average spectra we present here will remain the measurements with the highest signal-to-noise ratio for at least a decade and a half until the launch of the next far-infrared facility. [ABSTRACT FROM AUTHOR]

We study the radio emission of the most massive galaxies in a sample of dynamically relaxed and unrelaxed galaxy groups from the Galaxy and Mass Assembly survey. The dynamical state of the group is defined by the stellar dominance of the brightest group galaxy (BGG), e.g., the luminosity gap between the two most luminous members, and the offset between the position of the BGG and the luminosity centroid of the group. We find that the radio luminosity of the largest galaxy in the group strongly depends on its environment, such that the BGGs in dynamically young (evolving) groups are an order of magnitude more luminous in the radio than those with a similar stellar mass but residing in dynamically old (relaxed) groups. This observation has been successfully reproduced by a newly developed semi-analytic model that allows us to explore the various causes of these findings. We find that the fraction of radio-loud BGGs in the observed dynamically young groups is ∼2 times that of the dynamically old groups. We discuss the implications of this observational constraint on the central galaxy properties in the context of galaxy mergers and the super massive black hole accretion rate. [ABSTRACT FROM AUTHOR]

Submillimeter galaxies (SMGs) at are luminous in the far-infrared, and have star formation rates, SFR, of hundreds to thousands of solar masses per year. However, it is unclear whether they are true analogs of local ULIRGs or whether the mode of their star formation is more similar to that in local disk galaxies. We target these questions by using Herschel-PACS to examine the conditions in the interstellar medium (ISM) in far-infrared luminous SMGs at –4. We present 70–160 μm photometry and spectroscopy of the [O iv]26 μm, [Fe ii]26 μm, [S iii]33 μm, [Si ii]34 μm, [O iii]52 μm, [N iii]57 μm, and [O i]63 μm fine-structure lines and the S(0) and S(1) hydrogen rotational lines in 13 lensed SMGs identified by their brightness in early Herschel data. Most of the 13 targets are not individually spectroscopically detected; we instead focus on stacking these spectra with observations of an additional 32 SMGs from the Herschel archive—representing a complete compilation of PACS spectroscopy of SMGs. We detect [O i]63 μm, [Si ii]34 μm, and [N iii]57 μm at in the stacked spectra, determining that the average strengths of these lines relative to the far-IR continuum are , , and , respectively. Using the [O iii]52 μm/[N iii]57 μm emission line ratio, we show that SMGs have average gas-phase metallicities . By using PDR modeling and combining the new spectral measurements with integrated far-infrared fluxes and existing [C ii]158 μm data, we show that SMGs have average gas densities, n, of and FUV field strengths, (in Habing units: ), consistent with both local ULIRGs and lower luminosity star-forming galaxies. [ABSTRACT FROM AUTHOR]

Chilling temperatures induce an increase in cytoplasmic calcium (Ca2+) ions to transmit cold signals, but the precise role of Calmodulins (CaMs), a type of Ca2+ sensor, in plant tolerance to cold stress remains elusive. In this study, we characterized a tomato (Solanum lycopersicum) CaM gene, CALMODULIN6 (CaM6), which responds to cold stimulus. Overexpressing CaM6 increased tomato sensitivity to cold stress whereas silencing CaM6 resulted in a cold-insensitive phenotype. We showed that CaM6 interacts with Inducer of CBF expression 1 (ICE1) in a Ca2+-independent process and ICE1 contributes to cold tolerance in tomato plants. By integrating RNA-sequencing (RNA-seq) and chromatin immunoprecipitation-sequencing (ChIP-seq) assays, we revealed that ICE1 directly altered the expression of 76 downstream cold-responsive (COR) genes that potentially confer cold tolerance to tomato plants. Moreover, the physical interaction of CaM6 with ICE1 attenuated ICE1 transcriptional activity during cold stress. These findings reveal that CaM6 attenuates the cold tolerance of tomato plants by suppressing ICE1-dependent COR gene expression. We propose a CaM6/ICE1 module in which ICE1 is epistatic to CaM6 under cold stress. Our study sheds light on the mechanism of plant response to cold stress and reveals CaM6 is involved in the regulation of ICE1. [ABSTRACT FROM AUTHOR]

Spontaneous plasmid transformation of Escherichia coli occurs on nutrient-containing agar plates. E. coli has also been reported to use double-stranded DNA (dsDNA) as a carbon source. The mechanism(s) of entry of exogenous dsDNA that allows plasmid establishment or the use of DNA as a nutrient remain(s) unknown. To further characterize plasmid transformation, we first documented the stimulation of transformation by agar and agarose. We provide evidence that stimulation is not due to agar contributing a supplement of Ca2+, Fe2+, Mg2+, Mn2+, or Zn2+. Second, we undertook to inactivate the E. coli orthologues of Haemophilus influenzae components of the transformation machine that allows the uptake of single-stranded DNA (ssDNA) from exogenous dsDNA. The putative outer membrane channel protein (HofQ), transformation pseudopilus component (PpdD), and transmembrane pore (YcaI) are not required for plasmid transformation. We conclude that plasmid DNA does not enter E. coli cells as ssDNA. The finding that purified plasmid monomers transform E. coli with single-hit kinetics supports this conclusion; it establishes that a unique monomer molecule is sufficient to give rise to a transformant, which is not consistent with the reconstitution of an intact replicon through annealing of partially overlapping complementary ssDNA, taken up from two independent monomers. We therefore propose that plasmid transformation involves internalization of intact dsDNA molecules. Our data together, with previous reports that HofQ is required for the use of dsDNA as a carbon source, suggest the existence of two routes for DNA entry, at least across the outer membrane of E. coli. [ABSTRACT FROM AUTHOR]

In galaxy clusters, efficiently accreting active galactic nuclei (AGNs) are preferentially located in the infall regions of the cluster projected phase-space, and are rarely found in the cluster core. This has been attributed to both an increase in triggering opportunities for infalling galaxies, and a reduction of those mechanisms in the hot, virialized, cluster core. Exploiting the depth and completeness (98 per cent at r < 19.8mag) of the Galaxy And Mass Assembly survey (GAMA), we probe down the group halo mass function to assess whether AGNs are found in the same regions in groups as they are in clusters. We select 451 optical AGNs from 7498 galaxies with log10(M*/M☉) > 9.9 in 695 groups with 11.53⩽log10(M200/M☉)⩽14.56 at z < 0.15. By analysing the projected phase-space positions of these galaxies, we demonstrate that when split both radially and into physically derived infalling and core populations, AGN position within group projected phase-space is dependent on halo mass. For groups with log10(M200/M☉)>13.5,AGNs are preferentially found in the infalling galaxy population with 3.6σ confidence. At lower halo masses, we observe no difference in AGN fraction between core and infalling galaxies. These observations support a model where a reduced number of low-speed interactions, ram pressure stripping and intra-group/cluster medium temperature, the dominance of which increase with halo mass, work to inhibit AGN in the cores of groups and clusters with log10(M200/M☉) > 13.5, but do not significantly affect nuclear activity in cores of less massive structures. [ABSTRACT FROM AUTHOR]

We apply four statistical learning methods to a sample of 7941 galaxies (z < 0.06) from the Galaxy And Mass Assembly survey to test the feasibility of using automated algorithms to classify galaxies. Using 10 features measured for each galaxy (sizes, colours, shape parameters, and stellar mass), we apply the techniques of Support Vector Machines, Classification Trees, Classification Trees with Random Forest (CTRF) and Neural Networks, and returning True Prediction Ratios (TPRs) of 75.8 per cent, 69.0 per cent, 76.2 per cent, and 76.0 per cent, respectively. Those occasions whereby all four algorithms agree with each other yet disagree with the visual classification (‘unanimous disagreement’) serves as a potential indicator of human error in classification, occurring in ∼ 9 per cent of ellipticals, ∼ 9 per cent of little blue spheroids, ∼ 14 per cent of early-type spirals, ∼ 21 per cent of intermediate-type spirals, and ∼ 4 per cent of late-type spirals and irregulars. We observe that the choice of parameters rather than that of algorithms is more crucial in determining classification accuracy. Due to its simplicity in formulation and implementation, we recommend the CTRF algorithm for classifying future galaxy data sets. Adopting the CTRF algorithm, the TPRs of the five galaxy types are : E, 70.1 per cent; LBS, 75.6 per cent; S0–Sa, 63.6 per cent; Sab–Scd, 56.4 per cent, and Sd–Irr, 88.9 per cent. Further, we train a binary classifier using this CTRF algorithm that divides galaxies into spheroid-dominated (E, LBS, and S0–Sa) and disc-dominated (Sab–Scd and Sd–Irr), achieving an overall accuracy of 89.8 per cent. This translates into an accuracy of 84.9 per cent for spheroid-dominated systems and 92.5 per cent for disc-dominated systems. [ABSTRACT FROM AUTHOR]

• A 5000 h multi-factor accelerated aging test was carried out. • The aging performance of modified polyurethane composites for transmission line towers with different processes were investigated. • The influence of ultraviolet absorber and ultraviolet stabilizer on polyurethane composites was studied. • An aging performance improvement scheme of polyurethane composites was proposed. Fiber reinforced plastic has the characteristics of light weight, high strength, good aging performance and strong insulation performance, so the composite overhead transmission line tower may become a substitute for the traditional iron tower in the future. At present, the researches on the composite transmission tower mainly focused on the electrical properties, few on the aging performance, which is an unknown influence on the transmission line with composite transmission towers. In this paper, a 5000 h multi-factor accelerated aging test was used to investigate the aging performance of modified polyurethane (PU) composites for composite transmission towers. The test periodically simulated the environment of high voltage, rainfall, humidity, alternating high and low temperatures, ultraviolet and salt fog. The results show that pultrusion process PU composites are more suitable to be used as the materials of composite towers because of its higher bending modulus. Then, a research on PU composites aging performance improvement scheme was carried out by another multi-factor accelerated aging test. The results show that the mixture of ultraviolet absorber and ultraviolet stabilizer is helpful to improve the aging performance of PU composites, and the addition of 0.275wt% of the total amount with a ratio of 1:1 is a viable scheme. [ABSTRACT FROM AUTHOR]