2,533 research outputs found
Readout technologies for directional WIMP Dark Matter detection
The measurement of the direction of WIMP-induced nuclear recoils is a compelling but technologically challenging strategy to provide an unambiguous signature of the detection of Galactic dark matter. Most directional detectors aim to reconstruct the dark-matter-induced nuclear recoil tracks, either in gas or solid targets. The main challenge with directional detection is the need for high spatial resolution over large volumes, which puts strong requirements on the readout technologies. In this paper we review the various detector readout technologies used by directional detectors. In particular, we summarize the challenges, advantages and drawbacks of each approach, and discuss future prospects for these technologies
Discovery of 36 eclipsing EL CVn binaries found by the Palomar Transient Factory
We report the discovery and analysis of 36 new eclipsing EL CVn-type
binaries, consisting of a core helium-composition pre-white dwarf and an
early-type main-sequence companion, more than doubling the known population of
these systems. We have used supervised machine learning methods to search 0.8
million lightcurves from the Palomar Transient Factory, combined with SDSS,
Pan-STARRS and 2MASS colours. The new systems range in orbital periods from
0.46-3.8 d and in apparent brightness from ~14-16 mag in the PTF  or
 filters. For twelve of the systems, we obtained radial velocity
curves with the Intermediate Dispersion Spectrograph at the Isaac Newton
Telescope. We modelled the lightcurves, radial velocity curves and spectral
energy distributions to determine the system parameters. The radii (0.3-0.7
) and effective temperatures (8000-17000 K) of the
pre-He-WDs are consistent with stellar evolution models, but the masses
(0.12-0.28 ) show more variance than models predicted. This
study shows that using machine learning techniques on large synoptic survey
data is a powerful way to discover substantial samples of binary systems in
short-lived evolutionary stages
Family life cycle disruption in rural communities: The case of the Lake Shelbyville reservoir
This project assessed on an ex post facto basis selected impacts upon families and individuals due to the land acquisition program associated with the construction of the Shelbyville Reservoir in east-central Illinois begun in 1962. Research focused on Okaw Township, which borders Lake Shelbyville to the west in Shelby County. The in-depth, individual and family case studies indicated that farm family businesses are not the products of a single generation, or a single family. They are intimately tied to the intergenerational land transfer process which occurs among interconnected families living in close proximity. Thus, the time perspective in examining changes brought about by land acquisition and relocation must be extended on the generational level if the full range of impacts on the local cultural ecology is to be represented. Areawide changes in the availability and price of land made the difficult task of reestablishing a family farm even harder for selected families. The Corps' land acquisition policies in 1962 did not consider the generations involved in the establishment of family farms. Furthermore, local residents were critical of the Corps' policies and personnel during the land acquisition process. That historical complaint summarized by the quote, "the Corps is not a good neighbor," has even today hindered the Corps' ability to manage its relations with area residents and local government units. An understanding of the personal and family lifecycle perspectives on local cultural ecology, coupled with an appreciation of the degree to which rural social processes are bound in time, can strengthen State of Illinois comprehensive planning, decision-making, and review procedures for water and related resource development.U.S. Department of the InteriorU.S. Geological SurveyOpe
Rapid "Turn-on" of type 1 AGN in a quiescent early type galaxy SDSS1115+0544
We present a detailed study of a transient in the center of SDSS1115+0544
based on the extensive UV, optical, mid-IR light curves (LC) and spectra over
1200 days. The host galaxy is a quiescent early type galaxy at  = 0.0899
with a blackhole mass of . The transient underwent a 2.5
magnitude brightening over  days, reaching a peak -band luminosity
(extinction corrected) of  magnitude, then fading 0.5 magnitude over 200
days, settling into a plateau of  days. Following the optical brightening
are the significant mid-IR flares at  and m, with a peak time
delay of  days. The mid-IR LCs are explained as the echo of UV photons
by a dust medium with a radius of  cm, consistent with  of 0.58 inferred from the spectra. This event is very energetic with an
extinction corrected  erg s. Optical
spectra over 400 days in the plateau phase revealed newly formed broad
H emission with a FWHM of  km s and narrow
coronal lines such as [Fe VII], [Ne V]. This flare also has a steeply rising UV
continuum, detected by multi-epoch  data at  to  days post
optical peak. The broad Balmer lines and the UV continuum do not show
significant temporal variations. The slow evolving LCs over 1200 days, the
constant Balmer lines and UV continuum at late-times rule out TDE and SN IIn as
the physical model for this event. We propose that this event is a `turn-on'
AGN, transitioning from a quiescent state to a type 1 AGN with a sub-Eddington
accretion rate of /yr. This change occurred on a very short time
scale of  days. The discovery of such a rapid `turn-on' AGN
poses challenges to accretion disk theories and may indicate such event is not
extremely rare.Comment: Comments are welcome. Emails to the first author. Accepted for
  publication in Ap
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Quality of Surface Waters of the United States 1955
This report contains daily minimum and maximum temperature data for Waller Creek at 23rd Street between the months of March and September 1955.The quality-of-water Investigations of the United States Geological Survey are concerned with chemical and physical characteristics of the surface and groundwater supplies of the Nation. Most of the investigations carried on in cooperation with States and other Federal agencies deal with the amounts of matter in solution and in suspension in streams.
The records of chemical analysis, suspended sediment, and temperature for surface waters given in this volume serve as a basis for determining the suitability of the waters examined for industrial, agricultural, and domestic uses insofar as such use is affected by the dissolved or suspended mineral matter in the waters. The discharge of a stream and, to a lesser extent, the chemical quality are related to variations in rainfall and other forms of precipitation. In general, lower concentrations of dissolved solids may be expected during the periods of high flow than during periods of low flow. The concentration in some streams may change materially with relatively small variations in flow, whereas for other streams the quality may remain relatively uniform throughout large ranges in discharge. The quantities of suspended sediment carried by streams are also related to discharge, and during flood periods the sediment concentrations in many streams vary over wide ranges.
The regular yearly publication of records of chemical analyses, suspended sediment, and water temperature was begun by the Geological Survey in 1941. The annual records prior to 1948 were published in a single volume for the entire country. Beginning in 1948, the records were published in two volumes, and beginning in 1950, in four volumes, covering the drainage basins shown in figure 1. The samples for which data are given were collected from October 1, 1954, to September 30, 1955. Descriptive statements are given for each sampling station for which regular series of chemical analyses, temperature observations, or sediment determinations have been made. These statements include the location of the stream-sampling station, drainage area, length of time for which records are available, extremes of dissolved solids, hardness, sediment loads, water temperature, and other pertinent data. Records of water discharge of the streams at, or near, the sampling point for the sampling period are included in most tables of analyses. The records are arranged by drainage basins, according to Geological Survey practice in reporting records of streamflow.
During the year ended September 30, 1955, 160 regular sampling stations on 100 streams for the study of the chemical character of surface waters were maintained by the Geological Survey in the area covered by this volume. Samples were collected less frequently during the year at many other points. Water temperatures were measured daily at 123 of the regular sampling stations. Not all analyses of samples of surface water collected during the year have been included. Single analyses of an incomplete nature
generally have been omitted. Also, determinations made on the daily samples before compositing have not been reported. Specific conductance was usually determined on each daily sample, and as noted in the table headings this information is available for reference at the district offices listed under Division of Work, on page 22.
Quantities of suspended sediment are reported for 26 stations during the year ending September 30, 1955. The sediment samples were collected one or more times daily at most stations, depending on the rate of flow and changes in stage of the stream. Sediment samples were collected less frequently during the year at many other points. In connection with measurements of sediment discharge, sizes of sediment particles were determined at 25 of the stations.
Material which is transported almost in continuous contact with the stream bed and the material that bounces along the bed in short skips or leaps is termed " bedload" and is not considered in this report. All other undissolved fragmental material in transport is termed "suspended sediment" and generally constitutes the major part of the total sediment load. At the present time no reliable routine method has been developed for determining bedload.Waller Creek Working Grou
Folic acid induces cell type-specific changes in the transcriptome of breast cancer cell lines: a proof-of-concept study
The effect of folic acid (FA) on breast cancer (BC) risk is uncertain. We hypothesised that this uncertainty may be due, in part, to differential effects of FA between BC cells with different phenotypes. To test this we investigated the effect of treatment with FA concentrations within the range of unmetabolised FA reported in humans on the expression of the transcriptome of non-transformed (MCF10A) and cancerous (MCF7 and Hs578T) BC cells. The total number of transcripts altered was MCF10A 75 (70 up-regulated), MCF7 24 (14 up-regulated) and Hs578T 328 (156 up-regulated). Only the cancer-associated gene TAGLN was altered by FA in all three cell lines. In MCF10A and Hs578T cells, FA treatment decreased pathways associated with apoptosis, cell death and senescence, but increased those associated with cell proliferation. The folate transporters SLC19A1, SLC46A1 and FOLR1 were differentially expressed between cell lines tested. However, the level of expression was not altered by FA treatment. These findings suggest that physiological concentrations of FA can induce cell type-specific changes in gene regulation in a manner that is consistent with proliferative phenotype. This has implications for understanding the role of FA in BC risk. In addition, these findings support the suggestion the differences in gene expression induced by FA may involve differential activities of folate transporters. Together these findings indicate the need for further studies of the effect of FA on BC
Association between high dietary intake of the n-3 polyunsaturated fatty acid docosahexaenoic acid and reduced risk of Crohn's disease
Background: There are plausible mechanisms for how dietary docosahexaenoic acid (DHA), an n−3 polyunsaturated fatty acid, could prevent Crohn's disease (CD). Aim: To conduct a prospective study to investigate the association between increased intake of DHA and risk of CD. Methods: Overall, 229 702 participants were recruited from nine European centres between 1991 and 1998. At recruitment, dietary intakes of DHA and fatty acids were measured using validated food frequency questionnaires. The cohort was monitored through to June 2004 to identify participants who developed incident CD. In a nested case–control analysis, each case was matched with four controls; odds ratios (ORs) were calculated for quintiles of DHA intake, adjusted for total energy intake, smoking, other dietary fatty acids, dietary vitamin D and body mass index. Results: Seventy-three participants developed incident CD. All higher quintiles of DHA intake were inversely associated with development of CD; the highest quintile had the greatest effect size (OR = 0.07; 95% CI = 0.02–0.81). The OR trend across quintiles of DHA was 0.54 (95% CI = 0.30–0.99, Ptrend = 0.04). Including BMI in the multivariate analysis, due to its correlation with dietary fat showed similar associations. There were no associations with the other dietary fatty acids studied. Conclusion: There were inverse associations, with a biological gradient between increasing dietary docosahexaenoic acid intakes and incident Crohn's disease. Further studies in other populations should measure docosahexaenoic acid to determine if the association is consistent and the hypothesis tested in randomised controlled trials of purely docosahexaenoic acid supplementation
Fat and carbohydrate intake over three generations modify growth, metabolism and cardiovascular phenotype in female mice in an age-related manner
Environmental challenges such as a high fat diet during pregnancy can induce changes in offspring growth, metabolism and cardiovascular function. However, challenges that are sustained over several generations can induce progressive compensatory metabolic adjustments in young adults. It is not known if such effects persist during ageing. We investigated whether diets with different fat and carbohydrate contents over three generations modifies markers of ageing. Female C57BL/6 F0 mice were fed diets containing 5% or 21% fat (w/w) throughout pregnancy and lactation. Female offspring were fed the same diet as their dams until the F3 generation. In each generation, body weight, 24-hour food intake were recorded weekly, and plasma metabolites were measured by colorimetric assays, blood pressure by tail cuff plethysmography and vasoconstriction by myography on postnatal day 90 or 456. There was little effect of diet or generation on phenotypic markers in day 90 adults. There was a significant increase in whole body, liver and heart weight with ageing (d456) in the F3 21% fat group compared to the F1 and F3 5% groups. Fasting plasma glucose concentration was significantly increased with ageing in the 5% group in the F3 generation and in the 21% group in both generations. There was a significant effect of diet and generation on ex-vivo vasoconstriction in ageing females. Differences in dietary fat may induce metabolic compensation in young adults that persist over three generations. However, such compensatory effects decline during ageing
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