Recent work challenges traditional understandings of the link between race and voter turnout, suggesting that there is limited evidence of increased minority voting due to co-ethnic representation ...and majority-minority districts. Here I examine 65.3 million registration records from 10 states to trace individual-level participation before and after the 2012 round of redistricting, testing whether a shift in congressional representation, candidacy, and/or district ethnic composition affected an individual’s decision to participate. Separating results for non-Hispanic white, black, Latino, and Asian American registrants, I find that individuals change their behavior in response to ethnoracial context, with African Americans more likely to vote when assigned to majority-black districts with black candidates or incumbents. White and Asian registrants also turn out in higher numbers when a co-ethnic candidate is on the ballot, but Latinos may be less likely to vote in the short term when assigned to majority-Latino districts.
To obtain better statistics on the occurrence of magnetism among white dwarfs, we searched the spectra of the hydrogen atmosphere white dwarf stars (DAs) in the Data Release 7 of the Sloan Digital ...Sky Survey (SDSS) for Zeeman splittings and estimated the magnetic fields. We found 521 DAs with detectable Zeeman splittings, with fields in the range from around 1 to 733 MG, which amounts to 4 per cent of all DAs observed. As the SDSS spectra have low signal-to-noise ratios, we carefully investigated by simulations with theoretical spectra how reliable our detection of magnetic field was.
Plants detect competitors in shaded environments by perceiving a reduction in photosynthetically active radiation (PAR) and the reduction between the red and far‐red light (R:FR) ratio and blue ...photons. These light signals are detected by phytochromes and cryptochromes, which trigger shade avoidance responses such as shoot and petiole elongation and lead to increased susceptibility to pathogen attack. We studied morphological, anatomical, and photosynthesis differences in potato plants (Solanum tuberosum var. Spunta) exposed to sunlight or simulated shade in a greenhouse. We found that simulated shade strongly induced stem and internode elongation with a higher production of free auxin in stems and a lower production of tubers. The mesophyll thickness of the upper leaves of plants grown in simulated shade was lower, but the epidermis was wider compared with the leaves of plants cultivated in sunlight. In addition, the photosynthesis rate was lower in the upper leaves exposed to nonsaturated irradiances and higher in the basal leaves at saturated irradiances compared with control plants. RNA‐seq analysis showed that 146 and 155 genes were up‐ and downregulated by shade, respectively. By quantitative reverse transcription polymerase chain reaction, we confirmed that FLOWERING LOCUS T (FT), WRKY‐like, and PAR1b were induced, while FLAVONOL 4‐SULFOTRANSFERASE was repressed under shade. In shaded plants, leaves and tubers were more susceptible to the necrotrophic fungus Botrytis cinerea attack. Overall, our work demonstrates configurational changes between growth and defense decisions in potato plants cultivated in simulated shade.
Microencapsulation of lipase from
IMUFRJ 50682 was performed by ionotropic gelation with sodium alginate. Sodium alginate, calcium chloride and chitosan concentrations as well as complexation time ...were evaluated through experimental designs to increase immobilization yield (IY) and immobilized lipase activity (ImLipA) using
-nitrophenyl laurate as substrate. To adjust both parameters (IY and ImLipA), the desirability function showed that microcapsule formation with 3.1%(
/
) sodium alginate, 0.19%(
/
) chitosan, 0.14 M calcium chloride, and 1 min complexation time are ideal for maximal immobilization yield and immobilized lipase activity. A nearly twofold enhancement in Immobilization yield and an increase up to 280 U/g of the lipase activity of the microcapsules were achieved using the experimental design optimization tool. Chitosan was vital for the high activity of this new biocatalyst, which could be reused a second time with about 50% of initial activity and for four more times with about 20% of activity.
ABSTRACT
The spectral classification ‘subdwarf A’ (sdA) is given to stars showing H-rich spectra and sub-main-sequence surface gravities, but effective temperature lower than the zero-age horizontal ...branch. Their evolutionary origin is an enigma. In this work, we discuss the results of follow-up observations of selected sdAs. We obtained time-resolved spectroscopy for 24 objects and time-series photometry for another 19 objects. For two targets, we report both spectroscopy and photometry observations. We confirm seven objects to be new extremely low-mass white dwarfs (ELMs), one of which is a known eclipsing star. We also find the eighth member of the pulsating ELM class.
Abstract
Trojan asteroids are small bodies orbiting around the
L
4
or
L
5
Lagrangian points of a Sun-planet system. Due to their peculiar orbits, they provide key constraints to the Solar System ...evolution models. Despite numerous dedicated observational efforts in the last decade, asteroid 2010 TK
7
has been the only known Earth Trojan thus far. Here we confirm that the recently discovered 2020 XL
5
is the second transient Earth Trojan known. To study its orbit, we used archival data from 2012 to 2019 and observed the object in 2021 from three ground-based observatories. Our study of its orbital stability shows that 2020 XL
5
will remain in
L
4
for at least 4 000 years. With a photometric analysis we estimate its absolute magnitude to be
$${H}_{r}=18.5{8}_{-0.15}^{+0.16}$$
H
r
=
18.5
8
−
0.15
+
0.16
, and color indices suggestive of a C-complex taxonomy. Assuming an albedo of 0.06 ± 0.03, we obtain a diameter of 1.18 ± 0.08 km, larger than the first known Earth Trojan asteroid.
ABSTRACT
We study in detail the inner ∼600 pc of the Seyfert 2 galaxy ESO 138-G001 by means of the Soar Integral Field Spectrograph attached to the SOAR telescope. This source is known for displaying ...a very rich coronal line spectrum and a blob of high-excitation emission ∼3 arcsec south-east (SE) of the active galactic nucleus (AGN). The nature of this emission has not been fully understood yet. The excellent spatial and spectral resolution of SIFS allows us to confirm that the bulk of the coronal line forest emission region is very compact, of ∼0.8 arcsec in diameter, centred on the AGN and most likely powered by radiation from the AGN. In addition, evidence of a nuclear outflow, restricted to the inner 1 arcsec centred at the nucleus is found based on the detection of broad components in the most important emission lines. The gas in the inner few tens of parsecs filters out the AGN continuum so that the NLR is basically illuminated by a modified SED. This scenario is confirmed by means of photoionization models that reproduce the most important lines detected in the SIFS field of view. From the modelling, we also found that the black hole mass MBH of the AGN is about 105.50 M⊙, in agreement with previous X-ray observations. The spectrum of the SE blob is dominated by emission lines of low- to mid-ionization, with no hints of coronal lines. Our results show that it represents gas in the ionization cone that is photoionized by the filtered central AGN continuum.
Sex steroid hormones play an important role in fetal development, brain functioning and neuronal protection. Growing evidence highlights the positive effects of these hormones against brain damage ...induced by neonatal hypoxia-ischemia (HI). This systematic review with meta-analysis aims to verify the efficacy of sex steroid hormones in preventing HI-induced brain damage in rodent models. The protocol was registered at PROSPERO and a total of 22 articles were included. Moderate to large effects were observed in HI animals treated with sex steroid hormones in reducing cerebral infarction size and cell death, increasing neuronal survival, and mitigating neuroinflammatory responses and astrocyte reactivity. A small effect was evidenced for cognitive function, but no significant effect for motor function; moreover, a high degree of heterogeneity was observed. In summary, data suggest that sex steroid hormones, such as progesterone and 17β estradiol, improve morphological and cellular outcomes following neonatal HI. Further research is paramount to examine neurological function during HI recovery and standardization of methodological aspects is imperative to reduce the risk of spurious findings.
•Morphological parameters can benefit from sex steroid hormonal intervention after neonatal HI.•Sex steroid hormones cause protective effects associated to neuronal ang glial function that counteract HI-induced damage.•Small overall effect was found for cognitive and motor function.•Sex differences related to steroid hormone treatment following neonatal HI remain poorly understood.
Leading theories of race and participation posit that minority voters are mobilized by co-ethnic candidates. However, past studies are unable to disentangle candidate effects from factors associated ...with the places from which candidates emerge. I reevaluate the links between candidate race, district composition, and turnout by leveraging a nationwide database of over 185 million individual registration records, including estimates for the race of every voter. Combining these records with detailed information about 3,000 recent congressional primary and general election candidates, I find that minority turnout is not higher in districts with minority candidates, after accounting for the relative size of the ethnic group within a district. Instead, Black and Latino citizens are more likely to vote in both primary and general elections as their share of the population increases, regardless of candidate race.
Context.
NGC 1232 is a face-on spiral galaxy that serves as an excellent laboratory for the study of star formation due to its proximity. Recent studies have revealed interesting features about this ...galaxy: X-ray observations suggest that it recently collided with a dwarf galaxy, however, no apparent remnant is observed.
Aims.
In this study, we search for evidence of this possible collision.
Methods.
We used long-slit optical spectra of the galaxy in two different positions obtained with the Goodman spectrograph at the SOAR telescope.
Results.
We detected 18 HII regions in the north-south direction and 22 HII regions in the east-west direction and a background galaxy, NGC 1232B, for which we present the first redshift measurement and spectral analysis. We used the stellar population fitting technique to study the underlying stellar population of NGC 1232 and NGC 1232B and to subtract it from the spectra to measure the emission lines. The emission lines were used to determine the extinction, electron density, chemical abundance, and the star-formation rate gradient of NGC 1232.
Conclusions.
As is common in spiral galaxies, we found a stellar population gradient with older populations at the central regions and younger ones towards the outskirts, along with a negative oxygen abundance gradient of −0.16 dex/r
e
. Due to the difficulty of measuring important emission lines, the number of objects for the abundance gradient is small, but there is a hint that this galaxy has a broken gradient profile, with a drop towards the center. Some authors have explained this effect as the result of a satellite collision, but observations of a large sample of spiral galaxies shows evidence that goes against such a mechanism. If the collision caused any disturbance in the galaxy, we believe it would be small and hard to detect with a limited number of objects. From all the other measurements, we found no deviations from a typical spiral galaxy and no significant difference between different directions in the galaxy. The stellar population and emission line analysis of NGC 1232B suggest that it is a starburst galaxy.
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