1,063 research outputs found
ZFOURGE: Extreme 5007 emission may be a common early-lifetime phase for star-forming galaxies at
Using the \prospector\ spectral energy distribution (SED) fitting code, we
analyze the properties of 19 Extreme Emission Line Galaxies (EELGs) identified
in the bluest composite SED in the \zfourge\ survey at .
\prospector\ includes a physical model for nebular emission and returns
probability distributions for stellar mass, stellar metallicity, dust
attenuation, and nonparametric star formation history (SFH). The EELGs show
evidence for a starburst in the most recent 50 Myr, with the median EELG having
a specific star formation rate (sSFR) of 4.6 Gyr and forming 15\% of its
mass in this short time. For a sample of more typical star-forming galaxies
(SFGs) at the same redshifts, the median SFG has a sSFR of 1.1 Gyr and
forms only of its mass in the last 50 Myr. We find that virtually all of
our EELGs have rising SFHs, while most of our SFGs do not. From our analysis,
we hypothesize that many, if not most, star-forming galaxies at
undergo an extreme H+[\hbox{{\rm O}\kern 0.1em{\sc iii}}] emission
line phase early in their lifetimes. In a companion paper, we obtain
spectroscopic confirmation of the EELGs as part of our {\sc MOSEL} survey. In
the future, explorations of uncertainties in modeling the UV slope for galaxies
at are needed to better constrain their properties, e.g. stellar
metallicities.Comment: 11 pages, 5 figures (main figure is fig 5), accepted for publication
in Ap
Genetic study of congenital bile-duct dilatation identifies de novo and inherited variants in functionally related genes
published_or_final_versio
Status of water use and potential of rainwater harvesting for replacing centralized supply system in remote mountainous areas: a case study.
The failure of the centralized water supply system forced XY community to become more dependent on uncertain and unstable water sources. The results of surveying 50 households showed that 89.18% of total households depended on water collected from rivers, which contributed 58.3% of the total water volume used for the domestic demands. The average water volume consumed was 19.5 liters/person/day (l/p/d), and 86.5% of households used more than one source; 13.5% of households collected water only from rivers, and 45.94% of families had rainwater harvesting (RWH) for their activities (domestic water demand); however, RWH only provided 9.9% of total water consumption. In this study, basic methods were applied to calculate the storage tanks necessary to balance the water deficit created by drought months. Three levels of water demand (14, 20, and 30 l/p/d) can be the best choices for RWH; for a higher demand (40 and 60 l/p/d), small roof area (30-40 m2), and many people (six to seven) per family, RWH might be impractical because of unsuitable rainfall or excessively large storage tanks
Age-related changes in global motion coherence: conflicting haemodynamic and perceptual responses
Our aim was to use both behavioural and neuroimaging data to identify indicators of perceptual decline in motion processing. We employed a global motion coherence task and functional Near Infrared Spectroscopy (fNIRS). Healthy adults (n = 72, 18-85) were recruited into the following groups: young (n = 28, mean age = 28), middle-aged (n = 22, mean age = 50), and older adults (n = 23, mean age = 70). Participants were assessed on their motion coherence thresholds at 3 different speeds using a psychophysical design. As expected, we report age group differences in motion processing as demonstrated by higher motion coherence thresholds in older adults. Crucially, we add correlational data showing that global motion perception declines linearly as a function of age. The associated fNIRS recordings provide a clear physiological correlate of global motion perception. The crux of this study lies in the robust linear correlation between age and haemodynamic response for both measures of oxygenation. We hypothesise that there is an increase in neural recruitment, necessitating an increase in metabolic need and blood flow, which presents as a higher oxygenated haemoglobin response. We report age-related changes in motion perception with poorer behavioural performance (high motion coherence thresholds) associated with an increased haemodynamic response
Solitary waves in the Nonlinear Dirac Equation
In the present work, we consider the existence, stability, and dynamics of
solitary waves in the nonlinear Dirac equation. We start by introducing the
Soler model of self-interacting spinors, and discuss its localized waveforms in
one, two, and three spatial dimensions and the equations they satisfy. We
present the associated explicit solutions in one dimension and numerically
obtain their analogues in higher dimensions. The stability is subsequently
discussed from a theoretical perspective and then complemented with numerical
computations. Finally, the dynamics of the solutions is explored and compared
to its non-relativistic analogue, which is the nonlinear Schr{\"o}dinger
equation. A few special topics are also explored, including the discrete
variant of the nonlinear Dirac equation and its solitary wave properties, as
well as the PT-symmetric variant of the model
Performance of the CMS Cathode Strip Chambers with Cosmic Rays
The Cathode Strip Chambers (CSCs) constitute the primary muon tracking device
in the CMS endcaps. Their performance has been evaluated using data taken
during a cosmic ray run in fall 2008. Measured noise levels are low, with the
number of noisy channels well below 1%. Coordinate resolution was measured for
all types of chambers, and fall in the range 47 microns to 243 microns. The
efficiencies for local charged track triggers, for hit and for segments
reconstruction were measured, and are above 99%. The timing resolution per
layer is approximately 5 ns
Comparative study about the performance of three types of modified natural treatment systems for rice noodle wastewater
© 2019 Elsevier Ltd In this study, three semi-pilot scale systems (vertical flow constructed wetland, multi-soil layering, and integrated hybrid systems) for treating real rice noodle wastewater were operated parallelly for the first time in a tropical climate at a loading rate of 50 L/(m2·d) for more than 7 months to determine the optimal conditions and to compare their treatment performance. The results demonstrated that these systems were appropriate for the removal of organics, suspended solids, and total coliform (Tcol). The highest reductions in chemical oxygen demand (CODCr, 73.2%), phosphorus (PO4-P, 54%), and Tcol (4.78 log MPN/100 mL inactivation) were obtained by the integrated hybrid system, while the highest removal efficiencies of ammonium (NH4-N, 60.64%) and suspended solids (80.49%) were achieved in the vertical-flow-constructed wetland and multi-soil layering systems respectively
Dry semi-continuous anaerobic digestion of food waste in the mesophilic and thermophilic modes: New aspects of sustainable management and energy recovery in South Korea
© 2016 Elsevier Ltd In this study, parallel, bench-scale, mesophilic and thermophilic, dry, semi-continuous anaerobic digestion (DScAD) of Korea food waste (FW, containing 22% total solids (TS) and 20% volatile solids (VS)) was investigated thoroughly under varying operational conditions, including hydraulic retention times (HRTs) and organic loading rates (OLRs). The aim was to evaluate the start-up, stability, overall removal efficiency, and inhibitory effects of toxic compounds on process performance over a long-term operation lasting 100 days. The results from both digesters indicate that the simultaneous reduction of VS and the production of gas improved as the HRT decreased or the OLR increased. The highest average rates of VS reduction (79.67%) and biogas production (162.14 m3biogas/ton of FW, 61.89% CH4), at an OLR of 8.62 ± 0.34 kg VS/m3day (25 days of HRT), were achieved under thermophilic DScAD. In addition, the average rates of reduction of VS and the production of biogas in thermophilic DScAD were higher by 6.88% and 16.4%, respectively, than were those in mesophilic DScAD. The inhibitory effects of ammonia, H2S, and volatile fatty acids (VFAs) on methane production was not clear from either of the digesters, although, apparently, their concentrations did fluctuate. This fluctuation could be attributed to the self-adaptation of the microbial well. However, digestion that was more stable and faster was observed under thermophilic conditions compared with that under mesophilic conditions. Based on our results, the optimum operational parameters to improve FW treatment and achieve higher energy yields could be determined, expanding the application of DScAD in treating organic wastes
Performance of CMS muon reconstruction in pp collision events at sqrt(s) = 7 TeV
The performance of muon reconstruction, identification, and triggering in CMS
has been studied using 40 inverse picobarns of data collected in pp collisions
at sqrt(s) = 7 TeV at the LHC in 2010. A few benchmark sets of selection
criteria covering a wide range of physics analysis needs have been examined.
For all considered selections, the efficiency to reconstruct and identify a
muon with a transverse momentum pT larger than a few GeV is above 95% over the
whole region of pseudorapidity covered by the CMS muon system, abs(eta) < 2.4,
while the probability to misidentify a hadron as a muon is well below 1%. The
efficiency to trigger on single muons with pT above a few GeV is higher than
90% over the full eta range, and typically substantially better. The overall
momentum scale is measured to a precision of 0.2% with muons from Z decays. The
transverse momentum resolution varies from 1% to 6% depending on pseudorapidity
for muons with pT below 100 GeV and, using cosmic rays, it is shown to be
better than 10% in the central region up to pT = 1 TeV. Observed distributions
of all quantities are well reproduced by the Monte Carlo simulation.Comment: Replaced with published version. Added journal reference and DO
Genotyping and antibiotic resistance of thermophilic Campylobacter isolated from chicken and pig meat in Vietnam
Background Campylobacter species are recognized as the most common cause of
foodborne bacterial gastroenteritis in humans. In this study nine
Campylobacter strains isolated from chicken meat and pork in Hanoi, Vietnam,
were characterized using molecular methods and tested for antibiotic
resistance. Results The nine isolates (eight C. jejuni and one C. coli) were
identified by multiplex PCR, and tested for the presence or absence of 29 gene
loci associated with virulence, lipooligosaccharide (LOS) biosynthesis and
further functions. flaA typing, multilocus sequence typing and microarray
assay investigation showed a high degree of genetic diversity among these
isolates. In all isolates motility genes (flaA, flaB, flhA, fliM),
colonization associated genes (cadF, docB), toxin production genes (cdtA,
cdtB, secD, secF), and the LOS biosynthesis gene pglB were detected. Eight
gene loci (fliY, virB11, Cje1278, Cj1434c, Cj1138, Cj1438c, Cj1440c, Cj1136)
could not be detected by PCR. A differing presence of the gene loci ciaB (22.2
%), Cje1280 (77.8 %), docC (66.7 %), and cgtB (55.6 %) was found. iamA, cdtC,
and the type 6 secretion system were present in all C. jejuni isolates but not
in C. coli. flaA typing resulted in five different genotypes within C. jejuni,
MLST classified the isolates into seven sequence types (ST-5155, ST-6736,
ST-2837, ST-4395, ST-5799, ST-4099 and ST-860). The microarray assay analysis
showed a high genetic diversity within Vietnamese Campylobacter isolates which
resulted in eight different types for C. jejuni. Antibiotic susceptibility
profiles showed that all isolates were sensitive to gentamicin and most
isolates (88.8 %) were sensitive to chloramphenicol, erythromycin and
streptomycin. Resistance rates to nalidixic acid, tetracycline and
ciprofloxacin were 88.9, 77.8 and 66.7 %, respectively. Conclusions To the
best of our knowledge, this study is the first report that shows high genetic
diversity and remarkable antibiotic resistance of Campylobacter strains
isolated from meat in Vietnam which can be considered of high public health
significance. These preliminary data show that large scale screenings are
justified to assess the relevance of Campylobacter infections on human health
in Vietnam
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