421 research outputs found
Analyses of pyrimidine and purine bases by a combination of paper chromatography and time of flight mass spectrometry
Paper chromatography and mass spectrometry for analyses of pyrimidine and purine base
Origin of Organic Matter in Early Solar System. I - Hydrocarbons
Formation of hydrocarbons by Fischer-Tropsch reaction involving carbon monoxide, hydrogen, and meteorite
ALMA twenty-six arcmin2 survey of GOODS-S at one millimeter (ASAGAO): Millimeter properties of stellar mass selected galaxies
We make use of the ASAGAO, deep 1.2 mm continuum observations of a 26
arcmin region in the GOODS-South field obtained with ALMA, to probe
dust-enshrouded star formation in -band selected (i.e., stellar mass
selected) galaxies, which are drawn from the ZFOURGE catalog. Based on the
ASAGAO combined map, which was created by combining ASAGAO and ALMA archival
data in the GOODS-South field, we find that 24 ZFOURGE sources have 1.2 mm
counterparts with a signal-to-noise ratio 4.5 (1 30 - 70
Jy beam at 1.2 mm). Their median redshift is estimated to be
2.38 0.14. They generally follow the tight
relationship of the stellar mass versus star formation rate (i.e., the main
sequence of star-forming galaxies). ALMA-detected ZFOURGE sources exhibit
systematically larger infrared (IR) excess (IRX ) compared to ZFOURGE galaxies without ALMA
detections even though they have similar redshifts, stellar masses, and star
formation rates. This implies the consensus stellar-mass versus IRX relation,
which is known to be tight among rest-frame-UV-selected galaxies, can not fully
predict the ALMA detectability of stellar-mass-selected galaxies. We find that
ALMA-detected ZFOURGE sources are the main contributors to the cosmic IR star
formation rate density at = 2 - 3.Comment: Accepted for publication in PASJ. A version with a high resolution
figure and ALMA fits files are available from
https://sites.google.com/view/asagao26
Inhibition of Fried Meat-Induced Colorectal DNA Damage and Altered Systemic Genotoxicity in Humans by Crucifera, Chlorophyllin, and Yogurt
Dietary exposures implicated as reducing or causing risk for colorectal cancer may reduce or cause DNA damage in colon tissue; however, no one has assessed this hypothesis directly in humans. Thus, we enrolled 16 healthy volunteers in a 4-week controlled feeding study where 8 subjects were randomly assigned to dietary regimens containing meat cooked at either low (100°C) or high temperature (250°C), each for 2 weeks in a crossover design. The other 8 subjects were randomly assigned to dietary regimens containing the high-temperature meat diet alone or in combination with 3 putative mutagen inhibitors: cruciferous vegetables, yogurt, and chlorophyllin tablets, also in a crossover design. Subjects were nonsmokers, at least 18 years old, and not currently taking prescription drugs or antibiotics. We used the Salmonella assay to analyze the meat, urine, and feces for mutagenicity, and the comet assay to analyze rectal biopsies and peripheral blood lymphocytes for DNA damage. Low-temperature meat had undetectable levels of heterocyclic amines (HCAs) and was not mutagenic, whereas high-temperature meat had high HCA levels and was highly mutagenic. The high-temperature meat diet increased the mutagenicity of hydrolyzed urine and feces compared to the low-temperature meat diet. The mutagenicity of hydrolyzed urine was increased nearly twofold by the inhibitor diet, indicating that the inhibitors enhanced conjugation. Inhibitors decreased significantly the mutagenicity of un-hydrolyzed and hydrolyzed feces. The diets did not alter the levels of DNA damage in non-target white blood cells, but the inhibitor diet decreased nearly twofold the DNA damage in target colorectal cells. To our knowledge, this is the first demonstration that dietary factors can reduce DNA damage in the target tissue of fried-meat associated carcinogenesis.ClinicalTrials.gov NCT00340743
ALMA deep field in SSA22: Blindly detected CO emitters and [C ii] emitter candidates
We report the identification of four millimeter line-emitting galaxies with the Atacama Large Milli/submillimeter Array (ALMA) in SSA22 Field (ADF22). We analyze the ALMA 1.1-mm survey data, with an effective survey area of 5 arcmin2, frequency ranges of 253.1–256.8 and 269.1–272.8 GHz, angular resolution of 0 ′′. .′′ 7 and rms noise of 0.8 mJy beam−1 at 36 km s−1 velocity resolution. We detect four line-emitter candidates with significance levels above 6σ. We identify one of the four sources as a CO(9–8) emitter at z = 3.1 in a member of the proto-cluster known in this field. Another line emitter with an optical counterpart is likely a CO(4–3) emitter at z = 0.7. The other two sources without any millimeter continuum or optical/near-infrared counterpart are likely to be [C II] emitter candidates at z = 6.0 and 6.5. The equivalent widths of the [C II] candidates are consistent with those of confirmed high-redshift [C II] emitters and candidates, and are a factor of 10 times larger than that of the CO(9–8) emitter detected in this search. The [C II] luminosity of the candidates are 4–7 × 108 L⊙. The star formation rates (SFRs) of these sources are estimated to be 10–20 M⊙ yr−1 if we adopt an empirical [C II] luminosity–SFR relation. One of them has a relatively low S/N ratio, but shows features characteristic of emission lines. Assuming that at least one of the two candidates is a [C II] emitter, we derive a lower limit of [C II]-based star formation rate density (SFRD) at z ∼ 6. The resulting value of >10−2 M⊙ yr−1 Mpc−3 is consistent with the dust-uncorrected UV-based SFRD. Future millimeter/submillimeter surveys can be used to detect a number of high-redshift line emitters, with which to study the star formation history in the early universe
ALMA twenty-six arcmin survey of GOODS-S at one-millimeter (ASAGAO): Near-infrared-dark faint ALMA sources
We report detections of two 1.2 mm continuum sources ( ~
0.6 mJy) without any counterparts in the deep - and/or -band image (i.e.,
-band magnitude 26 mag). These near-infrared-dark faint millimeter
sources are uncovered by ASAGAO, a deep and wide-field ( 26 arcmin)
Atacama Large Millimeter/submillimeter Array (ALMA) 1.2 mm survey. One has a
red IRAC (3.6 and 4.5 m) counterpart, and the other has been independently
detected at 850 and 870 m using SCUBA2 and ALMA Band 7, respectively.
Their optical to radio spectral energy distributions indicate that they can lie
at 3-5 and can be in the early phase of massive galaxy formation.
Their contribution to the cosmic star formation rate density is estimated to be
~ 1 10 yr Mpc if they lie somewhere in
the redshift range of ~ 3-5. This value can be consistent with, or greater
than that of bright submillimeter galaxies ( 4.2 mJy) at
~ 3-5. We also uncover 3 more candidates near-infrared-dark faint ALMA
sources without any counterparts ( ~ 0.45-0.86 mJy). These
results show that an unbiased ALMA survey can reveal the dust-obscured star
formation activities, which were missed in previous deep optical/near-infrared
surveys.Comment: 10 pages, 6 figures, accepted for publication in Ap
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